Key concepts Chemistry Acids Bases Temperature Physiology Molecular biology Introduction Your liver is important for cleaning up any potentially dangerous substances you consume. But how does it do it?—With a little help from some complex chemistry. Within your liver, as within every tissue in the body, many chemical reactions occur. Often these reactions require “help” to happen at a faster speed, and this can be supplied by enzymes—tiny types of proteins....
COPENHAGEN—One thing is clear under this city’s low, leaden skies: a ton of carbon dioxide emitted in India is the same as a ton of carbon dioxide emitted in the U.S. And while some notable contrarians are present here at the United Nations’ climate summit, their presence is going largely unnoticed because representatives from most countries accept the basic physics of a molecule of carbon dioxide trapping heat in the atmosphere....
In this space last September, I broached the culturally charged subject of eating insects. Eating them on purpose. Insects are plentiful, a great source of protein, easy to raise and much more environmentally friendly than the more familiar (to Westerners, anyway) vertebrates widely available at your deli counter: cows, chickens and pigs. Let’s turn that plague into a plate of locusts. I come not to bury bugs but to praise them further....
Did you like this article? Editorial Review This article has been reviewed for accuracy, reliability and adherence to academic standards prior to publication. The apparatus of colonial government in the Spanish Empire consisted of multiple levels, starting with the monarchy and Council of the Indies at the top and moving down to the viceroy, audiencias, mayors, and local councils. The system was designed to extract wealth from the colonies and to spread the Christian faith, but these two aims were often in conflict, as were the various branches of colonial government throughout the imperial period....
Did you like this article? Editorial Review This article has been reviewed for accuracy, reliability and adherence to academic standards prior to publication. Titus Flavius Josephus (36-100 CE), the Jewish historian, is the main source for understanding Second Temple Judaism in the 1st century CE. In the last decades of the 1st century CE, he wrote The Jewish War, the Antiquities of the Jews, Against Apion, and The Life of Flavius Josephus....
Did you like this article? Editorial Review This article has been reviewed for accuracy, reliability and adherence to academic standards prior to publication. The stone head sculptures of the Olmec civilization of the Gulf Coast of Mexico (1200 BCE - 400 BCE) are amongst the most mysterious and debated artefacts from the ancient world. The most agreed upon theory is that, because of their unique physical features and the difficulty and cost involved in their creation, they represent Olmec rulers....
Did you like this article? Editorial Review This article has been reviewed for accuracy, reliability and adherence to academic standards prior to publication. The lives of women in ancient Mesopotamia cannot be characterized as easily as with other civilizations owing to the different cultures over time. Generally speaking, though, Mesopotamian women had significant rights, could own businesses, buy and sell land, live on their own, initiate divorce, and, though officially secondary to men, found ways to assert their autonomy....
Constant warmth punctuated by repeated winter heat waves stymied Arctic sea ice growth this winter, leaving the winter sea ice cover missing an area the size of California and Texas combined and setting a record-low maximum for the third year in a row. Even in the context of the decades of greenhouse gas-driven warming, and subsequent ice loss in the Arctic, this winter’s weather stood out. “I have been looking at Arctic weather patterns for 35 years and have never seen anything close to what we’ve experienced these past two winters,” Mark Serreze, director of the National Snow and Ice Data Center, which keeps track of sea ice levels, said in a statement....
This is the fifth article in the Mind Matters series on the neuroscience behind visual illusions. Scientists did not invent the vast majority of visual illusions. Rather, they are the work of visual artists, who have used their insights into the workings of the visual system to create visual illusions in their pieces of art. We have previously pointed out in our essays that, long before visual science existed as a formal discipline, artists had devised techniques to “trick” the brain into thinking that a flat canvas was three-dimensional, or that a series of brushstrokes in a still life was in fact a bowl of luscious fruit....
By Alex Dobuzinskis LOS ANGELES, Sept 1 (Reuters) - Climate change could put a type of oceanic bacteria into evolutionary overdrive in a way that could pose a threat to its long-term survivability and its important role in the food chain, according to a study published on Tuesday. The research published in the journal Nature Communications focuses on trichodesmium, a cyanobacteria found in tropical and subtropical waters such as the Red Sea, the Great Barrier Reef off Australia’s coast, areas around Hawaii and the Caribbean....
