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Archive for the ‘Population Health Management, Nutrition and Phytochemistry’ Category


Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Research about marijuana and fertility is limited but some previous studies suggested that it might harm semen quality. Smoking of any type is also known to be a risk factor for male infertility. So, men who have smoked cannabis are expected to have worse measures of fertility but the data from a recent study suggested the opposite. The finding contradicts all conventional knowledge on how weed affects sperm. This may be because previous research typically focused on men with drug abuse history but this present study simply asked men if they had smoked more than two joints in their life.

 

Analysis of 1,143 semen samples from 662 men collected between 2000 and 2017 at the Fertility Clinic at Massachusetts General Hospital showed that those who had smoked weed at some point in their life had a mean sperm concentration of 62.7 million sperm per milliliter (mL) of ejaculate, while men who avoided marijuana entirely had mean concentrations of 45.4 million/mL. Added to this only 5% of weed smokers had sperm concentrations below the 15 million/mL threshold the World Health Organization has set for a “normal” sperm count, versus 12% of men who never smoked marijuana.

 

The study has some imperfections such as the participants are not necessarily representative of the general population. They were predominantly college educated men with a mean age of 36, and were all seeking treatment at a fertility center. Further research is needed to support the findings. Two possibilities are put forward by the researchers as the reason behind such data. The first is that low levels of marijuana could have a positive effect on the endocannabinoid system, the neurotransmitters in the nervous system that bind to cannabinoid receptors, and are known to regulate fertility. The second is that may be weed-smokers are just bigger risk takers and men with higher testosterone levels and thus have better sperm count.

 

But, there’s certainly no medical recommendation to smoke weed as a fertility treatment but this study, at least, suggests that a little marijuana doesn’t hurt and might benefit sperm production in some way. But, the researchers specified that their finding does not necessarily mean that smoking cannabis increases the chances of fatherhood.

 

References:

 

https://www.ncbi.nlm.nih.gov/pubmed/30726923

 

https://www.bloomberg.com/amp/news/articles/2019-02-06/cannabis-smoking-associated-with-higher-sperm-count-study-finds?__twitter_impression=true

 

https://qz.com/1543564/smoking-weed-linked-to-higher-sperm-count-in-a-harvard-study/

 

https://www.thestar.com.my/news/world/2019/02/06/cannabis-smoking-associated-with-higher-sperm-count-study-finds/

 

http://time.com/5520421/smoking-marijuana-sperm-fertility/

 

https://www.health.com/infertility/marijuana-sperm-count

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Stroke is a leading cause of death worldwide and the most common cause of long-term disability amongst adults, more particularly in patients with diabetes mellitus and arterial hypertension. Increasing evidence suggests that disordered physiological variables following acute ischaemic stroke, especially hyperglycaemia, adversely affect outcomes.

 

Post-stroke hyperglycaemia is common (up to 50% of patients) and may be rather prolonged, regardless of diabetes status. A substantial body of evidence has demonstrated that hyperglycaemia has a deleterious effect upon clinical and morphological stroke outcomes. Therefore, hyperglycaemia represents an attractive physiological target for acute stroke therapies.

 

However, whether intensive glycaemic manipulation positively influences the fate of ischaemic tissue remains unknown. One major adverse event of management of hyperglycaemia with insulin (either glucose-potassium-insulin infusions or intensive insulin therapy) is the occurrence of hypoglycaemia, which can also induce cerebral damage.

 

Doctors all over the world have debated whether intensive glucose management, which requires the use of IV insulin to bring blood sugar levels down to 80-130 mg/dL, or standard glucose control using insulin shots, which aims to get glucose below 180 mg/dL, lead to better outcomes after stroke.

 

A period of hyperglycemia is common, with elevated blood glucose in the periinfarct period consistently linked with poor outcome in patients with and without diabetes. The mechanisms that underlie this deleterious effect of dysglycemia on ischemic neuronal tissue remain to be established, although in vitro research, functional imaging, and animal work have provided clues.

 

While prompt correction of hyperglycemia can be achieved, trials of acute insulin administration in stroke and other critical care populations have been equivocal. Diabetes mellitus and hyperglycemia per se are associated with poor cerebrovascular health, both in terms of stroke risk and outcome thereafter.

 

Interventions to control blood sugar are available but evidence of cerebrovascular efficacy are lacking. In diabetes, glycemic control should be part of a global approach to vascular risk while in acute stroke, theoretical data suggest intervention to lower markedly elevated blood glucose may be of benefit, especially if thrombolysis is administered.

 

Both hypoglycaemia and hyperglycaemia may lead to further brain injury and clinical deterioration; that is the reason these conditions should be avoided after stroke. Yet, when correcting hyperglycaemia, great care should be taken not to switch the patient into hypoglycaemia, and subsequently aggressive insulin administration treatment should be avoided.

 

Early identification and prompt management of hyperglycaemia, especially in acute ischaemic stroke, is recommended. Although the appropriate level of blood glucose during acute stroke is still debated, a reasonable approach is to keep the patient in a mildly hyperglycaemic state, rather than risking hypoglycaemia, using continuous glucose monitoring.

 

The primary results from the Stroke Hyperglycemia Insulin Network Effort (SHINE) study, a large, multisite clinical study showed that intensive glucose management did not improve functional outcomes at 90 days after stroke compared to standard glucose therapy. In addition, intense glucose therapy increased the risk of very low blood glucose (hypoglycemia) and required a higher level of care such as increased supervision from nursing staff, compared to standard treatment.

 

References:

 

https://www.nih.gov/news-events/news-releases/nih-study-provides-answer-long-held-debate-blood-sugar-control-after-stroke

 

https://www.ncbi.nlm.nih.gov/pubmed/27873213

 

https://www.ncbi.nlm.nih.gov/pubmed/19342845

 

https://www.ncbi.nlm.nih.gov/pubmed/20491782

 

https://www.ncbi.nlm.nih.gov/pubmed/21211743

 

https://www.ncbi.nlm.nih.gov/pubmed/18690907

 

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Morbid Obesity linked to socioeconomic status was in a Twin Pairs Research on effects of genes and environment in 560 common conditions – Disease and Health by ZIP code (Environment) and genetic code (Human Genome)

Reporter: Aviva Lev-Ari, PhD, RN

 

  • Senior study author Chirag Patel, assistant professor of biomedical informatics in the Blavatnik Institute at HMS.
  • Co-investigators were Braden Tierney and Arjun Manrai of Harvard Medical School, and
  • Jian Yang and Peter Visscher of the University of Queensland, Australia.

Data sets for the study were provided by Aetna insurance company. Aetna had no funding role in the study. The research was supported by the Australian National Health and Medical Research Council (grants 1078037 and 1113400), National Science Foundation (grant 1636870), and Sylvia and Charles Viertel Charitable Foundation.

 

Detailed study results available here: http://apps.chiragjpgroup.org/catch/

Conclusions 

Nearly 40 percent of the diseases in the study (225 of 560) had a genetic component, while 25 percent (138) were driven at least in part by factors stemming from sharing the same household, social influences, and the like. Cognitive disorders demonstrated the greatest degree of heritability — four out of five diseases showed a genetic component — while connective tissue diseases had the lowest degree of genetic influence. Of all disease categories, eye disorders carried the highest degree of environmental influence, with 27 of 42 diseases showing such effect. They were followed by respiratory diseases, with 34 out of 48 conditions showing an effect from sharing a household. The disease category with lowest environmental influence was reproductive illnesses, with three of 18 conditions showing such effect, and cognitive conditions, with two out of five showing an influence.

