To address climate change, nothing substitutes for reducing carbon dioxide emissions

 

The politically expedient way to mitigate climate change is essentially no way at all, according to a comprehensive new study by University of Chicago climatologist Raymond Pierrehumbert.

Among the climate pollutants humans put into the atmosphere in significant quantities, the effects of carbon dioxide (CO₂) are the longest-lived, with effects on climate that extend thousands of years after emissions cease. But finding the political consensus to act on reducing CO₂ emissions has been nearly impossible. So there has been a movement to make up for that inaction by reducing emissions of other, shorter-lived gasses, such as methane, hydrofluorocarbons, and nitrous oxide, and particulates such as soot and black carbon, all of which contribute to warming as well.

Pierrehumbert 's study shows that effort to be, as he puts it, a delusion. "Until we do something about CO₂, nothing we do about methane or these other things is going to matter much for climate," he said.

Pierrehumbert is the Louis Block Professor in Geophysical Sciences at UChicago, and holder of the King Carl XVI Gustaf Chair in Environmental Sciences at Stockholm University for 2014-2015. His study, published in Annual Review of Earth and Planetary Sciences, brings together findings from the scientific literature with new research and analysis. Its conclusions are clear.

"Ray convincingly shows the benefit and importance of doing everything we can to lower CO₂ emissions, and as soon as possible," said Katherine H. Freeman, professor of geosciences at Pennsylvania State University. "We should lower short-lived pollutants like methane too. But, as he makes clear, we should not let them distract us from the urgent need to stop burning fossil fuels."

The basic physics of climate pollutants has been well known for a long time. The warming effect of methane and other short-lived climate pollutants disappears quite quickly after the pollutants are removed from the atmosphere. When you remove them, you get a one-time-only, lump-sum benefit. CO₂, on the other hand, lingers in the atmosphere. And if you are still emitting CO₂ while you are reducing methane and its fellows, that additional CO₂ continues to affect the climate for thousands of years.

Perhaps as a result of wishful thinking, the policy implications of those facts had become confused, said Pierrehumbert. Part of the problem is that the statistical tool used to compare the climate effect of gasses is badly flawed. The measure, called Global Warming Potential (GWP), predicts the effect on climate by comparing the emission rate of carbon dioxide with the emission rate of methane. But a one-ton-per-year reduction in the amount of methane emitted translates into a single lowering of the global thermostat, while a one-ton-per-year reduction in CO₂ yields a climate benefit that increases over time. That's because each extra ton of CO₂ that would have been emitted would have irreversibly ratcheted up the global thermostat by an additional increment.

Despite its well-known defects, GWP has been used since 1990 and was incorporated into the Kyoto Protocols in the climate-trading schemes implemented by Europe. Pierrehumbert proposes a different metric, which looks at the climate effect of reducing CO₂ emission by a fixed number of tons and then finds the rate by which you have to reduce methane emissions to get the same effect.

Pierrehumbert's study doesn't propose a single "right" policy on climate change, said Richard Alley, Evan Pugh Professor of Geosciences at Penn State. "But it is a very useful analysis that will be viewed carefully by people who are interested in making good policies, and the main conclusions will help inform those policies."

Pierrehumbert himself hopes that his work will help lead policymakers to abandon Kyoto-style multi-gas trading schemes, which treat the gasses equivalently, and put the emphasis on CO₂ for the next 50 years or so. "I see puncturing the excessive enthusiasm about short-lived climate pollution control as a step in the right direction," he said, "because it takes away one of the grounds for procrastination on CO₂. If you're serious about protecting climate, it's the CO₂ you've got to deal with first."

Unprecedented 3-D view of important brain receptor

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X-ray crystal structure of the NMDA receptor showing its mushroom- like shape, with receptor subunits in different colors.

Researchers with Oregon Health & Science University's Vollum Institute have given science a new and unprecedented 3-D view of one of the most important receptors in the brain -- a receptor that allows us to learn and remember, and whose dysfunction is involved in a wide range of neurological diseases and conditions, including Alzheimer's, Parkinson's, schizophrenia and depression.

The unprecedented view provided by the OHSU research, published online June 22 in the journal Nature, gives scientists new insight into how the receptor -- called the NMDA receptor -- is structured. And importantly, the new detailed view gives vital clues to developing drugs to combat the neurological diseases and conditions.

