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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.
81

Prospective Teachers' Development Of Whole Number Concepts And Operations During A Classroom Teaching Experiment

Roy, George 01 January 2008 (has links)
A classroom teaching experiment was conducted to document prospective teachers' development of whole number concepts and operations. The purpose of this mixed-methods study was to examine the collective understanding of prospective teachers in an elementary mathematics content course. Design research methodology, specifically a classroom teaching experiment was the methodology selected for this study since it allows learning to be documented in a classroom environment and is iterative in nature. A revised hypothetical learning trajectory and instructional tasks from a previous classroom teaching experiment were used in this study (Andreasen, 2006). Research about children's development of whole number concepts and operations was used in developing instructional learning goals. In addition, research regarding prospective teachers' development supported the instructional modification that all tasks would be presented and expected to be reasoned about in base-8. Both qualitative data and quantitative data were collected. Qualitative data included whole class dialogue that was videotaped and transcribed, as well as student work samples. Quantitative data included items from the Content Knowledge for Teaching Mathematics database that were administered prior to and subsequent to the instructional sequence in base-8 (Hill, Schilling, & Ball, 2005). It should be noted that the items selected from the database were in base-10. The emergent perspective served as the interpretive framework of the collected qualitative data. This perspective reflexively coordinates the social or group perspective simultaneously with psychological or individual perspective. As stated, this study sought to describe the communal mathematics understanding of prospective teachers in an elementary mathematics content course. Toulmin's (1969) model of argumentation and Rasmussen and Stephan's three-phase methodology served to document normative ways of group reasoning called classroom mathematical practices. The following classroom mathematical practices were identified as taken-as-shared by prospective teachers: (a) developing small number relationships using Double 10-Frames, (b) developing two-digit thinking strategies using the open number line, (c) flexibly representing equivalent quantities using pictures or Inventory Forms, and (d) developing addition and subtraction strategies using pictures or an Inventory Form. Quantitative results indicated that prospective teachers were able to apply mathematical understandings grounded in base-8 to whole number concepts in base-10. In the end, counting and calculating in base-8 provides a meaningful context for prospective teachers to reconstruct their knowledge of whole number concepts and operations.
82

Genes Encoding Flower- and Root-Specific Functions Are More Resistant to Fractionation Than Globally Expressed Genes in Brassica rapa

Kolkailah, Naiyerah F 01 June 2016 (has links) (PDF)
Like many angiosperms, Brassica rapa underwent several rounds of whole genome duplication during its evolutionary history. Brassica rapa is particularly valuable for studying genome evolution because it also experienced whole genome triplication shortly after it diverged from the common ancestor it shares with Arabidopsis thaliana about 17-20 million years ago. While many B. rapa genes appear resistant to paralog retention, close to 50% of B. rapa genes have retained multiple, paralogous loci for millions of years and appear to be multi-copy tolerant. Based on previous studies, gene function may contribute to the selective pressure driving certain genes back to singleton status. It is suspected that other factors, such as gene expression patterns, also play a role in determining the fate of genes following whole genome triplication. Published RNA-seq data was used to determine if gene expression patterns influence the retention of extra gene copies. It is hypothesized that retention of genes in duplicate and triplicate is more likely if those genes are expressed in a tissue-specific manner, as opposed to being expressed globally across all tissues. This study shows that genes expressed specifically in flowers and roots in B. rapa are more resistant to fractionation than globally expressed genes following whole genome triplication. In particular, there appears to have been selection on genes expressed specifically in flower tissues to retain higher copy numbers and for all three copies to exhibit the same flower-specific expression pattern. Future research to determine if these observations in Brassica rapa are consistent with other angiosperms that have undergone recent whole genome duplication would confirm that retention of flower-specific-expressed genes is a general feature in plant genome evolution and not specific to B. rapa.
83

Validity of the paleolithic diet and its relative effectiveness for overall nutrition

