Studies of the geographic variation of colon and rectal (colorectal) cancer mortality rates in the U.S. have long indicated that they are primariliy linked to solar ultraviolet-B (UVB) radiation: the more UVB in summer, the lower the mortality rate.
The hypothesis to explain this result is that UVB radiation produces vitamin D in the skin, and vitamin D acts to reduce the risk of colorectal and over a dozen other types of cancer. One major study found that intake of 150 IU/day of vitamin D was associated with a reduction by half in incidence of colon cancer, a result that was statistically significant. However, some studies that have investigated the link between dietary sources of vitamin D and colorectal cancer have found a smaller degree of risk reduction comparing the highest versus lowest levels of dietary vitamin D.
In a review of the literature published in the current issue of Nutrition and Cancer, Drs. William Grant and Cedric Garland report that the reason for the sometimes weak link between dietary sources of vitamin D and colorectal cancer incidence or mortality rates is that dietary sources often cannot supply enough vitamin D to be effective in quantities ordinarily consumed. In most such studies, the highest quartile or quintile of those studied consumed over 150-370 I.U./day from dietary sources. That was sufficient in some cases to provide a 10-50% reduction in colorectal cancer risk, but not always at a statistically significant level. However, studies that considered vitamin D intake from both diet and supplements for which the highest levels were over 500 I.U./day found 30-60% risk reduction for the highest versus lowest levels, and the results were uniformly tatistically significant.
Oxygen can wake up dormant bacteria for antibiotic attacks
08.12.2016 | Penn State
NTU scientists build new ultrasound device using 3-D printing technology
07.12.2016 | Nanyang Technological University
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
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