Drug for deadly prostate cancer

Wednesday, July 23rd, 2008

Researchers have developed a new drug for deadly prostate cancer:

It had been assumed that the cancer was driven by sex hormones such as testosterone produced in the testicles.

Current treatments work by stopping the testicles from producing testosterone.

However, experts have now discovered that the cancer can feed on sex hormones from all sources, including supplies of the hormone produced by the tumour itself.

Abiraterone works by blocking production of the hormones throughout the body.

The latest study, published in the Journal of Clinical Oncology, is based on just 21 patients with advanced, aggressive prostate cancer treated with the drug — but data has been collected on a total of 250 worldwide.

It found significant tumour shrinkage, and a drop in tell-tale levels of a key protein produced by the cancer called prostate specific antigen in the majority of patients.

Many of the patients have reported a significant improvement in the quality of their lives.

Some were able to stop taking morphine for the relief of pain caused by the spread of the disease to their bones.

California adopts innovative solar loan law

Wednesday, July 23rd, 2008

California adopts innovative solar loan law:

The law, sponsored by Assemblyman Lloyd Levine (D- Van Nuys), allows cities and counties to make low-interest loans to homeowners and businesses to install solar panels, high-efficiency air conditioners and other improvements to save energy. Participants can pay back the loans as part of their property taxes. If they move, the improvements and loan balance are transferred to the next owner.

The financing scheme, if adopted by cities, is likely to give a statewide boost to the installation of solar panels to generate electricity. Solar power systems can cost between $15,000 and $30,000 — more than many homeowners can afford, although state rebates cover much of the cost. But with the loans, and the guarantee that the investment will not be lost when people sell their homes, the risk is dramatically reduced.

This might work for “green” technologies that actually make financial sense, like geothermal heat pumps, but which require big up-front investment — especially because consumers don’t yet know they make financial sense.

The Mystery of “b := (b = false)”

Wednesday, July 23rd, 2008

Stuart Reges explains The Mystery of “b := (b = false)” — and a few other “powerhouse questions” on the computer science advanced placement exam:

Most multiple-choice questions on the exam had few significant correlations with other parts of the exam. But a small set of five questions had a nontrivial correlation with many parts of the test. One question in particular demonstrated such correlations. It asked about the effect of the assignment statement “b := (b = false)” for a boolean variable b. One interpretation of this data is that these questions are testing general programming aptitude.
Computer Science educators have for years complained that introductory courses seem to be divided between a group of students who “get it” and a group of students who do not. Donald Knuth has written about this phenomenon:
“Educators of computer science have repeatedly observed that only about 2 out of every 100 students enrolling in introductory programming classes really resonate with the subject and seem to be natural-born computer scientists…I conclude that roughly 2% of all people ‘think algorithmically,’ in the sense that they can reason rapidly about algorithmic processes.”

It was an unpublished study conducted by Gerrit DeYoung in which he found that a measure of quantitative reasoning was not a predictor of success in a course for CS majors but was a reasonable predictor of success in a course for nonmajors. Knuth’s tentative conclusion was that there is some kind of CS aptitude that is not measured by standard tests of quantitative reasoning and that students who lacked that ability were instead relying on general quantitative aptitude.
What exactly do the powerhouse questions look like? Let’s explore question 23 in depth because it had the most nontrivial correlations. The exact text of the question is reproduced below:

23. If b is a Boolean variable, then the statement b := (b = false) has what effect?
(A) It causes a compile-time error message.
(B) It causes a run-time error message.
(C) It causes b to have value false regardless of its value just before the statement was executed.
(D) It always changes the value of b.
(E) It changes the value of b if and only if b had value true just before the statement was executed.

Only 5.4% of the students skipped the question. Of those who answered, 60% got it right. And getting this question right turned out to be a predictor of success on most of the rest of the exam, including solving complex problems like reversing a linked list.

To answer this question correctly, a student has to be able to read the code and simulate its execution. They also have to be able to identify the correct answer among the given choices.
So what do the powerhouse questions have in common? They all involve reading and understanding code. They all test whether students have a proper mental model of program execution. And they involve some of the most central concepts from the first year programming course: logic, recursion and two-dimensional arrays.

