Scientists predicts more fires
in a warmer, future world


A warmer planet is helping to fuel more wildfires in the United States, according to a new study.

Environmental scientists at Harvard University predict that by 2050, wildfire seasons will be three weeks longer, up to twice as smoky, and will burn a wider area in the western part of the country.   
   
Fires in the Western United States have gotten worse since the 1970s. Scientists at Harvard University School of Engineering and Applied Sciences looked at past weather conditions and wildfires to find out why.
 
“In some regions, like the Rocky Mountains, really temperature is the driving force, but elsewhere variables like relative humidity can play a role," said Loretta Mickley, an atmospheric chemist and co-author of the study. "If one year is particularly moist, for example, in the Great Basin, Nevada, Utah area, then that will foster a lot of vegetation growth and then the following year all that vegetation can feed wildfires and their spread.”

The scientists then turned to a suite of 15 climate models based on the conclusions of the Intergovernmental Panel on Climate Change, the leading international body for the assessment of global warming. On average, the models predicted increases between 2 and 2.5 degrees Celsius by 2050.

“The finding for rainfall, which can diminish fire activity, and for relative humidity, we found only small changes, with some models predicting small increases and some models predicting small decreases in those variables," Ms. Mickley said. "So we found as in the past, temperature is really driving the changes that we predict for the future.” 

The calculations suggest the probability of large wildfires would increase by factors of two or three, and that by 2050, the more than four-month fire season would be three weeks longer. 

“If we just look at one month in the future for example, the area burned in the very forested Rockies could quadruple," Mickley said. "If we look at the whole fire season, we see increases more on the order of say 20 or 30 percent to 100 percent.”

While air quality in the United States has greatly improved in recent decades in response to federal laws, Ms. Mickley says air pollution is an unexpected consequence of longer lasting, widespread wildfires.    

“These increases in wildfires could totally disrupt our efforts to clean the air," she said. "Last weekend, there was an area the size of some states in the eastern U.S. blanketed with unhealthy air over California and Nevada. And we call this increase in smoke an important climate penalty on air quality.” 

That penalty would be air that is twice as smoky as it is today.  These findings, Ms. Mickley says, underscore the need for better forest management.  But also she adds, they send a signal to policy makers and the public to reduce fossil fuel emissions that are warming the planet.


2016 Mars landing locations
narrowed to four by NASA
 

The U.S. space agency, NASA, has narrowed down to four locations  the potential landing sites for a 2016 mission to Mars.

Twenty-two sites were originally considered for the mission, which the scientists are calling the Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport  lander, InSight for short. It is scheduled to launch in March 2016 and land on Mars six months later.

Scientists will focus two of NASA's Mars Reconnaissance Orbiter cameras on the chosen four sites in the coming months to make a final decision between them. All four spots lie near each other on an equatorial plane in an area of Mars called Elysium Planitia.

NASA hopes the InSight lander will provide information on how Mars was formed, which also could provide a better understanding of how the rocky planets of the Solar System, including Earth, formed.

Unlike other missions, the main factor in determining the 2016 landing site is safety, meaning the sites should have a smooth terrain, few rocks and very little slope.

"This mission's science goals are not related to any specific location on Mars because we're studying the planet as a whole, down to its core," said Bruce Banerdt, InSight’s principal investigator at Jet Propulsion Laboratory in a statement. "Mission safety and survival are what drive our criteria for a landing site."

Each of the four sites is an ellipse measuring 130 kilometers from east to west and 27 kilometers from north to south. NASA says the InSight will have a 99 percent chance of landing within the chosen ellipse.

Elysium Planitia meets the requirements for InSight because it is close to the equator, so that the spacecraft’s solar array will be able to provide power all year. Also the areas are all low enough to allow the landing craft to decelerate more completely before landing.

The only other two areas of Mars meeting the requirements of being near the equator at low elevation, Isidis Planitia and Valles Marineris, were said to be too rocky and windy. Valles Marineris also lacks any swath of flat ground large enough for a safe landing.

