Spleen Size Signals Swimming Skill

Bajau Children Row Boat

The Bajau people, or “Sea Nomads”, of the Southeastern Asian Islands are renowned as the best divers in the world. The Bajau have been occupying houseboats for generations, living an entirely marine existence as deep-water hunter-gatherers. They spend hours each day underwater, reaching depths of over 200 feet, equipped with no more than weights and wooden goggles. Numerous studies from Tibet looking at physiology and genetics of high altitude societies have raised the question, how are the best divers in the world adapted to their niche?

A recent study compared the Bajau to the neighboring land-dwelling Salaun people, by analyzing DNA, and spleen size. The human body is well adapted to diving; upon breath holding and the sensation of cold water on the face, the body will change its behavior to limit oxygen consumption and contract the spleen to release oxygenated red blood cells into the circulatory system. The Bajau people’s seemingly superhuman diving skills may be explained by physiological differences, like larger spleens.

Researchers took measurements of non–related Bajau (to avoid familial similarities) using ultrasounds and saliva samples to analyze spleen size and DNA, respectively. As a means of comparison, the scientists took similar measurements from the Salaun people of the same area, who have been identified through DNA to be amongst the most genetically similar to the Bajau, but live a grounded existence with little interaction to the marine environment.

The results show that the Bajau people did have significantly larger spleens than the Salaun people and DNA analysis confidently informed a specific gene related to spleen size and thyroid hormones that was expressed at significantly greater levels in Bajau than Salaun people. This is the physiological and genetic difference the researchers were looking for.

So does that mean professional divers have larger spleens than people who can’t swim? Not necessarily. These differences are the result of natural selection. For thousands of years the Bajau have occupied houseboats, traversing the seas of Southeast Asia, living off of materials and food gathered from deep sea floors, using only simple tools. Over so many years, generations, and deep-water dives, these people have evolved. The environment changed their bodies and their genetics to make them better divers. Imagine how your ancestor’s lives adapted you.



Ilardo MA, Moltke I, Korneliussen TS, Cheng J, Stern AJ, et al., (2018) Physiological and Genetic Adaptations to Diving in Sea Nomads. DOI: 10.1016/j.cell.2018.03.054

The Deep Space Gateway Just Keeps Getting Better!

Picture of the Perseid Meteor Shower of 2015.

More Deep Space Gateway! What were you expecting? In February 2018, Researchers at NASA from the NASA Johnson Space Center have started thinking about even more applications of the Deep Space Gateway. The next proposed addition is to characterize comets and asteroids though the collection of cosmic dust in the space between the Earth and the Moon (cislunar). Every year the earth moves through debris streams of dust and small particles from comets and asteroids crossing into Earth’s orbit. These debris areas create what we commonly call meteor showers. By using a device installed on the DSG, we could figure out the composition of a dozen or more comets and asteroids without leaving the space around our moon. The Deep Space Gateway is a perfect fit for this experiment because cosmic dust samples are not very large, and its permanent orbit allows for long collection periods. The current working name for the device is the Dust Analyzer.

The team gave both a science description and instrument operation for the device. Using the Dust Analyzer, the researchers will be able to analyze the elemental and potentially isotopic composition of comets and asteroids. Since we can already identify the parent object of many areas of cosmic dust, measuring the composition of these areas will give us detailed information about a large number of the asteroids in cislunar space. The researchers said that the experiment will give light to two things. The first is that the data will help provide information on the origins of never before researched asteroids. Also, the results will increase the scientific value of NASA’s Cosmic Dust collection by mapping its contents to individual comets and asteroids. Even the experimental process used by the Dust Analyzer is cool! The Analyzer would create dust debris that hits it at high velocity and that dust would be converted into ionized gas for analysis! There’s a lot of fascinating ideas coming from the Deep Space Gateway, so I can’t wait to see which ideas are presented next and what actually gets implemented!


Link: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180002181.pdf


Fries, M., Fisher, K. 2018. Direct Characterization of Comets and Asteroids via Cosmic Dust Analysis from the Deep Space Gateway. NASA Technical Reports Server. 20180002181.

