Saturday, September 23, 2017

Essential Minerals

In the context of nutrition, a mineral is a chemical element required as an essential nutrient by organisms to perform functions necessary for life. Minerals originate in the earth and cannot be made by living organisms. Plants get minerals from soil. Most of the minerals in a human diet come from eating plants and animals or from drinking water. As a group, minerals are one of the four groups of essential nutrients, the others of which are vitamins, essential fatty acids, and essential amino acids.

The five major minerals in the human body are calcium, phosphorus, potassium, sodium, and magnesium. All of the remaining elements in a human body are called "trace elements". The trace elements that have a specific biochemical function in the human body are sulfur, iron, chlorine, cobalt, copper, zinc, manganese, molybdenum, iodine and selenium.

Most chemical elements that are ingested by organisms are in the form of simple compounds. Plants absorb dissolved elements in soils, which are subsequently ingested by the herbivores and omnivores that eat them, and the elements move up the food chain. Larger organisms may also consume soil (geophagia) or use mineral resources, such as salt licks, to obtain limited minerals unavailable through other dietary sources.

Bacteria and fungi play an essential role in the weathering of primary elements that results in the release of nutrients for their own nutrition and for the nutrition of other species in the ecological food chain. One element, cobalt, is available for use by animals only after having been processed into complex molecules (e.g., vitamin B12) by bacteria. Minerals are used by animals and microorganisms for the process of mineralizing structures, called "biomineralization", used to construct bones, seashells, eggshells, exoskeletons and mollusc shells.

Essential Chemical Elements for Humans

At least twenty chemical elements are known to be required to support human biochemical processes by serving structural and functional roles as well as electrolytes. However, as many as twenty-nine elements in total (including hydrogen, carbon, nitrogen and oxygen) are suggested to be used by mammals, as inferred by biochemical and uptake studies. Calcium makes up 920 to 1200 mg of adult body weight, with 99% of it contained in bones and teeth. Phosphorus makes up about 1% of a person's body weight. The other major minerals (potassium, sodium, chlorine, sulfur and magnesium) make up only about 0.85% of the weight of the body. Together these eleven chemical elements (H, C, N, O, Ca, P, K, Na, Cl, S, Mg) make up 99.85% of the body.

Most of the known and suggested mineral nutrients are of relatively low atomic weight, and are reasonably common on land, or, at least, common in the ocean (iodine, sodium).

Elements Considered Possibly Essential but not Confirmed

Many ultratrace elements have been suggested as essential, but such claims have usually not been confirmed. Definitive evidence for efficacy comes from the characterization of a biomolecule containing the element with an identifiable and testable function. One problem with identifying efficacy is that some elements are innocuous at low concentrations and are pervasive (examples: silicon and nickel in solid and dust), so proof of efficacy is lacking because deficiencies are difficult to reproduce. Ultratrace elements of some minerals such as silicon and boron are known to have a role but the exact biochemical nature is unknown, and others such as arsenic and chromium are suspected to have a role in health, but with weaker evidence. Chromium is considered and essential mineral by the U.S. Institute of Medicine but not for the European Food Safety Authority, which makes the decisions for the European Union. Roles for trace minerals include enzyme catalysis, attracting substrate molecules, redox reactions, and structural or regulatory effects on protein binding.

These elements include bromine, arsenic, nickel, fluorine, boron, lithium, strontium, possibly silicon and vanadium and potentially possibly aluminum, germanium, lead, rubidium, and tin.


Footnote by the Blog Author

The text linked above also notes that “tungsten, lanthanum, and cadmium have specialized biochemical uses in certain lower organisms, but these elements appear not to be utilized by humans.”  Silver has antibacterial properties and gold interrupts chemical processes of rheumatoid arthritis.  Silver and gold have the same valence as copper and may be able to substitute for certain functions performed by copper.

Friday, September 22, 2017

Wind River Movie Summary

Wind River is a 2017 American neo-western murder mystery thriller film written and directed by Taylor Sheridan. The film stars Jeremy Renner and Elizabeth Olsen as a U.S. Fish and Wildlife Service tracker and an FBI agent, respectively, who try to solve a murder on the Wind River Indian Reservation in Wyoming. Gil Birmingham and Graham Greene also star. It premiered at the 2017 Sundance Film Festival and was released on August 4, 2017, by The Weinstein Company.