Another requirement is that InSight needs to land on ground that allows the lander to deploy a heat-flow probe that will hammer itself several meters into the Martian surface to monitor heat coming from the planet’s interior.

In order to ensure there no hard rocks that might block the probe, scientists studied Mars Reconnaissance Orbiter images of large rocks near Martian craters formed by asteroid impacts. Impacts excavate rocks from the subsurface, so by looking in the area surrounding craters, the scientists can tell if the subsurface would have probe-blocking rocks lurking beneath the soil surface.


Charity and emergency rooms
handling more U.S. dental care


Emily Bratcher, 4, is having a cavity filled.

And as uncomfortable as getting a tooth drilled might be, she’s lucky to be sitting in Rhonda Switzer's dentist chair at all.

Last year, the U.S. Centers for Disease Control and Prevention ranked Tennessee 47th among the 50 states for dental care. The Centers said the number of Tennessee residents visiting a dentist routinely is on the decline.

Working but poor families like Emily’s have the hardest time accessing dental care. They make too much money to qualify for government aid but too little to pay for the care at market rates.

So Emily and her sister are being treated at the Interfaith Dental Clinic, a medical charity operated by a faith-based ministry. It can be especially important for people struggling to find or keep a job to have good oral health.

“Unfortunately, our society looks at people’s weight, their dialect, and their teeth in making decisions like, is that person educated or employable,” said Ms. Switzer, the executive director.

And just as unfortunately, the problem is only getting worse. The Pew Research Center released a study earlier this year that indicates the U.S. has a severe shortage of dentists.

More than half of those currently in practice are nearing retirement. Even more alarming, a growing number of Americans are showing up at hospital emergency rooms looking for dental care.

“This is the canary in the coal mine. This is the symptom that tells you we have a broken dental delivery system,” said Shelly Gehshan, director of the Pew Children’s Dental Campaign. “We don’t have enough dentists. We don’t have enough clinics. We don’t have enough dental insurance. We don’t have enough financing in the system. We don’t have enough prevention. It’s a neglected area.”

Ms. Gehshan says the Affordable Care Act, President Barack Obama’s signature healthcare reform initiative, will, in theory, extend dental coverage to every child in the nation, but she says the poorest of those children may still have trouble accessing care.

“They need help with transportation, or translation, or child care, and most dental care is provided by private dentists and they’re not set up to provide those extra services,” she said.

Ms. Gehshan says non-profit clinics like Ms. Switzer’s facility are better equipped to address those needs, but charitable operations are rare. She says one possible solution some states are exploring is introducing what she calls mid-level dental practitioners. Currently, only fully accredited doctors are allowed to practice dentistry in the U.S.

“In other countries there are other more different types of providers. So they have dental hygienists with extra training, or dental therapists, or people with both types of training," Ms. Gehshan said.

Little Emily Bratcher’s mother, Deborah, is not really interested in the politics of health care. She just wants her daughters to see a dentist regularly, and she’s a little angry it is not happening now.

“It’s just upsetting, because I don’t want my children to go through life having bad teeth, because I can’t afford $3,000 for dental work every other month or something,” Ms. Bratcher said.

The Pew Center’s Ms. Gehshan notes that the Affordable Care Act does not mandate dental coverage for adults, meaning millions of Americans will continue to struggle to maintain good oral health.


Out of Africa theory seems
to be accurate for TB, too


The origins of humans have been traced to Africa. And now, so have the origins of tuberculosis. New research shows the evolutionary trees of both humans and TB have grown side-by-side.

TB bacteria originated in Africa at least 70,000 years ago. That’s the finding of a team of researchers led by Sebastien Gagneaux of the Swiss Tropical and Public Health Institute. But why study the history of TB?

“At the end of the day, it’s a certain kind of historic question and there have been long discussions about where TB came from originally," Gagneaux said,. "That’s on the one hand. On the other hand, the idea is that by learning from the past and how infectious disease evolves over time, this potentially could give us some clue about the future of the TB epidemic.”

To trace the origins of TB researchers relied on genetic material, which is relatively easy to come by.

