Biology / Biochemistry / Bioengineering
Altered Perceptions (Mar 2017)
The human brain is constantly abuzz with electrical activity as brain cells, called neurons, respond to sensory input and give rise to the world we perceive. Six particular regions of the brain, called face patches, contain neurons that respond more to faces than to any other type of object. New research from Caltech shows how perturbations in these face cells alter perception, answering a longstanding question in cognitive science.
The genomes of cancer cells—cells that do not obey signals to stop reproducing—are riddled with genetic mutations, causing them inadvertently to make many dysfunctional proteins. Like all other cells, cancer cells need to be vigilant about cleaning themselves up in order to survive.
Small but Mighty: Fruit Fly Muscles (Jan 2017)
Fruit flies are capable of impressive aerial maneuvers, as is grudgingly acknowledged by anyone who has unsuccessfully tried to swat away one of the familiar kitchen pests. Interestingly, the flies perform these nimble evasive movements using only 12 flight muscles, each controlled by one brain cell, or neuron. In comparison, hummingbirds can produce almost identical aerial patterns but use 100 times more neurons per muscle.
Fixating on Faces (Jan 2017)
When we are walking down a crowded street, our brains are constantly active, processing a myriad of visual stimuli. Faces are particularly important social stimuli, and, indeed, the human brain has networks of neurons dedicated to processing faces. These cells process social information such as whether individual faces in the crowd are happy, threatening, familiar, or novel.
Visualizing Gene Expression with MRI (Dec 2016)
Genes tell cells what to do—for example, when to repair DNA mistakes or when to die—and can be turned on or off like a light switch. Knowing which genes are switched on, or expressed, is important for the treatment and monitoring of disease. Now, for the first time, Caltech scientists have developed a simple way to visualize gene expression in cells deep inside the body using a common imaging technology.
Protein Disrupts Infectious Biofilms (Dec 2016)
Many infectious pathogens are difficult to treat because they develop into biofilms, layers of metabolically active but slowly growing bacteria embedded in a protective layer of slime, which are inherently more resistant to antibiotics.
Parkinson’s Disease Linked to Microbiome (Dec 2016)
Caltech scientists have discovered for the first time a functional link between bacteria in the intestines and Parkinson’s disease (PD). The researchers show that changes in the composition of gut bacterial populations—or possibly gut bacteria themselves—are actively contributing to and may even cause the deterioration of motor skills that is the hallmark of this disease.
Turning Back the Aging Clock (Nov 2016)
Researchers from Caltech and UCLA have developed a new approach to removing cellular damage that accumulates with age. The technique can potentially help slow or reverse an important cause of aging.
The human body produces T cells to recognize and fight disease. Each T cell has a unique T cell receptor (or TCR) on its surface that surveils small fragments of proteins presented by other cells. Upon detecting evidence of cancer or infection, a subset of T cells binds the diseased cells and orchestrates their elimination. When tumors and infections cannot be eradicated naturally, researchers employ immunotherapies to boost the immune system’s effectiveness.
Hard-Wiring Memories (Oct 2016)
Many people remember exactly what they were doing on September 11, 2001, and some even easily remember exactly what they ate for lunch yesterday. Memories are formed when the neural networks that are active during an event become hard-wired into the cellular machinery of our brain.
Seeing Sound (Oct 2015)
A busy kitchen is a place where all of the senses are on high alert—your brain is processing the sound of sizzling oil, the aroma of spices, the visual aesthetic of food arranged on a plate, the feel and taste of taking a bite. While these signals may seem distinct and independent, they actually interact and integrate together within the brain’s network of sensory neurons.
Astronomy / Planetary Science
Fast radio bursts, or FRBs, are mysterious flashes of radio waves originating outside our Milky Way galaxy. A team of scientists, jointly led by Caltech postdoctoral scholar Vikram Ravi and Curtin University research fellow Ryan Shannon, has now observed the most luminous FRB to date, called FRB 150807.
Dark Matter Dominates in Nearby Galaxy (Nov 2015)
Dark matter is called “dark” for a good reason. Although they outweigh particles of regular matter by more than a factor of 5, particles of dark matter are elusive. Their existence is inferred by their gravitational influence in galaxies, but no one has ever directly observed signals from dark matter.
Engineering / Materials Science / Applied Physics
Building Better Batteries (Dec 2016)
Lithium-ion batteries, widely used in devices ranging from electric cars to iPhones, are composed of a cathode made from a positively charged lithium compound and an anode composed of negatively charged carbon. Ideally, anodes would be made of lithium metal, which can store more energy than carbon. However, lithium metal anodes have a serious flaw—over time, the lithium metal grows dendrites, tiny needle-like branching structures that can grow through the battery causing it to short-circuit or even explode.
Atomic Fractals in Metallic Glasses (Sep 2015)
Metallic glasses are very strong and elastic materials that appear with the naked eye to be identical to stainless steel. But metallic glasses differ from ordinary metals in that they are amorphous, lacking an orderly, crystalline atomic arrangement. This random distribution of atoms, which is the primary characteristic of all glass materials (such as windowpanes and tableware), gives metallic glasses unique mechanical properties but unpredictable internal structure.
Taking Dinosaur Temperatures with Eggshells (Oct 2015)
Researchers know dinosaurs once ruled the earth, but they know very little about how these animals performed the basic task of balancing their energy intake and output—how their metabolisms worked.