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When measuring with light, the lateral extent of the structures that can be resolved by an optical imaging system is fundamentally diffraction limited. Overcoming this limitation is a topic of great interest in recent research, and several approaches have been published in this area.

In a recent study published in the Journal of Optical Microsystems, a team of researchers from the University of Kassel in Germany present an approach that uses microspheres placed directly on the surface of the object to extend the limits of interferometric topography measurements for optical of small structures.

Imaging below the resolution limit is often achieved with systems that use probe labeling, such as , which requires preparation of the sample. Other systems, such as atomic force microscopes, can provide 20 times better lateral resolution than diffraction-limited optical systems. However, they rely on tactile measurement principles that may be unsuitable for certain applications, especially in bio-imaging. Therefore, microsphere assistance can provide a solution for fast and label-free imaging below the diffraction limit.

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In 1961 astronomers discovered a powerful x-ray source coming from the constellation Cygnus. Not knowing what it was, they named the source Cygnus X-1. It’s one of the strongest x-ray sources in the sky, and we now know it is powered by a stellar-mass black hole. Since it is only about 7,000 light-years away, it also gives astronomers an excellent view of how stellar-mass black holes behave. Even after six decades of study, it continues to teach us a few things, as a recent study in Science shows.

Cygnus X-1 is actually a binary system. The black hole itself is a 21 solar-mass stellar remnant, and it orbits a 41 solar-mass companion star. It’s a powerful x-ray source because material from the star is captured into an accretion disk of the black hole, which superheats the material and generates jets of plasma that flow away from the black hole. This is a common situation for black holes, but astronomers still don’t understand all the details of how this type of structure evolves.

For this study, the team used data from the Imaging X-Ray Polarimetry Explorer (IXPE), which can capture not just x-rays but also their polarization. When they combined this data with other observations of Cygnus X-1, they found the x-rays are emitted not from the regions along the jets, but from a 2,000 km region perpendicular to the jets. In other words, the accretion disk itself is the primary x-ray source. This supports the model where the innermost region of the accretion disk is what powers a black hole’s jets.

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When you hit your finger with a hammer, you feel the pain immediately. And you react immediately.

But what if the pain comes 20 minutes after the hit? By then, the injury might be harder to heal.

Scientists and engineers at Rice University say the same is true for the environment. If a in a river goes unnoticed for 20 minutes, it might be too late to remediate.

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Scientists have discovered the cause of a rare condition within a part of the genome that has been largely unexplored in medical genetics. A team at the University of Exeter has found genetic changes in a region that controls the activity of the genome, turning on or off genes, and in doing so they have found a key that could unlock other causes of rare conditions.

The finding, published in Nature Genetics, is a very rare case of a cause of disease that only results from changes outside the exome, the region of the genome that codes for genes. It is also the first time that changes have been shown to affect a gene—known as HK1—that does not normally have a role in the relevant body tissue—in this case, the pancreas.

Until now, scientists have typically sequenced the part of the genome that describes the genetic code of all genes in individuals with a . They do this looking for variants in the DNA that affects a protein known to have an important role in the disease-relevant organ. A good example is observed in , where genetic variants disrupt the function of the pancreatic protein insulin, causing high blood sugar levels.

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You can imagine starting at the beginning, evolving the Universe forward according to the laws of physics, and measuring those earliest signals and their imprints on the Universe to determine how it has expanded over time. Alternatively, you can imagine starting here and now, looking out at the distant objects as we see them receding from us, and then drawing conclusions as to how the Universe has expanded from that.

Both of these methods rely on the same laws of physics, the same underlying theory of gravity, the same cosmic ingredients, and even the same equations as one another. And yet, when we actually perform our observations and make those critical measurements, we get two completely different answers that don’t agree with one another. This is, in many ways, the most pressing cosmic conundrum of our time. But there’s still a possibility that no one is mistaken and everyone is doing the science right. The entire controversy over the expanding Universe could go away if just one new thing is true: if there was some form of “early dark energy” in the Universe. Here’s why so many people are compelled by the idea.

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A team of engineers has developed a new type of camera that can detect radiation in terahertz (THz) wavelengths. This new imaging system can see through certain materials in high detail, which could make it useful for security scanners and other sensors.

Terahertz radiation is that which has wavelengths between microwaves and visible light, and these frequencies show promise in a new class of imaging systems. They can penetrate many materials and capture new levels of detail, and importantly the radiation is non-ionizing, meaning it’s safer than X-rays when used on humans.

The problem is that detectors that pick up THz wavelengths can be bulky, slow, expensive, difficult to run under practical conditions, or some combination of these. But in a new study, researchers at MIT, Samsung and the University of Minnesota have developed a system that can detect THz pulses quickly, precisely and at regular room temperature and pressure.

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