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Alfred Day Hershey (1908–1997)

During the twentieth century in the United States, Alfred Day Hershey studied phages, or viruses that infect bacteria, and experimentally verified that genes were made of deoxyribonucleic acid, or DNA. Genes are molecular, heritable instructions for how an organism develops. When Hershey started to study phages, scientists did not know if phages contained genes, or whether genes were made of DNA or protein. In 1952, Hershey and his research assistant, Martha Chase, conducted phage experiments that convinced scientists that genes were made of DNA.

Format: Articles

Subject: People

David Reimer and John Money Gender Reassignment Controversy: The John/Joan Case

In the mid-1960s, psychologist John Money encouraged the gender reassignment of David Reimer, who was born a biological male but suffered irreparable damage to his penis as an infant. Born in 1965 as Bruce Reimer, his penis was irreparably damaged during infancy due to a failed circumcision. After encouragement from Money, Reimer’s parents decided to raise Reimer as a girl. Reimer underwent surgery as an infant to construct rudimentary female genitals, and was given female hormones during puberty.

Format: Articles

Subject: Theories

Pfeffer Cell Apparatus

The Pfeffer Zelle (Pfeffer Cell Apparatus), invented by Wilhelm Pfeffer in 1877, measured the minimum pressure needed to prevent a pure solvent from passing into a solution across a semi-permeable membrane, called osmotic pressure. The apparatus provided Pfeffer with a way to quantitatively measure osmotic pressure. Pfeffer devised the apparatus in the 1870s at the University of Basel in Basel, Switzerland, and he described the Pfeffer Cell Apparatus in his 1877 book Osmotische Untersuchungen: Studien Zur Zellmechanik (Osmotic Investigations: Studies on Cell Mechanics).

Format: Articles

Subject: Technologies

“Sierra Leone’s Former Child Soldiers: A Longitudinal Study of Risk, Protective Factors, and Mental Health” (2010), by Theresa S. Betancourt, Robert T. Brennan, Julia Rubin-Smith, Garrett M. Fitzmaurice, and Stephen E. Gilman

In 2010, Theresa S. Betancourt, Robert T. Brennan, Julia Rubin-Smith, Garrett M. Fitzmaurice, and Stephen E. Gliman, published “Sierra Leone’s Former Child Soldiers: A Longitudinal Study of Risk, Protective Factors, and Mental Health” in Journal of the American Academy of Child and Adolescent Psychiatry. The paper describes the results of a longitudinal study of former Sierra Leone child soldiers that examines how protective and risk factors affect children’s post-conflict mental health outcomes over several years of development.

Format: Articles

Subject: Publications

The British Doctors’ Study (1951–2001)

From 1951 to 2001, researchers at the University of Oxford in Oxford, England, conducted the British Doctors’ Study, a study that examined the smoking habits, disease rates, and mortality rates of physicians in Britain. Two epidemiologists, scientists who study occurrence and distribution of disease, Richard Doll and Austin Bradford Hill, initiated the study, and statistician Richard Peto joined the team in 1971. The objective of the study was to assess the risks associated with tobacco use, and its relationship to lung cancer.

Format: Articles

Subject: Experiments

Equilibrium Density Gradient Centrifugation in Cesium Chloride Solutions Developed by Matthew Meselson and Franklin Stahl

Matthew Meselson, Franklin Stahl, and Jerome Vinograd, developed cesium chloride, or CsCl, density gradient centrifugation in the 1950s at the California Institute of Technology, or Caltech, in Pasadena, California. Density gradient centrifugation enables scientists to separate substances based on size, shape, and density. Meselson and Stahl invented a specific type of density gradient centrifugation, called isopycnic centrifugation that used a solution of cesium chloride to separate DNA molecules based on density alone.

Format: Articles

Subject: Technologies

Mammography

Mammography or mastography is an imaging technology used in the twentieth century for the detection of breast cancer and other breast abnormalities. Breast cancer is an abnormal growth in breast tissue that can spread to other parts of the body and cause death. Breast cancer affects about twelve percent of women worldwide. In the twenty-first century, mammography is one of the most accurate tools for screening and diagnosing breast cancer.

Format: Articles

Subject: Technologies

Alec Jeffreys’s Experiments to Identify Individuals by Their Beta-globin Genes (1977-1979)

In a series of experiments in the late 1970s, Alec J. Jeffreys in the UK and Richard A. Flavell in the Netherlands developed a technique to detect variations in the DNA of different individuals. They compared fragments of DNA from individuals’ beta-globin genes, which produce a protein in hemoglobin. Previously, to identify biological material, scientists focused on proteins rather than on genes. But evidence about proteins enabled scientists only to exclude, but not to identify, individuals as the sources of the biological samples.

