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Edward Stuart Russell (1887-1954)

Edward Stuart Russell was born 23 March 1887 to Helen Cockburn Young and the Reverend John N. Russell in Port Glasgow, Scotland. Friends and co-workers alike knew Russell as a quiet and focused, though always kind and helpful person. Trained in classics and biology, Russell's interests drew him to the study of historical and philosophical issues in the biological sciences, particularly morphology and animal behavior. According to Nils Roll-Hansen, Russell was one of the most influential philosophers of biology in the second third of the twentieth century.

Format: Articles

Subject: People

Andrew Francis Dixon (1868-1936)

Andrew Francis Dixon studied human anatomy and egg cells at the turn of the twentieth century in Ireland and Great Britain. Dixon studied the sensory and motor nervous system of the face, the cancellous bone tissue of the femur, supernumerary kidneys, and the urogenital system. In 1927 Dixon described a mature human ovarian follicle. This follicle, Dixon noted, contained an immature human egg cell (oocyte) with a visible first polar body and the beginnings of the second polar body.

Format: Articles

Subject: People

Francis Maitland Balfour (1851-1882)

During the 1870s and early 1880s, the British morphologist Francis Maitland Balfour contributed in important ways to the budding field of evolutionary embryology, especially through his comparative embryological approach to uncovering ancestral relationships between groups. As developmental biologist and historian Brian Hall has observed, the field of evolutionary embryology in the nineteenth century was the historical ancestor of modern-day evolutionary developmental biology.

Format: Articles

Subject: People

Robert Guthrie (1916–1995)

Robert Guthrie developed a method to test infants for phenylketonuria (PKU) in the United States during the twentieth century. PKU is an inherited condition that causes an amino acid called phenylalanine to build to toxic levels in the blood. Untreated, PKU causes mental disabilities. Before Guthrie’s test, physicians rarely tested infants for PKU and struggled to diagnosis it. Guthrie’s test enabled newborns to be quickly and cheaply screened at birth and then treated for PKU if necessary, preventing irreversible neurological damage.

Format: Articles

Subject: People

"Human Toxoplasmosis: Occurrence in Infants as an Encephalomyelitis Verification of Transmission to Animals" (1939), by Abner Wolf et al.

In a series of experiments during mid 1930s, a team of researchers in New York helped establish that bacteria of the species Toxoplasma gondii can infect humans, and in infants can cause toxoplasmosis, a disease that inflames brains, lungs, and hearts, and that can organisms that have it. The team included Abner Wolf, David Cowen, and Beryl Paige. They published the results of their experiment in Human Toxoplasmosis: Occurrence in Infants as an Encephalomyelitis Verification of Transmission to Animals.

Format: Articles

Subject: Experiments, Reproduction, Disorders

Edward Charles Dodds (1899-1973)

Edward Charles Dodds researched the function and effects of natural and artificial hormones on the endocrine system in England during the twentieth century. Though he first worked with hormones such as insulin, Dodds focused on the effects of estrogen in the body and how to replicate those effects with artificial substances. In 1938, along with chemist Robert Robinson, Dodds synthesized the first synthetic estrogen called diethylstilbestrol.

Format: Articles

Subject: People

Wilhelm His, Sr. (1831-1904)

Wilhelm His, Sr. was born on 9 July 1831 in Basel, Switzerland, to Katharina La Roche and Eduard His. He began his medical studies at Basel in 1849 and later transferred to the University of Bern during the winter semester of 1849-1850. A year later, His arrived at the University of Berlin, where he studied under Johannes Müller and Robert Remak. For his clinical training, His attended the University of Würzburg from 1852-1853.

Format: Articles

Subject: People

Wilhelm Roux (1850-1924)

Wilhelm Roux was a nineteenth-century experimental embryologist who was best known for pioneering Entwicklungsmechanik, or developmental mechanics. Roux was born in Jena, Germany, on 9 June 1850, the only son of Clotilde Baumbach and a university fencing master, F. A. Wilhelm Ludwig Roux. Roux described himself as an aloof child, but when he was fourteen he cultivated a passion for science that was encouraged by the director at Oberrealschule in Meiningen.

