of less than rockwell 45c. materials do not have to be perfectly flat or smoothmachined ; in fact, only highly reflective materials ( such as polished stainless steel ) are problematic. marks can also be incorporated easily with most casting, forging or injection molding processes. in all cases, the mark becomes a design feature of the part. bbc marking withstands annealing, heat treating, and abrasive treatments, and is scannable after many coating processes as well. the service life of the mark equals that of the part itself. john deere introduced bumpy barcoding technology at its waterloo engine works. the company ' s first application for mecco ' s bumpy bar code technology was connecting rods. each connecting rod is split into two pieces during machining and must be reformed as a matched set. the system allows absolute verification that each rod and rod cap are a matched set. " now, if we would develop a problem with connecting rods, we could instantly identify the shift when it was produced, the individual machine involved, the specific quality measurement data generated, and the operator who was on duty, " says mr. schellhorn. " we can respond quickly and appropriately to any problem, but more importantly, we can respond proactively as well. the mecco system purchased by john deere includes a mecco sp202 computer controlled marking system and fixed base reader. to accommodate deere ' s requirement for a very fast cycle time, the system was engineered with three stations : two marking heads, and one fixed scanner, which was manufactured by sensis corp. the first station provides human - readable marking, the second indents the bbc marking ; the third station scans and verifies the integrity of the marks. fixturing, which was designed jointly by mr. schellhorn and mecco engineering vice president jim speicher, includes automated parts handling. the bbc is created by a chisel stylus that strikes the material surface and creates a bar about 1 / 8 inch in length. the reader is unique in that it reads both bumpy bar codes and traditional black and white printed bar codes, an advantage for users of both technologies. the reader is also distinctive in its use of a proprietary error detection algorithm, which makes misreading a virtual mathematical impossibility. bbc readers integrate readily with pcs, plcs, robots and other factory data equipment. they also plug into portable data terminals, which transfer data into a computer by saving it in memory for subsequent downloading, or by transmission via


or its treatment influence language development, the researchers tested babies on their ability to tell languages apart. they recruited 85 6 - month - old babies, 21 of whom had moms with depression and 32 of whom had moms with depression who had been treated during pregnancy with sris. at 6 months and 10 months, the babies heard recordings of the english syllable " da " and the hindi syllable " da. " to a native english speaker, these sounds are virtually indistinguishable, but they are subtly different : hindi speakers make their " da " sound by touching the tongue to their top teeth, while english speakers make their " da " by touching the tongue to the roof of the mouth behind the teeth. in a second experiment, the same babies watched silent videos of people speaking either english or french. normally, babies can tell the languages apart by mouth movements only until about 8 months of age. in both cases, researchers determined if babies could tell the difference between the languages by playing one and then switching to the other. they then measured if the babies looked longer at the new sound or not. if they did, the researchers knew they could tell the difference. if they didn ' t, it was because the new stimulus seemed the same as the old, and thus didn ' t attract the babies ' attention. [ photos : how babies learn ] depression and development the results revealed that kids of healthy, non - medication - taking moms could generally tell the languages apart at 6 months of age, but lost the ability at 10 months of age, as expected. but babies of moms with depression responded differently. when moms had received sri treatment, the babies displayed unusual maturity in their discrimination patterns : they failed to discriminate between different languages at 6 months old. a second experiment that involved playing vowels and consonants for fetuses of 36 weeks gestation found that the early maturation began even then. in fetuses of moms taking sris, recognition of native consonants was advanced. ( researchers measured recognition by tracking each fetus ' s heart rate. ) likewise, babies of depressed moms showed changes from the norm. these babies seemed to have a longer - than - usual sensitive period of language development. they could still differentiate between different languages at 10 months of age. in other words, sri treatment seems to accelerate a baby ' s attention to their own language, while unmedicated depression seems to delay that attention. researchers don ' t yet know whether this effect has any real - world consequences for how babies learn to speak


you might have seen photographers framing photos with their hands before taking a snap. but with the new prototype shooter dubbed ubi - camera, you will be able to use your hands to frame the photo as well as shoot it at the same time. the miniature camera is currently under development at the institute of advanced media arts and sciences. according to the video, “ when you draw a picture or take a photo, you sometimes form a rectangle with your hands to decide the composition. with this camera, you can take a photo using the exact same motion. you attach this device to your index finger, and form a rectangle with your finger like this ( see above ). you take the photo by using the rectangle as the viewfinder …. when you push hard with your thumb, the shutter is pressed ”. the ubi - camera comes equipped with a range sensor, and it detects the distance between the camera and the photographer ’ s face, and determines the framing. “ when you take a photo with your face close to the camera, you get a wide - angle shot …. and if you move it further away, you can take a close up shot ”. its lens has a fixed focal length, and you will be able to zoom in on something on your pc. although you won ’ t get that great feeling of holding a real camera when you are using the ubi - camera ( will also look a bit silly ), there is no need for viewfinders and displays for the new system. so we are expecting it to arrive with a low price tag. but the system is still in the development stage and needs much work to be done on it. “ here, the camera has a wired connection to a pc, but we ’ d like to make a stand - alone camera that can be freely used outside. also, the range sensor currently uses infrared, so it sometimes doesn ’ t detect your face properly, or it can be affected by light from the surroundings. so we ’ d like to use the camera to measure the distance as well, through face recognition. that would enable the system to be used more precisely ”.


radiosurgery, also called stereotactic radiosurgery, is a very precise form of therapeutic radiology. even though it is called surgery, radiosurgery does not involve actual surgery. rather, very focused beams of radiation ( gamma rays, x - rays, or protons ) are used to treat cancerous tissues without a surgical incision or opening. radiosurgery is called " surgery " because it is a one - session radiation therapy treatment that creates a similar result as an actual surgical procedure. radiosurgery works in the same manner as other types of therapeutic radiology : it distorts or destroys the dna of tumor cells, causing them to be unable to reproduce and grow. the tumor will shrink in size over time. for blood vessel lesions such as an arteriovenous malformation ( avm ), the blood vessels eventually close off after treatment. there are three types of radiosurgery. each type uses different equipment and radiation sources. radiosurgery types include : click image to enlarge - cobalt60 systems ( gamma knife ). cobalt60 systems use cobalt as a source for gamma rays. this type of system is commonly referred to as the gamma knife. the gamma knife is not really a knife at all. it uses beams of highly - focused gamma rays to treat small - to medium - size lesions, usually in the brain. many beams of gamma radiation join to focus on the lesion under treatment, providing a very intense dose of radiation in a safe manner. the gamma knife is used primarily to treat small and medium lesions in and around the brain, such as brain tumors, arteriovenous malformations ( abnormal connections between arteries and veins ), as well as functional problems such as trigeminal neuralgia. during gamma knife treatment, the equipment remains stationary ( does not move ). gamma knife treatment generally involves these steps : - head frame placement. in order to keep the head from moving during treatment, a box - shaped frame is attached to the head. pins designed specifically for this purpose fasten the head frame to the skull. the head frame also is a guide to focus the gamma ray beams to the exact location of the lesion being treated. - tumor location imaging. once the head frame is in place, the exact location of the lesion to be treated will be determined using computed tomography ( ct scan ) or magnetic resonance imaging ( mri ). - radiation dose planning. after the ct or mri scan has been completed, the radiation therapy team will determine the treatment plan.


the lesion to be treated will be determined using computed tomography ( ct scan ) or magnetic resonance imaging ( mri ). - radiation dose planning. after the ct or mri scan has been completed, the radiation therapy team will determine the treatment plan. the results of the imaging scan, along with other information, will be used by a medical physicist to determine the best treatment. - radiation treatment. after being positioned for the treatment, a type of helmet with many hundreds of holes in it is placed over the head frame. these holes help to focus the radiation beams on the target. treatment will last a few minutes up to a few hours, depending on the type and location of the area being treated. generally, only one treatment session is required for a lesion. - linear accelerator ( linac ) systems. linear accelerator ( linac ) systems use high - energy x - rays to treat large tumors or other lesions outside of the brain. some common types of linac systems include cyberknife, x - knife, novalis, and peacock. in addition to not using radioactive material to produce the radiation, linac systems also differ from the gamma knife in that the machinery moves around the patient during treatment. for this reason, linac systems are able to treat larger tumors and larger affected areas than the gamma knife. areas other than the brain can be treated with a linac system. linear accelerator systems may also be used for external beam radiation therapy. treatment steps with a linac system are generally the same or similar to the treatment steps used for the gamma knife. - proton beam therapy. proton beam therapy is a type of particle beam radiation therapy. rather than using rays of radiation, such as gamma rays or x - rays, particle beam therapy uses particles such as protons or neutrons. proton beam therapy is the most widely - used type of particle beam therapy. proton beam therapy is useful in treating tumors or lesions that are small and / or have an irregular shape. the radiation dose can be more closely controlled with these systems, because the proton beam can be controlled to allow it to deposit its energy almost completely in the tumor or lesion being treated. other forms of radiation lose energy as they enter body tissues on their way to the tissue under treatment. because the depth of the proton beam can be controlled so precisely, less damage occurs to normal tissues surrounding the area under treatment. proton beam therapy may be used for radiosurgery procedures or for fractionated radiotherapy ( several smaller doses of radiation over a certain period of time ). there are