Format: Articles

Subject: Experiments

Vegas Baby (2016)

In 2016, Runaway Films released the documentary Vegas Baby. The film, directed by Amanda Micheli, follows three women who struggle with infertility problems as they undergo in vitro fertilization, or IVF treatment, to become pregnant. In IVF treatment, a woman’s egg is fertilized by a sperm outside of the woman’s body. Once the sperm fertilizes the egg, a fertility doctor places the fertilized egg back into the woman’s uterus. The three women in the film enter the I Believe contest hosted by the Sher Institute of Reproductive Medicine in Las Vegas, Nevada.

Format: Articles

Subject: Outreach

The First Successful Cloning of a Gaur (2000), by Advanced Cell Technology

The first successful cloning of a gaur in 2000 by Advanced Cell Technology involved the cells of two animals: an egg cell from a domestic cow and a skin cell from a gaur. The researchers extracted the egg cell from the ovary of the domestic cow and the skin cell from the skin of the gaur. First, the researchers performed nuclear transplantation on the egg cell of the cow, during which they removed the nucleus of the egg cell. The mitochondria of the egg cell remained intact inside the cell.

Format: Graphics

Subject: Experiments, Organisms, Reproduction

The Hershey-Chase Experiments (1952), by Alfred Hershey and Martha Chase

In 1951 and 1952, Alfred Hershey and Martha Chase conducted a series of experiments at the Carnegie Institute of Washington in Cold Spring Harbor, New York, that verified genes were made of deoxyribonucleic acid, or DNA. Hershey and Chase performed their experiments, later named the Hershey-Chase experiments, on viruses that infect bacteria, also called bacteriophages. The experiments followed decades of scientists’ skepticism about whether genetic material was composed of protein or DNA.

Format: Articles

Subject: Experiments

Bellotti v. Baird (1979)

On 2 July 1979, the United States Supreme Court decided Bellotti v. Baird, ruling that a Massachusetts law that prohibited minors from obtaining abortions without parental consent was unconstitutional. That law prohibited minors from receiving abortions without permission from both of their parents or a superior court judge. Under that law, if one or both of the minor’s parents denied consent, the minor could petition a superior court judge who would determine whether the minor was competent enough to make the decision to abort on her own.

Format: Articles

Subject: Legal

Sex in a Cold Climate (1998)

In 1998, Testimony Films released the documentary Sex in a Cold Climate, which reported the true stories of four survivors from the Magdalene asylums in Ireland in the twentieth century. Magdalene asylums, also called Magdalene laundries and homes, were institutions of the Catholic Church that sought to reform women engaged in prostitution and those who birthed children out of wedlock by forcing the women to do hard labor.

Format: Articles

Subject: Outreach, Publications

NovaSure Endometrial Ablation

NovaSure is a device for endometrial ablation, which is a procedure that removes the endometrium, that the US Food and Drug Administration, or FDA, approved for use on 28 September 2001. Endometrium is the tissue that lines the uterus. NovaSure destroys the endometrium by sending electric beams at the endometrium. Hologic, a medical technology company concerned with women’s health, developed NovaSure to treat menorrhagia, or heavy bleeding during menstruation. Menorrhagia is a common symptom of endometriosis. Endometriosis is the growth of the endometrium outside of the uterus.

Format: Articles

Subject: Technologies

She’s Beautiful When She’s Angry (2014) by Mary Dore

In 2014, Mary Dore directed the documentary 'She’s Beautiful When She’s Angry,' which details the events and accomplishments of the women’s liberation movement from 1966 to the early 1970s in the United States. The film features commentaries from more than thirty activists who worked to advance the women’s movement. Throughout the film, the activists describe the timeline of events that led to women’s improved access to reproductive healthcare and a reduction in sexual discrimination in the US.

Format: Articles

Subject: Publications

Sperm Capacitation

The male body, followed by male reproductive organs from which the sperm originates, is depicted from top to bottom at the left. Under the male reproductive organs is a diagram of a single sperm. To the right of the sperm diagram, the physiological and morphological changes a sperm undergoes to fertilize an egg are depicted from left to right. Each change is associated with a light pink rectangle background. Each light pink rectangle corresponds to the location of the sperm within the female reproductive organs, which is depicted above it.