Gregoire, James 22 January 2016 (has links)
The Paleolithic, or ancestral, diet was first proposed by Eaton and Konner in 1985, and it is based on the theory that humans have not diverged greatly from the physiology of the Paleolithic human. Eaton and Konner suggested a diet consisting of meats, fruits, vegetables, nuts and seeds while omitting food such as dairy, grains, legumes, refined sugar and processed foods. The latter of which are incongruous with the diet we evolved with and are likely the cause of the so-called "diseases of civilization" such as type 2 diabetes, coronary heart disease, obesity, osteoporosis and cancer (Konner & Eaton, 2010). This review will first elaborate on the Paleolithic lifestyle and the evidence presented on it before examining the evidence for and against other diet categories not included in the diet such as whole grains, red meat, grass-fed meat, dairy milk and soymilk. The aim of this study is to first evaluate the Paleolithic diet, based on nutrition and ability to address common public health diseases and then to appraise the value of other food categories not included in the lifestyle on the same factors, in order to determine their place in an ideal diet. This study concludes that the Paleolithic diet can lower total body weight, body mass index, cardiovascular risks, triglycerides and low-density lipoprotein among others while increasing insulin sensitivity and ω-3, iron, fiber, vitamins and minerals, including improving the ω-6 to ω-3 ratio and the potassium to sodium ratio when compared to the typical Western diet. The results were consistent even when compared to other diets such as the Mediterranean or the diabetes diet. Studies showing the effectiveness of consuming other foods, such as whole grains, dairy or soymilk, with the intent on losing weight or preventing diabetes, on the other hand, have been inconclusive. Research on soy's estrogenic isoflavone action has been inconclusive. Concerns over the consumption of red meat due to cholesterol and cancer are mitigated and review of the grass-fed literature reveals a potentially richer fatty acid profile with more healthy polyunsaturated fats and less cholesterol-raising saturated fatty acids. It is concluded that an ancestral diet of whole foods, made up of mostly fruits and vegetables, meats, especially grass-fed, nuts and seeds is strongly associated with significantly better outcomes for diseases such as type 2 diabetes and obesity as compared to a typical Western diet, Mediterranean diet or diabetes diet.
84

Characterization and evaluation of heat treated wheat flours

Khamis, Moses January 1900 (has links)
Doctor of Philosophy / Department of Grain Science and Industry / Hulya Dogan / The concept of thermal processing of foodstuffs has been used extensively since 1920 when the first scientific basis for calculating the minimum safe sterilization process was developed. There are several methods used in thermal processing of dry foods including infrared, microwave, hydrothermal treatments such as annealing and heat-moisture treatment, thermomechanical treatments (extrusion), and indirect (hot air) and indirect (steam) heating. Thermal processing has been the most widely used method for preserving and extending the shelf-life (via microbial reduction and enzyme inactivation, and for improving quality and functionality. In 2009 the Centers for Disease Control and Prevention released a report of an Escherichia coli outbreak resulting from consumers eating raw refrigerated cookie dough which brought attention to heat treatment of flours and powders. Chlorination of wheat flour in the European Union countries has been replaced in recent years by heat-treated flour which is used to produce high ratio cakes. By applying heat treatment, it is possible to modify the physical and rheological properties. The primary effect of heat treatment is denaturation of the proteins, partial reduction or inactivation of alpha-amylase, and partial gelatinization of the starch. Understanding of relationship between heat transfer, thermal properties of food, heating medium, thermodynamics and the functionality of the resulting heat-treated flour is of critical importance. Research reported in this dissertation has five chapters. Chapter 1 provides a general overview on the state-of-knowledge in the area. Chapter 2 focuses on developing a thermomechanical treatment (extrusion) for improving the functionality of low quality (ash > 1.3%) wheat flour. Chapter 3 deals with developing a direct, rapid and continuous thermal processing technique for treating whole wheat flour and whole wheat grain, and investigates physicochemical changes of heat-treated samples at various moisture-time-temperature combinations. Chapter 4 explores the mixing and development of composite flours in the presence of gluten fractions of at varying proportions, mixing speed and temperatures. Chapter 5 highlights general conclusions and identifies areas for future research.
85

Factors affecting whole grain consumption: primary focus health factors

Scott, Willie Henry Jr. January 1900 (has links)
Master of Science / Department of Agricultural Economics / John A. Fox / We designed a mail survey to investigate consumer choices between whole-grain and regular grain products. Consumption of whole-grain foods has been linked to numerous health benefits including reduced risk of heart disease, diabetes and obesity. The prevalence of obesity has increased in recent decades and has been shown to be negatively correlated with education levels and income. Data from the survey are used to investigate correlations between the likelihood of choosing whole-grain alternatives and various demographic and behavioral characteristics including an individual's Body Mass Index (BMI). We also investigate the impact on consumer choices of providing information about the health benefits of whole-grain foods. Results indicate that education level and the use of food labels are both positively correlated with the likelihood of choosing whole-grain foods. Provision of information about health benefits also had a positive impact on the likelihood of choosing a whole-grain over a conventional grain product, but given a low sample size in this study the effect was not statistically significant. Choices were found to be largely insensitive to changes in relative prices, and no correlation was found between BMI and the likelihood of choosing a whole-grain product.
86