wearing this watch in 1978 on board of the soyuz - 31 mission. it was the first analogue quartz wrist - watch generation from the ruhla factory and was very similar to the ruhla cal. 24 mechanical. this is presumably the only watch besides the nii electric that was specifically designed for spaceflight and actually used for that purpose. history of creation : story by vladimir а. dzhanibekov, twice the hero of soviet union, pilot - cosmonaut of ussr : september of 1985. " salute e 7 " station. it is midnight in moscow. it is also our local time. maintenance work going on... ice age. the flood at the station has already pasted. victor savinyh is cozily sleeping in a sleeping - bag in front of me. the " deaf " circuits without communication with center are going. - i wonder where we are flying? - i ' m asking almost in sleep, - above clouds i assume... falling asleep i idly thinking that it would be great to have a watch with globe like the one at on the central stand. or, with a map on the dial. but to have it on my hand... and without need to leave the warm sleeping bag to check... and soon getting back in again thinking that i was right and we were actually over clouds and under clouds were waters of the atlantic ocean... all right,.. water is there where clouds are. why our planet called the earth and not the water?.. this was the way the idea of " cosmonavigator " was born that salyut - 7 rescue was a classic bit of flying by dzhanibekov. he had to dock the spacecraft to a tumbling station with no beacon, just a laser rangefinder, sharp eyes and november 2004 yuri shargin has tested his private shturmanskie based on a poljot 31681 movement ( complication variant of the famous 3133 ) in space expedition. gallery of space related watches unknown watch used during a spacewalk for all the writing and the


macgregor campbell, consultant here ' s a freaky twist on a classic illusion. thomas papathomas, a vision researcher at rutgers university in new brunswick, new jersey, has created a new variation on the hollow - mask illusion - where viewers find it difficult to distinguish whether they are seeing a mask ' s interior or its exterior. papathomas ' s version uses both a hollow mask and a hollow torso, each inverted from the other so that when the head is concave, the torso is convex, and vice - versa. as the torso and head rotate, in the same direction, they appear to rotate oppositely to one another, resulting in the head appearing to twist unnaturally. papathomas calls this the " exorcist illusion, " referring to a famous scene in the 1973 horror movie, the exorcist, in which a girl possessed by the devil twists her head around a full 360 degrees. this illusion requires no satanic involvement however. a constantly rotating hollow mask - or torso - appears to rotate in one direction when the exterior is facing the viewer, and the opposite direction when the interior faces the viewer. since the brain and the torso are inverted from one another, when one appears to rotate clockwise, the other seems to rotate anticlockwise. papathomas created this illusion for the neural correlate society ' s 2012 illusion of the year contest.


the nobel prize in chemistry 1969 derek barton, odd hassel derek harold richard barton was born on 8 september 1918, son of william thomas and maude henrietta barton. in 1938 he entered imperial college, university of london, where he obtained his b. sc. hons. ( 1st class ) in 1940 and ph. d. ( organic chemistry ) in 1942. from 1942 to 1944 he was a research chemist on a government project, from1944 - 1945 he was with messrs. albright and wilson, birmingham. in 1945 he became assistant lecturer in the department of chemistry of imperial college, from 1946 - 1949 he was i. c. i. research fellow. in 1949 he obtained his d. sc. from the same university. during 1949 - 1950 he was visiting lecturer in the chemistry of natural products, at the department of chemistry, harvard university ( u. s. a. ). in 1950 he was appointed reader in organic chemistry and in 1953 professor at college. in 1955 he became regius professor of chemistry at the university of glasgow, in 1957 he was appointed professor of organic chemistry at imperial college, which position he still in 1950, in a brief paper in experientia entitled " the conformation of the steroid nucleus ", professor barton showed that organic molecules in general and steroid molecules in particular could be assigned a preferred conformation based upon results accumulated by chemical physicists, in particular by odd hassel. having chosen a preferred conformation, it was demonstrated that the chemical and physical properties of a molecule could be interpreted in terms of that preferred conformation. in molecules containing fixed rings, such as the steroids, there resulted a simple relationship between configuration and conformation, such that configurations could be predicted once the possible conformations for the products of a reaction could be analysed. thus the subject " conformational analysis " had begun. barton later determined the geometry of many other natural product molecules using this method. conformational analysis is useful in the elucidation of configuration, in the planning of organic synthesis, and in the analysis of reaction mechanisms. it will be fundamental to a complete understanding of enzymatic processes. prof. barton was invited to deliver the following special lectures : 1956, max tischler lecturer at harvard university ; 1958, first simonsen memorial lecturer of the chemical society ; 1961, falk - plaut lecturer, columbia university ; 1962, aub lecturer at harvard medical school ; renaud lecturer at michigan state university ; inaugural 3 m ' s lecturer, university of


ridgewood high school teacher lauded by nj inventors hall of fame a few years ago, using blackberry juice and titanium dioxide, a non - toxic ingredient found in powdered sugar, ridgewood " high school ( rhs ) science teacher lillian labowsky and her students began making dye - sensitized nanocrystalline solar cells with enough " juice " to power a calculator. three years after labowsky began the project, which was funded through a national science foundation ( nsf ) program that paired graduate students and grade school teachers to promote science education, it is clear labowsky did not just help her students make power - she also empowered them to invent. for her involvement in the innovative two - year project, labowsky has received accolades from both the state and the " district. the physics and chemistry teacher was recently recognized by the board of education ( boe ) for the 2012 " advancement of invention " award she received from the new jersey inventors hall of fame ( njihof ) in " october. she was one of only 25 scientists in the state, including three nobel prize laureates, to be inducted in the hall of fame. labowsky was nominated for the award by a stevens institute of technology graduate who helped her with the nsf program project. she was chosen because, according to the njihof, her teaching is " inspiring the next generation of scientists. " in a press release, her passion for science was deemed of " special note " and called " inspiring " by njihof president les avery. it was a high honor worthy of a teacher whose students, when contacted, spoke of her obvious passion and enthusiasm. it was also not the first time nobel prize winners have been closely associated with labowsky, who said she was inspired to teach by her yale university thesis adviser john fenn, winner of the 2002 nobel prize in chemistry. " it is my goal to try to inspire young scientists just as [ professor ] fenn inspired me, " said labowsky, who attended fenn ' s nobel prize ceremony. while labowsky is no longer participating in the nsf program because of a two - year limitation, the solar cell project " is still going strong, " she said. it has been integrated into her curriculum and expanded into a larger nanotechnology project. " i hope this project will serve as an enriching real world connection for my students, " she said. " we will continue to make blackberry juice solar cells to run small electronics as we


last modified : april 18, 2002 this information was provided by an unrestricted educational grant from integral pet associates, llc. clinically, a pet scan can locate metabolic defects in the human body often before they have caused structural damage. it can do this with high sensitivity and reliability. this is a great advantage in deciding treatment courses and in diagnosing various conditions. since pet accurately and sensitively measures function or physiology in the human body it can detect problems before they cause irreversible damage to tissues. it may also detect response to treatment earlier than many other techniques, such as ct or mri scans. the areas in which pet is making critical contributions are cancer, heart disease, and neurology. pet can detect active tumors in the body with very high sensitivity. active tumors have a high metabolism and therefore high demand for glucose. in this way malignant tumors may be distinguished from benign tumors and hidden tumors may be found. also the response of tumors to treatment ( surgery, chemotherapy, radiotherapy, immunotherapy or gene - therapy ) may be seen and measured earlier by pet than many other techniques. successfully treated tumors are destroyed physiologically often long before there is significant shrinkage of tumor volume. in this way stressful treatments can be assessed and completed earlier than might otherwise be possible. blood flow and glucose metabolism in the muscles of the heart may be accurately measured by pet. these measurements are made by imaging the distribution of intravenously injected radiolabeled ammonia ( blood flow ) and glucose ( metabolism ). areas of low blood flow but normal metabolism in the heart muscle indicate heart muscle that may be repaired by restoring blood flow ( repairing the appropriate coronary artery ), while areas of matched low blood flow and metabolism may already be irreversibly damaged and so require other treatments. in addition blood flow in the heart may be measured at rest and after exercise to detect partly obstructed arteries in the heart responsible for angina. seizures or epilepsy often start from a single focus of abnormal tissue in the brain. when the frequency and intensity of seizures do not respond well to medication, surgery may provide permanent relief. in any event, injection of a tiny amount of radiolabeled glucose is used to image the metabolism of the brain by pet. if you were to have a seizure around the time of glucose injection the seizure focus would be an area of intense metabolism ( and uptake ). between seizures the focus shows up as an area of decreased metabolism in the brain. brain trauma often results in subtle changes in


the missing key to physics, esp, intelligence, aging... as you know the discoveries of nikola tesla have been purposefully minimized in the media, college curriculums, and in the history books. well, there was another absolutely brilliant scientist whose discoveries are on a par with tesla ' s, but his work was very diligently minimized before it ever received widespread attention, and that scientist ' s name was albert roy davis. it may seem presumptuous to compare any scientist to tesla, but if there is one that you can compare to him, in my opinion, it ' s albert roy davis. in 1936 davis discovered that the north and south poles of magnetism are two separate energies with exact opposite effects on all matter. the north pole energy spins counterclockwise and causes matter to contract, and the south pole energy spins clockwise and causes matter to expand. davis and his associate, walter c. rawls, jr., found that this discovery had incredible implications in many areas of research. it is the key to understanding the " new physics ", the physics of ufo ' s. modern physics considers the two poles to be a singular form of energy, not two separate energies. magnetism is the foundation of physics. if you ' ve ever heard richard c. hoagland talk about the " russian physics ", let me tell you this : the russians knew nothing of this " new physics " until they adopted davis ' discovery. it is the key to tapping into the true potential of the human mind. davis and rawls discovered that north pole magnetism can be used to dramatically increase our intelligence and our psychic abilities. it is the key to understanding the legends of giants in ancient history, and the 2 - 3 foot beings as well. davis and rawls discovered that north pole exposed animals grew into much smaller, physically weaker adults. south pole exposed animals grew into much larger, physically stronger adults. it is the key to aging. davis and rawls discovered that both north pole and south pole exposed animals lived much longer than animals with no magnetic exposure.


