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|The incorporation of the Navajo into a global market meant that the weavers were increasingly incorporated into the cash economy of this market. The period from 1875 to 1890 is generally considered a transition period for the Navajo weavers. During this time they began to use commercial American-made yarns known collectively as Germantown. These yarns were dyed with aniline (a dye derived from coal tar) and provided primarily in 4-ply.
It was also during this transition period that a new element was added to Navajo weaving: the pictorial weaving. Items such as cows, trains, American flags, and other items began to appear in the weavings.
By 1887 the Indian superintendent for the Navajo estimated that two-thirds of their weavings-primarily blankets-were now being sold. Two years later, the Indian superintendent reports that while there were just nine federally licensed traders on the reservation, there were about 30 trading posts located just off the reservation. He noted that the
"proximity of trading posts has radically changed their native costumes and modified many of the earlier barbaric traits, and also affords them good markets for their wool, peltry, woven fabrics, and other products."
The Hubbell Trading Post is shown above.
By 1890, the Navajo were producing about $25,000 worth of trade goods each year. Their involvement with this larger market had an impact on native crafts. Since pottery and basketry did not have the same commercial appeal as other crafts, the people were producing less.
The Rug Period of Navajo Weaving is usually dated from 1890 to 1920. At this time, the weavers began making thicker weavings which could be used as rugs for sales outside of the reservation. Regional styles began to develop which were associated with traders or trading posts. The traders, sensitive to the tastes of non-Indians in distant markets, actively collaborated with the weavers to produce designs which would sell. One of the design features which was introduced in 1890 was the use of borders.
One of the major supporters of the Navajo rugs was the Harvey Company which featured them in their eating houses and newsstands along the route of the Atchison, Topeka, and Santa Fe Railroad. In 1900, the Harvey Company established the Indian Building in Albuquerque which featured Navajo weavers plying their craft so that the tourists could watch. Fred Harvey also contracted with the trader Lorenzo Hubbell to take his entire output of good quality Navajo weavings. Harvey insisted that the business needed standardization with regard to size, quality, and price.
Since the traders, particularly the Harvey Company, frowned on the use of Germantown yarn, the rugs tended to be woven with coarse handspun wool which was either dyed with aniline or left in its natural color. In 1897, J.B. Moore, who had the trading post at Crystal, New Mexico, began sending wool east to be washed and carded. This thoroughly cleaned wool could be more easily spun and consequently the technical quality of the rugs woven by the weavers in his area improved.
In addition to providing his weavers with cleaned wool, Moore also had a friend who designed some new styles using some traditional Navajo figures combined with non-Navajo motifs such as swastikas and frets which were common in the oriental rugs of this period. The patterns were enclosed by borders and favored natural wool colors: black, gray, brown, tan, and white.
Trader Juan Lorenzo Hubbell in the Ganado area encouraged weavers to use traditional Navajo designs from earlier time periods. In his trading post he hung watercolor design samples to help inspire the weavers.
The inside of the Hubbell Trading Post is shown above. Note the designs on the walls.
Shown above is a small rug in the razzle-dazzle style woven by a young girl and sold at the Hubbell Trading Post.
Shown above is an example of the Ganado Red style from my personal collection.
The Crystal tradition led to the distinctive style known as Two Gray Hills, named for the trading post on the east side of the Chuska Mountains south of Shiprock. At Two Gray Hills, the old Crystal style became elaborated and the technical excellence of spinning and weaving improved.
Shown above is a small Two Gray Hills rug from my personal collection.
The borders introduced by the Crystal tradition spread throughout the reservation and by 1910 could be found on most rugs.
In 1898, Navajo weavers responded to the patriotic fever of the Spanish-American War by making American flag blankets.
In 1903, John Lorenzo Hubbell began to provide Navajo weavers with commercially processed wool at his trading post in Ganado, Arizona. Other traders soon followed suit.
In 1910, the United States government in its infinite wisdom introduced Rambouillet sheep to the reservation. These sheep had oily, short-staple, crimpy wool rather than the long-staple wavy wool of the Navajo sheep. It is difficult, some say impossible, for a Navajo weaver to clean this wool with the traditional hand washing. Rugs woven from this wool were coarse and the whites tended to have a dirty gray cast. This helped bring Navajo weaving to a new low and by 1920 the demand for Navajo rugs and the prices paid for them had declined significantly.
In 1931, a group of traders, concerned about the protection of the Navajo rug, met in Gallup, New Mexico and formed the United Indian Traders Association. They advocated that the following standards to be used for Navajo blankets and rugs:
"Material used shall be virgin wool or virgin angora wool, the same shall be hand-washed, hand-carded and hand-dyed, the warp shall be all wool and hand-spun, the wool shall be all wool and hand-spun and the blanket shall be hand-woven by an Indian."
In 1932, a number of Navajo sheep ranchers attended the Denver stock show and as a result they acquired a prize-winning Dorset ram in an attempt to improve the quality of wool available for blankets.
Today, Navajo rugs continue to be popular and continue to battle against cheap, imported imitations which use Navajo designs or designs which pretend to be Navajo. There are well over a thousand weavers on the Navajo reservation who do museum quality work and tourists can obtain high quality rugs at most of the trading posts on the reservation. The Hubbell Trading Post, which played an important role in the development of twentieth century Navajo rugs, is currently operated by the National Park Service. Tourists visiting Hubbell can not only purchase high quality rugs, but can also watch the weavers in action. While it is not uncommon for tourists to grumble at what they perceive as the high prices for these rugs, keep in mind that most weavers make well under minimum wage for the hours they spend at the loom. |
CDC Says “Take 3” Actions To Fight The Flu
Flu is a serious contagious disease that can lead to hospitalization and even death.
CDC urges you to take the following actions to protect yourself and others from influenza (the flu):
- CDC recommends a yearly flu vaccine as the first and most important step in protecting against flu viruses.
- While there are many different flu viruses, a flu vaccine protects against the three viruses that research suggests will be most common. (See upcoming season’s Vaccine Virus Selection for this season’s vaccine composition.)
- Everyone 6 months of age and older should get a flu vaccine as soon as the current season's vaccines are available.
- Vaccination of high risk persons is especially important to decrease their risk of severe flu illness.
- People at high risk of serious flu complications include young children, pregnant women, people with chronic health conditions like asthma, diabetes or heart and lung disease and people 65 years and older.
- Vaccination also is important for health care workers, and other people who live with or care for high risk people to keep from spreading flu to high risk people.
- Children younger than 6 months are at high risk of serious flu illness, but are too young to be vaccinated. People who care for them should be vaccinated instead.
- Try to avoid close contact with sick people.
- If you are sick with flu-like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.)
- While sick, limit contact with others as much as possible to keep from infecting them.
- Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
- Wash your hands often with soap and water. If soap and water are not available, use an alcohol-based hand rub.
- Avoid touching your eyes, nose and mouth. Germs spread this way.
- Clean and disinfect surfaces and objects that may be contaminated with germs like the flu.
- See Everyday Preventive Actions [257 KB, 2 pages] and Nonpharmaceutical Interventions (NPIs) for more information about actions – apart from getting vaccinated and taking medicine – that people and communities can take to help slow the spread of illnesses like influenza (flu).
- If you get the flu, antiviral drugs can treat your illness.
- Antiviral drugs are different from antibiotics. They are prescription medicines (pills, liquid or an inhaled powder) and are not available over-the-counter.
- Antiviral drugs can make illness milder and shorten the time you are sick. They may also prevent serious flu complications. For people with high risk factors [702 KB, 2 pages], treatment with an antiviral drug can mean the difference between having a milder illness versus a very serious illness that could result in a hospital stay.
- Studies show that flu antiviral drugs work best for treatment when they are started within 2 days of getting sick, but starting them later can still be helpful, especially if the sick person has a high-risk health or is very sick from the flu. Follow your doctor’s instructions for taking this drug.
- Flu-like symptoms include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue. Some people also may have vomiting and diarrhea. People may be infected with the flu, and have respiratory symptoms without a fever.
Visit CDC’s website to find out what to do if you get sick with the flu and how to care for someone at home who is sick with the flu. |
English Language Learners
The population of English language learners (ELLs) in U.S. public schools is growing quickly. This section includes information on effective ways to teach ELL (also called ESL) students , methods for encouraging learning, and ways to promote family involvement. Please also visit our sister website Colorín Colorado, which focuses exclusively on ELLs.
See additional sources of reading research.
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A Cognitive Strategies Approach to Reading and Writing Instruction for English Language Learners in Secondary School
Copyright 2007 by the National Council of Teachers of English. Used with permission. Olson, C.B. and Land, R. (2007). A Cognitive Strategies Approach to Reading and Writing Instruction for English Language Learners in Secondary School. Research in the Teaching of English, 41(3), http://www.ncte.org/pubs/journals/rte/articles/126617.htm.
Cognitive strategies, such as predicting, summarizing, and reflecting-strategies used by experienced readers and writers, are vital to the development of academic literacy, but these strategies are too rarely taught explicitly, especially to English Language Learners (ELLs). This study reports the results of a California Writing Project study in which 55 teachers implemented a cognitive-strategies approach to reading and writing instruction for their ELL secondary students over an eight-year period and includes a detailed description of a teacher's cognitive strategies "tool kit."
Double the Work: Challenges and Solutions to Acquiring Language and Academic Literacy for Adolescent English Language Learners
Short, D., & Fitzsimmons, S. (2007). Double the Work: Challenges and solutions to acquiring language and academic literacy for adolescent English language learners– A report to Carnegie Corporation of New York. Washington, DC: Alliance for Excellent Education.
Adolescent English Language Learners (ELLs), who must simultaneously learn English and age–appropriate subject material, perform double the work of their native language peers because they are held to the same grade-level standards for academic literacy. Moreover, the ELL population is comprised of a diverse range of learners who vary dramatically in their existing literacy levels, native languages, and cultural and educational backgrounds. This report is the effort of a panel of researchers, policymakers, and practitioners to address six main challenges to improving academic literacy among ELLs, as well as proposed solutions and policy implications.
Improving Literacy Outcomes for ELLs in High School: Considerations for States and Districts in Developing a Coherent Policy Framework
Torgesen, J. K., Houston, D. D., Rissman, L. M., Decker, S. M., Roberts, G., Vaughn, S., Wexler, J. Francis, D. J, Rivera, M. O., Lesaux, N. (2007). Academic literacy instruction for adolescents: A guidance document from the Center on Instruction. Portsmouth, NH: RMC Research Corporation, Center on Instruction.
This overview from the National High School Center examines the roles of states and school districts in supporting English Language Learners. Among the key findings — ELL students who access accelerated and enriching academics rather than remediation, succeed at higher levels, and Latino ELL students are overrepresented in special education. To build the capacity of teachers to appropriately identify which ELL students would benefit from special education services and which would benefit from more inclusive strategies, states must be explicit about what is expected of professional development and teacher preparedness.
Listening to Latinas: Barriers to High School Graduation
National Women's Law Center and Mexican American Legal Defense and Educational Fund. (2009). Listening to Latinas: barriers to high school graduation. Washington, DC: Author.
Latinas are dropping out of school in alarming numbers. Forty-one percent of Latina students do not graduate with their class in four years—if they graduate at all. Many Latina students face challenges related to poverty, immigration status, limited English proficiency, and damaging gender and ethnic stereotypes. And the high teen pregnancy rate for Latinas — the highest of any ethnic group — reflects and reinforces the barriers they face.
Measures of Change: The Demography and Literacy of Adolescent English Learners
Batalova, J., Fix M., and Murray, J. (2007). Measures of Change: The Demography and Literacy of
Adolescent English Learners—A Report to Carnegie Corporation of New York. Washington, DC: Migration Policy
This report from Carnegie Corporation of New York and the Migration Policy Institute answers the following questions: Who are immigrant students and students who do not speak English well? Where are they from? What is their family background (social, economic, linguistic, etc.)? How well do they do in school? Do their literacy levels prepare them to take part in higher education and a |
Calculating the size of an inferior planet's orbit is fairly easy – we need only one observation. Recall that if an inferior planet is at greatest elongation then the sun, the inferior planet, and the Earth (or other superior planet) are at a right angle. See Figure 1 at right. So measuring the angle of greatest elongation allows us to find the size of the inferior planet's orbit in terms of the size of the Earth's orbit. If θ is the greatest elongation, D is the radius of the Earth's orbit, and d is the radius of the inferior planet's orbit, then
For convenience, astronomers use a unit of distance called an Astronomical Unit, or AU. One AU is the size of the Earth's orbit. Thus we can simplify the above formula to the following:
where d is measured in AUs.
Determining the the size of a superior planet's orbit requires more work. One way to do this is to record the amount of time T it takes for a superior planet to go from opposition to the next quadrature. Then the Earth will sweep out an angle
where E is the sidereal period of the Earth. See Figure 2 at right.
If P is the sidereal period of the superior planet, then it sweeps out an angle
The difference of these two angles gives us the Earth-sun-planet angle at quadrature. Thus, if d is the radius of the superior planet's orbit, then
where d is measured in AUs.
You may have noticed that while we can determine the relative sizes of the planets' orbits using these methods, we don't have enough information to express these distances in more familiar units such as miles or kilometers. Finding the parallax of planets or asteroids is one way in which an observer can determine the size of an AU in more familiar units.
Recall that the synodic period is the period of the phases – that is, the time it takes a planet to return to the same position relative to the sun. The sidereal period is the time a planet takes to complete one orbit with respect to the stars or any fixed frame of reference.
If E is the sidereal period of the earth in days, then the earth moves at a rate of 360°/E degrees per day in its orbit. Likewise if P is the sidereal period of a planet, then the planet moves at a rate of 360°/P degrees per day. Let S be the synodic period of the superior planet.
Copernicus correctly assumed that the more distant planets move more slowly in their orbits. So if we begin with the superior planet in opposition, the earth will have to complete one orbit and then go through an additional angle θ to catch up to the planet. Since the amount of time the earth takes to go though θ is S-E, we have θ=(S-E)×(360°/E). See Figure 3 at right. Since the superior planet also goes through θ in time S we can express θ as S×(360°/P). Equating these two expressions for θ we have
which we can simplify to get Copernicus's result:
For an inferior planet we can just interchange P and E since earth would have the outer orbit. This gives Copernicus's formula for inferior planets: |
Canals and Levees and Everglades Ecology
South Florida’s ecosystem centers on the Everglades. Historically, Lake Okeechobee, Big Cypress, the ridge and slough Everglades, and mangrove coastal swamps were all linked and formed a sheet of shallow water that flowed south across the landscape. Major changes came to the system in the 20th century when canals and levees were dredged and built to combat flooding and provide water for urban and agricultural areas. These drainage efforts substantially lowered the Everglades’s water levels and altered the north to south flow. Today, Everglades management attempts to balance ecology with the needs of south Florida’s agriculture and urban population.
Canals and Levees
Canals have crossed the Everglades since pre-Columbian times, but its modern canals are wider, deeper, and hundreds of kilometers longer than any that existed previously. Because of their size and prominence, canals have shaped and changed the area’s ecology, water movement, and recreational options.
The canal and levee system simultaneously cuts-off and connects the landscape. It can be a barrier to surface water flow and wildfires while increasing nutrient and pollutant spread and retention. In terms of wildlife movement, canals and levees help or hinder depending on the species.
As the amount of research on the Everglades system increases, it is becoming clear that the structure of canals and levees and the division of the landscape have degraded the Everglades ecosystem. In 2000, the U.S. Congress authorized the Comprehensive Everglades Restoration Plan (CERP) to restore natural water flow while also providing water supplies for south Florida’s farms and cities. The CERP has made removing and modifying canals and levees in the Everglades Protection Area (EPA) its central priority. The categories below describe the interaction of the EPA’s ecological and environmental factors with the canal and levee system.
Levees store water during dry periods and prevent flooding over low-lying areas. Canals drain wetlands, which opens land for development and increases water delivery to cities, wells, and the coast. The main effects of canals and levees on Everglades water movement have been:
- Wetlands loss and lowering of water tables
- Reduced freshwater flow and increased salinity in estuaries
- Depletion of natural water storage areas
- Water delivery shift from slow sheet flow to “pulses” through canals
- Low flow pools that are too deep for diverse plant vegetation
- Complete dry-down during the dry season that leads to diminished aquatic habitat and flattening of peat surface
- Canal intrusion into the aquifer and increased salinity and groundwater-surface water interaction
Canals and levees change the Everglades from a relatively stable shallow water environment to fragmented extremes of too wet (deep water) and too dry areas.
Canals deposit nutrient runoff, especially phosphorous, into the wetlands. The natural algae and vegetation mix evolved under nutrient poor conditions, and the increased nutrients are changing plant communities from sawgrass to cattail dominated—this in turn changes oxygen levels and fish populations.
Research of canal sediment and surface water has found pesticides at every sampling site. DDT and methylmercury are among the various herbicides and insecticides.
Canals and levees interrupt and break up the historical continuous wetlands and sheet flow of the Everglades system. Water shaped the Everglades, so changing the flow and availability of water automatically changes the landscape.
The current Everglades landscape does not have the size, seasonal pattern, or habitat variety and connectivity to support its historic populations of wildlife. Dividing the Everglades has degraded the traditional slough-and-ridge and tree-island landscape and blocked environmental processes, such as seasonal flooding and wildfires, from moving through the region.
Canals enable exotic fish species to survive in the Everglades by providing permanent refuges from drought and cold weather. Recent monitoring determined that up to seventy percent of the fish in canals can be nonnative. Canals also act as pathways for the dispersal of invasive snails and clams.
The pest plants water lettuce, hydrilla, and water hyacinth find the deep-water, nutrient-rich habitat they need in Everglades canals. Their dense vegetation outcompetes native plants and also hurts navigation, flood control, and recreation use in the canals.
Levees create upland habitat that allows Australian pine, Brazilian peppertree, and exotic grasses to grow and provides sites for fire ant and Burmese python nests.
Canals as wildlife habitat is a complex topic that is still being researched, but here are some ideas of ways canals change habitats:
Without canals, many species would not be able to move into interior wetlands. Canals open up wetlands not only for exotic species, but also native fish, as canals support movement and range expansion within the region. While both native and exotic fish numbers have increased in canals, the question is how many actually move out of the canals into the wetlands.
There are seasonal changes to wildlife populations in canals. During the dry season, canals and deep water pools serve as refuges for aquatic species, especially predators like bass and alligators. Canals provide either permanent or seasonal habitat for species populations to grow when wetlands conditions are not ideal.
The Everglades bass fishery is a product of the canal system. Canals enhance recreational fishing through the combination of nutrient enrichment, increased prey population during the dry season, and low habitat complexity (which allows predators to be more efficient).
Alligators have moved out of the marshes into canals. These alligators no longer build or maintain alligator holes that provide wetland dry season habitat for fish, amphibians, and bird species. Increased alligator populations in canals also leads to higher predation on prey species, flooded alligator nests along canal shorelines, and adult alligator domination in canals.
Manatees use the canals as alternative habitat sites, especially during winter months when they seek out warmer waters. They often are trapped and killed by locks and water control gates, the second greatest reason for manatee death caused by human activity.
Canals and levees are needed for south Florida’s water management system, but they have had multiple negative effects on the Everglades Protection Area. Removing and modifying these structures (decompartmentalization) in the EPA would benefit the ecosystem by:
- Restoring wetland sheet flow and decreasing rapid canal routing and drainage of water
- Reconnecting wetlands separated by canal and levee barriers
- Eliminating artificial habitats that support and spread introduced plants and animals in the Everglades
The CERP’s restoration plan calls for removing interior canals and levees, while adding more on the periphery of the Everglades. Cooperation of managers and engineers with ecologists and hydrologists will hopefully lead this project in the direction of giving careful consideration to ecological impacts and developing a sustainable method of delivering water.
To view maps and find more detailed information on research sources and proposed system modifications, read the source document Effects of Canals and Levees on Everglades Ecosystems.
Adapted and excerpted from:
Rebecca Harvey, et al, Effects of Canals and Levees on Everglades Ecosystems (WEC304), Wildlife Ecology and Conservation Department (12/2010). |
July 30, 2010, 2:08 p.m.
A mosquito's sweet tooth could help researchers to detect deadly viruses.
Mosquitoes left traces of their saliva, containing viral RNA, on cards soaked in honey.Paul Zborowski
Baiting mosquito traps with cards soaked in honey, and then analysing viral RNA in saliva left by mosquitoes that feed on them, may be a way of tracking the spread of some diseases.
To assess whether mosquito populations are harbouring dangerous viruses, researchers often use traps baited with carbon dioxide or light to attract the insects, which are then ground up and subjected to genetic analyses to identify any viruses. But this procedure does not distinguish between viruses that are safely confined to the mosquitoes' gut and those that have migrated to their salivary glands to be released in saliva when the insects bite a host. An alternative approach is to analyse blood samples from animals, such as chickens and pigs, for antibodies that signal the presence of pathogens. Both methods put people at risk of exposure to the viruses.
Andrew van den Hurk of the Queensland Health Forensic and Scientific Services in Coopers Plains, Australia, and his colleagues have developed a method for collecting mosquito saliva by allowing the insects to feed on honey-drenched cards placed in a trap filled with carbon dioxide. The cards are infused with chemicals that preserve nucleic acids but inactivate viruses, enabling researchers to collect them safely. The team report their new approach in Proceedings of the National Academy of Sciences1.
The researchers infected mosquitoes in the lab with West Nile, Ross River or chikungunya viruses. About 10 days later, they captured more than 90 mosquitoes, placed each one in a separate vial and allowed them to feed on the honey-soaked cards for 2 days. The honey contained blue dye, so that the tint in their gut would later indicate whether the insects had ingested it. The team then used a genetic test to analyse viral RNA on the cards. They found that many mosquitoes had consumed the honey, and that more than 70% of cards tested positive for the three viruses. Almost all cards that mosquitoes had fed on tested positive for the viruses they carried.
The team next tested their approach in the field. Their results showed that traps containing honey-soaked cards attracted more mosquitoes than those without cards, with more than 75% of mosquitoes consuming honey while in the traps. Each week, the team collected cards and trapped mosquitoes and shipped them to a lab, where they were tested for Ross River and Barmah Forest viruses. Viral RNA was found on the cards and in the mosquitoes that fed on the cards.
The approach is promising because it detects viruses only when mosquitoes are capable of transmitting them. Viruses in mosquito saliva can be transmitted, but those in the gut cannot infect a new host when a mosquito bites. But the usefulness of the cards may vary according to the mosquito species and the geographical region, van den Hurk says. For instance, Aedes aegypti, which spreads dengue, chikungunya and yellow fever viruses, prefers blood meals over honey. "The kinds of mosquitoes they trapped with this method are not necessarily the most important vectors for some viruses," says Scott Weaver, who studies virus–mosquito interactions at the University of Texas Medical Branch in Galveston.
The method does not indicate which species, or how many mosquitoes, deposited viruses on the cards. As a result, it would be nearly impossible to quantify the risk of infection on the basis of the amount of viral RNA on the cards, says Phil Lounibos, a medical entomologist at the University of Florida in Vero Beach. "It would be more valuable for the quick and dirty detection of viruses," he says. Once a virus is spotted, he adds, scientists could then use more comprehensive analyses to determine whether the mosquito preys on humans, and to calculate the infection rate in mosquitoes and assess the potential threat.
Next, van den Hurk will compare the sensitivity of the approach with those of other standard methods, such as the use of animals. "At this stage, we really don't want to say that one system is better than another," he says. |
|Turkey Table of Contents
From the time of Atatürk, it has been generally recognized that land reform would speed rural development. Most attention focused on land redistribution--a highly charged political issue. People who favored land reform pointed to the higher yield achieved by owner-operators and attacked absentee landlords. Opponents pointed out that land reform would not solve the difficulties of the rural population because there was insufficient land to establish farms large enough to support families. Whatever the merits of land reform proposals, large landowners effectively blocked most action, and governments often lacked the will to implement those measures that were enacted. Moreover, landless peasants continued to migrate to the cities in sufficient numbers to reduce the pressure for reform.
Historically, Turkey has been a land inhabited by independent peasants. The Ottoman state restricted the growth of a landowning class; and in the early years of Ottoman rule, the central government retained ownership of most of the land, which was leased to farmers under relatively secure tenure arrangements. To maintain farms large enough to support a family and a pair of oxen, the Ottomans exempted land from Muslim inheritance policy, a practice subsequently reversed as the state reinstituted Islamic inheritance practices, sold land to gain revenues, and authorized land transfers. These changes favored the growth of a class of large landowners during the latter decades of the empire. By 1923 landownership had shifted in favor of a small group with large holdings. However, during the republican period land concentration declined, a development that perhaps reflected the effects of division through inheritance or the attraction of alternative investments. At the same time, the opening of new areas to cultivation made land available to those farmers without holdings.
Because no comprehensive cadastral surveys have been carried out, landownership data are still poor in the mid-1990s, but a general picture of ownership patterns emerges. According to the 1980 agricultural census, about 78 percent of the farms consisted of five hectares or less and together accounted for 60 percent of farmland. About 23 percent of the farms were between five and twenty hectares in size, accounting for another 18 percent of the land. Fewer than 4 percent of the farms covered more than twenty hectares, although these occupied more than 15 percent of the farmland. Few farms exceeded 100 hectares. Although experts believed that landownership was more concentrated than data on farm size implied, it was clear that Turkey had more equal distribution of land than did many other developing countries.
Some observers estimate that, despite widespread leasing and sharecropping, a majority of farms are owner operated. However, tenure patterns vary significantly among regions, reflecting different geographical conditions and historical developments. In general, Islamic inheritance practices, which establish set shares for each male and female child, cause fragmented holdings and make leasing and sharecropping extensive. Joint ownership of land is common, and even very small farms normally consist of several noncontiguous plots. Farmers often rent out some of their own land while leasing or sharecropping other plots in order to till areas reasonably close together and large enough to support their families. Owners of small plots may rent out their land and work on other farms or in town. Owners of large holdings, sometimes whole villages, usually rent out all or most of their land. Between one-tenth and one-fifth of farmers lease or sharecrop the land they till, and landless rural families also work as farm laborers.
Tenancy arrangements are many and complex. Some leaseholds can be inherited, but many tenants lack sufficient security to make a long-term commitment to the soil they till. Sharecroppers generally receive about half of the crop, with the owner supplying inputs such as seed and fertilizer. Grazing rights are often held by groups rather than individuals. Many villages have common pastures open to the village herd. Cultivated areas have expanded as individuals appropriate village pastureland to grow grains, a process that not only has caused village strife but also has worsened erosion.
After 1950 the commercialization of agriculture accelerated changes in land-use and tenure patterns. Many of the large holdings on the coastal plains of the Aegean Sea and Mediterranean Sea were converted to modern farms, often benefiting from irrigation projects and specializing in high-value fruits, or industrial crops. Landless families supplied the labor for such modern farms, while sharecroppers and owners of small farms tilled the adjacent land. In these more fertile areas, a five-hectare farm might produce as much income as a twenty-hectare farm in the semiarid central Anatolian Plateau. Southeastern Anatolia, one of the poorest regions of Turkey, included feudal-style landlords who controlled entire villages and many landless families.
Although Atatürk had stressed the need for upper and lower limits on landownership, the latter to halt the fragmentation process, little in the way of effective land reform had been carried out by the early 1990s. Nevertheless, more than 3 million hectares had been distributed to landless farmers between the 1920s and 1970, most of it state land.
The problems of land tenure remain, and some have worsened. Many farms are too small to support a family and too fragmented for efficient cultivation. Tenancy arrangements foster neither long-term soil productivity nor the welfare of tenants. In many areas, the rural poor are becoming poorer while land better suited to grazing continues to be converted to grain fields. At the same time, however, many large landholdings have been turned into productive modern farms that contribute to the country's improved agricultural performance. Major irrigation projects in the Euphrates River Valley and elsewhere offer the prospect of increasing the supply of productive land. The declining population growth rate has reduced the pressure for land reform, and industrialization offers an alternative for landless farm workers, who prefer city life to that of rural areas.
Source: U.S. Library of Congress |
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Teacher Resources by Grade
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|5th - 6th||7th - 8th|
|9th - 10th||11th - 12th|
Color PoemsUsing the Five Senses to Guide Prewriting
|Grades||3 – 5|
|Lesson Plan Type||Standard Lesson|
|Estimated Time||Four 50-minute sessions|
Once students experiment with poetry, they learn that they have another outlet for communicating their thoughts, feelings, and experiences. In this lesson, students are asked to think about colors, while imagining what they taste, feel, smell, sound, and look like. They explore sample color poems, as well as imagery and symbolism. Students use their five senses as a prewriting tool to guide their poetry writing before drafting, revising, and publishing their color poem. This lesson is open-ended enough that students can write free-form poetry or follow a provided template to create a color poem.
Color Poem Assessment: Use this student reproducible to guide peer review, writer review, and teacher review of students' color poems.
Color Poem Templates: This student reproducible contains two templates for writing a color poem.
In "Priming the Pump," JoAnn Portalupi explains "A writer's eye takes in the surroundings with keen perception. Learning to ‘see' means stretching to use all five senses." Portalupi encourages writers to "Stake a claim on something-your desk, the classroom, the lunchroom, your bedroom. Don't just describe what you see, but also include the sounds, smells, and feel of the place" (5). Beyond simply expanding students' perceptions to inform their writing, asking students to include their senses in their writing through metaphor and simile is a powerful way to learn more about their inner thoughts. As Judith W. Steinbergh concludes in her article "Mastering Metaphor through Poetry," "Teachers' guidance in discussing metaphors in literature and in creating metaphor in original writing offers students a powerful tool that supports their intellectual, emotional, and creative development" (331).
Portalupi, JoAnn. "Priming the Pump." School Talk 6.4 (July 2001): 4-5.
Steinbergh, Judith W. "Mastering Metaphor through Poetry." Language Arts 76.4 (March 1999): 324-331. |
Catapult Makers: Rock Stars of Antiquity
for National Geographic News
|February 5, 2004|
Ancient catapults were state-of-the-art weapons of unequalled powerbut how powerful were the military engineers who created them?
"Both the engineers and their achievements were an important part of ancient society," writes Serafina Cuomo, of Imperial College London's Centre for the History of Science. "In antiquity," she added, "catapults not only changed the art of war, but also inaugurated a new era in the relations between political power and technical experts."
Cuomo's recent interpretation, entitled The Sinews of War: Ancient Catapults, is published in the February 6 issue of the journal Science.
Science on the Ancient Battlefield
The making of catapults, known as "belopoietics" (poietike meaning "making of"; belos meaning "projectile or projectile-throwing device") required an ingenious combination of geometry, physics, and technology.
The fearsome machines terrorized battlefields and sieges until the proliferation of gunpowder. Their power was impressive and terrifying. Roman catapults could hurl 60-pound (27-kilogram) boulders some 500 feet (150 meters). Archimedes' machines were said to have been able to throw stones three times as heavy.
The origins of the catapult are unknown. They appear in the historical record as early as a 9th-century B.C. relief from Nimrud in modern-day Iraq.
Early Greek catapults were large bows that included winches able to draw the weapon for firing.
At some point, possibly under Phillip II of Macedonia (382-336 B.C.), father of Alexander the Great, bow arms were replaced by tight bundles of sinew or rope which functioned as "springs."
By the 4th century B.C. catapults were quickly becoming popular throughout the Mediterranean. That technological creep may have stemmed from events like those depicted in a popular ancient story of Dionysiusruler of the Sicilian city of Syracuse.
In 399 B.C., according to the account of Diodorus of Sicily, Dionysius gathered craftsmen from all the cities in his domain. Motivating them with high wages, gifts, and personal praise, he spurred them to construct great numbers and types of weapons. Cuomo describes the strategy as "an inspiring example of policy-driven research."
But was that gathering of top technical minds really responsible for increasing and dispersing knowledge of catapult-building?
Jonathan Roth, an ancient military historian at San Jose State University, finds the idea interesting.
"The catapult is one of the few cases where we think we know something about how ancient technology developed," he said. "It depends what you think of the story of Dionysius and Syracuse.
"The story is interesting and a rare example from antiquity, but we don't really know very much about it. It does seem that torsion artillery, like the catapult, developed at some point and then spread very rapidly. So that kind of story makes some sense in light of what happened. But we just don't know much about these events or peoplenot even about Archimedes."
Archimedes, the legendary mathematician and philosopher, is regarded as one of the ancient world's most prominent military engineers. He's credited with staving off the Roman siege of Syracuse through his ingenious construction and employment of war machinery.
"Archimedes is somebody who might have been very much like the people that Dionysius is said to have brought together," Roth said. "But even though we know much more about him than about almost anyone else whom you might call a type of ancient 'military engineer,' we know virtually nothing about Archimedes. What was his relationship to the state? How did that work? It's very hard to say."
