6,225 research outputs found

    EVALUATION OF BORON SUPPLEMENTATION IN SWINE AND POULTRY

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    The objectives of this dissertation were to evaluate dietary boron (B) supplementation as sodium borate in various swine models and broiler chicks through a series of experiments. The initial experiment evaluated supplemental B (0, 25, 50, and 100 ppm B) on serum insulin, glucose, and clinical chemistry panel of growing pigs. Serum insulin/glucose ratio tended to decrease linearly with increasing supplemental B in a fasting state (P = 0.08). These findings were more noticeable (linear effect, P = 0.02) in a postprandial state (~ 50 minutes following a meal). A series of follow-up studies further evaluating B supplementation (0, 5, and 25 ppm B) in sows, piglets, and grower and market pigs were conducted. In multiparous sows, B supplementation tended to result in sows farrowing fewer piglets (quadratic, P = 0.08) yet piglet birth weight was increased quadratically (P ≤ 0.05) with increasing B supplementation. Furthermore, B supplementation to multiparous sows resulted in a quadratic decrease in late gestation (d 80-90 of gestation) fasting serum insulin/glucose ratio (P = 0.02) whereas, in a postprandial state, serum insulin/glucose ratio was linearly increased (P = 0.02) with increasing B supplementation. In the second study, piglets from sows supplemented with dietary B exhibited an increase in the Mg content of the femur (quadratic effect, P = 0.02) at weaning. In the third study, both grower (70 kg BW) and market pigs supplemented with B had a greater kidney ash percentage (linear effect, P = 0.03; linear tendency, P = 0.08, respectively) compared to that of the control. Furthermore, grower pigs exhibited a linear increase in Mg concentration for the 3rd and 4th metacarpals (P = 0.05) with increasing B supplementation. In the final swine study, evaluating B supplementation on the apparent total tract digestibility (ATTD) and retention of nutrients in growing pigs resulted in a linear increase in both Mg absorption and digestibility regarding increasing B supplementation (P = 0.01 and P = 0.04, respectively). Lastly, an experiment evaluating B supplementation (0, 1, 2, 5, 10, 25, and 50 ppm B) to a semi-purified diet fed to broiler chicks resulted in a linear tendency for increasing tibia ash percentage (P = 0.08) with increasing supplemental B. Additionally, there was a greater tibia Mg concentration of birds supplemented B compared to control birds (P \u3c 0.01). In summation, B supplementation appeared to affect insulin concentration in both grower pigs and sows. Furthermore, B improved Mg absorption and digestibility in growing barrows while also affecting Mg concentrations in the bones of broilers, weaning pigs, and grower pigs, all suggesting B may play a key role in Mg metabolism

    Comparative Multiple Case Study into the Teaching of Problem-Solving Competence in Lebanese Middle Schools

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    This multiple case study investigates how problem-solving competence is integrated into teaching practices in private schools in Lebanon. Its purpose is to compare instructional approaches to problem-solving across three different programs: the American (Common Core State Standards and New Generation Science Standards), French (Socle Commun de Connaissances, de Compétences et de Culture), and Lebanese with a focus on middle school (grades 7, 8, and 9). The project was conducted in nine schools equally distributed among three categories based on the programs they offered: category 1 schools offered the Lebanese program, category 2 the French and Lebanese programs, and category 3 the American and Lebanese programs. Each school was treated as a separate case. Structured observation data were collected using observation logs that focused on lesson objectives and specific cognitive problem-solving processes. The two logs were created based on a document review of the requirements for the three programs. Structured observations were followed by semi-structured interviews that were conducted to explore teachers' beliefs and understandings of problem-solving competence. The comparative analysis of within-category structured observations revealed an instruction ranging from teacher-led practices, particularly in category 1 schools, to more student-centered approaches in categories 2 and 3. The cross-category analysis showed a reliance on cognitive processes primarily promoting exploration, understanding, and demonstrating understanding, with less emphasis on planning and executing, monitoring and reflecting, thus uncovering a weakness in addressing these processes. The findings of the post-observation semi-structured interviews disclosed a range of definitions of problem-solving competence prevalent amongst teachers with clear divergences across the three school categories. This research is unique in that it compares problem-solving teaching approaches across three different programs and explores underlying teachers' beliefs and understandings of problem-solving competence in the Lebanese context. It is hoped that this project will inform curriculum developers about future directions and much-anticipated reforms of the Lebanese program and practitioners about areas that need to be addressed to further improve the teaching of problem-solving competence

