931 resultados para Dorsal premammillary nucleus and cat exposure


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This work has as object the elaboration of social environmental indicator of disaster risk that are present in precarious areas of human occupation, related to intense environmental dynamic from the perspective of the studies about the subject in Geography. The District of Mãe Luiza in Natal, capital city of Rio Grande do Norte, was defined as the study area. The place was chosen because it presents –historically- several vulnerability conditions and exposure to disaster risk. After a local social environmental description, two indexes were elaborated: the Social Vulnerability Index (SVI or IVS in Portuguese), based on 17 (seventeen) variables arranged on a questionnaire addressed to the population nucleus of the district, on regular grid (systematic sampling), classified into 5 (five) levels of SV from the weighted average; and the Physical and Natural Exposure to the Mass Movements Index (EMMI or IEMM in Portuguese) which had 16 (sixteen) variables that feature conditions of exposure to the mass movements in the district with classified levels from the weighted average of 1 (one) to 5 (five). The relationship between these two results, specialized in the district map, produced the Social Environmental Vulnerability Index (SEVI or IVSA in Portuguese) of Mãe Luiza, also classified into 5 (five) levels, following the Boolean logic correlation for cartographic overlay with use of computer software ArcGIS v.9.3, being named as: Very Low; low; average; high; and Very High Environmental Vulnerability in District. The study is based on the methodology proposed by Guerra et al (2009) for EMMI and by Almeida (2010) for SVI. They were modified and adapted according to the local reality, producing a new methodology in this study area. It was concluded that the neighborhood has most of its area with High and Very High Socio-environmental vulnerability to disasters, defined seven (7) critical areas, with Very High IVSA, and hazards associated with mass movements or flooding. In the end, the main issues that were found, such as generating elements for proposing mitigation measures and/or the proposed interventions were enumerated, related to structural order of vulnerability factors: how low constructive pattern of households; poor urban drainage; Real Estate forsaken in landslide routes; infrastructure ready access roads and slope containment. And social: as a lack of education about environmental risk; income and education of residents; presence of persons with limited mobility and/or those with special needs. This reality highlights the need for urgent action applied to the resolution and/or reduction of these problems, which is focusing the end of this work.

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It is known that the catecholamine group is constituted by dopamine, noradrenaline and adrenaline, in which the synthesis is regulated by an enzyme named tyrosine hydroxylase. Thus, 3-hydroxytyramine/dopamine (DA) is a precursor of the noradrenaline and adrenaline synthesis and acts as a neurotransmitter in the central nervous system. The three main nuclei, named the retrorubral field (A8 group), the substantia nigra pars compacta (A9 group) and the ventral tegmental area (A10 group), are arranged in the die-mesencephalic portion and are involved in three complexes circuitries - the mesostriatal, mesolimbic and mesocortical pathways. These pathways are related to behavioral manifestations, motricity, learning, reward and pathologies such as Parkinson’s Disease and Schizophrenia. Thus, the aim of this study was to perform de morphological analysis of the A8, A9 and A10 nuclei of the common marmoset (Callithrix jacchus). The marmoset is a neotropical primate, whose morphological and functional characteristics supports the suitability of use of this animal in biomedical research. Coronal sections of the marmoset brain were submitted to cytoarchitectonic characterization and TH-immunohistochemistry. Based on the morphology of the neurons, it was possible to subdivide the A10 group in seven regions: interfascicular nucleus, raphe rostral linear nucleus and raphe caudal linear nucleus, in the middle line; paranigral and parainterfascicular nucleus, in the middle zone; rostral portion of the ventral tegmental area nucleus and parabrachial pigmented nucleus, located in the dorsolateral portion of the mesencephalic tegmentum. A9 group was divided into four regions: substantia nigra compacta dorsal and ventral tiers; substantia nigra compacta lateral and medial clusters. No subdivisions were founded into A8 group. These results revealed that A8, A9 and A10 are phylogenetically conserved between species, but it’s necessary to expand the studies about this compartmentalization, investigating its occurrence in other primate species or investigating its functional relevance.

