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Occurring in mammary glands and closely associated tissues, breast cancer is the most common cancer observed in women. For example, in the United States, approximately 1 in 8 women (about 12%) will develop invasive breast cancer over the course of…

The Ebola virus comprises a group of pathogenic agents that cause severe and deadly hemorrhagic fevers in humans and other primates. During 2014 and 2015, an Ebola virus epidemic in West Africa—predominantly, the countries of Guinea, Liberia, and…

Charles Robert Darwin (February 12, 1809 – April 19, 1882) is one of the most celebrated and eminent scientists of the past few centuries, with his broadest and most notable influence arising from his theory of evolution by means of natural…

The critically endangered northern white rhinoceros (Ceratotherium simum cottoni) is a subspecies of white rhino that is on the brink of complete extinction, with only two individuals left in captivity and no known members reported in the wild. The…

A compound found in cranberries, called cranberry proanthocyanidin (cPAC), when used in combination with antibiotics, such as tetracycline, prevents resistance to antibiotics in Escherichia coli and Pseudomonas aeruginosa, according to researchers…

At the Woranso-Mille paleontological site in northern Ethiopia, researchers have discovered a 3.8 million-year-old cranium (skull) belonging to a primitive hominin known as Australopithecus anamensis. Initially unearthed in 2016, but not reported…

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…

The four main blood types (blood groups) found in humans are A, B, AB, and O. Two particular antigens (A and B) determine the specific blood type—A antigen is present in type A blood; B antigen is present in type B blood; both A and B antigens are…

The Komodo dragon (Varanus komodoensis), a type of monitor lizard belonging to the reptilian order Squamata, is a tremendously powerful carnivorous predator. The creature is indigenous to a small number of Indonesian islands, including Komodo, and…

Macular degeneration is the most prevalent cause of vision impairment and loss among people aged 55 years and older. Also termed age-related macular degeneration (AMD), this serious eye condition damages the macula, which is the most sensitive part…

Measles is a highly infectious and communicable disease that is most often contracted in childhood. The infective particle is a ribonucleic acid (RNA) virus—specifically, a paramyxovirus belonging to the genus Morbillivirus. Infected individuals…

Caused by the rod-shaped bacterium Mycobacterium tuberculosis and transmitted by airborne droplets from a diseased individual, tuberculosis (TB) is a chronic infectious disease of humans (and other animals) that destroys body tissue. When M.…

Osteoprotegerin (OPG) is a protein that plays a central role in the regulation of bone mass. Also known as osteoclastogenesis inhibitory factor (OCIF), this naturally occurring protein [a soluble decoy receptor protein that belongs to the tumor…

The bacteria that live in the gut (gastrointestinal tract) constitute a large part of an individual's microbiome (also known as microbiota). In general, gut bacteria, also referred to as the microbial flora of the gut, are harbored by normal,…

The killer whale, or orca, is a predatory cetacean typically found in cold ocean waters. With its easily recognizable black body and distinct white patches over the eyes and around the belly, the orca is a top (apex) predator in the marine…

Psychedelic drugs, also termed hallucinogenic or psychotomimetic drugs, induce transient states of altered perception resembling or mimicking the symptoms of psychosis and are characterized by profound alterations in mood. Because psychedelic drugs…

Statins comprise a group of drugs that are widely prescribed to combat high cholesterol. They suppress the production of cholesterol in the liver and interfere with the formation of plaques in the arteries of the body. As such, these…

Those who fear contracting a water-borne illness caused by pollution at the shore or ingesting a killer amoeba (Naegleria fowleri) at a freshwater lake might instead opt to visit a swimming pool. After all, most pool water is hygienically treated.…

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…

Antisense drugs are gene-based molecules that inhibit the synthesis of proteins (including proteins that cause specific diseases) by binding to the ribonucleic acids (RNAs) responsible for their formation. Specifically, these drugs are…

Soil harbors a vast reservoir of antimicrobial agents. In fact, approximately 80% of all clinically implemented antibiotics are derived from soil-dwelling bacteria. However, many bacteria have evolved methods to evade the effects of various…

Tuberculosis (TB) is a chronic infectious disease of humans (as well as animals) primarily involving the lungs. It is caused by the tubercle bacillus Mycobacterium tuberculosis and is transmitted by pathogenic airborne droplets. Approximately 5–10%…

The warming temperatures attributed to global climate change are making it more difficult for sea turtle populations to survive. As a result of the unusual developmental processes found in many reptiles, including some species of turtles, the sex of…

CRISPR/Cas9 gene editing is a modern technique that targets specific stretches of genetic code and allows editing of deoxyribonucleic acid (DNA) at designated locations. It has been at the forefront of genetic research, providing scientists with the…

