The lens, with a spiral configuration, excels in diverse lighting and maintains multifocality regardless of pupil size, unlike current multifocal lens.
New lens with spiral surface maintains clear focus across distances in changing light.
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A significant advancement in lens technology has been achieved by developing a spiral-shaped lens capable of maintaining clear focus across different distances and under varying light conditions.
Unlike conventional progressive lenses, which often suffer from distortions, this innovative lens, called the spiral diopter, functions flawlessly, similar to how progressive lenses correct vision, according to researchers at Photonics, Numerical and Nanosciences Laboratory (LP2N).
Its distinctive spiraling design creates numerous focal points, akin to combining multiple lenses. This unique arrangement enables clear vision at different distances.
The team claims its potential applications span various fields, including enhancing contact lens technologies, improving intraocular implants for cataracts, and advancing miniaturized imaging systems.
Asteroid impacts at key moments in the Earth’s past could have set off global freezes that covered the entire planet in ice for thousands or even millions of years.
This is the conclusion of a study led by researchers at Yale University, who modeled the climatic consequences of a large asteroid strike at four points in our planet’s past in a study published in the journal Science Advances.
An asteroid impact would eject a considerable amount of material into the Earth’s atmosphere, blocking out the sun’s rays and leading to cooling as a result. The team found that, in an already suitably cold climate, this effect could tip the Earth system into runaway cooling, leading to what scientists have dubbed a “Snowball Earth.”
However, experts not involved in the study told Newsweek that, at present, there is no evidence to suggest that any asteroids did strike Earth around the times in the past when such global glaciations are known to have occurred.
Thanks to their modeling, climate scientists have known since the late sixties that if the Earth were to get sufficiently cold, it would create a positive feedback loop leading to runaway cooling until the entire planet was covered in ice.
This “Snowball Earth” outcome begins with the ice sheets spreading out further from the poles. As ice is more reflective than water or land, this would increase the amount of sunlight cast back into space, leading to further cooling.
This, in turn, leads to the formation of more ice, colder temperatures, and so forth—a cascade that would only stop when the entire planet was completely covered in ice and had entered into a new equilibrium state.
Based on the projected distributions of glacial sediments, alongside other evidence, scientists believe that Earth has entered a “snowball” state at least twice in the past, at points between 720 and 635 million years ago.
Exactly what set off these episodes of runaway cooling, however, has been a subject of considerable debate.
The conventional hypothesis, however, has been that the level of Earth-warming greenhouse gasses somehow decreased to such a point that the “snowballing” process began.
An artist’s impression of a Snowball Earth. Scientists believe Earth has experienced at least two such episodes in its history.NASA
“We decided to explore an alternative possibility,” said paper author and climate dynamicist Minmin Fu of Yale University in a statement.
“What if an extraterrestrial impact caused this climate change transition very abruptly?”
In their study, Fu and his colleagues made use of the same kind of model that is employed to predict future climate scenarios. Such models can simulate both atmospheric and ocean circulation, as well as the formation of sea ice, under different scenarios.
The team explored the aftermath of a hypothetical large asteroid collision—equivalent in size to the dinosaur-killing Chicxulub impactor—during four quite different periods in the Earth’s past.
These included the Neoproterozoic Era (1 billion–542 million years ago); the Cretaceous Period (145–66 million years), the Last Glacial Maximum (21,000 years ago, when ice sheets covered much of Northern America, Northern Europe and Asia), and the pre-industrial period (more than 150 years ago).
The researchers determined that in the two warmer periods they examined—the pre-industrial and Cretaceous Periods—it is unlikely that an asteroid impact would have been able to trigger a “Snowball Earth” condition.
The picture appeared very different, however, when they considered an impact scenario in the Neoproterozoic, or at the Last Glacial Maximum.
During these periods in Earth’s history, the team explained, global temperatures may have been cold enough to warrant calling them an ice age.
The effects of an asteroid impact during these chilly periods, they added, may have pushed the Earth over a climate tipping point and into a global glaciation.
File photo of sea ice. Climate modeling has shown that a sufficient spread of sea ice from the poles can result in a runaway cooling effect.
The modeling indicated that an asteroid-triggered shift to a frozen Earth would have been relatively rapid.
“What surprised me most in our results is that, given sufficiently cold initial climate conditions, a ‘Snowball’ state after an asteroid impact can develop over the global ocean in a matter of just one decade,” said paper co-author and Yale climate scientist professor Alexey Fedorov.
“By then, the thickness of sea ice at the Equator would reach about 10 meters [33 feet],” he added.