reference sedation for this procedure. sperm collection. sperm are collected by means of masturbation or by taking sperm from a reference testicle opens new window through a small incision. this procedure is done when a blockage prevents sperm from being ejaculated or when there is a problem with sperm development. sperm may have been collected and frozen at an earlier time. then the sperm are thawed on the day the eggs are collected. fertilization and embryo transfer. the eggs and sperm are placed in a glass dish and incubated with careful temperature, atmospheric, and infection control for 48 to 120 hours. about 2 to 5 days after fertilization, the best fertilized eggs are selected. one to three are placed in the uterus using a thin flexible tube ( catheter ) that is inserted through the cervix. those remaining may be frozen ( cryopreserved ) for future attempts. pregnancy and birth. any reference embryos opens new window that implant in the uterus may then result in pregnancy and birth of one or more infants. what to expect after treatment overall, in vitro fertilization ( ivf ) - related injections, monitoring, and procedures are emotionally and physically demanding of the female partner. superovulation with hormones requires regular blood tests, daily injections ( some of which are quite painful ), frequent monitoring by your doctor, and harvesting of eggs. these procedures are done on an outpatient basis and require only a short recovery time. you may have cramping during the procedure. you may be advised to avoid strenuous activities for the remainder of the day or to be on bed rest for a few days, depending on your condition and your doctor ' s recommendation. why it is done in vitro fertilization may be a treatment option if : - a woman ' s reference fallopian tubes opens new window are missing or blocked. - a woman has severe reference endometriosis opens new window. - a man has low sperm counts. - reference artificial or intrauterine insemination opens new window has not been successful. - unexplained infertility has continued for a long time. how long a couple chooses to wait is influenced by the female partner ' s age and other personal factors. - a couple wants to test for inherited disorders before embryos are transferred. ivf can be done even if a : - woman has had a reference tubal ligation opens new window reversal surgery that was not successful. - woman does not have fall


as one - year olds play, they start to recognize patterns and understand shapes. they begin to sort familiar objects by one characteristic, such as whether they are " hard " or " soft. " they may enjoy filling and emptying containers. they notice that night is followed by day, and that socks go on feet before shoes. they know that when an object is hidden, it is still there. many can also do simple insert puzzles when the puzzle pieces show whole objects. between 18 - 24 months, some children will begin to use a few number words without understanding quantity ( e. g., imitates a simple counting rhyme ). some children may also begin to understand the words " one " and " two " ( e. g., distinguishes " one " or " two " from many ; identifies pairs of items as " two ; " identifies three or more items as " many " rather than as " one " or " two ; " asks for " one " or " two " of something ; knows age ; responds appropriately to the request, " take just one, " or " give me two. " ). between 18 - 24 months, a few children will begin to nonverbally and mentally determine that one item added to another makes " two, " and that one item taken away or subtracted from " two " makes " one. " between 12 and 18 months, the average child understands that when an object is completely hidden, it is still there ( " object permanence " ), and can be recovered. ( some children may understand this between 18 - 24 months. ) during the first half of this year, some children will even be able to recover an object that has been hidden in one place, and then visibly moved to a second position and re - hidden. ( the average child will establish such " object permanence " during the second half of this year. ) during the first half of this year, the average child will also be able to recover an object that has been covered with one item, and then covered with something else while remaining in the same position between 18 and 24 months, some children will informally identify and play with solid objects ( e. g., picks out a familiar object by touch when that object is placed in a bag with two other objects ). between 12 - 24 months, children are typically able to work simple " insert " puzzles ( e. g., completes a three - piece simple puzzle where pieces are whole objects ). also, children can remove a part from


two other objects ). between 12 - 24 months, children are typically able to work simple " insert " puzzles ( e. g., completes a three - piece simple puzzle where pieces are whole objects ). also, children can remove a part from a toy ( e. g., a wheel ) and replace it. finally, children can build three - dimensional structures using one type of item ( e. g., a cube ). between 12 - 18 months, children adjust their reach based on the distance and size of an object ( e. g., accurately reaches and closes hand around an item instead of missing the object or closing hand before contact ). children also adjust their grasp of an object based on its weight ( i. e., no longer grasps all items tightly or allows arm to drop when given heavy items ). some children at 12 - 18 months believe that a cracker broken into many pieces is more food than the same type of cracker that is whole. ( the average child believes this between 18 - 24 months. ) some children during the second half of this year will explore objects by filling and emptying containers ( e. g., with sand or water ). during the second half of this year, a few children begin to develop a sense of time through participation in routine daily activities ( e. g., knows about when it is time to eat, nap time, etc. ). children ' s sense of time develops gradually over the next several years. between 12 - 18 months, some children recognize that there is an order to the day ( e. g., mommy comes to get me after storytime ). the average child sees daily patterns by the second half of this year. in the second half of the year, some children show a greater understanding of daily time sequence ( e. g., time to eat, nap time, etc. ). during the second half of the year, some children notice patterns in the environment ( e. g., day follows night, patterns in carpeting or clothing, etc. ). they also use the terms, " tomorrow, " and " yesterday. " in the second half of this year, some children show interest in patterns or sequence ( e. g., attempts to follow patterns with stringing beads, magnetic shapes, peg boards ). between 18 - 24 months, some children can classify, label and sort familiar objects by a known group ( e. g., hard v. soft, large v. small, heavy v


solar electrical power is the particular conversion of sunshine into electricity, either straight making use of photovoltaics ( pv ), and / or indirectly utilizing concentrated solar electric power ( csp ). commercial concentrated solar force vegetation were 1st developed within the 1980s. the actual 354 mw segs csp installing the components is actually the biggest solar electrical power plant throughout the globe, placed within the mojave desert of california. some other big csp plants include the actual solnova solar power station ( 150 mw ) plus the andasol solar electric power station ( 150 mw ), both throughout spain. the actual 214 mw gujarat solar park inside india, is actually the entire globe s biggest photovoltaic plant. solar force typically is the conversion of sunshine into electricity. sunshine is converted straight into electricity applying photovoltaics ( pv ), or simply indirectly with concentrated solar force ( csp ), that normally concentrates the actual sun ' s stamina that would boil water that is afterward used to provide energy. other technologies furthermore exist, for instance stirling engine dishes which incorporate a stirling cycle motor to electrical power a generator. photovoltaics were initially chosen to power little and also medium - sized applications, from the calculator driven by a single solar mobile that would off - grid homes driven by a photovoltaic range. a parabolic trough consists of the linear parabolic reflector which concentrates light onto a receiver placed over the reflector ' s focal line. the recipient is a tube positioned right above the entire center associated with the parabolic mirror and also is actually filled with a functioning liquid. the particular reflector is actually built to follow the actual sun during the entire daylight hours by tracking along a single axis. parabolic trough systems provide the ideal land - use factor of any solar development. the actual segs vegetation within california not to mention acciona ' s nevada solar one near boulder city, nevada are generally representatives of this development. compact linear fresnel reflectors happen to be csp - plants which employ countless thin mirror strips instead of parabolic mirrors to be able to focus sunshine onto two tubes alongside working liquid. this particular has the advantage which flat mirrors will likely be chosen that are much cheaper compared to parabolic mirrors, and additionally that more reflectors will be put within the exact same amount of space, permitting more of the available sunshine in order to be chosen. focusing linear fresnel reflectors can certainly be utilized in either big or even more compact plants. for more information, check out : pre


when we exercise, our heart rates increase, and when we sleep, they drop. but sometimes, when we ' re working during the day and minding our business, our heart skips a beat. during any 24 - hour period, in fact, one - fifth of adults may experience this phenomenon and not know it. when extra beats happen in quick succession, the heart can enter a chaotic state, leading to a condition known as arrhythmia, which is treated with daily medication or, in more severe cases, electrical pulses that return the heart to normalcy. teresa chay is a biophysicist who suffers from arrhythmia. she developed the condition as a child after rheumatic fever damaged two heart valves. surgery seven years ago replaced the valves, but she still takes daily medication and occasionally needs to rush to the hospital for electrical pulse treatment. since her surgery, chay has studied arrhythmia. using supercomputers at the pittsburgh supercomputing center, she has developed a mathematical model that explains why arrhythmia begins and why it stops when electric shocks are applied. her goal, like other researchers in this field, is providing a foundation for developing better drugs to control arrhythmia. currently, the drugs are not always effective, and in some cases, for reasons not well understood, rather than controlling arrhythmia they can trigger it and kill you. researcher : teresa chay, university of pittsburgh. hardware : cray c90 software : user developed code keywords : arrhythmia, heart, heart rate, electrical pulse treatment, anti - arrhythmic drugs, ion channels, sudden cardiac death, atrial fibrillation, erratic beating, chaotic state, nonlinear dynamics, chaos theory, bifurcation analysis, coexistence theory, reentrant arrhythmia, self beating, quiescent state, sinus node. related material on the web : more information about dr. chay and her research, from the community of science web server. projects in scientific computing, psc ' s annual research report. references, acknowledgements & credits