Plot Summary

It is winter on the Wind River Indian Reservation in Wyoming, U.S. Fish and Wildlife Service agent Cory Lambert discovers the body of Natalie Hanson, an 18-year old resident of the reservation. Her corpse is frozen solid, she is without shoes and proper winter attire, and there is a blood stain on her pants at her groin. Rookie FBI special agent Jane Banner arrives to determine whether a murder has been committed, as the federal government has jurisdiction over capital crimes on reservations. Banner is unprepared for conditions, as she needs to borrow clothing from a local resident. Banner is taken by Lambert and Tribal Police Chief Ben to the body and, after surveying the scene, she orders an autopsy.

The next day, the investigative team learns from Natalie's father that the young woman was dating a new boyfriend, but he doesn't know the man's name or whereabouts. They also learn that Natalie's brother Chip is a drug addict and currently residing with the reservation's local dealers, the Littlefeather brothers, in their double-wide trailer.

Natalie's autopsy returns findings of blunt trauma and sexual violence, and confirms Lambert's assumption that the girl had died from exposure, specifically pulmonary hemorrhage caused by rapid inhalation of sub-zero air during her barefooted flight through the snow. However, the medical examiner is unable to definitively conclude in his report that the victim was murdered, therefore preventing Banner from calling in an additional FBI investigative unit. Banner tells Ben that she will remain to assist and she will not provide an update to her supervisor, as she figures she would be directed to cease being involved.

Banner, Lambert, and Ben visit the Littlefeather property in order to question Chip. They have an armed confrontation with Sam Littlefeather that ends with him dead at Banner's hands, and Chip and another dealer taken into custody. Lambert notices a snowmobile track leading away from the property toward the area where Natalie's body was found. He convinces Banner to hold off interrogating the two young men in order to follow the trail before it snows over. Some distance up the mountain, Lambert discovers a second body, this one male, nude, and heavily ravaged by scavenging wildlife. Chip reveals that Natalie's boyfriend is named Matt and that he works on the security staff at a nearby oil drilling site, where he also lives.

Banner visits Lambert's home and tells him that she has learned that the male body is of Matt Rayburn, who worked as security at the nearby oil drilling site. Lambert tells her about the death of his daughter three years before, whose body was discovered in the snow three years ago, following a party at his house. He and his wife had been out of town.

Accompanied by Sheriff Ben and tribal police officers, as well as local county deputies, Banner approaches the drill site. She meets several of Matt's fellow armed security guards, who claim not to have seen Matt since he stormed off a few days ago following an argument with his girlfriend. As her party is led toward the drill crew's sleeping quarters, which she asked to examine, Lambert has retraced the track up to the second corpse. He follows it over a mountain range, where he finds that it leads directly into the drilling camp, where Banner and the deputies have already arrived. Lambert tries to warn Ben by radio.

At the oil rig site, Banner, Ben, and the deputies meet with the oil rig security. Banner says that Natalie filed a complaint that Matt was missing and she is investigating his disappearance. The oil rig security reveal their knowledge of discovery of Natalie's body and say they had learned this by monitoring law enforcement radio channels. But Natalie's identity was never discussed over the radio. Noticing that the oil rig security are starting to surround Banner, Ben, and the deputies, one of the deputies pulls his weapon. The others immediately follow and all parties are locked in an armed standoff. Banner defuses the situation by claiming federal authority over the others. Everyone walks toward the trailer where Matt had been living.

A flashback shows Natalie going to Matt's trailer, and the two cuddling and discussing plans after making love. His security colleagues interrupt, entering the trailer after a night of hard drinking. Pete, a particularly vulgar crew member, taunts them and provokes Matt to violence, and the team members retaliate by beating him and knocking out Natalie. Pete rapes her. Matt recovers consciousness, attacking Pete and the others. They overwhelm him and beat him to death, but the barefoot Natalie escapes the trailer and runs away.

In present time, Banner tries the door to Matt's trailer, finding it locked. Warned by Lambert, Ben shouts at her to get away, but she is hit by a shotgun blast fired by Pete from inside. A firefight breaks out. Banner is shot in the neck, and Ben and the other officers are killed. As Banner is about to be killed by the remaining security team members, Lambert opens fire from a distance, fatally shooting all except Pete, who flees.

Lambert catches Pete on the mountain and knocks him unconscious. When he recovers, Lambert forces him to confess his actions against Natalie and Matt. He offers him the same chance given Natalie, a barefoot escape toward a distant road. Lambert says that Natalie "was a warrior" and made it six miles before she collapsed and died, but predicts that Pete will not last long enough to reach the highway. The camera shows Pete stumbling through the snow only a few yards before collapsing dead into the snow.

