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Humans have used dried bovine dung (manure) as a fuel source since prehistoric times. In India, for example, many people burn cow or buffalo dung for cooking fuel. This bioresource provides a low-cost fuel as well as an efficient means of waste…

Neuroscientists have long sought to explain how the brain correctly recognizes a stimulus despite the stimulus appearing under different circumstances with widely variable external factors. For example, with regard to olfactory stimuli, humans can…

Researchers are learning more about how plants respond to "alarm signals" released by other plants that are under attack by herbivores. To warn conspecifics about predators, many animals issue alarms by vocalizing or emitting odors. In the case of…

Studies have shown that all classes of vertebrates—and even some invertebrate species—have the cognitive ability to discriminate among different quantities. For example, many kinds of studied animals can distinguish specific numbers of objects in…

Mercury and its compounds are highly toxic—that is, they cause harmful effects to living organisms. Mercury pollution is found in water, air, and soil worldwide. According to the United Nations Environment Programme, the top anthropogenic sources of…

To bolster food security in a warming world, engineers are developing a coating that could better protect seeds, such as beans, from drought in semiarid regions. The coating mimics a mucilage-based hydrogel produced naturally by some seeds, such as…

Approximately 75% of flowering plants—including about a third of agricultural food crops—depend on the distribution of pollen by an array of animals known collectively as pollinators. These animals include insects such as bees and wasps…

In recent years, researchers have made considerable progress toward producing renewable energy in the form of hydrogen fuel through the electrolysis of water. In the most basic electrolytic cell, an electric current drives a chemical reaction at two…

Atmospheric ozone plays a critical role in the biosphere by absorbing harmful ultraviolet radiation in the stratosphere—the layer of the atmosphere about 10 to 50 km (6 to 30 mi) above Earth’s surface. Since the adoption of the Montreal Protocol in…

In the future, will global demand for coffee outstrip supply? The International Coffee Organization thinks so, based on droughts in Central America, crop-destroying freezing weather in Brazil, and global climate change. In general, coffee is a very…

A new mathematical approach called emulation dramatically decreases the amount of time necessary to solve equations describing key properties of atomic nuclei. The approach will help physicists run simulations far more quickly—and without the need…

Forest fires are becoming more problematic across the globe. For example, climate change has extended fire season in the United States by about 80 days since 1970 because of extreme weather events, such as prolonged drought, according to the U.S.…

Scrap tires are a common waste material, although markets do exist. According to the U.S. Tire Manufacturers Association, of the roughly 270 million scrap rubber tires generated each year in this country, about 100 million tires are used as fuel;…

Researchers at Northwestern University, Evanston, Illinois, USA, have developed a virus catcher of sorts—that is, a sticky and absorbent surface coating that traps droplets and aerosols (microdroplets) that land on the coating. Most often, fine…

Researchers at Purdue University in Indiana, United States, have developed the whitest white paint on record, based on its ultrahigh reflection rating. By incorporating a pigment called barium sulfate (BaSO4) at the highest concentration possible,…

Wildfires are a natural phenomenon in many ecosystems, including forests along the U.S. Pacific West Coast, as natural fires serve to rejuvenate ecological communities. However, from mid-August through mid-September 2020, forests in California,…

Cosmochemists have discovered the oldest solid material known to exist on Earth. The material, stardust, consists of silicon carbide grains measuring around one micrometer in size. The grains date back approximately 7 billion years, or about 2.5…

Microplastics are raining down on national parks and other protected areas in the western United States at the rate of about 132 pieces of microplastic per square meter every day, according to a report in the journal Science (June 2020).…

Wildfires, also termed bushfires or forest fires, are currently devastating large swaths of land in Australia. Detrimental ecologic consequences of these uncontrolled combustions of forest fuels and vegetation are numerous. One of the most serious…

The American beech (Fagus grandifolia) is native to forest regions east of the Mississippi River and is a key tree species in the United States. In particular, it is very abundant from Ohio to the New England states. The tree is also found in the…

