70% startups say business hit by COVID-19, 12% have shut down: FICCI

Melbourne, Jul 24: Home-made cloth face masks may need a minimum of two layers, and preferably three, to prevent the dispersal of viral droplets associated with Covid-19, according to a study.

Researchers, including those from the University of New South Wales in Australia, noted that viral droplets are generated by those infected with the novel coronavirus when they cough, sneeze, or speak.

As face masks have been proven to protect healthy people from inhaling infectious droplets as well as reducing the spread from those who are already infected, several types of material have been suggested for these, but based on little or no evidence of how well they work, the scientists said.

In the current study, published in the journal Thorax, the researchers compared the effectiveness of single and double-layer cloth face coverings with a surgical face mask (Bao Thach) at reducing droplet spread.

They said the single layer covering was made from a folded piece of cotton T shirt and hair ties, and the double layer covering was made using the sew method described by the US Centers for Disease Control and Prevention (CDC).

The scientists used a tailored LED lighting system and a high-speed camera to film the dispersal of airborne droplets produced by a healthy person with no respiratory infection, during speaking, coughing, and sneezing while wearing each type of mask.

Their analysis showed that the surgical face mask was the most effective at reducing airborne droplet dispersal, although even a single layer cloth face covering reduced the droplet spread from speaking.

But the study noted that a double layer covering was better than a single layer in reducing the droplet spread from coughing and sneezing.

According to the researchers, the effectiveness of cloth face masks is dependent on the number of layers of the covering, the type of material used, design, fit as well as the frequency of washing.

Based on their observations, they said a home made cloth mask with at least two layers is preferable to a single layer mask.

"Guidelines on home-made cloth masks should stipulate multiple layers," the scientists said, adding that there is a need for more research to inform safer cloth mask design.

In a bid to help struggling small businesses in Covid-19 times, Facebook has introduced Shops to help set up a single online store for customers to access on both Facebook and Instagram.

While Facebook Shops is being rolled out from Wednesday, the company will introduce Instagram Shop, a new way to discover and buy products in Instagram Explore, this summer, starting in the US.

The social networking giant also announced that it will invest in features across its family of apps to inspire people to shop and make buying and selling online easier.

"Creating a Facebook Shop is free and simple. Businesses can choose the products they want to feature from their catalogue and then customise the look and feel of their shop with a cover image and accent colours that showcase their brand," Facebook said in a statement late Tuesday.

Any seller, no matter their size or budget, can bring their business online and connect with customers wherever and whenever it's convenient for them.

People can find Facebook Shops on a business' Facebook Page or Instagram profile, or discover them through stories or ads.

"From there, you can browse the full collection, save products you're interested in and place an order — either on the business' website or without leaving the app if the business has enabled checkout in the US," informed the company.

Last month, Facebook announced $40 million in grants for 10,000 small businesses in the US to help them get through these challenging time.

The grants will go to small businesses in 34 locations where Facebook employees live and work.

The company said that in Facebook Shops, users will be able to message a business through WhatsApp, Messenger or Instagram Direct to ask questions, get support, track deliveries and more.

In the future, they will be able to view a business' shop and make purchases right within a chat in WhatsApp, Messenger or Instagram Direct.

Later this year, Facebook will add a new shop tab in the navigation bar, so people can get to Instagram Shop in just one tap.

Facebook said it is making it easier to shop for products in real time.

Soon, sellers, brands and creators will be able to tag products from their Facebook Shop or catalogue before going live and those products will be shown at the bottom of the video so people can easily tap to learn more and purchase.

"We're starting to test this with businesses on Facebook and Instagram, and we'll roll it out more broadly in the coming months," said the company.

Facebook is also working with partners like Shopify, BigCommerce, WooCommerce, ChannelAdvisor, CedCommerce, Cafe24, Tienda Nube and Feedonomics to support small businesses.

Leiden, Jul 2: Astronomers have discovered a luminous galaxy caught in the act of reionizing its surrounding gas only 800 million years after the Big Bang.

The research, led by Romain Meyer, PhD student at UCL in London, UK, has been presented at the virtual annual meeting of the European Astronomical Society (EAS).

Studying the first galaxies that formed 13 billion years ago is essential to understanding our cosmic origins. One of the current hot topics in extragalactic astronomy is 'cosmic reionization,' the process in which the intergalactic gas was ionized (atoms stripped of their electrons).

Cosmic reionization is similar to an unsolved murder: We have clear evidence for it, but who did it, how and when? We now have strong evidence that hydrogen reionization was completed about 13 billion years ago, in the first billion years of the universe, with bubbles of ionized gas slowly growing and overlapping.

The objects capable of creating such ionized hydrogen bubbles have however remained mysterious until now: the discovery of a luminous galaxy in which 60-100 percent of ionizing photons escape, is likely responsible for ionizing its local bubble. This suggests the case is closer to being solved.

The two main suspects for cosmic reionization are usually 1) a population of numerous faint galaxies leaking ~10 percent of their energetic photons, and 2) an 'oligarchy' of luminous galaxies with a much larger percentage (>50 percent) of photons escaping each galaxy.

In either case, these first galaxies were very different from those today: galaxies in the local universe are very inefficient leakers, with only <2-3 percent of ionizing photons escaping their host. To understand which galaxies governed cosmic reionization, astronomers must measure the so-called escape fractions of galaxies in the reionization era.

The detection of light from excited hydrogen atoms (the so-called Lyman-alpha line) can be used to infer the fraction of escaping photons. On the one hand, such detections are rare because reionization-era galaxies are surrounded by neutral gas which absorbs that signature hydrogen emission.

On the other hand, if this hydrogen signal is detected it represents a 'smoking gun' for a large ionized bubble, meaning we have caught a galaxy reionizing its surroundings. The size of the bubble and the galaxy's luminosity determines whether it is solely responsible for creating this ionized bubble or if unseen accomplices are necessary.

The discovery of a luminous galaxy 800 million years after the Big Bang supports the scenario where an 'oligarchy' of bright leakers emits most of the ionizing photons.

"It is the first time we can point to an object responsible for creating an ionized bubble, without the need for a contribution from unseen galaxies.

Additional observations with the upcoming James Webb Space Telescope will enable us to study further what is likely one of the best suspects for the unsolved case of cosmic reionization," said Meyer.