Consistent Awakening Times

Posted on 15/04/2020 by Boris Clair

One challenge that can make it difficult to create a consistent daily flow is getting up at inconsistent times throughout the week. If I get up at different times that could diverge by an hour or more, I find it difficult to have a consistent morning routine.

Initially I thought it shouldn’t make a big difference if I get up at 5am, 6am, or 7am. As long as I get enough sleep, I can run through my morning routine when I first awaken.

But for some reason, it does make a difference. I find it much harder to get my mind to follow the same morning routine if I try to run through it at different times of day. That could be because the cues are different, especially if I sometimes get up before dawn and sometimes after.

Another factor is how I feel about my awakening time emotionally. Getting up at 5am feels good to me. I feel more disciplined. I love being up before dawn and already gliding through the flow of my morning when the sun greets me.

If I don’t get up till after dawn, I start my day feeling slightly disappointed. The sunlight reminds me that I blew it. I feel that I’ve missed out on that serenely beautiful pre-dawn time that anchors me to my day. If the sun catches me in bed, it means I’ve missed the boat for that day. It corrupts how I feel about the day as a whole, even if I still have a pretty good day overall.

If I sleep in late, like till 6:30am or 7am, it throws off my rhythm. I feel out of sync with what I’m supposed to be doing. When I go downstairs and it’s already light in the kitchen, I feel a bit more confused about what to do. My internal and external cues aren’t the same. I can still generally flow through a decent routine, but it’s more effortful because I have to consciously think about each step. And some part of my mind is wasting energy processing thoughts like, “I should have gotten up at 5am,” or “If I’d gotten up at 5am, I’d already have a new article published by now, which would have been lovely, but now I’m stuck in the quantum universe where I slept in late.”

For these reasons I find that the ideal solution is to awaken at a fixed time each day. That one habit anchors my day. I’ve been doing that consistently lately, and I find that it adds such a beautiful flow to my days. Every day starts with a wondrous gift.

I absolutely love getting out of bed when it’s still dark. I like knowing that I got a few things done while the rest of the world is slumbering. When I write and publish a new article early in my day, it feels like I’m making a personal development breakfast for people to gift them with when they’re ready.

I find it best to do this seven days a week. Taking a day off here and there doesn’t feel like a reward or an easing of discipline. It feels like I’m denying myself the gift of the pre-dawn time that I love so much.

This simple daily discipline is a friend. It’s a trainer. I used to resist it and fight with it a lot, especially when I was younger. I’d rebel against the need for it. And I missed out on many of life’s gifts. Now I’m in tune with the flow of those gifts, and it’s a wonderful place to be.

I like to awaken with an alarm each day. It’s my gentle invitation to begin a fresh, new day. It’s not jarring or unpleasant. It’s the wrapping paper that contains the beautiful gift of that magical morning time. I never use the snooze feature; to do so would be like pushing the gift back in someone’s face.

What’s the first gift you could give yourself to begin each day? How do your best days typically begin? What would happen if you consistently gave yourself that gift every single day?

Coronavirus: We can cope with peak, hospital bosses say

Posted on 15/04/2020 by Boris Clair

Thousands of intensive care and hospital beds remain available as the UK heads for a peak in coronavirus cases.

Health24.com | Covid-19: What we think we know about the epidemiological numbers

Posted on 15/04/2020 by Boris Clair

President Cyril Ramaphosa’s decision to lockdown the country was largely based on epidemiological projections. It was projected that if the SARS-CoV-2-19 virus was allowed to spread unchecked to the extent that 40% of people in the country became infected, more than 350 000 people could die.

The National Institute of Communicable Diseases (NICD) has confirmed that these numbers are already outdated and new models are coming up with new numbers, that are yet to be announced.

The results of Imperial College London modelling published in mid- March, indicated that more than 500 000 people may die from Covid-19 in the United Kingdom, and more than 2.2 million in the United States if no action was taken. This modelling prompted UK Prime Minister Boris Johnson’s announcement of new restrictions on people’s movements. Social distancing measures were also introduced in many parts of the United States.

Referring to the South African model, Alex Welte a research Professor at the Centre of Excellence for Epidemiological Modelling and Analysis at Stellenbosch University pointed out “nobody is expecting an infection rate of 40% at this point”. “If you put your hands in your lap and do nothing that may plausibly be the case,” he said. “If we look at Wuhan in China, by the time the epidemic has withered away to nothing, the attack rate (infection rate) has been less than 1%.”