"This is the most exciting moment of my career," said Eric Gouaux, a senior scientist at the Vollum Institute and a Howard Hughes Medical Institute investigator. "The NMDA receptor is one of the most essential, and still sometimes mysterious, receptors in our brain. Now, with this work, we can see it in fascinating detail."

Receptors facilitate chemical and electrical signals between neurons in the brain, allowing those neurons to communicate with each other. The NMDA (N-methyl-D-aspartate) receptor is one of the most important brain receptors, as it facilitates neuron communication that is the foundation of memory, learning and thought. Malfunction of the NMDA receptor occurs when it is increasingly or decreasingly active and is associated with a wide range of neurological disorders and diseases. Alzheimer's disease, Parkinson's disease, depression, schizophrenia and epilepsy are, in many instances, linked to problems with NMDA activity.

Scientists across the world study the NMDA receptor; some of the most notable discoveries about the receptor during the past three decades have been made by OHSU Vollum scientists.

The NMDA receptor makeup includes receptor "subunits" -- all of which have distinct properties and act in distinct ways in the brain, sometimes causing neurological problems. Prior to Gouaux's study, scientists had only a limited view of how those subtypes were arranged in the NMDA receptor complex and how they interacted to carry out specific functions within the brain and central nervous system.

Gouaux's team of scientists -- Chia-Hsueh Lee, Wei Lu, Jennifer Michel, April Goehring, Juan Du and Xianqiang Song -- created a 3-D model of the NMDA receptor through a process called X-ray crystallography. This process throws x-ray beams at crystals of the receptor; a computer calibrates the makeup of the structure based on how those x-ray beams bounce off the crystals. The resulting 3-D model of the receptor, which looks something like a bouquet of flowers, shows where the receptor subunits are located, and gives unprecedented insight into their actions.

"This new detailed view will be invaluable as we try to develop drugs that might work on specific subunits and therefore help fight or cure some of these neurological diseases and conditions," Gouaux said. "Seeing the structure in more detail can unlock some of its secrets -- and may help a lot of people."

O que um gringo pensa do Brasil

 

Duas semanas de Brasil e meu horário ainda está desregulado. Meu estômago também está desregulado. Ontem me levaram a um bloco de maracatu num inferninho. Bebemos caipirinhas demais. Alguns amigos ainda estão por aqui no quarto, batucando e bebendo. O que não contam, antes de vir para o Brasil, é que aqui a festa não acaba nunca.

As mulheres são tudo o que se diz delas: morenas, com curvas, chapinhas e obscenamente bonitas. E não têm qualquer pudor de chegar nos homens. São o que aqui se chama de desencanadas. Têm a consciência menos pesada do que as europeias.

Dos homens, nem sei o que dizer; quase não reparei neles. Dos que me foram apresentados, percebi que a maioria é fanho, com voz de ganso - pode ser o sotaque. Muitos deles usam uma barba de Conchita Wurst. A versão feminina usa vestido florido e sapato de boneca. Uma dessas, desde a hora que acordou, não para de falar comigo.

Brasileiros têm horror ao silêncio. Tudo precisa ser comentado; do seu sapato ao seu topete, da umidade relativa do ar ao jogo do Irã, e quase não tem um lugar onde não existe alguém falando, muito menos espaço para ficar sozinho. Ainda procuro descobrir as regras de convívio. Uma que logo percebi é que em grupo todo mundo pode falar ao mesmo tempo. Aquele que for mais rápido pode cortar o assunto do outro. Quanto a isso, parece que não há nenhum problema, ninguém se irrita. Mas o assunto tampouco é retomado.

Uma diversão tipicamente brasileira é puxar papo na fila, no bar, no mictório. Em poucos minutos é possível saber da vida inteira de um desconhecido que mija do seu lado. Você entra no banheiro público e sai de lá com um amigo novo. É uma intimidade que, para quem não está acostumado, pode passar por deseducada. Disse uma tiazinha do hostel que essa invasão da intimidade explica as altas taxas de violência - o que faz algum sentido. Roubos e furtos não faltam por aqui. Não encontrei ninguém que não tenha tido o celular roubado ou furtado pelo menos uma vez nos últimos anos.

