The gene-editing technology has led to innovations in medicine, evolution and agriculture — and raised profound ethical questions about altering human DNA.
Category: food – Page 124
Some things that could make the world more efficient simply feel impossible to achieve — not like having to eat and sleep or not suffering through inflated grocery store prices.
Earlier this week, though, scientists at UC Riverside and the University of Delaware say they found a way to cross one of those seemingly impossible barriers when they convinced plants to grow in total darkness. A university press release says the team used a two-step process to convert carbon dioxide, electricity and water into acetate. Plants consumed the acetate and were able to grow in the dark.
The release said that combined with solar panels to generate electricity, this method of food production would be more than 18 times as effective as the natural process, which they claim uses only 1 percent of the energy found in sunlight alone. The team’s research was published Thursday in the journal Nature Food.
Materials scientists and bioengineers at the intersection of regenerative medicine and bioinspired materials seek to develop shape-programmable artificial muscles with self-sensing capabilities for applications in medicine. In a new report now published in Science Advances, Haoran Liu and a team of researchers in systems and communications engineering at the Frontier Institute of Science and Technology, Jiaotong University, China, were inspired by the coupled behavior of muscles, bones, and nerve systems of mammals and other living organisms to create a multifunctional artificial muscle in the lab. The construct contained polydopamine-coated liquid crystal elastomer (LCE) and low-melting point alloys (LMPA) in a concentric tube or rod. While the team adopted the outer liquid crystal-elastomer to mimic reversible contraction and recovery, they implemented the inner low-melting point alloy for deformation locking and to detect resistance mechanics, much like bone and nerve functions, respectively. The artificial muscle demonstrated a range of performances, including regulated bending and deformation to support heavy objects, and is a direct and effective approach to the design of biomimetic soft devices.
Soft robotics inspired by the skeleton–muscle–nerve system
Scientists aim to implement biocompatibility between soft robotic elements and human beings for assisted movement and high load-bearing capacity; however, such efforts are challenging. Most traditional robots are still in use in industrial, agricultural and aerospace settings for high-precision sensor-based, load-bearing applications. Several functional soft robots contrastingly depend on materials to improve the security of human-machine interactions. Soft robots are therefore complementary to hard robots and have tremendous potential for applications. Biomimetic constructs have also provided alternative inspiration to emulate the skeleton-muscle-nerve system to facilitate agile movement and quick reaction or thinking, with a unique body shape to fit tasks and perform diverse physiological functions. In this work, Liu et al were inspired by the fascinating idea of biomimicry to develop multifunctional artificial muscles for smart applications.
Merging COVID-19 + MonkeyFox +????
Martin Chartrand https://www.nbcnews.com/…/who-monkeypox-public-health…
Scientists have recently reported discovering what they believe is the most massive black hole ever discovered in the early Universe.
It is 34 billion times the mass of our Sun, and it eats the equivalent of one Sun every day.
The need to find alternative sources for fertilizer have become urgent as chemical fertilizer shortages from the Ukrainian war threaten countries globally.
A Chinese military analyst suggested countermeasures for the Starlink satellite system developed by Musk’s SpaceX – including ways to hack or destroy the service.
Neocortex saves energy
Posted in food, neuroscience
Despite constituting less than 2% of the body’s mass, the human brain consumes approximately 20% of total caloric intake, with 50% of the energy being used by cortex (Herculano-Houzel, 2011). The majority of this energy is spent by neurons to reverse the ion fluxes associated with electrical signaling via Na+/K+ ATPase (Attwell and Laughlin, 2001; Harris et al., 2012). Excitatory synaptic currents and action potentials are particularly costly in this regard, accounting for approximately 57% and 23% of the energy budget for electrical signaling in gray matter, respectively (Harris et al., 2012; Sengupta et al., 2010). Given this cost, and the scarcity of resources, the brain is thought to have evolved an energy-efficient coding strategy that maximizes information transmission per unit energy (i.e., ATP) (Barlow, 2012; Levy and Baxter, 1996). This strategy accounts for a number of cellular features, including the low mean firing rate of neurons and the high failure rate of synaptic transmission, as well as higher order features, such as the structure of neuronal receptive fields (Albert et al., 2008; Attwell and Laughlin, 2001; Harris et al., 2015; Levy and Baxter, 1996; Olshausen and Field, 1997; Sterling and Laughlin, 2015). Scarcity of food, therefore, appears to have strongly sculpted information coding in the brain throughout evolution.
