Category Archives: Students

Items for students and others, interested in learning about science and engineering and the application of science in our lives. We post many of the general interest items here.

Global Installed Wind Power Now Over 1.5% of Global Electricity Demand

graph of global installed wind power capacity

Chart showing global installed wind energy capacity by Curious Cat Science and Engineering Blog, Creative Commons Attribution. Data from World Wind Energy Association, for installed Mega Watts of global wind power capacity.

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Globally 27,339 MW of capacity were added in 2008, bringing the total to 121,188 MW, a 29% increase. The graph shows the top 10 producers (with the exceptions of Denmark and Portugal) and includes Japan (which is 13th).

In 2007, Europe had for 61% of installed capacity and the USA 18%. At the end of 2008 Europe had 55% of installed capacity, North America 23%, Asia 20%, Australia 1.5%, Latin America .6% and Africa .5%. Country shares of global capacity at the end of 2008: USA 21%, Germany 20%, Spain 14%, China 10%, India 8% (those 5 countries account for 73% of global capacity).

USA capacity grew 50% in 2008, moving it into the global lead for the first time in a decade. China grew 107%, the 3rd year in a row it more than doubled capacity.

European Eels in Crisis After 95% Decline in Last 25 years

Eels in crisis after 95% decline in last 25 years

But the action the Environment Agency is about to take is upsetting those who rely on the eel for their livelihoods. A ban on exporting eels out of Europe – they are a popular dish in the far east – is proposed, along with a plan to severely limit the fishing season and the number of people who will be allowed licences.

It seems pretty obvious we have over-fished the oceans. Without effective regulation we will destroy the future of both the wildlife and our food source.

The eel remains one of the world’s most mysterious creatures. It is generally accepted that European eels – Anguilla anguilla – are born in the Sargasso Sea near Bermuda.

As leaf-like larvae, they are swept by the Gulf Stream towards Europe, a journey that may take a year. When the larvae reach the continental shelf they change into “glass eels” and in the spring begin to move through estuaries and into freshwater.

The animals develop pigmentation, at which point they are known as elvers and are similar in shape to the adult eel. Elvers continue to move upstream and again change colour to become brown or yellow eels.

When the fish reach full maturity – some can live to 40 and grow to 1m long – they migrate back to the ocean. Females are reported to carry as many as 10m eggs. They return to the Sargasso Sea, spawn and die.

Antigen Shift in Influenza Viruses

Antigenic shift is the process by which at least two different strains of a virus, (or different viruses), especially influenza, combine to form a new subtype having a mixture of the surface antigens of the two original strains.

Pigs can be infected with human, avian and swine influenza viruses. Because pigs are susceptible to all three they can be a breeding ground for antigenic shift (as in the recent case of H1N1 Flu – Swine Flu) allowing viruses to mix and create a new virus.

Continue reading →

New Largest Known Cave

photo of world's largest known cave, in Vietnam

The world’s largest cave

A British caving team believe they have discovered the world’s largest cave passage in the heart of the Vietnamese jungle. The rocky passage is 150metres long and measures a towering 200metres in height – seven times as high as the vaulted ceiling of York Cathedral.
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Called Hang Son Doong (Mountain River Cave) it is believed to be almost twice the size of the current record holder
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The cave was originally discovered in 1991 by a Vietnamese Jungle man called Ho Khanh. However Mr Spillane said no-one had entered if before because ‘it emitted a frightful wind and noise which was due to a large underground river’.

Friday Cat Fun #15: Curious Cat Hat

Maru, a Scottish Fold, in Japan has his own cat blog. This is a second post on Maru: Friday Cat Fun #7: Curious Cat and Boxes

Influenza Pandemic Alert Raised to Level 5 (of 6)

WHO Director-General, Dr Margaret Chan, announced today that she has “decided to raise the current level of influenza pandemic alert from phase 4 to phase 5.” And she further comments:

Let me remind you. New diseases are, by definition, poorly understood. Influenza viruses are notorious for their rapid mutation and unpredictable behaviour. WHO and health authorities in affected countries will not have all the answers immediately, but we will get them.

WHO will be tracking the pandemic at the epidemiological, clinical, and virological levels. All countries should immediately activate their pandemic preparedness plans. Countries should remain on high alert for unusual outbreaks of influenza-like illness and severe pneumonia.

At this stage, effective and essential measures include heightened surveillance, early detection and treatment of cases, and infection control in all health facilities.

I have reached out to companies manufacturing antiviral drugs to assess capacity and all options for ramping up production. I have also reached out to influenza vaccine manufacturers that can contribute to the production of a pandemic vaccine.

The biggest question, right now, is this: how severe will the pandemic be, especially now at the start?

It is possible that the full clinical spectrum of this disease goes from mild illness to severe disease. We need to continue to monitor the evolution of the situation to get the specific information and data we need to answer this question.

From past experience, we also know that influenza may cause mild disease in affluent countries, but more severe disease, with higher mortality, in developing countries.

No matter what the situation is, the international community should treat this as a window of opportunity to ramp up preparedness and response.

Above all, this is an opportunity for global solidarity as we look for responses and solutions that benefit all countries, all of humanity. After all, it really is all of humanity that is under threat during a pandemic.

