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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.
Gestational diabetes is a medical condition that causes blood sugar levels to become abnormally high, which manifests for the first-time during pregnancy and typically disappears immediately after birth for around ninety percent of affected women. While many women with the condition do not experience any noticeable symptoms, some may experience increased thirst and urination.
In 1904, physician William Henry Walling published Sexology, a family medicine reference book. In his book, Walling proposed that his guidance would help people who were married or single and young or old, as well as anyone who wanted to conform to, what he claims are, gender expectations. Sexology discusses issues such as masturbation, abortion, pregnancy, labor, and marriage.
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.
In an experiment later named for them, Matthew Stanley Meselson and Franklin William Stahl in the US demonstrated during the 1950s the semi-conservative replication of DNA, such that each daughter DNA molecule contains one new daughter subunit and one subunit conserved from the parental DNA molecule. The researchers conducted the experiment at California Institute of Technology (Caltech) in Pasadena, California, from October 1957 to January 1958.
“Female Ejaculation: A Case Study” (1981), by Frank Addiego, Edwin G. Belzer Jr., Jill Comolli, William Moger, John D. Perry, and Beverly Whipple
In 1981, Frank Addiego and colleagues published “Female Ejaculation: A Case Study” in The Journal of Sex Research. In the article, the authors find that female ejaculation, or the expulsion of fluid from a female’s urethra during or before orgasm, is a legitimate phenomenon that can occur when one stimulates an area in the vaginal wall that the team names the Gräfenberg-spot. According to the authors, at the time of publication, many individuals believed that if a female expelled fluid during orgasm, the fluid was urine and, thus, improper bladder control caused the expulsions.
The Report of the Committee of Inquiry into Human Fertilisation and Embryology (1984), by Mary Warnock and the Committee of Inquiry into Human Fertilisation and Embryology
The Report of the Committee of Inquiry
into Human Fertilisation and Embryology, commonly called the Warnock
Report after the chair of the committee Mary Warnock, is the 1984
publication of a UK governmental inquiry into the social impacts of
infertility treatment and embryological research. The birth of Louise
Brown in 1978 in Oldham, UK, sparked debate about reproductive and
embryological technologies. Brown was conceived through in vitro
fertilization (IVF), a process of fertilization that occurs outside of
"Altruism and the Origin of the Worker Caste" from The Ants (1990), by Bert Hölldobler and Edward Osborne Wilson
In 'Altruism and the Origin of the Worker Caste,' Bert Hölldobler and Edward Osborne Wilson explore the evolutionary origins of worker ants. 'Altruism and the Origin of the Worker Caste' is the fourth chapter of Hölldobler and Wilson's book, The Ants, which was published by The Belknap Press of Harvard University in Cambridge, Massachusetts, in 1990. In 'Altruism and the Origin of the Worker Caste,' Hölldobler and Wilson evaluate various explanations for how a non-reproductive caste of ant evolved.
In 1830, a dispute erupted in the halls of lÕAcad mie des Sciences in Paris between the two most prominent anatomists of the nineteenth century. Georges Cuvier and tienne Geoffroy Saint-Hilaire, once friends and colleagues at the Paris Museum, became arch rivals after this historical episode. Like many important disputes in the history of science, this debate echoes several points of contrasts between the two thinkers.
Format: Essays and Theses