Lambert visits Banner, who is recovering in the hospital, and praises her toughness. He visits Martin Hanson, Natalie's father, finding him sitting in his yard with a gun, having painted his face blue for death and contemplating suicide. Martin tells Lambert that Chip had called from the station, the first time they had spoken in a year. He has decided to go on. Lambert tells Martin that the missing oil crew member had died "with a whimper". He and Martin sit together in the frozen yard, sharing in the grief of their daughters' deaths.

A title card states that the FBI does not keep statistics on missing Native American women, whose numbers remain unknown.

Thursday, September 21, 2017

Molecular Robot Builds Molecules

Scientists Create World’s First ‘Molecular Robot’ Capable of Building Molecules

University of Manchester, September 20, 2017 -- Scientists at The University of Manchester have created the world’s first ‘molecular robot’ that is capable of performing basic tasks including building other molecules.

The tiny robots, which are a millionth of a millimeter in size, can be programmed to move and build molecular cargo, using a tiny robotic arm.

Each individual robot is capable of manipulating a single molecule and is made up of just 150 carbon, hydrogen, oxygen and nitrogen atoms. To put that size into context, a billion billion of these robots piled on top of each other would still only be the same size as a single grain of salt.

The robots operate by carrying out chemical reactions in special solutions which can then be controlled and programmed by scientists to perform the basic tasks.

In the future such robots could be used for medical purposes, advanced manufacturing processes and even building molecular factories and assembly lines. The research will be published in Nature today (21st September).

Professor David Leigh, who led the research at University’s School of Chemistry, explains: ‘All matter is made up of atoms and these are the basic building blocks that form molecules. Our robot is literally a molecular robot constructed of atoms just like you can build a very simple robot out of Lego bricks. The robot then responds to a series of simple commands that are programmed with chemical inputs by a scientist.

‘It is similar to the way robots are used on a car assembly line. Those robots pick up a panel and position it so that it can be riveted in the correct way to build the bodywork of a car. So, just like the robot in the factory, our molecular version can be programmed to position and rivet components in different ways to build different products, just on a much smaller scale at a molecular level.’

The benefit of having machinery that is so small is it massively reduces demand for materials, can accelerate and improve drug discovery, dramatically reduce power requirements and rapidly increase the miniaturization of other products. Therefore, the potential applications for molecular robots are extremely varied and exciting.

Prof Leigh says: ‘Molecular robotics represents the ultimate in the miniaturization of machinery. Our aim is to design and make the smallest machines possible. This is just the start but we anticipate that within 10 to 20 years molecular robots will begin to be used to build molecules and materials on assembly lines in molecular factories.’

Whilst building and operating such tiny machine is extremely complex, the techniques used by the team are based on simple chemical processes.

Prof Leigh added: ‘The robots are assembled and operated using chemistry. This is the science of how atoms and molecules react with each other and how larger molecules are constructed from smaller ones.

‘It is the same sort of process scientists use to make medicines and plastics from simple chemical building blocks. Then, once the nano-robots have been constructed, they are operated by scientists by adding chemical inputs which tell the robots what to do and when, just like a computer program.’

Wednesday, September 20, 2017

Both Left and Right Deny Science

Science Denial Not Limited to Political Right

University of Illinois at Chicago, September 19, 2017 -- In the wake of Hurricanes Harvey and Irma, many claims have been made that science denial, particularly as it relates to climate change, is primarily a problem of the political right.

But what happens when scientific conclusions challenge liberals’ attitudes on public policy issues, such as gun control, nuclear power or immigration?

A new study from social psychologists at the University of Illinois at Chicago and published online in Social Psychological and Personality Science suggests people of all political backgrounds can be motivated to participate in science denial.

UIC researchers Anthony Washburn, a graduate student in psychology, and Linda Skitka, professor of psychology, had participants indicate their political orientation, evaluate fabricated scientific results, and, based on the data, decide what the studies concluded.

Once they were informed of the correct interpretations of the data, participants were then asked to rate how much they agreed with, found knowledgeable, and trusted the researchers’ correct interpretation.

“Not only were both sides equally likely to seek out attitude confirming scientific conclusions, both were also willing to work harder and longer when doing so got them to a conclusion that fit with their existing attitudes,” says Washburn, the lead author of the study. “And when the correct interpretation of the results did not confirm participants’ attitudes, they were more likely to view the researchers involved with the study as less trustworthy, less knowledgeable, and disagreed with their conclusions more.”