No momento só se fala de futebol, mas alguns parecem um pouco apreensivos com as eleições daqui a alguns meses. Dilma, Sarney, Luciano Huck, muitos invocam esses nomes na tevê. O que será Cátia Fonseca?

O país é uma festa sem fim, rico de diversões. Todos os lugares por onde passei, vi ruas pintadas de verde e amarelo, bandeirinhas verdes e amarelas, poodles e crianças pintados de verde e amarelo.

A cerveja é fraca, aguada. Mas o calor ajuda.

Os fracos da cabeça, além de bêbados, põem o som do carro no último volume - olha aí a invasão da privacidade de que eu estava falando. Funk carioca institucionalizou-se como música oficial. O funk domina as ruas. É um poder paralelo. Já os bêbados são os mesmos de todos os lugares.

Uma de minhas diversões preferidas é observar como brasileiros reagem quando criticamos alguma coisa que não funciona direito aqui. Eles ficam apreensivos em saber o que os estrangeiros pensam deles. Adoram se sentir o centro das atenções. A Copa, nesse sentido, cobriu o país de júbilo. Tornou real o sonho brasileiro de ser o centro das atenções. A maneira mais rápida de irritar um brasileiro, segundo uma mendiga que conheci, é falar mal do país - mas eles mesmos são ótimos nisso.

As capitais combinam a arquitetura antiga com a moderna. Mas os prédios mais antigos vão todos morrendo. No lugar há estacionamentos, prédios com varandas gourmet e templos de igrejas pentecostais. Algumas estações de metrô parecem shopping center. Prédios de luxo, como as favelas, são um show de horror à parte. Mesmo que seja um país com tanta desigualdade, pobres e ricos dividem o mau gosto igualmente.

Você ficaria horrorizada com as casas daqui, carentes de jardins, de livros, de pôsteres.

O que não quer dizer que brasileiros não sejam apreciadores de arte. Longe disso. Voltava para o hostel outro dia quando um homem me perguntou se eu gostava de teatro. Depois, em mais duas ocasiões, outros homens me perguntaram a mesma coisa. Achei curioso. Brasileiros devem gostar muito de teatro, e de maracatu e de poesia.

Estou voltando com uma mala só de bugigangas. Paçocas, pedras, Fulecos, araras de ametista, tucanos entalhados em madeira, livros de Jorge Amado, CD da Claudia Leitte - a Beyoncé deles -, biquínis, palavras terminadas em inho e saudade, bastante saudade.

(30% correto, Guy Franco) . Se você nasceu nos EUA, dê uma espiada como estão as coisas por lá, mas esqueça as fachadas.

Bem preparados emocionalmente

 

Luana Barbosa estava na garupa da motocicleta do namorado que, segundo a polícia, não parou no bloqueio;atriz levou um tiro no tórax disparado pelo cabo Marcelo Aparecido Domingos Coelho

A atriz Luana Barbosa, de 25 anos, foi morta nessa sexta-feira, 27, pelo cabo da Polícia Militar, Marcelo Aparecido Domingos Coelho, em uma blitz de trânsito em Presidente Prudente, no oeste paulista. Ela levou um tiro no tórax.

A atriz, que fez aniversário na quinta-feira, estava na garupa da motocicleta do namorado, o músico Felipe Fernandes de Barros, de 29 anos. Ele não parou no bloqueio, segundo a PM. A versão foi desmentida por amigos do músico, garantindo que Barros procurava um lugar para estacionar quando houve o disparo.

Bombeiros socorreram a jovem, que deu entrada no Hospital Regional. Ela não resistiu e morreu pouco depois. O cabo Coelho, de 43 anos, foi preso em flagrante. Ele está no Presídio Romão Gomes, em São Paulo. A arma teria disparado acidentalmente, segundo o cabo, que está há 23 anos na Polícia Militar.

Ouvido pelo Estado, um porta-voz da PM disse que um inquérito foi aberto para apurar o caso em 40 dias. "Pode ser prorrogado por mais 20 dias", afirmou. Ele não soube dizer se o cabo será expulso da corporação.

Atriz e produtora. Além de atriz, Luana Barbosa também era produtora de espetáculos teatrais. Ela era integrante da Federação Prudentina de Teatro e Artes Integrados. A jovem foi enterrada no começo da tarde deste sábado, 28, em Rancharia, onde moram seus pais.