Format: Graphics

Subject: Theories, Processes

The Excommunication of Margaret McBride (2009–2010)

In 2010, the Catholic Church excommunicated Margaret McBride, a nun and ethics board member at St. Joseph’s Hospital and Medical Center in Phoenix, Arizona. McBride was excommunicated latae sententiae, or automatically, for approving a therapeutic abortion, which is an abortion that is required to save a pregnant woman’s life. McBride approved an abortion for a woman who was twenty-seven years old, eleven weeks pregnant with her fifth child, and suffered from pulmonary hypertension, a life-threatening condition during pregnancy. Following McBride’s decision, St.

Format: Articles

Subject: Ethics

First American Birth Control Clinic (The Brownsville Clinic), 1916

On 16 October 1916, Margaret Sanger opened one of the first birth control clinics in the United States in Brooklyn, New York, which some have called the Brownsville Clinic. Located at 46 Amboy Street, the clinic was a place where Sanger and her staff verbally communicated with women seeking information about birth control. During the early 1900s, both birth control and abortion were illegal in the US, and publication or circulation of information on both topics was deemed obscene and illegal by the federal Comstock Act.

Format: Articles

Subject: Organizations

Categorization of Conservative, Semi-Conservative, and Dispersive DNA Replication Theories (1953–1956)

In 1956, Gunther Stent, a scientist at the University of California Berkeley in Berkeley, California, coined the terms conservative, semi-conservative, and dispersive to categorize the prevailing theories about how DNA replicated. Stent presented a paper with Max Delbrück titled “On the Mechanism of DNA Replication” at the McCollum-Pratt Symposium at Johns Hopkins University in Baltimore, Maryland. In response to James Watson and Francis Crick’s proposed structure of DNA in 1953, scientists debated how DNA replicated.

Format: Articles

Subject: Theories

“Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid” (1953), by James Watson and Francis Crick

In April 1953, James Watson and Francis Crick published “Molecular Structure of Nucleic Acids: A Structure of Deoxyribose Nucleic Acid” or “A Structure for Deoxyribose Nucleic Acid,” in the journal Nature. In the article, Watson and Crick propose a novel structure for deoxyribonucleic acid or DNA. In 1944, Oswald T. Avery and his group at Rockefeller University in New York City, New York published experimental evidence that DNA contained genes, the biological factors called genes that dictate how organisms grow and develop.

Format: Articles

Subject: Publications

Leuprorelin as a Treatment for Endometriosis

Leuprolide acetate, or leuprorelin, is a manufactured drug that has been prescribed as a treatment for endometriosis, a medical condition in which body tissue that typically lines the uterus grows outside of the uterus, since 1989. Leuprorelin is a modified version of a gonadotropin-releasing hormone, a type of hormone that helps regulate the female menstrual cycle. The drug inhibits the production of estrogen, a female sex hormone that enables endometrial gland growth.

Format: Articles

Subject: Processes

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

“Molecular Configuration in Sodium Thymonucleate” (1953), by Rosalind Franklin and Raymond Gosling

In April 1953, Rosalind Franklin and Raymond Gosling, published “Molecular Configuration in Sodium Thymonucleate,” in the scientific journal Nature. The article contained Franklin and Gosling’s analysis of their X-ray diffraction pattern of thymonucleate or deoxyribonucleic acid, known as DNA. In the early 1950s, scientists confirmed that genes, the heritable factors that control how organisms develop, contained DNA. However, at the time scientists had not determined how DNA functioned or its three-dimensional structure.

Format: Articles

Subject: Publications

United States v. Milan Vuitch (1971)

In the 1971 court case United States v. Milan Vuitch, hereafter US v. Vuitch, the US Supreme Court ruled that a Washington, DC law was constitutional by overturning a 1969 district court decision. Beginning in the early twentieth century, Washington, DC, prohibited abortions except for abortions performed to preserve the life or health of the pregnant woman. In 1969, Milan Vuitch, a physician in Washington, DC, was convicted of criminal abortion for providing an abortion when the woman’s life was not endangered.

Format: Articles

Subject: Legal

“Genetical Implications of the Structure of Deoxyribonucleic Acid” (1953), by James Watson and Francis Crick

In May 1953, scientists James Watson and Francis Crick wrote the article “Genetical Implications of the Structure of Deoxyribonucleic Acid,” hereafter “Genetical Implications,” which was published in the journal Nature.

Format: Articles

Subject: Publications