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When developers deliver software to their clients, they often also provide what is known as a ‘test suite.’ A test suite is a tool that allows users to test software, unveil any bugs it might have and give developers a chance to fix these bugs or other potential issues.

In addition to evaluating , therefore, developers also need to ascertain the efficacy of a suite in identifying bugs and errors. One way to run test suite evaluations is via , a technique that generates several ‘mutants’ of a program by slightly modifying its original code. While mutation testing tools have proved to be incredibly helpful, most of them cannot be applied to software that is only available in binary code (a way of representing texts or instructions for computers using two symbols, generally ‘0’ and ‘1’).

Researchers at Arizona State University, Worcester Polytechnic Institute and the University of Minnesota have recently developed SN4KE, a framework that can be used to carry out mutation analyses at a binary level. This framework, presented at the Binary Analysis Research (BAR) NDSS symposium ‘21 in February, is a new tool to efficiently test suites for software based on binary codes.

A new type of supply chain attack unveiled last month is targeting more and more companies, with new rounds this week taking aim at Microsoft, Amazon, Slack, Lyft, Zillow, and an unknown number of others. In weeks past, Apple, Microsoft, Tesla, and 32 other companies were targeted by a similar attack that allowed a security researcher to execute unauthorized code inside their networks.

The latest attack against Microsoft was also carried out as a proof-of-concept by a researcher. Attacks targeting Amazon, Slack, Lyft, and Zillow, by contrast, were malicious, but it’s not clear if they succeeded in executing the malware inside their networks. The npm and PyPi open source code repositories, meanwhile, have been flooded with more than 5000 proof-of-concept packages, according to Sonatype, a firm that helps customers secure the applications they develop.

“Given the daily volume of suspicious npm packages being picked up by Sonatype’s automated malware detection systems, we only expect this trend to increase, with adversaries abusing dependency confusion to conduct even more sinister activities,” Sonatype researcher Ax Sharma wrote earlier this week.

Materials capable of performing complex functions in response to changes in the environment could form the basis for exciting new technologies. Think of a capsule implanted in your body that automatically releases antibodies in response to a virus, a surface that releases an antibacterial agent when exposed to dangerous bacteria, a material that adapts its shape when it needs to sustain a particular weight, or clothing that senses and captures toxic contaminants from the air.

Scientists and engineers have already taken the first step toward these types of autonomous materials by developing “active” materials that have the ability to move on their own. Now, researchers at the University of Chicago have taken the next step by showing that the movement in one such active material—liquid crystals—can be harnessed and directed.

This proof-of-concept research, published on February 182021, in the journal Nature Materials, is the result of three years of collaborative work by the groups of Juan de Pablo, Liew Family Professor of Molecular Engineering, and Margaret Gardel, Horace B. Horton Professor of Physics and Molecular Engineering, along with Vincenzo Vitelli, professor of physics, and Aaron Dinner, professor of chemistry.

Envisioning an animal-free drug supply, scientists have — for the first time — reprogrammed a common bacterium to make a designer polysaccharide molecule used in pharmaceuticals and nutraceuticals. Published on March 22021, in Nature Communications, the researchers modified E. coli to produce chondroitin sulfate, a drug best known as a dietary supplement to treat arthritis that is currently sourced from cow trachea.

Genetically engineered E. coli is used to make a long list of medicinal proteins, but it took years to coax the bacteria into producing even the simplest in this class of linked sugar molecules — called sulfated glycosaminoglycans — that are often used as drugs and nutraceuticals…

“It’s a challenge to engineer E. coli to produce these molecules, and we had to make many changes and balance those changes so that the bacteria will grow well,” said Mattheos Koffas, lead researcher and a professor of chemical and biological engineering at Rensselaer Polytechnic Institute. “But this work shows that it is possible to produce these polysaccharides using E. coli in animal-free fashion, and the procedure can be extended to produce other sulfated glycosaminoglycans.”

With the help of the European Southern Observatory’s Very Large Telescope (ESO ’s VLT), astronomers have discovered and studied in detail the most distant source of radio emission known to date. The source is a “radio-loud” quasar — a bright object with powerful jets emitting at radio wavelengths — that is so far away its light has taken 13 billion years to reach us. The discovery could provide important clues to help astronomers understand the early Universe.

Quasars are very bright objects that lie at the center of some galaxies and are powered by supermassive black holes. As the black hole consumes the surrounding gas, energy is released, allowing astronomers to spot them even when they are very far away.

The newly discovered quasar, nicknamed P172+18, is so distant that light from it has traveled for about 13 billion years to reach us: we see it as it was when the Universe was just around 780 million years old. While more distant quasars have been discovered, this is the first time astronomers have been able to identify the telltale signatures of radio jets in a quasar this early on in the history of the Universe. Only about 10% of quasars — which astronomers classify as “radio-loud” — have jets, which shine brightly at radio frequencies.[1].

Columbia researchers engineer first technique to exploit the tunable symmetry of 2D materials for nonlinear optical applications, including laser, optical spectroscopy, imaging, and metrology systems, as well as next-generation optical quantum information processing and computing.

Nonlinear optics, a study of how light interacts with matter, is critical to many photonic applications, from the green laser pointers we’re all familiar with to intense broadband (white) light sources for quantum photonics that enable optical quantum computing, super-resolution imaging, optical sensing and ranging, and more. Through nonlinear optics, researchers are discovering new ways to use light, from getting a closer look at ultrafast processes in physics, biology, and chemistry to enhancing communication and navigation, solar energy harvesting, medical testing, and cybersecurity.

Columbia Engineering researchers report that they developed a new, efficient way to modulate and enhance an important type of nonlinear optical process: optical second harmonic generation — where two input photons are combined in the material to produce one photon with twice the energy — from hexagonal boron nitride through micromechanical rotation and multilayer stacking. The study was published online on March 32021, by Science Advances.

Human and non-human animal behavior is highly malleable and adapts successfully to internal and external demands. Such behavioral success stands in striking contrast to the apparent instability in neural activity (i.e., variability) from which it arises. Here, we summon the considerable evidence across scales, species, and imaging modalities that neural variability represents a key, undervalued dimension for understanding brain-behavior relationships at inter-and intra-individual levels. We believe that only by incorporating a specific focus on variability will the neural foundation of behavior be comprehensively understood.