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Sir D'Arcy Wentworth Thompson (1860-1948)

Known by many for his wide-reaching interests and keen thinking, D'Arcy Wentworth Thompson was one of Britain's leading scientific academics in the first few decades of the twentieth century. A prodigious author, Thompson published some 300 papers, books, and articles in the biological sciences, classics, oceanography, and mathematics. He was a famous lecturer and conversationalist-a true "scholar-naturalist," as his daughter wrote in her biography of her father.

Format: Articles

Subject: People

"Behavioral Thermoregulation by Turtle Embryos" (2011), by Wei-Guo Du, Bo Zhao, Ye Chen, and Richard Shine

In "Behavioral Thermoregulation by Turtle Embryos," published in Proceedings of the National Academy of Sciences in April, 2011, Wei-Guo Du, Bo Zhao, Ye Chen, and Richard Shine report that turtle embryos can move towards warmer temperatures within the egg when presented with a small, 0.8 degrees Celsius gradient. This behavioral thermoregulation may benefit the embryo's fitness by accelerating the rate of development enough to decrease the incubation period by up to four and a half days. Embryos are generally thought to have little control over their surroundings.

Format: Articles

Subject: Publications

The Meckel-Serres Conception of Recapitulation

Johann Friedrich Meckel and Antoine Etienne Reynaud Augustin Serres developed in the early 1800s the basic principles of what later became called the Meckel-Serres Law. Meckel and Serres both argued that fetal deformities result when development prematurely stops, and they argued that these arrests characterized lower life forms, through which higher order organisms progress during normal development. The concept that the embryos of higher order organisms progress through successive stages in which they resemble lower level forms is called recapitulation.

Format: Articles

Subject: Theories

Transposition of the Great Arteries (TGA)

Transposition of the great arteries or TGA is a potentially fatal congenital heart malformation where the pulmonary artery and the aorta are switched. The switch means that the aorta, which normally carries oxygenated blood, carries deoxygenated blood. There are two types of the malformation, d-TGA where no oxygen reaches the body and l-TGA where some oxygenated blood circulates. In the US, the Centers for Disease Control estimate that about 1,901 infants are born each year with TGA, or about one for every 2,000 births.

Format: Articles

Subject: Disorders

Stanley Paul Leibo (1937–2014)

Stanley Paul Leibo studied the cryopreservation of embryos in the US in the twentieth century. Cryopreservation is a method of preserving biological material through freezing. Early in his career, Leibo collaborated with other scientists to study why cells were oftentimes injured during freezing. Later, Leibo and his team accomplished one of the first successful births using previously-frozen mammalian embryos.

Format: Articles

Subject: People, Technologies

Pearl Mao Tang (1922– )

A licensed obstetrician and gynecologist, Pearl Tang worked to improve the health of women and children in Maricopa County, Arizona, during the twentieth and twenty-first centuries. Her work with the Maricopa County Health Department ranged from immunizations to preventing cervical cancer. Tang obtained federal grants and community support to establish various child and maternal health clinics throughout Maricopa County as chief of the Maricopa County Bureau of Maternal and Child Health.

Format: Articles

Subject: People, Outreach

Tucson Woman's Clinic v. Eden (2004)

The case Tucson Woman's Clinic v. Eden (2004) established that some of Arizona's abortion clinic laws violated physicians' and patients' rights to privacy, and it required those laws to be rewritten. The laws required most abortion providers to be licensed with the Arizona Department of Health Services and to submit to all the regulations the Department established for abortion clinics. The regulations allowed the state to search abortion clinics without warrants and to access patient records and ultrasound prints, among other provisions.

Format: Articles

Subject: Legal

Neonatal Jaundice

Neonatal jaundice is the yellow discoloration of the skin and eyes due to elevated bilirubin levels in the bloodstream of a newborn. Bilirubin is a byproduct of the breakdown of red blood cells. Jaundiced infants are unable to process bilirubin at a normal rate or they have an abnormally high amount of bilirubin in their bloodstream, resulting in a buildup of the yellow colored bilirubin. That build up is called hyperbilirubinemia and is the cause of jaundice.

Format: Articles

Subject: Disorders

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

Johann Friedrich Blumenbach (1752-1840)

In eighteenth century Germany, Johann Friedrich Blumenbach studied how individuals within a species vary, and to explain such variations, he proposed that a force operates on organisms as they develop. Blumenbach used metrical methods to study the history of humans, but he was also a natural historian and theorist. Blumenbach argued for theories of the transformation of species, or the claim that new species can develop from existing forms.