Roth also maintains that much can still be learned on the subject from the types of historical sources examined by Cuomo.
"I do think that there is a tendency to be too critical of the sources and say that ancient people didn't have the concept of thinking about techniques of war in a sophisticated way," he said. "But it does make some sense that the people involved in warfare, which was very significant in the ancient world, knew what their technical problems were and actively looked for solutions to them."
Standards and Subsidies
Cuomo believes that those problems were increasingly addressed by the application of organized scientific knowledge.
Through long experience the ancients identified a basic principle of catapult construction. It stated that all parts of the machine, including the stone or projectile, were proportional to the size of the torsion springs. The establishment of this principle had a dramatic effect.
"Whereas in the old days of trial-and-error, results could never be guaranteed, the introduction of proportionality and thus mathematics allowed catapult construction to be almost standardized," Cuomo writes in Science. "Tables of specification were compiled for quick and easy reference."
Philo of Byzantium (ca. 200 B.C.), in his Belopoietics, promoted using such knowledge for machines that fired long-distance shots, describing such range as something "which they display the greatest enthusiasm over and would exchange anything for." The "they" in Philo's reference is unclear, but Cuomo suggests that it may have been the powerful political figures of the day. Philo goes on to say that technicians in Alexandria were heavily subsidized by ambitious kings who fostered craftsmanship.
Cuomo believes that other governments were not only interested in belopoietics, but financially supportive of the science. "By the end of the 4th century B.C., any state with political aspirations needed a semiprofessional army, any army required machines, and any city had to have a fortified wall," Cuomo writes.
"The rise of advanced catapults, better fortifications, and manuals on artillery and tactics was accompanied by a rise in the visibility and status of engineers, who also worked as architects and surveyors," she says.
In fact, as early as the first century A.D. technology had evolved so far that at least some felt little further improvement was possible. Cuomo cites the Roman Sextus Julius Frontinus' belief that "The invention of [machines of war] has long ago been completed and I don't seen anything surpassing the state of the art."
Technology, of course, has since evolved by leaps and bounds.
"The technologies [the engineers] boasted of may now be obsolete, but their anxieties, their curiosity, and their pride in their knowledge are notperhaps the people behind the machine have not changed that much," says Cuomo.
|© 1996-2008 National Geographic Society. All rights reserved.| |
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. Illustrate the class projects.
When first in public school, Jean often wonders why her projects, executed with equal or better skill than others, are not well accepted by the teachers. Make an illustration that shows a project of hers amidst the projects of the other students, making sure the content of hers makes it stand out. You can do her sewing project, her Easter project, or another of your imagination that is consistent with her style.
2. Illustrate a Biblical scene.
This section contains 1,178 words|
(approx. 4 pages at 300 words per page) |
Ohm's Law also makes intuitive sense if you apply it to the water-and-pipe analogy. If we have a water pump that exerts pressure (voltage) to push water around a "circuit" (current) through a restriction (resistance), we can model how the three variables interrelate. If the resistance to water flow stays the same and the pump pressure increases, the flow rate must also increase.
If the pressure stays the same and the resistance increases (making it more difficult for the water to flow), then the flow rate must decrease:
If the flow rate were to stay the same while the resistance to flow decreased, the required pressure from the pump would necessarily decrease:
As odd as it may seem, the actual mathematical relationship between pressure, flow, and resistance is actually more complex for fluids like water than it is for electrons. If you pursue further studies in physics, you will discover this for yourself. Thankfully for the electronics student, the mathematics of Ohm's Law is very straightforward and simple.
With resistance steady, current follows voltage (an increase in voltage means an increase in current, and vice versa).
With voltage steady, changes in current and resistance are opposite (an increase in current means a decrease in resistance, and vice versa).
With current steady, voltage follows resistance (an increase in resistance means an increase in voltage). |
(a) Batholiths. The largest and deepest intrusive bodies are batholiths, which are the solidified
remnants of magma chambers. Batholiths may be as much as 2,000 kilometers long and 200 kilometers wide, and
they broaden downward to unknown depths. They often serve as the cores of folded mountain ranges.
(b) Dikes. These are tabular bodies of igneous rock formed from the solidification of magma as it
travels upward through fractures in the overlying country rock. Due to the mode of formation, dikes cut across
the structure of adjacent rocks; however, they terminate before reaching the earth's surface. Depending on the
size of the original fracture, the thickness of a dike can range from a few centimeters to over a kilometer, and it
may extend laterally for several kilometers. Dikes are commonly found radiating from a volcanic center, similar
to the way the spokes of a wheel radiate from the hub.
(c) Volcanic Necks or Volcanic Pipes. If the upward movement of magma along a fracture is not
halted at some depth below the surface but is, instead, allowed to continue until lava pours out onto the surface to
form a volcano (see Lesson 1.B.1.b.(1)(a), page 1-12), the tabular intrusive igneous rock body formed is called a
volcanic neck or volcanic pipe. These cylindrical masses may be as much as several thousand meters in diameter.
(d) Sills. A sill is a tabular mass of rock oriented parallel to the bedding planes of the enclosing
country rock. Most sills are connected to a dike system and are formed when the magma, rising along a fracture,
encounters a weak sedimentary layer and subsequently invades that layer. These intrusive bodies rage from a few
centimeters to 1,000 meters in thickness; most are approximately 30 meters thick.
(e) Laccoliths. A laccolith is similar in origin to a sill. It is a large mass of igneous rock formed
along a bedding plane. However, in this case, the magma pushes upward on the overlying rock formations,
creating a domelike structure. The laccolith itself then takes on a lenticular shape.
(2) Intrusive Rock Types. For military purposes, intrusive igneous rocks are grouped into the following
broad categories (see figure 1-2, page 1-5):
(a) Granite. This is the most predominant of the two intrusive igneous rock types and is composed
of essentially light-colored minerals, such as orthoclase and quartz. In fact, it is common practice to apply the
term "granite" to any light-colored, coarse-grained, intrusive igneous rock. Because of its mineral content,
regions composed of granite exhibit a fairly uniform, light-colored tone on aerial photographs, except in areas of
extensive surface roughness, where darker photo tones may be present. In addition, numerous joints, or fractures,
which are represented by dark lines, may produce a "scrabbled" or scratchy photo tone in granitic regions.
(b) Gabbro-Diorite. Gabbro and diorite are actually two different intrusive igneous rock types that
are so similar in appearance that they are often grouped into one category called "gabbro-diorite." Gabbro-diorite
is composed of predominantly dark-colored minerals, such as plagioclase, pyroxene, and hornblende. In the field,
any dark-colored, intrusive igneous rock type is generally referred to as gabbro-diorite. These rock types are
represented by dark photo tones on aerial photographs. |
During tutoring, errors happen all the time and it is critical for tutors to address errors that arise in an appropriate manner. It is always important to point out errors, but to do so in a positive way. Try not to say, “No” or “You’re wrong.” Instead, let them know that they have made an error and encourage them to find out where that error is. If they can self-correct then let them know that they did a good job. If they can’t find the error, make sure to provide enough clues until they discover the errors themselves and reward them for doing so.
Once they have discovered the error that occurred, talk about why they made the mistake and how to avoid it in the future. By discussing each error, students recognize the faulty logic in their thinking and eventually develop much more sophistication when it comes to self-correction. This technique not only helps in the learning process, but gives students more confident in their abilities, because even when they make an error, they still experience success when they correct the error.
In some cases a student may just not understand the question and after providing clues and ample time for the student to self correct, it may be necessary to demonstrate the activity to the student. Be thorough in your explanation of the procedures involved in solving the problem and check for understanding constantly. When you are sure the student grasps how to attack the problem then give them the opportunity to answer a similar question so that they can demonstrate to you that they know how to answer the question.
* All information from this blog post comes from Keith Topping’s article, Tutoring. Educational Practices — Series 5. |
Exercise & Fitness for Children
Parents and other adults can guide children in making healthy food choices and becoming more physically active. One of the best ways to do this is to practice healthy eating and staying physically active as a family.
How will healthy eating and physical activity help my child?
All children need healthy eating and physical activity. Healthy eating and physical activity may help children:
- Build strong bones and muscles.
- Maintain a healthy weight.
- Reduce future chances of developing diabetes and heart disease.
- Feel good about themselves.
How are my child's eating and activity habits formed?
Parents play a big part in shaping children's habits on eating and physical activity. When parents eat foods that are lower in fat and added sugars and high in fiber, children learn to like these foods as well. If your child does not like a new food right away, don't be upset. Children often need to see a new food many times before they will try it.
Parents have an effect on children's physical activity habits as well. See the end of this brochure for resources that can help you and your child. Continue reading to learn about specific actions you can take to help your child develop healthy habits.
A powerful example for your child is to be active yourself. You can set a good example by going for a walk or bike ride instead of watching TV, playing a video game, or surfing the Internet. Playing ball or jumping rope with your children shows them that being active is fun.
Take the time to talk to your children about how a certain food or physical activity may help them. For example, when going for your daily walk, bring your children with you and let them pick the route. Discuss how walking helps you feel better and is a fun way to spend time together. It also offsets calories eaten and inactive time spent in front of TV screens or computers.
Use your children's food choices as teaching moments. Speak up when you see unhealthy eating habits. Direct children to healthier options or say, "You can have a little of that, but not too much." Talk to them about why an overly salty or heavily sugared snack is not the best choice.
You can also praise your children when they choose a healthy item like fruit or yogurt. Use comments like these:
- "Great choice!"
- "You're giving your body what it needs with that snack!"
- "I like those too."
With physical activity, try upbeat phrases like these to keep your child excited:
- "You run so fast, I can hardly keep up!"
- "You are building a strong, healthy heart!"
- "Let's walk 10 more minutes to make us stronger."
What should my child eat?
Just like adults, children need to eat a wide variety of foods. Every 5 years, the U.S. Government releases a set of guidelines on healthy eating (see Resources at the end of this booklet). The guidelines suggest balancing calories with physical activity. The guidelines also recommend improving eating habits to promote health, reduce the risk of disease, and reduce overweight and obesity.
The guidelines encourage Americans ages 2 years and older to eat a variety of healthy foods. Suggested items include the following:
- Fruits, vegetables, unsalted nuts and seeds, and whole grains
- Fat-free or low-fat milk and milk products
- Lean meats, poultry, seafood, beans and peas, soy products, and eggs
The guidelines also suggest reducing salt (sodium), refined grains, added sugars, and solid fats (like lard, butter, and margarine). Added sugars and solid fats often occur in pizzas, sodas, sugar-sweetened drinks, desserts like cookies or cake, and fast foods. These foods are the main sources of high fat and sugar among children and teens.
Another important guideline is to make sure your children eat breakfast to spark the energy they need to focus in school. Not eating breakfast is often linked to overweight and obesity, especially in children and teens. |
Astronomers have detected the first light from planets which orbit other stars.1 This discovery could be called the first direct observation of an extrasolar planet.
In the last ten years, astronomers have detected a number of planets orbiting other stars. Until now, these extrasolar planets have been detected by indirect means. This is because they are far too small and faint compared to their star to be seen directly using standard techniques. However, the extrasolar planets can be detected indirectly.
As a planet orbits, its gravitational pull2 causes the star to wobble slightly. This wobble can be detected on Earth by the slight Doppler shift of the starlight (the light waves are successively stretched out and then compressed as the star moves away and then toward us respectively). The Doppler shift information allows astronomers to determine the orbital period of the planet, and estimate its distance from the star and minimum mass.
In some rare cases, a planet's orbital plane happens to be nearly "edge-on" relative to our position in space. In these cases, the planet travels directly in front of its star once each orbit. This is called a "transit." When the planet transits the star, it blocks a small amount of the star's light; it's essentially a miniature solar eclipse. Astronomers have instruments precise enough to detect this tiny drop in the light from the star. So, even though we can't see the planet, we can see its "shadow." These transit events allow astronomers to deduce additional information about the planet-such as its size. Furthermore, they provide independent confirmation that a planet really is orbiting the star.
Recently, a third independent method has confirmed the existence of two extrasolar planets. Both of these planets were already known to exist from both the Doppler-shift method and the transit method. So, in both cases, the orbital plane of these planets around their respective star is nearly edge-on relative to us. Using the Spitzer Space Telescope, two teams of astronomers (one led by David Charbonneau and the other by Drake Deming) have independently detected infrared light from these two extrasolar planets.3 Infrared light has a wavelength too long to be seen by human eyes. It is reasonable to look for extrasolar planets in the infrared part of the spectrum because the contrast between the planet and star is not as great. The star (while still far brighter than the planet) does not overwhelm the light from the planet in infrared whereas it would in visible light. Both the star and the planet emit infrared, but it is possible to use the edge-on nature of the planets' orbits to distinguish how much infrared light is coming from the planet.
Since these are transiting planets, their orbit carries them directly in front of their star (from our perspective). That means, half an orbit later, they will cross directly behind their star. When this happens, the light from the planet is blocked by the star. It is essentially the opposite of a normal transit event. The total infrared light received from the planet and star drops, since the planet no longer contributes when blocked. The two astronomy teams found that the infrared light dropped just as expected when the planets moved behind their respective stars. This confirms that the planets are real. It is a direct observation in the sense that we are actually seeing light (infrared) from the planet itself, rather than deducing the existence of a planet by the information in the star's light.
These planets, like most extrasolar planets discovered so far, are large Jupiter-mass planets which orbit very close to their star. This is contrary to the original expectations of secular astronomers, who believe that solar systems condense from clouds of hydrogen gas and dust.4 The secular model had been designed to explain how our solar system could form. So, other solar systems were expected to resemble ours, with small terrestrial planets like Earth and Mars orbiting close to their star, and the large Jovian planets orbiting farther out.5 Far from confirming the secular expectations, extrasolar planets continue to support biblical creation. These stellar systems continually remind us of the diversity and creativity that the Lord displayed on Day 4.
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Multicultural York: the Anglo-Saxons (AD400-866)
The Anglo-Saxon period saw enormous changes taking place in York. New settlers from across the North Sea brought a new language, a new religion and a completely different way of life.
This resource uses real and fictional characters to examine how events and individuals helped to shape the modern town.
It describes how the abandoned Roman city was gradually repopulated and how York became known throughout Europe as a centre of Christianity, learning and trade. It can be used for:
History Unit 6B
History Unit 18
Geography Unit 5
Inspiring Learning for All Learning Outcomes:
- Knowledge and Understanding
- Activity, Behaviour and Progression
- Enjoyment, Inspiration and Creativity
- Attitude and Values
See where the North Sea is» |
Nov. 11, 2005 Palmettos in Pennsylvania? Magnolias in Minnesota? The migration of subtropical plants to northern climates may not be too far-fetched if future global warming patterns mirror a monumental shift that took place in the past, new research by an international team of scientists suggests.
The findings, which appear in this week's issue of the journal Science, provide the first evidence that land plants changed drastically during a period of sudden global warming 55 million years ago, said Jonathan Bloch, a University of Florida vertebrate paleontologist and member of the research team.
"It indicates that should we have a period of rapid global warming on that scale today, we might expect very dramatic changes to the biota of the planet, not just the mammals and other vertebrates, but forests also completely changing," said Bloch, who is a curator at the Florida Museum of Natural History on the UF campus.
Scientists have known there was significant turnover in mammals during this rapid period of global warming called the Paleocene-Eocene Thermal Maximum, in which temperatures rose by perhaps as much as 10 degrees in the relatively short time span of 10,000 years, then lasting for another 80,000 to 100,000 years, Bloch said.
Global warming allowed mammals to emigrate across northern land bridges, marking the first appearance of perissodactlys in the form of the earliest known horse; artiodactyls, a group of even-toed ungulates that includes pigs, camels and hippos; as well as modern primates, he said.
But until now, no clues were available as to what happened to plants during this shift, considered one of the most extreme global warming events during the Cenozoic, the "Age of Mammals," Bloch said. "It was very puzzling because it looked like there was nothing going on with plants, which was rather strange and disconcerting."
Excavations by team leader Scott Wing, a paleontologist at the Smithsonian Institution, in the Bighorn Basin of northwestern Wyoming uncovered fossil leaves and pollen alongside fossilized mammals in rocks that were deposited during this turbulent geologic interval.
"Up until this point we have not had a place in which we have mammal and plant remains preserved in the same rocks spanning what we call the Paleocene-Eocene boundary," Bloch said. "Amazingly, these plants came from what would have been more tropical environments."
Some of the plant remains resembled those found in rock deposits of similar age unearthed in Mississippi, Louisiana and Texas, including relatives of poinsettia and sumac, Bloch said.
However, plant fossils found in the same area dating immediately before and after this period of rising temperatures reflected typical mid-latitude forests of the time and included relatives of dawn redwood, alder, sycamore and walnut, Bloch said. As temperatures cooled, floral newcomers appeared from Europe, including species of linden and wing nut. These plants probably emigrated along the same land bridges that animals traveled, he said.
Because his research specialty is mammals, Bloch said he is particularly interested in understanding how the movement of plants affected the earliest evolution of modern primates, which first appeared throughout the world during this period.
"I would very much like to know what these forests were like when these first modern primates were coming in because it has implications for how these animals lived and behaved right from the beginning," he said.
If the landscape evolved from an initially drier habitat, with patchy open spaces, into a more lush tropical forest with densely packed trees, it might have played a role in the evolution of primates' climbing skills, Bloch said. The ancestors of living primates would have been leaping through the tree canopy, foraging for fruit and insects, he said.
Partly because of the dramatic change in mammals, including the first appearance of modern primates, and also because of the interval's rapid temperature change, there has been a wide range of scientific interest in the Paleocene-Eocene boundary, Bloch said.
The warming was caused by a gigantic release of carbon dioxide into the atmosphere that was comparable to the atmospheric effects expected from human burning of fossil fuels, he said.
"You can't predict the future, but there has been a time in the past where we had similar type of conditions, and we might look to that experience," Bloch said.
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|Home > King & civil rights > Background|
The American Civil War (1861-5) put a legal end to slavery and gave black men the vote in 1865. Yet despite this, black Americans were treated as inferior citizens.
In the South, the ‘Jim Crow’ laws, segregation laws that kept blacks and whites apart, controlled the lives of the black population. Black people had to use separate facilities for public transport, housing, hospitals, restaurants and shops. In 1896 separate public schools were ruled to be legal according to the constitution. This separation of facilities was considered acceptable as long as the facilities were equal in quality.
In the Northern states there was not a strict segregation policy. However, black people still experienced discrimination in jobs, education, housing and trade unions.
Few black citizens were able to exercise their right to vote because registered voters had to own property, which many blacks did not. In some states they had to pass a literacy test, which was fixed by white officials. Those who tried to vote were threatened or beaten.
Many black people took a stand over segregation, risking hurt or punishment. Resistance varied.
One of the NAACP’s most significant legal victories came in 1954 with the case of Brown versus the Topeka Board of Education in Kansas. The judgment said that segregation in public schools was unconstitutional. The decision provided a huge spur to the civil rights movement, which started to take ‘direct action’ through non-violent protest to end segregation and discrimination. One such example was the Montgomery bus boycott.
Rosa Parks, who was arrested and jailed for refusing to give up her seat on a bus to a white man, triggered the Montgomery bus boycott led by Martin Luther King. Blacks and whites that disagreed with segregation refused to use the buses and pay fares to the bus companies. The bus boycott lasted over a year. Finally, the Supreme Court said that buses should be desegregated.
The campaign revealed King’s great gift for getting people to work together and his ability as a powerful speaker. It also led to the creation of the church-based Southern Christian Leadership Conference (SCLC), with King as its president, dedicated to co-ordinating non-violent civil rights campaigns around the South.
In the 1960s civil rights protests heated up even more. For example:
President Johnson finally passed the Civil Rights Act in July 1964. It forbade discrimination of all kinds based on race or religion. An Equal Employment Commission was set up.
Campaigners now turned their attention to voting rights. ‘Freedom Summer’ was a big campaign to register black people to vote in 1964. Many civil rights activists, including white students from the North, went to Mississippi. This was the poorest state, where 86% of black families lived in poverty. Activists hoped that the vote would give the black community the means to change their society. CORE led the campaign and other organisations took part. Many campaigners were attacked and threatened and three were murdered. This horrified the nation and gained more support for the movement.
In March 1965, 600 marchers left Selma to walk 54 miles to Montgomery, the state capital, to push for voter registration. When the marchers reached the Edmund Pettus Bridge, police attacked the adults and children with clubs and tear gas. Later Martin Luther King led another march to the same bridge in memory of ‘Bloody Sunday’. Civil rights leaders organised a third march from Selma to Montgomery, this time with federal troops for protection, after James Reeb, a white minister from Boston, was murdered.
Such voter registration drives led to the Voting Rights Act of 1965. Poll tax and literacy tests could no longer be required as qualifications to vote.
Dr King started to plan another march on Washington. It would be called the Poor People’s Campaign for economic equality. He took time out to support the black sanitation workers’ strike in Memphis, Tennessee, in March 1968. On 4 April, Martin Luther King was assassinated. The news shocked the world. There followed riots in 125 cities across the USA. President Johnson signed the Civil Rights Act of 1968 the day after King’s funeral, extending government protection to civil rights workers and making it illegal to discriminate in the sale and rental of housing.
A different kind of black American leader was emerging.
Black leaders sometimes disagreed on the best direction for activism and the civil rights movement, and racial conflicts continued throughout the 1960s. However, one of the most important aims and consequences of the black power movement was to build up pride and strength in black communities.
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There was a time on Earth, about 635 million years ago, when almost the entire planet was covered in ice. At least, this is the idea underlying the Snowball Earth Hypothesis, which holds that there was a massive ice age before the proliferation of complex, multicellular life. Though it's still controversial, geological evidence supports the hypothesis — and suggests that Snowball Earth may have been integral to the formation of an atmosphere friendly to life.
Scientists call it the Marinoan glaciation period. It's an idea that's been around for well over a hundred years, but the theory was revived in 1998 by Paul Hoffman and Dan Schrag.
Their analysis of negative carbon isotope anomalies in prehistoric carbonite rocks suggested that all biological life (namely eukaryotic and prokaryotic life) came to a grinding halt in the oceans for a period of about a million years.
"This collapse can be explained by a global glaciation (that is, a snowball Earth), which ended abruptly when subaerial volcanic outgassing raised atmospheric carbon dioxide to about 350 times the modern level," they wrote. This rapid turn of events, they said, would have resulted in a warming of the snowball Earth to extreme greenhouse conditions.
The resulting phase is known as the Marinoan meltdown.
As the Hoffman and Schrag study suggests, much of the evidence in support of this theory comes in the form of sedimentary deposits that appear to be glacial in origin — deposits that are located at tropical paleolatitudes (i.e. deposits that were located in tropical regions at the time). And indeed, the Earth's landmasses were primarily situated in the tropical regions during the Marinoan.
But not everyone is convinced that volcanic activity was responsible for the Great Thaw.
Writing in Proceedings of the National Academy of Sciences, geologists Huiming Bao and three of his graduate students have put forth an intriguing theory suggesting that it was the Marinoan glaciation period itself that instigated the proceeding greenhouse heat wave. Essentially, the million-year Snowball Earth period resulted in a significant atmospheric shift in carbon dioxide levels — one so dramatic that it hasn't been equalled in geological history.
Under normal circumstances, CO2 levels in the atmosphere are in balance with levels found in the ocean. But Bao suspects that a thick layer of ice could have cut off the connection between water and air, resulting in a dramatic rise in atmospheric CO2 levels. In fact, the authors draw a comparison to modern global warming. As a result, the Snowball Earth created the conditions for extreme changes in atmospheric chemistry that eventually lead to the rapid end of the Marinoan glaciation.
But not only that, it allowed for the conditions suitable for life and the Cambrian Explosion that soon followed. In addition to creating a more temperate climate, the phase also resulted in modern levels of atmospheric oxygen.
Bao and colleagues were able to make this determination by using available radiometric dates from areas near layers of barite deposits (a common mineral deposited in rocks following the Marinoan glaciation). The geologists now call this phase the Marinoan Oxygen-17 Depletion (or MOSD event), a period which may have lasted as long as one million years. The oxygen-17 isotype was critical to their analysis, as only an event like this one could have resulted in the large deviations seen in the normal ratio of O-17 to O-18 (with respect to O-16 isotopes).
"If something unusual happens with the composition of the atmosphere, the oxygen isotope ratios can change," noted co-author Bryan Killingsworth through a statement. "We see a large deviation in this ratio in minerals deposited around 635 million years ago. This occurred during an extremely odd time in atmospheric history."
These findings also demonstrate that the Earth is capable of recovering from severe geological conditions at a rapid pace.
"Mother Earth lived and life carried on even in the most devastating situation," wrote Bao. "The only difference is the life composition afterwards. In other words, whatever humans do to the Earth, life will go on. The only uncertainty is whether humans will still remain part of the life composition."
You can read the entire study at PNAS.
Top image via. |
Louis XIVís domestic policy was to
transform France. Louis XIV built on Louis
XIIIís policy of extending absolute royal rule (centralised
absolutism) to all parts of the kingdom. Louis was the archetypal absolutist
monarch. Aided by politicians such as Jean-Baptiste Colbert, and more
especially, Jules Mazarin, Louis stamped his rule on his kingdom. It was Louis
who had said "L'ťtat, c'est moi." (I am the state) and
few doubted that he meant it.
Louis dominated the central government of France and consulted with hand-picked ministers. On three or four occasions a week, Louis would meet with his Chief Council, the so-called Conseil díen Haut. This consisted of three to five men who were all loyal to the king and hand-picked by him to serve him. Some of the minister who served Louis remain some of the most distinguished in French history. The most prominent were:
Michel Le Tellier
Francois-Michel Le Tellier, Marquis de Louvois
Hughes de Lionne
In the latter parts of Louisís reign, these men were succeeded by men from the same families that allowed for a continuation of policy and loyalty. Those who rose to prominence were career minded men - men of the Robe - and not princes. In fact Louis deliberately excluded the Princes of the Blood and the established nobility in general. He believed that he could best work with men who relied on him for their position in both French society and politics - the educated middle class - and not those who had a history of rebelling against the monarchy.
In previous years, kings of France had used men called Intendants to establish royal power in the provinces. Areas that were remote from Paris, had developed a culture of governing themselves and paying only lip service to royal authority. The role of the Intendants was to change this. The Intendants went, frequently with royal protection, to these remote areas and stamped royal authority on them. Louis XIV realised their importance and extended them in both numbers and functions. Their task was difficult in that they had to overcome a culture in these regions that had existed for centuries - and were frequently feudal in origin. Another group that the Intendants crossed were men who had bought positions in the regions at times when the king had to raise funds. These men were wealthy but frequently ill-equipped to run these offices competently. Their sole purpose was to run them so that they themselves benefited - something Louis would not tolerate. Intendants were used to reform local/regional financial systems, judicial systems and policing the law. In this sense, they trod on the toes of the local nobility in most, if not all, areas of their life. A successful Intendant was suitably rewarded with promotion - this depended on pleasing the king. If an Intendant had done well it was at the expense of the local nobility and to the advantage of Louis XIV.
Louis ensured that the legal system of France was modernised. In fact, what he introduced was used in France to the time of the Napoleonic reforms. Civil law was reformed in 1667; criminal law was reformed in 1670; a Maritime Code was introduced in 1672 and a Commercial Code in 1673.
To enforce his rule, Louis needed a large army. By the time of his death in 1715, the army of France stood at 350,000. Not only was it large in size, but it was also a modern army completely controlled by the state. Such an army ensured that the people were well controlled within France. Any hint of rebellion could be suitably dealt with. The army was answerable to the Secretary of State for War and the Intendants who worked for him. These men all relied on Louis for professional advancement and it served their cause to take on one of the throwbacks to the feudal days of France - local nobles controlling their armies in an independent manner. Their armies were taken over by the state which served a two-fold purpose - it reduced the local power of the nobility and it increased royal absolute power at the same time. To avoid a regional governor becoming too powerful and building up too great an influence in any one region, they were moved from one province to another with a degree of regularity. Their work also became more and more ceremonial as their real work was taken over by Lieutenant-Generals appointed in Paris. By doing this, any chance they had of developing some form of regional power was all but ended.
The credit for finding the modern French Navy went to Jean-Baptiste Colbert. In 1643, at the start of Louis's reign, France had about three serviceable naval boats. For Colbert, this represented a weakness that other nations might exploit. Therefore, a great deal of time and effort went into developing a modern navy. This allowed France to follow an aggressive expansionist policy in both colonisation and commerce. Both added to the wealth and prestige of France.
The economy relatively prospered in the early years of Louis' reign. Under the guidance of Colbert, the French economy did well. Colbert realised the importance of a sound commercial policy and he viewed that overseas trade was the way ahead. France did well in this area and her economy benefited as a result as more tax revenue was raised. However, the fundamental weakness of the French economy was never tackled. Those who could afford to pay the most tax paid the least as a result of out-dated tax clauses and posts bought by the wealthy nobility. Those who could afford to pay the least, proportionately paid the most. Such a system kept many in poverty. Therefore, the greatest number of people were the poor who paid the most tax. This left them with barely enough to live off let alone buy goods that were taxed. Those who had the money to spend were the least in number and their total tax liability would have been completely disproportionate to their wealth. In one sense, the success of Colbert was such that this obvious problem was suitably disguised so that future politicians would have to solve it. |
A crosswind is any wind that has a perpendicular component to the line or direction of travel. In aviation, a crosswind is the component of wind that is blowing across the runway making landings and take-offs more difficult than if the wind were blowing straight down the runway. If a crosswind is strong enough it may exceed an aircraft's crosswind limit and an attempt to land under such conditions could cause structural damage to the aircraft's undercarriage. Crosswind is sometimes abbreviated as X/WIND.
Crosswinds can also be a difficulty when traveling on wet or slippery roads (snow, ice, standing water, etc.), especially with gusting conditions and vehicles that have a large side area such as vans and SUV. This can be dangerous for motorists because of the possible lift force created as well as causing the vehicle to change direction of travel. The safest way for motorists to deal with crosswinds is by reducing their speed to reduce the effect of the lift force and to steer into the direction of the crosswind.
When winds are not parallel to or directly with/against the line of travel, the wind is said to have a crosswind component; that is, it can be separated into two components, a crosswind component and a headwind or tailwind component. A vehicle behaves as though it is directly experiencing a crosswind in the magnitude of the crosswind component only.
The crosswind component is computed by multiplying the wind speed by the sine of the angle between the wind and the direction of travel. For example, a 10-knot wind coming at 45 degrees from either side will have a crosswind component of 10 knots × sin(45°) or approximately 7.07 knots. The headwind component is computed in the same manner, using cosine instead of sine. To determine the crosswind component in real world flight, aviators frequently refer to a chart on which the wind speed and angle are plotted and the crosswind component is read from a reference line. Direction of travel relative to the wind may be left or right, up or down, or oblique; moving non-parallel to the wind's direction creates a crosswind component on the object and thus increasing the apparent wind on the object; such use of cross wind travel is used to advantage by sailing craft, kiteboarding craft, power kiting, etc.
Often smaller aircraft are not limited by their ability to land in a crosswind but their ability to taxi safely prior and post-flight.
Deliberately moving crosswind to increase apparent wind
To increase the apparent wind on an aircraft, sailcraft, or vehicle, move crosswind. |
Atmosphere of the Sun: Photosphere, Chromosphere & Corona
The atmosphere of the sun is composed of several layers, mainly the photosphere, the chromosphere and the corona. It's in these outer layers that the sun's energy, which has bubbled up from the sun's interior layers, is detected as sunlight.
The lowest layer of the sun's atmosphere is the photosphere. It is about 300 miles (500 kilometers) thick. This layer is where the sun's energy is released as light. Because of the distance from the sun to Earth, light reaches our planet in about eight minutes.
The photosphere is marked by bright, bubbling granules of plasma and darker, cooler sunspots, which emerge when the sun's magnetic field breaks through the surface. Sunspots appear to move across the sun's disk. Observing this motion led astronomers to realize that the sun rotates on its axis. Since the sun is a ball of gas with no solid form, different regions rotate at different rates. The sun's equatorial regions rotate in about 24 days, while the polar regions take more than 30 days to make a complete rotation.
The photosphere is also the source of solar flares: tongues of fire that extend hundreds of thousands of miles above the sun's surface. Solar flares produce bursts of X-rays, ultraviolet radiation, electromagnetic radiation and radio waves. [Space Weather: Sunspots, Solar Flares & Coronal Mass Ejections]
The next layer is the chromosphere. The chromosphere emits a reddish glow as super-heated hydrogen burns off. But the red rim can only be seen during a total solar eclipse. At other times, light from the chromosphere is usually too weak to be seen against the brighter photosphere.