The numbers are uncertain and there is a lot of debate about whether mortality estimates are too high or too low. So, what is the right number? The right answers, however, are not what epidemiological models are for.

John Brooks, Chief Medical Officer at the US Centre for Disease Control, said in a webinar recently, epidemiologists increasingly use modelling to better understand where an outbreak may spread. “These types of analyses can help strategically direct and ideally preposition preparedness and response resources.” So, for example social isolation reduces transmission, and slows the spread of the disease. Contact tracing catches people before they infect others.

Model-makers have to work with the data they have. A novel virus such as SARS-CoV-2, has a lot of unknowns, he said. “Although modelling is helpful, the widespread dissemination of infection in our hyper connected world as with Covid-19 creates challenges to these kind of prediction analyses,” said Brooks.

Welte said “we do not have sufficiently informative data to tell us where we will be in the next four weeks”. “However, grappling with the data and understanding why it’s not possible to make any robust projection, is telling us what the data is we wish we had. The models become more coherent when the data is making sense. Right now, the data is fragmented and confusing but this is giving food for thought for how we can fix this.”

Like the World Health Organization (WHO), many countries are currently relying on Chinese data where their epidemic has matured. More data is coming from Italy and Spain which have recorded most deaths but this is likely to be outstripped by the United States which has the highest number of infections.

But many of this data is not yet settled, and many questions remain. As we learn more about the various epidemiological numbers, and specifically about these numbers in the South African context, modelling of the epidemic will become more reliable. Here are some of the current estimates for some of the key epidemiological numbers:

The incubation period

If we have been to a country with a high number of Covid-19 cases, even if we do not have symptoms, we have to self-isolate for 14 days. The same goes for those who have mild symptoms. This means staying at home and not leaving the house.But why 14 days exactly?This number is not a thumb suck, but has to do with how viruses invade health cells and replicate. The virus relies on replication to be able to survive. Once it infects someone (a host) it takes some time for the virus to make enough copies of itself that the host begins to shed the virus by coughing and sneezing – ensuring new hosts are created. This is the virus’ incubation period.

For us, the hosts, the incubation period is from the time when we are exposed to the pathogen to the time the virus becomes detectable in the body even if we do not have any symptoms. “It is never a fixed period for most pathogens,” said Professor Jeffrey Mphahlele, Vice President for Research at the South African Medical Research Council.

For SARS-CoV-2, the mean incubation period is five to six days but the range can be anywhere between two to 14 days, “which is why a 14-day isolation period has been settled on”. “For some people the period could be even longer,” Mphahlele said. About 97% of the people who get infected and develop symptoms will do so within 11 to 12 days, and about 99% will do so within 14 days.

If after 14 days the virus is not detected in the body with testing “it’s taken that even if you were exposed to the virus, you were not infected,” said Mphahlele. He said there is a big open question that makes the quarantine recommendations trickier than usual. “It’s not yet clear how common it is for people who are infected, but not showing symptoms, to shed the virus.”

You can find some of the key academic articles on the incubation period here and here.

The infectious period

Mphahlele said “we don’t know exactly how long it takes for people to recover from being infectious”. Some estimates in the literature say it can take up to 12 days on average or more than two weeks depending on the severity of the disease.

Some of the literature from China (Aylward et al, WHO-China mission) shows that in mild to moderate cases it takes two weeks to recover from viral shedding which is quick, but six weeks in severe cases which underscores the need for protective clothing for health workers. Mphahlele added that from the onset of symptoms to death can take up to eight weeks depending on the severity of the disease.

“Death comes quicker depending on underlying illness,” he said. A Lancet Infectious Disease study estimated an average of 18 days from symptom onset to death.

The series interval

The series interval is the time it takes for a second person, that becomes infected, to develop symptoms. So, the shorter the interval, the more contagious the disease and the quicker it can spread through a population. You can think of it as the period of time from when person A transmits the virus to person B, to the point where person B starts showing symptoms and transmitting the virus to person C.

The US Centre for Disease Control estimates this number at 3.96 days, but estimates vary.