(Arma disparada acidentalmente por um CABO há 23 anos na Policia Militar? )

Not much force: Researchers detect smallest force ever measured

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Mechanical oscillators translate an applied force into measureable mechanical motion. The Standard Quantum Limit is imposed by the Heisenberg uncertainty principle, in which the measurement itself perturbs the motion of the oscillator, a phenomenon known as “quantum back-action.”

What is believed to be the smallest force ever measured has been detected by researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley. Using a combination of lasers and a unique optical trapping system that provides a cloud of ultracold atoms, the researchers measured a force of approximately 42 yoctonewtons. A yoctonewton is one septillionth of a newton and there are approximately 3 x 10²³ yoctonewtons in one ounce of force.

"We applied an external force to the center-of-mass motion of an ultracold atom cloud in a high-finesse optical cavity and measured the resulting motion optically," says Dan Stamper-Kurn, a physicist who holds joint appointments with Berkeley Lab's Materials Sciences Division and the UC Berkeley Physics Department. "When the driving force was resonant with the cloud's oscillation frequency, we achieved a sensitivity that is consistent with theoretical predictions and only a factor of four above the Standard Quantum Limit, the most sensitive measurement that can be made."

Stamper-Kurn is the corresponding author of a paper in Science that describes these results. The paper is titled "Optically measuring force near the standard quantum limit." Co-authors are Sydney Schreppler, Nicolas Spethmann, Nathan Brahms, Thierry Botter and Maryrose Barrios.

If you want to confirm the existence of gravitational waves, space-time ripples predicted by Albert Einstein in his theory of general relativity, or want to determine to what extent the law of gravity on the macroscopic scale, as described by Sir Isaac Newton, continues to apply at the microscopic scale, you need to detect and measure forces and motions that are almost incomprehensively tiny. For example, at the Laser Interferometer Gravitational-Wave Observatory (LIGO), scientists are attempting to record motions as small as one thousandth the diameter of a proton.

At the heart of all ultrasensitive detectors of force are mechanical oscillators, systems for translating an applied force into measureable mechanical motion. As measurements of force and motion reach quantum levels in sensitivity, however, they bump up against a barrier imposed by the Heisenberg uncertainty principle, in which the measurement itself perturbs the motion of the oscillator, a phenomenon known as "quantum back-action." This barrier is called the Standard Quantum Limit (SQL). Over the past couple of decades, a wide array of strategies have been deployed to minimize quantum back-action and get ever closer to the SQL, but the best of these techniques fell short by six to eight orders of magnitude.

"We measured force with a sensitivity that is the closest ever to the SQL," says Sydney Schreppler, a member of the Stamper-Kurn research group and lead author of the Science paper. "We were able to achieve this sensitivity because our mechanical oscillator is composed of only 1,200 atoms."

In the experimental set-up used by Schreppler, Stamper-Kurn and their colleagues, the mechanical oscillator element is a gas of rubidium atoms optically trapped and chilled to nearly absolute zero. The optical trap consists of two standing-wave light fields with wavelengths of 860 and 840 nanometers that produce equal and opposite axial forces on the atoms. Center-of-mass motion is induced in the gas by modulating the amplitude of the 840 nanometer light field. The response is measured using a probe beam with a wavelength of 780 nanometers.

"When we apply an external force to our oscillator it is like hitting a pendulum with a bat then measuring the reaction," says Schreppler. "A key to our sensitivity and approaching the SQL is our ability to decouple the rubidium atoms from their environment and maintain their cold temperature. The laser light we use to trap our atoms isolates them from external environmental noise but does not heat them, so they can remain cold and still enough to allow us to approach the limits of sensitivity when we apply a force."

Schreppler says it should be possible to get even closer to the SQL for force sensitivity through a combination of colder atoms and improved optical detection efficiency. She also says there are back-action evading techniques that can be taken by performing non-standard measurements. For now, the experimental approach demonstrated in this study provides a means by which scientists trying to detect gravitational waves can compare the limits of their detection abilities to the predicted amplitude and frequency of gravitational waves. For those seeking to determine whether Newtonian gravity applies to the quantum world, they now have a way to test their theories. The enhanced force-sensitivity in this experiment could also point the way to improved atomic force microscopy.