    KYT2022 Finnish Research Programme on Nuclear Waste Management 2019–2022 : Final Report

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    KYT2022 (Finnish Research Programme on Nuclear Waste Management 2019–2022), organised by the Ministry of Economic Affairs and Employment, was a national research programme with the objective to ensure that the authorities have sufficient levels of nuclear expertise and preparedness that are needed for safety of nuclear waste management. The starting point for public research programs on nuclear safety is that they create the conditions for maintaining the knowledge required for the continued safe and economic use of nuclear energy, developing new know-how and participating in international collaboration. The content of the KYT2022 research programme was composed of nationally important research topics, which are the safety, feasibility and acceptability of nuclear waste management. KYT2022 research programme also functioned as a discussion and information-sharing forum for the authorities, those responsible for nuclear waste management and the research organizations, which helped to make use of the limited research resources. The programme aimed to develop national research infrastructure, ensure the continuing availability of expertise, produce high-level scientific research and increase general knowledge of nuclear waste management

    Annual SHOT Report 2018

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    SHOT is affiliated to the Royal College of PathologistsAll NHS organisations must move away from a blame culture towards a just and learning culture. All clinical and laboratory staff should be encouraged to become familiar with human factors and ergonomics concepts. All transfusion decisions must be made after carefully assessing the risks and benefits of transfusion therapy. Collaboration and co-ordination among staff is vital

    Aerial Network Assistance Systems for Post-Disaster Scenarios : Topology Monitoring and Communication Support in Infrastructure-Independent Networks

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    Communication anytime and anywhere is necessary for our modern society to function. However, the critical network infrastructure quickly fails in the face of a disaster and leaves the affected population without means of communication. This lack can be overcome by smartphone-based emergency communication systems, based on infrastructure-independent networks like Delay-Tolerant Networks (DTNs). DTNs, however, suffer from short device-to-device link distances and, thus, require multi-hop routing or data ferries between disjunct parts of the network. In disaster scenarios, this fragmentation is particularly severe because of the highly clustered human mobility behavior. Nevertheless, aerial communication support systems can connect local network clusters by utilizing Unmanned Aerial Vehicles (UAVs) as data ferries. To facilitate situation-aware and adaptive communication support, knowledge of the network topology, the identification of missing communication links, and the constant reassessment of dynamic disasters are required. These requirements are usually neglected, despite existing approaches to aerial monitoring systems capable of detecting devices and networks. In this dissertation, we, therefore, facilitate the coexistence of aerial topology monitoring and communications support mechanisms in an autonomous Aerial Network Assistance System for infrastructure-independent networks as our first contribution. To enable system adaptations to unknown and dynamic disaster situations, our second contribution addresses the collection, processing, and utilization of topology information. For one thing, we introduce cooperative monitoring approaches to include the DTN in the monitoring process. Furthermore, we apply novel approaches for data aggregation and network cluster estimation to facilitate the continuous assessment of topology information and an appropriate system adaptation. Based on this, we introduce an adaptive topology-aware routing approach to reroute UAVs and increase the coverage of disconnected nodes outside clusters. We generalize our contributions by integrating them into a simulation framework, creating an evaluation platform for autonomous aerial systems as our third contribution. We further increase the expressiveness of our aerial system evaluation, by adding movement models for multicopter aircraft combined with power consumption models based on real-world measurements. Additionally, we improve the disaster simulation by generalizing civilian disaster mobility based on a real-world field test. With a prototypical system implementation, we extensively evaluate our contributions and show the significant benefits of cooperative monitoring and topology-aware routing, respectively. We highlight the importance of continuous and integrated topology monitoring for aerial communications support and demonstrate its necessity for an adaptive and long-term disaster deployment. In conclusion, the contributions of this dissertation enable the usage of autonomous Aerial Network Assistance Systems and their adaptability in dynamic disaster scenarios

