Showing posts with label Science. Show all posts
Showing posts with label Science. Show all posts

Sunday, March 15, 2009

Reseach on How to Improve Individual Decesions

Herd mentality. Angry mob. Mass hysteria. As these phrases suggest, we are not always confident that a large group of people will come up with the smartest decisions. So it may be surprising to learn that numerous studies have shown that a crowd of people usually gives more accurate responses to questions compared to a mere individual.

Averaging the responses provided from a group increases accuracy by canceling out a number of errors made across the board (such as over- and under-estimating the answer).

What happens when we are on our own? What if there is no one else around to consult with before making a judgment - how can we be confident that we are giving a good answer? Psychologists Stefan M. Herzog and Ralph Hertwig from the University of Basel wanted to know if individuals could come up with better answers using a technique they designed and called "dialectical bootstrapping."

Dialectical bootstrapping is a method by which an individual mind averages its' own conflicting opinions, thus simulating the "wisdom of the crowd." In other words, dialectical bootstrapping enables different opinions to be created and combined in the same mind. For example, in this study, participants were asked to identify dates of various historical events. After they gave their initial answer, the participants were asked to think of reasons why the answer may be wrong and were then asked to come up with an alternative second (dialectical) answer.

The results, reported in Psychological Science, a journal of the Association for Psychological Science, reveal that the average of the participants' first answer with the second answer was much closer to the correct answer, compared to the original answers on their own. In addition, the dialectical bootstrapping method (that is, thinking about why your own answer might be incorrect and then averaging across estimates) resulted in more accurate answers compared to simply making a second guess without considering why the first answer may be wrong.

These findings suggest that dialectical bootstrapping may be an effective strategy in helping us come up with better answers to many types of problems. The researchers note that while it may be frustrating going back and forth between two different answers, "as dialectical bootstrapping illustrates, being of two minds can also work to one's advantage." They conclude, "Once taught about the tool, people could make use of it to boost accuracy of their estimates across a wide range of domains."

Monday, February 9, 2009

9 Tips to Stop Snoring

Snoring is a fairly common affliction, affecting 40 percent of men and 25 percent of women. If you snore, you make a raspy, rattling, snorting sound while you breathe during sleep. Older people are particularly prone to snoring: About one-third of people ages 55 to 84 snore. Despite its frequency, however, snoring is a sleep disorder that can have serious medical and social consequences. The tips that follow may help you sleep more peacefully.

1. Sleep on Your Side
You're more likely to snore if you're lying on your back, and sleeping on your stomach is stressful on your neck.

2. Lose Weight
Excess body weight, especially around the neck, puts pressure on the airway, causing it to partially collapse.

3. Avoid Alcohol and Tranquilizers
Both alcohol and sleeping pills can depress your central nervous system and relax the muscles of your throat and jaw, making snoring more likely. These substances are also known to contribute to sleep apnea, a dangerous condition that has been linked with cardiovascular disease. And they should never, ever be used together. If you have difficulty sleeping without sleeping pills (or if you use alcohol to help yourself fall asleep), discuss it with your doctor.

4. Get Your Allergies Treated
Chronic respiratory allergies may cause snoring by forcing sufferers to breathe through their mouths while they sleep. Taking an antihistamine just before bedtime may help. If your nose is stuffed up, try using an over-the-counter saline spray or a humidifier.

5. Buy a Mouth Guard
Your dentist or doctor may be able to prescribe an antisnoring mouth guard that holds the teeth together and keeps the lower jaw muscles from becoming too lax.

6. Stop Smoking Smoke damages the respiratory system.

7. Keep a Regular Schedule Get plenty of sleep.
Go to bed and get up at the same time each day.

8. See a Doctor if You Are Pregnant and Snoring
Sometimes, women who are pregnant will begin to snore. The snoring may begin because of the increased body weight and because the hormonal changes of pregnancy cause muscles to relax. Whatever the cause, snoring during pregnancy may rob your baby of oxygen. Talk with your doctor about it.

9. Elevate Your Head
Sleeping with your head raised may take some of the pressure off of the airway, making breathing easier. Raise the head of the bed by putting blocks under the bed posts, or prop up your upper body (not just your head, which can actually inhibit breathing) with pillows.