Is It Cancer? Check Your Ink

Mouse tattoos
Calcium detecting tattoos in mice

In recent years increased research has been done on the medical applications of tattoos, they have proven effective in delivering drugs, administering vaccines, and working as blood sugar level sensors in conjunction with skin based electronics. New research out of Switzerland, published in Science, has essentially invented a tattoo that can detect cancer. The tattoo “ink” is injected under the skin, and only becomes visible when it detects elevated calcium levels in the blood, an indicator of breast cancer, colon cancer, lung cancer, and more.


The procedure was developed and demonstrated in mice using reprogrammed calcium detecting cells to produce melanin, a black pigment which color moles and freckles. Thus the tattoo would be invisible when administered, but would appear as a large black dot if blood calcium levels became consistently elevated, as in many types of cancer. Perhaps the greatest difficulty in cancer treatment is diagnosis; by the time a patient notices symptoms and seeks medical attention, the disease may have already begun to grow aggressively. By administering these dormant monitors in people, particularly those at a high risk, cancer can be detected as soon as physiological changes begin.


The tattoo ink is actually made from calcium detecting cells that humans use to regulate calcium in the blood. Calcium is an essential compound for maintaining functions like cell growth, cell death, cell movement and more. But its concentration is precisely regulated, if there is too little the bone marrow will produce more, if there is too much, the bones will stop producing it. So when calcium does become elevated it is usually corrected in a few minutes. But certain cancers can inhibit the hormone that acts to regulate calcium production, and so calcium levels remain consistently elevated.


Though there are other pathologies that can cause elevated calcium levels, the tattoo worked well in mice to detect certain cancers before they became symptomatic. It has also been shown to be resilient to short term fluctuations in blood calcium levels and would be especially useful for patients who display risk factors for these cancers such as those with a diagnosed parent, a history of smoking, or work in hazardous environments.


But even if it is best used in niche applications, this represents a dramatic shift towards an entirely new field of diagnostic tests. Human beings can already have their DNA analyzed and identified for specific disease risk factors, if similar tattoos can be created for Celiac Disease, Parkinsons, Alzheimers, and the rest, then medical attention can be sought and treatment strategies implemented when the disease has only just taken hold, when it is at its most treatable.


Tastanova A, Folcher M, Müller M, Camenisch G, Ponti A, et al., (2018) Synthetic biology-based cellular biomedical tattoo for detection of hypercalcemia associated with cancer. DOI: 10.1126/scitranslmed.aap8562

The Swamp Monster That Could Save Us All

Swampland in West Milford, New Jersey.
Source: Flickr

Image a creature that could break down environmental toxin, cleaning our water better than we ever have done before. A research team at Princeton reported their discovery of exactly that – a bacteria that provides a more efficient method for treating toxins found in swage, fertilizer runoff, and other forms of water pollution on April 11, 2018 in PLOS ONE journal. The bacteria, Acidimicrobiaceae bacterium A6, can break down ammonium anaerobically, or without oxygen. This is a hug breakthrough as an alternative method to the costly oxygen-dependent methods currently used in sewage treatment.

Waste water treatment plants benefit heavily from this discovery, as many of them discharge into watersheds and must remove ammonium beforehand. Doing so has always requires churning copious amounts of oxygen into the waste to feed the bacteria that carries out the process. Most bacterium use oxygen in a chemical reaction that turns ammonium into nitrite, which is then converted into benign nitrogen gas by another type of bacteria.

Before conducting their experiment, the authors of the study hypothesized that A6 performs the Feammox reaction instead, a chemical reaction that breaks down ammonium, taking place in wetland environments such as the riparian wetlands and New Jersey. Scientist previously were unsure of what enabled this reaction to occur, but after conducting a study in 2015, they found that the Feammox reaction only took place in swamp samples where Actinobacteria were present.

In the study most recently published by the researchers at Princeton, mixtures of soil samples and metal mediums were placed in an oxygen-free environment to mimic wetland soil where the bacteria originated. After checking samples every two weeks over a year, the scientists discovered a sample of soil where ammonium degradation took place. They identified that A6 was the bacteria carrying out the Feammox reaction through genetic sequencing.

Researchers emphasized the potential to treat other environmental pollutants found in oxygen-poor areas, such as underground aquifers. A6’s ability to remove environmental toxins from waste opens up the doors for ensuring clean water in a variety of situations, from sewage treatment to cleaning up contaminated wells.

