David Bradley – Page 294

Possums, horses, and pigs do it

Brushtail possums, photo by wollombi http://www.flickr.com/photos/wollombi/ I just received an early publication alert from the Australian research organisation CSIRO announcing the imminent publication of volume 19 of their journal on reproductive science, fascinating I thought as I opened the attachment.

First up in the list of contents was a paper that sounded rather intriguing from FC Molinia and colleagues entitled: “Uterine and vaginal insemination optimised in brushtail possums (Trichosurus vulpecula) superovulated with pregnant mare serum gonadotrophin and porcine luteinising hormone”.

So, let us just dissect what that convoluted title actually means. Basically, they stimulated brushtail possums with hormones from a horse and a pig to make it produce more eggs than normal and then artificially inseminated the females, with brushtail possum sperm, obviously. I am pretty sure it is all standard procedure for getting those little brushtails up the duff, and it is not so odd that they used horse hormones in the process, after all, one form of human hormone replacement therapy uses equine estrogen.

Something worries me a lot about this particular EarlyAlert. The abstract says that artificial insemination of brushtail possums (Trichosurus vulpecula) is being developed as an assisted breeding model for endangered marsupials, as well as a bioassay for testing fertility control vaccines to manage overabundant populations.

Hmmm…humans do not have a strong record on “assisting” animals in this way, and particularly not in Australia, I am thinking rabbits and mixomatosis, feral camels, and the infamous cane toad, to name but three. Why is it that we feel we can intervene and manage ecosystems in this way? The end results are usually disastrous and given the purportedly fragile nature of Australia’s ecosystems, should we not leave well alone?

The full paper can be accessed here.

Smog masks at the ready

Smog mask by zoonabar The gist of a recent press release regarding research into alternative fuels for reducing the environmental impact of transport and helping us head towards a sustainable transport system said that there is basically no single alternative fuel that could provide all the answers. The research in question, published in the International Journal of Alternative Propulsion drew up a league table of alternative fuels that placed petrol (gasoline) and diesel at the bottom in terms of their negative environmental impact, closely followed by hybrid liquid gas driven vehicles. Surprisingly, at the top of the league table was the use of hydrogen fuel cells running on hydrogen obtained from converted methane. Surprising because one would assume that the use of methane, or natural gas, would have such an environmental impact as to push it down the league table and moreover be unsustainable.

The study’s authors, Karl HÃ¸yer of Oslo University College, Norway and Erling Holden of the Western Norway Research Institute, do concede, as is mentioned in the press release, that there is no alternative fuel that is 100% sustainable and has a zero carbon footprint. That is perhaps inevitable. However, there is research being undertaken that would suggest that natural gas is not the limited fossil fuel we might think. Indeed, there are vast reserves that are apparently produced by bacterial activity that might feed the league-topping fuel cells mentioned in HÃ¸yer and Holden’s paper.

One commentator, John Zerbe of the USDA Forest Service, in Madison, Wisconsin, was not convinced that the HÃ¸yer and Holden league table was valid at all. This is what he had to say on the matter:

“I think the most significant conclusion from the Norwegian scientists’ work is that currently there is no consensus regarding sustainable transport development. They obviously considered the relative importance of energy use, carbon dioxide emissions, and nitrogen oxide pollution differently than I would have. There is no way that I would rank fuel cell powered vehicles using hydrogen gas obtained from natural gas methane at the head of the list.”

Granted, fuel cell powered vehicles should be efficient. Chevron has stations that dispense hydrogen made, mostly, from natural gas. So, energy use with the fuel cell vehicle powered by hydrogen should be good and there is probably no nitrogen oxide pollution.

However, until Chevron has some experience, it is hard to know what the hang-ups will be. Use of fossil natural gas will certainly be bad for global warming. It is already conceded that hydrogen isn’t amenable to long distance transportation. So Chevron makes hydrogen close to where it is being used. Imagine the difficulties in filling a fuel tank on a vehicle with 5000 psi hydrogen. It seems impossible that they could prevent all leaks, and hydrogen at 5000 psi is probably more prone to explosion than gasoline or diesel at atmospheric pressure.”

Zerbe suggests that the best well-to-wheel evaluation would have to take into account a complete lifecycle analysis. Energy use would certainly be important in such an analysis, but a lifecycle analysis could be weighted so that generally more acceptable limitations, such as the unsustainable nature of fossil fuel natural gas is considered a more negative factor.

Bioethanol Boom or Bust

Ethanol structure Bioethanol, or strictly speaking cellulose-derived ethanol is fast becoming the front-runner in efforts to reduce our reliance on oil. There are problems associated with its production, not least issues of water supply and the environmental impact. The high production cost remains one of the biggest obstacles.

Now, researchers at Baylor University have identified forty different compounds formed in the pre-treatment step when making cellulosic ethanol that could be responsible for inhibiting the fermentation process, their elimination might reduce overall production costs and make this form of biofuel more economically viable.