The basic reproductive number

Scientists often estimate the contagiousness of a disease with a figure called the basic reproductive number, or R0 (pronounced R-nought.) The Covid-19 virus is currently believed to have an R0 of about 3.

“It is a calculation of the degree of ‘spreadability’ or more simply the number of people a sick person can infect on average in a group that is susceptible to the disease (meaning they don’t already have immunity from a vaccine or from previously fighting off the disease),” said Mphahlele.

Crudely speaking, this means that each infected person is likely to spread the virus to three others. This number can however be reduced through various measures such as social distancing and isolation of infectious persons. If R0 drops below 1, an epidemic begins to wane.

The case fatality rate

There are a number of different ways to measure the deadliness of Covid-19 and the numbers can differ substantially depending on what kind of fatality rate is being used.

The most widely quoted mortality measure is the case fatality rate (CFR). CFR changes as new data comes in. There is also a high degree of variability from country to country. The CFR is the total number of deaths divided by the total number of officially confirmed cases multiplied by 100 in order to give a percentage. (This is a simplification. See this article for more of the complexities with CFRs in the context of Covid-19.)

Korea, is estimated to have a CFR of less than 1 percent while most other countries with significant outbreaks have reported higher rates. According to the British Medical Journal, as of 2 April official statistics showed that 872 deaths had been recorded in Germany from 73 522 confirmed cases, translating to a fatality rate of 1.2%. This compares with fatality rates of 11.9% in Italy, 9% in Spain, 8.6% in the Netherlands, 8% in the UK, and 7.1% in France. Director-General of the WHO, Dr Tedros Adhanom Ghebreyesus, previously mentioned a global rate of about 3.4%.

On 13 April South Africa had 2 272 confirmed cases and 27 confirmed deaths – giving a CFR of around 1.2%. This rate has been rising steadily in recent weeks.

Mphahlele cautioned that this figure only considers confirmed cases but “there are asymptomatic cases and many more mild cases that do not present at hospital who are not being counted, which would bring the death rate significantly down.”

*Adele Baleta is an independent science writer, media consultant and facilitator.

*This article was produced for Spotlight – health journalism in the public interest. Like what you read? Sign up for our newsletter and stay informed.

Adele Baleta

Health24.com | Coronavirus morning update: Another hospital outbreak and a huge PPE donation from China

Posted on 15/04/2020 by Boris Clair

WHAT’S HAPPENING IN SA

Cases update:

The latest number of confirmed cases is 2 415.

The total number of deaths is at 27.

So far, there have been 87 022 tests conducted.

Latest news:

Twelve staff members, including seven healthcare workers, have tested positive for the coronavirus at Mediclinic Morningside in Sandton, the private hospital group has confirmed.

The hospital has now introduced strict access measures, and will disinfect certain areas.

Mediclinic chief clinical officer Dr Stefan Smuts said more than 100 potential contacts were tested after one of its staff members was found to have been infected, adding the 12 employees were currently in isolation.

“[They] will remain so until they are fully recovered. In addition, all contacts are now being monitored and isolation protocols stringently applied where relevant.”

The Gauteng health department is trying to build up much-needed personal protective equipment (PPE) stock for healthcare workers as it continues to fight the spread of Covid-19, according to Health MEC Bandile Masuku.

This as the Bank of China donated 30 000 PPE units to the department at a ceremony on Tuesday.

Masuku said the department continues to carefully calculate its PPE needs as circumstances change daily.

“Last week we received some from the [Patrice] Motsepe Foundation and we are still going to announce more this week.

“We have received stock on Saturday, we are receiving stock today, so we are trying to build up the stock… we are trying to get enough stock so that we have enough for all our workers.”

The number of prisoners that have tested positive for Covid-19 has risen by 49 cases, following an outbreak at the East London Correctional Centre, the national correctional services department has confirmed.

In a statement on Tuesday, the Department of Correctional Services (DCS) said the rise brought the total number of inmate cases to 53, while 23 officials had also tested positive for the virus at the prison.

St Albans Correctional Centre in Port Elizabeth also had its first confirmed case after an official tested positive, while another official at the DCS head office in Tshwane has also been infected.

DCS spokesperson Singabakho Nxumalo told News24 that contact tracing is being done with regards to the official from St Albans. At this stage, though, there is no link between St Albans and East London.

