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Shown promise in early trials in patients with systemic lupus. Some other therapies under investigation include molecules designed to block production of anti-DNA autoantibodies or to induce those antibodies to bind to decoy compounds that would trap them and provoke their degradation. An example of such a decoy is a complex consisting of four short DNA strands coupled to an inert backbone. Although the last idea is intriguing, I have to admit that the effects of introducing such decoys are apt...

The Diagnostic Challenge

Physicians who suspect that a patient, whether female or male, has lupus continue to be hampered by the lack of a conclusive test. Because immunological self-attack may underlie many illnesses, even a classic sign of lupus the presence of antinuclear autoantibodies does not unmistakably diagnose this disorder. In the absence of a sure test, doctors might gather information from a variety of sources, including not only laboratory tests but also the patient's description of current symptoms and...

Pathways To Disease

The processes underlying lupus are known in a general way (flowchart). But many of the details remain murky, such as how hormones and environmental triggers precipitate immune attacks on the body's tissues. For one, they tend to recruit immune system entities known as complement molecules, which can directly harm tissue. The complexes, either by themselves or with the help of the complement molecules, also elicit an inflammatory response. This response involves an invasion by white blood cells...

Fuelcelldriven Design Freedom

General Motors's new Sequel fuel-cell concept vehicle (right) contains enou drive 300 miles, the minimum acceptable range. It does so by fitting about seven kilograms of hydrogen into its 11-inch-thick skateboard chassis (bottom left), which also contains almost all the crossover SUV's operating systems. The Sequel demonstrates how all-electric power trains will free auto designers to rethink the configuration of future models. Because strictly mechanical components can be replaced by fully...

Response Effectiveness

Simulations allowed people to withdraw to their homes because they felt ill or were following officials' instructions. Withdrawal could be early, before anyone became contagious, or never, meaning people continued moving about unless they died. Late withdrawal, 24 hours after becoming contagious, was less effective than early withdrawal, which prevented an epidemic without other intervention. Official responses included doing nothing, or targeted vaccination and quarantine with unlimited...

Targeted Vaccination And Quarantine Starting

INFECTED 1,281 QUARANTINED 0 VACCINATED 0 DEAD 0 INFECTED 2,564 QUARANTINED 29,910 VACCINATED 30,560 DEAD 312 DAY 70 EPIDEMIC UNCONTAINED OR CONTAINED INFECTED 2,564 QUARANTINED 36,725 VACCINATED 37,207 DEAD 435 INFECTED 2,564 QUARANTINED 36,725 VACCINATED 37,207 DEAD 435 INTERVENTION KEY No vaccine 10-day delay 7-day delay 4-day delay

Building Social Networks

Constructing a social network for a household of two adults and two children starts by identifying their contacts with other people throughout a typical day. This diagram shows where the household members go and what they do all day but reveals little about how their individual contacts might be interconnected or connected to others.

Dailyactivities

Setting the population in motion requires assigning locations to every household's activities. Land-use data for buildings, parking lots, parks and other places were associated with 180,000 locations in the model, providing estimates of the number of people performing various types of activities there. Activities were anchored to individuals' work or school locations, and then places were chosen for additional activities, such as grocery shopping or recreation, taking into account their...

Maximum Solar Radiation In Northern Hemisphere

Although scientists do not fully understand why, global concentrations of these greenhouse gases respond mainly to changes that occur during summer in the Northern Hemisphere, the time of year when the North Pole is pointed most directly at the sun. Wobble in the earth's axis of rotation, known as precession, is one of the three orbital cycles that account for sunlight variations in the Northern Hemisphere. Like a toy top about to fall, the earth's axis traces imaginary circles in...

Inside Fuel Cells

A fuel cell operates like a refuelable battery it will generate electricity as long as it is supplied with hydrogen and oxygen. A proton-exchange membrane (PEM) fuel cell (right) is composed of two thin, porous electrodes, an anode and a cathode, separated by a solid polymer membrane electrolyte. Platinum-based catalysts coat one side of each electrode. After hydrogen atoms enter the cell (1), the anode catalyst splits them into electrons and protons (2). The electrons move along an external...

Pharmaceuticals

To deliver genes into cells, scientists rely on engineered viruses, but these germs often provoke immune responses and make them potentially lethal. New silica nanoparticles with organic components may prove effective nonviral DNA carriers. Chemists at the University at Buffalo found that the electric charge on these nanoparticles held and compacted the DNA, protecting it from enzymatic digestion in cells. The organic components also render normally rigid silica nanoparti-cles more flexible and...

Updated Every Weekday

To find these recent additions to the site Evidence for Milky Way's Long-Theorized Stellar Graveyard Found several years that a supermassive black hole called Sagittarius A* resides at the center of the Milky Way galaxy. New data indicate that a swarm of smaller black holes that have accumulated over billions of years may surround it. The findings suggest that the smaller black holes will eventually fall into Sagittarius A*, elucidating how such behemoths grow. 3 How Geckos Keep Their Sticky...

