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died Aug. 28, 1818, St. Charles, Mo., U.S.
black pioneer trader and founder of the settlement that later became the city of Chicago.
Du Sable, whose French father had moved to Haiti and married a black woman there, is believed to have been a freeborn. At some time in the 1770s he went to the Great Lakes area of North America, settling on the shore of Lake Michigan at the mouth of the Chicago River, with his Potawatomi wife, Kittihawa (Catherine). His loyalty to the French and the Americans led to his arrest in 1779 by the British, who took him to Fort Mackinac. From 1780 to 1783 or 1784 he managed for his captors a trading post called the Pinery on the St. Clair River in present-day Michigan, after which he returned to the site of Chicago. By 1790 Du Sable's establishment there had become an important link in the region's fur and grain trade.
In 1800 he sold out and moved to Missouri, where he continued as a farmer and trader until his death. But his 20-year residence on the shores of Lake Michigan had established his title as Father of Chicago.
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Tornadoes are the most intense storms on the planet, and they’re never discussed without at least some mention of the term wind shear. Many of us sitting at home, though, have no idea what wind shear is, or if we do, how it affects tornado production.
What is Wind Shear
Wind shear, although it might sound complex, is a simple concept. Wind shear is merely the change in wind with height, in terms of wind direction and speed. I think that we all understand that the wind is generally stronger in the atmosphere over our heads than it is here on the ground, and if we think of the atmosphere in terms of the three dimensions that it has, it should not be surprising that the wind above us might also be blowing from a different direction than the wind at the ground. When that happens–the wind speed and direction vary with height–wind shear is occurring.
Wind Shear and Supercell Thunderstorms
This wind shear is an important part of the process in the development of a supercell thunderstorm, from which the vast majority of strong tornadoes form.
All thunderstorms are produced by a powerful updraft–a surge of air that rises from the ground into the upper levels of the atmosphere, and when this updraft forms in an area where wind shear is present, the updraft is influence by this speed and different direction of the wind above, pushing the column of air in the updraft into a more vertical alignment.
Rain’s Influence on Tornado Production
Needless to say, thunderstorms typically produce very heavy rain, and rain-cooled air is much heavier than the warm air of the updraft, so the rain-cooled air, produces a compensating downdraft (what comes up, must come down). This downdraft pushes the part of the rotating air that was forced in its direction by the stronger wind aloft downward, and the result is a horizontal column of rotating air.
That’s Not a Tornado!
I know what you’re thinking that you’ve seen enough TLC or Discovery Channel shows to know that a horizontal column of air is NOT a tornado; you need a vertical column of air.
This Can Be a Tornado
You’re right, but remember the updraft that is driving the thunderstorm is still working, and it’s able to pull the horizontal, spinning column of air into the thunderstorm, resulting in a vertical column of spinning air.
(NOAA image showing vertical column of air in a supercell thunderstorm)
The result is a rotating thunderstorm capable of producing a tornado, and it would not be possible without wind shear.
(NOAA image showing tornado formation in supercell thunderstorm)
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On this day in 1951, more than six years after the end of World War II in Europe, President Harry S. Truman signed a proclamation officially ending U.S. hostilities with Germany.
The official end to the war came nine years, 10 months and 13 days after Congress had declared war on Nazi Germany. The lawmakers had responded to a declaration of war issued by the Third Reich in the aftermath of the Dec. 7, 1941, Japanese attack on Pearl Harbor and other U.S. bases in the Pacific.
The president explained why he had waited so long after the fighting had ended to act: It had always been America’s hope, Truman wrote, to create a treaty of peace with the government of a united and free Germany, but the postwar policies pursued by the Soviet Union “made it impossible.”
After the war, the United States, Britain, France and the Soviet Union divided Germany into four zones of occupation. Berlin, while located wholly within the Soviet zone, was jointly occupied by the wartime allies and also subdivided into four sectors because of its symbolic importance as the nation’s historic capital and seat of the former Nazi government.
The three western zones were merged to form the Federal Republic of Germany in May 1949, and the Soviets followed suit in October 1949 with the establishment of the German Democratic Republic.
The East German regime began to falter in May 1989, when the removal of Hungary’s border fences punched a hole in the Iron Curtain, allowing tens of thousands of East Germans to flee to the West. Despite the grants of general sovereignty to both German states in 1955, neither of the two German governments held unrestricted sovereignty under international law until after they were reunified in October 1990.
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The significance of Alabama Unionists during the Civil War and Reconstruction has long been a subject of study among scholars. Largely centered in northern Alabama and to a lesser degree in the southeast region and in Montgomery and Mobile, Unionists were important both militarily and politically. Until recently, however, the details of this phenomenon have remained less well known, largely because the term Unionist (both then and now) has been used to refer to a range of different individuals and positions.
In the broadest sense, Unionist has meant any white person who opposed secession (including those who later supported the Confederacy) and those who came to support the Union during the war despite having originally supported the Confederacy. This broad definition includes a very wide range of Alabamians—from the most well-to-do planters who ultimately become officers in the Confederate Army to the subsistence farmer who deserted the southern cause midway through the war. It is also possible to define Unionism more narrowly, confining the label to those individuals who resisted both secession and the Confederacy during the war. Such unconditional loyalists probably represented no more than 15 percent of Alabama's adult white population. They were mostly nonslaveholding farmers (though a small minority owned slaves) living in the northern third of the state. A few Unionists also lived in the piney woods and coastal plain further south. In many respects, these men and women were very much like their neighbors who supported the Confederate cause. The reasons they remained loyal to the Union were also quite diverse. Many saw secession as illegal, whereas others felt that it would dishonor the American Revolution and their own ancestors. Still others were certain that secession would end in political or military disaster. Many were influenced by the respected figures in their families or neighborhoods.
Unionism in Alabama arose under the pressures of the presidential election of 1860. Nine months before, the state legislature had directed that, in the event of a Republican's election, a state secession convention would be called. By directly linking the presidential election to secession, the legislature fostered a political atmosphere that was particularly hostile to Unionists. Newspaper editorials and participants at community meetings condemned as traitors those who canvassed for Illinois senator Stephen Douglas, the nominee of the regular Democratic Party, rather than the southern-rights Democratic nominee, John Breckinridge. In the election, fully 80 percent of Alabama's eligible voters participated, giving Breckinridge a substantial victory, with 54 percent of the vote. John Bell, the Constitutional Union candidate who was supported by a number of Alabamians hostile to secession, received 31 percent of the vote. Douglas, the candidate most associated with a strongly Unionist position, polled slightly more than 15 percent. Republican Abraham Lincoln was not even on the ballot in Alabama.
As promised, Alabama secessionists called a convention in the wake of Lincoln's election. The campaign for convention delegates provoked heated and sometimes violent debates among neighbors, forcing many to defend their positions in public. Of the 100 delegates elected, 53 were secessionists and 47 were cooperationists, a term that refers to the delegates' desire to secede only in "cooperation" with other southern states. In fact, the men elected on this platform represented a wide range of ideas about if, when, and under what circumstances to cooperate with secession and included a minority faction—probably less than one-third (the vast majority of them from the northern third of the state)—of unconditional Unionists who opposed secession outright.
These delegates convened in Montgomery on January 7, 1861, and debated secession for four days. On January 11, 1861, the convention passed Alabama's Ordinance of Secession by a vote of 61 to 39. Many of those who voted against the ordinance, however, ultimately did support secession, and four immediately reversed themselves and signed with the majority. Among the opposition, 33 delegates subsequently signed the "Address to the People of Alabama," in which they pledged to consult with their supporters and then act on their wishes. Ten signatories of the address signed the ordinance to satisfy their constituents. Other delegates who rejected the ordinance eventually took active part in the war. Only three signers—Henry C. Sanford of Cherokee County, Elliot P. Jones of Fayette County, and Robert Guttery of Walker County—never signed the ordinance and maintained their Unionism throughout the war. Only two wartime Unionists—R. S. Watkins of Franklin County and Christopher C. Sheats of Winston County—signed neither the "Address" nor the Ordinance of Secession.
Most of the men and women who supported the Union after Alabama's secession faced great difficulties. Many were ostracized and ridiculed by neighbors, called before community vigilance committees for questioning and intimidation, or actually harmed for endorsing the Union. Such treatment was most commonly meted out to those who publicly asserted their views; those who kept quiet and did not interfere with volunteering were often left alone during the first year of the war. After Confederate conscription began in April 1862, however, community tolerance of Unionists waned. Individuals who resisted the draft, for whatever reason, were subject to arrest and imprisonment. Family members who supported resisters were frequently threatened with violence or exile by conscript cavalry who hoped to pressure men to come in from the woods or mountains and surrender. In addition, it was not at all uncommon for the families of Unionists to be targeted for punitive foraging or arson by Confederate forces or local conscript cavalry.
After the Union Army invaded Alabama in early 1862, Unionists had more opportunities to flee behind Union lines for safety and the possibility of employment as soldiers, spies, or laborers. Most well known of Alabama's Union troops was the First Alabama Cavalry, U.S.A., organized in late 1862 by Brig. Gen. Grenville M. Dodge, stationed at Corinth, Mississippi. The regiment served mostly in northern Alabama, western Tennessee, and northeastern Mississippi, though it marched with Gen. William Tecumseh Sherman to Savannah in 1864. Alabama Unionists also joined other federal regiments, particularly those from Tennessee, Indiana, Illinois, and Ohio. Those who remained at home, both within Union-occupied territory and behind Confederate lines, also actively assisted Union forces as spies and guides. In some cases, they collaborated with local African Americans (most often their own slaves) to aid and abet the Union Army or pro-Union men in their neighborhoods. Moreover, African Americans from Alabama also crossed the Union lines to serve as laborers and soldiers, and after the Emancipation Proclamation went into effect in 1863, many were inducted into United States Colored Troops regiments. Almost 5,000 African Americans, or 6 percent of Alabama's black male population between the ages of 18 and 45, volunteered in the Union ranks.
As was the case throughout the South, by the midpoint of the war Alabama's original Unionists were increasingly joined in their dissent by deserters from the Confederate Army, mostly men whose families were struggling at home without their labor. Disillusioned by the realities of warfare, angered by the inequities of service under laws exempting slaveowners and selected professionals, such Alabamians generally wanted the war to end more than they desired Union victory, though some did cross lines and join the Union army rather than desert and avoid service altogether. A small peace movement also emerged at this time among men who had originally opposed secession but later supported the state.
After the war, Unionists continued to struggle politically and socially, for their wartime activities had alienated them from
their now-defeated neighbors. Most eagerly joined the Union League and the Republican Party. Some wartime Unionists helped reintroduce the Methodist-Episcopal Church (as contrasted with the Methodist-Episcopal Church, South) to northern Alabama, finding there a more hospitable environment
for worship. Many campaigned strenuously to convince the president and Congress to limit the political rights of former Confederates.
They also sought positions of local and state authority for others who had supported the Union during the war. At this point,
a number of men who had originally opposed secession but supported the state in 1861, as well as citizens who had become disillusioned
with the war, also moved to the fore of political life in Alabama. These moderates were, in general, encouraged by Pres. Andrew Johnson, who appointed such men to
positions of political authority in the immediate post-war provisional governments he established. The Republican Party in
Alabama was populated by such individuals, as well as core Unionists who had served in the Union Army or otherwise actively
resisted the Confederacy. Both groups were referred to by their Democratic opponents as sc alawags.
Under Congressional Reconstruction (1867-74) wartime loyalists gained greater political power than they had under Presidential Reconstruction, taking leading roles in the constitutional convention of 1867, the Freedmen's Bureau, and the Republican-dominated state legislature. Most also supported, though sometimes reluctantly, voting rights for African Americans as a means to gain political power over former Confederates. For their continued association with northern Republicans and support for African American equality, white Unionists were targeted for intimidation and physical violence by the Ku Klux Klan and other anti-Reconstruction vigilantes. As elsewhere in the South, Alabama Unionists and their Republican allies (white and black, northern and southern) received little in the way of federal assistance to defend against the onslaught of violence. As their party was overwhelmed by the Democratic opposition, Unionists retreated from the forefront of state politics, though those in communities with substantial loyalist populations continued in positions of local political leadership well into the late nineteenth century.
Barney, William L. The Secessionist Impulse: Alabama and Mississippi in 1860. Princeton: Princeton University Press, 1974.
Fitzgerald, Michael W. The Union League Movement in the Deep South: Politics and Agri cultural Change During Reconstruction. Baton Rouge: Louisiana State University Press, 1989.
Mills, Gary B. Southern Loyalists in the Civil War: The Southern Claims Commission. A Composite Directory of Case Files Created by the U.S. Commissioner of Claims, 1871-1880, including those appealed to the War Claims Committee of the U.S. House of Representatives and the U.S. Court of Claims. Baltimore: Genealogical Publishing Company, Inc. 1994.
Rogers, William Warren, Jr. The Confederate Home Front: Montgomery During the Civil War. Tuscaloosa: The University of Alabama Press, 1999.
Storey, Margaret M. Loyalty and Loss: Alabama's Unionists in the Civil War and Reconstruction. Baton Rouge: Louisiana State University Press, 2004.
Margaret M. Storey
Published December 14, 2007
Last updated October 3, 2011
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Uveitis is inflammation of the uvea, which is made up of the iris, ciliary body and choroid. Together, these form the middle layer of the eye between the retina and the sclera (white of the eye).
The eye is shaped like a tennis ball, with three different layers of tissue surrounding the central gel-filled cavity, which is called the vitreous. The innermost layer is the retina, which senses light and helps to send images to your brain. The outermost layer is the sclera, the strong white wall of the eye. The middle layer between the sclera and retina is called the uvea.
The uvea contains many blood vessels — the veins, arteries and capillaries — that carry blood to and from the eye. Because the uvea nourishes many important parts of the eye (such as the retina), inflammation of the uvea can damage your sight.
There are several types of uveitis, defined by the part of the eye where it occurs.
- Iritis affects the front of your eye. Also called anterior uveitis, this is the most common type of uveitis. Iritis usually develops suddenly and may last six to eight weeks. Some types of anterior uveitis can be chronic or recurrent.
- If the uvea is inflamed in the middle or intermediate region of the eye, it is called pars planitis (or intermediate uveitis). Episodes of pars planitis can last between a few weeks to years. The disease goes through cycles of getting better, then worse.
- Posterior uveitis affects the back parts of your eye. Posterior uveitis can develop slowly and often lasts for many years.
- Panuveitis occurs when all layers of the uvea are inflamed.
Next Page: Uveitis Causes
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Marion Levine teaches English, Literature and Film Production at Los Angeles Center for Enriched Studies, Los Angeles, CA
Measure for Measure, Act 4 or 5
What's On for Today and Why
Students will choose a character from Measure for Measure and create a "back story" for that character. This will encourage students to read the text closely looking for clues regarding a specific character's history. Students will re-read a portion of the text and then write about what has happened to the character before the play begins. They will then create an artifact, such as a diary or journal entry, written by the charcacter they have selected. This will allow them the opportunity to think like the character and to view the events of the play from a specific point of view.
This lesson will take two 40 minute class periods.
What You Need
Measure for Measure, Folger Edition
What To Do
1. Explain the concept of a "back story" as the important events that occur to a character before the play begins. You may need to prompt students with questions such as:
What was the character like as a child?
In what situation did he/she grow up?
Students will need to show how the script supports their choices.
2. Have the students write a one or two page back story in either the first or third person.
3. Divide students into small groups of 4 or 5 and have them re-read Act 4 or Act 5, combing throught the text for character details.
4. Have students write a letter, diary or journal entry from their selected characters point of view (first person). This artifact should concern one or more characters in the play.
5. For increased authenticity, appropriate for an "Extra-Extended" book, students could write their letter, diary entry using calligraphy, a handwriting font or on a piece of yellowed paper.
6. Allow students time to read their pieces and share their artifacts with the class.
How Did It Go?
Were students able to justify their choices with reference to the text? Did their artifacts accurately portray character traits that can be interpreted from the text? Were students able to convey a sense of the character's perspective through this activity?
This lesson could be applied to any fictional text that the students read in class. Through close reading and attention to a specific character, students are able to identify with, and understand the concerns of a character on a deeper level. Possible choices could include Jay Gatsby, Hester Prynne,and Atticus Finch.
If you used this lesson, we would like to hear how it went and about any adaptations you made to suit the needs of YOUR students.
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Jim Lake and Maria Rivera, at the University of California-Los Angeles (UCLA), report their finding in the Sept. 9 issue of the journal Nature.
Scientists refer to both bacteria and Archaea as "prokaryotes"--a cell type that has no distinct nucleus to contain the genetic material, DNA, and few other specialized components. More-complex cells, known as "eukaryotes," contain a well-defined nucleus as well as compartmentalized "organelles" that carry out metabolism and transport molecules throughout the cell. Yeast cells are some of the most-primitive eukaryotes, whereas the highly specialized cells of human beings and other mammals are among the most complex.
"A major unsolved question in biology has been where eukaryotes came from, where we came from," Lake said. "The answer is that we have two parents, and we now know who those parents were."
Further, he added, the results provide a new picture of evolutionary pathways. "At least 2 billion years ago, ancestors of these two diverse prokaryotic groups fused their genomes to form the first eukaryote, and in the processes two different branches of the tree of life were fused to form the ring of life," Lake said.
The work is part of an effort supported by the National Science Foundation--the federal agency that supports research and education across all disciplines of science and engineering--to re-examine historical schemes for classifying Earth's living creatures, a process that was once based on easily observable traits. Microbes, plants or animals wer
Contact: Leslie Fink
National Science Foundation
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Mercury in the Morning
The planet Mercury -- the planet closest to the Sun -- is just peeking into view in the east at dawn the next few days. It looks like a fairly bright star. It's so low in the sky, though, that you need a clear horizon to spot it, and binoculars wouldn't hurt.
Mercury is a bit of a puzzle. It has a big core that's made mainly of iron, so it's quite dense. Because Mercury is so small, the core long ago should've cooled enough to form a solid ball. Yet the planet generates a weak magnetic field, hinting that the core is still at least partially molten.
The solution to this puzzle may involve an iron "snow" deep within the core.
The iron in the core is probably mixed with sulfur, which has a lower melting temperature than iron. Recent models suggest that the sulfur may have kept the outer part of the core from solidifying -- it's still a hot, thick liquid.
As this mixture cools, though, the iron "freezes" before the sulfur does. Small bits of solid iron fall toward the center of the planet. This creates convection currents -- like a pot of boiling water. The motion is enough to create a "dynamo" effect. Like a generator, it produces electrical currents, which in turn create a magnetic field around the planet.
Observations earlier this year by the Messenger spacecraft seem to support that idea. But Messenger will provide much better readings of what's going on inside Mercury when it enters orbit around the planet in 2011.
Script by Damond Benningfield, Copyright 2008
For more skywatching tips, astronomy news, and much more, read StarDate magazine.
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Black holes growing faster than expected
Black hole find Existing theories on the relationship between the size of a galaxy and its central black hole are wrong according to a new Australian study.
The discovery by Dr Nicholas Scott and Professor Alister Graham, from Melbourne's Swinburne University of Technology, found smaller galaxies have far smaller black holes than previously estimated.
Central black holes, millions to billions of times more massive than the Sun, reside in the core of most galaxies, and are thought to be integral to galactic formation and evolution.
However astronomers are still trying to understand this relationship.
Scott and Graham combined data from observatories in Chile, Hawaii and the Hubble Space Telescope, to develop a data base listing the masses of 77 galaxies and their central supermassive black holes.
The astronomers determined the mass of each central black hole by measuring how fast stars are orbiting it.
Existing theories suggest a direct ratio between the mass of a galaxy and that of its central black hole.
"This ratio worked for larger galaxies, but with improved technology we're now able to examine far smaller galaxies and the current theories don't hold up," says Scott.
In a paper to be published in the Astrophysical Journal, they found that for each ten-fold decrease in a galaxy's mass, there was a one hundred-fold decrease in its central black hole mass.
"That was a surprising result which we hadn't been anticipating," says Scott.
The study also found that smaller galaxies have far denser stellar populations near their centres than larger galaxies.
According to Scott, this also means the central black holes in smaller galaxies grow much faster than their larger counterparts.
Black holes grow by merging with other black holes when their galaxies collide.
"When large galaxies merge they double in size and so do their central black holes," says Scott.
"But when small galaxies merge their central black holes quadruple in size because of the greater densities of nearby stars to feed on."
Somewhere in between
The findings also solve the long standing problem of missing intermediate mass black holes.
For decades, scientists have been searching for something in between stellar mass black holes formed when the largest stars die, and supermassive black holes at the centre of galaxies.
"If the central black holes in smaller galaxies have lower mass than originally thought, they may represent the intermediate mass black hole population astronomers have been hunting for," says Graham.
"Intermediate sized black holes are between ten thousand and a few hundred thousand times the mass of the Sun, and we think we've found several good candidates."
"These may be big enough to be seen directly by the new generation of extremely large telescopes now being built," says Graham.
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Hoodoos may be seismic gurus
Hoodoo prediction Towering chimney-like sedimentary rock spires known as hoodoos may provide an indication of an area's past earthquake activity.
The research by scientists including Dr Rasool Anooshehpoor, from the United States Nuclear Regulatory Commission, may provide scientists with a new tool to test the accuracy of current hazard models.
Hoodoo formations are often found in desert regions, and are common in North America, the Middle East and northern Africa.
They are caused by the uneven weathering of different layers of sedimentary rocks, that leave boulders or thin caps of hard rock perched on softer rock.
By knowing the strengths of different types of sedimentary layers, scientists can determine the amount of stress needed to cause those rocks to fracture.
The United States Geological Survey (USGS) use seismic hazard models to predict the type of ground motion likely to occur in an area during a seismic event. But, according to Anooshehpoor, these models lack long term data.
"Existing hazard maps use models based on scant data going back a hundred years or so," says Anooshehpoor. "But earthquakes have return periods lasting hundreds or thousands of years, so there is nothing to test these hazard models against."
The researchers examined two unfractured hoodoos within a few kilometres of the Garlock fault, which is an active strike-slip fault zone in California's Red Rock Canyon.
Their findings are reported in the Bulletin of the Seismological Society of America.
"Although we can't put a precise age on hoodoos because of their erosion characteristics, we can use them to provide physical limits on the level of ground shaking that could potentially have occurred in the area," says Anooshehpoor.
The researchers developed a three-dimensional model of each hoodoo and determined the most likely place where each spire would fail in an earthquake.
They then tested rock samples similar to the hoodoo pillars to measure their tensile strength and compared their results with previously published data.
USGS records suggest at least one large magnitude earthquake occurred along the fault in the last 550 years, resulting in seven metres of slip, yet the hoodoos are still standing.
This finding is consistent with a median level of ground motion associated with the large quakes in this region, says Anooshehpoor.
"If an earthquake occurred with a higher level of ground motion, the hoodoos would have collapsed," he says.
"Nobody can predict earthquakes, but this will help predict what ground motions are associated with these earthquakes when they happen."
Dr Juan Carlos Afonso from the Department of Earth and Planetary Sciences at Sydney's Macquarie University says it's an exciting development.
"In seismic hazard studies, it's not just difficult to cover the entire planet, it's hard to cover even small active regions near populated areas," says Afonso.
"You need lots of instruments, so it's great if you can rely on nature and natural objects to help you."
He says while the work is still very new and needs to be proven, the physics seems sound.
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Science Fair Project Encyclopedia
The chloride ion is formed when the element chlorine picks up one electron to form the anion (negatively charged ion) Cl−. The salts of hydrochloric acid HCl contain chloride ions and are also called chlorides. An example is table salt, which is sodium chloride with the chemical formula NaCl. In water, it dissolves into Na+ and Cl− ions.
The word chloride can also refer to a chemical compound in which one or more chlorine atoms are covalently bonded in the molecule. This means that chlorides can be either inorganic or organic compounds. The simplest example of an inorganic covalently bonded chloride is hydrogen chloride, HCl. A simple example of an organic covalently bonded chloride is chloromethane (CH3Cl), often called methyl chloride.
Other examples of inorganic covalently bonded chlorides which are used as reactants are:
- phosphorus trichloride, phosphorus pentachloride, and thionyl chloride - all three are reactive chlorinating reagents which have been used in a laboratory.
- Disulfur dichloride (SCl2) - used for vulcanization of rubber.
Chloride ions have important physiological roles. For instance, in the central nervous system the inhibitory action of glycine and some of the action of GABA relies on the entry of Cl− into specific neurons.
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details
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Fun Classroom Activities
The 20 enjoyable, interactive classroom activities that are included will help your students understand the text in amusing ways. Fun Classroom Activities include group projects, games, critical thinking activities, brainstorming sessions, writing poems, drawing or sketching, and more that will allow your students to interact with each other, be creative, and ultimately grasp key concepts from the text by "doing" rather than simply studying.
1. A Year from Now
Where will Bone be and how will she be feeling a year from now? Write a one page description of Bone's life a year after the end of the book from Bone's perspective.
2. The Monster Within
When Bone's anger is described, it seems to grow and even take form. Take one of the descriptions for Bone's anger and rage and draw it.
3. Bone's Poetry
Write a poem as if you are Bone. The poem can be...
This section contains 555 words|
(approx. 2 pages at 300 words per page)
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What is bone cancer?
Bone is the framework that supports the body. Most bones are hollow. Bone marrow is the soft tissue inside hollow bones. The main substance of bone is made up of a network of fibrous tissue onto which calcium salts are laid down. This makes the bone very hard and strong. At each end of the bone is a softer bone-like tissue called cartilage that acts as a cushion between bones. The outside of the bone is covered with a layer of fibrous tissue.
The bone itself contains 2 kinds of cells. Osteoblasts are cells that form the bone. Osteoclasts are cells that dissolve bone. Although we think that bone does not change, the truth is that it is very active. New bone is always forming and old bone dissolving.
The marrow of some bones is only fatty tissue. In other bones the marrow is a mixture of fat cells and the cells that make blood cells. These blood-forming cells make red blood cells, white blood cells, and platelets.
Types of bone tumors
Most of the time when someone is told they have cancer in their bones, the doctor is talking about a cancer that started somewhere else and then spread to the bone. This is called metastatic cancer (not bone cancer). This can happen to people with many different types of advanced cancer, such as breast cancer, prostate cancer, lung cancer, and many others. Under a microscope, theses cancer cells in the bone look like the cancer cells that they came from. If someone has lung cancer that has spread to the bone, the cells there will look and act like lung cancer cells and they will be treated the same way.
To learn more about cancer that has spread to bone, please see the American Cancer Society document Bone Metastasis, as well as the document on the place where the cancer started (Breast Cancer, Lung Cancer (Non-Small Cell), Prostate Cancer, etc.).
Other kinds of cancers that are sometimes called “bone cancers” start in the bone marrow – in the blood-forming cells – not the bone itself. These are not true bone cancers. The most common of these is multiple myeloma. Certain lymphomas (which more often start in lymph nodes) and all leukemias start in bone marrow. To learn more about these cancers, refer to the document for each.
A primary bone tumor starts in the bone itself. True (or primary) bone cancers are called sarcomas. A sarcoma is a cancer that starts in bone, muscle, tendons, ligaments, fat tissue, or some other tissues in the body.
There are different types of bone tumors. Their names are based on the bone or tissue that is involved and the kind of cells that make up the tumor. Some are cancer (malignant). Others are not cancer (benign). Most bone cancers are called sarcomas.
Benign bone tumors do not spread to other tissues and organs. They can usually be cured by surgery. The information here does not cover benign bone tumors.
Bone tumors that are cancer (malignant)
Osteosarcoma: Osteosarcoma (also called osteogenic sarcoma) is the most common true bone cancer. It is most common in young people between the ages of 10 and 30. But about 10% of cases are people in their 60s and 70s. This cancer is rare during middle age. More males than females get this cancer. These tumors start most often in bones of the arms, legs, or pelvis. This type of bone cancer is not discussed in this document, but is covered in detail in our document, Osteosarcoma.
Chondrosarcoma: This is cancer of the cartilage cells. Cartilage is a softer form of bone-like tissue. Chondrosarcoma is the second most common true bone cancer. It is rare in people younger than 20. After age 20, the risk of this cancer keeps on rising until about age 75. Women get this cancer as often as men.
Chondrosarcomas can develop in any place where there is cartilage. It most often starts in cartilage of the pelvis, leg, or arm, but it can start in many other places, too.
Chondrosarcomas are given a grade, which measures how fast they grow. The lower the grade, the slower the cancer grows. When cancer grows slowly, the chance that it will spread is lower and the outlook is better. There are also some special types of chondrosarcoma that respond differently to treatment and have a different outlook for the patient. These special types look different when seen under a microscope.
Ewing tumor: This cancer is also called Ewing sarcoma. It is named after Dr. James Ewing, the doctor who first described it in 1921. It is the third most common bone cancer. Most Ewing tumors start in bones, but they can start in other tissues and organs. This cancer is most common in children and teenagers. It is rare in adults older than 30. This type of bone cancer is not discussed in this document, but is covered in detail in our document, Ewing Family of Tumors.
Malignant fibrous histiocytoma (MFH): This cancer more often starts in the soft tissues around bones (such as ligaments, tendons, fat, and muscle) rather than in the bone itself. If it starts in the bones, it most often affects the legs or arms. It usually occurs in older and middle-aged adults. MFH mostly tends to grow into nearby tissues, but it can spread to distant sites, like the lungs. (Another name for this cancer is pleomorphic undifferentiated sarcoma.)
Fibrosarcoma: This is another type of cancer that starts more often in “soft tissues” than it does in the bones. Fibrosarcoma usually occurs in older and middle-aged adults. Leg, arm, and jaw bones are most often affected.
Giant cell tumor of bone: This type of bone tumor has both benign (not cancer) and malignant forms. The benign form is most common. These don’t often spread to distant sites, but after surgery they tend to come back where they started. Each time they come back after surgery they are more likely to spread to other parts of the body. These tumors often affect the arm or leg bones of young and middle-aged adults.
Chordoma: This tumor usually occurs in the base of the skull and bones of the spine. It is found most often in adults older than 30. It is about twice as common in men than in women. Chordomas tend to grow slowly and usually do not spread to other parts of the body. But they often come back in the same place if they are not removed completely. When they do spread, they tend to go to the lymph nodes, lungs, and liver.
Last Medical Review: 12/05/2012
Last Revised: 01/24/2013
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In the American electoral system, a primary election is an election that determines the nominee for each political party, who then competes for the office in the general election. A presidential primary is a state election that picks the delegates committed to nominate particular candidates for president of the United States. A presidential caucus, as in Iowa, requires voters to meet together for several hours in face-to-face meetings that select county delegates, who eventually pick the delegates to the national convention. No other country uses primaries; they choose their candidates in party conventions.
Primaries were introduced in the Progressive Era in the early 20th century to weaken the power of bosses and make the system more democratic. In presidential elections, they became important starting in 1952, when the first-in-the-nation New Hampshire Primary helped give Dwight D. Eisenhower the Republican nomination, and knocked Harry S. Truman out of the Democratic race because of his poor showing. In 1964, Lyndon B. Johnson ended his reelection campaign after doing poorly in New Hampshire.
After 1968, both parties changed their rules to emphasize presidential primaries, although some states still use the caucus system.
In recent decades, New Hampshire holds the first primary a few days after Iowa holds the first caucus. That gives these two states enormous leverage, as the candidates and the media focus there. New Hampshire and Iowa receive about half of all the media attention given all primaries.
The primary allows voters to choose between different candidates of the some political parties, perhaps representing different wings of the party. For example, a Republican primary may choose between a range of candidates from moderate to conservative. Gallup's 2008 polling data indicated a trend in primary elections towards more conservative candidates, despite the more liberal result in the general election.
In recent years the primary seasons has come earlier and earlier, as states move up to earlier dates in the hope it will give them more leverage. For example, Barry Goldwater won the 1964 nomination because he won the last primary in California. The logic is faulty--in highly contested races the later primaries have more leverage. Thus in 2008 California gave up its traditional last-in-the-nation role and joined 20 other states on Super Tuesday. Neither the candidates not the voters paid it much attention. Michigan and Florida moved up their primaries in defiance of national Democratic Party rules and were penalized. The result is the primary season is extended, and is far more expensive, and no state gets an advantage--except for Iowa and New Hampshire, which now have dates in early January.
In late 2009 the two national parties are meeting to find a common solution.
- Duncan, Dayton. Grass roots: one year in the life of the New Hampshire presidential primary (1991) 436 pages; on 1988 campaign
- Johnson, Haynes, and Dan Balz. The Battle for America 2008: The Story of an Extraordinary Election (2009), excellent history of 2008 primaries
- Kamarck, Elaine C. Primary Politics: How Presidential Candidates Have Shaped the Modern Nominating System (2009) excerpt and text search
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Learning is the means whereby we acquire new working knowledge about the world. Memory is the means whereby we retain that knowledge over time. Our abilities to learn and remember are essential to our sense of self and our ability to function effectively in daily life. Memory is the glue that holds our mental life together. As a result, we are who we are in large part because of what we have learned and what we remember from past experience.
But what is memory? How does the brain capture and sustain it? Why does memory sometimes fail us? Those simple questions, of course, have exceedingly complex answers, and many biological details about the process of memory in humans and other animals remain unknown.
HHMI investigator Eric R. Kandel of Columbia University, however, has provided a good start. His studies of the molecular basis of learning and memory underpin much of what we know about how events are recorded by the brain, processed by individual nerve cells, and etched in gray matter. For his work on learning and memory, Kandel was awarded a share of the 2000 Nobel Prize in Physiology or Medicine.
In the 1960s, Kandel began his studies of learning and memory by focusing on the behavior of the sea slug Aplysia, which he found to be a marvelously tractable system in which to study the cellular basis of these abilities. With only about 20,000 nerve cells — compared with the roughly thousand billion in humans — and a well-delineated neural circuitry, it proved possible to zero in on a biologically interesting reflex pathway. Like humans and other animals, Aplysia is capable of learning to modify this reflex, and this learning involves making memories.
Kandel found that the cellular basis for memory depends on persistent changes in synapses, the connections between nerve cells. The differences in the strength of these connections come about through learning. Kandel found that when, in the simple withdrawal reflex, the gill reacts to touch, the connection between the sensory nerve cell and motor nerve cell of the reflex are activated. When the sea slug was taught to ignore a harmless touch, the connections between the sensory nerve cell and motor cell weakened. When the same light touch was coupled to an unpleasant fearful stimulus the animal became sensitized. It would now react strongly to the light touch because the same set of connections had strengthened.
Kandel later discovered that short-term memory is kindled by the modulation of synapses and that long-term memory is sustained by the activation of genes. The formation of memories, Kandel determined, is a function of biochemical changes that occur at the synapse. To make short-term memories, the proteins involved in a chain of events at the nexus of nerve cells are chemically altered by the addition of phosphate groups. To cement a memory for the long haul, proteins are added at the synapse to make new connections with sensitization and lose connections with habituation.
