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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
591

A blink of Harvard Business School’s program “Certificate of Management Excellence”: - and takeaways for the work of a Chief Compliance Officer in an international environment

Quella, Jérôme-Oliver 03 November 2022 (has links)
The following blink reflects the personal experiences and takeaways made by the author during a selected program at Harvard Business School during March 2022 to August 2022. It is neither intended to pretend, assert, or even assume that similar experiences are not possible in applicable universities or learning institutions at any other place nor is the author financially bonded of either receiving gratuities or benefits of some kind to/from Harvard Business and/or Law School. Therefore, the blink is an aftermath of the specific experience in an extraordinary divers and professional learning environment that has been.
592

An examination of factors affecting the acceptance of innovative social studies curriculum materials

Farmer, Charles E., Saye, John W., January 2008 (has links) (PDF)
Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 262-279).
593

Stellar Works: Searching for the Lives of Women in Science

Woodman, Jennifer Elizabeth 07 June 2016 (has links)
While women have had a profound impact in the world of science, they struggle to gain an equal foothold in many science, technology, engineering, and mathematics (STEM) fields today. This has led to considerable public and private sector efforts to recruit women into these arenas. In order to understand how schools and nonprofits engage today's young women in STEM studies, this account includes time spent both in high school science classrooms and with ChickTech -- a Portland-based organization that works to provide a pathway into tech careers for high school-aged girls. A historical perspective reveals that modern women aren't treading into completely uncharted territory, in spite of the current disparity of representation in today's STEM arenas. This perspective is offered via an examination of the lives of a group of extraordinary women who worked in astronomy at Harvard College Observatory from the late 1800s into the 1960s. While several noteworthy women are discussed, the focus here is on Cecilia Payne, the first person to earn a Ph.D. in astronomy at Harvard, and one of the 20th century's greatest astronomers. A great many people have never heard of her . . . yet.
594

Carbon and nitrogen distribution and processes in forest and agricultural ecosystems: a study involving solid- and liquid-state NMR and pyrolysis GC/MS

Dria, Karl Jay 17 June 2004 (has links)
No description available.
595

MODERNIZATION OF THE MOCK CIRCULATORY LOOP: ADVANCED PHYSICAL MODELING, HIGH PERFORMANCE HARDWARE, AND INCORPORATION OF ANATOMICAL MODELS

Taylor, Charles 09 May 2013 (has links)
A systemic mock circulatory loop plays a pivotal role as the in vitro assessment tool for left heart medical devices. The standard design employed by many research groups dates to the early 1970's, and lacks the acuity needed for the advanced device designs currently being explored. The necessity to update the architecture of this in vitro tool has become apparent as the historical design fails to deliver the performance needed to simulate conditions and events that have been clinically identified as challenges for future device designs. In order to appropriately deliver the testing solution needed, a comprehensive evaluation of the functionality demanded must be understood. The resulting system is a fully automated systemic mock circulatory loop, inclusive of anatomical geometries at critical flow sections, and accompanying software tools to execute precise investigations of cardiac device performance. Delivering this complete testing solution will be achieved through three research aims: (1) Utilization of advanced physical modeling tools to develop a high fidelity computational model of the in vitro system. This model will enable control design of the logic that will govern the in vitro actuators, allow experimental settings to be evaluated prior to execution in the mock circulatory loop, and determination of system settings that replicate clinical patient data. (2) Deployment of a fully automated mock circulatory loop that allows for runtime control of all the settings needed to appropriately construct the conditions of interest. It is essential that the system is able to change set point on the fly; simulation of cardiovascular dynamics and event sequences require this functionality. The robustness of an automated system with incorporated closed loop control logic yields a mock circulatory loop with excellent reproducibility, which is essential for effective device evaluation. (3) Incorporating anatomical geometry at the critical device interfaces; ascending aorta and left atrium. These anatomies represent complex shapes; the flows present in these sections are complex and greatly affect device performance. Increasing the fidelity of the local flow fields at these interfaces delivers a more accurate representation of the device performance in vivo.
596

The drug development process : evaluation of PDUFA I/II and investigation into reducing drug development times / Evaluation of PDUFA I/II and investigation into reducing drug development times

