Monday, 26 October 2020

The Moon Is Getting Cell Service

 NASA wants any human presence on the Moon to have a great cell signal, so it’s investing in a lunar 4G network.

Researchers discover new glands in throat: tubarial glands

 Researchers have found previously unnoticed salivary glands in the human throat.

the new discovery as "tubarial glands," which represents the human body's "fourth pair of major salivary glands."

What is Gene therapy for sight ?

Human trials for genetic jab that lets blind mice see again.

A gene therapy that could restore the fading sight of the elderly is being tested on humans for the first time after positive results in blind mice.

It could be used to treat age-related macular degeneration, a common condition that usually first affects people in their 50s and 60s, scientists said.

It involves a one-time injection of a modified virus into the eye. This viral vector is altered to contain a synthetic gene that produces a protein that plays a critical role in the perception of light.

The gene at the heart of the treatment provides the code for cells in the eye to make a light-sensing protein called MCO1. This is known as an opsin, a molecule involved in the cascade of signals between cells that gives rise to sight. In a healthy eye, opsins are produced by cells known as rod and cone photoreceptors in the retina.

When activated by light, these photoreceptors send a signal through other retinal neurons, the optic nerve, and on to neurons in the brain.

a Rare Brain-Eating Disease Is Becoming More Common ?

 As Japan's Population Ages, a Rare Brain-Eating Disease Is Becoming More Common.

Over the last 15 years, an extremely rare neurodegenerative disease that eats holes into the human brain has grown increasingly common in Japan.

How the Venus Flytrap ‘Remembers’ When It Captures Prey ?

 The carnivorous plant is believed to have something akin to a short-term "memory." A team of scientists has uncovered new details on how it works.

Scientists are continuing to tease out the mechanisms by which the Venus flytrap can tell when it has captured a tasty insect as prey as opposed to an inedible object (or just a false alarm). There is evidence that the carnivorous plant has something akin to a short-term "memory," and a team of Japanese scientists has found evidence that the mechanism for this memory lies in changes in calcium concentrations in its leaves, according to a recent paper published in the journal Nature Plants.

T he Venus flytrap attracts its prey with a pleasing fruity scent. When an insect lands on a leaf, it stimulates the highly sensitive trigger hairs that line the leaf. When the pressure becomes strong enough to bend those hairs, the plant will snap its leaves shut and trap the insect inside. Long cilia grab and hold the insect in place, much like fingers, as the plant begins to secrete digestive juices. The insect is digested slowly over five to 12 days, after which the trap reopens, releasing the dried-out husk of the insect into the wind.

Back in 2016, a team of German scientists discovered that the Venus flytrap can actually "count" the number of times something touches its hair-lined leaves—an ability that helps the plant distinguish between the presence of prey and a small nut or stone, or even a dead insect. The scientists zapped the leaves of test plants with mechano-electric pulses of different intensities and measured the responses. It turns out that the plant detects that first "action potential" but doesn't snap shut right away, waiting until a second zap confirms the presence of actual prey, at which point the trap closes.

But the Venus flytrap doesn't close all the way and produce digestive enzymes to consume the prey until the hairs are triggered three more times (for a total of five stimuli). The German scientists likened this behavior to performing a rudimentary cost-to-benefit analysis, in which the number of triggering stimuli help the Venus flytrap determine the size and nutritional content of any potential prey struggling in its maw and whether it's worth the effort. If not, the trap will release whatever has been caught within 12 hours or so. (Another means by which the Venus flytrap tells the difference between an inedible object and actual prey is a special chitin receptor. Most insects have a chitin exoskeleton, so the plant will produce even more digestive enzymes in response to the presence of chitin.)

The implication is that the Venus flytrap must have some sort of short-term memory mechanism in order for that to work, since it has to "remember" the first stimulation long enough for the second stimulation to register. Past research has posited that shifts in the concentrations of calcium ions play a role, although the lack of any means to measure those concentrations, without damaging the leaf cells, prevented scientists from testing that theory.

That's where this latest study comes in. The Japanese team figured out how to introduce a gene for a calcium sensor protein called GCaMP6, which glows green whenever it binds to calcium. That green fluorescence allowed the team to visually track the changes in calcium concentrations in response to stimulating the plant's sensitive hairs with a needle.