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Eingereichte Übersetzungsbeispiele: 23
Englisch > Chinesisch: Coffee drinker and liver disease General field: Medizin Detailed field: Lebensmittel
Ausgangstext - Englisch New research from the United Kingdom has found that drinking coffee is associated with a lowered risk of chronic liver disease and other liver health conditions.
The study, which published in the journal BMC Public Health on June 22, found that coffee drinkers had a 21 percent reduced risk of liver disease and a 49 percent lower risk of death from chronic liver disease.
The health benefits appeared to plateau around four cups of coffee a day and were most pronounced in people who drank ground coffee than those who drank instant coffee.
This study adds to the growing evidence that coffee appears to benefit liver health.
Researchers are still learning how coffee might fight liver disease, but they suspect it’s because the popular beverage has anti-inflammatory or anti-fibrotic properties.
The researchers evaluated the health data of 495,585 people who were tracked for an average of 10 years.
Of the group, 78 percent consumed either caffeinated ground coffee, instant coffee, or decaffeinated coffee, and 22 percent consumed no coffee.
Throughout the study, there were 3,600 cases of chronic liver disease or steatosis, a buildup of fat in the liver.
There were also 184 cases of hepatocellular carcinoma, a liver cancer.
The coffee drinkers in the study had a 21 percent reduced risk of developing chronic liver disease and a 20 percent lower risk of fatty liver disease.
According to the researchers, ground coffee contains the highest levels of kahweol and cafestol — two ingredients thought to protect against liver disease.
Englisch > Chinesisch: Elemental iron in brain tissue General field: Naturwissenschaften Detailed field: Medizin (allgemein)
Ausgangstext - Englisch For the first time, scientists have found tiny deposits of elemental, uncharged iron and copper in human tissue.
An international team of researchers discovered the metals in postmortem brain samples from two individuals who had Alzheimer’s disease.
Metal ions, which are metal atoms with a net positive charge after losing one or more electrons, are essential components of many enzymes that catalyze chemical reactions in cells.
These positive ions can strip the electrons from other molecules, oxidizing these molecules.
However, the deposits of copper and iron that the scientists identified in the brain tissue of people with Alzheimer’s were in their elemental, uncharged form.
These are highly reactive metal atoms that, under normal circumstances, would rapidly undergo oxidation to form more chemically stable ions.
Previously, scientists have only identified elemental metals such as these in microorganisms, viruses, and plants.
The researchers found the metals within beta-amyloid plaques, which are the clumps of protein that are a hallmark of Alzheimer’s disease.
Previous research has linked changes in the metabolism of copper and iron in brain tissue to neurodegenerative diseases, including the formation of amyloid plaques in Alzheimer’s disease.
The tiny deposits of elemental iron that the team found in the new study were magnetic, so in principle, doctors could use them for diagnosis or as a marker of disease progression.
Synchrotrons accelerate electrons to almost light speed, generating brilliant beams of light that can probe the atomic structure of matter.
The deposits of elemental iron and copper that the scientists identified were on the nanoscale, meaning that they were approximately 10,000 times smaller than a pinhead.
Englisch > Chinesisch: Ultra-processed food and health General field: Medizin Detailed field: Medizin: Gesundheitswesen
Ausgangstext - Englisch Children as young as 7 years old who eat large amounts of ultra-processed food experience steady weight gain into adulthood, leading many to be categorized as having obesity.
An analysis published this week in JAMA Pediatrics looked at more than 9,000 children in Britain whose daily diets were about 70 percent ultra-processed, described as high-calorie foods with various artificial ingredients.
High-processed foods are made primarily from substances extracted from food, including fats, starches, and sugars. Typically, those products include fast food, soft drinks, frozen meals, candy, and salty snacks.
Until 24 years old, the subjects in the “high consumption” category saw an average extra weight gain of about a half-pound and more than a half-inch waist circumference per year over the 10-year study period.
Those consuming high amounts of ultra-processed foods face a greater chance of not only obesity but related issues, including diabetes, heart disease, heart attack, and stroke.
“The increasing availability and variety of ultra-processed foods have reshaped global food systems by displacing dietary patterns previously based on fresh and minimally processed foods,” the researchers from the Imperial College of London said in a statement.
“Of particular concern is the growing consumption of these foods among children and adolescents, who are leading consumers,” they added.
“Ultra-processed foods are one of the worst offenders to health,” Tierney said. “They negatively affect metabolism at a cellular level, damaging the functions and abilities of cells. It’s like a vicious cycle because processed foods cause things like atherosclerosis, insulin resistance, and weak mitochondria, which in turn cause fatigue, foggy brains, mood disorders, decreased productivity, and more.”
Englisch > Chinesisch: Stress and mPFC General field: Medizin Detailed field: Medizin: Gesundheitswesen
Ausgangstext - Englisch Experiencing stress over a prolonged period, such as during the pandemic, is associated with the development of depression. One of the major symptoms of depression includes anhedonia, or the inability to anticipate or feel pleasure.
However, researchers do not have a comprehensive understanding of how chronic stress leads to depression or the accompanying symptoms of anhedonia.
Evidence suggests that the medial prefrontal cortex (mPFC), a brain region involved in processing reward and regulating the stress response, may be involved in mediating these effects of chronic stress.
While the mPFC is involved in regulating the stress response, acute and chronic stress also elicit changes in the mPFC.
Studies in rodents have shown that glutamate, an excitatory neurotransmitter, is released by neurons in the mPFC during acute stress.
However, rodents exposed to chronic stress exhibit lower levels of glutamate release in the mPFC when faced with a new acute stressful event.
Scientists think that such a reduction in the mPFC glutamate response due to chronic stress could be a protective adaptation to stress.
To investigate the role of the mPFC in depression, the researchers recruited 65 individuals without depression and 23 people with MDD who were not taking medication.
Around 11–12 days before the experiment, the researchers used the Perceived Stress Scale (PSS) to measure each participant’s subjective or perceived stress levels over the past month.
On the test day, the participants completed a task that induced acute stress. The researchers used magnetic resonance spectroscopy (MRS), a noninvasive imaging technique, to measure changes in glutamate levels in the mPFC before and after the acute stress test.
Englisch > Chinesisch: Sleep pattern and mental health General field: Medizin Detailed field: Medizin: Gesundheitswesen
Ausgangstext - Englisch For some people, mornings are a time of productivity and alertness. However, others prefer to sleep later and get their best work done in the afternoon and evening.
