57 research outputs found

    Interconnection among River Flow Levels, Sediments Loads and Tides Conditions and Its Effect on the Coastal Wetlands Reduction

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    When the river supplies water to vulnerable environments, such as marshlands, it is vital to establish the expected impact mostly under a changing climate, and moreover, if a dam is being projected to solve energy demands. Soil characteristics, specifically sediment composition, are exposed to changes that modify this type of ecosystem and are rarely investigated. For this, a discharge period for an average historical year was analyzed to evaluate the magnitudes of the flows, with or without a dam. Also, it helped to identify the modification of the hydrodynamic regime between the sea and the lagoon system, particularly during the dry season but also checking the behavior in the rainy season. Results showed that the main problem with the construction of the dam on the San Pedro-Mezquital river would be the effect of a controlled flow that reaches the wetlands of the alluvial plains, affecting the sediment load in the estuarine and coastal ecology. However, after a readjustment period, the dam neither significantly changes the previous flood conditions of the coastal plain nor the sediment load will be a problem. However, if an additional sediment load is required to maintain the coastal microhabitats, there are different ways to provide it

    Quantitative electroencephalography reveals different physiological profiles between benign and remitting-relapsing multiple sclerosis patients

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    <p>Abstract</p> <p>Background</p> <p>A possible method of finding physiological markers of multiple sclerosis (MS) is the application of EEG quantification (QEEG) of brain activity when the subject is stressed by the demands of a cognitive task. In particular, modulations of the spectral content that take place in the EEG of patients with multiple sclerosis remitting-relapsing (RRMS) and benign multiple sclerosis (BMS) during a visuo-spatial task need to be observed.</p> <p>Methods</p> <p>The sample consisted of 19 patients with RRMS, 10 with BMS, and 21 control subjects. All patients were free of medication and had not relapsed within the last month. The power spectral density (PSD) of different EEG bands was calculated by Fast-Fourier-Transformation (FFT), those analysed being delta, theta, alpha, beta and gamma. Z-transformation was performed to observe individual profiles in each experimental group for spectral modulations. Lastly, correlation analyses was performed between QEEG values and other variables from participants in the study (age, EDSS, years of evolution and cognitive performance).</p> <p>Results</p> <p>Nearly half (42%) the RRMS patients showed a statistically significant increase of two or more standard deviations (SD) compared to the control mean value for the beta-2 and gamma bands (F = 2.074, p = 0.004). These alterations were localized to the anterior regions of the right hemisphere, and bilaterally to the posterior areas of the scalp. None of the BMS patients or control subjects had values outside the range of ± 2 SD. There were no significant correlations between these values and the other variables analysed (age, EDSS, years of evolution or behavioural performance).</p> <p>Conclusion</p> <p>During the attentional processing, changes in the high EEG spectrum (beta-2 and gamma) in MS patients exhibit physiological alterations that are not normally detected by spontaneous EEG analysis. The different spectral pattern between pathological and controls groups could represent specific changes for the RRMS patients, indicative of compensatory mechanisms or cortical excitatory states representative of some phases during the RRMS course that are not present in the BMS group.</p

    Cluster analysis of behavioural and event-related potentials during a contingent negative variation paradigm in remitting-relapsing and benign forms of multiple sclerosis

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    <p>Abstract</p> <p>Background</p> <p>Event-related potentials (ERPs) may be used as a highly sensitive way of detecting subtle degrees of cognitive dysfunction. On the other hand, impairment of cognitive skills is increasingly recognised as a hallmark of patients suffering from multiple sclerosis (MS). We sought to determine the psychophysiological pattern of information processing among MS patients with the relapsing-remitting form of the disease and low physical disability considered as two subtypes: 'typical relapsing-remitting' (RRMS) and 'benign MS' (BMS). Furthermore, we subjected our data to a cluster analysis to determine whether MS patients and healthy controls could be differentiated in terms of their psychophysiological profile.</p> <p>Methods</p> <p>We investigated MS patients with RRMS and BMS subtypes using event-related potentials (ERPs) acquired in the context of a Posner visual-spatial cueing paradigm. Specifically, our study aimed to assess ERP brain activity in response preparation (contingent negative variation -CNV) and stimuli processing in MS patients. Latency and amplitude of different ERP components (P1, eN1, N1, P2, N2, P3 and late negativity -LN) as well as behavioural responses (reaction time -RT; correct responses -CRs; and number of errors) were analyzed and then subjected to cluster analysis.</p> <p>Results</p> <p>Both MS groups showed delayed behavioural responses and enhanced latency for long-latency ERP components (P2, N2, P3) as well as relatively preserved ERP amplitude, but BMS patients obtained more important performance deficits (lower CRs and higher RTs) and abnormalities related to the latency (N1, P3) and amplitude of ERPs (eCNV, eN1, LN). However, RRMS patients also demonstrated abnormally high amplitudes related to the preparation performance period of CNV (cCNV) and post-processing phase (LN). Cluster analyses revealed that RRMS patients appear to make up a relatively homogeneous group with moderate deficits mainly related to ERP latencies, whereas BMS patients appear to make up a rather more heterogeneous group with more severe information processing and attentional deficits.</p> <p>Conclusions</p> <p>Our findings are suggestive of a slowing of information processing for MS patients that may be a consequence of demyelination and axonal degeneration, which also seems to occur in MS patients that show little or no progression in the physical severity of the disease over time.</p