Overall, socioeconomic status, climate conditions, and air quality in each twin pair’s ZIP code had a far weaker effect on disease than genes and shared environment — a composite measure of external, nongenetic influences including family and lifestyle, household, and neighborhood.

In total, 145 of 560 diseases were modestly influenced by socio-economic status derived by ZIP code. Thirty-six diseases were influenced at least in part by air quality, and 117 were affected by changes in temperature. The condition with the strongest potential link to socioeconomic status was morbid obesity. While obesity undoubtedly has a genetic component, the researchers said, the findings raise an important question about the influence of environment on genetic predispositions.

“This finding opens up a whole slew of questions, including whether and how a change in socioeconomic status and lifestyle might compare against genetic predisposition to obesity,” Patel said.

Lead poisoning was, not surprisingly, entirely driven by environment. Conditions such as flu and Lyme disease were, again unsurprisingly, affected by differences in climate.

When researchers looked at classes of diseases by monthly health care spending, they found that both genes and environment significantly contributed to cost of care, with the two being nearly equal drivers of spending. Almost 60 percent of monthly health spending could be predicted by analyzing genetic and environmental factors.

Large-scale analysis like this study can help forecast long-term spending for various conditions and inform resource allocation and policy decisions, the researchers said.

Detailed study results available here: http://apps.chiragjpgroup.org/catch/

SOURCE

http://apps.chiragjpgroup.org/catch/

https://news.harvard.edu/gazette/story/2019/01/researchers-able-to-determine-the-effects-of-genes-and-environment-in-560-common-conditions/?utm_source=SilverpopMailing&utm_medium=email&utm_campaign=Daily%20Gazette%202%20stories%201%20event%20(no%20Seen%20or%20Heard)%20(1)

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Benefits of Fiber in Diet

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

UPDATED on 1/15/2019

This is How Much Daily Fiber to Eat for Better Health – More appears better in meta-analysis — as in more than 30 g/day

by Ashley Lyles, Staff Writer, MedPage Today

In the systematic review, observational data showed a 15% to 30% decline in cardiovascular-related death, all-cause mortality, and incidence of stroke, coronary heart disease, type 2 diabetes, and colorectal cancer among people who consumed the most dietary fiber compared to those consuming the lowest amounts.

Whole grain intake yielded similar findings.

Risk reduction associated with a range of critical outcomes was greatest when daily intake of dietary fibre was between 25 g and 29 g. Dose-response curves suggested that higher intakes of dietary fibre could confer even greater benefit to protect against cardiovascular diseases, type 2 diabetes, and colorectal and breast cancer.

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(18)31809-9.pdf

Eating more dietary fiber was linked with lower risk of disease and death, a meta-analysis showed.

According to observational studies, risk was reduced most for a range of critical outcomes from all-cause mortality to stroke when daily fiber consumption was between 25 grams and 29 grams, reported Jim Mann, PhD, of University of Otago in Dunedin, New Zealand, and colleagues in The Lancet.

By upping daily intake to 30 grams or more, people had even greater prevention of certain conditions: colorectal and breast cancer, type 2 diabetes, and cardiovascular diseases, according to dose-response curves the authors created.

Quantitative guidelines relating to dietary fiber have not been available, the researchers said. With the GRADE method, they determined that there was moderate and low-to-moderate certainty of evidence for the benefits of dietary fiber consumption and whole grain consumption, respectively.

Included in the systematic review were 58 clinical trials and 185 prospective studies for a total of 4,635 adult participants with 135 million person-years of information (one trial in children was included, but analyzed separately from adults). Trials and prospective studies assessing weight loss, supplement use, and participants with a chronic disease were excluded.

 

Food is digested by bathing in enzymes that break down its molecules. Those molecular fragments then pass through the gut wall and are absorbed in our intestines. But our bodies make a limited range of enzymes, so that we cannot break down many of the tough compounds in plants. The term “dietary fiber” refers to those indigestible molecules. These dietary fibers are indigestible only to us. The gut is coated with a layer of mucus, on which sits a carpet of hundreds of species of bacteria, part of the human microbiome. Some of these microbes carry the enzymes needed to break down various kinds of dietary fibers.

 

Scientists at the University of Gothenburg in Sweden are running experiments that are yielding some important new clues about fiber’s role in human health. Their research indicates that fiber doesn’t deliver many of its benefits directly to our bodies. Instead, the fiber we eat feeds billions of bacteria in our guts. Keeping them happy means our intestines and immune systems remain in good working order. The scientists have recently reported that the microbes are involved in the benefits obtained from the fruits-and-vegetables diet. Research proved that low fiber diet decreases the gut bacteria population by tenfold.

 

Along with changes to the microbiome there were also rapid changes observed in the experimental mice. Their intestines got smaller, and its mucus layer thinner. As a result, bacteria wound up much closer to the intestinal wall, and that encroachment triggered an immune reaction. After a few days on the low-fiber diet, mouse intestines developed chronic inflammation. After a few weeks, they started putting on fat and developing higher blood sugar levels. Inflammation can help fight infections, but if it becomes chronic, it can harm our bodies. Among other things, chronic inflammation may interfere with how the body uses the calories in food, storing more of it as fat rather than burning it for energy.

 

In a way fiber benefits human health is by giving, indirectly, another source of food. When bacteria finished harvesting the energy in the dietary fiber, they cast off the fragments as waste. That waste — in the form of short-chain fatty acids — is absorbed by intestinal cells, which use it as fuel. But the gut’s microbes do more than just make energy. They also send messages. Intestinal cells rely on chemical signals from the bacteria to work properly. The cells respond to the signals by multiplying and making a healthy supply of mucus. They also release bacteria-killing molecules. By generating these responses, gut bacteria help to maintain a peaceful coexistence with the immune system. They rest on the gut’s mucus layer at a safe distance from the intestinal wall. Any bacteria that wind up too close get wiped out by antimicrobial poisons.

 

A diet of fiber-rich foods, such as fruits and vegetables, reduces the risk of developing diabetes, heart disease and arthritis. Eating more fiber seems to lower people’s mortality rate, whatever be the cause. Researchers hope that they will learn more about how fiber influences the microbiome to use it as a way to treat disorders. Lowering inflammation with fiber may also help in the treatment of immune disorders such as inflammatory bowel disease. Fiber may also help reverse obesity. They found that fiber supplements helped obese people to lose weight. It’s possible that each type of fiber feeds a particular set of bacteria, which send their own important signals to our bodies.

