Hexbyte Glen Cove Chinese astronomers investigate X-ray bursts of SGR J1935+2154 thumbnail

Hexbyte Glen Cove Chinese astronomers investigate X-ray bursts of SGR J1935+2154

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SGR J1935+2154: Examples of short-duration bursts inspected in the study. Credit: Zou et al., 2021.

By analyzing the data from NASA’s Fermi spacecraft, astronomers from the Hebei Normal University and Nanjing University in China, have investigated X-ray bursting activity of a soft gamma-ray repeater (SGR) known as SGR J1935+2154. Results of the study, published July 9 on arXiv.org, deliver more hints about the properties of X-ray bursts from this source.

SGRs are sources emitting large bursts of gamma-rays and X-rays at irregular intervals. They are known to be magnetars, isolated neutron stars with ultra-strong magnetic fields. SGRs emit X-rays in their quiescent state, and outbursts occur when the intense magnetic field shifts. Based on their brightness, the SGR bursts can be divided into three classes: short-duration bursts, giant flares, and intermediate burts.

At a distance of about 30,000 , SGR J1935+2154 is a soft gamma-ray repeater discovered in 2014 by NASA’s Neil Gehrels Swift Observatory. To date, the source has experienced several periods (windows) of activity in 2014, 2015, 2016, 2019 and 2020. When it comes to April 2020, it was recognized as the most violent bursting month of this SGR so far.

Previous observations of SGR J1935+2154 suggested a periodic window behavior (PWB) for its bursting activity, which means that bursting phases always appear periodically, but there is no periodicity for specific bursts. In order to further investigate this hypothesis, a team of astronomers led by Jin-Hang Zou (Hebei Normal University/Nanjing University) has conducted a systematic search for X-ray bursts of this SGR using the data from the Gamma-ray Burst Monitor (GBM) onboard Fermi, hoping to identify its PWB.

“We performed a systematic search for X-ray bursts of the SGR J1935+2154 using the Fermi Gamma-ray Burst Monitor continuous data dated from Jan 2013 to July 2021,” the researchers wrote in the paper.

By analyzing the Fermi data, Zou’s team has identified eight bursting phases of SGR J1935+2154, consisting of a total of 255 individual bursts. Further analysis of this dataset using two independent methods allowed them to find that the bursts exhibit a period of approximately 237 days with an about 58.6 percent duty cycle.

These results are fully consistent with all the X-ray bursts of SGR J1935+2154 observed by multiple missions to date. Moreover, the findings suggest that the next active windows will occur June-November 2021 and February-July 2022. The first predicted window was confirmed by the current ongoing burst activities of SGR J1935+2154, which started on June 26, 2021.

Trying to explain the physical origin of the identified 237-day period of bursts, the astronomers assume that the most natural way to cause such a period may be the free precession of the magnetar.

“Given that there is no evidence showing SGR J1935+2154 are in a binary system, we focus on the explanations invoking the properties of the magnetar itself,” the authors of the paper wrote in concluding remarks.



More information:
Periodicity Search on X-ray Bursts of SGR J1935+2154 Using 8.5-year Fermi/GBM Data, arXiv:2107.03800 [astro-ph.HE] arxiv.org/abs/2107.03800

© 2021 Science X Network

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Chinese astronomers investigate X-ray bursts of SGR J1935+2154 (2021, July 19)
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Hexbyte Glen Cove Climate change is forcing conservationists to be more ambitious thumbnail

Hexbyte Glen Cove Climate change is forcing conservationists to be more ambitious

Hexbyte Glen Cove

As climate change brings record droughts and floods, extended fire seasons continue to make headlines, and the role of humans in this terrible situation is now undisputed, institutional change has been slow and unsteady. In particular, conservationists have been wary of pointing to climate change as the biggest threat to biodiversity, given the many other threats that exist.

But the situation may now be changing. In the last 18 months, the IUCN Red List—which lists species’ extinction risk status—recorded a 52% increase in species listed as being threatened by climate change. Conservationists are being forced to consider whether their conventional approach of maintaining, not changing ecosystems, needs to be adapted to a changing world.

You may have heard of situations where threatened species are released back into areas they used to occupy in the wild. Examples include the restoration of rhinos in Africa and wolves in North America.

However, in our research, my colleagues and I showed that many failed reintroductions are taking place in regions where the climate isn’t suitable for the species being released.

This undermines attempts to protect species in their former habitats and is a warning that climate change is already restricting the habitat of threatened species.

In some cases, new habitats become available as the change in climate conditions allows species to survive in areas that were previously too cool. But unless they can populate these new habitats—an adjustment which is tricky for most—many threatened species will experience a reduction in their current range.

“Conservation translocation”, also known as assisted migration, assisted colonization and managed relocation, describes interventions that could be used to tackle climate change-driven species declines and extinctions.

Instead of leaving species to suffer in hotter and drier environments, we can try to expand their range by moving them to new habitats. This overcomes situations where species can’t move by themselves, such as plants whose seeds disperse only a few meters at a time, or birds who won’t leave the safety of their woodland home to seek new territory.

However, this approach remains controversial due to the perceived risks of moving species to ecosystems they’ve never experienced before. Risks include spreading diseases into new habitats, aggressive competition with resident species for prey or space, and the introduction of new predators.

An example of this last problem is that of the Tasmanian devils moved to Maria Island off the coast of Tasmania, to protect against a contagious cancer ripping through their population.

These predators found an easy supply of prey in the form of short-tailed shearwaters (also known as moonbirds) and little penguins, themselves species of concern. Both bird species have now been eradicated from Maria Island.

But translocations are a conservation option that we can’t just dismiss. A new paper on assisted migration from a team of international researchers calls for the risks of translocation to be balanced against the risks of doing nothing at all. Given the immediacy of the climate crisis, it is now the path of least risk that we must take.

The complex relationships between species are easily disrupted by new predators. Credit: Wikimedia, CC BY

Early days

There are only a handful of attempted assisted migrations undertaken specifically to reduce the negative effects of a warming world.

