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Topic Review
Spontaneous Cerebrospinal Fluid Leak
A spontaneous cerebrospinal fluid leak (sCSF leak) is a cerebrospinal fluid leak – a leak of cerebrospinal fluid that surrounds the brain and spinal cord from the protective dural sac for no apparent reason. The dura mater is the tough, outermost of layer of the meninges, the membranes surrounding the brain and spinal cord. A spontaneous CSF leak, arises idiopathically, and is opposed to traumatically caused CSF leaks. It is one of several types of cerebrospinal fluid leaks caused by one or more holes in the dura. A loss of CSF greater than its rate of production leads to a decreased volume inside the skull known as intracranial hypotension. Any CSF leak is most often characterized by orthostatic headaches, which worsen when standing, and improve when lying down. Other symptoms can include neck pain or stiffness, nausea, vomiting, dizziness, fatigue, and a metallic taste in the mouth. A CT scan can identify the site of a cerebrospinal fluid leakage. Once identified, the leak can often be repaired by an epidural blood patch, an injection of the patient's own blood at the site of the leak, a fibrin glue injection, or surgery. The set of symptoms associated with a sCSF leak is referred to as a spontaneous cerebrospinal fluid leak syndrome (SCSFLS). A sCSF leak is rare, affecting five out of every 100,000 people. On average, the condition develops at age 42, and women are twice as likely to be affected. Some people with a sCSF leak have a chronic leak of cerebrospinal fluid despite repeated patching attempts, leading to long-term disability due to pain. SCSFLS was first described by German neurologist Georg Schaltenbrand in 1938 and by American neurologist Henry Woltman of the Mayo Clinic in the 1950s.
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  • 22 Nov 2022
Biography
Georg Stetter
Georg Carl Stetter (23 December 1895 – 14 July 1988) was an Austrian-Germany nuclear physicist. Stetter was Director of the Second Physics Institute of the University of Vienna. He was a principal member of the German nuclear energy project, also known as the Uranium Club. In the latter years of World War II, he was also the Director of the Institute for Neutron Research. After the war, he wa
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  • 09 Dec 2022
Topic Review
Diagnosis Using Urine Samples
Urine is a by-product of kidney metabolism and is rich in many nitrogen-containing substances, including urea, uric acid and creatinine, which are excreted from the body as water-soluble chemicals during urination. The urine volume of normal healthy adults ranges from 0.6 to 2.6 L per day, where approximately 91–96% of this urine is composed of water. However, urine also contains various inorganic salts and organic compounds, such as proteins, hormones, and metabolites. The chemical composition of fresh urine mainly consists of nitrogen, ammonium, ammonia nitrogen, nitrate, nitrite, phosphorus, potassium, sulfate, sodium, magnesium, chloride, and calcium. Moreover, the urine of healthy individuals is clear or light yellow in color. However, in the presence of certain diseases or disorders, such as hematuria, diabetes, or kidney stones, distinct changes in the color, composition or smell of urine may occur. Therefore, urine serves as an important bio-rich resource for health monitoring.
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  • 16 Aug 2021
Biography
Ignace Robert Dautray
Ignace Robert Dautray, born Kouchelevitz on February 1, 1928 in the 10th arrondissement of Paris,[1] is a French engineer, former scientific director of the French Commissariat à l'Energie Atomique (CEA) and former High Commissioner for Atomic Energy. He is a member of the French Academy of Sciences, section mechanical and computer sciences,[2] and of the French Academy of Technology.[3] Bor
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  • 20 Dec 2022
Biography
Henri Abraham
Henri Abraham (1868–1943) was a France physicist who made important contributions to the science of radio waves. He performed some of the first measurements of the propagation velocity of radio waves, helped develop France's first triode vacuum tube, and with Eugene Bloch invented the astable multivibrator.[1] Henri Abraham was born July 12, 1868 in the 1st arrondissement of Paris. After br
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  • 08 Dec 2022
Biography
Harold A. Zahl
Harold Adelbert Zahl (August 24, 1904 – March 11, 1973) was an American physicist who had a 35-year career with the U.S. Army Signal Corps Laboratories, making major contributions to radar development. Harold Zahl was born in Chatsworth, Illinois, the son of an Evangelical minister. While still in high school, he became an amateur radio operator (call letters 6BHI). He graduated in physics
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  • 08 Dec 2022
Biography
Richard M. Osgood Jr.