The evolutionary transition of certain dinosaurs into modern birds has long been an active area of paleontological research. Because the members of the class Aves are living representatives of theropod dinosaurs, paleontologists have sought fossil…

Mammals possess a certain gene, termed PON1, which encodes a protein enzyme (paraoxonase) that is used to process the cholesterol lipids and fatty acids found in food. This gene evolved millions of years ago and is functionally active in terrestrial…

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…

A newly identified reptilian fossil has pushed back the phylogenetic (evolutionary) family tree of Squamata [the dominant order of living reptiles, comprising lizards, snakes, and amphisbaenians (mostly limbless lizards that resemble worms)] by 75…

Autism, also known as autism spectrum disorder (ASD), is a complex neurodevelopmental condition that impairs the way that a person relates to and communicates with other people. In addition, autism is characterized by restricted, repetitive, or…

Scientists have long thought that dinosaur eggs were white in color and that the evolution of colored eggs in birds was strictly an avian innovation that occurred after the demise of the nonavian dinosaurs. However, technical advancements in the…

Quorum sensing is a process by which bacteria monitor their own population density by detecting the levels of signal molecules that are released by the bacteria. It is a unique phenomenon of cell-to-cell communication, enabling microorganisms to…

Regeneration is the regrowth and replacement of living tissues or organs that have been lost or severely injured through mishaps or disease. The goal of regenerative medicine with regard to humans is to restore the structure and function of any…

Researchers from the Australian Research Council (ARC) Centre of Excellence for Nanoscale BioPhotonics have developed a smartphone microscope that uses the camera’s internal flash as the light source. Their development, described in Scientific…

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…

People consider visual perception to be one of the most trustworthy means of gathering information about the world. However, striking limitations in visual processing occur daily, distorting the precision and completeness of the visual experience…

Colorectal cancer (also termed colon or bowel cancer) is the third most prevalent type of cancer both in men and in women, taking the lives of approximately 400,000 people annually worldwide (including 50,000 people per year in the United States).…

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…

Experimental trials in Guinea, West Africa, confirmed the efficacy of an Ebola virus vaccine, according to a report by World Health Organization (WHO) scientists published in late 2016. The vaccine known as rVSV-ZEBOV (recombinant vesicular…

Recent excavations in Asia unearthed a pristine, three-dimensional fossil of a tiny dinosaur tail with preserved feathers and soft tissues (presumably skin). In 2016, investigators in northern Myanmar (Burma) recovered a piece of Cretaceous-era…

In 2016, animal researchers and geneticists concluded that the giraffe (genus Giraffa), once thought to consist of a single extant species (Giraffa camelopardalis), comprises four distinct species: the northern giraffe (Giraffa camelopardalis),…

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…

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…

Through study of the fossil record, paleontologists can frequently identify when an ancient species or taxon (a grouping of related organisms) first emerged in evolutionary history. (Paleontologists often prefer the term taxon over species because…

Molting (shedding or ecdysis) of the outer cuticular layer of the body is a process vital to arthropods, including insects and crustaceans. This profound endocrinological and physiological process has undoubtedly helped ensure the evolutionary…

Traditionally, the lowest-pitched (bass) instruments have provided the rhythmic foundation in musical ensembles. Researchers from McMaster University, Hamilton, Ontario, Canada, reporting in the Proceedings of the National Academy of Sciences (June…

A new species of orangutan has been identified in the Batang Toru forest ecosystem in northern Sumatra, Indonesia. Genetic and morphological evidence, as well as behavioral data, have confirmed that the Tapanuli orangutan (Pongo tapanuliensis) is…

Tiny granules found within the pollen sacs of numerous species of flowers may play a key role in allergic reactions associated with pollen. Measuring less than 4 micrometers (μm) in diameter (most being less than 1 μm), these granules are called…

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…

A magnitude 5.1 nuclear test was detected 376 km (234 mi) NE of Pyongyang, North Korea (DPRK) on January 6, 2015 at 10:30 a.m. local time (01:30 UTC), according to the U.S. Geological Survey (USGS). The event was picked up at seismic stations around…

High within the coldest and driest continent, Antarctica, lies what may be an environment too hostile to support life, according to a team of scientists from Canada and the United States. They reported finding no evidence of microbial life in the…

The emergent discipline of evolutionary epidemiology recognizes that pathogens (disease-causing organisms) are biological entities that can evolve quickly to take advantage of ecological or environmental changes that promote their transmission.…

Extremophiles are microorganisms that thrive in environmental conditions hostile to most life, including extremes of temperature (both high and low), acidity or alkalinity, salt concentration, and pressure. Most extremophile microorganisms are…