A good example is the western swamp turtle: Australia’s rarest reptile, thought to be extinct for a century but recently discovered near Perth. The turtle feeds in ephemeral pools that appear after seasonal rains, but droughts are shortening their feeding window by several weeks: with consequences for the species’ reproductive success.

For the western swamp turtle, translocations to cooler, wetter sites to the south of their current range offer the right type of habitat and enough food to survive ongoing droughts. These appear to be the safest long-term place for the turtles to thrive, and trial translocations are already reporting good results.

Time to act?

Plants are in a similar predicament. In a recent collection of papers in the Journal of Ecology, a group of Italian researchers estimated under pessimistic (but highly probable) scenarios that 90% of 188 threatened plant species may need assisted migration to cope with habitat loss.

A historical marker in Torreya State Park explains the history of the Torreya tree. Credit: Wikimedia, CC BY

But while researchers are using computer models to predict the future needs of threatened species, one group has decided that the time to act is now. The Florida torreya, the most endangered coniferous tree in the US, has been moved north by a group of citizens known as the Torreya Guardians. They exploited a loophole in US law that allows plant translocations on private land by the public but prevents federal conservation authorities from doing the same thing.

The species’ is extremely restricted but was much more widespread before the last global ice age. The Torreya Guardians argue that the specimens of Florida torreya growing across the US provide evidence that the can thrive beyond its current restrictions.

With new temperature records being set all the time—and melting ice, sea-level rise and historic droughts affecting the whole planet—it’s only a matter of time before -induced extinctions become a regular feature in the headlines.

It’s time for calls for better global policy on assisted migration to be heeded. We need guidance so that we, as a global community of concerned citizens and conservation scientists alike, can act decisively to protect the survival of .



This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Climate change is forcing conservationists to be more ambitious (2021, July 19)
retrieved 20 July 2021
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Hexbyte Glen Cove Novel coronavirus discovered in British bats thumbnail

Hexbyte Glen Cove Novel coronavirus discovered in British bats

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The genomic structure of RhGB01 within the (A) entire genome, and (B) non-structural proteins. (C) Read depth across the genome of RhGB01. Read depth is shown per base across the entire genome from the alignment of Illumina (blue), Nanopore (orange) and combined raw reads (green). The lengths of the genomic features in RhGB01 are 5′UTR (279 bp), ORF1ab (21 kb), S (3.7 kb), ORF3a (813 bp), E (231 bp), M (669 bp), ORF6 (189 bp), ORF7ab (465 bp), N (1.2 kb), ORF10 (78 bp). Total genome length is 29,324 bp. Credit: DOI: 10.1038/s41598-021-94011-z

A coronavirus related to the virus that causes COVID-19 in humans has been found in UK horseshoe bats—according to new collaborative research from the University of East Anglia, ZSL (Zoological Society of London), and Public Health England (PHE).

However, there is no evidence that this novel has been transmitted to humans, or that it could in future, unless it mutates.

UEA researchers collected fecal samples from more than 50 lesser horseshoe bats in Somerset, Gloucestershire and Wales and sent them for viral analysis at Public Health England.

Genome sequencing found a novel coronavirus in one of the bat samples, which the team have named “RhGB01.”

It is the first time that a sarbecovirus (SARS-related coronavirus) has been found in a lesser horseshoe bat and the first to be discovered in the UK.

The research team say that these bats will almost certainly have harbored the virus for a very long time. And it has been found now, because this is the first time that they have been tested.

Importantly, this is unlikely to pose a direct risk to humans, unless it mutates.

A mutation could happen if a human infected with COVID-19 passes it to an infected bat, so anyone coming into contact with bats or their droppings, for example those engaged in caving or bat protection, should wear appropriate PPE.

Prof Diana Bell, an expert in emerging zoonotic diseases from UEA’s School of Biological Sciences, said: “Horseshoe bats are found across Europe, Africa, Asia and Australia and the bats we tested lie at the western extreme of their range.

“Similar viruses have been found in other horseshoe bat species in China, South East Asia and Eastern Europe.

“Our research extends both the geographic and species ranges of these types of viruses and suggests their more widespread presence across more than 90 species of horseshoe bats.

“These bats will almost certainly have harbored this virus for a very long time—probably many thousands of years. We didn’t know about it before because this is the first time that such tests have been carried out in UK bats.

“We already know that there are different coronaviruses in many other mammal species too,” she said. “This is a case of ‘seek and you will find.”

“Research into the origins of SARS-CoV-2, the virus that causes COVID-19 in humans, has focussed on horseshoe bats—but there are some 1,400 other bat species and they comprise 20 percent of known mammals.

“Our findings highlight the need for robust genotype testing for these types of viruses in bat populations around the world. And it raises an important question about what other animals carry these types of viruses.”

Prof Andrew Cunningham, from the Zoological Society of London, said: “Our findings highlight that the natural distribution of sarbecoviruses and opportunities for recombination through intermediate host co-infection have been underestimated.

“This UK virus is not a threat to humans because the receptor binding domain (RBD) – the part of the virus that attaches to host cells to infect them—is not compatible with being able to infect human cells.

“But the problem is that any bat harboring a SARS-like coronavirus can act as a melting pot for virus mutation. So if a bat with the RhGB01 infection we found were to become infected with SARS-CoV-2, there is a risk that these viruses would hybridize and a new virus emerge with the RBD of SARS-CoV-2, and so be able to infect people.

“Preventing transmission of SARS-CoV-2 from humans to bats, and hence reducing opportunities for virus mutation, is critical with the current global mass vaccination campaign against this virus.”

Prof Bell added: “The main risks would be for example a bat rehabilitator looking after a rescued animal and infecting it with SARS-CoV2—which would provide an opportunity for genetic recombination if it is already carrying another sarbecovirus.

“Anyone coming into contact with bats or their droppings, such as bat rescuers or cavers, should wear appropriate PPE—in order to reduce the risk of a mutation occurring.

“We need to apply stringent regulations globally for anyone handling bats and other wild animals,” she added.

The new virus falls within the subgroup of coronaviruses called sarbecoviruses which contains both SARS-CoV-2 (responsible for the current pandemic) and SARS-CoV (responsible for the initial 2003 SARS outbreak in humans).