“The trick is to use the genomic information that we can get from bacteria living today. That’s an approach which has been used for all kinds of other organisms, including humans, themselves. So we actually are learning a lot from what people are doing with human genetics,” he said.

Gagneaux said that the evolutionary trees of humans and TB probably did more than just grow side by side.

“I think that’s a nice way to put it. Maybe you can even say one inside the other. Imagine where the TB bacteria live, which is actually inside of human bodies. Yes, side by side, or one inside the other.”

Humans have bacteria on them and in them all the time. In fact, they help keep them alive. Researchers are trying to determine if tuberculosis bacteria were always harmful to humans.

“That’s also something that we’re trying to address in this work because there’s this striking feature in tuberculosis, which is this phenomena called latency – so-called latent infection -- meaning that people can carry these bacteria. So they’re actually infected without having any symptoms of disease. This latency period can last for several decades. Most of the people, who are actually carrying these bacteria, will actually never develop so-called active tuberculosis,” he said.

Studies are trying to determine why only 5 to 10 percent of the estimated two billion people infected with the bacteria actually come down with active tuberculosis.

Another question is whether the bacteria were at one time beneficial to humans?

“Obviously, there seems to be something special about these five to ten percent of people who are coming down. Maybe that’s just bad luck. We know there are obvious very strong risk factors, such as HIV co-infection or malnutrition. Diabetes is also a factor, which can increase your risk of developing active tuberculosis once you have been infected. But again this idea that maybe carrying these bacteria in this latent form could potentially be beneficial because it might protect against other diseases. Again, that’s a very provocative hypothesis, which we, however, cannot completely neglect.”

Gagneaux said TB left Africa when humans did, about 65,000 to 70,000 years ago. Then, about 10,000 years ago, came the Neolithic Demographic Transition. It’s the time when people started to develop agriculture and domesticate animals. But it was also a time when diseases jumped from domesticated animals to humans for the first time. Gagneaux says for many years it was assumed that TB took the same path – from animals to humans. However, the research shows that TB in humans pre-dates the domestication of animals. It’s particularly adapted to live inside humans and can’t really survive on its own in the environment.

There was another important development during the Neolithic Demographic Transition. Humans started to form settlements that were densely populated. It’s an ideal situation for the spread of tuberculosis through the air from human to human.

“Because of these changes in these human behaviors and numbers, potentially TB might have become more virulent in the sense of causing disease maybe more quickly or maybe a more deadly disease. It’s true that TB is very deadly nowadays. So if you don’t treat it, it kills up to 50 percent of people who actually have active tuberculosis,” Gagneaux said.

He added that before settlements, in the hunter-gatherer days, perhaps TB was not as deadly.

“Overly deadly would be a bad strategy for any pathogen because you might just kill off all susceptible hosts and you might end up with nobody else to infect. And so only once through this Neolithic transition -- when more and more people were actually living close by -- TB maybe evolved in a way to be able to become more virulent and take advantage, if you will, of this increasing number of susceptible people to infect.”

After humans left Africa, they started to change in appearance as they adapted to their new geographical locations. TB also evolved and now there are many different strains of bacteria that cause the disease. The strain found in South Africa differs from that found in China, for example. Africa, though, still has the greatest diversity of TB strains.

Researchers hope that knowing the evolutionary history of TB will help in the development of new drug treatments and vaccines. Currently, the number of drug-resistant TB cases is growing. The knowledge may also help predict future patterns of the disease.


Obama orders vet benefits
for same-sex married couples


U.S. President Barack Obama has ordered veterans' benefits extended to same-sex married couples.

U.S. Attorney General Eric Holder wrote in a letter to Congress that the provision of veterans' benefits laws that defines marriage as between a man and a woman will cease.

Holder wrote that the Supreme Court's decision declaring the Defense of Marriage Act unconstitutional also should have applied to veterans' benefits, even if the court did not directly address that issue.

The federal Defense of Marriage Act defined marriage as being between a man and woman. The high court overturned the law in June.