Many questions concerning the sustainable production of biofuels have emerged over recent years in terms of land and water use, pollution from fertilizer and pest-control chemicals, greenhouse-gas production, net energy production, and whether…

If you think converting seawater to fuels that can power ships is a fantasy, think again. Researchers at the U.S. Naval Research Laboratory in Washington, D.C., have, in fact, accomplished this feat. In addition, the U.S. Navy has received a patent…

Fingerprint identification is a widely used forensic method for linking an individual to a crime scene. Investigators at a crime scene can find invisible (latent) fingerprints, which consist of natural skin oils, by "dusting" surfaces with carbon…

Heroin (C21H23NO5) is a white, crystalline powder synthesized from morphine, a natural alkaloid extracted from the seedpod of the Asian opium poppy plant, Papaver somniferum. It is a powerful opioid drug prepared by the addition of two acetyl groups…

A class of chemicals known as per- and polyfluoroalkyl compounds (PFAS) are particularly worrisome in the environment because they do not biodegrade. For this reason, scientists often refer to PFAS as “forever chemicals.” PFAS’s staying power…

Naturally ventilating a house, such as by opening doors and windows, has long been considered an effective strategy for exhausting indoor air pollutants. However, according to researchers reporting in the journal Science Advances (February 2020),…

Famously durable, diamond is the hardest natural substance that occurs in any significant abundance on Earth. Yet according to a new study, on the nanoscale—a scale size of just billionths of a meter—diamond can, in fact, be bent and deformed. This…

Researchers from Drexel University in Pennsylvania, USA, have synthesized conductive and layered 2D materials known as MXenes (pronounced maxenes) using a water-free process. In doing so, scientists have opened up potential uses of MXenes as…

Many trees in forests worldwide rely on natural fires to create growing conditions necessary to perpetuate the ecosystem, or to stimulate germination. However, for more than 100 years, humans have been suppressing frequent natural low-intensity…

The United Nations has proclaimed 2019 the International Year of the Periodic Table of Chemical Elements (IYPT2019). The same year also marks the 150th anniversary of the publication of Russian chemist Dmitri Mendeleev’s periodic table, containing…

The Joshua tree (Yucca brevifolia) is a remarkable evergreen, treelike plant found only in the southwestern United States. It was named by Mormon settlers in the early 1800s. Upon seeing the limbs of this plant branching upwards to heaven, the…

Plastic is a ubiquitous and life-saving product, but it is also rapidly becoming a significant environmental problem. Globally, less than 10 percent of plastics are recycled, about 12 percent are incinerated, and the vast majority are disposed of in…

For the first time, scientists have observed two molecules meeting and reacting to form new molecules. A team of chemists used lasers to slow down interacting molecules to temperatures far colder than outer space, enabling the team to observe a…

Fentanyl is a synthetic opioid analgesic (pain reliever) that resembles morphine in its action. However, its drug potency is approximately 50 to 100 times more powerful than that of morphine, leading to high rates of both addiction and overdose…

Photosynthesis is a key natural process utilized by plants and is necessary for proper plant growth. Specifically, photosynthesis uses light to manufacture chemical compounds, including organic compounds—primarily carbohydrates—that are derived from…

All freshwater comes from precipitation over land, which is distributed on Earth as blue and green water. Blue water—that is, surface and groundwater—is stored as freshwater in lakes, streams, ice, and snow, as well as below ground. Green water is…

Researchers have produced carbon chips from waste plastic bags for use in making anodes for lithium-ion batteries, according to a report in ACS Omega (December 2018). For the most part, it is very difficult to break down (depolymerize) plastics into…

Physicists have discovered a new state of matter described as a Cooper pair metal. Similar to an ordinary metal, this newfound state of matter conducts electricity with some resistance. However, the carriers of electric charge in this new state are…

Pesticides—including insecticides and herbicides—are chemical products used to control, reduce, or eliminate organisms that are harmful to cultivated plants. However, the use of pesticides on plants that provide foods for human consumption is often…