    Subjective and objective measures

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    One of the greatest challenges in the study of emotions and emotional states is their measurement. The techniques used to measure emotions depend essentially on the authors’ definition of the concept of emotion. Currently, two types of measures are used: subjective and objective. While subjective measures focus on assessing the conscious recognition of one’s own emotions, objective measures allow researchers to quantify and assess the conscious and unconscious emotional processes. In this sense, when the objective is to evaluate the emotional experience from the subjective point of view of an individual in relation to a given event, then subjective measures such as self-report should be used. In addition to this, when the objective is to evaluate the emotional experience at the most unconscious level of processes such as the physiological response, objective measures should be used. There are no better or worse measures, only measures that allow access to the same phenomenon from different points of view. The chapter’s main objective is to make a survey of the main measures of evaluation of the emotions and emotional states more relevant in the current scientific panorama.info:eu-repo/semantics/acceptedVersio

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p&lt;0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p&lt;0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

    Attentional networks in neurodegenerative diseases: anatomical and functional evidence from the Attention Network Test

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    Introduction: Understanding alterations to brain anatomy and cognitive function associated with neurodegenerative diseases remains a challenge for neuroscience today. In experimental neuroscience, several computerised tests have been developed to contribute to our understanding of neural networks involved in cognition. The Attention Network Test (ANT) enables us to measure the activity of 3 attentional networks (alertness, orienting, and executive function). Objectives: The main aim of this review is to describe all the anatomical and functional alterations found in diverse neurological diseases using the ANT. Material and methods: We collected studies published since 2010 in the PubMed database that employed the ANT in different neurological diseases. Thirty-two articles were obtained, addressing multiple sclerosis, epilepsy, and Parkinson’s disease, among other disorders. Conclusions: Some of the anatomical structures proposed in the 3 attentional networks model were confirmed. The most relevant structures in the alertness network are the prefrontal cortex, parietal region, thalamus, and cerebellum. The thalamus is also relevant in the orienting network, together with posterior parietal regions. The executive network does not depend exclusively on the prefrontal cortex and anterior cingulate cortex, but also involves such subcortical structures as the basal ganglia and cerebellum and their projections towards the entire cortex. Resumen: Introducción: Comprender las alteraciones en la anatomía y función del cerebro en los procesos cognitivos para las enfermedades neurodegenerativas es aún un desafío para la neurociencia actual. Desde la neurociencia experimental, algunos tests computarizados han sido desarrollados para mejorar nuestro conocimiento de las redes neurales involucradas en la cognición. El Attention Network Test (ANT) permite medir la activad de las tres redes atencionales (alerta, orientación y función ejecutiva). Objetivos: El principal objetivo de esta revisión fue describir todas las alteraciones anatómicas y funcionales encontradas en diversas enfermedades neurológicas usando el ANT. Material y métodos: Un protocolo de revisión fue aplicado seleccionando estudios desde 2010 en la base de datos PubMed que involucraban al Attention Network Test en diferentes enfermedades neurológicas. Se obtuvieron treinta y dos artículos para esclerosis múltiple, epilepsia o Parkinson entre otras patologías. Conclusiones: Se confirman algunas de las estructuras anatómicas propuestas para el modelo de tres grandes redes atencionales. Las estructuras más relevantes para la red de alerta son la corteza prefrontal, regiones parietales, tálamo y el cerebelo. El tálamo es también relevante para la red de orientación, junto a regiones parietales posteriores. Respecto a la red ejecutiva, no depende exclusivamente de la corteza prefrontal y corteza cingulada anterior, sino también de estructuras subcorticales como los ganglios basales y el cerebelo y sus proyecciones hacia toda la corteza

    Isolation and molecular identifcation of laccase-producing saprophytic/ phytopathogenic mushroom-forming fungi from various ecosystems in Michoacan State, Mexico

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    The aim of this study was isolation and molecular identification of laccase-producing saprophytic/phytopathogen Basidiomycetes species from different geographic regions with dominant vegetation of Pinus, Abies, and Quercus spp. in the state of Michoacán, Mexico. Soil samples and visible mycelial aggregates were collected for fungal isolations. Soil samples were processed using a soil particle washing technique, where a selective Ascomycetes inhibitor and guaiacol, as an indicator of saprophytic Basidiomycetes growth, were used. Most of the isolates were obtained from samples collected in Parque Nacional, José Ma. Morelos (Km 23), Charo, Michoacán, Mexico. Based on sequence comparisons and phylogenetic analysis of internal transcribed spacer regions (ITS1-5.8S-ITS4) with respect to reference taxa, identification of saprophytic/phytopathogen Basidiomycetes species was carried out. In total, 15 isolates from 12 genera (i.e., Bjerkandera, Coriolopsis, Ganoderma, Hexagonia, Irpex, Limonomyces, Psathyrella, Peniophora, Phlebia, Phlebiopsis, Trametes, and Trichaptum) and one species from family Corticiaceae were identified. This study will be useful for further investigations on biodiversity of soil Basidiomycetes in different ecosystems. At present, these isolates are being used in our various lab experiments and can be useful in different industrial and bioremediation applications
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