Journey back home : Self, place and remembering among residents in long-term care settings

Chaudhury, Habib Numan The University of Winconsin - Madison 2001 국내박사

Multi-tasking and the returns to experience

Chaudhury, Parama New York University 2003 해외박사(DDOD)

This dissertation is a contribution to the study of the causes and patterns of wage inequality in the United States. In particular, I document how later cohorts of workers—workers who have entered the labor market more recently—have a steeper experience-wage profile, and I present a theory based on the choice of jobs that explains this phenomenon. I show that the trend towards more multi-tasking and less specialization within the firm has resulted in greater returns to experience. If a job consists of a number of tasks which are good substitutes and the returns to experience in each task fall with the level of experience in that task, then jobs with more tasks will have steeper experience-wage profiles. Technical progress—a fall in the time required per task—induces each new cohort to choose jobs with more tasks, as long as the tasks are sufficiently substitutable, and those already working may also move to jobs with more tasks. Using both the Panel Study of Income Dynamics and the Current Population Survey, I provide evidence of the fact that successive cohorts have greater returns to experience. Next, I construct proxies for multi-tasking using Paul Osterman's 1992 survey of workplace practices in a random sample of U.S. establishments, and find that (i) later cohorts choose jobs with greater multi-tasking, (ii) the rate of within job wage growth rises with the degree of multi-tasking, and (iii) the returns to experience are larger in jobs with more multi-tasking. These returns persist even when I take into account the fact that there is sorting into jobs based on unobserved individual heterogeneity, and that job choice is endogenous.

Journey back home: Self, place and remembering among residents in long-term care settings

Chaudhury, Habib Numan The University of Wisconsin - Milwaukee 2001 해외박사(DDOD)

The premise of this exploratory study lies in the inescapable fact that human experience occurs within the context of place. Places, especially personally meaningful ones, may serve as mnemonic anchors in autobiographical recollections, even for the cognitively impaired, and be a means of recalling who we are. A conceptual framework with recollection of past places as an ongoing dialogue between “I” and “Me” guided the empirical study. Recollection of the personal past is considered as a creative and dynamic process. This study explored the following interrelated research questions: (a) What are the emergent themes in recollection of past places for cognitively intact residents in long-term care settings? (b) Is place recollected by cognitively impaired residents? (c) What are the dimensions of place recollection by cognitively impaired residents? (d) Can place-related prompts trigger recollection of past places by cognitively impaired residents? (e) What are the differences in recollection of places in cognitively intact and impaired residents? (f) Can art be a medium for place-based recollection for cognitively impaired residents? and (g) What is the value of cognitively impaired residents' place-biosketches for staff in long-term care facilities?. This study draws on interviews with eight cognitively intact residents, fifteen family members of residents with dementia, and thirteen residents with dementia. All residents were living in four nursing homes in Milwaukee, Wisconsin. Generic questions exploring past places, e.g., homes, neighborhoods, schools, etc. were used in interviews with cognitively intact residents and family members; place-related biographical information and personal and generic photographs were used as prompts in conversations with cognitively impaired residents. Art as a medium of place-based recollection was explored for cognitively impaired residents. Conclusions of the study include: (a) place experiences were recollected by all cognitively intact residents; (b) recollections of places were embedded within broader lived experiences; (c) verbal and visual prompts were effective in triggering recollections in residents with dementia; (d) personal visual prompts were more effective than generic visual prompts; (e) childhood place experiences were more frequently and vividly recollected than adulthood memories by residents with dementia; and (f) place-based recollection can serve as an avenue for maintaining and/or re-establishing a sense of self.

