Category Archives: Science

How Do You Lose Weight While You Sleep?

In this interesting webcast, Derek Muller, (a physics teacher in Perth, Australia) explores how much weight you lose while you sleep. As physics teacher he asks the sensible question: how do you lose weight while you sleep, what weight do you lose?

His conclusion is you lose weight through perspiration, water vapor in your breath and expelling carbon dioxide. Losing the water weight is pretty straight forward. The process of adding carbon to the breath we expel is not something I thought of. He calculates that we lose about 100 grams of carbon during a night of sleep. In his somewhat scientific experiment (measuring himself for several days) he lost about 150 more grams, which he attributes to water vapor and perspiration.

It seems to me the amount of carbon we lose during sleep is probably much more consistent than the amount of water weight we lose (both between people and variation between different days).

Drugmakers Are Desperate to Know Why Placebos Are Getting More Effective

Fascinating article from Wired: Placebos Are Getting More Effective. Drugmakers Are Desperate to Know Why.

The fact that an increasing number of medications are unable to beat sugar pills has thrown the industry into crisis. The stakes could hardly be higher. In today’s economy, the fate of a long-established company can hang on the outcome of a handful of tests.
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Potter discovered, however, that geographic location alone could determine whether a drug bested placebo or crossed the futility boundary. By the late ’90s, for example, the classic antianxiety drug diazepam (also known as Valium) was still beating placebo in France and Belgium. But when the drug was tested in the US, it was likely to fail. Conversely, Prozac performed better in America than it did in western Europe and South Africa. It was an unsettling prospect: FDA approval could hinge on where the company chose to conduct a trial.
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In one study, Benedetti found that Alzheimer’s patients with impaired cognitive function get less pain relief from analgesic drugs than normal volunteers do. Using advanced methods of EEG analysis, he discovered that the connections between the patients’ prefrontal lobes and their opioid systems had been damaged. Healthy volunteers feel the benefit of medication plus a placebo boost. Patients who are unable to formulate ideas about the future because of cortical deficits, however, feel only the effect of the drug itself. The experiment suggests that because Alzheimer’s patients don’t get the benefits of anticipating the treatment, they require higher doses of painkillers to experience normal levels of relief.

Benedetti often uses the phrase “placebo response” instead of placebo effect. By definition, inert pills have no effect, but under the right conditions they can act as a catalyst for what he calls the body’s “endogenous health care system.” Like any other internal network, the placebo response has limits. It can ease the discomfort of chemotherapy, but it won’t stop the growth of tumors. It also works in reverse to produce the placebo’s evil twin, the nocebo effect. For example, men taking a commonly prescribed prostate drug who were informed that the medication may cause sexual dysfunction were twice as likely to become impotent.
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Moreover, a pill’s shape, size, branding, and price all influence its effects on the body. Soothing blue capsules make more effective tranquilizers than angry red ones, except among Italian men, for whom the color blue is associated with their national soccer team—Forza Azzurri!

Medical research presents significant difficulties. The funding of the health care system also distorts behavior and pushes companies to focus on being able to justify selling drugs instead of focusing on finding effective solutions. Even without incentives distorting behavior, the challenges are difficult enough. Adding the distortions just makes it worse.

It is wonderful we have so many scientists accepting these challenges and spending their careers fighting the odds to help find us wonderful health breakthroughs.

Appropriate Technology Health Care Solution Could Save 72,000 Lives a Year

We need more medical solutions that serve the majority of humanity instead of just the rich. Some medical research is innately costly and therefore require large costs to pay back the investment. But too little concern is shown for solutions that help people (with so much focus only on solutions that will make organizations rich).

Cheap vinegar test cut cervical cancer deaths in India; could help many poor countries

This low-tech visual exam cut the cervical cancer death rate by 31 percent, the study found. It could prevent 22,000 deaths in India and 72,600 worldwide each year, researchers estimate.
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More progress against cervical cancer may come from last month’s announcement that two companies will drastically lower prices on HPV vaccines for poor countries. Pilot projects will begin in Asia and Africa; the campaign aims to vaccinate more than 30 million girls in more than 40 countries by 2020.

India continues to invest in medical research for solutions that are affordable to a majority of the world. The rich health care companies largely neglect the majority to focus on the most wealthy.

Webcast: Examining the Scientific Basis Around Exercise and Diet Claims

Tim Noakes is the Director of UCT/MRC Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Science, University of Cape Town and Professor, Discovery Health Chair of Exercise and Sports Science, University of Cape Town.

Tim examines some questions on science and exercise and health in the webcast. He shows the problem with drinking too much during exercise and the correlation of hospital admissions correlated to the sport drinks marketing and changing of the official drinking guidelines. He also discusses the outdated ideas related to lactic acid and muscles.

