10,277 research outputs found
Detailed quantification of cardiac ventricular myocardial architecture in the embryonic and fetal mouse heart by application of structure tensor analysis to high resolution episcopic microscopic data
The mammalian heart, which is one of the first organs to form and function during embryogenesis, develops from a simple tube into a complex organ able to efficiently pump blood towards the rest of the body. The progressive growth of the compact myocardium during embryonic development is accompanied by changes in its structural complexity and organisation. However, how myocardial myoarchitecture develops during embryogenesis remain poorly understood. To date, analysis of heart development has focused mainly on qualitative descriptions using selected 2D histological sections. High resolution episcopic microscopy (HREM) is a novel microscopic imaging technique that enables to obtain high-resolution three-dimensional images of the heart and perform detailed quantitative analyses of heart development. In this work, we performed a detailed characterization of the development of myocardial architecture in wildtype mice, from E14.5 to E18.5, by means of structure tensor analysis applied to HREM images of the heart. Our results shows that even at E14.5, myocytes are already aligned, showing a gradual change in their helical angle from positive angulation in the endocardium towards negative angulation in the epicardium. Moreover, there is gradual increase in the degree of myocardial organisation concomitant with myocardial growth. However, the development of the myoarchitecture is heterogeneous showing regional differences between ventricles, ventricular walls as well as between myocardial layers, with different growth patterning between the endocardium and epicardium. We also found that the percentage of circumferentially arranged myocytes within the LV significantly increases with gestational age. Finally, we found that fractional anisotropy (FA) within the LV gradually increases with gestational age, while the FA within RV remains unchanged
Cardiac multi-scale investigation of the right and left ventricle ex vivo: a review
The heart is a complex multi-scale system composed of components integrated at the subcellular, cellular, tissue and organ levels. The myocytes, the contractile elements of the heart, form a complex three-dimensional (3D) network which enables propagation of the electrical signal that triggers the contraction to efficiently pump blood towards the whole body. Cardiovascular diseases (CVDs), a major cause of mortality in developed countries, often lead to cardiovascular remodeling affecting cardiac structure and function at all scales, from myocytes and their surrounding collagen matrix to the 3D organization of the whole heart. As yet, there is no consensus as to how the myocytes are arranged and packed within their connective tissue matrix, nor how best to image them at multiple scales. Cardiovascular imaging is routinely used to investigate cardiac structure and function as well as for the evaluation of cardiac remodeling in CVDs. For a complete understanding of the relationship between structural remodeling and cardiac dysfunction in CVDs, multi-scale imaging approaches are necessary to achieve a detailed description of ventricular architecture along with cardiac function. In this context, ventricular architecture has been extensively studied using a wide variety of imaging techniques: ultrasound (US), optical coherence tomography (OCT), microscopy (confocal, episcopic, light sheet, polarized light), magnetic resonance imaging (MRI), micro-computed tomography (micro-CT) and, more recently, synchrotron X-ray phase contrast imaging (SR X-PCI). Each of these techniques have their own set of strengths and weaknesses, relating to sample size, preparation, resolution, 2D/3D capabilities, use of contrast agents and possibility of performing together with in vivo studies. Therefore, the combination of different imaging techniques to investigate the same sample, thus taking advantage of the strengths of each method, could help us to extract the maximum information about ventricular architecture and function. In this review, we provide an overview of available and emerging cardiovascular imaging techniques for assessing myocardial architecture ex vivo and discuss their utility in being able to quantify cardiac remodeling, in CVDs, from myocyte to whole organ
Phylogenetic inferences of Atelinae (Platyrrhini) based on multi-directional chromosome painting in Brachyteles arachnoides, Ateles paniscus paniscus and Ateles b. marginatus
