How did the equatorial ridge on Saturn's moon Iapetus form?

Evaluating a 1981 temperature projection

Sometimes it helps to take a step back from the everyday pressures of research (falling ill helps).

Guest commentary from Geert Jan van Oldenborgh and Rein Haarsma, KNMI

Sometimes it helps to take a step back from the everyday pressures of research (falling ill helps). It was in this way we stumbled across Hansen et al (1981) (pdf). In 1981 the first author of this post was in his first year at university and the other just entered the KNMI after finishing his masters. Global warming was not yet an issue at the KNMI where the focus was much more on climate variability, which explains why the article of Hansen et al. was unnoticed at that time by the second author. It turns out to be a very interesting read.

They got 10 pages in Science, which is a lot, but in it they cover radiation balance, 1D and 3D modelling, climate sensitivity, the main feedbacks (water vapour, lapse rate, clouds, ice- and vegetation albedo); solar and volcanic forcing; the uncertainties of aerosol forcings; and ocean heat uptake. Obviously climate science was a mature field even then: the concepts and conclusions have not changed all that much. Hansen et al clearly indicate what was well known (all of which still stands today) and what was uncertain.

Fig. 6. Projections of global temperature. The diffusion coefficient beneath the ocean mixed layer is 1.2 cm² sec^-1, as required for best fit of the model and observations for the period 1880 to 1978. Estimated global mean warming in earlier warm periods is indicated on the right.

Next they attribute global mean temperature trend 1880-1980 to CO2, volcanic and solar forcing. Most interestingly, Fig.6 (below) gives a projection for the global mean temperature up to 2100. At a time when the northern hemisphere was cooling and the global mean temperature still below the values of the early 1940s, they confidently predicted a rise in temperature due to increasing CO2 emissions. They assume that no action will be taken before the global warming signal will be significant in the late 1990s, so the different energy-use scenarios only start diverging after that.

The first 31 years of this projection are thus relatively well-defined and can now be compared to the observations. We used the GISS Land-Ocean Index that uses SST over the oceans (the original one interpolated from island stations) and overlaid the graph from the KNMI Climate Explorer on the lower left-hand corner of their Fig.6.

Given the many uncertainties at the time, notably the role of aerosols, the agreement is very good indeed. They only underestimated the observed trend by about 30%, similar or better in magnitude than the CMIP5 models over the same period (although these tend to overestimate the trend, still mainly due to problems related to aerosols).

To conclude, a projection from 1981 for rising temperatures in a major science journal, at a time that the temperature rise was not yet obvious in the observations, has been found to agree well with the observations since then, underestimating the observed trend by about 30%, and easily beating naive predictions of no-change or a linear continuation of trends. It is also a nice example of a statement based on theory that could be falsified and up to now has withstood the test. The “global warming hypothesis” has been developed according to the principles of sound science.

References J. Hansen, D. Johnson, A. Lacis, S. Lebedeff, P. Lee, D. Rind, and G. Russell, "Climate Impact of Increasing Atmospheric Carbon Dioxide", Science, vol. 213, 1981, pp. 957-966. DOI.

http://news.discovery.com/human/jesus-happy-120406.html

Was Jesus Happy?

How you answer that question says a lot about the culture that influenced you most.

By Jennifer Viegas

Although Biblical descriptions of Jesus are essentially the same worldwide, responses to the question "Was Jesus happy?" widely differ. Researchers have found that the answers are predicted by the respondent's country and culture. The image of Jesus might be culturally constructed to fit an existing ideal, or it could be a reflection of the individual's self-image. Americans tend to think Jesus was happy, extroverted, agreeable, kind and caring. Koreans, on the other hand, associate Jesus more with suffering, sacrifice, and pity, according to a recent analysis in Personality and Social Psychology Connections and a paper published in the Journal of Research in Personality.

Responses to the simple question about Jesus and happiness, whose Biblical depiction is essentially the same worldwide, turn out to involve complex factors, such as shared life histories among groups of people, culture and possibly even genetics. All of these can affect how an individual defines what the optimal personality or self should look like.

“Americans meet far more strangers than others and need to be more extroverted than the Japanese, Koreans and others who tend to interact with a small number of people repeatedly, so extroversion is a highly valued asset in the U.S.,” Shigehiro Oishi, lead author of the study, told Discovery News. “In the end, happiness, extroversion, and kindness are all highly valued qualities among Americans, and they might just see Jesus to have these highly desirable characteristics.”