In the 1990s, he turned from studying simple forms of learning to more complex forms using genetically modified mice and showed that similar principles for short and long term memory were at work here as well.
By laying a foundation for understanding the events that shape our ability to learn and remember, Kandel's work has helped us understand not only the cellular processes that occur during the acts of learning and remembering, but also - through his work on mice - where things can go wrong when dementia and other illnesses that affect memory arise. The cellular processes revealed by Kandel are among the targets of drugs used to alleviate these disorders of memory. Pinpointing the activity of individual nerve cells engaged in the process of learning and memory may help in the development of new, more effective agents to treat diseases that affect the brain.
Photo: Matthew Septimus
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The Matter at Issue: The Throne of France
The Hundred Years War was fought largely over who would be the king of France. The English kings, who had originally been French nobles that invaded and conquered England in 1066, still held lands in France. The English lands in France had long been viewed uncomfortably by the French king. Through the 13th century, strong French kings had reclaimed French lands held by the English kings. By the early 14th century, three events came together. First, the English kings noted that one more push by the French would deive the English completely out of France. Second, the French were entering a period of weak kings. Third, the English throne was now occupied by the young, vigorous, able and (ultimately) long lived Edward III. In any other circumstances it would appear absurd for the English king to come up with the idea of claiming the French throne in order to protect English lands in France. But Edward III was bold and, in one of those uniquely Medieval ironies, he had law and custom on his side. The English claim to the French throne was strong, as were the English armies and Edward IIIs resolve. The resulting war outlived Edward, and his great grandson, Henry V, came within a hair of actually taking the French throne.
The items below explain the situation in rather more detail.
Historical Kings of France
Historical Kings of England
The English Position of the Throne of France
The French Ultimatum
A Summary of Overlapping Claims to Various Thrones
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Like the Republican party, the Democratic party also cracked beneath the weight of the issues at hand. States that favored slavery in the territories walked out of the Democratic convention at Charleston, preventing nominee Stephen Douglas from winning the party endorsement. A reconvened convention eventually nominated Douglas, but kept territory slavery out of the platform altogether.
As a result of disagreements over the issue of slavery, splinter parties formed. The Southern Democratic Party spun off from traditional Democrats to nominate John Breckenridge, an advocate of slavery in the West. Republican breakaways formed the Constitutional Union Party. They nominated John Bell who would not address the issue of slavery at all, but rather spoke of upholding the Constitution.
With four candidates in the race, Lincoln won the 1860 election. But by the time he took office in March of 1861, seven southern states had already seceded from the Union. When the first shot rang out at Fort Sumter, just one month after Lincoln took office, the Civil War began. Lincoln's hopes for peacefully preserving the union were dashed. In 1863, Lincoln issued the Emancipation Proclamation. He also promoted a Constitutional Amendment to permanently abolish slavery. These bold steps marked a shift from Lincoln's more moderate campaign position on slavery issues. They also shifted the focus of the war from preserving the union to freeing the slaves.
Remarkably, the election of 1864 was not suspended during the bloody Civil War. Union soldiers were given absentee ballots or furloughed to permit them to vote. With mounting Union victories, the votes of soldiers and the campaign slogan, "Don't switch horses in mid-stream," Lincoln won the election. Sadly, as this 1864 campaign song strangely foreshadows, Lincoln did not live to see passage of the 13th Amendment that abolished slavery forever. He was assassinated just five days after Ulysses S. Grant celebrated victory over Robert E. Lee at Appomattox.
Lincoln's presidency causes one to wonder:
- Why he changed his position on the issue of abolition during his presidency?
- Whether these changes might affect the way we view his original platform?
- What were Lincoln's priorities when he created his original platform? How did the advent and progress of the war affect these priorities?
- To what extent did Lincoln's original platform represent his personal views? To what extent did it reflect a desire and strategy to win the presidency?
- If YOU were running for president, how would you balance your own opinions with the need to appeal to party and popular opinion?
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The following information was extracted from the publication "Threatened"
produced by BNZ in cooperation with the Department of Conservation
and Royal Forest and Bird Protection Society.
The Predation Threat
In 1987, a dog was on the loose in Waitangi State forest in the Bay of Islands. For six weeks it rampaged through the forest killing every kiwi it encountered. By the time the dog was found, perhaps as many as 500 of the 1000 kiwi living there had been slaughtered. This carnage at Waitangi illustrates just how vulnerable the kiwi is to predators and the speed at which seemingly healthy populations can fail.
Other predators introduced to New Zealand by humans may cause similar havoc. The main threat to the kiwi is posed by: Possums, stoats, ferrets, and feral (wild) cats who steal eggs and kill young. Larger predators include pigs and dogs.
Young kiwi leave the nest at just three weeks of age, weighing only 200g. Small and slow, they are easy prey. Very few survive this precarious journey from birth to 12 months, when they reach the critical size that enables them to stand up to most predators.
Humans, primarily through destroying forests and introducing predators in the first place, pose the single greatest threat to the kiwi. Ironically, we are also their greatest hope.
The kiwi is a one-off evolutionary design, holding all sorts of biological records. New Zealand's ancient isolation and lack of mammals allowed it to occupy a habitat and lifestyle that everywhere else in the world would be occupied by a mammal.
Whereas birds traditionally depend on sight, the kiwi is one of the few birds with a highly developed sense of smell. You can sometimes hear them sniffing around in the dark. Alarm them during the day and they will run off. Then, at a distance, just like a wolf or other mammal, they'll stick their bill (nose) in the air, sniffing to see if they are safe from pursuit.
Other reasons the kiwi could pass for a mammal is its loose, hair-like feathers, its long whiskers, the fact it can't fly and that it burrows in the ground.
Other kiwi curiosities include:
Being the only known bird to have external nostrils at the end of its bill. It literally sniffs out its food a bill-length below the surface.
It's huge eggs. The kiwi has one of the largest egg-to-body weight ratio of any bird. The mature egg averages 20% of the female's body weight. Compare that to 2% for an ostrich!
Being the smallest living member of the ratite family (which includes ostriches and emus).
They live in pairs — as monogamous couples — for most, if not all of their lives.
Sex role reversal: The female is bigger and dominates the male.
In some varieties, the male does most of the incubating of the eggs.
The eggs take an exceedingly long time to hatch — up to 80 days.
Kiwi tend to live in pairs, forming monogamous couples. These bonds are generally till death and have been known to last over 30 years. About every third day, the pair will shelter in the same burrow together. The relationship tends to be quite volatile and physical, the female generally calling the shots over her smaller partner.
During the night, as they are out foraging for food or patrolling their territory, they will perform duets, calling to each other. The female has a lower hoarser call than the male.
From the outside, it doesn't appear that kiwi domestic life is bliss. But the bond is long-lasting.
There are few surprises in the kiwi diet. It's mostly earthworms, spiders, fallen fruits and seeds, larvae of beetles and cicada and a mixture of forest invertebrates. But they will also take large food items like freshwater crays and even frogs. In captivity, kiwi have fished eels out of a pond, subdued them with a few thuds and eaten them.
Kiwi are extremely territorial birds, They protect their patch — which can be as much as 40 hectares — by calling or, if that fails, by chasing the intruder kiwi and giving it a good booting over. Very occasionally, kiwi kill each other fighting for territory.
Acutely aware of neighbours, they will often engage in calling duels. If a bird is intruding into another's space, it will rush back at full speed into its own space before returning a neighbour's call.
A gathering of kiwi is a rarity. However, on Stewart Island, they do live in small, mixed aged family groupings.
Kiwi Nests, er, Burrows!
Kiwi are burrowers. They may quickly clear a burrow at the end of a night's work, crash there during the day and then move on to a new burrow the next day.
Great Spotted Kiwi prefer dens. Unlike the Little Spotted Kiwi and the Brown Kiwi, who tends towards simple one-entrance burrows, the Great Spotted will put the time and effort into constructing a labyrinth of tunnels several metres long with more than one exit.
Common Kiwi Myths
Kiwi experts are keen to dispel myths surrounding the kiwi — particularly that they are half-blind and bumbling.
Here are a few common ones:
Myth: "Kiwi fight with their beaks."
To use their beaks to fight would be like head-butting someone with your nose.
At the end of the beak are the kiwi's external nostrils. Finely tuned and capable of detecting a few parts per million of scent, the beak, when probing the ground, can detect worms and other food.
Myth: "Kiwi are cute, gentle little creatures."
They are actually super-strong and often extremely bad tempered. The adults can look after themselves using their razor sharp claws as weapons. A couple of slashes can quickly draw blood — as conservationists have often found when putting their hands down kiwi burrows.
Because they are so aggressive, DOC staff can attract them simply by imitating their call. Incensed that another kiwi is on their turf, the response is instant and dramatic:
"It's amazing to hear them coming to kick the intruder out. They sound like a deer charging, almost exploding, through the dark. Standing there, it's quite intimidating. I guess it's part of the threat display."
"Pete" is a Great Spotted Kiwi in West Northland. "We've just got to walk into his territory and he comes catapulting in for a hit-and-run. He belts you in the leg and then runs off into the undergrowth. I think he views us as super-big kiwi. He's probably given some trampers a helluva scare."
Myth: "Kiwi are a bit thick."
According to Conservation Officers who know them best, they are capable of learning quickly and altering behaviour in the light of experience.
Myth: "Kiwi move slowly."
Superbly adapted to their natural habitat, the kiwi is extremely agile and quick moving. A kiwi can cover his territory — possibly the size of 60 football fields — in a night. This might take in three valley streams and all sorts of obstacles.
Myth: "Kiwi and half-blind."
The notion of their being half-blind probably stems from their being nocturnal and having small eyes. In fact, as Conservation Officers can testify, if you chase them at night, they can run very fast, swerving around trees and expertly navigating the undergrowth. Similarly, they are unfazed by daylight.
Kiwi Culture -- From a Maori Perspective
The Maori people have a very personal interest in seeing the kiwi survive and flourish.
According to many Maori traditions, the kiwi is the oldest of all Tanemahuta's bird family. It was Tane, the god of the forest who, with different wives, created much of the natural world, including birds, trees, stones and humans.
For Maori, kiwi are, in effect, our elder siblings. And, like a good older brother or sister, they are very protective of us. That's partly why they patrol the forests nightly.
Kiwi -- Six Unique Varieties
There are six identified varieties of kiwi.
The Little Spotted Kiwi
The smallest (about the size of a bantam) and most endangered species, the "Little Spots" have a very mellow, often docile nature. They have suffered terrible that the hands of possums, stoats, cats and larger predators.
Now extinct on mainland New Zealand, the largest remaining population is on Kapiti Island where 1000 birds occupy some 1900 ha of mixed forest, scrub and grassland. Sensitive management by DoC and the Maori Trustees of private land on Kapiti are ensuring that cats, dogs and other kiwi predators don't reach the island.
The Great Spotted Kiwi
The rugged mountaineer of the kiwi — found primarily in the high, often harsh hill country — the Great Spotted has forged a strange deal with evolution. The same harsh environment that makes it struggle from one day to the next also makes it tough going for the pigs, dogs and stoats that would otherwise be keen to pursue it.
Big bold and handsome, it is found only in the South Island, mainly in North West Nelson, Central Westland and Eastern Canterbury.
The North Island Brown Kiwi
Bug noses and short tempers is one way to sum up the Brown Kiwi. They are little toughies ... and have to be to survive against humans, introduced predators and the natural challenges of their often harsh bush existence.
The North Island Brown Kiwi is found only in the upper two-thirds of the North Island. They are widespread in Northland in a diverse range of vegetation types including exotic forests and rough farm land.
Okarito Brown Kiwi
In one sense, the new kid on the block. It was only in 1993 that the Okarito Brown, living in lowland forest just north of Franz Josef was identified as a distinct variety of kiwi. Tell-tale signs are its slightly greyish plumage sometimes accompanied by white facial feathers.
Squat and round and bigger than their northern Brown Kiwi cousins, they can grow to almost the same size as Great Spotted Kiwi. The Southern Tokoeka are found in Fiordland and on Stewart Island. They are the most communal of the somewhat reclusive kiwi.
The Haast Tokoeka, found in the rugged mountains behind Haast, was also identified as a distant variety of Kiwi in 1993. They spend their summers in the high sub alpine tussock grasslands but probably retreat to the lowland forests in winter.
Kiwi Sightings -- Where You Can See Kiwi
Few of us get the chance to see a kiwi in the wild but Brown Kiwi can be seen at the following places:
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Too many of our young people are caught up in conflicts every day that they do not know how to manage -- teasing, jealousy, and physical aggression. Juvenile delinquency and violence are symptoms of youth's inability to manage conflict in their lives. Teaching youth how to manage conflict in a productive way can help reduce incidents of violent behavior. Conflict resolution education is a beneficial component of a comprehensive violence prevention and intervention program in schools and communities.
Conflict resolution education encompasses problem solving in which the parties in dispute express their points of view, voice their interests, and find mutually acceptable solutions. Conflict resolution education programs help the parties recognize that while conflict happens all the time, people can learn new skills to deal with conflict in nonviolent ways. The programs that appear to be most effective are comprehensive and involve multiple components such as the problem-solving processes and principles of conflict resolution, the basics of effective communication and listening, critical and creative thinking, and an emphasis on personal responsibility and self-discipline.
Effective conflict resolution education programs can:
Four Common Strategies for Approaching Conflict Resolution
Experts identify four school-based conflict resolution strategies that can be replicated in other settings. These are commonly referred to as: (1) Peer Mediation, (2) Process Curriculum, (3) Peaceable Classrooms, and (4) Peaceable Schools. In all four approaches, conflict resolution education is viewed as giving youth nonviolent tools to deal with daily conflicts that can lead to self-destructive and violent behaviors. It is up to each local school district to decide how conflict resolution education will be integrated into its overall educational environment. The expectation is that when youth learn to recognize and constructively address what takes place before conflict or differences lead to violence, the incidence and intensity of that situation will diminish.
The program examples provided below empower young people with the processes and skills of conflict resolution. However, youth need to know that conflict resolution does not take precedence over adult responsibility to provide the final word in a variety of circumstances or situations. Conflict resolution has a place in the home, school, and community, but it can only supplement, not supplant, adult authority.
1) Peer Mediation Approach
Recognizing the importance of directly involving youth in conflict resolution, many schools and communities are using the Peer Mediation approach. Under this approach, specially trained student mediators work with their peers to resolve conflicts. Mediation programs reduce the use of traditional disciplinary actions such as suspension, detention, and expulsion; encourage effective problem solving; decrease the need for teacher involvement in student conflicts; and improve school climate.
An example of a Peer Mediation program is We Can Work It Out, developed by the National Institute for Citizenship Education in the Law and the National Crime Prevention Council. The program promotes mediation, negotiation, or other non-litigating methods as strategies to settle unresolved confrontations and fighting.
One Albuquerque elementary school principal reported, "We were having 100 to 150 fights every month on the playground before we started the New Mexico Center for Dispute Resolution's Mediation in the Schools Program. By the end of the school year, we were having maybe 10 (fights)." Other elementary schools using the same Peer Mediation approach to conflict resolution education reported that playground fighting had been reduced to such an extent that peer mediators found themselves out of a job.
Process Curriculum Approach
Teachers who devote a specific time -- a separate course, a distinct curriculum, or a daily lesson -- to the principles, foundation abilities, and problem-solving processes of conflict resolution are implementing the Process Curriculum approach. The Program for Young Negotiators, based on the Harvard Negotiation Project, is representative of this approach. Participating students, teachers, and administrators are taught how to use principled negotiation to achieve goals and resolve disputes. This type of negotiation helps disputants envision scenarios and generate options for achieving results that satisfy both sides.
In a North Carolina middle school with more than 700 students, conflict resolution education was initiated. The school used the Peace Foundation's Fighting Fair curriculum and a combination of components from various conflict resolution projects. After a school year, in-school suspensions decreased from 52 to 30 incidents (a 42-percent decrease), and out-of-school suspensions decreased from 40 incidents to 1 (a 97-percent decrease).
Peaceable Classroom Approach
The Peaceable Classroom approach integrates conflict resolution into the curriculum and daily management of the classroom. It uses the instructional methods of cooperative learning and "academic controversy." The Educators for Social Responsibility curriculum, Making Choices About Conflict, Security, and Peacemaking, is a peaceable classroom approach to conflict resolution. The program shows teachers how to integrate conflict resolution into the curriculum, classroom management, and discipline practices. It emphasizes opportunities to practice cooperation, appreciation of diversity, and caring and effective communication. Generally, peaceable classrooms are initiated on a teacher-by-teacher basis into the classroom setting and are the building blocks of the peaceable school.
Studies on the effectiveness of the Teaching Students To Be Peacemakers program, a Peaceable Classroom approach to conflict resolution, show that discipline problems requiring teacher management decreased by approximately 80 percent and referrals to the principal were reduced to zero.
Peaceable School Approach
The Peaceable School approach incorporates the above three approaches. This approach seeks to create schools where conflict resolution has been adopted by every member of the school community, from the crossing guard to the classroom teacher. A peaceable school promotes a climate that challenges youth and adults to believe and act on the understanding that a diverse, nonviolent society is a realistic goal.
In creating the Peaceable School Program of the Illinois Institute for Dispute Resolution, students are empowered with conflict resolution skills and strategies to regulate and control their own behavior. Conflict resolution is infused into the way business is conducted at the school between students, between students and teachers and other personnel, between teachers and administrators, and between parents and teachers and administrators.
In an evaluation of the Resolving Conflict Creatively Program in four multiethnic school districts in New York City, teachers of the Peaceable School approach to conflict resolution reported a 71-percent decrease in physical violence in the classroom and observed 66 percent less name calling and fewer verbal insults. Other changes in student behavior reported by the teachers included greater acceptance of differences, increased awareness and articulation of feelings, and a spontaneous use of conflict resolution skills throughout the school day in a variety of academic and nonacademic settings.
The effective conflict resolution education programs highlighted above have helped to improve the climate in school, community and juvenile justice settings by reducing the number of disruptive and violent acts in these settings; by decreasing the number of chronic school absences due to a fear of violence; by reducing the number of disciplinary referrals and suspensions; by increasing academic instruction during the school day; and by increasing the self-esteem and self-respect, as well as the personal responsibility and self-discipline of the young people involved in these programs.
Young people cannot be expected to promote and encourage the peaceful resolution of conflicts if they do not see conflict resolution principles and strategies being modeled by adults in all areas of their lives, such as in business, sports, entertainment, and personal relationships. Adults play a part in making the environment more peaceful by practicing nonviolent conflict resolution when minor or major disputes arise in their daily lives.
(Information provided by the U.S. Department of Education.)
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A tracheostomy (TRA-ke-OS-to-me) is a surgically made hole that goes through the front of your neck and into your trachea (TRA-ke-ah), or windpipe. The hole is made to help you breathe.
A tracheostomy usually is temporary, although you can have one long term or even permanently. How long you have a tracheostomy depends on the condition that required you to get it and your overall health.
To understand how a tracheostomy works, it helps to understand how your airways work. The airways carry oxygen-rich air to your lungs. They also carry carbon dioxide, a waste gas, out of your lungs.
The airways include your:
Air enters your body through your nose or mouth. The air travels through your voice box and down your windpipe. The windpipe splits into two bronchi that enter your lungs. (For more information, go to the Health Topics How the Lungs Work article.)
A tracheostomy provides another way for oxygen-rich air to reach your lungs, besides going through your nose or mouth. A breathing tube, also called a trach (trake) tube, is put through the tracheostomy and directly into the windpipe to help you breathe.
Doctors use tracheostomies for many reasons. One common reason is to help people who need to be on ventilators (VEN-til-a-tors) for more than a couple of weeks.
Ventilators are machines that support breathing. If you have a tracheostomy, the trach tube connects to the ventilator.
People who have conditions that interfere with coughing or block the upper airways also may need tracheostomies. Coughing is a natural reflex that protects the lungs. It helps clear mucus (a slimy substance) and bacteria from the airways. A trach tube can be used to help remove, or suction, mucus from the airways.
Doctors also might recommend tracheostomies for people who have swallowing problems due to strokes or other conditions.
Creating a tracheostomy is a fairly common, simple procedure. It's one of the most common procedures for critical care patients in hospitals.
The windpipe is located almost directly under the skin of the neck. So, a surgeon often can create a tracheostomy quickly and easily.
The procedure usually is done in a hospital operating room. However, it also can be safely done at a patient's bedside. Less often, a doctor or emergency medical technician may do the procedure in a life-threatening situation, such as at the scene of an accident or other emergency.
As with any surgery, complications can occur, such as bleeding, infection, and other serious problems. The risks often can be reduced with proper care and handling of the tracheostomy and the tubes and other related supplies.
Some people continue to need tracheostomies even after they leave the hospital. Hospital staff will teach patients and their families or caregivers how to properly care for their tracheostomies at home.
The NHLBI updates Health Topics articles on a biennial cycle based on a thorough review of research findings and new literature. The articles also are updated as needed if important new research is published. The date on each Health Topics article reflects when the content was originally posted or last revised.
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by I. Peterson
Unlike an ordinary, incandescent bulb, a laser produces light of a single wavelength. Moreover, the emitted light waves are coherent, meaning that all of the energy peaks and troughs are precisely in step.
Now, a team at the Massachusetts Institute of Technology has demonstrated experimentally that a cloud consisting of millions of atoms can also be made coherent. Instead of flying about and colliding randomly, the atoms display coordinated behavior, acting as if the entire assemblage were a single entity.
According to quantum mechanics, atoms can behave like waves. Thus, two overlapping clouds made up of atoms in coherent states should produce a zebra-striped interference pattern of dark and light fringes, just like those generated when two beams of ordinary laser light overlap.
By detecting such a pattern, the researchers proved that the clouds' atoms are coherent and constitute an "atom laser," says physicist Wolfgang Ketterle, who heads the MIT group. These matter waves, in principle, can be focused just like light.
Ketterle and his coworkers describe their observations in the Jan. 31 Science.
The demonstration of coherence involving large numbers of atoms is the latest step in a series of studies of a remarkable state of matter called a Bose-Einstein condensate. Chilled to temperatures barely above absolute zero, theory predicted, the atoms would collectively enter the same quantum state and behave like a single unit, or superparticle, with a specific wavelength.
First created in the laboratory in 1995 by Eric A. Cornell and his collaborators at the University of Colorado and the National Institute of Standards and Technology, both in Boulder, Bose-Einstein condensates have been the subject of intense investigation ever since (SN: 7/15/95, p. 36; 5/25/96, p. 327).
At MIT, Ketterle and his colleagues cool sodium atoms to temperatures below 2 microkelvins. The frigid atoms are then confined in a special magnetic trap inside a vacuum chamber.
To determine whether the atoms in the resulting condensate are indeed as coherent as photons in a laser beam, the researchers developed a novel method of extracting a clump of atoms from the trap.
In effect, they manipulate the magnetic states of the atoms to expel an adjustable fraction of the original cloud; under the influence of gravity, the released clump falls. The method can produce a sequence of descending clumps, with each containing 100,000 to several million coherent atoms.
The apparatus acts like a dripping faucet, Ketterle says. He and his colleagues describe the technique in the Jan. 27 Physical Review Letters.
To demonstrate interference, the MIT group created a double magnetic trap so that two pulses of coherent atoms could be released at the same time. As the two clumps fell, they started to spread and overlap. The researchers could then observe interference between the atomic waves of the droplets.
"The signal was almost too good to be true," Ketterle says. "We saw a high-contrast, very regular pattern."
"It's a beautiful result," Cornell remarks. "This work really shows that Bose-Einstein condensation is an atom laser."
From the pattern, the MIT researchers deduced that the condensate of sodium atoms has a wavelength of about 30 micrometers, considerably longer than the 0.04-nanometer wavelength typical of individual atoms at room temperature.
Ketterle and his colleagues are already planning several improvements to their primitive atom laser, including getting more atoms into the emitted pulses and going from pulses to a continuous beam.
Practical use of an atom laser for improving the precision of atomic clocks and for manipulating atoms is still distant, however, Cornell notes.
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The American Revolutionary War began in 1775 and ended in 1783. The British ruled the American colonists and they had become increasingly rebellious. General Gage had ordered 700 British soldiers to Concord to destroy a weapon's depot belonging to the colonists. On the way, they are met by some rebellious colonists and the British fire, killing eight Americans and wounding ten. This was known as ‘the shot heard round the world' and the war was on. The first major battle occurred on June 17, 1775 at Boston, Massachusetts. It was known as the Battle of Bunker Hill. The British are used to marching proudly out before taking aim and firing. The Americans have been ordered not to fire until they can see the whites of their eyes. They are dug in along the high ground of Breed's Hill. As the British close in, the Americans begin firing halting the advance. The British regroup and attack again. The same thing happens. By the third attack the Americans are out of ammunition and have to resort to stones and bayonets. Although the British take the hill, they've lost half their force with over a thousand casualties; the Americans have lost four hundred. On January 9, 1776, Thomas Paine's pamphlet, ‘Common Sense' criticizes King George III and encourages independence from Britain. It becomes a bestseller. By May, America has support from France and promises of support from Spain. After many battles, Congress formally endorses the Declaration of Independence on July 4, 1776. But the war isn't over yet. On July 14, 1777, Congress mandates an American flag consisting of thirteen stars and thirteen stripes to represent the thirteen colonies.
The first major American victory in the Revolutionary war occurs on October 7, 1777 at the Battle of Saratoga. There are six hundred British casualties to one hundred fifty American. On November 15, 1777, Congress adopts the Articles of Confederation giving Congress the sole authority of the new government. In February, France officially recognizes the United States. On March 16, 1778, a Peace Commission from Britain is sent to negotiate with the Americans. They offer to meet all demands, except independence. Congress rejects their offer. On July 10, 1778, France declares war against Britain. By now the British have instigated attacks on Americans by the native Indians. On May 12, 1780, the Americans suffered a major defeat as Charleston, South Carolina was captured by the British. On October 17, 1781, the British at Yorktown send out a flag of truce. On January 1, 1782, the British begin leaving America. On February 27, 1782, the House of Commons in England votes against further war with America. On August 27, 1872, the last battle is waged in South Carolina. On February 4, 1783, England officially declares an end to hostilities in America. On April 11, 1783, Congress officially declares an end to the Revolutionary war.
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This series enables children to use the computer for independent research into a range of curriculum related topics. They read the information from talking books and then link to writing grids so they can write about what they have read. High quality real speech gives added support on both the reading and writing activities. Perfect for the reading strand throughout the literacy curriculum!
This resource lets you find out about the different parts of a plant. Learn about plant habitats and some of the ways that plants are used by people. Use the information about growth and reproduction to write about pollination, fertilization, and seed dispersal.
"Find Out" information is presented in three levels of difficulty, designed to meet the needs of children with a wide range of abilities.
- Book One/Level One - The information is presented in short sentences. The associated writing grids enable children to work with sentence beginnings and endings to recreate the sentences from each information page.
- Book Two/Level Two - The information pages contain flowing text, and the writing grids offer a wider choice of words. This enables students to construct their own sentences.
- Book Three/Level Three - This level includes more in-depth information. The writing grids offer sentence starters and word banks than enable students to write an extended piece of text. Students use the keyboard as well as the grid as they interpret and respond to the text.
Find Out and Write About Series
Packed with rich multimedia content that is perfect for both literacy and subject teaching
The unique Find Out and Write About series for Clicker provides a range of multimedia CDs ideal for literacy teaching. Early readers of all ages can research the non-fiction material and then use the associated writing grids to write about what they have learnt.
A Find Out and Write About CD-ROM contains an interactive talking book of non-fiction text. Children can read the text or click the `listen` button to hear it spoken. Children can also click on a word with the right-hand mouse button to hear it.
Each page of the book contains a link to a Clicker writing grid that relates directly to that page, so children can write about the information they have just learned. Children write by clicking on a word with the left-hand mouse button. Words are colour-coded to help writers compose sentences successfully.
Emergent, struggling and fluent readers can all use the resources, as the information is provided at three differentiated levels. At level 1 for example, students are given short sentences, which they can choose to have read to them. The writing grids, relating directly to each page, enable students to work with sentence beginnings and endings. By Level 3, there is flowing in-depth information and the writing grid enables the student to interpret and respond to the text using the grid to scaffold their writing.
- Content-rich resources for both literacy and subject teaching
- Differentiated for children of all ages
- Listen to all text as real speech
- Printed outcome for monitoring by the teacher
- Hugely motivating for all ability levels
- Fully switch accessible for students with physical disabilities
- Great for whole class teaching with a whiteboard or touchscreen monitors, as well as individual work
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The Online Teacher Resource
Receive free lesson plans, printables, and worksheets by email:
- Over 400 Pages
- Great Writing Habits.
- Character Sketches, Plot Summaries
- Excellent for students
Age Range: Kindergarten through Grade 2 (Early Elementary or Primary Level)
Overview and Purpose : In this activity, students imagine what they would like to have fall from the sky every day and describe what happens when too much of it falls at once.
Objective: The student will be able to write a short story and draw a picture of what favorite item they would like to have fall from the sky every day.
Drawing paper/writing paper
Read Cloudy with a Chance of Meatballs to your students. Talk about what happened to the town. Have your students write a short story about what they would like to have fall from the sky everyday and what would happen if it got out of control. When they are finished writing, have them draw a picture of their story. Have the students share their stories with the class when they are finished.
This activity can also be done in small groups. The students can decide on one thing they would like to have fall from the sky and then tell their story.
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What is Rainwater Harvesting?
Rainwater harvesting is an ancient practice of catching and holding rain for later use. In a rainwater harvesting system, rain is gathered from a building rooftop or other source and is held in large containers for future use, such as watering gardens or washing cars. This practice reduces the demand on water resources and is excellent during times of drought.
Why is it Important?
In addition to reducing the demand on our water sources (especially important during drought), rainwater harvesting also helps prevent water pollution. Surprised?
Here’s why: the success of the 1972 Clean Water Act has meant that the greatest threat to New York’s waterbodies comes not from industrial sources, but rather through the small actions we all make in our daily lives. For example, in a rain storm, the oil, pesticides, animal waste, and litter from our lawns, sidewalks, driveways, and streets are washed down into our sewers. This is called non-point source (NPS) pollution because the pollutants come from too many sources to be identified. Rainwater harvesting diverts water from becoming polluted stormwater; instead, this captured rainwater may be used to irrigate gardens near where it falls.
In New York City, keeping rainwater out of the sewer system is very important. That’s because the city has an old combined sewer system that uses the same pipes to transport both household waste and stormwater to sewage treatment plants. During heavy rains, the system overloads; then untreated sewage and contaminated stormwater overflow into our rivers and estuary, with serious consequences:
Who is Harvesting Rainwater in New York City?
Back in 2002, a drought emergency pushed many community gardens to the brink of extinction. For the first time in twenty years, community gardeners were denied permission to use fire hydrants, the primary source of water for most community gardens. This crisis led to the formation of the Water Resources Group (WRG), an open collaboration of community gardening and environmental organizations. With help from the WRG, rainwater harvesting systems have now been built as demonstration sites in twenty NYC community gardens.
At community gardens that harvest rainwater, rain is diverted from the gutters of adjacent buildings and is stored in tanks in the gardens. A 1-inch rainfall on a 1,000-square-foot roof produces 600 gallons of water. The tanks are mosquito proof, so the standing water does not encourage West Nile virus. Because rainwater is chlorine free, it is better than tap water for plant growth, meaning healthier plants. And it’s free!
What are Other Cities Doing?
Many cities have adopted creative, low-cost ways to stop wasting rainwater by diverting it from their sewage systems and putting it to use where it falls. Here are some examples:
What Can I Do?
Spread the word! Educate those around you on the importance of lifestyle decisions.
Tell people not to litter, dump oil down storm drains, or overfertilize their lawns.
Install a rainwater harvesting system at your home, school, business, or local community center.
Contact your local elected officials, and let them know you support rainwater harvesting!
Supporting rainwater harvesting Jade Boat Loans
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July 31, 1998
Explanation: Do you recognize the constellation Orion? This striking but unfamiliar looking picture of the familiar Orion region of the sky was produced using survey data from the InfraRed Astronomical Satellite (IRAS). It combines information recorded at three different invisible infrared wavelengths in a red, green, and blue color scheme and covers about 30x24 degrees on the sky. Most of Orion's visually impressive stars don't stand out, but bright Betelgeuse does appear as a small purplish dot just above center. Immediately to the right of Betelgeuse and prominent in the IRAS skyview, expanding debris from a stellar explosion, a supernova remnant, is seen as a large bright ring-shaped feature. The famous gas clouds in Orion's sword glow brightly as the yellow regions at the lower right. No longer operational, IRAS used a telescope cooled by liquid helium to detect celestial infrared radiation.
Authors & editors:
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.
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Combined Gas Law
The Combined Gas Law combines Charles Law, Boyle s Law and Gay Lussac s Law. The Combined Gas Law states that a gas pressure x volume x temperature = constant.
Alright. In class you should have learned about the three different gas laws. the first one being Boyle's law and it talks about the relationship between pressure and volume of a particular gas. The next one should be Charles law which talks about the volume and temperature of a particular gas. And the last one should be Gay Lussac's law which talks about the relationship between pressure and temperature of a particular gas. Okay. But what happens when you have pressure, volume and temperature all changing? Well, we're actually going to combine these gas laws to form one giant gas law called the combined gas law. Okay.
If you notice then these three gas laws the pressure and volume are always in the numerator. So we're going to keep them on the numerator. p1v1. And notice the temperature is in the denominator over t1. So all these things are just squished into one and then p2v2 over t2. Okay. So this is what we're going to call the combined gas law. So let's actually get an example and do one together.
Alright, so I have a problem up here that says a gas at 110 kilo pascals and 33 celsius fills a flexible container with an initial volume of two litres, okay? If the temperature is raised to 80 degrees celsius and the pressure is raised to 440 kilo pascals, what is the new volume? Okay. So notice we have three variables. We're talking about pressure, temperature and volume. Okay, so now we're going to employ this combined gas law dealing with all three of these variables. So we're going to look at our first, our first number 110 kilo pascals and that's going to, that is the unit of pressure. So we know that's p1. Our p1 is 110 kilo pascals, at 30 degree celsius. I don't like things with celsius so I'm going to change this to kelvin. So I'm going to add 273 to that which makes it 303 kelvin. That's our temperature. And my initial volume is two litres so I'm going to say v1=2 litres. Okay then I continue reading. If the temperature is raised at 80 degree celsius, again we want it in kelvin, so we're going to add 273 making it to 353. So our t2 is 353 kelvin and the pressure increased to 440 kilo pascals, the pressure p2 is equal to 440 kilo pascals which I'm very happy that I kept it in kilo pascals that I kept it in kilo pascals. I've got to make sure these units are the same because pressure can be measured in several different units. I'm going to make sure all units are the same. And what is the new volume? So our v2 is our variable, what we're trying to find. Okay.