We performed multi-directional chromosome painting in a comparative cytogenetic study of the three Atelinae species Brachyteles arachnoides, Ateles paniscus paniscus and Ateles belzebuth marginatus, in order to reconstruct phylogenetic relationships within this Platyrrhini subfamily. Comparative chromosome maps between these species were established by multi-color fluorescence in situ hybridization ( FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and four previously analyzed species from all four Atelinae genera were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 82 discrete chromosome characters. The results confirmed that Atelinae represent a monophyletic clade with a putative ancestral karyotype of 2n = 62 chromosomes. Phylogenetic analysis revealed an evolutionary branching sequence \{Alouatta \{Brachyteles \{Lagothrix and Ateles\}\}\} in Atelinae and \{Ateles belzebuth marginatus \{Ateles paniscus paniscus \{Ateles belzebuth hybridus and Ateles geoffroyi\}\}\} in genus Ateles. The chromosomal data support a re-evaluation of the taxonomic status of Ateles b. hybridus. Copyright (C) 2005 S. Karger AG, Basel
The high-Eddington NLS1 Ark 564 has the coolest corona
Ark 564 is an archetypal narrow-line Seyfert 1 that has been well observed in soft X-rays from 0.3â10 keV, revealing a steep spectrum, strong soft excess, iron K emission line and dramatic variability on the order of hours. Because of its very steep spectrum, observations of the source above 10 keV have been sparse. We report here on the first NuSTAR observation of Ark 564. The source was observed for 200 ks with NuSTAR, 50 ks of which were concurrent with Suzaku observations. NuSTAR and Suzaku observed a dramatic flare, in which the hard emission is clearly delayed with respect to the soft emission, consistent with previous detections of a low-frequency hard lag found in XMMâNewton data. The NuSTAR spectrum is well described by a low-temperature Comptonization continuum (with an electron temperature of 15 ± 2 keV), which irradiates a highly ionized disc. No further relativistic broadening or ionized absorption is required. These spectral results show that Ark 564 has one of the lowest temperature coronae observed by NuSTAR to date. We discuss possible reasons for low-temperature coronae in high-Eddington sources.European Research Council (340442
Behind the Intents: An In-depth Empirical Study on Software Refactoring in Modern Code Review
Code refactorings are of pivotal importance in modern code review. Developers may preserve, revisit, add or undo refactorings through changesâ revisions. Their goal is to certify that the driving intent of a code change is properly achieved. Developersâ intents behind refactorings may vary from pure structural improvement to facilitating feature additions and bug fixes. However, there is little understanding of the refactoring practices performed by developers during the code review process. It is also unclear whether the developersâ intents influence the selection, composition, and evolution of refactorings during the review of a code change. Through mining 1,780 reviewed code changes from 6 systems pertaining to two large open-source communities, we report the first in-depth empirical study on software refactoring during code review. We inspected and classified the developersâ intents behind each code change into 7 distinct categories. By analyzing data generated during the complete reviewing process, we observe: (i) how refactorings are selected, composed and evolved throughout each code change, and (ii) how developersâ intents are related to these decisions. For instance, our analysis shows developers regularly apply non-trivial sequences of refactorings that crosscut multiple code elements (i.e., widely scattered in the program) to support a single feature addition. Moreover, we observed that new developersâ intents commonly emerge during the code review process, influencing how developers select and compose their refactorings to achieve the new and adapted goals. Finally, we provide an enriched dataset that allows researchers to investigate the context and motivations behind refactoring operations during the code review process
What makes community-based physical activity programs for culturally and linguistically diverse older adults effects? : a systematic review
Objective: This integrative review aimed to determine the features of effective physical activity programs for culturally and linguistically diverse (CALD) older adults. Methods: We searched for relevant articles in MEDLINE, PubMed, Google Scholar, Scopus and CINAHL. Articles were selected for evaluation if they included CALD older adults and implemented physical activity programs with culturally specific design features. Consistent with the Whittemore and Knafl integrative review methodology, we used the Downs and Black Checklist, Mixed Methods Appraisal Tool and the McMaster University appraisal tool for quantitative studies to assess the quality of included articles. Results: Seven articles were included in this review. Effective community-based exercise or physical activity programs for CALD populations commonly featured close-to-home delivery, native language instruction and adaptations of culturally familiar activities. Conclusion: The provision of culturally appropriate community-based physical activity programs appears to support and encourage engagement among CALD older adults
May measurement month 2018: an analyses of blood pressure screening results from Cabo Verde.