 

References:

 

https://www.nytimes.com/2018/01/01/science/food-fiber-microbiome-inflammation.html

 

 

https://www.ncbi.nlm.nih.gov/pubmed/29276171

 

https://www.ncbi.nlm.nih.gov/pubmed/29276170

 

https://www.ncbi.nlm.nih.gov/pubmed/29486139

 

https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/fiber/art-20043983

 

https://nutritiouslife.com/eat-empowered/high-fiber-diet/

 

http://www.eatingwell.com/article/287742/10-amazing-health-benefits-of-eating-more-fiber/

 

http://www.cookinglight.com/eating-smart/nutrition-101/what-is-a-high-fiber-diet

 

https://www.helpguide.org/articles/healthy-eating/high-fiber-foods.htm

 

https://www.gicare.com/diets/high-fiber-diet/

 

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Decline in Sperm Count – Epigenetics, Well-being and the Significance for Population Evolution and Demography

 

Dr. Marc Feldman, Expert Opinion on the significance of Sperm Count Decline on the Future of Population Evolution and Demography

Dr. Sudipta Saha, Effects of Sperm Quality and Quantity on Human Reproduction

Dr. Aviva Lev-Ari, Psycho-Social Effects of Poverty, Unemployment and Epigenetics on Male Well-being, Physiological Conditions affecting Sperm Quality and Quantity

 

UPDATED on 2/3/2018

Nobody Really Knows What Is Causing the Overdose Epidemic, But Here Are A Few Theories

https://www.buzzfeed.com/danvergano/whats-causing-the-opioid-crisis?utm_term=.kbJPMgaQo4&utm_source=BrandeisNOW%2BWeekly&utm_campaign=58ada49a84-EMAIL_CAMPAIGN_2018_01_29&utm_medium=email#.uugW6mx1dG

 

Recent studies concluded via rigorous and comprehensive analysis found that Sperm Count (SC) declined 52.4% between 1973 and 2011 among unselected men from western countries, with no evidence of a ‘leveling off’ in recent years. Declining mean SC implies that an increasing proportion of men have sperm counts below any given threshold for sub-fertility or infertility. The high proportion of men from western countries with concentration below 40 million/ml is particularly concerning given the evidence that SC below this threshold is associated with a decreased monthly probability of conception.

1.Temporal trends in sperm count: a systematic review and meta-regression analysis 

Hagai Levine, Niels Jørgensen, Anderson Martino‐Andrade, Jaime Mendiola, Dan Weksler-Derri, Irina Mindlis, Rachel Pinotti, Shanna H SwanHuman Reproduction Update, July 25, 2017, doi:10.1093/humupd/dmx022.

Link: https://academic.oup.com/humupd/article-lookup/doi/10.1093/humupd/dmx022.

2. Sperm Counts Are Declining Among Western Men – Interview with Dr. Hagai Levine

https://news.afhu.org/news/sperm-counts-are-declining-among-western-men?utm_source=Master+List&utm_campaign=dca529d919-EMAIL_CAMPAIGN_2017_07_27&utm_medium=email&utm_term=0_343e19a421-dca529d919-92801633

3. Trends in Sperm Count – Biological Reproduction Observations

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

4. Long, mysterious strips of RNA contribute to low sperm count – Long non-coding RNAs can be added to the group of possible non-structural effects, possibly epigenetic, that might regulate sperm counts.

http://casemed.case.edu/cwrumed360/news-releases/release.cfm?news_id=689

https://scienmag.com/long-mysterious-strips-of-rna-contribute-to-low-sperm-count/

Dynamic expression of long non-coding RNAs reveals their potential roles in spermatogenesis and fertility

Published: 29 July 2017
Thus, we postulated that some lncRNAs may also impact mammalian spermatogenesis and fertility. In this study, we identified a dynamic expression pattern of lncRNAs during murine spermatogenesis. Importantly, we identified a subset of lncRNAs and very few mRNAs that appear to escape meiotic sex chromosome inactivation (MSCI), an epigenetic process that leads to the silencing of the X- and Y-chromosomes at the pachytene stage of meiosis. Further, some of these lncRNAs and mRNAs show strong testis expression pattern suggesting that they may play key roles in spermatogenesis. Lastly, we generated a mouse knock out of one X-linked lncRNA, Tslrn1 (testis-specific long non-coding RNA 1), and found that males carrying a Tslrn1 deletion displayed normal fertility but a significant reduction in spermatozoa. Our findings demonstrate that dysregulation of specific mammalian lncRNAs is a novel mechanism of low sperm count or infertility, thus potentially providing new biomarkers and therapeutic strategies.

This article presents two perspectives on the potential effects of Sperm Count decline.

One Perspective identifies Epigenetics and male well-being conditions

  1. as a potential explanation to the Sperm Count decline, and
  2. as evidence for decline in White male longevity in certain geographies in the US since the mid 80s.

The other Perspective, evaluates if Sperm Count Decline would have or would not have a significant long term effects on Population Evolution and Demography.

The Voice of Prof. Marc Feldman, Stanford University – Long term significance of Sperm Count Decline on Population Evolution and Demography

Poor sperm count appears to be associated with such demographic statistics as life expectancy (1), infertility (2), and morbidity (3,4). The meta-analysis by Levine et al. (5) focuses on the change in sperm count of men from North America, Europe, Australia, and New Zealand, and shows a more than 50% decline between 1973 and 2011. Although there is no analysis of potential environmental or lifestyle factors that could contribute to the estimated decline in sperm count, Levine et al. speculate that this decline could be a signal for other negative changes in men’s health.

Because this study focuses mainly on Western men, this remarkable decline in sperm count is difficult to associate with any change in actual fertility, that is, number of children born per woman. The total fertility rate in Europe, especially Italy, Spain, and Germany, has slowly declined, but age at first marriage has increased at the same time, and this increase may be more due to economic factors than physiological changes.

Included in Levine et al.’s analysis was a set of data from “Other” countries from South America, Asia, and Africa. Sperm count in men from these countries did not show significant trends, which is interesting because there have been strong fertility declines in Asia and Africa over the same period, with corresponding increases in life expectancy (once HIV is accounted for).

What can we say about the evolutionary consequences for humans of this decrease? The answer depends on the minimal number of sperm/ml/year that would be required to maintain fertility (per woman) at replacement level, say 2.1 children, over a woman’s lifetime. Given the smaller number of ova produced per woman, a change in the ovulation statistics of women would be likely to play a larger role in the total fertility rate than the number of sperm/ejaculate/man. In other words, sperm count alone, absent other effects on mortality during male reproductive years, is unlikely to tell us much about human evolution.

Further, the major declines in fertility over the 38-year period covered by Levine et al. occurred in China, India, and Japan. Chinese fertility has declined to less than 1.5 children per woman, and in Japan it has also been well below 1.5 for some time. These declines have been due to national policies and economic changes, and are therefore unlikely to signal genetic changes that would have evolutionary ramifications. It is more likely that cultural changes will continue to be the main drivers of fertility change.

The fastest growing human populations are in the Muslim world, where fertility control is not nearly as widely practiced as in the West or Asia. If this pattern were to continue for a few more generations, the cultural evolutionary impact would swamp any effects of potentially declining sperm count.

On the other hand, if the decline in sperm count were to be discovered to be associated with genetic and/or epigenetic phenotypic effects on fetuses, newborns, or pre-reproductive humans, for example, due to stress or obesity, then there would be cause to worry about long-term evolutionary problems. As Levine et al. remark, “decline in sperm count might be considered as a ‘canary in the coal mine’ for male health across the lifespan”. But to date, there is little evidence that the evolutionary trajectory of humans constitutes such a “coal mine”.