So let's basically plug all these variable in into our combined gas law to figure out what the new volume would be. Okay. So I'm going to erase this and say our pressure one is 110 kilo pascals. Our volume one is two litres. Our temperature one is 303 kelvin. Our pressure two is 440 kilo pascals. We don't know our volume so we're just going to say v2 over 353 kelvin. Okay. When I'm looking for a variable I'm going to cross multiply these guys. So I'm going to say 353 times 110 times 2 and that should give me seven, 77660, if you put that in a calculator. So I just cross multiply these guys. And I cross multiply these guys 303 times 440 times v2 gives me 133320v2. Okay, so then I want to get my, I want to isolate my variable, so I'm going to divide 133320. 133320. And I find that my new volume is 0.58. 0.58 metres. And that is how you do the combined gas law.
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Disease outbreaks, such as cholera, are commonly thought to happen after earthquakes and other natural disasters, but studies have found no evidence to support this. And the persistence of this belief may be hurting relief efforts.
The devastating earthquake in Haiti in January 2010 was followed by a deadly cholera outbreak. Many saw this as an inevitable outcome of the disaster, as poor sanitary conditions combined with numerous dead bodies and survivors housed in cramped quarters to produce an incubator for deadly diseases.
“It’s what all of us worried about when we arrived in Haiti just hours after the quake,” said NBC's Brian Williams, according to Popular Science. “Beyond the death toll, the inevitable spread of disease.”
However, a forensic analysis of the outbreak has shown that it had very little to do with either the earthquake or the conditions in Haiti afterwards.
The spread of the disease was traced back to a small military base, that was built years before, and its faulty sanitation system that allowed human fecal matter to pollute the nearby river. Analysis of the strain of Vibrio cholerae that swept through the Haitian population showed that it was identical to the one that was infecting people in Nepal, where some of the soldiers at the base were stationed before they joined the Haiti relief efforts.
[ More Geekquinox: Man maps out stunning Earth-like Mars ]
The problem with the belief in the 'inevitability' of the outbreak, according to what journalist and author Jonathan M. Katz wrote in his PopSci article, is "most journalists and responders shrugged off cholera as a natural product of the disaster. The attitude made epidemiologists and aid workers less likely to seek out the source of what was in fact a particular infection not only new to Haiti, but the entire hemisphere."
"And it has since continued to provide cover for the United Nations as advocates press for reparations, and public health experts try to reform the peacekeeping system to prevent such a catastrophic error from happening again." he added.
"Conditioned to look for a problem that wasn’t there, responders ignored the greatest public health threat of all: themselves."
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Woodrow Wilson, as described in the introductory section of the text, was the leader of the immediate post-war period and was the architect of an internationalist vision for a new world order. Yet, as discussed in the paragraphs below, he was not able to persuade the other Allied leaders at the peace settlement negotiations in Paris to embrace his vision. But it was not just the opposition of Clemenceau and Lloyd George to some of his ideas that moved the conference away from Wilson's vision. Wilson became so blindingly caught up in his vision, thinking that everything he advocated was what democracy and justice wanted, that he completely alienated the other negotiators in Paris, and they stopped listening to him. Another historian points to a different problem, that Wilson himself stopped listening to his earlier vision, having become convinced that a harsh peace was justified and desirable. Even if that historical view is accurate, Wilson was probably still more moderate in his conception of a harsh peace than were Clemenceau and Lloyd George. But as the conference dragged on and the departure from Wilsonianism became more and more pronounced, Wilson clung to his proposal for the League of Nations. In fact, he seemed to place all his faith in his pet project, believing it would solve all the evils the negotiators were unable to solve during the conference. Unfortunately, Wilson made it clear that the League was his primary objective, and it came to be his only bargaining chip. He then compromised on numerous issues that had no corollary in his vision in order to maintain the support for the creation of the League. Thus, though full of good intentions and a vision for a just and peaceful future, Wilson's arrogance and ineffective negotiating skills largely contibuted to the downfall of his vision. Finally, it must be mentioned that Wilson's inability to negotiate with the Senate in its discussion of the ratification of the Treaty of Versailles caused the Senate to reject the Treaty, leaving the United States noticeably absent from the newly created League of Nations, which greatly undermined the effectiveness and importance of Wilson's principal goal. Nonetheless, Wilson was awarded the 1919 Nobel Peace Prize for his efforts to secure a lasting peace and the success in the creation of the League of Nations.
David Lloyd George, the British Prime Minister,
entered the negotiations in Paris with the clear support of the British
people, as evidenced by his convincing win in the so-called khaki election
of December 1918.
During the weeks leading up to the election, though, he had publicly committed
himself to work for a harsh peace against Germany, including obtaining
payments for war damages committed against the British. These campaign
promises went against Lloyd George's personal convictions. Knowing
that Germany had been Britain's best pre-war trading partner, he thought
that Britain's best chance to return to its former prosperity was to restore
Germany to a financially stable situation, which would have required a
fairly generous peace with respect to the vanquished enemy.
Nonetheless, his campaign statements showed Lloyd George's understanding
that the public did not hold the same convictions as he did, and that,
on the contrary, the public wanted to extract as much as possible out of
the Germans to compensate them for their losses during the war. So
Lloyd George and Clemenceau were in agreement on many points, each one
seeming to support the other in their nationalist objectives, and thereby
scratching each other's back as the "game of grab" of Germany's power played
itself out. But most historians do not attribute to Lloyd George
a significant role in the Treaty negotiations.
In their defense, Clemenceau and Lloyd George were only following popular sentiment back home when they fought for harsh terms against Germany. It is clear from historical accounts of the time that after seeing so many young men not return from the trenches on the Western front, the French and British wanted to exact revenge against the Germans through the peace settlement, to ensure that their families would never again be destroyed by German aggression. In that respect, democracy was clearly functioning as it is intended in a representative democracy. In fact, Lloyd George is the quintessential example of an elected leader serving the interests of his people, putting his personal convictions second to British public opinion. Yet it was that same public opinion (in France and Britain) that Wilson had believed would support his internationalist agenda, placing Germany in the context of a new and more peaceful world order which would prevent future aggression. Wilson's miscalculation was one of the single greatest factors leading to the compromise of his principles and the resulting harsh and, in the eyes of many, unjust treatment of Germany within the Treaty of Versailles.
[See also the biographies of the Big Three listed
on the Links
1. James L. Stokesbury, A Short History of World War I, 1981, p. 309.
2. Manfred F. Boemeke, "Woodrow Wilson's Image of Germany, the War-Guilt Question, and the Treaty of Versailles,"inThe Treaty of Versailles: A Reassessment After 75 Years, Ch. 25, Boemeke, Feldman & Glaser, eds., 1998, pp. 603-614.
3. Robert H. Ferrell, Woodrow Wilson and World War I: 1917-1921, 1985, p. 146.
4. Lawrence E. Gelfand, "The American Mission to Negotiate Peace: An Historian Looks Back," in The Treaty of Versailles: A Reassessment After 75 Years, Ch. 8, Boemeke, Feldman & Glaser, eds., 1998, p. 191.
5. See Ferrell, supra note 3, Ch. 10, "The Senate and the Treaty."
6. Information from this paragraph is taken from Ferrell, supra note 3, at 142, 144, 151.
7. Id. at 151.
8. Stokesbury, supra note 1, at 311-312.
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Biological species emerge and disappear in the natural course of evolution. There have been times in the Earth’s past when mass extinctions have occurred, causing a large number of species to disappear in a short time. This is generally believed to have happened due to external pressures on ecosystems, or sudden shocks and catastrophic events. We are currently going through such a period due primarily to the impact humans have had on the environment, and on plant and animal habitats. Some scientists believe that 50% of existing species may become extinct in the next 100 years.
Credit: Wikimedia Commons
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Introduction / History
Jews represent the oldest monotheistic religion of modern times. Because of the uniqueness of their history and culture, all Jews have a strong sense of identity. Persecution of and discrimination against the Jews have been the historical reasons for their migrations and settlements around the world.
The Jews of Europe arrived on the continent at least 2,000 years ago during the early days of the Roman empire. Since then, they have been a significant influence in the history and culture of Europe. Much of what is considered "Jewish" today finds its roots among the European Jews.
One of the unique features among European Jews is the distinction between the Ashkenazic Jews and the Sephardic Jews. The word Ashkenaz is derived from a Biblical word for the larger Germanic region of Europe. Therefore, Ashkenazim Jews are those whose ancestry is linked to that area. This group traditionally speaks the Yiddish language, which is a German dialect that has Hebrew and Slavic elements. The word Sephard was the name used by Jews in medieval times for the Iberian peninsula. Sephardim Jews, then, are the descendants of the Jews who lived in Spain or Portugal prior to expulsion in 1492 by King Ferdinand and Queen Isabella. Sephardim also have a distinctive language called Ladino, or Judeo-Spanish. This is a dialect of Castilian Spanish with Hebrew and Turkish elements.
What are their lives like?
During the last few centuries, Eastern Europe had the largest Jewish population in the world. National attitudes toward the Jews were ambivalent, depending on the usefulness of the Jewish inhabitants to the nations' rulers. Anti-Semitism was prevalent and frequently led to either persecution or expulsion. The Holocaust of World War II was the climax of Jewish persecution in Europe, leading to the extermination of six million Jews. Many Eastern European countries lost the majority of their Jewish population in this tragedy.
As a result of the Holocaust, thousands of Jewish survivors and their descendants have emigrated from Eastern Europe to Israel, the United States, or Western Europe. The recent memories of the Holocaust as well as the centuries of discrimination and persecution play a strong part in modern Jewish identity. European Jews are strong supporters of "Zionism," a revival of Jewish culture and support of Israel as a national, secure, Jewish homeland.
Since the dissolution of the Soviet empire, former Soviet Jews no longer live under oppressive government rule. Anti-Semitism is still a concern, but Jewish life has been revitalized in recreated countries like the Ukraine. Synagogues are functioning and kosher (traditional, acceptable) food is once again available.
The Jewish emigration from Eastern Europe is cause for concern among the remaining aged Jewish population. As the older Jews die, the Jewish community dwindles. Many of the younger Jews are unlearned in their Jewish identity. They are either non-observant or have assimilated into the prevailing culture. However, strong efforts are being made to maintain a Jewish presence and clarify their identity. Jewish schools are being opened and Judaic studies are being promoted in universities. Jewish hospitals and retirement homes are being built. Community centers also promote cultural events such as the Israeli dance, theater, Yiddish and Hebrew lessons, and sports.
Western Europe now has the largest concentration of European Jewish residents. The Netherlands received a large influx of Sephardic Jews from Portugal in the late 1500's, and another contingent of Ashkenazic Jews after World War II. They have been very influential in the development of Dutch commerce. England's Jews are concentrated in the Greater London area and have been politically active for over 100 years. They have been avid supporters of Zionism and solidly committed to the settlement of Diaspora Jews in Israel. A large percentage of England's Jews are affiliated with the traditional Orthodox synagogues. Italy's Jewish population is primarily Sephardic due to its absorption of Spanish Jews in the 1500's. France's Ashkenazic community received 300,000 Sephardic Jews from North Africa in recent decades.
What are their beliefs?
For religious Jews, God is the Supreme Being, the Creator of the universe, and the ultimate Judge of human affairs. Beyond this, the religious beliefs of the Jewish communities vary greatly. European Jews are extremely diverse in religious practice. The Ashkenazic Jews are the most prevalent, representing the Orthodox, ultra-Orthodox, Conservative, and Reform movements. The unusual and adamantly traditional Hasidic movement was born in Poland and has gained a strong following in the United States and Israel. The Sephardic denomination is similar to the Orthodox Ashkenazic, but is more permissive on dietary rules and some religious practices. Each Jewish denomination maintains synagogues and celebrates the traditional Jewish holiday calendar. While most European Jews are religiously affiliated, there is a significant minority which is not religious.
What are their needs?
The Jews have a wonderful understanding of their connection with the Abrahamic covenant. However, they also have a history of rejecting Jesus Christ as Messiah, the one who has fulfilled that covenant. Pray that as the Gospel is shared, it will not be viewed as anti-Semitic, but rather as the fulfillment of what God promised through Abraham centuries ago.
Prayer PointsView Jew, Eastern Yiddish-Speaking in all countries.
* Ask the Lord of the harvest to send forth loving Christians to work among the Jewish communities.
* Ask the Holy Spirit to grant wisdom and favor to the missions agencies that are focusing on the European Jews.
* Pray that the Jewish people will understand that Jesus is the long-awaited Messiah.
* Ask the Lord to soften the hearts of the Jews towards Christians so that they might hear and receive the message of salvation.
* Pray that the Lord Jesus will reveal Himself to the Jews through dreams and visions.
* Pray that God will grant Jewish believers favor as they share their faith in Christ with their own people.
* Pray that strong local churches will be raised up in each Jewish community.
* Pray for the availability of the Jesus Film in the primary language of this people.
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The Oregon Trail opened the way west for intrepid settlers and enterprising miners. Once it was well established and the roads were cleared and expanded, once towns had grown up along the route and locations in the Rockies and further west were settled, it was only natural that a new method of transportation would take over: stagecoaches.
The technology behind stagecoaches wasn’t new. Carriages were the primary form of mass transportation in the pre-locomotive age. What made stagecoaches different from regular carriages were their size and the way they were supported on the wheel frame. Rather than relying on springs, which jostled a rider up and down, stagecoaches made use of thoroughbraces, leather straps that supported the body of the stagecoach and gave it more of a rocking motion.Stagecoaches could generally fit nine passengers inside and six outside. Inside, as you can probably guess, meant that passengers traveled inside the body of the coach. They would ride on three benches, two facing forward and the foremost one facing backwards, three riders to a bench. As you can imagine, it was a tight squeeze. Passengers in the first two benches would often have to wedge their knees between one another to make room. They would carry their baggage and often have mail under their feet. But if that wasn’t bad enough, the six passengers riding outside of the carriage would be just as cramped and exposed to the elements.
But what passengers lost in comfort, they made up for in speed. The most common type of stagecoach was the Concord stagecoach, manufactured in Concord, New Hampshire. These stagecoaches rarely broke down. They were drawn by a team of six horses and could cut through the new roadways of the west much faster than any wagon train ever could.
This is part of the reason that almost all stagecoaches carried mail as well as passengers. More than just mail, in fact. It was common for stagecoaches to carry gold and cash being transported on behalf of one bank or another. This, of course, meant that there was a real danger of robberies along the road.
The first major stagecoach robbery in California took place in 1852 when Reelfoot Williams and his gang robbed a Nevada City coach. The gang had set up a network of informants to monitor when stages were coming and what money and passengers they were carrying. They carried off the heist, setting a precedent that many would follow. For that reason, and because of the very real threat of attacks by Native Americans, passengers were advised to carry guns and knives with them and drivers were well armed.
So, you might ask yourself. Who was in charge of all these stagecoaches? You probably already know the answer without knowing it. There were several stagecoach companies in the east that had been in operation even before the 19th century. But one of the biggest and most successful companies developed in the 1830s as a service to deliver packages between Boston, New York, and Philadelphia. Adams & Company gradually moved west as steamships replaced overland routes for fast transportation between the major eastern cities.
Adams & Company did well in California after the gold rush, until mismanagement and the emergence of a serious competitor changed everything. That competitor was a little company started by two men, Henry Wells and William G. Fargo. The company that Wells and Fargo started offered more than just stagecoach service. It offered banking and mail services as well. In fact, by the time the 1850s rolled around, Wells Fargo was widely known to be faster and more reliable about delivering the mail than the U.S. Postal service.
Then came the Panic of 1855. The California banking system, puffed up on speculation of continued profits from the Gold Rush, collapsed. Many businesses, including Adams & Company, folded. But Wells Fargo managed to hold on. Not only did it hold on, it emerged as one of the only viable options in stagecoach transportation.
Since Wells Fargo pretty much had a monopoly on stagecoach transportation in the west after 1855, they could make the rules. And some of those rules were:
Abstinence from liquor is requested, but if you must drink share the bottle. To do otherwise makes you appear selfish and unneighborly.
If ladies are present, gentlemen are urged to forego smoking cigars and pipes as the odor of same is repugnant to the gentler sex. Chewing tobacco is permitted, but spit with the wind, not against it.
Gentlemen must refrain from the use of rough language in the presence of ladies and children.
Buffalo robes are provided for your comfort in cold weather. Hogging robes will not be tolerated and the offender will be made to ride with the driver.
Don’t snore loudly while sleeping or use your fellow passenger’s shoulder for a pillow; he or she may not understand and friction may result.
Firearms may be kept on your person for use in emergencies. Do not fire them for pleasure or shoot at wild animals as the sound riles the horses.
In the event of runaway horses remain calm. Leaping from the coach in panic will leave you injured, at the mercy of the elements, hostile Indians and hungry coyotes.
Forbidden topics of conversation are: stagecoach robberies and Indian uprisings.
Gents guilty of unchivalrous behavior toward lady passengers will be put off the stage. It’s a long walk back. A word to the wise is sufficient.*
So there you have it. Stagecoach transportation in the Old West. Traveling by stagecoach was the only way to go in those days … until the railroad came along and changed everything….
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After the British Pyrrhic (costly) victory at Bunker Hill in 1775, British General William Howe decided a lethal blow needed to be delivered to the Patriot cause. Howe proposed to launch an attack on New York City using tens thousands of troops. He began mobilizing the massive fleet in Halifax, Nova Scotia. Meanwhile, American Commander-in-Chief George Washington had ordered General Charles Lee to prepare for the defense of the city. That June, Howe and 9,000 troops set sail for New York. Howe’s army was to be met in the city by additional regiments of German and British troops. Reinforcements from Halifax led by Howe’s brother would follow them.
Howe’s initial fleet arrived in New York Harbor and began landing troops on Staten Island. On April 27, 1776, British forces engaged the Americans at the Battle of Brooklyn Heights (also called the Battle of Long Island). Howe’s army successfully outflanked Washington’s, eventually causing the Patriots, after some resistance, to withdraw to Manhattan under the cover of darkness, thereby avoiding a potentially costly siege at the hands of the British.
After failed peace negotiations, the British Army next struck at Lower Manhattan, where 12,000 British troops quickly overtook the city. Most of the Continental Army had retreated to defensible positions at Harlem Heights and then to White Plains, well north of the city, but some soldiers remained at Fort Washington in Manhattan. Howe’s army chased Washington and the Continental Army into positions north of White Plains before returning to Manhattan. In Manhattan, Howe set his sights on Fort Washington, the last Patriot stronghold in Manhattan. In the furious, three-pronged attacked, British forces easily took the fort, capturing nearly 3,000 American prisoners and at least 34 cannons in the process. Most of the prisoners were taken to squalid British prison ships where all but 800 or so died of disease or starvation. General Washington, now at Fort Lee, directly across the Hudson River from Fort Washington, witnessed the events that happened. Following the fall of Fort Washington, British forces ferried up the Hudson River in barges toward Fort Lee. Washington ordered the evacuation of the fort’s 2,000 soldiers across the Hackensack River at New Bridge Landing. Washington would lead his army clear across the Delaware River into Pennsylvania.
Following the events in and around New York City, the outlook was bleak for the Continental Army. Morale in the army was extremely low, enlistments were ending, and desertions were commonplace. Even General Washington admitted his army’s chances of success were slim. Meanwhile, General Howe ordered his army into their winter quarters that December and established several outposts from New York City south to New Brunswick, New Jersey.
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The Solar and Heliospheric Observatory (SOHO) spacecraft is expected to discover its 1,000TH comet this summer.
The SOHO spacecraft is a joint effort between NASA and the European Space Agency. It has accounted for approximately one-half of all comet discoveries with computed orbits in the history of astronomy.
"Before SOHO was launched, only 16 sun grazing comets had been discovered by space observatories. Based on that experience, who could have predicted SOHO would discover more than 60 times that number, and in only nine years," said Dr. Chris St. Cyr. He is senior project scientist for NASA's Living With a Star program at the agency's Goddard Space Flight Center, Greenbelt, Md. "This is truly a remarkable achievement!"
About 85 percent of the comets SOHO discovered belongs to the Kreutz group of sun grazing comets, so named because their orbits take them very close to Earth's star. The Kreutz sun grazers pass within 500,000 miles of the star's visible surface. Mercury, the planet closest to the sun, is about 36 million miles from the solar surface.
SOHO has also been used to discover three other well-populated comet groups: the Meyer, with at least 55 members; Marsden, with at least 21 members; and the Kracht, with 24 members. These groups are named after the astronomers who suggested the comets are related, because they have similar orbits.
Many comet discoveries were made by amateurs using SOHO images on the Internet. SOHO comet hunters come from all over the world. The United States, United Kingdom, China, Japan, Taiwan, Russia, Ukraine, France, Germany, and Lithuania are among the many countries whose citizens have used SOHO to chase comets.
Almost all of SOHO's comets are discovered using images from its Large Angle and Spectrometric Coronagraph (LASCO) instrument. LASCO is used to observe the faint, multimillion-degree outer atmosphere of the sun, called the corona. A disk in the instrument is used to make an artificial eclipse, blocking direct light from the sun, so the much fainter corona can be seen. Sun grazing comets are discovered when they enter LASCO's field of view as they pass close by the star.
"Building coronagraphs like LASCO is still more art than science, because the light we are trying to detect is very faint," said Dr. Joe Gurman, U.S. project scientist for SOHO at Goddard. "Any imperfections in the optics or dust in the instrument will scatter the light, making the images too noisy to be useful. Discovering almost 1,000 comets since SOHO's launch on December 2, 1995 is a testament to the skill of the LASCO team."
SOHO successfully completed its primary mission in April 1998. It has enough fuel to remain on station to keep hunting comets for decades if the LASCO continues to function.
For information about SOHO on the Internet, visit:
Explore further: Long-term warming, short-term variability: Why climate change is still an issue
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Teaching Strategies: Effective Discussion Leading
While lecturing is a fast and direct way to communicate a body of knowledge, discussion encourages students to discover solutions for themselves and to develop their critical thinking abilities. They learn how to generate ideas, consider relevant issues, evaluate solutions, and consider the implications of these solutions. Thus, although discussion is not as efficient as lecture in conveying facts, it helps students learn how to think better and more clearly about the facts that they should learn from their reading and their lectures.
Leading a discussion, however, offers its own set of challenges: participants can spend too much time exploring small, sometimes irrelevant issues, forget that they are progressing toward an identifiable goal, and become bored. The leader must guide the conversation carefully without stifling creativity and students' initiative and without surrendering to some students' desire for answers that they can write down and memorize.
Here are four strategies that can help faculty and TAs encourage students explore issues themselves:
We all know that creating a fine lecture requires research and planning; we sometimes forget that leading a good discussion requires the same research and planning and demands spontaneous responses in the classroom. The beauty of the extra demand is that developing the skills for intervening and directing discussions leads to exciting, productive exchanges that help students learn to think clearly and creatively, while simultaneously inspiring you to teach more thoroughly and carefully.
"Discussions: Leading and Guiding, but Not Controlling," The
Teaching Professor VI, 8 [October 1992].)
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For many, 1066 is the date when the Middle Ages began. Centuries of castles, cathedrals and churches followed, busy with chivalry, the Crusades and crop-rotation, all ending some time around 1500.
This, of course, is an over-simplification, just as the term Middle Ages itself is. For a long time, the civilisations of the Romans and the Renaissance were admired; everything in between – the ages in the middle - was regarded as inferior, a period of decline, disease and instability. Only with the Victorians was there some attempt to reconsider these centuries. They, like us, were transfixed by the imaginative leaps of medieval buildings and their intense spirituality.
Certain themes dominate medieval architecture. First, the church was central to everyday life. Usually the most impressive building in the neighbourhood was the parish church, and the finest buildings created were the great stone cathedrals. Secondly, society was strictly ordered. For most of the Middle Ages, the hierarchy of the Feudal System dominated: the majority were poor peasants living in simple dwellings that have long disappeared. A few, the lords and clergy, were rich. Their castles, manor houses, monasteries and colleges by comparison were splendid constructions, and have survived in some form. Thirdly, although technology was limited, building methods and styles did evolve. Throughout the Gothic style dominated, but in a myriad of forms.
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Presenting - 'Amasia', The Next Supercontinent!
Ever since Earth has been in existence there have been the formation and breaking apart of many supercontinents - While Pangaea, that existed between 150-300 million years ago is the most well-known, prior to that was Nuna (1.8 billion years ago), Rodina (1 billion years ago) and many more that cannot be verified because 2 billion year-old rocks containing evidence of magnetic fields, are hard to find.
And while most scientists are in agreement that Rodina, Nuna and Pangaea did exist, there is very little consensus on the continents they comprised of - Some experts believe that they were the same ones, while others think that the wandering landmasses reassembled on the opposite sides each time - about 180° away from where the previous supercontinent had come together.
Now, a group of geologists led by Yale University graduate student Ross Mitchell have a new theory - They think that each supercontinent came together about 90° from its predecessor. That is, the geographic center of Rodina was about 88° away from the center of Nuna, whilst the center of Panagea, believed to have been located near modern-day Africa, was about 88° away from the center from its super giant predecessor, Rodina.
These calculations that were reported earlier this year were based not only on the paleolatitude (The latitude of a place at some time in the past, measured relative to the earth's magnetic poles in the same period) of the ancient supercontinents, but also, for the first time the paleolongitude, that Ross measured by estimating how the locations of the Earth's magnetic poles have changed through time.
While the theory is interesting, what is even more so is that the team has also come up with a model of the next supercontinent. If their estimates are accurate, over the next few hundred million years, the tectonic plates under the Americas and Asia will both drift northward and merge. This means that modern day North and South America will come together and become one giant landmass, displacing the Caribbean Sea completely. A similar movement in Eurasia (Australia and South Eastern Asia) will cause the Arctic Ocean to disappear causing the continents to fuse with Canada. The result? A ginormous continent that they call 'Amasia'. The one thing that is not too clear is if Antarctica will be part of this or just be left stranded.
While many researchers believe that the Yale team's theory is quite feasible, nobody will ever know for sure - Because unfortunately, none of us are going to be around few 100 million years from now - But it's sure fun to envision the new world, isn't it?
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Researchers at New Jersey Institute of Technology (NJIT) have developed an inexpensive solar cell that can be painted or printed on flexible plastic sheets.
“Someday, homeowners will even be able to print sheets of these solar cells with inexpensive home-based inkjet printers. Consumers can then slap the finished product on a wall, roof or billboard to create their own power stations,” said Somenath Mitra, Ph.D., lead researcher, professor and acting chair of NJIT’s Department of Chemistry and Environmental Sciences.
Harvesting energy directly from abundant solar radiation using solar cells is increasingly emerging as a major component of future global energy strategy, Mitra said. Yet, when it comes to harnessing renewable energy, challenges remain.
Expensive, large-scale infrastructures, such as windmills or dams, are necessary to drive renewable energy sources, such as wind or hydroelectric power plants. Purified silicon, also used for making computer chips, which continue to rise in demand, is a core material for fabricating conventional solar cells. However, the processing of a material such as purified silicon is beyond the reach of most consumers.
“Developing organic solar cells from polymers, however, is a cheap and potentially simpler alternative,” Mitra said. “We foresee a great deal of interest in our work because solar cells can be inexpensively printed or simply painted on exterior building walls and/or rooftops. Imagine some day driving in your hybrid car with a solar panel painted on the roof, which is producing electricity to drive the engine. The opportunities are endless.”
The solar cell developed at NJIT uses a carbon nanotubes complex, which is a molecular configuration of carbon in a cylindrical shape. Although estimated to be 50,000 times smaller than a human hair, just one nanotube can conduct current better than any conventional electrical wire.
Mitra and his research team took the carbon nanotubes and combined them with tiny carbon fullerenes (sometimes known as buckyballs) to form snake-like structures. Buckyballs trap electrons, although they can’t make electrons flow. Add sunlight to excite the polymers, and the buckyballs will grab the electrons. Nanotubes, behaving like copper wires, then will be able to make the electrons or current flow.
“Someday, I hope to see this process become an inexpensive energy alternative for households around the world,” Mitra said. EC
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|This is a measure of the brightness of a celestial object. The lower the value, the brighter the object, so magnitude -4 is brighter than magnitude 0, which is in turn brighter than magnitude +4. The scale is logarithmic, and a difference of 5 magnitudes means a brightness difference of exactly 100 times. A difference of one magnitude corresponds to a brightness difference of around 2.51 (the fifth root of 100).
The system was started by the ancient Greeks, who divided the stars into one of six magnitude groups with stars of the first magnitude being the first ones to be visible after sunset. In modern times, the scale has been extended in both directions and more strictly defined.
Examples of magnitude values for well-known objects are;
|Sun||-26.7 (about 400 000 times brighter than full Moon!)|
|Brightest Iridium flares||-8|
|Venus (at brightest)||-4.4|
|International Space Station||-2|
|Sirius (brightest star)||-1.44|
|Limit of human eye||+6 to +7|
|Limit of 10x50 binoculars||+9|
|Limit of Hubble Space Telescope||+30|
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One of the basic tenets of teaching is that the student must learn the basics and foundation of a subject in order for them to master it eventually and reach full human potential.
New research from the University of Missouri supports this notion, revealing that kids who understood numbers and quantity in the first grade were more likely to get good grades in math when they hit fifth grade.
“This study reinforces the idea that math knowledge is incremental, and without a good foundation, a student won’t do well because the math gets more complex,” said researcher David Geary. “The kids that can go back and forth easily and quickly in translating numerals, the number five, for example, into quantities and in breaking complex problems into smaller parts had a very good head start.”
The study involved 177 elementary school students from kindergarten. Researchers hope to follow the group until they reach 10th grade algebra classes in an attempt to gain a deeper understanding of how kids learn, especially when it comes to math. Additionally, the findings may help educators discover better methods of teaching.
Personal growth activities such as studying, doing homework and attending school are integral to a young person's development and can even set them on the right path toward a fulfilled life.
Philosopher, educator and trailblazer Ilchi Lee believes that human potential is limitless and that individuals can push the boundaries of their abilities with practice and hard work. Results of this study support such thoughts, providing further proof that the brain works gradually.
Students may want to consider ridding their minds of distractions and negativity before engaging in study sessions or attending class in order to reap the full benefits of education.
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Leaf Characteristics (PK1) This set introduces simple vocabulary to describe the physical features of 40 North American tree, garden, and house plant leaves. First - The child sorts 9 leaf characteristics cards (3" x 4") onto 3 control cards (10-3/8” x 5¼”) that identify characteristics of Leaf Types, Leaf Veins, and Leaf Margins. Second - After learning the 9 characteristics of leaves, it is time to describe the 3 characteristics of just one leaf. A leaf card is selected from the 40 leaf cards provided (3" x 4"). The child selects the 3 characteristics cards (type, venation, margin) that describe that leaf, and places them on the blank Leaf Identification card (10-3/8” x 5¼”). Real leaves can be used in this exercise as well. Background information is included for the teacher.
Leaves (PK1C) This set consists of 40 DUPLICATE leaf cards (80 cards total). One group of 20 cards illustrates familiar leaves such as dandelion, marigold, and ivy. The second group illustrates common North American tree leaves such as oak, maple, and cottonwood. These are the same leaf cards found in In-Print for Children's “Leaf Characteristics” activity.
Flowers (FL1) This set is designed to help children recognize and to name 20 common flowers, many of which are commercially available throughout the year. This duplicate set of picture cards can be used in simple matching exercises, or in 3-part matching activities if one set is cut apart. The 40 photocards (3¼” x 4") are in full-color and laminated. Flower background information is included for the teacher.
Nuts (PK3) Nuts are nourishing snacks and learning how they grow will make eating them all the more fun! This set of 22 two-color cards (5½” x 3½”) of plant and nut illustrations represents eleven edible nuts/seeds. The child pairs the illustration cards of the nuts in their growing stage to the cards of the nuts in and out of their shells. Make the activity even more successful by bringing the real nuts into the classroom.
Kitchen Herbs & Spices (PK5) This set help children to learn about 20 plants that give us herbs and spices. The delicately drawn, 2-color illustrations clearly show the parts of the plants that give us edible leaves, seeds, stems, bark, bulbs, and berries. Create an aromatic and tasty exercise by having the children pair real herbs and spices with these cards (4½” x 6¼”).
Plants We Eat (PK9) Learn more about food plants and their different edible parts. This set classifies 18 plant foods into six groups: roots, stems, leaves, flowers, fruits, and seeds. A duplicate set of 18 labeled picture/definition cards (6" x 6") shows plants in their growing stage with only their “food” portion in color. One set of picture/ definition cards is spiral bound into 6 control booklets that include definitions of the root, stem, leaf, flower, fruit, and seed. The other set of picture/ definition cards are to be cut apart for 2 or 3-part matching exercises. Plant description cards can be used for “Who am I?” games with our plant picture cards or with real foods. Both cards and booklets are laminated.
Plants We Eat Replicards (PK9w) Six replicards are photocopied to produce worksheets for an extension exercise using our set Plants We Eat (PK9). Children color and label the worksheets, which illustrate three plant examples for each of the following groups: roots, stems, leaves, flowers, fruits, and seeds. The Plants We Eat booklets serve as controls. After worksheets (8½” x 11") are colored and labeled, they can be cut apart, stapled together, and made into six take-home booklets. These booklets may generate lively family dinner-table discussions: “A potato is a what?”
Plants - Who am I? (WP) This beginning activity for lower elementary strengthens both reading and listening skills, and provides children with simple facts about 10 plants. The set consists of duplicate, labeled picture cards with descriptive text and features plants different from those in the First Knowledge: Plant Stories (see below). The set of cards with text ending in “Who am I?” is cut apart into 10 picture cards, 10 plant name cards, and 10 text cards. The other set is left whole. Cards are used for picture-to-text card matching exercises and for playing the “Who am I” game. Cards measure 6½” x 4" and are in full color and laminated.
First Knowledge: Plant Stories (PK7) This set consists of 19 duplicate plant picture/text cards. One set is cut apart for 3-part matching activities, and the other set is placed in the green, 6-ring mini-binder labeled Plants. The teacher has the option of changing the cards in the binder as needed. The children can match the 3-part cards (6" x 3¾”) to the cards in the binder, practice reading, learn about the diverse characteristics of these plants, and then play “Who am I?” The eight angiosperms picture cards can be sorted beneath two cards that name and define Monocots and Dicots. These activities prepare children for later work with our Plant Kingdom Chart & Cards (see below), which illustrates the same plants.
