4,614 research outputs found
Introduction to morphological and functional evaluation of the heart and coronary arteries
In the last years, the number of clinical indications for the evaluation of the heart – with both computed tomography (CT) and magnetic resonance (MR) – exponentially grew. This evidence reflects the remarkable technological developments of both techniques allowing unprecedented spatial, temporal and contrast resolution levels and to comprehensively evaluate cardiac pathology, combining anatomical information with functional assessment and tissue characterization of myocardial diseases
Impact of heart rate on myocardial salvage in timely reperfused patients with STSegment elevation myocardial infarction. new insights from cardiovascular magnetic resonance
BACKGROUND: Previous studies evaluating the progression of the necrotic wave in relation to heart rate were carried out only in animal models of ST-elevated myocardial infarction (STEMI). Aim of the study was to investigate changes of myocardial salvage in relation to different heart rates at hospital admission in timely reperfused patients with STEMI by using cardiovascular magnetic resonance (CMR).
METHODS: One hundred-eighty-seven patients with STEMI successfully and timely treated with primary coronary angioplasty underwent CMR five days after hospital admission. According to the heart rate at presentation, patients were subcategorized into 5 quintiles: <55 bpm (group I, n = 44), 55-64 bpm (group II, n = 35), 65-74 bpm (group III, n = 35), 75-84 bpm (group IV, n = 37), ≥85 bpm (group V, n = 36). Area at risk, infarct size, microvascular obstruction (MVO) and myocardium salvaged index (MSI) were assessed by CMR using standard sequences.
RESULTS: Lower heart rates at presentation were associated with a bigger amount of myocardial salvage after reperfusion. MSI progressively decreased as the heart rates increased (0.54 group I, 0.46 group II, 0.38 group III, 0.34 group IV, 0.32 group V, p<0.001). Stepwise multivariable analysis showed heart rate, peak troponin and the presence of MVO were independent predictor of myocardial salvage. No changes related to heart rate were observed in relation to area at risk and infarct size.
CONCLUSIONS: High heart rates registered before performing coronary angioplasty in timely reperfused patients with STEMI are associated with a reduction in salvaged myocardium. In particular, salvaged myocardium significantly reduced when heart rate at presentation is ≥85 bpm
Enhancing ESL students academic writing skills through the term-paper
Tertiary ESL students find writing the academic term-paper a complex process as they grapple with issues about academic writing conventions and ethics. This paper examines tertiary students’ thoughts and perceptions in co-constructing knowledge about academic writing and how multi-drafting and feedback strategies enhance their academic literacy skills through term-paper writing. In particular, we examine the use of the term-paper as a pedagogical instrument incorporating the process approach to writing for developing academic writing skills among tertiary level students in Malaysia including the importance of multi-drafting, where students reflect on the writing of the multi-drafts and evaluate their learning while working in groups. The respondents are 38 Diploma in Business Management students from a Malaysian university enrolled in an academic writing course. Focus group interviews, group observations and respondents reflective journal entries provided the qualitative data. Our findings show that group multi-drafting and feedback processes enhanced students understanding of writing as a recursive process and sharpened their academic writing literacy knowledge in the areas of referencing, planning, idea generation, editing and revising. We conclude that the multi-draft term-paper approach as a pedagogical tool seems to be a feasible solution to heightening the academic writing skills and confidence of tertiary students
Genre analysis of the literature review section in hospitality and management research articles
Writing an effective literature review is not an easy task for novice writers of research articles, who are oftentimes unaware of the exact functions and purpose of this section; they are often unsuccessful in establishing the necessary connection between what has already been reviewed and the proposed research. This paper discusses the rhetorical patterns of the literature review (LR) section of Hospitality and Management (HM) research articles (RAs) from the perspective of genre analysis using the move structures as posited by Swales (2004). Twenty literature reviews from research articles in the Hospitality and Management discipline were analyzed to determine the move structure of the LR section. A moves analysis was carried out to identify the main moves and steps in the LR section. The analysis indicates that the LR sections display cyclical move patterns that show the presence of the 3 moves and their respective steps as postulated in Swales (2004) revised CARS model, but with some variations. The findings show that the LR section has Move 1 as an obligatory step and that HM RA writers favour making general statements about current situations as a beginning strategy. The findings further show that Move 2 Step 1B, ‘Adding to what is known’, is prevalent in the LR section because the writers will go on to contribute to the existing field of research by adding other research findings that are deemed necessary. Another outcome is that only Move 3-Step 1 is prevalent while the other 6 steps are either not found at all or are present in only a few of the samples
A roadmap to integrate astrocytes into Systems Neuroscience.