The third layer of the sun's atmosphere is the corona. It can only be seen during a total solar eclipse as well. It appears as white streamers or plumes of ionized gas that flow outward into space. Temperatures in the sun's corona can get as high as 3.5 million degrees F (2 million degrees C). As the gases cool, they become the solar wind.
— Tim Sharp, Reference Editor |
for National Geographic News
The yearly light show, created when Earth passes through the rocky debris stream of the comet Swift-Tuttle, is also visible to the six astronauts currently aboard the International Space Station, said meteoroid expert Bill Cooke of NASA's Marshall Space Flight Center in Huntsville, Alabama (comet facts).
Like their earthbound counterparts, astronauts can't see the tiny Perseids until the meteoroids hit the atmosphere and burn up, Cooke said.
From space "they would like look streaks or flashes of light, depending on where the meteorites are relative to the spacecraft," he added.
Cook said he isn't sure whether the view is better from space or right here at home, though the lack of cloud interference would suggest astronauts have a better chance at clear views.
Perseids a Danger to Astronauts?
NASA keeps a close eye on the amount of meteoroids that strike Earth's atmosphere. Even so, the Perseids—each typically a fraction of an inch (about a millimeter) wide—pose no threat to the space station, which is armored with thick metal plates, Cooke said.
Meteor showers in general aren't risky for the space station, Cooke said. For example, the Perseids, which this year have an estimated peak of 80 meteors an hour, elevate Earth's meteor rate only about 5 percent over the average.
But, boasting at least a thousand meteors an hour during their peaks, meteor storms are a different, if rarer, concern.
The next predicted meteor storm should occur on October 8, 2011, during the Draconid meteor storm, Cook said.
Space Shuttle Vulnerable to Meteors
Unlike the space station, NASA's space shuttles are at risk during meteor showers.
That's because the tiny particles are moving at incredibly high speeds—Perseids, for instance, come screaming into Earth's atmosphere at about 37 miles (60 kilometers) a second.
Before every space shuttle launch, Cooke submits a meteor shower forecast to NASA's flight readiness review team.
"That is taken into account in the shuttle risk evaluation, and management decides whether the risk is acceptable or not," Cooke said.
Just in case, NASA tracks nearly all objects that might approach a shuttle. Once in space, a shuttle's only protections are relatively fragile heat tiles and astronauts' fancy maneuvering.
The worst showers are usually avoided altogether, Cooke said. "In general, shuttles do not fly during meteor storms."
SOURCES AND RELATED WEB SITES |
The Korean War
The Cold War between the Communists and the Western Worlds began in earnest at the end of World War II. In order to maintain political prestige among the uncommitted nations of the world, neither side could allow the other any advantage or concession. The Soviets tried to blockade Berlin, and the West answered with the Berlin Airlift (1947-49). In Korea, the armies of both the U.S. and USSR withdrew, but each side armed their respective section of the country. The North Koreans clamored for unification and fomented several armed uprisings in the South in the late 1940s. However, South Korea did not collapse, but grew stronger. This may be why North Korea launched a massive surprise attack against the South on June 25, 1950.
The first year of the Korean War was an incredible seesaw: Seoul (in the middle of the peninsula) changed hands four times. The remaining two years of the war became a brutal bashing of both sides along a heavily defended battle line, whose location changed only slightly from month to month. The final cease-fire line showed no significant gain for either side.
A sequence of 27 maps adapted from the West Point Atlas of American Wars has been assembled here to vividly show the dynamics of battle. The sequence may be viewed as a QuickTime movie.
In brief, the Korean War began with the invasion of the South by North Korean troops. Troops in the South were unprepared and were pushed into a small corner of South Korea in a matter of weeks. The situation was quickly reversed by the first United Nations (UN) offensive in the southeast, coupled with a daring high-tide landing at Inchon near Seoul. The landing forces quickly cut the North Korean supply lines, forcing the now unsupported North Korean armies to flee back north.
The UN armies pressed north of the 38th parallel with the intent to take over North Korea, and the disorganized North Korean army was unable to stop them. A few UN units actually pressed north to the Amnok (Yalu) River, the border between Communist China and Korea. The Chinese warned that they would not accept the conquest of North Korea by the UN and massed for a counter attack. Though less well armed than the UN armies, the Chinese armies were much larger and quickly overwhelmed the UN forces. Some 40,000 U.S. troops were cut off by the advance and evacuated from near Wonsan in mid-December 1950. Seoul was retaken by the Chinese as they pushed south. This time, the Communist forces were stopped about two-thirds of the way down the peninsula. A second UN offensive began in late February 1951, which pushed the Chinese back north of Seoul again. The UN advance stopped near the 38th parallel. A second Chinese offensive was launched in April. Once again, huge waves of Chinese soldiers cut off and destroyed advance UN troops.
This time the Chinese armies stopped north of Seoul. A third UN offensive in May and June of 1951 pushed the Chinese back up near the thirty-eighth parallel again. For the next two years, the war was fought mostly in the air as the battle line on the ground hardened into a massive defensive network on both sides. Incursions on the ground by either side during this time could only be made with great loss of men and little territorial gain. Battle on the ground in Korea was hampered by the extremely rugged terrain. The picture below of an American tank crossing a stream in the central Korean highland in the 1970s gives an idea of how hilly the terrain is and how difficult it was for military maneuvering. Desperate battles in that terrain gave rise to gruesome nicknames for places of bloody fighting like Pork Chop Hill, T-Bone Hill, and Heartbreak Ridge.
The Korean War finally ended in July 1953. Left in its wake were four million military and civilian casualties, including 33,600 American, 16,000 UN allied, 415,000 South Korean, and 520,000 North Korean dead. There were also an estimated 900,000 Chinese casualties. Half of Korea's industry was destroyed and a third of all homes. The disruption of civilian life was almost complete. Try to imagine for a moment what life must have been like for civilians trying to avoid invading armies during the first year of the war when battle lines shifted back and forth through the countryside every few months. Each time opposing armies swept through an area, homes and personal possessions would be damaged or destroyed by shelling or bombing, crops would be trampled, livestock would be stolen for food, and civilians would be harmed by stray gunfire or random violence by individual soldiers. If found, male civilians could be forcefully drafted to fight, and anyone could be accused as being a supporter of the "other" side and then imprisoned or summarily executed.
The result of the Korean War was a stalemate, ending not far from where it began. Was the war a loss for the UN and the United States? Many viewed it as such, even while the war was still being fought. General Douglas MacArthur, World War II hero and commander of the UN forces in Korea, wanted complete victory in Korea and advocated attacking bases inside Communist China that were supporting forces in North Korea. But U.S. President Harry S. Truman and other leaders of the UN forces feared that attacking China would lead to a larger conflict that could easily plunge the entire world into World War III. These leaders felt that the human misery and political humiliation associated with pursuing a limited war was preferable to the much greater loss and doubtful outcome of a global war. As it was, Truman was President and Commander-in-Chief; MacArthur was his subordinate. When MacArthur persisted in his opposition to Truman's political and military objectives, Truman replaced MacArthur with a general willing to pursue a limited war.
The Korean War, the first shooting conflict of the Cold War, remained confined to the Korean peninsula. The fact that it did not expand into a wider war helped confirm the West's policy of containment of Communism, a policy which dominated most international relations during the Cold War. Was containment a misguided policy? On the one hand, it prevented a major war. On the other hand, it led to a seemingly endless string of small, bloody battles all over the world: Cuba, Central Africa, South East Asia, Afghanistan, and many others. Containment also led to massive infusions of economic and military aid by leading nations of both the Communist and Western worlds into developing nations considered to be of strategic importance, while others were bypassed. Repressive political regimes were supported in many poor nations in the name of containment. The debate over containment continued through armed conflicts in the 1960s, nuclear stalemate in the 1970s, and on into the present.
Korea Yesterday ] [ Old Choson Period ] [ The Three Kingdoms ]
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Phonics and spelling in English can be very confusing. It seems like every rule has a host of exceptions that make it tough to know when to use the rule and when the word must be memorised. Vowels can be difficult, and the "ie" combination is one of the many culprits. The pair of letters sometimes makes the long /e/ sound as in "piece." They can be pronounced with a long /i/ sound as in "lie." Both vowels might be voiced as in "prettiest." A few words boast an "ie" that sounds like a short /e/ as in "quotient." Phonics rules can help readers learn to decode the many sounds of "ie."
Teach students to notice the "ie" combination in words. Use a newspaper or other source of text that can be marked. Have the student find and highlight words that have the "ie" combination. Make a list of the "ie" words highlighted for use in later activities.
Have the student sort the "ie" words by the sound made by the letter combination. Put words with "ie" making the long /e/ sound into a group. Group words that have the -ies ending into a category. Put words with "ie" after a /sh/ sound into another group. Subdivide this category into words with "ie" following "c" (efficient) and "ie" following "t" (patient) if you wish. Create one more group for words with both vowels voiced, as in "shaggiest."
Examine the words in each group for patterns. For example, the words ending with "-ies" have a long /e/ sound when a "y" has been changed to "i" for a plural ending. Words that were spelt with an "ie" originally (such as "lie" or "die") have a long /i/ sound. Words that have a "t" or a "c" before the "ie" pair usually have a /sh/ sound and a short /e/ sound instead of the long /e/ sound typically made by "ie." The words with both vowels voiced separate the "i" and the "e" into different syllables. This is usually caused by adding a suffix beginning with an "e" onto a word ending in a "y" that has been changed to an "i."
Assess the student's understanding of the "ie" phonics pattern by using nonsense syllables. Letter clusters such as "iester," "shackies," "extentient" and "nies" can be decoded using the related "ie" phonics rules. The nonsense word "iester" should be pronounced "eester" because "ie" is generally pronounced as a long /e/. The nonsense word "shackies" should be pronounced as "shack-ees" because of the rule about changing "y" to "i" and adding "es." "Extentient" would be pronounced as "ex-ten-shent" because the "ie" combination following a "t" creates a /sh/ sound followed by a short /e/ sound.
Assess the reader's application of the rules about "ie" by allowing the student to read orally from a contrived text containing many different kinds of "ie" words. Note which words are read successfully and which are misread. Plan review activities to reteach concepts that are not yet internalised. |
The American civil war was the largest ever armed conflict to occur on America's soil and it occurred in between the years of 1861 to 1865. It was deadly and arguably the most important event in the nation's history. Sections entrenched in the constitution of the united sates Catapulted tension between the northern and the southern states leading to a brutal war. Slavery was a root cause of the conflict. This war increased America's economic dominance until it overtook all the other countries of the world. It also lead the country into having a strong constitution that made Americans to be part of a single nation instead of a corporate made up of different states with their own rules and institutions. The war indeed changed the way Americans viewed their own nation seeing it as one nation. After the war every part of America's national fabric changed; from the role of the federal government to the status of African Americans. The war was triggered by the victory of Abraham Lincoln in the elections of 1860.
FACTORS THAT MADE THE CIVIL WAR IRREPRESSIBLE
In these elections. The Republican Party led by Lincoln won, beating three other candidates. The southerners did not vote for him so his victory was seen as a northern affair. His speech, given in 1858, stated that, a divided house cannot stand and visualized that America can not endure a “half-slave and half-free.” This clearly showed that he was a moderate and was therefore not up to task, in the views of the southerners, to be able to tackle the abolitionist they perceived as a threat. He countered this by stating he will uphold the doctrine of states right. Most southerners distrusted him.. His victory in the election led to the secession of eleven southern states from the union leading to the formation of the Confederate States of America with Jefferson Davis as its president. This was viewed by the US administrators as an act of treason.
Hostilities were prompted in April of 1861 when the... |
An Illyrian of low birth, Diocles rose through the ranks to the consulship. He was chosen by the Army in 284 to replace Numerian and after the assassination of Carinus became sole ruler of the Roman Empire. He changed his name to Diocletian upon his ascension.
Diocletian felt that the system of Roman imperial government was unsustainable in the face of internal pressures and a military threat on two fronts. He gave Maximian the title of Caesar, which was the traditional form in which an emperor (Augustus) designated a successor. However, Diocletian soon made Maximian an Augustus as well. The imperial power was now divided between two people. Diocletian's sphere of influence was the east, and Maximian's the west.
The two men established separate capitals, neither of which was at Rome. The ancient capital was too far removed from the places where the empire's fate was decided by force of arms. While improving the ability of the two emperors to rule the empire, the division of power further marginalized the Senate, which remained in Rome.
In 292, Diocletian and Maximian each appointed a Caesar (Galerius and Constantius, respectively). However, these were not merely successors - each was given authority over roughly a quarter of the empire. This form of government is known to historians as the Tetrarchy.
Considering that during the half-century preceding Diocletian's ascension the empire had been in a constant state of simmering civil war, with (according to one scholar) a new emperor every two and a half years on average, it is remarkable that the Tetrarchy did not immediately fall apart due to the greed of any one of the four emperors. The opportunistic nature of Roman imperial politics did eventually cause the disintegration of the Tetrarchy and the reinstitution of one-man rule, but this was not until the 320s.
In 305, Diocletian retired to his palace at the administrative center of Salona on the Adriatic Sea, near the modern Split, Croatia. He was the only Roman emperor to remove himself from office; all of the others either died of natural causes or were removed by force.
The last and greatest persecution of Christians by the Roman Empire was carried out during his reign, though Galerius carried it out more avidly than Diocletian himself.
|Oriens||Libya, Egypt, Plaestine, Syria, and Cilicia|
|Pontus||Cappadocia, Armenia Minor, Galatia, Bithynia|
|Asia (Asiana)||Asia, Phrygia, Pisidia, Lycia, Liydia, Caria|
|Thrace Moesiae||Moesia Inferior, Thrace|
|Moesiae||Moesia Superior, Dacia, Epirus, Macedonia, Thessaly, Achaea, Dardania|
|Africa||Tripolitana, Africa Proconsularis, Numidia, part of Mauretania|
|Hispanie||Mauretania Tingitana, Baetica, Lusitania, Tarraconensis|
|Viennensis||Narbonensis, Aquitania, Viennensis, Alpes Maritime|
|Galliae||Lugdunensis, Germania Superior, Germainia Inferior, Belgica|
|Italia||Liguria, Venetia, Alpes Cottiae, Alpes Graiae, Raetia|
|Pannoniae||Pannonia Inferior, Pannonia Superior, Noricum, Dalmatia|
|Suburbicaria||Umbria, Campania, Sicilia, Corsica, Sardina| |
A social system that florished during the Medieval period, and began to decline shortly thereafter. The system was organized around an aristocracy, headed by a king. Each noble controlled territory (and its inhabitants) placed under the noble's control by the king. In return for this land, and the revenue it generated, the nobles were obligated to maintain soldiers for the king's service. In practice, feudalism was a hodge-podge of rights and obligations, which was eventually dismantled by the kings themselves in favor of central government and fewer independent minded nobles. A professional army in the pay of the king was also found to be more reliable. Feudalism was not confined to Christendom, but was also common in many Islamic lands, and places even further afield, such as India, China, and Japan. |
This is one in a series of vignettes celebrating Kansas history. The series’ name comes from the state motto, Ad astra per aspera: To the stars through difficulties.
It is hard to know Kansas without understanding the impact the Homestead Act of 1862 had on the state’s settlement.
This year marks the 150th anniversary of the act, which President Lincoln signed “so that every poor man may have a home.”
It has been called one of the most important pieces of legislation in the United States. From it, Kansas gained its diverse roots.
To acquire land under the act, a person had to pay a $10 filing fee, live on the land for five years, and cultivate and improve it. On the treeless plains of Kansas, families built dugouts and sod houses and strung miles of barbed wire, some using limestone posts hewn from native stone to string the wire.
They also broke the prairie sod with their plows as they laid out the neat squares of land that became farms and townships.
The most notable homesteaders included the following groups:
• Jewish farmers who built enclaves in a half-dozen settlements near Dodge City.
• Exodusters — former slaves from the South — who flocked to western Kansas to start farming communities. Nicodemus is the last remaining all-black community to survive.
• Volga Germans from Russia who built Catholic strongholds near Hays.
• The Swedes who settled what became Lindsborg.
• Mennonites who settled here from Russia.
Some of the most famous homesteaders included the Ingalls family, who homesteaded near Independence. Laura Ingalls Wilder was in her mid-60s when she began writing down her childhood experiences, which were published as the “Little House” series.
"There was only the enormous, empty prairie, with grasses blowing in waves of light and shadow across it, and the great blue sky above it … In all that space of land and sky stood the lonely, small, covered wagon,” Ingalls wrote.
Kansas, as a homesteading state, had nearly 90,000 successful homestead claims, representing 25 percent of the state’s total acreage. Immigrants, Civil War veterans, women and former slaves all came out of a sense of starting over.
Some walked. Some came by covered wagon. Others rode on trains.
Some of the first land offices in western Kansas — in Larned and Hays — recorded thousands of acres and entries. In 1877, Hays had 31,895 acres in homestead entries; Larned 145,878 acres.
In his book “West of Wichita,” Kansas historian Craig Miner told of one prospective homesteader headed to western Kansas by train. He was asked where he was going.
“Hell,” he replied.
The conductor said, “That’s 65 cents and get off at Dodge.” |
Fire shapes global vegetation
A world that never burned would contain twice as much forest.
An area's temperature and rainfall have always been thought of as key to which plants grow there, to whether it becomes grassland, savanna or forest. But fire may have the biggest influence on the global distribution of vegetation, report researchers from South Africa and Britain.
In a fire-free world, forest cover would double at the expense of grasslands and savannas say William Bond of the University of Cape Town and his colleagues in the journal New Phytologist1. The team used a computer model to predict how plant patterns shift over time with changing climates.
For example, a type of grassland consisting of warmth-loving plants appeared in the tropics between 6 million and 8 million years ago, and quickly spread around the globe. This study suggests that the grassland's spread was primarily influenced by fire, says Bond, although it is not known why there were more fires at that time.
"Fire is more than an unnecessary evil," says team member Ian Woodward, an ecologist at the University of Sheffield, UK. Without fire, forests would leap from forming 26% of the world's vegetation to 56%, reports the team. Tropical grasslands and savannas, such as those in South America and Africa would shrink to half their current extent; temperate grassland and Mediterranean shrubland would be reduced by nearly two-thirds.
"Fire is grossly under-evaluated in terms of its global impact on ecosystems," says Jon Keeley, an ecologist with the US Geological Survey's Western Ecological Research Center in California. "Anybody who looks at the global picture will be very surprised," he adds.
For years, US policy was to extinguish every fire on public lands. But in August 2000, government agencies developed the National Fire Plan, which recognizes that wildfires play an important role in maintaining certain ecosystems.
Fire control in the United States is fraught with controversy, however, because communities are still being built on fire-prone lands. Spectacular and destructive wildfires are a regular feature of the American summer. In 2004, for example, Alaska experienced its worst fire season on record: more than 6 million acres of land burned in 700 fires across the state.
But, says Bond, "If we try and switch fire off, we would be losing ecosystems that have been around for millions of years. These natural ecosystems are dependent on burning, and have to be actively managed."
- Bond W. J., Woodward F. I. & Midgley G. F. New Phytologist 165, 525-538 (2005). doi:10.1111/j.1469-8137.2004.01252.x
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Regulator clocks, sometimes referred to as pendulum clocks, were invented in the late 18th century in a quest for greater timekeeping accuracy. They were weight-driven devices and featured a deadbeat escapement (an improvement on the anchor design). To ensure their accuracy, they usually omitted complicated features like calendars. Instead, each of the clock’s hands worked off a different mechanism.
The Englishmen Benjamin Vulliamy and James Harrison invented two of the earliest regulators between 1760 and 1780. Despite this British lineage, regulator clocks were not especially well received in England, but they were in Vienna, where the form flourished. Indeed, Vienna regulator wall clocks gained such a reputation for accuracy that they were routinely used in public places such as railway stations and post offices.
During the Empire period (1800-1835), the cases of early Viennese regulator wall clocks were typically made of wood, which was either polished or gilded. These laterndluhr clocks resembled three boxes, one stacked on top of the other. The upper part of the case housed the movement and was capped by a roof. The clock’s weights dangled in the center of the case, and at the bottom swung the pendulum...
The Biedermeier period (1835-1848) was a very conservative time in Vienna—regulator clocks reflected the new austerity. The dachluhr clocks from this era were thus simpler in style. Instead of three sections, these clocks had two: a top section (still with a roof) for the clock’s face and movement, and a bottom section for the weights and pendulum, which could be accessed by a glass door. The clocks were elegant but rigid in their design, except for the "piecrust" bezels around the clocks’ faces.
The Viennese revolution of 1848 expanded the middle class, which made luxuries like regulators more accessible to a greater percentage of the population. And after years of aesthetic repression, these newly affluent Viennese embraced revivals of Greek, Renaissance, and Gothic styles.
For regulator clocks, this meant that straight sides would give way to serpentine waves. Ornamentation was on the rise, as pediments were interrupted by finials and the sides of regulators were ornately carved and scrolled. As for the dials, they were rendered in creamy, bright porcelain.
In 1850s Vienna, antique regulator clocks continued to become increasingly ornate. This meant more finials, more flanking columns, and fancier woodwork on the clock’s top and bottom—walnut, cherry, and other veneers replaced the faux-grain finishes that had come before. Inside the clock, the movement had hardly changed, but pendulum rods were now made of wood and the bezels around the porcelain dials were eye-catching rings of brass.
The Vienna regulator clocks from about 1870 to 1895 are the most common today. They are also some of the most ornate and beautiful. Signatures of these regulators include the Corinthian columns on the sides of the cases and the clock’s elaborate hands.
All that effusive design ground to a halt at the turn of the 20th century, when the overlapping impulses of Art Nouveau and Arts and Crafts ushered in the Jugendstil style, which was a precursor of sorts to 20th-century modernism. It was a return to the box regulators of almost a century before, but this time the lines were softer, the boxes were less boxy but more massive. In addition, Viennese regulators from this period often featured leaded and beveled glass in front of their swinging pendulums, and the woods ranged from gorgeous maple to rich walnut.
In the United States, 19th century clock manufacturers such as Ingraham, Sessions, Seth Thomas, and New Haven also made regulators. Some were designed like squat versions of the famous banjo clocks that were so popular, others were marketed as "railroad regulators" with train-station style numerals and hands.
Just as in Vienna, accuracy was the main selling point for makers of U.S. regulators. Even more interesting, the look of these U.S. clocks paralleled the evolving design of those of the old country, which suggests that U.S. clockmakers were not yet setting the standards for clock design.
Key terms for Antique Regulator Clocks:
Escapement: A device that converts the pressure of a spring or coil into a fixed release of movement.
Interviews & Articles
How did I get interested in clocks? Something about them has always been ingrained in me. My mom’s father had a small collection o… [more]
I was working as a jewelry department manager for a department store, and I had a customer who brought a clock in for repair. I wa… [more]
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Banishing those accursed spikeselectronicsfeed.com, May 29th
It consists of relatively low frequency ripple at the switching regulator's clock frequency, typically 100kHz to 3MHz, and very high frequency content “spikes” associated with power switch transition times. The switching regulator's pulsed energy...Read more |
The steady and dramatic Arctic sea ice that has been recorded in the last three decades has become a topic of great interest to the media and people in general, as it can be seen as a clear sign of global warming. However, the other side of the world, something more complex is going on, to the point of generating an apparent contradiction that seems to give them reason to climate change skeptics.
A new study, conducted by the team of climatologist Claire Parkinson, of Goddard Space Flight Center of NASA, Greenbelt, Maryland, shows that from 1978 to 2010, the total area of sea ice around Antarctica grew to approximately 6,600 square miles each year on average. Considering the results of a previous study by the same authors, this growth rate has accelerated recently, as the average between 1978 and 2006 was less than 4,300 square miles per year.
However, this enigmatic phenomenon which seems to contradict the perceived reality of global warming, has an explanation.
Earth’s poles have very different geographies. The Arctic Ocean is surrounded by North America, Greenland and Eurasia. These large masses catch most sea ice annual cycle of freezing and thawing. But a large fraction of the oldest Arctic ice is gone and thicker over the past three decades. The summer ice cover is shrinking and left exposed to direct sunlight into the dark ocean water, which absorbs more sunlight than ice, which causes it to heat up even more and cause further contribute to ice losses.
At the opposite end of the planet, Antarctica is a continent surrounded by open sea, allowing the sea ice expands in the winter, but also offers less protection from the sun during the melting season. Nevertheless, the total extent of sea ice surrounding Antarctica has tended to increase in recent years, as mentioned.
Parkinson and Don Cavalieri, of the NASA center believe that this pattern contrasted ice cycle could be due to changes in atmospheric circulation. Recent studies point to the weakening of the ozone layer over the South Pole as a possible cause. Ozone retains solar energy that would otherwise be lost. Because of this, the lowest concentration over Antarctica can cause a cooling of the stratosphere (the layer of the atmosphere which is at an altitude of between 10 and 50 kilometers (6 to 30 miles). Meanwhile, the temperate latitudes have been warming, and the temperature gradient has strengthened circumpolar winds that blow over the Ross Ice Sheet.
So, those winds acting on the Ross Ice Sheet are growing stronger, and that causes the sea ice is pushed offshore, causing the appearance of sea areas near the coast and devoid of ice. The larger coastal areas devoid of ice, new ice will be generated, because in these areas the water is in direct contact with the cold winter atmosphere and freezes quickly. Therefore, as explained Josefino Comiso of NASA’s Goddard Space Flight, as the wind keeps blowing, the northernmost ice can be extended.
However, it is important to understand that in the Arctic Sea ice is lost much of the gains in the Southern Ocean. The extent of the ice cover of the Arctic Ocean in September 2012 was 1.32 million square miles less than the average extent from 1979 to September 2000. The area of ice lost roughly equivalent to that occupied by two Alaskas.
As Parkinson underlines the fact that some areas of the Southern Ocean are cooling and producing more sea ice does not prove that global warming is a false perception. “The weather does not change uniformly. Earth is very large and the expectations are certainly different changes are recorded in different regions of the world,” said Parkinson. |
Earthquakes- an Introduction
- This lesson explores what earthquakes are, in the context of plate tectonics, by demonstrating what occurs along a fault line during an earthquake.
- Bubblegum (for engagement activity)
- chewing gum won’t work here, as you are attempting to blow a large bubble
- Wooden blocks with sandpaper pasted on, or sanding blocks
- Students will be able to understand and describe how an earthquake occurs in terms of plate tectonics (faults, plate boundaries, and plate movements).
- Students will be able to diagram the movement of two plates, relative to each other, during an earthquake.
National Standards Addressed
- Math (Presented by National Council of Teachers of Mathematics in 2000)
- Problem Solving
- Solve problems that arise in mathematics and in other contexts
- Use representations to model and interpret physical, social, and mathematical phenomena
- Science (Presented by National Research Council in 1996)
- Physical Science
- Motions and forces
- Properties and changes of properties in matter
- Transfer of energy
- Science and Technology
- Abilities of technological design
- Earth and Space Science
- Structure of the Earth System
- Earth’s history
- Technology (Presented by the International Society for Technology in Education in 1998)
- Technology research tools
- Students use technology to locate, evaluate, and collect information from a variety of sources.
Engagement Activity (optional)
- Place a piece of bubblegum in your mouth, (or use a student volunteer). Blow a bubble, slowly, until it pops. Ask the students why the bubble pops.
(Continue to demonstrate, as necessary).
- Discuss the fact that the bubble pops because the surface of the bubblegum gets thinner and thinner and the air pressure in it causes it to burst when the gum can no longer contain the air. When a bubble pops, the pressure that has been building up releases, abruptly.
- The activity handout will instruct the students to take a wood block (which represents a continental plate) in each hand and firmly press them together.
This will represent the pressure of two plates pushing against each other.
- The students will then be instructed to maintain this pressure while simultaneously starting to pull one block toward them and push the other block away
from them. As they begin to increase the force on the wood blocks both toward and away from themselves (all while firmly pressing the blocks together)
they will reach a point where the two blocks slip and suddenly slide across one another.
- Arrows that line up when the blocks are in their original position will allow the students to see how the “plates” have moved in relation to each other.
This sudden slide is contrary to the normally slow, steady movement that they have been told plate tectonics usually exhibits. This sudden thrust is due
to the build up of pressure along the plate boundary.
- The students will be asked to repeat the activity using the wood blocks. Throughout the activity they will be asked to record their observations and make
inferences based on what they see and what they know about plate tectonics.
- Divide students into groups of two or three (depending on class size and available materials).
- Provide each group with a handout for the activity and briefly explain what they will be doing.
- As the students complete the activity they will be asked to record their observations and make inferences about what the observations mean relative to
plate movements and the resulting effects.
Sustaining, Concluding, or Extending Activities (optional)
- Students will then discuss in their small groups and as a whole class what this means on a larger scale. If those blocks represent two large continental
plates, what is happening when they abruptly slide past each other?
- Using available online maps of the plate boundaries, have students discuss the likelihood of an earthquake occurring in their area.
Evaluation and Assessment
- Explain what an earthquake is and how it is caused (in the context of plate tectonics).
- Include a diagram of a fault or plate boundary in the above explanation as a means of further demonstrating their understanding of earthquakes.
E-Resources, Print Materials, and Hands-on Activities |
Science Fair Project Encyclopedia
Treaty of Troyes
Signed in 1420, it disinherited the legitimate heir to the French throne and proclaimed Henry V the successor to the French king, Charles VI. It was designed to end the Hundred Years War which began in 1337. By the time it was signed, Henry V of England had undergone a successful campaign to take control of Northern France (1415-1419), and had concluded an alliance with the Burgundians who controlled Paris. Charles VI, who many believed had gone mad, agreed to have his daughter Catherine of Valois marry Henry V, insuring Henry V's legitimacy to the thrown of France. The agreement was eventually ratified by the Estates-General of France later in the year after Henry V entered Paris. Worse, for France at least, the queen, Isabeau of Bavaria, claimed that her son, Charles, was actually the result of an affair, and thus could not be the legitimate heir of Charles VI. When Henry and Charles died within months of one another in 1422, the infant son of Henry V, Henry VI, was proclaimed, in Paris, to be king of both France and England. Henry VI of England ruled Northern France through a regent, while Charles VI's son, Charles VII, reigned only in Southern France from his stronghold in Chinon. Eventually, the treaty failed when Joan of Arc began her mission to crown Charles VII of France, and begin drive the English finally out of the kingdom. Even after Charles VII succeeded in reconquering France, the English would continue to claim rightful ownership of the French crown for centuries..
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 |
NGC 5548: A spiral galaxy located in the constellation Boötes, of a type known as a "Seyfert galaxy" because of the intense energetic activity produced by its central region.
Caption: This X-ray spectrum taken by NASA’s Chandra X-ray Observatory shows details of the energy radiated by the hot gas located around the galaxy's central giant black hole. In what amounts to a cosmic bar code, this spectrum allows scientists to take an inventory of elements, such as carbon, nitrogen, and oxygen that are present in the multimillion degree gas. It also reveals that some of the hot gas is flowing away from the black hole, probably because of the enormous amount of energy that is being radiated by the extremely hot gas very near the black hole.
Chandra X-ray Observatory LETG /HRC Image |
The icosahedron is a 20-sided polyhedron with each side made up of an equilateral triangle.
Each vertex is formed by joining five triangle faces together. Ancient Greeks discovered
that certain solid objects could be made from flat polygons such as the equilateral
triangle and square. A tetrahedron is made from 4 triangles, a cube from six squares,
an octahedron from 8 triangles, a dodecahedron from 12 pentagons and the icosahedron
from 20 triangles. As the number of faces increases in the
polyhedron, its shape becomes more spherical.
Each face of the planetary Icosahedron displays a part of the (nearly spherical) planetary surfaces. The triangles are folded so that adjacent triangles are joined exactly at their closest edges. The cut-out pattern forms the complete globe with the North and South Poles at opposite vertices. The overall size of an assembled globe is approximately 2.75 inches if printed on an 8 1/2 x 11 piece of paper and 3.75 inches if printed on an 8 1/2 x 14 page.
To assemble the icoshedron cut along the edges of the map. You can use tape or glue to assemble the globe. Double-sided tape works well. The challenge is in connecting the last edges together. Good luck and have fun.
All of these icosahedrons are © copyrighted 1998-2002 by Calvin J. Hamilton. Permission is granted for teachers to use the planetary icosahedron in classroom activities. Teachers may make copies for their students as long as the copies are given freely to them. Under no circumstance may the icosahedrons be used for-profit or commercial use without contacting Calvin J. Hamilton. The Idea for creating this page was by A. Tayfun Oner.
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© Copyright 2002 Calvin J. Hamilton. All rights reserved. |
Health workers have called the Ebola outbreak in West Africa unprecedented, overwhelming and even out of control.