Further analysis compared the virus with those found in other horseshoe bat species in China, South East Asia and Europe and showed that its closest relative was discovered in a Blasius’s bat from Bulgaria in 2008.

The UK discovery was made by undergraduate ecology student Ivana Murphy, from UEA’s School of Biological Sciences, who collected bat droppings as part of her final year research dissertation. Jack Crook conducted the genetic analyses in partnership with other researchers at PHE.

A total of 53 bats were captured, and their feces collected in sterile bags. The research was conducted under strict Health and Safety protocols. Full PPE was worn and Ivana was regularly tested for COVID-19 to avoid any chance of cross contamination. The bats were released immediately after their droppings had been collected.

Ivana said: “More than anything, I’m worried that people may suddenly start fearing and persecuting bats, which is the last thing I would want and would be unnecessary. As like all wildlife, if left alone they do not pose any threat.”

“Metagenomic identification of a new sarbecovirus from in Europe” is published in the journal Scientific Reports on July 19, 2021.



More information:
Jack M. Crook et al, Metagenomic identification of a new sarbecovirus from horseshoe bats in Europe, Scientific Reports (2021). DOI: 10.1038/s41598-021-94011-z

Citation:
Novel coronavirus discovered in British bats (2021, July 19)
retrieved 20 July 2021
from https://phys.org/news/2021-07-coronavirus-british.html

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Hexbyte Glen Cove Cannabis first domesticated 12,000 years ago: study thumbnail

Hexbyte Glen Cove Cannabis first domesticated 12,000 years ago: study

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Cannabis has been used for millennia for textiles and for its medicinal and recreational properties.

Cannabis was first domesticated around 12,000 years ago in China, researchers found, after analyzing the genomes of plants from across the world.

The study, published in the journal Science Advances on Friday, said the genomic history of cannabis had been under-studied compared to other crop species, largely due to .

The researchers compiled 110 whole genomes covering the full spectrum of wild-growing feral plants, landraces, historical cultivars, and modern hybrids of plants used for and drug purposes.

The study said it identified “the time and origin of domestication, post-domestication divergence patterns and present-day genetic diversity”.

“We show that cannabis sativa was first domesticated in early Neolithic times in East Asia and that all current hemp and drug cultivars diverged from an ancestral gene pool currently represented by feral plants and landraces in China,” it said.

Cannabis has been used for millennia for textiles and for its medicinal and recreational properties.

The evolution of the cannabis genome suggests the plant was cultivated for multipurpose use over several millennia.

The current highly-specialized hemp and drug varieties are thought to come from selective cultures initiated about 4,000 years ago, optimized for the production of fibers or cannabinoids.

The selection led to unbranched, tall hemp plants with more fiber in the main stem, and well-branched, short marijuana with more flowers, maximizing resin production.

Cannabis landraces in Qinghai province, central China. Credit: Guangpeng Ren

‘New insights’

The study was led by Luca Fumagalli of the University of Lausanne and involved scientists from Britain, China, India, Pakistan, Qatar and Switzerland.

“Our genomic dating suggests that early domesticated ancestors of hemp and drug types diverged from Basal cannabis”, around 12,000 years ago, “indicating that the species had already been domesticated by early Neolithic times”, it said.

“Contrary to a widely-accepted view, which associates cannabis with a Central Asian center of crop domestication, our results are consistent with a single domestication origin of in East Asia, in line with early archaeological evidence.”

It said that some of the currently found in China represent the closest descendants of the ancestral gene pool from which hemp and marijuana varieties have since derived.

“East Asia has been shown to be an important ancient hot spot of domestication for several crop species… our results thus add another line of evidence,” the study said.

The researchers said their study offered an “unprecedented” base of genomic resources for ongoing molecular breeding and functional research, both in medicine and in agriculture.

The study, they said, also “provides new insights into the domestication and global spread of a plant with divergent structural and biochemical products at a time in which there is a resurgence of interest in its use, reflecting changing social attitudes and corresponding challenges to its legal status in many countries.”



More information:
G. Ren el al., “Large-scale whole-genome resequencing unravels the domestication history of Cannabis sativa,” Science Advances (2021). advances.sciencemag.org/lookup … .1126/sciadv.abg2286

© 2021 AFP

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Cannabis first domesticated 12,000 years ago: study (2021, July 17)
retrieved 18 July 2021
from https://phys.org/news/2021-07-cannabis-domesticated-years.html

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Hexbyte Glen Cove California fire cancels bike ride, prompts evacuations thumbnail

Hexbyte Glen Cove California fire cancels bike ride, prompts evacuations

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Smoke rises from the Dixie Fire burning along Highway 70 in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger

A rapidly growing wildfire south of Lake Tahoe forced evacuations of a mountain town and the cancellation of an extreme bike ride through the Sierra Nevada, leaving thousands of riders and spectators stranded Saturday.

The Tamarack Fire, which was sparked by lightning on July 4, exploded overnight to about 10 square miles (26 square kilometers) and was burning near the small town of Markleeville, close to the California-Nevada state line. It has destroyed at least 3 structures, authorities said. A notice posted on the 103-mile (165-kilometer) Death Ride’s website said several communities in the area had been evacuated and ordered all riders to also evacuate immediately.

Meanwhile, the largest wildfire in the U.S.—burning in southern Oregon—grew significantly overnight as dry and windy conditions took hold in the area, but containment of the inferno more than tripled as firefighters began to gain more control, authorities said Saturday.

The Bootleg Fire grew to 427 square miles (1,105 square kilometers) and was just one of numerous fires burning across the drought-stricken U.S. West, as new fires popped up or grew rapidly in Oregon and California. There were 70 active large fires and complexes of multiple fires that have burned nearly 1,659 square miles (4,297 square kilometers) in the U.S., the National Interagency Fire Center said.