The research team hopes to explore how to build a reactor where the A6 bacteria can be used on an industrial scale to process ammonium. In fact, they are in the works of building a prototype reactor with the Chinese environmental ministry. Besides oxidizing ammonium, A6 can also remove two common pollutants that are hard to treat called trichloroethylene and tetrachloroethylene.

This discovery has the potential to address a range of environmental problems as ammonium has dire effects on the environment if not removed for water sources. Once in waterways, ammonium can cause of a depletion of oxygen as well as eutrophication, an excessive growth of algae. Both have detrimental effects to watershed ecosystems, from streams to rivers to oceans. Taking advantage of bacteria A6 could save not only ecosystems and environmental health, but protect human health as well.


Shan Huang, Peter R. Jaff�. Isolation and characterization of an ammonium-oxidizing iron reducer: Acidimicrobiaceae sp. A6PLOS ONE, 2018; 13 (4): e0194007 DOI: 10.1371/journal.pone.0194007

The True Swine of America

Wild Boar

Invasive species put a huge stress on local environments and bring with them many problems, especially when it comes to native species. Invasive species are those not native to an area, and are typically introduced to new regions through human intervention. One of the most problematic invasive species today is the wild boar. Although only native to Eurasia and Northern Africa, wild boar can currently be found in every continent in the world excluding Antarctica. They were first introduced to the United States by Spanish explores in the 16th and 18th centuries and have since spread all across the southern parts of the country.

Wild pigs are pose a huge problem in the United States. Each year the U.S Department of Agriculture spends 20 million dollars for the purpose of repairing agricultural and structural damages caused by wild boars. The boars themselves are extreme generalists in diet and habitat meaning they can survive in many different climates and eat a huge range of plants and animals. They also reproduce prolifically and are known as ecosystem engineers meaning they are disruptive to their habitats as they tend to root and wallow the soil. Lastly, these feral hogs tend to populate some of the most bio diverse areas of the the United States (California and the Southeast), and thus disrupt many already imperiled species.

A study done under the USDA-APHIS-Veterinary Services found that 141 imperiled species across the U.S are susceptible to wild boar encounters and impacts. By using previously population spread data for boar and native species, researchers found that 72.7% of imperiled species in the U.S have wild pig range overlap and thus are susceptible to them. Crustaceans being predicted to be most at risk. The study also found that the Southeast, Southwest, and Pacific Southwest regions of the U.S have the biggest boar populations with boars spanning 72.9%, 62.6%, 41.3% of each area respectively.

Within the study the researchers also note that the wild boars are expected to continue their expansion of the United States and expect over 1,000 more watersheds to be infested with them by 2025. Furthermore, the scientists noted that no studies have ever effectively take into account the damages brought along by the many diseases and parasites the boars carry or of resource competition with other species they cause. Thus, many of their estimates for boar impacts and costs could be underestimated.

In conclusion, wild boars are destroying regional species and are taking over many ecosystems. Its clear that more research needs to be done on the full extent of their damages to local habitats as well as in ways humans can stop these beasts from continuing to terrorize the worlds environments. For more information visit https://www.nature.com/articles/s41598-018-23657-z.


McClure, M. L., et al. 2018. A globally-distributed alien invasive species poses risks to Unites States imperiled species. Scientific Reports, 8 (5332).


Increasing salinity throughout U.S. waters

A study published in January of this year, takes a close look at what is causing increased levels of salinity and alkalinity in waterways across the nation. The freshwater salinization syndrome, as they call it, has the potential to impact ecosystems, infrastructure, and the quality of our drinking water. The syndrome can be linked to multiple factors, but human created factors are most influential.

As observed by 232 United States Geological Survey (USGS) sites, 66% of streams and rivers show a statistical increase in pH. This increase is caused by excess salts being dissolved in the water from human use of brines and agricultural fertilizers. This phenomenon is most common in the eastern and midwestern U.S., but also very prominent in other regions. In the northeast, this has caused a trend of increased sodium and chloride levels in surface and groundwater, most likely due to the heavy amount of brine that is applied in the winter months. For the midwest, this increased pH comes from fertilizer and irrigation runoff with high a potassium content, from agricultural lands. In other regions, weathering and mining waste can cause such elevated pH.