Unfortunately for the later risers among us, the workplace tends to be more geared toward a 9-to-5 day, which forces night owls to wake up much earlier than they’d like.
The research indicates that when people’s sleep patterns are out of sync with their body clock, they may be at increased risk for depression and anxiety. They may also report lowered feelings of well-being.
In addition, there appears to be a genetic link between wake time and depression risk.
The researchers based their work on previous research that had already mapped out 351 genes associated with either being an early riser or a night owl.
They then used a type of statistical analysis called Mendelian randomization to look at whether these genes were causally associated with seven mental health and well-being outcomes, such as major depression.
Data from more than 450,000 adults from the U.K. Biobank’s biomedical database was used in the analysis.
The data included genetic information as well as each person’s assessment about whether they felt they were a morning person or an evening person.
After analyzing the data, the team found that people who were more out of alignment with their natural body rhythm were more likely to report lower well-being and more feelings of depression and anxiety.
In addition, they found evidence that if a person’s genes have programmed them to be an early riser, this may help to protect them from depression, possibly because they would be in more alignment with society’s expectations as well as their natural circadian rhythm.
Ausgangstext - Englisch Drug-induced hepatitis is a redness and swelling (inflammation) of the liver that is caused by a harmful (toxic) amount of certain medicines.
The liver helps to break down certain medicines in your blood. If there is too much medicine in your blood for your liver to break down, your liver can become badly damaged. This can lead to drug-induced hepatitis.
Drug-induced hepatitis is rare. It is caused when you have a harmful or toxic amount of some medicines, vitamins, herbal remedies, or food supplements.
In most cases, you may be taking a medicine for several months before it reaches a toxic level and affects your liver. But the disease can also happen if you take too much of some medicines, such as acetaminophen. In this case, it can happen quickly. Other times it is an allergic reaction.
Many types of medicines may cause drug-induced hepatitis. These include:
Pain and fever medicines that have acetaminophen
Aspirin and over-the-counter pain and fever medicines (NSAIDs or nonsteroidal anti-inflammatory medicines)
Anabolic steroids, man-made medicines that are like the male sex hormone testosterone
Some medicines used to treat bacterial infections (antibiotics)
Birth control pills (oral contraceptives)
Statins, used to lower cholesterol
Sulfa medicines, a type of antibiotic
epileptic
Herbal medicines, including ephedra, Germander, Pennyroyal, and many others. Keep in mind that not all "natural" or "herbal" supplements are safe. They are also not regulated for safety.
Englisch > Chinesisch: Breakfast and dietary quality General field: Sonstige Detailed field: Medizin: Gesundheitswesen
Ausgangstext - Englisch To determine who had skipped breakfast, they looked at the 24-hour dietary recalls that the survey participants had completed.
They then calculated the nutrient content of what the breakfast skippers reported they’d consumed.
They found that people who skipped breakfast tended to have a very different nutritional profile than those who did eat a morning meal.
When it came to several key nutrients that the team looked at — like fiber, magnesium, copper, and zinc — breakfast skippers also took in less than breakfast eaters.
In addition, the biggest differences in consumption were found in folate, calcium, iron, and vitamins A, B1, B2, B3, C, and D.
Also, breakfast skippers tended to have an overall poorer quality diet due to more snacking, especially on sugars, carbohydrates, and fat.
These foods naturally contain nutrients like calcium, iron, phosphorus, and fiber.
In addition, many of these foods are fortified with important nutrients, he said. Refined grains and cereals have added iron, thiamin, riboflavin, niacin, and folate. Dairy has added vitamins A and D.
Fortification of certain foods is important, Taylor explained, because it adds back nutrients that are lost in the refining process.
Because these foods tend to be unique to a breakfast meal, Taylor said that the nutrients they contain are less likely to be eaten in other meals.
Englisch > Chinesisch: Sleep, dementia and early death General field: Medizin Detailed field: Medizin: Gesundheitswesen
Ausgangstext - Englisch Another strength of the study was the ability to tease apart the impact of having a good bit of trouble falling asleep versus frequent nighttime awakenings on any risk of dementia and death.
"We found a strong association between frequent difficulty falling asleep and nighttime awakenings and dementia and early death from any cause, even after we controlled for things like depression, sex, income, education and chronic conditions," Robbins said.
People who had trouble falling asleep most nights had about a 44% increased risk of an early death from any cause, the study found. Those who said they often woke in the night and struggled to return to sleep had a somewhat higher risk -- a 56% increased risk of early death from any cause.
The risk for dementia was similar: People who reported routinely experiencing difficulty falling asleep had a 49% increased risk of dementia, while those who often woke in the night and had difficulty falling back asleep had a 39% increased risk of dementia.
But it was the people who had a lot of problems falling and staying asleep that had the highest risk of either dementia or dying early from any cause.
A 2017 study found healthy middle-aged adults who slept badly for just one night produced an abundance of beta amyloid plaques -- one of the hallmarks of Alzheimer's disease. Beta amyloid is a sticky protein compound that disrupts communication between brain cells, eventually killing the cells as it accumulates in the brain.
Englisch > Chinesisch: Laughing Gas and antidepressant General field: Medizin Detailed field: Medizin: Pharmazie
Ausgangstext - Englisch The finding follows work with 28 patients struggling with "treatment-resistant major depression," a severe condition that investigators say affects about one-third of all patients — an estimated 17 million American adults — who develop major depressive disorder.
For such patients, antidepressants often fail to provide relief. But following three one-hour laughing gas inhalation sessions spread across three months, 85% of patients had significant depression relief that endured weeks post-treatment.
"Laughing gas is nitrous oxide, one of the oldest and most commonly used anesthetics," explained study author Peter Nagele, chair of anesthesia and critical care at the University of Chicago.
"And we found that laughing gas, at a much lower concentration than is used, for instance, during dental procedures, can help patients with difficult-to-treat depression," Nagele said.
Between 2016 and 2019, Nagele's team tried out two laughing gas formulations: one at a level of 50% nitrous oxide and one at a level of 25%.
Previous investigations had already demonstrated an antidepressant benefit at the higher level. But those efforts only assessed a post-treatment benefit of 24 hours. And patients exposed to the higher dose commonly experienced side effects, including nausea, sedation and or "mild dissociation," a kind of daydreaming experience.