final results ( phase 1, 2 and 2b ) the data that is gathered constitutes an important collection of information on the currents that form within the system and between the system and the surrounding areas, and on the chemical and physical characteristics of the column of water. this knowledge provides a reference framework for the interpretation of analytical data regarding the movement of masses of water and the transport of matter and polluting substances inside the network of canals. the expansion of the system under observation has also made it possible to validate the two - dimensional model of the finite elements for the lagoon – available to insula – that simulates the propagation of a wave from the inlets at the outer margins of the city ( technical report “ d2 ” ) and that provides the surrounding conditions for the two - dimensional link - node model of the inner canals. with the uninterrupted acquisition of time - based series of chemical and physical parameters, the periodicity of some processes was also investigated. in particular, the series of turbidity values made it possible to assess the phenomenon of the re - suspension of sediment from the bottom of the canals over a more extended span of time. the study highlighted how the primary factor in determining the turbidity of the waters inside the system is the circulation of motor boats and depends on the intensity of the traffic, of the water head and the tide conditions. an estimate of the flow of sedimentation made by placing five traps across a more extended area has made it possible to compare different canal systems. the data relative to the entire monitoring period highlights a distinct differentiation of the flow of sediment, in relation to the different hydrodynamic conditions in the five canals under observation. however, the evolution over time of the flow in the different sites is similar, with relatively low values in winter, followed by a progressive increase in the flow in the springtime. the results confirm the strict relationship between the hydrodynamic characteristics of each single canal, the quality of the material that collects on the bottom, and the intensity of the metabolic processes. as seen in a preliminary manner during phase 1, the sedimentation traps, jointly with the constant measuring of the turbidity, are an effective system for studying the variations in the phenomena of sediment re - suspension and transport within the network of canals in the historic city centre of venice. the investigation makes it possible to explore the mechanisms of sedimentation, an aspect that is particularly interesting to insula : the objective is to predict the rate of sedimentation of the materials in the canals,


of canals in the historic city centre of venice. the investigation makes it possible to explore the mechanisms of sedimentation, an aspect that is particularly interesting to insula : the objective is to predict the rate of sedimentation of the materials in the canals, and hence to program dredging operations. the results of the analyses on the water samples taken during the measuring campaigns, confirm the importance of determining the concentration of suspended particles for the evaluation of the transport of solids and heavy metals in the canals of venice. the dissolved species of nitrogen and phosphorus, in particular ammonia and orthophosphate, constitute a very precise tracer of the qualitative variations of a column of water, that are introduced as a result of the draining of waste water, or the route of the water and the length of time they stay in the system. these results further highlight the fundamental role of circulation in establishing the behaviour of contaminants from the urban waste inside the system. at the close of phase 2, on the basis of the results acquired during the study, a methodological protocol ( or specification ) was drafted, describing appropriate monitoring methodologies for assessing possible variations, over a relatively short span of time, in the quality of the water in the canal networks of the historic city centre ( icaro project, phases 1 and 2 – results and methodologies, january 2004 ).


| rediff india abroad home | all the sections | what is 3g spectrum? how does it help you? rediff business desk | september 29, 2006 it ' s boom time for mobile phones in india. and people are looking forward to more information, faster data access and multimedia services through their mobile phones. 3g technology is here to turn this dream into reality. it ' s a technology anxiously awaited by telecom operations and subscribers in india. how long do you have to wait? not very long! india is all set to launch 3g mobile telephone services by june 2007. according to telecom regulatory authority of india chairman nripendra misra, a total of 32. 5 mhz is available for allocation within the next 6 - 9 months. trai has also recommended auctioning 200 mhz for broadband wireless access services like wimax ( worldwide interoperability for microwave access ) and has proposed a national frequency management board to oversee spectrum availability and its efficient use. he hopes that the allocated spectrum would be enough for the next two years and said trai would recommend freeing up more spectrum for those who lose out in this auction. so what is 3g spectrum all about? read on. what is spectrum? radio spectrum refers to a range of radio frequencies. the bandwidth of a radio signal is the difference between the upper and lower frequencies of the signal. for example, in the case of a voice signal having a minimum frequency of 200 hertz ( hz ) and a maximum frequency of 3, 000 hz, the bandwidth is 2, 800 hz ( 3 khz ). the amount of bandwidth needed for 3g services could be as much as 15 - 20 mhz, whereas for 2g services a bandwidth of 30 - 200 khz is used. hence, for 3g huge bandwidth is required. how is 3g different from 2g and 4g? while 2g stands for second - generation wireless telephone technology, 1g networks used are analog, 2g networks are digital and 3g ( third - generation ) technology is used to enhance mobile phone standards. 3g helps to simultaneously transfer both voice data ( a telephone call ) and non - voice data ( such as downloading information, exchanging e - mail, and instant messaging. the highlight of 3g is video telephony. 4g technology stands to be the future standard of wireless devices. currently, japanese company ntt docomo and samsung are testing 4g communication. how will 3g services help you? 3g services will enable video broadcast and data - intensive services such as stock transactions, e


s the physician, now published in many languages. moreover, according to ibn al - nadim, al - farabi, a well - known philosopher and scientist, was from the faryab province of afghanistan. before the taliban gained power, the city of kabul was home to many musicians who were masters of both traditional and modern afghan music, especially during the nauroz - celebration. kabul in the middle part of the twentieth century has been likened to vienna during the eighteenth and nineteenth centuries. the tribal system, which orders the life of most people outside metropolitan areas, is potent in political terms. men feel a fierce loyalty to their own tribe, such that, if called upon, they would assemble in arms under the tribal chiefs and local clan leaders ( khans ). in theory, under islamic law, every believer has an obligation to bear arms at the ruler ' s call ( ulul - amr ). heathcote considers the tribal system to be the best way of organizing large groups of people in a country that is geographically difficult, and in a society that, from a materialistic point of view, has an uncomplicated lifestyle. religiously, afghans are over 99 % muslims : approximately 74 - 80 % sunni and 19 - 25 % shi ' a ( estimates vary ). up until the mid - 1980s, there were about 30, 000 to 150, 000 hindus and sikhs living in different cities, mostly in jalalabad, kabul, and kandahar. the economically active population in 2002 was about 11 million ( out of a total of an estimated 29 million ). as of 2005, the official unemployment rate is at 40 %. the number of non - skilled young people is estimated at 3 million, which is likely to increase by some 300, 000 per annum. the nation ' s economy began to improve since 2002 due to the infusion of multi - billion us dollars in international assistance and investments, as well as remittances from expats. it is also due to dramatic improvements in agricultural production and the end of a four - year drought in most of the country. the real value of non - drug gdp increased by 29 % in 2002, 16 % in 2003, 8 % in 2004 and 14 % in 2005. as much as one - third of afghanistan ' s gdp comes from growing poppy and illicit drugs including opium and its two derivatives, morphine and heroin, as well as hashish production. opium production in afghanistan has soared to a new record in 2007, with an increase on last year of


photonics : sensing on the way published online 01 august 2012 hollow optical fibers containing light - emitting liquids hold big promises for biological sensing applications schematic illustration of a hollow fiber. the chemiluminescent liquid in the core ( yellow ) is guided through the fiber, also with help of further hole structures ( dark blue ). processing biological samples on a small substrate the size of a computer chip is becoming a common task for biotechnology applications. given the small working area, however, probing samples on the substrate with light can be difficult. to address this issue, xia yu and co - workers at the a * star singapore institute of manufacturing technology have now developed an optical fiber system that is able to deliver light to microfluidic chips with high efficiency1. “ our compact optical fibers are designed for use with high - throughput detection systems, ” says yu. “ they are ideal for use in space - restrictive locations. ” a common way of probing biological samples is by light. in this method, the sample is excited by an external light source and the light emitted in response is detected, which provides a unique fingerprint of the substance. conventional techniques are able to deliver light to samples and probe the response, but they are not very efficient at probing a small sample volume. a solution to this is to use optical fibers that are able to guide light to small spaces. the drawback with this technique, however, has been that it can be difficult to insert the external probe light into the optical fiber with sufficient efficiencies. yu and her co - workers have now circumvented this problem by using optical fibers with a hollow core ( see image ). the empty hollow core can be filled with liquids — in this case, with chemiluminescent solutions. the liquid is important to promote the transport of light through the core. in addition, these solutions consist of two liquids that when brought together initiate a chemical reaction that emits light. if such a solution is placed directly within the hollow core the problem of coupling light into the fiber is circumvented. this not only avoids external light sources but also promotes an established technology. “ the use of chemical luminescence is a common technique for a variety of detection assays in biology, ” says yu. “ by incorporating the emission mechanism into optical fibers, we can use it as a light source for sensing applications in microfluidics systems. ” first tests for such sensing applications are already underway, although some challenges remain. for example, there


career : propagation systems for generation of chromosomally stable human embryonic stem cells ( virginia commonwealth university ) raj rao and members of his research group at virginia commonwealth university have developed a new material free of animal components that produces stable, non - tumor - forming stem cells. traditionally, human stem cell growth systems involve the use of animal - derived components. these elements raise the risk of genetic mutations and the spread of disease in new cells. development of stable, non - tumor - forming, disease - free stem cells will advance stem cell therapies to treat human diseases. human stem cells have gained enormous interest as potential sources for regenerative biomedical therapies and model systems for studying early human development. however, the process is labor intensive and can result in nonuniform, unstable human stem cell cultures. in addition, traditional stem cell growth systems lead to a mixture of stem cells. some of these networks develop into normal tissues and cells, while others form cancers. stem cell cancers are typically some of the hardest to treat. rao ' s findings will enable investigators to use well - defined materials to manufacture stem cells that are disease free, stable and non - tumor forming. researchers re - create fish hair cell sensors and musclesresearch areas : engineering locations : virginia research could have a significant impact on bioengineered replacement materialsresearch areas : engineering locations : virginia