Plastic shopping bags are convenient to use because they are lightweight and inexpensive, and yet they are also a major source of plastic pollution. People worldwide use an estimated 500 billion to 1 trillion single-use plastic bags each year.…

More apples are consumed worldwide than any other temperate-zone tree fruit. Apples are eaten fresh, processed into jellies and preserves, cooked in pies and pastries, and made into sauces. Therefore, the cultivation of the trees (genus Malus) that…

Seawater desalination involves removing salts and minerals from water and discharging a higher-concentration solution, or brine, to the sea. The brine effluent may affect the water quality (for example, salinity) and organisms—particularly the…

Cannabidiol (CBD) is the predominant cannabinoid (chemical constituent) of the more than 100 cannabinoids found in the hemp variety of the plant Cannabis sativa. There are preliminary, yet unproven, claims that CBD may offer benefits for treating…

Researchers have developed polymeric materials that are able to kill multidrug-resistant bacteria without inducing drug resistance or toxic side effects, according to a report in Nature Communications (March 2018). The polymers, known as…

In an application of green chemistry, researchers reported in the journal Biomaterials (April 2018) the caffeine-catalyzed synthesis of a new class of polymer gels for drug delivery and other biomedical applications. These caffeine-catalyzed gels…

Neonicotinoid insecticides are the most used insecticide worldwide and have been linked to the decline of pollinator insects. In 2018, the European Union banned the outdoor use of three neonicotinoid insecticides: clothianidin, imidacloprid, and…

Handheld electronic devices with plastic casings, such as cell phones, may be exposing users to toxic organophosphate ester (OPE) flame retardants that leach out of these products. Researchers from the University of Toronto reported in Environment…

Neonicotinoids (also termed neonics) comprise a class of insecticides and pesticides that chemically resemble nicotine. They are the most widely used insecticides in the world and are deployed by plant and crop farmers because these chemical…

Humans' contributions to global warming through burning fossil fuels and other actions (for example, detrimental land-use practices) have resulted in sharp increases in the levels of atmospheric carbon dioxide (CO2). These rising levels of CO2 also…

Mathematics is often referred to as the language of nature. A new study further makes this case by demonstrating that the distribution of prime numbers bears a striking similarity to the positions of atoms in materials known as quasicrystals. The…

In early 2018, NASA announced that it had demonstrated a new type of celestial navigation for the first time. Called XNAV, for x-ray pulsar-based navigation, it relies on beams of radiation from pulsars—the cinders of exploded, massive stars. As…

To better understand the nutritional effects (health benefits), chemical composition, growing conditions, and shelf life of microgreens, a team of researchers reviewed the science behind them in the Journal of Agricultural and Food Chemistry…

It is estimated that 1 gram of soil can be inhabited by up to 109 microorganisms and approximately 60,000 bacterial species. Moreover, soil harbors a vast reservoir of antimicrobial agents, and soil-dwelling bacteria have played a key role in the…

Biocontrol, or biological control, is the natural or applied regulation of populations of pest organisms—especially insects—through the role or use of natural enemies. In other words, biocontrol uses living organisms to reduce and eliminate pest…

In the historical development of spectroscopy, following the fundamental studies of crude spectra of sunlight by Isaac Newton in 1672, certain contributions and achievements are especially noteworthy. The significance of using a narrow slit instead…

The biotechnology used in the creation of genetically modified crops is being expanded to encompass the bioengineering of plants that contain therapeutically important proteins and molecules that can be utilized in the manufacturing of…

Bananas (Musa genus) are one of the world's most valuable and popular primary agricultural commodities. However, the most prevalent naturally occurring bananas, that is, those of the Cavendish variety, are being severely decimated by Panama disease…

Global climate change affects all areas of the Earth, with some regions experiencing greater impacts than others. In particular, the Arctic treeline—that is, the southern limit of the Arctic Bioclimate Zone—is being affected to various degrees by…

Hydroxy acids are carboxylic acids that have at least one hydroxyl (OH−) group. These compounds, which are available as α-hydroxy acids, β-hydroxy acids, and polyhydroxy acids, are often used in skin care products. Hydroxy acids were first used in…