Plant Kingdom Chart and Cards (PK6) Our 4-color plastic paper chart and cards represents the current classification of the plant kingdom (not illustrated here) – the same as is used in secondary and college level biology courses. This classification organizes the plant kingdom in a straightforward manner with simple definitions and examples under each heading. Firs the plants are categorized as either Nonvascular Plants (Bryophytes) or Vascular Plants. Then the Vascular plants are divided into two groups: Seedless Plants or Seed Plants. Seed Plants are divided into two groups: Gymnosperms and Angiosperms with sub-categories. Nineteen picture cards (2¼” x 3") illustrate the currently recognized phyla of the plant kingdom. Children match the 19 plant picture cards to the pictures on the chart (18" x 32"). Text on the back of the picture cards describes each plant. Advanced students can recreate the chart with the title cards provided, using the chart as a control of error. Background information is provided.
Parts of a Mushroom Parts of a gilled mushroom are highlighted and labeled on six 2-color cards (3" x 5"). Photocopy the Replicard (8½” x 11") to make quarter page worksheets. The child colors and labels the worksheets, using the picture cards as a guide. Completed worksheets can be stapled together to make a booklet for “Parts of a Mushroom”. (In-Print product code FK1)
Fungi (FK4) Members of the Fungus Kingdom have a wide variety of forms. Children see fungi everywhere, such as mold on food, or mushrooms on the lawn. This duplicate set of labeled picture cards shows 12 common fungi found indoors and out. Fungi illustrated: blue cheese fungus, bolete, coral fungus, cup fungus, jelly fungus, lichens, mildew, milky mushrooms, mold, and morel. Background information is included. Pictures cards (3½” x 4½”) are in full color and laminated.
Classification of the Fungus KingdomChart and Cards (FK3) This classification of the Fungus Kingdom organizes 18 representative fungi into four major groups and two important fungal partnerships: Chytrids, Yoke Fungi, Sac Fungi, Club Fungi, Lichens, Mycorrhizae. Children match the 18 picture cards (2-7/8” x 2-3/8”) to the pictures on the 2-color chart (18" x 16"). After this activity, they can sort the picture cards under the label cards for the 5 fungus groups, using the chart as the control. Description of each fungus type is printed on the back of the picture cards. Background information is included for the teacher. This chart is printed on vinyl and does not need to be laminated.
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Scientists gets further evidence that Mars once had oceans
Mars, our neighbor, once the dreams of science fiction writers and astronomers, one of which only wrote about the live that could have lived on Mars, and still might; while the other seeks to prove that there might actually have been life on that red planet eons ago.
Part of proving that idea is being able to show that there was water on the surface of Mars, water that would have been the foundation of life, just as it is here on earth.
To help find the facts behind whether there was, or even still is, water on Mars the European Space Agency (ESA) Mars Express space craft which houses the Mars Advanced Radar for Subsurface and Ionsphere Sounding (MARSIS) has detected sediment on the planet, the type of sediment that you would find on the floor of an ocean.
It is within the boundaries of features tentatively identified in images from various spacecraft as shorelines that MARSIS detected sedimentary deposits reminiscent of an ocean floor.
“MARSIS penetrates deep into the ground, revealing the first 60 – 80 meters (197 – 262 ft) of the planet’s subsurface,” says Wlodek Kofman, leader of the radar team at the Institut de Planétologie et d’Astrophysique de Grenoble (IPAG). “Throughout all of this depth, we see the evidence for sedimentary material and ice.”
The sediments detected by MARSIS are areas of low radar reflectivity, which typically indicates low-density granular materials that have been eroded away by water and carried to their final resting place.
Scientists are interpreting these sedimentary deposits, which may still be ice-rich, as another indication that there once an ocean in this spot.
At this point scientists have proposed that there were two main oceans on the planet. One was aroun the 4 billion year ago range with the second at around 3 billion years ago.
For the scientist the MARSIS findings provide some of the best evidence yet that Mars did have large bodies of water on its surface and that the water played a major role in the planet’s geological history.
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The Current Surface Analysis map shows current weather conditions
, including frontal and high/low pressure positions, satellite infrared
(IR) cloud cover
, and areas of precipitation
. A surface weather analysis is a special type of weather map that provides a view of weather elements over a geographical area at a specified time based on information from ground-based weather stations. Weather maps are created by plotting or tracing the values of relevant quantities such as sea level pressure, temperature
, and cloud cover
onto a geographical map to help find synoptic scale features such as weather fronts.
The first weather maps in the 19th century were drawn well after the fact to help devise a theory on storm systems. After the advent of the telegraph, simultaneous surface weather observations
became possible for the first time, and beginning in the late 1840s, the Smithsonian Institution became the first organization to draw real-time surface analyses. Use of surface analyses began first in the United States, spreading worldwide during the 1870s. Use of the Norwegian cyclone model for frontal analysis began in the late 1910s across Europe, with its use finally spreading to the United States during World War II.
Surface weather analyses have special symbols which show frontal systems, cloud cover
, or other important information. For example, an H may represent high pressure, implying good and fair weather. An L on the other hand may represent low pressure, which frequently accompanies precipitation
. Various symbols are used not just for frontal zones and other surface boundaries on weather maps, but also to depict the present weather at various locations on the weather map. Areas of precipitation
help determine the frontal type and location.
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The knowledge, skills and understandings relating to students’ writing have been drawn from the Statements of Learning for English (MCEECDYA 2005).
Students are taught to write a variety of forms of writing at school. The three main forms of writing (also called genres or text types) that are taught are narrative writing, informative writing and persuasive writing. In the Writing tests, students are provided with a ‘writing stimulus' (sometimes called a prompt – an idea or topic) and asked to write a response in a particular genre or text type.
In 2013, students will be required to complete a persuasive writing task.
The Writing task targets the full range of student capabilities expected of students from Years 3 to 9. The same stimulus is used for students in Years 3, 5, 7 and 9. The lines in the response booklet for Year 3 students are more widely spaced than for Years 5, 7 and 9 and more capable students will address the topic at a higher level. The same marking guide is used to assess all students' writing, allowing for a national comparison of student writing capabilities across these year levels.
Assessing the Writing task
Students’ writing will be marked by assessors who have received intensive training in the application of a set of ten writing criteria summarised below. The full Persuasive Writing Marking Guide ( 5.7 MB) and the writing stimulus used to prompt the writing samples in the Marking Guide are both available for download.
Descriptions of the Writing criteria
||Description of marking criterion
|The writer’s capacity to orient, engage and persuade the reader
||The organisation of the structural components of a persuasive text (introduction, body and conclusion) into an appropriate and effective text structure
||The selection, relevance and elaboration of ideas for a persuasive argument
||The use of a range of persuasive devices to enhance the writer’s position and persuade the reader
||The range and precision of contextually appropriate language choices
||The control of multiple threads and relationships across the text, achieved through the use of grammatical elements (referring words, text connectives, conjunctions) and lexical elements (substitutions, repetitions, word associations)
||The segmenting of text into paragraphs that assists the reader to follow the line of argument
||The production of grammatically correct, structurally sound and meaningful sentences
||The use of correct and appropriate punctuation to aid the reading of the text
||The accuracy of spelling and the difficulty of the words used
The Narrative Writing Marking Guide (used in 2008 - 2010 ) is also available.
Use of formulaic structures
Beginning writers can benefit from being taught how to use structured scaffolds. One such scaffold that is commonly used is the five paragraph argument essay. However, when students becomes more competent, the use of this structure can be limiting. As writers develop their capabilities they should be encouraged to move away from formulaic structures and to use a variety of different persuasive text types, styles and language features, as appropriate to different topics.
Students are required to write their opinion and to draw on personal knowledge and experience when responding to test topics. Students are not expected to have detailed knowledge about the topic. Students should feel free to use any knowledge that they have on the topic, but should not feel the need to manufacture evidence to support their argument. In fact, students who do so may undermine the credibility of their argument by making statements that are implausible.
Example topics and different styles:
City or country (see example prompt )
A beginning writer could write their opinion about living in either the city or country and give reasons for it. A more capable writer might also choose to take one side and argue for it. However, this topic also lends itself to a comparative style response from a more capable writer. It can be argued there are benefits and limitations to living in the city and living in the country. A writer could also choose to introduce other options, for example living in a large country town that might have the benefits of city and rural life. Positions taken on this topic are likely to elicit logical, practical reasons and anecdotes based on writers’ experiences.
Books or TV (see example prompt )
A beginning writer could write about their opinion of one aspect and give reasons for it. However, this topic lends itself to a comparative style response from a more capable writer. It can be argued there are benefits and limitations to both books and TV. The reasons for either side of the topic are likely to elicit logical, practical reasons and personal anecdotes based on the writer's experiences of both books and TV.
It is cruel to keep animals in cages and zoos (see example prompt )
A beginning writer could take on one side of the topic and give reasons for it. However, this topic lends itself to be further redefined. For example, a more capable writer might develop the difference between open range zoos and small cages and then argue the merits of one and limitations of the other. The animal welfare issues raised by this topic are likely to elicit very empathetic and emotive arguments based on the writer's knowledge about zoos and animals.
More information on persuasive writing can be found in the FAQ section for NAPLAN - Writing test.
National minimum standards
The national minimum standards for writing describe some of the skills and understandings students can generally demonstrate at their particular year schooling. The standards are intended to be a snapshot of typical achievement and do not describe the full range of what students are taught or what they may achieve.
For further information on the national minimum standards see Performance Standards.
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LESSON ONE: Transforming Everyday Objects
Marcel Duchamp: Bicycle Wheel, bicycle wheel on wooden stool, 1963 (Henley-on-Thames, Richard Hamilton Collection); © 2007 Artists Rights Society (ARS), New York/ADAGP, Paris, photo credit: Cameraphoto/Art Resource, NY
Man Ray: Rayograph, gelatin silver print, 29.4×23.2 cm, 1923 (New York, Museum of Modern Art); © 2007 Man Ray Trust/Artists Rights Society (ARS), New York/ADAGP, Paris, photo © The Museum of Modern Art, New York
Meret Oppenheim: Object (Le Déjeuner en fourrure), fur-lined cup, diam. 109 mm, saucer, diam. 237 mm, spoon, l. 202 mm, overall, h. 73 mm, 1936 (New York, Museum of Modern Art); © 2007 Artists Rights Society (ARS), New York/ProLitteris, Zurich, photo © Museum of Modern Art/Licensed by SCALA/Art Resource, NY
Dada and Surrealist artists questioned long-held assumptions about what a work of art should be about and how it should be made. Rather than creating every element of their artworks, they boldly selected everyday, manufactured objects and either modified and combined them with other items or simply se-lected them and called them “art.” In this lesson students will consider their own criteria for something to be called a work of art, and then explore three works of art that may challenge their definitions.
Students will consider their own definitions of art.
Students will consider how Dada and Surrealist artists challenged conventional ideas of art.
Students will be introduced to Readymades and photograms.
Ask your students to take a moment to think about what makes something a work of art. Does art have to be seen in a specific place? Where does one encounter art? What is art supposed to accomplish? Who is it for?
Ask your students to create an individual list of their criteria. Then, divide your students into small groups to discuss and debate the results and come up with a final list. Finally, ask each group to share with the class what they think is the most important criteria and what is the most contested criteria for something to be called a work of art. Write these on the chalkboard for the class to review and discuss.
Show your students the image of Bicycle Wheel. Ask your students if Marcel Duchamp’s sculp-ture fulfills any of their criteria for something to be called a work of art. Ask them to support their obser-vations with visual evidence.
Inform your students that Duchamp made this work by fastening a Bicycle Wheel to a kitchen stool. Ask your students to consider the fact that Duchamp rendered these two functional objects unus-able. Make certain that your students notice that there is no tire on the Bicycle Wheel.
To challenge accepted notions of art, Duchamp selected mass-produced, often functional objects from everyday life for his artworks, which he called Readymades. He did this to shift viewers’ engagement with a work of art from what he called the “retinal” (there to please the eye) to the “intellectual” (“in the service of the mind.”) [H. H. Arnason and Marla F. Prather, History of Modern Art: Painting, Sculpture, Architecture, Photography (Fourth Edition) (New York: Harry N. Abrams, Inc., 1998), 274.] By doing so, Duchamp subverted the traditional notion that beauty is a defining characteristic of art.
Inform your students that Bicycle Wheel is the third version of this work. The first, now lost, was made in 1913, almost forty years earlier. Because the materials Duchamp selected to be Readymades were mass-produced, he did not consider any Readymade to be “original.”
Ask your students to revisit their list of criteria for something to be called a work of art. Ask them to list criteria related specifically to the visual aspects of a work of art (such as “beauty” or realistic rendering).
Duchamp said of Bicycle Wheel, “In 1913 I had the happy idea to fasten a Bicycle Wheel to a kitchen stool and watch it turn.” [John Elderfield, ed., Studies in Modern Art 2: Essays on Assemblage (New York: The Museum of Modern Art, 1992), 135.] Bicycle Wheel is a kinetic sculpture that depends on motion for effect. Although Duchamp selected items for his Readymades without regard to their so-called beauty, he said, “To see that wheel turning was very soothing, very comforting . . . I en-joyed looking at it, just as I enjoy looking at the flames dancing in a fireplace.” [Francis M. Naumann, The Mary and William Sisler Collection (New York: The Museum of Modern Art, 1984), 160.] By en-couraging viewers to spin Bicycle Wheel, Duchamp challenged the common expectation that works of art should not to be touched.
Show your students Rayograph. Ask your students to name recognizable shapes in this work. Ask them to support their findings with visual evidence. How do they think this image was made?
Inform your students that Rayograph was made by Man Ray, an American artist who was well-known for his portrait and fashion photography. Man Ray transformed everyday objects into mysterious images by placing them on photographic paper, exposing them to light, and oftentimes repeating this process with additional objects and exposures. When photographic paper is developed in chemicals, the areas blocked from light by objects placed on the paper earlier on will remain light, and the areas exposed to light will turn black. Man Ray discovered the technique of making photograms by chance, when he placed some objects in his darkroom on light-sensitive paper and accidentally exposed them to light. He liked the resulting images and experimented with the process for years to come. He likened the technique, now known as the photogram, to “painting with light,” calling the images rayographs, after his assumed name.
Now that your students have identified some recognizable objects used to make Rayograph, ask them to consider which of those objects might have been translucent and which might have been opaque, based on the tone of the shapes in the photogram.
Now show your students Meret Oppenheim’s sculpture Object (Déjeuner en fourrure). Both Rayograph and Object were made using everyday objects and materials not traditionally used for making art, which, when combined, challenge ideas of reality in unexpected ways. Ask your students what those everyday objects are and how they have been transformed by the artists.
Ask your students to name some traditional uses for the individual materials (cup, spoon, saucer, fur) used to make Object. Ask your students what choices they think Oppenheim made to transform these materials and objects.
In 1936, the Swiss artist Oppenheim was at a café in Paris with her friends Pablo Picasso and Dora Maar. Oppenheim was wearing a bracelet she had made from fur-lined, polished metal tubing. Picasso joked that one could cover anything with fur, to which Oppenheim replied, “Even this cup and saucer.” [Bice Curiger, Meret Oppenheim: Defiance in the Face of Freedom (Zurich, Frankfurt, New York: PARKETT Publishers Inc., 1989), 39.] Her tea was getting cold, and she reportedly called out, “Waiter, a little more fur!” Soon after, when asked to participate in a Surrealist exhibition, she bought a cup, saucer, and spoon at a department store and lined them with the fur of a Chinese gazelle. [Josephine Withers, “The Famous Fur-Lined Teacup and the Anonymous Meret Oppenheim” (New York: Arts Magazine, Vol. 52, Novem-ber 1977), 88-93.]
Duchamp, Oppenheim, and Man Ray transformed everyday objects into Readymades, Surrealist objects, and photograms. Ask your students to review the images of the three artworks in this lesson and discuss the similarities and differences between these artists’ transformation of everyday objects.
Art and Controversy
At the time they were made, works of art like Duchamp’s Bicycle Wheel and Oppenheim’s Object were controversial. Critics called Duchamp’s Readymades immoral and vulgar—even plagiaristic. Overwhelmed by the publicity Object received, Oppenheim sunk into a twenty-year depres-sion that greatly inhibited her creative production.
Ask your students to conduct research on a work of art that has recently been met with controversy. Each student should find at least two articles that critique the work of art. Have your students write a one-page summary of the issues addressed in these articles. Students should consider how and why the work chal-lenged and upset critics. Was the controversial reception related to the representation, the medium, the scale, the cost, or the location of the work? After completing the assignment, ask your students to share their findings with the class. Keep a list of shared critiques among the work’s various receptions.
Make a Photogram
If your school has a darkroom, have your students make photograms. Each student should collect several small objects from school, home, and the outside to place on photographic paper. Their collection should include a range of translucent and opaque objects to allow different levels of light to shine through. Stu-dents may want to overlap objects or use their hands to cover parts of the light-sensitive paper. Once the objects are arranged on the paper in a darkroom, have your students expose the paper to light for several seconds (probably about five to ten seconds, depending on the level of light) then develop, fix, rinse, and dry the paper. Allow for a few sheets of photographic paper per student so that they can experiment with different arrangements and exposures. After the photograms are complete, have your students discuss the different results that they achieved. Students may also make negatives of their photograms by placing them on top of a fresh sheet of photographic paper and covering the two with a sheet of glass. After ex-posing this to light, they can develop the paper to get the negative of the original photogram.
Encourage your students to try FAUXtogram, an activity available on Red Studio, MoMA's Web site for teens.
GROVE ART ONLINE: Suggested Reading
Below is a list of selected articles which provide more information on the specific topics discussed in this lesson.
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OurDocuments.gov. Featuring 100 milestone documents of American history from the National Archives. Includes images of original primary source documents, lesson plans, teacher and student competitions, and educational resources.
In 1866 the Russian government offered to sell the territory of Alaska to the United States. Secretary of State William H. Seward, enthusiastic about the prospects of American Expansion, negotiated the deal for the Americans. Edouard de Stoeckl, Russian minister to the United States, negotiated for the Russians. On March 30, 1867, the two parties agreed that the United States would pay Russia $7.2 million for the territory of Alaska.
For less that 2 cents an acre, the United States acquired nearly 600,000 square miles. Opponents of the Alaska Purchase persisted in calling it “Seward’s Folly” or “Seward’s Icebox” until 1896, when the great Klondike Gold Strike convinced even the harshest critics that Alaska was a valuable addition to American territory.
The check for $7.2 million was made payable to the Russian Minister to the United States Edouard de Stoeckl, who negotiated the deal for the Russians. Also shown here is the Treaty of Cession, signed by Tzar Alexander II, which formally concluded the agreement for the purchase of Alaska from Russia.
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Filed under: Foundational Hand
After studying the proportions of the Foundational Hand letters, the next step is to start writing the letters.
Each letter is constructed rather than written. The letters are made up of a combination of pen strokes, which are only made in a top – down or left – right direction. The pen is never pushed up.
When we studied the proportions of the Foundational Hand we could group the letters according to their widths. Now, we can group them according to the order and direction of the pen strokes.
You may find it useful to look at the construction grid whilst studying the order and direction of the letters.
The first group consists of the letters c, e, and o.
These letters are based on the circle shape. This shape is produced with two pen strokes. Visualise a clock face and start the first stroke at approximately the 11, and finish it in an anti-clockwise direction at 5. The second stroke starts again at the 11 and finishes in a clockwise direction on the 5 to complete the letter o.
The first pen-stroke for the letters c and e are the same as the first of the letter o. The second pen-stroke on the c and e are shorter and finish around the 1 position on the imaginary clock face.
Finally, the letter e has a third stroke, starting at the end of the second stroke and finishes when it touches the first stroke.
The next group of letters are d, q, b and p. All these letters combine curved and straight pen strokes. When writing these letters it can be useful to think of the underlying circle shape, which your pen will leave or join at certain points depending upon which letter is being written.
The first stroke of the b starts at the ascender height of the letter, which can be eyed in at just under half the x-height (body height of letters with no ascender or descender). Continue the ascender stroke of the b until it ‘picks up’ the circle shape, follow round the circle until the pen reaches the 5 on the imaginary clock face. The second stroke starts on the first stroke following the circle round until it touches the end of the first stroke.
The letter d is similar to the c except it has a third stroke for the ascender, which will touch the ends of the first and second stroke being for finishing on the write-line.
Letter p starts with a vertical stroke from the x-height down to the imaginary descender line, which is just under half the x-height below the write-line. The second and third strokes are curved, starting on the descender stroke and following round the imaginary circle.
The letter q is almost the same as the d, except it has a descender stroke rather than an ascender stroke.
Letters a, h, m, n, r
All these letters combine curved and straight pen strokes. Once again, think of the underlying circle shape, which your pen will leave or join at certain points depending upon the letter being written.
The Letter h consists of two pen strokes. The first is a vertical ascender stroke. The second stroke starts curved, follows the circle round, then leaves it and becomes straight.
The letter n is produced exactly the same way as the letter h, except the first stroke is not so tall as it starts on the x-height line. The first two pen strokes of the letter m are the same as the letter n. Then a third stroke is added which is identical to the second stroke.
The letter r is also written the same way as the letter n except the second stroke finishes at the point where the circle would have been left and the straight is picked up.
The first stroke of letter a is the same as the second stroke of the letters h, m and n. The second stroke follows the circle. Finally, the third stroke starts at the same point as the second stroke, but is a straight line at a 30° angle and touches the first stroke.
The next group of letters are l, u and t. These letters are straight-forward. The letter l is the same as the first stroke of letter b.
The letter u is also similar to the first stroke of letter b except it starts lower down. The second stroke starts on the x-height line and finishes on the write-line.
Letter t has the same first stroke as letter u. It is completed by a second horizontal stroke.
The following letters k, v, w, x, y and z are made of at least one diagonal pen stroke.
The letter k starts with a vertical ascender stroke, then a second stroke diagonal stroke which joins the vertical stroke. The final stroke is also diagonal and starts where the first and second stroke meet and stops when it touches the write-line. If you look closely you will see it goes further out than the second stroke. This makes the letter look more balanced. If the end of these two pen-strokes lined up the letter would look like it is about to fall over.
Letter v is simply two diagonal strokes and these are repeated to produce the letter w.
The letter y is the same as the v except the second stroke is extended until to create a descender stroke.
Letter x is a little different, you need to create it in such a way that the two stroke cross slightly above the half-way mark on the x-height. This means the top part will be slightly smaller than the bottom which will give the letter a better balance.
Finally, in this group is letter z. The easiest way to produce this is with the two horizontal pen strokes, thenjoin these two strokes with a diagonal pen-stroke to complete the letter.
Now for the hardest letters; f, g and s. Out of these three letters, f is the simplest. It starts with a vertical ascender stroke – except this is not as tall as the other ascender strokes we have produced so far. This is because we have to allow for the second curved stroke. The overall height of these two strokes should be the same as other letters that have an ascender. Finally, we need a horizontal stroke to complete the letter.
Which will you find the hardest letter g or s? These are trickier because unlike all the other letters we have written they do not relate so well to the grid.
The letter g is made of a circle shape, with an oval/bowl shape under the write-line. You can see the letter g is made of three pen-strokes. The first stroke is just like the first stroke of the letter o for example, except it is a smaller. The second stroke starts like the second stroke of the letter o, but when it joins the first stroke it continues and changes direction in the gap between the bottom of the shape and the write-line. The third stroke completes the oval shape. Finally, we have a little fourth stroke to complete the letter.
The letter s is made up of three strokes. The first stroke is sort of an s shape! The second and third strokes complete the letter s. These are easier to get right than the first stroke because they basically follow the circle shape on our construction grid. The secret to this letter is to make both ‘ends’ of the first stroke not too curved. Because the other two strokes are curved they will compensate and give the overall correct shape.
Finally, we are left with the letters i and j, which are made from one pen-stroke. You just need to remember to curve the end of the stroke when writing the letter j.
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In January 1992, a container ship near the International Date Line, headed to Tacoma, Washington from Hong Kong, lost 12 containers during severe storm conditions. One of these containers held a shipment of 29,000 bathtub toys. Ten months later, the first of these plastic toys began to wash up onto the coast of Alaska. Driven by the wind and ocean currents, these toys continue to wash ashore during the next several years and some even drifted into the Atlantic Ocean.
The ultimate reason for the world's surface ocean currents is the sun. The heating of the earth by the sun has produced semi-permanent pressure centers near the surface. When wind blows over the ocean around these pressure centers, surface waves are generated by transferring some of the wind's energy, in the form of momentum, from the air to the water. This constant push on the surface of the ocean is the force that forms the surface currents.
Learning Lesson: How it is Currently Done
Around the world, there are some similarities in the currents. For example, along the west coasts of the continents, the currents flow toward the equator in both hemispheres. These are called cold currents as they bring cool water from the polar regions into the tropical regions. The cold current off the west coast of the United States is called the California Current.
Likewise, the opposite is true as well. Along the east coasts of the continents, the currents flow from the equator toward the poles. There are called warm current as they bring the warm tropical water north. The Gulf Stream, off the southeast United States coast, is one of the strongest currents known anywhere in the world, with water speeds up to 3 mph (5 kph).
These currents have a huge impact on the long-term weather a location experiences. The overall climate of Norway and the British Isle is about 18°F (10°C) warmer in the winter than other cites located at the same latitude due to the Gulf Stream.
Take it to the MAX! Keeping Current
While ocean currents are a shallow level circulations, there is global circulation which extends to the depths of the sea called the Great Ocean Conveyor. Also called the thermohaline circulation, it is driven by differences in the density of the sea water which is controlled by temperature (thermal) and salinity (haline).
In the northern Atlantic Ocean, as water flows north it cools considerably increasing its density. As it cools to the freezing point, sea ice forms with the "salts" extracted from the frozen water making the water below more dense. The very salty water sinks to the ocean floor.
Learning Lesson: That Sinking Feeling
It is not static, but a slowly southward flowing current. The route of the deep water flow is through the Atlantic Basin around South Africa and into the Indian Ocean and on past Australia into the Pacific Ocean Basin.
If the water is sinking in the North Atlantic Ocean then it must rise somewhere else. This upwelling is relatively widespread. However, water samples taken around the world indicate that most of the upwelling takes place in the North Pacific Ocean.
It is estimated that once the water sinks in the North Atlantic Ocean that it takes 1,000-1,200 years before that deep, salty bottom water rises to the upper levels of the ocean.
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In mathematics, hyperbolic functions are analogs of the ordinary trigonometric, or circular, functions. The basic hyperbolic functions are the hyperbolic sine "sinh" (typically pronounced /ˈsɪntʃ/ or /ˈʃaɪn/), and the hyperbolic cosine "cosh" (typically pronounced /ˈkɒʃ/), from which are derived the hyperbolic tangent "tanh" (typically pronounced /ˈtæntʃ/ or /ˈθæn/), etc., in analogy to the derived trigonometric functions. The inverse hyperbolic functions are the area hyperbolic sine "arsinh" (also called "asinh", or sometimes by the misnomer of "arcsinh") and so on.
Just as the points (cos t, sin t) form a circle with a unit radius, the points (cosh t, sinh t) form the right half of the equilateral hyperbola. Hyperbolic functions occur in the solutions of some important linear differential equations, for example the equation defining a catenary, and Laplace's equation in Cartesian coordinates. The latter is important in many areas of physics, including electromagnetic theory, heat transfer, fluid dynamics, and special relativity.
Hyperbolic functions were introduced in the 18th century by the Swiss mathematician Johann Heinrich Lambert.
The hyperbolic functions are:
Via complex numbers the hyperbolic functions are related to the circular functions as follows:
where is the imaginary unit defined as .
Note that, by convention, sinh2x means (sinhx)2, not sinh(sinhx); similarly for the other hyperbolic functions when used with positive exponents. Another notation for the hyperbolic cotangent function is , though cothx is far more common.
Hyperbolic sine and cosine satisfy the identity
which is similar to the Pythagorean trigonometric identity.
It can also be shown that the area under the graph of cosh x from A to B is equal to the arc length of cosh x from A to B.
For a full list of integrals of hyperbolic functions, see list of integrals of hyperbolic functions
In the above expressions, C is called the constant of integration.
It is possible to express the above functions as Taylor series:
A point on the hyperbola xy = 1 with x > 1 determines a hyperbolic triangle in which the side adjacent to the hyperbolic angle is associated with cosh while the side opposite is associated with sinh. However, since the point (1,1) on this hyperbola is a distance √2 from the origin, the normalization constant 1/√2 is necessary to define cosh and sinh by the lengths of the sides of the hyperbolic triangle.
and the property that cosh t ≥ 1 for all t.
The hyperbolic functions are periodic with complex period 2πi (πi for hyperbolic tangent and cotangent).
The parameter t is not a circular angle, but rather a hyperbolic angle which represents twice the area between the x-axis, the hyperbola and the straight line which links the origin with the point (cosh t, sinh t) on the hyperbola.
The function cosh x is an even function, that is symmetric with respect to the y-axis.
The function sinh x is an odd function, that is −sinh x = sinh(−x), and sinh 0 = 0.
The hyperbolic functions satisfy many identities, all of them similar in form to the trigonometric identities. In fact, Osborn's rule states that one can convert any trigonometric identity into a hyperbolic identity by expanding it completely in terms of integral powers of sines and cosines, changing sine to sinh and cosine to cosh, and switching the sign of every term which contains a product of 2, 6, 10, 14, ... sinhs. This yields for example the addition theorems
the "double angle formulas"
and the "half-angle formulas"
The derivative of sinh x is cosh x and the derivative of cosh x is sinh x; this is similar to trigonometric functions, albeit the sign is different (i.e., the derivative of cos x is −sin x).
The Gudermannian function gives a direct relationship between the circular functions and the hyperbolic ones that does not involve complex numbers.
The graph of the function a cosh(x/a) is the catenary, the curve formed by a uniform flexible chain hanging freely under gravity.
From the definitions of the hyperbolic sine and cosine, we can derive the following identities:
These expressions are analogous to the expressions for sine and cosine, based on Euler's formula, as sums of complex exponentials.
Since the exponential function can be defined for any complex argument, we can extend the definitions of the hyperbolic functions also to complex arguments. The functions sinh z and cosh z are then holomorphic.
Relationships to ordinary trigonometric functions are given by Euler's formula for complex numbers:
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Learn something new every day More Info... by email
A block diagram is a graphical method used to explain the concept of a system without the need to understand the individual components within that system. This type of diagram might be used in a variety of industries to illustrate and educate individuals about how a system operates, either in part or in its entirety. Block diagrams usually will have a logical, methodical flow from beginning to end. Engineers and software programmers are examples of individuals who might be familiar with block diagrams.
Block diagrams essentially are synonymous with flow charts, but a block diagram is generalized in nature. Sometimes block diagrams are used to conceal specific information or processes that might prove to be advantageous or detrimental, whichever the case might be. People who are being presented with a block diagram should be able to develop an understanding of what that block represents. To assist in understanding the block itself, lines should be drawn to the block representing various inputs, outputs or alternative choices.
Depending on the type of process being illustrated, blocks might serve in any capacity that is needed to adequately describe the process or parts of the process. For instance, a manufacturing cell of machine tools might include a drill press, a milling machine and a sanding machine. To illustrate a process within that cell, each machine tool might be represented by its own block. When the manufacturing process is illustrated in its entirety, a single block might be used to represent all of the components within that cell.
A block diagram also can be used to illustrate how a computer program works or how parts of a program work. If, for instance, a program is needed to calculate four different methods of interest rates, a block might represent each of these lines of code for one of these methods. In this way, a supervisor does not need to understand the code itself, as it is written, as long as the purpose of that block is communicated effectively.
Some block diagrams can be used as a way to map out a process as a top-down diagram. For instance, a person who has an inspired project might use a block diagram as a way to convey the idea as a series of individual blocks, each of which helps support the main topic. Later, these individual blocks might then be analyzed and further developed into additional block diagrams as needed. This method can be repeated until the process is mapped out to the satisfaction of all those involved with the project. If compiled and mapped out completely, the block diagram might resemble a pine tree type of structure of the entire project, which is typical for a top-down diagram.
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Researchers at Stanford University have brought about a unique marriage between computer chips and living cells that could greatly accelerate everything from tests for new drugs to screening for diseases such as leukemia.
The basic living element in every organism is the cell. Humans have at least 100 trillion of them, all designed to carry out various bodily functions. Each cell is a complex bag of enzymes and chemicals surrounded by a spherical membrane, and how a cell reproduces and works with other cells determines how efficiently the organism performs.
Scientists have struggled for years to understand the cell and especially the membrane that seems to control most of the crucial functions, but they have been hampered by the difficulty of growing cells in a laboratory culture for research.
A decade ago, Stanford researchers developed artificial membranes that were so like the real thing that living cells could be tricked into attaching themselves to them.
Two years ago, graduate student Jay T. Groves learned something interesting when he pulled a pair of tweezers through one of the artificial membranes. The parts separated permanently. He also found that he could manipulate the different parts by applying an electrical current.
About that time, Nick Ulman, an electrical engineer, joined Groves' research group, headed by chemistry professor Steven G. Boxer. Ulman brought with him an understanding of microelectronics.
The researchers discovered that the electric field generated by a tiny microchip could be used to separate the artificial membrane into tiny squares, which they called "corrals." The corrals were so small that millions occupied an area no bigger than a fingernail.
That gave the researchers something they had never had before: a means of isolating, cataloging and manipulating millions of cell membranes simultaneously.
"It's a little bit like having a parking lot with assigned spaces," Boxer says. If you leave your car in an unmarked parking lot at the airport, he says, you may be lucky to find it again. But if each parking space has a number, it becomes much simpler.
"Ultimately, you can say I've got a Ferrari in spot 2A, and I've got a Volkswagen over in space 3D," Boxer says.
Similarly, living cells can be "tricked" into attaching themselves to individual membranes. That is done by modifying the surface of each membrane.
"If you wax a car, after you wax it, water beads up on the surface," Boxer says. "Before waxing, the water just runs off. That's an example of modifying the properties of the surface such that water associates differently with the surface."
One potential use is for cell screening for leukemia patients. Some of the membranes on the chip could be "seeded" with proteins that bind to different kinds of cells. By flooding a glass plate embedded with chips with blood from the patient, the cells would attach themselves to designated areas, thus revealing how many cells of different types are present, and possibly even how well they are performing.
Joseph A. Zasadzinski, professor of chemical engineering at UC Santa Barbara, who has analyzed the Stanford research, sees many potential applications.
It could pave the way for a pharmaceutical researcher to "try 50 million different things" at the same time, Zasadzinski says.
"Right now, you grow cells in culture and you see which ones die, and that's very slow. Here you can imagine 20,000 little plates in a square inch, and each one of them you can tweak a slightly different way."
It could greatly increase the rate of testing for new drugs for viruses, he says, because the experiments could be repeated millions of times in a tightly controlled and manipulable environment.
Others see it leading to a test for AIDS in which thousands of blood tests could be conducted in the time it now takes to do just one.
The heart of the system is the computer chip.
"That's where the ultimate power of this comes in," Boxer says. "The same technology that's used to make integrated circuits, computer chips, is also being used to design a biocompatible surface."