"A scientific paper in 1980 predicted that the SQL might be reached within five years," Schreppler says. "It took about 30 years longer than predicted, but we now have an experimental set-up capable both of reaching very close to the SQL and of showing the onset of different kinds of obscuring noise away from that SQL."

This research was supported by the Air Force Office of Scientific Research and the National Science Foundation

Magnesium Supplement (Oral Route, Parenteral Route)

 

 

Descriptions

Magnesium is used as a dietary supplement for individuals who are deficient in magnesium. Although a balanced diet usually supplies all the magnesium a person needs, magnesium supplements may be needed by patients who have lost magnesium because of illness or treatment with certain medicines.

Lack of magnesium may lead to irritability, muscle weakness, and irregular heartbeat.

Injectable magnesium is given only by or under the supervision of a health care professional. Some oral magnesium preparations are available only with a prescription. Others are available without a prescription.

Importance of Diet

For good health, it is important that you eat a balanced and varied diet. Follow carefully any diet program your health care professional may recommend. For your specific dietary vitamin and/or mineral needs, ask your health care professional for a list of appropriate foods. If you think that you are not getting enough vitamins and/or minerals in your diet, you may choose to take a dietary supplement.

The best dietary sources of magnesium include green leafy vegetables, nuts, peas, beans, and cereal grains in which the germ or outer layers have not been removed. Hard water has been found to contain more magnesium than soft water. A diet high in fat may cause less magnesium to be absorbed. Cooking may decrease the magnesium content of food.

Recommended Nutrient Intakes (RNIs) are used to determine the amounts of vitamins, minerals, and protein needed to provide adequate nutrition and lessen the risk of chronic disease.

 

 

• Before Using

Abdominal pain Definition

 

Everyone experiences abdominal pain from time to time. Other terms used to describe abdominal pain are stomachache, tummy ache, gut ache and bellyache. Abdominal pain can be mild or severe. It may be continuous or come and go. Abdominal pain can be short-lived (acute) or occur over weeks and months (chronic).

Call your doctor right away if you have abdominal pain so severe that you can't move without causing more pain, or you can't sit still or find a comfortable position. Also, seek immediate medical help if pain is accompanied by other worrisome signs and symptoms, such as fever, bloody diarrhea or severe tenderness in your abdomen.

• Causes

Finasteride

 

Descriptions

 

Finasteride is used to treat men with benign prostatic hyperplasia (BPH) and male pattern hair loss, also called androgenetic alopecia. BPH is caused by an enlarged prostate. Men with BPH usually have difficulty urinating, a decreased flow of urination, hesitation at the beginning of urination, and a need to get up at night to urinate. Finasteride will make these symptoms less severe and reduce the chance that prostate surgery will be needed. It may be used alone or in combination with other medicines such as an alpha-blocker (doxazosin, Cardura®) to treat BPH. For men with hair loss, finasteride will increase the number of scalp hairs but will not increase the amount of body hair.

Finasteride blocks the action of an enzyme called 5-alpha-reductase. This enzyme changes testosterone to another hormone that causes the prostate to grow or hair loss in males. It will increase testosterone levels in the body, which decreases prostate size and increases hair growth on the scalp. The effect of finasteride on the prostate and scalp will only last as long as the medicine is taken. When it is stopped, the prostate begins to grow again and the hair will be lost.

This medicine is available only with your doctor's prescription.

This product is available in the following dosage forms:

• Tablet

• Before Using

Lycopene

 

Background

Lycopene is a bright red pigment that is naturally found in the human liver, serum (blood), adrenal glands, lungs, prostate, colon, and skin at higher levels than other similar pigments. In animal studies, lycopene has been found to have antioxidant effects and may also block cancer cell growth. However, there is still controversy over whether it has these effects in humans.

Many studies suggest that eating lycopene-rich foods or having high lycopene levels in the body may be linked to reduced risk of cancer, heart disease, and age-related eye disorders. However, measures of lycopene intake have been based on eating tomatoes, not on the use of lycopene supplements. Since tomatoes also contain other nutrients, such as vitamin C and potassium, the potential benefits of lycopene alone are still unclear.