High levels of pH caused by increased alkalinity and salinity, can have adverse effects for humans, plants, and marine life that depend on the water. Road salts, a contributor of this, are known to have far reaching ecological impacts, such as reduced fish size and inability to support vegetation in waters and on land. This study acknowledges the harmful effects of excessive use of salts and their unfortunate existence in our streams and rivers. Only 2.5% of water on the planet is fresh, drinkable water for humans, so we ought to care a lot about keeping that small percent clean. Treatment plants can only remove so many pollutants from our waters, and the process of removing salt from water is even more difficult and costly. When applying fertilizers in the spring, or brine in the winter, it is essential that you use as little as possible to prevent further harm to our streams and rivers.



Sources: Kaushal, S. S., Likens, G. E., Michael, P. L.Utz, R. M., Haq, S., Gorman, J., and Grese, M. (2018) Freshwater salinization syndrome on a continental scale. PNAS 115: E574-E583.



They Survived the Holocaust to Battle Cancer

Holocaust memorial Boston

The Holocaust was the genocide of millions of Jews by the Nazis between the years 1939 and 1945. Researchers at Ben-Gurion University of the Negev in Israel published a study in 2018 that found a higher rate of cancer occurrence in Holocaust survivors in Israel compared to those who did not experience the Holocaust. There is very little information regarding cancer in this group of individuals. All legal decisions concerning financial assistance for Holocaust survivors fighting cancer is based only on one former study. Keeping this in mind, the researchers conducted a comprehensive study that took into account misleading cancer risk factors like age, obesity, diabetes, and smoking.

The study was conducted on 294,543 individuals who were Holocaust survivors based on recognition status as defined by the Holocaust Survivor Benefits Law. Data analysis was done on some of the most prevalent cancers in Israel, cancers of the lungs, colon, bladder, melanoma, breast, and prostate. Analysis for the last two cancers were conducted only on women and men respectively. The occurrence of all six types of cancer was high among Holocaust survivors. The RR, ratio of risk in the exposed (Holocaust survivors), compared to the unexposed (no Holocaust experience) was high for all cancer types. As an example, lung cancer, bladder cancer, and melanoma all showed an RR of 1.2. Based on the fact that the the study took other additional risk factors into consideration, researchers concluded that being a Holocaust survivor is an independent risk factor for all six types of cancer that were explored.

Holocaust survivors who were enrolled in the study were born in European countries under Nazi occupation before 1945, immigrated to Israel after 1945 and were alive in the year 2000. Researchers who conducted the study explain the results as possible consequences of  extreme survival conditions endured during the Holocaust.

Starvation endured by the survivors over extended periods of time could be one explanation for these results.

In addition, continued exposure to toxic wastes due to the proximity of incinerators in concentration camps and, lengthy exposure times to sunlight and resulting UV rays could also be possible reasons.

There are, however, a few shortcomings to this study to be noted. Study participants, despite having immigrated to Israel from a certain country, could have been born in a different one, thus affecting their experience regarding the Holocaust. Furthermore, data analysis was done only based on six common cancer types, when there are many others to be considered. The risk factors based on lifestyle, such as alcohol consumption and exercise habits during the study were not examined. In addition, the Holocaust survivors who died before the year 2000 were not included in the study. This prevents us from taking into consideration their cause of death, which could have shown a higher rate of factors other than cancer.

Taking these advantages and shortcomings into consideration, it can be concluded that the study provided significant results that can be influential in changing the treatment and benefits provided to Holocaust survivors battling cancer in Israel.


Ben, D.R., Biderman, A., Sherf, M., Zamstein, O., Dreiher, J. 2018 Elevated cancer risk in Holocaust survivors residing in Israel: A retrospective cohort study. European Journal of Cancer 95: 85-92

Link to article

Link to Image

Johnny Bravo’s square jaw vs Popeye’s round jaw: A scientific explanation

From left to right, popular cartoon characters Ferb, Phineas, Popeye, and Johnny Bravo.

Do you ever scratch your head and roll your eyes at the ridiculous shapes of cartoon characters? While it can’t be confirmed that Phineas and Ferb have legitimate jaw bones, there may be a scientific explanation to Popeye’s rounded jaw to Johnny Bravo’s square jaw.

A recent study published online in Scientific Reports on April 16, 2018, validated a significant association between mandibular shape and jaw muscle cross-sectional size. In other words, researchers found that thicker jaw muscles produced broader, bigger, and more rectangular jaw bones.

