Phased array feed design technology for Large Aperture Microwave Radiometer (LAMR) Earth observations

An assessment of the potential and limitations of phased array antennas in space-based geophysical precision radiometry is described. Mathematical models exhibiting the dependence of system and scene temperatures and system sensitivity on phased array antenna parameters and components such as phase shifters and low noise amplifiers (LNA) are developed. Emphasis is given to minimum noise temperature designs wherein the LNA's are located at the array level, one per element or subarray. Two types of combiners are considered: array lenses (space feeds) and corporate networks. The result of a survey of suitable components and devices is described. The data obtained from that survey are used in conjunction with the mathematical models to yield an assessment of effective array antenna noise temperature for representative geostationary and low Earth orbit systems. Practical methods of calibrating a space-based, phased array radiometer are briefly addressed as well

Febrile Convulsions in Families

In a well-studied community of 3,953 individuals under 20 years of age, 142 or 3.6 per cent had a history of one or more proven febrile seizures. Certain families are more FC-prone. An unexpectedly strong relationship was found between children with febrile convulsions and sibs with mental retardation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68040/2/10.1177_000992286600501007.pd

Analysis of the effects of baffles on combustion instability

An analytical model has been developed for predicting the effects of baffles on combustion instability. This model has been developed by coupling an acoustic analysis of the wave motion within baffled chambers with a model for the oscillatory combustion response of a propellant droplet developed by Heidmann. A computer program was developed for numerical solution of the resultant coupled equations. Diagnostic calculations were made to determine the reasons for the improper prediction. These calculations showed that the chosen method of representing the combustion response was a very poor approximation. At the end of the program, attempts were made to minimize this effect but the model still improperly predicts the stability trends. Therefore, it is recommended that additional analysis be done with an improved approximation

Skateboard Injuries in a Campus Community

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67018/2/10.1177_000992286700600421.pd

Patterns of urban heat-wave deaths and implications for prevention: Data from New York and St. Louis during July, 1966

Patterns of urban heat wave deaths in New York and St. Louis during July 1966 indicate not only the impact of environmental stress on heat-susceptible segments of the population but provide clues to the possible prevention of such deaths. While mortality from all causes increased by 36% in New York and by 56% in St. Louis certain subgroups were at substantially higher risk (persons over age 65; censustract residents with low income, crowding, or poor housing; those with hypertensive, arteriosclerotic, cardiovascular, or other circulatory disease, diabetes, or chronic respiratory disease). The oppressiveness of heat waves in cities is emphasized by increased rates of homicide and by clashes with police in the streets. On the brighter side, pediatric deaths were controlled during heat episodes in both cities, suggesting that medical, social, and environmental measures can intervene.Unless the general approach to urban heat waves becomes prospective rather than retrospective, one can anticipate episodes of excess mortality during the summers of the 1970's with a human cost of about 136 excess deaths per million per week of heat stress.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34139/1/0000423.pd

Febrile Convulsions as a Problem in Waiting Times

A simple hypothesis on the occurrence of febrile convulsions is posed. This is (1) that certain children are genetically predisposed, and (2) that for such children, the probability of the first attack occurring in year 1, 2, etc., is essentially constant up to the end of the period during which the attacks can take place. These assumptions lead to a probability model which agrees well with data on age at first attack in the Town of Tecumseh, Mich. It appears that susceptibility does not gradually diminish, but rather disappears abruptly. The calculation yields an estimate of the proportion of children, among those susceptible, who will have at least one attack before they exceed the age of suceptibility. Penetrance of the condition, measured in this way, is nearly complete: 93.8% will have manifested the condition by age 7. The population frequency of the susceptible type of child is found to be 3.90%. If one assumes the simple dominant mode of inheritance of Frantzen et al. to be correct, this estimate of population frequency leads to an estimate of the gene frequency. This is approximately p = 0.02. The homozygote would therefore have a frequency of 4 per 10,000. Some speculations on verifying this theory of inheritance by identifying the homozygote are given. RÉSUMÉ On Émet une hypothÈse simple sur la survenue des convulsions fÉbriles, À savoir (1) que certains enfants sont gÉnÉtiquement prÉdisposÉs et (2) que pour ces enfants la probabilitÉ d'apparition de la premiÈre crise dans la premiÈre, la seconde annÉe, etc. est essentiellement constante jusqu'À la fin de la pÉriode pendant laquelle les crises peuvent survenir. De telles suppositions conduisent ÀÉtablir un modÈle de probabilite qui concorde bien avec les donnÉes sur l'Âge de la premiÈre crise, dans la ville de Techumseh, dans le Michigan. Il en ressort que cette prÉdisposition ne diminue pas progressivement, mais au contraire, disparaÎt brusquement. Les calculs permettent d'estimer la proportion d'enfants prÉdisposÉs qui auront au moins une crise, avant d'avoir dÉpassÉ l'Âge limite de la prÉdisposition. La pÉnÉtrance de cette condition, ainsi ÉvaluÉe, est presque complÈte: 93.8% des enfants auront manifestÉ cette condition À l'Âge de 7 ans. La frÉquence des enfants prÉdisposÉs dans la population est de 3.90%. Si l'on considÈre que le mode d'hÉrÉditÉ dominante simple de Frantzen est valable, cette estimation de la frÉquence dans la population conduit À une Évaluation de la frÉquence du gÈne. Celle-ci est approximativement de p = 0.02; l'homozygote aurait done une frÉquence de 4/10.000. Les possibilitÉs de vÉrifier cette thÉorie des modalitÉs hÉrÉditaires par l'identification de l'homozygote sont discutÉes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65705/1/j.1528-1157.1972.tb05265.x.pd

Endoscopic Retrograde Cholangiopancreatography at Henry Ford Hospital: 1972-1977

Between 7972 and /977, 440 patients underwent endoscopic retrograde cholangiopancreatography (FRCP) at Henry Ford Hospital. The procedure was found to be most useful for identifying the site and nature of an extrahepatic obstruction, the diagnosis of pancreatic cancer, and the preoperative evaluation of chronic pancreatitis. One death occurred as a result of cholangitis in a patient with cancer of the pancreas. Review of the data has led us to refine our indications for FRCP. It has been shown to be a valuable technique with a low incidence of complications in evaluating pancreaticobiliary disease. Based on our study, it would be indicated for jaundiced patients without dilated ducts by echogram or with failure of or contraindication to percutaneous transhepatic cholangiography (PTC), carefully selected patients with unexplained abdominal pain, preoperative evaluation of patients with chronic pancreatitis, and in patients with presumed primary biliary cirrhosis

Scanning Electron Microscopy of the Surface of Human Duodenum in Patients With and Without Duodenal Ulcer Disease

Endoscopic biopsy specimens of normal human duodenum from patients with duodenal ulcer disease were studied by light microscopy and by scanning electron microscopy. For scanning, the tissue was dried by the critical point-drying technique. SEM criteria for both normal and abnormal duodenal surfaces were determined. SEM evidence for the presence of tuft cells similar to those found on the surface of rat duodenum was found in both the normal and abnormal human material. Although other reports have described the favorable effects of carbenoxolone sodium treatment on duodenal ulcer disease, our SEM studies of four patients found that this treatment had no effect on the duodenal surface