Format: Articles

Subject: People

Dizhou Tong (1902-1979)

Dizhou Tong, also called Ti Chou Tung, studied marine animals and helped introduce and organize experimental embryology in China during the twentieth century. He introduced cellular nuclear transfer technology to the Chinese biological community, developed methods to clone organisms from many marine species, and investigated the role of cytoplasm in early development. Tong's administrative and scientific leadership in the fields of marine, cellular, and developmental biology contributed to China's experimental embryology research programs.

Format: Articles

Subject: People

"Viable Offspring Derived from Fetal and Adult Mammalian Cells" (1997), by Ian Wilmut et al.

In the 1990s, Ian Wilmut, Jim McWhir, and Keith Campbell performed experiments while working at the Roslin Institute in Roslin, Scotland. Wilmut, McWhir, and Campbell collaborated with Angelica Schnieke and Alex J. Kind at PPL Therapeutics in Roslin, a company researching cloning and genetic manipulation for livestock. Their experiments resulted in several sheep being born in July 1996, one of which was a sheep named Dolly born 5 July 1996.

Format: Articles

Subject: Experiments

Experimental Studies on Germinal Localization (1904), by Edmund B. Wilson

At the turn of the twentieth century, Edmund B. Wilson
performed experiments to show where germinal
matter was located in molluscs. At Columbia University in New York City,
New York, Wilson studied what causes cells to differentiate during
development. In 1904 he conducted his experiments on molluscs, and he modified the
theory about the location of germinal matter in the succeeding years. Wilson and others modified the
theory of germinal localization to accommodate results that showed

Format: Articles

Subject: Experiments

Where Are My Children? (1916)

Where Are My Children? is an anti-abortion silent film released in the United States on 16 April 1916. The film was directed by Lois Weber and Phillips Smalley and produced by Universal Film Manufacturing Company/Lois Weber Productions in Universal City, California. In the film, Weber tells a story of an attorney who wants to have children and raise a family, but his wife chooses to abort her pregnancies, fearing that having children will ruin her social activities. In the early 1900s, information about contraception was not freely available or legal to obtain.

Format: Articles

Subject: Publications

Photograph 51, by Rosalind Franklin (1952)

On 6 May 1952, at King’s College London in London, England, Rosalind Franklin photographed her fifty-first X-ray diffraction pattern of deoxyribosenucleic acid, or DNA. Photograph 51, or Photo 51, revealed information about DNA’s three-dimensional structure by displaying the way a beam of X-rays scattered off a pure fiber of DNA. Franklin took Photo 51 after scientists confirmed that DNA contained genes. Maurice Wilkins, Franklin’s colleague showed James and Francis Crick Photo 51 without Franklin’s knowledge. Watson and Crick used that image to develop their structural model of DNA.

Format: Articles

Subject: Publications

Ian Hector Frazer (1953– )

Ian Hector Frazer studied the human immune system and vaccines in Brisbane, Australia, and helped invent and patent the scientific process and technology behind what later became the human papillomavirus, or HPV, vaccinations. According to the Centers for Disease Control and Prevention of the US, or CDC, HPV is the most common sexually transmitted infection, and can lead to genital warts, as well as cervical, head, mouth, and neck cancers.

Format: Articles

Subject: People

“Pelvic Organ Prolapse Quantification System (POP-Q) - A New Era in Pelvic Prolapse Staging” (2011), by Cristian Persu, Christopher Chapple, Victor Cauni, Stefan Gutue, and Petrisor Geavlete

In 2011, Cristian Persu, Christopher Chapple, Victor Cauni, Stefan Gutue, and Petrisor Geavlete published “Pelvic Organ Prolapse Quantification System (POP-Q) – A New Era in Pelvic Prolapse Staging,” in the Journal of Medicine and Life. In their article, the authors explain the need for a reliable diagnostic method for describing the state of a pelvic organ prolapse, or a condition that can result from weakness or damage to the muscles that support the pelvic organs, sometimes leading to bladder, bowel, and sexual dysfunction.