Genome-wide SNP identification and QTL mapping for black rot resistance in cabbage

Lee, Jonghoon, Izzah, Nur K., Jayakodi, Murukarthick, Perumal, Sampath, Joh, Ho J., Lee, Hyeon J., Lee, Sang-Choon, Park, Jee Y., Yang, Ki-Woung, Nou, Il-Sup, Seo, Joodeok, Yoo, Jaeheung, Suh, Youngdeok, Ahn, Kyounggu, Lee, Ji Hyun, Choi, Gyung Ja, Yu, Yeisoo, Kim, Heebal, Yang, Tae-Jin January 2015 (has links)
BACKGROUND: Black rot is a destructive bacterial disease causing large yield and quality losses in Brassica oleracea. To detect quantitative trait loci (QTL) for black rot resistance, we performed whole-genome resequencing of two cabbage parental lines and genome-wide SNP identification using the recently published B. oleracea genome sequences as reference. RESULTS: Approximately 11.5 Gb of sequencing data was produced from each parental line. Reference genome-guided mapping and SNP calling revealed 674,521 SNPs between the two cabbage lines, with an average of one SNP per 662.5 bp. Among 167 dCAPS markers derived from candidate SNPs, 117 (70.1%) were validated as bona fide SNPs showing polymorphism between the parental lines. We then improved the resolution of a previous genetic map by adding 103 markers including 87 SNP-based dCAPS markers. The new map composed of 368 markers and covers 1467.3 cM with an average interval of 3.88 cM between adjacent markers. We evaluated black rot resistance in the mapping population in three independent inoculation tests using F₂:₃ progenies and identified one major QTL and three minor QTLs. CONCLUSION: We report successful utilization of whole-genome resequencing for large-scale SNP identification and development of molecular markers for genetic map construction. In addition, we identified novel QTLs for black rot resistance. The high-density genetic map will promote QTL analysis for other important agricultural traits and marker-assisted breeding of B. oleracea.
87

Application of deterministic 3D SN transport driven dose kernel methods for out-of-field dose assessments in clinical megavoltage radiation therapy

Huang, Mi 07 January 2016 (has links)
With the recent interest in single fraction Stereotactic Body Radiation Therapy and the emerging prominence of the Rapid Arc radiotherapy technique capable of delivering a fast and accurate treatment, the in-field primary dose and out-of-field dose assessments are becoming increasingly important. Currently, full physics Monte Carlo calculations for dose calculations have been regarded as a ‘gold standard’ for dose assessments of the target and OAR (organ at risk). However, these Monte Carlo calculations require very long computation times. The current treatment planning methods provide shorter calculation times, but issues such as heterogeneities and model-based parameter calculations cause challenges and affect dose calculation accuracy. This thesis describes a new and fast dose estimation method leveraging parallel computing called EDK-SN, “Electron Dose Kernel-Discrete Ordinates”. This new method uses hybrid electron dose kernels driven by linear Boltzmann (discrete ordinates) photon transport method to carry out dose calculations. The method has proven effective for fast and accurate computations of out-of-field whole body dose calculations benchmarked to Monte Carlo with isotropic monoenergetic photon sources. This thesis accomplishes adaptation of clinical Varian phase space data for use with general Monte Carlo codes including MCNP, and mapping accurate phase space data into the application of optimized EDK-SN dose calculation method with a 15-year-old patient phantom. The EDK-SN method with improved source term modeling is demonstrated to fall within accuracy of the measured golden beam data for a clinical water phantom.
88

Chronic Pain Management in a Reservation Border Town

Farrell, Cynthia S. January 2010 (has links)
Pain is a growing national public health problem that contributes to spiraling health care costs and significant societal burden in the United States. It is the most common reason for seeking health care services, and is the leading cause of disability (CDC, 2008). Inadequately treated pain has profound social, psychological, economic, and physiological consequences for patients, their families, and society (American Pain Society, 2009).A community-based participatory research (CBPR) approach was used for this project to develop a knowledge base about issues associated with chronic pain and its treatment among Native American people in Winslow, AZ. Mixed methods (qualitative and quantitative) were used to gain insight into the local factors that contribute to the self-management and treatment of chronic pain.The results of a provider survey indicated that there are negative psychological traits toward patients with chronic pain such as authoritarianism, intolerance of ambiguity, reliance on technology, and locus of control which are factors that are known to negatively influence pain care (Weinstein et al, 2000). Lack of knowledge regarding pain and pain management along with perceptions and fears related to drug regulatory agencies were additional factors that were found, constituting additional barriers. Patient participants were generally dissatisfied with the pain care practices at Winslow Indian Health. Patient reported treatment goals that included relief of pain, improved quality of life, the ability to return to work, the ability to perform household chores, and the ability to participate in more physical leisure activities.This results of this practice inquiry indicate there is a disconnect between patient and provider views and expectations around pain treatment and the need for further studies to determine the best ways to address chronic pain at the local level. The development of a pain management program is recommended to address the unmet needs of patients with chronic pain. Education in pain management is recommended for healthcare providers, including information regarding the benefits of non-pharmacologic therapies for pain management. The practice inquiry also supports the need for new policies at the local, tribal, and national levels to address pain as a growing public health issue.
89