    Anticholinergic use in the UK: longitudinal trends and associations with cognitive outcomes

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    Observational studies have shown an association between the use of anticholinergic drugs and various negative health outcomes. However, when studying cognitive outcomes, there is great heterogeneity in previous results. The objectives of the present thesis are threefold. First, to explore the longitudinal patterns of anticholinergic prescribing in the UK. Second, to examine the association between anticholinergic burden and dementia. Third, to probe the relationship between anticholinergic burden, general cognitive ability, and brain structural MRI in relatively healthy participants. Chapter 1 provides an overview of the role of acetylcholine as a neurotransmitter in the human body. It begins with a description of its molecular characteristics and continues with a summary of anatomical and cellular features of cholinergic pathways in the brain. The chapter concludes with a description of the relevance of cholinergic processing in cognition and Alzheimer’s disease. Chapter 2 gives a summary of anticholinergic drugs. It describes the history of anticholinergic compounds and their present use in medicine. It then appraises the tools used to gauge the anticholinergic potency of drugs. I conclude the Chapter by evaluating the available evidence on the effects of anticholinergic drugs on various important health outcomes. Chapter 3 focuses on UK Biobank, the sample used in all analyses presented in this thesis. The chapter briefly describes the conception of the study, the timeline of assessments, and the available variables. I focus in my descriptions on the variables that were used in the present thesis, especially cognitive tests, brain imaging, and linked health data. Chapters 4 to 6 present the empirical work conducted as part of this thesis. Chapter 4 presents an analysis of anticholinergic prescribing trends in UK primary care from the year 1990 to 2015. I first calculate an anticholinergic burden (AChB) according to 13 different anticholinergic scales and an average to derive a “Meta-scale”. I then describe the prevalence of anticholinergic prescribing and its longitudinal trend for all scales. I use different plots of age-, period- and cohort effects on the AChB according to the Meta-scale to evaluate the contributions of these effects to the linear longitudinal trend. The study finds AChB to have increased 9-fold over 25 years and that this effect was attributable to both age- and cohort/period-related changes. In other words, ageing of the sample is not sufficient to explain the increase in anticholinergic prescribing; cohort- or period-effects must have contributed to the observed changes. Chapter 5 explores the relationship between anticholinergic prescribing and dementia. Previous studies on this topic had provided varied results. One of the goals of the present study was to probe potential factors for this heterogeneity. We find that greater AChB according to most of the studied anticholinergic scales (standardised HRs range: 1.027-1.125), as well as the slope of anticholinergic change (HR=1.094; 95% CI: 1.068-1.119), are associated with dementia. However, we find that not all drug classes are associated with dementia. Antidepressants (HR=1.11, 95% CI=1.07-1.17), antiepileptics (HR=1.07, 95% CI=1.04-1.11), and the antidiuretic furosemide (HR=1.06, 95% CI=1.02-1.10) exhibit the strongest effects. Interestingly, when exploring the effects of groups of anticholinergic drugs with different anticholinergic potencies, only the moderate potency group shows significant associations with dementia (HR=1.10, 95% CI=1.05-1.15). Chapter 6 examines the association between AChB, general cognitive ability, and brain structural MRI. It aims both to explore the potential sources of heterogeneity in previous work, as well as to expand on it by studying relatively healthy community-dwelling adults. We study brain structural MRI in a much bigger sample (at least 5x bigger) and use many more outcomes than previous studies. We find weak, but significant associations between AChB and general cognitive ability, and with 7/9 individual cognitive tests (standardised betas (β) range: -0.039, -0.003). Again, AChB in only some drug classes is associated with lower general cognitive ability, especially β-lactam antibiotics (β=-0.035, pFDR. Finally, chapter 7 summarizes the findings presented in chapters 4 to 6. The chapter also provides a critique of the sample and of my approach when conducting the analyses presented in the present thesis. The chapter concludes by discussing suggestions for future work on this topic