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The accessory optical system, the pretectal complex, and superior colliculus are important control centers in a variety of eye movement, being extremely necessary for image formation, consequently to visual perception. The accessory optical system is constituted by the nuclei: dorsal terminal nucleus, lateral terminal nucleus, medial terminal nucleus and interstitial nucleus of the posterior superior fasciculus. From a functional point of view they contribute to the image stabilization, participating in the visuomotor activity where all system cells respond to slow eye movements and visual stimuli, which is important for the proper functioning of other visual systems. The pretectal complex comprises a group of nuclei situated in mesodiencephalic transition, they are: anterior pretectal nucleus, posterior pretectal nucleus, medial pretectal nucleus, olivary pretectal nucleus and the nucleus of the optic tract, all retinal projection recipients and functionally are related to the route of the pupillary light reflex and the optokinetic nystagmus. The superior colliculus is an important subcortical visual station formed by layers and has an important functional role in the control of eye movements and head in response to multisensory stimuli. Our aim was to make a mapping of retinal projections that focus on accessory optical system, the nuclei of pretectal complex and the superior colliculus, searching mainly for pretectal complex, better delineation of these structures through the anterograde tracing with the B subunit of cholera toxin (CTb) followed by immunohistochemistry and characterized (measured diameter) synaptic buttons present on the fibers / terminals of the nucleus complex pré-tectal. In our results accessory optical system, including a region which appears to be medial terminal nucleus and superior colliculus, were strongly marked by fibers / terminals immunoreactive CTb as well as pretectal complex in the nucleus: optic tract, olivary pretectal nucleus, anterior pretectal nucleus and posterior pretectal nucleus. According to the characterization of the buttons it was possible to make a better definition of these nucleus.

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BACKGROUND: Previous research has found accumulating evidence for atypical reward processing in autism spectrum disorders (ASD), particularly in the context of social rewards. Yet, this line of research has focused largely on positive social reinforcement, while little is known about the processing of negative reinforcement in individuals with ASD. METHODS: The present study examined neural responses to social negative reinforcement (a face displaying negative affect) and non-social negative reinforcement (monetary loss) in children with ASD relative to typically developing children, using functional magnetic resonance imaging (fMRI). RESULTS: We found that children with ASD demonstrated hypoactivation of the right caudate nucleus while anticipating non-social negative reinforcement and hypoactivation of a network of frontostriatal regions (including the nucleus accumbens, caudate nucleus, and putamen) while anticipating social negative reinforcement. In addition, activation of the right caudate nucleus during non-social negative reinforcement was associated with individual differences in social motivation. CONCLUSIONS: These results suggest that atypical responding to negative reinforcement in children with ASD may contribute to social motivational deficits in this population.

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Objectif. Les jeunes crossover sont définis comme des adolescents qui sont à la fois victimes de maltraitance et délinquants juvéniles. L'objectif de ce mémoire est d’examiner les relations entre les paramètres de la maltraitance (ex., récurrence, sous-types et variété) et les paramètres de la délinquance juvénile (ex., précocité, volume, variété, gravité moyenne et présence de sous-types) vécus par les jeunes crossover. Méthodes. La source des données est constituée de rapports officiels pour tous les adolescents et adolescentes québécois qui ont plaidé coupables ou ont été reconnus coupables d'un crime entre le 1e janvier 2005 et le 31 décembre 2010. D'abord, un portrait des jeunes crossover québécois est dressé à l’aide de statistiques descriptives. Ensuite, des analyses multivariées sont utilisées pour déterminer si les paramètres de la maltraitance prédisent les différentes dimensions de la délinquance et pour examiner les différences selon le sexe. Résultats. La délinquance des jeunes crossover est plus importante que celle des délinquants non-maltraités. Les expériences différentielles de la maltraitance sont liées à des paramètres hétérogènes de la délinquance juvénile. La récurrence de la maltraitance est un prédicteur important des paramètres de la délinquance ultérieure. De plus, la maltraitance est particulièrement influente sur la délinquance des garçons. Implications. Les interventions au sein des systèmes de la protection de la jeunesse et de la justice juvénile doivent être adaptées afin d'identifier les jeunes à risque de délinquance grave, de cibler les dimensions spécifiques de la maltraitance et d’entraver leurs liens à la délinquance ultérieure. L'intervention doit être privilégiée pour les victimes de multiples incidents de maltraitance et pour les garçons victimes de maltraitance.

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The growth rate of Acropora cervicornis branch tips maintained in the laboratory was measured before, during, and after exposure to elevated nitrate (5 and 10 µM NO3-), phosphate (2 and 4 µM P-PO43) and/or pCO2 (CO2 ~700 to 800 µatm). The effect of increased pCO2 was greater than that of nutrient enrichment alone. High concentrations of nitrate or phosphate resulted in significant decreases in growth rate, in both the presence and absence of increased pCO2. The effect of nitrate and phosphate enrichment combined was additive or antagonistic relative to nutrient concentration and pCO2 level. Growth rate recovery was greater after exposure to increased nutrients or CO2 compared to increased nutrients and CO2. If these results accurately predict coral response in the natural environment, it is reasonable to speculate that the survival and reef-building potential of this species will be significantly negatively impacted by continued coastal nutrification and projected pCO2 increases.

