Lifeboat Foundation

Recently, a research team led by Prof. Guo Guangcan from the University of Science and Technology of China (USTC) constructed a non-Hermiticity (NH) synthetic orbital angular momentum (OAM) dimension in a degenerate optical cavity and observed the exceptional points (EPs). This study was published in Science Advances.

In topological physics, the NH systems depict open systems with complex energy spectra. Exceptional points are one of the unique features of NH systems. To study EPs, the team had constructed synthetic one-dimensional lattices and established topological simulation platform in a degenerate optical cavity. Based on this platform, an additional pseudomomentum was introduced as a parameter to construct the Dirac point in the two-dimensional momentum space. A pair of EPs can be obtained by introducing non-Hermitian perturbation around the Dirac point.

The detection of complex energy spectra in NH systems can be troublesome for traditional means. The research group developed a method which is referred to as wave front angle–resolved band structure spectroscopy to investigate complex energy spectra based on synthetic OAM. Using this method, the team not only detected EPs in momentum space, but also the key features of EPs like bulk Fermi arcs, parity-time symmetry-breaking transition, energy swapping and half-integer band windings.

Rodents are considered one of the animal pests with the greatest impact on agricultural production and public health, especially the brown or Norway rat (Rattus norvegicus), the black or roof rat (Rattus rattus) and the house mouse (Mus musculus). Its control is an increasing problem worldwide. The intensification of agricultural production methods as well as the increase in merchandise transport to sustain growing populations is leading to an increase in waste production causing the growth of these rodent populations. The estimated losses in crop production caused by rodents range from between 5% and 90% (Stenseth et al., 2003) and this can cause problems in food security during harvesting (Belmain et al., 2015). Other negative impacts result from some rodent species living very close to human environments that can have a direct influence not only on human health through potential transmission of gastroenteric diseases and zoonosis to householders but also on domestic livestock. Therefore, rodent pest control is crucial and nowadays, the only effective control method available is the use of anticoagulant rodenticides (ARs).

ARs are so named because they interfere with the blood coagulation processes. The processes of activating various coagulation factors depends on the amount of vitamin K in its reduced form that exists in the organism. ARs inhibit the enzyme vitamin K 2,3-epoxide reductase (VKORC1) that is responsible for reducing vitamin K and maintaining the balance between its oxidized and reduced forms. The inhibition of VKORC1 prevents the activation of the coagulation factors resulting in animal death by internal bleeding. However, the intensive use of ARs can cause rodents to lose their susceptibility and become resistant to them. Genetic resistances to ARs are mainly associated with mutations or single nucleotide polymorphisms (SNPs) in the gene that codes for VKORC1 (vkorc1), causing amino acid substitutions in the VKORC1 protein ( Pelz et al., 2005 ). There are studies on this topic in several countries of central and northern Europe detecting rodent populations resistant to AR. Currently, there are at least 13 mutations mainly located in the exon 3 of the vkorc1 gene described in various countries of the European Union that confer resistance to specific ARs ( Berny et al., 2014 ; Goulois et al., 2017 ). In Eastern and Southern European countries, the information on the incidence of resistances to rodenticides is scarce, and it is becoming increasingly important to generate information on this subject ( Berny et al., 2014). In Spain, a mice population at the coastal countryside showing an adaptive introgression between house mouse and Algerian mouse that confers anticoagulant resistance has been described ( Song et al., 2011 ). While recently, four VKORC1 mutations in black rat were found in Toledo, Segovia and Zaragoza ( Goulois et al., 2016 ; Damin-Pernik et al., 2022 ). Any increase in resistant in rodent populations would lead to pest control issues that may causing serious agricultural, farming and public health problems.

Scientific advances have revolutionized the study of anticoagulant resistances in terms of understanding their genetic basis, physiological mechanisms and geographical distribution. The techniques based on the extraction and partial sequencing of genomic DNA allow a fast and precise monitoring of possible genetic resistances. Most of these tests involve laboratory studies using live rodents or blood samples taken from animals in the field. However, the improvement of DNA extraction techniques now allows the analysis of faecal samples (stool), increasing the number of samples that can be taken without the need for sampling by trapping or the management of dead animals (Meerburg et al., 2014). The importance of initial detection of genetic resistances due to mutations is crucial. The hypothesis of work, presenting it as a null hypothesis, is that there will be no rodent mutations in the vkorc1 gene in Spain.

The physicists at the University of Bonn have experimentally demonstrated that a crucial theorem in statistical physics is applicable to Bose-Einstein condensates. This discovery enables the measurement of specific properties of these quantum “superparticles,” providing a means of deducing system characteristics that would otherwise be challenging to observe. The findings of this study have been published in the journal Physical Review Letters.

