Tag Archives: Scientist

Covid 19 coronavirus: A blood survey found eight previously undetected cases in New Zealand | Instant News

The janitor who tested positive for Covid-19 was working on the Green and Red zone aircraft on the same day. Video / Mark Mitchell

Scientists have analyzed nearly 10,000 blood samples to show that there are very few undetected cases of Covid-19 in New Zealand.

Learning, just released online prior to peer review, has also offered a useful new basis for the upcoming mass rollout of Pfizer’s vaccine.

To create a picture of the undetectable spread across the country, scientists looked for specific antibodies among 9806 samples collected from New Zealand Blood Service donors between the ages of 16 and 88.

Antibodies play an important role in the immune system against pathogens such as the coronavirus.

Once a new virus is recognized, antibodies are specially made to bind to the “spike protein” and stop it from entering our cells – while signaling other parts of the immune system to destroy foreign invaders.

Antibodies can also act as useful markers of past infections.

It is the sampling of antibodies that scientists have made possible to reveal last month a previously unknown cluster that predated New Zealand’s first officially reported Covid-19 case.

A co-author of the new study, University of Auckland PhD student Alana Whitcombe, said determining a positive sample count for the Sars-Cov-2 antibody could essentially help measure the rate of undetectable transmission and the potential spread of the virus across the country.

That is important, given that there is evidence to suggest that up to 15 percent of people who contract Covid-19 do not show symptoms, but can still be contagious.

When it came to sampling, Whitcombe and colleagues measured the antibodies using a test based on the viral spike protein.

They will previously used the same method to show you how, in a group of 112 New Zealand patients, the Sars-Cov-2 antibody can persist for months after infection.

“That’s important because the survey sample was collected at the end of 2020 – but the first cases of Covid-19 were reported in New Zealand in February 2020,” Whitcombe said.

“Basing our survey on long-lived spike antibodies means we are likely to detect all possible past infections, even those occurring as early as 2020.”

From the total sample, the researcher identified 18 positive samples.

To ensure they can confirm their results, the team also reconfirmed positive samples using two commercially produced surge-based assays.

Six of the 18 people were confirmed to have previous Sars-CoV-2 infection and the other four were from people who had traveled from the UK and Europe, indicating infection outside New Zealand.

The remaining eight “seropositive” samples came from seven different district health councils – equivalent to a total seroprevalence rate of 0.1 percent of the population.

Study co-author and research associate from the University of Auckland, Dr Reuben McGregor said this was only slightly higher than a previously reported prevalence of 0.04 percent.

While their results suggest some undiagnosed infections have occurred, McGregor said it is much lower than the seroprevalence estimate of more than 10 percent reported in an overseas study where the virus was poorly controlled.

“Overall, the survey shows that undetectable community transmission appears to have been restricted in New Zealand and provides serological evidence for our country’s successful elimination,” added study author Associate Professor Nikki Moreland, an immunologist and biomedical scientist at the University of Auckland.

The data also provide a good basis for vaccine rollouts, he said.

“Although the seroprevalence detected in the survey was very low, there is no reason to think that our immunity levels may be affected by a lack of viral circulation.”

Clinical trials and real-world studies abroad have shown that two doses of Pfizer’s vaccine produce antibody levels and an immune response that are in line with – or often superior to – those seen after Covid-19 infection.

“Achieving high vaccine coverage and increasing seropositivity for spike antibodies through vaccination is much safer than uncontrolled circulation of Sars-CoV-2 in the community.”

The researchers note that the study has several limitations – notably that it does not represent all Kiwis, but only those eligible to be donors, and cannot always be relied on to extrapolate from a small number of seropositive cases.

University of Otago clinical and infectious disease microbiologist Professor David Murdoch also emphasized that blood donor populations usually differ from the total population, in terms of age and ethnicity.

“However, the study findings provide evidence that community transmission of undetected Covid-19 has been limited in New Zealand, and is consistent with similar findings from Australia,” he said.

“In contrast, the prevalence is much lower than in regions of North America and Europe where the pandemic is not well controlled.”

Professor James Ussher, Associate Immunologist at the University of Otago, said the findings also highlight the effectiveness of our bold actions to eliminate the virus.

