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Mystery of arsenic release into groundwater solved

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New York: Stanford scientists have solved an important mystery about where the microbes responsible for releasing dangerous arsenic into groundwater in Southeast Asia get their food.

Groundwater in many countries, including India, China, Bangladesh, Myanmar and Vietnam, contains concentrations of arsenic 20 to 100 times greater than the World Health Organisation’s (WHO) recommended limit.

Arsenic is bound to iron oxide compounds in rocks from the Himalayas and gets washed down the major rivers and deposited in the lowland basins and deltas.

Scientists know that in the absence of oxygen, some bacteria living in those deposited sediments can use arsenic and iron oxide particles as an alternative means of respiration.

When they do this, however, the microbes separate the arsenic and iron oxides and transfer the toxin into underlying groundwater.

The mystery in this system, though, is an obvious source of energy that the microbes can tap to fuel the separation process.

“The question that really limits our ability to come up with predictive models of groundwater arsenic concentrations is how and why does the food they use vary across the landscape and with sediment depth,” said professor Scott Fendorf from Stanford.

In their study, Fendorf and his team found that mixing sediments collected from different depths in vials with artificial groundwater revealed that the oxygen-deprived bacteria living in the upper few feet of permanent wetlands were releasing arsenic.

However, water mixed with sediments gathered from the same shallow layers of seasonal wetlands was arsenic free.

The Stanford scientists hypothesized that bacteria residing in the shallow layers of seasonal wetlands were eating all of the digestible plant material during dry periods when sediments are exposed to air and the microbes have access to oxygen.

As a result, no food is left for the microbes when the floods returned, rendering them unable to cleave arsenic particles from iron oxides.

“The arsenic-releasing bacteria living in the shallow regions of seasonal wetlands are ‘reactive’ carbon limited – that is, they don’t release arsenic into the water because there isn’t enough carbon available in a form they can use,” Fendorf explained.

The findings have large-scale implications for projecting changes in arsenic concentrations with land development in South and Southeast Asia and for the terrestrial carbon cycle.

“If you change the hydrology of a region by building dams or levies that change the course of the water, or if you change agricultural practices and introduce oxygen or nitrate into sediments where they didn’t exist before, that will alter the release of arsenic,” Fendorf said.

The findings were published in the journal Nature Geosciences.

(IANS)

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Experts Say Measles Victims Dropped Below 100,000 in 2016

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Measles Victims Dropped
Foriza Begum, background, a newly arrived Rohingya Muslim from Myanmar, reacts to her daughter Nosmin Fatima's scream as she receives a vaccination to prevent measles and rubella at a makeshift medical center in Teknaf, Bangladesh. VOA
  • Latest reports of WHO, UNICEF, and the U.S. Centers for Disease Control and Prevention say the rate of deaths from measles has dropped.
  • As per experts, a number of people who died from measles in 2016 were about 90,000, compared to 550,000 in 2000.

The World Health Organization, UNICEF, and the U.S. Centers for Disease Control and Prevention say the rate of deaths from measles has dropped 84 percent since the beginning of a global vaccination campaign in 2000.

Experts say the number of people who died from the disease in 2016 was about 90,000, compared to more than 550,000 deaths in 2000. This marks the first time that worldwide measles deaths have fallen to less than 100,000 per year.

Robert Linkins, of the Measles and Rubella Initiative at the CDC, said in a statement that “saving an average of 1.3 million lives per year through vaccine is an incredible achievement and makes a world free of measles seem possible, even probable, in our lifetime.”

Since 2000, some 5.5 billion doses of measles vaccine have been administered to children through routine immunization services and mass vaccination campaigns. The disease is contagious through air particles and can spread quickly. The disease kills more people every year than any other vaccine-preventable disease.

But the WHO says the world is still far from reaching regional measles elimination goals. Since 2009, officials have managed to deliver a first dose of the vaccine to 85 percent of the babies who need it, but there has been no improvement in that rate in eight years. And only 64 percent of the affected population has gotten the second dose, which comes when a child is four or five years old.

The WHO says “far too many children” — about 20.8 million — have not had their first vaccine dose. Most of those children live in Nigeria, India, Pakistan, Indonesia, Ethiopia and the Democratic Republic of Congo.