For the study, Oishi, an associate professor in the Department of Psychology at the University of Virginia, and colleagues Kyoung Ok Seol, Minkyung Koo, and Felicity Miao asked Korean and American university students to engage in a free association task with Jesus as a target. The researchers said they chose Americans and Koreans because many people identifying as Christian exist in both populations. Americans associated Jesus primarily with positive connotations (“awesome” was a common response) and rarely with negative connotations, such as “pain,” which was more frequently mentioned by the Korean study participants.

In a second part of the study, the researchers asked the test subjects to rate Jesus and themselves using personality and well-being scales. Americans again tended to emphasize happiness over sorrow.

Oishi said that “Buddhism and other religions had been firmly in place in Korea before the introduction of Christianity, and life is suffering in Buddhism.”

“Buddhism came out of a really tough societal condition,” he continued. “Most people were suffering. The main goal of Buddhism was to reduce pain and suffering. Because Christianity was introduced long after Buddhism in Korea, probably the part of Christianity that fits well with Buddhism was emphasized in Korea.”

Other cultural differences may further explain the American and Korean responses. Oishi said such differences pose “an egg and chicken problem” involving genetics and shared life experiences, since one can affect the other. It is also unclear if the image of Jesus might be culturally constructed to fit an existing ideal, or if it could reflect an individual's self-image.

Casey Eggleston, a researcher at the University of Virginia, told Discovery News that language differences also come into play, with the meaning of happiness differing across cultures over time.

“The historical definition included concepts of luck and good fortune, but that meaning has fallen out of use in the U.S., where many believe they can pursue and obtain happiness by their own effort, while it remains a major part of the concept in most other cultures,” she explained. “Similarly, the emotional connotation of the word happy varies substantially. While the American concept typically includes upbeat positive emotions like excitement, the concept in East Asia tends to focus more on calm positive emotions like peace and contentment.”

The researchers chose to focus on two particular countries, but they expect respondents in other nations with a large Christian base would also provide different, culture-predicted responses to the question, “Was Jesus happy?”

As for their own answers, Eggleston said, “There are two primary approaches to happiness: hedonia and eudaimonia. Hedonia is a state of pleasure and physical enjoyment. In the sense of feeling good, I don’t think Jesus was happy most of the time, although he undoubtedly had pleasant moments during his ministry.”

“Eudaimonia, on the other hand, is happiness achieved through virtuous living—pursuing a meaningful, viable life and doing so with integrity,” she added. “If we use this Aristotelian understanding of happiness, I think Jesus must have been exceedingly happy.”

As for Oishi’s answer to whether or not Jesus was happy, he said, “I don’t know for sure, but I don’t think so. He had a tough life.”

http://www.eurekalert.org/pub_releases/2012-04/tcd-trr040612.php

Trinity researchers report major eye disease breakthrough

Controlling an inflammatory component IL-18 in age-related macular degeneration could prevent the development of the disease

Scientists at Trinity College Dublin have discovered that a part of the immune system called the inflammasome is involved in regulating the development of one of the most common forms of blindness, called Age-Related Macular Degeneration (AMD). They have discovered that controlling an inflammatory component IL-18, in cases of Age-Related Macular Degeneration (AMD) could prevent the development of the disease.

The disease AMD involves loss of central vision, people with advanced disease being unable to read, watch TV, enjoy the cinema, drive, or use a computer − in short, everyday living becomes very difficult. The research, which is published this week in the international medical journal, Nature Medicine, is supported by Science Foundation Ireland, the American Health Assistance Foundation (AHAF), the Health Research Board (HRB) and Fighting Blindness Ireland.

The key diagnostic feature of AMD is the presence of "drusen", which are recognised during an eye exam as yellowish/white deposits in the central region of the retina called the macula. Dry AMD is characterised by the presence of excessive amounts of drusen and there are currently no forms of therapy other than recommended lifestyle changes such as giving up smoking, which is a recognised risk factor. However, a significant number of cases of the "dry" form of AMD can progress to the "wet" form, where blood vessels underneath the retina begin to grow, leading to central blindness. If you hold two coins immediately in front of your eyes, you will see a single large black circle blocking out your central vision. This is a very realistic simulation of what it is like to live with advanced disease.

The leading co-authors of the Nature Medicine paper, Trinity College scientists, Dr Sarah Doyle and Dr Matthew Campbell have together discovered that drusen accumulating in the macula can lead to the production of two inflammatory components termed IL-1beta and IL-18. These findings were based on studies involving drusen isolated from donor AMD eyes in tandem with pre-clinical studies on models of the disease.