References

  1. Jensen TK, Jacobsen R, Christensen K, Nielsen NC, Bostofte E. 2009. Good semen quality and life expectancy: a cohort study of 43,277 men. Am J Epidemiol 170: 559-565.
  2. Eisenberg ML, Li S, Behr B, Cullen MR, Galusha D, Lamb DJ, Lipshultz LI. 2014. Semen quality, infertility and mortality in the USA. Hum Reprod 29: 1567-1574.
  3. Eisenberg ML, Li S, Cullen MR, Baker LC. 2016. Increased risk of incident chronic medical conditions in infertile men: analysis of United States claims data. Fertil Steril 105: 629-636.
  4. Latif T, Kold Jensen T, Mehlsen J, Holmboe SA, Brinth L, Pors K, Skouby SO, Jorgensen N, Lindahl-Jacobsen R. Semen quality is a predictor of subsequent morbidity. A Danish cohort study of 4,712 men with long-term follow-up. Am J Epidemiol. Doi: 10.1093/aje/kwx067. (Epub ahead of print]
  5. Levine H, Jorgensen N, Martino-Andrade A, Mendiola J, Weksler-Derri D, Mindlis I, Pinotti R, Swan SH. 2017. Temporal trends in sperm count: a systematic review and meta-regression analysis. Hum Reprod Update pp. 1-14. Doi: 10.1093/humupd/dmx022.

SOURCE

From: Marcus W Feldman <mfeldman@stanford.edu>

Date: Monday, July 31, 2017 at 8:10 PM

To: Aviva Lev-Ari <aviva.lev-ari@comcast.net>

Subject: Fwd: text of sperm count essay

Psycho-Social Effects of Poverty, Unemployment and Epigenetics on Male Well-being, Physiological Conditions as POTENTIAL effects on Sperm Quality and Quantity and Evidence of its effects on Male Longevity

The Voice of Carol GrahamSergio Pinto, and John Juneau II , Monday, July 24, 2017, Report from the Brookings Institute

  1. The IMPACT of Well-being, Stress induced by Worry, Pain, Perception of Hope related to Employment and Lack of employment on deterioration of Physiological Conditions as evidence by Decrease Longevity

  2. Epigenetics and Environmental Factors

The geography of desperation in America

Carol GrahamSergio Pinto, and John Juneau II Monday, July 24, 2017, Report from the Brookings Institute

In recent work based on our well-being metrics in the Gallup polls and on the mortality data from the Centers for Disease Control and Prevention, we find a robust association between lack of hope (and high levels of worry) among poor whites and the premature mortality rates, both at the individual and metropolitan statistical area (MSA) levels. Yet we also find important differences across places. Places come with different economic structures and identities, community traits, physical environments and much more. In the maps below, we provide a visual picture of the differences in in hope for the future, worry, and pain across race-income cohorts across U.S. states. We attempted to isolate the specific role of place, controlling for economic, socio-demographic, and other variables.

One surprise is the low level of optimism and high level of worry in the minority dense and generally “blue” state of California, and high levels of pain and worry in the equally minority dense and “blue” states of New York and Massachusetts. High levels of income inequality in these states may explain these patterns, as may the nature of jobs that poor minorities hold.

We cannot answer many questions at this point. What is it about the state of Washington, for example, that is so bad for minorities across the board? Why is Florida so much better for poor whites than it is for poor minorities? Why is Nevada “good” for poor white optimism but terrible for worry for the same group? One potential issue—which will enter into our future analysis—is racial segregation across places. We hope that the differences that we have found will provoke future exploration. Readers of this piece may have some contributions of their own as they click through the various maps, and we welcome their input. Better understanding the role of place in the “crisis” of despair facing our country is essential to finding viable solutions, as economic explanations, while important, alone are not enough.

https://www.brookings.edu/research/the-geography-of-desperation-in-america/?utm_medium=social&utm_source=facebook&utm_campaign=global

 

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Blood Pressure Lowering

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Data analysis and publication of landmark NIH blood pressure study confirm that lower blood pressure target can reduce cardiovascular disease, deaths

http://www.nih.gov/news-events/news-releases/data-analysis-publication-landmark-nih-blood-pressure-study-confirm-lower-blood-pressure-target-can-reduce-cardiovascular-disease-deaths

 

NIH-supported researchers are reporting more details on a landmark study that announced preliminary findings in September showing a lower blood pressure target can save lives and reduce the risk of cardiovascular disease in a group of non-diabetic adults 50 years and older with high blood pressure. Results of the Systolic Blood Pressure Intervention Trial (SPRINT) appear in the current online issue of the New England Journal of Medicine and were discussed today at the American Heart Association 2015 Scientific Sessions in Orlando.

The study confirms that, in adults 50 years and older with high blood pressure, targeting a systolic blood pressure of less than 120 millimeters of mercury (mm Hg) reduced rates of cardiovascular events, such as heart attack and heart failure, as well as stroke, by 25 percent. Additionally, this target reduced the risk of death by 27 percent—as compared to a target systolic pressure of 140 mm Hg.

“SPRINT is part of a proud legacy of NIH-funded clinical trials that will change clinical practice and save lives for decades to come. These results reinforce the compelling public health importance of enhancing the awareness, treatment and control of hypertension in this country and around the world,” said Gary H. Gibbons, M.D., director of the National Heart, Lung, and Blood Institute (NHLBI), the primary sponsor of SPRINT.

The SPRINT study, which began in the fall of 2009, included more than 9,300 participants age 50 and older, recruited from about 100 medical centers and clinical practices throughout the United States and Puerto Rico. About 36 percent of participants were women, 58 percent were white, 30 percent were African-American, and 11 percent were Hispanic. The SPRINT study did not include patients with diabetes, prior stroke, or polycystic kidney disease, as other NIH trials were studying those particular populations. Approximately 28 percent were 75 or older and 28 percent had chronic kidney disease. The study tested a strategy of using blood pressure medications to achieve the targeted goals of less than 120 mm Hg (intensive treatment group) versus 140 mm Hg (standard treatment group). The NIH stopped the blood pressure intervention in August—a year earlier than planned—after it became apparent that this more intensive intervention was beneficial.

“When the benefits of the stronger intervention became apparent in SPRINT, we made a commitment to rapid public health communication and peer-reviewed publication of the study results,” Dr. Gibbons said. “We are pleased to present the details of the study’s potentially lifesaving findings at this time.”

In their report, investigators provided detailed data showing that both cardiovascular deaths and overall deaths were lower in the intensive treatment group.

Certain types of serious consequences were more common in the intensive group, including low blood pressure, fainting, electrolyte abnormalities, and acute kidney damage. However, other serious adverse events associated with lower blood pressure, such as slow heart rate and falls with injuries, did not increase in the intensive group. In patients with chronic kidney disease, there was no difference in the rate of serious decline in kidney function between the two blood pressure goal groups.

“The benefits of more intensive blood pressure lowering exceeded the potential for harm, regardless of gender or race/ethnicity,” said study co-author Paul Whelton, M.D., of Tulane University School of Public Health and Tropical Medicine in New Orleans, Louisiana. He is chair of the SPRINT Steering Committee.

In addition to its primary cardiovascular outcome, the study continues to examine kidney disease, cognitive function, and dementia among the SPRINT participants; however, these results are not yet available as additional information will be collected and analyzed over the next year.

“Although the study provides strong evidence that a lower blood pressure target saves lives, patients and their health care providers may want to wait to see how guideline groups incorporate this study and other scientific reports into any future hypertension guidelines. In the meantime, patients should talk to their health care providers to determine whether this lower goal is best for their individual care,” said study co-author Lawrence Fine, M.D., Chief, Clinical Applications and Prevention Branch at NHLBI.

“It’s also important to remember that healthy lifestyle changes can make a difference in controlling high blood pressure,” Dr. Fine added. He emphasized the importance of following a healthy diet, being physically active, maintaining a healthy weight, as well as learning to check your blood pressure.