Format: Articles

Subject: People

Slime mold development video by John Tyler Bonner

This video is composed of a sequence of time lapse films created by John Tyler Bonner in the 1940s to show the life cycle of the cellular slime mold, Dictyostelium discoideum. As only the second person to study slime molds, Bonner frequently encountered audiences who had never heard of, let alone seen, the unusual organism. He therefore decided to create a film to present at seminars in order to introduce his object of study. Bonner created the video for his senior thesis at Harvard University with the help of photographer Frank Smith.

Format: Video

Subject: Organisms

Walter Jakob Gehring (1939-2014)

Walter Jakob Gehring discovered the homeobox, a DNA segment found in a specific cluster of genes that determine the body plan of animals, plants, and fungi. Gehring identified the homeobox in 1983, with the help of colleagues while isolating the Antennapedia (Antp) gene in fruit flies (Drosophila) at the University of Basel in Basel, Switzerland. Hox genes, a family of genes that have the homeobox, determine the head-to-tail (anterior-posterior) body axis of both vertebrates and invertebrates.

Format: Articles

Subject: People

Digit Regeneration Is Regulated by Msx1 and BMP4 in Fetal Mice (2003), by Manjong Han et al.

In the early 2000s, Manjong Han, Xiaodang Yang, Jennifer Farrington, and Ken Muneoka investigated how genes and proteins in fetal mice (Mus musculus) influenced those fetal mice to regenerate severed toes at Tulane University in New Orleans, Louisiana. The group used hind limbs from mice to show how the gene Msx1 (Homeobox 7) functions in regenerating amputated digits.

Format: Articles

Subject: Experiments

Making Visible Embryos (2008- ), by Tatjana Buklijaz and Nick Hopwood

Making Visible Embryos is a 2008 online exhibition of embryos authored and designed by Tatjana Buklijaz and Nick Hopwood who work in the Department of History and Philosophy of Science at the University of Cambridge. Hopwood's research on the history of Ziegler wax models and the use of visual aids to promote the teaching and learning of science is well known.

Format: Articles

Subject: Organizations, Outreach

Light Therapy for Neonatal Jaundice

Light therapy, also called phototherapy, exposes infants with jaundice, a yellowing of the skin and eyes, to artificial or natural light to break down the buildup of bilirubin pigment in the blood. Bilirubin is an orange to red pigment produced when red blood cells break down, which causes infants to turn into a yellowish color. Small amounts of bilirubin in the blood are normal, but when there is an accumulation of excess bilirubin pigment, the body deposits the excess bilirubin in the layer of fat beneath the skin.

Format: Articles

Subject: Technologies

Beadle and Tatum's 1941 Experiments with Neurospora Revealed that Genes Produce Enzymes

This illustration shows George Beadle and Edward Tatum's experiments with Neurospora crassa that indicated that single genes produce single enzymes. The pair conducted the experiments at Stanford University in Palo Alto, California. Enzymes are types of proteins that can catalyze reactions inside cells, reactions that produce a number of things, including nutrients that the cell needs. Neurospora crassa is a species of mold that grows on bread.

Format: Graphics

Subject: Theories, Experiments

Edward Drinker Cope's Law of Acceleration of Growth

The Law of Acceleration of Growth is a theory proposed by Edward Drinker Cope in the US during the nineteenth century. Cope developed it in an attempt to explain the evolution of genera by appealing to changes in the developmental timelines of organisms. Cope proposed this law as an additional theory to natural selection.

Format: Articles

Subject: Theories

Gordon Watkins Douglas (1921-2000)

Gordon Watkins Douglas researched cervical cancer, breach delivery, and treatment of high blood pressure during pregnancy in the US during the twentieth century. He worked primarily at Bellevue Hospital Center in New York, New York. While at Bellevue, he worked with William E. Studdiford to develop treatments for women who contracted infections as a result of illegal abortions performed throughout the US in unsterile environments.

Format: Articles

Subject: People

Ponseti's Treatment for Congenital Clubfoot (1963)

In 1963, Ignacio Ponseti and Eugene Smoley experimentally determined an effective and minimally invasive method of treating congenital clubfoot. Congenital clubfoot is a disorder in which a newborn’s foot is rigidly turned inwards and upwards. During the early 1960s, orthopedists often relied on invasive surgical procedures to treat clubfoot.