In this photo provided by the Bootleg Fire Incident Command, the Bootleg Fire burns at night near Highway 34 in southern Oregon on Thursday, July 15, 2021. Firefighters scrambled Friday to control a raging inferno in southeastern Oregon that’s spreading miles a day in windy conditions, one of numerous wildfires across the U.S. West that are straining resources. The Bootleg Fire, the largest wildfire burning in the U.S., has torched more than 377 square miles (976 square kilometers), and crews had little control of it. Credit: Jason Pettigrew/Bootleg Fire Incident Command via AP

A fire in the mountains of northeast Oregon was also growing rapidly and was 15 square miles (39 kilometers) in size on Saturday. The Elbow Creek fire started Thursday and has prompted evacuations in several small, around the Grande Ronde River about 30 miles (50 kilometers) southeast of Walla Walla, Washington.

In southern Oregon, fire crews have dealt with dangerous and extreme fire conditions, including massive “ clouds” that rise up to 6 miles (10 kilometers) above the blaze. Earlier in the week, firefighters had to retreat after one of these clouds started to collapse, threatening them with strong downdrafts and flying embers.

The Bootleg Fire has destroyed at least 67 homes and 117 outbuildings and flames are surging up to 4 miles (6 kilometers) a day.

The conflagration has forced 2,000 people to evacuate and is threatening 5,000 buildings, including homes and smaller structures in a rural area just north of the California border. The main Oregon blaze was 22% contained.

  • In this photo provided by the Bootleg Fire Incident Command, the Bootleg Fire burns at night near Highway 34 in southern Oregon on Thursday, July 15, 2021. Firefighters scrambled Friday to control a raging inferno in southeastern Oregon that’s spreading miles a day in windy conditions, one of numerous wildfires across the U.S. West that are straining resources. The Bootleg Fire, the largest wildfire burning in the U.S., has torched more than 377 square miles (976 square kilometers), and crews had little control of it. Credit: Jason Pettigrew/Bootleg Fire Incident Command via AP
  • In this photo taken with a drone provided by the Bootleg Fire Incident Command, a pyrocumulus cloud, also known as a fire cloud, is seen over the Bootleg Fire in southern Oregon on Wednesday, July 14, 2021. Smoke and heat from a massive wildfire in southeastern Oregon are creating “fire clouds” over the blaze—dangerous columns of smoke and ash that can reach up to 30,000 feet (9,144 meters) and are visible for more than 100 miles (160 kilometers) away. Authorities have put these clouds at the top of the list of the extreme fire behavior they are seeing on the Bootleg Fire, the largest wildfire burning in the U.S. Credit: Bootleg Fire Incident Command via AP
  • In this photo provided by the Bootleg Fire Incident Command, smoke from the Bootleg Fire rises behind the town of Bonanza, Ore., on Thursday, July 15, 2021. Firefighters scrambled Friday to control a raging inferno in southeastern Oregon that’s spreading miles a day in windy conditions, one of numerous wildfires across the U.S. West that are straining resources. The Bootleg Fire, the largest wildfire burning in the U.S., has torched more than 377 square miles (976 square kilometers), and crews had little control of it. Credit: Bootleg Fire Incident Command via AP
  • In this photo provided by the Bootleg Fire Incident Command, columns of smoke from the Bootleg Fire rise behind a water tender in southern Oregon on Friday, July 16, 2021. Firefighters scrambled Friday to control a raging inferno in southeastern Oregon that’s spreading miles a day in windy conditions, one of numerous wildfires across the U.S. West that are straining resources. The Bootleg Fire, the largest wildfire burning in the U.S., has torched more than 377 square miles (976 square kilometers), and crews had little control of it. Credit: Lisa Chambers/Bootleg Fire Incident Command via AP
  • Smoke billows behind power lines as the Dixie Fire burns along Highway 70 in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger
  • Jessica Bell watches as the Dixie Fire burns along Highway 70 in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger
  • Jessica Bell takes a video as the Dixie Fire burns along Highway 70 in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger
  • Jessica and Benjamin Bell watch as the Dixie Fire burns along Highway 70 in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger
  • Benjamin Bell watches as the Dixie Fire burns along Highway 70 in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger
  • Firefighters spray water from Union Pacific Railroad’s fire train while battling the Dixie Fire in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger
  • Firefighters spray water from Union Pacific Railroad’s fire train while battling the Dixie Fire in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger
  • Firefighters spray water from Union Pacific Railroad’s fire train while battling the Dixie Fire in Plumas National Forest, Calif., on Friday, July 16, 2021. Credit: AP Photo/Noah Berger

A Red Flag weather warning was issued for the area through Saturday night.

Extremely and tied to have swept the region, making wildfires harder to fight. Climate change has made the West much warmer and drier in the past 30 years and will continue to make weather more extreme and wildfires more frequent and destructive.

Firefighters said in July they were facing conditions more typical of late summer or fall.



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California fire cancels bike ride, prompts evacuations (2021, July 17)
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Hexbyte Glen Cove Experts: Europe floods shows need to curb emissions, adapt thumbnail

Hexbyte Glen Cove Experts: Europe floods shows need to curb emissions, adapt

Hexbyte Glen Cove

People use rubber rafts in floodwaters after the Meuse River broke its banks during heavy flooding in Liege, Belgium, Thursday, July 15, 2021. Heavy rainfall is causing flooding in several provinces in Belgium with rain expected to last until Friday. Credit: AP Photo/Valentin Bianchi

Just as the European Union was announcing plans to spend billions of euros to contain climate change, massive clouds gathered over Germany and nearby nations to unleash an unprecedented storm that left death and destruction in its wake.

Despite ample warnings, politicians and weather forecasters were shocked at the ferocity of the precipitation that caused flash flooding that claimed more than 150 lives this week in the lush rolling hills of Western Europe.

Climate scientists say the link between extreme weather and global warming is unmistakable and the urgency to do something about climate change undeniable.

Scientists can’t yet say for sure whether climate change caused the flooding, but they insist that it certainly exacerbates the extreme weather that has been on show from the western U.S. and Canada to Siberia to Europe’s Rhine region.

“There is a clear link between extreme precipitation occurring and climate change,” Wim Thiery, a professor at Brussels University, said Friday.

