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The qualia problem of perception is simply pointing out that the way we perceive the world is in terms of subjective qualities rather than numerical quantities. For example, we perceive the color of light in the things we see rather than the frequency of light wave vibrations or wavelengths, just as we perceive the quality of the sounds we hear rather than the frequency of sound wave vibrations. Another example is emotional qualities, like the perception of pleasure and pain and the perception of other emotional qualities, like the emotional qualities that color the perception of the emotional body feelings we perceive with emotional expressions of fear and desire. There is no possible way to understand the perception of these emotional qualities, just as there is no way to understand the perception of the colors we see or the qualities of the sounds we hear, in terms of the neuronal firing rates of neurons in the brain or other nervous systems. The frequency of wave vibrations and the neuronal firing rates of neurons are both examples of quantities. The problem is we do not perceive things in terms of numerical quantities, but rather in terms of subjective qualities.

All our physical theories are formulated in terms of numerical quantities, not in terms of subjective qualities. For example, in ordinary quantum theory or in quantum field theory, we speak of the frequency of light wave vibrations or the wavelength of a light wave in terms of a quantum particle called the photon. A photon or light wave is characterized by the numerical quantities of frequency and wavelength. When we formulate the nature of a light wave or photon in quantum theory in terms of Maxwell’s equations for the electromagnetic field, we can only describe numerical quantities. In ordinary quantum theory and quantum field theory, the electromagnetic field is the quantum wave-function, ψ(x, t), that specifies the quantum probability that the point particle called the photon can be measured at a position x in space at a moment t in time. That quantum probability is specified in terms of the frequency and wavelength that characterizes the wave-function for the photon.

Neural data analysis algorithms capable of tracking neuronal signals from one-photon functional imaging data longitudinally and reliably are still lacking. Here authors developed CaliAli, a tool for extracting calcium signals across multiple days. Validated with optogenetic tagging, dual-color imaging, and place cell data, CaliAli demonstrated stable neuron tracking for up to 99 days.

Researchers have developed an extremely thin, flexible imager that could be useful for noninvasively acquiring images from inside the body. The new technology could one day enable early and precise disease detection, providing critical insights to guide timely and effective treatment.

“As opposed to existing prohibitively large endoscopes made of cameras and or bulky fiber optic bundles, our microimager is very compact,” said research team leader Maysam Chamanzar from Carnegie Mellon University. “Much thinner than a typical eyelash, our device is ideal for reaching deep regions of the body without causing significant damage to the tissue.”

In the journal Biomedical Optics Express, the researchers showed that the microimager, which is only 7 microns thick—a tenth of an eyelash diameter—and about 10 mm long, can be used in a for structural and functional imaging of brain activity. The width of the thin film imager can be customized based on the desired field of view and resolution.

Astrobee is a free-flying robotic system developed by NASA that is made up of three distinct cube-shaped robots. This system was originally designed to help astronauts who are working at the International Space Station (ISS) by automating some of their routine manual tasks.

While Astrobee could be highly valuable for astronauts, boosting the efficiency with which they complete day-to-day operations, its object manipulation capabilities are not yet optimal. Specifically, past experiments suggest that the robot struggles when handling deformable items, including bags that resemble some of those that it might be tasked to pick up on the ISS.

Researchers at Stanford University, University of Cambridge and NASA Ames recently developed Pyastrobee, a simulation environment and control stack to train Astrobee in Python, with a particular emphasis on the manipulation and transport of cargo.

Duke University Medical Center-led research has identified a human-specific DNA enhancer that regulates neural progenitor proliferation and cortical size. Small genetic changes in HARE5 amplify a key developmental pathway, resulting in increased cortical size and neuron number in experimental models. Findings have implications for understanding the genetic mechanisms underlying neurodevelopmental disorders.

Humans possess a significantly larger and more complex cerebral cortex compared to other species, contributing to advanced cognitive functions. Comparative genomics research has identified Human Accelerated Regions (HARs), segments of non-coding DNA with human-specific genetic changes. Many HARs are located near genes associated with and neural differentiation.

Because thousands of HARs have been identified and linked to brain-related genes, the next critical step is to investigate how these actively shape human brain features.

The study revealed genes and cellular pathways that haven’t been linked to Alzheimer’s before, including one involved in DNA repair. Identifying new drug targets is critical because many of the Alzheimer’s drugs that have been developed to this point haven’t been as successful as hoped.

Working with researchers at Harvard Medical School, the team used data from humans and to identify cellular pathways linked to neurodegeneration. This allowed them to identify additional pathways that may be contributing to the development of Alzheimer’s.

The Higgs boson, discovered at the Large Hadron Collider (LHC) in 2012, plays a central role in the Standard Model of particle physics, endowing elementary particles such as quarks with mass through its interactions. The Higgs boson’s interaction with the heaviest “third-generation” quarks—top and bottom quarks—has been observed and found to be in line with the Standard Model.

But probing its interactions with lighter “second-generation” quarks, such as the quark, and the lightest “first-generation” quarks—the up and down quarks that make up the building blocks of atomic nuclei—remains a formidable challenge, leaving unanswered the question of whether or not the Higgs boson is responsible for generating the masses of the quarks that make up ordinary matter.

Researchers study the Higgs boson’s interactions by looking at how the particle decays into—or is produced with—other particles in high-energy proton–proton collisions at the LHC.