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7. Semiclassical Gravity in the Far Field Limit of Stars, Black Holes, and Wormholes

Author

Carlson, Eric D., Anderson, Paul R., Fabbri, Alessandro, Fagnocchi, Serena, Hirsch, William H., and Klyap, Sarah A.

Subjects
General Relativity and Quantum Cosmology, High Energy Physics - Theory
Abstract

Semiclassical gravity is investigated in a large class of asymptotically flat, static, spherically symmetric spacetimes including those containing static stars, black holes, and wormholes. Specifically the stress-energy tensors of massless free spin 0 and spin 1/2 fields are computed to leading order in the asymptotic regions of these spacetimes. This is done for spin 0 fields in Schwarzschild spacetime using a WKB approximation. It is done numerically for the spin 1/2 field in Schwarzschild, extreme Reissner-Nordstrom, and various wormhole spacetimes. And it is done by finding analytic solutions to the leading order mode equations in a large class of asymptotically flat static spherically symmetric spacetimes. Agreement is shown between these various computational methods. It is found that for all of the spacetimes considered, the energy density and pressure in the asymptotic region are proportional to 1/r^5 to leading order. Furthermore, for the spin 1/2 field and the conformally coupled scalar field, the stress-energy tensor depends only on the leading order geometry in the far field limit. This is also true for the minimally coupled scalar field for spacetimes containing either a static star or a black hole, but not for spacetimes containing a wormhole., Comment: 43 pages, 2 figures. Reference added, minor changes, PRD version

Published
2010
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12. Stress-Energy Tensor for the Massless Spin 1/2 Field in Static Black Hole Spacetimes

Author

Carlson, Eric D., Hirsch, William H., Obermayer, Benedikt, Anderson, Paul R., and Groves, Peter B.

Subjects
General Relativity and Quantum Cosmology, High Energy Physics - Theory
Abstract

The stress-energy tensor for the massless spin 1/2 field is numerically computed outside and on the event horizons of both charged and uncharged static non-rotating black holes, corresponding to the Schwarzschild, Reissner-Nordstrom and extreme Reissner-Nordstr\"om solutions of Einstein's equations. The field is assumed to be in a thermal state at the black hole temperature. Comparison is made between the numerical results and previous analytic approximations for the stress-energy tensor in these spacetimes. For the Schwarzschild (charge zero) solution, it is shown that the stress-energy differs even in sign from the analytic approximation. For the Reissner-Nordstrom and extreme Reissner-Nordstrom solutions, divergences predicted by the analytic approximations are shown not to exist., Comment: 5 pages, 4 figures, additional discussion

Published
2003
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17. ENDOSCOPIC ULTRASOUND-GUIDED GASTROJEJUNOSTOMY IS EFFECTIVE AS A SINGLE PALLIATIVE INTERVENTION FOR PATIENTS WITH GASTRIC OUTLET OBSTRUCTION

Author

Shinn, Brianna, primary, Hirsch, William, additional, Kahaleh, Michel, additional, Shahid, Haroon M., additional, Sarkar, Avik, additional, Tyberg, Amy, additional, Duarte-Chavez, Rodrigo, additional, Kalahasti, Srikaran, additional, Kumta, Nikhil A., additional, DiMaio, Christopher J., additional, Thakkar, Shyam, additional, Shah-Khan, Sardar M., additional, Singh, Shailendra, additional, Piraka, Cyrus, additional, Zuchelli, Tobias, additional, Ichkhanian, Yervant, additional, Nimri, Faisal M., additional, Cosgrove, Natalie D., additional, Kushnir, Vladimir, additional, Genere, Juan Reyes, additional, Mullady, Daniel, additional, Boortalary, Tina, additional, Agnihotri, Abhishek, additional, Kumar, Anand, additional, Chiang, Austin, additional, Schlachterman, Alexander, additional, Loren, David E., additional, and Kowalski, Thomas E., additional

Published
2022
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18. COMPREHENSIVE ANALYSIS OF ADVERSE EVENTS ASSOCIATED WITH TRANSMURAL USE OF LUMEN APPOSING METAL STENTS (LAMS) IN CIRRHOTIC PATIENTS: AN INTERNATIONAL MULTICENTER STUDY

Author

Ichkhanian, Yervant, primary, Ashraf, Taha, additional, Nimri, Faisal M., additional, Shamaa, Omar, additional, Shinn, Brianna, additional, Hirsch, William, additional, Smaltz, Christa, additional, Kowalski, Thomas E., additional, Loren, David E., additional, Kumar, Anand, additional, Schlachterman, Alex, additional, Tantau, Alina, additional, Arevalo-Mora, Martha, additional, Khashab, Mouen A., additional, Singla, Sumit, additional, Simmer, Stephen G., additional, Piraka, Cyrus, additional, and Zuchelli, Tobias, additional

Published
2022
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19. Multi-temporal Pacific madrone leaf blight assessment with unoccupied aircraft systems.