In the latest study, patients were between the ages of 18 and 75. All were told to continue their usual depression care and maintain their existing antidepressant regimen.
About one-third were exposed to three sessions of 50% nitrous oxide inhalation treatment, one-third were given a 25% nitrous oxide inhalation treatment and one-third were given an oxygen inhalation treatment that contained no laughing gas.
Englisch > Chinesisch: NNRTI and liver stiffness General field: Medizin Detailed field: Medizin: Pharmazie
Ausgangstext - Englisch People with HIV who were cured of hepatitis C experienced greater reductions in liver stiffness if they were taking an antiretroviral regimen that contained a non-nucleoside reverse transcriptase inhibitor (NNRTI), Spanish researchers report in the Journal of Antimicrobial Chemotherapy.
Curing hepatitis C infection with direct-acting antiviral treatment can result in improvements in liver health if liver damage is not too advanced. Fibrosis, or scarring of liver tissue caused by an inflammatory reaction to long-term hepatitis C infection, may be reduced after hepatitis C is cured. Liver stiffness is a marker of fibrosis and can be measured by passing sound waves through the liver using a non-invasive device (Fibroscan, or transient elastography). A measurement above 14 kilopascals indicates severe liver damage, or cirrhosis.
Measuring liver stiffness after hepatitis C has been cured can identify people who remain at higher risk of liver complications.
However, it is unclear if the choice of antiretroviral regimen has any effect on liver regeneration. Some antiretroviral drugs less frequently used nowadays have been associated with liver toxicity but the effects of modern antiretroviral therapy on liver regeneration are unknown.
Englisch > Chinesisch: Malarial drug General field: Medizin Detailed field: Medizin: Gesundheitswesen
Ausgangstext - Englisch The compound works by blocking an enzyme called SUB1, which is critical for malaria to burst out of red blood cells. Existing antimalarials work by killing the parasite within the cell, so the researchers hope this alternative drug action will overcome the resistance the parasite has acquired.
Importantly the compound is also able to pass through the membranes of the red blood cell and of the compartment within the cell where the parasites reside.
The team is continuing to optimise the compound, making it smaller and more potent. If successful, it will need to be tested in further experiments and in animal and human trials to show it is safe and effective, before being made available to people.
"This approach, which has already been highly successful at finding new treatments for diseases including HIV and Hepatitis C, could be key to sustained and effective malaria control for many years to come."
Ausgangstext - Englisch "Opioids have been a routine part of postsurgical pain care for decades, but the risk that they could lead to persistent use has been clearly documented," said lead author Dr. Ryan Howard, a surgical resident at Michigan Medicine, the University of Michigan's academic medical center in Ann Arbor.
"Perhaps it's time to make them the exception, not the rule," he noted in a university news release.
Howard and his colleagues analyzed data from more than 22,000 patients who had one of these common types of surgery -- gynecological, hernia, gallbladder, appendix, bowel or thyroid.
Opioids were prescribed to 86% of the patients; 14% received prescriptions for non-opioid painkillers.
Within 30 days, 12% of patients in both groups had complications, emergency department visits or repeat surgery, the study found.
Patients who received non-opioids were slightly more likely to be readmitted to the hospital, but rarely due to pain-related issues, researchers found.
There was no difference between the two groups in the percentage of patients who sought emergency care for pain.
Nearly 6 out of 10 patients completed a survey about their pain in the week after leaving the hospital and other post-surgery issues.
Eighty-two percent of patients in both the opioid and non-opioid groups said they were satisfied with their care and 93% had no regrets about having surgery.
Patients in the non-opioid group were more likely to report being pain-free in the first week after surgery, however, than those in the opioid group (12% versus 7%).
Englisch > Chinesisch: German electricity rationing 德国电力分配 General field: Technik Detailed field: Technik (allgemein)
Ausgangstext - Englisch Germany is now looking to ration its electricity supply to stabilize its green power grid. The European country mulled over the measure amid looming blackouts due to its unstable energy supply.
The country’s energy issues have also threatened the stability of the larger European Union grid.
Germany once had one of the most stable and reliable power grids worldwide when the business of power generation was in the hands of engineers and experts. However, the rise of climate alarmism in the 1990s empowered activists and their political allies to push for “green energy.” Fluctuating and intermittent energy supply could be easily managed at a low cost, they insisted.
Their efforts led to the passing of the Renewable Energy Sources Act (EEG) in 2000. As it turned out, the EEG’s effectivity caused more harm than good to Germany’s power supply. It currently has the highest electricity prices in the world, forcing it to rely more on imports. It has also consistently failed to meet its emissions targets.
Ironically, the German parliament has addressed these issues by relying even more on green energy. It has ordered the closure of the more stable and productive coal and nuclear power plants. Politicians in the country have also passed legislation to limit the amount of power consumed by companies and individuals.
Germany’s economic affairs minister proposes a law limiting power for electric vehicle charging stations
The magazine Tichys Einblick reported that Germany’s Federal Minister for Economic Affairs and Energy Peter Altmaier proposed a law permitting “peak smoothing” for energy providers. Altmaier’s peak smoothing law allows utilities to “temporarily cut off charging power for e-cars” when there is insufficient electricity available. Power utilities have demanded laws similar to what the energy minister proposed, given the instability of wind and solar energy sources.
Altmaier’s draft legislation indicated that “controllable consumption facilities” could have their power supply cut off for up to two hours per day. These facilities, which include charging stations and heat pumps, could be disconnected from the power fully if there was a threat of overloading the grid. The proposal has since been recalled as of writing.
However, the country announced it will make a major push into electric mobility – with a vast expansion slated in the future. Germany only has 33,000 electric charging stations serving 50 million vehicles. The forecasted increase in the number of electric cars will only serve to bolster peak demand for electricity.
Talking about Germany’s power grid issue, Tichys Einblick remarked: “The situation in the power grids has become too critical. The only thing that helps are abstruse ideas like: ‘You are not allowed to [recharge] your car from 10 a.m. to 8 p.m. every day!'”
Relying on 100 percent green energy is good in theory, but bad in practice
According to Tichys Einblick, a number of industries have been on the receiving end of “peak smoothing” efforts for some time now. Cold storage facilities and aluminum smelters have to put up with being disconnected from their power supplies for limited periods. However, the publication noted: “It’s a dangerous game [for aluminum smelters] because after three hours, the molten metal has solidified and the factory is ruined.”
