The kilogram has put on weight

January 8, 2013

kilogram

London:Jan 8: The official kilogram - a cylinder-shaped hunk of metal - that defines the fundamental unit of mass, has itself gained weight, scientists say.

Scientists at Newscastle University have found that due to surface contamination the original kilogram is likely to be tens of microgrammes heavier than it was when the first standard was set in 1875.

As a result, each country that has one of these standard masses has a slightly different definition of the kilogram, which could throw off science experiments that require very precise weight measurements or international trade in highly restricted items that are restricted by weight, such as radioactive materials.

The original kilogram - known as the International Prototype Kilogram or the IPK - is the standard against which all other measurements of mass are set.

Stored in the International Bureau of Weights and Measures in Paris, 40 official replicas of the IPK were made in 1884 and distributed around the world in order to standardise mass.

Now Professor Peter Cumpson and Dr Naoko Sano have used cutting-edge X-ray Photoelectron Spectroscopy to analyse surfaces similar to the standard kilogram to assess the build-up of hydrocarbons – and how to remove them.

Ozone and ultraviolet light could be used to clean the kilograms without damaging them, LiveScience reported.

“Statute decrees the IPK is the kilogram,” explained research lead Peter Cumpson, Professor of MicroElectroMechanical Systems at Newcastle University.

“It doesn’t really matter what it weighs as long as we are all working to the same exact standard. The problem is there are slight differences. Around the world, the IPK and its 40 replicas are all growing at different rates, diverging from the original,” Cumpson said.

“We’re only talking about a very small change – less than 100 microgrammes – so, unfortunately, we can’t all take a couple of kilograms off our weight and pretend the Christmas over-indulgence never happened,” Cumpson added.

“But mass is such a fundamental unit that even this very small change is significant and the impact of a slight variation on a global scale is absolutely huge. There are cases of international trade in high-value materials or waste where every last microgramme must be accounted for,” he said.

“What we have done at Newcastle is effectively give these surfaces a suntan. By exposing the surface to a mixture of UV and ozone we can remove the carbonaceous contamination and potentially bring prototype kilograms back to their ideal weight,” he added.

Work is underway internationally in several national measurement institutes to find an alternative to the IPK — a standardised value for the kilogram that is not based on a matchbox—sized piece of metal.

The study was published in the journal of Metrologia.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
February 6,2020

Researchers have found the rates of lung cancer are higher in young women than men.

The study, published in the journal Pediatrics, examined lung cancer rates in young adults in 40 countries across five continents and uncovered a trend of higher lung cancer rates in women compared with men in recent years.

The emerging trend was widespread, affecting countries across varied geographic locations and income levels.

The changes appeared to be driven by a rising rate of adenocarcinoma lung cancer among women, said the study researchers from University of Calgary in Canada.

Lung cancer rates have been higher among men than women because men started smoking in large numbers earlier and smoked at higher rates; however, recent studies have reported converging lung cancer incidence rates between sexes.

Among men, age specific lung cancer incidence rates generally decreased in all countries, while in women the rates varied across countries with the trends in most countries stable or declining, albeit at a slower pace compared to those in men.

For the findings, lung and bronchial cancer cases between 30-64 age group from 1993-2012 were extracted from cancer incidence in five continents.

The study found the higher emerging rates of lung cancer in young women compared to young men.

According to the researchers, future studies are needed to identify reasons for the elevated incidence of lung cancer among young women.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
July 3,2020

Apart from the many benefits of doing exercise, new research has now found that exercise can slow down or prevent the development of macular degeneration and may benefit other common causes of vision loss, such as glaucoma and diabetic retinopathy.

The new study from the University of Virginia School of Medicine found that exercise reduced the harmful overgrowth of blood vessels in the eyes of lab mice by up to 45 per cent. This tangle of blood vessels is a key contributor to macular degeneration and several other eye diseases.

The study represents the first experimental evidence showing that exercise can reduce the severity of macular degeneration, a leading cause of vision loss, the scientists report. Ten million Americans are estimated to have the condition.