Richard Magee Osgood Junior (born December 28, 1943 in Kansas City).[1] is an American applied and pure physicist (condensed matter and chemical physics of surfaces, laser technology, nano-optics). He is currently Higgins Professor of Electrical Engineering[2] and Applied Physics[3] at Columbia University. Osgood began his scientific career in 1966, after graduating from the U.S. Military Aca
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  • 09 Dec 2022
Topic Review
Lung Cavity
A lung cavity or pulmonary cavity is an abnormal, thick-walled, air-filled space within the lung. Cavities in the lung can be caused by infections, cancer, autoimmune conditions, trauma, congenital defects, or pulmonary embolism. The most common cause of a single lung cavity is lung cancer. Bacterial, mycobacterial, and fungal infections are common causes of lung cavities. Globally, tuberculosis is likely the most common infectious cause of lung cavities. Less commonly, parasitic infections can cause cavities. Viral infections almost never cause cavities. The terms cavity and cyst are frequently used interchangeably; however, a cavity is thick walled (at least 5 mm), while a cyst is thin walled (4 mm or less). The distinction is important because cystic lesions are unlikely to be cancer, while cavitary lesions are often caused by cancer. Diagnosis of a lung cavity is made with a chest X-ray or CT scan of the chest, which helps to exclude mimics like lung cysts, emphysema, bullae, and cystic bronchiectasis. Once an imaging diagnosis has been made, a person’s symptoms can be used to further narrow the differential diagnosis. For example, recent onset of fever and productive cough suggest an infection, while a chronic cough, fatigue, and unintentional weight loss suggest cancer or tuberculosis. Symptoms of a lung cavity due to infection can include fever, chills, and cough. Knowing how long someone has had symptoms for or how long a cavity has been present on imaging can also help to narrow down the diagnosis. If symptoms or imaging findings have been present for less than three months, the cause is most likely an acute infection; if they have been present for more than three months, the cause is most likely a chronic infection, cancer, or an autoimmune disease. The presence of lung cavities is associated with worse outcomes in lung cancer and tuberculosis; however, if a lung cancer develops cavitation after chemotherapy and radiofrequency ablation, that indicates a good response to treatment.
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  • 06 Oct 2022
Topic Review
Salanoia durrelli
Salanoia durrelli, also known as Durrell's vontsira, is a Madagascar mammal in the family Eupleridae of the order Carnivora. It is most closely related to the brown-tailed mongoose (Salanoia concolor), with which it forms the genus Salanoia. The two are genetically similar, but morphologically distinct, leading scientists to recognize them as separate species. After an individual was observed in 2004, the animal became known to science and S. durrelli was described as a new species in 2010. It is found only in the Lac Alaotra area. A small, reddish-brown carnivore, Salanoia durrelli is characterized by broad feet with prominent pads, reddish-buff underparts, and broad, robust teeth, among other differences from the brown-tailed mongoose. In the only two weighed specimens, body mass was 600 and 675 g (21.2 and 23.8 oz). It is a marsh-dwelling animal that may feed on crustaceans and mollusks. The Lac Alaotra area is a threatened ecosystem, and S. durrelli may also be endangered by competition with introduced species.