Global Impact of Climate Change on Biodiversity

When three undergraduates set off on an expedition in 1965 to trap moths on Mount Kinabalu in Borneo, little did they realise that they were establishing the groundwork for a study of the impacts of climate change.

New research led by the University of York has repeated the survey 42 years later, and found that, on average, species had moved uphill by about 67 metres over the intervening years to cope with changes in climate.

This is the first demonstration that climate change is affecting the distributions of tropical insects, the most numerous group of animals on Earth, thus representing a major threat to global biodiversity.

University of York PhD student I-Ching Chen – first author of the new study – said:
“Tropical insects form the most diverse group of animals on Earth but to-date we have not known whether they were responding to climate change. The last Intergovernmental Panel on Climate Change AR4 Report showed a gaping hole in the evidence. Our new study is good in that it increases the evidence available, but it is potentially bad for biodiversity.”


Professor Thomas added:
“Large numbers of species are completely confined to tropical mountains, such as Mount Kinabalu: many of the species found by the expeditions have never been found anywhere else on Earth. As these species get pushed uphill towards cooler conditions, the amount of land that is available to them gets smaller and smaller. And because most of the top of the mountain is bare rock, they may not be able to find suitable habitats, even if the temperature is right. Some of the species are likely to die out.”


The New Expedition in 2007 was joined by Henry Barlow, one of the members of the original survey, whose life-long enthusiasm for moths helped I-Ching Chen, who is from Taiwan, to come to terms with the sheer diversity of moths she had to identify.

Jeremy Holloway, a Research Associate at the Natural History Museum in London, and another member of the 1965 expedition, devoted his career to the identification (taxonomy) of moths from South East Asia, enabling the research team to identify the new samples. Armed with the data from 1965, moth-trapping equipment, tents, sleeping bags and rations, I-Ching and colleagues set out to repeat the original survey.

“Photographs from the 1965 expedition led us back to exactly the same sites sampled 42 years ago”,

said Dr Suzan Benedick, expedition member, and Universiti Malaysia Sabah entomologist.

The new survey involved climbing the mountain and catching moths up to an elevation of 3,675 metres above sea level. Once all of the specimens had been caught and identified, then the team compared the heights at which each species had been found in 1965 and again in 2007. The results revealed a highly statistically significant shift, indicating that the moths are now found higher on the mountain than previously.

There is a more positive note, however. As the highest and coolest location between the Himalaya and New Guinea, Mount Kinabalu represents an extremely important “climate change refuge”. Species that begin to find conditions too hot (or dry) in the surrounding lowlands may be able to find suitable conditions by moving upwards on the slopes of this mountain.

“The critical thing is to protect the forests surrounding the mountain, so that the lowland species are able to reach the cooler conditions that they may need,”

said Dr Jane Hill, expedition member, and one of I-Ching Chen’s advisors.

Sunday, February 8, 2009

Jasmine- As an Anti-Cancer Agent

Professor Eliezer Flescher, of Tel Aviv University, and his colleagues have developed an anti-cancer drug based on a decade of research into the commercial applications of the compound Jasmonate, a synthetic compound derived from the Jasmine flower. Professor Flescher began to research the compound about a decade ago, and with his recent development of the drug, his studies have now begun to bear meaningful fruit.

Acetsalicylic acid (aspirin) is based on a plant stress hormone, which has been suggested by various studies, could prevent cancer, especially colon cancer. This provides an impetus to the researcher team to find a potent plant hormone that could fight cancer even better and they pinpointed jasmonate.

Both blood cancers and solid tumors seem to be responsive to the jasmonate compound, known also as methyl jasmonate. Professor Flescher is hopeful that an anti-cancer drug based on jasmonate could be on the shelf in America within four years through the activity of Sepal-Pharma which licensed his research from Ramot, the technology transfer arm of Tel Aviv University.

The jasmonate compound is used widely in agriculture and cosmetics. Proven to be non-toxic, it has the same regulatory status as table salt. It gives a good starting point for launching a new drug to the researcher team.