• select site currency select a currency for use throughout the site physical database design. the morgan kaufmann series in data management systems elsevier science and technology, june 2007, pages : 448 the rapidly increasing volume of information contained in relational databases places a strain on databases, performance, and maintainability : dbas are under greater pressure than ever to optimize database structure for system performance and administration. physical database design discusses the concept of how physical structures of databases affect performance, including specific examples, guidelines, and best and worst practices for a variety of dbmss and configurations. something as simple as improving the table index design has a profound impact on performance. every form of relational database, such as online transaction processing ( oltp ), enterprise resource management ( erp ), data mining ( dm ), or management resource planning ( mrp ), can be improved using the methods provided in the book. the first complete treatment on physical database design, written by the authors of the seminal, database modeling and design : logical design, 4th edition. includes an introduction to the major concepts of physical database design as well as detailed examples, using methodologies and tools most popular for relational databases today : oracle, db2 ( ibm ), and sql server ( microsoft ). focuses on physical database design for exploiting b + tree indexing, clustered indexes, multidimensional clustering ( mdc ), range partitioning, shared nothing partitioning, shared disk data placement, materialized views, bitmap indexes, automated design tools, and more! 1 introduction to physical database design 2 basic indexing methods 3 query optimization and plan selection 4 selecting indexes 5 selecting materialized views 6 shared - nothing partitioning 7 range partitioning 8 multidimensional clustering 9 the interdependence problem 10 counting and data sampling in physical design exploration 11 query execution plans and physical design 12 automated physical database design 13 down to the metal : server resources and topology 14 physical design for decision support, warehousing, and olap 16 distributed data allocation appendix a a simple performance model for databases appendix b technical comparison of db2 hadr with oracle data guard for database disaster recovery lightstone, sam s. sam lightstone is a senior technical staff member and development manager with ibm ' s db2 product development team. his work includes numerous topics in autonomic computing and relational database management systems. he is cofounder and leader of db2 ' s autonomic computing r & d effort. he is chair of the ieee data engineering work


product development team. his work includes numerous topics in autonomic computing and relational database management systems. he is cofounder and leader of db2 ' s autonomic computing r & d effort. he is chair of the ieee data engineering workgroup on self managing database systems and a member of the ieee computer society task force on autonomous and autonomic computing. in 2003 he was elected to the canadian technical excellence council, the canadian affiliate of the ibm academy of technology. he is an ibm master inventor with over 25 patents and patents pending ; he has published widely on autonomic computing for relational database systems. he has been with ibm since 1991. teorey, toby j. toby j. teorey is a professor in the electrical engineering and computer science department at the university of michigan, ann arbor. he received his b. s. and m. s. degrees in electrical engineering from the university of arizona, tucson, and a ph. d. in computer sciences from the university of wisconsin, madison. he was general chair of the 1981 acm sigmod conference and program chair for the 1991 entity - relationship conference. professor teorey ' s current research focuses on database design and data warehousing, olap, advanced database systems, and performance of computer networks. he is a member of the acm and the ieee computer society. tom nadeau is the founder of aladdin software ( aladdinsoftware. com ) and works in the area of data and text mining. he received his b. s. degree in computer science and m. s. and ph. d. degrees in electrical engineering and computer science from the university of michigan, ann arbor. his technical interests include data warehousing, olap, data mining and machine learning. he won the best paper award at the 2001 ibm cascon conference.


chemical technology news from across rsc publishing. nanofactories monitor bacteria communication 03 march 2010 scientists in the us have developed a microdevice that investigates how bacteria communicate with each other to enhance their resistance to drugs. bacteria communicate in a process called quorum sensing, in which they secrete small signalling molecules called autoinducers. when bacteria produce a quorum, their resistance to drugs is enhanced. william bentley and co - workers from the university of maryland have developed bio - inspired nanoscale factories that capture bacteria, deliver a drug right on the surface of the bacteria and test their responses. ' the overall goal is to understand how pathogens communicate with each other to make a more formidable team than each individual cell. we ' re trying to break down what exactly a quorum is and how it works ', explains bentley. microdevice could help develop the next generation of antimicrobials the nanofactories assemble themselves on a chitosan coated electrode within a microfluidic device. they contain multiple modules that each perform a different function, including targeting and capturing bacteria cells, sensing raw materials in the vicinity and converting the raw materials into autoinducer molecules and transporting these back to the bacteria cell surface. bentley used bacteria cells that were specially constructed to express a fluorescent protein in response to autoinducer signalling, which could be easily seen. the autoinducer molecules made by the nanofactories triggered the quorum sensing response of the bacteria, causing them to express the fluorescent protein. ' we ' re developing tools that enable rapid, cost - effective assembly of complex biological systems on devices so that the device can interrogate what the biology is doing ', bentley adds. michael shuler, an expert in bioengineering at cornell university, ithaca, us, called the concept of nanofactories ' highly intriguing and novel '. he said that while applying the technique to the capture of quorum sensing bacteria was important for controlling some types of bacteria without antibiotics, the most exciting thing for him was the potential of the nanofactories to be integrated with microfluidics or other nanotechnologies. in the future bentley hopes that increasingly complex biological systems could be assembled to recreate the environment that bacteria see. he hopes to use the method to study other systems including epithelial and cancer cells. enjoy this story? spread the word using the ' tools ' menu on the left or add a comment to the chemistry world blog. link to journal article biological nanofactories facilitate


filed under : computers often, when people talk about the future of user interaction with computers, the go - to reference is steven spielberg ’ s ‘ minority report. ’ but those dreams of gesture - based computing find users waving their hands in the air with no tactile feedback at all, and anyone who has typed on both an iphone and a blackberry can tell you a little physical feedback is always welcome. an experimental system being developed at gifu university in japan marries that sort of hand gesture - based experience with 3 - d displays and haptic feedback to create an experience that more closely resembles manipulating objects in the real world. the hiro iii requires that you strap your fingertips into a robot hand, which has fingers that simulate the texture of real surfaces to provide a sense of weight to your on - screen interactions. for example, if you ’ re running your hand across a jagged surface, the hiro iii will appropriately recreate that feeling. when combined with a 3 - d display, the experience should be quite immersive. the system has obvious applications for controlling robot arms, as well as for simulating surgical and diagnostic procedures for medical students. check out the video of hiro iii in action after the break. [ from : engadget ] continue reading in hiro iii, researchers see scientific breakthrough, we see feel - o - vision in hiro iii, researchers see scientific breakthrough, we see feel - o - vision originally appeared on switched on wed, 30 jun 2010 11 : 00 : 00 est. please see our terms for use of feeds. read | permalink | email this | comments


may 26, 2000 iowa city, iowa - - long - term exposure to radon in the home is associated with lung cancer risk and presents a significant environmental health hazard, according to a study led by researchers at the university of iowa college of public health. the iowa radon lung cancer study, funded by the national institute of environmental health sciences, included investigators from the ui, st. john ' s university in collegeville, minn. and the university of kansas. the results are published in the june 1 issue of the american journal of epidemiology. from 1993 to 1997, the researchers studied 1, 027 iowa women - - 413 who were newly diagnosed with lung cancer and 614 " controls " - - ages 40 to 84 who had lived in their homes for the past 20 years or more. the women studied in both groups included smokers as well as nonsmokers. women were studied because they typically have less occupational exposures to substances that may cause lung cancer, and historically have spent more time in the home. the researchers found that close to 60 percent of the basement radon concentrations for both the lung cancer cases ( study participants with lung cancer ) and the control group ( participants without lung cancer ) exceeded the u. s. environmental protection agency action level for radon of 4 picocuries per liter ( pci / l ). the researchers found that 33 percent of living areas for the lung cancer cases, and 28 percent of the living areas for the control group, exceeded the epa ' s action level of 4 pci / l. even at the epa action level of 4 pci / l, an approximate 50 percent excess lung cancer risk was found among the women in the study after correcting for the impact of smoking, according to charles lynch, ui professor of epidemiology and the study ' s principal investigator. " what this indicates is that residential radon exposure is a significant cause of lung cancer, " lynch said. at least four radon detection devices were placed in different areas in each of the study subjects ' homes for one year. the researchers linked these multiple home radon measurements, as well as estimates on radon exposure outside the subjects ' homes, with the subjects ' past mobility history - - where and how much time they had spent outside or inside their homes or in the workplace, for example. with this information, the researchers were able to determine actual detailed exposure estimates for each study participant. " this study incorporated the most sophisticated radon exposures analysis ever performed in a residential epide


