Lifeboat Foundation

SMU and the University of Rhode Island have patented an inexpensive, easy-to-use method to create solid-state nanopores (SSNs), while also making it possible to self-clean blocked nanopores.

The technique called chemically-tuned controlled dielectric breakdown (CT-CDB) addresses two key problems that have kept solid-state nanopores – which are too tiny for the human eye to see – from being used more often to build biosensors that can measure biological and chemical reactions of a given sample.

Biosensors have widespread medical applications, enabling rapid, early and effective disease diagnosis and monitoring.

Exoplanets are common in our galaxy, and some even orbit in the so-called habitable zone of their star. NASA’s James Webb Space Telescope has been busy observing a few of these small, potentially habitable planets, and astronomers are now hard at work analyzing Webb data. We invite Drs. Knicole Colón and Christopher Stark, two Webb project scientists at NASA’s Goddard Space Flight Center, to tell us more about the challenges in studying these other worlds:

A potentially habitable planet is often defined as a planet similar in size to Earth that orbits in the ‘habitable zone’ of its star, a location where the planet could have a temperature where liquid water could exist on its surface. We currently know of around 30 planets that may be small, rocky planets like Earth and that orbit in the habitable zone. However, there is no guarantee that a planet that orbits in the habitable zone actually is habitable (it could support life), let alone inhabited (it currently supports life). At the time of writing, there is only one known habitable and inhabited planet—Earth.

The potentially habitable worlds Webb is observing are all transiting exoplanets, meaning their orbits are nearly edge-on so that they pass in front of their host stars. Webb takes advantage of this orientation to perform transmission spectroscopy when the planet passes in front of its star. This orientation allows us to examine the starlight filtered through the atmospheres of planets to learn about their chemical compositions.

Scientists at Duke-NUS Medical School have identified how the first domino falls after a person encounters an allergen, such as peanuts, shellfish, pollen or dustmites. Their discovery, published in the April issue of Nature Immunology, could herald the development of drugs to prevent these severe reactions.

It is well established that when mast cells, a type of immune cell, mistake a harmless substance, such as peanuts or dust mites, as a threat, they release an immediate first wave of bioactive chemicals against the perceived threat. When mast cells, which reside under the skin, around blood vessels and in the linings of the airways and the gastrointestinal tract, simultaneously release their pre-stored load of bioactive chemicals into the blood, instant and systemic shock can result, which can be lethal without quick intervention.

More than 10 per cent of the global population suffers from food allergies, according to the World Health Organisation (WHO). As allergy rates continue to climb, so does the incidence of food-triggered anaphylaxis and asthma worldwide. In Singapore, asthma affects one in five children while food allergies are already the leading cause of anaphylactic shock.

Recent research on isoporous membranes, which feature uniformly sized pores, show potential for improving the precision and efficiency of industrial separation processes by allowing solutes multiple attempts to pass through the pores.

Imagine a close basketball game that comes down to the final shot. The probability of the ball going through the hoop might be fairly low, but it would dramatically increase if the player were afforded the opportunity to shoot it over and over.

A similar idea is at play in the scientific field of membrane separations, a key process central to industries that include everything from biotechnology to petrochemicals to water treatment to food and beverage.

Giorgia Marucci of HORIBA explains how Jennifer Doudna, Emmanuelle Charpentier and their research teams revolutionized genetic engineering with their CRISPR-Cas9 discovery. Their groundbreaking approach to DNA editing elevated these two scientists to Nobel Laureate status when they received the Nobel Prize in Chemistry in 2020.