The author had the opportunity to present these results to a group of Stanford faculty, including the late Bob Floyd. Floyd, who had taught introductory programming many times, commented that the greatest single predictor he had noticed for success was whether students had a mental model of program execution, whether they could “play computer” in their head. He commented that these questions seemed to be very good at measuring that ability.
Knuth provides an intriguing intuition about this in talking about the difference between mathematical reasoning and algorithmic thinking:

“The other missing concept that seems to separate mathematicians from computer scientists is related to the ‘assignment operation’ :=, which changes values of quantities. More precisely, I would say that the missing concept is the dynamic notion of the state of a process. ‘How did I get here? What is true now? What should happen next if I’m going to get to the end?’ Changing states of affairs, or snapshots of a computation, seem to be intimately related to algorithms and algorithmic thinking.”

Question 23 is about assignment for a boolean variable that requires thinking about its value before the assignment statement and what value it will have afterwards.

Photographing thugs ‘is assault’, police tell householder snapping proof of anti-social behaviour

Wednesday, July 23rd, 2008

If this is true, the UK is self-destructing even faster than I realized. Photographing thugs 'is assault', police tell householder snapping proof of anti-social behaviour:

David Green, 64, and his neighbours had been plagued by the youths from a nearby comprehensive school for months, and was advised by their headmaster to identify them so action could be taken.

But when Mr Green left his £1million London flat to take photographs of the gang, who were aged around 17, he said one threatened to kill him while another called the police on his mobile.

And he claimed that a Police Community Support Officer sent to the scene promptly issued a warning that taking pictures of youths without permission was illegal, and could lead to a charge of assault.

Start-Up May Aid Telecoms’ Reach

Tuesday, July 22nd, 2008

A new start-up may aid telecoms' reach into developing nations with its low-energy base stations:

Some two billion new subscribers are projected to start using mobile phones in the next five years, and 80% of them live in developing-world markets, according to analyst estimates. Yet wiring villages without reliable electricity, and where residents have little money to spend, requires a technological rethink.

To power mobile networks in remote areas today, telecommunications operators pair base stations — the tower-top radio transmitters that form the backbone of mobile networks — with diesel-powered generators and batteries. These are impractical and expensive: Fuel accounts for 65% of the cost of operating a typical base station.

VNL, which has headquarters in New Delhi and Stockholm, has spent the past four years developing a simplified base station that is powered by solar panels and requires just a fraction of the electricity of typical base stations.
VNL’s base station will cost $3,500 and require 100 watts to run, about the same as a light bulb. By contrast, the GSM stations most widely used today can cost anywhere from $40,000 to $100,000. The most energy-efficient models require around 600 watts; others may need several thousand watts.

“We started with a clean sheet of paper, and told ourselves that we needed to design technology perfectly suited for the rural environment,” says VNL Chief Executive Anil Raj, a former executive at Ericsson.

The tower is designed to make it easy for people with little professional training to install. The equipment comes with a pictorial instruction manual similar to those for Ikea’s do-it-yourself furniture. It has just one button, used to turn it on. Once the pole is erected, the base station beeps intermittently until the radio antenna is rotated manually to face the direction of the mobile network. When the antenna is perfectly aligned, the sound steadies.

Toy rocket inspires variable-speed bullets

Tuesday, July 22nd, 2008

Toy rocket inspires variable-speed bullets:

Lund and Company Invention, a toy design studio based near Chicago, makes toy rockets that are powered by burning hydrogen obtained by electrolysing water. Now the company is being funded by the US army to adapt the technology to fire bullets instead.

The US Army are interested in arming soldiers with weapons that can be switched between lethal and non-lethal modes. They asked Company Invention to make a rifle that can fire bullets at various speeds.

The new weapon, called the Variable Velocity Weapon System or VWS, lets the soldier to use the same rifle for crowd control and combat, by altering the muzzle velocity. It could be loaded with “rubber bullets” designed only to deliver blunt impacts on a person, full-speed lethal rounds or projectiles somewhere between the two.