In addition to primary sponsorship by the NHLBI, SPRINT is co-sponsored by the NIH’s National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute of Neurological Disorders and Stroke, and the National Institute on Aging.

Part of the National Institutes of Health, the National Heart, Lung, and Blood Institute (NHLBI) plans, conducts, and supports research related to the causes, prevention, diagnosis, and treatment of heart, blood vessel, lung, and blood diseases; and sleep disorders. The Institute also administers national health education campaigns on women and heart disease, healthy weight for children, and other topics. NHLBI press releases and other materials are available online at http://www.nhlbi.nih.gov.

About the National Institutes of Health (NIH): NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.

NIH…Turning Discovery Into Health®

Landmark NIH study shows intensive blood pressure management may save lives

Embargoed for Release:

September 11, 2015, 10:30 AM EDT

Lower blood pressure target greatly reduces cardiovascular complications and deaths in older adults

More intensive management of high blood pressure, below a commonly recommended blood pressure target, significantly reduces rates of cardiovascular disease, and lowers risk of death in a group of adults 50 years and older with high blood pressure. This is according to the initial results of a landmark clinical trial sponsored by the National Institutes of Health called the Systolic Blood Pressure Intervention Trial (SPRINT). The intervention in this trial, which carefully adjusts the amount or type of blood pressure medication to achieve a target systolicpressure of 120 millimeters of mercury (mm Hg), reduced rates of cardiovascular events, such as heart attack and heart failure, as well as stroke, by almost a third and the risk of death by almost a quarter, as compared to the target systolic pressure of 140 mm Hg.

“This study provides potentially lifesaving information that will be useful to health care providers as they consider the best treatment options for some of their patients, particularly those over the age of 50,” said Gary H. Gibbons, M.D., director of the National Heart, Lung, and Blood Institute (NHLBI), the primary sponsor of SPRINT. “We are delighted to have achieved this important milestone in the study in advance of the expected closure date for the SPRINT trial and look forward to quickly communicating the results to help inform patient care and the future development of evidence-based clinical guidelines.”

High blood pressure, or hypertension, is a leading risk factor for heart disease, stroke, kidney failure, and other health problems. An estimated 1 in 3 people in the United States has high blood pressure.

The SPRINT study evaluates the benefits of maintaining a new target for systolic blood pressure, the top number in a blood pressure reading, among a group of patients 50 years and older at increased risk for heart disease or who have kidney disease. A systolic pressure of 120 mm Hg, maintained by this more intensive blood pressure intervention, could ultimately help save lives among adults age 50 and older who have a combination of high blood pressure and at least one additional risk factor for heart disease, the investigators say.

The SPRINT study, which began in the fall of 2009, includes more than 9,300 participants age 50 and older, recruited from about 100 medical centers and clinical practices throughout the United States and Puerto Rico. It is the largest study of its kind to date to examine how maintaining systolic blood pressure at a lower than currently recommended level will impact cardiovascular and kidney diseases. NIH stopped the blood pressure intervention earlier than originally planned in order to quickly disseminate the significant preliminary results.

The study population was diverse and included women, racial/ethnic minorities, and the elderly.  The investigators point out that the SPRINT study did not include patients with diabetes, prior stroke, or polycystic kidney disease, as other research included those populations.

When SPRINT was designed, the well-established clinical guidelines recommended a systolic blood pressure of less than 140 mm Hg for healthy adults and 130 mm Hg for adults with kidney disease or diabetes. Investigators designed SPRINT to determine the potential benefits of achieving systolic blood pressure of less than 120 mm Hg for hypertensive adults 50 years and older who are at risk for developing heart disease or kidney disease.

Between 2010 and 2013, the SPRINT investigators randomly divided the study participants into two groups that differed according to targeted levels of blood pressure control. The standard group received blood pressure medications to achieve a target of less than 140 mm Hg. They received an average of two different blood pressure medications. The intensive treatment group received medications to achieve a target of less than 120 mm Hg and received an average of three medications.

“Our results provide important evidence that treating blood pressure to a lower goal in older or high-risk patients can be beneficial and yield better health results overall,” said Lawrence Fine, M.D., chief, Clinical Applications and Prevention Branch at NHLBI. “But patients should talk to their doctor to determine whether this lower goal is best for their individual care.”

The study is also examining kidney disease, cognitive function, and dementia among the patients; however, those results are still under analysis and are not yet available as additional information will be collected over the next year.  The primary results of the trial will be published within the next few months.

In addition to primary sponsorship by the NHLBI, SPRINT is co-sponsored by the NIH’s National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute of Neurological Disorders and Stroke, and the National Institute on Aging.

Supplemental Information

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The good, the bad and the ugly of sulfur and volcanic activity

Larry H Bernstein, MD, FCAP, Curator

LPBI

 

Climate change deniers have promulgated much ignorance about the planet and our life on earth.  Nevertheless, I shall deal with geophysical and geochemical issues and indirectly, climate change in this portion of the discussion.  The good, the bad, and the ugly has everything to due with the elements and to life on earth.  This is the case, regardless of claims propagated by the tobacco and the carbon fuels interests.  I shall proceed as I have done in the previous discussions.

Is a Lack of Water to Blame for the Conflict in Syria?

A 2006 drought pushed Syrian farmers to migrate to urban centers, setting the stage for massive uprisings

By Joshua Hammer

SMITHSONIAN MAGAZINE

http://www.smithsonianmag.com/innovation/is-a-lack-of-water-to-blame-for-the-conflict-in-syria-72513729

 

An Iraqi girl stands on former marshland, drained in the 1990s because of politically motivated water policies. (Essam Al-Sudani / AFP / Getty Images)
http://thumbs.media.smithsonianmag.com//filer/Scare-Tactics-Iraqi-girl-631.jpg__800x600_q85_crop.jpg

The world’s earliest documented water war happened 4,500 years ago, when the armies of Lagash and Umma, city-states near the junction of the Tigris and Euphrates rivers, battled with spears and chariots after Umma’s king drained an irrigation canal leading from the Tigris. “Enannatum, ruler of Lagash, went into battle,” reads an account carved into an ancient stone cylinder, and “left behind 60 soldiers [dead] on the bank of the canal.”

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Water loss documented by the Gravity Recovery and Climate Experiment (GRACE), a pair of satellites operated by NASA and Germany’s aerospace center, suggests water-related conflict could be brewing on the riverbank again. GRACE measured groundwater usage between 2003 and 2009 and found that the Tigris-Euphrates Basin—comprising Turkey, Syria, Iraq and western Iran—is losing water faster than any other place in the world except northern India . During those six years, 117 million acre-feet of stored freshwater vanished from the region as a result of dwindling rainfall and poor water management policies. That’s equal to all the water in the Dead Sea. GRACE’s director, Jay Famiglietti, a hydrologist at the University of California, Irvine, calls the data “alarming.”

While the scientists captured dropping water levels, political experts have observed rising tensions. In Iraq, the absence of a strong government since 2003, drought and shrinking aquifers have led to a recent spate of assassinations of irrigation department officials and clashes between rural clans. Some experts say that these local feuds could escalate into full-scale armed conflicts .

In Syria, a devastating drought beginning in 2006 forced many farmers to abandon their fields and migrate to urban centers. There’s some evidence that the migration fueled the civil war there, in which 80,000 people have died. “You had a lot of angry, unemployed men helping to trigger a revolution,” says Aaron Wolf, a water management expert at Oregon State University, who frequently visits the Middle East.

