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Nanocrystals Not Small Enough to Avoid Defects

By Guest PostDecember 15, 2012Scienceals, berkeley lab, bin chen, computer simulation, crystal, defect, dislocation, gas turbine, grains, high pressure, jet engine, jialin lei, jinyuan yan, katie lutker, mechanical properties, metal, nanocrystal, nanocrystalline nickel, nanometer, nickel, non metal, plastic deformation, protective coating, resistance, selva vennila raju, stress, ultraviolet light, waruntorn kanitpanyacharoen

Berkeley Lab Scientists at Advanced Light Source Show Dislocations Can Be Induced by Pressure in Ultrafine Nanocrystals

Nanocrystals as protective coatings for advanced gas turbine and jet engines are receiving a lot of attention for their many advantageous mechanical properties, including their resistance to stress. However, contrary to computer simulations, the tiny size of nanocrystals apparently does not safeguard them from defects.

In a study by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab)and collaborators from multiple institutions, nanocrystals of nickel subjected to high pressure continued to suffer dislocation-mediated plastic deformation even when the crystals were only three nanometers in size. These experimental findings, which were carried out at Berkeley Lab’s Advanced Light Source (ALS), a premier source of X-rays and ultraviolet light for scientific research, show that dislocations can form in the finest of nanocrystals when stress is applied. (more…)

New Insights into How Genetic Differences among Individuals Influence Breast Cancer Risk from Low-Dose Radiation

By Guest PostOctober 17, 2012Health, Scienceandy wyrobek, antoine snijders, berkeley lab, breast cancer, cancer risk, cellular, cellular proliferation, chemical therapy, ct scan, department, dna repair, energy, gene, genetic makeup, gland cancer, immune response, ionizing radiation, joe gray, low dose, mammary tissue, mechanism, mice, non radiation, radiotherapy, resistance, risk, scientist, strain, survival outcome, therapy, tissue mechanism, tissue stress, woman

Berkeley Lab research could lead to new ways to ID women who have higher risk of breast cancer from low-dose radiation

Scientists from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have identified tissue mechanisms that may influence a woman’s susceptibility or resistance to breast cancer after exposure to low-dose ionizing radiation, such as the levels used in full-body CT scans and radiotherapy.

The research could lead to new ways to identify women who have higher or lower risks of breast cancer from low-dose radiation. Such a predictive tool could help guide the treatment of cancer patients who may be better served by non-radiation therapies. (more…)

A New Tool to Attack the Mysteries of High-Temperature Superconductivity

By Guest PostJune 8, 2012Scienceabsolute zero, advanced light source, alessandra lanzara, als, band structure, bardeen cooper schrieffer, bcs theory, beams of xrays, Berkeley, berkeley lab, bi2212, christopher smallwood, conventional superconductors, cooper pairs, dung hai lee, electric current, electric grids, electrons, energy savings, femtosecond scale pulses, high tc, high temperature, joseph orenstein, msd, quasiparticles, relaxation process, resistance, superconductivity, synchrotron light sources, through frequency, transmission, ultrafast laser arpes, university of california

Berkeley Lab researchers use an ultrafast laser to better understand high-temperature superconductors

Superconductivity, in which electric current flows without resistance, promises huge energy savings – from low-voltage electric grids with no transmission losses, superefficient motors and generators, and myriad other schemes. But such everyday applications still lie in the future, because conventional superconductivity in metals can’t do the job.

Although they play important roles in science, industry, and medicine, conventional superconductors must be maintained at temperatures a few degrees above absolute zero, which is tricky and expensive. Wider uses will depend on higher-temperature superconductors that can function well above absolute zero. Yet known high-temperature (high-Tc) superconductors are complex materials whose electronic structures, despite decades of work, are still far from clear. (more…)

What Bacteria Don’t Know Can Hurt Them

By Guest PostJanuary 20, 2012Scienceactual infections, amruta joshi datar, antibiotic, antibiotic resistance, antibiotic sensitive bacteria, antibiotic targets, bacteria, bacteria in biofilms, bacterial functions, biofilm, cells, chronic wounds, cystic fibrosis, dao nguyen, elizabeth bauerle, infection, karlyn beer, lungs, mcgill university, metabolism, microbiologist, natural environment, nutrient, oxygen, paradox, pradeep singh, radicals, resistance, richard siehnel, starvation, starved bacteria, toxic forms, toxic radicals

Many infections, even those caused by antibiotic-sensitive bacteria, resist treatment. This paradox has vexed physicians for decades, and makes some infections impossible to cure.

A key cause of this resistance is that bacteria become starved for nutrients during infection. Starved bacteria resist killing by nearly every type of antibiotic, even ones they have never been exposed to before. (more…)

Vaccine for Urinary Tract Infections is One Step Closer

By Guest PostNovember 14, 2010Health, Scienceantibiotic, bacteria, bacteria genes, common treatments, ecoli, ecoli bacteria, erin c hagan, fluoroquinolones, gary j faerber, harry l t mobley, resistance, urinary tract infections, urology, utis, women

*Study sheds light on what E. coli genes are doing inside the body during infection*

E. coli bacteria. Image credit: Amy Simms, Ph.D

ANN ARBOR, Mich. — Urinary tract infections are a painful, recurring problem for millions of women. They are also getting more dangerous as bacteria develop resistance to the most common treatments.

Scientists from the University of Michigan have moved one step closer to a vaccine that could prevent a majority of urinary tract infections, which are caused by E. coli bacteria. Using a genetic technique rarely used to look at infections in human hosts, the researchers studied how the E. coli bacteria operate and discovered key differences between how the bacteria’s genes behave in women and how they behave in mice used in experiments.

Their findings, published online Nov. 11 in PLoS Pathogens, could lead to developments that would save billions in health care costs and millions of doctors’ visits and hospitalizations from urinary tract infections each year. (more…)

Tag Archives: resistance

Nanocrystals Not Small Enough to Avoid Defects

New Insights into How Genetic Differences among Individuals Influence Breast Cancer Risk from Low-Dose Radiation

A New Tool to Attack the Mysteries of High-Temperature Superconductivity

What Bacteria Don’t Know Can Hurt Them

Vaccine for Urinary Tract Infections is One Step Closer