Big Bang

Baffled by the expansion of the universe You're not alone. Even astronomers frequently get it wrong By Charles H. Lineweaver and Tamara M. Davis 36 SCIENTIFIC AMERICAN MARCH 2005 COPYRIGHT 2005 SCIENTIFIC AMERICAN, INC. INFLATING BALLOON is a good analogy for understanding the expansion of the universe. The galaxies on the surface of the balloon are effectively at rest, and yet as the universe expands, the distance between any two galaxies increases. The galaxies themselves do not increase in...

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ENCYCLOPEDIA OF LIFE SUPPORT 5VSTCM5 EOLS5 Avirtual dynamic library equivalent to 00 rtJtumei WITH CONTRIBUTIONS FROM THOUSANDS OF SCHOLAR'S, FROM CJVTR 100 tDUMTRIES AND EJDlTEti amp YWER JDO SUBICT EXPERT Institutional libraries are invited to register at www.eolis.net using the promotional cade TA17452 to obtain free trial access for 5 months. l Jkihnf k-iih iWrtivd jWI_i J J wt Jwdr. The 10 counties with the largest numbers of gays and lesbians 1. Los Angeles 2. Cook, Illinois Chicago 3....

Timing lupus

A 24-year-old woman undergoes medical evaluation for kidney failure and epilepsylike convulsions that fail to respond to antiepileptic drugs. Her most visible sign of illness, though, is a red rash extending over the bridge of her nose and onto her cheeks, in a shape resembling a butterfly. A 63-year-old woman insists on hospitalization to determine why she is fatigued, her joints hurt, and breathing sometimes causes sharp pain. Ever since her teen years she has avoided the sun, which raises...

Bcells Gone Wrong

B lymphocytes normally respond only to foreign substances, or antigens, such as bacteria. But in people with lupus the cells react to the body's own molecules, generating antibodies that bind to those self-antigens and then accumulate in tissues. There the antibody-antigen complexes lead to tissue damage. Several therapies under study for lupus aim to delete B cells or to block one or another of the molecular interactions that lead to antibody production and tissue injury. Red arrows in the...

Simulated Smallpox Attacks

EpiSims animations depict simulated outbreaks and the effects of official interventions. In the still frames below, vertical lines indicate the number of infected people present at a location, and color shows the percentage of them who are contagious. In both scenarios shown, smallpox is released at a university in central Portland, but the attack is not detected until victims start experiencing symptoms 10 days later. The left-hand images show no public health response as a baseline. In the...

Dreams

Szigeti Tesla Motor Drawing

The father of today's AC electrical system and other key inventions, often failed to bring his visionary ideas to real-world fruition When members of the Chicago Commercial Club arrived to hear a lecture by the famed electrical inventor Nikola Tesla on May 13, 1899, they were startled by the sight of an artificial lake sitting in the middle of the auditorium. Everyone knew that Tesla the man who had devised the alternating-current AC system that brought electricity into people's homes and...

Local Social Network

A social network emerges by drawing lines to represent connections within the household a and from the household members to their direct contacts b . Connecting those individuals to their own circle of contacts c and those to the next generation of contacts d enlarges the network. Long-distance connections show contacts who also know each other. Yet no one in this network has more than 15 direct contacts, meaning none is a highly connected hub of society. One insight from this work is that so...

By Patricia D Moehlman

Patricia Moehlman

After admiring equids for thousands of years, humans may be driving the last populations of wild zebra, asses and horses to extinction. SCIENTIFIC AMERICAN Volume 292 Number 3 Tsunami relief does not replace development. The tsunami's human and geophysical scars. Cold fusion is still lukewarm. Personalized nutrition. 34 A buoyant alternative to satellites. How do astronauts stay clean By the Numbers The gay population. 94 Data Points Terrorism and civil rights. He shoots, he scores...

The Last Wild Equids

African Wild Ass

Equus ferus przewalskii Takhi EXTINCT IN THE WILD Reintroduction site Equus ferus przewalskii Takhi EXTINCT IN THE WILD Reintroduction site Equus burchellii Plains zebra LEAST CONCERN ONLY SIX SPECIES of equids remain in the wild three asses and three zebra. A seventh species Przewalski's horse, or takhi is extinct in the wild, but programs are well under way to reintroduce these animals, which have been preserved in zoos and parks, to their native habitat in Mongolia. Colored areas indicate...

New Analysis Weighs In On Where Hippos Come From By Kate Wong

It might look docile lolling among the water lilies, but bad-tempered and surprisingly swift on terra firma, the hippopotamus has a deservedly fearsome public image in its African homeland. It also has a formidable reputation among evolutionary biologists the beast has defied attempts to pinpoint its origin for nearly two centuries. To that end, recent findings may finally put the hippo in its place. With its gaping maw, hairless body and A PLACE FOR HIPPOS Evolutionary biologists think they...

Analyzing Metabolism For Personalized Nutrition By Gunjan Sinha

Some people can slurp cabbage soup for a week and lose only a few ounces, while others on the same spartan regimen lose 10 pounds. But what if you could measure your metabolism and get a prescription for a customized diet Metabonomics may do just that. It is one of the latest offshoots of the -omics revolution after genomics genes and proteomics proteins . With the understanding that some diseases such as obesity COMFORT FOOD In a new field called...