    Learning disentangled speech representations

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    A variety of informational factors are contained within the speech signal and a single short recording of speech reveals much more than the spoken words. The best method to extract and represent informational factors from the speech signal ultimately depends on which informational factors are desired and how they will be used. In addition, sometimes methods will capture more than one informational factor at the same time such as speaker identity, spoken content, and speaker prosody. The goal of this dissertation is to explore different ways to deconstruct the speech signal into abstract representations that can be learned and later reused in various speech technology tasks. This task of deconstructing, also known as disentanglement, is a form of distributed representation learning. As a general approach to disentanglement, there are some guiding principles that elaborate what a learned representation should contain as well as how it should function. In particular, learned representations should contain all of the requisite information in a more compact manner, be interpretable, remove nuisance factors of irrelevant information, be useful in downstream tasks, and independent of the task at hand. The learned representations should also be able to answer counter-factual questions. In some cases, learned speech representations can be re-assembled in different ways according to the requirements of downstream applications. For example, in a voice conversion task, the speech content is retained while the speaker identity is changed. And in a content-privacy task, some targeted content may be concealed without affecting how surrounding words sound. While there is no single-best method to disentangle all types of factors, some end-to-end approaches demonstrate a promising degree of generalization to diverse speech tasks. This thesis explores a variety of use-cases for disentangled representations including phone recognition, speaker diarization, linguistic code-switching, voice conversion, and content-based privacy masking. Speech representations can also be utilised for automatically assessing the quality and authenticity of speech, such as automatic MOS ratings or detecting deep fakes. The meaning of the term "disentanglement" is not well defined in previous work, and it has acquired several meanings depending on the domain (e.g. image vs. speech). Sometimes the term "disentanglement" is used interchangeably with the term "factorization". This thesis proposes that disentanglement of speech is distinct, and offers a viewpoint of disentanglement that can be considered both theoretically and practically

    Estudo da remodelagem reversa miocárdica através da análise proteómica do miocárdio e do líquido pericárdico