Lycopene deficiency is not considered a medical condition. There is a lack of evidence on whether increasing low lycopene levels may benefit health.

• Related terms

New superconductor world record set

 

The Cambridge researchers managed to 'trap' a magnetic field with a strength of 17.6 Tesla -- roughly 100 times stronger than the field generated by a typical fridge magnet -- in a high temperature gadolinium barium copper oxide (GdBaCuO) superconductor, beating the previous record by 0.4 Tesla. The results are published today in the journal Superconductor Science and Technology.

The research demonstrates the potential of high-temperature superconductors for applications in a range of fields, including flywheels for energy storage, 'magnetic separators', which can be used in mineral refinement and pollution control, and in high-speed levitating monorail trains.

Superconductors are materials that carry electrical current with little or no resistance when cooled below a certain temperature. While conventional superconductors need to be cooled close to absolute zero (zero degrees on the Kelvin scale (or -273 °C) before they superconduct, high temperature superconductors do so above the boiling point of liquid nitrogen (-196 °C) which makes them relatively easy to cool and cheaper to operate.

Superconductors are currently used in scientific and medical applications, such as MRI scanners, and in the future could be used to protect the national grid and increase energy efficiency, due to the amount of electrical current they can carry without losing energy.

The current carried by a superconductor also generates a magnetic field, and the more field strength that can be contained within the superconductor, the more current it can carry. State of the art, practical superconductors can carry currents that are typically 100 times greater than copper, which gives them considerable performance advantages over conventional conductors and permanent magnets.

The new record was achieved using 25 mm diameter samples of GdBCO high temperature superconductor fabricated in the form of a large, single grain using an established melt processing method and reinforced using a relatively simple technique. The previous record of 17.2 Tesla, set in 2003 by a team led by Professor Masato Murakami from the Shibaura Institute of Technology in Japan, used a highly specialised type of superconductor of a similar, but subtly different, composition and structure.

"The fact that this record has stood for so long shows just how demanding this field really is," said Professor David Cardwell of Cambridge's Department of Engineering, who led the research, in collaboration with Boeing and the National High Field Magnet Laboratory at the Florida State University. "There are real potential gains to be had with even small increases in field."

To contain such a large field, the team used materials known as cuprates: thin sheets of copper and oxygen separated by more complex types of atoms. The cuprates were the earliest high temperature superconductors to be discovered, and have the potential to be used widely in scientific and medical applications.

While they are high quality superconductors with outstanding potential for practical applications, the cuprates can be as brittle as dried pasta when fabricated in the form of sintered ceramics, so trying to contain a strong magnetic field within bulk forms of the cuprates tends to cause them to explode.

In order to hold in, or trap, the magnetic field, the researchers had to modify both the microstructure of GdBCO to increase its current carrying and thermal performance, and reinforce it with a stainless steel ring, which was used to 'shrink-wrap' the single grain samples. "This was an important step in achieving this result," said Dr John Durrell who led the experiment in Florida.

The lines of magnetic flux in a superconductor repel each other strongly, making containing such a large field difficult. But, by engineering the bulk microstructure, the field is retained in the sample by so-called 'flux pinning centres' distributed throughout the material. "The development of effective pinning sites in GdBCO has been key to this success," said Dr Yun-Hua Shi, who has been responsible for developing the melt process fabrication technique at Cambridge for the past 20 years.

The result was the biggest ever trapped field achieved in a bulk, standalone material at any temperature.

"This work could herald the arrival of superconductors in real-world applications," said Professor Cardwell. "In order to see bulk superconductors applied for everyday use, we need large grains of superconducting material with the required properties that can be manufactured by relatively standard processes."

A number of niche applications are currently being developed by the Cambridge team and its collaborators, and it is anticipated that widespread commercial applications for superconductors could be seen within the next five years.

"This record could not have been achieved without the support of our academic and industrial colleagues and partners," said Professor Cardwell, who is the next Head of the Department of Engineering. "It was a real team effort, and one which we hope will bring these materials a significant step closer to practical applications."

"Boeing continues to see practical applications for this superconducting material research and we are excited about the possibilities being enabled by the recent advances achieved by the Cambridge team," said Patrick Stokes, who leads the Boeing-funded research portfolio with Cambridge University.