Dynamic Regulation of Synaptic Transmission onto Serotonin Neurons by Antidepressants

Geddes, Sean D 23 November 2012 (has links)
Antidepressants are generally believed to exert their clinical efficacy by enhancing 5-HT transmission. Interestingly, sustained administration of selective serotonin (5-HT) reuptake inhibitors (SSRIs) strongly suppresses in the first few days the firing activity of 5-HT neurons in the dorsal raphe nucleus (DRN), thereby severely hampering the increase of 5-HT in target regions. Remarkably, the firing activity of 5-HT neurons gradually recovers over the time course of treatment and this recovery is believed to be accounted for by the desensitization of 5-HT1A somatodendritic autoreceptors. Here, we sought to investigate whether additional mechanisms might contribute to the dynamic regulation of excitability of 5-HT neurons during the course of SSRI treatments. Borrowing from the well-described homeostatic strengthening of glutamatergic synapses onto cortical pyramidal neurons following prolonged periods of inactivity, we hypothesized that a similar homeostatic-like regulation of synaptic strength might be operant on 5-HT cells during an SSRI treatment. To test this possibility, we used whole-cell electrophysiological recordings on acute midbrain slices to monitor glutamatergic synapses onto 5-HT neurons. We found that a two-day treatment with the SSRI citalopram induced a robust reduction in both the amplitude and frequency of AMPAR-mediated mEPSCs. We also show that this depression in synaptic strength, induced by an SSRI, is transient since excitatory drive onto 5-HT neurons was enhanced by 7 days of treatments. Altogether, these results document a dynamic regulation of glutamatergic synaptic transmission during the time course of a prolonged treatment with an SSRI. Further elucidation of the cellular and molecular mechanisms driving this synaptic plasticity might identify novel pharmacological target to shorten the delay of antidepressant action.
90

A framework for achieving whole life value of healthcare facilities through briefing and optioneering

Sengonzi, Ruth January 2011 (has links)
Since its inauguration in 1948, the National Health Service (NHS) has been providing “free at the point of delivery” healthcare to all UK citizens. However, lately, there has been unprecedented concern over the capability of most NHS hospitals to demonstrate best value in providing non-clinical service to NHS Trust customers. Demonstrating value is particularly important because of the current multi-billion pound expenditure towards modernising the healthcare service estate. Consequently, the present research aimed to respond to the need to demonstrate satisfactory Whole Life Value (WLV) delivery of healthcare facilities. This has been achieved by focusing on the improvement of front-end processes of construction briefing and optioneering, where most value can be embedded before progressing onto design and construction. The study reviewed extant literature in an attempt to construct a theoretical linkage between the three concepts of WLV, strategic briefing and optioneering. In addition, through a qualitative empirical study comprising interviews, workshops observations and a detailed case study, the same concepts were investigated within the context of NHS healthcare facilities. Key findings indicated that having a specific project strategy is vital to WLV delivery; and that selecting the right project and design options is dependent on first agreeing and clarifying a clinical service model/plan with clinicians. It was also found that improved construction briefing and optioneering involves adequately defining a customised whole life solution informed through purposeful communication and engagement with relevant stakeholders in contributing towards issues that directly affect how they use a healthcare facility. Another key finding was that WLV of healthcare facilities is defined through a whole life solution which is directly linked to its usefulness or utility value realisable by service users in achieving expected clinical outcomes over the facility's design life. Therefore, through briefing and optioneering, a healthcare facility's project strategy must be directly linked with specific needs and requirements (among other things) in order to reflect exactly what the stakeholders and end-users value in a healthcare built environment in the long term. These research findings were applied to inform the formulation of a better briefing and optioneering guidance framework applicable during project definition for satisfactory WLV delivery of healthcare schemes.

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