Author

Barker, Matthew I., Burnett, Jonathan D., Haddad, Tanya, Hirsch, William, Dae Kun Kang, Pawlak-Kjolhaug, Kale'a, and Wing, Michael G.

Subjects
LEAF spots, FOREST monitoring, FOREST health, MACHINE learning, LANDSAT satellites, CLIMATE change
Abstract

Pacific madrone leaf blight (PMLB) is a contributing agent to the decline of Pacific madrone (Arbutus menziesii) trees. Multiple fungal pathogens cause PMLB, resulting in leaf spotting that can eventually kill leaves, increasing stress in individuals, and leaving them more susceptible to deadly cankers. Spores transmit via air and water droplets, particularly during wet Spring months. Unoccupied aircraft systems (UAS) technologies are in their relative infancy, but UAS are becoming more affordable and accessible. UAS promise increased efficiency in forest health monitoring applications, providing a safer aerial data collection method at a relatively-low cost when compared to occupied aircraft. In this study, we develop and present a UAS methodology to detect PMLB with a multispectral sensor. This methodology combines orthomosaic products derived from high-resolution (~4 cm) multirotor platform UAS multispectral imagery with machine learning and ground assessment of PMLB to classify visual presence of blight at the individual treelevel during multiple site revisits. The resulting model detected PMLB infection status of 29 field surveyed madrone trees with a kappa coefficient of, a balanced accuracy of 0.85, and a true positive rate of 0.92. The method presented here can be readily scaled to efficiently cover a much larger extent with a beyond-line-of-site capable UAS and minimal field sampling. The increased efficiency of this approach may be critical to characterizing PMLB in the near future as it is anticipated that PMLB prevalence will continue to increase as a result of climate change. [ABSTRACT FROM AUTHOR]

Published
2023
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20. Educational Work of the Young Men's Christian Association. Bulletin, 1923, No. 7

Author

Department of the Interior, Bureau of Education (ED) and Hirsch, William F.

Abstract

The Young Men's Christian Association (Y.M.C.A.) was one of the pioneers in the development of evening education for employed men and boys. The beginnings of this work go back more than half a century, the first work of this kind being reported in 1866. During the last decade of the nineteenth century, broad foundations were laid for the future development of the associations' educational work. In addition to the classes in elementary school and high school subjects, elementary courses in commercial subjects were developed. Later, trade and technical work was added, along with some experimentation in manual training. During the first 15 years of the new century, there came a period of rapid expansion, both in the number of students and in the range of subjects taught. The progress in educational work made by the Y.M.C.A. during the past three years is most gratifying. Not only have the numbers of students and schools increased in considerable proportions, but the advance in the quality of education and in the comprehensiveness of courses and curriculum has also been noteworthy. But, on the other hand, those responsible for the development of this movement feel that only the preliminary steps have been taken toward the attainment of the ultimate goal, which is the perfection of a continental, standardized, Christian character building program of education designed to provide opportunities for the development of young men in every part of the national domain. Topics covered in this bulletin include the following: (1) The educational council; (2) The student body; (3) The field and objectives of the work; (4) Standard courses of study; (5) Publication of textbooks; (6) Instruction material; (7) Examinations and credits; (8) Types of association schools; (9) Building real educational institutions; (10) Correspondence instruction; (11) Educational assistance for ex-service men; and (12) Americanization work. (Contains 1 footnote.) [Best copy available has been provided.]

Published
1923

25. HUE BETTER PAY ATTENTION: THE COLORS IN YOUR HOME MATTER MORE THAN YOU THINK

Author

Hirsch, William

Subjects
Wages and salaries, Salary, Business, general, Business
Abstract

Pablo Picasso said, 'Colors, like features, follow the changes of the emotions.' This is well-known among artists, designers, advertisers and even psychologists. Certain colors trigger predictable emotional responses and have [...]

Published
2020

26. Pituitary stalk and ectopic hyperintense T(sub 1) signal on magnetic resonance imaging: implications for anterior pituitary dysfunction

Author

Ultmann, Michelle C., Siegel, Selma F., Hirsch, William L., Finegold, David N., and Foley, Thomas P., Jr.

Subjects
Magnetic resonance imaging, Hypopituitarism -- Physiological aspects, Pituitary gland -- Physiological aspects, Family and marriage, Health
Abstract