Previous studies have shown that craniofacial skeletal form, or the structure of the bones of the face and jaw, is influenced by mechanical loading. Just as your leg bones get stronger from running, and arm bones get stronger from lifting weights, jaw bones get stronger from chewing. The specific shape of the mandibular bone is also determined by the forces applied to it throughout development. So, you might get your dad’s square jaw through genetics, but you also have a square jaw because of the foods you eat regularly.

Jaw muscles
The temporalis muscle and master muscle of the skull. Credit: Sella-Tunis et al. Labels added.

Scientists at Carmel Research Center in Israel measured jaw shapes and jaw muscles in 382 adult patients by utilizing CT scans. These scans allow for visualization of both bone and muscle, and they specifically looked at (1) the temporalis muscle, which is a large, round muscle that reaches from the side of the skull to the side of the face, and (2) the masseter muscle, which stretches from the lower jaw to the upper jaw.

Jaw bone
Comparison of jaw bone size and shape. Credit: Sella-Tunis et al. Labels added.

Independent of gender and accounting for relative size of individuals, researchers found that larger jaw muscles resulted in a wider ramus, a bigger coronoid projection, a more rectangular base, and a more rounded basal arch. Alternatively, smaller muscles produced a skinnier ramus, a smaller coronoid projection, a narrower and angled base, and a more triangular basal arch (see picture above).

This research can be used in anthropology contexts. Researchers suspect that  hunter-gatherer populations had harder diets, comprised of nuts and meat, which generate larger muscles and produced a stronger jaw line, while agricultural groups that ate more vegetation had skulls that resembled the jaws with smaller muscles. According to this data, it is plausible that Popeye’s spinach diet led to the growth of his softer, rounder jaw, and I would guess that Johnny Bravo is a fan of tougher foods.


Sella-Tunis, T., Pokhojaev, A., Sarig, R., O’Higgins, P., & May, H. 2018. Human mandibular shape is associated with masticatory muscle force. Scientific Reports 8. [doi: 10.1038/s41598-018-24293-3].



Your Deodorant is Causing Air Pollution

When you think of air pollution, you might think of smog or automobile emissions, but think again. Scientists at the Cooperative Institute for Research in Environmental Science at the University of Colorado, Boulder and NOAA have recently published in Science in February 2018 detailing their findings that petroleum-based chemicals used in items like perfumes, soaps, deodorants, and paints emit as much volatile organic compounds (VOC) as motor vehicles. VOCs interact with particles in the air that then develop into smog primarily in the form of ozone, which can trigger asthma as well as scar lung tissue. They can also develop into a type of pollution called PM2.5 that has been linked to heart attacks, strokes, and lung cancer.

Visible Air Pollution in New Delhi, India. Source: Flickr

After regulations were developed in the 1970s to limit VOC emissions from automobiles, commodities like pesticides and personal care products became increasing cause of air pollution. The stricter regulations on car emissions made it more obvious than ever to scientists that household and personal products were a bigger threat to air quality. The study was influenced from past measurements collected of VOCs in California, which had shown higher concentrations of petroleum-based compounds at higher levels than initially predicted from fossil fuel sources alone.

Researchers realized that even though drivers use far more fuel (by weight) than they do personal or household products, gasoline is “stored in an airtight tank, it’s burned for energy, and converted mostly to carbon dioxide,” said Jessica B. Gilman, who was involved in the study. Since carbon dioxide emissions are not smog-forming VOCs, it does not contribute to air pollution as much as a spray or squirt of a petroleum-based product, most of which ends up in the atmosphere.

For their calculations, the authors of the study created a computer model that simulated air quality in Los Angeles by using data from the chemical composition of tailpipe emissions consumer goods. Based off these calculations, they found that roughly half of the VOCs in the air could be attributed to consumer products.

These findings have huge implications for human health, especially because most consumer products are used indoors. The traditional approaches to mitigate air pollution are not enough because they commonly focus on transportation or industrial sources. The regulations need to be extended to consumer products as well to mitigate their effects on environmental and human health. If you want to do more to decrease your impact on air pollution, “natural” products aren’t necessarily the answer, as many chemicals used in these products are incredibly reactive and well still form VOCs. The best option is to use as little household product as you can when you need to.