Stefan Rahmstorf, a professor of ocean physics at the University of Potsdam, referring to the recent heat records set in the U.S. and Canada, said “some are so extreme that they would be virtually impossible without global warming..”

Taking them all together, said Sir David King, chair of the Climate Crisis Advisory Group, “these are casualties of the climate crisis: we will only see these extreme weather events become more frequent.”

This image provided on Friday, July 16, 2021 by the Cologne district government shows the Blessem district of Erftstadt in Germany. Rescuers were rushing Friday to help people trapped in their homes in the town of Erftstadt, southwest of Cologne. Regional authorities said several people had died after their houses collapsed due to subsidence, and aerial pictures showed what appeared to be a massive sinkhole. Credit: Rhein-Erft-Kreis via AP

For Diederik Samsom, the European Commission’s Cabinet chief behind this week’s massive proposals to spend billions and force industry into drastic reforms to help cut the bloc’s emissions of the gases that cause global warming by 55% this decade, this week’s disaster was a cautionary tale.

“People are washed away in Germany … and Belgium and the Netherlands, too. We are experiencing climate change,” he said on a conference call of the European Policy Centre think tank. “A few years ago, you had to point to a point in the future or far away on the planet to talk about climate change. It’s happening now—here.”

And climate scientists point toward two specific things that have contributed to this week’s calamity.

First, with every 1 degree Celsius (1.8 degrees Fahrenheit) rise in temperature, the air can take in 7% more humidity. It can hold the water longer, leading to drought, but it also leads to an increase in dense, massive rainfall once it releases it.

The Ahr river floats past destroyed houses in Insul, Germany, Thursday, July 15, 2021. Due to heavy rain falls the Ahr river dramatically went over the banks the evening before. Credit: AP Photo/Michael Probst

Another defining factor is the tendency for storms to hover over one place for far longer than usual, thus dumping increasing amounts of rain on a smaller patch of the world. Scientists say warming is a contributing factor there, too. A jet stream of high winds six miles (nearly 10 kilometers) high helps determine the weather over Europe and is fed by temperature differences between the tropics and the Arctic.

Yet as Europe warms—with Scandinavia currently experiencing an unusual heat wave—the jet stream is weakened, causing its meandering course to stop, sometimes for days, Thiery said.

He said such a phenomenon was visible in Canada too, where it helped cause a “heat dome” in which temperatures rose to 50 C (122 F).

“And it is causing the heavy rain that we have seen in Western Europe,” he said.

  • A regional train sits in the flood waters at the local station in Kordel, Germany, Thursday July 15, 2021 after it was flooded by the high waters of the Kyll river. Credit: Sebastian Schmitt/dpa via AP
  • Rescue workers look down from a balcony as floodwaters run down a main street in Pepinster, Belgium, Thursday, July 15, 2021. Heavy rainfall is causing flooding in several provinces in Belgium with rain expected to last until Friday. Credit: AP Photo/Olivier Matthys
  • A woman walks up the stairs in her damaged house after flooding in Ensival, Vervier, Belgium, Friday July 16, 2021. Severe flooding in Germany and Belgium has turned streams and streets into raging torrents that have swept away cars and caused houses to collapse. Credit: AP Photo/Francisco Seco
  • A car floats in the Meuse River during heavy flooding in Liege, Belgium, Thursday, July 15, 2021. Heavy rainfall is causing flooding in several provinces in Belgium with rain expected to last until Friday. Credit: AP Photo/Valentin Bianchi
  • People carry their belongings past a broken road in Schuld, Germany, Friday, July 16, 2021. Two days before the Ahr river went over the banks after strong rain falls causing severals deaths and hundreds of people missing. Credit: AP Photo/Michael Probst
  • A man rows a boat down a residential street after flooding in Angleur, Province of Liege, Belgium, Friday July 16, 2021. Severe flooding in Germany and Belgium has turned streams and streets into raging torrents that have swept away cars and caused houses to collapse. Credit: AP Photo/Valentin Bianchi
  • Light posts along a pathway of the Meuse river as it rises during flooding in Liege, Belgium, Thursday, July 15, 2021. Heavy rainfall is causing flooding in several provinces in Belgium with rain expected to last until Friday. Credit: AP Photo/Valentin Bianchi

Even if greenhouse gas emissions are drastically curbed in the coming decades, the amount of carbon dioxide and other planet-heating gases already in the atmosphere means extreme weather is going to become more likely.

Experts say such phenomena will hit those areas that aren’t prepared for it particularly hard.

“We need to make our built environment—buildings, outdoor spaces, cities—more resilient to climate change,” said Lamia Messari-Becker, a professor of engineering at the University of Siegen.

Those that don’t adapt will risk greater loss of life and damage to property, said Ernst Rauch, chief climate and geoscientist at the reinsurance giant Munich Re.

“The events of today and yesterday or so give us a hint that we need to do better with respect to being ready for these these type of events,” he said. “The events themselves are not really unexpected, but the order of magnitude probably has surprised some.”



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Citation:
Experts: Europe floods shows need to curb emissions, adapt (2021, July 17)
retrieved 18 July 2021
from https://phys.org/news/2021-07-experts-europe-curb-emissions.html

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Hexbyte Glen Cove Ruined Belgian valleys mop up after devastating floods thumbnail

Hexbyte Glen Cove Ruined Belgian valleys mop up after devastating floods

Hexbyte Glen Cove

Flood waters in Belgium’s Brabant dislodged train tracks and caused a derailment.

When the water came, it came quickly. The clear-up operation in the devastated small towns of eastern Belgium will take far longer.

The densely-populated green valleys of the Meuse basin have been hit by what the country’s called a flood “without precedent”.

At least 20 people have been confirmed dead, and around the same number are reported missing. The survivors are in shock.

In Pepinster, the heart of the town was gouged by a torrent that left a trail of mud and flipped cars down the main street.

Part of the town was still inaccessible late Friday, a day after the surge. Helicopters circled overhead, lowering rescuers on a cable to check for survivors whenever a clue is spotted.

When Philippe, king of the Belgians, and Queen Mathilde visited on Friday, a day after the flood, stunned families were still digging out homes and saving what furniture they could.