Tichys Einblick continued: “The German government has recognized that in the future electricity system, it will no longer be possible to satisfy every demand at all times. Therefore, the control of the consumer side should be put on legal feet.”
The magazine insinuated that blackouts would be an everyday occurrence. “Controllable consumers such as heat pumps, electric heaters and wall boxes, i.e. charging stations for e-mobiles, would be switched off variably at times,” it said.
One does not need to look across the Atlantic Ocean to see the problem with relying on renewable energy. In July 2018, the state of California asked residents to limit their use of electricity during peak hours. Its call came amid a “heat dome” settling over the southwestern part of the country, leading to more Californians using their air conditioners. Two months prior, the North American Reliable Energy Corporation (NERC) warned that the state faces a “significant risk of encountering operating conditions that could result in operating reserve shortfalls.”
California’s reliance on wind and solar energy gave it an edge over the fight against “global warming” – at the cost of its power supply not meeting the demand.
Ausgangstext - Englisch New rGO-based material could improve energy storage devices and supercapacitors
Researchers from Tomsk Polytechnic University (TPU), along with collaborators from the University of Lille in France, have synthesized a new material, based on reduced graphene oxide (rGO), for energy storage devices and supercapacitors.
The rGO modification technique that involves the use of organic molecules, derivatives of hypervalent iodine, reportedly enabled acquiring a material that is capable of storing 1.7 times more electrical energy.
Despite their potential, supercapacitors are not as widespread as they could be. For further development of the technology, it is required to enhance the efficiency of supercapacitors. One of the key challenges is to increase the energy capacity.
Pavel Postnikov, Associate Professor and Research Supervisor, Research School of Chemistry and Applied Biomedical Science, Tomsk Polytechnic University, said: “It can be achieved by expanding the surface area of an energy storage material, rGO in this particular case. We found a simple and quite fast method. We used exceptionally organic molecules under mild conditions and did not use expensive and toxic metals”.
Powder-form rGO is coated on the electrodes, which leaves hundreds of nanoscale layers of the substance on it. The layers have a propensity to agglomerate, namely, to sinter. The interlayer spacing must be higher to extend the materials’ surface area.
For this purpose, the researchers modified rGO with organic molecules, which resulted in the interlayer spacing increase. Insignificant differences in interlayer spacing allowed increasing energy capacity of the material by 1.7 times. That is, 1 g of the new material can store 1.7 times more energy in comparison with a pristine reduced graphene oxide.
The reaction went ahead with the development of active arynes from iodonium salts. These have an intriguing property to form a single layer of new organic groups on surfaces of the material. Scientists from TPU have been developing the chemistry of iodonium salts for several years.
"The modification reaction proceeds under mild conditions by simply mixing the solution of iodonium salt with reduced graphene oxide. If we compare it with other methods of reduced graphene oxide functionalization, we have achieved the highest indicators of material energy capacity increase", said Elizaveta Sviridova, Study Author and Junior Research Fellow, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University
Ausgangstext - Englisch A winter storm in Texas brought record low temperatures, snow and rolling blackouts across the state. Millions of Texans are still without power, and some people have questioned why a state that produces the most power in the US is unable to keep the lights on. Misinformation about the blackout has also started to spread online, falsely putting the blame on wind and solar energy.
Roughly 3 million people in Texas have had to deal with outages since Monday as power generators and natural gas pipes froze, crippling the state's production capabilities. This led the Electric Reliability Council of Texas (ERCOT), which manages the state's power grid, to administer rolling blackouts to avoid a grid failure.
Here's what you need to know about the power outages in Texas.
What happened?
This past weekend, a winter storm made its way into Texas, bringing freezing cold to the state. As temperatures began to dip into the teens Monday morning, power plant generators across the state started to freeze and went offline, leading to a significant decrease in energy production. At the same time, demand for power increased as people turned up the thermostat.
Almost 50% of power generated by Texas comes from natural gas, with the other half divided among coal, wind, nuclear and solar. Because of the cold, however, gas can't even make its way from the ground through the pipes. ERCOT says 46,000 megawatts were offline as of Wednesday. One megawatt is enough to power roughly 200 homes a year. There are 70 to 80 power plants offline as of Wednesday, out of 680 across the state. Thermal energy -- natural gas, coal and nuclear -- made up 28,000 of those megawatts while wind and solar made up the other 16,000.
"The ability for gas generators to produce, particularly at full output, was affected by the freezing impact on the natural gas supply," Bill Magness, ERCOT president and CEO, said during a livestream Wednesday. "So getting those resources back is the central solution to getting people their power back."
The significant drop in power generated led to rolling blackouts across the state as ERCOT tried to keep a balance between the supply and demand in order to prevent a "catastrophic" blackout. This made the outage last much longer than ERCOT anticipated.
Texas has its own independent power grid and isn't connected to the Eastern Interconnection and the Western Interconnection grids covering the rest of the country. The state is unable to have power diverted to maintain its supply.
Some people are blaming wind and solar. What's the deal?
Confusion over the cause of the blackouts began spreading on social media Tuesday, especially from state government officials.
"The reason for blackouts is complex, but in summary: Texas took too many lessons from Cali, over-subsidized renewables, & pushed out baseload energy like natural gas," Rep. Dan Crenshaw, a Republican from Texas, tweeted Tuesday.
A similar sentiment came from fellow GOP Texas Rep. Ronny Jackson who said on Facebook on Tuesday, "Our reliance on renewable energy needs to be revisited IMMEDIATELY."
But on Tuesday, Texas Gov. Greg Abbott, also a Republican, pointed to freezing natural gas as part of the problem.
"The reason why power is not available for your viewers is because the power generators froze up and their equipment was incapable of generating power. Then on top of that, the natural gas that flows into those power generators, that is frozen up also," Abbott told Houston's ABC-13.
On Tuesday night, though, Abbott went on Sean Hannity's program on Fox News and gave a different explanation of what happened.
"Our wind and solar got shut down, and they are collectively 10% of our power grid, and that thrust Texas into a situation where it was lacking power in a statewide basis," he told Hannity. "As a result, it shows fossil fuel is necessary for the state of Texas."
According to ERCOT officials, however, the majority of power lost came from thermal energy, which is primarily made up of natural gas, and not wind or solar energy.