South Africa’s streets are quiet, but the din of phones ringing at the country’s gender-based violence command centre in Tshwane and places of safety around the country is deafening, social workers say. And experts warn that it is likely to get worse.

The call centre receives between 500 and 1 000 calls a day from women and children confined to their homes as part of a 35-day government-mandated lockdown instituted to curb the spike of coronavirus disease cases in the country.

And it’s not unexpected.

During the lockdown, aimed at curbing the spread of Covid-19, many South Africans are stuck at home with their abusers

Social justice, education and children’s rights activist groups are calling on the Minister of Basic Education to act swiftly to restore school feeding schemes during the lockdown, GroundUp reports.

In a joint letter to Basic Education Minister Angie Motshekga, Equal Education, the Equal Education Law Centre, SECTION27, the Centre for Child Law, and the Children’s Institute have made suggestions on how an estimated nine million vulnerable children can continue to access the National School Nutrition Programme (NSNP).

For many children, the free school meal was their only meal of the day.

The organisations say that to date, the minister’s response has been “disappointing” and “untenable”.

A group of 16 suspects made off with five cash registers, money and groceries when they stormed a supermarket in Gatesville, Athlone, on Tuesday afternoon, Western Cape police have confirmed.

Four people have been arrested.

This was one of three incidents reported in one afternoon in Cape Town which has resulted in “reinforced deployments” following burglaries, looting and pubic violence.

Footage of the incident at Shoprite, which took place at 14:40, showed people running from the supermarket carrying baskets and tossing goods into trolleys as they escaped from the scene.

WHAT’S HAPPENING IN THE REST OF THE WORLD

Cases update:

For the latest global data, follow this interactive map from Johns Hopkins University & Medicine.

Positive cases worldwide were more than 1.9 million, while the number of deaths were more than 125 000.

There were more than 590 000 cases in the US, and more than 23 000 deaths.

The US still has the highest number of deaths.

Latest news:

India’s nationwide coronavirus lockdown, the biggest in the world, will be extended until at least 3 May, Prime Minister Narendra Modi said on Tuesday.

The current three-week-old lockdown of the nation of 1.3 billion people had been scheduled to end at midnight on Tuesday.

“From the economic angle, we have paid a big price,” Modi said in a nationwide address. “But the lives of the people of India are far more valuable.”

South Asian nations have so far been relatively unscathed by the epidemic, with around 10 000 cases and 339 deaths in India, according to official figures.

Around 117 million children worldwide risk contracting measles because dozens of countries are curtailing their vaccination programmes as they battle Covid-19, the United Nations warned on Tuesday.

Currently 24 countries, including several already dealing with large measles outbreaks, have suspended widespread vaccinations, the World Health Organization and the UN’s children’s fund Unicef said.

An additional 13 countries have had their vaccination programmes interrupted due to Covid-19.

In a joint statement, the Measles and Rubella Initiative (M&RI) said it was vital that immunisation capacity was retained during and after the current pandemic.

HEALTH TIPS (as recommended by the NICD and WHO)

• Maintain physical distancing – stay at least one metre away from somebody who is coughing or sneezing

• Practise frequent hand-washing, especially after direct contact with ill people or their environment

• Avoid touching your eyes, nose and mouth, as your hands touch many surfaces and could potentially transfer the virus

• Practise respiratory hygiene – cover your mouth with your bent elbow or tissue when you cough or sneeze. Remember to dispose the tissue immediately after use.

READ MORE | Coronavirus 101

^{Image credit: Getty Images}

Health24.com | Can you catch the new coronavirus from your clothes?

Posted on 15/04/2020 by Boris Clair

While many are hunkered down in their homes as coronavirus sweeps across the globe, essential workers still have to go to their jobs, and trips to the grocery store and pharmacy remain necessary. But can the clothing people wear out spread Covid-19?

If so, what is the best way to handle clothes on your return?

That may depend on exactly what you do when you leave the house. For example, the American College of Emergency Physicians (ACEP) urges nurses and doctors to think of hospitals as “hot zones”, and advises them to remove all of their clothing before re-entering their home. An immediate shower or bath is also advised, with work clothing kept away from other clothing until thoroughly washed in hot soapy water.

But for the average person, the role of clothing in infection risk is much less clear.