The head of the US Environmental Protection Agency (EPA) has announced that the backlog of new chemicals that were stuck in the agency’s review processes has been eliminated. The news has attracted both praise and criticism. The updated Toxic Substances Control Act (TSCA), which regulates new and existing chemicals in the US, mandates that the EPA review chemicals submitted to the agency for approval and make a safety determination prior to them being able to enter the marketplace....
This summer, Ronald Herberman, director of the University of Pittsburgh Cancer Institute, sent a memo to staffers warning them to limit their cell phone use and to use hands-free sets in the wake of “growing evidence that we should reduce exposure” to cell phone radiation. Among the possible consequences: an increased risk of brain cancer. Five months later, a top official at the National Cancer Institute (NCI) told a congressional panel that published scientific data indicates cell phones are safe....
The Food and Drug Administration this week issued a stern health advisory once again warning parents not to give babies under two years of age over-the-counter (OTC) cold and cough medicine because of potentially “serious and life-threatening side effects.” This includes decongestants, expectorants, antihistamines and antitussives (cough suppressants) that you can pick up at pharmacies and supermarkets, including Wyeth’s Robitussin, Novartis, AG’s Triaminic and Johnson & Johnson’s Tylenol Plus Cold. “The FDA strongly recommends to parents and caregivers that OTC cough and cold medicines not be used for children younger than two,” Charles Ganley, director of the FDA’s Office of Nonprescription Products said....
Catching a fly isn’t easy, as anyone who’s ever tried to swat one knows. Why are they so hard to catch? It could be because they maneuver like fighter jets, a new study shows. Using high-speed video cameras, a team of researchers captured the lightning-fast wing and body motion of fruit flies as the insects performed rapid, banked turns to avoid a looming threat. The team also used giant, robotic flies to understand how the sprightly pests performed these aerobatics....
By Katherine Bourzac of Nature magazine The highest possible resolution images — about 100,000 dots per inch — have been achieved, and in full-color, with a printing method that uses tiny pillars a few tens of nanometers tall. The method, described today in Nature Nanotechnology, could be used to print tiny watermarks or secret messages for security purposes, and to make high-density data-storage discs. Each pixel in these ultra-resolution images is made up of four nanoscale posts capped with silver and gold nanodisks....
By Zoë Corbyn of Nature magazineA prisoner’s chance of parole depends on when the judge hearing the case last took a break, say researchers who have studied decisions in Israeli courts. As judges tire and get hungry, they slip towards the easy option of denying parole, say the researchers.The bias could apply in any situation in which people make sequential decisions, such as doctor’s consultations, university admissions or grant-review panels.Jonathan Levav of Columbia Business School in New York and his colleagues analyzed 1,112 parole hearings for inmates of four Israeli prisons, made by eight judges over a ten-month period....
The annual Eta Aquarid meteor shower and an annular solar eclipse both occur at the beginning of May, while a less impressive lunar eclipse is set to take place at the end of the month, but that isn’t all. Constellations, planets and other celestial bodies can also be spotted in various parts of the sky throughout the month, weather permitting. “As night falls, look for Jupiter shining in the west,” Nancy Calo from the Space Telescope Science Institute said during her narration of a video highlighting May stargazing....
You may have read headlines last fall along the lines of “Have you got a hot mom? Chances are your wife will be a looker, too.” That one was courtesy of New Scientist, but other media outlets, including the BBC and the Guardian, also covered a study in Proceedings of the Royal Society B that seemed to provide evidence for the Oedipus complex described by Sigmund Freud and expanded by his protégés: Men pick women who look like their mothers, and women pick men who resemble their fathers....
Hot on the heels of last week’s announcement that two labs, one in Japan and one in Wisconsin, had transformed human skin cells into cells that act a lot like embryonic stem cells, comes an improvement in one of the methods. In the afterglow of the breakthroughs came some important notes about both of the groups’ techniques, which involved inserting four genes into the cells that coded for transcription factors that in turn activate other genes in the cell: The University of Wisconsin group used fetal and newborn fibroblasts (connective tissue cells that aid wound healing); the University of Kyoto researchers used fibroblasts from a 36-year-old woman and a 69-year-old man....
NASA’s shuttle program, set to make its final flight later this week, has resulted in the death of 14 astronauts. But it could have been a lot worse. The agency’s fleet of 100-ton orbiters faced numerous imminent threats for more than 30 years, both on the Earth and traveling at 28,000 kilometers per hour a slice above its surface. Some are well-documented, but many drew little public attention, let alone scrutiny....