“This study confirms that border locks and restrictions have been very successful in curbing SARS-CoV-2 infection in New Zealand.”


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Switzerland- Study: rivers emit more CO2 at night than during the day | Instant News

(MENAFN Swissinfo) ScExperts in Lausanne have found that rivers and streams – or ‘running water’ – emit four times more carbon dioxide (CO2) on average at night than during the day. The results have implications for how the global carbon cycle is calculated.

This content is published April 16, 2021 – 16:23 April 16, 2021 – 16:23 EPFL / ilj

The research carried out by a team from the Stream and Biofilm and Ecosystem Research Laboratory (link SBERExternal) at the Swiss Federal Institute of Technology Lausanne (EPFL) – together with international colleagues – was published in the journal Nature GeoscienceExternal on Friday.

More CO2 emitted at night ‘indicates that the calculation of how much CO2 this water releases into the atmosphere has been too low, leading to an erroneous estimate of its contribution to the global carbon cycle’, the EPFL statement says on the External link.

Until recently estimates of CO2 – the main greenhouse gas – from flowing water were based on people sampling the water manually.

And that’s where SBER scientists see the computation bias. They found that 90% of the measurements were taken between 8 a.m. and 4 p.m. By comparing these measurements with data collected continuously by automatic sensors, they observed that CO2 emissions actually peak only 10% of the time during this daylight window.


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Australian ‘Black Summer’ Fires Have Shocking Effects on Earth’s Atmosphere | Instant News

The searing destruction of Australia Black Summer forest fires Between 2019 and 2020 provides a glimpse into the reach of fire in our hotter and drier world, and the effects of an unprecedented hell still being measured.

A few weeks ago, scientists observed that the amount of smoke spewed from these flames into the atmosphere rival violent volcanic eruptions. Now, the researchers say the gigantic smoke cloud is so large, it’s measurably heating up the stratosphere for months.

In a new study led by first author and climate model Pengfei Yu from China’s Jinan University, the scientists simulated the appearance and evolution of feathers, showing the worst wildfires ever documented in Australian history leaving a lasting impact on the region’s skies.

“Extreme forest fires can inject smoke into the upper troposphere and even into the stratosphere under favorable meteorological conditions,” the researchers. write on their paper. “The higher the smoke that is injected, the longer the smoke will last and the wider its reach.”

In the case of the Black Summer fires, the flames sent nearly a trillion grams (about 0.9 teragrams) of smoke particles into the stratosphere, which researchers say is the largest number ever documented in the satellite era.

This smoke mass consists of various types of smoke particles, including organic carbon (OC, which includes brown carbon, aka BrC), and carbon black (BC).

Each has a different heat-trapping effect in the atmosphere, with BC trapping the most heat, due to the way it warms the surrounding air after absorbing sunlight.

According to the researchers’ calculations, Black Summer’s plumes are made up of about 2.5 percent black carbon, which helps exert a warming effect in the stratosphere that lasts for the rest of the year.

“Simulations show that smoke remains in the stratosphere during 2020 and measurably warms the stratosphere by about 1-2 K. [Kelvin, equivalent here to 1-2 degrees Celsius] for more than six months, ” the team explained.

“Our study highlights that record-breaking forest fire smoke can have a lasting impact on stratospheric dynamics and chemistry.”

As well as warming the stratosphere, the researchers say record-breaking smoke events will also have a reduced impact ozone levels in the stratosphere, destroying ozone molecules at mid-high latitudes in the Southern Hemisphere, and likely temporarily making the ozone hole bigger.

Meanwhile, researchers admit that observations of aerosols result in warming of the stratosphere was created beforeThis is the first time scientists have measured the phenomenon in such a way, given the record-breaking results of the Black Summer fires.

These findings are reported in Geophysical Research Letter.