“This should be compared to a typical sea ice thickness of one-to-three meters [around 3–10 feet] in the modern Arctic.”
Professor Ian Fairchild, a geoscientist with the University of Birmingham, England, who was not involved in the present study, told Newsweek that the work is an interesting theoretical study.
However, Fairchild said, “there is a lack of observational evidence in the geological record for such an impact.”
He explained: “The onset of the earlier Snowball glaciation around 716 million years ago appears too gradual for such a mechanism to have operated.”
Artist’s impression of an asteroid impact. Scientists modeled the effect on the climate of an asteroid the size of the one that brought about the extinction of the dinosaurs.
“Bold hypotheses like this serve a valuable purpose in stimulating discussion,” said Professor Thomas Gernon, a geologist at the University of Southampton, England, who was also not involved in the present study.
He told Newsweek: “But as [astronomer] Carl Sagan said, ‘Extraordinary claims require extraordinary evidence’—and where this hypothesis currently falls down is in the lack of geological evidence for such a huge impact at this critical time in Earth history.”
Scientists are not aware of any impact craters preserved on Earth that match up with the timings of Earth’s previous “snowball” episodes, Gernon said.
“In summary, I remain open-minded but skeptical,” he said, concluding: “Time will tell whether there is a whiff of space rock in the critical geological sections.”
In their paper, Fu and colleagues suggest that a hypothetical impact crater preceding past global glaciations might have been destroyed by either erosion, burial, or subduction of the corresponding crust back into the Earth’s mantle.
On the risk of a global glaciation in our future should Earth be struck by an asteroid, the researchers believe that such an outcome would be unlikely.
The reason, they explained, is that global temperatures were already too warm for a “Snowball Earth” outcome in the pre-industrial period, and we have since increased temperatures even further through the emission of greenhouse gasses.
That said, depending on the size of the impactor, the other consequences of such an impact—which, alongside blotting out the sun, might include fires, tsunamis, and acid rain—could be just as devastating, the team said.
Monarch populations are teetering on extinction, their numbers down to 5% of what they were a few decades ago. Here’s what to know and the simplest way to help.
Decades ago, monarch butterflies were so plentiful that the sound emanating from overwintering groves filled with the brightly coloured insects flapping their wings was described by observers as being akin to a gentle summer rain or a rippling stream. In some cases, tree branches would even collapse under the weight of clusters of monarchs. But recent overwintering counts of the western and eastern migrating monarchs conducted in California and Mexico make clear that gatherings of that magnitude are part of a bygone era.
In the forests of central Mexico, where eastern monarch butterflies have long wintered, the species were estimated to occupy a mere 0.9 hectares (2.2 acres) during the 2023-2024 winter season. That’s 59% less than one year earlier, when the butterflies occupied 2.2 hectares (5.5 acres) – according to the results of an annual survey released this week by the World Wildlife Fund and its partners.
The 2023-2024 winter figures not only represent the second-worst year ever recorded for the butterflies in central Mexico since monitoring began in 1993, but the report is also considered a benchmark for the overall health of the species. There has been a largely downward trend in the fortunes of the eastern monarch since 1996-1997, when the butterflies took over 18 hectares (45 acres) of central Mexican forest.
The report follows the release of the 27th annual western monarch count conducted by Oregon-based Xerces Society for Invertebrate Conservation. The tallies of that effort, which is focused on the overwintering monarch population throughout coastal California, found slightly more than 230,000 butterflies across 256 sites. Here, too, the figures represent a drop from 2023 when the population was around 300,000. Perhaps more importantly, the latest western monarch population amounts to just 5% of what it was in the 1980s, when they were estimated to be found in their millions.
“This is absolutely concerning, but perhaps not surprising,” says Deborah Landau, director of ecological management for the global environmental non-profit The Nature Conservancy, “There are so many factors now adding stress to the monarch population.”
The hopeful news, according to Landau and others involved in studying monarch populations, is that people increasingly appear to understand the importance of pollinators such as monarchs. What’s more, there are a few key steps individuals can take to help save monarchs around the globe.
Monarch butterfly populations are declining, but humans can do one easy thing to help.
The forces driving monarch decline
Two distinct populations, the eastern and western monarchs, are being impacted by the same set of threats: habitat destruction, pesticide exposure and extreme weather brought about by climate change.
When it comes to habitat, there are very few measures in place to stop development of areas critical to butterflies, says Emma Pelton, senior endangered species conservation biologist and western monarch lead for the Xerces Society.
“We do not have comprehensive legal protection for their overwintering sites,” Pelton explains. “Legal protection could help prevent the cutting down of groves of trees that they need.”