"Traditionally, inflammation in the retina or indeed the eye in general is not beneficial and is a pathological hallmark of many eye diseases, including AMD. However we have identified, that one inflammatory component termed IL-18 acts as a so-called anti-angiogenic factor, preventing the progression of wet AMD" says Dr. Campbell. "The progression from "dry" to "wet" AMD appears to be mediated by the inflammatory component IL-18, our results directly suggest that controlling or indeed augmenting the levels of IL-18 in the retinas of patients with dry AMD could prevent the development of the wet form of disease, which leads us to an exciting new prospect for a novel therapy for AMD" says Dr Doyle.

The research was undertaken at Trinity College's Ocular Genetics Unit, Director, Professor Pete Humphries and at the laboratories of Professor Luke O'Neill at the Trinity Biomedical Sciences Institute, in collaboration with Professor Joe Holyfield at the Cole Eye Institute at Cleveland, Ohio.

Full title of the paper: 'NLRP3 has a protective role in age-related macular degeneration through the induction of IL-18 by drusen components'

http://www.eurekalert.org/pub_releases/2012-04/tmsh-nb040512.php

New 'genetic bar code' technique establishes ability to derive DNA information from RNA

Discovery may create dialogue about DNA and RNA data bank privacy issues

Researchers from Mount Sinai School of Medicine have developed a method to derive enough DNA information from non-DNA sources—such as RNA—to clearly identify individuals whose biological data are stored in massive research repositories. The approach may raise questions regarding the ability to protect individual identity when high-dimensional data are collected for research purposes. A paper introducing the technique appears in the April 8 online edition of Nature Genetics.

DNA contains the genetic instructions used in the development and functioning of every living cell. RNA acts as a messenger that relays genetic information in the cell so that the great majority of processes needed for tissue to function properly can be carried out.

To date, access to data bases with DNA information has been restricted and protected as it has long been considered the sole genetic fingerprint for every individual. However, vast amounts of RNA data have been made publicly available via a number of databases in the United States and Europe. These databases contain thousands of genomic studies from around the world.

In this study, lead authors Eric E. Schadt, PhD, and Ke Hao, PhD, developed a technique whereby a person's DNA could be inferred from RNA data using gene-expression levels monitored in any of a number of tissues. In contrast, most studies involving DNA and RNA begin with DNA sequences and then seek to associate expression patterns with changes in DNA between individuals in a population. This is the first time going from RNA levels to DNA sequence has been described.

"By observing RNA levels in a given tissue, we can infer a genotypic barcode that uniquely tags an individual in ways that enables matching the individual to an independently derived DNA sample," said Dr. Schadt, Director of the Institute for Genomics and Multiscale Biology, the Jean C. and James W. Crystal Professor of Genomics, and Chair of the Department of Genetics and Genomics Sciences, Mount Sinai School of Medicine. "The potential uses for this information are significant. Not only can genotypic barcodes be deduced from RNA, but RNA levels in some tissue can inform not only individual characteristics like age and sex, but on diseases such as Alzheimer's and cancer, as well as the risks of developing those diseases."

Schadt adds, "The significance of our findings goes beyond medicine. For example, barcodes derived from individuals who participated in a research study, where RNA levels were monitored and deposited into publicly available databases, could be tested against DNA samples left at a crime scene as a way of identifying persons of interest."

Deducing a person's DNA sequence from gene expression patterns could have repercussions in health care and privacy. While specific laws and government regulations have been written to protect DNA-based information from misuse, it is unclear whether such laws apply to RNA—even though this study shows that RNA is informative at a deeper level compared to DNA regarding the current state of health of an individual.

"Rather than developing ways to further protect an individual's privacy given the ability to collect mountains of information on him or her, we would be better served by a society that accepts the fact that new types of high-dimensional data reflect deeply on who we are," Dr. Schadt said. "We need to accept the reality that it is difficult—if not impossible—to shield personal information from others. It is akin to trying to protect privacy regarding appearances, for example, in a public place."

Dr. Schadt said he hopes the research will catalyze a discussion that might ultimately help resolve privacy debates, and encourage patients to provide data that will help their doctors better diagnose and treat their conditions. Increased access to, and greater quantities of, DNA and other biological information would also contribute to the greater good of medical science.

In the Nature Genetics study, Drs. Schadt and Hao, Associate Professor of Genetics at Mount Sinai School of Medicine, together with Sangsoon Woo, PhD, from the Department of Biostatistics at the University of Washington, analyzed RNA and DNA from 378 livers donated by European-Americans for transplant, as well as liver and adipose tissues from 580 people from the same population group undergoing gastric bypass surgery. The authors found that levels of RNA across many genes correlate with age, sex, body weight, and other risk factors for diseases like diabetes and heart disease, but then they also correlate in many cases with changes in DNA that are unique to a given individual.