Infection caused by methicillin-resistant Staphylococcus aureus (MRSA) is a serious medical condition and often leads to death. Although the MRSA infection was once confined predominantly to patients in hospital settings (termed hospital- or…

Nerve gases, also known as nerve agents, are highly toxic organophosphorus compounds developed for use as chemical weapons. The chemical formula for the nerve agent Sarin, for example, is [(CH3)2CHO]CH3P(O)F. Nerve agents are similar in function and…

The study of the neural basis of animal behavior is known as neuroethology. It is a combination of two disciplines: neurobiology, the study of the nervous system, and ethology, the study of animal behavior. Neurobiology describes how the nervous…

Light provides many organisms with both energy and information about their surroundings, which is why these organisms commonly display motile responses to light. Such movements of motile organisms or free plant parts in response to light stimulation…

Marfan syndrome (or Marfan's syndrome) is a connective-tissue disorder that manifests through distinctive skeletal and ocular changes as well as congenital heart disease. A mutation in the gene (FBN1) that normally directs the body to make…

Biologic drugs, also known as biologics or biologicals, are produced using living organisms. Various classic biologics, such as the medical human insulin taken by diabetics, have been made by biotechnology processes for some decades. What is…

Caenorhabditis elegans is a small, unsegmented, transparent member of the order Rhabditida in the phylum Nematoda (Nemata). Measuring approximately 1 millimeter in length in its adult form, this roundworm is typically found in soil, often feeding on…

Diauxic growth is the diphasic (two-phase) growth response seen in a culture of microorganisms making a phenotypic adaptation to the addition of a second substrate. This phenomenon was discovered and named diauxie in the early 1940s by the French…

For nearly 50 years, marine chemists have generally accepted that when microscopic organic compounds in seawater, known as dissolved organic carbon (DOC), sank into the deep ocean below 1000 m in depth, they became resistant to microbial…

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…

Fibroblasts are large, flat, stellate or spindle-shaped connective tissue cells found in virtually all animal organs. They constitute the most common type of cell in mammalian connective tissue, which is fibrous and made largely of collagen, the…

In the Afar region of Ethiopia, paleoanthropologists unearthed a 2.8 million-year-old jawbone (mandible) that was provisionally assigned to the genus Homo [the genus of human beings, including modern humans (Homo sapiens) and other extinct…

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…

Macrophages are large phagocytic cells that detect, engulf, and destroy foreign particles, microbes, and other pathogens. When nonmotile, they are often referred to as histiocytes. They reside in every tissue of the body and play major roles in…

Woolly mammoths (Mammuthus primigenius) once inhabited most of Europe and the northern halves of North America and Asia during the Late Pleistocene Epoch. Dating back to approximately 400,000 years ago, these members of the mammalian order…

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…

Purkinje cells are large neurons in the cortex of the cerebellum of vertebrate animals that play a prominent role in regulating and maintaining the proper function of motor movements. They are arranged as a single layer of cells between the…

The increasing resistance of many common disease-causing bacteria to antibiotics poses a global health crisis. However, a powerful compound called teixobactin, belonging to a new class of antibiotics (specifically, a novel class of peptidoglycan…

Convergent evolution, or evolutionary convergence, is a term used to describe instances in which species from different taxonomic groups have evolved a similar form or body plan. In these cases, separate and unrelated organisms have independently…

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…

The term epigenome means “in addition to, above, or outside of the genome.” Fundamentally, it consists of various chemical tags or structures that mark and modify the genome (genetic endowment) of a species in a way that can turn certain genes…

The U.S. Food and Drug Administration (FDA) on November 22, 2013 approved the first H5N1 avian influenza (bird flu) adjuvanted vaccine for adults. An adjuvant is a substance added to a vaccine that stimulates the body's immune response to an…

Histamine is a biologically active amine compound with a molecular formula of C5H9N3. It is formed by the decarboxylation of the amino acid histidine and is widely distributed in animal and plant tissues throughout nature. In particular, it is…

Extinction can be defined as the disappearance and death of a type of organism or group of organisms, particularly at the species level. Mass extinctions of numerous species have occurred throughout the history of life on Earth, and they continue to…

Obesity is an excessive accumulation of body fat that confers a variety of health risks, including diabetes, cardiovascular disorders, arthritis, and some types of cancerous tumors. The risk to health is determined by the amount of body fat, the…

The prominent, spiraling tusk that emerges from the head of the unusual whales called narwhals may serve a variety of uses for these animals, including acting as a water-salinity detector, according to recent studies.The narwhal (Monodon monoceros)…

Synthetic biology is the study and technology of living systems that incorporate genetic circuits, artificial enzymes, or other cellular components designed by humans to perform certain functions. It builds on sophisticated advances in genetic…