Tensions between nations are also high. Since 1975, Turkey’s dam and hydro­power construction has cut water flow to Iraq by 80 percent and to Syria by 40 percent. Syria and Iraq have accused Turkey of hoarding water.

Hydrologists say that the countries need to find alternatives to sucking the aquifers dry—perhaps recycling wastewater or introducing desalination—and develop equitable ways of sharing their rivers. “Water doesn’t know political boundaries. People have to get together and work,” Famiglietti says. One example lies nearby, in an area not known for cross-border cooperation. Israeli and Jordanian officials met last year for the first time in two decades to discuss rehabilitating the nearly dry Jordan River, and Israel has agreed to release freshwater down the river.

“It could be a model” for the Tigris-Euphrates region, says Gidon Bromberg, a co-director of Friends of the Earth Middle East, who helped get the countries together. Wolf, too, remains optimistic, noting that stress can encourage compromise.

History might suggest a way: The world’s first international water treaty, a cuneiform tablet now hanging in the Louvre, ended the war between Lagash and Umma.

 

http://static.guim.co.uk/ni/1404220722088/Iraq_water_dams.svg

“Rebel forces are targeting water installations to cut off supplies to the largely Shia south of Iraq,” says Matthew Machowski, a Middle East security researcher at the UK houses of parliament and Queen Mary University of London.

“It is already being used as an instrument of war by all sides. One could claim that controlling water resources in Iraq is even more important than controlling the oil refineries, especially in summer. Control of the water supply is fundamentally important. Cut it off and you create great sanitation and health crises,” he said

Isis now controls the Samarra barrage west of Baghdad on the River Tigris and areas around the giant Mosul Dam, higher up on the same river. Because much of Kurdistan depends on the dam, it is strongly defended by Kurdish peshmerga forces and is unlikely to fall without a fierce fight, says Machowski.

Iraqi troops were rushed to defend the massive 8km-long Haditha Dam and its hydroelectrical works on the Euphrates to stop it falling into the hands of Isis forces. Were the dam to fall, say analysts, Isis would control much of Iraq’s electricity and the rebels might fatally tighten their grip on Baghdad.

Isis fighters in Fallujah captured the smaller Nuaimiyah Dam on the Euphrates and deliberately diverted its water to “drown” government forces in the surrounding area. Millions of people in the cities of Karbala, Najaf, Babylon and Nasiriyah had their water cut off but the town of Abu Ghraib was catastrophically flooded along with farms and villages over 200 square miles. According to the UN, around 12,000 families lost their homes.

Earlier, Kurdish forces reportedly diverted water supplies from the Mosul Dam. Equally, Turkey has been accused of reducing flows to the giant Lake Assad, Syria’s largest body of fresh water, to cut off supplies to Aleppo, and Isis forces have reportedly targeted water supplies in the refugee camps set up for internally displaced people.

Iraqis fled from Mosul after Isis cut off power and water and only returned when they were restored, says Machowski. “When they restored water supplies to Mosul, the Sunnis saw it as liberation. Control of water resources in the Mosul area is one reason why people returned,” said Machowski.

Both Isis forces and President Assad’s army are said to have used water tactics to control the city of Aleppo. The Tishrin Dam on the Euphrates, 60 miles east of the city, was captured by Isis in November 2012.

“The deliberate targeting of water supply networks … is now a daily occurrence in the conflict. The water pumping station in Al-Khafsah, Aleppo, stopped working on 10 May, cutting off water supply to half of the city.

https://i.guim.co.uk/img/static/sys-images/Guardian/Pix/pictures/2014/7/2/1404300629581/

A satellite view showing the two main rivers running from Turkey through Syria and Iraq. Credits: MODIS/NASA

The Euphrates River, the Middle East’s second longest river, and the Tigris, have historically been at the centre of conflict. In the 1980s, Saddam Hussein drained 90% of the vast Mesopotamian marshes that were fed by the two rivers to punish the Shias who rose up against his regime. Since 1975, Turkey’s dam and hydropower constructions on the two rivers have cut water flow to Iraq by 80% and to Syria by 40%. Both Syria and Iraq have accused Turkey of hoarding water and threatening their water supply.

http://www.irinnews.org/photo/

The Barada River, shown here in Damascus, is the only notable river flowing entirely within Syrian territory. The city’s water supplies are under huge strain

DAMASCUS, 25 March 2010 (IRIN) – Poor planning and management, wasteful irrigation systems, intensive wheat and cotton farming and a rapidly growing population are straining water resources in Syria in a year which has seen unprecedented internal displacement as a result of drought in eastern and northeastern parts of the country.

In 2007 Syria consumed 19.2 billion cubic metres of water – 3.5 billion more than the amount of water replenished naturally, with the deficit coming from groundwater and reservoirs, according to the Ministry of Irrigation.

Agriculture accounts for almost 90 percent of the country’s water consumption, according to government and private sector.

Agricultural policies encourage water-hungry wheat and cotton cultivation, and inefficient irrigation methods mean much water is wasted.

 

South Asia is a desperately water-insecure region, and India’s shortages are part of a wider continental crisis. According to a recent report authored by UN climate scientists, coastal areas in Asia will be among the worst affected by climate change. Hundreds of millions of people across East, Southeast and South Asia, the report concluded, will be affected by flooding, droughts, famine, increases in the costs of food and energy, and rising sea levels.

Groundwater serves as a vital buffer against the volatility of monsoon rains, and India’s falling water table therefore threatens catastrophe. 60 percent of north India’s irrigated agriculture is dependent on ground water, as is 85 percent of the region’s drinking water. The World Bank predicts that India only has 20 years before its aquifers will reach “critical condition” – when demand for water will outstrip supply – an eventuality that will devastate the region’s food security, economic growth and livelihoods.

Analysts fear that growing competition for rapidly dwindling natural resources will trigger inter-state or intra-state conflict. China and India continue to draw on water sources that supply the wider region, and a particularly concerning flashpoint is the Indus River Valley basin that spans India and Pakistan. The river’s waters are vital to the economies of areas on both sides of the border and a long-standing treaty, agreed by Pakistan and India in 1960, governs rights of access. But during the “dry season,” between October and March, water levels fall to less than half of those seen during the remainder of the year. The fear is that cooperation over access to the Indus River will fray as shortages become more desperate.

http://cdn1.pri.org/sites/default/files/styles/story_main/public/story/images/IMG_5937.jpeg

Farm worker heading for the paddy fields at Gubinder Singh’s farm

The Indo-Gangetic Basin, which lies at the foothills of the Himalayas, is one of the areas in the world facing a huge water crisis.  The Basin spans from Pakistan, across Northern India into Bangladesh. Apart from runoff from mountainous streams and glaciers, it also holds one of the largest underground bodies of water in the world. But it’s also in one of the most populous regions of the world, with more than a billion people living on the subcontinent.  Still, parts of the region are well-resourced when it comes to water supplies – like the Indian state of Punjab, which has three rivers running through it and a network of canals in some parts.