Systems neuroscience is still mainly a neuronal field, despite the plethora of evidence supporting the fact that astrocytes modulate local neural circuits, networks, and complex behaviors. In this article, we sought to identify which types of studies are necessary to establish whether astrocytes, beyond their well-documented homeostatic and metabolic functions, perform computations implementing mathematical algorithms that sub-serve coding and higher-brain functions. First, we reviewed Systems-like studies that include astrocytes in order to identify computational operations that these cells may perform, using Ca2+ transients as their encoding language. The analysis suggests that astrocytes may carry out canonical computations in a time scale of subseconds to seconds in sensory processing, neuromodulation, brain state, memory formation, fear, and complex homeostatic reflexes. Next, we propose a list of actions to gain insight into the outstanding question of which variables are encoded by such computations. The application of statistical analyses based on machine learning, such as dimensionality reduction and decoding in the context of complex behaviors, combined with connectomics of astrocyte-neuronal circuits, is, in our view, fundamental undertakings. We also discuss technical and analytical approaches to study neuronal and astrocytic populations simultaneously, and the inclusion of astrocytes in advanced modeling of neural circuits, as well as in theories currently under exploration such as predictive coding and energy-efficient coding. Clarifying the relationship between astrocytic Ca2+ and brain coding may represent a leap forward toward novel approaches in the study of astrocytes in health and disease
Design of a high-force-density tubular motor
This paper deals with the design, construction and experimental verification of a high force density, tubular, linear, permanent magnet motor, driven from a high power density matrix converter for an aerospace application. The work also describes the implementation and experimental verification of a novel, thermal management technique for the phase windings of electrical machines. The technique introduces a higher thermal conductivity path between the centre of the slot and the cooling arrangement, thus increasing the heat flow away from the slot centre. An introduction to the design of the motor is first given, after which an introduction to the technique is presented. A study of how the implementation of the technique affects motor performance is then presented. A detailed overview of the construction aspects is highlighted and finally, experimental validation is used to illustrate the comparison between the predicted results and the measured results, obtained from an instrumented, test rig
Glycine Cleavage System H Protein Is Essential for Embryonic Viability, Implying Additional Function Beyond the Glycine Cleavage System
Glycine cleavage system H protein (GCSH) is a component of the glycine cleavage system (GCS), a conserved protein complex that acts to decarboxylate glycine. Mutation of AMT or GLDC, encoding the GCS components aminomethyltransferase and glycine decarboxylase, can cause malformations of the developing CNS (neural tube defects (NTDs) and ventriculomegaly) as well as a post-natal life-limiting neurometabolic disorder, Non-Ketotic Hyperglycinemia. In contrast, it is unclear whether mutation of GCSH contributes to these conditions and we therefore investigated GCSH loss of function in mice. Mice that were heterozygous for a Gcsh null allele were viable and did not exhibit elevated plasma glycine. Moreover, heterozygous mutation of Gcsh did not increase the frequency of NTDs in Gldc mutant embryos. Homozygous Gcsh null mice were not recovered at post-natal stages. Analysis of litters at E8.5-10.5, revealed the presence of homozygous null embryos which were much smaller than littermates and had failed to develop beyond early post-implantation stages with no visible somites or head-folds. Hence, unlike null mutations of Gldc or Amt, which are compatible with embryonic survival despite the presence of NTDs, loss of Gcsh causes embryonic death prior to mid-gestation. Maternal supplementation with formate did not restore embryonic development beyond E7.5, suggesting that the primary cause of lethality was not loss of glycine cleavage activity or suppression of folate one-carbon metabolism. These findings suggest that GCSH has additional roles beyond function in the glycine cleavage system. We hypothesize that GCSH potentially acts in lipoylation of 2-oxoacid dehydrogenase proteins, as reported in bacteria
The surface ectoderm exhibits spatially heterogenous tension that correlates with YAP localisation during spinal neural tube closure in mouse embryos