"As of 9 a.m.," ERCOT said in a press release Wednesday, "approximately 46,000 MW of generation has been forced off the system during this extreme winter weather event. Of that, 28,000 MW is thermal and 18,000 MW is wind and solar."
When will power come back on?
ERCOT doesn't have a specific time when it will be operating at full power, but it's working on restoring power. However, there's more to it than just flicking a switch on.
"Now the challenge has been, we get service restored, and then if the grid gets unstable again because of the issues with the weather and keeping the supply and demand imbalance, we've had to pull those back, unfortunately," Magness said Wednesday.
As more electricity returns to homes, there could be continued rolling blackouts for days until expected warmer weather arrives this weekend.
Englisch > Chinesisch: Energy harvesting 能源收集电路 General field: Technik Detailed field: E-Technik/Elektronik
Ausgangstext - Englisch A team of physicists from the University of Arkansas (U of A) has successfully developed graphene-based circuits capable of providing nearly limitless power for small devices.
Described in a paper published in the journal Physical Review E, the findings prove a theory the physicists developed at the U of A three yeas ago. This theory stated that freestanding graphene – a single layer of carbon atoms – ripples and buckles in a way that holds promise for energy harvesting.
“An energy-harvesting circuit based on graphene could be incorporated into a chip to provide clean, limitless, low-voltage power for small devices or sensors,” said lead researcher Paul Thibado.
Controversial study challenges existing ideas
The research conducted by the U of A scientists has been rather controversial. The idea that freestanding graphene has potential energy-harvesting capabilities refutes a well-known assertation by physicist Richard Feynman that the thermal motion of atoms, known as Brownian motion, cannot do work.
However, the U of A researchers found that at room temperature, the thermal motion of graphene does induce an alternating current in a circuit – something previously thought impossible. In addition, the researchers found that their design increased the amount of power delivered. They stated that they found that the diodes’ switch-like behavior actually amplified the power being delivered instead of reducing it.
“We also found that the on-off, switch-like behavior of the diodes actually amplifies the power delivered, rather than reducing it, as previously thought,” said Thibado. “The rate of change in resistance provided by the diodes adds an extra factor to the power.”
To prove that the diodes increased the circuit’s power, the scientists on the project used a relatively new field of physics called stochastic thermodynamics. This field uses a family of stochastic or random variables to better understand the non-equilibrium dynamics present in many microscopic systems.
In the case of the graphene, the researchers say that it shares a symbiotic relationship with the circuit. While the thermal environment performs work on the load resistor, the circuit and the graphene at the same temperature and heat are not flowing between the two. This is an important discovery as a temperature difference between the two would violate the second law of thermodynamics.
Low-power graphene chips could power electronics in lieu of batteries
As part of their research, the scientists also found that the relatively slow motion of the graphene induces a current in the circuit at low frequencies. This is important from a technological perspective because electronics function much more efficiently at low frequencies.
“People may think that current flowing in a resistor causes it to heat up, but the Brownian current does not. In fact, if no current was flowing, the resistor would cool down,” Thibado explained. “What we did was reroute the current in the circuit and transform it into something useful.”
Before the technology can be used in practical applications in electronics, some more research needs to be done. For the next step, the team is looking to determine with the direct current from the circuit can be stored in a capacitor for later use. This, however, requires that the circuit be miniaturized so that it can be patterned on a silicon wafer or chip.
According to the researchers, should they succeed in doing this, millions of these tiny circuits could be built on a 1-millimeter by 1-millimeter chip which could then serve as a low-power battery replacement.
Englisch > Chinesisch: Integrated GaN gate drive 集成氮化镓栅极驱动 General field: Technik Detailed field: E-Technik/Elektronik
Ausgangstext - Englisch GaN power transistors are becoming the gold standard for fast compact mains power switching – GaN HEMTs have no reverse recovery charge and can be designed with low on-resistance and low parasitic capacitance.
However, their gates are fussy, and unbelievably fussy if all available speed is to be squeezed from this technology. Inappropriate gate drive can permanently weaken the switch transistor by irreversibly injecting charge into layers surrounding the 2D electron gas that HEMTs rely on.
This has lead to the integration of precision gate drivers alongside the transistors, either as a separate CMOS chip inside the transistor package, or by building the driver on the same GaN layer as the transistor – Panasonic did it in 2014 in a dc-dc converter using gate-injection transistors, and Leibniz University Hannover and TI revealed a dc-dc converter at ISSCC2020.
Now National Chiao Tung University has teamed up with Realtek to take integrated drive to its next level, building a temperature compensated three-slope drive into an all-GaN design.
Three slope driving controls the gate differently before, during and after the turn-on Miller plateau – the plateau is an unwanted pause in switch-on when the falling drain voltage capacitively couples into the gate, halting its rise.
In this case, the driver is automatic (see diagram) using three current sources to boost turn-on gate drive, each activated through a fast comparator by its own voltage feedback from the gate signal.
The temperature-dependent characteristics of the main GaN switch – a 650V enhancement-mode (‘e-GaN’) device – are modelled by a PTAT (proportional-to-absolute-temperature) voltage generator which provides suitable thresholds for the three comparators to switch at. The result is strong gate drive without over-drive across -40 to +160°C.
Inside the PTAT generator, cascoded gate-drain-shorted 12V e-GaNs create the temperature-dependent voltages.
All GaN HEMTs are n-channel – there in no equivalent to a p-channel mosfet or pnp transistor. Instead of p-channel fets as high-side devices, in this circuit depletion-mode 12V HEMTs are used as constant-current sources against which the low-side transistors can work – Class-A operation if you like.
Englisch > Chinesisch: Drug replacement study General field: Medizin Detailed field: Medizin (allgemein)
Ausgangstext - Englisch Some of the emerging Covid-19 variants are apparently giving scientists and medical professional sleepless nights. While vaccination against Covid-19 is on around the globe in the hope to end the pandemic, some experts have cautioned that the approved vaccines may not be effective against some dominant variants of the virus. For example, a recent study has shown that the Oxford/AstraZeneca vaccine is less effective against the South Africa variant of COVID-19. And therefore, researchers are also focussing on finding a drug that has the potential of preventing clinical deterioration among COVID-19-infected patients. Luckily, an experimental hepatitis drug has shown promising results in COVID-19 treatment.