That has led to a bit of unwelcome fallout, he adds. The researchers are constantly asked if they are on the road to the ultimate marriage between computers and living cells--the bionic man.
Boxer flinches at the suggestion. This is such a tiny step, he says, that it's ludicrous to think of it in those terms. Still, some see this as one more step toward creating computer-based biological systems.
"If you can optimize this, you can get a nice bio-sensor out of it," Zasadzinski says. "But it would be hard to imagine any sort of bionic man for an awful long time."
He says he is more worried about "that sheep in England."
"That's scary," he says.
Lee Dye can be reached via e-mail at firstname.lastname@example.org
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Hydrothermal circulation in its most general sense is the circulation of hot water; 'hydros' in the Greek meaning water and 'thermos' meaning heat. Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust. This generally occurs near volcanic activity, but can occur in the deep crust related to the intrusion of granite, or as the result of orogeny or metamorphism.
Seafloor hydrothermal circulation
The term includes both the circulation of the well known, high temperature vent waters near the ridge crests, and the much lower temperature, diffuse flow of water through sediments and buried basalts further from the ridge crests. The former circulation type is sometimes termed "active", and the latter "passive". In both cases the principle is the same: cold dense seawater sinks into the basalt of the seafloor and is heated at depth whereupon it rises back to the rock-ocean water interface due to its lesser density. The heat source for the active vents is the newly formed basalt, and, for the highest temperature vents, the underlying magma chamber. The heat source for the passive vents is the still-cooling older basalts. Heat flow studies of the seafloor suggest that basalts within the oceanic crust take millions of years to completely cool as they continue to support passive hydrothermal circulation systems.
Hydrothermal vents are locations on the seafloor where hydrothermal fluids mix into the overlying ocean. Perhaps the best known vent forms are the naturally-occurring chimneys referred to as black smokers.
Hydrothermal circulation is not limited to ocean ridge environments. The source water for hydrothermal explosions, geysers and hot springs is heated groundwater convecting below and lateral to the hot water vent. Hydrothermal circulating convection cells exist any place an anomalous source of heat, such as an intruding magma or volcanic vent, comes into contact with the groundwater system.
Deep crust
Hydrothermal also refers to the transport and circulation of water within the deep crust, generally from areas of hot rocks to areas of cooler rocks. The causes for this convection can be:
- Intrusion of magma into the crust
- Radioactive heat generated by cooled masses of granite
- Heat from the mantle
- Hydraulic head from mountain ranges, for example, the Great Artesian Basin
- Dewatering of metamorphic rocks which liberates water
- Dewatering of deeply buried sediments
Hydrothermal ore deposits
During the early 1900s various geologists worked to classify hydrothermal ore deposits which were assumed to have formed from upward flowing aqueous solutions. Waldemar Lindgren developed a classification based on interpreted decreasing temperature and pressure conditions of the depositing fluid. His terms: hypothermal, mesothermal, epithermal and teleothermal were based on decreasing temperature and increasing distance from a deep source. Only the epithermal has been used in recent works. John Guilbert's 1985 redo of Lindgren's system for hydrothermal deposits includes the following:
- Ascending hydrothermal fluids, magmatic or meteoric water
- Porphyry copper and other deposits, 200 - 800 °C, moderate pressure
- Igneous metamorphic, 300 - 800 °C, low - moderate pressure
- Cordilleran veins, intermediate to shallow depths
- Epithermal, shallow to intermediate, 50 - 300 °C, low pressure
- Circulating heated meteoric solutions
- Circulating heated seawater
- Oceanic ridge deposits, 25 - 300 °C, low pressure
See also
- W. Lindgren, 1933, Mineral Deposits, McGraw Hill, 4th ed.
- Guilbert, John M. and Charles F. Park, Jr., 1986, The Geology of Ore Deposits, Freeman, p. 302 ISBN 0-7167-1456-6
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Naval aviation is the application of military air power by navies, including ships that embark fixed-wing aircraft or helicopters. In contrast, maritime aviation is the operation of aircraft in a maritime role under the command of non-naval forces such as the former RAF Coastal Command or a nation's coast guard. An exception to this is the United States Coast Guard, which is considered part of U.S. naval aviation.
Naval aviation is typically projected to a position nearer the target by way of an aircraft carrier. Carrier aircraft must be sturdy enough to withstand demanding carrier operations. They must be able to launch in a short distance and be sturdy and flexible enough to come to a sudden stop on a pitching deck; they typically have robust folding mechanisms that allow higher numbers of them to be stored in below-decks hangars. These aircraft are designed for many purposes including air-to-air combat, surface attack, submarine attack, search and rescue, materiel transport, weather observation, reconnaissance and wide area command and control duties.
U.S. naval aviation began with pioneer aviator Glenn Curtiss who contracted with the Navy to demonstrate that airplanes could take off from and land aboard ships at sea. One of his pilots, Eugene Ely, took off from the USS Birmingham anchored off the Virginia coast in November 1910. Two months later Ely landed aboard another cruiser USS Pennsylvania in San Francisco Bay, proving the concept of shipboard operations. However, the platforms erected on those vessels were temporary measures. The U.S. Navy and Glenn Curtis experienced two firsts during January 1911. On January 27, Curtiss flew the first seaplane from the water at San Diego bay and the next day U.S. Navy Lt Theodore G. “Spuds” Ellyson, a student at the nearby Curtiss School, took off in a Curtiss “grass cutter” plane to become the first Naval aviator. Meanwhile, Captain Henry C. Mustin successfully designed the concept of the catapult launch, and in 1915 made the first catapult launching from a ship underway. Through most of World War I, the world's navies relied upon floatplanes and flying boats for heavier-than-air craft.
In January 1912, the British battleship HMS Africa took part in aircraft experiments at Sheerness. She was fitted for flying off aircraft with a 100-foot (30 m) downward-sloping runway which was installed on her foredeck, running over her forward 12-inch (305-mm) turret from her forebridge to her bows and equipped with rails to guide the aircraft. The Gnome-engined Short Improved S.27 "S.38", pusher seaplane piloted by Lieutenant Charles Samson become the first British aircraft to take-off from a ship while at anchor in the River Medway, on 10 January 1912. Africa then transferred her flight equipment to her sister ship Hibernia. In May 1912, with Commander Samson, again flying "S.38," first instance of an aircraft to take off from a ship which was underway occurred. Hibernia steamed at 10.5 knots (19 km/h) at the Royal Fleet Review in Weymouth Bay, England. Hibernia then transferred her aviation equipment to battleship London. Based on these experiments, the Royal Navy concluded that aircraft were useful aboard ship for spotting and other purposes, but that interference with the firing of guns caused by the runway built over the foredeck and the danger and impracticality of recovering seaplanes that alighted in the water in anything but calm weather more than offset the desirability of having airplanes aboard. However, shipboard naval aviation had begun in the Royal Navy, and would become a major part of fleet operations by 1917.
Other early operators of seaplanes were France, Germany and Russia. The foundations of Greek naval aviation were set in June 1912, when Lieutenant Dimitrios Kamberos of the Hellenic Aviation Service flew with the "Daedalus", a Farman Aviation Works aircraft that had been converted into a seaplane, at an average speed of 110 km per hour, achieving a new world record. Then, on January 24, 1913 the first wartime naval aviation interservice cooperation mission, took place above the Dardanelles. Greek Army First Lieutenant Michael Moutoussis and Greek Navy Ensign Aristeidis Moraitinis, on board the Maurice Farman hydroplane (floatplane/seaplane), drew a diagram of the positions of the Turkish fleet against which they dropped four bombs. This event was widely commented upon in the press, both Greek and international.
WWI and the first carrier strikes
The first strike from a carrier against a land target as well as a sea target took place in September 1914 when the Imperial Japanese Navy seaplane carrier Wakamiya conducted the world's first ship-launched air raids from Kiaochow Bay during the Battle of Tsingtao in China. The four Maurice Farman seaplanes bombarded German-held land targets (communication centers and command centers) and damaged a German minelayer in the Tsingtao peninsula from September until November 6, 1914, when the Germans surrendered.
On the Western front the first naval air raid occurred on December 25, 1914 when twelve seaplanes from HMS Engadine, Riviera and Empress (cross-channel steamers converted into seaplane carriers ) attacked the Zeppelin base at Cuxhaven. Fog, low cloud and anti-aircraft fire prevented the raid from being a complete success, but the raid demonstrated the feasibility of attack by ship-borne aircraft and showed the strategic importance of this new weapon.
Development in the Interwar period
Genuine aircraft carriers did not emerge beyond Britain until the early 1920s.
In the United States, Billy Mitchell's 1921 demonstration of the battleship-sinking ability of land-based heavy bombers made many United States Navy admirals angry. However, some men, such as Captain (soon Rear Admiral) William A. Moffett, saw the publicity stunt as a means to increase funding and support for the Navy's aircraft carrier projects. Moffett was sure that he had to move decisively in order to avoid having his fleet air arm fall into the hands of a proposed combined Land/Sea Air Force which took care of all the United States's airpower needs. (That very fate had befallen the two air services of the United Kingdom in 1918: the Royal Flying Corps had been combined with the Royal Naval Air Service to become the Royal Air Force, a condition which would remain until 1937.) Moffett supervised the development of naval air tactics throughout the '20s.
Many British naval vessels carried float planes, seaplanes or amphibians for reconnaissance and spotting: two to four on battleships or battlecruisers and one on cruisers. The aircraft, a Fairey Seafox or later a Supermarine Walrus, were catapult-launched, and landed on the sea alongside for recovery by crane. Several submarine aircraft carriers were built by Japan. The French Navy built one large (but ineffective) aircraft carrying submarine, the Surcouf.
World War II
World War II saw the emergence of naval aviation as a significant, often decisive, element in the war at sea. The principal users were Japan, United States (both with Pacific interests to protect) and the United Kingdom. Other colonial powers, e.g. France and the Netherlands, showed a lesser interest. Other powers such as Germany and Italy did not develop independent naval aviation, for geographic or political reasons. Soviet Naval Aviation was mostly organized as land-based coast defense force (apart from some scout floatplanes it consisted almost exclusively of land-based types also used by the Air Force and Air defence units).
During the course of the war, seaborne aircraft were used in fleet actions at sea (Battle of Midway, Bismarck), pre-emptive strikes against naval units in port (Battle of Taranto, Attack on Pearl Harbor), support of ground forces (Battle of Okinawa, Allied invasion of Italy) and anti-submarine warfare (the Battle of the Atlantic). Carrier-based aircraft were specialized as dive bombers, torpedo bombers, and fighters. Surface-based aircraft such as the PBY Catalina helped finding submarines and surface fleets.
In WWII the aircraft carrier replaced the battleship as the most powerful naval offensive weapons system as battles between fleets were increasingly fought out of gun range by aircraft. The Japanese Yamato, the most powerful battleship ever built, was first turned back by light escort carrier aircraft and later sunk lacking its own air cover.
The US launched normally land-based bombers from carriers in a raid against Tokyo. Smaller carriers were built in large numbers to escort slow cargo convoys or supplement fast carriers. Aircraft for observation or light raids were also carried by battleships and cruisers, while blimps were used to search for attack submarines.
Experience showed that there was a need for widespread use of aircraft which could not be met quickly enough by building new fleet aircraft carriers. This was particularly true in the north Atlantic, where convoys were highly vulnerable to U-boat attack. The British authorities used unorthodox, temporary, but effective means of giving air protection such as CAM ships and merchant aircraft carriers, merchant ships modified to carry a small number of aircraft. The solution to the problem were large numbers of mass-produced merchant hulls converted into escort aircraft carriers (also known as "jeep carriers"). These basic vessels, unsuited to fleet action by their capacity, speed and vulnerability, nevertheless provided air cover where it was needed.
The Royal Navy had observed the impact of naval aviation and, obliged to prioritise their use of resources, abandoned battleships as the mainstay of the fleet. HMS Vanguard was therefore the last British battleship and her sisters were cancelled. The United States had already instigated a large construction programme (which was also cut short) but these large ships were mainly used as anti-aircraft batteries or for shore bombardment.
Other actions involving naval aviation included:
- Battle of the Atlantic, aircraft carried by low-cost escort carriers were used for antisubmarine patrol, defense, and attack.
- At the start of the Pacific War in 1941, Japanese carrier-based aircraft sank many US warships at Pearl Harbor and land-based aircraft sank two large British warships. Engagements between Japanese and American naval fleets were then conducted largely or entirely by aircraft - examples include the battles of Coral Sea, Midway, Bismarck Sea and Philippine Sea.
- Battle of Leyte Gulf, with the first appearance of kamikazes, perhaps the largest naval battle in history. Japan's last carriers and pilots are deliberately sacrificed, a battleship is sunk by aircraft.
- Operation Ten-Go demonstrated U.S. air supremacy in the Pacific theater by this stage in the war and the vulnerability of surface ships without air cover to aerial attack.
Strategic projection
Carrier-based naval aviation provides a country's seagoing forces with air cover over areas that may not be reachable by land-based aircraft, giving them a considerable advantage over navies composed primarily of surface combatants.
In the case of the United States Navy during and after the Cold War, virtual command of the sea in many of the world's waterways allowed it to deploy aircraft carriers and project air power almost anywhere on the globe. By operating from international waters, U.S. carriers can bypass the need for conventional airbases or overflight rights, both of which can be politically difficult to acquire.
During the Cold War, the navies of NATO faced a significant threat from Soviet submarine forces, specifically Soviet Navy SSN and SSGN assets. This resulted in the development and deployment of light aircraft carriers with major anti-submarine warfare (ASW) capabilities by European NATO navies. One of the most effective weapons against submarines is the ASW helicopter, several of which could be based on these light aircraft carriers. These light carriers were typically around 20,000 tons displacement and carried a mix of ASW helicopters and BAe Sea Harrier or Harrier II V/STOL aircraft.
- Argentine Naval Aviation
- Brazilian Naval Aviation
- Fleet Air Arm (RAN)
- Fleet Air Arm (Royal Navy)
- French Naval Aviation
- Indian Naval Air Arm
- Marineflieger (German navy)
- Mexican Naval Aviation
- Pakistan Naval Air Arm
- People's Liberation Army Naval Air Force
- Peruvian Naval Aviation
- Russian Naval Aviation
- United States Naval Aviator
See also
- Military aviation
- Aircraft carrier
- Escort carrier
- Carrier-based aircraft
- Flying boat
- Aerial warfare
- Modern US Navy carrier air operations
- Hellenic Air Force History - The first Steps
- Hellenic Air Force History - Balcan Wars
- Wakamiya is "credited with conducting the first successful carrier air raid in history"Source:GlobalSecurity.org, also "the first air raid in history to result in a success" (here)
- "Sabre et pinceau", Christian Polak, p92
- IJN Wakamiya Aircraft Carrier
- Boyne (2003), pp.227–8
- Clark G. Reynolds, The fast carriers: the forging of an air navy (1968; 1978; 1992)
- William F. Trimble, Hero of the Air: Glenn Curtiss and the Birth of Naval Aviation (2010)
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Science Fair Project Encyclopedia
Trier (French: Trèves), is Germany's oldest city. It is situated on the western bank of the Moselle River in a valley between low vine-covered hills of ruddy sandstone. It is located in the state of Rhineland-Palatinate near the German border with Luxembourg. Trier had around 100,000 inhabitants at the end of 2002. There is also an important wine-growing-region nearby: Mosel-Saar-Ruwer.
The Romans under Julius Caesar subdued the Celtic Treverans in 58 to 50 BC. When the Roman provinces in Germany were reorganised in 16 BC, Augustus decided that Trier, then called Augusta Treverorum, should become the regional capital. From 259 to 274 Trier was the capital of the break away Gallic Empire. Later for a few years (383 - 388) it was the capital of Magnus Maximus, who ruled most of the western Empire.
Sacked by Attila in 451, it passed to the Franks in 463, to Lorraine in 843, to Germany in 870, and back to Lorraine in 895, and was finally united to Germany by the Emperor Henry I. The Archbishop of Trier was, as chancellor of Burgundy, one of the electors of the empire, a right which originated in the 12th or 13th century, and which continued till the French Revolution. The last elector removed to Koblenz in 1786; and Treves was the capital of the French department of Sarre from 1794 till 1814, after which time it belonged to Prussia.
The city is well known for its well-preserved Roman buildings, among them the Porta Nigra, the best preserved Roman city gate north of the Alps, a complete amphitheatre, ruins of several Roman baths, and the huge Basilica, a basilica in the original Roman sense, being the 67m-length throne hall of Roman Emperor Constantine; it is today used as a Protestant church.
Trier is the oldest seat of a Christian bishop in Germany. In the Middle Ages, the Archbishop of Trier was an important ecclesiastical prince, controlling land from the French border to the Rhine. He was also one of the seven electors of the Holy Roman Empire.
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details
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Surface area is a two-dimensional property of a three-dimensional figure. Cones are similar to pyramids, except they have a circular base instead of a polygonal base. Therefore, the surface area of a cone is equal to the sum of the circular base area and the lateral surface area, calculated by multiplying half of the circumference by the slant height. Related topics include pyramid and cylinder surface area.
If you want to calculate the surface area of a cone, you only need to know 2 dimensions. The first is the slant height l and the second is the radius. So what we're going to do, we're going to separate this into two pieces the first is the base which is a circle with radius r and the second is this slant height l. So if I cut, if I took a scissors and cut the cone part and I fended out it would look like a sector. Well what I could do here is I could rearrange this sector into a parallelogram. So again if I cut this into really tiny pieces then I'll be able to organize it into a parallelogram where I would be able to calculate its area. And the way that we'll calculate its area, is first by saying well what are these lines that are going out?
Well those lines are going to be your l, your slant height and this side right here is going to be half of your circumference and half of a circumference is pi times r because the whole circumference is 2 pi r. So this down here is pi times r, so if our height l and our base is pi times r then the area of this is equal to pi times r times l. So the surface area of a cone which I'm going to write over here is equal to the base pi r squared plus this lateral area which is found using your slant height. So that's going be pi times r times l, so you only need to know 2 dimensions the radius and the slant height and you can calculate the surface area of any cone.
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Use the Activities
Putting It All Together
All the events prior to and during the American Revolutionary War in central New York are interrelated, and these had profound effects on the people who lived there. In these activities, students will compare their lives in their community to what it would be like to live in central New York during this time. Students will also explore what it was like to be at the Battle of Oriskany.
Activity 1: Where Do I Stand?
Ask each student to select one of the historical people who participated at the Battle of Oriskany and create a report in the character of that person about the experience.
The report may be written or oral. Once the student has identified what person they are portraying and explained why that character was selected, the student should answer the following questions in character:
1. What do you (the person you are roleplaying) believe in? What do you support?
2. What do you oppose?
3. What are your hopes and dreams?
4. What are you feeling before this battle? Are you angry, sad, happy or a mixture of these? Are you worried or anxious about yourself and your family? Are you optimistic or pessimistic about the outcome of the battle?
5. Place yourself in the battle. Where are you located, in the ravine or on the hilltop? What do you see, hear, smell and feel? Who do you see? What are you doing? What are your feelings? Are you afraid, angry, or confused or a mixture?
6. After the battle, how do you feel? Are you worried or anxious about your family? What do you see in your immediate or long-term future? Has your outlook changed? Have your hopes and ambitions changed? Are you optimistic or pessimistic about the future?
Activity 2: The Lost Battlefield
The Oriskany Battlefield has been lost over time. The land is still there, however, the old Military Road is gone, the virgin woodland forest has been clear cut, and exact placements of everyone on the battlefield can not be reproduced. Except for letter and journal entries, some written shortly after the battle and others collected long after the battle (which sometimes are conflicting) there is little to tell us exactly where and how the battle was fought. There is also little physical evidence available to help researchers evaluate the reliability of these accounts.
Students are going to be asked to recreate the Battle of Oriskany. They should keep a written journal or recorded oral log about the investigative and production phases of the project. After students have completed studying the quotes in the readings, looked at maps of the area or colonial illustrations depicting military clothing and weapons, and completed additional personal research, ask them to complete one of the following activities:
1. As an historical cartographer, find the ravine and high ground, and then draw a map or series of maps of Oriskany battlefield during the battle's different phases.
2. As an historical illustrator, sketch or paint a picture or series of pictures of the Battle of Oriskany.
3. As a re-enactor or documentary film-maker, create costumes, re-enact the
battle, and videotape the re-enactment. Edit the tape and add voice-over
narration for final presentation.
Activity 3: In the Grip of Fear
Ask the students to produce a written, pictorial, or video report describing a controversial issue which has divided their community. Point out that community can be interpreted in many ways and may be their school, sports teams, parent groups, school board, local government, or state government as well as the nation or world. The students will have to use investigative research techniques and questioning strategies to find the answers through review of local newspapers, committee reports, and personal interviews. Students may want to record their data on a chart like the one used in Reading 1. Ask them to identify what the controversy is, and then answer the following questions:
1. Is there only one central issue that is causing the controversy, or are there several issues?
2. What was the history of the community before the controversy? Are there events in the past which affect the issue(s) today?
3. Who are the key leaders on both sides of the issue? Why have they taken the stand they have taken?
4. What is the general social make-up of the followers of these leaders? Where are they from? In which part of the community do they live? What is their social, political and economic standing? What are their race, ethnicity, and sex? What types of jobs do they have? Where do they stand on the issue and why?
After the students have completed this activity, have them ask the same questions about the Mohawk Valley civil war and then compare and contrast the contemporary controversy they have studied with the Mohawk Valley civil war. Alternatively, the students may want to compare the controversy they have studied with the U.S. Civil War, regional civil wars in the U.S. (such as in "Bleeding Kansas"), or civil wars on the international scene (such as in Rwanda and Kosovo in the 1990s or China in the 1940s).
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In this lecture you will learn how to undertake Solving Quadratic Systems. First you will start with Linear Quadratic Systems as well as their Solutions, before you move into Quadratic Quadratic Systems and their Solutions. Lastly, you will learn how to solve Systems of Quadratic Inequalities.
linear-quadratic system, use substitution to solve.
quadratic-quadratic system, use elimination to solve.
inequalities, remember the conventions about graphing boundaries
using either solid or dotted lines.
If possible, check
your solutions to systems of equations by graphing.
Solving Quadratic Systems
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
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Magnetic Resonance Imaging (MRI)
Magnetic resonance imaging (MRI) is a test that uses a magnetic field and pulses of radio wave energy to make pictures of organs and structures inside the body. In many cases MRI gives different information about structures in the body than can be seen with an X-ray, ultrasound, or computed tomography (CT) scan. MRI also may show problems that cannot be seen with other imaging methods.
For an MRI test, the area of the body being studied is placed inside a special machine that contains a strong magnet. Pictures from an MRI scan are digital images that can be saved and stored on a computer for more study. The images also can be reviewed remotely, such as in a clinic or an operating room. In some cases, contrast material may be used during the MRI scan to show certain structures more clearly.
Why It Is Done
Magnetic resonance imaging (MRI) is done for many reasons. It is used to find problems such as tumors, bleeding, injury, blood vessel diseases, or infection. MRI also may be done to provide more information about a problem seen on an X-ray, ultrasound scan, or CT scan. Contrast material may be used during MRI to show abnormal tissue more clearly. An MRI scan can be done for the:
How To Prepare
Before your MRI test, tell your doctor and the MRI technologist if you:
You may need to arrange for someone to drive you home after the test, if you are given a medicine (sedative) to help you relax.
For an MRI of the abdomen or pelvis, you may be asked to not eat or drink for several hours before the test.
You may need to sign a consent form that says you understand the risks of an MRI and agree to have the test done. Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).
How It Is Done
A magnetic resonance imaging (MRI) test is usually done by an MRI technologist. The pictures are usually interpreted by a radiologist. But some other types of doctors can also interpret an MRI scan.
You will need to remove all metal objects (such as hearing aids, dentures, jewelry, watches, and hairpins) from your body because these objects may be attracted to the powerful magnet used for the test.
You will need to take off all or most of your clothes, depending on which area is examined (you may be allowed to keep on your underwear if it is not in the way). You will be given a gown to use during the test. If you are allowed to keep some of your clothes on, you should empty your pockets of any coins and cards (such as credit cards or ATM cards) with scanner strips on them because the MRI magnet may erase the information on the cards.
During the test you usually lie on your back on a table that is part of the MRI scanner. Your head, chest, and arms may be held with straps to help you remain still. The table will slide into the space that contains the magnet. A device called a coil may be placed over or wrapped around the area to be scanned. A special belt strap may be used to sense your breathing or heartbeat. This triggers the machine to take the scan at the right time.
Some people feel nervous (claustrophobic) inside the MRI magnet. If this keeps you from lying still, you can be given a medicine (sedative) to help you relax. Some MRI machines (called open MRI) are now made so that the magnet does not enclose your entire body. Open MRI machines may be helpful if you are claustrophobic, but they are not available everywhere. The pictures from an open MRI may not be as good as those from a standard MRI machine. See pictures of a standard MRI machine and an open MRI machine.
Inside the scanner you will hear a fan and feel air moving. You may also hear tapping or snapping noises as the MRI scans are taken. You may be given earplugs or headphones with music to reduce the noise. It is very important to hold completely still while the scan is being done. You may be asked to hold your breath for short periods of time.
During the test, you may be alone in the scanner room. But the technologist will watch you through a window. You will be able to talk with the technologist through a two-way intercom.
If contrast material is needed, the technologist will put it in an intravenous (IV) line in your arm. The material may be given over 1 to 2 minutes. Then more MRI scans are done.
An MRI test usually takes 30 to 60 minutes but can take as long as 2 hours.
How It Feels
You will not have pain from the magnetic field or radio waves used for the MRI test. The table you lie on may feel hard and the room may be cool. You may be tired or sore from lying in one position for a long time.
If a contrast material is used, you may feel some coolness and flushing as it is put into your IV.
In rare cases, you may feel:
There are no known harmful effects from the strong magnetic field used for MRI. But the magnet is very powerful. The magnet may affect pacemakers, artificial limbs, and other medical devices that contain iron. The magnet will stop a watch that is close to the magnet. Any loose metal object has the risk of causing damage or injury if it gets pulled toward the strong magnet.
Metal parts in the eyes can damage the retina. If you may have metal fragments in the eye, an X-ray of the eyes may be done before the MRI. If metal is found, the MRI will not be done.
Iron pigments in tattoos or tattooed eyeliner can cause skin or eye irritation.
An MRI can cause a burn with some medication patches. Be sure to tell your health professional if you are wearing a patch.
There is a slight risk of an allergic reaction if contrast material is used during the MRI. But most reactions are mild and can be treated using medicine. There also is a slight risk of an infection at the IV site.
A magnetic resonance imaging (MRI) is a test that uses a magnetic field and pulses of radio wave energy to make pictures of organs and structures inside the body.
The radiologist may discuss initial results of the MRI with you right after the test. Complete results are usually ready for your doctor in 1 to 2 days.
An MRI can sometimes find a problem in a tissue or organ even when the size and shape of the tissue or organ looks normal.
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include:
Many modern medical devices that do not use electronics—such as heart valves, stents, or clips—can be safely placed in most MRI machines. But some newer MRI machines have stronger magnets. The safety of MRI scans with these stronger MRI magnets in people with medical devices is not known.
What To Think About
eMedicineHealth Medical Reference from Healthwise
To learn more visit Healthwise.org
© 1995-2012 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
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In 2006, high sea temperatures caused severe coral bleaching in the Keppell Islands, in the southern part of the reef — the largest coral reef system in the world. The damaged reefs were then covered by a single species of seaweed which threatened to suffocate the coral and cause further loss.
A "lucky combination" of rare circumstances has meant the reef has been able to make a recovery. Abundant corals have reestablished themselves in a single year, say the researchers from the University of Queensland's Centre for Marine Studies and the ARC Centre of Excellence for Coral Reef Studies (CoECRS).
"Three factors were critical," said Dr Guillermo Diaz-Pulido. "The first was exceptionally high regrowth of fragments of surviving coral tissue. The second was an unusual seasonal dieback in the seaweeds, and the third was the presence of a highly competitive coral species, which was able to outgrow the seaweed."
Coral bleaching occurs in higher sea temperatures when the coral lose the symbiotic algae they need to survive. The reefs then lose their colour and become more susceptible to death from starvation or disease.
The findings are important as it is extremely rare to see reports of reefs that bounce back from mass coral bleaching or other human impacts in less than a decade or two, the scientists said. The study is published in the online journal PLoS one.
"The exceptional aspect was that corals recovered by rapidly regrowing from surviving tissue," said Dr Sophie Dove, also from CoECRS and The University of Queensland.
"Recovery of corals is usually thought to depend on sexual reproduction and the settlement and growth of new corals arriving from other reefs. This study demonstrates that for fast-growing coral species asexual reproduction is a vital component of reef resilience."
Last year, a major global study found that coral reefs did have the ability to recover after major bleaching events, such as the one caused by the El Niño in 1998.
David Obura, the chairman of the International Union for Conservation of Nature climate change and coral reefs working group involved with the report, said: "Ten years after the world's biggest coral bleaching event, we know that reefs can recover – given the chance. Unfortunately, impacts on the scale of 1998 will reoccur in the near future, and there's no time to lose if we want to give reefs and people a chance to suffer as little as possible."
Coral reefs are crucial to the livelihoods of millions of coastal dwellers around the world and contain a huge range of biodiversity. The UN's Millennium Ecosystem Assessment says reefs are worth about $30bn annually to the global economy through tourism, fisheries and coastal protection.
But the ecosystems are under threat worldwide from overfishing, coastal development and runoff from the land, and in some areas, tourism impacts. Natural disasters such as the earthquake that triggered the Indian Ocean tsunami in 2004 have also caused reef loss.
Climate change poses the biggest threat to reefs however, as emissions of carbon dioxide make seawater increasingly acidic.
Last year a study showed that one-fifth of the world's coral reefs have died or been destroyed and the remainder are increasingly vulnerable to the effects of climate change.
The Global Coral Reef Monitoring Network says many surviving reefs could be lost over the coming decades as CO2 emissions continue to increase.
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Earth from Space: Easter Island
Easter Island as seen by astronauts aboard the International Space Station on Sept. 25, 2002.
On Easter Sunday in 1722, Dutch explorer Jacob Roggeveen became the first known European to encounter this Polynesian island and gave it the name it has become most widely known by.
Easter Island (also known as Rapa Nui in the native language) is one of the most isolated spots on Earth, lying some 2,000 miles from the nearest areas of human habitation (Tahiti and Chile) — even more remote than the astronauts orbiting at 210 nautical miles above the Earth.. The island, which is only 15 miles long, was annexed by Chile in 1888. (In Spanish, it is called "Isla de Pascua," which means "Easter Island.")
Archaeological evidence suggests that Polynesians from other Pacific Islands discovered and colonized Easter Island around the year 400.
The island and its early inhabitants are best known for the giant stone monoliths, known as Moai, placed along the coastline.
It is thought that the population grew bigger than was sustainable on the small island, resulting in civil war, deforestation and near collapse of the island ecosystem . Today, a new forest (primarily eucalyptus) has been established in the center of the island (the dark green in the image), according to a NASA statement.
Volcanic landforms dominate the geography of the island, including the large crater Rana Kao at the southwest end of the island and a line of cinder cones that stretch north from the central mountain. Near Rana Kao is the longest runway in Chile, which served as an emergency landing spot for the space shuttle before its retirement in 2011.
MORE FROM LiveScience.com
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High blood pressure, or hypertension, affects almost one in three adults in the United States. However, this serious health condition isn't limited to just those ages 18 and older.
The number of children and adolescents with high blood pressure is increasing. This rise can be partly blamed on the increasing number of overweight and obese children.
High blood pressure is a major risk factor for heart disease and is the primary risk factor for stroke. Prehypertension is a condition that increases a child's risk of developing high blood pressure in the future. Children with hypertension have a higher risk for high blood pressure as adults. High blood pressure in childhood is also correlated with early development of atherosclerosis in adulthood.
Systolic pressure is the top number in a blood pressure reading and corresponds to the pressure in arteries when the heart contracts. Diastolic pressure is the bottom number in a blood pressure reading, and corresponds to the pressure in the arteries between heart beats, when the heart relaxes.
The American Academy of Pediatrics recommends that children ages 3 years and older have their blood pressure measured each time they see their health care provider for routine checkups. Normal blood pressure in children depends on their gender, age, and height.
Parents and health care providers encourage children with high blood pressure to make lifestyle changes, such as losing weight. Other changes may include increased exercise and improved diet. A doctor may also give a child prescription medication to help control blood pressure.
Regular exercise helps control weight and may keep blood pressure in check. Regular exercise means 30 to 60 minutes of moderate physical activity on most days. Sedentary activities should be limited to less than two hours a day.
A healthy diet for a child with prehypertension or high blood pressure includes fresh vegetables and fruits, additional fiber, and nonfat dairy products, as well as limited salt and sodium. The American Heart Association recommends a maximum daily sodium intake of 1,500 mg/day; however, this number may be lower, depending on your child's age and other health considerations. Please consult your child's pediatrician regarding the recommended sodium intake for your child.
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During this tutorial you will be asked to perform calculations involving trigonometric functiions. You will need a calulator to proceed.
| The purpose of this tutorial
is to review with you the elementary properties of the trigonometric functions.
Facility with this subject is essential to success in all branches of science,
and you are strongly urged to review and practice the concepts presented
here until they are mastered. Let us consider the right-angle triangle
shown in Panel 1. The angle at C is a right angle and the angle
A we will call θ. The lengths of the
sides of the triangle we will denote as p, q and r. From your elementary
geometry, you know several things about this triangle. For example, you
know the Pythagorean relation,
q² = p² + r². That is, the square of the length of the side opposite the right angle, which we call the hypotenuse, is equal to the sum of the squares of the lengths of the other two sides.
We know other things. For example, we know that if the lengths of the three sides of any triangle p, q and r are specified, then the whole triangle is determined, angles included. If you think about this for a moment, you will see it is correct. If I give you three sticks of fixed length and told you to lay them down in a triangle, there's only one triangle which you could make. What we would like to have is a way of relating the angles in the triangle, say θ, to the lengths of the sides.
It turns out that there's no simple analytic way to do this. Even though the triangle is specified by the lengths of the three sides, there is not a simple formula that will allow you to calculate the angle θ. We must specify it in some new way.
|To do this, we define three ratios of the sides of the triangle.
One ratio we call the sine of theta, written sin(θ), and it is defined as the ratio of the side opposite θ to the hypotenuse, that is r/q.
The cosine of θ, written cos(θ), is the side adjacent to θ over the hypotenuse, that is, p/q.
This is really enough, but because it simplifies our mathematics later on, we define the tangent of θ, written tan(θ), as the ratio of the opposite to the adjacent sides, that is r/p. This is not an independent definition since you can readily see that the tangent of θ is equal to the sine of θ divided by the cosine of θ. Verify for yourself that this is correct.