Objective. - To determine if improved delineation of hypothalamic-pituitary neuroanatomy by magnetic resonance imaging, especially the posterior pituitary hyperintense [T.sub.1] signal, can be correlated with anterior and posterior pituitary endocrine function. Design. - Children with ectopic posterior pituitary tissue were identified at the Endocrine Clinic of the Children's Hospital of Pittsburgh (Pa) and their records were reviewed. Participants. - Ten children with ectopic posterior pituitary tissue. Measurements. - Anterior pituitary hormone status, determined by standard testing, was correlated with the morphologic anomalies of the hypothalamic-pituitary region on magnetic resonance imaging. Results. - Patients were categorized by the appearance of the pituitary stalk based on the magnetic resonance image: attenuation of the stalk (group 1) or nonvisualization of the stalk (group 2). Patients in group 1 retained partial anterior pituitary function. Patients in group 2 had panhypopituitarism. Conclusion. - Prospective evaluation of affected individuals may provide insight into the pathophysiologic mechanisms of idiopathic hypopituitarism. (AJDC. 1993;147:647-652), The use of magnetic resonance imaging (MRI) is leading to increased knowledge about the relationship between structural abnormalities of the hypothalamus and pituitary gland and various growth disorders. Generally, for individuals not suffering from hypopituitarism, a bright signal from the posterior pituitary gland is seen in only one location on MRI films. However, in patients with insufficient anterior pituitary function, the signal is located outside the area where it is normally seen. Absence or attenuation of the pituitary stalk seems to be associated with different aspects of pituitary hormone deficiencies. Retrospective analysis of MRI scans of children suffering from growth disorders may lead to a better understanding of the pathology of hypopituitarism.

Published
1993

30. Pelvic Floor Symptom Related Distress in Chronic Constipation Correlates With a Diagnosis of Irritable Bowel Syndrome With Constipation and Constipation Severity but Not Pelvic Floor Dyssynergia

Author

Singh, Prashant, primary, Seo, Yoonjin, additional, Ballou, Sarah, additional, Ludwig, Andrew, additional, Hirsch, William, additional, Rangan, Vikram, additional, Iturrino, Johanna, additional, Lembo, Anthony, additional, and Nee, Judy W, additional

Published
2019
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32. Significant Morbidity and Mortality Associated with Fecal Impaction in Patients Who Present to the Emergency Department

Author

Sommers, Thomas, primary, Petersen, Travis, additional, Singh, Prashant, additional, Rangan, Vikram, additional, Hirsch, William, additional, Katon, Jesse, additional, Ballou, Sarah, additional, Cheng, Vivian, additional, Friedlander, Daniel, additional, Nee, Judy, additional, Lembo, Anthony, additional, and Iturrino, Johanna, additional

Published
2018
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38. Su1857 - Emergency Department Utilization for Inflammatory Bowel Disease from 2006-2014

Author

Ballou, Sarah, primary, Hirsch, William, additional, Singh, Prashant, additional, Rangan, Vikram, additional, Nee, Judy, additional, Iturrino-Moreda, Johanna, additional, Sommers, Thomas, additional, Zubiago, Julia, additional, Sengupta, Neil, additional, Bollom, Andrea, additional, Jones, Michael P., additional, Moss, Alan C., additional, Flier, Sarah N., additional, Cheifetz, Adam S., additional, and Lembo, Anthony J., additional

Published
2018
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42. Bob Cole

Author

Hirsch, William

Published
1941

44. Correlative angiographic and pathologic findings in the diagnosis of ulcerated plaques in the carotid artery

Author

Estol, Conrado, Claassen, Diana, Hirsch, William, Wechsler, Lawrence, and Moossy, John

Subjects
Carotid artery diseases -- Diagnosis, Diagnosis, Radioscopic -- Research, Angiography -- Research, Health
Abstract

Atherosclerosis in the carotid artery is regarded as an important risk factor for stroke. One possible mechanism is that an ulcerated plaque provides a point for blood clots to form; these blood clots may break off, travel into the brain to block smaller arteries supplying regions of the brain. This hypothesis remains controversial because it has been difficult to obtain objective supportive data. Adding to this difficulty is the fact that it is hard to determine whether or not an atherosclerotic plaque in the carotid artery is ulcerated; as a result, studies differ widely in their assessment of ulceration as a risk factor for thrombosis (clot formation) and subsequent stroke. A study was undertaken to compare the findings obtained by imaging of the internal carotid artery using angiography with the definitive identification of ulceration by pathological examination of specimens removed after surgery. The results of the study of 36 arterial specimens, 18 of which proved to be ulcerated regions upon microscopic examination, confirmed that diagnoses made on the basis of angiographic images are not particularly accurate. Only 56 percent of the ulcerated plaques were identified on the basis of angiography, and 89 percent of the plaques identified as ulcerated were confirmed upon pathological examination. In addition, the study found that there was little agreement among different observers viewing the same angiogram. When classifying the atherosclerotic lesions into three groups on the basis of ulceration, three observers were in agreement for only 4 percent of the lesions examined. These results indicate that diagnosing atherosclerotic ulceration on the basis of angiography is not reliable. (Consumer Summary produced by Reliance Medical Information, Inc.)

Published
1991

45. Open-label versus double-blind placebo treatment in irritable bowel syndrome: study protocol for a randomized controlled trial

Author

Ballou, Sarah, primary, Kaptchuk, Ted J., additional, Hirsch, William, additional, Nee, Judy, additional, Iturrino, Johanna, additional, Hall, Kathryn T., additional, Kelley, John M., additional, Cheng, Vivian, additional, Kirsch, Irving, additional, Jacobson, Eric, additional, Conboy, Lisa, additional, Lembo, Anthony, additional, and Davis, Roger B., additional

Published
2017
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