Volunteer coordinator Roland Vanden Broek, 69, told the royals that the town need help from outside, but that local people had already risen to the challenge.

“The solidarity has been first rate. There was even a group of scouts that came to help out,” he told AFP.

Sylvianne Sioen, 52, lives next door to her 85-year-old mother, who has been in Pepinster for 71 years and has seen floods before, but never one that sent into her home, even into the drawers of her furniture.

“There is great solidarity. People I didn’t know came to help me carry my furniture out. It’s all to be thrown away,” Sioen told AFP.

Philippe, king of the Belgains and Queen Mathilde of Belgium (R) were among the well-wishers who visited the devastated town of Pepinster.

‘Lost everything’

One of the volunteers is 53-year-old Philippe Denbcyden, who brought his son ten kilometres (six miles) from Rechain to help his neighbours in Pepinster.

“We pile up the furniture on the pavement so that we can clean the houses. We also brought clothes. Some people here have lost everything,” he said.

At the railway station, a distribution centre has been set up for food and hot drinks. Neighbours queue in 20 centimetres of water, watching a man sink up to his waist as he tries to force open a door to a home.

Sioen’s sister-in-law Sylviane had the same problem when she returned home on Thursday after sleeping at her sister’s place because roads were closed. “There was a metre of water in front of the door,” she said.

Things have been very bad in neighbouring Germany too, but Pepinster, a small town outside Verviers, bore the brunt of the disaster within Belgium.

“It’s a disaster, a tsunami,” the local mayor, Philippe Godin, told AFP.

Austrian firefighters flew to Belgium to join the rescue effort after “unprecedented” floods.

There’s no electricity, no drinking water, unreliable mobile reception. Godin adds: “You have to think of the people who have lost everything, their memories. It’s terrifying.”

Back in Brussels, sodden after a week of torrential rain but safe from the floods, Prime Minister Alexander De Croo declared July 20 a day of national mourning.

“These are very exceptional circumstances, without any precedent in our country,” he said.

Interior Minister Annelies Verlinden said the death toll from the floods had risen to 20 people, with around 20 people missing. Earlier media reports had said 23 dead.

Devastation

Chaudfontaine, Theux, Verviers, Pepinster, Spa—dozens of cities, towns and villages have been hit.

Liege was threatened with evacuation of the town centre, but after splashing the top of its embankment, the Meuse failed to break its way into the city.

Cars were washed from roads and litter the river banks.

Cars lie in market squares, stacked up like damp firewood.

Scout camps were evacuated. A train derailed. Rescue helicopters and boats plucked up families and terrified pets and took them to safety.

Rescue teams have flown in from France, Italy and Austria to help the Belgian authorities.



© 2021 AFP

Citation:
Ruined Belgian valleys mop up after devastating floods (2021, July 16)
retrieved 17 July 2021
from https://phys.org/news/2021-07-belgian-valleys-mop-devastating.html

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part may be reproduced without the written permission. The content is provided for information purposes only.

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Hexbyte Glen Cove Climate change to bring more intense storms across Europe thumbnail

Hexbyte Glen Cove Climate change to bring more intense storms across Europe

Hexbyte Glen Cove

Credit: Pixabay/CC0 Public Domain

Climate change is driving a large increase in intense, slow-moving storms, a new study by Newcastle University and the Met Office has found.

Investigating how affects intense rainstorms across Europe, climate experts have shown there will be a significant future increase in the occurrence of slow-moving intense rainstorms. The scientists estimate that these slow-moving storms may be 14 times more frequent across land by the end of the century. It is these slow-moving storms that have the potential for very high precipitation accumulations, with devastating impacts, as we saw in Germany and Belgium.

Led by Dr. Abdullah Kahraman, of Newcastle University’s School of Engineering, the researchers used very detailed climate model simulations at the UK Met Office Hadley Centre. They found that slower storm movement acts to increase the amount of rainfall that accumulates locally, increasing the risk of flash floods across Europe beyond what has been expected based on previous studies.

Published in the journal Geophysical Research Letters, the study results show that storms producing intense rain may move slower with climate change, increasing the duration of exposure to these extremes.

Dr. Abdullah Kahraman, who is also a visiting scientist at the Met Office, said: “With recent advances in supercomputer power, we now have pan-European climate simulations resolving the atmosphere in high detail as short-range weather forecasting models do. These models have grid spacing of approximately 2 km, which allows them to simulate systems much better, resulting in better representation of extremes.

“Using these state-of-the-art climate simulations, we have developed metrics to extract potential cases for , and a smaller, almost-stationary subset of these cases with the potential for high rainfall accumulations. These metrics provide a holistic view of the problem, and help us understand which factors of the atmosphere contribute to heavy rainfall changes.

“This is one of the first studies to explore changes in the speed of such heavy rainfall systems—an important aspect contributing to flood risk. Currently, we are also investigating other extreme weather types by examining the climate simulations data with a severe weather forecaster’s perspective.”

Professor Hayley Fowler, of Newcastle University’s School of Engineering, added: “Governments across the world have been too slow in reducing and global warming continues apace. This study suggests that changes to extreme storms will be significant and cause an increase in the frequency of devastating flooding across Europe. This, alongside the current floods in Europe, is the wake-up call we need to produce improved emergency warning and management systems, as well as implementing climate change safety factors into our infrastructure designs to make them more robust to these severe weather events.”

Professor Lizzie Kendon, Science Fellow at the Met Office and Professor at Bristol University, said: “This study shows that in addition to the intensification of rainfall with global warming, we can also expect a big increase in slow-moving storms which have the potential for high rainfall accumulations. This is very relevant to the recent flooding seen in Germany and Belgium, which highlights the devastating impacts of slow-moving storms.

“Our finding that slow-moving intense rainstorms could be 14 times more frequent by the end of the century under the high emissions RCP8.5 scenario, shows the serious impacts that we may expect across Europe if we do not curb our emissions of greenhouse gases.”

The study findings are relevant to climate mitigation and adaptation policy in Europe, with specific implications for future flooding impacts, the design of infrastructure systems, and the management of water resources.