With 844 cases so far, it's the largest and deadliest outbreak since the virus was discovered in 1976. And it doesn't show signs of slowing down. On Tuesday, the World Health Organization reported 50 new cases in Liberia and Sierra Leone. Despite the current crisis, however, the likelihood of the virus's spreading beyond Africa is very low.
Here's what we know about this painful and deadly disease.
What is it? A nasty, often fatal form of hemorrhagic fever that gets its name from a river in the Democratic Republic of Congo. That's where Ebola was first detected, in a nearby village.
There are five different species of Ebola, each named after where it was first found. Sudan, Bundibugyo (named after a Ugandan district) and Zaire viruses have all been linked to outbreaks in Africa. The Tai Forest virus, found in the Ivory Coast, has only caused one documented case — a scientist who caught it from sick chimpanzees in 1994.
The fifth species is Reston, named after the D.C. suburb of Reston, Va. Yes, that's right: Ebola was found in Virginia, but just in monkeys. They had been shipped from the Philippines to a Reston laboratory.
So far, there have been no documented outbreaks of Ebola Reston in humans.
Symptoms: It can take anywhere from two to 21 days after infection for symptoms to kick in, but once they do, the pain is excruciating. It starts off with a fever, muscle pains, vomiting and diarrhea. It also makes the victims so weak that it leaves them bedridden. As the virus spreads, it can shut down major organs, such as the kidneys and liver. And the infection can cause internal and external bleeding from openings in the body, including eyes, ears, nose, rectum and even pores. The peak of the illness is the first seven to 10 days, during which patients are most likely to die.
How often does it kill somebody? Each Ebola species is associated with a specific mortality rate.
Health workers are currently battling the deadliest one, Zaire, which can kill up to 90 percent of people infected.
So far in this outbreak, there have been 518 deaths. That puts the current mortality rate at about 60 percent. This improvement is most likely because health workers are better at giving supportive care to patients, like nutrition and fluids, which may help their immune systems fight the virus. Health workers also track down those infected, or likely infected, more quickly. So supportive care can start earlier.
How does it spread? Through close contact with infected blood, saliva, urine and stool.
In previous outbreaks, researchers have found that the virus initially spread to people from infected monkeys, which are hunted and eaten in parts of rural Central Africa. Some scientists also think that bats are the initial source of the virus.
Health care workers and family members can catch Ebola by caring for the sick. An infected person remains contagious even after death. So family members can also be infected while preparing a body for burial.
Where does it live? The illness mostly crops up in remote villages of Central Africa, with outbreaks in South Sudan, Democratic Republic of Congo and Gabon. There have also been outbreaks in Uganda in 2000, late 2007 and 2012.
This year marks the first Ebola outbreak in West Africa. The WHO reported the first confirmed cases in Guinea back in March, although some officials say people may have been infected in late 2013. The virus then rapidly spread to the neighboring countries of Liberia and Sierra Leone.
What's fueling the current outbreak? A few things. The virus has struck densely populated cities, such as Conakry, Guinea, and Monrovia, Liberia. Cases have cropped up in 60 hot spots across a large swath of land.
Since the disease is new to the region, many people aren't aware of how Ebola is transmitted. And the resources devoted to stopping the outbreak have been limited. Last week, the WHO said more money, people and attention were needed to keep the virus from spreading to more countries.
Vaccine and cure: None. But some small companies have already started looking. They have come up with a few treatments that show promise in animals and are looking to test them in people as early as next year.
Infected patients are quarantined in isolation wards to prevent spreading the virus.
Doctors closely monitor to see if symptoms fade and whether the body has produced antibodies to fight off the infection — usually a hopeful sign for a full recovery.
Patients are declared Ebola-free if they don't show any symptoms for several days and if repeated tests for the virus in their bloodstreams come back negative. (The virus can still linger in semen for months and for a shorter time in breast milk, as the antibodies don't reach those areas. Men who recover are given condoms; mothers are told to wean their children.)
In many cases, the virus weakens the body so much that patients have to stay in the clinic days after they're declared virus-free.
What happens to Ebola survivors? Suffering through Ebola is a traumatic experience in itself. Returning home from an isolation ward can also be a challenge.
Ebola survivors are likely to be shunned and isolated by their communities. Many people still think survivors are contagious. This is where education and grand gestures from health care workers — a big kiss on the patient's cheek — can help to mitigate the stigma. |
Trojan asteroids, asteroids that revolve about the sun in the same orbit as a planet, occupying stable positions (known as Lagrangian points) either about 60° ahead of the planet in the orbit or about 60° behind it. Such asteroids were first discovered (1906) in Jupiter's orbit. In 1990, a similar asteroid, Eureka, was found in the orbit of Mars, and several others have since been discovered. Similar asteroids also have been found in Neptune's orbit since 2001, and a Trojan asteroid in earth's orbit was confirmed in 2011.
The Trojan asteroids represent one possible special solution to the famous three-body problem (see also celestial mechanics), with each group forming an equilateral triangle with the planet whose orbit they share and the sun. Some Trojan asteroids are composed of ice and dirt, rather than rock, making it possible that they are captured comets. The first Trojan asteroid discovered was Achilles, observed by the German astronomer Max Wolf; all of Jupiter's Trojan asteroids are named for heroes of the Trojan War.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved. |
Scientists have long been intrigued by why people tend to naturally favour the use of one hand over the other. We still don't fully understand what causes people to be left or right handed, but for decades researchers have assumed that the origin lies inside our brains.
But new research provides early evidence that it's not only the brain that determines handedness - the spinal cord could also play an important role.
An international team of biopsychologists led from the Ruhr University Bochum in Germany has now shown that genetic activity in the spinal cord is already asymmetrical in the womb, and could be linked to a preference for either the right or left hand.
"These results fundamentally change our understanding of the cause of hemispheric asymmetries," the researchers write in the journal eLife.
To be clear, this is nothing more than a hypothesis in its very early stages for now - we need a lot more independently verified research to come out before we throw out decades of work on handedness and the brain.
But despite how preliminary the study is, it suggests an intriguing possibility - what if handedness starts to be determined before our brains are even involved in controlling our movements?
Research has also shown that from the 13th week of pregnancy, unborn children in the womb tend to preference either sucking their left or right thumb.
Because arm and hand movements are initiated by the motor cortex in our brains, scientists had always looked to asymmetric gene expression in the motor cortex and other parts of the brain to explain why this preference happens so early on.
But in the developing embryo, the motor cortex isn't always functionally connected to the spinal cord. In fact, when the earliest indications of hand preference appear, the spinal cord hasn't yet formed a connection with the brain.
"Human foetuses already show considerable asymmetries in arm movements before the motor cortex is functionally linked to the spinal cord, making it more likely that spinal gene expression asymmetries form the molecular basis of handedness," the team writes.
Because of this, the team decided to investigate whether perhaps something happening independently in the spinal cord might influence handedness.
They looked at the gene expression in the spinal cords of five human foetuses between the eighth and 12th week of pregnancy.
The researchers detected differences between the amount of genes being expressed on the right or left side of the spinal cord in the eighth week. Interestingly, this difference was seen in the segments of the spinal cord that control the movements of arms and legs.
The team also looked into what was causing the asymmetric gene activity, and showed that it was environmental factors that seemed to be controlling whether spinal cord activity was greater on the left or right side.
Environmental factors can control gene expression through something known as epigenetics - a layer that sits above our genome and determines which genes are switched on and off.
The study suggests that it's through epigenetics that environmental factors can cause more gene activity on one side of the spinal cord compared to the other.
"Our findings suggest that molecular mechanisms for epigenetic regulation within the spinal cord constitute the starting point for handedness," the researchers conclude.
As we mentioned above, this is a very small and early study, and it's too soon to throw out our current assumptions about handedness just yet. But it's definitely intriguing new evidence that scientists will need to investigate further. |
The origin and purpose of Stonehenge, one of the world's most famous prehistoric monuments, is an enduring mystery. Research shows the massive stone monument on the chalky hills of the Salisbury Plain is part of a larger, complex landscape, with what is known as Stonehenge built between 4,000 and 5,000 years ago – but archaeologists are gradually uncovering more information about southern England's mystifying rocks.
Research published by the Guardian further supports the suggestion Stonehenge may have first been built in what is now Wales, where the monument is believed to have stood for 500 years before being "dismantled and dragged off" to Wiltshire. Archaeologists have discovered a series of holes in the rocky outcrops of Carn Goedog and Craig Rhos-y-felin in the Preseli Hills, Pembrokeshire, which match the rocks of Stonehenge, as well as a "loading bay" where the massive stones could be moved.
But what else do we know about the giant rock structure – and why it was built?
Researchers suggest Salisbury Plain was a sacred site before Stonehenge was built. The area and monument constantly changed until construction decelerated around 4,000 years ago.
The first major construction at Stonehenge was a circular ditch built around 3,000 BC, with an internal bank and a smaller external bank. There were two original entrances to the enclosure – a wider one to the north-east and a smaller one on the southern side. Set inside the bank were 56 pits known as the Aubrey Holes. Around half were excavated in the 1920s and marked with white concrete circles.
Today, Stonehenge has an outer ring of 20- to 30-tonne sandstone blocks and an inner ring and horseshoe of three- to five-tonne volcanic bluestone blocks. The outer blocks, called the sarsen stones, likely originate from what is now the Marlborough Downs in England, about 20 miles north, where sandstone is a common material.
The bluestones, named after their bluish tinge, are understood to have originated from western Wales. Research is ongoing as to how the stones were physically moved the 140 miles from Wales, with some archaeologists suggesting giant ball bearings on tracks were used to shift the giant rocks. There has also been inconclusive research into whether the rocks were shifted by glacial movements in the last ice age.
Standing among the sarsens are the remains of the bluestone circle and inner oval. Today, some of the bluestones have fallen and others are just stumps – they seem to have been chipped and broken from an early date.
Purpose of Stonehenge
There are various theories as to why Stonehenge was constructed, ranging from aliens to an arena for prehistoric raves. In 2013, British archaeologists suggested the monument could have been a burial site for a community of elite families, after analysing the remains of 63 bodies around Stonehenge who were buried over a period of 200 years. The very earliest burials predate the monument in its current form.
Archaeologists have frequently linked Stonehenge to ancient astronomy. In the 1960s, British-born American astronomer Gerald Hawkins proposed the theory that Stonehenge was used to predict solar and lunar eclipses. Using early computer programmes, he found key points in the monuments complex correlated strongly with the rising and setting positions of the sun and moon.
Other research has suggested our ancestors visited Stonehenge to celebrate the winter solstice, an event which continues to be popular today. At midsummer, the sun rises over the horizon to the north-east, close to the Heel Stone. At midwinter, the sun sets in the south-west, in the gap between the two tallest trilithons, one of which has now fallen.
Although Stonehenge is now believed to predate the druids by hundreds of years, antiquary and writer John Aubrey proposed the monument was a druid temple in the 17th and 18th centuries. One new theory, released in 2012 by the Stonehenger Riverside Project, suggests the monument is the result of a "unification of Britain" when people across the UK worked together as a symbol of peace and unity. |
If the massive supervolcano underneath Yellowstone National Park ever erupted, it could spew ash over most of the United States. Of course, the Yellowstone Caldera (as it is formally known) hasn't erupted in about 70,000 years — and it only seems to erupt around every 700,000 years — so it seems unlikely that it will happen again anytime soon. All the same, researchers constantly study the underground volcano looking to understand its behavior. You know, just in case.
Even though the volcano doesn't erupt, it's still quite active, producing the park's famous mud pits and geysers and boiling rivers as heat escapes from beneath the surface. That drives constant change in the park. "The heat from the Yellowstone volcano is what drives the hydrothermal system," Yellowstone geologist Henry Heasler told the Casper Star-Tribune. "It gets hot and rises, and the magma chamber, or reservoir, is at a relatively shallow depth."
Interestingly, that shallow depth causes some changes that cause some people to worry unnecessarily: the very ground in Yellowstone swells and deforms in places. Over the several months a section of the park about 6 miles wide has risen about 1.4 inches and moved nearly half an inch southeast. The Yellowstone Volcano Observatory, operated by the U.S. Geological Survey, says this is completely normal, though. "Episodes of ground deformation, which occur commonly in Yellowstone and at other dormant volcanoes around the world, pose no direct volcanic hazards, nor do they imply that an eruption is pending," reads a recent news release. "They do, however, create a scientific opportunity to better understand the geologic processes at work in Yellowstone and elsewhere. YVO and other scientists are pursuing this opportunity, and will continue to monitor the ground deformation closely."
Among those scientists studying the Yellowstone volcano are University of Wyoming professor of isotope geology Ken Sims, who was in the park this past November with a team of researchers. Using equipment to detect radon and acid levels, Sims told the Star-Tribune that he hopes to figure out what causes the park's well-known steam eruptions. If they can determine the cause, then maybe scientists can also anticipate when certain regions would become volatile (and when tourists should be kept away).
The fact that things change so quickly in Yellowstone offers geologists unique opportunities. "Geology in general is a hard thing to observe," Jacob Lowenstern, lead scientist at the Yellowstone Volcano Observatory, told the Star-Tribune. "It's like watching a rock decompose. In a place like Yellowstone, there are a lot of things that are sped up. That's the truly amazing thing about it."
Studying the volcano also offers a chance to examine the very forces that may have created life on Earth. In fact, an enzyme discovered in a Yellowstone geyser in the 1960s later led to new technologies to study DNA and save lives. (I interviewed one of the scientists behind that discovery a few months ago.)
Even though Yellowstone hasn't erupted in millennia, the researchers are still careful. "When we work in a place that hasn't erupted in 70,000 years, you need to watch and wait and pay attention to what the Earth is saying," Lowenstern told the paper.
Related on MNN: |
Discover when Othello was written and the sources Shakespeare may have used.
Othello was likely written in 1604, after Hamlet and before King Lear. It was performed at court in Whitehall for King James I in November 1604, but may have been previously performed at the Globe.
The play was not published in Shakespeare's lifetime but appeared in a Quarto in 1622, the First Folio in 1623, and a second Quarto in 1630.
Based on a novella in Giraldi Cinthio's Gli Hecatommithi in 1565, which was possibly read in a 1584 French translation. Shakespeare follows Cinthio's plot quite closely, except in the original, Othello returns to Venice to be murdered by his wife's family. Shakespeare also invented the character of Roderigo. However, the moral of Cinthio's cautionary tale about the sad end that waits young women who disobey their parents is completely transformed in Shakespeare's play. |
There are several different ways of looking at the slave trade, but one of the most common descriptions of it is the triangular trade. European merchants brought goods to Africa to trade with the Africans who controlled the slave trade in Africa. They traded these goods for slaves which they then brought to the Americas and traded for cotton, sugar, rum and other goods from the Americas that were generally produced with slave labor. The merchants then returned to Europe bearing the goods from the Americas.
The Africans generally controlled the actual slave market, bringing in captives from tribal warfare as well as from traders who specailzed in simply capturing people for slavery.
The Europeans dominated the other aspects of the trade because they dominated the shipping trade. |
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How we teach computing…
Teachers have both a professional and moral responsibility to prepare pupils for their future life. Computing gives teachers an opportunity to help children develop the transferable technological skills that they will need to integrate into modern society.
The core computing skills and knowledge outlined in the National Curriculum (read by clicking here https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/239033/PRIMARY_national_curriculum_-_Computing.pdf ) are taught discretely in weekly sessions.
Pupils are also given an opportunity to apply these skills, in context, to enhance learning across the curriculum. For example, pupils will be given a chance to apply their understanding of how to use search engines when given the task to research for a purpose within a different subject discipline.
Children have access to both iPads and laptops to facilitate learning in this area of the curriculum, and help them to develop the skills needed to use the different types of hardware they will encounter in life. The core school values of independence, creativity and respect are instilled when learning in this subject: children are given opportunities to work independently; children have the chance to use technology to create content and problem solve and children learn about the importance of being a respectful member of theonline community.
As well as a tool for teaching specific ICT skills, at St. Stephen's Junior school we use iPads to enrich our delivery of the curriculum we offer to your children.
iPads are an effective tool for teaching as, in addition to providing pupils with portable internet access, they are able to run programs called ‘Apps’: many of which are designed to support and enhance the learning experience of children.
A diversity of different ‘Apps’ are available from the Apple App store that you can use at home to support the education of your child. Many are recommended on the link below:
In school we use a number of different Apps, of which some of the most popular are listed below:
- Alex (to help learn coding)
- Garage Band
We like like to use technology to enhance learning at St Stephen's in a variety of ways, for instance with KAHOOT – a way for children to be assessed at the end of the lesson through an interactive quiz!
Coding is an important part of the new Computing curriculum. At school we are currently using a learning resource on the website Purple Mash to facilitate part of this. Feel free to have a look at some of the activities your children will be undertaking by visiting the link below and opening ‘2Code’:
You will need to log in to access the Purple Mash site. Any parents interested, please see your child's respective class teacher.
Lego WeDo 2.0
We have also invested in Lego WeDo to enrich our computing curriculum further, and extend the learning of our older children.
It is a unique combination of LEGO bricks, easy-to-use software and stimulating projects – all aligned to the KS2 computing curriculum and allows our children to make models, and then use the software to create code to instruct the models to perform specific functions.
As described on the Lego Eduation website, LEGO Education WeDo 2.0 makes primary computing a tangible hands-on experience for pupils. With LEGO Education WeDo 2.0, KS2 pupils will be able to get an invaluable head start with the computing curriculum and it encourages them to be curious and ask questions.
www.studio.code.org - is a website that we will be using to teach some of the skills associated with the coding section of the National Curriculum. Children learn about coding here in a variety of exciting ways for example by coding their own Flappy Birds game! It is a resource that can be enjoyed at home as well as in school, so feel free to explore with your children. |
Math and literature
How does combining math and literature help children?How can children's literature strengthen your math program?
Literature can enhance children's awareness of measurement, geometry, numbers and number computation, fractions, classifying, patterns, symmetry, problem solving, reasoning, estimation and more.
Reading literature that presents math problems and concepts as well as clear illustrations can motivate students by:
- helping them connect mathematical ideas to their own experiences
- preparing students for a new math concept or skill
- helping students understand a math skill or concept you are presently teaching
- reviewing math skills and concepts already taught
Books are an inexpensive resource
In the grand scheme of educational resources, books are fairly inexpensive. Use them not only to teach math, but to connect to numerous other subject areas as well. Not only will your students hear a great story, they learn math and other concepts at the same time.
Literature can increase mathematical thinking
Math and literature are a great combination. Many books increase mathematical thinking. Children's literature provides a great jumping off place for math activities. When you are familiar with the math skills early learners are working towards understanding, it is easy to identify books that complement the skill you would like to emphasize. Encourage talking and sharing of ideas among your students.
Connecting math with literature tips
With younger children generally spend about a week building the connections between the math concepts and skills and the story. Here are some suggestions.
- Day 1 - Read the book to the students and enjoy it. Have a sharing circle - those who want to say something about the book have an opportunity.
- Day 2 - Look at some of the pictures in the book, have a teacher directed discussion (still not necessarily about math concepts).
- Day 3 - Reread the story. This time focus the students' attention on the math concept.
- Day 4 - Remind children of the math concept and the book. Have an activity ready to reinforce the story and the math concept.
Always demonstrate the activity first. Just explaining is too confusing. I usually do two demos, the second one showing things that can go wrong. I start it with "This time I am going to make mistakes. Can you guess what I am doing wrong?" The kids find it funny and it reinforces that it's okay if you make mistakes.
Stories that are interesting, that present opportunities to teach math skills, and that have good illustrations are perfect for math and literature connections.
Links to books and activities that promote mathematical thinking:
Beginner book sets
Christmas story map
Hands on literacy activities
Listening and speaking
Make your own worksheets software
Math and literature section
Mini-books - tips for using
Outside activities that encourage reading and writing
Picture books - criteria for choosing and suggestions
Picture books 2
Picture book illustrators
Picture book videos (DVDs)
Responding to literature
"Theme" - check out this section for more literacy ideas |
Geoffrey Chaucer’s The Canterbury Tales depicts an array pilgrims from all walks of life during the 14th century. In his prologue, Chaucer introduces 29 pilgrims that possess a variety of virtues and vices. After concluding their unit on The Canterbury Tales, Ms. Mirabella assigned each of her sophomores the role of a 14th century pilgrim. Students were asked to dress up as different characters in the tales and even recite a homemade poem. Just as the characters in The Canterbury Tales kept many secrets, Ms. Mirabella asked the students to conceal their identity by omitting their pilgrim’s name from their poem. This made the entire presentation engaging and entertaining for all as the class had to guess who each pilgrim was. The activity also served as a live review for all students before their upcoming test. Overall, Ms. Mirabella and the sophomores never fail to team up and make learning fun! |
Weather, the Sun, and How Our Atmosphere is Heated: The Basis of Radiation Heating From Our Sun. The Driving Force As to How Our Atmosphere Works.
Known as the BLACK CAN, SILVER CAN Lab. A MUST HAVE IN ANY EARTH SCIENCE CLASSROOM! Incorporates mathematics, graph reading, instrumentation use, data collection, data analysis, applications, and scientific conclusions.
No materials, NO PROBLEM!
THIS LAB CAN BE DONE WITH THE NECESSARY MATERIALS OR THE GIVEN INFORMATION THAT SIMULATES THE LAB!!!
The weather on Earth is unique because our atmosphere is unique. Other planets have weather but ours is special because of the Sun’s heat and how different regions are heated in different ways.
Students begin by differentiating between radiation, conduction, and convection. This matching activity involves terminology, definition, and representative image.
In 2 lab scenarios students assign the formal names of the lab materials AND what they represent on Earth.
Using thermometer data from both a black can and silver can, students circle the correct answer when given temperature data at the 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, and 20 minute marks.
After data collection, students can either complete their own graph if they collect their own data or simply use the data provided.
After graphing students complete a series of conclusion questions about the 2 lab scenarios and their connections to Earth and how the atmosphere is heated.
This works well for any level but is GREAT for special education students or college prep learners that need an alternative assessment and may not be great at traditional labs.
Also, perfect for homeschooling!
WIDE RANGE OF ABILITY LEVELS! The application to a diverse body of learners, whether it be age or ability level, is predicated on the fact that the instructor determines the difficulty level of the whole activity or part of the activity based on what information is given and what information is not as well as how verbal questions are presented to the student(s).
This is a thorough and DYNAMIC activity that covers a ton of information about atmospheric heating. This has been used as a pre-class, lab/activity, study guide, review, and assessment. This is an effective teaching tool one on one, in small groups, and as a class when using a Smart Board/Promethean Board/Projection.
A guaranteed hit all around!
A great addition to your meteorology/physical science teaching library.
Within the classroom, this activity has been consistently very successful and acclaimed by students in grades 5th – 10th within multiple types of schools - public, private, and charter.
This work has also been shared at workshops, in-services, and conferences.
Great feedback from parents, teachers, and administrators.
Applicable to many state science assessments and benchmarks.
Has been applied to state mandated North Carolina end of year tests for science in grades 5 and 8.
Even used by teachers in New York State as a preparation for the Earth Science Grade 9 Regents Exam.
Answer key provided.
Our goal is your satisfaction! If you have any questions or concerns, please do not hesitate to contact us and we will promptly assist you. Your feedback is very valuable to us as we strive to produce the highest quality products possible.
*Activity designed, completed, and submitted at private residence/educational resource center*
Geo Leo and Meteo Mike
“The Tar Heel Tandem”
“Southern Science Specialists” |
Besides using electrophoresis to separate DNA fragments according to their sizes, it can be used to estimate the actual size, in base pairs, of each fragment. For example, we might be looking for a gene and we suspect it is of a certain size; electrophoresis can be used to locate fragments in that size range. In order to do this, we would need to run a gel with a mixture of DNA fragments of known sizes. This mixture called a "marker" or "ladder," serves as a control or a standard to which we can compare the positions of other DNA bands in the same gel.
In the diagram, below, the "marker" lane contains 10 DNA bands of known sizes. These sizes are given below. Using this information and the plasmid maps of pARA and pKAN-R, predict the positions of DNA bands produced the pARA -, pARA +, pKAN-R-, pKAN-R + samples. Hint: first determine how many fragments should appear in each sample, and then determine the size(s) of each fragment. We will omit the "LIG" sample. |
This course has been updated for 2017-2018 using new books and teaching sequences.
Teachers on this course will explore the writing process in KS1, including ways to develop classroom literacy environments and key routines for writing in order to support children as developing writers. They will look closely at the important contribution made by quality texts and the use of creative approaches to develop language, imagination and structure talk and thinking in preparation for writing.
Teachers will have the opportunity to write across a range of genres to explore the importance of modelled writing. The course will also explore how to make writing a cohesive experience, including how to embed phonics, spelling, vocabulary and grammar in a text based unit of work.
Participants will gain:
"The course has reignited my passion for literacy. I've got a vast range of ideas I can easily adapt to my classroom."KS1 Teacher, 2017
"Learning to write begins - whatever the learner’s age with seeing oneself as a writer, doing the things writers do, and thinking the way writers think. Teachers have a crucial role to play here... "Smith, F (1994:180) |
Statics is the branch of engineering physics that deals with objects at rest. Newton's Second Law of Motion forms the entire mathematical basis for the study: it says, quite simply, F = m * a . Statics takes this in several directions, arriving at a cornucopia of useful equations for discerning the internal forces on a structure at rest.
First, a is reduced to zero, via Newton's First Law of Motion. This means that regardless of the mass of the objects, something is holding them still, and there is no net acceleration. That something must be an opposing force (see Newton's Third Law of Motion), which leads us to the fundamental equation of statics:
ΣF = 0
That's it. "The sum of the forces equals zero." Not only that, but you get a freebie dealing with angular momentum as well. Since the object is neither moving nor spinning, you can assume that there is also no net torque on it; here we represent torque with a capital "M" for "moment". Because ΣM = ΣF * d, and ΣF = 0, we know that
ΣM = 0
"The sum of the torques equals zero." Again, utter simplicity.
These two rules are true for every single direction. For instance, all of the parallel forces in the horizontal direction sum to zero; so do the ones in the vertical. So do the ones canted 33o. All of them sum to zero. A rock sitting on a table has two forces on it, both in the vertical direction: gravity, trying to accelerate its mass downward at 9.8 m/s2, and the table, trying to hold it still, pushing back with the exact same force. If the rock weighs ten kilograms, then the downward force is 98 Newtons, and the table is pushing back with 98 N of force also. Somewhat boring, but that's the way things go in one-dimensional statics.
Because of the work of Descartes and his proofs about perpendicular vectors, we can choose one axis for each dimension we're working with (x; x and y; or x, y, and z -- all mutually perpendicular) and do our summations in 1-, 2-, or 3- space. Our new rules become
ΣFx + ΣFy + ΣFz = 0
ΣMx + ΣMy + ΣMz = 0
This is still read as "the sum of all forces and the sum of all moments are each equal to zero." The rest of statics is just figuring out how to calculate the various forces. Let's look at our rock again. Let's suppose there's a very stiff breeze exerting a force of 3N on the rock, and a prehistoric pseudo-rodent trying to push this rock across the table, perpendicular to the direction of the wind, with a force of 4N. He's not very bright, is he? Well, that's why Allotheria are extinct. Always going around pushing on rocks... So. Let's declare three axes: x will be the direction of the wind, y will be the pseudo-rodent, and z will be gravity. The table pushes back with 98 Newtons and nullifies gravity, and something holds the rock in place against the wind and the prehistoric pseudo-rodent.
It's friction, for those of you impatient with statics and eager to move on to a node about Butterfinger McFlurrys or some such. By the Pythagorean theorem, we know that the force of friction is 5N (draw a free body diagram if you don't believe me). From this, an engineer can apply the static friction equation (Jeeves has an outstanding writeup there) and tell you about the interesting properties of the underside of a rock. What this tells us about engineers is left as an exercise to the reader.
If statics isn't exciting enough for you, perhaps you'd like to learn about dynamics, where things move. It's really not that much more complex until you start doing the math. |
The Mesozoic Era begins where the upheavals of the Permian Extinctions
end. A mass extinction at the end of the Permian Period had eliminated
most of the species of life that had existed throughout the Paleozoic Era. Sometimes called the Age of Dinosaurs because this era becomes dominated by dinosaurs and reptiles.
Toward the end of the Paleozoic Era the land that would become Europe and Asia slammed into North America. By the time of the Mesozoic Era Pangea the super continent had formed. It was roughly the shape of a “C”. The huge land mass protected the Tethys Ocean which lay across tropical latitudes. Pangea and the Tethys were ringed by the Panthalassic Ocean.
Climate During The Mesozoic
The temperatures, both on land and in the ocean, were much higher than during the Paleozoic, and climates were more tropical in nature. Despite this, the seas were lower, leaving different types of land masses for life to deal with. Over all the Mesozoic Era was dryer than in the Paleozoic Era. There were more deserts and less marshland.
Within the three periods of the Mesozoic Era ( Triassic, Jurassic and Cretaceous) there were times of wide temperature and seasonal variation.
Life Recovers From The Permian Extinctions
It took most of the first and second periods of the Mesozoic, the Triassic and the Jurassic periods, for the diversity of species to recover and achieve some balance. While plant species had survived somewhat better than animals over the Permian Extinction, new types of plants developed to survive the changing conditions.
The warmer drier conditions of the Mesozoic required new reproductive methods in plants. Ferns and gymnosperms developed. Their reproductive methods allowed for good protection of the spores or seeds that would have to get through periods of drought before growing into the infant plant.
Marine LifeThe survivors of the Permian Extinction had very little competition. Corals, mollusks and fish dominated the life in the oceans. Some Reptiles took to the water to become the first air breathing hunters in the oceans. They took on a variety of forms and rose to the top of the food chain.
The Rise of The Reptiles and Dinosaurs
The dominant land animals at the end of the Permian Period were the Synapsids. This group of animals is characterized by having a single hole on each side of the skull behind the eye. They are sometimes called mammal like reptiles. This group nearly became extinct at the close of the Permian Period.
The animals that developed in the Mesozoic needed new body types to survive the extremes of temperature and moisture. Amphibians developed respiratory mechanisms that allowed them to live in or out of the water for extended periods of time. But it was the reptiles that were better adapted to the warmer dryer conditions. They developed thick, leathery skin on both their own bodies and their eggs. The reptiles thrived, dominating the landscape in both size and numbers. They are known as diapsids. Diapsids are characterized by having two openings on each side of the skull behind the eyes.
The dinosaurs evolved from these reptiles and were themselves diapsids. During the Jurassic and Cretaceous Periods the dinosaurs ruled the earth.
Both plants and animals reached giant proportions during the Mesozoic. During the 180 million years of the Era, reptiles lived on land, in seas, and in the air. Small mammals, although not significant during the time, did exist during this era.
Mass Extinction Ends The Mesozoic Era
Another mass extinction occurred at the end of the Cretaceous Period, bringing an end to the dinosaurs and the tropical forests. This extinction, while not as broad and devastating as that at the end of the Permian, had the effect of eliminating a way of life that has not been replicated.
Most researchers agree that the Mesozoic Era ended at least in part due to the impact of an asteroid.
Preceeding the Mesozoic Era is the Paleozoic Era
After the Mesozoic Era is the Cenozoic Era
Return to Clock of Eras |
A new study published in the journal Angewandte Chemie International Edition states that Canadian researchers from McMaster University have developed a sensitivity test to detect deadliest superbugs and infectious disease. The test is capable of detecting superbugs such as C difficile and MRSA.
The test can identify the smallest traces of metabolites, proteins or fragments of DNA which might signal the presence of infectious disease such as respiratory or gastrointestinal. The method is 10,000 times more efficient than the current detection systems. Director of McMaster’s Biointerfaces Institute, John Brennan said the molecular device can be switched on by a specific molecule of their choice which can be a certain type of disease indicator or DNA molecule representing a genome of a virus.
The best advantage of the device is that it does not require a sophisticated environment to carry on the tests. It means the equipment can run at room temperature which will make it a mass product. Scientists are currently figuring out ways to create a portable point-of-care test that would work without lab instruments. They are planning to move the results of the test on a paper surface which will indicate the presence of infection or contamination in people, food or environment. |
Outside of her career as a computer systems engineer, Amita Vadlamudi maintains interests in many subjects, including American history. With the April 2017 confirmation of Neil Gorsuch as the 113th justice of the US Supreme Court, individuals like Amita Vadlamudi may find themselves wondering about the court’s earliest days and its first justices.
On September 24, 1789, five months after taking office as the first president of the United States, George Washington signed the Judiciary Act of 1789, which formally established the US Supreme Court and the rest of the federal judiciary. On the same day, he nominated the court’s first chief justice, John Jay, and five associate justices: John Blair Jr., John Rutledge, William Cushing, James Wilson, and Robert Harrison.