Improved Techniques for Cardiovascular Flow Experiments

Chaudhury, Rafeed Ahmed Arizona State University 2015 해외박사(DDOD)

Aortic pathologies such as coarctation, dissection, and aneurysm represent a particularly emergent class of cardiovascular diseases and account for significant cardiovascular morbidity and mortality worldwide. Computational simulations of aortic flows are growing increasingly important as tools for gaining understanding of these pathologies and for planning their surgical repair. In vitro experiments are required to validate these simulations against real world data, and a pulsatile flow pump system can provide physiologic flow conditions characteristic of the aorta. This dissertation presents improved experimental techniques for in vitro aortic blood flow and the increasingly larger parts of the human cardiovascular system. Specifically, this work develops new flow management and measurement techniques for cardiovascular flow experiments with the aim to improve clinical evaluation and treatment planning of aortic diseases. The hypothesis of this research is that transient flow driven by a step change in volume flux in a piston-based pulsatile flow pump system behaves differently from transient flow driven by a step change in pressure gradient, the development time being substantially reduced in the former. Due to this difference in behavior, the response to a piston-driven pump can be predicted in order to establish inlet velocity and flow waveforms at a downstream phantom model. The main objectives of this dissertation were: 1) to design, construct, and validate a piston-based flow pump system for aortic flow experiments, 2) to characterize temporal and spatial development of start-up flows driven by a piston pump that produces a step change from zero flow to a constant volume flux in realistic (finite) tube geometries for physiologic Reynolds numbers, and 3) to develop a method to predict downstream velocity and flow waveforms at the inlet of an aortic phantom model and determine the input waveform needed to achieve the intended waveform at the test section. Application of these newly improved flow management tools and measurement techniques were then demonstrated through in vitro experiments in patient-specific coarctation of aorta flow phantom models manufactured in-house and compared to computational simulations to inform and execute future experiments and simulations.

Efficiency and productivity of Nepalese agriculture

Chaudhury, Nazmul Michigan State University 2001 해외박사(DDOD)

In the first chapter, a stochastic production frontier framework is used to examine the technical efficiency of rice production for a sample of irrigated farmers in the Rupandehi district of Nepal. Coefficient estimates from the production frontier indicate that: (a) source of irrigation and varietal choice are the two most important factors which enhance rice yields; (b) mid-season water stress and long term non-use of organic fertilizer, are the two primary factors which adversely effect rice yields. Farm level technical efficiency measures derived from the production frontier model, suggests that on average, rice yields could have potentially been increased by slightly over half a metric ton per hectare, corresponding to a 18% average increase in output, via a more efficient utilization of available resources at the current state of technology. I then explore for the relationship between technical efficiency and two sets of variables: (1) farmers's grasp of agronomic principles and knowledge; (2) socio-economic environment in which the farmer operates. I am particularly interested in examining how education and land ownership size is related to efficiency, two specific issues which have received considerable attention in the literature. I find a significant relationship between secondary education and efficiency. Average technical inefficiency in rice production is reduced by 16% in plots farmed by households in which the primary farm manager has completed more than five years of schooling. I also find a significant inverted U-shaped relation between technical inefficiency and land ownership size (i.e., a significant U-shaped efficiency-size relationship). However, the significance of this efficiency-size relationship appears to be sensitive to model specification/endogeneity bias. In the second chapter, a stochastic production frontier approach embedded in a metaproduction function framework is used to: (a) estimate the district level rates of technical change in Nepalese agriculture based upon econometric estimation of the underlying production technology; (b) derive point estimates of district level technical efficiency from parametric estimation of the production technology; and (c) given that I am interested in comparing efficiency levels across districts, I also construct confidence intervals around the time varying technical efficiency estimates, using non-parametric bootstrap methods. When literacy is included in the analysis, there appears to be no significant growth in TFP in the Terai region, while there appears to be a severe decline in TFP growth in the Hill region. Significant negative TFP growth rates in the Hill region might reflect a pernicious decline in the quantity/quality of the natural resource base, however, it is not possible to explicitly examine the interplay between natural resource degradation and agricultural productivity given the data available for this study. This study also highlights the fact that there exists substantial scope for increasing output via a better utilization of existing inputs and technologies in the Terai region. For example, agricultural output in 1991 could have been increased by 40% in the Terai region via a more efficient utilization of existing inputs and technologies. There also exists tremendous potential for increasing output in the all region, however, this potential is perhaps being squandered due to natural resource degradation.