The disease puts children at risk of developing complications such as pneumonia, diarrhea, encephalitis, and blindness.(VOA)

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PM Modi inaugurates Ferry Service, Calls it his ‘Dream Project’

Calling it his dream project, PM Modi has called the service "a landmark occasion for entire South-East Asia".

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Modi
Prime Minister Narendra Modi. Wikimedia

Gujarat, October 22, 2017 : Prime Minister Narendra Modi inaugurated the first phase of the Ghogha-Dahej Ro-Ro ferry service, a first-of-its-kind project in India, calling it “a landmark occasion for entire South-East Asia”.

Describing it as his dream project, Modi said the ferry service was his “invaluable gift to India” and claimed that the even for South-East Asia, this was the first project of its size.

He said it were his efforts that gave birth to this ferry service which he had heard about only in his school days.

“It seems implementation of all good works are my luck,” Modi joked. “New changes don’t come from cliched attitude but new thinking. We changed the way of thinking,” he said.

He said the service would shorten a 360-km distance to 31 km or a journey of seven hours to one hour. (IANS)

 

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Do You Know Which is the Unhealthiest Country in the World?

Are you living in the most unhealthy country in the world?

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Unhealthiest country in the world
Did you think you were living in one of the world's healthiest country? Think again! VOA

Geneva, September 28, 2017 : Do you know which is the unhealthiest country in the world? If you think it is some region from the African continent, you are mistaken.

According to a new study by Clinic Compare, the Czech Republic has been recognized as the unhealthiest country in the world.

Drawing upon data gathered by the World Health Organization (WHO), CIA World Factbook and the World Lung Association, 179 countries around the world were assessed on three key factors,

  • Alcohol consumption
  • Tobacco consumption
  • Prevalence of obesity

The study thus revealed the most unhealthy country in the world – Czech Republic, and highlighted the need for citizens to change their lifestyle in order to combat life-threatening illnesses and maintain and enjoy a healthy life.

ALSO READ Live Healthy Lifestyle with these Diet Hacks

World’s most unhealthy countries

 

1. Czech Republic
2. Russia
3. Slovenia
4. Belarus
5. Slovakia
6. Hungary
7. Croatia
8. Poland
9. Luxembourg
10. Lithuania and the United States

 

As per the examination, the residents of Czech Republic positioned as the world’s greatest liquor consumers, with every individual expending 13.7 liters of liquor for each annum (around 1.5 shots per day). They additionally ranked eleventh on the list of the highest tobacco customers.

This comes as a surprise as poverty-stricken countries of Africa were instead found to be among the healthiest countries in the world.

According to the research, Eastern Europe emerged as the unhealthiest region in the world, occupying nine out of the best 10 top spots in the list.

41 per cent of the population in Samoa was further revealed to have a BMI over 30, making Oceania the world’s fattest region. Also included in the top 10 list of the fattest regions were Fiji, Tuvalu and Kiribati.

Healthiest Country in the World

The findings revealed that the healthiest country was Afghanistan with merely 2.7 per cent of the population having a BMI over 30. This places the country on the world’s second lowest rate of obesity.

It was further revealed that the citizens of Afghanistan consume the least recorded quantity of alcohol and smoke 83 cigarettes a year. This can be largely attributed to the nation’s laws that forbid the possession and consumption of alcohol.

The research placed Guinea as the second healthiest country, closely followed by Niger and Nepal.

ALSO READ WHO says Millions of People are Dying Pre-mature Deaths Due to Non-Communicable Diseases

World’s healthiest countries

 

1. Afghanistan

2. Guinea

3. Niger

4. Nepal

5. DR Congo

6. Eritrea

7. Malawi

8. Somalia

9. Mozambique

10. Ethiopia

 

Eight Countries from Africa made it to the list of the healthiest countries in the world, which comes as a pleasant surprise for all.

According to a WHO report released in mid-September, it was revealed that non-communicable diseases such as diabetes, cancer and cardio-vascular diseases are an increasing cause of premature deaths all around the world, taking as many as 30 million lives annually.

These diseases cause self-inflicted damage and trace their roots to individual lifestyle choices such as smoking, alcohol consumption, drugs and unhealthy or unbalanced diet.

The new findings put greater pressure on the countries that have made it to the list of unhealthy countries, thereby urging them to undertake stronger measures.