Currently, almost stationary intense rainstorms are uncommon in Europe and happen rarely over parts of the Mediterranean Sea. Accurate predictions of future changes in intense events are key to putting effective adaptation and mitigation plans in place to limit the adverse impacts of .



More information:
Abdullah Kahraman et al, Quasi‐Stationary Intense Rainstorms Spread Across Europe Under Climate Change, Geophysical Research Letters (2021). DOI: 10.1029/2020gl092361

Citation:

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Hexbyte Glen Cove Researchers surprised to find bacterial parasites behind rise of 'super bugs' thumbnail

Hexbyte Glen Cove Researchers surprised to find bacterial parasites behind rise of ‘super bugs’

Hexbyte Glen Cove

Credit: CC0 Public Domain

For the first time ever, researchers from the University of Pittsburgh School of Medicine discovered that phages—tiny viruses that attack bacteria—are key to initiating rapid bacterial evolution leading to the emergence of treatment-resistant “superbugs.” The findings were published today in Science Advances.

The researchers showed that, contrary to a dominant theory in the field of evolutionary microbiology, the process of adaptation and diversification in bacterial colonies doesn’t start from a homogenous clonal population. They were shocked to discover that the cause of much of the early adaptation wasn’t random point mutations. Instead, they found that phages, which we normally think of as bacterial parasites, are what gave the winning strains the early on.

“Essentially, a parasite became a weapon,” said senior author Vaughn Cooper, Ph.D., professor of microbiology and molecular genetics at Pitt. “Phages endowed the victors with the means of winning. What killed off more sensitive bugs gave the advantage to others.”

When it comes to bacteria, a careful observer can track evolution in the span of a few days. Because of how quickly bacteria grow, it only takes days for to acquire new traits or develop resistance to antimicrobial drugs.

The researchers liken the way bacterial infections present in the clinic to a movie played from the middle. Just as late-arriving moviegoers struggle to mentally reconstruct events that led to a scene unfolding in front of their eyes, physicians are forced to make treatment decisions based on a static snapshot of when a patient presents at a hospital. And just like at a movie theater, there is no way to rewind the film and check if their guess about the plot or the origin of the was right or wrong.

The new study shows that bacterial and evolution often go hand in hand, especially in the early stages of bacterial infection. This is a multilayered process in which phages and bacteria are joined in a chaotic dance, constantly interacting and co-evolving.

When the scientists tracked changes in genetic sequences of six bacterial strains in a skin wound infection in pigs, they found that jumping of phages from one bacterial host to another was rampant—even clones that didn’t gain an evolutionary advantage had phages incorporated in their genomes. Most clones had more than one phage integrated in their —often there were two, three or even four phages in one bug.

“It showed us just how much phages interact with one another and with new hosts,” said Cooper. “Characterizing diversity in early bacterial infections can allow us to reconstruct history and retrace complex paths of evolution to a clinical advantage. And, with growing interest in using phages to treat highly resistant infections, we are learning how to harness their potency for good.”



More information:
“Rampant prophage movement among transient competitors drives rapid adaptation during infection” Science Advances (2021). advances.sciencemag.org/lookup … .1126/sciadv.abh1489

Citation:
Researchers surprised to find bacterial parasites behind rise of ‘super bugs’ (2021, July 16)
retrieved 17 July 2021
from https://phys.org/news/2021-07-bacterial-parasites-super-bugs.html

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Types of Contact Lenses

melody huang medical reviewer
Medically Reviewed by
Dr. Melody Huang, O.D.
Alyssa Hill
Written by
Alyssa Hill
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The Basics: Different Types of Contact Lenses

There are many types of contact lenses available that correct vision problems (refractive errors). Some options include soft lenses, hard lenses, bifocal lenses, toric lenses, and multifocal lenses. The type of lens you need depends on what kind of refractive error you have. It is essential to consult with your doctor to determine the best option.

Common types of refractive errors include:

  • Astigmatism
  • Nearsightedness (myopia)
  • Age-related farsightedness (presbyopia)
  • Farsightedness (hyperopia)
  • A combination

Cost of Contact Lenses

Contact lenses cost anywhere between $150 to $1,500 per year. The cost depends on the patient’s insurance coverage, the brand of contacts, and the type of lenses they choose.

Vision Center Recommends 1800Contacts for all your contact needs. They provide the same contacts as your doctor, free shipping & returns, and 24/7 customer support. It’s simple to order online. Find Your Contacts Today

Soft Contact Lenses

Soft contact lenses are made of soft, flexible plastics (such as silicone hydrogel). The majority of soft lenses are “disposable,” as defined by the FDA, which means wearers must follow replacement schedules. Doing so decreases the risk of developing eye infections or “contact lens overwear syndrome.” Depending on the type of contact, the lenses are typically replaced daily, weekly, bi-weekly, or monthly.

Most people wear soft contact lenses, rather than hard lenses, because they are more comfortable. There are many types of soft contact lenses available. The most common ones include:

Daily Contacts

Daily wear contacts are only worn for one day. Most people wear daily disposable contacts after they wake up and throw them away before going to sleep. They should never be worn overnight. If you only wear contacts occasionally, daily contact lenses are a great option.

PROS
  • Safe and convenient. Daily contacts are convenient because wearers dispose of them each night. You also do not have to invest in contact cleaning solutions.
  • Better for your eye health. Reusable lenses can lead to eye infections, whereas daily contacts reduce the risk of diseases because you wear a fresh pair every day.
  • Reduce allergies. Dailies are also great for eye allergy sufferers since they reduce the potential for allergen build up on the lenses.
  • Cost-effective. You do not have to buy contact cleaning supplies for daily contacts, which can save money in the long-run. This is especially true if you do not wear contacts every day.
CONS
  • They can be expensive. Although convenient, daily contact lenses can be costly if you use more than one pair a day.

 

Weekly/Monthly Disposable Contact Lenses

Disposable lenses are replaced weekly, bi-weekly, or monthly. Disposable contact wearers also have to soak the lenses in contact solution every night. And, similar to daily disposable contacts, these lenses should never be worn overnight.