Forests absorb and store carbon. If this ability is hampered, then levels of atmospheric carbon will increase and global temperatures will rise, leading to potentially drastic climatic changes. In particular, deforestation (the permanent elimination…

In an attempt to quantify the amount of plastics ever produced and what has happened to them, researchers produced the first global analysis using data collected from plastic industry sources. As reported in Science Advances (July 2017), 8300…

New regulations by the U.S. Food and Drug Administration (FDA) that went into effect on January 1, 2017, banned the use of antibiotics as feed supplements to help livestock and poultry grow faster. The new rules, prohibiting the over-the-counter…

Because of nutrient-poor soil and the high cost of fertilizer, farmers in parts of Africa often produce only one-fifth to one-tenth as much corn (maize) per hectare as farmers in the United States do. Over time, farming in Africa and elsewhere in…

Wildfires are known to emit large amounts of gaseous and particulate pollutants. In an effort to identify and quantify these pollutants, researchers took their instruments to the skies where they sampled and analyzed smoke plumes from aircraft…

Many trees enjoy extremely long lives in comparison to humans and other animals. Yet one group of trees, the bristlecone pines, stands out as the most ancient of all, with individual trees that commonly live for thousands of years, including one…

Cafestol, C20H28O3, is a compound, specifically a diterpene alcohol, found in coffee beans. It is extracted during the coffee-brewing process and may be present in coffee beverages, depending on the preparation method. Consumption of cafestol in…

Spectroscopy is the study of the absorption, emission, or scattering of electromagnetic radiation, ranging from x-rays to radio waves, by atoms or molecules. The spectroscopic techniques are known as spectrometry and the instruments of spectrometry…

Between 2004 and 2014, the total phosphorus content of lakes and streams in the contiguous (lower 48) United States rose, according to surveys by the U.S. Environmental Protection Agency (EPA) reported in the journal Environmental Science &…

Biochar is charcoal made from biomass (organic matter used for energy). A process called pyrolysis, in which biomass is heated to high temperature in the absence of oxygen, produces biochar along with combustible gases (syngas) and oils (bio-oils).…

In an advance for soft robotics, a young technology that finds inspiration in living things, research engineers developed a promising material that imitates the extraordinary flexibility, sensitivity, and luminescence of squids, octopuses,…

Researchers from Northwestern University have developed a structural material, called sulfur concrete, that is based entirely on raw materials that are abundant on Mars. Potentially, it could be used for constructing buildings on the Red Planet.…

Internal combustion engines are very inefficient at converting chemical energy to mechanical energy. Among the energy losses are friction and heat losses. In October 2016, researchers from the Georgia Institute of Technology, Atlanta, United States,…

Concrete and steel have been the materials of choice for constructing high-rise buildings for over 100 years. Definitions of high-rise buildings vary, but according to the U.S. National Fire Protection Association high-rise buildings are 23 meters…

For over fifty years, heat stabilizers, light stabilizers, and antioxidants have been added to polymers to maintain their material properties by preventing their degradation. This chemical adjustment is necessary to extend the life of products such…

Much of coastal and southern California has a Mediterranean climate, which is characterized by cooler, wetter winters and hotter, drier summers. Only drought-resistant plant species can survive without irrigation in this type of climate. Turf grass,…

In humans, taste buds on the tongue have sensory receptors that detect the qualities of water-soluble chemicals in food and convert (or transduce) those stimuli to electrical signals. Nerves then carry the signals to the brain, which processes them…

Defying long-held expectations, chemists from Colorado State University created a polyester biopolymer that can be decomposed back into its monomer constituents. Their accomplishment was all the more surprising because the material with which they…

Two varieties of apples that have been genetically engineered not to turn brown when cut or bruised were cleared in February and March of 2015 for growth and sale in Canada by the Canadian Food Inspection Agency (CFIA) and Health Canada (HC) and in…

The use of certain insects to attack and destroy pests—predominantly other insects—is an intriguing and increasingly popular natural method of biological insect control. In particular, the ichneumon wasp is employed for this purpose to control pest…