june 4, 2005 autism therapy is bedeviled by unpredictable outcomes. even with the best behavioral treatments, which are the only ones to have been scientifically demonstrated to work - - says laura schreibman, professor of psychology and director of the autism research program at ucsd - - some children improve dramatically, some only somewhat and others not at all. many families try one thing after another, losing precious months before hitting on the therapeutic method best suited for their autistic child. given the importance of early intervention, schreibman said, " we need to get it right the first time. " a new study coauthored by schreibman and recent doctoral graduate michelle sherer successfully matches autistic children with an appropriate therapy. published in the june issue of the american psychological association ' s journal of consulting and clinical psychology, the study is the first to develop and test a predictive profile of children likely to respond to a particular treatment, in this case pivotal response training. prt is a child - directed behavioral intervention developed by schreibman and uc santa barbara colleague robert l. koegel. focused on improving a child ' s motivation and responsiveness, prt targets language skills, play skills and social behaviors that can be generalized to a natural, non - lab setting. the researchers began by examining data from 28 children who had participated in previous investigations of prt. characteristics of the poorest and most exceptional responders were used to develop the predictive profile. children expected to do well with prt were those who showed a moderate to high interest in toys, were tolerant of another person in close proximity, and, relative to those with poor outcomes, had fewer non - verbal stimulatory behaviors ( flapping or rocking, for example ) and more verbal self - stimulatory behaviors ( squeaking or other nonsensical sounds ). a prospective study followed : six new participants were selected - - three who were predicted to respond to prt and three who were not. each prospective responder was matched to a non - responder on iq, language age and symptom severity. two boys and girl, the responders ranged in chronological age from 3 years, 0 months to 3 years, 5 months. the non - responders were likewise two boys and a girl, aged chronologically from 3 years, 1 month to 5 years, 10 months. the children received 90 minutes of one - on - one prt four to five times a week by trained, advanced psychology students who were


likewise two boys and a girl, aged chronologically from 3 years, 1 month to 5 years, 10 months. the children received 90 minutes of one - on - one prt four to five times a week by trained, advanced psychology students who were blind to the hypothesis of the study. after five weeks, prt treatment was stopped for the non - responders because they failed to show any improvement, and it was ethically indefensible to continue. they were referred to other programs. ( the non - responders ' slightly higher chronological age did not appear to be a factor. in fact, the youngest child of this group was among the poorest performing. ) responders received a total of six months, or approximately 190 hours, of treatment. as predicted, they made significant gains on several measures. children " r1 " and " r2, " for example, began the study with no functional communication. by the second month, both were talking during and outside of treatment sessions. skeptics might charge that the profile developed by sherer and schreibman merely picks out children who will improve with any and all behavioral treatment. an important insight, however, the authors write, is provided by the non - responders who were discontinued from the study. " nr1, " for instance, who did not derive any benefit from prt, made great gains with another method - - suggesting the profile is specifically predictive for outcomes with prt. subsequent research led by schreibman is confirming this finding. " this is just a start in the right direction. it is one profile for one therapy, " said schreibman, author of autism and the forthcoming the science and fiction of autism ( harvard university press, nov. 2005 ). " we in the autism community know there is no one - size - fits - all approach. to reduce outcome variability, we need to continue finding predictor variables and to develop a full inventory of tailored treatments. " schreibman ' s lab is currently working on adapting its prt profile so that it can more easily be used in schools and other real - world environments. the authors urge further research to develop profiles for all other behavioral therapies. the study was supported by a grant from the national institute of mental health. other social bookmarking and sharing tools : note : materials may be edited for content and length. for further information, please contact the source cited above. note : if no author is given, the source is cited instead.


july 26, 2012 excitation of neurons depends on the selected influx of certain ions, namely sodium, calcium and potassium through specific channels. obviously, these channels were crucial for the evolution of nervous systems in animals. how such channels could have evolved their selectivity has been a puzzle until now. yehu moran and ulrich technau from the university of vienna together with scientists from tel aviv university and the woods hole oceanographic institution ( usa ) have now revealed that voltage - gated sodium channels, which are responsible for neuronal signaling in the nerves of animals, evolved twice in higher and lower animals. these results were published in cell reports. the opening and closing of ion channels enable flow of ions that constitute the electrical signaling in all nervous systems. every thought we have or every move we make is the result of the highly accurate opening and closing of numerous ion channels. whereas the channels of most lower animals and their unicellular relatives cannot discern between sodium and calcium ions, those of higher animals are highly specific for sodium, a characteristic that is important for fast and accurate signaling in complex nervous system. surprising results in sea anemones and jellyfish however, the researchers found that a group of basal animals with simple nerve nets including sea anemones and jellyfish also possess voltage - gated sodium channels, which differ from those found in higher animals, yet show the same selectivity for sodium. since cnidarians separated from the rest of the animals more than 600 million years ago, these findings suggest that the channels of both cnidarians and higher animals originated independently twice, from ancient non - selective channels which also transmit calcium. since many other processes of internal cell signaling are highly dependent on calcium ions, the use of non - selective ion channels in neurons would accidently trigger various signaling systems inside the cells and will cause damage. the evolution of selectivity for sodium ions is therefore considered as an important step in the evolution of nervous systems with fast transmission. this study shows that different parts of the channel changed in a convergent manner during the evolution of cnidarians and higher animals in order to perform the same task, namely to select for sodium ions. this demonstrates that important components for the functional nervous systems evolved twice in basal and higher animals, which suggests that more complex nervous systems that rely on such ion - selective channels could have also evolved twice independently. other social bookmarking and sharing tools : note : materials may be edited for content and length. for further information, please contact the source cited above. note : if no author is


lived long ago. fossils are often found in sedimentary rocks. paleontology the scientific study of life in the past, especially through the study of fossils. sauropod one of the two types of saurichian dinosaurs, widespread during the jurassic and cretaceous periods. sauropods were plant - eaters and often grew to tremendous size, having a stout body with thick legs, long slender necks with a small head, and long tails. sauropods included the apatosaurus ( brontosaurus ) and brachiosuarus. sedimentary rock a rock that is formed when sediment, such as sand or mud, becomes hard. sedimentary rocks form when sediments are collected in one place by the action of water, wind, glaciers, or other forces, and are then pressed together. limestone and shale are sedimentary rocks. stegosaurus or stegosaur any of several plant - eating dinosaurs of the jurassic and cretaceous periods. stegosaurus had a spiked tail and an arched back with a double row of large, triangular, upright, bony plates. although stegosaurs grew to 20 feet ( 6. 1 meters ) in length, they had tiny heads with brains the size of a walnut copyright © 2002, 2003 houghton - mifflin company. all rights reserved. used with permission. return to article behind the scenes hot sites & cool books


in a. d. 79 mount vesuvius erupted, annihilating the cities of pompeii and herculaneum and killing thousands who did not evacuate in time. to avert a similar fate for present - day naples, which lies six miles west of the still active vesuvius, as well as for the cities near volatile mount etna in sicily, a novel laser system could soon forecast volcanic eruptions up to months in advance. current methods to predict eruptions have downsides. seismometers can monitor tremors and other ground activity that signal a volcano ' s awakening, but their readings can prove imprecise or complicated to interpret. scanning for escaping gases can reveal whether magma is moving inside, but the instruments used to analyze such emissions are often too delicate and bulky for life outside a laboratory. " you have to collect samples from the volcano, bring them to a lab, and often wait through backlogs of weeks to months before analysis, " explains frank tittel, an applied physicist at rice university. a more promising technique for early detection focuses on changes in carbon isotopes in carbon dioxide. the ratio between carbon 12 and carbon 13 is roughly 90 to one in the atmosphere, but it can differ appreciably in volcanic gases. a ratio change by as little as 0. 1 part per million could signal an influx of carbon dioxide from magma either building under or rising up through the volcano. lasers can help detect this change : carbon 12 and 13 absorb light at slightly different mid - infrared wavelengths. the lasers must continuously tune across these wavelengths. previously investigators used lead - salt lasers, which require liquid - nitrogen cooling and thus are impractical in the field. furthermore, they are low - power devices, generating less than millionths of a watt, and can emit frequencies in an unstable manner. other isotope scanning techniques are similarly lab - bound. tittel and other scientists in the u. s. and britain, in partnership with the italian government, have devised a volcano - monitoring system around a quantum - cascade laser. such a semiconductor laser can produce high power across a wide frequency. moreover, they are rugged and do not require liquid - nitrogen cooling, making them compact enough to fit inside a shoe box. the researchers first tried out their device on gas emissions from nicaraguan craters in 2000. the new field tests will check its performance and accuracy in harsh volcanic locales. dirk richter, a research engineer at the national center for atmospheric research in boulder, colo., says it would prove


on gas emissions from nicaraguan craters in 2000. the new field tests will check its performance and accuracy in harsh volcanic locales. dirk richter, a research engineer at the national center for atmospheric research in boulder, colo., says it would prove difficult to design a system " to work in one of the worst and most challenging environments possible on earth, " but " if there ' s one group in the world that dares to do this, that ' s frank tittel ' s group. " if the instrument works, the plan is to deploy early - warning systems of lasers around volcanoes, with each device transmitting data in real time. false alarms should not occur, because carbon isotope ratios in magma differ significantly from those in the crust. the changes that the laser helps to detect also take place over weeks to months, providing time to compare data from other instruments, as well as ample evacuation notice. " our system aims at avoiding a catastrophe like the vesuvius eruption, " says team member damien weidmann, a physicist at the rutherford appleton laboratory in oxfordshire, england. field tests for the prototype are planned for the spring of 2005 in the volcanic alban hills region southeast of rome, near the summer home of pope john paul ii, as well as for volcanic areas near los alamos, n. m. this article was originally published with the title volcanic sniffing.


