An empirical investigation of tax practitioners' decisions under uncertainty : a prospect theory approach

Sanders UMI 1990 국내박사

Food security and hunger among low income US households: Relations to federal food assistance program participation

Sanders, Rebecca Elizabeth Portland State University 2007 해외공개박사

This dissertation describes the conceptual and empirical framework that guides the definition of food insecurity and hunger, the present status of federal programmatic responses, and the status of current research on the topic. It also examines relations between hunger and federal food assistance program participation. Logistic regression is utilized to build two predictor models. Model 1 predicts federal food assistance program participation from household structure, income, community characteristics, and demographics. Model 2 predicts food insecurity/hunger from household structure, income, community characteristics, demographics, and federal food assistance program participation. Results are based on 2004 Current Population Survey data from low income households. Model 1 performed better than a constant only model, and reliably distinguished between federal food assistance program participating and non-participating households. As a whole, Model 1 explained approximately 30 percent of the variance in program participation. Household size was the strongest predictor of federal food assistance program participation. Model 2 also performed better than a constant only model, and reliably distinguished between food secure and food insecure/hungry households. As a whole, Model 2 explained less than 10 percent of the variance in food insecurity. Household earnings were the strongest predictor of food insecurity. The odds of food insecurity for households that participated in federal food assistance programs were higher than for households that did not participate. Methodological, philosophical, and policy implications of these findings are discussed. Particular emphasis is placed on the relevance of findings for the field of social work. Suggestions for future research are also provided.

Tau prion strains in cells, mice, and patients

Sanders, David Winland Washington University in St. Louis 2016 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Prion-like propagation of tau aggregation may underlie the stereotyped progression of pathology along neuronal networks in neurodegenerative tauopathies such as Alzheimer's disease. It has become increasingly clear that unique conformations ("strains") of prion protein (PrP) link aggregate structure to clinical phenotypes in human prion diseases. Intriguingly, vast phenotypic diversity in pathological and clinical presentation is also observed in tauopathies. The mechanisms that account for this phenotypic diversity are completely unknown. During my dissertation work, I put forward and tested the hypothesis that distinct tau amyloid conformations (or "strains") are responsible for unique tauopathies. First, I found that in experimental models, tau acts as a prion, replicating distinct strains in vitro and in vivo. I observed that tau indefinitely propagates distinct amyloid conformations in a clonal fashion in cell culture. In collaborative work, I found that two tau strains induce distinct pathologies in vivo as determined by successive inoculations into three generations of transgenic mice. Remarkably, tau from these mice re-created the original strains upon re-introduction to cultured cells. Second, I created a panel of tau prion strains, which have remarkably divergent biochemical and cell biology properties and cause unique patterns of pathology and rates of progression in vivo. Finally, I used my cell system to isolate tau strains from 29 patients with 5 different tauopathies, finding that different diseases are associated with distinct strains. Tau thus demonstrates essential characteristics of a prion. This likely accounts for the phenotypic diversity of tauopathies and could enable more effective diagnosis and therapy.

Intramolecular Singlet Fission in Acenes

Sanders, Samuel Nathan Columbia University ProQuest Dissertations & These 2018 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

In 2017, 98 gigawatts of solar capacity were added globally, outpacing new contributions from coal, gas and nuclear plants combined, based on 161 billion dollars of investment. Solar is the leading contributor to the clean energy revolution and. Within this context, enhancing the power conversion efficiency of solar cells is crucial economically and environmentally. Because sunlight is incident on the earth as a broad spectrum of different colors, the energy of the photons spans a wide. In Chapter 1, we introduce the photophysical process of singlet exciton fission and give an overview of the field, with a focus on its potential for incorporation into photovoltaic devices. In Chapter 2-8, we discuss our results realizing single. Chapter 5 discusses the synthesis and photophysics of homoconjugated and non-conjugated pentacene dimers, where singlet fission occurs through sigma bonds. Again, transient absorption spectroscopy is crucial to the assignment of the photophysics.

The dynamics of parent-school communication, collaboration, and African American students' success: A participatory action research study

Sanders, David Adam Fielding Graduate Institute 2002 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

The purpose of this study was to answer the question, “What needs to be in place to increase collaboration and communication between home and school, which would ultimately facilitate success for African American students?”. The ultimate goal was to provide a course of action to increase collaboration and communication between home and Smart Middle School (a pseudonym), a southeastern metropolitan school in the United States. Numerous studies attest to the fact that communication and collaboration between home and school are absolutely necessary in order to bring about high levels of academic achievement for African American middle school students (Comer, 1993; Epstein, 1995; Foster-Harrison, 1995; Hamilton & Osborne 1994; Robinson & Fine, 1994). The study used a participatory action research process with parents, students, and staff. The participants in the Action Research Study Group (ARSG) utilized the following components of participatory action research: problem, investigation, action, and evaluation (Park, 1999). The Action Research Study Group designed a survey to determine which activities parents would be willing to perform. This was the initial strategy to increase collaboration and communication between home and school. The consensus of the group was that the greater the parental involvement in the school, the greater the communication and collaboration. With increased parental involvement, communication, and collaboration, academic success for all students attending Smart Middle School could be better facilitated, especially for African American students. The survey would be used to recruit other parents to form a parent leadership group. As a result, the parent leadership group, along with school personnel, would then take charge of their situations and implement the strategies revealed by the study to increase collaboration and communication between home and school. Consensus was that the recommended strategies revealed by the ARSG could only be accomplished by utilizing a systemic approach, which includes getting all stakeholders working together as a unit.