Daily disposable lenses can correct basic vision problems, including astigmatism and presbyopia (multifocal vision correction). However, if your prescription is outside of the range for daily disposable contacts, you may only be able to get weekly or monthly disposables.

PROS
  • Ideal for everyday use. Monthly disposable contacts are a great and cost-effective option for people who wear contacts every day or most days.
  • Cost-effective. These contacts are relatively inexpensive (compared to other types of lenses).
CONS
  • Less convenient than daily contacts and extended wear contacts. Unlike other types of soft lenses, disposable contacts have to be removed and soaked in contact solution nightly.
  • They are less sanitary than daily disposables. Weekly or monthly disposables are considered safe for use. However, monthly reusable contacts are less hygienic than daily disposable contacts.

 

Extended Wear Contact Lenses

Extended wear lenses are soft contacts that people wear overnight. Most types of extended wear lenses can be worn for up to six nights (seven days) without removal. However, some can last up to 30 days without removal. Eye doctors recommend resting your eyes for one full night without contact lenses after each scheduled removal.

PROS
  • Convenient. They do not have to be removed or replaced for up to a month.
  • They provide adequate oxygen flow through the eye. Soft extended-wear contacts are made of flexible plastic materials, which allow oxygen to flow through the cornea. Hard contact (rigid gas permeable) lenses cannot be worn overnight because they do not mold to your eye shape. Thus, less oxygen passes through the cornea, which can lead to serious eye problems (e.g., blurred vision) over time.
  • Cost-effective. A 12-month supply of extended wear lenses will cost anywhere between $250 and $300.
CONS
  • Eye infection risks. Extended wear contact lens wearers have a higher chance of developing eye infections. This is because bacteria and other potentially harmful microorganisms can get trapped between your eye and the lens. Severe and untreated eye infections can lead to blindness.

 

The oxygen flow of a contact lens depends on the type of material, as opposed to the flexibility of the lens. Extended-wear contacts are typically silicone hydrogel, which is the most breathable soft contact lens material. Modern RGP (rigid gas permeable) lenses are much more breathable than traditional hard lenses. In some cases, they allow just as much oxygen as soft contacts.

Extended wear contacts do not support every lens type. It is essential to get an exam so your eye care provider can determine your tolerance to overnight contacts.

Hard Contact Lenses

Most rigid lenses, also known as hard contact lenses, are made of gas-permeable materials. The two most well-known types of hard lenses include PMMA (conventional) lenses and RGP lenses.

The main difference between these lenses is that RGP contacts allow oxygen to flow through the cornea. They are also more comfortable than PMMA contacts. PMMA lenses reduce the flow of oxygen to the cornea, leading to eye problems over time.

Rigid Gas-Permeable Lenses (RGP)

Rigid gas-permeable (RGP) lenses are a type of hard contact. They are more expensive than convention hard lenses (PMMA). Some RGP lenses can be worn overnight and only need to be replaced every 2 to 3 years. However, most eye doctors do not recommend wearing them for an extended period or during sleep.

RGP contact lenses are especially useful for astigmatism (blurred vision due to an eye curvature imperfection) or keratoconus (a bulging cornea).

PROS
  • Retain shape. RGP lenses mold to your eye and retain shape when blinking because they consist of a firm plastic material.
  • Sharper vision. These lenses provide sharper vision than soft lenses.
  • Durability. GP lenses are very durable but slightly less durable than PMMA hard lenses.
  • Oxygen flow. They offer better oxygen flow to the cornea than other types of hard lenses.
CONS
  • Comfortability. They are less comfortable than soft lenses.
  • Price. RGP’s are more expensive than other types of hard contact lenses.

 

PMMA Lenses

Conventional contact lenses, also called PMMA lenses, were the first type of hard lens ever made. They consist of a material called polymethylmethacrylate (PMMA), which is a stiff and plexiglass-type plastic. For many people, the wear time of PMMA lenses is between 8 to 16 hours.

PMMA lenses have excellent optics but do not provide enough oxygen to the eye. For this reason, most people do not use hard lenses and opt for soft lenses instead.

PROS
  • Maintenance. They are easy to maintain and take care of.
  • Inexpensive. They are durable and less expensive than other types of contact lenses.
  • Extra eye safety. PMMA provides extra eye safety (minimal risk to the eyes) because the material is thick.
  • Relative rigidity. They have relative stiffness (where flexing may be a problem).
CONS
  • Oxygen flow. They interfere with the flow of oxygen through the cornea.
  • Discomfort. PMMA lens materials do not mold to the shape of your eye. They are also the least comfortable type of contact lens. People who wear them are more prone to developing “contact lens overwear syndrome.”
  • Spectacle blur. People who wear PMMA lenses are more susceptible to “spectacle blur.” This condition is when someone’s eyesight becomes blurry after they take their contacts out and put glasses on.

 

Other Types of Contact Lenses

In some cases, eye care professionals may recommend customized lenses, depending on the patient’s eye shape and prescription. Other, less common, types of contact lenses include:

Bifocal Contact Lenses

Bifocal contact lenses have two different prescriptions in the same lens. They work similarly to bifocal glasses. One prescription is for normal, distance vision, and the other is for close-up reading. These types of contacts have been around for many years, but have been rising in popularity recently.

Multifocal Lenses (Presbyopia)

Presbyopia, also called age-related farsightedness, reduces the ability to focus up close as you get older. Eye doctors may recommend multifocal lenses to patients with presbyopia, especially if they do not want to wear two pairs of prescription glasses.

Toric Contact Lenses

Toric contact lenses are customized lenses that correct astigmatism. Astigmatism is a common refractive error caused by an imperfection in the curvature of the cornea (eye lens).

Bandage Lenses

Bandage contact lenses protect diseased or injured corneas from blinking and rubbing of the eyelids. They allow the corneas to heal and reduce discomfort. Bandage lenses typically consist of soft contact materials.

Vision Center Recommends 1800Contacts

1800Contacts has a huge selection of contact lenses and award-winning 24/7 customer service.

Author: Alyssa Hill  | UPDATED June 23, 2021

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Medical reviewer: Dr. Melody Huang, O.D.

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