All scientific calculators provide this information. The first thing to ensure is that your calculator is set to the anglular measure that you want. Angles are usually measured in either degrees or radians (see tutorial on DIMENSIONAL ANALYSIS). The angle 2º is a much different angle than 2 radians since 180º = π radians = 3.1416... radians. Make sure that your calculator is set to degrees.
Now suppose that we want the sine of 24º. Simply press 24 followed by the [sin] key and the display should show the value 0.4067. Therefore, the sine of 24º is 0.4067. That is, in a triangle like panel 1 where θ = 24º, the ratio of the sides r to q is 0.4067. Next set your calculator to radians and find the sine of 0.42 radians. To do this enter 0.42 followed by the [sin] key. You should obtain a value of 0.4078. This is nearly the same value as you obtained for the sine of 24º. Using the relation above you should confirm that 24º is close to 0.42 radians
Obviously, using your calculator to find values of sines is very simple. Now find sine of 42º 24 minutes. The sine of 42º 24 minutes is 0.6743. Did you get this result? If not, remember that 24 minutes corresponds to 24/60 or 0.4º. The total angle is then 42.4º
| The determination of
cosines and tangents on your calculator is similar. It is now possible
for us to solve the simple problem concerning triangles. For example, in
Panel 2, the length of the hypotenuse is 3 cm and the angle θ
is 24º. What is the length of the opposite side r? The sine of 24º
as we saw is 0.4067 and it is also, by definition, r/3.
So, sine of 24º = .4067 = r/3, and therefore, r = 3 x 0.4067 = 1.22 cm.
|Conversely, suppose you knew that the opposite side was
2 cm long and the hypotenuse was 3 cm long, as in panel 3, what is the
angle θ? First determine the sine of θ
You should find that the sine of θ is 2/3, which equals 0.6667. Now we need determine what angle has 0.6667 as its sine.
If you want your answer to be in degrees, be sure that your calculator is set to degrees. Then enter 0.6667 followed by the [INV] key and then the [sin] key. You should obtain a value of 41.8º. If your calculator doesn't have a [INV] key, it probably has a [2ndF] key and the inverse sine can be found using it.
|One use of these trigonometric functions which is very important is the calculation of components of vectors. In panel 4 is shown a vector OA in an xy reference frame. We would like to find the y component of this vector. That is, the projection OB of the vector on the y axis. Obviously, OB = CA and CA/OA = sin(θ), so CA = OA sin(θ). Similarly, the x-component of OA is OC. And OC/OA = cos(θ) so OC = OA cos(θ).|
|There are many relations among the trigonometric functions
which are important, but one in particular you will find used quite often.
Panel 1 has been repeated as Panel 5 for you. Let us look at the sum cos²
+ sin². From the figure, this is (p/q)² + (r/q)², which
[(p² + r²) / (q²)]. The Pythagorean theorem tells us that p² + r² = q² so we have
[(p² + r²) / q²] = (q²/q²) = 1. Therefore, we have;
Our discussion so far has been limited to angles between 0 and 90º. One can, using the calculator, find the the sine of larger angles (eg 140º ) or negative angles (eg -32º ) directly. Sometimes, however, it is useful to find the corresponding angle betweeen 0 and 90º. Panel 6 will help us here.
|In this xy reference frame, the angle θ
is clearly between 90º and 180 º, and clearly, the angle a,
which is 180 - θ
( a is marked with a double arc) can be dealt with. In this case, we say that the magnitude of sine, cosine, and tangent of θ are those of the supplement a and we only have to examine whether or not they are positive or negative.
For example, what is the sine, cosine and tangent of 140º? The supplement is 180º - 140º = 40º. Find the sine, the cosine and the tangent of 40º.
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Let's Talk About: Cosmic collisions
Share with others:
It has been almost 100 years since Edwin Hubble measured the universe beyond the Milky Way Galaxy. Today, astronomers believe that as many as 100 billion other galaxies are sharing the cosmos. Most of these cosmic islands are classified by shape as either spiral or elliptical, but stargazing scientists have discovered galaxies that don't quite fit these molds.
Common to this "irregular" category are galaxies that interact with other galaxies. These gravitational interactions are often referred to as mergers, and their existence invites the question: Is the Milky Way collision-prone? To evaluate the probability, look to the Andromeda Galaxy. Located more than 2.5 million light-years away, Andromeda appears as a small fuzzy patch in the sky. However, there is nothing miniature about it. Similar to the shape (spiral), size and mass of the Milky Way, Andromeda is home to a trillion other stars.
Astronomers have known for decades that our galactic neighbor is rapidly closing in on us -- at approximately 250,000 miles per hour. They know this because of blueshift, a measured decrease in electromagnetic wavelength caused by the motion of a light-emitting source, in this case Andromeda, as it moves closer to the observer.
Recently, data collected from the Hubble Space Telescope has allowed astronomers to predict a merger with certainty, in 4 billion years. Our sun will still be shining, and Earth will most likely survive the impact. Reason being, galaxies, although single units of stars gravitationally tied together, are mostly gigantic voids. One can compare a galaxy-on-galaxy collision to the pouring of one glass of water into another. The end result is a larger collection of water, or in the case of a cosmic collision, a larger galaxy. Future Earth inhabitants, billions of years from now, could look up and observe only small portions of such an event because it will take 2 billion years for these cosmic islands to become one.
First Published November 29, 2012 12:00 am
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Modeling is the process of taking a shape and molding it into a completed 3D mesh. The most typical means of creating a 3D model is to take a simple object, called a primitive, and extend or “grow” it into a shape that can be refined and detailed. Primitives can be anything from a single point (called a vertex), a two-dimensional line (an edge), a curve (a spline), to three dimensional objects (faces or polygons).
Using the specific features of your chosen 3D software, each one of these primitives can be manipulated to produce an object. When you create a model in 3D, you’ll usually learn one method to create your model, and go back to it time and again when you need to create new models. There are three basic methods you can use to create a 3D model, and 3D artists should understand how to create a model using each technique.
1. Spline or patch modeling: A spline is a curve in 3D space defined by at least two control points. The most common splines used in 3D art are bezier curves and NURBS (the software Maya has a strong NURBS modeling foundation.) Using splines to create a model is perhaps the oldest, most traditional form of 3D modeling available. A cage of splines is created to form a “skeleton” of the object you want to create. The software can then create a patch of polygons to extend between two splines, forming a 3D skin around the shape. Spline modeling is not used very often these days for character creation, due to how long it takes to create good models. The models that are produced usually aren’t useful for animation without a lot of modification.
Spline modeling is used primarily for the creation of hard objects, like cars, buildings, and furniture. Splines are extremely useful when creating these objects, which may be a combination of angular and curved shapes. When creating a 3D scene that requires curved shapes, spline modeling should be your first choice.
2. Box modeling: Box modeling is possibly the most popular technique, and bears a lot of resemblance to traditional sculpting. In box modeling, one starts with a primitive (usually a cube) and begins adding detail by “slicing” the cube into pieces and extending faces of the cube to gradually create the form you’re after. People use box modeling to create the basic shape of the model. Once practiced, the technique is very quick to get acceptable results. The downside is that the technique requires a lot of tweaking of the model along the way. Also, it is difficult to create a model that has a surface topology that lends well to animation.
Box modeling is useful as a way to create organic models, like characters. Box modelers can also create hard objects like buildings, however precise curved shapes may be more difficult to create using this technique.
3. Poly modeling / edge extrusion: While it’s not the easiest to get started with, poly modeling is perhaps the most effective and precise technique. In poly modeling, one creates a 3D mesh point-by-point, face-by-face. Often one will start out with a single quad (a 3D object consisting of 4 points) and extrude an edge of the quad, creating a second quad attached to the first. The 3D model is created gradually in this way. While poly modeling is not as fast as box modeling, it requires less tweaking of the mesh to get it “just right,” and you can plan out the topology for animation ahead of time.
Poly modelers use the technique to create either organic or hard objects, though poly modeling is best suited for organic models.
A Workflow that Works
The workflow you choose to create a model will largely depend on how comfortable you are with a given technique, what object you’re creating, and what your goals are for the final product.
Someone who is creating an architectural scene, for example, may create basic models with cubes and other simple shapes to create an outline of the finished project. Meshes can then be refined or replaced with more detailed objects as you progress through the project. This is an organized, well-planned way to create a scene; it is a strategy used by professionals that makes scene creation straightforward. Beginners, on the other hand, tend to dive in headfirst and work on the most detailed objects first. This is a daunting way to work, and can quickly lead to frustration and overwhelm. Remember, sketch first, then refine.
Likewise, when creating an organic model, beginners tend to start with the most detailed areas first, and flesh out the remaining parts later, a haphazard way to create a character. This may be one reason why box modeling has grown to be so widely popular. A modeler can easily create the complete figure before refining the details, like eyes, lips, and ears.
Perhaps the best strategy is to use a hybrid workflow when creating organic models. A well planned organic model is created using a combination of box modeling and poly modeling. The arms, legs, and torso can be sketched out with box modeling, while the fine details of the head, hands, and feet are poly modeled. This is a compromise professional modelers seek which prevents them from getting bogged down in details. It can make the difference between a completed character, and one that is never fleshed out beyond the head. Beginners would be wise to follow this advice.
Another aspect of proper workflow is creating a model with an ideal 3D mesh topology. Topology optimization is usually associated with creating models used in animation. Models created without topology that flows in a smooth, circular pattern, may not animate correctly, which is why it is important to plan ahead when creating any 3D object that will be used for animation.
The most frequently discussed topology is the proper creation or placement of edgeloops. An edgeloop is a ring of polygons placed in an area where the model may deform, as in the case of animation. These rings of polygons are usually placed around areas where muscles might be, such as in the shoulder or elbow. Edegeloop placement is critical when creating faces. When edgeloops are ignored, models will exhibit “tearing” when animated, and the model will need to be reworked or scrapped altogether in favor of a properly-planned model.
The next step to creating great models is simply to practice and examine the work of artists you admire. Some of the best 3D modelers are also fantastic pencil-and-paper artists. It will be well worth your time to practice drawing, whether you’re a character creator or a wanna-be architect. Good modeling requires a lot of dedication. You’ll need to thoroughly understand the software you’re using, and the principles of good 3D model creation laid out above. Character artists will need to learn proportion and anatomy.
By understanding these basics of modeling you’ll save yourself a lot of frustration and discouragement, and you’ll be well on your way to becoming a prolific 3D artist.
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Is there such a thing as too much money?
by Fred E. Foldvary, Senior EditorWhat is inflation? There are two economic meanings of inflation. The first meaning is monetary inflation, having to do with the money supply. To understand that, we need to understand that the impact of money on the economy depends not just on the amount of money but also on its rate of turnover.
We all know that money circulates. How fast it circulates is called its velocity. For example, suppose you get paid $4000 every four weeks. You are circulating $4000 13 times per year. Then suppose you instead get paid $1000 each week. Your total spending is the same, but now you are circulating $1000 52 times per year. The velocity of the money is 52, but the money you hold has been reduced to one fourth its previous amount, although the money held times the velocity is the same. The effect on the economy is the money supply times the velocity.
Monetary inflation is an increase in the money supply, times the velocity, which is greater than the increase in the amount of transactions measured in constant dollars. Simply put, if velocity does not change, monetary inflation is an increase in money that is greater than the increase in goods.
Price inflation is an on-going increase in the price level. The level of prices is measured by a price index, such as the consumer price index (CPI). Usually, price inflation is caused by monetary inflation. So let’s take a look at recent monetary inflation.
The broadest measure of money is MZM, which stands for money zero maturity, funds which can be readily spent. The Federal Reserve Bank of St. Louis keeps track of various measurements of money. Its data show that on an annual basis, MZM increased by 13 percent in January 2008, 36 percent in February, and 23 percent in March. These are huge increases, since gross domestic product, the total production of goods, increased at an annual rate of only .6 percent during these months. In 2006, MZM grew at an annual rate of only 4 percent.
High monetary inflation results in high price inflation. Indeed, in May 2008 the consumer price index rose by 4.2 percent from the level of May 2007. For the month, the increase for May was .6 percent, an annual rate of 7.2 percent. The “Consumer Price Index for All Urban Consumers” (CPI-U) increased 0.8 percent in May, before seasonal adjustment, for an annualized increase of 9.6 percent. The “Consumer Price Index for Urban Wage Earners and Clerical Workers” (CPI-W) increased 1.0 percent in May, prior to seasonal adjustment, for a whopping annual increase of 12 percent.
The rapid rise in oil prices fueled the increase in the price of gasoline, while the greater demand for grains made food prices rise, but beneath these rises is the monetary inflation that creates a higher demand for goods in general. The government reports that “core inflation,” not counting gasoline and food, is lower, but what counts for people is everything they buy, including food and fuel. If you have to pay much more for food and gasoline, there is less money for other things, so of course these will not rise in price as much.
In making monetary policy, the Federal Reserve targets the federal funds interest rate, which banks pay when they borrow funds from one another. During the financial troubles during the first few months of 2008, the Fed aggressively lowered the federal funds rate to 2 percent and also indicated that it would supply limitless credit to banks that borrowed directly from the Federal Reserve.
The Fed lowers the interest rate by increasing the supply of money that banks have to lend; to unload it, banks charge borrowers less interest. To start, the Fed buys U.S. Treasury bonds from the public. The Fed pays for the bonds not by using old money it has lying around but by increasing the reserves held by the banks in their accounts at their local Federal Reserve Bank then using that new money.
This increase in reserves or bank funds is a creation of money out of nothing. Actually, this does not violate the law of conservation, because this creation of money is at the expense of the value of all other money holdings. Every extra dollar created by the Fed decreases the value of the dollars you hold by a tiny amount.
Most monetary reformers stop there, but that is not enough. The current financial instability is also caused by the real estate boom-bust cycle, since even with sound money, an economic expansion would spark a speculative boom in land values. In a competitive market, when produced goods rise in price, producers usually supply more, bringing the price back down or limiting the rise. But land is not produced, so with increased demand, the price has nowhere to go but up. Speculators drive the price of land based on expectations of even higher future prices, but at the peak of the boom, the price becomes too high for those who want to use the land.
Real estate stops rising and then falls, and that brings the financial system down with it, as we have witnessed during the past year. To prevent the inflation in land prices, we need to remove the subsidy, the pumping up of land value from the civic benefits paid by returns on labor and capital goods. We can remove the land subsidy by tapping the land value or land rent for public revenue. Land-value tapping or taxation plus free-market money and banking would provide price and financial stability.
Only the free market can know the right money supply. Some people think the government could just print money and spend it. That is what is happening in Zimbabwe, which has an inflation rate of one hundred thousand percent. Much of the population has fled the country. Once government can create money at will, there is really no way to limit it, and if there is some limiting rule, then the money supply becomes too rigid. Only free market competition and production can combine price stability with money-supply flexibility.
-- Fred Foldvary
Copyright 2008 by Fred E. Foldvary. All rights reserved. No part of this material may be reproduced or transmitted in any form or by any means, electronic or mechanical, which includes but is not limited to facsimile transmission, photocopying, recording, rekeying, or using any information storage or retrieval system, without giving full credit to Fred Foldvary and The Progress Report.
Part III, The Trouble With Money and its Cure
A Better Way to Pay for Railways?
How Economic Systems Really Work
Email this article Sign up for free Progress Report updates via email
What are your views? Share your opinions with The Progress Report:
Page One Page Two Archive Discussion Room Letters What's Geoism?
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Indian removal had been taking place in the United States since the 18th Century as more Americans made the move westward. In the early 19th Century, Andrew Jackson and the majority of white Americans like him, wanted the Indians to move west of the Mississippi, out of the way from white expansion. Popular thought was that the Indians were savages who could not be civilized, and integration with the white culture was not a possibility.
Through the next several years, Indian tribes all over the eastern front were forced to reservations of proportional inequality compared with land once owned. The United States bought the land from the Indians while using its brute power to force unruly tribes west. No matter how much they tried, the Indians were no match for the strength of the United States.
Indians of the Sauk and Fox tribes tried to take back land that was ceded to the United States wrongfully. When they inhabited the vacant land, Americans saw them as a threat to the white settlements close-by. Illinois state militia was sent in to destroy the so-called "invaders." The Indians retreated back and the militia continued to attack until most had been killed.
Were Americans justified in the mass movement of Indian tribes? I would have to say they were not. I cannot see the logic in their assumptions of the Indians. For the most part, little interaction took place with the Indians. Yet, Americans still believed they were uncivilized.
Perhaps the problem was in terms of envy. Indians had been capable of adapting to land and using the land efficiently for years at a time. I think Americans saw how the Indians were able to do this, and became jealous of their superior farming abilities. Land was becoming useless in the east, and Indians had been able to use their land repeatedly. Americans saw this fertile land as rich in potential profit and were willing to go to any length in acquiring it.
Evidence of the two cultures working together in a society was apparent in New Mexico, Texas, and California. If these people were able to survive and live off each other, I would have to assume that had the United States made an effort, they could have resolved this situation in an easier manner. Unless it was jealousy that was driving them to take the Indian land. Something tells me it was exactly that which caused such a debacle. Superior in farming techniques and land use, the Indians efficient ways were the downfall of their land availability.
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There are many techniques available to help students get started with a
piece of writing. Getting started can be hard for all levels of writers.
Freewriting is one great technique to build fluency. That was
explored in an earlier lesson plan: http://www.thirteen.org/edonline/adulted/lessons/lesson18.html
This unit offers some other techniques. These techniques may be especially
helpful with students who prefer a style of learning or teaching that could
be described as visual, spatial, or graphic. Sometimes those styles or overlooked
in favor of approaches that are very linguistic or linear. The approaches
here will attend to a broader range of learning styles as they add variety.
- Writing: Writing Process, Pre-Writing, Autobiography, Exposition,
Personal Narrative, Argumentation, Comparison and Contrast, Description.
Students will be able to:
- Write more fluently (writing more with greater ease)
- Generate writing topics
- Select topics that will yield strong pieces of writing
- Connect personal experience, knowledge, and examples to an assigned
- Produce better organized pieces of writing
National Reporting System of Adult Education standards are applicable here.
These are the standards required by the 1998 Workforce Investment Act. See
Pencils, colored pencils, pens, markers, crayons, unlined paper, magazines
and newspapers with pictures inside, glue or paste, and paper. Big paper
or poster board can make the pre-writing exercises more eye-catching,
more of a project, and better for display.
Video and TV:
Prep for Teachers
Make sure you try each of the activities yourself before you ask students
to do them. That will give you a better understanding of the activities
and help you recognize any potential points that may be confusing or difficult.
This also gives you a sample to show the students. Its much easier
to create a diagram if you are shown an example of one.
Here are some Web sites that give background and even more ideas about you
pre-writing, diagrams, graphic organizers, and other ideas to get started
with writing. There is some repetition here. You dont have to read
them all. But check them out and see what you think.
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No one knows how the first organisms or even the first organic precursors formed on Earth, but one theory is that they didn't. Rather, they were imported from space. Scientists have been finding what looks like biological raw material in meteorites for years, but it's usually been shown to be ground contamination. This year, however, investigators studying a dozen meteorites that landed in Antarctica found traces of adenine and guanine two of the four nucleobases that make DNA. That's not a big surprise, since nucleobases have been found in meteorites before. But these were found in the company of other molecules that were similar in structure but not identical. Those had never been detected in previous meteorite samples and they were also not found on the ground where the space rocks landed. That rules out contamination and rules in space organics. A little adenine and guanine in the company of other mysterious stuff is a long, long way from something living but it's closer than we were before.
Next Star Wars Gets Real
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Given all the evidence presently available, we believe it entirely reasonable that Mars is inhabited with living organisms and that life independently originated there
The conclusion of a study by the National Academy of Sciences in March 1965, after 88 years of surveying the red planet through blurry telescopes. Four months later, NASA’s Mariner 4 spacecraft would beam back the first satellite images of Mars confirming the opposite.
After Earth and Mars were born four and a half billion years ago, they both contained all the elements necessary for life. After initially having surface water and an atmosphere, scientists now believe Mars lost it’s atmosphere four billion years ago, with Earth getting an oxygenated atmosphere around half a billion years later.
According to the chief scientist on NASA’s Curiosity mission, if life ever existed on Mars it was most likely microscopic and lived more than three and a half billion years ago. But even on Earth, fossils that old are vanishingly rare. “You can count them on one hand,” he says. “Five locations. You can waste time looking at hundreds of thousands of rocks and not find anything.”
The impact of a 40kg meteor on the Moon on March 17 was bright enough to see from Earth without a telescope, according to NASA, who captured the impact through a Moon-monitoring telescope.
Now NASA’s Lunar Reconnaissance Orbiter will try and search out the impact crater, which could be up to 20 metres wide.
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As the years tick by with most of the planet doing little in the way of reducing carbon emissions, researchers are getting increasingly serious about the possibility of carbon sequestration. If it looks like we're going to be burning coal for decades, carbon sequestration offers us the best chance of limiting its impact on climate change and ocean acidification. A paper that will appear in today's PNAS describes a fantastic resource for carbon sequestration that happens to be located right next to many of the US' major urban centers on the East Coast.
Assuming that capturing the carbon dioxide is financially and energetically feasible, the big concern becomes where to put it so that it will stay out of the atmosphere for centuries. There appear to be two main schools of thought here. One is that areas that hold large deposits of natural gas should be able to trap other gasses for the long term. The one concern here is that, unlike natural gas, CO2 readily dissolves in water, and may escape via groundwater that flows through these features. The alternative approach turns that problem into a virtue: dissolved CO2 can react with minerals in rocks called basalts (the product of major volcanic activity), forming insoluble carbonate minerals. This should provide an irreversible chemical sequestration.
The new paper helpfully points out that if we're looking for basalts, the East Coast of the US, home to many of its major urban centers and their associated carbon emissions, has an embarrassment of riches. The rifting that broke up the supercontinent called Pangea and formed the Atlantic Ocean's basin triggered some massive basalt flows at the time, which are now part of the Central Atlantic Magmatic Province, or CAMP. The authors estimate that prior to some erosion, CAMP had the equivalent of the largest basalt flows we're currently aware of, the Siberian and Deccan Traps.
Some of this basalt is on land—anyone in northern Manhattan can look across the Hudson River and see it in the sheer cliffs of the Palisades. But much, much more of it is off the coast under the Atlantic Ocean. The authors provide some evidence in the form of drill cores and seismic readings that indicate there are large basalt deposits in basins offshore of New Jersey and New York, extending up to southern New England.
These areas are now covered with millions of years of sediment, which should provide a largely impermeable barrier that will trap any gas injected into the basalt for many years. The deposits should also have reached equilibrium with the seawater above, which will provide the water necessary for the chemical reactions that precipitate out carbonate minerals.
Using a drill core from an onshore deposit, the authors show that the basalt deposits are also composed of many distinct flows of material. Each of these flows would have undergone rapid cooling on both its upper and lower surface, which fragmented the rock. The core samples show porosity levels between 10 and 20 percent, which should allow any CO2 pumped into the deposits to spread widely.
The authors estimate that New Jersey's Sandy Hook basin, a relatively small deposit, is sufficient to house 40 years' worth of emissions from coal plants that produce 4GW of electricity. And the Sandy Hook basin is dwarfed by one that lies off the Carolinas and Georgia. They estimate that the South Georgia Rift basin covers roughly 40,000 square kilometers.
The authors argue that although laboratory simulations suggest the basic idea of using basalts for carbon sequestration is sound, the actual effectiveness in a given region can depend on local quirks of geology, so pilot tests in the field are absolutely essential for determining whether a given deposit is suitable. So far, only one small-scale test has been performed on any of the CAMP deposits.
Given the area's proximity to significant sources of CO2 and the infrastructure that could be brought into play if full-scale sequestration is attempted, it seems like one of the most promising proposals to date.
PNAS, 2010. DOI: 10.1073/pnas.0913721107
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Chandra "Hears" a Supermassive Black Hole in Perseus
A 53-hour Chandra observation of the central region of the Perseus galaxy cluster (left) has revealed wavelike features (right) that appear to be sound waves. The features were discovered by using a special image-processing technique to bring out subtle changes in brightness.
These sound waves are thought to have been produced by explosive events occurring around a supermassive black hole (bright white spot) in Perseus A, the huge galaxy at the center of the cluster. The pitch of the sound waves translates into the note of B flat, 57 octaves below middle-C. This frequency is over a million billion times deeper than the limits of human hearing, so the sound is much too deep to be heard.
The image also shows two vast, bubble-shaped cavities, each about 50 thousand light years wide, extending away from the central supermassive black hole. These cavities, which are bright sources of radio waves, are not really empty, but filled with high-energy particles and magnetic fields. They push the hot X-ray emitting gas aside, creating sound waves that sweep across hundreds of thousands of light years.
The detection of intergalactic sound waves may solve the long-standing mystery of why the hot gas in the central regions of the Perseus cluster has not cooled over the past ten billion years to form trillions of stars. As sounds waves move through gas, they are eventually absorbed and their energy is converted to heat. In this way, the sound waves from the supermassive black hole in Perseus A could keep the cluster gas hot.
The explosive activity occurring around the supermassive black hole is probably caused by large amounts of gas falling into it, perhaps from smaller galaxies that are being cannibalized by Perseus A. The dark blobs in the central region of the Chandra image may be fragments of such a doomed galaxy.
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SL Psychology/Intro to Research Methods
The following items should be included in this section: The Hypothetico-deductive (scientific)method, types of psychological research methods, research designs, sampling, reliability, validity, and triangulation.
Research into mind can be traced back to Ancient Greece. However, empirical psychological research has its roots in investigations into cognitive functions such as introspection and memory. While early psychological researchers attempted to bring the same standards of rigor and control to their investigations as physical scientists enjoy, psychological research poses unique obstacles. Psychological research investigates mind. Only recently the contents of the mind become observable since the advent of neuro-imaging technologies such as EEGs, PET scans, and fMRIs, thus early psychological research was focused on disagreements between different schools or generations of researchers that used varied approaches toward their investigations into the invisible mind. For example, cognitive researchers rely on inferences made from activities aimed at employing cognitive functions such as memory as opposed to examining how or where actual memories are laid down. Conversely Behaviorist researchers employed a more empirically rigorous method seeking only to make generalizations about phenomena that were directly observable and replicable in controlled settings.
Contemporary psychological research is derived from these disparate traditions and perspectives. It utilizes the hypothetico-deductive or scientific method:
1. observation and data gathering
2. inference of generalizations
3. construction of explanatory theories
4. deduction of hypothesis to test theories
5. hypothesis testing
6. support or challenges to existing theories and commensurate adjustments.
Theories and Hypothesis
Two key steps, theory construction and hypothesis deduction/testing pose special problems for researchers. Theories are sets of related generalizations explaining a specific mental phenomena e.g. schema and memory organization and hypotheses are specific predictions for research investigations. These steps are derived from empirical data, but are heavily influenced by an individual researcher’s perspective. Thus, researchers seek to clearly articulate operational definitions in an effort to make their research easily replicable. Additionally, controls are implemented to ensure credibility of results and subsequent conclusions. Finally, published research contributing to knowledge in the discipline is peer reviewed and usually rigorously scrutinized. Psychological research can take many forms ranging from: controlled laboratory true experiments (involving the manipulation of independent variables and controls for confounding variables) to field research (involving deliberate manipulation of independent variables in natural uncontrolled environments) to naturalistic/quasi experimental method (involving observation and analysis of independent variables changed by natural incidence). No matter which research method is employed, controls are carefully implemented to ensure the credibility of research. Key issues surrounding controls are: research design, sampling, reliability and validity.
The underlying structure of an investigation. It involves how psychologists use subjects/participants in their experiments. The three most common designs are:
1.Repeated Measures: using the same subjects in the experimental and control conditions
2.Independent Measures :using different subjects/participants in the experimental and control conditions
3. Matched Pairs :using different subjects/participants in the experimental and control conditions with each sample having similar characteristics.
The process of selecting participants/subjects to examine derived from a target population (a specified subpopulation of all humans). The results of a study are inferred from examination of the sample’s performance on a given measure, thus the sample is key in the line of reasoning from initial design to examination of results. Several methods can be employed when choosing a sample: random, stratified and convenience. Random sampling provides the best chance for the sample group to be representative of the target population. Stratified samples reflect similar proportions of various sub-groups within a sample. Convenience sampling involves choosing participants/subjects that are available at the time of data collection. Convenience samples do not control for possible biases that may within certain subgroups of a population and thus the results and conclusions from a convenience sample must be analyzed with caution and triangulated.
A study is reliable if it is replicable and the same results are achieved repeatedly. There are four types of reliability in regard to psychological study:
- Test-Retest Reliability (also called stability reliability)
- Interrater Reliability
- Parallel Forms Reliability
- Internal Consistency Reliability
To judge for reliability in this case, the test is administered two different times to the exact same or similar subjects. This judges for consistency of results across time, and to make sure the results were not affected by context of the time. Reliability is higher if the retest is close in chronological proximity to the original test.
Research psychologists tend to replicate older studies to generate theories or to amend findings to account for reliability. In attention for example, Treisman consistently retested findings to amend the attention models.
Two or more judges score the test. The scores are then compared to determine how much the two raters agree on the consistency on a rating system.
An example of interrater reliability would be that of teachers grading essays for an AP or IB exam. If a scale from 1 to 5 was used (where 1 is the worst and 5 is the best), and one teacher gave an essay a score of 2 and another gave a score of 5, then the reliability would be inconsistent. Through training, practice, and discussion, the individual raters can reach a consistent level of assessing an experiment, test, or result. Often, the raters are moderated by a higher rater who will assist in reaching consistency.
Parallel Forms Reliability
A large set of questions that are related to the same construct are generated and then divided into two sets. The two different sets are given to the same sample of people at the same time. Therefore, the two tests that study the same content are judged against each other for consistency.
An example would be a pretest-posttest, where the two groups would either receive form 1 or form 2, and in the posttest situation, the groups would be switched.
Internal Consistency Reliability
In this case, the tool is used as the tool to determine reliability. Thus would be a test situation in which the items on the test measure the same content. Often, questions can be strikingly similar, which shows that the test is also a measure for internal consistency reliability. Therefore, the similar questions should be answered in the same way. There are different ways to measure internal consistency reliability:
- Average Inter-item Correlation
- Average Itemtotal Correlation
- Split-Half Reliability
- Cronbach's Alpha (a)
Quantitative versus Qualitative Measures
Coolican, H. (2004). Research methods and statistics in Psychology. Cambridge University Press.
1. In what ways has new technology changed the science of psychology? Provide three examples.
2. How does the importance of validity and reliability change depending on the type of study?
3. In what ways will the different aspects of an experiment (sampling, methods, reliabilty, and validity) affect the results and conclusions of an psychology study?
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The Farmers Alliance
The populist movement first came into being in small communities far from any cities or centers of political or cultural activity. During the summer of 1890 farm families in the agrarian South and West gathered in their respective areas to discuss their problems. At these gatherings, agrarian families listened to the speeches of recruiters from the “National Farmers’ Alliance.” The Farmers’ Alliance grew at an astounding speed.
During the late 1800’s discontent among the agrarian population was becoming a worldwide issue. With the advent of advanced forms of transportation and communication the farmers were suddenly hurled into a far larger market that they no longer were in control of. Due to the increased opportunity for competition, prices of crops began to drop. However, this same phenomenon affected other products as well and, although farmers were making less profit quantitatively, their actual purchasing power (or qualitative profit) was increasing. Farmers expressed grievances about the cost of shipping their goods, however during this period the price of shipping actually decreased. All of these things, however, were still detrimental to the agrarian community because, up until this point, they had not required the services of the railroad to ship crops, and they had not been in need of as many manufactured goods to support their farms.
All of this can be deceiving. While general economic trends were more positive than anything else, the situation of farming communities varied widely from location to location. In fact, no nationwide patters could be clearly defined. In reality there was a more pressing issue that lead to the ascension of the populist movement: Despite overwhelming evidence to the contrary, farmers were having the distinct feeling that their situation was becoming worse. It is said that reality is perception, and this is certainly true in any social science because people do not react to their environment, they react to their perception of their environment. The farmers perceived doomsday. In the 1870’s and 80’s there was a growing social trend favoring cities and industry. Farmers’ children were leaving their homes and family businesses to make it big in the city. Literature was published during this time describing the drab and meaningless existence of farm life.
During this time multitudes of farmers' organizations were changing and merging with each other. Two major organizations emerged, both calling themselves the Farmers’ Alliance: The Northwestern Alliance in Mississippi and the West, and the Southern Alliance (however, the geographical coverage of these two organizations is not highly clear-cut). The Southern Alliance was started in Texas in 1875 and began absorbing other agrarian societies after 1886. The primary concerns of this society were residual systems from the old Civil War South. The sharecropping system, crop-liens, and overworked land ranked at the top of their lists. The Northwestern Alliance was similar to the Southern alliance, but differed on policies of the Southern alliance such as secrecy, and segregated organizations for Blacks. In 1889 the Southern alliance took on the “National Farmers’ Alliance” title and absorbed the greater part of the Northwestern alliance. The Alliance then formed its own political party due to a disapproval of both the Republican and Democratic parties. The first Peoples’ Party was formed in 1890. The party’s demands were for a federal farmers reserve (the sub-treasury) that would allow crops to be temporarily sold to the government, which would then hold them until the most opportune selling time presented itself, then distribute the profits back to the farmers. They also demanded, and much more within reason, the free coinage of both gold and silver, an abolition on tariffs, a federal income tax, the direct election of senators, and railroad regulation. During the elections of 1890 the fledgling people’s party gained thirty-eight supporters in congress.
The sub-treasury was a system devised by the populists to combat what they perceived to be a bad market for their products. It would allow farmers to store their crops in government warehouses and then take out a government loan for up to 80% of the market price of said goods. The loan would come to term upon the sale of the crops, which could be held until ideal market conditions presented themselves. This is an ingenious idea, except that it is basically asking for government aid for farmers and therefore it was slightly harder to gain acceptance at the national level than it was to convince their neighbors that it was a good idea.
The Federal Income Tax
Why would a farmer who is struggling to keep their home ask for a new tax? Well, boys and girls, is it simple. How does the government make money? Collecting taxes. How did the government make their money at this time? Property taxes. Who had the most money? Factory owners and businessmen did. Who had the most land? Farmers. Who paid the most money? Farmers. Is this fair?.
The Election of 1892
After the 1890 elections the populists formed the political party that gave them their name, the new People’s party was also known as the Populist Party. Up until this time the Populists had been participating with the Democratic Party to avoid splitting the white vote by forming a new party, and thus neutering the White’s Supremacy. The new party was formed because the Populists were not content with the false support provided to them by their democratic congressmen. The Democrats played off of the popularity of the populist movement, but rarely followed through on their campaign promises. The new Populist Party gained over one million votes in the election of 1892 and gained 22 electoral votes. Populist governors were installed in Kansas and North Dakota, and ten congressmen, five senators, and approximately fifteen hundred state legislators were installed. The populists never ran a more successful election, but the Democrats, through coercion, fraud, and manipulation, suppressed the populists’ following during the election of 1892.