Strobeck, Matthew W. (Matthew William), 1972- January 2004 (has links)
Thesis (S.M.)--Harvard-MIT Division of Health Sciences and Technology; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2004. / Includes bibliographical references (p. 59-61). / Published findings report that it takes approximately eight years to bring a novel drug to market at an average cost of $800 million. Over the last ten years, the Food and Drug Administration (FDA) has helped to reduce the time from filing a new drug application (NDA) to granting marketing approval (i.e. the approval phase). However, there has been no alteration in the time required to progress from an investigational new drug application (IND) to an NDA filing (i.e. the clinical phase) over this same period. Since approval times began to decrease upon the initiation of the Prescription Drug User Fee Act (PDUFA), in this thesis I analyze the impact of PDUFA and calculate its benefits to companies. Due to the importance of getting new drugs to the market faster, I also investigate why there has been no significant change in the time required to test a drug clinically, and attempt to identify steps that could be taken to improve the clinical trial process. To investigate this, I evaluated ways in which the FDA and industry can work together to reduce clinical development times, without compromising safety. The results from this study show that PDUFA has had a significant impact on reducing approval times. More importantly, I determined that the direct costs of PDUFA are small in irmlparison to its benefits. In addition, my analysis of the early clinical phases (pre-clinical to Phase II) of drug benefits. In addition, my analysis of the early clinical phases (pre-clinical to Phase II) of drug development has revealed potential steps both the FDA and industry can take to facilitate a more efficient process for assessing the safety and efficacy of drugs. Thus, this study represents an important step towards improving the development of medicines for the world. / by Matthew W. Strobeck. / S.M.
597

The use of thermal diffusivity to quantify tissue perfusion

Valvano, Jonathan Walker January 1981 (has links)
Thesis (Ph.D.)--Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology Program in Medical Engineering and Medical Physics, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE / Vita. / Includes bibliographical references. / by Jonathan Walker Valvano. / Ph.D.
598

Peer influence on smoking : causation or correlation?

Langenskiöld, Sophie January 2005 (has links)
In this thesis, we explore two different approaches to causal inferences. The traditional approach models the theoretical relationship between the outcome variables and their explanatory variables, i.e., the science, at the same time as the systematic differences between treated and control subjects are modeled, i.e., the assignment mechanism. The alternative approach, based on Rubin's Causal Model (RCM), makes it possible to model the science and the assignment mechanism separately in a two-step procedure. In the first step, no outcome variables are used when the assignment mechanism is modeled, the treated students are matched with similar control students using this mechanism, and the models for the science are determined. Outcome variables are only used in the second step when these pre-specified models for the science are fitted. In the first paper, we use the traditional approach to evaluate whether a husband is more prone to quit smoking when his wife quits smoking than he would have been had his wife not quit. We find evidence that this is the case, but that our analysis must rely on restrictive assumptions. In the subsequent two papers, we use the alternative RCM approach to evaluate if a Harvard freshman who does not smoke (observed potential outcome) is more prone to start smoking when he shares a suite with at least one smoker, than he would have been had he shared a suite with only smokers (missing potential outcomes). We do not find evidence that this is the case, and the small and insignificant treatment effect is robust against various assumptions that we make regarding covariate adjustments and missing potential outcomes. In contrast, we do find such evidence when we use the traditional approach previously used in the literature to evaluate peer effects relating to smoking, but the treatment effect is not robust against the assumptions that we make regarding covariate adjustments. These contrasting results in the two latter papers allow us to conclude that there are a number of advantages with the alternative RCM approach over the traditional approaches previously used to evaluate peer effects relating to smoking. Because the RCM does not use the outcome variables when the assignment mechanism is modeled, it can be re-fit repeatedly without biasing the models for the science. The assignment mechanism can then often be modeled to fit the data better and, because the models for the science can consequently better control for the assignment mechanism, they can be fit with less restrictive assumptions. Moreover, because the RCM models two distinct processes separately, the implications of the assumptions that are made on these processes become more transparent. Finally, the RCM can derive the two potential outcomes needed for drawing causal inferences explicitly, which enhances the transparency of the assumptions made with regard to the missing potential outcomes. / Diss. Stockholm : Handelshögskolan, 2006 S. 1-13: sammanfattning, s. [15]-161: 4 uppsatser
599

An inquiry into the general purposes, functions, and organization of selected university schools of education with special reference to certain aspects of their growth and development,

O'Leary, Timothy Francis, January 1941 (has links)
Thesis (Ph. D.)--Catholic University of America, 1941. / Bibliography: p. 415-426.
600

An?lise e caracteriza??o do material particulado atmosf?rico fino em uma regi?o metropolitana de Natal-RN / Analysis and characterization of atmospheric fine particulate matter at a location in the metropolitan region of Natal-RN