Suppose in front of you there is a container filled with an unknown liquid. Your goal is to find out by how much the particles in it (atoms or molecules) move back and forth randomly due to their thermal energy. However, you do not have a microscope with which you could visualize these position fluctuations known as “Brownian motion”.

It turns out you do not need that at all: You can also simply tie an object to a string and pull it through the liquid. The more force you have to apply, the more viscous your liquid. And the more viscous it is, the lesser the particles in the liquid change their position on average. The viscosity at a given temperature can therefore be used to predict the extent of the fluctuations.

From regulators to researchers and most industries in between, all eyes are on PFAS, per-and polyfluoroalkyl substances, are a class of highly fluorinated human-made compounds that have been used for decades in everything from nonstick cookware and personal care products to fire-fighting foams and school uniforms. Their commonality and extreme resistance to environmental degradation has made them ubiquitous in ground water, soil, and worst of all humans. Linked to a slew of health risks including liver toxicity, bladder cancer, and decreased immune response to vaccinations, exposure to PFAS is concerning. So, how can we eliminate these “forever chemicals?”

Historically, PFAS substances have only been characterized in water and soil, but the emission of these compounds during chemical manufacturing, use, and disposal results in their emission into the air. Ryan Sullivan, Professor of Mechanical Engineering and Chemistry at Carnegie Mellon University, has been developing new methods to measure PFAS in both the atmosphere and in aerosol particles to answer outstanding questions regarding PFAS atmospheric components that lead to human exposure. His group is also developing new approaches to destroy forever molecules that are not removed by conventional water treatment plants.

The research is published in the journal Environmental Science: Processes & Impacts.

Most existing COVID-19 tests “rely on the same principle, which is that you have accumulated a detectable amount of viral material, for example, in your nose,” says study lead author Frank Zhang, who worked on the project as a Flatiron research fellow at the Flatiron Institute’s Center for Computational Biology (CCB) in New York City. “That poses a challenge when it’s early in the infection time window and you haven’t accumulated a lot of viral material, or you’re asymptomatic.”

The new technique is instead based on how our bodies mount an immune response when invaded by SARS-CoV-2, the virus that causes COVID-19. When the assault starts, specific genes turn on. Segments of those genes produce mRNA molecules that guide the building of proteins. The particular blend of those mRNA molecules changes the types of proteins produced, including proteins involved in virus-fighting functions. The new method can confidently identify when the body is mounting an immune response to the COVID-19 virus by measuring the relative abundance of the various mRNA molecules. The new study is the first to use such an approach to diagnose an infectious disease.

We often think that our world is an infinite realm comprising great plains, jungles and oceans, teeming with wild animals featured in memorable nature shows like the BBC’s Planet Earth. But the first global census of wild mammal biomass, conducted by Weizmann Institute of Science researchers and reported today in PNAS, reveals the extent to which our natural world—along with its most iconic animals—is a vanishing one.

The new report shows that the biomass of wild mammals on land and at sea is dwarfed by the combined weight of cattle, pigs, sheep and other domesticated mammals. A team headed by Prof. Ron Milo found that the biomass of livestock has reached about 630 million tons—30 times the weight of all wild terrestrial mammals (approximately 20 million tons) and 15 times that of wild marine mammals (40 million tons).

An earlier, widely-discussed study in Nature by researchers in Milo’s lab in Weizmann’s Plant and Environmental Sciences Department showed that in 2020, the mass of human-made objects—anything from skyscrapers to newspapers—had surpassed the planet’s entire biomass, from redwood trees to honeybees. In the latest study, the researchers offer a new perspective on humanity’s rapidly increasing impact on our planet, seen in the ratio between humans and domesticated mammals, and wild mammals.

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In this paper, we demonstrate, in the context of Loop Quantum Gravity, the Quantum Holographic Principle, according to which the area of the boundary surface enclosing a region of space encodes a qubit per Planck unit. To this aim, we introduce fermion fields in the bulk, whose boundary surface is the two-dimensional sphere. The doubling of the fermionic degrees of freedom and the use of the Bogolyubov transformations lead to pairs of the spin network’s edges piercing the boundary surface with double punctures, giving rise to pixels of area encoding a qubit. The proof is also valid in the case of a fuzzy sphere.

It’s not “The Last of Us,” but it sure is weird. Here’s how mushrooms and fungi can be used to carry out problems computers typically solve.

Altman acknowledges that “our current progress could hit a wall.” I think this is important given the hype surrounding large language models (LLM). Constant progress in LLMs and other deep learning models has led some to believe that we’re on the path to creating AGI. But there are clear signs that LLMs alone cannot solve critical aspects of intelligence and can make fatal mistakes if entrusted with sensitive tasks.

A new blog post by Sam Altman explains OpenAI’s updated roadmap for artificial general intelligence. He answers some questions and leaves many others unanswered.