In both Mexico and California, a big part of the problem is deforestation driven by logging, urban development and the demand for agricultural land.
Proliferating use of pesticides has also been devastating for monarchs. A report from the Endangered Species Coalition identifies monarchs as one of 10 species imperiled by pesticides, including insecticides, herbicides and rodenticides that are used on crops, commercial and industrial developments, as well as homes and lawns. Some popular herbicides used to target weeds in domestic gardens also kill milkweed, which monarchs depend upon not only as a food source, but to also lay their eggs.
“There are so many more pesticides in use today than historically,” says Landau. “And cumulatively, it’s impacting the monarchs more and more.”
Finally, there are increasingly frequent extreme weather events triggered by climate change, which has also been detrimental to the fragile butterflies. Fluctuations in temperature caused by climate change disrupt and impact the monarch butterfly’s life cycle. At overwintering sites in particular, cold temperatures may cause a switch in the direction of the migration from southward to northward, for instance.
Temperature also impacts the food sources available to monarchs. “These insects are very closely tied to the natural cycles of plants that bloom at certain times and are very dependent on this,” says Landau. “If the plants leaf out or flowers bloom too early, then the monarchs might arrive too late to take advantage of their nectar or leaves. But the opposite is also true, if the monarchs fly early because it’s warm, then they may arrive before the plants are ready to serve as a food source for them.”
Extreme rain events like those California recently experienced can also have a devastating effect, especially if it coincides with colder temperatures in overwintering areas. Monarchs have a hard time surviving such conditions for very long.
“I definitely think climate change could be the straw that broke the camel’s back for monarchs when combined with the problems of habitat loss and pesticide use,” says Pelton.
Ranger Timothy Puopolo releases about 125 monarch butterflies in Kingsley Park.
How to help save monarchs
Despite all the challenges they face, there is hope for the monarchs. Their extinction is not a foregone conclusion, Pelton and other experts say. There is still much that can be done to help shape the monarch’s future.
There is hope, for instance, in the fact that the general public has begun to realise how critical it is to incorporate plants into landscapes and gardens that support monarchs.
Monarch caterpillars are 100% reliant upon milkweed for food. The plants also serve as a host for monarch eggs. And because milkweed plants are inexpensive to purchase and don’t require a great deal of space, they offer an accessible way for the general public to help the butterflies survive.
“Even if you have a postage-stamp-size backyard, every little bit counts,” says Landau, who stresses that using native milkweed is key.
“Sometimes people plant non-native, like tropical milkweed that has a longer growing season, which can disrupt the monarch’s migration pattern because they might not leave when they are supposed to,” she explains.
Non-native milkweed is also more susceptible to a parasite that’s harmful to monarchs, she adds.
Planting nectar-rich flowers and plants is also critical to a monarch’s survival. Like milkweed, these should be native to your area. In California, some of the native options include Yarrow, Sunflowers, Coyote Mint, sunflowers and goldenrod.
“Nectar plants that adult monarchs eat are equally important because if they don’t have that food source, they’re not going to have the energy to make that migration,” says Kelly Bills, executive director of the non-profit Pollinator Partnership, which focuses its efforts on supporting the preservation of all pollinators.
For those where planting is not an option, downloading the Monarch Watch app is another way to help. The app is a community science effort that allows users to contribute data about where and when monarchs are being spotted using geotagging.
All three experts also suggest one last, perhaps less obvious way to help monarchs in the longer term: reducing carbon emissions.
“We know that climate change is driving much of this decline for monarchs and other pollinators, so you can still do your part by taking into consideration – and reducing – the impact of carbon in your daily life,” says Bills.
Once they enter the body, drugs, apart from carrying out their therapeutic function, are biochemically transformed by the action of the metabolic machinery, a process that facilitates their expulsion. This biotransformation results in a gradual disappearance of the drug, which is converted into its metabolites.
These, in turn, can reach high concentrations in the body and also show a biological activity that may be different from that of the original drug. That is, the metabolites and the drug coexist in the body and can cause effects different from those obtained with the individual molecules.
This is the case of Rucaparib, a drug used in chemotherapy for ovarian cancer, breast cancer, and, more recently, prostate cancer, and its metabolite, the M324 molecule. Rucaparib is part of a group of drugs designed to treat several types of cancers that show alterations in DNA repair. Specifically, they are inhibitors of the PARP1 enzyme, involved precisely in the process of repairing mutations in the genetic material.
A study led by researchers Albert A. Antolin, from the Oncobell program of the Bellvitge Biomedical Research Institute (IDIBELL) and ProCure of the Catalan Institute of Oncology (ICO), and Amadeu Llebaria, from the Institute of Advanced Chemistry of Catalonia (IQAC-CSIC ), has shown that Rucaparib and its main metabolite M324 exhibit differential activities.