Dr. Flescher research receives optimistic response from peer researchers, who are taking notice. Since Professor started publishing papers on jasmonate (most recently in academic journal Oncogene), six new research groups around the world have initiated research on the subject. Peer commentary in Oncogene is positive about Professor Fleischer’s promising research. They comment that

“Methyl Jasmonate has already been shown to have selective anti-cancer activity in preclinical studies, and this finding may stimulate the development of a novel class of small anti-cancer compounds.”

Preparing For Climate Change

The global climate is changing, and this change is already impacting food supply and security. People living in regions already affected by aridity need plants that can thrive / grow under dry conditions. One example is sorghum: Also known as milo, durra, or broomcorn, sorghum is a grass species that can grow up to five meters in height and is extremely resistant to aridity and hot conditions. The grass, which originates from Africa, can thrive under conditions and locations where other cereal plants cannot survive due to lack of water. In arid-warm and moderate regions of the Americas, Asia and Europe it is mainly utilized for food and fodder and is also gaining in significance as a basis for bio-fuel. The plant also provides fibers as well as combustible material for heating and cooking.

As part of an international consortium of scientists, researchers at Helmholtz Zentrum München are analyzing the genes of sorghum, the first plant of African origin whose genome has been sequenced.

Dr. Klaus Mayer of the Institute of Bioinformatics and Systems Biology of the Helmholtz Zentrum München described the scientists’ research goal:

”We want to elucidate the functional and structural genomics of sorghum.“

He went on to explain:
”That is the prerequisite for making this important grain even more productive through targeted breeding strategies. As German Research Center for Environmental Health, sustaining the food supply is one of our most important research topics. That is why we are trying to learn something about the molecular basis of the plant’s pronounced drought tolerance in order to apply this knowledge to other crop plants in our latitude zone as well. “

The first results of the study have been published in the current issue of Nature.

What makes sorghum interesting as a model system is that it is more closely related to the predominant grains of tropical origin, for example maize, than it is to rice. Moreover, sorghum, unlike many other crop plants, has not undergone genome enlargement in the past millions of years. Its rather small genome – about one-fourth as large as the human genome – is a good starting point for investigating the more complex genomes of important crop plants such as maize or sugarcane, especially since sorghum - like these two plants –is a ”C4 Plant".

Due to biochemical and morphological specialization, such plants use a special kind of photosynthesis (in which first a molecule with four carbon atoms is formed, thus the name). They can assimilate carbon at higher temperatures and more efficiently than ”C3 plants“ and are especially suitable for the production of biomass for energy. Sorghum is the first cereal plant with C4 photosynthesis whose genome has been completely sequenced. The analysis of its functional genomics provides new insights into the molecular differences between C3 and C4 plants.Furthermore, the comparison with the C3 plant rice - likewise completely sequenced – gives us information about how these cereals became more divergent in the course of evolution.The data of the Munich scientists also allow a comparative analysis of sorghum, rice and maize. This analysis yields information about the evolution of the genome size, distribution and amplification of genes or recombination processes.

Last but not least, the researchers have validated a method in their study - whole genome shotgun sequencing – which is an especially fast and inexpensive method of sequencing complete chromosomes and genomes. In this method, the DNA is copied multiple times and then shredded into many small fragments by squeezing the DNA through a pressurized syringe. Finally the fragments are sequenced from both ends ans sub sequentially the millions of small DNA fragments are assembled by elaborate computational methods into complete chromosomes.

Biofuels: Think Outisde The Barrel


Rising oil prices have led to an increased interest in biofuels as an alternative energy source.

Bioenergy
is produced from organic matter or biomass. Biomass produced in a sustainable manner becomes a renewable energy source. It stores chemical energy that can be used to produce power and heat. Biofuels are energy carriers derived from biomass. Some historic and conventional sources of bioenergy are fuel wood, charcoal and animal dung. There are two generations of biofuels; First generation biofuels and second generation biofuels.