Attitudes towards the Diagnosis and Treatment of Depression among South Asian Muslim Americans

Chaudhury, Sadia Rahman Columbia University 2011 해외박사(DDOD)

While Muslim Americans are one of the fastest growing communities in the United States, very little is known about their mental health needs or concerns. In an effort to better understand their mental health needs, this study explores the attitudes towards the diagnosis and treatment of depression among South Asian Muslim Americans, specifically examining how acculturation shapes these attitudes. A sample of 427 South Asian Muslim Americans (mean age 30.67 years, 73.8% female) completed an anonymous survey on the internet. Participants answered questions about how strongly they agreed with certain diagnostic and treatment recommendations after reading two clinical vignettes, and completed the Attitudes towards Seeking Professional Psychological Help Scale and the Acculturation Rating Scale for Mexican-Americans II. Participants were also asked about their personal experiences with depression, religious identity; and demographic information. Results indicated that educated participants were more accepting of a clinical diagnosis of depression, while females and educated participants had more positive attitudes towards seeking professional psychological help for depression. Acculturation predicted more positive attitudes toward seeking professional psychological help for depression, but did not predict acceptance of a clinical diagnosis of depression, comfort level talking to people outside the family, likelihood of seeking professional help, or importance of ethnic match with mental health provider. Exploratory analyses were conducted to determine how personal history of depression shapes attitudes; however, this variable was not particularly salient in shaping attitudes in this sample. While the results suggest that acculturation did not play as strong a role in predicting attitudes as initially anticipated, several limitations, including the fact that the instrument used to measure acculturation and enculturation in this study has not been validated in this sample and that the sample may be more acculturated than the general South Asian Muslim American population, must be taken into consideration. The results of this study begin to shed light on the attitudes towards depression and its treatment in this community. Future studies should further explore the roles of acculturation and enculturation, while also collecting more personal qualitative information to more fully understand the experiences and needs of South Asian Muslim Americans.

Identification of chitinase as a novel virulence factor for Listeria monocytogenes

Chaudhuri, Swarnava University of Illinois at Chicago 2011 해외박사(DDOD)

<italic>Listeria monocytogenes</italic> is a food borne Gram positive pathogen that causes the disease listeriosis in humans and animals. <italic> L. monocytogenes</italic> has been the responsible for a number of food-borne outbreaks of listeriosis among humans. The disease caused by this bacterium can become very severe in immunocompromised people, often resulting in deaths. <italic>L. monocytogenes</italic> is ubiquitious in nature, and is found in diverse ecological niches such as soil, water and natural vegetation. However, when this free living bacterium enters a mammalian host it often causes disease, and is therefore regarded as an environmental pathogen. Environmental pathogens are those microorganisms that spend substantial parts of their life cycles outside their hosts, but can cause disease when they are inside the host. An important question about environmental pathogens is whether they are able to use molecules that are required for their survival outside the host, as virulence factors when they are inside their hosts. This hypothesis has come into the focus with the emergence of chitinases and chitin binding proteins as virulence factors in two other environmental pathogens, <italic> Legionella pneumophila</italic> and <italic>Vibrio cholerae.</italic> Chitinases are enzymes that hydrolyze chitin, which is a linear polymer of N-acetylglucosamine residues linked by (β1, 4) glycosidic bonds. Chitin is present in cell walls of algae and fungi; and in the exoskeletons of insects, mollusks, crustaceans and is the second most abundant organic compound on the earth. Bacterial chitinases and chitin binding proteins are supposed to be used for nutrient acquisition by utilizing chitin as a readily available source of carbon and nitrogen. However, with the works done on <italic>L. pneumophila</italic> and <italic> V. cholerae,</italic> it is evident that these pathogenic bacteria use chitinases and chitin binding proteins to enhance their survival in mammalian hosts as well. The goal of this thesis is to find out whether <italic>L. monocytogenes </italic> uses its chitinase and chitin binding proteins for its survival inside animal models of infection. The thesis has two main parts. The first part will examine whether mutant strains of <italic>L. monocytogenes</italic> lacking chitinase and/or chitin binding proteins are attenuated in in vitro and in vivo models of infection. The second part of the thesis will examine the probable mechanisms by which chitinases of <italic>L. monocytogenes </italic> can be used by the bacterium to enhance its survival in the host.