He is currently studying the science of food and human health and is skeptical of low fat health claims: “No evidence that dietary fat is related to heath disease.” He is certainly more knowledgable than I but I would still be cautious of completely accepting that premise. It does seem to me there is lots of evidence that claims of causation between eating a high fat diet and heart disease were too strong (many other factors were critical – such as weight, exercise, genetics, unsaturated fat v. saturated fat…).

Tim Noaks: “50% of what we teach is wrong; the problem is we don’t know which 50% it is. Our job as educated people is to spend our lifetime trying to figure out which 50% is which. Until it is disproven accept that for which the evidence appears solid and logical and is free of covert or overt conflicts of interest, because unfortunately industry is driving what you believe in many many things. But don’t ever dismis lightly that for which there is credible evidence… and there is such clear evidence the diets we are eating are horrendous.”

As I have said before, scientific literacy is critical to allow us to make those judgements about what is credible evidence and what are outright lies, foolish claims or highly suspicious claims tainted by conflicts of interest.

Europe Bans Certain Pesticides, USA Just Keeps Looking, Bees Keep Dying

For years the bee colony collapse disorder has been showing the difficulty of the scientific inquiry process. And that difficulty often becomes more difficult if interests with lots of money at stake want to block certain conclusions.

One-Third of U.S. Honeybee Colonies Died Last Winter, Threatening Food Supply

Multiple factors — pesticides, fungicides, parasites, viruses and malnutrition — are believed to cause the losses, which were officially announced today by a consortium of academic researchers, beekeepers and Department of Agriculture scientists.

“We’re getting closer and closer to the point where we don’t have enough bees in this country to meet pollination demands,” said entomologist Dennis vanEngelstorp of the University of Maryland, who led the survey documenting the declines.

Beekeepers lost 31 percent of their colonies in late 2012 and early 2013, roughly double what’s considered acceptable attrition through natural causes. The losses are in keeping with rates documented since 2006, when beekeeper concerns prompted the first nationwide survey of honeybee health. Hopes raised by drop in rates of loss to 22 percent in 2011-2012 were wiped out by the new numbers.
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Most losses reported in the latest survey, however, don’t actually fit the CCD profile. And though CCD is largely undocumented in western Europe, honeybee losses there have also been dramatic. In fact, CCD seems to be declining, even as total losses mount. The honeybees are simply dying.

“Even if CCD went away, we’d still have tremendous losses,” said entomologist Diana Cox-Foster at Pennsylvania State University. “CCD losses are like the straw that breaks the camel’s back. The system has many other issues.”

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Pew Science and Technology Knowledge Quiz

The Pew Science and Technology Knowledge Quiz is a simple 13 question quiz to get a very simple look at scientific understanding in society. Obviously these types of quizes are just extremely simple views, still it is interesting to see how you can do and what questions people struggle with.

graphic showing 13 of 13 answers correct

I am surprised the fewer than 50% of the people got 2 true or false questions correct, including “Electrons are smaller than atoms. Is this statement…” Looking back at my previous post, I guess I shouldn’t be surprised, in the 2009 Pew Science Knowledge Quiz it is also the case that under 50% got the are electrons smaller than atoms question right.

They also provided a breakdown by demographic factors. Men had better percentages of correct answers, for the 2 true or false questions men were correct 55% of the time while women got 40% correct. The two other true of false questions had much higher correct answer rates 77% (83% for men 72% for women) and 66% (70 for men, 63 for women).

There was also a substantial tendency for the youngest ages to do better and the performance to decline for each age group. I am not surprised by the question answered incorrectly most often (only 20% got it right), see if you can guess which it is.

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Can You Effectively Burn Calories by Drinking Cold Water?

Neil deGrasse Tyson stated on Twitter:

Wanna lose 1200 Calories a month? Drink a liter of ice water a day. You burn the energy just raising the water to body temp.

What if your body is trying to cool down? I would imagine we have to use energy to cool off (though I am no expert on this)? So if you drink cold water and your body has less need to cool off, couldn’t this actually end up “saving” your body needing to burn calories – and thus cause yourself to gain weight?

This model would be similar to a server room that was cooled with air conditioning and cold winter air to cool off the servers. If there was less cold air used then more electricity would be used running the air conditioner to cool down the servers. I don’t know if it is a decent analogy though – maybe that isn’t an usable model for how we cool off.

I know we cool off partially by pushing water out onto the exterior of our skin to have it evaporate and cool us off. I would think that takes energy to do.

I do get that it takes energy to raise the temperature of the water you consume. It does make sense to me that if you were cold (like say I was during the winter living in the house I grew up in) you would use energy raising the temperature of the water.

What the overall energy situation is if your body needs to cool down seems questionable to me. Please let me know your thoughts. In any event his statement is accurate. It is just that the implication may lead people astray; that you can consume 1,200 Calories extra to balance the 1,200 Calories drinking cold water uses (or loss weight by having reduced your excess Calories by 1,200 if you eat exactly the same things you would without the cold water).