Phthalates are esters of 1,2-benzenedicarboxylic acid (phthalic acid) [1] made by reacting phthalic anhydride (2) with alcohols. Phthalates are used mostly as plasticizers—additives to make ridged polymers flexible. Flexible poly(vinyl chloride), or…

Polyelectrolytes, also known as polymer electrolytes and polymeric electrolytes, are water-soluble polymers that contain positively or negatively charged ionic groups; that is, cations (+) or anions (–). They may be natural materials, such as…

An artificial leaf is a solar cell that uses water and an electrical current generated from sunlight to produce hydrogen (for fuel) and oxygen. It is currently in development at laboratories worldwide. If successful, the artificial leaf could serve…

One of the most remarkable features of the sea (marine) turtles that inhabit the tropical and subtropical waters of the world is their homing ability. Throughout the year, sea turtles swim huge distances, often more than 1600 kilometers (1000…

Polymer scientists have developed a siloxane (silicone) polymer that stretches to 5000 percent of its original length and then returns to its unstretched size when released. The scientists presented their work at the 250th National Meeting &…

Advances in aluminum-air battery technology might allow electrically powered vehicles to become more realistic and competitive automotive options for many drivers.At present, most electric vehicles (EVs) are powered by lithium-ion battery packs and…

Recycling or reuse is in most instances environmentally preferable to disposal. Reuse of coal tar as an asphalt-pavement sealant for driveways and parking lots, however, has turned out to be an exception to this rule of thumb. Asphalt and asphaltite…

One of history’s worst agricultural catastrophes was the great Irish potato famine of 1845–1849, which killed more than a million people in Ireland, forced the emigration of 1.5 million others, and fueled resentments between the Catholic and…

Over the next 10 to 20 years, capturing carbon dioxide (CO2)—a powerful greenhouse gas emitted from sources such as fossil-fuel-burning power plants, natural-gas processing plants, bioethanol plants, and cement plants—could become a significant…

Among the goals of organic synthesis are the high-yield production of target molecules with minimal unwanted by-products and the discovery of new molecules and new chemical reactions. In its simplest approach, organic synthesis is done in solution…

Ethylene, CH2=CH2, the most-produced organic chemical in the world, is used to make hundreds of products. The major product is polyethylene, but other important ones include poly(vinyl chloride), polystyrene, antifreeze (ethylene glycol), adhesives,…

The very weak attractive forces between neutral atoms and molecules are known as van der Waals forces. These forces are important for holding molecules together and influencing materials properties such as boiling and melting points, solubility,…

Many parts of the world, particularly in poorer countries, need better tools for identifying unsafe drinking water. A test developed by researchers at the University of Bristol, United Kingdom, seems to show potential as a low-cost technique for…

Click chemistry is a method used in chemical synthesis and polymerization processes in which molecules are interlinked by reactive groups that will only connect with one another. Developed in the laboratory of K. B. Sharpless at The Scripps Research…

Marijuana is the Spanish-derived name for the dried leaves, stems, seeds, and flowering tops of the hemp plant (Cannabis sativa). For thousands of years, humans have consumed marijuana (in edible, smokeable, and vaporized forms) because of its…

Papaya (Carica papaya) is a major fruit crop cultivated in tropical and subtropical regions. The treelike, herbaceous papaya plant grows quickly and typically reaches a height of 6–9 meters (20–30 feet). The commercially important fruits cluster…

Soil organic matter represents a reservoir of stored (sequestered) carbon that slowly cycles between the earth and the atmosphere. It is predominately composed of humus stabilized by clay particles, with the remainder being less stable decaying…

A new polymer has a molecular structure and physical properties very similar to those of lubricin, a protein that lubricates the opposing bone surfaces in moving (articulating) joints of the body. Chemistry researchers from the University of…

Of all the air pollutants, one of the most dangerous to human health is fine-particulate matter (PM2.5)—solid or liquid particles less than 2.5 micrometers in diameter. The health risk for PM2.5 is that these particles can be inhaled deep into the…