Push for Equality
There was one unintended side effect of the populist movement. In the South, where racism was most rampant, there were certain populist politicians who saw a definite similarity of condition between white and black farmers. Both were in the same bad situation. Blacks and Whites served together on populist election committees, spoke from the same platforms, and even served on the same juries. It was unheard of for a black to be called for jury duty at this time. In 1892 a black populist was threatened with a lynching. Two thousand white populist farmers gathered in the area and protected him. Some of these farmers rode all night to get there. The populist sheared across race lines in many ways.
Then there was The Panic of 1893.
Primary Source: "America Past and Present" by Divine, and Lecture from Mr. Gruver's American History Class.
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Mario Schenberg, Brazil’s most important theoretical physicist, who researched the formation of supernova stars, was born in Recife on this date in 1914. In the 1940s, together with Indian physicist and Nobel laureate Subrahmanyan Chanrasekhar, he discovered the Schenberg-Chandrasekhar limit, which is the maximum mass of the core of a star prior to its gravitational collapse. Schenberg also made significant contributions to mathematics vis-a-vis quantum physics, and was widely respected as a writer and art critic. He was twice elected to be Sao Paolo state legislator on the Communist ticket; following Brazil’s 1964 military coup d’etat, he was forced into retirement by presidential decree and was jailed for several months (his second jailing for communist activism). He also received death threats from Brazilian neo-Nazis for his opposition to a joint Brazil-Germany plan to build nuclear power stations in Brazil in 1975. Schenberg died in 1990. To view a video about the “Mario Schenberg Space Ship,” an interactive educational program for kids at the University of Sao Paolo, click here.
“The energy disappears in the nucleus of the supernova as quickly as . . . money disappeared at that roulette table.”—Mario Schenberg
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Sickle cell disease. It's a strange sounding name — and, no, the word "sickle" isn't related to "sick." The disease got this name because it causes blood cells to be curved or C-shaped, like the shape of an old-fashioned farm tool called a sickle.
Normally, blood cells are round and look a bit like donuts. In people with sickle cell disease, some of the red blood cells harden and curve. They also break down faster than healthy red blood cells and can clog a person's small blood vessels.
Sickle cell disease is inherited. You can't catch it from someone. It's most common among people of African or Hispanic descent, but it can occur in many different ethnic groups.
There's no easy cure for sickle cell disease. In rare cases, it is possible to get sick enough to die, but most teens and kids are able to manage sickle cell disease by eating carefully and taking vitamins (especially folic acid), getting enough rest, and scheduling regular visits to the doctor — and by having supportive friends like you who let them just be themselves!
What's My Friend Going Through?
Your friend may be tired more often than you are or have trouble fighting infections. People with sickle cell disease can develop . They also may have some .
Your friend also might have bouts of severe pain, caused by the red blood cells restricting blood flow. These are called "pain crises" and they can happen anywhere in the body. Pain crises can last anywhere from a few moments to several days or even longer. Right now, there's no cure, but doctors can give a person medications to help lessen the pain.
If you want to know what it's like to have sickle cell disease, ask your friend: Your gentle curiosity may help your friend feel less self-conscious or less embarrassed (after all, we all can feel awkward about the things that make us feel different from our friends). If your friend doesn't feel like talking, though, don't press. Doing a little research online can help you get a sense of what it's like to live with sickle cell disease.
Most teens with sickle cell disease have to pay extra attention to diet, exercise, and watching how their bodies respond to common infections. Some may take antibiotics to help fight off common bacteria. They might need to have frequent doctor's appointments to stay well.
First, be there for your friend. OK, so this is obvious. But sometimes a friend may not realize how important it can be. People with chronic illnesses often feel isolated and alone, especially if their symptoms keep them out of school for stretches of time.
Visit your friend as often as you can. Even if you aren't sure what to say, just being there to listen to music, share some quiet time together, and show your support will mean a lot.
If you can't be there in person, take a moment to text, call, or IM. Set up a social network group so your friend can stay connected to a bunch of people. Or surprise your friend by sending a card or note through the mail.
Talk about it — and listen. Most of us like to talk with people we love and trust when we're going through tough times. Listen, ask questions, and do some basic research on your own so you can understand more about the condition and what your friend might be feeling. Don't be afraid to ask questions of your friend's family, the doctors, and other people with sickle cell disease.
Your friend might have to limit some of activities, especially sports, and may feel self-conscious about having sickle cell disease. Try to be understanding and remind your friend of the skills that make him or her shine — like a great singing voice or debating skills. Having a chronic illness is only a part of who your friend is.
Encourage healthy habits. Eating well and staying hydrated is important for all of us, but it's especially important for someone with sickle cell disease. Help your friend avoid alcohol and smoking, both of which can aggravate the condition. It's a huge help to a friend (not to mention your own health!) when you don't drink or smoke, since people who feel like they're "different" may think they have to drink or smoke in order to fit in.
Know the warning signs. Talk to your friend if you notice any of these symptoms. They may be signs of a serious problem:
severe chest pain
shortness of breath (difficulty breathing)
abdominal swelling or pain
any sudden weakness or loss of feeling, slurring of speech
sudden changes in vision
Sickle cell disease carries a (small) risk of , so it's a good idea to know the signs so your friend can get medical attention if he or she needs it. But don't panic, and don't let watching for danger signs get in the way of having fun together. Most problems won't be serious.
Be the go-to person. Managing a chronic disease takes a lot of energy and your friend may tire more easily than you do. If your friend has to miss school or starts to fall behind, nominate yourself to be the point person in charge of bringing books and assignments, and keeping him or her up to date on what classmates and friends are doing.
Take care of yourself. When a close friend has a disease like sickle cell, it can take a toll on you, too. So try to be aware of your own emotional needs. It's particularly hard to watch someone you care about endure a pain crisis — it can feel helpless and scary. Think about how you want to respond and talk to your friend about what's most helpful. Talk with a trusted adult about the impact this has on you, or keep a journal or write poetry or songs to get your feelings out.
It can feel good to be there for your friend, in whatever way feels natural, so that the disease doesn't take center stage. More than anything, just focus on having fun together.
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|U.S. Naval Observatory||Earth Orientation Department|
In 1956, following several years of work, two astronomers at the U. S. Naval Observatory (USNO) and two astronomers at the National Physical Laboratory (Teddington, England) determined the relationship between the frequency of the Cesium atom (the standard of time) and the rotation of the Earth at a particular epoch. As a result, they defined the second of atomic time as the length of time required for 9 192 631 770 cycles of the Cesium atom at zero magnetic field. The second thus defined was equivalent to the second defined by the fraction 1 / 31 556 925.9747 of the year 1900. The atomic second was set equal, then, to an average second of Earth rotation time near the end of the 19th century.
The Rapid Service/Prediction Center of the International Earth Rotation Service (IERS), located at the U.S. Naval Observatory, monitors the Earth's rotation. Part of its mission involves the determination of a time scale based on the current rate of the rotation of the Earth. UT1 is the non-uniform time based on the Earth's rotation.
The Earth is constantly undergoing a deceleration caused by the braking action of the ocean tides. Through the use of ancient observations of eclipses, it is possible to determine the deceleration of the Earth to be roughly 2 milliseconds per day per century. This is an effect which causes the Earth's rotational time to slow with respect to the atomic clock time. Since it has been about 1 century since the defining epoch (i.e., the duration since 1900), the difference has accumulated to roughly 2 milliseconds per day. Other factors also affect the Earth's dynamics, some in unpredictable ways, so that it is necessary to monitor the Earth's rotation continuously.
In order to keep the cumulative difference in UT1-UTC less than 0.9 seconds, a leap second is inserted periodically in the atomic UTC time scale to decrease the difference between the two. This leap second can be either positive or negative depending on the Earth's rotation. Since the first leap second in 1972, all leap seconds have been positive (click here for a list of all announced leap seconds). This reflects the general slowing trend of the Earth due to tidal braking.
Confusion sometimes arises over the misconception that the occasional insertion of leap seconds every few years indicates that the Earth should stop rotating within a few millennia. The confusion arises because some mistake leap seconds as a measure of the rate at which the Earth is slowing. The one-second increments are, however, indications of the accumulated difference in time between the two systems. As an example, the situation is similar to what would happen if a person owned a watch that lost two seconds per day. If it were set to a perfect clock today, the watch would be found to be slow by two seconds tomorrow. At the end of a month, the watch will be roughly a minute in error (thirty days of the two second error accumulated each day). The person would then find it convenient to reset the watch by one minute to have the correct time again.
This scenario is analogous to that encountered with the leap second. The difference is that instead of resetting the clock that is running slow, we choose to adjust the clock that is keeping a uniform, precise time. The reason for this is that we can change the time of an atomic clock while it is not possible to alter the Earth's rotational speed to match the atomic clocks. Currently the Earth runs slow at roughly 2 milliseconds per day. After 500 days, the difference between the Earth rotation time and the atomic time would be one second. Instead of allowing this to happen a leap second is inserted to bring the two times closer together.
The decision of when to introduce a leap second in UTC is the responsibility of the International Earth Rotation Service (IERS). According to international agreements, first preference is given to the opportunities at the end of December and June, and second preference to those at the end of March and September. Since the system was introduced in 1972, only dates in June and December have been used.
The official United States time is determined by the Master Clock at the U. S. Naval Observatory (USNO). The Observatory is charged with the responsibility for precise time determination and management of time dissemination. Modern electronic systems, such as electronic navigation or communication systems, depend increasingly on precise time and time interval (PTTI). Examples are the ground-based LORAN-C navigation system and the satellite-based Global Positioning System (GPS). Navigation systems are the most critical application for precise time. GPS, in particular, is widely used for navigating ships, planes, missiles, trucks, and cars anywhere on Earth. These systems are all based on the travel time of electromagnetic signals: an accuracy of 10 nanoseconds (10 one-billionths of a second) corresponds to a position accuracy of about 3 meters (or 10 feet).
Precise time measurements are needed for the synchronization of clocks at two or more sites. Such synchronization is necessary, for example, for high-speed communications systems. Power companies use precise time to control power distribution grids and reduce power loss. Radio and television stations require precise time (the time of day) and precise frequencies in order to broadcast their transmissions. Many programs are transmitted from coast to coast to affiliate stations around the country. Without precise timing the stations would not be able to synchronize the transmission of these programs to local audiences. All of these systems are referenced to the USNO Master Clock.
Very precise time is kept by using atomic clocks. The principle of operation of the atomic clock is based on measuring the microwave resonance frequency (9,192,631,770 cycles per seconds) of the cesium atom. At the Observatory, the atomic time scale (AT) is determined by averaging 60 to 70 atomic clocks placed in separate, environmentally controlled vaults. Atomic Time is a very uniform measure of time (one tenth of one billionth of a second per day).
The USNO must maintain and continually improve its clock system so that it can stay one step ahead of the demands made on its accuracy, stability and reliability. The present Master Clock of the USNO is based on a system of some 60 independently operating cesium atomic clocks and 7 to 10 hydrogen maser atomic clocks. These clocks are distributed over 20 environmentally controlled clock vaults, to ensure their stability. By automatic inter-comparison of all clocks every 100 seconds, a time scale is computed which is not only reliable but also extremely stable. Its rate does not change by more than about 100 picoseconds (.0000000001 seconds) per day from day to day.
On the basis of this computed time scale, a clock reference system is steered to produce clock signals which serve as the USNO Master Clock. The clock reference system is driven by a hydrogen maser atomic clock. Hydrogen masers are extremely stable clocks over short time periods (less than one week). They provide the stability and reliability needed to maintain the accuracy of the Master Clock System.
Very Long Baseline Interferometry (VLBI) is used to determine Universal Time (UT1) based on the rotation of the Earth about its axis. VLBI is an advanced astronomical technique of observing extra-galactic sources (typically quasars) with radio telescopes. The information gained using VLBI can be used to generate images of the distant radio sources, measure the rotation rate of the Earth, the motions of the Earth in space, or even measure how the tectonic plates where the telescopes are located are moving on the surface of the Earth. Measuring the Earth's rotational motion is critical for navigation. The most accurate navigation systems rely on measurements using satellite systems which are not tied to the Earth's surface. These systems can provide a position accurate to a about a meter (few feet), but the position of the Earth relative to the satellites must also be known to avoid potentially far larger errors.
The U.S. Naval Observatory has been in the forefront of timekeeping since the early 1800s. In 1845, the Observatory offered its first time service to the public: a time ball was dropped at noon. Beginning in 1865 time signals were sent daily by telegraph to Western Union and others. In 1904, a U.S. Navy station broadcast the first worldwide radio time signals based on a clock provided and controlled by the Observatory.
A time of day announcement can be obtained by calling 202-762-1401 locally in the Washington area. For long distance callers the number is 900-410-TIME. The latter number is a commercial service for which the telephone company charges 50 cents for the first minute and 45 cents for each additional minute. Australia, Hong Kong, and Bermuda can also access this service at international direct dialing rates. You can also get time for your computer by calling 202-762-1594. Use 1200 baud, no parity, 8 bit ASCII.
|Last modified: 24 October 2001||Approved by EO Dept. Head, USNO|
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The research, which is featured on the cover of the July 17, 2005 issue of The Journal of Experimental Medicine, focused on the major human pathogen Staphylococcus aureus and the characteristic yellow-orange color for which it is named ("aureus" is Latin for "golden").
Among the deadliest of all disease-causing organisms, "Staph" is the leading cause of human infections in the skin and soft tissues, bones and joints, abscesses and normal heart valves. Staph especially flourishes in the hospital setting, producing bloodstream and surgical wound infections. The spread of antibiotic resistant strains of Staph, referred to as methicillin-resistant Staphylococcus aureus or MRSA, has reached epidemic proportions and poses a major threat to the public health.
The UCSD team proved for the first time that the golden pigment that coats the surface of Staph is not just for decoration; rather, the molecules that give the bacteria its golden hue also help it resist killing by neutrophils, white blood cells with a front line role in immune defense against invading microbes.
Staph's coloration reflects the production of molecules called carotenoids, similar to those present in carrots and other colorful vegetables and fruits. Dietary carotenoids have long been touted for their antioxidant properties with hope that they could slow aging or fight off cancer. The scientists found that pathogenic Staph took advantage of the antioxidant effects of its carotenoid pigment to extend its own life, by inactivating chemicals deployed by neutrophils that are lethal to most bacteria.
The UCSD team u
Contact: Leslie Franz
University of California - San Diego
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The steps by which molecules in the primordial soup came together to form the genetic backbone of life are largely unknown. One approach to finding out is to artificially create basic life functions in the laboratory and consider if such conditions might have been possible in the Earth’s past. Writing in Physical Review Letters, Hubert Krammer and colleagues at the Ludwig Maximilian University of Munich in Germany show they are able to drive the replication of segments of tRNA (transfer ribonucleic acid), the molecule responsible for translating genetic code into the production of specific proteins, using a purely thermal process.
Krammer et al. begin by rapidly cooling a solution of four halves of tRNA from high temperatures to so that the molecules form hairpins—a state where the strand forms a closed loop on itself, except for a snippet of a sequence of bases, called a “toe hold.” It is this toe hold, which, in principle, carries enough information to encode a protein, that the authors try to protect and replicate by using a thermal process to coax the hairpins to open and pair to a complementary strand. When Krammer et al. thermally cycle the solution between and , the energy stored in the hairpin (which prefers it to bind to a complementary pair instead of itself) compensates for the loss of entropy associated with the molecules pairing up with their partners.
This thermally driven process occurs on a relatively fast time scale of about seconds, an important factor since molecules need to replicate faster than they degrade. According to the authors, convection currents in prebiotic liquids could have provided the necessary quenching and thermal cycling. – Jessica Thomas
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When the Manchu ruled China during the Qing Dynasty, certain social strata emerged. Among them were the Banners, mostly Manchu, who as a group were called Banner People.
Manchu women typically wore a one-piece dress that came to be known as the cheongsam. The qipao fitted loosely and hung straight down the body. You can pull on cheongsam of PLUS SIZE DRESSES Under the dynastic laws after 1644, all Han Chinese were forced to wear a queue and dress in Manchurian qipao instead of traditional Han Chinese clothing, under penalty of death. In the following 300 years, the qipao became the adopted clothing of the Chinese (though it cannot be considered as the traditional dress of Chinese, as it was forced upon them), and was eventually tailored to suit the preferences of the population. Such was its popularity that the garment form survived the political turmoil of the 1911 Xinhai Revolution that toppled the Qing Dynasty. Silk is a natural protein fiber, some forms of which can be woven into textiles. The best-known type of silk is obtained from cocoons made by the larvae of the mulberry silkworm Bombyx mori reared in captivity (sericulture). The shimmering appearance for which silk is prized comes from the fibers' triangular prism-like structure which allows silk cloth to refract incoming light at different angles. "Wild silks" are produced by caterpillars other than the mulberry silkworm and can be artificially cultivated. A variety of wild silks have been known and used in China, South Asia, and Europe since early times, but the scale of production was always far smaller than that of cultivated silks. They differ from the domesticated varieties in color and texture, and cocoons gathered in the wild usually have been damaged by the emerging moth before the cocoons are gathered, so the silk thread that makes up the cocoon has been torn into shorter lengths. Commercially reared silkworm pupae are killed by dipping them in boiling water before the adult moths emerge, or by piercing them with a needle, allowing the whole cocoon to be unraveled as one continuous thread. This permits a much stronger cloth to be woven from the silk. Wild silks also tend to be more difficult to dye than silk from the cultivated silkworm. We can PLUS SIZE DRESSES for you
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Light glowing from a "super-Earth" planet beyond our solar system has been detected by Nasa’s Spitzer Telescope.
Until now, scientists have never been able to detect infrared light emanating from 55 Cancri E, a super-hot extrasolar planet twice the size and eight times the mass of our own.
55 Cancri E is one of five exoplanets orbiting a bright star named 55 Cancri in a solar system lying in the constellation of Cancer (The Crab).
Previously, Spitzer and other telescopes were able to study the planet by observing how the light from 55 Cancri changed as the planet passed in front of the star.
In the new study, Spitzer instead measured how much infrared light came from the planet itself – revealing some of the planet’s major features.
At 41-light years from Earth, the giant planet is considered uninhabitable.
The giant planet is tidally locked, so one side always faces the star. The telescope found that the sun-facing side is extremely hot, indicating the planet probably does not have a substantial atmosphere to carry the sun's heat to the unlit side.
[Related content: Amazing Nasa footage shows how the Earth looks from space]
On its sun-facing side, the surface has a temperature of 1,727 Celsius – or 3,140 degrees Fahrenheit – That’s hot enough to melt silver or aluminium.
The new findings are consistent with a previous theory that 55 Cancri E is a water world: A rocky core surrounded by a layer of water in a "supercritical" state where it is both liquid and gas, and topped by a blanket of steam.
Bill Danchi, Spitzer programme scientist at NASA, said: “Spitzer has amazed us yet again. The spacecraft is pioneering the study of atmospheres of distant planets and paving the way for NASA's upcoming James Webb Space Telescope to apply a similar technique on potentially habitable planets.”
Michael Werner, who also works on the Spitzer project, added: “When we conceived of Spitzer more than 40 years ago, exoplanets hadn't even been discovered. Because Spitzer was built very well, it's been able to adapt to this new field and make historic advances such as this.”
The planet was first discovered in 2004 and the new findings are published in the current issue of Astrophysical Journal Letters.
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The Savage Islands, or Ilhas Selvagens in Portuguese, are a small archipelago in the eastern North Atlantic Ocean between the archipelago of Madeira to the north and the Canary Islands to the south. Like these other island groups, the Savage Islands are thought to have been produced by volcanism related to a mantle plume or “hot spot.”
Typically, volcanoes are fueled by magma being generated where tectonic plates are colliding or being pulled apart. The active volcanoes remain at the plate boundaries, even as the plates shift. Mantle plumes, in contrast, are relatively fixed regions of upwelling magma that can feed volcanoes on an overlying tectonic plate. When a tectonic plate passes over the mantle plume, active volcanoes form, but they become dormant as they are carried away from the hot spot on the moving tectonic plate. Over geologic time, this creates a line of older, extinct volcanoes, seamounts, and islands extending from the active volcanoes that are currently over the plume.
These two astronaut photographs illustrate the northern (top) and southern (bottom) Savage Islands. The two views were taken 13 seconds apart from the International Space Station; the geographic center points of the images are separated by about 15 kilometers. Selvagem Grande, with an approximate area of 4 square kilometers, is the largest of the islands. The smaller and more irregularly-shaped Ilhéus do Norte, Ilhéu de Fora, and Selvagem Pequena are visible at the center of the lower image. Spain and Portugal both claim sovereignty over the Savage Islands.
All of the islands of the archipelago are ringed by bright white breaking waves along the fringing beaches. Reefs that surround the Savage Islands make it very difficult to land boats there, and there is no permanent settlement on the islands. The islands serve as nesting sites for several species of seabird including petrels and shearwaters, and they are included on the tentative list of additional UNESCO World Heritage Sites.
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In 1621, the Plymouth colonists and Wampanoag Indians shared an autumn harvest feast that is acknowledged today as one of the first Thanksgiving celebrations in the colonies. For more than two centuries, days of thanksgiving were celebrated by individual colonies and states.
It wasn't until October 1777 that all 13 colonies celebrated day of Thanksgiving.
The very first national day of Thanksgiving was held in 1789, when President George Washington proclaimed Thursday, Nov. 26, to be "a day of public thanksgiving and prayer to be observed by acknowledging with grateful hearts the many signal favors of Almighty God especially by affording them an opportunity peaceably to establish a form of government for their safety and happiness."
Though a national day of Thanksgiving was declared in 1789, Thanksgiving was not an annual celebration.
We owe the modern concept of Thanksgiving to poet and editor, Sarah Josepha Hale. Hale wrote the famous nursery rhyme, "Mary Had a Little Lamb," and was editor of "Godey's Lady's Book." She spent 40 years advocating for a national, annual Thanksgiving holiday.
In the years leading up to the Civil War, she saw the holiday as a way to infuse hope and belief in the nation and the constitution. So, when the United States was torn in half during the Civil War and President Abraham Lincoln was searching for a way to bring the nation together, he discussed the matter with Hale.
On Oct. 3, 1863, Lincoln issued a Thanksgiving Proclamation that declared the last Thursday in November (based on Washington's date) to be a day of "thanksgiving and praise."
For the first time, Thanksgiving became a national, annual holiday with a specific date.
For 75 years after Lincoln issued his Thanksgiving Proclamation, succeeding presidents honored the tradition and annually issued their own Thanksgiving Proclamation, declaring the last Thursday in November as the day of Thanksgiving.
However, in 1939, during the Great Depression, the date of Thanksgiving was scheduled to be Nov. 30.
Retailers complained to President Franklin D. Roosevelt (FDR) that this only left 24 shopping days to Christmas and begged him to push Thanksgiving just one week earlier. It was determined that most people do their Christmas shopping after Thanksgiving and retailers hope that with an extra week of shopping, people would buy more.
When FDR announced his Thanksgiving Proclamation in 1939, he declared the date of Thanksgiving to be Thursday, Nov. 23, the second-to-last Thursday of the month.
The new date for Thanksgiving caused a lot of confusion. Calendars were now incorrect. Schools who had planned vacations and tests now had to reschedule. Thanksgiving had been a big day for football games, as it is today, so the game schedule had to be examined.
Before 1939, governors followed the president in officially proclaiming the same day as Thanksgiving for their state. In 1939, many governors did not agree with FDR's decision to change the date and refused to follow him. The country became split on which Thanksgiving they should observe.
Twenty-three states followed FDR's change. Twenty-three other states disagreed with FDR and kept the traditional date for Thanksgiving. Two states, Colorado and Texas, decided to honor both dates.
This idea of two Thanksgiving days split some families because not everyone had the same day off work.
Did it work?
The answer was no. Businesses reported that the spending was approximately the same but the distribution of the shopping was changed.
For those states who celebrated the earlier Thanksgiving date, the shopping was evenly distributed throughout the season. For those states that kept the traditional date, businesses experienced a bulk of shopping in the last week before Christmas.
In 1940, FDR again announced Thanksgiving to be the second-to-last Thursday of the month. This time, 31 states followed him with the earlier date and 17 kept the traditional date. Confusion over two Thanksgivings continued.
Lincoln established the Thanksgiving holiday to bring the country together, but the confusion over the date change was tearing it apart. On Dec. 26, 1941, Congress passed a law declaring that Thanksgiving would occur every year on the fourth Thursday of November.
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Why does this galaxy have so many big black holes?
No one is sure.
What is sure is that
NGC 922 is a ring galaxy created by the collision of a large and small galaxy about
300 million years ago.
Like a rock thrown into a pond, the
ancient collision sent ripples of
high density gas out from the impact point near the center that partly condensed into stars.
Pictured above is NGC 922 with its beautifully complex ring along the left side, as imaged recently by the
Hubble Space Telescope.
Observations of NGC 922 with the
Chandra X-ray Observatory, however, show several glowing X-ray knots that are likely large black holes.
The high number of massive black holes was
somewhat surprising as the gas composition in
NGC 922 -- rich in heavy elements -- should have discouraged almost anything so massive from forming.
Research is sure to continue.
spans about 75,000 light years, lies about 150 million light years away, and can be seen with a small telescope toward the constellation of the furnace (Fornax).
Acknowledgement: Nick Rose
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Torque is an important factor in much of the equipment on a factory floor. Measuring torque is often something that's misunderstood, which can lead to over- under-designing of measurement systems. This article addresses the many techniques and tradeoff of torque measurement techniques.
Torque can be divided into two major categories, either static or dynamic. The methods used to measure torque can be further divided into two more categories, either reaction or in-line. Understanding the type of torque to be measured, as well as the different types of torque sensors that are available, will have a profound impact on the accuracy of the resulting data, as well as the cost of the measurement.
In a discussion of static vs. dynamic torque, it is often easiest start with an understanding of the difference between a static and dynamic force. To put it simply, a dynamic force involves acceleration, were a static force does not.
The relationship between dynamic force and acceleration is described by Newton’s second law; F=ma (force equals mass times acceleration). The force required to stop your car with its substantial mass would a dynamic force, as the car must be decelerated. The force exerted by the brake caliper in order to stop that car would be a static force because there is no acceleration of the brake pads involved.
Torque is just a rotational force, or a force through a distance. From the previous discussion, it is considered static if it has no angular acceleration. The torque exerted by a clock spring would be a static torque, since there is no rotation and hence no angular acceleration. The torque transmitted through a cars drive axle as it cruises down the highway (at a constant speed) would be an example of a rotating static torque, because even though there is rotation, at a constant speed there is no acceleration.
The torque produced by the cars engine will be both static and dynamic, depending on where it is measured. If the torque is measured in the crankshaft, there will be large dynamic torque fluctuations as each cylinder fires and its piston rotates the crankshaft.
If the torque is measured in the drive shaft it will be nearly static because the rotational inertia of the flywheel and transmission will dampen the dynamic torque produced by the engine. The torque required to crank up the windows in a car (remember those?) would be an example of a static torque, even though there is a rotational acceleration involved, because both the acceleration and rotational inertia of the crank are very small and the resulting dynamic torque (Torque = rotational inertia x rotational acceleration) will be negligible when compared to the frictional forces involved in the window movement.
This last example illustrates the fact that for most measurement applications, both static and dynamic torques will be involved to some degree. If dynamic torque is a major component of the overall torque or is the torque of interest, special considerations must be made when determining how best to measure it.
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How Beans Grow
by National Gardening Association Editors
If you've ever walked by containers of bulk seed in a garden store, you may have been surprised by the many different colors, sizes and shapes of the beans -- even by the variety of designs on the seed coats and their descriptive names: 'Soldier', 'Wren's Egg', 'Yellow Eye', 'Black Eye', and others.
Maybe you were impressed, too, with how big some of these seeds are. Underneath the large, hard seed coat is an embryo, a tiny plant ready to spring to life. When you plant a bean seed, the right amount of water, oxygen and a warm temperature (65°F to 75°F) will help it break through its seed coat and push its way up through the soil.
The Seed of Life
Most of the energy the young plant needs is stored within the seed. In fact, there's enough food to nourish bean plants until the first true leaves appear without using any fertilizer at all.
As the tender, young beans come up, they must push pairs of folded seed leaves (or cotyledons) through the soil and spread them above the ground. Beans also quickly send down a tap root, the first of a network of roots that will anchor the plants as they grow. Most of the roots are in the top eight inches of soil, and many are quite close to the surface.
What Beans Need
Beans need plenty of sunlight to develop properly. If the plants are shaded for an extended part of the day, they'll be tall and weak. They'll be forced to stretch upward for more light, and they won't have the energy to produce as many beans.
The bean plant produces nice, showy flowers, and within each one is everything that's necessary for pollination, fertilization and beans. Pollination of bean flowers doesn't require much outside assistance -- a bit of wind, the occasional visit from a bee, and the job is done. After fertilization occurs, the slender bean pods emerge and quickly expand. Once this happens, the harvest isn't far off.
Although beans love sun, too much heat reduces production. Bean plants, like all other vegetables, have a temperature range that suits them best: They prefer 70°F to 80°F after germinating. When the daytime temperature is consistently over 85°F, most beans tend to lose their blossoms. That's why many types of beans don't thrive in the South or Southwest in the middle of the summer -- it's simply too hot.
Beans don't take to cold weather very well, either. Only Broad or Fava beans can take any frost at all. Other types must be planted when the danger of frost has passed and the soil has warmed up.
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- Hypothermia occurs when the body's core temperature drops below 37°C.
- This typically results from prolonged exposure to cold conditions, especially in damp, wet or snowy weather.
- Early signs: shivering; listlessness; cold, pale, puffy face; impaired speech and impaired judgment.
- Later signs: drowsiness, weakness, slow pulse, shallow breathing, confusion, altered behaviour, stumbling, unsteadiness.
- Move person to warmer area, shield from cold, passive rewarming with space blanket etc., give warm fluids and high energy foods if possible.
What is hypothermia and what causes it?
Hypothermia occurs when the body's core temperature drops below 37°C. This happens when more heat is lost than the body can produce through shivering and muscle contractions.
Hypothermia is the result of prolonged exposure to cold conditions, especially in damp, wet or snowy weather. Inadequate clothing during winter or at night in the wilderness, or falling into cold water, are examples of situations which commonly cause hypothermia. Inactivity rapidly leads to heat loss and this is worse if the person is injured.
Symptoms and signs of hypothermia
Hypothermia has a gradual onset and the affected person might lose heat to a critical level before becoming aware of the problem. Early signs include shivering (shivering stops once body temperature falls to below 32°C); listlessness; a cold, pale, puffy face; slurred or incoherent speech and impaired judgment. This decrease in mental sharpness typically results in someone becoming unaware of the gravity of the situation.
Later signs, indicating severe hypothermia, include an overwhelming drowsiness and weakness, slow pulse and shallow breathing, confusion, altered behaviour such as aggressiveness, stumbling when walking and unsteadiness when standing.
Infants, the very lean and the elderly are at particular risk. Elderly people may become hypothermic at temperatures as mild as 10 to 15°C, particularly if they are malnourished, have heart disease or an underactive thyroid, or if they take certain medications or abuse alcohol.
Hypothermia can be fatal and therefore needs prompt treatment. Severe hypothermia may be difficult to distinguish from death because pulses become very difficult or impossible to feel and breathing may be too shallow to notice.
First aid for hypothermia
- Call for an ambulance if the person's level of consciousness is dropping, or you have any doubt about the severity of the condition.
- If possible, move the person to a warmer area, shielded from the cold and wind. Remove wet clothing.
- Passively re-warm the person by wrapping him in a space blanket, blankets, clothing or newspapers, and cover the head. If outdoors, insulate the person from the ground and lie next to him.
- If the person is conscious, give warm fluids and high-energy foods, unless he is vomiting. Don't give any alcohol or caffeinated drinks.
- Keep the person still as movement draws blood away from the vital organs. Don't massage or rub someone with severe hypothermia, or jostle them during transport. (Cold can interfere with the electric conduction system of the heart, making it prone to irregular rhythms which may lead to cardiac arrest.)
- Do not apply direct heat, such as a hot bath, heating pad or electric blanket. (This is called active re-warming and should not be done unless the person is very far from definitive care, as it carries a risk of burns.)
Prevention of hypothermia
- If you're going to be doing outdoor sports like hiking, research the conditions first and speak to experienced people who know the area. Ask them what they would recommend in terms of gear and available shelter. As a general rule: take along several layers of warm clothing (layers help trap warmed air) and keep the head, hands and feet covered.
- Change out of wet clothes as soon as you can. Being wet and in the wind rapidly speeds up heat loss from the body.
- Take along sufficient food, especially carbohydrates, and snack regularly. It's also important to stay hydrated, even in cold weather.
- Carry a space blanket; these are available at outdoor and camping shops.
Reviewed by Barry Milner, Instructor, Blue Star Academy of First Aid, BLS National Faculty and First Aid Representative (Resuscitation Council of Southern Africa)
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Most common smoke detectors (Fig. 13-2) contain a small amount of 241Am, a radioactive isotope. 241Am is produced and recovered from nuclear reactors. Alpha particles emitted by the decays of 241Am ionize the air (split the air molecules into electrons and positive ions) and generate a small current of electricity that is measured by a current-sensitive circuit. When smoke enters the detector, ions become attached to the smoke particles, which causes a decrease in the detector current. When this happens, an alarm sounds. These detectors provide warning for people to leave burning homes safely. Many lives have been saved by the their use.
Because the distance alpha particles travel in air is so short, there is no risk of being exposed to radiation by having a smoke detector in the house. Since ionization-type smoke detectors contain radioactive materials, they should be recycled or disposed of as radioactive waste. It is important to follow the instructions that come with the smoke alarm when they need to be discarded.
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Lesson Plans and Worksheets
Browse by Subject
Blood Teacher Resources
Find teacher approved Blood educational resource ideas and activities
A series of diagrams and photographs is a vivid tool for delivering a lesson about blood vessels. Each slide has notes for the lecturer to use to explain each slide. Your young biologists will increase their understanding of the structure and function of arteries, veins, and capillaries. The final slide provides a comparison chart for them to copy and complete as a review of the information absorbed.
A thorough commentary on blood type is presented in this handout. Antigens and antibodies are defined. Punnett squares and a pedigree chart help to clarify. Human biology or genetics learners then apply their knowledge to two situations: two newborn baby girls being possibly switched in the hospital and a crime scene investigation. This is an engaging activity that ends with a lab activity simulating the blood typing and identification of the perpetrator.