Read more about this story at: https://www.horiba.com/int/scientific…

Continue reading “CRISPR/Cas9: Big Discovery in Gene Editing” »

Growth of data eases the way to access the world but requires increasing amounts of energy to store and process. Neuromorphic electronics has emerged in the last decade, inspired by biological neurons and synapses, with in-memory computing ability, extenuating the ‘von Neumann bottleneck’ between the memory and processor and offering a promising solution to reduce the efforts both in data storage and processing, thanks to their multi-bit non-volatility, biology-emulated characteristics, and silicon compatibility. This work reviews the recent advances in emerging memristive devices for artificial neuron and synapse applications, including memory and data-processing ability: the physics and characteristics are discussed first, i.e., valence changing, electrochemical metallization, phase changing, interfaced-controlling, charge-trapping, ferroelectric tunnelling, and spin-transfer torquing. Next, we propose a universal benchmark for the artificial synapse and neuron devices on spiking energy consumption, standby power consumption, and spike timing. Based on the benchmark, we address the challenges, suggest the guidelines for intra-device and inter-device design, and provide an outlook for the neuromorphic applications of resistive switching-based artificial neuron and synapse devices.

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Memristor synapses based on green and pollution-free organic materials are expected to facilitate biorealistic neuromorphic computing and to be an important step toward the next generation of green electronics. Metalloporphyrin is an organic compound that widely exists in nature with good biocompatibility and stable chemical properties, and has already been used to fabricate memristors. However, the application of metalloporphyrin-based memristors as synaptic devices still faces challenges, such as realizing a high switching ratio, low power consumption, and bidirectional conductance modulation. We developed a memristor that improves the resistive switching (RS) characteristics of Zn(II)meso-tetra(4-carboxyphenyl) porphine (ZnTCPP) by combining it with deoxyribonucleic acid (DNA) in a composite film. The as-fabricated ZnTCPP-DNA-based device showed excellent RS memory characteristics with a sufficiently high switching ratio of up to ∼10⁴, super low power consumption of ∼39.56 nW, good cycling stability, and data retention capability. Moreover, bidirectional conductance modulation of the ZnTCPP-DNA-based device can be controlled by modulating the amplitudes, durations, and intervals of positive and negative pulses. The ZnTCPP-DNA-based device was used to successfully simulate a series of synaptic functions including long-term potentiation, long-term depression, spike time-dependent plasticity, paired-pulse facilitation, excitatory postsynaptic current, and human learning behavior, which demonstrates its potential applicability to neuromorphic devices. A two-layer artificial neural network was used to demonstrate the digit recognition ability of the ZnTCPP-DNA-based device, which reached 97.22% after 100 training iterations. These results create a new avenue for the research and development of green electronics and have major implications for green low-power neuromorphic computing in the future.

Keywords: artificial synapses; memristors; neuromorphic computing; porphyrin−DNA composite films; superlow power consumption.

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More than 3.5 billion years ago, life on Earth emerged from chemical reactions. Nature invented RNA, proteins, and DNA, the core molecules of life, and created the ribosome, a molecular factory that builds proteins from instructions in the genome.

Proteins are wondrous dynamic molecules with incredible functions—from molecular engines that power motion, to photosynthetic machines that capture light and convert it to energy, scaffolding that builds the internal skeletons of cells, complex sensors that interact with the environment, and information processing systems that run the programs and operating system of life. Proteins underlie disease and health, and many life-saving medicines are proteins.

Biology is the most advanced technology that has ever been created, far beyond anything that people have engineered. The ribosome is programmable—it takes the codes of proteins in the form of RNA and builds them up from scratch—fabrication at the atomic scale. Every cell in every organism on earth has thousands to millions of these molecular factories. But even the most sophisticated computational tools created to date barely scratch the surface: biology is written in a language we don’t yet understand.

After its “birth” in the Big Bang, the universe consisted mainly of hydrogen and a few helium atoms. These are the lightest elements in the periodic table. More-or-less all elements heavier than helium were produced in the 13.8 billion years between the Big Bang and the present day.

Stars have produced many of these heavier elements through the process of nuclear fusion. However, this only makes elements as heavy as iron. The creation of any heavier elements would consume energy instead of releasing it.

In order to explain the presence of these heavier elements today, it’s necessary to find phenomena that can produce them. One type of event that fits the bill is a gamma-ray burst (GRB)—the most powerful class of explosion in the universe. These can erupt with a quintillion (10 followed by 18 zeros) times the luminosity of our sun, and are thought to be caused by several types of event.