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    Valve replacement remains as the standard therapeutic option for aortic stenosis patients, aiming at abolishing pressure overload and triggering myocardial reverse remodeling. However, despite the instant hemodynamic benefit, not all patients show complete regression of myocardial hypertrophy, being at higher risk for adverse outcomes, such as heart failure. The current comprehension of the biological mechanisms underlying an incomplete reverse remodeling is far from complete. Furthermore, definitive prognostic tools and ancillary therapies to improve the outcome of the patients undergoing valve replacement are missing. To help abridge these gaps, a combined myocardial (phospho)proteomics and pericardial fluid proteomics approach was followed, taking advantage of human biopsies and pericardial fluid collected during surgery and whose origin anticipated a wealth of molecular information contained therein. From over 1800 and 750 proteins identified, respectively, in the myocardium and in the pericardial fluid of aortic stenosis patients, a total of 90 dysregulated proteins were detected. Gene annotation and pathway enrichment analyses, together with discriminant analysis, are compatible with a scenario of increased pro-hypertrophic gene expression and protein synthesis, defective ubiquitinproteasome system activity, proclivity to cell death (potentially fed by complement activity and other extrinsic factors, such as death receptor activators), acute-phase response, immune system activation and fibrosis. Specific validation of some targets through immunoblot techniques and correlation with clinical data pointed to complement C3 β chain, Muscle Ring Finger protein 1 (MuRF1) and the dual-specificity Tyr-phosphorylation regulated kinase 1A (DYRK1A) as potential markers of an incomplete response. In addition, kinase prediction from phosphoproteome data suggests that the modulation of casein kinase 2, the family of IκB kinases, glycogen synthase kinase 3 and DYRK1A may help improve the outcome of patients undergoing valve replacement. Particularly, functional studies with DYRK1A+/- cardiomyocytes show that this kinase may be an important target to treat cardiac dysfunction, provided that mutant cells presented a different response to stretch and reduced ability to develop force (active tension). This study opens many avenues in post-aortic valve replacement reverse remodeling research. In the future, gain-of-function and/or loss-of-function studies with isolated cardiomyocytes or with animal models of aortic bandingdebanding will help disclose the efficacy of targeting the surrogate therapeutic targets. Besides, clinical studies in larger cohorts will bring definitive proof of complement C3, MuRF1 and DYRK1A prognostic value.A substituição da válvula aórtica continua a ser a opção terapêutica de referência para doentes com estenose aórtica e visa a eliminação da sobrecarga de pressão, desencadeando a remodelagem reversa miocárdica. Contudo, apesar do benefício hemodinâmico imediato, nem todos os pacientes apresentam regressão completa da hipertrofia do miocárdio, ficando com maior risco de eventos adversos, como a insuficiência cardíaca. Atualmente, os mecanismos biológicos subjacentes a uma remodelagem reversa incompleta ainda não são claros. Além disso, não dispomos de ferramentas de prognóstico definitivos nem de terapias auxiliares para melhorar a condição dos pacientes indicados para substituição da válvula. Para ajudar a resolver estas lacunas, uma abordagem combinada de (fosfo)proteómica e proteómica para a caracterização, respetivamente, do miocárdio e do líquido pericárdico foi seguida, tomando partido de biópsias e líquidos pericárdicos recolhidos em ambiente cirúrgico. Das mais de 1800 e 750 proteínas identificadas, respetivamente, no miocárdio e no líquido pericárdico dos pacientes com estenose aórtica, um total de 90 proteínas desreguladas foram detetadas. As análises de anotação de genes, de enriquecimento de vias celulares e discriminativa corroboram um cenário de aumento da expressão de genes pro-hipertróficos e de síntese proteica, um sistema ubiquitina-proteassoma ineficiente, uma tendência para morte celular (potencialmente acelerada pela atividade do complemento e por outros fatores extrínsecos que ativam death receptors), com ativação da resposta de fase aguda e do sistema imune, assim como da fibrose. A validação de alguns alvos específicos através de immunoblot e correlação com dados clínicos apontou para a cadeia β do complemento C3, a Muscle Ring Finger protein 1 (MuRF1) e a dual-specificity Tyr-phosphoylation regulated kinase 1A (DYRK1A) como potenciais marcadores de uma resposta incompleta. Por outro lado, a predição de cinases a partir do fosfoproteoma, sugere que a modulação da caseína cinase 2, a família de cinases do IκB, a glicogénio sintase cinase 3 e da DYRK1A pode ajudar a melhorar a condição dos pacientes indicados para intervenção. Em particular, a avaliação funcional de cardiomiócitos DYRK1A+/- mostraram que esta cinase pode ser um alvo importante para tratar a disfunção cardíaca, uma vez que os miócitos mutantes responderam de forma diferente ao estiramento e mostraram uma menor capacidade para desenvolver força (tensão ativa). Este estudo levanta várias hipóteses na investigação da remodelagem reversa. No futuro, estudos de ganho e/ou perda de função realizados em cardiomiócitos isolados ou em modelos animais de banding-debanding da aorta ajudarão a testar a eficácia de modular os potenciais alvos terapêuticos encontrados. Além disso, estudos clínicos em coortes de maior dimensão trarão conclusões definitivas quanto ao valor de prognóstico do complemento C3, MuRF1 e DYRK1A.Programa Doutoral em Biomedicin
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