“We screened for forty compounds, like phenols and organic acids, and they were all present,” said Kevin Chambliss, “We chose these particular compounds because they are believed to be inhibitory, but other compounds could be involved too.”

While conventional ethanol and cellulosic ethanol are essentially the same product, the two are made from different feedstocks. Conventional ethanol is produced from grains such as corn and wheat. Cellulosic ethanol is made from the non-food portion of many agricultural wastes. One of the more common wastes used is corn stover, which are the stalks and residue left over after harvest. Researchers said there has been a recent emphasis on learning more about cellulosic ethanol because agricultural wastes are mostly an untapped resource.

“If you can identify a pre-treatment condition that maximizes sugar production, yet minimizes inhibitor production, that could increase efficiency better than just removing the compound,” adds team member Peter van Walsum. The team will be testing softwood feedstocks, such as Dougas fir trees next.

InChI=1/C2H6O/c1-2-3/h3H,2H2,1H3

Matrix recharged

Matrix recharged One of the big problems facing society in its search for sustainable alternative energy sources is not how to harness wind, solar, or wave power, but how to store the electricity produced using these elements at times of low demand. Capacitors could be the answer. These devices can be charged up very quickly, store electrical energy for long periods, and then be discharged rapidly for a range of applications. Such capacitors are on the horizon but their small-scale cousins are developing even more rapidly for portable applications. Find out more in the May issue of Intute Spotlight.

Also under the Spotlight this month, Norwegian scientists have drawn up a league table of alternative fuels for cars based on what they call a “well-to-wheel” analysis. Their approach takes into account the energy costs in manufacturing, total energy use, and overall pollution included greenhouse gas emissions. Unsurprisingly, petrol and diesel vehicles foot the table, closely followed by hybrid vehicles. In contrast, the greenest way to power a vehicle turns out to be to use an electric fuel cell powered by hydrogen made from natural gas, methane.

Finally, in the 1950s, the atomic clock was the pinnacle of split-second time-keeping. Today, physicists use its successors based on energy transitions in rubidium atoms that gives them 100 times more accuracy. These clocks currently operate at their theoretical limit but nevertheless are accurate to one second every 50 million years. Quantum noise, the random fluctuations of atoms and ions and the grim truth of Heisenberg’s Uncertainty Principle would probably mean no improvements for the next 50 million years.

DBPedia for Chemists

Cambridge chemist Peter Murray-Rust recently alerted me to the DBpedia service. DBpedia.org is a community effort to extract structured information (semantics) from Wikipedia and to make this information available on the Web. DBpedia allows you to ask sophisticated questions of Wikipedia rather than carrying out simple searches. “DBPedia is a semantic distillate of Wikipedia and soon all the chemistry will be in semantic form,” asserts Murray-Rust, “It will then be possible to ask questions like: “find compounds which were discovered by a Russian chemist in the 19th Century”. That is a simplistic example, of course. He believes that such efforts form part of a new information philosophy of linked data and points out that Open chemical resources, such as Pubchem, DBPedia, CrystalEye, ChEBI, etc. will soon become part of that philosophy.

Chemspy Blog Archived

Having run the Chemspy RSS feed manually for rather too long, we have finally upgraded to a CMS that enables a much slicker interface and will hopefully benefit readers considerably by providing easier access to the site news and our new chemistry news section. As such, earlier ChemSpy posts have now been archived as a standalone static page and can be accessed through the Chemspy chemistry news archives page here.

UPDATE: All chemistry items that would have originally been earmarked for inclusion in Chemspy will now appear in Sciencebase.com

Straight answers to health questions

Anahad O'Connor NYT reporter Anahad O’Connor sent me a review copy of his latest book, “Never shower in a thunderstorm”, which hits bookshelves in paperback this week. In it, O’Conner debunks, in the style of his regular “Really?” column, numerous health myths and misconceptions such as whether artificial light is hazardous to health, are bald men more virile (of course!), and is chicken soup good for treating the common cold?

Here’s a selection from his book, with the most straightforward answer I could extract from his excellent vignettes.

Can a glass of wine with your meal prevent food poisoning? Yes
Are ab machines the best way to build a six-pack? No
Will having sex before sports hinder your performance? No
Can having sex induce labour? No
Is yo-yo dieting unhealthy? Yes
Is bottled water cleaner than tap? No
Does packing a wallet in your back pocket cause sciatica? Yes
Do toilet seats spread disease? No
Is sitting up straight good for your back? No
Can loud music deafen you? Yes

If you want the complete explanation for his answers to these questions and many more, you will, of course, have to read the book.