Format: Articles

Subject: Experiments

"Mitochondrial DNA and Human Evolution" (1987), by Rebecca Louise Cann, Mark Stoneking, and Allan Charles Wilson

In 1987 Rebecca Louise Cann, Mark Stoneking, and Allan Charles Wilson published Mitochondrial DNA and Human Evolution in the journal Nature. The authors compared mitochondrial DNA from different human populations worldwide, and from those comparisons they argued that all human populations had a common ancestor in Africa around 200,000 years ago. Mitochondria DNA (mtDNA) is a small circular genome found in the subcellular organelles, called mitochondria.

Format: Articles

Subject: Publications, Theories

Beadle's One Gene-One Enzyme Hypothesis

Between 1934 and 1945, George Beadle developed a hypothesis that each gene within the chromosomes of organisms each produced one enzyme. Enzymes are types of proteins that can catalyze reactions inside cells, and the figure shows that each enzyme controls a stage in a series of biochemical reactions. The top box in this figure represents a normal process of enzyme production and biochemical reactions, and the bottom box shows how Beadle's experiments affected the normal biochemical process.

Format: Graphics

Subject: Theories, Processes

Embryos in Wax (2002), by Nick Hopwood

Embryos in Wax: Models from the Ziegler Studio is a history of embryo wax modeling written by science historian Nick Hopwood. Published by the Whipple Museum of the History of Science University of Cambridge and the Institute of the History of Medicine University of Bern, 2002, the book, like the wax models, helps exemplify the visual and material culture of science.

Format: Articles

Subject: Publications

Gamete Intra-Fallopian Transfer (GIFT)

Various techniques constitute assisted reproduction, one of which is gamete intra-fallopian transfer (GIFT). The first example of GIFT involved primates during the 1970s; however, the technology was unsuccessful until 1984 when an effective GIFT method was invented by Ricardo Asch at the University of Texas Health Sciences Center and the procedure resulted in the first human pregnancy. The GIFT technique was created in hopes of generating an artificial insemination process that mimicked the physiological sequences of normal conception.

Format: Articles

Subject: Technologies, Reproduction

Hermaphrodites and the Medical Invention of Sex (1998), by Alice Domurat Dreger

Hermaphrodites and the Medical Invention of Sex, by historian of science Alice Domurat Dreger, was published in 1998 by Harvard University Press. In the book, Dreger describes how many doctors and scientists treated human hermaphrodites from the late nineteenth century to the early twentieth century. She states that during this time period, many physicians and scientists struggled to determine the nature sex, and to support a classification of sex as male or female, many physicians and scientists resorted to viewing a person's gonads for identification of his or her sex.

Format: Articles

Subject: Publications, Theories, Disorders

Julius von Sachs (1832-1897)

Julius von Sachs helped establish plant physiology through his experiments in latter nineteenth-century Germany. Sachs infused the inchoate discipline of plant physiology with experimental techniques and a mechanistic stance, both of which cemented his place as one of the discipline s founders. Sachs trained a generation of plant physiologists, and his stress on experimentation and mechanism influenced biologists in other disciplines, especially embryologist Jacques Loeb.

Format: Articles

Subject: People

Alan Mathison Turing (1912-1954)

Alan Mathison Turing was a British mathematician and computer scientist who lived in the early twentieth century. Among important contributions in the field of mathematics, computer science, and philosophy, he developed a mathematical model of morphogenesis. This model describing biological growth became fundamental for research on the process of embryo development.

Format: Articles

Subject: People

Jacques Loeb (1859-1924)

Jacques Loeb experimented on embryos in Europe and the United States at the end of the nineteenth and beginning of the twentieth centuries. Among the first to study embryos through experimentation, Loeb helped found the new field of experimental embryology. Notably, Loeb showed scientists how to create artificial parthenogenesis, thus refuting the idea that spermatozoa alone were necessary to develop eggs into embryos and confirming the idea that the chemical constitution of embryos environment affected their development.

Format: Articles

Subject: People