Hottest water cycle possible

“I have seen nothing published that suggests that people need to strip off clothes, launder and shower right after a trip to the store,” noted Elizabeth Scott, associate dean at Simmons University’s College of Natural, Behavioral, and Health Sciences in Boston. Scott is also the founder of Simmons’ Center for Hygiene and Health in Home and Community.

At this point, “the focus should remain on hand hygiene practices, wearing a mask, and not touching the face” for most people, Scott said.

However, Scott said that as a precaution for store employees, sanitation workers or anyone in routine contact with the public, “It would make sense to remove outer clothing when they get home, and either launder them or leave them hanging until the next shift.” And she advised washing hands right after doing so.

Scott also echoed US Centers for Disease Control and Prevention advice that “laundering should be done using the highest water setting possible, followed by thorough drying”.

“I would always use the hottest water cycle possible for the type of fabrics being washed,” she stressed. “And it is also possible to do a sanitising wash, using household bleach following label instructions.”

The CDC also advises against shaking out dirty laundry, to prevent unintentionally circulating any virus in the air.

What about laundromats?

For those who don’t have a washer and dryer at home, are laundromats safe?

Scott suggested they are, so long as physical distancing is followed. To that end, she advised minimising laundromat time by sorting out dirty laundry in advance and folding clean laundry back at home.

“I would also suggest that you bring your own soap and hand towel,” said Scott, to wipe down the outside of any public washer or dryer you might use. “I would add if you need to use a communal cart or laundry basket, wipe down all of the hand contact surfaces with sanitising wipes or hand sanitiser.”

Finally, Scott took pains to emphasise the importance of maintaining hand hygiene throughout your laundry trip.

“You should wash and dry your hands before you leave home if possible and sanitise your hands once outside the laundry room/laundromat,” Scott said. “And, once you get home, wash and dry your hands again.”

READ | How long can coronavirus survive in the air and on surfaces; and why do you need to wash your hands?

WATCH | How long can the new coronavirus live on surfaces?

READ | How mild, undocumented infections could lead to an even bigger coronavirus spread

^{Image credit:}^{Andy Fitzsimon, Unsplash}

Stop warts from spreading

Posted on 15/04/2020 by Boris Clair

If you have warts, you can spread the virus to other places on your body. Here’s how to stop the spread: 1. Don’t brush, clip, comb or shave areas with warts. 2. Don’t use the same file or nail clipper on warts as you use on healthy nails. 3. Don’t pick at warts. If you can’t keep your hands off, cover your warts with an adhesive bandage. 4. Wash your hands carefully after touching your warts.

April 15, 2020

Common warts. MayoClinic.org. http://www.mayoclinic.org/diseases-conditions/common-warts/basics/definition/con-20021715. Accessed July 2, 2014.

See more In-depth

Products and Services

Six-junction solar cell sets two world records for efficiency

Posted on 14/04/2020 by Boris Clair

Scientists at the National Renewable Energy Laboratory (NREL) have fabricated a solar cell with an efficiency of nearly 50%.

The six-junction solar cell now holds the world record for the highest solar conversion efficiency at 47.1%, which was measured under concentrated illumination. A variation of the same cell also set the efficiency record under one-sun illumination at 39.2%.

“This device really demonstrates the extraordinary potential of multijunction solar cells,” said John Geisz, a principal scientist in the High-Efficiency Crystalline Photovoltaics Group at NREL and lead author of a new paper on the record-setting cell.

The paper, “Six-junction III-V solar cells with 47.1% conversion efficiency under 143 suns concentration,” appears in the journal Nature Energy. Geisz’s co-authors are NREL scientists Ryan France, Kevin Schulte, Myles Steiner, Andrew Norman, Harvey Guthrey, Matthew Young, Tao Song, and Thomas Moriarty.

To construct the device, NREL researchers relied on III-V materials — so called because of their position on the periodic table — that have a wide range of light absorption properties. Each of the cell’s six junctions (the photoactive layers) is specially designed to capture light from a specific part of the solar spectrum. The device contains about 140 total layers of various III-V materials to support the performance of these junctions, and yet is three times narrower than a human hair. Due to their highly efficient nature and the cost associated with making them, III-V solar cells are most often used to power satellites, which prize III-V’s unmatched performance.