if astronomy and outerspace interest you, then this activity set will fascinate you. you ' ll learn about the planets, stars, sun, moon, and even rockets - all through fun, hands - on experiments. activities include using balloons and chemically powered rockets to study rocket propulsion, building a telescope and star map to investigate the stars and constellations, assembling a model of the solar system to about the planets that share it, and more. once you work through all the activities, you will understand how earth ’ s axis and revolution around the sun causes the seasons, how the moon ’ s rotation around earth gives us the phases of the moon, how meteorites formed the craters on the moon, how meteoroids become falling stars, and so much more. includes a full - color, 32 - page experiment book to guide your space exploration. ages 8 and up. warning : choking hazard — children under 8 yrs. can choke or suffocate on uninflated or broken balloons. adult supervision required. keep uninflated balloons from children. discard broken balloons at once. - launch three types of rockets - build a telescope and star map - model the solar system - investigate the revolution and rotation of earth - swing a moon sling - find the man in the moon - recreate lunar and solar eclipses - learn about falling stars - discover how the universe is expanding


an instrument to measure the altitude of an object above a fixed level. generally, mean sea level is used for the reference level. mid - level cloud ( bases generally 2000 - 8000m ), made up of grey, puffy masses, sometimes appearing in parallel waves or bands. an indicatorof mid - level instability. altocumulus can take on various forms such as aclenticularis, ac undulatus, ac castellanus, altocumulus ' mackerel sky '. a middle level cloud with vertical development that forms from altocumulusclouds. it is composed primarily of ice crystals in its higher portions andcharacterised by its turrets, protuberances or crenulated tops. mid - level cloud composed of water droplets and ice crystals. usuallygives the sun a watery or dimly visible appearance. a local wind that flows up the side of valleys due to increased heating alongthe valley walls. often the anabatic wind results in cumulus clouds along theridges either side of the valley. see also katabatic winds. a device used to measure wind speed. the departure of an element from its long - term average for the locationconcerned. for example, if the average maximum temperature for melbourne in june is 14 degrees and on one particular day the temperature only reaches 10 degrees, than the anomaly for that day is - 4. a large scale atmospheric circulation system in which the winds rotate anticlockwise in the southern hemisphere ( clockwise in northern hemisphere ). anticyclones are areas of high atmospheric pressure and are generallyassociated with light winds and stable weather conditions. interchangeablewith high pressure system. rotation in the opposite sense as the earth ' s rotation, i. e., anticlockwise in


the history of pressure measurement 1594 galileo galilei, born in pisa ( italy ), obtains the patent for a machine to pump water from a river for the irrigation of land. the heart of the pump was a syringe. galileo galilei found that 10 meters was the limit to which the water would rise in the suction pump, but had no explanation for this phenomenon. scientists were then devoted to find the cause for this. 1644 evangelista torricelli ( rorr ). italian physicist, filled a tube 1 meter long, hermetically closed at one end, with mercury and set it vertically with the open end in a basin of mercury. the column of mercury invariably fell to about 760 mm, leaving an empty space above its level. torricelli attributed the cause of the phenomenon to a force on the surface of the earth, without knowing, where it came from. he also concluded that the space on top of the tube is empty, that nothing is in there and called it a " vacuum ". 1648 blaise pascal, french philosophei physicist and mathematician, heard about the experiments of torricelli and was searching for the reasons of galileo ' s and torricelli ' s findings. he came to the conviction that the force, which keeps the column at 760 mm, is the weight of the air above. thus, on a mountain, the force must be reduced by the weight of the air between the valley and the mountain. he predicted that the height of the column would decrease which he proved with his experiments at the mountain puy de dome in central france. from the decrease he could calculate the weight of the air. pascal also formulated that this force, he called it " pressure ", is acting uniformly in all directions. 1656 offo von guericke, born in magdeburg / germany. torricellis conclusion of an empty space or " nothingness " was contrary to the doctrine of an omnipresent god and was thus attacked by the church. guericke developed new air pumps to evacuate larger volumes and staged a dramatic experiment in magdeburg by pumping the air out of two metal hemispheres which had been fitted together with nothing more than grease. 8 horses at each hemisphere were not strong enough to separate them. 1661 robert boyle. an anglo - irish chemist, used " j " - shaped tubes closed at one end to study the relationship between the pressure and volume of trapped gas and stated the law of x v = k ( p : pressure, v : volume,


robert boyle. an anglo - irish chemist, used " j " - shaped tubes closed at one end to study the relationship between the pressure and volume of trapped gas and stated the law of x v = k ( p : pressure, v : volume, k : constant ) which means that if the volume of a gas at a given pressure is known, the pressure can be calculated if the volume is changed, provided that neither the temperature nor the amount of gas is changed. 1820 almost 200 years later, joseph louis gay - lussac. french physicist and chemist, detects that the pressure increase of a trapped gas at constant volume is proportional to the temperature. 20 years later, william thomson ( lord kelvin ) defines the absolute temperature mechanical measurement technologies 1843 lucien vidie, french scientist, invented and built the aneroid barometer, which uses a spring balance instead of a liquid to measure atmospheric pressure. the spring extension under pressure is mechanically amplified on an indicator system. employing the indicator method of vidie, eugene bourdon ( founder of the bourdon sedeme company ) patented 1849 the bourdon tube pressure gauge for higher pressures. electrical measurement technologies 1930 the first pressure transducers were transduction mechanisms where the movements of diaphragms, springs or bourdon tubes are part of an electrical quantity. pressure diaphragms are part of a capacitance. the indicator movement is the tap of a potentiometer. 1938 the bonded strain gauges were independently developed by e. e. simmons of the california institute of technology and ac. ruge of massachuseffs institute of technology. simmons was faster to apply for a patent. 1955 the first foil strain gauges came up with an integrated full resistor bridge, which, if bonded on a diaphragm. see opposite stress in the center and at the edge. 1965 the bonding connection of the gauges to the diaphragm was always the cause for hysteresis and instability. in the 1960 ' s, statham introduced the first thin - film transducers with good stability and low hysteresis. today, the technology is a major player on the market for high pressure. 1973 william r. poyle applied for a patent for capacitive transducers on glass or quartz basis, bob bell of kavlico on ceramic basis a few years later in 1979. this technology filled the gap for lower pressure ranges ( for which thin film was not suited ) and is today, also with resist


##cers on glass or quartz basis, bob bell of kavlico on ceramic basis a few years later in 1979. this technology filled the gap for lower pressure ranges ( for which thin film was not suited ) and is today, also with resistors on ceramic diaphragms, the widest spread technology for the sensor age 1967 honeywell research center, minneapolis / usa, 1967 : art r. zias and john egan applied for patent for the edge - constrained silicon diaphragm. 1969. hans w. keller applied for patent for the batch - fabricated silicon sensor. the technology is profiting from the enormous progresses a modern sensor typically weighs 0. 01 grams. if all non - cristalline diaphragms have inherent hysteresis, the precision limit of this item is not detectable by todays means. 2000 the piezoresistive technology is the most universal one. it applies for pressure ranges from 100 mbar to 1500 bar in the absolute, gauge and differential pressure mode. the slow spread of the technology in high volume applications for non - benign media resulted from the inability of us - companies to develop a decent housing. in 30 years, keller has perfected it at costs comparable to any other technology. for more information, please contact... keller at www. keller - druck. com for details of pressure sensors suppliers, click here... home - website - search - suppliers - links - new products - catalogues - magazines problem page - applications - how they work - tech tips - training - events - jobs - register


zooplankton community dynamics ballast water transport as a taxonomic and numeric ' filter ' zooplankton data collected from ballast tanks at the beginning and end of 25 voyages showed an overall decline in total zooplankton abundance during a voyage. mortality within tanks could be caused by a number of factors, including : - lack of settlement substrate - exposure to toxic substances - physiological stress caused by changes in physical conditions in addition, the duration of a voyage or the age of the ballast water is also an important factor, as mortality within tanks appears to increase with time. for example, our data indicated that : • on short voyages ( < 10 days ) survival of zooplankton is unpredictable, but typically high ( both increases and decreases in abundance were recorded ). • on long voyages ( 16 - 22 days ) there were large declines in survivorship ( > 95 % decrease in abundance in all cases. this an important finding because in order to survive, establish, and thus achieve a successful ballast - mediated invasion, an organism must be delivered in adequate densities to increase the chances of encountering a mate and reproducing. this means that shorter coastwise voyages, where survivorship is more variable and the final densities are relatively higher pose a greater ' invasion threat ' than do longer voyages. though these data bring us closer to identifying predictors of overall zooplankton survivorship, identifying individual taxonomic groups that are more likely to become successful invaders remains elusive. survivorship varied both between taxonomic groups and within taxonomic groups for different voyages. thus, we still do not fully understand the extent to which particular taxonomic groups are better able to survive transport in ballast tanks than others. these data strongly point to the need for rigorous ballast water management policies across the board to effectively handle the release of domestic ballast water, particularly that portion of it which has only been subject to short - term transport.