The single cell layer of surface ectoderm (SE) which overlies the closing neural tube (NT) plays a crucial biomechanical role during mammalian NT closure (NTC), challenging previous assumptions that it is only passive to the force-generating neuroepithelium (NE). Failure of NTC leads to congenital malformations known as NT defects (NTDs), including spina bifida (SB) and anencephaly in the spine and brain respectively. In several mouse NTD models, SB is caused by misexpression of SE-specific genes and is associated with disrupted SE mechanics, including loss of rostrocaudal cell elongation believed to be important for successful closure. In this study, we asked how SE mechanics affect NT morphology, and whether the characteristic rostrocaudal cell elongation at the progressing closure site is a response to tension anisotropy in the SE. We show that blocking SE-specific E-cadherin in ex utero mouse embryo culture influences NT morphology, as well as the F-actin cable. Cell border ablation shows that cell shape is not due to tension anisotropy, but that there are regional differences in SE tension. We also find that YAP nuclear translocation reflects regional tension heterogeneity, and that its expression is sensitive to pharmacological reduction of tension. In conclusion, our results confirm that the SE is a biomechanically important tissue for spinal NT morphogenesis and suggest a possible role of spatial regulation of cellular tension which could regulate downstream gene expression via mechanically-sensitive YAP activity
Contexto, competencias y contenido de la Administración de los Servicios de Enfermería en los estudios de Grado de Enfermería
Se estudia el contexto, tanto profesional, personal del alumno y curricular de
la materia de Administración de los Servicios de Enfermería, perteneciente a la
titulación de Enfermería, en el ámbito del Espacio Europeo de Educación Superior
(EEES), así como las competencias específicas de la materia mediante la revisión
documental de diversos estudios relacionados con el tema.
Se describen los principales criterios para la implantación y desarrollo del
EEES, las competencias específicas y genéricas o transversales de Administración
de los Servicios de Enfermería así como los objetivos y contenidos generales
representados en mapa conceptual. Se proporciona además una extensa bibliografía
relacionada con el tema.
Para concluir, se destaca el papel aglutinante en la materia para el desarrollo
de habilidades que posibiliten las competencias, la importancia de la convergencia
de todas las titulaciones en el EEES y el cambio estructural, metodológico y
de actitud que conllevaIn this work the context, so much professional, is studied personal of the
student and curricular of the matter of Administration of the Services of
Infirmary, belonging to the ti de oflnfirmary, in the environment of the E uropean
Space of Superior Education (EEES), as well as the specific competitions of the
matter by means of the documental revision of diverse studies related with the
topic.
The main approaches are described for the installation and development of the
EEES, the specific and generic or traverse competitions of Administration of the
Services oflnfirmary as well as the objectives and general contents represented in
conceptual map. lt is also provided an extensive bibliography related with the
topic.
To conclude, he/she stands out the agglutinative paper in the matter for the
development of abilities that you/they facilitate the competitions, the importance
of the convergence of all careers university student in the EEES and the structural,
methodological change and of attitude that bear
Neogeography and seismic risk perception : a comparison between two case studies : Calabria, Southern Italy and Malta
Geography of perception aims at clarifying human behaviour by studying the concepts and images of the real world that a person elaborates on by considering the psychological and social aspects of man’s behaviour within an environment. In this context, a questionnaire was given to primary and middle school pupils in an area of Calabria (Southern Italy), which has recently been affected by an on-going seismic sequence widely felt by the local population. The same questionnaire was given to students in Malta (Central Mediterranean), an area considered to have a low-to-moderate seismic hazard, and where earthquake awareness is not culturally strong. In this way, the knowledge effectively possessed by the students (relating to age, experience and area of origin) are analysed; their analogous and differing perceptions on earthquakes in different areas are highlighted. The data collected can be used to project and create new informative tools through which students will become “geographic information volunteers” studying natural risks such as earthquakes, and augmenting the territory’s level of resilience.peer-reviewe
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