Published in the journal Cell Chemical Biology, the paper has analyzed Rucaparib and M324, making a computational prediction of the metabolite’s activity. The article describes the synthesis of M324 and its biological assay, demonstrating that the drug and its metabolite have differentiated activities and act synergistically in some prostate cancer cell lines.
Surprisingly, M324 reduces the accumulation of the protein α-synuclein (an important component of Lewy bodies) in neurons derived from patients with Parkinson’s, a neurodegenerative disease characterized by a movement disorder, and in which neurons do not produce sufficient amounts of the neurotransmitter dopamine.
Specifically, the synergy demonstrated between Rucaparib and M324 in prostate cancer cell lines could have an impact on clinical trials for advanced stages of this type of cancer. On the other hand, the fact that M324 is capable of reducing the abnormal accumulation of α-synuclein in neurons derived from stem cells of a Parkinson’s patient highlights the therapeutic potential of this metabolite and its possible pharmacological application for the treatment of this neurodegenerative disease.
These results have been obtained thanks to the collaboration of the IDIBELL and ICO groups led by Miquel Àngel Pujana and Álvaro Aytés, and the group of Antonella Consiglio, from IDIBELL and the UB.
Researchers have used computational and experimental methods to characterize comprehensively, and for the first time, the pharmacology of the M324 molecule. The first author of the work, Huabin Hu, has made an exhaustive prediction of the differential activity of the original drug and its product, which translates into different spectra of the phosphorylation pattern of cellular proteins.
Carme Serra, from the MCS group at IQAC-CSIC, has synthesized the metabolite M324, which has allowed experimental verification of the computational prediction in biological and cellular assays. The results obtained could have implications for clinical treatment with Rucaparib and, in turn, open new opportunities for drug discovery.
In summary, the study points towards a new conceptual perspective in pharmacology: one that considers drug metabolism not as an undesirable process that degrades and eliminates the therapeutic molecule from the body but rather as one that can have potential advantages from a therapeutic point of view. Indeed, the work highlights the importance of characterizing the activity of drug metabolites to comprehensively understand their clinical response and apply it in precision medicine.
People over 65 make up a sizable portion of Americans on GLP-1 drugs. That might be trouble.
Imagine an older man goes in to see his doctor. He’s 72 years old and moderately overweight: 5-foot-10, 190 pounds. His blood tests show high levels of triglycerides. Given his BMI—27.3—the man qualifies for taking semaglutide or tirzepatide, two of the wildly popular injectable drugs for diabetes and obesity that have produced dramatic weight loss in clinical trials. So he asks for a prescription, because his 50th college reunion is approaching and he’d like to get back to his freshman-year weight.
He certainly could use these drugs to lose weight, says Thomas Wadden, a clinical psychologist and obesity researcher at the University of Pennsylvania, who recently laid out this hypothetical in an academic paper. But should he? And what about the tens of millions of Americans 65 and older who aren’t simply trying to slim down for a cocktail party, but live with diagnosable obesity? Should they be on Wegovy or Zepbound?
Already, seniors make up 26.6 percent of the people who have been prescribed these and other GLP-1 agonists, including Ozempic, since 2018, according to a report from Truveta, which draws data from a large network of health-care systems. In the coming years, that proportion could rise even higher: The bipartisan Treat and Reduce Obesity Act, introduced in Congress last July, would allow Medicare to cover drug treatments for obesity among its roughly 50 million Part D enrollees above the age of 65; in principle, about two-fifths of that number would qualify as patients. Even if this law doesn’t pass (and it’s been introduced half a dozen times since 2012), America’s retirees will continue to be prescribed these drugs for diabetes in enormous numbers, and they’ll be losing weight on them as well. One way or another, the Boomers will be giving shape to our Ozempic Age.
Certain groups saw a significant decrease in numbers.
Weight loss drug tirzepatide is linked with a drop in blood pressure in a new study.
Researchers found a substantial reduction within 36 weeks on the medication.
Doctors say this could be linked to weight loss or something else entirely.
Medications like semaglutide and tirzepatide have made headlines for months for their role in helping people with obesity lose a significant amount of weight. But research is consistently finding additional benefits of going on these medications. Now, there’s a new one to add to the list: They may help lower blood pressure.
That’s the major finding from a new study published in the American Heart Association’s journal, Hypertension. For the study, researchers analyzed data from 600 people who participated in the SURMOUNT-1 weight loss study to see if there was an impact on blood pressure in people who took tirzepatide, which was approved by the U.S. Food and Drug Administration (FDA) for weight loss in November under the name, Zepbound.