COVID-19 patients who were treated with the experimental hepatitis drug called peginterferon-lambda were able to recover from the virus quicker than the placebo group, revealed a study published on 5 February in the Lancet Respiratory Medicine. This drug is typically used in-vitro against hepatitis B and hepatitis C virus.
The study was conducted by a team of researchers from the Toronto Centre for Liver Disease led by Dr Jordan Feld, a liver specialist. They gave 60 COVID-19 patients, who were within seven days of symptoms, either one jab of peginterferon-lambda or a placebo.
One week after the injection, the researchers found that 80 per cent of patients who received the hepatitis drug had undetectable viral loads compared to 63 per cent in the placebo group.
COVID-19 patients who received the injection were also four times more likely to have an undetectable viral load by the seventh day, according to the study.
The hepatitis drug accelerated viral decline in outpatients with mild or moderate COVID-19, particularly in those with high baseline viral load, it noted.
According to the authors, the hepatitis drug peginterferon-lambda may help prevent clinical deterioration and reduce the duration of viral shedding.
Drugs That Made Headlines As Potential COVID-19 Treatments
Currently, there’s no cure for COVID-19, the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, some existing drugs have shown efficacy in treating hospitalised patients with COVID-19 in randomised trials. These include antiviral drug ‘remdesivir’, anti-inflammatory medication ‘dexamethasone’, and rheumatoid arthritis drug baricitinib.
In the US, remdesivir was approved for treatment of COVID-19 pateints who are age 12 and older in the hospital. The FDA had also granted an emergency use authorization for baricitinib to treat COVID-19 in some cases. The agency recommended using baricitinib in combination with remdesivir in COVID-19 patients who are on mechanical ventilators or need supplemental oxygen.
Two monoclonal antibody medications – bamlanivimab and another a combination of two antibodies called casirivimab and imdevimab – were also approved for treatment of mild to moderate COVID-19, particularly in people who are susceptible to serious illness due to the disease under emergency use authorization. Monoclonal antibodies are lab created proteins that help the immune system fight off viruses.
According to the Mayo Clinic, corticosteroid dexamethasone was also recommended for severe COVID-19 patients who require supplemental oxygen or mechanical ventilation.
Convalescent plasma therapy was highly touted as potential treatment for in the early days of the COVID-19 pandemic. But some studies, including one conducted by the Indian Council of Medical Research (ICMR), have shown that it doesn’t help reduce Covid-19 mortality or progression.
Antimalarial drugs Hydroxychloroquine (HCQ) and chloroquine are two other drugs that were in the headlines as potential COVID-19 treatments. However, health authorities revoked use of the drugs after studies found serious cardiac adverse events and other serious side effects in COVID-19 patients given the drugs.
Englisch > Chinesisch: New kind of medicine 新型药物 General field: Medizin Detailed field: Medizin: Pharmazie
Ausgangstext - Englisch In the near future, your doctor might prescribe electricity for what ails you, says Benjamin W Metcalfe
When your only tool is a hammer, every problem looks like a nail. This saying is particularly apt in medicine where doctors treat nearly every condition – from depression to hypertension – with a pill. If your doctor prescribed you anything other than a pill (assuming you don’t need surgery), you might think they were a quack. But this will soon change. Medicine is getting radical, and one of the radical new approaches for treating disease is electricity.
Why electricity? Well, everything you do, from walking to dreaming, is controlled or regulated by electrical signals. These tiny impulses travel through your nervous system, conveying information and allowing complex decisions to be made. The hub of electrical activity is in the brain, and from there the nerves branch out to all corners of the body.
The importance of these electrical signals is demonstrated by the impact of injury to any part of the nervous system, which often leads to irreversible paralysis. The most common trauma involves an injury to the spinal cord. Worldwide, spinal cord injury affects about 2.5 million people with about 130,000 new cases each year.
If we could find a way to read and write the electrical signals, in other words understand the language of the nervous system, we would have a digital interface to the body. An implanted device would then be able to bridge the gap left by a spinal cord injury.
And it’s not just people with spinal cord injuries who would benefit from this kind of technology. We could instruct the pancreas to produce more insulin, or we could raise or lower the heart rate without needing to resort to pills. In essence, we could take control of the body.
Dancing frogs
Luigi Galvani was one of the first scientists to realise that electricity might have some involvement in the normal operation of life. He discovered this in 1791 when he conducted experiments on frogs, making their legs twitch with electricity. A century later, the idea of an artificial cardiac pacemaker was first mooted.
Today bioelectronics is a highly active field of research, yet in the two centuries since Galvani first made his frogs dance there are still only a handful of commercially available devices that interface with the nervous system. The most common is the pacemaker, a device that was first implanted in 1958. The patient outlived both the surgeon and the engineer who invented it.
A promising target for new devices is the vagus nerve. This nerve, which runs down both sides of your neck, is connected to many organs, and devices that stimulate it may be able to treat diseases as far ranging as rheumatoid arthritis and alcoholism.
One of the key success stories has been a device for treating drug-resistant epilepsy. This device, made by LivaNova, has been used by over 100,000 people. It helps prevent the abnormal electrical activity that causes seizures within the brain by applying small electrical impulses at regular intervals 24 hours a day, every day. These impulses travel up the vagus nerve and into the brain.
More than 40 per cent of patients fitted with this device reduce their number of seizures by half. However, the constant stimulation can cause unwanted side effects, including pain, headaches and shortness of breath.
Advances are being made
While stimulating the vagus nerve with electricity is clearly beneficial, it’s still quite a crude approach. Stimulating the nerve is like shouting an instruction rather than joining a conversation. It would be much more powerful if we could record the messages already travelling along the nerves. These messages might alert us to the onset of an epileptic seizure, for example, and enable on-demand stimulation that mitigates the unwanted side effects of the current system.
However, recording signals in a nerve isn’t easy. The vagus nerve contains tens of thousands of neurons and each electrical signal is incredibly weak and hard to detect. Coupled with this is the fact that interfering signals from muscles are often 100 times larger than the signals within the nerves.
In order to detect an impending seizure, for example, an implanted device must be able to record and identify one small signal from another, at the same time. This is not unlike being at a rock concert and trying to listen to a conversation on the other side of the stadium.