"There has long been a question about whether maintaining a healthy lifestyle can delay or prevent the development of macular degeneration. The way that question has historically been answered has been by taking surveys of people, asking them what they are eating and how much exercise they are performing," said researcher Bradley Gelfand, PhD, of UVA's Center for Advanced Vision Science.

"That is basically the most sophisticated study that has been done. The problem with that is that people are notoriously bad self-reporters ... and that can lead to conclusions that may or not be true. This [study] offers hard evidence from the lab for the very first time," Gelfand added.

Enticingly, the research found that the bar for receiving the benefits from exercise was relatively low - more exercise didn't mean more benefit.

"Mice are kind of like people in that they will do a spectrum of exercise. As long as they had a wheel and ran on it, there was a benefit. The benefit that they obtained is saturated at low levels of exercise," Gelfand said.

An initial test comparing mice that voluntarily exercised versus those that did not found that exercise reduced the blood vessel overgrowth by 45%. A second test, to confirm the findings, found a reduction of 32 per cent.

The scientists aren't certain exactly how exercise is preventing the blood vessel overgrowth. There could be a variety of factors at play, they say, including increased blood flow to the eyes.

Gelfand, of UVA's Department of Ophthalmology and Department of Biomedical Engineering, noted that the onset of vision loss is often associated with a decrease in exercise.

"It is fairly well known that as people's eyes and vision deteriorate, their tendency to engage in physical activity also goes down. It can be a challenging thing to study with older people. ... How much of that is one causing the other?" he said.
The researchers already have submitted grant proposals in hopes of obtaining funding to pursue their findings further.

"The next step is to look at how and why this happens, and to see if we can develop a pill or method that will give you the benefits of exercise without having to exercise," Gelfand said.

He explained, "We're talking about a fairly elderly population [of people with macular degeneration], many of whom may not be capable of conducting the type of exercise regimen that may be required to see some kind of benefit." (He urged people to consult their doctors before beginning any aggressive exercise program.)
Gelfand, a self-described couch potato, disclosed a secret motivation for the research: "One reason I wanted to do this study was sort of selfish. I was hoping to find some reason not to exercise," he joked. "It turned out exercise really is good for you."

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
June 10,2020

Early treatment with the antiviral drug remdesivir has been found to reduce viral load and prevent lung disease in macaques infected with SARS-CoV-2 that causes COVID-19, according to a study.

The findings, published in the journal Nature on Tuesday, support the early use of remdesivir treatment in patients with COVID-19 to prevent progression to pneumonia.

Researchers from the National Institutes of Health in the US noted that remdesivir has broad antiviral activity and has been shown to be effective against infections with SARS-CoV and MERS-CoV in animal models.

The drug is being tested in human clinical trials for the treatment of COVID-19, they said.

Researcher Emmie de Wit and colleagues investigated the effects of remdesivir treatment in rhesus macaques, a recently established model of SARS-CoV-2 infection.

Two sets of six macaques were inoculated with SARS-CoV-2.

One group was treated with remdesivir 12 hours later -- close to the peak of virus reproduction in the lungs -- and these macaques received treatment every 24 hours until six days after inoculation.

In contrast to the control group, the researchers found that macaques that received remdesivir did not show signs of respiratory disease, and had reduced damage to the lungs.

Viral loads in the lower respiratory tract were also reduced in the treated animals; viral levels were around 100 times lower in the lower-respiratory tract of remdesivir-treated macaques 12 hours after the first dose, they said.

The researchers said that infectious virus could no longer be detected in the treatment group three days after initial infection, but was still detectable in four out of six control animals.

Despite this virus reduction in the lower respiratory tract, no reduction in virus shedding was observed, which indicates that clinical improvement may not equate to a lack of infectiousness, they said.

Dosing of remdesivir in the rhesus macaques is equivalent to that used in humans, the researchers noted.

They cautioned that it is difficult to directly translate the timing of treatment used in corresponding disease stages in humans, because rhesus macaques normally develop only mild disease.

However, researchers said the results indicate that remdesivir treatment of COVID-19 should be initiated as early as possible to achieve the maximum treatment effect.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.