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Brood X’s cicadas will not spawn in the north; journey down state required to experience massive emergence | Local News | Instant News

TRAVERSE CITY – A large X brood of cicadas will emerge from the ground after 17 years and start crying trees – but in the north, residents must travel down to enjoy the thrill. with the big clutches, ”said entomologist Duke Elsner, retired Michigan State University Extension educator. Northern Michigan has annual cicadas that come out in cycles each year, a different brood each year for four or five years. “Basically there isn’t enough of it to be really loud,” Elsner said. Annual cicadas are larger and usually black with undertones of green and white, he said, but without the characteristic red eyes of periodic cicadas that emerge by the millions after The Brood X phenomenon – pronounced Brood 10 – will return in parts of southern Michigan this year, scientists say, mostly along the southern state border as well as in Jackson and Washtenaw counties. There are periodic 17 year old cicadas in the Traverse City area and people there will have to travel to Ann Arbor or further south of the United States if they are to experience this mass emergence, ” said Gary Parsons, head of the Arthropod collection at MSU. Research Collection and Director of the MSU Bug House.Cicadas are a type of insect that is distinguished from other species or insects by having their mouthparts modified into the shape of a slender, hinged beak to suck fluids, a-t- he declares. but are not toxic or injurious to people or animals. “Cicadas do not bite and are harmless to humans and property – other than being a nuisance. They can pile up in millions in parks, woods and neighborhoods and seemingly be everywhere. When they’re this plentiful, they fly, land and crawl all over the place, including sometimes landing on humans, ”Parsons said. Female cicadas insert and lay their eggs in thin twigs of trees and shrubs after mating. “When the tiny nymphs hatch, they drop to the ground, burrowing into the ground, then find a root to suck in fluids for the next 13 or 17. Parsons said. The university scientist said Brood X is the largest and most widespread brood in the United States, and the only periodic brood that emerges in Michigan. “As far as I know, the only population that still exists in Michigan is down around Ann Arbor, ”Parsons said. After this year, Brood X won’t reappear until 2038, he said. cycles, due to global warming trends. Insects typically emerge when the soil temperature is 64 degrees and after a rain.Climate Central, a nonprofit news organization that analyzes and reports on climate science, has calculated average soil temperatures across the country. area of ​​emergence of Brood X. It is estimated that Brood X cicadas will emerge between five and 10 days – even up to 15 days or more in parts of the range – earlier than in previous cycles, scientists from the group said. Counties expected to see the bulk of Brood X’s emergence include Branch, Jackson, and St. Joseph, according to a US Forest Service map of planned activity this year. Other sources also include parts of Berrien, Cass, Hillsdale and Washtenaw counties in the cicada landing zone. .

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Scorching ocean: Scientists trace the East Coast’s ‘ocean heat wave’ | Instant News

Scientists are closely watching the unusually warm waters around the North Island’s East Coast – and predict an “ocean heat wave” could develop near Canterbury and Otago within a few days. Image Project / Moana

Scientists are closely watching the unusually warm waters around the North Island’s East Coast – and predict an “ocean heat wave” could develop near Canterbury and Otago within a few days.

Described as an extended period of extremely warm ocean temperatures at a particular location, ocean heat waves can last for several months and cover thousands of square kilometers.

“Scientifically, ocean heat waves are defined when the ocean temperature at a particular location is in the top 10 percent of the temperature normally recorded during that time of the year for five or more days,” explains University of Otago marine scientist Dr Robert Smith.

Events that have never happened before 2017-18 sparked New Zealand’s hottest summer and came with dramatic consequences.

Glaciers are melting as some pockets of sea off the South Island’s West Coast warmed to 6C above average, while elsewhere, seashells are suffering from flowing losses and vineyards are experiencing early harvests.

While sea surface temperatures around New Zealand have been near normal for much of last summer, Smith said a strong ocean heat wave developed during late February to the east of the country – and is still going on.

“This ocean heat wave is currently impacting the coastline of Wairarapa, Hawke’s Bay and Chatham Islands,” he said, adding that it had pushed temperatures more than 2 degrees Celsius above normal.

“The event was somewhat unusual in that it also covered much of New Zealand’s sub-Antarctic zone during the month of March, which is not, as the name implies, an area normally considered to experience a heat wave.”

At these ecological points, warmer oceans can disrupt all kinds of species, from plankton and seaweed to marine mammals and seabirds.

“They may also impact regional fisheries, including for the pāua around the Chatham Islands.”

