878,407 articles

A Genetic Trigger For The Cambrian Explosion Unraveled?

A team of scientists has developed a novel methodological approach in evolutionary studies. Using the method they named 'genomic phylostratigraphy', its authors shed new and unexpected light on some of the long standing macroevolutionary issues, which have been puzzling evolutionary biologists since Darwin.

Back To School: Cramming Doesn't Work In The Long Term

Psychologists have been assessing how well various study strategies produce long-term learning, and it appears that some strategies really do work much better than others. Surprisingly "massing" all the study on a single topic into a single session reduces long-term retention. It's better to leave it alone for a while and then return to it.

Molecules Line Up To Make The Tiniest Of Wires

As technology gets smaller and smaller, the computer industry is facing the complex challenge of finding ways to manufacture the minuscule components necessary. Now scientists have demonstrated a technique for producing conductive nano-wires on silicon chips. While the new process could provide the solution for computer manufacturers looking for ways of increasing the speed and storage capacity of...

Pancreatic Cancer Fights Off Immune Attack

Scientists have discovered that pancreatic cancer attracts regulatory T cells, which suppress the activity of immune cells. In this way, the tumor might escape its destruction by the immune system. The ability to discriminate between friend and foe or between "self" and "foreign" is vital for a functioning immune system. There are numerous protective mechanisms at work to save the body's own...

Polycystic Ovary Syndrome: 1 In 15 Women Affected Worldwide And Burden Likely To Increase

The diverse and complex female endocrine disorder polycystic ovary syndrome (PCOS), which affects 1 in 15 women worldwide, is a major economic health burden that is likely to expand together with obesity, conclude authors of a recent article. Many body systems are affected in PCOS, resulting in several health complications, including menstrual dysfunction, infertility, hirsutism (excessive body...

Volcanoes Key To Earth's Oxygen Atmosphere

A switch from predominantly undersea volcanoes to a mix of undersea and terrestrial ones shifted the Earth's atmosphere from devoid of oxygen to one with free oxygen, according to geologists. Before 2.5 billion years ago, the Earth's atmosphere lacked oxygen. However, biomarkers in rocks 200 million years older than that period, show oxygen-producing cyanobacteria released oxygen at the same...

China Says Work Under Way to Mitigate Space Junk (SPACE.com)

SPACE.com - The Chinese government is implementing a wide series of measures to reduce the amount of debris left in orbit by Chinese rockets and satellites, and to develop a space-surveillance tool to determine what is in orbit, Chinese space-debris experts said.

Inside The Brain Of A Crayfish

Neurophysiology researchers commonly use crustaceans to try to gain basic understanding of the nervous systems of creatures in general, and, wherever possible, for extrapolating what they find to a basic understanding of the much more complex human brain. All animals, from single-celled amoebas to humans, use similar cellular processes to interpret their olfactory environment.

Melanoma Drug Activates Immune Cells To Fight Cancer

A new study shows that an important drug used in the treatment of malignant melanoma has little effect on the melanoma cells themselves. Instead, it activates immune-system cells to fight the disease. The drug, called interferon alpha, is used to clean up microscopic tumor cells that may remain in the body following surgery for the disease. It is the only drug approved for this purpose.

Molecular Pathway May Predict Chemotherapy Effectiveness

A common molecular pathway could help physicians predict which lung cancer patients will benefit from chemotherapy drugs, according to new research. Known as the retinoblastoma (RB) tumor suppressor, this fundamental molecule regulates cell proliferation in the body. Research has shown that the RB pathway is either entirely inactive or altered in most human cancers. Scientists are beginning to use...

Surprising New Role For Proteins In Sister Chromatid Cohesion

Scientists reveal a surprising new role for tDNAs and RNA polymerase III-associated proteins in sister chromatid cohesion. Sister chromatid cohesion (the binding together of the two identical copies of each chromosome that are formed during replication) helps to ensure that chromosomes are accurately segregated during the anaphase of the cell cycle. Sister chromatid cohesion is mediated by a...

Teenagers' Use Of Cell Phones After Bedtime Contributes To Poor Sleep

Cell phone use after bedtime is surprisingly prevalent among adolescents, and its use is related to increased levels of tiredness after one year. According to the results, only 38 percent of the subjects never used their cell phones after bedtime. Using the cell phone after bedtime about once a week increased the odds of being "very tired" by 3.3, and those who used it more than once a week were...