Science & Technology

The instructions for building all of the body’s proteins are contained in a person’s DNA, a string of chemicals that, if unwound and strung end to end, would form a sentence 3 billion letters long.

Four University of Pennsylvania graduate students have been named to the inaugural class of Emerging Leaders in Science and Society Fellows.  ELISS is sponsored by the American Association for the Advancement of Science.

Skin provides a first line of defense against viruses, bacteria and parasites that might otherwise make people ill. When an injury breaks that barrier, a systematic chain of molecular signaling launches to close the wound and re-establish the skin’s layer of protection.

Evolution does not operate with a goal in mind; it does not have foresight. But organisms that have a greater capacity to evolve may fare better in rapidly changing environments. This raises the question: does evolution favor characteristics that increase a species’ ability to evolve?

With a gift of $15 million, University of Pennsylvania trustee emeritus P. Roy Vagelos, C’50, Hon’99, and his wife, Diana, parents ’90, are continuing to ensure Penn’s leadership in energy research by endowing two professorships dedicated to this critically important field.

It’s no coincidence that the expression “to leave a bitter taste in one’s mouth” has a double meaning; people often have strong negative reactions to bitter substances, which, though found in healthful foods like vegetables, can also signify toxicity. For this reason, the ability to sense bitterness likely played an important role in human evolution.

For solar panels, wringing every drop of energy from as many photons as possible is imperative.  This goal has sent chemistry, materials science and electronic engineering researchers on a quest to boost the energy-absorption efficiency of photovoltaic devices, but existing techniques are now running up against limits set by the laws of physics.  

An interdisciplinary team of University of Pennsylvania researchers has already developed a technique for controlling liquid crystals by means of physical templates and elastic energy, rather than the electromagnetic fields that manipulate them in televisions and computer monitors. They envision using this technique to direct the assembly of other materials, such as nanoparticles.  

For years, scientists have observed that tumor cells from certain breast cancer patients with aggressive forms of the disease contained low levels of mitochondrial DNA. But, until recently, no one was able to explain how this characteristic influenced disease progression. 

Some people are deeply religious and others not at all. Evolutionary psychologists are interested in determining the functions of religiosity in social life that lead to this diversity.