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NASA Satellites Unlock Secret to Northern India’s Vanishing Water

08.12.09

 

NASA Hydrologist Matt Rodell discusses vanishing groundwater in India. Credit:NASA
› Watch Video

http://www.nasa.gov/multimedia/nasatv/index.html

 

soil moisture belt

soil moisture belt

 

Groundwater resides beneath the soil surface in permeable rock, clay and sand as illustrated in this conceptual image. Many aquifers extend hundreds of feet underground and in some instances have filled with water over the course of thousands of years. Credit: NASA
http://www.nasa.gov/images/content/378067main_water_table%20illus_226.jpg

groundwater withdrawals as a percentage of groundwater recharge

groundwater withdrawals as a percentage of groundwater recharge

 

 

The map, showing groundwater withdrawals as a percentage of groundwater recharge, is based on state-level estimates of annual withdrawals and recharge reported by India’s Ministry of Water Resources. The three states included in this study are labeled. Credit:NASA/Matt Rodell

http://www.nasa.gov/images/content/378381main_MattRodell_vid_226.jpg

The averaging function (spatial weighting) used to estimate terrestrial water storage changes from GRACE data is mapped. Warmer colors indicate greater sensitivity to terrestrial water storage changes. Credit: NASA/Matt Rodell

http://www.nasa.gov/images/content/378067main_water_table%20illus_226.jpg

Beneath northern India’s irrigated fields of wheat, rice, and barley … beneath its densely populated cities of Jaiphur and New Delhi, the groundwater has been disappearing. Halfway around the world, hydrologists, including Matt Rodell of NASA, have been hunting for it.

Where is northern India’s underground water supply going? According to Rodell and colleagues, it is being pumped and consumed by human activities — principally to irrigate cropland — faster than the aquifers can be replenished by natural processes. They based their conclusions — published in the August 20 issue of Nature — on observations from NASA’s Gravity Recovery and Climate Experiment (GRACE).

“If measures are not taken to ensure sustainable groundwater usage, consequences for the 114 million residents of the region may include a collapse of agricultural output and severe shortages of potable water,” said Rodell, who is based at NASA’s Goddard Space Flight Center in Greenbelt, Md.

 

https://www.quora.com/Why-are-there-no-earthquakes-or-volcanos-in-the-Himalayas

The Himalayas are representative of a modern and active mountain-building event, called anorogeny in geologic parlance. Both the Himalayas and the Cascade Range are the result of plate-to-plate collision in the Theory of Plate Tectonics.
The difference between the Himalayas and the Cascade Range volcanoes is based on density of the lithospheric plates. Yes. The Cascade Range is caused by subduction of more dense ocean crust into and underneath lighter, lower density continental crust. As the oceanic plate dives deeper and deeper, the ocean crust warms, melts, and rises upward through the overriding continental crust “inland” from the plate collision boundary. As that molten rock punches through the continental crust, a curvilinear series of volcanoes, generally parallel to the plate collision boundary, begins to form.

Cascade Range Subduction

Cascade Range Subduction

 

Cascade Range Subduction from J. Wiley & Sons – 2010
In the case of the Cascade Range, the name of this type of volcanic formation is unique in process, as well as geochemistry, and has been referred to as an Andesitic-type after the Andes Mountains. Regardless, the Cascade Range is comprised of intermediate igneous rocks, with a fairly high silica content. High silica makes for high siliceous acid. That creates “sticky” igneous extrusions that often have quite dramatic eruptions [May 1980 Mt. St. Helens eruption].

 

Igneous Rock Classification

Igneous Rock Classification

Igneous Rock Classification Chart – Public Domain

The Himalayas are also a plate-to-plate collision tectonic boundary. In this case, the Indian Plate [of the Indian Subcontinent] is colliding head-on with the Eurasian Plate. Both plates are comprised of continental lithospheric crust, so there is no appreciable distinction in density. Both have a density of approximately 2.7 g/cm³. This as opposed to ocean crust with a mean density of 3.3 g/cm³. The plates try to compete in the plate-to-plate collision but the equal densities of the two plates cannot push one under the other very deep like that in a subduction zone.  The result is large-scale thickening of the continental crust in the region at and surrounding the collision boundary. Other processes occurring in the Himalayas region associated with the orogeny are metamorphism, thrust [compression] faulting, and plateau uplift.

Depiction of Himalayan Collision

Depiction of Himalayan Collision

Generalized Depiction of Himalayan Collision from FHSU – 2010
A perfect analogy is two trucks of the same make and model colliding head-on. The Himalayan Orogeny is the oft mentioned “crumple zone”. Metal does not deform in a brittle sense like competent rock does, so don’t confuse that too much.

With all that being said, there are tremendous temperatures attained at a continental plate-to-plate collision boundary. However, the crust is simply too thick, and too “squashed together” to allow anything to squeeze up and break through to the surface as volcanic eruptions.
References:

FHSU,  2010.  Image of Himalayan Collision.  Fort Hays State University.  Hays, Kansas.  2010.
Wiley & Sons, J.,  2010.  Image of Cascade Range Subduction Zone.  J. Wiley & Sons.  Hoboken, New Jersey.  2010.

 

Mt. Everest was formed (is forming) by two tectonic plates colliding–the Indo-Australian Plate and the Eurasian plate.

Sometimes, when two tectonic plates collide, volcanoes form (such as the Juan de Fuca plate and the North American Plate forming the Cascades). However, this has to do with one plate–in this case the Juan de Fuca Plate sliding or subducting beneath another–the North American Plate. This happens because the oceanic plate (the Juan de Fuca Plate) is more dense than than the continental plate (the NA Plate). For reasons I won’t get into here, magma forms between the two plates as one subducts beneath the other and volcanoes are formed.

Mt. Everest is formed by two continental plates colliding. Continental plates are generally too buoyant to subduct beneath each other. While some subduction occurred during this collision, most of what happened was crustal shortening. Think about what happens when you have a rug on a wood floor and push two ends toward each other. It buckles and folds up in itself. This is a simplified version of what happened in the Himalaya.

Because little to no subduction is occurring, no magma is forming and Mt. Everest will not become a volcano.

The Himalayas were created by two continental plates colliding. What happens when two masses of rocks with some similarities, like in density, collide? Both of them rise. There is a lot of heat produced. However, there isn’t enough heat to melt rocks completely. For there to be a volcano, there has to be a source of molten rock.

This material can occur if the two masses of rocks have vastly different densities. In this case, the heavier mass will slide above the other. The mass on the bottom will melt. This molten rock material will rise and create a volcano. or two or more. This, however can not happen in the HImalayas. The two masses in action are the Indian Plate and the Eurasian Plate, which have similar rock density.

 

Volcanic Eruptions and the Role of Sulfur Dioxide in Climate Change

In March and April of this year, a series of severe volcanic eruptions shook Alaska’s Mount Redoubt.1  To date, the largest of the eruptions produced an ash plume that reached 50,000 feet above sea level and released a significant amount of sulfur dioxide (CAS Registry Number® 7446-09-5) into the earth’s atmosphere.  According to the Alaska Volcano Observatory, “The main concerns for human health in volcanic haze consist of ash, sulfur dioxide gas (SO2), and sulfuric acid droplets (H2SO4), which forms when volcanic SO2 oxidizes in the atmosphere.”1

While there is obvious reason for alarm among local populations, sulfur dioxide from the Mount Redoubt eruption could also have more widespread impacts, particularly on the climate.  According to a 1997 article published in the Journal of Geology, “The mechanism by which large eruptions affect climate is generally accepted: injection of sulfur into the stratosphere and conversion to sulfate aerosol, which in turn reduces the solar energy reaching the earth’s surface.”2

In the years following a volcanic eruption, sulfate aerosol that remains in the atmosphere is thought to cause surface cooling by reflecting the sun’s energy back into space.  In fact, sulfate aerosol from the massive eruption of Indonesia’s Mount Tambora in 1815 is blamed, at least in part, for the “year without a summer” reported in Europe and North America in 1816:

  • “Daily temperatures (especially the daily minimums) were in many cases abnormally low from late spring through early fall; frequent northwest winds brought snow and frost to northern New England and Canada, and heavy rains fell in western Europe.  Many crops failed to ripen, and the poor harvests led to famine, disease, and social distress…”3

Supporting this claim, sulfate aerosol-related climate changes were also reported after the 1991 eruption of Mount Pinatubo in the Philippines.4  An article published inScience in 2002 summarizes a decade’s worth of research on Pinatubo’s effects on the global climate, highlighting impacts far more widespread and complex than previously thought:

You can use SciFinder® or STN® to search the CAS databases for additional information about sulfur dioxide from volcanic eruptions.  If your organization is enabled to use the web version of SciFinder, you can click the links in this article to directly access details of the substances and references.