The founding fathers of the United States had empowered the US Congress to create the Supreme Court in the US Constitution, and the US Senate had taken up the Judiciary Act as the first piece of business in the body’s history, passing it on the same day as President Washington’s subsequent signing. Two days later, on September 26, 1789, the Senate confirmed all six of the president’s nominations.
The court first met in February of 1790 and then again in August of the same year. It spent its earliest days determining its responsibilities and organizing the federal court system. The Supreme Court did not rule on its first case until 1792, by which time some of the seats belonged to judges other than those originally nominated by President Washington.
It was not until almost 100 years later that the Supreme Court stabilized its numbers of justices, becoming the nine-member court the country knows today. With his confirmation, Judge Gorsuch joins a judicial body that stands as the ultimate arbiter of disputes related to the Constitution. |
May 13, 2013
Sun Produces An X1.7 Solar Flare, Followed By An X2.8
Lawrence LeBlond for redOrbit.com - Your Universe Online
On Sunday (May 12) the Sun emitted a significant solar flare that is being classified as the first X-class event of 2013. The X1.7 flare, which peaked at about 10 p.m. EDT, was also associated with another solar event known as a coronal mass ejection (CME). While CMEs can release radiation and solar material in the direction they were produced, Sunday´s phenomenon was not directed at Earth.While solar flares also have the potential to release bursts of radiation, they do not pose a threat to humans on Earth. Harmful radiation from flares, such as Sunday´s event, can only affect GPS systems and communication signals that travel in the upper atmosphere. This can disrupt radio signals for as long as the flare occurs.
The “X” denotes the intensity level of the flare, with X-class events being the most intense, much more intense than M-class flares. The number that follows the X provides information on the strength of the flare as well — an X2 flare is twice as intense as and X1 and an X3 is three times as intense.
Sunday´s flare erupted from an active region just out of sight over the left side of the sun. This same region has produced two smaller M-class flares as well. The CME that was associated with Sunday´s flare left the sun at 745 miles per second. NASA said in a statement that while the CME was not Earth-directed it could flank the STEREO-B and Spitzer spacecraft. There is some particle radiation associated with this event, so the space agency said it had alerted the spacecraft operators to put onboard electrical systems on standby to protect them from damaging effects of the radiation.
While Sunday´s impressive X1.7 solar flare was the first X-class flare of 2013, it was not the only one to occur. NASA's Solar Dynamics Observatory (SDO) reported today on Facebook that a second X-class solar flare occurred within 24 hours of the first. This event was even bigger than the first and is classified as an X2.8 flare. This event was also not Earth-directed.
An increased number of flares are relatively common as the Sun's 11-year activity cycle is building toward solar maximum, which is expected to peak this year. The solar cycle has been tracked continuously since it was first discovered in 1843.
Experts said it is normal for so many flares to pop up during this peak time of the cycle. There have been at least a dozen X-class flares since the first one of the current cycle was detected on February 15, 2011. The largest X-class flare in this cycle occurred on August 9, 2011 and was classified as an X6.9. |
Math, Science, and Social Studies Shows
The Milky Way, Moons and Meteorites! (Kindergarten-Third Grade)
The students learn about Earth, Earth’s atmosphere, our solar system, the planets, friction, the greenhouse effect and the difference between meteors, meteorites, and meteoroids. We also talk about stars, shooting stars, planets that look like stars, the moon, and historical figures from space history like Yuri Gargarin, Neil Armstrong and Sally Ride. Click here for the post-assembly worksheet.
“Dino provides a fun and engaging learning experience for our students each year! They are always excited to learn about outer space and science through his music and stories.”
- Laura Bates, Principal, Discovery Ridge Elementary School, Wentzville, Missouri
Dinosaurs and Dragonflies (Kindergarten-Third Grade)
The students learn about three eras of life on Earth: paleozoic means “ancient life” and this age primarily consisted of marine life; mesozoic means “middle life” and this was the age of the reptile or the age of the dinosaur; cenozoic means “new life” and this is the age of the mammal. The students also engage in a puppet show about giant prehistoric dragonflies, learn about the megalodon, the largest shark in the history of the world, and define how to identify a mammal.
Around the World with Dinosaur O’Dell (Kindergarten-Third Grade)
This geographical journey transports students to all seven continents and highlights details about each one. The students learn about the world’s longest river, tallest mountain, and the largest desert. Students also learn the names and locations of all the continents, and important cultural facts about each one. For example, pizza was invented in Europe; piranhas are found in South America’s Amazon river; and basketball was invented in North America.
Music, Language and Math (Preschool-Second Grade)
The students meet a cowboy that doesn’t like taking baths, a space alien that needs help fixing his spaceship and Dino’s grandfather, who tells them stories about making pancakes. All the while, the students engage in songs that reinforce counting odd and even numbers, counting by 3’s, 5’s, and 10’s, as well as counting in English and Spanish. They explore math concepts and vocabulary like odd and even numbers and the word quadruple. As a bonus, the students are reminded of the meaning of the words fiction and nonfiction and they have the opportunity to learn about personal choice and responsibility.
Health and Nutrition Shows
Eat Like a Rabbit, Swim in Peanut Butter, and Other Healthy Tricks (Preschool-Kindergarten)
Dino is the “Nutrition Musician”, and he communicates his message about healthy food and an active lifestyle. The students meet a vegetable-eating rabbit who never stops jumping, an exercising cowboy who swims in peanut butter, and a space alien who tries and fails to fuel his spaceship with junk food. On your mark, get set, let’s get healthy!
Blast-Off to Health! (Kindergarten-Second Grade)
This show was developed in conjunction with Blue Cross Blue Shield of Kansas City and Kansas City Young Audiences. It is similar to Eat Like a Rabbit…, but the message has been adjusted for the early elementary grades. The students learn the Health Countdown: five fruits and veggies, four glasses of water, three glasses of milk, two hours or less of screen time, and one hour of exercise – then blast-off to health!
The Really Awesome, Super-Perfect, Song Writing Workshop! (Fourth-Sixth Grade)
Award winning songwriter Dinosaur O’Dell explores the creative process with a hands-on songwriting workshop. Dino utilizes improvisation, idea generation, and collaboration techniques to tease the rhythm, melody, and lyrics from students’ imaginations. Students are encouraged to use rhyme, alliteration, and poetry to communicate their thoughts through music. Class size is limited to 25 students.
Click here for information on Dino’s accredited teacher training: Motivation, Interaction, and Space Aliens: How to Trick Earthlings into Learning.
This 2 hour workshop includes theory, examples, and a step-by-step interactive model of how and why to integrate music and stories into the early childhood curriculum. It is an accredited in-service for preschool teachers in Kansas and Missouri.
Show Sound Bites
*approximately 45 minutes long
*can entertain and educate up to 250 students
*target audience varies with theme: range is preschool-third grade
*six show themes currently available
*student experience is motivating and interactive
*students will sing, dance, act, and dialogue with Dino and each other
*shows encourage physical coordination, mental focus, and social awareness
*student activity sheets available for reinforcing the content
*musical styles presented: blues, country, klezmer, polka, funk, rap, reggae, and rock ‘n roll
*small performance area with an electrical outlet is required
*sound system is provided |
This paper model is a Knarr (Viking Cargo Ship), a type of Norse merchant ship famously used by the Vikings, designed by Inkjet Paper Scissors. Knarr is of the same clinker-built method used to construct longships, karves, and faerings.
The name knarr is the Old Norse term for ships that were built for Atlantic voyages. The knarr was a cargo ship, the hull was wider, deeper and shorter than a longship, and could take more cargo and be operated by smaller crews. They were built with a length of about 54 feet (16m), a beam of 15 feet (4.5m), and a hull capable of carrying up to 24 tons. It was primarily used to transport trading goods like walrus ivory, wool, timber, wheat, furs and pelts, armour, slaves, honey, and weapons. It was also used to supply food, drink, and weapons and armour to warriors and traders along their journeys across the Baltic, the Mediterranean and other seas. Knarrer routinely crossed the North Atlantic carrying livestock such as sheep and horses, and stores to Norse settlements in Iceland, Greenland and Vinland as well as trading goods to trading posts in the British Isles, Continental Europe and possibly the Middle East.
The only knarr found to be well preserved was in a shallow channel in Roskilde Fjord in Denmark of 1962 along with two warships, a Baltic trader, and a ferryboat. Archaeologists believe that the ships were placed there to block the channel against enemy raiders. Today, all five ships, known as the Skuldelev ships, are being restored at the Viking Ship Museum in Roskilde.
The knarr might have been in use in colonizing Iceland, Greenland, and Vinland, although the similar small cargo vessel the byrthing is another major possibility.
You can download this ship paper craft model here: Viking Cargo Ship (Knarr) Free Paper Model Download |
Governor-General of India
The Governor-General of India was the head of the British administration in British India. It was created in 1773, with the title of "Governor-General of the Presidency of Fort William". In the beginning the officer had direct control only over Fort William, but supervised other British East India Company officials in India. However in 1833 the Governor was given complete control over all of British India and from then on was known as the Governor-General of India.
History[change | change source]
Many parts of India were governed by the East India Company, which was supposed to be agents of the Mughal Emperor.
After the Indian Rebellion of 1857 the East India Company was abolished and the lands it had overned in the Indian sub-continent ware put under the direct control of the government of Britain. The Governor-General headed the central Government of India in Calcutta and was responsible to the imperial government in London. The rest of the sub-continent was administered by a large number of princely rulers under the supreme authority of Britain. The Governor-General was commonly known as the Viceroy of India because of his secondary role as Britain's representative to these nominally independent princely states.
Although India and Pakistan became independent in 1947, Governors-General stayed on to represent the Monarch of Great Britain until each rewrote their laws to become republics. When Pakistan and India become independent in 1947 King George who had been before then been the Emperor of India became the King of both countries.
However when India became a republic in 1950 he was no longer king of that country, however he remained king of Pakistan until his death in 1952. After that Elizabeth become Queen until 1956 when Pakistan too became a republic. |
|Political party:|| Whig (1834–1854)
Republican (1854–1865) National Union (1864–1865)
|Born||February 12, 1809|
|Died||April 15, 1865 (aged 56)|
Abraham Lincoln was a great, liberal President who is most notable for freeing the slaves. He was a Republican in his day, back when "Republican" basically meant anything from Radical, Moderate (Liberal), to Conservative. Lincoln was first elected President as a moderate Republican, but would leave the Republican Party in 1864 and be re-elected as a member of the National Union Party. He would most likely be ashamed to see the modern GOP and the acts of George W. Bush.
He was the first president to be assassinated and the first with a beard.
Abraham Lincoln's politics can be challenging to define. He was the first successful Presidential Candidate of the new Republican Party. Within the Republican Party of the time, Lincoln was known as a moderate. He was definitely Liberal, but the Republicans of the time contained a radical wing.
- Free Soil Republican - he believed in stopping the spread of slavery to new territories or States. At the time, free soil Republicanism was the single issue that seemed to unite the Party.
- Unionist - Above all he believed in the preservation of the Union. He was willing to compromise many of his personal political goals to preserve the Union, and in 1865, he ran for re-election as a National Union candidate. For example, he was willing to accept the Corwin Amendment if it would maintain the Union.
- Slave Trade - For many years prior to Lincoln's Presidency, the Atlantic Slave Trade, though illegal, had been allowed to continue through lack of enforcement. Lincoln favored the enforcement of these laws.
- Compensated Emancipation - He was a long time advocate of Compensated Emancipation. He'd written several plans for Compensated Emancipation throughout his political career. These plans called for the gradual elimination of slavery, payments to slave owners, and programs for either education and eventual franchise, or resettlement of emancipated people. None of the plans he had personally written were adopted, but a plan instituted in Washington DC had his input and support.
- Protective Tariffs - Lincoln and the Republican Party supported Protective Tariffs. Protective tariffs had been perhaps the second most sectionally divisive issue of the pre-war Union. Protective tariffs were felt by Southerners to be as much a transfer of wealth from south to north as a source of revenue for government. Many Southerners felt that the spread of slavery was absolutely tied to resistance of protective tariffs, and saw the Republican platform combination of both free soil and protective tariff as a direct attack of their interests. The protective tariff plank was conspicuously absent in the National Union Party (Not Republican though supported by many Republicans) platform of 1864.
- Extension of Political Franchise - Lincoln's Policies evolved over the course of his administration (that's what happens to liberals). He felt constrained both by the Constitution, and his perception of what society would accept, so his policies often differed from his beliefs. He did believe in extension of suffrage, but he also believed that the political franchise should not be extended to those people incapable of the responsible exercise of those rights and responsibilities. In the Campaign of 1864, Lincoln and his National Union Party advocated adoption of the 13th Amendment. Shortly before his death, he urged the States to extend the political franchise to the wisest of African-Americans and to African-American veterans.
- Nationalist or Federalist? - He did support a stronger national Government, but was concerned about preserving States Rights. His choice of Andrew Johnson as running mate, and the Party of National Unity for his second term is indication of his reluctance to destroy the Federal system.
- First Federal Graduated Income Tax - In 1861, President Lincoln proposed and instituted a Graduated Federal Income Tax. This was not only a new form of taxation for the United States, it was progressive.
- Free Markets, Free enterprise and Capitalism -
"Labor is prior to and independent of capital. Capital is only the fruit of labor, and could never have existed if labor had not first existed. Labor is the superior of capital, and deserves much the higher consideration. Capital has its rights, which are as worthy of protection as any other rights. Nor is it denied that there is, and probably always will be, a relation between labor and capital producing mutual benefits. The error is in assuming that the whole labor of community exists within that relation. A few men own capital, and that few avoid labor themselves, and with their capital hire or buy another few to labor for them. A large majority belong to neither class--neither work for others nor have others working for them. In most of the Southern States a majority of the whole people of all colors are neither slaves nor masters, while in the Northern a large majority are neither hirers nor hired. Men, with their families--wives, sons, and daughters--work for themselves on their farms, in their houses, and in their shops, taking the whole product to themselves, and asking no favors of capital on the one hand nor of hired laborers or slaves on the other. It is not forgotten that a considerable number of persons mingle their own labor with capital; that is, they labor with their own hands and also buy or hire others to labor for them; but this is only a mixed and not a distinct class. No principle stated is disturbed by the existence of this mixed class.
Again, as has already been said, there is not of necessity any such thing as the free hired laborer being fixed to that condition for life. Many independent men everywhere in these States a few years back in their lives were hired laborers. The prudent, penniless beginner in the world labors for wages awhile, saves a surplus with which to buy tools or land for himself, then labors on his own account another while, and at length hires another new beginner to help him. This is the just and generous and prosperous system which opens the way to all, gives hope to all, and consequent energy and progress and improvement of condition to all. No men living are more worthy to be trusted than those who toil up from poverty; none less inclined to take or touch aught which they have not honestly earned. Let them beware of surrendering a political power which they already possess, and which if surrendered will surely be used to close the door of advancement against such as they and to fix new disabilities and burdens upon them till all of liberty shall be lost." Annual Message to Congress December 3, 1861
Achievement and deathEdit
Mr. Lincoln was very strong executive, willing to consider opposing points of view, but unwavering in his resolve to preserve the Union. Many of his actions have to be considered Unconstitutional (actions in the border states), but whether those actions were rash or necessary to the preservation of the Union is the question we should hold in mind when judging his actions.
He was, unfortunately, shot and killed by an angry Southern Democrat (which at the time, meant conservative) who supported slavery and was angered after Abraham Lincoln got rid of it. Slavery is, and was, utterly Evil. Therefore, we can conclude that John Wilkes Booth, the man who shot him, was also evil (or didn't understand right from wrong), and that the lack of Lincoln's leadership may have contributed to the excesses of Republican Reconstruction.
"You can fool some of the people all of the time, and all of the people some of the time, but you cannot fool all of the people all of the time". Abraham Lincoln
"Better to remain silent and be thought a fool than to speak out and remove all doubt."
Abraham Lincoln's Religious BeliefsEdit
Contrary to popular belief, Abraham Lincoln was neither an atheist nor a member of any Christian Church of his time, though his parents came from a Calvinist background. In his 1846 race for Congress, Lincoln faced had to respond to the then-damaging allegation that he was a Free-thinker who scoffed a Christian doctrine. Lincoln issued the formal reply, "That I am not a member of any Christian Church, is true; but I have never denied the truth of the Scriptures; and I have never spoken with intentional disrespect of religion in general, nor of any denomination of Christianity in particular." He also indicated that "in early life, I was inclined to believe in what I understand is called the 'Doctrine of Necessity' - that is, that the Human mind is compelled to action, or held at rest by some power, over which the mind itself has no control," and that he had sometimes attempted to mantain such an opinion in argument. Lincoln found the emotionalism of frontier evangelists deeply unappealing. Despite this his parents' Baptist belief in predestination seems to have been a feature of his personal beliefs throughout his life (though in the form of being foreordaiend by immutable natural laws rather than by a personal Deity). Lincoln seems to have become more religious following the stresses of the Civil War and the death of his oldest son (according to his wife, at least). On the whole, his religious views seemed to have inclined from Deism towards some form of Gnostic Monotheism as his life wore on, and it is unclear how much he believed in his own political rhetoric on the subject to the Union at large (which seemed more specifically Christian at times).
Fun Section Edit
His last words were "Good thing these tickets were free, Major Rathbone, this play su-"
- ↑ Did President Lincoln Believe in God?
- ↑ http://www.lib.niu.edu/2006/ih060934.html
- ↑ https://archive.org/stream/annualmessageofp00unit#page/18/mode/2up/search/labor+is+prior
- ↑ Abraham Lincoln
- ↑ Abraham Lincoln
- Lincoln and Liberty - 1860 Campaign Song Campaign song that helped Lincoln win the Presidency |
1. Copy one sheet per pair of students, and cut the sheets up into A and B.
2. Put the students into pairs with an A and B student, and distribute the worksheets.
3. Focus students' attention on the instructions and make sure students aren't looking at each other's sheets. Students first write the question words in the gaps and choosing the correct answer. Depending on group ability, the question words can be checked as a group.
4. Next, allow students the time necessary to read out their questions and answers. Their partner tells them if they are correct or not. Students swap.
5. Monitor the students, providing language input or error correction when necessary.
6. Finally, elicit responses from some of the students and draw to their attention any appropriate vocabulary or serious language mistakes. |
Diversification of life
During the Ordovician Period, life diversified to an unprecedented degree, undergoing a fourfold increase in the number of genera. This unique period, known as the Ordovician radiation, unfolded over tens of millions of years and produced organisms that would dominate marine ecosystems for the remainder of the Paleozoic Era. The Ordovician radiation was an extension of the Cambrian explosion, an event during which all modern marine phyla appeared (with the exception of the bryozoans, which emerged during the Ordovician). The Ordovician continued this diversification at lower levels of taxonomy and saw a rapid increase in the amount of habitats and ecological niches exploited by living things, as well as an increase in the complexity of biological communities.
The number of marine genera in most of the Early Ordovician Epoch was comparable to that seen in the Cambrian Period and had comparable rates of species turnover or extinction. By the latest age of the Early Ordovician Epoch, trilobites and other organisms dominant in the Cambrian were replaced by a wide range of other marine invertebrates, including corals, bryozoans, brachiopods, mollusks, echinoderms, graptolites, and conodonts. One theory posits that diversification reached a peak by the first age of the Late Ordovician Epoch, with minor fluctuations. On the other hand, it has also been argued that this early Late Ordovician “peak” only represents a higher-quality fossil record than that of later Ordovician times. When this difference is accounted for, diversity is seen to rise to a plateau by the Middle Ordovician, after which it changes little.
The timing of diversification differs for each group of organisms and on each of the Ordovician continents. For example, graptolites reached their peak diversity in the Early Ordovician Epoch, whereas gastropods continued to diversify steadily through the entire Ordovician Period. Similarly, overall diversity on the cratons of Laurentia and Baltica peaked in the early Late Ordovician Epoch, whereas diversity peaked in South China in the Early Ordovician Epoch. These intercontinental differences suggest that global diversification was driven by changes unique to each continent rather than by a single global factor.
Exploitation of habitats
The Ordovician radiation began in shallow marine environments and proceeded into deeper water. Newer fauna intermingled with older Cambrian fauna, which was primarily made up of various trilobites and inarticulate (unjointed) brachiopods living in a wide range of environments between the shore and the continental slope. In the Early Ordovician Epoch, articulate (jointed) brachiopods, gastropods, and cephalopods appeared in shallow-water habitats as inarticulate brachiopods and trilobites declined in those habitats. Through the remainder of the Ordovician Period, articulate brachiopods and gastropods continued to spread farther offshore as trilobites and inarticulate brachiopods became rarer in all but deepwater habitats. Finally, in the Late Ordovician Epoch, bivalve communities appeared in shallow-water habitats and displaced the brachiopod-gastropod communities offshore.
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Earth’s Features: Fact or Fiction
Much of the increase in diversity occurring during the Ordovician Period took place within biological communities formed during the Cambrian Period. New species made use of unexploited niches within these communities. Another large portion of this new diversity came from increased provinciality—that is, the differences in the species present between one continent and another. Since most species did not expand beyond their own local regions, the species assemblages of many areas were unique, and few species were distributed globally. Diversity was also increased because of the expansion of life into new habitats not present in the Cambrian, such as reefs, hardgrounds, bryozoan thickets, and crinoid gardens.
Ordovician communities were ecologically more complicated than Cambrian ones. The Ordovician saw the rise of several new life habits, including deep-deposit feeders, mobile epifaunal (superficially attached) carnivores, and pelagic (open-water) carnivores. In contrast to Cambrian communities that lived very close to the sediment surface, Ordovician communities also grew up to 50 cm (1.5 feet) above the seafloor and established distinct tiers, or levels, similar to those present in modern forests. Also, invertebrates burrowed into the seafloor more intensely during the Ordovician Period than in the Cambrian Period, reaching depths of up to 1 metre (3 feet) below the seafloor.
The causes of the Ordovician radiation remain unclear. One view points to the Middle Ordovician fall in sea level, although this event has also been coupled to a global drop in diversity. Another view posits that biological interactions or an inherently higher rate of speciation in some groups fostered the diversification. Others have noted the correlation between the Ordovician diversification and the increase in global orogenic and volcanic activity. Indeed, on continents affected by orogenic activity, diversity proceeded at a faster pace than on other continents, suggesting that an increase in the supply of some nutrients, such as phosphorous and potassium, during the process of uplift may have fueled the diversification.
Mass extinction at the end of the Ordovician
The Ordovician Period was terminated by an interval of mass extinction. This extinction interval ranks second in severity to the one that occurred at the boundary between the Permian and Triassic periods in terms of the percentage of marine families affected, and it was almost twice as severe as the extinction event that occurred at the end of the Cretaceous Period, which is famous for bringing an end to the dinosaurs. An estimated 85 percent of all Ordovician species became extinct during the end-Ordovician extinction in the nearly two-million-year-long Hirnantian Age and the subsequent Rhuddanian Age of the Silurian Period.
Brachiopods display the effects of this extinction well. Laurentian brachiopods were hit hard, particularly those that lived in the broad and shallow seas both within and near the continent. Many of these brachiopods were endemic (confined to a particular region) to Laurentia, as opposed to the more cosmopolitan (globally distributed) forms that lived at the edges of the continent. Following the extinction, Laurentian seas were repopulated with brachiopod genera previously found only on other continents. As a result, Silurian brachiopods were far more widely distributed than their Ordovician predecessors. Other groups of organisms—including conodonts, acritarchs (a catchall group of various small microfossils), bryozoans, and trilobites—that showed this pattern of regional, but not global, distribution were similarly affected by this extinction event. Despite the intensity of the extinction and the loss of many endemic species, Silurian ecosystems were remarkably similar to those in the Ordovician.
The extinction appears to have occurred in several phases. An early phase affecting graptolites, brachiopods, and trilobites occurred prior to the end of the Ordovician Period, before the major fall in sea level. A second phase of extinction occurred as sea levels fell because of the onset of glaciation over the African and South American portions of Gondwana. In many areas the interval of glaciation was accompanied by the invasion of cool-water brachiopod fauna, even into tropical latitudes, suggesting the onset of significant global cooling. A third phase of extinction occurred with the rise of sea level that took place during the Rhuddanian Age of the Silurian Period.
The cause of the end-Ordovician extinction is generally attributed to two factors: the first wave of extinction may be related to rapid cooling at the end of the Ordovician Period, and the second phase is widely regarded as having been caused by the sea-level fall associated with the glaciation. The drop in sea level would have drained the large epicontinental seas and reduced the available habitat for organisms that favoured those settings. No concentration of iridium has been identified near the extinction that would suggest a bolide (meteoroid or asteroid) impact like the one identified at the boundary between the Cretaceous and Paleogene periods. |
These findings, and clues to what powers the geyser eruptions, are presented in two articles published in the current online edition of the Astronomical Journal.
Over a period of almost seven years, Cassini's cameras surveyed the south polar terrain of the small moon, a unique geological basin renowned for its four prominent "tiger stripe" fractures and the geysers of tiny icy particles and water vapor first sighted there nearly 10 years ago. The result of the survey is a map of 101 geysers, each erupting from one of the tiger stripe fractures, and the discovery that individual geysers are coincident with small hot spots. These relationships pointed the way to the geysers' origin.
After the first sighting of the geysers in 2005, scientists suspected repeated flexing of Enceladus by Saturn's tides as the moon orbits the planet had something to do with their behavior. One suggestion included the back-and-forth rubbing of opposing walls of the fractures generating frictional heat that turned ice into geyser-forming vapor and liquid.
Alternate views held that the opening and closing of the fractures allowed water vapor from below to reach the surface. Before this new study, it was not clear which process was the dominating influence. Nor was it certain whether excess heat emitted by Enceladus was everywhere correlated with geyser activity.
To determine the surface locations of the geysers, researchers employed the same process of triangulation used historically to survey geological features on Earth, such as mountains. When the researchers compared the geysers' locations with low-resolution maps of thermal emission, it became apparent the greatest geyser activity coincided with the greatest thermal radiation. Comparisons between the geysers and tidal stresses revealed similar connections. However, these correlations alone were insufficient to answer the question, "What produces what?"
The answer to this mystery came from comparison of the survey results with high-resolution data collected in 2010 by Cassini's heat-sensing instruments. Individual geysers were found to coincide with small-scale hot spots, only a few dozen feet (or tens of meters) across, which were too small to be produced by frictional heating, but the right size to be the result of condensation of vapor on the near-surface walls of the fractures. This immediately implicated the hot spots as the signature of the geysering process.
"Once we had these results in hand we knew right away heat was not causing the geysers, but vice versa," said Carolyn Porco, leader of the Cassini imaging team from the Space Science Institute in Boulder, Colorado, and lead author of the first paper. "It also told us the geysers are not a near-surface phenomenon, but have much deeper roots."
Thanks to recent analysis of Cassini gravity data, the researchers concluded the only plausible source of the material forming the geysers is the sea now known to exist beneath the ice shell. They also found that narrow pathways through the ice shell can remain open from the sea all the way to the surface, if filled with liquid water.
In the companion paper, the authors report the brightness of the plume formed by all the geysers, as seen with Cassini's high resolution cameras, changes periodically as Enceladus orbits Saturn. Armed with the conclusion the opening and closing of the fractures modulates the venting, the authors compared the observations with the expected venting schedule due to tides.
They found the simplest model of tidal flexing provides a good match for the brightness variations Cassini observes, but it does not predict the time when the plume begins to brighten. Some other important effect is present and the authors considered several in the course of their work.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory (JPL) in Pasadena, California, manages the mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team consists of scientists from the United States, England, France and Germany. The imaging team is based at the Space Science Institute.
Additional details, images and an animation are available at:
More information about Cassini is available at:
Dwayne Brown, Headquarters, Washington, 202-358-1726
Email Contact Preston Dyches, Jet Propulsion Laboratory, Pasadena, Calif., 818-354-7013
Email Contact Steve Mullins, Space Science Institute, Boulder, Colo., 720-974-5859 |
Sounds in the Stratosphere
Months of research hung on a 500-foot tall balloon.
Daniel Bowman had watched it slowly fill with air for hours, hoping that his small box of equipment would survive the stratosphere.
For the past two years, Bowman, a doctoral candidate in geophysics at UNC-Chapel Hill, has strapped microphones and other sound sensors to the High Altitude Student Platform (HASP), a NASA balloon that can reach heights of up to 23 miles.
In August 2015, he traveled for the second time more than 1,600 miles from Chapel Hill to Fort Sumner, New Mexico, where everything was now out of his hands. All he could do was ready for launch and watch the balloon slowly lift, shrinking into a tiny white dot in the cloudless sky.
Bowman is among the first to record infrasound in the stratosphere, a sound with a frequency lower than humans can hear.
He believes the sounds humans make, from the rush of planes to the dull hums of air conditioners, could be heating the atmosphere, but it could take five to 10 years to prove his theory and understand the implications — that civilization may affect the environment in ways previously unseen.
Bowman said the atmosphere we know is two-dimensional, but he hopes his research can help people understand the atmosphere as a three-dimensional space.
“I like the atmosphere because I can see it,” he said. “I can see what’s going on. Solid earth, you can’t really see and it doesn’t change over a human lifetime. The atmosphere you can see it and turn around and five minutes later it is completely different.”
According to Bowman’s theory, acoustic waves carry energy into the atmosphere, but they can’t travel forever into space. When they get to the thermosphere, the uppermost part of the atmosphere, they lose that energy, and the energy gets transferred to heat.
Scientists have tried to calculate how much energy is being transferred to the atmosphere from the ground, but Bowman said measuring acoustic waves from the Earth’s surface does not provide the most accurate results. Taking to the sky is the first step to finding the answer.
Bowman wasn’t always a balloon man.
When he first came to UNC-CH, Bowman started studying volcanoes and the sound waves surrounding volcanic eruptions. He started by measuring sound on the ground, but found he was missing some signals.
“I started to think of ways to put microphones in the air,” he said.
Bowman began ballooning. At first he tried tethering the balloons and setting off explosions under them to simulate a volcanic eruption. All of the balloons snapped free. He needed to find a way for a balloon to fly freely while collecting data.
He found the HASP balloon by accident in an email from a NASA listserv, one he would have normally sent to junk mail. This was his chance to test a free-flying balloon. What he recorded temporarily shelved his volcano research.
“We thought, ‘OK, we’ll do this project, we’ll record stuff — I bet someone has done this before — and if nothing is there, we’ll write a paper about how nothing is there, and we’ll move on with our lives,’” he said. “We got the data back and started analyzing it, and it was kind of like, ‘What the hell is this?’
“I’m still planning to go back to the volcanoes, but if you catch a big fish, you tend to let the smaller ones go.”
What does the atmosphere sound like? It is not the question on the forefront of most people’s minds, but to Bowman, it is the question that drives him.
It sounds like the wind howling through a jet engine right before takeoff. Eerie, high-pitched wails are broken up by static and scratching noises like turning the dial of an old radio. Sometimes there is a blip of something — a half-buried frequency among the garbled noise — but it quickly dissipates.
Acoustic waves in the atmosphere is a subject with scant documentation. The last known experiments on the subject were conducted in the mid-1960s by a team from the University of Michigan, but from their research Bowman could not say what the sounds he recorded mean or how they are affecting the atmosphere.
“It was kind of unclear of what they were trying to do,” he said. “I think the idea was just exploration. They did 20 to 30 balloon launches, but the documentation is unclear of what they found. I don’t know if the data even exists anymore — it may be gone.”
Finding the answers to his questions means more balloons and going to even greater heights. Bowman thinks he can achieve this with solar-powered balloons — or what he likes to call the “solar-powered garbage bag.”
“We think we can break the world record in solar power flight with paint drop cloth and packing tape,” he said. “People in a gym could build a 40-foot solar balloon and possibly break all the records of solar balloons, solar-powered airplanes — everything.”
Armed with his giant garbage bag, a sprinkle of coal to power it and a small camera in a Tupperware box, Bowman launched a prototype from the parking lot behind his office in November. It peaked at 72,000 feet before landing just outside Raleigh.
“I think it’s one of the most nerve-wracking things I have ever done,” he said. “Even on the NASA balloons you are not sure if it’s going to work as planned. In my own balloons, I’ve seen a lot of failures. Simply getting a balloon off the ground and clear the trees and clear the buildings and into the sky is 90 percent of the battle. It’s a great feeling to see it go, and it’s an even greater feeling to see it report back its final resting place.”
GPS tracking and smaller sensors have made high-altitude ballooning easier, but the only thing certain in Bowman’s experiments is uncertainty.
Bowman’s sensors on the HASP balloon picked up strange, unexplained noises he thinks may have come from a thunderstorm the balloon passed over, the sound of the ocean and sounds from air conditioners on Earth in his original 2014 launch.
“He has, over time, focused on this unexplained noise, but unless you’re absolutely sure, you can’t say what it is,” said Rachana Gupta, associate director of Electrical and Computer Engineering Design Center at N.C. State.