Study participants either received a placebo or a tirzepatide dose of 5 milligrams, 10 milligrams, or 15 milligrams. About 1/3 of study participants had high blood pressure (a.k.a. hypertension) at the start of the study and were taking one or more medications for it.
After 36 weeks, researchers found that study participants in all of the tirzepatide groups had lowered blood pressure by the end, with the biggest reduction in systolic blood pressure (the top number in a reading) being 10.6 mmHg in the 10 milligram group.
The researchers also found that people on tirzepatide had lowered blood pressure when they did measurements during the day and at night. Here’s what doctors want you to know about the findings. (Note: Prevention no longer uses the Body Mass Index (BMI) as a measurement of health.)
Why might weight loss drugs help lower blood pressure?
Doctors agree that a lot of this is likely due to weight loss. “Typically, the greater the degree of weight loss, the greater the degree of blood pressure decrease,” says Colleen Tewksbury, Ph.D., M.P.H., R.D., a registered dietitian and associate professor at Penn Medicine. “It may not be the medication by itself.”
In this particular study, patients who took tirzepatide lost up to 20.9% of their body weight compared to those who took a placebo.
“The findings are impressive, although not unexpected given the critical role that weight gain plays in causing hypertension in the first place,” says Christoph Buettner, M.D., Ph.D., chief of the division of endocrinology at Rutgers Robert Wood Johnson Medical School. Since high blood pressure is often linked to having obesity or overweight, lowering a person’s body fat should reduce their blood pressure, he says.
In fact, weight loss can be so effective for lowering blood pressure, that patients on blood pressure medicines should check in with their doctor regularly if they’re losing weight, says Mir Ali, M.D., a bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA. “Their blood pressure medications will likely need to be adjusted,” he says.
But it’s also possible that tirzepatide itself impacts blood pressure, says Sahil Parikh, M.D., director of endovascular services at NewYork-Presbyterian/Columbia University Irving Medical Center. “It remains unclear if the blood pressure reduction is benefitting from the drug having a direct effect on blood pressure, as opposed to the indirect impact on blood pressure through weight loss alone,” he says.
The study focused on tirzepatide, but Dr. Buettner says that fellow weight loss drug semaglutide “has similar effects” when it comes to impact on blood pressure.
While high blood pressure is linked to serious health conditions like heart attack, stroke, and heart failure, “we will need long-term trial results” to see if weight-loss medications can reduce those risks, too, says Laxmi Mehta, M.D., a non-invasive cardiologist at The Ohio State University Wexner Medical Center.
How tirzepatide works
Tirzepatide is a medication that’s used to help manage type 2 diabetes (under the name Mounjaro) and for weight loss (under the name Zepbound). It’s an injectable medication that’s taken once a week to help with weight loss in people who have obesity or overweight.
The medication specifically targets glucagon-like peptide 1 (GLP-1) agonists, which encourage the body to produce more insulin (a hormone that escorts blood sugar to cells, where they’re used for energy) when blood sugars start to rise, along with something called glucose-dependent insulinotropic polypeptide (GIP) receptors, Dr. Ali explains.
Zepbound can also make you feel fuller longer, as well as reduce cravings, causing people to feel less hungry than usual on the medication.
Natural ways to lower blood pressure
If you’re concerned about your blood pressure, doctors say there are a few things you can do:
Be active. “Exercise is critical to heart health, and it is one of the best ways that you can lower your blood pressure naturally,” says Nicole Weinberg, M.D., a cardiologist at Providence Saint John’s Health Center in Santa Monica, CA.
Ask your doctor if you should try to lose weight. “For every 10 pounds of weight loss, you can expect a significant blood pressure drop,” Dr. Weinberg says.
Rethink your diet. Dr. Buettner recommends following a heart-healthy diet rich in fruits, vegetables, whole grains, lean proteins, and low-fat dairy.
Limit alcohol. “If you drink alcohol, do so in moderation,” Dr. Buettner says.
Try to manage your stress levels. That can include doing things like deep breathing, meditation, yoga, or things that relax you, Dr. Buettner says.
It’s also important to stay on top of your blood pressure, even if you do everything else right, Dr. Parikh says. “As we age, there is a tendency for blood pressure to go up, and in time, medication may be critical,” he says.
As of right now, there’s nothing to suggest that weight loss drugs will lower your blood pressure if you don’t have overweight or obesity, Tewksbury says. But if you’re concerned about your blood pressure levels, check in with your doctor. They should be able to offer personalized advice.
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