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1.
J Environ Manage ; 231: 653-665, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30390450

RESUMO

Semi-arid forests are water limited environments considered as low-productive. As a result, these forests usually end up unmanaged and abandoned, with the subsequent wild fire risk increasing, water yield decreasing and a general diminishing of the forest resilience. Hydrological-oriented silviculture could be a useful alternative that increases management possibilities by combining forest productivity and water yield. However, the slight water yield increase after forest management together with the low forest productivity, could make this option insufficient for semi-arid forests, and other goods and services should be included and quantified. In this sense, the present study analyzes to what extent semi-arid forest management for water yield results effective and profitable at catchment scale, and how does it improve when it is combined with other benefits such as biomass production and fire risk diminishing. To that end, the effects of forest management of semi-arid Aleppo pine post-fire regeneration stands are analyzed in terms of water yield (TETIS-VEG model), fire risk (KDBY index and FARSITE) and biomass production, at catchment scale. Regarding to water yield, the results confirmed the slight effect of forest management on its increase (average increase of 0.27 ±â€¯0.29 mm yr-1), at the same time that highlighted the role of the upper catchment area as an important water contributor. The management produced 4161.6 Mg of biomass, and decreased in 27±17% and 25.6 ±â€¯14.1% the fire risk and fire propagation, respectively. Finally, a simple economic estimation of the management profitability is carried out by means of comparing the Benefit/Cost ratio of the managed and unmanaged scenarios. Both scenarios were always above the unity when just considering water as benefit, although the unmanaged scenario produced a higher ratio, as no management costs are expended. Contrarily, when wildfire was also included into the evaluation, the situation is overturned for wildfires equal or higher than 1.5 day duration, where the forest management is shown as the most convenient alternative.


Assuntos
Incêndios , Água , Biomassa , Estudos de Viabilidade , Florestas
2.
J Med Syst ; 42(2): 38, 2018 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-29336001

RESUMO

The objective of this paper is to present a morphometric study of the middle cranial fossa from the study of 87 patients using cutting edge multislice computed tomography scans (32 detectors) and Magnetic Resonance Imaging. The study presents a detailed anatomical-radiological and morphometric analysis of the middle cranial fossa as well as its neurovascular elements in normal conditions. The implications of this investigation in training and clinical contexts are discussed.


Assuntos
Fossa Craniana Média/anatomia & histologia , Neuroimagem/métodos , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
3.
J Med Syst ; 40(6): 154, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27147517

RESUMO

We present a technological process based on the 3D Slicer software for the three-dimensional study of the brain's ventricular system with teaching purposes. It values the morphology of this complex brain structure, as a whole and in any spatial position, being able to compare it with pathological studies, where its anatomy visibly changes. 3D Slicer was also used to obtain volumetric measurements in order to provide a more comprehensive and detail representation of the ventricular system. We assess the potential this software has for processing high resolution images, taken from Magnetic Resonance and generate the three-dimensional reconstruction of ventricular system.


Assuntos
Ventrículos Cerebrais/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biologia Computacional , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Software , Interface Usuário-Computador
4.
J Med Syst ; 39(11): 151, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26370536

RESUMO

Parkinson's Disease is characterized by alterations in deep brain structures and pathways involved in movement control. However, the understanding of neuroanatomy and spatial relationships of deep brain structures remains a challenge for medical students. Recent developments in information technology may help provide new instructional material that addresses this problem. This paper aims to develop an interactive and digital tool to enhance the study of the anatomical and functional neurological basis involved in Parkinson's Disease. This tool allows the organization and exploration of complex neuroanatomical contents related with Parkinson's Disease in an attractive and interactive way. Educational implications of this tool are analyzed.


Assuntos
Encéfalo/anatomia & histologia , Simulação por Computador , Educação Médica/métodos , Modelos Biológicos , Doença de Parkinson/fisiopatologia , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Interface Usuário-Computador
5.
Anesth Analg ; 114(5): 1121-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22366843

RESUMO

BACKGROUND: For successful, fast-onset sciatic popliteal block (SPB), either a single injection above the division of the sciatic nerve, or 2 injections to block the tibial nerve (TN) and common peroneal nerve (CPN) separately have been recommended. In this study, we compared the traditional nerve stimulator (NS)-guided SPB above the division of the sciatic nerve with the ultrasound (US)-guided block with single injection of local anesthetic (LA) between the TN and CPN at the level of their division. We hypothesized that US-SPB with a single injection between TN and CPN would result in faster block onset than a single-injection NS-SPB. METHODS: Fifty-two patients were randomized to receive either an NS-SPB or a US-SPB. For both blocks, a single injection of 20 mL mepivacaine 1.5% was given using an automated injection pump while controlling for injection force. For NS-SPB, a TN response below 0.5 mA was sought 7 cm above the popliteal fossa crease (and proximal to the divergence of the TN and peroneal nerves). For US-SPB, the injection was made after a US-guided needle was inserted between the TN and CPN at the level of their separation. Motor response was not actively sought but registered if present. The location and spread of LA were evaluated by US in both groups. Onset of motor and sensory blocks was serially assessed in 5-minute intervals in the TN and CPN divisions and compared between the groups. RESULTS: All patients in both groups had successful block at 30 minutes after the injection, defined as sensory block to allow surgery without supplementation. A higher proportion of patients in the US-SPB group had a complete sensory (80% vs 4%, P < 0.001) and motor block (60% vs 8%, P < 0.001), defined as anesthesia and paralysis in all nerve territories, at 15 minutes after injection. US signs of intraepineural injection were present in 19 patients (73%) in the NS-SPB group and 25 patients (100%) in the US-SPB group (P < 0.001). CONCLUSIONS: A single injection of LA in US-SPB with needle insertion at the separation of the TN and CPN results in a similar success rate at 30 minutes; however, more patients in the US-SPB group than in the NS-SPB group had complete block at 15 minutes.