Format: Articles

Subject: Publications, Processes, Reproduction

Ilya Ilyich Mechnikov (Élie Metchnikoff) (1845-1916)

Ilya Ilyich Mechnikov studied phagocytes, immune function, and starfish embryos in Europe during the late nineteenth and early twentieth centuries. Mechnikov adopted the French form of his name, Élie Metchnikoff, in the last twenty-five years of his life. In 1908, he won the Nobel Prize in Physiology or Medicine with Paul Ehrlich for their contributions to immunology. Mechnikov discovered phagocytes, immune cells that protect organisms by ingesting foreign particles or microorganisms, by conducting experiments on starfish larvae.

Format: Articles

Subject: People

Victor Jollos (1887-1941)

Victor Jollos studied fruit flies and microorganisms in Europe and the US, and he introduced the concept of Dauermodifikationen in the early 1900s. The concept of Dauermodifikationen refers to environmentally-induced traits that are heritable for only a limited number of generations. Some scientists interpreted the results of Jollos's work on Paramecium and Drosophila as

Format: Articles

Subject: People

"Adenocarcinoma of the Vagina: Association of Maternal Stilbestrol Therapy with Tumor Appearance in Young Women" (1971), by Arthur L. Herbst, et al.

Published in 1971, Adenocarcinoma of the Vagina: Association of Maternal Stilbestrol Therapy with Tumor Appearance in Young Women, by Arthurs L. Herbst and colleagues, was the first piece of literature connecting maternal use of the drug diethylstilbestrol (DES), also called stilbestrol, with the development of a rare and severe form of vaginal cancer in young women. Diethylstilbestrol was later classified as an endocrine disruptor, a substance that disrupts the hormonal function of the body in those exposed to it during development or later in life.

Format: Articles

Subject: Publications

The Neuron Doctrine (1860-1895)

The neuron doctrine is a concept formed during the turn of the twentieth century that describes the properties of neurons, the specialized cells that compose the nervous system. The neuron doctrine was one of two major theories on the composition of the nervous system at the time. Advocates of the neuron doctrine claimed that the nervous system was composed of discrete cellular units. Proponents of the alternative reticular theory, on the other hand, argued that the entire nervous system was a continuous network of cells, without gaps or synapses between the cells.

Format: Articles

Subject: Theories

“Diethylstilbestrol in the Prevention and Treatment of Complications of Pregnancy” (1948), by Olive Watkins Smith

In 1948, Olive Watkins Smith published 'Diethylstilbestrol in the Prevention and Treatment of Complications of Pregnancy' in the American Journal of Obstetrics and Gynecology. In 632 women treated with diethylstilbestrol, Smith demonstrated that the drug stimulated the production of progesterone, a hormone that regulates the uterine condition during pregnancy.

Format: Articles

Subject: Publications

John George Children (1777–1852)

John George Children described several species of insects and animals while working at the British Museum in London, England, in the eighteenth and nineteenth centuries. Children also conducted research on chemical batteries called voltaic cells and briefly studied and manufactured gunpowder. One of the species he described, the Children’s python, or Antaresia children, was used in the twenty-first century as the subject of experiments that involved the biological cost of reproduction in snakes.

Format: Articles

Subject: People

Leonard Colebrook’s Use of Sulfonamides as a Treatment for Puerperal Fever (1935–1937)

Between 1935 and 1937, Leonard Colebrook showed that sulfonamides, a class of antibacterial drugs, worked as an effective treatment for puerperal fever. Puerperal fever is a bacterial infection that can occur in the uterus of women after giving birth. At the time of Colebrook’s study, puerperal fever remained a common disease due to both the lack of hygienic practices in hospitals and a treatment for the disease. After successfully using Prontosil, a sulfanilamide, to cure a patient who was going to die from puerperal fever, Colebrook began experiments with the drug.

Format: Articles

Subject: Experiments

The Time Has Come: A Catholic Doctor's Proposals to End the Battle over Birth Control (1963), by John Rock

In 1963, Roman Catholic fertility doctor John Rock published The Time Has Come: A Catholic Doctor's Proposals to End the Battle over Birth Control, a first-person treatise on the use of scientifically approved forms of birth control for Catholic couples. The first contraceptive pill, called Enovid, had been on the market since June 1960, and Rock was one of the leading researchers in its development. In The Time Has Come, Rock explicitly describes the arguments for and against the use of birth control from both a religious and a scientific perspective.

Format: Articles

Subject: Publications, Religion, Reproduction