The Economics of Retail Food Waste

Sanders, Robert ProQuest Dissertations & Theses The University of 2018 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Each year, the perishable grocery industry produces substantial waste, resulting in considerable costs to firms and generating harmful greenhouse gas emissions. I study the incentives to produce such waste using a novel data set that matches a l.

Arcuate patterning as a central feature on ventral midbrain development during early embryogenesis

Sanders, Timothy Andrew The University of Chicago 2001 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

The vertebrate nervous system develops into a complex, diverse array of neuronal assemblies, termed nuclei, which have characteristic cellular and physiological properties. However, the cellular and molecular mechanisms that generate the neuronal and nuclear and diversity within the brain remain largely unresolved. To address this question of neuronal and nuclear patterning, the embryological organization of the developing ventral midbrain, a principal division of the vertebrate brain, has been examined with respect to its underlying molecular anatomy. Acetylcholinesterase histochemistry and gene expression profiles for homeodomain transcription factors clearly demonstrate that the tegmentum of the embryonic chick is transiently organized as a series of longitudinal columns of differentiated neurons, termed midbrain arcs. Moreover, neuronal phenotypes, cholinergic, dopaminergic and GABAergic neurons, originate in distinct arcuate domains within ventral midbrain suggesting that midbrain arcs are intimately involved in neuronal and subsequent nuclear patterning. This arcuate organization appears to be generated and subsequently maintained by the establishment of longitudinal domains within the population of neuronal progenitors. These longitudinal domains differ with respect to their cell proliferation kinetics as well as repertoire of expressed neural determination factors potentially establishing select populations of precursors specified to particular nuclear fates. From the examination of the temporal-spatial expression profiles of select signaling molecules indicates, it is proposed that the early coordination of BMP and Sonic hedgehog signaling and subsequent WNT signaling results in the initial formation of dorsoventral arrayed longitudinal domains within the ventricular layer. Therefore, the initial establishment of discrete positional values within arcuately oriented progenitor populations establishes the eventual neuronal and nuclear organization of the vertebrate ventral midbrain. The remarkable organization of ventral midbrain into longitudinal, arcuate territories indicates that it will provide an ideal model system to address the mechanisms responsible for neuronal and nuclear patterning in the vertebrate brain.

First-Principles Calculations on the Electronic and Optical Properties of Polar Functional Materials

Sanders, Nocona ProQuest Dissertations & Theses University of Mich 2021 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Regulation of the c-Myc/Max/Mad network during liver development and regeneration

Sanders, Jennifer Ann Brown University 2005 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

The c-myc proto-oncogene has been assigned roles in cellular proliferation, growth, metabolism, apoptosis, and differentiation. c-Myc is considered to be an extremely short-lived protein whose expression is tightly regulated in many cell types. This protein is normally expressed at high levels in proliferating cells and at diminishing levels as cells undergo growth arrest and differentiation. All of the biological activities of c-Myc require its binding partner, Max. c-Myc/Max heterodimers bind DNA at E boxes to either activate or repress transcription of target genes. In contrast to c-Myc, Max is considered to have ubiquitous expression and to be highly stable, resulting in Max levels that under usual conditions exceed those of c-Myc. Max interactions are promiscuous, as Max also dimerizes to another short-lived family of proteins, Mad. The mad family of transcription factors oppose the biological activities of c-Myc by competing for binding to Max and repressing the transcription of a subset of c-Myc activated genes. In contrast to c-Myc, Mad members are expressed during growth arrest and in differentiated cells. In the current model for the c-myc/ max/mad network, Max is constitutively expressed while the transcriptional activity of the network relies upon the differential expression patterns of c-Myc and Mad. The work presented here demonstrates that the currently accepted model of c-myc versus mad expression does not account for the regulation of the c-Myc/Max/Mad network in adult liver. c-Myc protein content was similar in proliferating fetal and quiescent adult liver. However, c-Myc was localized almost exclusively to the nucleolus in adult hepatocytes. max RNA and protein levels were regulated during liver development and its expression correlated with hepatocyte proliferation. Decreases in Max abundance in the adult liver also correlated with c-Myc localization to the nucleolus. This work suggests that the decrease in Max abundance and nucleolar localization of c-Myc may restrict the functional activity of c-Myc in the adult liver.

Self-administered treatment for irritable bowel syndrome: Comparison to a wait list control group

Sanders, Kathryn A State University of New York at Albany 2005 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Self-help treatments for a variety of mental and physical health problems are commercially available; however many of these have not been empirically tested. The purpose of this study was to examine the effectiveness of a self-managed treatment for irritable bowel syndrome (IBS) in comparison to a wait list control. Treatment consisted of an already-published self-help book: Breaking the bonds of irritable bowel syndrome. Participants monitored their gastrointestinal (GI) symptoms for 2 weeks and completed questionnaires measuring psychological symptoms (Brief Symptom Inventory) and quality of life (QOL; IBS Quality of Life) prior to being assigned to either immediate treatment or a wait list condition. Participants assigned to the wait list were crossed over to the treatment condition. Of 33 participants initially recruited 7 completed immediate treatment, 9 the wait list. A further 4 of 9 wait list participants went on to complete the treatment. Analyses revealed the treatment book significantly decreased composite GI symptom scores in comparison to the wait list, but did not lead to significantly larger improvements in QOL or other psychological symptoms. When examining the entire treated sample, analyses showed significant improvement in abdominal pain, average GI symptoms, and QOL after treatment. Despite the small sample size and high drop out rate (43%) in this study, it is an important first step in researching and empirically validating low-cost, self-administered treatments for IBS.