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  • 10 Oct 2022
Biography
Zinaida Ershova
Zinaida Vasil'evna Ershova (also Yershova) (Russian: Ершова Зинаида Васильевна) (23 October 1904 — 25 April 1995) was a Russian chemist, physicist and engineer. She spent her entire career working with radioactive elements and headed laboratories producing radioactive materials used mostly in the Soviet atomic bomb project and the Soviet space programme. She was born
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  • 08 Dec 2022
Biography
Robley D. Evans
Robley Dunglison Evans (May 18, 1907, University Place, Nebraska – December 31, 1995, Paradise Valley, Arizona) was an American nuclear physicist and pioneer of nuclear medicine. He was the president of the Health Physics Society in 1972–1973.[1] His father Manley Jefferson Evans (1878–1970) and mother Alice Jennie Turner (1882–1965) married in August 1905 in O'Neill, Nebraska. Manley
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  • 14 Dec 2022
Biography
Wilmot N. Hess
Wilmot N. Hess (October 16, 1926 – April 16, 2004) was an American physicist who was involved with many ambitious scientific projects of the 20th century, including: the Plowshares project, the NASA Apollo moon missions, the National Oceanic and Atmospheric Administration (NOAA) hurricane research and oil spill cleanup research, the National Center for Atmospheric Research (NCAR) weather modif
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  • 29 Dec 2022
Biography
Georg Joos
Georg Jakob Christof Joos (25 May 1894 in Bad Urach, German Empire – 20 May 1959 in Munich, West Germany) was a German experimental physicist. He wrote Lehrbuch der theoretischen Physik, first published in 1932 and one of the most influential theoretical physics textbooks of the 20th Century. Joos began his higher education in 1912 at the Technische Hochschule Stuttgart. He then went to stu
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  • 12 Dec 2022
Biography
William R. Blair
William Richards Blair (November 7, 1874 – September 2, 1962) was an American scientist and U.S. Army officer, who worked on the development of the radar in United States starting during the 1930s. He led the U.S. Army's Signal Corps Laboratories during its formative years and is often called the "Father of American Radar".[1] Blair was born in Ireland in County Londonderry on November 7, 1
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  • 22 Nov 2022
Biography
Martin Pope
Martin Pope (born August 22, 1918) is a physical chemist and professor emeritus at New York University. His discoveries of ohmic contacts and research in the fields of organic insulators and semiconductors led to techniques enabling organic semiconductors to carry relatively large currents, and to convert electricity into light and vice versa. These discoveries have had application in electroph
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  • 15 Dec 2022
Biography
Herbert Mataré
Herbert Franz Mataré (22 September 1912 – 2 September 2011[1]) was a Germany physicist. The focus of his research was the field of semiconductor research. His best-known work is the first functional "European" transistor, which he developed and patented together with Heinrich Welker in the vicinity of Paris in 1948, at the same time and independently from the Bell Labs engineers. The final 20
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  • 12 Dec 2022
Topic Review
Hydrogen Peroxide and Dental Environment
Hydrogen peroxide is an effective biocide in its gaseous (vaporized and aerosolized) form against viruses, spores, fungi, and bacteria. The vaporized solution of hydrogen peroxide, which is based on water, is activated by plasma and acts as an oxidizing and disinfecting agent when it settles and contacts the surfaces of all objects in the room.
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  • 12 May 2021
Biography
Tullio Regge
Tullio Eugenio Regge (July 11, 1931 – October 23, 2014) was an Italian theoretical physicist.[1] Regge obtained the laurea in physics from the University of Turin in 1952 under the direction of Mario Verde and Gleb Wataghin, and a Ph.D. in physics from the University of Rochester in 1957 under the direction of Robert Marshak. From 1958 to 1959 Regge held a post at the Max Planck Institute f
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  • 18 Nov 2022
Topic Review
Proteomic Landscape of Ovarian Cancer
Ovarian cancer (OC) is often used as an umbrella term referring to malignancies caused by ovarian epithelial inclusion cysts that are trapped beneath the surface of the epithelium of the ovary as well as malignancies in the peritoneum and fallopian tube.
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  • 17 Jun 2021
Topic Review
Danaus (Genus)
Danaus, commonly called tigers, milkweeds, monarchs, wanderers, and queens, is a genus of butterflies in the tiger butterfly tribe. They are found worldwide, including North America, South America, Africa, Asia, Indonesia and Australia . For other tigers see the genus, Parantica.
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  • 19 Oct 2022
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