Despite these challenges, the continuing work of scientists, physicians and engineers is starting to make the dream of bioelectronic medicine a reality. Advances in electrode technology, signal processing and implant design have all played a key role. New recordings made from the vagus nerve have decoded information about breathing that might be vital in the design of devices that treat respiratory disorders.
More than two centuries after Luigi Galvani made his frogs dance, the true possibilities of neural interfaces are finally coming to fruition. And the vagus nerves are not the only targets. Research in England is aiming to restore bladder control to patients with spinal cord injury by recording signals from the sacral nerves, and worldwide there is a renewed effort to create prosthetic limbs that are controlled directly by the patient’s thoughts.
Electricity may not replace conventional drugs, but in the not too distant future, it will surely complement them.
Ausgangstext - Englisch New graphene hybrid material could open the door to highly efficient supercapacitors
A research team working with Roland Fischer, Professor of Inorganic and Metal-Organic Chemistry at the Technical University Munich (TUM), has developed a highly efficient supercapacitor based on a novel, powerful and sustainable graphene hybrid material that reportedly has comparable performance data to currently utilized batteries.
A common problem with supercapacitors to date was their lack of energy density. While lithium accumulators reach an energy density of up to 265 Kilowatt hours (KW/h), supercapacitors thus far have only been able to deliver a fraction of that. The team working with TUM's Roland Fischer has now developed a novel, powerful as well as sustainable graphene hybrid material for supercapacitors. It serves as the positive electrode in the energy storage device. The researchers are combining it with a proven negative electrode based on titan and carbon.
The team reports that the new energy storage device does not only attain an energy density of up to 73 Wh/kg, which is roughly equivalent to the energy density of a nickel metal hybrid battery, but also performs much better than most other supercapacitors at a power density of 16 kW/kg. The secret of the new supercapacitor is the combination of different materials – hence, chemists refer to the supercapacitor as “asymmetrical.”
The researchers are betting on a new strategy to overcome the performance limits of standard materials – they utilize hybrid materials. “Nature is full of highly complex, evolutionarily optimized hybrid materials – bones and teeth are examples. Their mechanical properties, such as hardness and elasticity were optimized through the combination of various materials by nature,” says Roland Fischer.
As a basis, the researchers used the novel positive electrode of the storage unit with chemically modified graphene and combined it with a nano-structured metal organic framework, a so-called MOF.
Graphene hybrids display a large specific surface and controllable pore sizes, and also a high electrical conductivity. “The high performance capabilities of the material is based on the combination of the microporous MOFs with the conductive graphene acid,” explains first author Jayaramulu Kolleboyina, a former guest scientist working with Roland Fischer.
A large surface area is important for supercapacitors. It allows for the collection of a respectively large number of charge carriers within the material – this is the basic principle for the storage of electrical energy.
Through skillful material design, the researchers achieved the feat of linking the graphene acid with the MOFs. The resulting hybrid MOFs have a very large inner surface of up to 900 square meters per gram and are highly performant as positive electrodes in a supercapacitor.
However, that is not the only advantage of the new material. To achieve a chemically stable hybrid, one needs strong chemical bonds between the components. The bonds are apparently the same as those between amino acids in proteins, according to Fischer: “In fact, we have connected the graphene acid with a MOF-amino acid, which creates a type of peptide bond.”
The stable connection between the nano-structured components has huge advantages in terms of long term stability: The more stable the bonds, the more charging and discharging cycles are possible without significant performance impairment.
For comparison: A classic lithium accumulator has a useful life of around 5,000 cycles. The new cell developed by the TUM researchers retains close to 90 percent capacity even after 10,000 cycles.
Fischer emphasizes how important the international cooperation was to the development of the new supercapacitor. Jayaramulu Kolleboyina built the team. He was a guest scientist from India invited by the Alexander von Humboldt Foundation who by now is the head of the chemistry department at the newly established Indian Institute of Technology in Jammu.
“Our team also networked with electro-chemistry and battery research experts in Barcelona as well as graphene derivate experts from the Czech Republic,” reports Fischer. “Furthermore, we have integrated partners from the USA and Australia. This wonderful, international co-operation promises much for the future.”
Englisch > Chinesisch: Graphene development General field: Technik Detailed field: E-Technik/Elektronik
Ausgangstext - Englisch Graphene is a thin layer of pure carbon, tightly packed and bonded together in a hexagonal honeycomb lattice. It is widely regarded as a “wonder material” because it is endowed with an abundance of astonishing traits: it is the thinnest compound known to man at one atom thick, as well as the best known conductor. It also has amazing strength and light absorption traits and is even considered ecologically friendly and sustainable as carbon is widespread in nature and part of the human body.
Graphene is often suggested as a replacement for activated carbon in supercapacitors, in part due to its high relative surface area (which is even more substantial than that of activated carbon). The surface area is one of the limitations of capacitance and a higher surface area means a better electrostatic charge storage. In addition, graphene based supercapacitors will utilize its lightweight nature, elastic properties and mechanical strength.
A Graphene supercapacitor is said to store almost as much energy as alithium-ion battery, charge and discharge in seconds and maintain all this over tens of thousands of charging cycles. One of the ways to achieve this is by using a a highly porous form of graphene with a large internal surface area (made by packing graphene powder into a coin-shaped cell and then dry and press it).
What are supercapacitors?
Supercapacitors, also known as EDLC (electric double-layer capacitor) or Ultracapacitors, differ from regular capacitors in that they can store tremendous amounts of energy.
A basic capacitor usually consists of two metal plates, separated by an insulator (like air or a plastic film). During charging, electrons accumulate on one conductor and depart from the other. One side gains a negative charge while the other side builds a positive one. The insulator disturbs the natural pull of the negative charge towards the positive one, and that tension creates an electric field. Once electrons are given a path to the other side, discharge occurs.
Supercapacitors also contain two metal plates, only coated with a porous material known as activated carbon. They are immersed in an electrolyte made of positive and negative ions dissolved in a solvent. One plate is positive and the other is negative. During charging, ions from the electrolyte accumulate on the surface of each carbon-coated plate. Supercapacitors also store energy in an electric field that is formed between two oppositely charged particles, only they have the electrolyte in which an equal number of positive and negative ions is uniformly dispersed. Thus, during charging, each electrode ends up having two layers of charge coating (electric double-layer).