Raised blood pressure (BP) is the biggest contributor to mortality and disease burden in Cabo Verde. May Measurement Month (MMM) is a global campaign set up in 2017 to raise awareness of high BP. In 2018, we aimed to expand the campaign by including a greater number of centres to increase awareness. Nine islands participated in MMM 2018. Volunteers (â„18âyears) were recruited through opportunistic sampling at a variety of screening sites. Each participant had three BP measurements and completed a questionnaire on demographic, lifestyle, and environmental factors. Hypertension was defined as a systolic BP â„140âmmHg and/or diastolic BP â„90âmmHg, or taking antihypertensive medication. In total, 98.0% of screenees provided three BP readings and multiple imputation using chained equations was used to impute missing readings. A total of 8008 individuals (mean age 40.4âyears; 68.5% female) were screened. After multiple imputation, 2666 (33.3%) individuals had hypertension, of whom 74.8% were aware of their previous diagnosis and 55.8% were taking antihypertensive medication. Of those on medication, 39.1% were controlled and of all hypertensives, 21.8% were controlled. We detected 44.2% of individuals with untreated hypertension and 60.9% of treated individuals were inadequately treated. The Cape Verdean population is ageing and consequently cardiovascular disease is increasing, with hypertension being an important risk factor. Corrective actions need to be taken by the government. MMM is an ideal initiative to reach the public by raising awareness of this major cardiovascular risk factor
Lesiones faciales en niños y adolescentes vĂctimas de agresiones
Child maltreatment may occur as the intentional use of power, effective or attempted, against children under 18 years old, that results or may result in actual or potential harm. It affects a vulnerable population, causing physical and/or emotional consequences persisting throughout their lives. This study aimed to characterize episodes of child maltreatment, with focus on facial injuries, in a Brazilian city (Teresina, PI). This is a retrospective study with a quantitative approach, carried out in the database at the Institute of Forensic MedicineinTeresina, between the years 2017 and 2019. All reports of bodily injury of children from 0 to 18 years were collected and statistically analyzed (SPSS 22.0). During the period analysis, 811 reports of bodily injury were identified. There was a predominance of female victims aged between 12 and 18 years old, the involvement of men with some family relationship with the victim was highly associated. Facial injuries represented 35.8% of the whole sample and 98.6% of those found in the head and neck region (41,6% of the total). The orbital (29.0%) was the most affected site, followed by the frontal (25.9%), malar (23.4%), labial (17.6%) and cheek area (11.4%). There is a high prevalence of injuries to the head and neck region, this factemphasizes the importance of a trained professional, especially a dental surgeon, in the analysis and interpretation of these injuries during forensic examination.info:eu-repo/semantics/publishedVersio
Volunteering for Research in Prison: Issues of Access, Rapport and Ethics and Emotions During Ethnography
Gaining access to formal institutions can be problematic for ethnographers. This is especially so when it comes to prisons where people are incarcerated by the state against their will for various crimes committed by them. Here, in such highly controlled environments, some authors have pointed out the lack of openness of correctional facilities to inquiry and the limited cooperation forthcoming from the various authorities that oversee them. Accordingly, this article examines the difficult processes undertaken to negotiate access to a high-security prison in Spain, and then maintain his role there for a 2-year period as a volunteer sports educator in order to explore the multiple meanings given to sport and physical activity in the prison setting by the prisoners, educational staff and the guards. The emotional costs and ethical dilemmas of sustaining working relationships with these different groups over time in order to achieve specific research goals are highlighted and reflections for future studies of prison life are offered
A novel PKC activating molecule promotes neuroblast differentiation and delivery of newborn neurons in brain injuries
Neural stem cells are activated within neurogenic niches in response to brain injuries. This results in the production of neuroblasts, which unsuccessfully attempt to migrate toward the damaged tissue. Injuries constitute a gliogenic/non-neurogenic niche generated by the presence of anti-neurogenic signals, which impair neuronal differentiation and migration. Kinases of the protein kinase C (PKC) family mediate the release of growth factors that participate in different steps of the neurogenic process, particularly, novel PKC isozymes facilitate the release of the neurogenic growth factor neuregulin. We have demonstrated herein that a plant derived diterpene, (EOF2; CAS number 2230806-06-9), with the capacity to activate PKC facilitates the release of neuregulin 1, and promotes neuroblasts differentiation and survival in cultures of subventricular zone (SVZ) isolated cells in a novel PKC dependent manner. Local infusion of this compound in mechanical cortical injuries induces neuroblast enrichment within the perilesional area, and noninvasive intranasal administration of EOF2 promotes migration of neuroblasts from the SVZ towards the injury, allowing their survival and differentiation into mature neurons, being some of them cholinergic and GABAergic. Our results elucidate the mechanism of EOF2 promoting neurogenesis in injuries and highlight the role of novel PKC isozymes as targets in brain injury regeneration
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