These effects were constant no matter what issue was under consideration, which included six social issues — immigration, gun control, climate change, health care reform, nuclear power and same sex marriage — and one control issue — skin rash treatment.

Rather than strictly a conservative phenomenon, science denial may be a result of a more basic desire of people wanting to see the world in ways that fit with their personal preferences, political or otherwise, according to the researchers.

The results also shed light on science denial in public discourse, Skitka added.

“Before assuming that one group of people or another are anti-science because they disagree with one scientific conclusion, we should make an effort to consider different motivations that are likely at play, which might have nothing to do with science per se,” she said.

Tuesday, September 19, 2017

Stronger, "Multivalent" Batteries

A Step Towards Better Batteries ‘Beyond Lithium’
A step towards new “beyond lithium” rechargeable batteries with superior performance has been made by researchers at the University of Bath.

September 18, 2017 -- We increasingly rely on rechargeable batteries for a host of essential uses; from mobile phones and electric cars to electrical grid storage. At present this demand is taken up by lithium-ion batteries. As we continue to transition from fossil fuels to low emission energy sources, new battery technologies will be needed for new applications and more efficient energy storage.

One approach to develop batteries that store more energy is to use “multivalent” metals instead of lithium. In lithium-ion batteries, charging and discharging transfers lithium ions inside the battery. For every lithium ion transferred, one electron is also transferred, producing electric current. In multivalent batteries, lithium would be replaced by a different metal that transfers more than one electron per ion. For batteries of equal size, this would give multivalent batteries better energy storage capacity and performance.

The team showed that titanium dioxide can be modified to allow it to be used as an electrode in multivalent batteries, providing a valuable proof of concept in their development.

The scientists, an international team from the University of Bath, France, Germany, Holland, and the USA, deliberately introduced defects in titanium dioxide to form high concentrations of microscopic holes, and showed these can be reversibly occupied by magnesium and aluminium; which carry more than one electron per ion.

The team also describes a new chemical strategy for designing materials that can be used in future multivalent batteries.

The research is published in the journal Nature Materials.

Dr. Benjamin Morgan, from the Department of Chemistry at the University of Bath, said: “Multivalent batteries are a really exciting direction for battery technology, potentially offering higher charge densities and better performance. New battery technologies are going to be more and more important as we wean ourselves off fossil fuels and adopt greener energy sources.

“There are quite a few technical hurdles to overcome, including finding materials that are good electrodes for multivalent ions. We’ve shown a way to modify titanium dioxide to turn it into a multivalent electrode.

“In the long term, this proof of concept is a possible step towards "beyond lithium" batteries with superior performance.”

The paper "Reversible magnesium and aluminium ionsinsertion in cation-deficient anatase TiO2" is available at:

Monday, September 18, 2017

Avoid Praising Smart Kids

Kids Praised for Being Smart
Are More Likely to Cheat
By Inga Kiderra, University of California San Diego

September 17, 2017 -- An international team of researchers reports that when children are praised for being smart not only are they quicker to give up in the face of obstacles they are also more likely to be dishonest and cheat. Kids as young as age 3 appear to behave differently when told “You are so smart” vs “You did very well this time.”

The study, published in Psychological Science, is co-authored by Gail Heyman of the University of California San Diego, Kang Lee of the University of Toronto, and Lulu Chen and Li Zhao of Hangzhou Normal University in China.

The research builds on well-known work by Stanford’s Carol Dweck, author of “Mindset,” who has shown that praising a child’s innate ability instead of the child's effort or a specific behavior has the unintended consequence of reducing their motivation to learn and their ability to deal with setbacks.

The present study shows there’s also a moral dimension to different kinds of praise and that it affects children at younger ages than previously known. Even the kindergarten and preschool set seem to be sensitive to subtle differences in praise.

“It’s common and natural to tell children how smart they are,” said co-author Gail Heyman, a development psychologist at UC San Diego. “Even when parents and educators know that it harms kids’ achievement motivation, it’s still easy to do. What our study shows is that the harm can go beyond motivation and extend to the moral domain.  It makes a child more willing to cheat in order to do well.”

For their study the researchers asked 300 children in Eastern China to play a guessing game using number cards. In total, there were 150 3-year-olds and 150 5-year-olds. The children were either praised for being smart or for their performance. A control group got no praise at all. After praising the children and getting them to promise not to cheat, the researcher left the room for a minute in the middle of the game. The kids’ subsequent behavior was monitored by a hidden camera, which recorded who got out of their seat or leaned over to get a peek at the numbers.  