The investigators used an algorithm that matches patterns of gene expression to variations at 1,000 single-DNA-base sites in the genome. It is an application of integrative biology that examines multiple dimensions of data (DNA and RNA) to better inform a given dimension (RNA).

"The relationship of DNA to RNA is like that of an orchestra and the symphony it plays," said Schadt describing the new technique. "The DNA (orchestra) remains the same, while the RNA pattern (quality of the music) changes in response to outside factors. The new technique is like hearing a symphony and deducing which instruments are in the orchestra, essentially unwinding the developmental process to trace tissue samples back to RNA and the gene that instructed it."

http://www.sciencedaily.com/releases/2012/04/120408212319.htm

Evolution at Sea: Long-Term Experiments Indicate Phytoplankton Can Adapt to Ocean Acidification

Scientists have now demonstrated the potential of unicellular algae to adapt to changing pH

ScienceDaily - Fossil fuel derived carbon dioxide has a serious impact on global climate but also a disturbing effect on the oceans, know as the other CO2 problem. When CO2 dissolves in seawater it forms carbonic acid and results in a drop in pH, the oceans acidify. A wealth of short-term experiments has shown that calcifying organisms, such as corals, clams and snails, but also micron size phytoplankton are affected by ocean acidification. The potential for organisms to cope with acidified oceanic conditions via evolutionary adaptations has so far been unresolved.

Scientists of the Helmholtz Centre for Ocean Research Kiel (GEOMAR) have now for the first demonstrated the potential of the unicellular algae Emiliania huxleyi to adapt to changing pH conditions and thereby at least partly to mitigate negative effects of ocean acidification. These results raised by the biologists Kai Lohbeck, Prof. Ulf Riebesell and Prof. Thorsten Reusch are published in the current issue of Nature Geoscience.

Experimental Emiliania huxleyi strains were isolated in Norwegian coastal waters and cultured in the laboratory under projected future ocean CO2 conditions. After about one year, which translates into 500 generations in this rapidly reproducing species, the biologists detected adaptation to high CO2 – adapted populations grew and calcified significantly better than non adapted control populations when tested under ocean acidification condition.

“From a biogeochemical perspective the most interesting finding was probably a partly restoration in calcification rates” GEOMAR scientist Prof. Ulf Riebesell notes. Emiliania huxleyi covers its cell surface with minute calcite scales that were found to decrease in weight under increased CO2 concentrations. “This is what we expected from the literature. But we were fascinated to find impaired calcification to partly recover after only 500 generations” says biologist Kai Lohbeck.

The evolutionary mechanisms proposed by the GEOMAR scientists are selection on different genotypes and the accumulation of novel beneficial mutations. Such an adaptation has not been shown earlier in any key phytoplankton species. “With this study we have shown for the fist time that evolutionary processes may have the potential to act on climate change relevant time scales and thereby mitigate negative effects of ongoing ocean acidification” says evolutionary biologist Thorsten Reusch and adds “These findings emphasize the need for a consideration of evolutionary processes in future assessment studies on the biological consequences of global change”.

Despite this finding, the GEOMAR scientists by no means think about an all-clear signal for ocean acidification. The potential for adaptive evolution may be large in rapidly reproducing species with large population sizes as is Emiliania huxleyi. “This is one reason why we have chosen this species for our studies” say the biologists. Long-lived species and especially those having only a few offspring per generation commonly have a much lower adaptive potential on climate change relevant time scales. “Earth history tells a convincing story about the limitations to evolutionary adaptation” Prof. Ulf Riebesell explains, “environmental changes comparable to what happens right now in the oceans have repeatedly resulted in mass extinctions, even though these changes were 10-100 times slower than what we observe today”.

Another open question is to what extent the evolutionary changes observed under laboratory conditions are transferable to the oceans where other environmental factors and ecological interactions play along. Therefore, the GEOMAR scientists already started to prepare follow-up experiments. In the framework of the BIOACID (Biological Impacts of Ocean ACIDification) project, funded by the German Federal Ministry of Education and Research (BMBF), the biologists plan to use the Kiel Off-Shore Mesocosms to investigate the adaptive potential of Emiliania huxleyi under natural conditions.

Kai T. Lohbeck, Ulf Riebesell, Thorsten B. H. Reusch. Adaptive evolution of a key phytoplankton species to ocean acidification. Nature Geoscience, 2012; DOI: 10.1038/NGEO1441

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