McDonald, B. b., de Gouw, J. A., Gilman, J. B., Jathar, S. H., Akherati, A., Cappa, C. D., & … Trainer, M. (2018). Volatile chemical products emerging as largest petrochemical source of urban organic emissions. Science359(6377), 760-764.



Kepler Might be Out with the Exoplanets, but TESS Will be Out with the Indo-planets

The size comparison of Earth like exoplanets.

In March 2018, Jack Lissauer of NASA’s Ames Research Center talked about the new phases of NASA’s efforts to identify and research exoplanets. What’s an Exoplanet you ask? Well, it’s a planet that orbits around a star outside of our solar system, much like our Earth does to our Sun. The first phase of this effort started in 2009 when NASA launched the Kepler Spacecraft on a mission to identify Exoplanets. Over the next four years, the Kepler Spacecraft delivered outstanding results by identifying more than 4,000 candidate planets. After detailed investigations, more than 2,000 of these planets were deemed as exoplanets. In 2013, the spacecraft lost two important reaction wheels that control small position adjustments, but it was still able to be repurposed in to see many fields on the sky for short periods of time. This new mission was labeled K2 and the Kepler was able to identify an additional 600 potential exoplanets. Approximately 200 of those planets have been verified. These last 600 planets are closer to the Earth then the previous missions, so it’s possible that one day we might be able to get a closer look! Kepler has done all it can do, so now it’s time to transition to the new phase and launch a planet hunter named TESS.

TESS (Transiting Exoplanet Survey Satellite) will be launched into outer space in 2018. Its primary mission is to survey most of the sky for more exoplanets, but with emphasis on those planets orbiting nearby or around bright host stars. With these criteria, it will make the located planets more suited to follow up observations, such as the characterization of atmospheric compositions and other properties. During the search for exoplanets, more than one third of the planet candidates that were found were associated with target stars. Target stars are only visible every few hours and Kepler was required to continuously monitor them during exploration. When a candidate planet was found around a target star, it was often the case that another candidate planet was found around that same star.  These clusters were called “multis” and the scientists discovered that this configuration was quite common and more likely to yield actual planets after research.  This large number of “multis” told the scientists that flat multi planet systems like our solar system are common in the universe! With all of these great discoveries made by Kepler and K2, who knows what TESS will come up with!


Link: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180002120.pdf


Lissauer, J. 2018. Transiting Planets from Kepler, K2 & TESS. NASA Technical Reports Server.


Does Money Grow from Saving Trees?

money on trees

Profits do come when you save. Authors in a recent study found that when companies invested in green information technology (IT), their profit margins increased. Technology is an unexpected greenhouse contributor. However, our society’s increasing reliance on technology makes it a source of large energy consumption. In a previous study, Belkhir and his coauthors found that information and communication technology (ICTs) devices and services such as smart phones, tablets, displays, and data centers contributed 33% of the total global greenhouse gas emissions in 2010.

Companies feel obligated to adopt sustainable practices in their operations or supply chain due to pressures from various entities like the Business and Sustainable Development Commission, the United Nations, investors, consumers, and governments. These entities want to reduce the environment impact of technology.  When companies reduced the environmental impact of their operations, and incorporated sustainability objectives to their operations and management practices, their profits increased. Furthermore, the incorporation of sustainable objectives reduced the energy consumption from IT equipment, which lowers the energy cost.

From their results, when companies spend more of their overall IT spending on green IT, profits increased, as well as energy consumption. Additionally, the authors found a difference in green IT implementation based on operation-oriented and supplier-oriented platforms. When their operational based implementation, the company conserved more energy and collected more profits. Whereas, a supplier based platform allowed them to conserve with little financial returns.

From a marketing perspective, this may be an ideal way for companies to adopt sustainable practices that supports their business model and finances. However, if the problem of climate change derives from intense extraction of natural resources and human overconsumption, how would this encourage people to change their consumptive patterns? Rather than relying on technology to solve our problems with our changes to our practices. This maybe a good starting point to gather more support. However, do you think this is a lasting solution?


Source: Khuntia, J, Saldanha, T.J.V., Mithas, S., Sambamurthy, V. Information Technology and Sustainability: Evidence from an Emerging Economy.