The Relationship between Training Outsourcing and Organizational Commitment

Chaudhuri, Sanghamitra University of Minnesota 2011 해외박사(DDOD)

The human resource practice of training outsourcing is emerging as one of the fastest-growing segments of the broader business process outsourcing industry. In spite of its growing popularity in both academic literature and professional practice, training outsourcing is continuously subjected to critical reviews and on-going debates regarding the decision to 'outsource' or 'not to outsource'. There exists, however, a paucity of research on training outsourcing as a human resource development (HRD) practice on different organizational outcomes. This dissertation is an exploratory study that attempted to build on and extend previous research that examined the relationship between training and organizational commitment by focusing on outsourced training. This study also fills an important gap in the training outsourcing literature by taking into consideration employee perceptions and preferences towards outsourced training. The study is framed by social exchange theory to explore possible relationships between training outsourcing and organizational commitment. The respondents from this study were employees from two software consulting organizations based in the U.S. and India. A total of 246 completed and usable surveys were collected for a response rate of 33.9%. Descriptive statistics, bivariate correlation, and moderated multiple regression were used for analyzing the data. The results showed that perceptions of quality, usefulness and relevance, customization, and supervisory support towards outsourced training were positively related to organizational commitment. Supervisory support towards outsourced training was the strongest predictor explaining 20% of the unique variance in organizational commitment. It was also found that the type of training outsourced, general skills or firm-specific skills, did not moderate the relationship between different aspect of training outsourcing and organizational commitment. However, it was noteworthy that 61% of the employees stated that they had preference towards the source of receiving training. Based on the finding a series of recommendations are made for the effective management of training outsourcing. Moreover, recommendations for HRD scholars and practitioners are also made. The overall positive association between training outsourcing and organizational commitment provides a strong business justification to HRD directors and managers for making additional investments in outsourced training.

Topological Bounds on Certain Open Subvarieties of the compactfied Moduli Space of Curves

Chaudhuri, Chitrabhanu Northwestern University 2013 해외박사(DDOD)

Let M⩽kg⊂M g be the moduli of stable curves with at most k rational components, and H⩽g=Hg ∩M⩽kg . We study the affine stratification number (asn) of H⩽kg . Our main result here is asn H⩽kg ≤ g − 1 + k. Conjecturally this bound holds also for M⩽kg . We then investigate the cohomological excess (ce) of H⩽0g , and show that ce( H⩽0g ) ≥ g − 1. We prove this by demonstrating a natural constructible sheaf on H⩽kg , which has non-vanishing cohomology in the correct degree. Our result in turn shows that the upper bound we showed for asn H⩽kg is sharp when k = 0. Our result also shows that ce( M⩽0g ) ≥ g − 1. The fact that Hg is the quotient of M0,2 g+2 by a symmetric group, is used throughout. We give a technique to relate the strata of M 0,2g+2, to that of Hg. The proof of the main theorem involves analysing a spectral sequence in compactly supported cohomology, which has a natural symmetric group action on it. We study this spectral sequence using the operad structure on the cohomology of M 0,2g+2 and investigating the symmetric group action which yields the result. The associated operads are the gravity and hypercommutative operads which were shown to be Koszul duals of each other in Getzler. We utilise that and give an alternative proof of the fact in this thesis.

Deep Facial Expression Modeling and 3D Motion Retargeting from 2D Images

Chaudhuri, Bindita University of Washington ProQuest Dissertations & 2021 해외박사(DDOD)