First generation Biofuels:

First generation bio-fuels are derived from food crops. Most important among them are;

  • Ethanol
  • Biodiesel
Ethanol can be made form sugars (e.g. sugar beets, sugarcane); grains (maize and wheat), cellulose and waste products. Sugar from Brazil and Maize from USA comprise around 80% of global ethanol production. In energy terms, ethanol accounts for almost 90% of current total biofuel use. Biodiesel is made from vegetable oil or animal fats biodiesel mostly produced and used in Europe.


Second Generation Biofuels:

Second generation biofuels are derived from the residual non-food parts of crops, such as stem, leaves and husks that are left behind once the food crop has been extracted. Second generation biofuels also include other crops that are not used for food purpose such as Switch Grass. Second generation biofuels are not likely to increase food prices. Also they are more helpful in mitigating climate changes as compared to first generation biofuels.

Rising oil prices have led to increased interest in biofuels as an alternative energy source. By April 2008 crude petroleum prices were as much as $120. The following section will describe the potential benefits of Bioenergy.

The potential benefits of bioenergy development are as under:

  • Its ability to compete with petroleum prices
  • Its ability to mitigate climate changes
  • Its capacity to reduce GHG emission
  • Its ability to enhance farmer’s income
  • Diversification of agriculture outputs
  • Domestic energy supply
  • Job creation in rural areas
  • Development of infrastructures
It is projected that biofuels will meet 3.2% of world road-transport fuel demand by 2030. (Source: World Energy Outlook) The primary motives behind promoting the development of bioenergy is climate change mitigation, energy security and agricultural and rural development. But can biofuels reality deliver? There is also a negative facet of the story. There are several challenges posed by the increased usage of bioenergy.


  • Growth of bioenergy sector may lead to:
  • Food shortages,
  • Water shortages,
  • Malnutrition
  • Rise in the food prices,
  • Soil erosion,
  • Deforestation
  • and many other challenges that are still unknown to us.

In the following section of this article, we will try to have a clear view of challenges of bioenergy.


CHALLENGES OF BIOENERGY


(A)-Diversion of Food to Fuel and Rise in Food Prices:

Availability of food can be threatened to the extent that land, land, water and other productive resources are diverted from food production to biofuel production. According to a study, in 2008, 24% of US maize crop projected to go into ethanol production. In 2007, 54% of Brazil’s sugar-cane crop production was used to produce ethanol. In the European Union, about 47% of vegetable oil production was used in the production of biodiesel causing higher imports of vegetable oil to meet domestic consumption needs.

There is another risk that food and feed production will be consigned to less productive land, which may result in lower yields, while the most fertile lands with be cultivated for high-value fuel crops. Agrofuel plantations in Brazil and Southeast Asia are being created on the territories of indigenous people and local subsistence farmers, who are being forced to give up their land, way of life, and food self sufficiency to grow fuel crops for export. The increased biofuel demand have accounted for a substantial increase in food prices.

A rise in food prices will tend to result in reduced access to food of higher value. As prices continue to rise, poor people (who represent a majority of net buyers of food) will experience a worsening of dietary quality and micronutrient intake and extremely poor people will experience an additional decrease in food energy consumption.

Decreased food consumption in terms of calories, proteins, fats and micronutrients can lead to:

  • Weight loss
  • Impaired development
  • Impaired mental and physical growth in children
  • Reduction in physical ability to do work for adults
A study suggests that in East Asian setting a 50% increase in price of food (holding income constant) will lead to decline of iron intake by 30%. As a result, prevalence of micronutrient deficiency among women and children will increase by 25%.


Recently “The Economist” Magazine editorialized:

“Roughly a billion people live on $1 a day. If, on a conservative estimate, the cost of their food rises 20% (and in some places it has risen a lot more), 100 Million people could be forced back to absolute poverty.”

(B)-Increased GHG Emissions Connected with Biofuel Production:

Biofuel production can disturb GHG emissions balance through increased GHG emissions that may result from burning forests to clear land for crop cultivation, which causes less absorption of carbon dioxide and hence GHG concentration increases in the biosphere, which may result in more global warming.