As I have said, we do not have all the answers right now, but we will get them.
—- end of her remarks —-
The latest WHO Epidemic and Pandemic Alert and Response release puts the total number of confirmed cases at 148, in 9 countries, with 8 deaths. Mexico has many more suspected cases but just 26 confirmed cases. The CDC Swine Influenza site, puts the total number of confirmed cases in the USA at 91, in 10 states, with 1 death.

Lenz’s Law in Action: Eddy Current Tubes

Eddy Current Tubes — Drop the Magnets down the tube. An eddy current is set up in a conductor in response to a changing magnetic field. Lenz’s law predicts that the current moves in such a way as to create a magnetic field opposing the change; to do this in a conductor, electrons swirl in a plane perpendicular to the changing magnetic field.

Because the magnetic fields of the eddy currents oppose the magnetic field of the falling magnet; there is attraction between the two fields. Energy is converted into heat. This principle is used in damping the oscillation of the lever arm of mechanical balances.

Engineering Students Increasing at Universities

Engineering suddenly hot at universities

Across the United States, enrollment in engineering programs has risen to levels not seen in three decades. The recession appears to be one factor, as students and their parents look for dependable careers. But some education officials detect a shift in opinion about the profession itself, as global warming and stem-cell research make fields like chemical and bioengineering more than just wise choices for job-seekers – but fashionable ones, too.

Many students are bringing to engineering a heightened sense of social responsibility and a desire “to go out and make a difference in the world,” says Joseph Helble, dean of the Thayer School of Engineering at Dartmouth College in Hanover, N.H., where enrollment in introductory undergraduate courses is 30 percent above the five-year average.

Nationally, enrollment in undergraduate engineering programs rose 3 percent in 2007 and 4.5 percent 2008, according to the American Association of Engineering Education. Meanwhile, enrollment in masters’ degree programs rose 7 percent in 2007 and 2 percent in 2008. In the fall of 2008, 91,489 masters degree students and 403,193 undergraduates were studying engineering at US universities and colleges.

Skeptics note that engineering remains a low priority for US students: Among the 25 top engineer-producing countries, the United States ranks No. 22 on a per capita basis.

Increased engineering education is good news for future economic growth. Hopefully this trend can continue.

Swine Flu: a Quick Overview

World Health Organization on Swine influenza

After reviewing available data on the current situation, Committee members identified a number of gaps in knowledge about the clinical features, epidemiology, and virology of reported cases and the appropriate responses. The Committee advised that answers to several specific questions were needed to facilitate its work.

The Committee nevertheless agreed that the current situation constitutes a public health emergency of international concern.

Based on this advice, the Director-General has determined that the current events constitute a public health emergency of international concern, under the Regulations.

Swine flu: a quick overview–and new New York and Kansas cases by Tara Smith

while the cases in the US have been mild and no deaths have occurred that we’re aware of, it seems in Mexico that young people are dying from this–a group that is typically not hard-hit by seasonal influenza viruses. Readers familiar with influenza and know the history of the 1918 influenza pandemic will recall that the “young and healthy” were disproportionally struck by that virus as well–so this knowledge is currently disconcerting and worrisome, but there are so many gaps in our information as far as what’s really going on in Mexico that it’s difficult to make heads or tails out of this data right now.

Third, is this really a new virus? So few influenza isolates are actually analyzed each year (in proportion to the number of people infected) that we aren’t sure yet whether this is something brand-new, or something that has been circulating at a low level for awhile, but just hadn’t been picked up. After all, H1N1 is a common serotype, so additional molecular testing is needed to determine that it’s “swine flu” versus “human” H1N1.
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this is a fast-developing story, and it will take much more investigation and field work to determine the true extent of the virus’s spread in the population; to figure out… how efficiently it’s transmitted…

This is very early in the scientific inquiry process looking into what exactly is going on. It is too early to tell how serious a threat this is. The reaction of WHO, CDC though shows they are taking the threat seriously. By far the biggest danger in such situations, is reacting too slowly to serious and contagious threats. If you wait to react until proof exists that the situation is very serious the situation can be almost impossible to control. So you need to react quickly to shut down the spread of the threat, hopefully before it has spread too far.

Evolutionary Robotics

Evolutionary Robotics, chapter of Handbook of Robotics, is interesting and includes a good explanation of the difference between evolution and learning:

Evolution and learning (or phylogenetic and ontogenetic
adaptation) are two forms of biological adaptation that differ in space and time. Evolution is a process of selective reproduction and substitution based on the existence of a population of individuals displaying variability at the genetic level. Learning, instead, is a set of modifications taking place within each single individual during its own life time.

Evolution and learning operate on different time scales. Evolution is a form of adaptation capable of capturing relatively slow environmental changes that

might encompass several generations (e.g., the perceptual characteristics of food sources for a given species). Learning, instead, allows an individual to adapt to environmental modifications that are unpredictable at the generational level. Learning might include a variety of mechanisms that produce adaptive changes in an individual during its lifetime, such as physical development, neural maturation, variation of the connectivity between neurons, and synaptic plasticity. Finally, whereas evolution operates on the genotype, learning affects only the phenotype and phenotypic modifications cannot directly modify the genotype.
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Recent research showed that teams of evolved robots can: (a) develop robust and effective behavior, (b) display an ability to differentiate their behavior so
to better cooperate; (c) develop communication capabilities and a shared communication system.