Duarte, Edicl? de Souza Fernandes 28 June 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-22T18:59:34Z No. of bitstreams: 1 EdicleDeSouzaFernandesDuarte_DISSERT.pdf: 4138983 bytes, checksum: df01c5170db549f67ecd82cd96196064 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-06T18:52:40Z (GMT) No. of bitstreams: 1 EdicleDeSouzaFernandesDuarte_DISSERT.pdf: 4138983 bytes, checksum: df01c5170db549f67ecd82cd96196064 (MD5) / Made available in DSpace on 2017-03-06T18:52:40Z (GMT). No. of bitstreams: 1 EdicleDeSouzaFernandesDuarte_DISSERT.pdf: 4138983 bytes, checksum: df01c5170db549f67ecd82cd96196064 (MD5) Previous issue date: 2016-06-28 / Este trabalho teve como objetivo elaborar uma caracteriza??o qu?mica de aeross?is atmosf?ricos s?lidos finos (MP2.5) coletados por um Impactador Harvard na cidade de Natal, capital do estado do Rio Grande do Norte, Brasil. A amostragem foi feita diariamente, utilizando filtros de quartzo de 37 mm. Utilizaram-se t?cnicas de gravimetria, quantifica??o de Black Carbon (BC) e an?lise de Fluoresc?ncia de Raio-X para a an?lise destes filtros. A amostragem de MP2.5 ocorreu de forma cont?nua no per?odo de 03 de mar?o de 2015 a 31 de Dezembro de 2015. Tamb?m foram feitas simula??es de dispers?o e deposi??o deste material particulado usando o modelo de trajet?rias HYSPLIT com o objetivo de identificar a origem e o destino desses poluentes na atmosfera. Os resultados mostram que as concentra??es de massa m?dias mensais variaram de 2,98 a 14,43 ?g/m3 para o MP2.5 no per?odo analisado. J? as concentra??es m?dias di?rias de MP2.5 variaram de 0,25 a 62,79 ?g/m3 no mesmo per?odo. As an?lises de BC mostraram que o m?s de junho apresentou o maior pico de concentra??o de 3,42 ?g/m?. Atrav?s da an?lise de concentra??o do BC para os dias da semana foi poss?vel observar nos gr?ficos box plot que as concentra??es no s?bado e domingo tendem a ser menores que nos demais dias da semana, isto pode estar associado ao efeito da diminui??o do tr?fego de ve?culos nestes dias. Os dias de semana, de segunda a sexta-feira, apresentaram as maiores dispers?es de valores de concentra??o de BC em que o intervalo interquartil foi superior aos dias de s?bado e domingo, mostrando que as concentra??es de BC s?o maiores durante a semana do que nos finais de semana tendo em vista que o tr?fego de ve?culos ? mais intenso. A partir das coletas obtidas pelo amostrador de particulado fino e an?lise por Fluoresc?ncia de Raio-X (EDX) foi poss?vel identificar os elementos com maior concentra??o presentes nos filtros: o S, K, Si, Al, Cl, Fe, P, Ca, Mn e Ca. A maioria dos componentes ? de origem antropog?nica de acordo com o fator de enriquecimento, sendo Na, Mg, Sn, Zn, Al, Fe e Ti proveniente de fontes naturais. Os resultados das concentra??es de MP2.5 foram relacionados estatisticamente com vari?veis meteorol?gicas para obter informa??es sobre os efeitos dessas vari?veis sobre a concentra??o de MP. / This study had as objective a chemical characterization of PM 2.5 aerosol collected by a Harvard Sampler in Natal, capital of the state of Rio Grande do Norte, Brazil. Sampling was performed daily using a 37 mm quartz filters. Gravimetric techniques were used, as well as quantification of Black Carbon (BC), and X-ray fluorescence analysis. Also, simulations were made to understand dispersion and deposition of the particulate matter using trajectories of the HYSPLIT model in order to know the origin and fate of these pollutants in the atmosphere. The sampling of PM2.5 occurred continuously for the period from March 03, 2015 to December 2015. The results showed that the monthly averages ranged from 2.98 a 14.43 ?g/m3 for the analyzed PM2.5 period, while the daily average concentrations ranged from 0.25 a 62,79 ?g/m3 for PM 2.5 during the same period. The BC analysis showed that the month of June showed the highest peak of BC concentration of approximately 3.42 ?g/m3. Through the BC concentration analysis by weekdays it was observed in the box plot graphs that the concentrations on Saturday and Sunday tend to be smaller than the other days of the week. This can be associated with the effect of the reduction in vehicle traffic during these days. The days from Monday through Friday, showed the highest dispersion of BC concentrations in which the interquartile range was greater than the days of Saturday and Sunday, showing that BC concentrations are larger during the week than on weekends since vehicle traffic is more intense. From the samples obtained by the fine particulate sampler and analysis by X-ray fluorescence (EDX) it was possible to identify the elements with the highest concentration present in the filters: S, K, Si, Al, Cl, Fe, P, Ca, Mn and Ca. Most of these components were of anthropogenic origin according to the enrichment factor, and Na, Mg, Sn, Zn, Al, Fe and Ti are from natural sources. The results of PM2.5 concentrations were statistically related to meteorological variables for information about the effects of these variables on the concentration.

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