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Limited information on the East Antarctic Ice Sheet (EAIS) geometry during Marine Isotope Stage 3 (MIS 3; 60-25 ka) restricts our understanding of its behaviour during periods of climate and sea level change. Ice sheet models forced by global parameters suggest an expanded EAIS compared to the Holocene during MIS 3, but field evidence from East Antarctic coastal areas contradicts such modelling, and suggests that the ice sheet margins were no more advanced than at present. Here we present a new lake sediment record, and cosmogenic exposure results from bedrock, which confirm that Rauer Group (eastern Prydz Bay) was ice-free for much of MIS 3. We also refine the likely duration of the Last Glacial Maximum (LGM) glaciation in the region. Lacustrine and marine sediments from Rauer Group indicate the penultimate period of ice retreat predates 50 ka. The lacustrine record indicates a change from warmer/wetter conditions to cooler/drier conditions after ca. 35 ka. Substantive ice sheet re-advance, however, may not have occurred until much closer to 20 ka. Contemporary coastal areas were still connected to the sea during MIS 3, restricting the possible extent of grounded ice in Prydz Bay on the continental shelf. In contrast, relative sea levels (RSL) deduced from field evidence indicate an extra ice load averaging several hundred metres thicker ice across the Bay between 45 and 32 ka. Thus, ice must either have been thicker immediately inland (with a steeper ice profile), or there were additional ice domes on the shallow banks of the outer continental shelf. Further work is required to reconcile the differences between empirical evidence of past ice sheet histories, and the history predicted by ice sheet models from far-field temperature and sea level records.

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Background: Increased exposure to anticholinergic medication is problematic, particularly in those aged 80 years and older.

Objective: The aim of this systematic review was to identify tools used to quantify anticholinergic medication burden and determine the most appropriate tool for use in longitudinal research, conducted in those aged 80 years and older.

Methods: A systematic literature search was conducted across six electronic databases to identify existing tools. Data extraction was conducted independently by two researchers; studies describing the development of each tool were also retrieved and relevant data extracted. An assessment of quality was completed for all studies. Tools were assessed in terms of their measurement of the association between anticholinergic medication burden and a defined set of clinical outcomes, their development and their suitability for use in longitudinal research; the latter was evaluated on the basis of criteria defined as the key attributes of an ideal anticholinergic risk tool.

Results: In total, 807 papers were retrieved, 13 studies were eligible for inclusion and eight tools were identified. Included studies were classed as ‘very good’ or ‘good’ following the quality assessment analysis; one study was unclassified. Anticholinergic medication burden as measured in studies was associated with impaired cognitive and physical function, as well as an increased frequency of falls. The Drug Burden Index (DBI) exhibited most of the key attributes of an ideal anticholinergic risk tool.

Conclusion: This review identified the DBI as the most appropriate tool for use in longitudinal research focused on older people and their exposure to anticholinergic medication burden.

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OBJECTIVES: The aim of this study was to describe the epidemiology of Ebstein's anomaly in Europe and its association with maternal health and medication exposure during pregnancy.

DESIGN: We carried out a descriptive epidemiological analysis of population-based data.

SETTING: We included data from 15 European Surveillance of Congenital Anomalies Congenital Anomaly Registries in 12 European countries, with a population of 5.6 million births during 1982-2011. Participants Cases included live births, fetal deaths from 20 weeks gestation, and terminations of pregnancy for fetal anomaly. Main outcome measures We estimated total prevalence per 10,000 births. Odds ratios for exposure to maternal illnesses/medications in the first trimester of pregnancy were calculated by comparing Ebstein's anomaly cases with cardiac and non-cardiac malformed controls, excluding cases with genetic syndromes and adjusting for time period and country.

RESULTS: In total, 264 Ebstein's anomaly cases were recorded; 81% were live births, 2% of which were diagnosed after the 1st year of life; 54% of cases with Ebstein's anomaly or a co-existing congenital anomaly were prenatally diagnosed. Total prevalence rose over time from 0.29 (95% confidence interval (CI) 0.20-0.41) to 0.48 (95% CI 0.40-0.57) (p<0.01). In all, nine cases were exposed to maternal mental health conditions/medications (adjusted odds ratio (adjOR) 2.64, 95% CI 1.33-5.21) compared with cardiac controls. Cases were more likely to be exposed to maternal β-thalassemia (adjOR 10.5, 95% CI 3.13-35.3, n=3) and haemorrhage in early pregnancy (adjOR 1.77, 95% CI 0.93-3.38, n=11) compared with cardiac controls.