Energy intake is not fixed but can vary substantially across individuals, environments, and time (Hladik, 1988; Knott, 1998). Given that the brain is energy limited, one hypothesis is that in times of food scarcity, neuronal networks should save energy by reducing information processing. There is some evidence to suggest that this is the case in invertebrates (Kauffman et al., 2010; Longden et al., 2014; Plaçais et al., 2017; Placais and Preat, 2013). In Drosophila 0, food deprivation inactivates neural pathways required for long-term memory to preserve energy (Plaçais et al., 2017; Placais and Preat, 2013). Experimental re-activation of these pathways restores memory formation but significantly reduces survival rates (Placais and Preat, 2013). Similar memory impairments are seen with reduced food intake in C. elegans (Kauffman et al., 2010). Moreover, in blowfly, food deprivation reduces visual interneuron responses during locomotion, consistent with energy savings (Longden et al., 2014). However, it remains unclear whether and how the mammalian brain, and cortical networks in particular, regulate information processing and energy use in times of food scarcity.
Here we used the mouse primary visual cortex (V1) as a model system to examine how food restriction affects information coding and energy consumption in cortical networks. We assessed neuronal activity and ATP consumption using whole-cell patch-clamp recordings and two-photon imaging of V1 layer 2/3 excitatory neurons in awake, male mice. We found that food restriction, resulting in a 15% reduction of body weight, led to a 29% reduction in ATP expenditure associated with excitatory postsynaptic currents, which was mediated by a decrease in single-channel AMPA receptor (AMPAR) conductance. Reductions in AMPAR current were compensated by an increase in input resistance and a depolarization of the resting membrane potential, which preserved neuronal excitability; neurons were therefore able to generate a comparable rate of spiking as controls, while spending less ATP on the underlying excitatory currents. This energy-saving strategy, however, had a cost to coding precision. Indeed, we found that an increase in input resistance and depolarization of the resting membrane potential also increased the subthreshold variability of visual responses, which increased the probability for small depolarizations to cross spike threshold, leading to a broadening of orientation tuning by 32%. Broadened tuning was associated with reduced coding precision of natural scenes and behavioral impairment in fine visual discrimination. We found that these deficits in visual coding under food restriction correlated with reduced circulating levels of leptin, a hormone secreted by adipocytes in proportion to fat mass (Baile et al., 2000), and were restored by exogenous leptin supplementation. Our findings reveal key metabolic state-dependent mechanisms by which the mammalian cortex regulates coding precision to preserve energy in times of food scarcity.
New Princeton research shows that prehistoric megatooth sharks—the biggest sharks that ever lived—were apex predators at the highest level ever measured.
Megatooth sharks get their name from their massive teeth, which can each be bigger than a human hand. The group includes Megalodon, the largest shark that ever lived, as well as several related species.
While sharks of one kind or another have existed since long before the dinosaurs—for more than 400 million years—these megatooth sharks evolved after the dinosaurs went extinct and ruled the seas until just 3 million years ago.
Latin Foods Market issued a recall for an Artri King joint supplement, as it contains undeclared diclofenac and dexamethasone.
The US Food and Drug Administration (FDA) published a health warning in mid-April concerning Artri King-branded products. The company makes a pain reliever available as a supplement for joint pain and arthritis. However, FDA testing discovered that Artri King products contain hidden drug ingredients, including diclofenac and dexamethasone.
Walmart already recalled Artri King products in late May, and now Latin Foods Market is following suit with a new recall of its own.
Walmart’s joint supplement recall concerned various Artri King products that may contain undeclared diclofenac. The Latin Foods Market recall covers just one Artri King product that can contain both diclofenac and dexamethasone.
When our phones and computers run out of power, their glowing screens go dark and they die a sort of digital death. But switch them to low-power mode to conserve energy, and they cut expendable operations to keep basic processes humming along until their batteries can be recharged.
Our energy-intensive brain needs to keep its lights on too. Brain cells depend primarily on steady deliveries of the sugar glucose, which they convert to adenosine triphosphate (ATP) to fuel their information processing. When we’re a little hungry, our brain usually doesn’t change its energy consumption much. But given that humans and other animals have historically faced the threat of long periods of starvation, sometimes seasonally, scientists have wondered whether brains might have their own kind of low-power mode for emergencies.
Now, in a paper published in Neuron in January, neuroscientists in Nathalie Rochefort’s lab at the University of Edinburgh have revealed an energy-saving strategy in the visual systems of mice. They found that when mice were deprived of sufficient food for weeks at a time — long enough for them to lose 15%-20% of their typical healthy weight — neurons in the visual cortex reduced the amount of ATP used at their synapses by a sizable 29%.
The brain is the central information center and constantly monitors the state of every organ present in a body. Previous research has shown that the brain also receives signals from the gut microbiota.
In a new Immunity journal study, researchers discuss the work of Gabanyi et al. (2022), published in a recent issue of Science, which reveals that hypothalamic gamma-aminobutyric acid (GABAergic) neurons recognize microbial muropeptides through the cytosolic receptor NOD2, which regulates food intake and body temperature.