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Imagine a single particle, only one-tenth the diameter of a bacterium, whose miniscule jiggles induce sustained vibrations in an entire mechanical device some 50 times larger. By taking clever advantage of the interplay between light, electrons on the surface of metals, and heat, researchers at the National Institute of Standards and Technology (NIST) have for the first time created a plasmomechanical oscillator (PMO), so named because it tightly couples plasmons—the collective oscillations of electrons at the surface of a metal nanoparticle—to the mechanical vibrations of the much larger device it’s embedded in.

The entire system, no bigger than a , has myriad technological applications. It offers new ways to miniaturize mechanical oscillators, improve communication systems that depend on the modulation of , dramatically amplify extremely weak mechanical and electrical signals and create exquisitely sensitive sensors for the tiny motions of nanoparticles.

NIST researchers Brian Roxworthy and Vladimir Aksyuk described their work in a recent issue of Optica.

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S cientists have claimed an important breakthrough in the battle against Alzheimer’s after neutralising the most significant gene responsible for the disease for the first time.

A team in California successfully identified the protein associated with the high-risk apoE4 gene and then manage to prevent it damaging human neuron cells.

The study could open the door to a potential new drug capable of halting the disease, however the researchers have urged caution because so far their compound has only been tried on collections of cells in a laboratory.

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Blood stem cells are produced in the bone marrow, yet new evidence from mice studies suggests that proteins produced in the liver help maintain the production of these critical stem cells from afar. Haematopoietic stem cells (HSCs), which differentiate into various blood cells, are largely produced and maintained by specialised cells that also reside in the bone marrow. However, emerging evidence hints that HSC behaviour is affected via long-range signals originating from a distant part of the body in mammals. To pinpoint the origins of these mysterious signals, researchers investigated which organs in mice produced a key protein called haematopoietic cytokine thrombopoietin which is known to help maintain HSCs, called haematopoietic cytokine thrombopoietin (TPO). The protein, it emerged, was enriched in osteoblasts, mesenchymal stromal cells, and the liver. The researchers found that knocking out TPO production in osteoblasts and mesenchymal stromal cells had little effect on the maintenance of HPCs. However, when they blocked production of TPO in liver cells, this resulted in a 24-fold reduction of HPCs in the bone marrow. The findings appear in the journal Science.

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Will open avenues for drug discovery

Scientists have developed a new blood test for Alzheimer’s disease that can detect early indicators of the disease long before the first symptoms appear in patients. The blood test would thus open the door to new avenues in drug discovery, said the researchers from Ruhr University Bochum in Germany.

The blood test uses a technology called immuno-infrared sensor to measure distribution of pathological and healthy structures of amyloid-beta, according to a study published in the Molecular Cell. The pathological amyloid-beta structure is rich in a sticky, sheet-like folding pattern that makes it prone to aggregation, while the healthy structure is not.

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I t has now been decades since stem cell technology emerged as the next great breakthrough in modern medicine, with the bold potential for one day curing everything from heart disease to cancer. Today, that optimism doesn’t appear to have diminished.

It’s easy to recall the excitement. In the late 1990s, when stem cell research was still relatively unexplored but gathering pace, the hope surrounding future uses for such treatments appeared near limitless. Once greater advances had been made, it was often argued, doctors could one day inject patients with cells that have the ability to transform into any other type of cell, making it possible to grow whole new organs. In theory, any damaged area…

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An early symptom is blurry vision in which straight lines appear distorted. That can progress to darkness, whiteouts, or blurry areas in the center of the visual field. The disease does not, by itself, lead to total blindness because peripheral vision remains unaffected. Although some therapies delay loss of central vision, no current treatments restore it completely.

“Macular degeneration therapies seem to be treating disease symptoms, rather than its cause,” Lin says. “We focused on the role of macrophages in regulating inflammation and the growth of abnormal blood vessels to see whether it may be possible one day to help people who don’t get much benefit from existing treatments and design therapies that may prevent progression to advanced forms of the disease.”

Virus delivers genes to fight vision loss.

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On April 2, 1845, Armand Hippolyte Louis Fizeau and Jean Bernard Léon Foucault manage to make the very first photography of the Sun. Thereby, they both initiate astronomical photography.

From a previous blog post you may remember Léon Foucault’s Pendulum.[4] The instrument was used to proof Earth’s rotation in the 1850s and counts to one of Foucault’s biggest scientific achievements. But let’s start a little bit earlier. Leon Foucault was born on September 18, 1819 as the son of a publisher in Paris. After an education received chiefly at home, he studied medicine, which he abandoned in favour of physics due to a fear of blood.

Meanwhile, astronomical photography started to establish slowly. There were not many experts in the field back then, since the very long exposures needed to capture relatively faint astronomical objects and many technological problems had to be overcome. Completely new telescopes had to be developed that were rigid enough in order to not lose the focus during exposure time. Also the telescopes had to be attached to a rotating mount that would move at a constant rate very accurately. Next to the telescope building itself, the technology of photography needed improvement as well. The daguerreotype was just introduced in 1839 and came into a very widespread use. However, for astronomical photography, the process was too slow and was only able to record very bright objects. Also, the exposure time was very limited using this method due to the wet plate collodion process.

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