On Earth, however, the six-junction solar cell is well-suited for use in concentrator photovoltaics, said Ryan France, co-author and a scientist in the III-V Multijunctions Group at NREL.

“One way to reduce cost is to reduce the required area,” he said, “and you can do that by using a mirror to capture the light and focus the light down to a point. Then you can get away with a hundredth or even a thousandth of the material, compared to a flat-plate silicon cell. You use a lot less semiconductor material by concentrating the light. An additional advantage is that the efficiency goes up as you concentrate the light.”

France described the potential for the solar cell to exceed 50% efficiency as “actually very achievable” but that 100% efficiency cannot be reached due to the fundamental limits imposed by thermodynamics.

Geisz said that currently the main research hurdle to topping 50% efficiency is to reduce the resistive barriers inside the cell that impede the flow of current. Meanwhile, he notes that NREL is also heavily engaged in reducing the cost of III-V solar cells, enabling new markets for these highly efficient devices.

Story Source:

Materials provided by DOE/National Renewable Energy Laboratory. Note: Content may be edited for style and length.

Self-isolation or keep calm and carry on — the plant cell’s dilemma

Posted on 14/04/2020 by Boris Clair

Self-isolation in the face of a marauding pathogen may save lives but it comes at the expense of life-sustaining essentials such as transport, communication and connectivity.

This leaves decision makers with a dreadful dilemma as they judge when it’s time to relax lockdown measures.

New research suggests plants must balance similar trade-offs as they respond to pathogens that could rip through their defence cell by cell.

Plant cells communicate with their neighbours by tunnel-like connections called plasmodesmata. This is one way that cells exchange information and resources.

Plasmodesmata are lined by the same membrane that surrounds the cell and they allow molecules to move from one cell into the surrounding cells.

When a cell perceives a threat like an invading fungus or bacteria, the plasmodesmata close over and the cells are temporarily isolated.

In this study researchers at the John Innes Centre used bioimaging approaches to investigate what proteins are involved in this process of cellular self-isolation.

They show that the cell wall material of fungus — called chitin — triggers different responses in the membrane that lines the plasmodesmal tunnels when compared to the responses it triggers in the membrane that surrounds the cell body.

The signaling cascade in plasmodesmata triggers the production of a polysaccharide called callose that forces the plasmodesmal tunnel to close over and for the cells to isolate themselves.

“This indicates that cells control their connectivity independently of other responses, although we don’t yet know why this is,” explains Dr Christine Faulkner of the John Innes Centre.

The study also finds that guard-like receptors that sit in the plasmodesmata are different from those that sit in the rest of the membrane, but both receptors use the same enzyme.

“This is puzzling,” says Dr Faulkner, “but we also discovered that the mechanism of activation of this enzyme in the plasmodesmata is different to the mechanism used in the rest of the membrane. Thus, it seems that while both receptors use the same tool (the enzyme) to transmit a signal, they use it differently for different purposes.”

The requirement for specific signaling in the plasmodesmal part of the cell membrane suggests that the vital processes requiring cell-to-cell connectivity must be regulated independently of immune response.

The study concludes: “This raises questions whether there is a critical requirement for cells to balance connectivity and resource exchange with a protective mechanism imposed by isolation.”

Story Source:

Materials provided by John Innes Centre. Note: Content may be edited for style and length.

Ultraviolet LEDs prove effective in eliminating coronavirus from surfaces and, potentially, air and water

Posted on 14/04/2020 by Boris Clair

As COVID-19 continues to ravage global populations, the world is singularly focused on finding ways to battle the novel coronavirus. That includes the UC Santa Barbara’s Solid State Lighting & Energy Electronics Center (SSLEEC) and member companies. Researchers there are developing ultraviolet LEDs that have the ability to decontaminate surfaces — and potentially air and water — that have come in contact with the SARS-CoV-2 virus.

“One major application is in medical situations — the disinfection of personal protective equipment, surfaces, floors, within the HVAC systems, et cetera,” said materials doctoral researcher Christian Zollner, whose work centers on advancing deep ultraviolet light LED technology for sanitation and purification purposes. He added that a small market already exists for UV-C disinfection products in medical contexts.