She and N.C. State graduate student Scott Johnson spent months creating the sensors Bowman mounted on the HASP balloon, and thinking of every possible thing that could go wrong. They had never built anything for a high-altitude balloon before.
Jake Anderson, a graduate student at Boise State University, went with Bowman to the HASP balloon launch to test his own infrasound sensors.
“There’s so much suspense leading up to it,” Anderson said. “You get up really early, you get everything organized on the balloon and then you wait and wait and wait. They have all this rigorous procedure they have to go through. If the weather is not perfect they can call off at any time. The whole time, you’re just hoping, ‘please launch today, please launch today.’”
Anderson developed infrasound sensors that are smaller, lighter and cheaper than many of the existing sensors. He eventually wants to use his sensors to measure infrasound over erupting volcanoes.
“You become more willing to do risky projects and possibly get results you wouldn’t be able to get with the expensive instruments,” he said. “I’m not willing to risk my advisor’s really expensive equipment. He would be pretty mad at me if I blew up $5,000 of his gear.”
After Bowman got the HASP data back almost two months after the 2015 launch, he found the sensors from both teams picked up interfering sounds.
Gupta thinks the sounds Bowman recorded could be from the wind, electrical noises from the other equipment on the balloon or even the balloon itself.
“One of the biggest challenges of this research is finding out what’s real and what’s not,” Bowman said.
Bowman spends most of his time in his office surrounded by computer monitors trying to interpret the slow trickle of data he records from each balloon he launches.
According to the yellowing sign on his door, Bowman works in the seismology office. Though the study of earthquakes brings soil and tectonic plates to mind, he said this is where his advisor puts anyone in the geology department working with sound.
He has managed to cram several plastic storage buckets and crates of equipment, two shoulder-high helium tanks and a work table in the small space.
Cables are strewn across his desk, and he finds himself untangling them every few minutes. In the back corner, there is an old sink filled with empty containers and a counter cluttered with more nests of wires, broken computer monitors, stacks of papers and a stick of deodorant. Posters of the planets — Pluto included — hang across the chalkboard smudged with layers of equations erased and rewritten over and over.
It wouldn’t be a real lab if it were clean, he said.
Here, he assembles balloon packages sent all over the world. One under his desk will be shipped to New Zealand where NASA will launch another balloon in March. The balloon will be drifting over Antarctica for about 100 days.
“The ballooning and infrasound community is so far apart that there’s no transfer, and I think that’s the only reason why this hasn’t been done,” Bowman said. “The will is there, the technology is there, once you bring them together, it’s not really that complicated, but the two elements haven’t come together until we had this opportunity.”
The atmosphere is considered one of the most beautiful, yet unforgiving places on Earth. It burns during the day and freezes at night. The sky is black, and the air is thin. The Earth begins to curve, and the clouds cast wispy shadows on the ground. It is the one place no human could ever go.
“Over the years my perception of the atmosphere has changed,” he said. “I feel like I’m at the bottom of this gigantic ocean that’s flowing over us, and there’s all this stuff going on, and we’re just at the bottom looking up.” |
Consecrating the place to Lincoln's memory really took hold several years later, however, through the efforts begun shortly after the assassination by an African American woman named Charlotte Scott of Virginia. Using her first $5 earned in freedom, Scott kicked-off a fund raising campaign among freed blacks as a way of paying homage to the President who had issued the Emancipation Proclamation that liberated the slaves in the Confederate States. The campaign for the Freedmen's Memorial Monument to Abraham Lincoln, as it was to be known, was not the only effort of the time to build a monument to Lincoln; however, as the only one soliciting contributions exclusively from those who had most directly benefited from Lincoln's act of emancipation it had a special appeal.
In 1959 Congress authorized the National Council of Negro Women to build a memorial to its founder, Mary McLeod Bethune, a well-known African American educator and government advisor. Conceived originally to celebrate the 100th anniversary of the Emancipation Proclamation in 1963, the monument was not dedicated until 1974 because of problems with fundraising (the bronze memorial ended up costing $400,000) and the priority given by the Council, an umbrella organization of African American women's groups, to the efforts of the Civil Rights movement. The sculptor of the Bethune Memorial was Robert Berks, an artist based in New York who also sculpted the gigantic Kennedy bust in the Grand Foyer of Washington's Kennedy Center for the Performing Arts. When it was dedicated in 1974, the Bethune Memorial was the first statue of an African American or a woman of any race on public park land in Washington. (The only previous statue of an African American was that of the freed slave in the Emancipation Group, which was based on Archer Alexander, the last man captured under the Fugitive Slave Act).
Lincoln Park, maintained by the National Park Service, is a public park square that is accessible to the public. |
What Is Anemia?
Anemia is a condition that develops when your blood lacks enough healthy red blood cells or hemoglobin. Hemoglobin is a main part of redblood cells and binds oxygen. If you have too few or abnormal red blood cells, or your hemoglobin is abnormal or low, the cells in your body will not get enough oxygen. Symptoms of anemia — like fatigue — occur because organs aren’t getting what they need to function properly.
Anemia is the most common blood condition in the U.S. It affects about 3.5 million Americans. Women, young children, and people with chronic diseases are at increased risk of anemia. Important factors to remember are:
- Certain forms of anemia are hereditary and infants may be affected from the time of birth.
- Women in the childbearing years are particularly susceptible to iron-deficiency anemia because of the blood loss from menstruationand the increased blood supply demands during pregnancy.
- Older adults also may have a greater risk of developing anemia because of poor diet and other medical conditions.
There are many types of anemia. All are very different in their causes and treatments. Iron-deficiency anemia, the most common type, is very treatable with diet changes and iron supplements. Some forms of anemia — like the mild anemia that develops during pregnancy — are even considered normal. However, some types of anemia may present lifelong health problems. |
Worksheets to practice 3rd grade mathematics, reading and other subjects are freely available from multiple websites for public, private and homeschool use, such as k12reader.com and education.com. Online 3rd grade level activities for student practice are also located at various websites, such as BrainPop, Clever Dragons and DreamBox Learning.Continue Reading
Some 3rd grade level work websites are free to use, while others offer a free trial followed by a monthly or annual payment. Some worksheets and activities may be completed online while others are designed to be printed and completed on paper. Many sites, such as BrainPop, are used in classrooms across the country and provide instructional video lessons, quizzes, interactive games and other materials to help introduce and reinforce concepts. Answers for quizzes and worksheets are usually provided through interactive feedback, at the bottom of printed worksheets or on a separate sheet.
Educational websites with practice exercises and worksheets can usually be sorted by subject, grade level and other quantifiers. Some sites also offer common core standards to practice. Some worksheet examples include acrostic poem forms, multiplying by nine, locating long and short vowels, action and linking verbs and word searches. Fun sheets, such as comics featuring a covered concept, are also provided by some websites.Learn more about K-12 |
When you set up a local area network, you must specify a protocol. A protocol is a set of rules that allow each computer to communicate. Several LAN protocols exists, and some are more widely used than others.
TCP/IP is the main protocol of the Internet. To communicate on the Internet, a network and each client computer must have configurations on the network card that have TCP/IP set up. TCP/IP uses packets of information that contain an IP address, which is a segmented numerical system that indicates the address for a computer. Each computer must have a unique address to function on the network.
The Novell NFS protocol is specific to Novell NetWare networks. Novell NetWare is a server-client architecture that can be used in internal networks. To use the Internet, the Novel NFS protocol should be used with the TCP/IP protocol. Many Novell networks use NFS and TCP/IP simultaneously.
The Apple AppleTalk protocol is mainly used to connect Apple computers and printers. The AppleTalk protocol is only compatible with other Macintosh computers, so it is not widely used unless the network is Apple-specific. Users still must have TCP/IP to use the Internet with an Apple computer.
You can run several protocols on a computer to ensure that the computer can communicate with each client on the network. Heterogeneous networks require multiple network protocols, so each client computer can communicate with another. For instance, multiple protocols are needed for a Windows and Novell client computer to communicate. |
The Best Bullying Prevention Is For Parents To Lead By Example
Bullying is defined as repeated or aggressive behavior against which a child has difficulty defending herself or himself. However, not all unkind behavior is bullying. In fact, teasing and jockeying for status are actually a normal part of childhood and adolescence, and teach young people, through trial and error, important relationship skills for later life. Parents can have an important role in minimizing both unkind behavior and the likelihood of bullying by teaching and modeling positive relationship skills for their children.
Conversation is the first step in the prevention of bullying. A parent who talks about bullying with her or his child for as little as 15 minutes a day increases the probability that their young person will come to them for help and advice. Parents who talk directly about bullying with their teens help them feel supported, learn strategies for responding and increase their ability to stand up for others. Parents can get ideas for starting such conversations from the U.S. Substance Abuse and Mental Health Services Administration's free app KnowBullying.
Parents also help prevent bullying when they model tolerance and inclusion of a variety of people and personalities. A parent who actively shows his or her teen how to get along with others and how to deal with disagreements in a respectful, assertive way demonstrates important relationship skills.
To help young people be more inclusive and understanding, parents can encourage them to think of others' perspectives, particularly when a peer is being inappropriate or annoying.
Parents should avoid slurs themselves and instruct their children never to use derogatory terms such as "gay," "retard" or "slut." Even if the person who is being called a derogatory term says "it's no big deal," using these terms is never OK. Cruel words are always a "big deal."
Finally, parents can structure environments to avert bullying before it takes place. One common source of bullying is technology. No young person should have 24-hour unlimited access to smart phones, texting, computers or other digital media. Parents can establish household rules that require teens and children to use computers and tablets in common areas of the house where parents can monitor screens to know what they are seeing and sending.
Parents should also monitor children's texts, apps and computer history for evidence of bullying. Youth who experience cyberbullying are frequently embarrassed and do not tell their parents about their experiences. Teens often continue to use media even when they experience cyberbullying and would be better off disengaging. By the same token, a parent whose teen is the perpetrator of online harassment is equally likely to be in the dark about the child's bad behavior.
A parent concerned that her or his child is the victim of bullying should contact the child's school or officials at other sites where harassment takes place, or, if necessary, contact the police. Parents of victims should not contact parents of bullies directly. The U.S. Department of Health and Human Services publishes resources about bullying at StopBullying.gov.
Adults can help children increase their awareness of bullying so they can avoid contributing to it and recognize bullying when they see it. Young people also benefit when they understand how to address bullying behavior assertively and safely.
Children look to their parents and caregivers for advice on tough choices and peer pressure. Parents who talk about and model how to advocate appropriately and safely for vulnerable individuals will help prevent bullying.
Ann Clarkson is a digital parenting education specialist with University of Wisconsin-Extension Family Living Programs. She writes for several online parenting resources including two UW-Extension publications for parents of teens: eParenting High Tech Kids and Parenthetical. Becky Mather is education coordinator for the Wisconsin Child Abuse and Neglect Prevention Board.
The Best Bullying Prevention Is For Parents To Lead By Example was originally published on WisContext which produced the article in a partnership between Wisconsin Public Radio, Wisconsin Public Television and Cooperative Extension.
How Parents Can Mitigate The Harm Of Bullying
A Successful Intervention Must Address Children's Social Dynamics
A teen who experiences headaches or stomach aches, has unexplained bruises or injuries or avoids school may be the victim of bullying and needs a parent or caretaker to intervene. A rapid decline in grades is another indication of bullying, as is a teen abruptly dropping activities he or she enjoyed, or demonstrating a markedly increased desire for isolation.
When a parent becomes concerned that a child is being bullied, the parent should listen to the child and calmly determine whether the situation is actual bullying or "drama," which describes normal and often unkind jockeying for status among teens as they mature and develop their understanding of social relationships. Although less threatening than bullying, drama is still one of the most unpleasant aspects of growing up.
Teens can usually handle drama on their own, though perhaps with some advice. Parents can strategize and role play with their children on how to deal with challenging situations. However, in the case of bullying, a parent or someone else with power must intercede and make a significant change in the dynamics. Teens cannot handle bullying themselves without great risk of immediate and perhaps lasting physical and/or emotional damage.
Bullies themselves also are suffering. Signs a child may be bullying others include having friends who are bullies, fighting, getting into trouble at school, suddenly having new things or more money, or always blaming others for problems.
Neither bullies nor their victims are likely to ask for help, so adults must be alert for signs. If a parent becomes aware her or his child is being harassed, he or she should not contact a bully's parent. Parents often get offended and defensive when their children are accused. Bullies may have learned about physical violence from their parents and so adults do not want to put themselves in unsafe situations — or jeopardize the bully's safety. Also, stepping onto someone else's property could lead to an arrest for trespassing.
What can parents do?
When bullying occurs, parents and teens should keep detailed records of incidents, including participants, dates and locations, copies of online interactions and notes on contacts with authorities. When the bullying occurs at a school, parents should learn about its anti-bullying policy and arrange to meet face to face with a principal, teachers and possibly a guidance counselor. During the meeting, a parent should remain calm and matter of fact while relaying a child's story. Parents should never encourage or allow authorities to conduct a meeting between their child and the bully as the power differential makes this an unproductive opportunity that can reinforce the intimidation.
Following a meeting, the parent should write down everything that was discussed and follow up with a thank-you note to everyone who attended. The note should summarize what was said and agreed on at the meeting. If the harassment at school does not stop, parents should be prepared to go to the next level of authority —the district superintendent and, eventually, the school board.
If the bullying takes place at an organized activity, parents should consult the adults in charge. If harassment occurs in public, outside of school or a supervised activity, parents should contact police to intercede. If necessary, parents should obtain restraining orders.
Help is available for parents and their teens to mitigate the harmful impact of bullying. Mental health professionals can help both bullied teens and those who bully to cope and rebuild their self-esteem and sense of safety. Teens can benefit from friends who have also experienced bullying. Parents can find resources from other parents of bullied teens and through organizations such as gay-straight alliances.
Bullying is a serious threat to the well-being of youth. Parents can find watching their children be hurt to be incredibly difficult. One of the best ways they can prevent drama and bullying is by modeling positive relationship skills. When parents raise their children to get along with others and deal with disagreements in a respectful, assertive way, they are giving them important skills to deal with future conflict.
Anne Clarkson is a digital parenting education specialist with University of Wisconsin-Extension Family Living Programs. She writes for several online parenting resources including two UW-Extension publications for parents of teens: eParenting High Tech Kids and Parenthetical. Becky Mather is education coordinator for the Wisconsin Child Abuse and Neglect Prevention Board.
How Parents Can Mitigate The Harm Of Bullying was originally published on WisContext which produced the article in a partnership between Wisconsin Public Radio, Wisconsin Public Television and Cooperative Extension. |
Equal Pay Day: what is it, when did it start?
The term “Equal Pay Day” was used Tuesday at the White House and on Capitol Hill to highlight the pay gap between men and women.
The Census finds that, as median income goes, women earn 77 cents for every dollar a man earns. And the point of holding “Equal Pay Day” around this time of the year is to show how much longer — nearly three months — a woman would have to work to make up that other 23 percent.
There’s even a purpose to holding it on Tuesday — it represents the extra day or two women would have to work to equal the income of men from the previous week.
But all that didn’t start with this White House or any other White House, for that matter.
The phrase dates back to 1996 and was coined by the National Committee on Pay Equity, an all-volunteer group of women who began meeting in 1979.
The women noticed the disparity in median pay and wanted to bring attention to it. So, 18 years ago, they came up with “National Pay Inequity Day.”
But that wonky phrase didn’t get much pick up.
“It didn’t have a good ring to it and was confusing,” said Michele (pronounced Michael) Leber, chairwoman of the group. She’s been on the board since 1985 and a member since its inception.
“Equal Pay Day” sounded a lot better and started to get some traction. And so a Washington phrase was born.
“It has succeeded beyond what we would have expected,” Leber said, noting that a handful of other countries have even recognized it.
But Leber said the 77 percent statistic is often misused.
“Sometimes people say this 77 cents is for people doing the same work, and it’s not,” she said.
The statistic is often cited by Democrats as evidence of pay disparity. Republicans used a similar statistic to point out the aggregate pay disparity in the White House. A study by the American Enterprise Institute, a conservative think tank, found that women in the White House make 88 percent of what men make in the White House. But, just like the 77 percent statistic, that accounts for everyone working and is not about equal pay for equal work.
Leber said the group is pleased with the executive orders and frustrated with Republicans for having blocked the so-called Paycheck Fairness Act, which passed the House twice previously and got 58 votes in the Senate. It is slated to come up for a vote Wednesday and will likely not get the 60 votes needed to overcome a filibuster. And even if it does, it has zero chance of being taken up by the Republican-led House. |
Grade 9 Chemistry Science Projects
Below I have listed 5 complete simple Grade 9 Chemistry Science Fair Projects that you can buy in a bundle for only $1.00 :-) That's right, here they are, all 5 complete Grade 9 Chemistry Science Fair Projects for only $1.00!
- Chemistry 1 - Chemistry Magic - The Balloon Self Inflator The purpose of this science fair project is to understand the reaction between vinegar (a weak acid) and sodium bicarbonate. Acids have many properties such as a sour taste, they dissolve in water to form solutions that conduct electricity, can release hydrogen when add to certain metals, and can neutralize bases.
- Chemistry 2 - The Colorful Properties Of Capillaries How Plants And Trees Gain Nourishment The purpose of this science fair project is to understand how capillaries work in foods such as celery. The stem of a stalk of celery contains tiny tubes called the capillaries. There is a scientific principle called "Capillary Action". Capillary Action is the tendency of liquids in tiny tubes to rise in the tubes. Capillary Action is possible because air pressure that presses on the liquid and the bottom of the celery stalk is greater than the air pressure inside of the stalk.
- Chemistry 3 - The purpose of this science fair project is to explore the rusting effects of chemical oxidation. Oxygen is very reactive and makes up 21% of the atmosphere. The combination of oxygen with substances such as wood, oil and coal are what creates heat and light from flames. This combination of oxygen with other substances is referred to as "oxidation".
- Chemistry 4 - The purpose of this science fair project is to understand Capillary action and siphon action to create Stalactites and Stalagmites. Stalactites are icicle shaped deposits that hang from the roof or sides of a cavern. Stalagmites are inverted icicle shaped deposits that rise up from the floor of a cavern. Capillary Action is a result of the attraction that liquids have to interior solid surfaces in tiny tubes. Siphon action is a result of the weight of liquid in the tiny tube or substance.
- Chemistry 5 - The purpose of this science fair project is to understand how the properties of lemon juice reacts with heat. The acids, sugars, and other chemicals in dried lemon juice will turn brown when placed in front of a heat source. Chromatography will also be explored. Chromatography is the process of spotting a chemical on an absorbent material and dipping an edge of the material in liquid which reveals a spot that separates into colored spots. Use chromatography to create a secret code. |
Our agricultural system is comprised of interconnected resources. The availability of these resources affects how much food we can produce. In this module, you will explore the resources that make up our agricultural system in order to answer the question: can we feed the growing population? Food production is faced with a growing number of challenges, including the availability of resources such as arable land, sunlight, rain and organic matter.
Throughout this module, you will explore land uses and soil quality through graphs of land use and crop production. You will run experiments with computational models to compare the effect of different management strategies on the land. By the end of the module you will be able to describe how humans can maintain and replenish important resources to be able to produce food long into the future.
This module contains five activities, each approximately 45 minutes long. |
In 1959, during the height of the Cold War, the U.S. Army Corps of Engineers built Camp Century, a military base in northwestern Greenland encased completely within the Greenland Ice Sheet. The camp’s official purpose was to test construction techniques in the Arctic and conduct scientific research, but it doubled as a top secret site for testing the feasibility of deploying nuclear missiles that could reach the Soviet Union in case of nuclear war.
Greenland is a Danish territory, and although the United States had Denmark’s approval to build Camp Century, the missile launch program, known as Project Iceworm, was kept secret from the Danish government. Several years after the camp became operational, however, Project Iceworm was rejected by the Joint Chiefs of Staff, and the camp was decommissioned in 1967. The Army Corps of Engineers removed the nuclear reactor that powered the camp but left the camp’s infrastructure and waste behind, under the assumption they would be frozen and buried forever by perpetual snowfall.
But in the decades since Camp Century was abandoned, climate change has warmed the Arctic more than any other region on Earth. Here Colgan et al. take an inventory of the wastes at Camp Century and run climate model simulations to determine whether the waste will stay put in a warming Arctic. The team analyzed historical Army Corps of Engineers documents to determine where the wastes are located, how deep under the ice sheet they are buried, and how much the ice sheet has moved since the 1950s.
The team estimates the site contains 200,000 liters of diesel fuel, enough for a car to circle the globe 80 times. Considering the building materials used in the Arctic at the time, the authors speculate that the site also contains polychlorinated biphenyls (PCBs), which are pollutants toxic to human health. They also estimate the site has 240,000 liters of wastewater, including sewage, along with an unknown volume of low-level radioactive coolant from the nuclear generator.
Looking at existing business-as-usual climate projections, the team determined that as early as 2090, the portion of the ice sheet covering Camp Century could transition from net snowfall to net melt. Melting of the ice would guarantee that the camp’s infrastructure and waste, which represents a significant environmental hazard, would remobilize, according to the authors.
If that happens, pollutants could be transported to the ocean, where they could disrupt marine ecosystems. The authors do not advocate for starting remediation activities at Camp Century now, however. The waste is buried tens of meters below the ice, and any cleanup activities would be costly and technically challenging, according to the researchers, but the new study does raise questions about who is responsible for cleaning up the waste when it is exposed.
Although Camp Century was a U.S. base, it is on Danish soil, and while Greenland is a Danish territory, it is now self-governing. According to the authors, the implications of climate change on such politically ambiguous abandoned wastes have never been considered before. (Geophysical Research Letters, doi:10.1002/2016GL069688, 2016)
—Lauren Lipuma, Contributing Writer |
Compare Fractions with same Numerators - 3rd Grade Math
Compare simple fractions by reasoning about their size on an area model or where they point to, on a number line. It is important to recognize that comparisons are valid only when the two fractions refer to the same whole. In Compare Fractions with Same Numerators Worksheet, students compare fraction with same numerators. As the numerators are equivalent (same number of parts), the fractions with the smaller denominator (larger individual parts) is greater.
Common Core Alignment
3.NF.3.dCompare two fractions with the same numerator or the same denominator by reasoning about their size. Recognize that comparisons are valid only when the two fractions refer to the same whole. Record the results of comparisons with the symbols >, =, or <, and justify the conclusions, e.g., by using a visual fraction model. |
Starting with the number 180, take away 9 again and again, joining up the dots as you go. Watch out - don't join all the dots!
Imagine a wheel with different markings painted on it at regular intervals. Can you predict the colour of the 18th mark? The 100th mark?
If you have only four weights, where could you place them in order to balance this equaliser?
Can you complete this jigsaw of the multiplication square?
Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.
Factors and Multiples game for an adult and child. How can you make sure you win this game?
In this activity, the computer chooses a times table and shifts it. Can you work out the table and the shift each time?
Can you predict when you'll be clapping and when you'll be clicking if you start this rhythm? How about when a friend begins a new rhythm at the same time?
What do the numbers shaded in blue on this hundred square have in common? What do you notice about the pink numbers? How about the shaded numbers in the other squares?
Given the products of adjacent cells, can you complete this Sudoku?
Use the interactivity to create some steady rhythms. How could you create a rhythm which sounds the same forwards as it does backwards?
In a square in which the houses are evenly spaced, numbers 3 and 10 are opposite each other. What is the smallest and what is the largest possible number of houses in the square?
Use the interactivities to complete these Venn diagrams.
A student in a maths class was trying to get some information from her teacher. She was given some clues and then the teacher ended by saying, "Well, how old are they?"
A game for 2 or more people. Starting with 100, subratct a number from 1 to 9 from the total. You score for making an odd number, a number ending in 0 or a multiple of 6.
Arrange the four number cards on the grid, according to the rules, to make a diagonal, vertical or horizontal line.
Can you explain the strategy for winning this game with any target?
Investigate the sum of the numbers on the top and bottom faces of a line of three dice. What do you notice?
Each light in this interactivity turns on according to a rule. What happens when you enter different numbers? Can you find the smallest number that lights up all four lights?
A game for 2 people using a pack of cards Turn over 2 cards and try to make an odd number or a multiple of 3.
Ben passed a third of his counters to Jack, Jack passed a quarter of his counters to Emma and Emma passed a fifth of her counters to Ben. After this they all had the same number of counters.
A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.
How many different shaped boxes can you design for 36 sweets in one layer? Can you arrange the sweets so that no sweets of the same colour are next to each other in any direction?
A mathematician goes into a supermarket and buys four items. Using a calculator she multiplies the cost instead of adding them. How can her answer be the same as the total at the till?
Given the products of diagonally opposite cells - can you complete this Sudoku?
Can you order the digits from 1-3 to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on?
Andrew decorated 20 biscuits to take to a party. He lined them up and put icing on every second biscuit and different decorations on other biscuits. How many biscuits weren't decorated?
Can you fill in this table square? The numbers 2 -12 were used to generate it with just one number used twice.
Find the words hidden inside each of the circles by counting around a certain number of spaces to find each letter in turn.
The planet of Vuvv has seven moons. Can you work out how long it is between each super-eclipse?
In this problem we are looking at sets of parallel sticks that cross each other. What is the least number of crossings you can make? And the greatest?
Can you work out the arrangement of the digits in the square so that the given products are correct? The numbers 1 - 9 may be used once and once only.
Suppose we allow ourselves to use three numbers less than 10 and multiply them together. How many different products can you find? How do you know you've got them all?
Got It game for an adult and child. How can you play so that you know you will always win?
An environment which simulates working with Cuisenaire rods.
A game that tests your understanding of remainders.
What is the lowest number which always leaves a remainder of 1 when divided by each of the numbers from 2 to 10?
Four of these clues are needed to find the chosen number on this grid and four are true but do nothing to help in finding the number. Can you sort out the clues and find the number?
"Ip dip sky blue! Who's 'it'? It's you!" Where would you position yourself so that you are 'it' if there are two players? Three players ...?
Becky created a number plumber which multiplies by 5 and subtracts 4. What do you notice about the numbers that it produces? Can you explain your findings?
Factor track is not a race but a game of skill. The idea is to go round the track in as few moves as possible, keeping to the rules.
I am thinking of three sets of numbers less than 101. They are the red set, the green set and the blue set. Can you find all the numbers in the sets from these clues?
I am thinking of three sets of numbers less than 101. Can you find all the numbers in each set from these clues?
Nearly all of us have made table patterns on hundred squares, that is 10 by 10 grids. This problem looks at the patterns on differently sized square grids.
Follow the clues to find the mystery number.
Does a graph of the triangular numbers cross a graph of the six times table? If so, where? Will a graph of the square numbers cross the times table too?
How can you use just one weighing to find out which box contains the lighter ten coins out of the ten boxes?
The discs for this game are kept in a flat square box with a square hole for each disc. Use the information to find out how many discs of each colour there are in the box.
This article for teachers describes how number arrays can be a useful reprentation for many number concepts.
A game in which players take it in turns to choose a number. Can you block your opponent? |
Music (or mousike) was an integral part of life in the ancient Greek world, and the term covered not only music but also dance, lyrics, and the performance of poetry. A wide range of instruments were used to perform music which was played on all manner of occasions such as religious ceremonies, festivals, private drinking parties (symposia), weddings, funerals, and during athletic and military activities. Music was also an important element of Greek education and dramatic performances held in theatres such as plays, recitals, and competitions.
For the ancient Greeks, music was viewed as quite literally a gift from the gods. The invention of specific instruments is attributed to particular deities: Hermes the lyre, Pan the syrinx (panpipes) and Athena the aulos (flute). In Greek mythology the Muses personified the various elements of music (in the wide Greek sense of the term) and were said to entertain the gods on Mt. Olympus with their divine music, dancing, and singing. Other mythical figures strongly associated with music are the god of wine Dionysos and his followers the Satyrs and Maenads. Amphion and Thamyres were both famed for their skills playing the kithara (guitar) whilst Orpheus was celebrated as a magnificent singer and lyre player.
The oldest surviving Greek musical instruments are bone auloi which date from the Neolithic Age (7th-4th millennium BCE) and were found in western Macedonia, Thessaly, and Mykonos. The three major civilizations of the Bronze Age in the Aegean (3000 to 1000 BCE), Cycladic, Minoan and Mycenaean, all provide physical evidence of the importance of music in their respective cultures. Marble figurines from the Cyclades represent players of both the aulos and the harp. Cretan hieroglyphic script has three symbols which are musical instruments - two types of harp and a sistrum (or rattle, originally from Egypt). An alabaster lyre decorated with swan heads survives from Knossos and a fresco at Akrotiri on Thera depicts a blue monkey playing a small triangular lyre. The Minoan ‘Harvester Vase’ (1500-1450 BCE) from Hagia Triada on Crete depicts a sistrum player and clay versions of the instrument have been found in graves across Crete. There is also some evidence that music may have been written down as early as the Bronze Age if a Minoan Linear A text on a wall in Hagia Triada is interpreted as such.
The combining of words and music, melodic and scalar systems, and several of the most popular musical instruments such as the aulos and lyre probably derived from the Near East. However, the Greeks themselves considered the lyre, in particular, as a ‘Greek’ instrument whilst the aulos is often represented in mythology as an inferior foreign competitor of Eastern origin. Hence, the great Greek god Apollo, who was believed to be the master of the lyre, defeated the Phrygian Satyr Marsyas and his aulos in a musical competition judged by the Muses. The lyre was also the musical instrument, above all others, which young Greeks had to learn in their schooling and was recommended as such by Plato in his Republic.
Greek musical instruments included stringed, wind, and percussion. By far the most popular were the lyre, aulos (usually double), and syrinx. Other instruments, however, included the rattle (sistrum and seistron), cymbals (kymbala), guitar (kithara), bagpipe (askaulos), conch and triton shells (kochlos), trumpet (salpinx), horn (keras), tambourine (rhoptron), shallow drum (tympanon), clappers (krotala), maracas (phormiskoi), xylophone (psithyra), various versions of the lyre such as the four-stringed lyre (phorminx) and the multi-stringed and elongated barbiton, and various types of harps, usually triangular shaped (e.g. the psalterion). Two unusual instruments were the rhombos (a wind instrument) which was a flat rhombus pierced with holes, strung on a cord, and played by spinning the cord. The second was the hydraulis, a sophisticated Hellenistic organ which used compressed air and water pressure maintained by two pedals. Incidentally, stringed instruments were always played with the fingers or a plectrum rather than with a bow and in the Classical period, stringed instruments were favoured over wind as they allowed the player to also sing, and for the Greeks words were considered more important than musical sounds.
There is evidence that the Greeks began to study music theory as early as the 6th century BCE. This consisted of harmonic, acoustic, scalar, and melody studies. The earliest surviving (but fragmentary) text on the subject is the Harmonic Elements by Aristoxenos, written in the 4th century BCE. Music also became an element of philosophical study, notably, by the followers of Pythagoras, who believed that music was a mathematical expression of the cosmic order. Music was also held to have certain therapeutic benefits, even medicinal powers over physical and mental illnesses.
In addition, one of the unique contributions the Greeks made to the history and development of music is that it can have a moral and emotional effect on the listener and his or her soul; in short, that music has an ethical role in society. For this reason, Plato, considering them rather decadent , banned instruments capable of producing all of the scales. Likewise, over-complicated rhythms and music with too fast a tempo were considered morally dangerous in the great philosopher’s ideal republic.
Regarding written music, 52 pieces of Greek music survive, albeit in a fragmentary form. For example, a musical excerpt from Euripedes’ play Orestes survives, as does an inscription of music from the Athenian Treasury at Delphi. The most complete surviving piece of Greek music is the song of Seikilos from a 2nd century BCE tombstone found at Tralleis near Ephesos.
Greek musicians were very often the composers and lyricists of the music they performed. Known as the ‘makers of songs’ or melopoioi, they created melos: a composition of words, tune, and rhythm. There is evidence that musicians enjoyed an elevated status in society as indicated by their particular robes and presence on royal household staff lists. There was even a specific symbol for musicians in the Cretan hieroglyphic script and the later Linear B. Professional musicians were male, although an exception were the courtesans or hetairai who performed at symposia. However, there are depictions in art of female musicians, notably the clay dancing lyre players from Palaikastro. Other professional musicians included the trieraules who set the beat for the rowers in triremes and trumpet players and choral singers who accompanied marching soldiers.
Music & Religion
Music and dancing accompanied processions on special religious occasions in various Greek cities and, amongst the most famous in the Greek world, were the Panathenaia and Great Dionysia festivals of Athens. Certain religious practices were usually performed to music, for example, sacrifices and the pouring of libations. Hymns (parabomia) and prayers (kateuches) were also sung during processions and at the altar itself. These were provided by choral groups of professional musicians, notably aulos players, often attached to particular sanctuaries, for example, the paeanists in Athens and the aoidoi and epispondorchestai in the sanctuary of Asklepius at Epidaurus.