Although there are vocabulary terms in this PowerPoint that use British spelling, the presentation is attractive and educational. The content flows from the general composition of blood, into the different types of blood cells and their functions. The concluding slide has review questions that you can use to assess student retention.
In this blood type worksheet, students create a wheel showing blood type, antigens and the genes involved in coding for each blood type. Students use the wheel to answer 16 questions about blood type and they complete a chart with the genes, antigens and blood types using what they learned from the wheel.
In this simulation activity, young biologists examine blood types to determine whether the death rate in a hospital was caused because of incorrect identification of patient blood types. You will need obtain and follow the procedures of a blood typing kit in order carry out this lab activity in your classroom. Using this scenario makes a blood typing or scientific method lesson more interesting, and the provided lab sheet makes it easier for you to implement.
There are factors that can be controlled and factors that can't be controlled regarding blood pressure. Read through these handouts and learn about the different factors. Then answer some questions about the information just learned. There is even an activity to determine resting heart rate, and then to make calculations regarding one's target heart rate range. Discover why all of this information is important.
In this blood worksheet, students watch a video called "The Epic Story of Blood" and answer 24 questions about the creation of blood, how it is produced, blood donation, blood banks and transfusions. Students take an short quiz about the blood and what they learned in the video.
Here is a sharp presentation on multiple alleles using the classic blood type example. Viewers revisit codominance and dominance and learn that blood type is actually a combination of both. They use Punnett squares to solve blood type problems. They learn about agglutination and antibodies that make blood type crossing a topic of study. Follow this PowerPoint with a blood typing lab activity and more Punnett square practice.
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Carl Friedrich Gauss (1777-1855) is considered to be the greatest German mathematician of the nineteenth century. His discoveries and writings influenced and left a lasting mark in the areas of number theory, astronomy, geodesy, and physics, particularly the study of electromagnetism.
Gauss was born in Brunswick, Germany, on April 30, 1777, to poor, working-class parents. His father labored as a gardner and brick-layer and was regarded as an upright, honest man. However, he was a harsh parent who discouraged his young son from attending school, with expectations that he would follow one of the family trades. Luckily, Gauss' mother and uncle, Friedrich, recognized Carl's genius early on and knew that he must develop this gifted intelligence with education.
While in arithmetic class, at the age of ten, Gauss exhibited his skills as a math prodigy when the stern schoolmaster gave the following assignment: "Write down all the whole numbers from 1 to 100 and add up their sum." When each student finished, he was to bring his slate forward and place it on the schoolmaster's desk, one on top of the other. The teacher expected the beginner's class to take a good while to finish this exercise. But in a few seconds, to his teacher's surprise, Carl proceeded to the front of the room and placed his slate on the desk. Much later the other students handed in their slates.
At the end of the classtime, the results were examined, with most of them wrong. But when the schoolmaster looked at Carl's slate, he was astounded to see only one number: 5,050. Carl then had to explain to his teacher that he found the result because he could see that, 1+100=101, 2+99=101, 3+98=101, so that he could find 50 pairs of numbers that each add up to 101. Thus, 50 times 101 will equal 5,050.
At the age of fourteen, Gauss was able to continue his education with the help of Carl Wilhelm Ferdinand, Duke of Brunswick. After meeting Gauss, the Duke was so impressed by the gifted student with the photographic memory that he pledged his financial support to help him continue his studies at Caroline College. At the end of his college years, Gauss made a tremendous discovery that, up to this time, mathematicians had believed was impossible. He found that a regular polygon with 17 sides could be drawn using just a compass and straight edge. Gauss was so happy about and proud of his discovery that he gave up his intention to study languages and turned to mathematics.
Duke Ferdinand continued to financially support his young friend as Gauss pursued his studies at the University of Gottingen. While there he submitted a proof that every algebraic equation has at least one root or solution. This theorem had challenged mathematicians for centuries and is called "the fundamental theorem of algebra".
Gauss' next discovery was in a totally different area of mathematics. In 1801, astronomers had discovered what they thought was a planet, which they named Ceres. They eventually lost sight of Ceres but their observations were communicated to Gauss. He then calculated its exact position, so that it was easily rediscovered. He also worked on a new method for determining the orbits of new asteroids. Eventually these discoveries led to Gauss' appointment as professor of mathematics and director of the observatory at Gottingen, where he remained in his official position until his death on February 23, 1855.
Carl Friedrich Gauss, though he devoted his life to mathematics, kept his ideas, problems, and solutions in private diaries. He refused to publish theories that were not finished and perfect. Still, he is considered, along with Archimedes and Newton, to be one of the three greatest mathematicians who ever lived.
|Contributed by Karolee Weller|
|Permission was requested by Michael Sirola in Tampere, Finland to translate this biography into Finnish for his blog. To read the Finnish translation goto http://www.designcontest.com/show/twsu-math-fi|
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Spider silk can be scary enough to insects to act as a pest repellant, researchers say.
These findings could lead to a new way to naturally help protect crops, scientists added.
Spiders are among the most common predators on land. Although not all spiders weave webs, they all spin silk that may serve other purposes. For instance, many tiny spiders use silk balloons to travel by air.
Science news from NBCNews.com
Researchers suspected that insects and other regular prey of spiders might associate silk with the risk of getting eaten. As such, they reasoned silk might scare insects off.
The scientists experimented with Japanese beetles (Popillia japonica) and Mexican bean beetles (Epilachna varivestis). These plant-munching pests have spread across eastern North America within the past half-century. [ Ewww! Nature's Biggest Pests ]
The beetles were analyzed near green bean plants (Phaseolus vulgaris) in both the lab and a tilled field outdoors. The investigators applied two kinds of silk on the plants — one from silkworms (Bombyx mori) and another from a long-jawed spider (Tetragnatha elongata), a species common in riverbank forests but not in the region the researchers studied.
Both spider and silkworm silk reduced insect plant-chewing significantly. In the lab, both eliminated insect damage entirely, while in the field, spider silk had a greater effect — plants enclosed with beetles and spider silk experienced about 50 percent less damage than leaves without spider silk, while silkworm silk only led to about a 10 to 20 percent reduction. Experiments with other fibers revealed that only silk had this protective effect.
"This work suggests that silk alone is a signal to potential prey that danger is near," researcher Ann Rypstra, an evolutionary ecologist at Miami University in Ohio, told LiveScience.
Rypstra was most surprised that the effect occurred even though the species involved do not share any evolutionary history together as predator and prey. This suggests "herbivores are using the silk as some sort of general signal that a spider — any ol' spider — is around and responding by reducing their activity or leaving the area," she said.
While more work will need to be done before this research might find applied use, the fact that the presence of silk alone reduced damage caused by two economically important pest insects "suggests that there could be applications in agricultural pest management and biological control," Rypstra said.
Rypstra is also interested in the chain reaction of events that silk might trigger in an ecosystem.
"For example, if an herbivore encounters a strand of silk and alters its behavior in a particular manner, does that make it more susceptible to predation by a non-spider?" Rypstra asked. "Do spiders that leave lots of silk behind have a larger impact in the food web, and how does it vary from habitat to habitat? These are just a couple of questions that we might be exploring in the near future."
Rypstra and her colleagues detailed their findings online Wednesday in the journal Biology Letters.
- Gallery: Spooky Spiders
- What Really Scares People: Top 10 Phobias
- Gallery: Dazzling Photos of Dew-Covered Insects
© 2012 LiveScience.com. All rights reserved.
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Standing Bear in his formal attire
National Anthropological Archives, Smithsonian Institution
On their journey westward in 1804, Lewis and Clark learned about the Ponca, a small tribe living on the west bank of the Missouri River and along what are now the lower Niobrara River and Ponca Creek in northeast Nebraska. The two did not meet as the tribe was on a hunting trip to the west.
Early Life And Movement To Reservation
Standing Bear was born around 1829 in the traditional Ponca homeland near the confluence of the Niobrara and Missouri rivers. About thirty years later, the tribe sold its homeland to the United States, retaining a 58,000-acre reservation between Ponca Creek and the Niobrara River. On this reservation the Poncas lived a life of hardscrabble farming and fear-the United States did little to protect them from attacks from the Brule Sioux.
When the federal government created the Great Sioux Reservation in 1868, the Ponca Reservation was included within its boundaries, depriving them of title to their remaining lands.
Eviction And Removal
In 1877, the federal government decided to remove the Poncas to Indian Territory. Standing Bear, a tribal leader, protested his tribe's eviction. Federal troops enforced the removal orders, with the result that the Poncas arrived in Indian Territory in the summer of 1878. Discouraged, homesick and forlorn, the Poncas found themselves on the lands of strangers, in the middle of a hot summer, with no crops or prospects for any as the time for planting was long past.
Since the tribe had left Nebraska, one-third had died and nearly all of the survivors were sick or disabled. Talk around the campfire revolved around the "old home" in the north. The death of Chief Standing Bear's sixteen-year old son in late December 1878 set in motion the event which was to bring a measure of justice and worldwide fame to the chief and his small band of followers.
Honoring A Son's Wish
Wanting to honor his son's last wish to be buried in the land of his birth and not in a strange country where his spirit would wander forever, Standing Bear gathered a few members of his tribe-mostly women and children-and started for the Ponca homeland in the north. They left in early January 1879 and trekked through the Great Plains winter, reaching the reservation of their relatives, the Omahas, about two months later. Standing Bear carried with him the bones of his son to be buried in the familiar earth along the Niobrara River.
The Court Case - Standing Bear v. Crook
Because Indians were not allowed to leave their reservation without permission, Standing Bear and his followers were labeled a renegade band. The Army, on the order of The Secretary of the Interior, arrested them and took them to Fort Omaha, the intention being to return them to Indian Territory. General George Crook, however, sympathized with Standing Bear and his followers and asked Thomas Henry Tibbles, an Omaha newspaperman, for help. Tibbles took up the cause and secured two prominent Omaha attorneys to represent Standing Bear.
The lawyers filed a federal court application for a writ of habeas corpus to test the legality of the detention, basing their case on the 14th Amendment to the Constitution. The government disputed the right of Standing Bear to obtain a writ of habeas corpus on the grounds that an Indian was not a "person" under the meaning of the law.
Death And Commemoration
The case of Standing Bear v. Crook began on May 1, 1879 before Judge Elmer S. Dundy in U.S. District Court in Omaha and continued into the evening of the following day. On May 12, Judge Dundy ruled in favor of Standing Bear, reasoning that he and his band were indeed "persons" under the law, entitled to sever tribal connections and were free to enjoy the rights of any other person in the land. The government appealed Dundy's decision, but the Supreme Court of the United States refused to hear the case, leaving Standing Bear and his followers free in the eyes of the law.
Standing Bear died in 1908 and was buried alongside his ancestors in the Ponca homeland. At the eastern end of the 39-mile reach of the Missouri National Recreational River is a relatively new bridge. It links the communities of Niobrara, Nebraska, and Running Water, South Dakota. The official name of the structure is the Chief Standing Bear Memorial Bridge.
Click here for more details on Standing Bear and the Ponca Tribe, with a list of suggested additional reading. (PDF file)
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S-1. Sunlight & Earth
S-1B. Global Climate
S-3.The Magnetic Sun
S-4. Colors of Sunlight
Optional: Doppler Effect
S-4A-1 Speed of Light
S-4A-2. Frequency Shift
S-4A-3 Rotating Galaxies
and Dark Matter
S-5.Waves & Photons
Optional: Quantum Physics
Q3. Energy Levels
Q4. Radiation from
One widely used property of waves is the shift in frequency when the source approaches or recedes. If the engine of a train blows its whistle as it passes by, a listener standing near the track cannot help but notice that the tone of the whistle drops as it passes.
Actually, the tone is already raised above its normal note as the engine approaches, and then drops below it as it recedes. This shift in frequency, also noted in electromagnetic waves such as light or radio, is named the Doppler Effect after its discoverer, the Austrian Christian Doppler, born in 1803.
Earlier, a somewhat similar phenomenon was discovered by the Dane Ole Roemer in 1676. The story deserves to be told because it also led to the first determination of the velocity of light.
Those were the times when the sailing ships of seafaring nations – especially, France, Spain, Britain and the Netherlands (Holland) – fought to dominate the oceans and to establish (and protect) trade routes and distant bases. In such a struggle, one technology was crucial: commanders of ships had to somehow know at all times their position in mid-ocean, that is, their latitude and longitude.
Latitude was relatively easy: the elevation of the celestial pole above the horizon (deduced, for instance, from the position of the pole star) gave that. Or else, the elevation of the Sun when it was most distant from the horizon ("solar noon"), i.e. made the greatest angle between it and the horizon, gave the latitude (after being adjusted for the day of the year). The cross staff, or a later more accurate instrument, the marine sextant (or the octant) allowed "shooting the Sun," i.e. finding its elevation above the horizon, and by combining several timed observations, its greatest elevation for that day could be derived.
Longitude was much harder. It required knowledge of the time at Greenwhich (longitude zero) when a cross staff or sextant determined that the Sun was passing local noon. For example, if the Sun passed local noon when it was 1 p.m. at Greenwich, the ship was 15° west of Greenwich, because
To get this information, the captain needed a clock which kept accurate time for a many months: it could be set in Greenwich (or set to Greenwich time at a location of known longitude), and used later to give "Greenwich time" of local noon. Such clocks ("chronometers") were in fact developed in the 1700s, but clocks of the 1600s were not accurate enough, especially on a ship that rolled and pitched, and their errors accumulated rapidly.
A less precise clock may be used, if somehow it can be constantly corrected, reset to the correct "Greenwich time" at frequent intervals. In a later era this was done using time signals obtained by radio, but in the 1600s accurately timed celestial phenomena held the greatest promise. One class of such phenomena were the eclipses of the four large moons of Jupiter, discovered by Galileo and easily seen through even a small telescope.
In particular, Io, the innermost moon of Jupiter, seemed suitable: being closest to Jupiter, Kepler's 3rd law assured that it had the fastest motion, making its entry into eclipses and out of them particularly rapid. With an orbital period of 1.77 days, Io also offered the largest number of eclipses, and every one of its orbits crossed Jupiter's shadow. (In the satellite age Io was found to have other unique features, such as sulfur volcanoes.)
Giovanni Domenico Cassini, an Italian astronomer who headed of the Paris Observatory, therefore assigned Roemer to make a table of the predicted times of Io eclipses, allowing sailors at sea to set their clocks (within a minute or so, deemed accurate enough). Roemer did so, but soon discovered that the period was not constant. When Earth (which moves faster than Jupiter) was approaching Jupiter, the observed period was shorter, and when it was receding, longer.
He guessed the reason: light did not spread instantly, but (like sound) did so at a certain speed. If Earth and Jupiter maintained a constant distance, the eclipses would have been spaced at regular intervals, equal to the orbital period of Io. When Earth is approaching, however, the return trip is shortened, compared to the time it would have taken if the distance stayed constant. When Earth is receding, the return trip is longer, and the time between eclipses is longer too
That gave Roemer convincing evidence that light spread in space with a certain velocity--later denoted by the letter c (lower case, not capital). However, he and his contemporaries had only a vague idea how big c was, because the dimensions of the solar system were uncertain. About that same time, the French astronomer Jean Richer used a telescope to estimate of the distance of Mars, and gradually, the value of c was obtained with increasing accuracy. Today it is known to an accuracy of 9 decimals, and has therefore been used to define the metre, the unit of length, replacing optical wavelengths or scratches on a metal bar kept in a vault (supposedly derived from the size of our globe).
And the problem of longitude?
It turned out that observing the eclipses of Io from a constantly moving ship, even in a calm sea, was a difficult task. Even a small telescope magnifies all motions tremendously, and early telescopes in particular showed only a small patch of the sky. Also, the method required a sky free of clouds. On the other hand, the method proved very useful for determining the longitude of ports, capes, islands and other features on land.
Consistent determinations of longitude from a moving ship had to wait for sophisticated clocks, using a balance wheel compensated for changes due to variation of temperature. One early model of such a "chronometer" accompanied Captain James Cook on his journey around the world.
(S-4A-2) The Frequency Shift and the Expanding Universe
(S-5) Waves and Photons
Timeline Glossary Back to the Master List
Author and Curator: Dr. David P. Stern
Mail to Dr.Stern: stargaze("at" symbol)phy6.org .
Last updated: 9 December 2006
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Teacher's Resources - A Question of Ritual
For the people of the ancient Americas as for many other humans worldwide, ceremonies formed a bridge between their world and that of deities and spirits. Through sacred rituals they communicated to their gods and ancestors their hopes for a bounty of food, protection from the potential disasters wrought by nature or political enemies and general good fortune, thus forming a bridge between the living and the metaphysical.
In the Mesoamerican and Andean belief systems, many different rituals involving dances, ceremonies, festivals and games were performed to maintain a sense of order and balance and to create the conditions necessary for prosperous human cultures to unfold. Much has been made of the evidence for the practice of human sacrifice in both regions; certainly it appears to have been practiced, as it was in certain civilizations all over the world, including Imperial Rome, the early Celtic settlements of Western Europe, and many others.
What is more interesting and fruitful to pursue with students is an exploration of the possible belief systems that gave meaning to the CLOTH & CLAY objects, such as this ritual incense burner from Teotihuacan, an ancient Mexican culture.
Classroom Activities and Projects (recommended ages are in italics and are approximate)
1. 12 -16: In groups or as individuals, students can research the symbolism of the mountain in ancient American cultures, investigating such areas as sacred geometry, layout of cities and ritual sites, pyramids, and rituals. The results of the research can result in essays, as well as drawings and 3-dimensional models.
2. 12 -16: Within a larger project comparing the beliefs of ancient peoples around the world, students can investigate those of the ancient Americas, including shamanism, use of psychotropic plants, and human sacrifice, tying these practices to the religious beliefs of the cultures practicing them. Class discussions can touch on how easy it is to sensationalize these practices, and the importance of putting them in context with the larger belief systems of the civilizations under review.
3. 12 - 16: Research on the Day of the Dead, a yearly festival in Mexico that takes place in early November, provides insight into ancient and contemporary religious beliefs and rituals. By studying this and other festivals, students who are growing up in the secular societies of the West can develop an understanding of life in a deeply religious culture. Similarly, students who are themselves rooted in a religious culture can learn about other belief systems.
In its original form, this festival took place during Miccailhuitontli (late summer) in the Aztec calendar, and celebrated the life cycle, honouring the newly dead and the ancestors. Today the day corresponds to All Saints Day in the Christian calendar.
Students working in groups can present the results of their research to the class, with each group covering different aspects of the festival such as the variety of forms taken by the festivities, the combined Christian/pre-Christian elements, and the significance of ofrendas, calaveras and other related objects.
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Until the Aswan High Dam was built, Egypt received a yearly inundation - an annual flood - of the Nile. The ancient Egyptians did not realise this, but the flood came due to the heavy summer rains in the Ethiopian highlands, swelling the different tributaries and other rivers that joined and became the Nile. This happened yearly, between June and September, in a season the Egyptians called akhet - the inundation. This was seen by the Egyptians as a yearly coming of the god Hapi, bringing fertility to the land.
The first signs of the inundation were seen at Aswan by the end of June, reaching its swelling to its fullest at Cairo by September. The flood would then decrease in size around two weeks later, leaving behind a deposit of rich, black silt. The amount of silt left behind due to the height of the Nile determined the amount of crops that the Egyptians could grow - if the inundation was too low, it would be a year of famine.
The Egyptians learned a method of measuring the height of the Nile known as the Nilometre.
Although all Nilometres used by the Egyptians had a single obvious purpose, to mark the highest point of Inundation, they were constructed in one of three different formats -- a slab or pillar, a well or a series of steps. All three were calibrated using the same unit of measurement, the cubit; the Egyptians broke the cubit into smaller units, which allowed them to keep remarkably accurate records, perhaps more accurate than would have been warranted for the purposes of merely agriculture and taxation.
The Nilometre on Elephantine Island near the First Cataract deep in southern Egypt always held supreme importance. It was the first outpost where the floods exerted themselves and the first to know when they were over, but the religious significance of the might might have overshadowed its strategic location. It was the home-place of Khnum, the ram-headed god of Inundation. During the Eleventh Dynasty a sanctuary was built on the island specifically to celebrate Inundations. A new Nilometre replaced a much older one at the edge of Khnum's Temple during the Twenty-Sixth Dynasty; somewhat later, in Dynasty Thirty, a riverside terrace and another Nilometre was added to the nearby Temple of Satet, one of Khnum's celestial consorts. When Egypt fell to Rome, that did not mean an end to Nilometres on Elephantine Island, for Khnum's Nilometre received a new calibrated staircase and a granite roof from the Romans.
-- Ralph Vaughan, Nilometers: Measuring the Universe
The Nilometres were usually a series of steps by the Nile, where the water level against the steps would show how high the Nile would rise and records of the maximum height of the inundation could be taken. There are Nilometres at the temples at Elephantine, Philae, Edfu, Esna, Kom Ombo and Dendera. These were build through pharaonic times up until Roman times. There was even a Nilometre built during early Islamic times at el-Rhoda in Cairo, which was possibly the site of an ancient Nilometre, though it used a pillar rather than the usual steps.
The ancient Egyptians viewed Sirius as the bringer of new life. This was because Sirius was newly visible in the sky at the time of the flooding of the Nile River, the life-giving inundation which yearly fertilised their crops.
The inundation was also around the time that the Egyptians noticed the rising of the 'dog star' Sirius. The goddess Sopdet (Sothis) was the personification of this star, represented as a woman with a star as her headdress, or as a seated cow with a plant between her horns (just as Seshat's hieroglyph might have been a flower or a star.) Her star was the most important of the stars to the ancient Egyptians, and the rising of this star came at the time of inundation and the start of the Egyptian new year. She was linked closely with Isis, just as her husband Sah (the star Orion) and son Soped were linked with Osiris and Horus.
Isis' sister Nephthys is also somewhat linked to the inundation - in one particular tale, she represents the desert while Osiris represents the inundation itself. When the Nile flood is high enough to reach the desert, flowers bloom in the barren red land. In the story, Osiris and Nephthys have a drunken union, where Osiris leaves behind his garland of melilot flowers. As the inundation was a sign of fertility, Osiris and Nephthys were thought to have had a child - Anubis, god of mummification.
Now because the Ancient Egyptian calendar was slightly out of step with the solar and lunar year - the Egyptian calendar was out by 6 hours. As time went on, the inundation came occasionally during the season of akhet, so the Egyptians relied on the star, rather than the season, as the herald of both the new year and the yearly flood.
The other two seasons were peret (growing) and shemu (harvest). During the growing season (after the inundation had receded, if not exactly in the season according to the calendar) the Egyptians planted their crops - around October and November - and tended to the fields. The Egyptians watered their crops using an irrigation system of canals or by bringing water to the fields in basins or by using the shaduf, which is still in use in Egypt today, to raise water from the river to the bank of the Nile. By the time the Nile reached its lowest level, some time around March or April, the crops would be ready for the harvest.
During the inundation, though, there was nothing to do for the Egyptian farmer. Rather than doing nothing for a whole season, the Egyptians would do other tasks rather than paying tax. (Tax was usually taken out of the crops that the farmers grew, and during inundation, the farmland was covered by water!) During the Old Kingdom, this work took on the form of working on building pyramids.
This was not done, as originally and incorrectly thought, by slave labour. In fact, it was done by Egyptian citizens who had little else to do for one season a year. These men were also 'paid' for their work - workmen at the pyramids of the Giza Plateau were given beer, thrice daily - five kinds of beer and four kinds of wine!
If Egypt had a drought or a year of plenty, it was the will of the Nile god Hapi. The Egyptians gave him offerings and worship to hopefully bring a good flood that wasn't too high or too low. They celebrated the 'Arrival of Hapi', hoping that their houses wouldn't be washed away, or that the Nile would rise enough to provide both water and silt for the farmland. But the Egyptians, despite being able to measure the flood, couldn't change the situation if the Nile's waters weren't at the required level. To them, the inundation was truly in the hands' of the gods.
Who are we?
Tour Egypt aims to offer the ultimate Egyptian adventure and intimate knowledge about the country. We offer this unique experience in two ways, the first one is by organizing a tour and coming to Egypt for a visit, whether alone or in a group, and living it firsthand. The second way to experience Egypt is from the comfort of your own home: online.
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Want to stay on top of all the space news? Follow @universetoday on Twitter
Currently, astronomers have two competing models for planetary formation. In one, the planets form in a single, monolithic collapse. In the second, the core forms first and then slowly accretes gas and dust. However, in both situations, the process must be complete before the radiation pressure from the star blows away the gas and dust. While this much is certain, the exact time frames have remained another matter of debate. It is expected that this amount should be somewhere in the millions of years, but low end estimates place it at only a few million, whereas upper limits have been around 10 million. A new paper explores IC 348, a 2-3 million year old cluster with many protostars with dense disks to determine just how much mass is left to be made into planets.
The presence of dusty disks is frequently not directly observed in the visible portion of the spectra. Instead, astronomers detect these disks from their infrared signatures. However, the dust is often very opaque at these wavelengths and astronomers are unable to see through it to get a good understanding of many of the features in which they’re interested. As such, astronomers turn to radio observations, to which disks are partially transparent to build a full understanding. Unfortunately, the disks glow very little in this regime, forcing astronomers to use large arrays to study their features. The new study uses data from the Submillimeter Array located atop Mauna Kea in Hawaii.
To understand how the disks evolved over time, the new study aimed to compare the amount of gas and dust left in IC 348′s disc to younger ones in star forming regions in Taurus, Ophiuchus, and Orion which all had ages of roughly 1 million years. For IC 348, the team found 9 protoplanetary disks with masses from 2-6 times the mass of Jupiter. This is significantly lower than the range of masses in the Taurus and Ophiuchus star forming regions which had protoplanetary clouds ranging to over 100 Jupiter masses.
If planets are forming in IC 348 at the same frequency in which they form in systems astronomers have observed elsewhere, this would seem to suggest that the gravitational collapse model is more likely to be correct since it doesn’t leave a large window in which forming planets could accrete. If the core accretion model is correct, then planetary formation must have begun very quickly.
While this case don’t set any firm pronouncements on which model of planetary formation is dominant, such 2-3 million year old systems could provide an important test bed to explore the rate of depletion of these reservoirs.
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The Philippines had suffered under the Japanese occupation. A highly effective guerilla campaign controlled sixty percent of the islands, mostly jungle and mountain areas. MacArthur had supplied them by submarine, and sent reinforcements and officers. Filipinos remained loyal to the United States, partly because of the American guarantee of independence, and also because the Japanese had pressed large numbers of Filipinos into work details and even put young Filipino women into brothels.
MacArthur returned to the Philippines in force on October 20, 1944. He waded in with Philippine President Sergio Osmeña, restaging the landing a second time for the newsreel cameras. The US Army forces met resistance, but steadily advanced, until the landings at Ormoc on December 7, 1944. Most of the fighting was at sea during the Battle of Leyte Gulf.
Ormoc saw the widespread use of kamikazes while the Americans ran into fortified positions and heavy artillery. MacArthur fought north through the Philippines all through the Fall of 1944, reaching Manila and the main island of Luzon in January 1945. The initial landing in Lingayen Gulf was unopposed, sparing the Japanese a prolonged bombardment as they retreated inland. The Japanese had a network of caves, pillboxes, and artillery. The defenders hoped to prevent an invasion of the home islands by offering a stiff resistance in the Philippines.
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Evidence from caves in Siberia indicates that a global temperature increase of 1.5° Celsius may cause substantial thawing of a large tract of permanently frozen soil in Siberia. The thawing of this soil, known as permafrost, could have serious consequences for further changes in the climate.
Permafrost regions cover 24 percent of the land surface in the northern hemisphere, and they hold twice as much carbon as is currently present in the atmosphere. As the permafrost thaws, it turns from a carbon sink (meaning it accumulates and stores carbon) into a carbon source, releasing substantial amounts of carbon dioxide and methane into the atmosphere. Both of these gasses enhance the greenhouse effect.
By looking at how permafrost has responded to climate change in the past, we can gain a better understanding of climate change today. A team of international researchers looked at speleothems, such as stalagmites, stalactites, and flowstones. These are mineral deposits that are formed when water from snow or rain seeps into the caves. When conditions are too cold or too dry, speleothem growth ceases, since no water flows through the caves. As a result, speleothems provide a detailed history of periods when liquid water was available as well as an assessment of the relationship between global temperature and permafrost extent.
Using radioactive dating and data on growth from six Siberian caves, the researchers tracked the history of permafrost in Siberia for the past 450,000 years. The caves were located at varying latitudes, ranging from a boundary of continuous permafrost at 60 degrees North to the permafrost-free Gobi Desert.
In the northernmost cave, Lenskaya Ledyanaya, no speleothem growth has occurred since a particularly warm period around 400,000 years ago—the growth at that time suggests water was flowing in the area due to a melt in the permafrost. The extensive thawing at that time allows for an assessment of the warming required globally to cause a similar change in the permafrost boundary. Global temperatures at that time were only 1.5°C warmer than today, suggesting that we could be approaching a critical point at which the coldest permafrost regions would begin to thaw.
Not only will increasing global temperatures cause substantial thawing of permafrost, but it may also create wetter conditions in the Gobi Dessert, based on data from the southern-most cave obtained for the same time period. This suggests a dramatically changed environment in continental Asia.
Aside from changes in temperature and precipitation, thawing permafrost enables coastal erosion and the liquefaction of ground that was previously frozen. This poses a risk to the infrastructure of Siberia, including major oil and gas facilities.
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Storytelling in the Classroom
Storytelling is not the same as reading aloud because it requires greater interaction between the teller and the listener. Therefore, storytelling is a great tool for improving children's communication skills, as well as developing language skills, comprehension, and self-awareness. (Reading and Communication Skills)
To help students use storytelling to foster creativity and to develop social skills and language skills—speaking, listening, and comprehension
Print out selected Building Blocks Character Cards, Know-Kit Cards, character bios, and ABC Coloring Book pages.
If you're going to use the Optional Activity for Older Students, gather a variety of at least 10 to 12 everyday items (pencil, spoon, umbrella, pair of shoes, tape, etc.).
- Gather the students in a large group. Choose a Building Blocks character picture and introduce him or her as a new student in the class. Tell the students some important things to know about their new friend based on the character cards and biography. We will use Ali Rabbit for our example.
Ali Rabbit is 5 years old. He lives with his mom, dad, grandparents, and great grandpa. He has six brothers and sisters. The oldest is aged 17 and the youngest is 5. His favorite sport is soccer. He likes to play on the computer and make music. His good friend is Thurgood Turtle.
- Now, start a story about Ali Rabbit's first day in your classroom. Include specific places and people in the story—the bus driver, the media specialist, etc. Model good storytelling practices for the students to remind them to speak clearly and loudly and to express feelings as they tell the story. Is Ali excited, frightened, or shy about his first day at a new school?
- Then, pass the picture of Ali to a student and have him or her add to the story. Continue passing the picture around the class until Ali's first day at school is complete. You may need to ask questions to prompt the children’s imaginations.
- Next, divide the class into small groups. Select several Know-Kit Cards and/or ABC Coloring Book pages that show Ali Rabbit. For example: Ali asleep on the soccer field, Ali playing the keyboard, Ali crying when someone took away his keyboard, Ali eating peanut butter and apples, Ali at his fifth birthday party, or Ali with his friends.
- Let the group talk about the pictures as they put them into a sequence and begin to make up a story that goes with the pictures. Depending on the age of your students, you may have to help them decide on the sequence of the pictures they will use.
- Have each group come to the front of the class with their pictures and share their story. Have others in the class participate by asking questions about the story or the characters.
- Finally, mix up all the pictures and distribute them around the class. Start a story based on the picture you hold. Then, call on a child to add to your story, using the character in the picture he or she holds. Go around the room and call on students to add to the class story.
- Have the students talk about the different stories and tell what they liked best. Was it more fun to have planned a story with their small group or to mix and match stories as a whole group? Why?
Optional: For Older Students
Place all the everyday items you’ve gathered into a big box. Be sure not to let the students see what's in the box. Then, tell the students that they're going to tell a story using the props in the box. Pass out one prop to the first student and have him or her start the story. Then, in the middle of the story, pass out another prop to a different student, which is the cue to jump into the story. Continue this until all the props are given out. The stories should make everyone laugh with the mismatched items and complicated storyline.
You can start again using the same props, but in a different order. Or, you can have students find their own props to tell an add-on group story.
Please note—to view documents in PDF format, you must have Adobe’s free Acrobat Reader software. If you do not already have this software installed on your computer, please download it from Adobe's Web site.
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What's the Latest Development?
Using location data gathered by personal mobile phones, researchers from Carnegie Mellon University have created the first map that tracks the spread of malaria by examining movement patterns among Kenya's population. Between 2008 and 2009, researchers followed the movement of 15 millions Kenyans, out of a total population of close to 40 million. Then they combined the data with "maps of population distribution and malaria prevalence over the same period to create, for the first time, a map that correlates large-scale trends in movement to the spread of the disease."
What's the Big Idea?
Because of how malaria spreads, the disease is particularly sensitive to the movement of affected populations. "Malaria is usually associated with the bite of infected female mosquitoes. But once humans contract the disease, they can act as a vector if they are bitten by uninfected insects, which then spread the parasite to other people." Tom Scott of the Mosquito Research Laboratory at the University of California, Davis, said the research will be essential in finding and targeting the human transmission routes of the parasites that cause malaria.
Photo credit: Shutterstock.com
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Douglass Jacobs, an associate professor of forestry and natural resources, found that American chestnuts grow much faster and larger than other hardwood species, allowing them to sequester more carbon than other trees over the same period. And since American chestnut trees are more often used for high-quality hardwood products such as furniture, they hold the carbon longer than wood used for paper or other low-grade materials.
"Maintaining or increasing forest cover has been identified as an important way to slow climate change," said Jacobs, whose paper was published in the June issue of the journal Forest Ecology and Management. "The American chestnut is an incredibly fast-growing tree. Generally the faster a tree grows, the more carbon it is able to sequester. And when these trees are harvested and processed, the carbon can be stored in the hardwood products for decades, maybe longer."
At the beginning of the last century, the chestnut blight, caused by a fungus, rapidly spread throughout the American chestnut's natural range, which extended from southern New England and New York southwest to Alabama. About 50 years ago, the species was nearly gone.
New efforts to hybridize remaining American chestnuts with blight-resistant Chinese chestnuts have resulted in a species that is about 94 percent American chestnut with the protection found in the Chinese species. Jacobs said those new trees could be ready to plant in the next decade, either in existing forests or former agricultural fields that are being returned to forested land.
"We're really quite close to having a blight-resistant hybrid that can be reintroduced into eastern forests," Jacobs said. "But because American chestnut has been absent from our forests for so long now, we really don't know much about the species at all."…
Douglass Jacobs examines a young hybrid of the American chestnut. He expects the trees could be reintroduced in the next decade. (Purdue University file photo/Nicole Jacobs)
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