Indeed, much attention of late has turned to the power of ultraviolet light to inactivate the novel coronavirus. As a technology, ultraviolet light disinfection has been around for a while. And while practical, large-scale efficacy against the spread of SARS-CoV-2 has yet to be shown. UV light shows a lot of promise: SSLEEC member company Seoul Semiconductor in early April reported a “99.9% sterilization of coronavirus (COVID-19) in 30 seconds” with their UV LED products. Their technology currently is being adopted for automotive use, in UV LED lamps that sterilize the interior of unoccupied vehicles.

It’s worth noting that not all UV wavelengths are alike. UV-A and UV-B — the types we get a lot of here on Earth courtesy of the Sun — have important uses, but the rare UV-C is the ultraviolet light of choice for purifying air and water and for inactivating microbes. These can be generated only via human-made processes.

“UV-C light in the 260 — 285 nm range most relevant for current disinfection technologies is also harmful to human skin, so for now it is mostly used in applications where no one is present at the time of disinfection,” Zollner said. In fact, the World Health Organization warns against using ultraviolet disinfection lamps to sanitize hands or other areas of the skin — even brief exposure to UV-C light can cause burns and eye damage.

Before the COVID-19 pandemic gained global momentum, materials scientists at SSLEEC were already at work advancing UV-C LED technology. This area of the electromagnetic spectrum is a relatively new frontier for solid-state lighting; UV-C light is more commonly generated via mercury vapor lamps and, according to Zollner, “many technological advances are needed for the UV LED to reach its potential in terms of efficiency, cost, reliability and lifetime.”

In a letter published in the journal ACS Photonics, the researchers reported a more elegant method for fabricating high-quality deep-ultraviolet (UV-C) LEDs that involves depositing a film of the semiconductor alloy aluminum gallium nitride (AlGaN) on a substrate of silicon carbide (SiC) — a departure from the more widely used sapphire substrate.

According to Zollner, using silicon carbide as a substrate allows for more efficient and cost-effective growth of high-quality UV-C semiconductor material than using sapphire. This, he explained, is due to how closely the materials’ atomic structures match up.

“As a general rule of thumb, the more structurally similar (in terms of atomic crystal structure) the substrate and the film are to each other, the easier it is to achieve high material quality,” he said. The better the quality, the better the LED’s efficiency and performance. Sapphire is dissimilar structurally, and producing material without flaws and misalignments often requires complicated additional steps. Silicon carbide is not a perfect match, Zollner said, but it enables a high quality without the need for costly, additional methods.

In addition, silicon carbide is far less expensive than the “ideal” aluminum nitride substrate, making it more mass production-friendly, according to Zollner.

Portable, fast-acting water disinfection was among the primary applications the researchers had in mind as they were developing their UV-C LED technology; the diodes’ durability, reliability and small form factor would be a game changer in less developed areas of the world where clean water is not available.

The emergence of the COVID-19 pandemic has added another dimension. As the world races to find vaccines, therapies and cures for the disease, disinfection, decontamination and isolation are the few weapons we have to defend ourselves, and the solutions will need to be deployed worldwide. In addition to UV-C for water sanitation purposes, UV-C light could be integrated into systems that turn on when no one is present, Zollner said.

“This would provide a low-cost, chemical-free and convenient way to sanitize public, retail, personal and medical spaces,” he said.

For the moment, however, it’s a game of patience, as Zollner and colleagues wait out the pandemic. Research at UC Santa Barbara has slowed to a trickle to minimize person-to-person contact.

“Our next steps, once research activities resume at UCSB, is to continue our work on improving our AlGaN/SiC platform to hopefully produce the world’s most efficient UV-C light emitters,” he said.

Other research contributors include Burhan K. SaifAddin (lead author), Shuji Nakamura, Steven P. DenBaars, James S. Speck, Abdullah S. Almogbel, Bastien Bonef, Michael Iza, and Feng Wu, all from SSLEEC and/or the Department of Materials at UC Santa Barbara.

Coronavirus: One in five deaths now linked to virus

Posted on 14/04/2020 by Boris Clair

Coronavirus prompts spike in mortality with data showing weekly deaths have hit a record high.

WellnessMaster

Get The Latest News on Holistic Wellness

Category Archives: Mind Building

Consistent Awakening Times

Coronavirus: We can cope with peak, hospital bosses say