Key sources of emissions from bioenergy development are:

  • Land Conversion
  • Mechanization
  • Fertilizer use at feedstock production stage
  • Use of non-renewable energy in processing and transport

(C)-Expanded Bioenergy Sector Poses a Challenge of Water Scarcity:


  • Development of bioenergy sector may lead to water shortages.
  • Use of sugarcane as a feedstock is particularly water intensive.
  • Increased cultivation of biofuel crops could result into loss of availability of drinking water in many regions of Earth.
  • Water scarcity in countries of South Asia and Sub-Saharan Africa is a cause of concern for agricultural productivity, health and sanitation.



More Challenges:

(D)-Water Pollution and Soil Erosion:

Biofuel Crops such as soybean and corn contribute to soil erosion and water pollution and require large amount of fertilizer, pesticides and fuel to grow, harvest and dry. Also poorly managed input use in bioenergy crop cultivation could pollute drinking water, adversely affecting human and animal health.


(E)-Threat to Biodiversity:

Planning for expanding bioenergy sector involve the creation of large scale mono-cropping plantation, which threaten some of the most biodiverse ecosystems on the Earth. The threat to wild biodiversity from bioenergy growth is associated with land-use change. When areas such as natural forests are converted for feedstock production, the loss of biodiversity may be significant.


FAO High Level Conference:

At June 3-5, 2008 Food and Agricultural Organization (FAO) High Level Conference on “World Food Security: The Challenges of Climate Change and Bioenergy took place. The conversion of foodstuffs like maize, sugar and palm oil into biofuels was one of the most controversial issues in that High Level Conference. During the summit the biofuel giants, USA and Brazil remarked against countries that fear the harmful effects of bioenergy and under their pressure, the final declaration avoided negative language on this issue. US and Brazil states that bioenergy present “Challenges and Opportunities” and call for an “International Dialogue” on the matter.

On the other hand, 3 member states of FAO, Argentine, Cuba and Venezuela did not adopt the declaration on the grounds that rich and powerful states want to block true solutions to world hunger and condemned monopolies on agriculture.

In the conference, a lack of focus on the development of second generation biofuels seemed a surprising aspect, because first-generation biofuels compete with food crops. Also first-generation biofuels contribute to climate change which is a serious challenge to food security.


Managing Bioenergy - The Global Perspective:

The different viewpoints on managing bioenergy sector globally can be summarized under three main options:

  1. Business as usual
  2. Moratorium
  3. Intergovernmental Consensus Building
The “Business as usual” option focuses continuing along the path taken so far. The “Moratorium” option denotes a temporary prohibition of production. Intergovernmental Consensus building on sustainable bioenergy sector assumes that policy making on sustainable biofuels is necessary but may not be sufficient for sustainable bioenergy development.

Bioenergy
and Climate Change- The Challenge of Sustainable Development:
To develop the full potential of bioenergy so as to mitigate abrupt global climate changes, growth has to be managed in a sustainable way to meet requirements related to socio-economic and environmental dimensions of sustainability. The emerging bioenergy market should build upon

following lessons to meet the above described challenges:
Proper management and appropriate policies can make bioenergy development more pro-poor and environmentally sustainable. Poor farmers might be able to grow energy crops on degraded lands, not suitable for food production. But appropriate fertilizer management, soil type and climatic conditions are to be considered in order to prevent soil erosion, environmental problems, GHG emissions and harmful climate changes.

Proper research and institutional arrangements can prevent a negative impact on food availability, climate and poverty. Bioenergy sector is labor intensive. Optimized production will open new vistas for employment (without disturbing ecosystems). A study shows that in 1997, in Brazil, the ethanol sector employed about 1 Million people.


Conclusion:

Taking all these factors into account, it is clear that International Community is facing difficulties in coping with the challenges posed by Climate change and Bioenergy. On one hand, climate changes and current bioenergy policies and practices run the risk of undermining food security and degrading ecosystems through deforestation and agrochemical pollution. On the other hand well-managed “second generation” biofuels can contribute to a more sustainable energy future and climate change adaptation. Thus it can be concluded that the challenges posed by Climate change and Bioenergy are grave, without any doubt, but research is underway to manage biofuels in a global perspective and it could help us in overcoming many problems including Climate Change Mitigation, if managed successfully.