Music, dance, poetry and drama recitals were also a competitive activity in events such as the pan-Hellenic festivals held at Isthmia, Delphi and Nemea. However, as with the athletic competitions, the music contests were of a religious nature in that excellence was offered to honour the gods. There were two types of such musical contest: stephanites (sacred with a symbolic wreath as the prize) and chrematites or thematikoi (with more tangible prizes such as money or precious goods). Sparta, Argos and Paros held the earliest such competitions from the 7th century BCE. In Hellenistic times, musical festivals and competitions became so common that musicians and performing artists began to organize themselves into guilds or Koina.
Music & Education
Plato informs us that the first schools dedicated to musical education were created by the Cretans. However, the heyday of music in the classroom was during the 6th and 5th centuries BCE when schools of music were established in Athens where pupils aged between thirteen and sixteen were taught to play the lyre and kithara and to sing, accompanied by their teacher on the aulos. Music taught discipline and order and allowed the educated to better appreciate musical performance. Athletics and other sporting activities, another major element of the Greek education, were also done accompanied to music, particularly in order to increase synchronization.
Music For Pleasure
Music was a staple element of the symposium or all-male drinking party. After eating, the men each sang a song (skolia) with an aulos, lyre, or barbiton providing backing music. Often they sang amusing satirical songs (silloi). Finally, at the end of the evening, it was common for the group to take to the streets as a komos (band of revellers) and sing and dance their way through the town.
Women too could enjoy music in the privacy of their homes. Usually women played stringed instruments and recited poetry to music. In addition, household chores such as weaving and baking were done to music. Children too sang songs (agermos) at people’s doors to receive small-change and sweets just as carol-singers do today.
In the theatre, performances of tragedy, comedy, and drama were all accompanied by music, and singing was provided by a designated chorus which consisted of as many as 24 singers in theatre performances of the 5th century BCE.
Music in Art
Musicians and musical instruments were a popular subject on frescoes, in sculpture, and on Greek pottery, particularly in the Geometric, black-figure and red-figure styles. Aside from all of the major mythological figures previously mentioned, a notable addition to the subject of music on Greek pottery is the greatest of heroes Hercules. Late Archaic and Early Attic pottery often portray the hero with a kithara, and perhaps this symbolizes the association between physical and musical exercise which are necessary for a properly balanced education. Other great heroes such as Achilles, Theseus, and Paris are also sometimes portrayed playing a musical instrument (usually a lyre), once again reinforcing the dual aims of an aristocratic education and the virtue of music. Also, many school scenes on 5th century BCE pottery depict students with both a lyre and a book-roll, illustrating once again the importance of music in education. Finally, Lekythoi, slim jars for holding perfumes, are commonly found in grave contexts and often have music as the subject of their decoration, perhaps in an attempt to ensure that the deceased was accompanied by music on their journey into the next life.
About the Author
published by Kostas Kotsanas (26 June 2017)Currently unavailable
Cambridge University Press (18 January 2010)Price: $135.46
Cambridge University Press (23 June 2016)Price: $36.23
Clarendon Press (14 April 1994)Price: $89.16
Johns Hopkins University Press (01 April 1991)Price: $23.92
- Andrikou, E (ed), Gifts from the Muses (Hellenic Ministry of Culture, Athens, 2994)
- Anonymous, The Oxford Handbook of Hellenic Studies (Oxford University Press, USA, 2009).
- Kotsanas, K, THE MUSICAL INSTRUMENTS OF THE ANCIENT GREEKS (Kostas Kotsanas, 2013).
Cite This Work
Cartwright, M. (2013, January 05). Ancient Greek Music. Ancient History Encyclopedia. Retrieved from http://www.ancient.eu/Greek_Music/
Cartwright, Mark. "Ancient Greek Music." Ancient History Encyclopedia. Last modified January 05, 2013. http://www.ancient.eu/Greek_Music/.
Cartwright, Mark. "Ancient Greek Music." Ancient History Encyclopedia. Ancient History Encyclopedia, 05 Jan 2013. Web. 26 Jun 2017.
c. 5,000 BCEThe first aulos musical instruments are carved from bone.
2,700 BCE - 2,300 BCEThe first depiction in art of the aulos musical instrument appears in Cycladic sculpture.
1,420 BCE - 1,300 BCEClay dancing figures including a rare female lyre player are made in Minoan Palaikastro.
700 BCEThe study of music theory begins in ancient Greece.
c. 400 BCETheban musicians invent a more sophisticated aulos with metal keys.
c. 350 BCEAristoxenos writes his theory of music treatise 'Harmonic Elements'. |
Today, we're giving away a freebie! Here are some suggested activities based on Maurice Sendak's Where the Wild Things Are .
- Where does the forest, boat, ocean and indeed the place where the wild things are actually come from? What are some other places from stories that you know that may come from the same place?
- There are a number of exciting and fantastical wild things illustrated in the book. Create a ‘wild thing’ of your own and draw it. Perhaps the class can create a collage of wild things.
- Imagine that you were a wild thing. Create a frozen stature using your body and facial expressions to show the rest of the class what kind of wild thing you are. Get a number of other students to create a ‘sculpture garden’ full of statues of wild things they have created using just themselves.
- Write a story in which you visit the place where the wild things are and tell of your own adventure there.
- Imagine that Max didn’t go to the island where the wild things are. What other place might he have sailed to in his boat? What might he have found there and what adventures would he have had? |
Now that we've seen how electrons are bound to atoms, that they occupy orbitals with strict rules about how many atoms occupy what kind of odd-looking region around the nucleus, we're in a position to understand the layout of the periodic table. That understanding will help us to use the table as a tool for solving all kinds of problems, and for remembering facts that are easy to forget - the table will make it easy.
First let's have a look at the periodic table. Click on the one below to print it. I'll discuss some of its features below using smaller diagrams and pulled-out sections, so you might want to refer to the full table often.
The first thing that probably strikes you about the table is its odd shape. You've seen it before, but you've probably never understood why it's laid out like it is. It's all about the electron configurations. Take a look at this table, in which each element has been replaced by its electron configuration, to understand:
Look at the first (green) row in the table above. Hydrogen and Helium are elements 1 and 2, respectively, and have those numbers of electron (we always assume neutral atoms in the table). The electron configurations are H: 1s1 and He: 1s2. After that, the n=1 shell is full; it contains only an s-orbital and that can only hold two electrons. I've placed He over next to H in this table just to show that it lines up with all of the elements below it. We generally place it on the far right (like the first table) for another reason (I'll get to that later).
Now the blue row: Here the n=2 row is being filled. First the s-orbital is filled with two electrons (Li and Be), then across to the six p-orbital electrons, ending with Neon,
which has a full n=2 shell - no more electrons will fit into the n=2 shell. Notice that He, Ne and all of the atoms below Ne have full shells with increasing n. These atoms also happen to be the least reactive atoms in the table - food for thought.
Now the n=3 shell (magenta): First the 3s orbital is filled with two electrons (Na, Mg), then we skip over to the 3p orbitals, filling them until we get to Argon (Ar). What happens next is perfectly in keeping with the diagonal rule that we learned in the last section. First the 4s orbital, because it is of lower energy than the 3d orbitals, is filled (K and Ca), then we fill the 3d orbitals in the next row down.
The periodic table is arranged in order of orbital filling, according to the diagonal rule. The first two columns fill s-orbitals. The rightmost six columns fill p-orbitals. The middle group of ten fills the d-orbitals, and the Lanthanide and Actinide series (block below the main table) fill the f-orbitals.
The periodic table is just another expression of the diagonal rule of electron-orbital filling, and can be used to write the electron configuration of any atom, just by reading left-to-right, top-to-bottom.
Now we can address the issue of the relative stability of atoms. It was already noted that elements in the rightmost column of the table are especially non-reactive. In fact, their electrons are tightly bound and difficult to remove. Note that all of these atoms have eight electrons in their outermost (highest n) shell.
It is difficult in this section not to personify atoms, but it helps: Often it is said that atoms "want to have" eight electrons in their outer shell - the octet rule.
Nature always seeks the state of lowest energy. It's why a ball rolls downhill spontaneously, but never up. At right are the 1s, 2s and 2p orbital energies of a few atoms in the first and second rows of the table. Notice that as we add electrons the energies decrease (but remain in the same order). By the time we get to Neon, with 8 electrons in the n=2 shell, the atom so stable it is inert (doesn't react).
Another way of expressing the octet rule is to say that an atom tends to lose or gain electrons in order to have eight electrons in its outer shell, or full s- and p-orbitals. Note that the periodic table (and the diagonal rule) prescribe that the p-orbitals of any level are filled before its d-orbitals are filled.
The elements in the rightmost column of the table are called the inert gases. They all exist as gases at room temperature and they all have full outer-shell octets, which makes them unreactive (inert).
Columns in the periodic table are called groups, and rows are called periods. Elements in groups tend to have similar chemical properties (e.g. all gases, all inert).
Note that when the electron configuration gets cumbersome, it's OK to abbreviate the "core" configuration using another inert gas symbol, usually in [ ].
Now lets explore some of the other groups.
The second group from the right contains the Halogen group. These atoms all have seven electrons in their outer shells, one short of a full octet and a much lower energy.
As a result, these atoms tend to "steal" electrons from other atoms; they have a high electron affinity ("like" for electrons). Thus, the halogen atoms tend to exist as -1 ions, F-, Cl-, Br-, I- and At-.
Now we're getting somewhere. We've used electron configuration and its manifestation in the periodic table to find a whole group of atoms that exist mainly as -1 ions.
On to some other interesting and important groups. ...
The elements in the oxygen column are sometimes (not often) referred to as the chalcogens. They are usually just referred to as the oxygen group. They lack two electrons to have a full octet, so they tend to form -2 ions by picking up more weakly bound electrons from surrounding atoms.
These atoms tend to exist less as ions, however, and more as neutral atoms in molecules. There well be much more to say about this later.
Physically, the chalcogens are a mixed group: O is a gas, S is a nonmetallic solid, and Se - Po are metals. Polonium is radioactive, and found as the source of ionizing radiation in many smoke detectors.
The first column of the periodic table (the first group) is the Alkali metal group. This group contains the simplest element, Hydrogen.
The hallmark of this group is that the electron configuration of each element is that of the inert gas just "behind" it in the table, plus one electron in the next higher s-orbital.
Because there is so much energetic stability to be gained by losing this electron (more properly, having it taken by an atom with more of a need for a spare electron), these atoms tend to lose one electron to become a +1 cation.
The Hydrogen cation, H+, plays a crucial role in many chemical systems. Note that Hydrogen contains only a proton in its nucleus (except for its isotopes 2H, or deuterium, and 3H, or tritium). That means the Hydrogen cation is just a bare proton.
When you see an atom from the first group, you can be reasonably sure that it's a +1 ion in almost any context.
The Alkaline Earth elements have two electrons more than the next lower inert gas, two more than the most stable octet available, so they tend to lose two electrons to become more stable. Thus Alkaline Earths tend to exist mainly as +2 cations.
In one sense, Helium belongs in this group. We classify it over with the inert gases because it has a full n=1 shell, and because it is quite inert. Helium is directly involved in only a few rare chemical reactions.
In the next few sections we'll take a look at periodic trends that can be gleaned from the table. Often we can use the table to tell whether one element expresses more of some property than another just from the relative positions of the two in the table.
Elements within a group (column) of the periodic table tend to have very similar chemical properties. The properties of an element arise mainly from the outer-shell electron configuration.
In the periodic tables below, elements have been color coded to help you learn about some of the classifications of atoms. We'll start with the so-called standard states of elements, the state (solid, liquid or gas) likely to be found at room temperature and standard atmospheric pressure.
Most elements are solids. The lightest and most stable are gases, like the inert gases. Only bromine and mercury (Hg) are liquids, although some of the solid elements melt at fairly low temperatures.
The elements in this periodic table have been classified into six categories. Most elements have some kind of metallic character, which we'll define later. The metals in groups 1 and 2 tend to be soft and very reactive (some explosive when mixed with water!).
The transition metals are some of the best conductors of heat and electricity. The metalloids, which lie between metals and nonmetals, are interesting and very important because under the right conditions, they can be coaxed to have metallic or nonmetallic properties. This makes them particularly important in the electronics industry.
A relative handful of elements are key components of biological systems on Earth. Carbon, Nitrogen, Oxygen, Phosphorus, Sulfur and Hydrogen are the backbone atoms of all proteins, nucleic acids, carbohydrates and lipids.
Ions like Sodium and Magnesium are crucial electrolytes in and between cells, and many metals are essential cofactors of enzymes, without which enzymes can't work properly.
Cosmological theory tells us that at the beginning of the universe, the Big Bang if you will, mostly H and He were created. Fluctuations in the density of the expanding gases caused some regions to coalesce and create more of an attractive force on the atoms around them - gravity. As these areas became increasingly dense, compressed and hot, stars were formed. In the intense heat and gravitational pressure of stars, smaller elements are fused to create larger ones. Our own sun fuses atoms up to Iron, but mostly fuses Hydrogen atoms into Helium.
Any atom in our solar system larger than Iron, and probably quite a bit of what's here that's smaller,
had to come from other, hotter stars over the eons. Certain large elements can probably only be formed in the hottest stars, the supernovae.
Scientist and great science communicator, Carl Sagan, used to say that "we are all made of starstuff." All of the elements that compose us and our world came from stars, some unimaginably far away.
Below is a graph of the distribution of relative abundances of the elements in our solar system. Note that it's on a log scale, so for example, there is roughly ten times (101) the amount of H as He.
Source: Wikipedia Commons
In another section, we'll learn about other chemical trends that show up in the periodic table. We've only begun to get a feel for its usefulness. Keep yours with you and look at it once in a while. Keep it nearby when you do problems. Sleep with it. Talk to it. There are also a number of great periodic table apps available for your electronic devices.
Your chemistry teacher might disagree with me, so be careful here, but my view is this:
I ask my students to memorize the first ten elements of the table: H, He, Li, Be, B, C, N, O, F and Ne. These are the elements at the top of each column (group), and they are generally representative of the other elements in the group. If you know these elements, then you've got a framework on which to build a memory of the other elements in the group as you study chemistry. Before long you'll assimilate a lot more elements into your long-term memory and what gets stored there will make some logical sense.
For example, all of the noble gas elements (under He) are much more similar than different. It's a more productive way, in my view, to build a functional memory of the elements.
xaktly.com by Dr. Jeff Cruzan is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. © 2012, Jeff Cruzan. All text and images on this website not specifically attributed to another source were created by me and I reserve all rights as to their use. Any opinions expressed on this website are entirely mine, and do not necessarily reflect the views of any of my employers. Please feel free to send any questions or comments to email@example.com. |
Scientists have discovered vast water reserves near Earth’s mantle, a finding that could reshape our understanding of where Earth’s water came from.
According to a new study by a group of U.S. geophysicists, a reservoir of water three times the volume of all of Earth’s oceans has been discovered inside a layer of blue rock 440 miles deep.
Geophysicist Steve Jacobsen of Northwestern University, who coauthored the study, says it’s evidence the planet’s water bubbled up from somewhere underground.
The water is thought to be trapped in a layer of ringwoodite, a rock with a crystalline structure that acts like a sponge, to attract and trap the hydrogen and oxygen atoms that comprise water.
While the presence of this layer of ringwoodite hasn't be confirmed, there is mounting evidence that it exists. A chunk of diamond carried to Earth’s surface in a volcano earlier this year had a piece of ringwoodite inside.
Scientists used 2,000 seismometers to track the vibrations generated by earthquakes across the planet. The waves appeared to be propagating through saturated rock, rather than dry material, which gave scientists an idea of the size of the reservoir.
The scientists are trying to find out whether this reservoir layer extends around the whole planet. In the meantime, the results of the study thus far have been published in the journal Science. |
Welcome to Module 2 of the Energy Tutorial
Understanding how we use and pay for energy is fundamental if we’re going to save energy and carbon. This module will introduce the basics of energy usage, including energy used by lighting and appliances, different heating and hot water systems, energy meters, fuel bills and fuel payment methods. It will start to give you lots of ideas about how to save energy and how small changes can have a big impact!
Below you will find a number of factsheets, activities and videos that will introduce you to the basics of energy usage. Spend Week 2 of your volunteering going through these materials for one hour. Don’t worry if you don’t have time to look at them all, but do try to look at a mixture of factsheets, activities and videos. If you’ve volunteered as an Energy Envoy before, go through materials you didn’t look at last time or remind yourself of information you might have forgotten.
Make notes in your Activity Log or Learning Journal to record key points as you go.
The National Energy Foundation is not responsible for the content of external sites. Click here for more information.
The videos below explain energy used by appliances, top tips for saving energy and LED lights.
There is also a talk from Alex Laskey, who helps power companies to help their customers cut their energy use using data analysis, marketing and lessons from behavioural science. A lot of people already know how they can save energy, but still choose not to. Why is this? Because a range of social, cognitive and behavioural factors affect our decisions, meaning we don’t always make rational choices. Alex Laskey explains how understanding human behaviour can help us to persuade people to become wiser energy users with lower bills. |
Students formed groups of three or four and collected their materials. Each group received a disposable plate with three sections. The sections were labeled “prefix,” “suffix,” and “root word.” Finally, groups were given a bag of big words. They used scissors to cut the words into parts and drop each part into its respective section on the plate.
This is a fun activity to explore the science of balance and weight in the classroom. Have the students use the classroom balance scales to see how much items from their pencil boxes weigh. Does it weigh 1 bear, 2 bears, 3 bears, or more? Your students will have fun weighing their school supplies and recording their data! |
A stable climate is based on a long-term energy balance between the amount of energy that Earth receives from the Sun and the amount that Earth radiates back out into space. Any change in the atmosphere will ultimately result in a condition where Earth radiates the same amount of energy that it absorbs. However, the temperature, composition and circulation patterns of the air may all change to create that new equilibrium.
The Role of Carbon Dioxide
The normal level of carbon dioxide in the atmosphere during recent glacial and interglacial periods (last few hundred thousand years) has varied between approximately 180 ppm (parts per million) and 280 ppm. Since the beginning of the industrial revolution, this has risen more than 40% above the interglacial maximum, and is currently 400 ppm. Burning fossil fuels releases carbon dioxide into the atmosphere, and that amount of carbon dioxide can be measured. We (humans) are emitting more than 10 GT (giga-tons, billions of tons) of carbon into the atmosphere every year.
The Law of Conservation of Energy states that energy is never created or destroyed. This is the central pillar of all of science, and a principle that has been tested millions of times and confirmed without exception. As a consequence, for the climate of Earth to remain stable, with no changes in average temperatures, the total amount of energy absorbed by planet Earth from the Sun must be equal to the amount of energy Earth radiates back into outer space. If the energy received does not equal the energy radiated, the average temperature of Earth will necessarily rise or fall until a new equilibrium is established.
How does Earth change its equilibrium? The amount of energy radiated from Earth into outer space depends on the average temperature of the Earth. When the temperature is lower, Earth radiates less. When the temperature is higher, Earth radiates more. All objects do this. |
|Group:||Group IV ((+)ssRNA)|
An ECHO (enteric cytopathic human orphan) virus is a type of RNA virus that belongs to the species Enterovirus B, genus Enterovirus of the Picornaviridae family. Echoviruses are found in the gastrointestinal tract (hence it being part of the enterovirus genus) and exposure to the virus causes other opportunistic infections and diseases.
The first isolation of echoviruses occurred from the faeces of asymptomatic children early in the 1950s, just after cell culturing had been developed. The echo– part of the name was originally an acronym for "enteric cytopathic human orphan" virus: Orphan virus means a virus that is not associated with any known disease. Even though Echoviruses have since been identified with various diseases, the original name is still used.
Echovirus is highly infectious, and its primary target is children. The echovirus is among the leading causes of acute febrile illness in infants and young children, and is the most common cause of aseptic meningitis. Infection of an infant with this virus following birth may cause severe systemic diseases, and is associated with high infant mortality rates. The echovirus can mimic symptoms caused by other common bacterial and viral infections.
Viral structure and infection
An echovirus measures 24-30 nanometres (nm), and is similar to other viruses, since it has a naked protein capsid, which makes up 75% of the virus particle that encloses a dense central core of single-stranded RNA. This RNA has a length of approximately 7.5 kilobase (kb), contains an RNA replicase, viral-coded proteins, and a single polyprotein that is responsible for the formation of structural proteins and other proteins necessary for cellular replication. The structural proteins determine host range and play a very important role in delivering the RNA genome into the cytoplasm of new host cells.
Some viral replication of an echovirus occurs in the nasopharynx after infection and then spreads to regional lymph nodes. However, most viral particles are swallowed and they reach the lower gut tract, where the virus is presumed to bind to specific receptors. The virus then spreads to the lower intestinal tract, replicating but not causing any major cellular effects along the way. Next, the virus spreads to many secondary sites in the body such as the central nervous system, liver, spleen, bone marrow, heart and finally the lungs. Additional replication of the virus will occur, causing symptoms 4 to 6 days after infection. The most deadly part however is delayed when symptoms of a central nervous system disease start to appear. Enteroviruses are capable of infecting any cell in the body. These viruses are highly infectious. They can spread through the air to other hosts 1–3 weeks after infection and can spread through feces to other hosts eight weeks after infection.
Symptoms and diagnosis
Echovirus disease occurs disproportionately in males and children. Infection within the first two weeks of birth can cause devastating and potentially fatal disease. In this population, death usually results from overwhelming liver failure or myocarditis, rather than infection of the central nervous system. Older children and adults have a better prognosis. Myocarditis is the most frequent complication in adults.
Echovirus, like the other Enteroviruses Coxsackievirus A and B, typically causes a mild, nonspecific illness with a low fever. Echovirus may also produce a rash that spreads from the face down to the neck, upper extremities, and chest. Laboratory diagnosis is made with acute and convalescent titers of serum antibodies to Echovirus.
Cause of infection
Causes of echovirus infections (Acute meningitis) can be placed in several categories. Main causes of infection are from overcrowded conditions such as the poor districts of a city and poor hygiene. Echoviruses are transmitted person-to-person; the fecal-oral route is the predominant mode, although transmission sometimes occurs via respiration of oral secretions such as saliva. Indirect transmission occurs through numerous routes, including via contaminated water, food, and fomites (inanimate objects). Contaminated swimming and wading pools can also transmit the virus. Also, there are well-documented reports of transmission via the contaminated hands of hospital personnel.
No specific treatment for echovirus infection is currently available. Care is directed at relief of symptoms. The anti-viral drug pleconaril interferes with the binding of the echovirus particle to the cell membrane and the drug also hinders the uncoating of virions by attaching itself to the viral protein capsid. |
SAT Physics Subject Test
Chapter 10 Direct Current Circuits
RESISTANCE–CAPACITANCE (RC) CIRCUITS
Capacitors are typically charged by batteries. Once the switch in the diagram on the left is closed, electrons are attracted to the positive terminal of the battery and leave the top plate of the capacitor. Electrons also accumulate on the bottom plate of the capacitor, and this continues until the voltage across the capacitor plates matches the emf of the battery. When this condition is reached, the current stops and the capacitor is fully charged.
12. Find the charge stored and the voltage across each capacitor in the following circuit, given that ε = 180 V, C1 = 30 μ F, C2 = 60 μ F, and C3 = 90 μ F.
Here’s How to Crack It
Once the charging currents stop, the voltage across C3 is equal to the voltage across the battery, so V3 = 180 V. This gives us Q3 = C3V3 = (90μF)(180 V) = 16.2 mC. Since C1 and C2 are in series, they must store identical amounts of charge, and, from the diagram, the sum of their voltages must equal the voltage of the battery. So if we let Q be the charge on each of these two capacitors, then Q = C1V1 = C2V2 and V1 + V2 = 180 V. The equation C1V1 = C2V2 becomes (30μF)V1 = (60μF)V2, so V1 = 2V2. Substituting this into V1 + V2 = 180 V gives us V1 = 120 V and V2 = 60 V.The charge stored on each of these capacitors is
(30μF)(120 V) = C1V1 = C2V2 = (60μF)(60 V) = 3.6 mC
13. In the diagram below, C1 = 2 mF and C2 = 4 mF. When switch S is open, a battery (which is not shown) is connected between points a and b and charges capacitor C1 so that Vab = 12 V. The battery is then disconnected.
After the switch is closed, what will be the common voltage across each of the parallel capacitors (once electrostatic conditions are reestablished)?
Here’s How to Crack It
When C1 is fully charged, the charge on (each of the plates of) C1 has the magnitude Q = C1V = (2 mF)(12 V) = 24 mC. After the switch is closed, this charge will be redistributed in such a way that the resulting voltages across the two capacitors, V′, are equal. This happens because the capacitors are in parallel. So if Q′1 is the new charge magnitude on C1 and Q′2 is the new charge magnitude on C2, we have Q′1 + Q′2 = Q, so C1V′ + C2V′ = Q, which gives us |
The devastating fungus that has already killed more than one million US and Canadian bats continues to spread geographically, and to potentially threaten additional bat species.
The bat losses can have major impacts on ecosystems, since the flying mammals routinely consume large quantities of insects and themselves provide food and nutrients for other plants and animals. There also are economic impacts as caves continue to be closed to recreational use, in an effort to combat the spread of the disease.
In addition to the nine states with confirmed bat deaths noted in the April 29, 2009, TipSheet, so-called white-nose syndrome (named for the white fungal patches on the nose, muzzle, and wings of some infected bats) has been confirmed in Maryland, Missouri, Tennessee, Ontario, and Quebec. In addition, US Forest Service ecologist Susan Loeb, 864-656-4865, is predicting that it will soon spread to GA, KY, NC, and SC. She is also concerned that, along with six hard-hit species such as the Indiana bat and little-brown bat, it may well affect others, such as Virginia big-eared bats, small-footed bats, northern long-eared bats, Eastern pipistrelles, Rafinesque's big-eared bats, gray bats, and southeastern bats. Several of the at-risk species are listed as threatened or endangered.
- USFS press release, April 7, 2010: "Deadly Fungus Threatens 9 Bat Species in GA, KY, NC, SC and TN, Expert Says."
- The disease might eventually affect up to 25 of the 46 known US bat species, since those 25 species live in the cave and mine habitats that are home to the species decimated so far, according to Bat Conservation International: "Affected Species."
A concerted research effort on the causes and possible remedies continues, and the fungal species has been identified (Geomyces destructans), but much crucial information remains unknown (see the TipSheet noted above for many of these research organizations).
- The confirmation of a case in Missouri adds to the urgency felt by many researchers, since this is the first known incidence west of the Mississippi River, according to journalist Rinker Buck's April 20, 2010, story in the Hartford (CT) Courant, "Deadly Bat Fungus Appears To Be Spreading." The case is 300 miles from any other known case, indicating that a notable geographic barrier has been crossed, and eliminates another population of uninfected bats that could have been used as a control for research.
- The mysteries surrounding the disease, including how it is transmitted, have led to substantial economic impacts in many states as officials close caves to recreational use. That pattern continues in Missouri as officials there have announced the closure of many more government-controlled caves. However, in Missouri, as in some other states, many caves are in private hands, adding another layer of complexity to potential understanding and control of the disease. Kim McGuire covered both the cave closure and private cave issues in an April 20, 2010, St. Louis Post-Dispatch article, "Many Missouri Caves Will Close Over Bat Disease." |
By second grade, kids begin to better understand the physical world around them and, in turn, develop and intellectual curiosity to ask questions and learn more. Our science games for 2nd graders teach kids more complex scientific phenomena from matter to energy to weather and environment to the ecosystems that exist on our beautiful planet. If your second grade student is asking more questions about how our physical world operates, they will enjoy hours of endless learning through our 2nd grade science games. All of our science games on Turtle Diary are developed with colorful graphics and auditory sounds to create an online learning environment that is both interactive and engaging. We are confident your second grader will learn new and interesting science facts and spark an even deeper curiosity for the scientific world. Our science games for 2nd graders are perfect to play in school to reinforce concepts learned in the classroom, as well as at home for additional practice and pleasure. |
Following the British Calendar Act of 1751, Britain adopted the Gregorian Calendar in 1752. However, the current Julian calendar system required them to drop eleven days in order to sync themselves with the proposed Gregorian Calendar. So, on the evening of 2nd September 1752, the population of Britain and its American colonies went to sleep and awoke the next morning to 14th September 1752.
The changeover is also responsible for New Year’s Day being celebrated on 1st January, as before then it had been celebrated on 26th March.
As a result of Calendar Adjustment Day, there was rioting on the streets by those who felt cheated, and demanded the eleven days back! |
Your heart has four valves
- Mitral valve (left side)
- Aortic valve (left side)
- Tricuspid valve (right side)
- Pulmonary valve (right side)
Normally, these valves open to let blood flow through or out of your heart, and then shut to keep it from flowing backward. But sometimes they don’t work properly and the following may occur:
- Blood can leak back through the valve in the wrong direction, which is called regurgitation.
- The valve doesn’t open enough, which blocks blood flow, and this is referred to as stenosis (narrowing of the valve). Aortic stenosis is typically a disease of the elderly, as a buildup of calcium on heart valve leaflets occurs as one gets older.
- Atresia can occur if a heart valve lacks an opening for blood to pass through.
The mitral and tricuspid valves control blood flow between the ventricles and the atria. The pulmonary valve controls blood flow from the heart to the lungs and the aortic valve controls blood flow between the heart and the aorta, and ultimately the rest of the body. The mitral and aortic valves are most frequently affected by valvular heart disease due to the high pressure they experience.
Heart valve disease can make your heart work harder and affect its ability to pump blood. If not treated, advanced heart valve disease can cause heart failure, stroke, blood clots, or sudden death due to sudden cardiac arrest. You can be born with heart valve disease or develop it later in life. |
A periodic sentence is designed to be poetic and/or create suspense and anticipation because the full and completed meaning behind the sentence does not resolve until the very end of the sentence. With periodic sentences, the subordinate and dependent clauses come at the beginning and the independent clause will come at the end. A good example of this is "Over the river, and through the woods, To Grandmother's house we go." The first two phrases ("over the river" and "through the woods") are subordinate and dependent; they support the main idea, the independent clause, which is that "we go to Grandmother's house."
The first sentence of the second paragraph is a periodic sentence. "In the fall when the days became crisp and gray, and the long Minnesota winter shut down like the white lid of a box, Dexter's skis moved over the snow that hid the fairways of the golf course." The main idea (and independent clause) comes toward the end of the sentence. It is "Dexter's skis moved over the snow that hid the fairways of the golf course." This is a complete sentence by itself, but with the other two subordinate clauses in front of it, it becomes periodic.
The last sentence of the third paragraph is short but a perfect example of a periodic sentence because the main idea is completed with the final four words. "Without elation, without an interval of moist glory, the cold was gone."
In Part IV, the narrator notes "When autumn had come and gone again it occurred to him that he could not have Judy Jones." The main idea ("he could not have Judy Jones") is put at the end. The phrases before the main idea are subordinate. "When autumn had come and gone again" is subordinate and dependent. "It had occurred to him" is independent but subordinate to the main idea.
Again in Part IV, Dexter goes to visit Irene. "In the middle of May when the weather balanced for a few days on the thin bridge that led to deep summer he turned in one night at Irene's house." |
What do all chemical reactions have in common? Most students describe a chemical reaction as an event where an explosion, color change, or a gas is formed. As a prerequisite for this lesson students need only be acquainted with the particulate nature of matter. The main learning objective is the recognition that all chemical reactions create new molecules and that in a chemical reaction the original atoms get rearranged, bonding together in different ways. Overall, the lesson will take about 45-55 minutes. During the first two breaks, the class will list their preconceptions about chemical reactions and then experience an exciting reaction which is produced inside a re-sealable plastic bag. The chemicals needed for this reaction are sodium bicarbonate and calcium chloride. After this excitement, the video will show how to separate the mixture to demonstrate the existence of the new products, which include sodium chloride, CO2 and chalk. The separation can be completed by the classroom teacher as well at a later time. In the third break, the teacher will write out the balanced chemical equation and the class will account for the same number of atoms on each side of the equation, demonstrating the conservation of mass. In the fourth break, students will have time to model the atoms chemical reaction using LEGO® bricks as the atoms or by using atoms made from clay or homemade play dough. Lastly, the video will apply the definition of chemical reaction to analyze a scene where a cork explodes from a heated liquid in a test tube.
For more information, visit: http://blossoms.mit.edu/videos/lessons/recognizing_chemical_reactions |
Making Bricks and Pavers – These slides will take you on a step by step journey through the manufacturing process of our bricks and pavers.