 

Volcanic ash vs sulfur aerosols

The primary role of volcanic sulfur aerosols in causing short-term changes in the world’s climate following some eruptions, instead of volcanic ash, was hypothesized by scientists in the early 1980’s. They based their hypothesis on the effects of several explosive eruptions in Indonesia and the world’s largest historical effusive eruption in Iceland.

Scientists studied three historical explosive eruptions of different sizes in Indonesia–Tambora (1815), Krakatau (1883), and Agung (1963). They noted that decreases in surface temperatures after the eruptions were of similar magnitude (0.18-1.3 °C). The amount of material injected into the stratosphere, however, differed greatly. By comparing the estimated amount of ash vs. sulfur injected into the stratosphere by each eruption, it was suggested that the longer residence time of sulfate aerosols, not the ash particles which fall out within a few months of an eruption, was the paramount controlling factor (Rampino and Self, 1982).

In contrast to these explosive eruptions, one of the most severe volcano-related climate effects in historical times was associated with a largely nonexplosive eruption that produced very little ash–the 1783 eruption of Laki crater-row in Iceland. The eruption lasted 8-9 months and extruded about 12.3 km3 of basaltic lava over an area of 565 km2. A bluish haze of sulfur aerosols all over Iceland destroyed most summer crops in the country; the crop failure led to the loss of 75% of all livestock and the deaths of 24% of the population (H. Sigurdsson, 1982). The bluish haze drifted east across Europe during the 1783-1784 winter, which was unusually severe.

Clearly, these examples suggested that the explosivity of an eruption and the amount of ash injected into the stratosphere are not the main factors in causing a change in Earth’s climate. Instead, scientists concluded that it must be the amount of sulfur in the erupting magma.

The eruption of El Chichon, Mexico, in 1982 conclusively demonstrated this idea was correct. The explosive eruption injected at least 8 Mt of sulfur aerosols into the atmosphere, and it was followed by a measureable cooling of parts of the Earth’s surface and a warming of the upper atmosphere. A similar-sized eruption at Mount St. Helens in 1980, however, injected only about 1 Mt of sulfur aerosols into the stratosphere. The eruption of Mount St. Helens injected much less sulfur into the atmosphere–it did not result in a noticeable cooling of the Earth’s surface. The newly launched TOMS satellite (in 1978) made it possible to measure these differences in the eruption clouds. Such direct measurements of the eruption clouds combined with surface temperatures make it possible to study the corrleation between volcanic sulfur aerosols (instead of ash) and temporary changes in the world’s climate after some volcanic eruptions.

 

Hazards Of Volcanic Ash

A multitude of dangerous particals and gases, such as aerosols, are carried in volcanic ash. Some of these include;

  • Carbon dioxide
  • Sulfates (sulfur dioxide)
  • Hydrochloric acid
  • Hydroflouric acid

These each have different but serious effects on human health if exposed, which will be discussed later.

In addition, volcanic ash can cause reduced visibility, and it is recommended that precautions are taken when driving.

Sources: Where Does It Come From?

Figure 1

volcanoes found all over the Earth, particularly at plate boundaries

volcanoes found all over the Earth, particularly at plate boundaries

There are volcanoes found all over the Earth, particularly at plate boundaries (see figure 1). This is due to the collision of plates, which causes uplift in the overlying crust. This uplift results in the formation of mountainous landforms; melting of the crust due to frictional heating is what creates magma, which can erupt out of these mountains when pressure gets too high.

Some of the most notable volcanic eruptions are:

  • the 1783 eruption of Mt. Laki in Iceland
    • released clouds of poisonous flourine and sulfur dioxide which killed off about 50% of the livestock population
    • that summer in Great Britain was known as “sand-summer” due to ash carried over the Atlantic
    • poisonous clouds spread over Europe, and a buildup of aerosols caused a cooling effect in the entire Northern Hemisphere
  • the 1815 eruption of Mt. Tambora in Indonesia
    • gas releases caused the Stratosphere to change drastically
    • noxious ash and poisoned rain clouds killed off vegetation
  • the 1902 eruption of Mt. Pelee in Martinique
    • spewed toxic clouds traveling at speeds of 600mph
    • largest eruption in the 20th century

For further information on volcanoes around the world, visit http://www.mapsofworld.com/major-volcanoes.htm.

http://www.chm.bris.ac.uk/webprojects2003/silvester/Page6Famous.htm

 

  • EEA-33 emissions of sulphur oxides (SOX) have decreased by 74% between 1990 and 2011. In 2011, the most significant sectoral source of SOX emissions was ‘Energy production and distribution’ (58% of total emissions), followed by emissions occurring from ‘Energy use in industry’ (20%) and in the ‘Commercial, institutional and households’ (15%) sector.
  • The reduction in emissions since 1990 has been achieved as a result of a combination of measures, including fuel-switching in energy-related sectors away from high-sulphur solid and liquid fuels to low-sulphur fuels such as natural gas, the fitting of flue gas desulphurisation abatement technology in industrial facilities and the impact of European Union directives relating to the sulphur content of certain liquid fuels.
  • All of the EU-28 Member States have reduced their national SOX emissions below the level of the 2010 emission ceilings set in the National Emission Ceilings Directive (NECD)[1]. Emissions in 2011 for the three EEA countries having emission ceilings set under the UNECE/CLRTAP Gothenburg protocol (Liechtenstein, Norway and Switzerland) were also below the level of their respective 2010 ceilings.
  • Environmental context: Typically, sulphur dioxide is emitted when fuels or other materials containing sulphur are combusted or oxidised. It is a pollutant that contributes to acid deposition, which, in turn, can lead to changes in soil and water quality. The subsequent impacts of acid deposition can be significant, including adverse effects on aquatic ecosystems in rivers and lakes and damage to forests, crops and other vegetation. SO2 emissions also aggravate asthma conditions and can reduce lung function and inflame the respiratory tract. They also contribute, as a secondary particulate pollutant, to the formation of particulate matter in the atmosphere, an important air pollutant in terms of its adverse impact on human health. Furthermore, the formation of sulphate particles in the atmosphere following the release of SO2 results in reflection of solar radiation, which leads to net cooling of the atmosphere.
faults  sn-seafloor

faults sn-seafloor

 

Glacier - Helheim

Glacier – Helheim

 

Making North America

Making North America

 

so2-global-1986

so2-global-1986

 

What caused the Nepal earthquake

What caused the Nepal earthquake

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