Bruce Lund, the company’s CEO, says the gun works by mixing a liquid or gaseous fuel with air in a combustion chamber behind the bullet. This determines the explosive capability of the propellant and consequently the velocity of the bullet as it leaves the gun. “Projectile velocity varies from non-lethal at 10 metres, to lethal at 100 metres or more, as desired,” says Lund.

The company says that the weapon produces less heat and light than traditional guns. It can also be made lighter and could have a high power setting for long-range sniping.

Police already fire non-lethal projectiles from standard shotguns. These are known as “beanbag” rounds, bags of lead shot which will knock down a suspect at ranges of up to 10 metres. They are termed “non-lethal”, but can cause bruising or even broken ribs.

Some Athletes’ Genes Help Outwit Doping Test

Monday, July 21st, 2008

In a Swedish study, 55 men were given testosterone injections and then given the standard drug test. Most of the men tested positive, but 17 did not.

Some Athletes’ Genes Help Outwit Doping Test:

Those 17 men can build muscles with testosterone, they respond normally to the hormone, but they are missing both copies of a gene used to convert the testosterone into a form that dissolves in urine. The result is that they may be able to take testosterone with impunity.

The gene deletion is especially common in Asian men, notes Jenny Jakobsson Schulze, a molecular geneticist at the Karolinska University Hospital in Stockholm. Dr. Schulze is the first author of the testosterone study, published recently in The Journal of Clinical Endocrinology and Metabolism.

Dr. Schulze learned from an earlier study that about two-thirds of Asian men are missing both copies of the gene, as are nearly 10 percent of Caucasians. The prevalence in other groups is not known.
The gene in question adds a chemical, glucuronide, to testosterone. That converts it from a substance that dissolves in oil into one that dissolves in water and urine.
The men with two normal copies of the gene had T [testosterone] to E [epitestosterone] ratios that soared to 100; those with one copy of the gene had ratios that reached 50; those with no copies had almost no rise in their ratios and 40 percent of them had a ratio that never reached 4.

So the gold medal goes to the guy who’s genetically untestable? Great.

(Hat tip to Educated Guesswork.)

Drug restores speech in Alzheimer’s; experts worry

Monday, July 21st, 2008

An anti-inflammatory rheumatoid arthritis drug restores speech in Alzheimer's patients, but experts worry that the small, not-so-rigorous study may give people false hope:

The study, reported on Sunday in the journal BioMed Central BMC Neurology, involved 12 patients who had greatly improved language recall shortly after treatment with Enbrel, or etanercept, an anti-inflammatory drug co-marketed by Amgen and Wyeth.
Tobinick believes the drug may work in the brain by blocking an excess of tumor necrosis factor-alpha or TNF-alpha, which may affect communication in the brain.
Tobinick acknowledged the study is limited because people knew they were getting the drug. Alzheimer’s patients in such open-label studies often show improvement.

“Placebo effect is an enormous problem in open-label studies,” said Dr. Scott Turner, incoming director of the Memory Disorders Program at Georgetown University Medical Center in Washington.

Turner said the true test must come from a more scientifically rigorous double-blind, placebo-controlled, randomized clinical trial. In such studies, patients receive either a dummy treatment or an active agent, and neither the doctor nor the patient knows which.

Forecasting Oil Prices: It’s Easy to Beat the Experts

Monday, July 21st, 2008

When it comes to forecasting oil prices, it’s easy to beat the experts — because the market’s already done the work for you:

At least this is what I learned from a recent working paper, “What Do We Learn From the Price of Crude Oil Futures?” by Michigan economists Ron Alquist and Lutz Kilian.

The authors compare a whole range of different ways of forecasting oil prices: they look up the Consensus Forecast (from a survey of expert economic forecasters), oil futures, the difference between the oil price in futures and spot markets, and also a range of more or less complicated econometric models that take account of recent trends, as well as variables like the interest rate.

And it turns out that they all do worse than one simple forecast: the current oil price. That’s right: the most accurate forecast of oil prices over the next month, year, or quarter is the current oil price. We call this the no-change forecast.