Alternatively you can watch our short film here:
From piles of dry clay, through the mixing process, the extrusion process, cutting, trimming, and through to firing.
To produce a clay brick the raw materials are first crushed and ground. Natural clay minerals, including kaolin and shale, make up the main body of brick. Small amounts of manganese, barium, and other additives are blended with the clay to produce different shades, and barium carbonate is used to improve brick’s chemical resistance to the elements.
Then the ingredients are formed using the extrusion method. The pulverized ingredients are mixed togther with water, passed into a de-airing chamber (which removes the air to prevent cracking), compacted, and extruded out of a die of the desired shape.
A wide variety of coating materials and methods are used to produce brick of a certain color or surface texture such as sand of a glaze.
Once the bricks are formed they are dried to remove excess moisture that might otherwise cause cracking during the ensuing firing process.
Next, bricks are loaded onto carts and moved into large furnaces called kilns.
The bricks are fired in a high temperature kiln and then cooled.
Firing hardens and strengthens the brick. After firing they are left to cool.
Finally, they are hand graded, stacked, and wrapped on pallets. |
When you cut and burn a tropical forest, you’re left with a barren plain of cracked red mud, incapable of supporting life – the opposite of the teeming, hyperdiverse array of life that was destroyed. Once the trees are gone, the nutrients wash away and the soil degrades into a dense, brick-like layer so hardened that plant roots can’t get through it.
This was the vision of tropical deforestation held in the popular imagination for many years, but the reality is more complex – and more hopeful.
In recent decades, researchers have found that tropical forests are remarkably resilient. As long as some remnants are left when the forest is cleared to provide seeds and refuges for seed dispersers, tropical forests can grow back with astonishing speed.
In a paper published this week in Nature, lead author Lourens Poorter and a team of international collaborators, including me, found that forests in Central and South America can quickly rebound without human intervention on land that has been cleared for cattle grazing or growing crops.
This finding has important implications for climate change because these so-called secondary forests soak up large amounts of carbon from the atmosphere, even without costly reforestation efforts. These regenerating forests are also crucial for protecting biodiversity and all the ecological and social benefits it provides.
Tropical secondary forests – that is, forests that grow after a major clearing, such as a fire, farming or logging – cover an increasing part of the globe. And as their extent expands, so does their potential to shape conservation strategies, both at the local and global scales.
At the U.N. Climate Summit in 2014, 30 nations and a host of NGOs and private companies endorsed the New York Declaration on Forests, a document that advocates halving deforestation by 2020 and ending it completely by 2030.
One of the key points of the declaration calls for the restoration of 150 million hectares (about 375 million acres) of degraded forest land by 2020 and additional restoration in the following decade.
But active forest restoration can be an expensive process, and it may not be cost-effective or even necessary in every case. In landscapes with low levels of degradation, simply protecting young forests and allowing them to develop may be the best strategy.
In our research, my colleagues and I present the largest data set yet assembled to investigate forest regrowth in the New World tropics. The data set spans 45 sites in the lowland tropics from wet forest to dry forest, with a total of 1,478 plots and more than 168,000 individual trees.
It offers an unprecedented, and more hopeful, view of forest recovery.
According to this analysis, tropical secondary forests have enormous potential for removing carbon from the atmosphere. The net carbon uptake for these secondary forests is 11 times that of old-growth forests in the region we studied.
The rate of biomass recovery varies widely across the region, with the fastest regrowth in areas with high rainfall. The median time for a forest to reach 90 percent of old-growth biomass levels was 66 years, but recovery can be much faster in some areas.
Big win for biodiversity
It shouldn’t come as a surprise that tropical forests can grow back after major disturbances. Tropical forests can be affected by a number of different large-scale natural disasters like floods, fires, landslides, major storms and volcanic eruptions.
Even old-growth tropical forests are highly dynamic systems, marked by cycles of tree death and regrowth. The mortality rates for trees larger than 10 centimeters in diameter have been estimated at one percent to two percent per year for forests in the Amazon and Central America. In other words, at the upper end, one in every 50 large trees will fall in the course of a given year.
The gaps in the forest that result from treefalls are rapidly colonized by a riot of vines and fast-growing tree saplings. The heterogeneity of habitats produced by this cycle is a major driver of tropical diversity.
In addition, the history of human-induced disturbances in tropical forests is longer and more complex than we often acknowledge.
Legacies of ancient human use, stretching back for millennia, have been detected in nearly every “pristine” tropical forest on earth: massive earthworks in the Amazon and modern-day Cambodia; charcoal and pottery fragments in the Congo Basin; and evidence of forest clearing going back nearly 50,000 years in Papua New Guinea.
Indeed, various forms of slash-and-burn cultivation have been practiced for millennia throughout the tropics.
As long as the cleared areas are modest in size and the period between cycles of cultivation is sufficient for recovery, diverse forests can persist for thousands of years.
Local and global benefits
Tropical secondary forests can – and should – form a substantive part of the long-term global strategy to combat carbon emissions and preserve biodiversity for the future.
Our recent research shows, for example, that in areas where biomass recovery is slow – like the tropical dry forest – we should prevent further forest loss. Where recovery is rapid, we can combine old-growth forest conservation with policies that promote secondary forest formation.
Shifting focus to the conservation of regenerating forests should not take away from the urgent imperative to conserve the remaining uncut tropical forest.
The clearing of old-growth tropical forests is a major source of human-induced greenhouse gas emissions, second only to fossil fuel combustion. Clearly, keeping the carbon that’s currently stored in intact tropical forests from being released to the atmosphere should be a priority.
Old-growth tropical forests also harbor immense biological diversity – including genetic diversity – and if all of the remaining old-growth forests in a landscape are cut, there will be no seed source to promote regeneration.
Conserving secondary forests offers a different, and complementary, set of benefits.
As well as their massive potential for taking up carbon as they grow, secondary forests provide resources and livelihoods for the people who inhabit them.
Secondary forests can harbor a high diversity of ethnobotanically important species that can be used for medicines. They can serve as extractive reserves, where limited harvesting of timber, game animals and other forest products will prevent the exploitation of resources in vulnerable protected areas. They protect watersheds and prevent erosion.
As secondary forests grow back, they eventually come to resemble the forest that was cut, and in the meantime, they knit together the remaining fragments of forest into a more contiguous landscape.
As David Quammen wrote in “Song of the Dodo (1997),” isolated populations of organisms in forests lose connections to the resource base that supports them. Over generations they lose their genetic diversity, making them more vulnerable to inbreeding, disease, and eventual extinction.
Secondary forests offer the hope of reconnecting habitats and creating a more resilient landscape for the future.
So harnessing the power of forest regeneration in the tropics will have benefits both locally – providing resources and restoring ecosystem services – and globally, by sequestering carbon from the atmosphere.
At the Paris Climate Summit, leaders took important steps toward halting deforestation. Promoting forest regrowth is another vital piece of the equation. It’s time for policymakers to recognize the benefits that tropical secondary forests provide, and to shape policies that take advantage of this enormous potential. |
Seasonal Affective Disorder is a Major Depressive Disorder experienced by people who have normal mental health throughout most of the year, but experience depressive symptoms in the winter or, less frequently, in the summer, spring or autumn, repeatedly, year after year. Usually, seasonal affective disorder symptoms appear during late fall or early winter and go away during the sunnier days of spring and summer. Some people have the opposite pattern and become depressed with the onset of spring or summer. In either case, problems may start out mild and become more severe as the season progresses.
Just as sunlight is known to affect the seasonal activities of animals (i.e., reproductive cycles and hibernation), SAD is believed to be an effect of seasonal light variation in humans. As the seasons change, it is suggested that there is a shift in the “biological internal clocks” or circadian rhythm, due partly to these changes in sunlight patterns. It is this shift that is believed to cause the biological clocks to be out of “step” with the daily schedule, resulting is Seasonal Affective Disorder.
Symptoms for SAD are similar to those for atypical depressive illness such as hypersomnia (increased sleep), increased appetite with carbohydrate cravings, weight gain and profound fatigue. Younger individuals, particularly women, appear to be at higher risk for SAD.
Researchers have long sought to locate the biochemical sources of this disorder. It has been discovered that the pineal gland, located in the middle of the brain, responds to darkness by secreting melatonin, which re-sets the brain's central clock and helps the light/dark cycle re-set the sleep/wake cycle and other daily rhythms. To further evaluate this, researchers (Lewy et al, 2006) tracked sleep, activity levels, melatonin rhythms and depression symptoms of 68 SAD patients who took either low doses of melatonin or a placebo in the morning or afternoon for a winter month when they were most symptomatic. They had previously determined from healthy subjects that a person's rhythms are synchronized when the interval between the time the pineal gland begins secreting melatonin and the middle of sleep is about 6 hours. They found that seventy-one (71) percent of the SAD patients had intervals shorter than 6 hours, indicating that their rhythms were delayed due to the later winter dawn. Taking melatonin capsules in the afternoon lengthened their intervals, bringing their rhythms back toward normal. The closer their intervals approached the ideal 6 hours, the more their mood improved on depression rating scales, supporting the hypothesized link between out-of-sync rhythms and SAD.
Apart from melatonin supplements, treatment for SAD also includes bright light treatment. For this treatment, the person is required to sit in front of a "light box" for half an hour or longer, usually in the morning. Another useful treatment is called dawn simulation. For this treatment, a dim light goes on in the morning while the person sleeps, and it gets brighter over time, like a sunrise. Treatment for SAD can also include antidepressants which have been shown to be effective in the treatment of SAD. Finally, psychotherapy, in conjunction with the above, has resulted in improved overall coping for sufferers of SAD.
Those believed to be suffering from SAD should seek professional consultation to obtain an accurate diagnosis and to rule out other causes for the depressive symptoms. |
Music is full of gestures: an action or sound that is going somewhere.
We will explore and learn how we can use them in our own compositions.
What Is a Gesture?
Gestures go from point A to point B. These might be up, down, left, right, quiet, loud, around in a loop, etc. or any combination of these.
The basic point is that they begin somewhere and end somewhere else.
Defining a Gesture
Gesture in sound is difficult to define because it comes from all aspects of sound (a bit like TimbreThe colour or quality of a sound. A combination of all other properties that makes each sound unique. timbre/sound quality). It can be found within traditional pitch-based music, or even in individual sounds themselves.
A single sound might be a gesture.
This is a single gestural sound.
OR it might be made up of a number of sounds.
This glugging sound contains a number of individual 'glug' gestures, but each glug is also part of a larger 'glugging' gesture.
Gestures might also occur within a single sound, for example, as a swell.
This sound is made up of many small grains, but the gesture is in the overall shape of the sound, as it fades in and then back out again.
Gesture and Dance
It might be useful to think about gesture in terms of movement, such as within dance. When people dance they react to the music, physically moving their body. When they move, they are responding to the sound gestures within the music. Often this will be the pulsating gestural rhythm of the bass or drums, but might also be the melody.
Gesture in the Voice
We also use gestures within our voice to communicate. If we listen to a language that we don’t understand, we can sometimes still work out how the speaker is feeling (and perhaps even some of their message) by listening out for the gestures in their voice.
Take a simple statement: ‘I love puppies’.
Everyone will read this out loud in a different way; it is even possible for the same person to read it in many different ways. The way in which the statement is spoken might even change the meaning.
Experiment with saying the above statement (‘I love puppies’) in as many different ways as you can. Try to identify what particular properties of the spoken statement affect the way that it sounds, and whether these affect how the phrase is understood.
You can change the pitch, speed and phrasing to create new gestures. Try starting at a high pitch and ending low, OR starting at a low pitch and ending high.
Gestures in Sounds
Sounds themselves can be gestural. Often, the gesture within the sound is related directly to the way in which it is performed. For example, hitting a cymbal hard will produce a different sound compared to lightly tapping it.
Practice with creating sounds can help us to listen out for, and recognise, gestures within sounds.
Select actions from the following list which you can perform. Experiment with the way that you are able to perform the actions, and listen to the sound gestures that are created. Which are the most impressive gestures? Are some sounds more textural than gestural?
How can you change the way that you create the sounds in order to modify the gesture? Think about trying different speeds, different sizes and changing the volume.
Present your selection of actions to others, and explain to them how the sound gestures that you created are connected to the way in which you perform them.
Click here for the FULL LIST of words
Full List of Actions
- Tear off
- Fall down
- Touch lightly
- Drum fingers
Gestures might be thought of as the opposite of textures.
Denis Smalley described how gestures enhance the impression of time passing.
So, if you want to give the impression of forward motion within a composition, then you could try to use many gestural sounds.
DENIS SMALLEY (1997). Spectromorphology: explaining sound-shapes. Organised Sound, 2, pp. 107-126. |
The advent of the Khalji dynasty marked the zenith of Muslim imperialism in India. The founder of the Khalji dynasty was Jalaluddin Khalji. He was seventy years old when he came to power. He was generous and lenient. Malik Chhajju, nephew of Balban was allowed to remain the governor of Kara. His leniency was misunderstood as weakness. When Chhajju revolted, it was suppressed but he was pardoned. When the thugs (robbers) looted the country, they were allowed to go after a severe warning. In 1292 when Malik Chhajju revolted for the second time, he was replaced by his son-in-law, Alauddin Khalji.
In 1296 Alauddin Khalji took an expedition to Devagiri and returned to Kara. During the reception there, Alauddin Khalji treacherously murdered his father-in-law Jalaluddin Khalji and usurped the throne of Delhi.
Alauddin Khalji (1296-1316)
Alauddin Khalji made enormous gifts to the hostile nobles and Amirs of Delhi to win over them to his side. Those who still opposed him accession were punished severely. He framed regulations to control the nobles. He was convinced that the general prosperity of the nobles, intermarriages between noble families, inefficient spy-system and drinking liquor were the basic reasons for the rebellions. Therefore, he passed four ordinances. He confiscated the properties of the nobles. The intelligence system was reorganized and all the secret activities of the nobles were immediately reported to the Sultan. The public sale of liquor and drugs was totally stopped. Social gatherings and festivities without the permission of Sultan were forbidden. By such harsh measures his reign was free from rebellions.
Reforms of Alauddin Khalji
Alauddin Khalji maintained a large permanent standing army and paid them in cash from the royal treasury. According the Ferishta, he recruited 4,75,000 cavalrymen. He introduced the system of dagh (branding of horses) and prepared huliya (descriptive list of soldiers). In order to ensure maximum efficiency, a strict review of army from time to time was carried out.
The introduction of paying salaries in cash to the soldiers led to price regulations popularly called as Market Reforms. Alauddin
Khalji established four separate markets in Delhi, one for grain; another for cloth, sugar, dried fruits, butter and oil; a third for horses, slaves and cattle; and a fourth for miscellaneous commodities. Each market was under the control of a high officer called Shahna-i- Mandi. The supply of grain was ensured by holding stocks in government store-houses. Regulations were issued to fix the price of all commodities. A separate department called Diwani Riyasat was created under an officer called Naib-i-Riyasat. Every merchant was registered under the Market department. There were secret agents called munhiyans who sent reports to the Sultan regarding the functioning of these markets. The Sultan also sent slave boys to buy various commodities to check prices. Violation of regulations was severely punished. Harsh punishment was given if any shopkeeper charged a higher price, or tried to cheat by using false weights and measures. Even during the famine the same price was maintained.
We are not sure whether the market regulations in Delhi were also applied in the provincial capitals and towns. Apart from market reforms, Alauddin Khalji took important steps in the land revenue administration. He was the first Sultan of Delhi who ordered for the measurement of land. Even the big landlords could not escape from paying land tax. Land revenue was collected in cash in order to enable the Sultan to pay the soldiers in cash. His land revenue reforms provided a basis for the future reforms of Sher Shah and Akbar.
Alauddin Khalji sent his army six times against the Mongols. The first two was successful. But the third Mongol invader Khwaja came up to Delhi but they were prevented from entering into the capital city. The next three Mongol invasions were also dealt with severely. Thousands of Mongols were killed. The northwestern frontier was fortified and Gazi Malik was appointed to as the Warden of Marches to protect the frontier. The military conquests of Alauddin Khalji include his expedition against Gujarat, Mewar and the Deccan. He sent Nusrat Khan and Ulugh Khan to capture Gujarat in 1299. The king and his daughter escaped while the queen was caught and sent to Delhi. Kafur, an eunuch, was also taken to Delhi and later he was made the Malik Naib – military commander. Then in 1301, Alauddin marched against Ranthampur and after a three month’s siege it fell. The Rajput women committed jauhar or self-immolation.
Alauddin next turned against Chittor. It was the powerful state in Rajasthan. The siege lasted for several months. In 1303 Alauddin stormed the Chittor fort. Raja Ratan Singh and his soldiers fought valiantly but submitted. The Rajput women including Rani Padmini performed jauhar. This Padmini episode was graphically mentioned in the book Padmavath written by Jayasi.
Alauddin Khalji’s greatest achievement was the conquest of Deccan and the far south. This region was ruled by four important dynasties – Yadavas of Devagiri, Kakatiyas of Warangal, Hoysalas of Dwarasamudra and the Pandyas of Madurai. In Alauddin sent Malik Kafur against the ruler of Devagiri, Ramachandra Deva, who submitted and paid rich tributes.
In 1309 Malik Kafur launched his campaign against Warangal. Its ruler Pratabarudra Deva was defeated and enormous booty was collected from him. Malik Kafur’s next target was the Hoysala ruler Vira Ballala III. He was defeated and a vast quantity of booty was seized and sent to Delhi. Kafur next marched against the Pandyas. Vira Pandya fled the capital Madurai and Kafur seized enormous wealth from the Pandya kingdom and returned to Delhi. Alauddin Khalji died in 1316. Although the Sultan was illiterate, he patronized poets like Amir Khus
rau and Amir Hasan. He also built a famous gateway known as Alai Darwaza and constructed a new capital at Siri.
Mubarak Shah and Khusru Shah were the successors of Alauddin Khalji. Ghazi Malik, the governor of Dipalpur, killed the Sultan Khusru Shah and ascended the throne of Delhi under the title of Ghiyasuddin Tughlaq in 1320. |
History is a disciplined process of inquiry into the past that helps to explain how people, events and forces from the past have shaped our world. It allows students to locate and understand themselves and others in the continuum of human experience up to the present. History provides opportunities for students to explore human actions and achievements in a range of historical contexts. Students become aware that history is all around us and that historical information may be drawn from the physical remains of the past as well as written, visual and oral sources of evidence.
The study of History from Kindergarten to Year 10 investigates the actions, motives and lifestyles of people over time, from individuals and family members, to local communities, expanding to national and world history contexts. It introduces the idea that History contains many stories and that there is never only one uncontested version. There are many differing perspectives within a nation's history, and historians may interpret events differently depending on their point of view and the sources they have used. The study of History strengthens an appreciation for and an understanding of civics and citizenship. It also provides broader insights into the historical experiences of different cultural groups within our society and how various groups have struggled for civil rights, for example Aboriginal and Torres Strait Islander peoples, migrants and women. History encourages students to develop an understanding of significant historical concepts such as cause and effect, change and continuity, significance, empathy and contestability.
History as a discipline has its own methods and procedures. It is much more than the simple presentation of facts and dates from the past. History provides the skills for students to answer the question 'How do we know?' An investigation of an historical issue through a range of sources can stimulate curiosity and develop problem-solving, research and critical thinking skills. It develops language specific to the discipline of History and provides opportunities to further develop literacy skills. Students learn to critically analyse and interpret sources of evidence in order to construct reasoned explanations and a rational and informed argument based on evidence, drawn from the remains of the past. Students engage in research involving traditional methods and ICT, including evaluating web-based sources and using a range of technologies for historical research and communication. |
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Joshua Tree National Park - Park Geology
Rockpiles and IntrusionsThe geologic landscape of Joshua Tree has long fascinated visitors to this desert. How did the rocks take on such fantastic shapes? What forces sculpted them?
Geologists believe the face of our modern landscape was born more than 100 million years ago. Molten liquid, heated by the continuous movement of the Earth's crust oozed upward and cooled while still below the surface. These plutonic intrusions are a granitic rock called monzogranite.
The monzogranite developed a system of rectangular joints. One set, oriented roughly horizontally, resulted from the removal, by erosion, of the miles of overlying rock, called gneiss. Another set of joints is oriented vertically, roughly paralleling the contact of the monzogranite with its surrounding rocks. The third set is also vertical, but cuts the second at high vertical angles. The resulting system of joints tended to develop rectangular blocks. Good examples of the joint system may be seen at Jumbo Rocks, Wonderland of Rocks, and Split Rock.
As groundwater percolated down through the monzogranite's joint fractures, it began to transform some hard mineral grains along its path into soft clay, while it loosened and freed grains resistant to solution. Rectangular stones slowly weathered to spheres of hard rock surrounded by soft clay containing loose mineral grains. Imagine holding an ice cube under the faucet. The cube rounds away at the corners first, because that is the part most exposed to the force of the water. A similar thing happened here, but over millions of years, on a grand scale, and during a much wetter climate.
After the arrival of the arid climate of recent times, flash floods began washing away the protective ground surface. As they were exposed, the huge eroded boulders settled on top of one another, creating those impressive rockpiles we see today.
Visitors also wonder about the "broken terrace walls" laced throughout the boulders. These are naturally occurring formations called dikes or intrusions. Younger than the surrounding monzogranite, intrusions were formed when molten rock was pushed into existing joint fractures. Light-colored intrusions formed as a mixture of quartz and potassium minerals cooled in these tight spaces. Suggesting the work of a stonemason, they broke into uniform blocks when they were exposed to the surface.
Of the dynamic processes that erode rock material, water, even in arid environments, is the most important. Wind action is also important, but less so than the action of water.
The processes of operating in the conditions of the present are only partially responsible for the sculpting of the rocks. The present landscape is essentially a collection of relic features inherited from earlier times of higher rainfall and lower temperatures.
Geology tour road
Granitic rock formation in the Mojave Desert
Horizontal and vertical joints in monzogranite formation.
Boulders forming have not net broke free of formation.
Quartz intrusion into monzogranite (dike). |
In our last blog and reading of the year, the second part of the eleventh chapter of The Fabric of the Cosmos” was covered. In this part of The Fabric of the Cosmos, the book talks about a period of our universe’s life that the book calls the “fuzzy patch.” This fuzzy patch that the book is referring to is a period very early in our galaxy’s life that we are unable to observe. This period of time would give us vital information that would increase our understanding of the inflationary era greatly. The book says that this time period is characterized by extreme heat and extreme density.If we could observe our universe under these conditions, we could understand much more about our universe and potentially turn the theory of inflation into a fact of our universe.
In Chapter eleven of The Fabric of the Cosmos, the question, “How did galaxies form as a result of a completely uniform universe?” is answered. The book says that although our universe was uniform in the beginning of time, it was not completely and perfectly uniform. There was a tiny lumpiness that eventually grew larger and became the galaxies that we observe today. Buy why was there this tiny lumpiness before our galaxies were formed? The book attributes these tiny lumps in our early universe as being a result of quantum mechanics. The idea idea of uncertainty that comes along with quantum mechanics is what caused these disturbances, or as the book calls them, “jitters.” These jitters are still present and are constantly occurring in today’s galaxy. The book says that these minor jitters that occur in our galaxy could perhaps even result in other universes being created and give substance to the theory of parallel universes. I think that these jitters give the idea of parallel universes some substance and make this theory of parallel universe more believable.
In chapter ten of The Fabric of the Cosmos, the idea of inflation is first presented by Greene to the readers. He first explains the idea of inflation by comparing it to a frog perched on top of a plateau in a bowl. Just like he universe, the frog will quickly move away from the plateau and towards the bottom of the bowl. In comparison to the universe, the bottom of the bowl is equivalent to a lower energy state of the universe. The universe will naturally progress towards a state of less energy compared to the state that our universe was in before the Big Bang.
In an incredibly small amount of time the universe expanded from the size of a strand of DNA to the size of the Milky Way galaxy. The extreme increase in the expansion of pace was the exact moment that happened after the Big Bang. After the initial outburst, the expansion of space has slowed down to a more steady pace. Will the end of the universe be a reverse of the Big Bang? This section suggests that that could potentially be true, but I later in the book I learned that this is not true. What I later found out, extraordinarily, is that the universe is actually speeding up in its expansion.
Chapter nine of the Fabric if the Cosmos deals with the relationship between temperature and symmetry in our universe. The book states that the universe and cosmos in general has gone through phase transitions similar to those that happen when water turns in to ice. These changes that have happened as our universe gets larger are a result of the decreasing temperature in our universe and also account for a decrease in the symmetry of our universe. One of the most interesting topics of this chapter of the Fabric of the Cosmos was the idea of a graviton- an actual particle that portrays the characteristics if gravity. Is there a connection between gravity’s elusive particle,the graviton, and the unusual and generally weak force exhibited by gravity? I think that there is a definite possibility that there is considering the fact the gravity is the most mysterious of all forces to us.
The third section of chapter eight of The Fabric of the Cosmos deals with the relationship between space-time and the symmetry of the universe. When a person looks at something in the universe, he is looking through both space and time. because this observer is looking into the past, one would assume that we could look back far enough so that we could observe the Big Bang. This is not the case, in the books diagram, the closer we get to the Big Bang, the fuzzier the observation becomes. On the assumption that both space-time exists and the inflation of the universe originated at the Big Bang we can learn more about what actually did happen in the first moments of the universe. The universe must have exponentially expanded in the exact moment that the Big Bang occurred. The book says that instead of the Big Bang happening at one location, it must have happened everywhere. This concept is difficult for me to wrap my mind around because I would have thought that the Big Bang originated at a single point. However, this new thought that the Big Bang happened everywhere in the universe at once ames much more sense when completely thought through. This thought agrees with the inflation that we learned about in this chapter and also agrees with the current model of space-time that we have.
This second part of chapter eight in The Fabric of the Cosmos deals with the stretching of space. We know that the universe has been expanding ever since the Big Bang. When observing the universe and the speeds at which things are moving away from earth, it appears that the earth was the region from which the Big Bang started. The book explains this view by saying that the universe is stretching. Earth is not actually the point from which the Big Bang started, rather because of the way in which the universe is stretching, the universe appears to be expanding away from one’s point wherever that person is in the universe. The book compared this stretching mddl of the universe to an expanding balloon with pennies on it. This stretching of the universe further develops my concept of the symmetry of the universe. The universe seems more likely to be symmetric in this expanding model, with time being the only asymmetric part of the universe.
This section of The Fabric of the Cosmos dealt with the symmetry of space. The section calls everything that has existed in space since the big Bang symmetric. This symmetry is so common throughout our universe because symmetry is just a part of time. The book compares the symmetry of space to looking at a snowflake or other object from different angles. The snowflake would look the same for many of the angles that one looked an the snowflake, but not all the ways you look at the snowflake. The question becomes, when relating this theory to our universe, in which ways that we look is are universe symmetric compared to not symmetric? One of the ways that our universe is not completely symmetric is time. As the time moves forward in the universe, things change. If the universe were completely symmetric time would not even exist because there would be no way of recognizing that time is passing. Basically everything would be the same forever. |
Learn how to successfully meet the diverse needs of students with disabilities in your classroom from an experienced special educator. We'll dissect the whole special education process, from working with individualized education programs (IEPs) to helping students struggling with reading comprehension, math skills, and writing.
We'll also talk about fun games you can incorporate, tips for modifying your classroom, and lots of tested methods for bringing out the best behavior in your students. Whether you're already in the classroom, studying for the Praxis Special Education exam, or getting ready to work with students in a variety of settings, this course will prepare you to understand and empower your kids with learning disabilities. In this course, you'll discover easy, practical, and creative strategies that will help your struggling students find their light bulb moments! |
Morphemes often provide valuable information with respect to the pronunciation of a word. They can also assist linguists with syllable division.
For example, the two English words "finger" and "singer" have different word-initial segments, but this is not the sole difference. The word "singer" consists of two morphemes, the verb "sing" and the agentive suffix -er. The verb "sing" ends with a velar nasal which is also present in "singer". This word consists of five segments or four if one analyzes the -er suffix as a syllabic r or schwar (r-coloured vowel) in which case it has only four. Since no English syllable can begin with a velar nasal, it is clear that singer can be divided as sing + er. The word, finger, however, is different. This word consists of a single morpheme. The "n" is a velar nasal but it is followed by a voiced velar plosive. The word finger consists of six segments or five if one analyzes -er as a syllabic r or schwar (r-coloured vowel). It appears that the only reason "singer" does not have a velar nasal followed by a velar plosive is due to the lack of a velar plosive in the bound morpheme "sing".
In the Spanish word "monstruo" meaning monster, we see a sequence of four consonants in word-medial position. The "u" is pronouned as a "w", a labiovelar glide. Such a consonant sequence does not occur word-initially nor word-finally in Spanish words. Since the consonant sequence -ns does not occur word-finally and -str does not occur word-initially, it is unclear how to divide the two syllables. However, the -ns sequence does occur in proper nouns such as the last name "Sanz" (pronounced with a voiceless dental fricative or voiceless interdental fricative in Castilian Spanish), thus providing evidence for the syllable division mons + truo. A number of Spanish words begin with the consonant sequence tr- such as "tren" (train), "tratamiento" (treatment) and "trono" (throne).
When it is unclear how to syllabify a particular word, evidence from other words can be very useful. In the case of pronunciation, a language may favour a particular pronunciation to remain faithful to the pronunciation of a particular morpheme prior to affixation. |
Tropical depressions are relatively minor tropical cyclones. They are not as intense as tropic storms, which are not as intense as hurricanes. Over time, however, tropical depressions can become stronger storms.Continue Reading
Tropical cyclones are low-pressure areas over the ocean. Over time, they can become more organized and more intense. Potential storms are referred to as tropical disturbances. Once they become more defined, they are classified as tropical depressions.
Tropical depressions have winds of less than 34 miles per hour. Above that speed, they are called tropical storms. They do not typically have the characteristic eye wall of more intense storms, but they can show some signs of rotation. Experts can generally predict which storms will intensify and which will dissipate.
Names are not given to tropical depressions, but some media outlets might give them a name prematurely. However, storms are given a name once they become tropical storms and those that degrade back to tropical depressions will keep their names. Tropical depressions are not as intense as some small storms that form on land or near land and they generally do not cause much damage from their winds. However, they are large and the sheer volume of rain they drop can cause a range of problems.Learn more about Weather & Tides |
HEXAGON: An Aid in Remembering the Eight Fundamental Trigonometric Identities
Trigonometry is one of the oldest branches of mathematics, not by name, perhaps, but in its application to the measurement of distances, heights, depths, areas, and volumes. In the early centuries, the seasons of the year and the hours of the day are indicated by shadows cast by an upright pole, tree or rock. A tree or other upright objects which casts a shadow for this purpose was called by the Greeks a gnomon (which means inspector) and the shadow was called an umbra, Latin for shadow. When the umbra is longest at noon, thus it is called the winter solstice; whereas when shortest, it is called the summer solstice, usually occurring during the month of June.
Other notable evidences of the use of the triangle in measurement are found in sundials used to measure or indicate the time of the day. These sundials were commonly used a few centuries ago and some are still being used in some oriental countries.
As means of measurement, trigonometry seems to have developed very early in Asia, specifically in India, Iraq, Egypt, and China. Some traces appear about 4, 000 years ago, generally in the surveying of land, the planning of irrigation ditches and the determination of the height of edifices (as in the case of the Pyramid at Khafre, Egypt).
As a science, it is to the Greeks, at one time the most scholarly of the ancient peoples of the Mediterranean region that trigonometry owes its origin.
Hipparchus (about 140 B.C.) and Ptolemy about three centuries later studied not only plane but also spherical trigonometry. They knew some of our formulas including sin2a + cos2a = 1, although of course, not using the same symbols, notations and representations.
The trigonometry which is being used now dates from the seventeenth century, stemming immediately after the Rebirth or Renaissance Period, when it was greatly improved particularly in relation to the symbols in Italy, Germany, England, and adjacent countries.
Etymologically speaking, trigonometry comes from the Greek words:
“tri” meaning “three”
“gonia” meaning “angle”
“metron” meaning “a measure”
Therefore, Trigonometry is the measurement of three angles or triangles.
TRIGONOMETRY involves functions of angles in a triangle, called trigonometric functions, which depend on ratios of the sides of the triangle. Trigonometry is widely utilized in the physical sciences, particularly in navigation, astronomy, surveying and mechanics. Without climbing a mountain top, its altitude can be measured through trigonometry. Without crossing a river, its breadth can be obtained through trigonometry. Trigonometric functions are also in other fields, such as analysis of financial markets, probability theory, statistics, biology, medical imaging, computer graphics and crystallography.
From six equilateral triangles, what polygon can be formed such that one of its side is equal to that of the triangle?
Now, learn how to use the hexagon in remembering trigonometric identities...and prove these identities. |
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