A teen’s nutrient-poor diet led to irreversible vision problems.
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Proton pump rhodopsins for optogenetic manipulation of biological activities and beyond
(H2O), the principal component of living organisms including humans, dissociates into H+ and OH-in aqueous environments, and the resulting H+ concentration determines both cellular pH and the proton motive force (PMF) across cellular membranes. These physicochemical parameters are fundamental regulators of a wide range of biological processes. Optogenetics enables the manipulation of biological and cellular functions using light, typically through the ectopic expression of microbial rhodopsins as photoreceptive proteins in target cells or organs.
Predicting Risk of Cognitive Impairment With Alzheimer Disease Blood Biomarkers
Alzheimer disease is the most common cause of dementia in older individuals. Cerebrospinal fluid biomarkers and amyloid positron emission tomography (PET) can accurately detect Alzheimer disease brain pathology, but the perceived risks, costs, and limited availability have contributed to low rates of biomarker testing in the clinic.1 With recent approvals of disease-modifying, amyloid-targeting therapies, incorporation of biomarkers into clinical practice has become more important for medical decision-making. Fortunately, blood-based biomarkers of Alzheimer disease pathology have advanced rapidly in recent years and are now increasingly used in research, clinical trials, and clinical practice.2 Blood-based biomarkers are highly scalable and promise to improve accurate diagnosis of Alzheimer disease, with the potential for much greater reach than cerebrospinal fluid or PET tests.2 Among the blood-based biomarkers, plasma phosphorylated tau 217 (p-tau217) has demonstrated the highest accuracy in detecting amyloid pathology and also reflects tau pathology to some degree.3-5
Although Alzheimer disease biomarkers are increasingly being incorporated into clinical practice in patients with mild cognitive impairment or mild dementia (the populations for which amyloid-targeting therapies have demonstrated clinical benefit), these measures are also sensitive to early biological changes associated with Alzheimer disease that precede the onset of clinical symptoms.6 Indeed, these biological changes are thought to begin a decade or more prior to the onset of cognitive decline, during an asymptomatic phase of disease that has often been referred to as preclinical Alzheimer disease.7 Importantly, current Alzheimer’s Association clinical practice guidelines limit testing for Alzheimer disease pathology using blood-based and other Alzheimer disease biomarkers to individuals with objective cognitive impairment undergoing diagnostic evaluation in specialty care; clinical testing of cognitively unimpaired older adults is not recommended at this time.2
However, in the research setting, unimpaired individuals with biomarker evidence of Alzheimer disease pathology have been the focus of numerous natural history studies and, more recently, secondary prevention trials testing whether targeting pathology can forestall the onset of cognitive impairment.8 Studies have demonstrated that higher plasma p-tau217 levels in cognitively unimpaired individuals are associated with higher risk for future cognitive decline and progression to mild cognitive impairment or dementia.9-11 The ability of blood-based biomarkers to detect early Alzheimer disease pathology in cognitively unimpaired individuals with high sensitivity has already been translated to clinical trials of amyloid-targeting therapies. The TRAILBLAZER-ALZ 3 clinical trial enrolled cognitively unimpaired individuals with elevated p-tau217 and is evaluating whether donanemab reduces progression to cognitive impairment.
Plasma agriculture makes strides toward super-seeding conventional methods
Occasionally, the sun unleashes powerful flares and coronal mass ejections, which hurl plasma and energetic particles into space. On the infant Earth, this solar activity drove cascades of atmospheric chemical reactions that may have helped form the building blocks of life. More recently, scientists have discovered that applying plasma to seeds in a controlled way can trigger similar activity, making them faster-growing and more resilient. Researchers at Nagoya University and Kyushu University in Japan have compiled a comprehensive review of this new field—termed “plasma agriculture”—as a potential sustainable solution to address global food shortages.
The word plasma brings to mind a hot, ionized inferno that makes up the fourth state of matter. But the plasma used here is different. By applying high voltage to air or any gas, electrons are stripped from a tiny fraction of its molecules and gain very high energies. These electrons zipping around can effectively mimic the behavior of plasma even though the bulk of the gas remains at room temperature.
This low-temperature plasma can be applied directly to seeds without burning them. Excessive use of chemicals and genetic modification of plants cause concern for many people. Instead, plasma agriculture can offer similarly high crop yields without invasive intervention.
Doughnut‑shaped topology reveals new way to classify knitting, crochet and other textiles
Fabrics are made by repeatedly intertwining yarns into characteristic patterns. Many of their properties, such as stretchiness, arise not only from the material itself but also from how the yarns are arranged and entangled. Such properties illustrate how topology—the underlying patterns of connectivity and entanglement within a structure—can shape a material’s overall behavior. Understanding these relationships could help researchers design materials with tailored properties through the design of their topology.
A research team led by Dr. Daisuke S. Shimamoto, a senior researcher at the Research Organization of Science and Technology, Ritsumeikan University, Japan, along with Dr. Keiko Shimamoto, an independent researcher from Tokyo, Japan, Dr. Sonia Mahmoudi from Tohoku University, and Dr. Samuel Poincloux from Aoyama Gakuin University, has developed a mathematical framework based on knot theory for characterizing knittability and classifying periodic textile structures based on how defects spread through them. Their findings were published in Physical Review X on July 14, 2026.
Alien world chemistry found inside meteorite that struck New Jersey home
On July 16, 2024, a daytime meteor shook New York City with a sonic boom as it passed just south of the Statue of Liberty. Now, an international team of researchers reports in the journal Science Advances that a short time later, a meteorite weighing more than 2 pounds crashed through the roof of a house in the town of Hillsborough, New Jersey.
“A forensic study of the fragments revealed that they contained preserved bits from near the surface of a primitive asteroid, where it experienced concentrated salty fluids—a process not previously known from this type of protoplanet world,” said lead author and meteor astronomer Peter Jenniskens of the SETI Institute and NASA’s Ames Research Center in California’s Silicon Valley.
On that day, a rock the size of a heavy airline bag entered Earth’s atmosphere at a speed of 32,000 miles/h (14.4 kilometers per second). Sixty observers from New York, New Jersey, Connecticut, Rhode Island and Pennsylvania reported seeing the meteor to the American Meteor Society, while 16 in New York and New Jersey felt the shock wave.
A new stellar census strengthens the case for a 13.8-billion-year-old universe
Astronomers have used the ages of more than 155,000 stars in the Milky Way to independently estimate the age of the universe, and their findings may be good news for the standard cosmological model. The new research was reported in a paper submitted to the arXiv preprint server on July 1.
The age of the universe is tied to a discrepancy known as the Hubble tension. There are two main ways to measure how fast the universe is expanding, known as the Hubble constant. The first uses the cosmic microwave background (CMB), the “afterglow” of the Big Bang, and gives a certain value. The other uses local measurements in our cosmic neighborhood, including Cepheid stars and supernovae, and gives a noticeably higher value.
The two figures disagree by about 9%—a mismatch known as the Hubble tension.
Faster quantum computers can learn from their own mistakes
Quantum computers promise to solve problems that would take even the fastest conventional supercomputers a vast amount of time, but the quantum information they store and process is extremely sensitive to even tiny disturbances from their surroundings. To keep these systems operating reliably, they need to be constantly recalibrated—interrupting their calculations in the process.
In a new experiment published in Nature, researchers led by Volodymyr Sivak at Google Quantum AI developed a machine-learning approach that continuously adjusts a quantum computer as it works. Their approach could allow quantum calculations to run far longer without costly interruptions.