Results suggest that both the 3- and 5-year-olds who’d been praised for being smart were more likely to act dishonestly than the ones praised for how well they did or those who got no praise at all. The results were the same for boys and girls.

In another study, published recently in Developmental Science, the same co-authors show that the consequences are similar even when children are not directly praised for their smarts but are merely told that they have a reputation for being smart.

Why? The researchers believe that praising ability is tied to performance pressure in a way that praising behavior isn’t. When children are praised for being smart or are told that they have reputation for it, said co-author Li Zhao of Hangzhou Normal University, "they feel pressure to perform well in order to live up to others' expectations, even if they need to cheat to do so."

Co-author Kang Lee, of the University of Toronto’s Ontario Institute for Studies in Education, emphasized the take-away for the adults in kids’ lives: “We want to encourage children. We want them to feel good about themselves. But these studies show we must learn to give children the right kinds of praise, such as praising specific behavior. Only in this way will praise have the intended positive outcomes.” 

Sunday, September 17, 2017

Singapore's Unvoted President

The Singaporean presidential election of 2017 was the fifth Singaporean presidential election. It was held to elect the successor of the previous President of Singapore, Tony Tan, whose term expired on 31 August 2017. Following amendments to the Constitution of Singapore, the election was the first to be reserved for a particular racial group under a hiatus-triggered model. The 2017 election was reserved for candidates from the minority Malay community, who had not held the presidential office since 1970.

The close of nominations was on 13 September, and polling would have been held on 23 September if two or more candidates were eligible to stand. In accordance with the strict criteria laid out in the national constitution, the Elections Department declared Halimah Yacob to be the only eligible presidential candidate on 11 September. Halimah was consequently declared president-elect on 13 September, and was inaugurated as the eighth President of Singapore the following day.

Background of Singapore Presidency

The President is the head of state of Singapore. Following the Westminster system, the position is largely ceremonial, but enjoys several reserve powers including withholding presidential assent on supply bills and changing or revoking civil service appointments. The current system of holding elections for the Presidency began with the 1993 election, with the election of Ong Teng Cheong. Before then, the President was selected by Parliament.

There are strict requirements for prospective presidential election candidates, and whether a candidate meets the qualifications or not is decided by the Presidential Elections Committee (PEC), who are given the task of issuing a certificate of eligibility (COE) to prospective candidates.

The Presidency is, by the rules of the Constitution, required to be nonpartisan.

Parliamentary Reforms

In his speech to Parliament on 27 January 2016, Prime Minister Lee Hsien Loong said that it was timely to review the eligibility criteria of the Elected Presidency. On 10 February 2016, a Constitutional Commission consisting of nine individuals and chaired by Chief Justice Sundaresh Menon was formed. In its report released on 7 September 2016, the Commission recommended the following key changes:

  1. The election should be reserved for a racial group if it is not represented for five terms, or 30 years. If there are no eligible candidates from that group, the election would be opened to candidates of all races, and the "reserved election" would be deferred to the next Presidential election.
  2. The Council of Presidential Advisers (CPA) should be increased from six to eight members, with two alternate members. The President would have to consult the CPA on all monetary issues related to the financial reserves and all key public service appointments.
  3. A qualifying candidate from the private sector should be a senior executive managing a company with at least S$500 million in shareholders' equity. Previously, such a candidate had to be a chairman or CEO of a company with at least S$100 million in paid-up capital.
  4. For qualifying candidates from both the public and private sectors, the length of time that the candidate has held office should be doubled to six years.
  5. The public sector offices of Accountant-General and Auditor-General should be removed from automatic qualification.
  6. An applicant's entire qualifying tenure should fall within a 15-year period preceding Nomination Day.

The government announced in a White Paper published on 15 September 2016 that it has broadly accepted the recommendations, including the first three changes above. The government did not accept the three other proposed changes, preferring to adopt a "cautious" approach given the other concurrent changes to other aspects of eligibility criteria. On 8 November 2016, PM Lee, under the advice from Attorney-General, announced that the 2017 Presidential Election will be reserved for candidates from the Malay community.

The rules for campaigning have also been modified. Rally sites will no longer be designated for the candidates. All candidates are required to apply for police permit on their own to hold a rally. Also, candidates are required to sign a statutory declaration to affirm that they understand the roles of a President. These rules are purportedly made to ensure that the candidates campaign in a "dignified" manner.