Building A Better Bed Bug Trap Using Bean Leaves

Building A Better Bed Bug Trap

An old folk remedy involving hairy bean leaves strewn around the bedroom may have a new life as a modern bed bug trap, according to new research from the University of California, Irvine and the University of Kentucky.
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Although its mechanisms weren’t known at the time, the tactic dates back to at least 1678, when the English philosopher John Locke wrote of placing kidney bean leaves under the pillow or around the bed to keep bed bugs from biting as he traveled through Europe.

In the early twentieth century, the approach was also common throughout the Balkans, according to a 1927 report from the Imperial and Royal Austro-Hungarian Army. That report suggested the leaves stunned the bloodsucking bugs as they traveled from hiding places to their sleeping hosts during the night; in the morning, the bug-covered leaves were removed and burned.
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“The inconvenience of bean leaves is that not everyone wants them scattered around their bed room.” Synthetics mimicking the surface of the bean leaf, however, could be placed “as a ring around the bed legs, a floor mat at the door, a strip on the bed board, it could be something one put’s in one’s suitcase,”

Very cool. The chemical assault on bed buds is failing all over the world. A new vector to assist in the fight against bed bugs will be most welcome. It is interesting to learn the scientific reasons that explain why some folk remedies work.

Cell Aging and Limits Due to Telomeres

When cells divide the process fails to copy DNA all the way to the end. Telomeres are are the end of DNA strands, as essentially a buffer of material that won’t cause information to be lost when part of the telomere isn’t copied. As DNA is copied, as new cells are created, the length of telomeres at the end is reduced. Once the telomeres are gone the cell will no longer divide.

The 2009 Nobel Prize in Physiology or Medicine went to 3 scientists for discovering how the chromosomes can be copied in a complete way during cell divisions and how they are protected against degradation. The Nobel Laureates have shown that the solution is to be found in the ends of the chromosomes – the telomeres – and in an enzyme that forms them – telomerase.

There is some debate over the benefit of the mechanism of cells not dividing do to lack of telomere. This can prevent cancerous cells from replicating (once they replicate to the extent that the necessary telomere buffer is gone). It is also seen that as telomeres get shorter the cells become more likely to become cancerous.

Cancer also can stimulate the production of telomerase which can stop telomeres from getting shorter as cells divide and thus allow the cancer cells to keep dividing (thus producing more cancer cell and increasing the amount of cancerous cells). Using telomerase to allow health cells to avoid the limits of division is being researched.

Are Telomeres the Key to Aging and Cancer? (University of Utah)

An enzyme named telomerase adds bases to the ends of telomeres. In young cells, telomerase keeps telomeres from wearing down too much. But as cells divide repeatedly, there is not enough telomerase, so the telomeres grow shorter and the cells age.
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Cells normally can divide only about 50 to 70 times, with telomeres getting progressively shorter until the cells become senescent, die or sustain genetic damage that can cause cancer.
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shorter telomeres are associated with shorter lives. Among people older than 60, those with shorter telomeres were three times more likely to die from heart disease and eight times more likely to die from infectious disease.

While telomere shortening has been linked to the aging process, it is not yet known whether shorter telomeres are just a sign of aging – like gray hair – or actually contribute to aging.

Huge Human Population Boom 40,000 to 50,000 Years Ago

Interesting open access paper on looking at the Y-chromosome to explore our ancestry: A calibrated human Y-chromosomal phylogeny based on resequencing. I can’t understand all the details but the basic idea isn’t that complicated. It is interesting to see these details as are the conclusions that can be drawn: that we had a big explosion of human population o 41,000–52,000 years ago.

This population explosion occurred, between the first expansion of modern humans out of Africa 60,000 to 70,000 years ago and the Neolithic expansions of people in several parts of the world starting 10,000 years ago.

“We think this second, previously unknown population boom, may have occurred as humans adapted to their new environment after the first out-of-Africa expansion,” says Dr Qasim Ayub, lead author from the Wellcome Trust Sanger institute. “We think that when humans moved from the horn of Africa to Asia, Australia and eventually Europe, they remained in small groups by the coasts. It took them tens of thousands of years to adapt to the mountainous, forested surroundings on the inner continents. However, once their genetic makeup was suited to these new environments, the population increased extremely rapidly as the groups travelled inland and took advantage of the abundance of space and food.”

The work highlights how it is now possible to obtain new biological insights from existing DNA sequencing data sets, and the value of sharing data. The majority of the DNA information used for this study was obtained from freely-available online data-sets.

This is the first time researchers have used the information from large-scale DNA sequencing to create an accurate family tree of the Y chromosome, from which the inferences about human population history could be made.

Full press release