Broken laptop again

UPDATE: July 2013 That Vostro is now starting to fail. A few sticky broken keys, RAM damaged, GPU failing and hard drive errors. Already replaced battery once since Dell engineer came (they don’t last long, batteries, not Dell engineers!) Mistake or not, latest Dell Vostro on the way i7 chip, but 15″ not 17″ save a few quid!

As regular visitors to Sciencebase know, our individual posts are entirely independent of advertisers. However, for a time the site had its own coupons and discounts section, which helped support us financially; back then we were getting 20000 unique visitors every single day! At the time of writing, I was using a Dell Vostro 3700 (chosen primarily because it was one of the only laptops around at the time with a matte screen) and although I had to have it serviced at about 18 months because of a faulty fan, it’s been fine. The service engineer replaced the fan, the motherboard and the battery all under warranty and in my own home within an hour or two.

My previous working machine was a 17″ HP Pavilion, for those who care about knowing such things! Before that I’d had another Dell Inspiron, a Gateway desktop, an Evesham Micros desktop, an Acer laptop before that and a homebuilt desktop. My first home office machine was from local company Solidisk who changed their name years ago to World of Computers, that machine had a 40 megabyte hard drive, can you imagine that? Space for two or three RAW file photos from my Canon 20D digital SLR!

Agony agonists and cancer combatants

In chemistry news this week, The Alchemist learns about slow-release drug formulations that prevent drug abuse, the risks of war associated with using depleted uranium in munitions and armour plating, and the analytical benefits of red wine that could turn up on labels to guide consumers to the most healthful Chianti or Zindanfel.

Also, this week, a well to wheel analysis reveals that hybrid cars are not as green as you would think and that converting natural gas to hydrogen for use in fuel cells could be the best environmental option for transport. Finally, web-savvy chemists using the Firefox browser have a new tool available to them that offers inline entries from blogs while they read ACS, RSC, Wiley, and other journal tables of contents.

This week’s grant goes to Bassam Shakhashiri for pioneering work in engaging the public with science and for helping to rebuild education programs after decimation by Reagan funding cuts in the 1980s.

Baby Boomers Should Choose Baby Aspirin

Aspirin structure A daily dose of aspirin could save you from a heart attack or stroke, but almost a quarter of a million Americans could be hospitalized each year because of gastric bleeding – a complications of taking the drug.

A study by cardiologists at the University of Kentucky College of Medicine, the Institut de Cardiologie-Centre Hospitalier Universitaire PitiÃƒÂ©-SalpÃƒÂªtriÃƒÂ¨re in Paris, France, and the UK HealthCare Linda and Jack Gill Heart Institute have found that the commonly prescribed 325 mg adult tablet is a lot more than most people will need to reduce their risk of cardiovascular disease each day. Their findings published in the Journal of the American Medical Association, suggest that an infant dose of aspirin, containing around 80 mg of the active ingredient is adequate for preventing cardiovascular events in the long-term and has the advantage of a much lower risk of gastrointestinal bleeding.

The researchers carried out a meta review of published clinical studies data on aspirin use and found no large-scale studies that supported higher doses of aspirin, even for patients with diabetes who are tougher to treat.

“While aspirin is an effective drug for the prevention of clots,” says lead author Charles Campbell, “the downside of aspirin therapy is an increased tendency for bleeding. We believe the minimum effective dose should be utilized (75-81 mg).” He cautions that this is a ballpark figure and the optimum dose should be considered on a patient by patient basis.

Aspirin is the oldest “manufactured” and most commonly used drug in the world. More than 50 million people, or 36 percent of the adult population in the United States, consume 10 to 20 billion aspirin tablets each year as a prophylactic against heart attack and stroke.

“Patients should check with their doctor to be sure, but there is almost no one who needs to take more than 81 mg of aspirin a day for protection from heart attacks,” adds co-author Steven Steinhubl.

What strikes me as odd about the press release that announced these findings is the precision in the milligram values given. A drop from 325 mg to 75-81 mg comes with unnecessary precision. that additional 1 mg is less than a third of a percent of the original mass and probably way below the weight tolerances available during the manufacturing process in the first place. Moreover, many patients are told to break a whole tablet in half and take just half a day, so any kind of precision in weight measurements is lost instantly as those tablets crumble and fragments containing perhaps several milligrams of aspirin are lost.

Also in the news this week and somewhat conflicting with Steinhubl’s recommendations is the discovery that at least 300 mg of aspirin taken daily might help prevent colorectal cancer. Peter Rothwell of the University Department of Clinical Neurology, at the Radcliffe Infirmary in Oxford, UK, suggest that the benefits of taking such a large dose of aspirin in the long term outweigh the risks associated with gastrointestinal bleeding for those at high risk, such as individuals with a strong family history of the disease or other factors. This second study is published in The Lancet today, more details in the original press release.

InChI=1/C9H8O4/c1-6(10)13-8-5-3-2-4-7(8)9(11)12/h2-5H,1H3,(H,11,12)/f/h11H