high energy mystery lurks at the galactic centre particle physics and astronomy research council posted : september 22, 2004 a mystery lurking at the centre of our own milky way galaxy - an object radiating high - energy gamma rays - has been detected by a team of uk astronomers working with international partners. their research, published today ( september 22nd ) in the journal astronomy and astrophysics, was carried out using the high energy stereoscopic system ( h. e. s. s. ), an array of four telescopes, in namibia, south - west africa. the galactic centre harbours a number of potential gamma - ray sources, including a supermassive black hole, remnants of supernova explosions and possibly an accumulation of exotic ' dark matter ' particles, each of which should emit the radiation slightly differently. the radiation observed by the h. e. s. s. team comes from a region very near sagittarius a *, the black hole at the centre of the galaxy. according to most theories of dark matter, it is too energetic to have been created by the annihilation of dark matter particles. the observed energy spectrum best fits theories of the source being a giant supernova explosion, which should produce a constant stream of radiation. dr. paula chadwick of the university of durham said, " we know that a giant supernova exploded in this region 10, 000 years ago. such an explosion could accelerate cosmic gamma rays to the high energies we have seen - a billion times more energy than the radiation used for x - rays in hospitals. but further observations will be needed to determine the exact source. " professor ian halliday, chief executive of the particle physics and astronomy research council ( pparc ) which funds uk involvement in h. e. s. s. said ; " science continues to throw out the unexpected as we push back the frontiers of knowledge. " halliday added " the centre of our galaxy is a mysterious place, home to exotic phenomena such as a black hole and dark matter. finding out which of these sources produced the gamma - rays will tell us a lot about the processes taking place in the very heart of the milky way. " however, the team ' s theory doesn ' t fit with earlier results obtained by the japanese / australian cangaroo instrument or the us whipple instrument. both of these have detected high - energy gamma rays from the galactic centre in the past ( observations from 1995 - 2002 ), though not with the same precision as h. e. s. s, and they were unable to


us whipple instrument. both of these have detected high - energy gamma rays from the galactic centre in the past ( observations from 1995 - 2002 ), though not with the same precision as h. e. s. s, and they were unable to pinpoint the exact location as h. e. s. s. has now done, making it harder to deduce the source. these previous results have different characteristics to the h. e. s. s. observations. it is possible that the gamma - ray source at the galactic centre varies over the timescale of a year, suggesting that the source is in fact a variable object, such as the central black hole. the h. e. s. s. team hopes to unravel the mystery with further observations of the galactic centre over the next year or two. the full array of four telescopes will be inaugurated on september 29th 2004, see the h. e. s. s. collaboration the high energy stereoscopic system ( h. e. s. s. ) team consists of scientists from germany, france, the uk, the czech republic, ireland, armenia, south africa and namibia. the h. e. s. s. array over the last few years, the h. e. s. s. collaboration have been building a system of four telescopes in the khomas highland region of namibia, to study very - high - energy gamma rays from cosmic particle accelerators. the telescopes, known as cherenkov telescopes, image the light created when high - energy cosmic gamma rays are absorbed in the atmosphere, and have opened a new energy domain for astronomy. the h. e. s. s. telescopes each feature mirrors of area 107 square metres, and are equipped with highly sensitive and very fast 960 - pixel light detectors in the focal planes. construction of the telescope system started in 2001 ; the fourth telescope was commissioned in december 2003. observations were being made even while the system was being built, first using a single telescope, then with two and three telescopes. while only the complete four - telescope system provides the full performance, the first h. e. s. s. telescope alone was already superior to any of the instruments operated previously in the southern hemisphere. among the first targets to be observed with a two - telescope instrument was the galactic centre. ares 1 - x patch the official embroidered patch for the ares 1 - x rocket test flight, is available for purchase. this beautiful one piece set features the apollo program emblem surrounded by the individual mission logos. the official


home › sparknotes › chemistry study guides › review of gases › gases review test don ' t seem to have. please try a different browser. scroll through the page to review your answers. the correct answer is your incorrect answers ( if any ) are highlighted in if you ' d like to take the test over again, click the reset button at the end of the test. which of the following is a correct interpretation of the ideal gas law? what is the correct relationship between an isolated container of gas doubles in pressure and triples in volume. by what factor does t change? if the volume of a gas is doubled at constant temperature, the factor by which the pressure increases is : a barometer filled with an unknown liquid has a height of 1 m at 1 atm. during stormy weather, the height of the column is observed to rise to 1. 3 m. what is the atmospheric pressure? which of the following are possible units of r? what are the conditions of stp? a container contains 32 grams of gas and 2 grams of gas. if the total pressure of the vessel is 16 atm, what is the partial pressure of the as the average radius of a population of gas molecules increases, how does the factor b of van der waals all of the following are properties of an ideal gas except : the ideal gas law is most valid under these conditions : for the van der waals equation : for the equation pv = nrt, the value of t must be expressed in : which of the following is not a si unit a sample of gas has a volume of 22. 4 l at a temperature of 273 k. how many moles are in the sample? the volume of a sample of gas expands five times at constant pressure. by what factor has the absolute the following reaction produces a sample of gas occupies 100 l at stp. if the absolute temperature is halved while all other conditions are constant, what will be the final volume? of a sample of at 300 k. a closed jar contains 2 moles of and 3 moles of. what is the ratio of the partial pressure of over the total pressure in the jar? the rate of effusion of gas a is four times that of gas b. what is the density of a certain gas at stp is 1. 43 g / l. what is the identity of the gas? one end of a mercury manometer is open to the atmosphere ( tm = 760mmhg ). the other end is connected to a 1 mol sample of that is at 273


43 g / l. what is the identity of the gas? one end of a mercury manometer is open to the atmosphere ( tm = 760mmhg ). the other end is connected to a 1 mol sample of that is at 273 k and occupies 22. 4 l. what is the height of the the maxwell - boltzmann distribution graph plots : james the giant has big shoes to fill. his shoes have a total area of in contact with the ground. unfortunately, james ' feet are not so big. barefoot, his weight is spread over. what is the ratio of the pressure he exerts on the ground barefoot over the pressure he exerts with his shoes on? the " air " in airbags is generated via the decomposition of solid a sample of an ideal gas is compressed at constant temperature. what happens to the average kinetic energy of the molecules? a piston compresses a gas at constant temperature. initially the gas occupied 1 l and was at a pressure of 1 atm. after compression, the gas occupies 0. 1 atm. what is the pressure of the compressed gas? a collaborator from a foreign country reports that the value of has probably used units of " woozle " for which of the following variables : avogadro ' s number is : the following maxwell - boltzmann distribution plot was measured for two gases a and b at the same a rigid container holds a mixture of gases. within this mixture, the partial pressure of is 400 torr. if an additional quantity of gas is injected into the container such that the total pressure of the container rises by 760 torr, what is the change in the partial pressure of? assume that the temperature of the container ' s contents stays constant. if the pressure of a gas doubles and the temperature quadruples, by what factor does the volume change? which of the following are possible units for pressure? the following maxwell - boltzmann distribution plot was measured for a gas at two temperatures a and b : for the following calculation of, the molar mass ( mm ) should be expressed in what units? by what significant numerical value are boltzmann ' s constant ( k ) and the gas constant ( r ) related? the pressure of a gas is tripled while the volume is halved. by what factor does the temperature increase? the gas constant r : one end of a manometer is sealed off to a vacuum. the other end of the manometer is connected to a pressurized gas. the height of the liquid column is indicative of :


what factor does the temperature increase? the gas constant r : one end of a manometer is sealed off to a vacuum. the other end of the manometer is connected to a pressurized gas. the height of the liquid column is indicative of : a sample of and a sample of both have a temperature of 330 k. what is the ratio of the average kinetic energy of the over that of the the density of a gas at stp is 0. 089 g / l. what is the molar mass of the gas? the following maxwell - boltzmann distribution plot was measured for two gases a and b at temperatures gaseous methane ( ) burns completely in gaseous oxygen to produce carbon dioxide gas and water liven up your study sesh with one of these playlists! enjoy the tunes! this expertly - crafted playlist is brought to you by chris pine and zoe saldana heat up the red carpet! auntie sparknotes can help! click here for simple, sexy makeup tricks! see every single look from the met gala! we already dib ' sed genghis khan. travel back in time! from super cute to super bad! what do you think? when you don ' t look like j - law. what did star trek get wrong? get our free nook reading apps when your books and teachers don ' t make sense, we do. ©2013 sparknotes llc, all rights reserved


knol dl, loisel p, van mechelen w. multidisciplinary rehabilitation for subacute low back pain : graded activity or workplace intervention or both? a randomized controlled trial. spine. 2007 ; 32 : 291 - 298. chou r, qaseem, snow v, casey d, cross jt jr., shekelle p, et al. diagnosis and treatment of low back pain : a joint clinical practice guideline from the american college of physicians and the american pain society. ann intern med. 2007 ; 147 : 478 - 491. chou r, loeser jd, owens dk, rosenquist rw, et al. american pain society low back pain guideline panel. interventional therapies, surgery, and interdisciplinary rehabilitation for low back pain : an evidence - based clinical practice guideline from the american pain society. spine. 2009 ; 34 ( 10 ) : 1066 - 77. | review date : 7 / 23 / 2011 | reviewed by : david zieve, md, mha, medical director, a. d. a. m. health solutions, ebix, inc. ; and c. benjamin ma, md, assistant professor, chief, sports medicine and shoulder service, ucsf department of orthopaedic surgery. the information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. a licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. call 911 for all medical emergencies. links to other sites are provided for information only - - they do not constitute endorsements of those other sites. © 1997 - a. d. a. m., inc. any duplication or distribution of the information contained herein is strictly prohibited.