Batteries and Supercapacitors
Unlike capacitors and supercapacitors, batteries store energy in a chemical reaction. This way, ions are inserted into the atomic structure of an electrode, instead of just clinging to it like in supercapacitors. This makes supercapacitors (and storing energy without chemical reactions in general) able to charge and discharge much faster than batteries. Due to the fact that a supercapacitor does not suffer the same wear and tear as a chemical reaction based battery, it can survive hundreds of thousands more charge and discharge cycles.
Supercapacitors boast a high energy storage capacity compared to regular capacitors, but they still lag behind batteries in that area. Supercapacitors are also usually more expensive per unit than batteries. Technically, it is possible to replace the battery of a cell phone with a supercapacitor, and it will charge much faster. Alas, it will not stay charged for long. Supercapacitors are very effective, however, at accepting or delivering a sudden surge of energy, which makes them a fitting partner for batteries. Primary energy sources such as internal combustion engines, fuel cells and batteries work well as a continuous source of low power, but cannot efficiently handle peak power demands or recapture energy because they discharge and recharge slowly. Supercapacitors deliver quick bursts of energy during peak power demands and then quickly store energy and capture excess power that's otherwise lost. In the example of an electric car, a supercapacitor can provide needed power for acceleration, while a battery provides range and recharges the supercapacitor between surges.
Common supercapacitor applications
Supercapacitors are currently used to harvest power from regenerative braking systems and release power to help hybrid buses accelerate, provide cranking power and voltage stabilization in start/stop systems, backup and peak power for automotive applications, assist in train acceleration, open aircraft doors in the event of power failures, help increase reliability and stability of the energy grid of blade pitch systems, capture energy and provide burst power to assist in lifting operations, provide energy to data centers between power failures and initiation of backup power systems, such as diesel generators or fuel cells and provide energy storage for firming the output of renewable installations and increasing grid stability.
Rivaling materials
Several materials exist that are researched and suggested to augment supercapacitors as much (or even more than) graphene. Among these materials are: hemp, that was used by Canadian researchers to develop hemp fibers that are at least as efficient as graphene ones in supercapacitor electrodes, Cigarette filters, which were used by Korean researchers to prepare a material for supercapacitor electrodes that exhibits a better rate capability and higher specific capacitance than conventional activated carbon and even higher than N-doped graphene or N-doped CNT electrodes.
Englisch > Chinesisch: HIV trial news update General field: Medizin Detailed field: Medizin (allgemein)
Ausgangstext - Englisch Experimental HIV vaccine trial shows promising results, prompting researchers to partner with Moderna
A study that could one day lead to a potential HIV vaccine has shown promising results, scientists have said.
Researchers from the International AIDS Vaccine Initiative (IAVI) and Scripps Research say that a phase-one trial has shown “proof in principle” for a new type of vaccine that could be used against the virus.
An effective vaccine to prevent HIV infection has proved elusive for nearly four decades, not least because the virus constantly evolves into different strains to evade the immune system.
However, the trial found success in “stimulating production of rare immune cells needed to start the process of generating antibodies” that could neutralise diverse strains of HIV.
Study ‘demonstrates proof of principle’ for HIV vaccine concept
The trial succeeded in generating cell production in 97 per cent of participants, though researchers stressed it is only a first step.
Professor William Schief, executive director of vaccine design at IAVI’s Neutralizing Antibody Center, said in a release: “This study demonstrates proof of principle for a new vaccine concept for HIV, a concept that could be applied to other pathogens, as well.
“With our many collaborators on the study team, we showed that vaccines can be designed to stimulate rare immune cells with specific properties, and this targeted stimulation can be very efficient in humans.
“We believe this approach will be key to making an HIV vaccine and possibly important for making vaccines against other pathogens.”
The researchers are now partnering with biotechnology company Moderna to develop and test an mRNA-based vaccine – the same radical approach employed in the creation of coronavirus vaccines.
Results could pave the way for future breakthroughs
IAVI boss Mark Feinberg, said in a release: “These exciting findings emerge from remarkably creative, innovative science and are a testament to the research team’s talent, dedication and collaborative spirit, and to the generosity of the trial participants.
“Given the urgent need for an HIV vaccine to rein in the global epidemic, we think these results will have broad implications for HIV vaccine researchers as they decide which scientific directions to pursue.
“The collaboration among individuals and institutions that made this important and exceptionally complex clinical trial so successful will be tremendously enabling to accelerate future HIV vaccine research.”
Dennis Burton, director of the NIH Consortium for HIV/AIDS Vaccine Development, said: “This clinical trial has shown that we can drive immune responses in predictable ways to make new and better vaccines, and not just for HIV.
“We believe this type of vaccine engineering can be applied more broadly, bringing about a new day in vaccinology.”
Englisch > Chinesisch: MOSFET驱动电路设计 General field: Technik Detailed field: E-Technik/Elektronik
Ausgangstext - Englisch MOSFETs are widely used in switching power supplies due to their low internal resistance and fast switching speed. The MOSFET often selects a appropriate driver circuit based on the parameters of the power-supply IC and MOSFET. Let's discuss the drive circuits of MOSFETs for switching power supplies.
When using a MOSFET to design a switching power supply, most people will consider the parameters of on-resistance, maximum voltage and maximum current of the MOSFET. But that's it. We always only taking these factors into consideration. Such a circuit designed in this way is far from being a good circuit. We should take a closer look at its own parasitic parameters. For a certain MOSFET, its drive circuit, the peak output drive current, the rising rate and etc. will all affect the switching performance of MOSFET.
When the power-supply IC and MOS transistor are selected, it is especially important to select an appropriate driver circuit to connect the IC to the transistor.
A good MOSFET driver circuit has the following requirements:
1. When the switching transistor is turned on, the drive circuit should be able to provide a large enough charging current to rapidly increase the voltage between the gate and source terminals of the MOSFET to the required value, ensuring that not only the switching transistor can be quickly turned on but also there is no high-frequency oscillation on the rising edge.
2. During the on-time of the switch, the driver circuit can ensure that the voltage between the gate and source terminals of the MOSFET remains stable and reliably turned on.
3. At the moment of turn-off, the driver circuit can provide a path with as low impedance as possible to quickly discharge the capacitor's voltage between the gate and source terminals of the MOSFET, ensuring that the switch can be quickly turned off.
4. The circuit structure should be simple, efficient and reliable.
5. Electrical isolation is applied accordingly.
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