CONCLUSIONS: The increasing prevalence of Ebstein's anomaly may be related to better and earlier diagnosis. Our data suggest that Ebstein's anomaly is associated with maternal mental health problems generally rather than lithium or benzodiazepines specifically; therefore, changing or stopping medications may not be preventative. We found new associations requiring confirmation.

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Increasing research has highlighted the effects of changing climates on the occurrence and prevalence of toxigenic Aspergillus species producing aflatoxins. There is concern of the toxicological effects to human health and animal productivity following acute and chronic exposure that may affect the future ability to provide safe and sufficient food globally. Considerable research has focused on the detection of these toxins, based on the physicochemical and biochemical properties of the aflatoxin compounds, in agricultural products for human and animal consumption. As improvements in food security continue more regulations for acceptable levels of aflatoxins have arisen globally; the most stringent in Europe. These regulations are important for developing countries as aflatoxin occurrence is high significantly effecting international trade and the economy. In developed countries analytical approaches have become highly sophisticated, capable of attaining results with high precision and accuracy, suitable for regulatory laboratories. Regrettably, many countries that are affected by aflatoxin contamination do not have resources for high tech HPLC and MS instrumentation and require more affordable, yet robust equally accurate alternatives that may be used by producers, processors and traders in emerging economies. It is especially important that those companies wishing to exploit the opportunities offered by lucrative but highly regulated markets in the developed world, have access to analytical methods that will ensure that their exports meet their customers quality and safety requirements.

This work evaluates the ToxiMet system as an alternative approach to UPLC–MS/MS for the detection and determination of aflatoxins relative to current European regulatory standards. Four commodities: rice grain, maize cracked and flour, peanut paste and dried distillers grains were analysed for natural aflatoxin contamination. For B1 and total aflatoxins determination the qualitative correlation, above or below the regulatory limit, was good for all commodities with the exception of the dried distillers grain samples for B1 for which no calibration existed. For B1 the quantitative R2 correlations were 0.92, 0.92, 0.88 (<250 μg/kg) and 0.7 for rice, maize, peanuts and dried distillers grain samples respectively whereas for total aflatoxins the quantitative correlation was 0.92, 0.94, 0.88 and 0.91. The ToxiMet system could be used as an alternative for aflatoxin analysis for current legislation but some consideration should be given to aflatoxin M1 regulatory levels for these commodities considering the high levels detected in this study especially for maize and peanuts

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Aflatoxins are a group of carcinogenic compounds produced by Aspergillus fungi that can grow on different agricultural crops. Both acute and chronic exposure to these mycotoxins can cause serious illness. Due to the high occurrence of aflatoxins in crops worldwide fast and cost-effective analytical methods are required for the identification of contaminated agricultural commodities before they are processed into final products and placed on the market. In order to provide new tools for aflatoxin screening two prototype fast ELISA methods: one for the detection of aflatoxin B1 and the other for total aflatoxins were developed. Seven monoclonal antibodies with unique high sensitivity and at the same time good cross-reactivity profiles were produced. The monoclonal antibodies were characterized and two antibodies showing IC50 of 0.037 ng/mL and 0.031 ng/mL for aflatoxin B1 were applied in simple and fast direct competitive ELISA tests. The methods were validated for peanut matrix as this crop is one of the most affected by aflatoxin contamination. The detection capabilities of aflatoxin B1 and total aflatoxins ELISAs were 0.4 μg/kg and 0.3 μg/kg for aflatoxin B1, respectively, which are one of the lowest reported values. Total aflatoxins ELISA was also validated for the detection of aflatoxins B2, G1 and G2. The application of the developed tests was demonstrated by screening 32 peanut samples collected from the UK retailers. Total aflatoxins ELISA was further applied to analyse naturally contaminated maize porridge and distiller's dried grain with solubles samples and the results were correlated with these obtained by UHPLC-MS/MS method.