Give me your tired, your poor…doctoral candidates

Monday, July 21st, 2008

If you are a PhD student in America, The Economist notes, there’s a good chance that your undergraduate degree came from Tsinghua University in China. “That’s because Tsinghua and Peking Universities are now the top feeder schools for American PhD programmes”:

American students who do have the skills necessary for a quantitative PhD might also be less likely to pursue graduate work, because these skills are in high demand. A clever graduate with strong quantitative skills can fetch a high salary right out of university. The alternative of seven years of indentured servitude to your adviser probably sounds less appealing to many recent graduates.

Students from China do not face such high-paying alternatives at home. Also, now that the number of H2 visas for skilled labour has decreased, PhD programmes provide a path to America for some. This helps explain why the number of foreign students in PhD programmes increased remarkably between 2001 and 2006. After completing their studies, most foreign-born students hope to stay in America.

Kim’s Game

Friday, July 18th, 2008

I didn’t realize that the jewel game from Kipling’s Kim had been dubbed Kim’s Game and popularized in real life:

Kim, a teenager being trained in secret as a spy, spends a month in Simla, India at the home of Mr. Lurgan, who ostensibly runs a jewel shop but in truth is engaged in espionage for the British against the Russians. Lurgan brings out a copper tray and tosses a handful of jewels onto it; his boy servant explains to Kim:
Look on them as long as thou wilt, stranger. Count and, if need be, handle. One look is enough for me. When thou hast counted and handled and art sure that thou canst remember them all, I cover them with this paper, and thou must tell over the tally to Lurgan Sahib. I will write mine.

They contest the game many times, sometimes with jewels, sometimes with odd objects, and sometimes with photographs of people. It is considered a vital part of training in observation; Lurgan says:

[Do] it many times over till it is done perfectly — for it is worth doing.

In his book Scouting Games, Robert Baden-Powell, the founder of scouting, names the exercise Kim’s Game and describes it as follows:

The Scoutmaster should collect on a tray a number of articles — knives, spoons, pencil, pen, stones, book and so on — not more than about fifteen for the first few games, and cover the whole over with a cloth. He then makes the others sit round, where they can see the tray, and uncovers it for one minute. Then each of them must make a list on a piece of paper of all the articles he can remember… The one who remembers most wins the game.

Preferring a Pound of Cure

Thursday, July 17th, 2008

Voters prefer a pound of cure to an ounce of prevention, Bryan Caplan notes, citing Andrew Healy‘s recent paper:

Using comprehensive data on natural disasters, government spending, and election returns, I show that voters reward disaster relief spending but not disaster prevention spending. This aspect of voter behavior creates a large distortion in the incentives that governments face, since the data show that prevention spending substantially reduces future damage.
Given mean annual prevention spending of $195 million and mean disaster damage of $16.5 billion, the regression estimates that a $1 increase in prevention spending resulted in a $8.30 decrease in disaster damage, and this estimate captures only benefits that occur in the five years from 2000-2004.

Africa is giving nothing to anyone — apart from AIDS

Thursday, July 17th, 2008

Irish write Kevin Myers speaks the unspeakable, and says that Africa is giving nothing to anyone — apart from AIDS:

No. It will not do. Even as we see African states refusing to take action to restore something resembling civilisation in Zimbabwe, the begging bowl for Ethiopia is being passed around to us, yet again. It is nearly 25 years since Ethiopia’s (and Bob Geldof’s) famous Feed The World campaign, and in that time Ethiopia’s population has grown from 33.5 million to 78 million today.

So why on earth should I do anything to encourage further catastrophic demographic growth in that country?
Sorry. My conscience has toured this territory on foot and financially. Unlike most of you, I have been to Ethiopia; like most of you, I have stumped up the loot to charities to stop starvation there. The wide-eyed boy-child we saved, 20 years or so ago, is now a priapic, Kalashnikov-bearing hearty, siring children whenever the whim takes him.
Within 20 years of the [Irish] Famine, the Irish population was down by 30 [percent]. Over the equivalent period, thanks to western food, the Mercedes 10-wheel truck and the Lockheed Hercules, Ethiopia’s has more than doubled.