As part of The Moana Project – a five-year, $ 11.5 million collaboration aimed at making New Zealand the world leader in ocean forecasting capabilities – Smith and fellow Otago researchers are working to gain a clearer understanding of heat waves and their effects.

The project has also seen the file launch free ocean heat wave forecasting system.

“Currently, we provide short distance forecasts of up to seven days, where and when ocean heat waves are most likely to occur, for specific coastal locations around New Zealand,” he said.

“These sites include Hauraki Bay, Bay of Plenty, Cook Strait, and Banks Peninsula. While the current tool provides us with short-term estimates, we are looking for ways to extend this estimate to several months using machine learning techniques.

“This research will help us predict these extreme events with more certainty and provide a warning to our marine industry and important coastal communities.”

This can guide efforts such as early harvesting, or, at a coastal cultivation facility, even moving stocks.

Heat waves can occur relatively quickly, and are triggered by a variety of factors.

“On a local scale, these factors include ocean currents that build up areas of very warm water, warming through the ocean surface from the atmosphere and reduced wind speeds that prevent the mixing of the oceans,” he said.

“The likelihood of ocean heat waves is also influenced by weather and large-scale climate patterns, such as El Niño and La Niña.”

Research has shown that global climate change is also having a big impact, with heat waves becoming 34 percent more frequent, and 17 percent longer, since the mid-20th century.

Even more concerning, Smith said, is that the number of heatwave days has increased by more than 50 percent each year.

“The recent ocean heat wave has had a devastating effect on marine ecosystems around the world,” he said.

“For example, they have triggered widespread mortality of marine species, shifts in the abundance and distribution of commercial and recreational fish stocks and the need to limit or shut down fisheries due to disease outbreaks, or the growth of harmful algae.”

Over time, he said the increased exposure of marine ecosystems to extreme temperatures could lead to “irreversible loss of important species or habitats”, such as seaweed forests and seagrass meadows.

“Ocean heat waves are therefore of serious concern to our marine life around New Zealand, which has been thriving on cooler seas,” he said.

“The impacts associated with ocean heatwaves are also a threat to aquaculture and fisheries, New Zealand’s industry worth over $ 4 billion per year.”

Scientists solve the mystery of shells

Meanwhile, scientists working on another Moana Project study combined Mātauranga Māori – or Māori lore – with other strands of science to solve the shellfish mystery.

Green-lipped mussels are an important cultivated species in New Zealand, and resources are valued at more than $ 300 million a year.

Although the aquaculture industry relies heavily on wild-caught baby mussels, or saliva, it is unclear which wild mussel beds supply them.

“Knowing the source of the splash enables the protection of spawning stocks and thus helps the future-resilient New Zealand shellfish aquaculture industry,” said Moana project and science director João de Souza.

In their new study, University of Victoria marine biologist Professor Jonathan Gardner and his team will put together what he calls a “unique combination” of science to reveal where shellfish larvae come from, how they travel, and where they end up.

Green-lipped mussels are a marine resource worth $ 300 million annually to the New Zealand economy.  Photo / Paul Estcourt
Green-lipped mussels are a marine resource worth $ 300 million annually to the New Zealand economy. Photo / Paul Estcourt

“By doing that we will be able to predict the movement of larvae now and under different climate change scenarios.”

With population genetics, samples from the collected shells are genotyped – a process that effectively provides DNA fingerprinting linking different populations.

Microochemical analysis, which involves using a laser to take small samples of the shells of shells, can also provide a chemical record of the age of the shells, and where they traveled.

Mātauranga Māori offers local ecological knowledge that can help establish the location of the splash-producing clam reefs.

Finally, a physical model of the flow will be combined with biological data to predict and see the movement of green-lipped shellfish larvae in the Bay of Plenty, where the first samples were taken.

A further trip is planned to collect mussel larvae using a “splash line” – a vertical line of saliva-catching ropes for the walking spit to settle down.

After collection, any saliva that settles will undergo micro-chemical analysis.

“While the Bay of Plenty is the focus right now, we will also be sampling from several other areas, including Ninety Mile Beach which is where most of the shellfish spit is caught free,” said Gardner.

It is also hoped that the study, which is expected to take up to two years, will help combat invasive species, inform marine spatial planning efforts, and assist coastal restoration efforts.


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