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This paper outlines the development of a crosscorrelation algorithm and a spiking neural network (SNN) for sound localisation based on real sound recorded in a noisy and dynamic environment by a mobile robot. The SNN architecture aims to simulate the sound localisation ability of the mammalian auditory pathways by exploiting the binaural cue of interaural time difference (ITD). The medial superior olive was the inspiration for the SNN architecture which required the integration of an encoding layer which produced biologically realistic spike trains, a model of the bushy cells found in the cochlear nucleus and a supervised learning algorithm. The experimental results demonstrate that biologically inspired sound localisation achieved using a SNN can compare favourably to the more classical technique of cross-correlation.

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Thesis (Ph.D.)--University of Washington, 2016-06

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Thesis (Ph.D.)--University of Washington, 2016-08

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The work presented in my thesis addresses the two cornerstones of modern astronomy: Observation and Instrumentation. Part I deals with the observation of two nearby active galaxies, the Seyfert 2 galaxy NGC 1433 and the Seyfert 1 galaxy NGC 1566, both at a distance of $\sim10$ Mpc, which are part of the Nuclei of Galaxies (NUGA) sample. It is well established that every galaxy harbors a super massive black hole (SMBH) at its center. Furthermore, there seems to be a fundamental correlation between the stellar bulge and SMBH masses. Simulations show that massive feedback, e.g., powerful outflows, in Quasi Stellar Objects (QSOs) has an impact on the mutual growth of bulge and SMBH. Nearby galaxies follow this relation but accrete mass at much lower rates. This gives rise to the following questions: Which mechanisms allow feeding of nearby Active Galactic Nuclei (AGN)? Is this feeding triggered by events, e.g., star formation, nuclear spirals, outflows, on $\sim500$ pc scales around the AGN? Does feedback on these scales play a role in quenching the feeding process? Does it have an effect on the star formation close to the nucleus? To answer these questions I have carried out observations with the Spectrograph for INtegral Field Observation in the Near Infrared (SINFONI) at the Very Large Telescope (VLT) situated on Cerro Paranal in Chile. I have reduced and analyzed the recorded data, which contain spatial and spectral information in the H-band ($1.45 \mic-1.85 \mic$) and K-band ($1.95 \mic-2.45 \mic$) on the central $10\arcsec\times10\arcsec$ of the observed galaxies. Additionally, Atacama Large Millimeter/Sub-millimeter Array (ALMA) data at $350$ GHz ($\sim0.87$ mm) as well as optical high resolution Hubble Space Telescope (HST) images are used for the analysis. For NGC 1433 I deduce from comparison of the distributions of gas, dust, and intensity of highly ionized emission lines that the galaxy center lies $\sim70$ pc north-northwest of the prior estimate. A velocity gradient is observed at the new center, which I interpret as a bipolar outflow, a circum nuclear disk, or a combination of both. At least one dust and gas arm leads from a $r\sim200$ pc ring towards the nucleus and might feed the SMBH. Two bright warm H$_2$ gas spots are detected that indicate hidden star formation or a spiral arm-arm interaction. From the stellar velocity dispersion (SVD) I estimate a SMBH mass of $\sim1.74\times10^7$ \msol. For NGC 1566 I observe a nuclear gas disk of $\sim150$ pc in radius with a spiral structure. I estimate the total mass of this disk to be $\sim5.4\times10^7$ \msol. What mechanisms excite the gas in the disk is not clear. Neither can the existence of outflows be proven nor is star formation detected over the whole disk. On one side of the spiral structure I detect a star forming region with an estimated star formation rate of $\sim2.6\times10^{-3}$ \msol\ yr$^{-1}$. From broad Br$\gamma$ emission and SVD I estimate a mean SMBH mass of $\sim5.3\times10^6$ \msol\ with an Eddington ratio of $\sim2\times10^{-3}$. Part II deals with the final tests of the Fringe and Flexure Tracker (FFTS) for LBT INterferometric Camera and the NIR/Visible Adaptive iNterferometer for Astronomy (LINC-NIRVANA) at the Large Binocular Telescope (LBT) in Arizona, USA, which I conducted. The FFTS is the subsystem that combines the two separate beams of the LBT and enables near-infrared interferometry with a significantly large field of view. The FFTS has a cryogenic system and an ambient temperature system which are separated by the baffle system. I redesigned this baffle to guarantee the functionality of the system after the final tests in the Cologne cryostat. The redesign did not affect any scientific performance of LINC-NIRVANA. I show in the final cooldown tests that the baffle fulfills the temperature requirement and stays $<110$ K whereas the moving stages in the ambient system stay $>273$ K, which was not given for the old baffle design. Additionally, I test the tilting flexure of the whole FFTS and show that accurate positioning of the detector and the tracking during observation can be guaranteed.