Alas, that wretched country is not alone in its madness. Somewhere, over the rainbow, lies Somalia, another fine land of violent, Kalashnikov-toting, khat-chewing, girl-circumcising, permanently tumescent layabouts.

Indeed, we now have almost an entire continent of sexually hyperactive indigents, with tens of millions of people who only survive because of help from the outside world.
How much morality is there in saving an Ethiopian child from starvation today, for it to survive to a life of brutal circumcision, poverty, hunger, violence and sexual abuse, resulting in another half-dozen such wide-eyed children, with comparably jolly little lives ahead of them? Of course, it might make you feel better, which is a prime reason for so much charity. But that is not good enough.

For self-serving generosity has been one of the curses of Africa. It has sustained political systems which would otherwise have collapsed.

It prolonged the Eritrean-Ethiopian war by nearly a decade. It is inspiring Bill Gates’ programme to rid the continent of malaria, when, in the almost complete absence of personal self-discipline, that disease is one of the most efficacious forms of population-control now operating.

If his programme is successful, tens of millions of children who would otherwise have died in infancy will survive to adulthood, he boasts. Oh good: then what?

(Hat tip to Dennis Mangan.)

The Depressive Realism Economy

Thursday, July 17th, 2008

Arnold Kling calls it The Depressive Realism Economy:

There are psychologists who argue that healthy people tend to have an inflated view of their abilities and how they are regarded by peers. In contrast, these psychologists contend, there is a tendency for depressed people to accurately assess where they stand. This hypothesis is called “depressive realism.” It explains our current economic gloom.
It now appears that we were living in a dream world a few years ago, with oil prices unsustainably low and house price inflation unsustainably high. Reality is less pleasant.

In theory, a student who suffers a blow to his or her self-esteem can continue to work hard and learn. In practice, educators worry that this will not happen.

Similarly, the asset revaluations that represent blows to our economic self-esteem could be shrugged off by workers and businesses. We still have all of the capital equipment and know-how for the U.S. economy to continue growing.

However, a significant reallocation of resources is required. For example, we need fewer construction workers. During the boom, the housing stock grew faster than the rate of family formation. It will take several years for this excess housing inventory, which some economists estimate may be as much 3 million units above its normal level, to be occupied.

Educational credentials that seemed useful four years ago may not be as valuable during the current transition phase.

Kling sees the problem through the unorthodox lens of macro without aggregate demand:

Orthodox Keynesian macroeconomics says that the cure for economic pessimism is for government to create an illusion. Congress can cut taxes or the Federal Reserve can print money in order to make people feel more prosperous.

What government cannot do, however, is figure out how to reallocate workers to new industries in a way that reflects long-term reality. Government does not know whether the journalism graduate should wait patiently for a relevant job or whether he needs to find a different career path.

Adapting to the reality of higher energy costs and an excess housing stock requires myriad complex adjustments, some of which may be obvious but many of which are subtle. Chances are, it will take several years to complete the transition. Meanwhile, there is little, if anything, that policymakers can do to hasten that process.

Rampage on the Rampage

Wednesday, July 16th, 2008

Apparently Quinton “Rampage” Jackson went on a second-rate rampage outside the cage, in his “lifted” Ford F-250 truck, emblazoned with his photo:

Rampage was on the 55 Freeway in the O.C., hit two cars and got off the freeway. The chase was on.

Rampage then began driving on the center divider. But it gets worse. According to the police report, Jackson then drove on the sidewalk, “causing pedestrians to flee for their lives.” He started driving the wrong way on a crowded street, colliding with yet another car in an intersection. As he continued on, running several red lights, his tire disintegrated and he began driving on the rim.

Rampage eventually got to the exclusive Balboa Peninsula in Newport Beach, where he again drove on the sidewalk, “causing pedestrians to flee in terror.”

Eventually, his car came to a stop and he was taken into custody at gunpoint. Cops took him to the Orange County Jail, but they determined he was “medically unfit” to be booked. Cops won’t say if he was high.

Rampage is currently in an O.C. hospital.

Quinton, Quinton, Quinton…