558 results found for 18-22-year-olds

The techniques and concepts that have resulted in the identification and isolation of embryonic stem cells have come from studies with mouse teratocarcinomas. Embryonic stem cells isolated from normal mouse embryos may be grown in tissue culture and....

It is now axiomatic that, no matter what its causes, cancer ultimately arises from the malfunction of genes. A number of clues prefigured this paradigm: the persistence of the malignant phenotype through countless cell divisions; the mutagenicity of....

The epidemiology of Helicobacter pylori continues to be an area of discovery and controversy in the 21st century. The transmission of this bacterium from mother to child allows Helicobacter DNA to mimic the evolution of maternal mitochondria DNA. B....

Infectious microbes collectively represent the strongest selective pressure operating on our species, and over hundreds of millions of years, drove the evolution of the sophisticated immune system we have today. While the general outlines of immune ....

Flies challenged with bacteria or fungi rapidly transcribe a battery of genes encoding potent antimicrobial peptides which oppose the invading microorganisms. Genetic analysis has identified two signaling cascades which control their expression: (1)....

Despite enormous advances in structural studies of biological systems we are frequently left without a clear structure-function correlation and cannot fully describe how different systems actually work. This introduces a major challenge for computer....

The broad outlines of the secretory pathway were established by pioneering EM and cell fractionation experiments conducted by George Palade in the 1960s. Beginning in the mid 1970s and early 80s, my laboratory isolated a series of conditionally leth....

Astrophysical objects are able to accelerate atomic nuclei to energies 10^7 times more than man made accelerators such as LHC. _Particles arrive at earth from space with energies as great as 50 joules, a macroscopic energy in a microscopic particle.....

Spintronics is a new field of research which exploits the influence of the electron spin on electronic transport. It is well known for the giant magnetoresistance of the magnetic multilayers and its application to increase the capacity of the hard d....

During the entire 20th century, physical sciences have advanced to such a degree that we can extrapolate how they can be applied, even in a fairly distant future.  Even if we leave open the (likely) possibility of spectacular new discoveries and inv....

David discusses a few of the questions facing fundamental physics that might be answered before the 100th Lindau meeting in 2050.

The worldÍs supply of Helium gas comes primarily from alpha decay in rocks. The most abundant supply is in the American Southwest where it is trapped with methane is natural gas wells. That supply is estimated to last a mere 25 years. It took 4.7 bi....