Assuntos
Bloqueio Nervoso/métodos , Nervo Isquiático/diagnóstico por imagem , Idoso , Anestésicos Locais/administração & dosagem , Método Duplo-Cego , Estimulação Elétrica , Feminino , Hallux Valgus/cirurgia , Humanos , Estimativa de Kaplan-Meier , Masculino , Mepivacaína/administração & dosagem , Pessoa de Meia-Idade , Neurônios Motores/efeitos dos fármacos , Bloqueio Nervoso/efeitos adversos , Medição da Dor/métodos , Parestesia/etiologia , Células Receptoras Sensoriais/efeitos dos fármacos , Resultado do Tratamento , Ultrassonografia
6.
Sci Total Environ ; 825: 153805, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35157867

RESUMO

The sustainability of agriculture in the Mediterranean climate is challenged by high irrigation water demands and nitrogen fertilizer losses to the environment, causing significant pressure on groundwater resources and groundwater-dependent ecosystems. Advanced irrigation technologies and improved fertilizer management have been promoted as key solutions to reduce the agricultural impact on aquatic systems. However, it remains unclear how different irrigation-fertilizer practices perform on the long-term under a highly variable climate, such as the Mediterranean one. Here, we conduct hydrological simulations over a fifty-year period to quantify the magnitude and dynamics of groundwater recharge and nitrogen leaching under five real-case irrigation-fertilizer practices observed in Valencia (eastern Spain). The Valencian Region is the largest citrus-producing region of Europe and current irrigation-fertilizer practices reflect the ongoing transformation of irrigation systems from flood to drip irrigation. Our simulations highlight three major implications of the irrigation transformation for groundwater resources. First, the transformation from flood to drip irrigation reduces the recharge fraction (19% vs. 16%) and especially the nitrogen leaching fraction (33% vs. 18%) on the long term. Second, the long-term performance of the two irrigation practices is subject to substantial inter-annual differences controlled by precipitation variability. The sensitivity of recharge and nitrogen leaching to annual meteorological conditions is stronger in drip irrigation, which eventually leads to a similar performance of flood and drip irrigation in wet years if fertilizer inputs are similar. Third, we identify a pronounced year-to-year nitrogen memory in the soil, whereby an enhanced (decreased) nitrogen leaching is observed after anomalously dry (wet) years, affecting the performance of irrigation-fertilizer practices. Overall, the study demonstrates the highly variable nature of the performance of irrigation-fertilizer practices, and the major findings can guide future efforts in designing sustainable water management strategies for agricultural areas with a Mediterranean climate.


Assuntos
Água Subterrânea , Nitrogênio , Irrigação Agrícola , Agricultura , Ecossistema , Fertilizantes/análise , Inundações , Nitrogênio/análise , Solo , Água
7.
Drug News Perspect ; 22(8): 481-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20016857

RESUMO

Ischemic stroke is associated with a high rate of disability and death. Establishing valid biomarkers could help accelerate the approval of promising new therapies for stroke. Whereas many serum biomarkers have been evaluated, possible imaging biomarkers of stroke lack validation. Magnetic resonance imaging (MRI) is a very sensitive technique to study acute stroke and MRI parameters have been established to assess the outcome of acute stroke. This review reassesses the criteria for the validation of MRI biomarkers of acute ischemic stroke (MRI-BAS). Seven criteria were used to review the validity of the main MRI-BAS: vascular status, lesion volume, reversibility on diffusion-weighted imaging, perfusion alteration, penumbra studied with diffusion-perfusion mismatch, clinical-diffusion mismatch, diffusion-angiography mismatch and hemorrhagic transformation. We analyzed the definitions of these biomarkers and the extent to which each fulfills the criteria for validation and found that few MRI-BAS have been fully validated. Further studies should help to improve the validation of current MRI-BAS and develop new biomarkers.


Assuntos
Isquemia Encefálica/diagnóstico , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico , Biomarcadores/metabolismo , Isquemia Encefálica/fisiopatologia , Humanos , Acidente Vascular Cerebral/fisiopatologia , Estudos de Validação como Assunto
8.
Sci Total Environ ; 639: 725-741, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29803044

RESUMO

Hydrology-oriented forest management sets water as key factor of the forest management for adaptation due to water is the most limiting factor in the Mediterranean forest ecosystems. The aim of this study was to apply Bayesian Network modeling to assess potential indirect effects and trade-offs when hydrology-oriented forest management is applied to a real Mediterranean forest ecosystem. Water, carbon and nitrogen cycles, and forest fire risk were included in the modeling framework. Field data from experimental plots were employed to calibrate and validate the mechanistic Biome-BGCMuSo model that simulates the storage and flux of water, carbon, and nitrogen between the ecosystem and the atmosphere. Many other 50-year long scenarios with different conditions to the ones measured in the field experiment were simulated and the outcomes employed to build the Bayesian Network in a linked chain of models. Hydrology-oriented forest management was very positive insofar as more water was made available to the stand because of an interception reduction. This resource was made available to the stand, which increased the evapotranspiration and its components, the soil water content and a slightly increase of deep percolation. Conversely, Stemflow was drastically reduced. No effect was observed on Runof due to the thinning treatment. The soil organic carbon content was also increased which in turn caused a greater respiration. The long-term effect of the thinning treatment on the LAI was very positive. This was undoubtedly due to the increased vigor generated by the greater availability of water and nutrients for the stand and the reduction of competence between trees. This greater activity resulted in an increase in GPP and vegetation carbon, and therefore, we would expect a higher carbon sequestration. It is worth emphasizing that this extra amount of water and nutrients was taken up by the stand and did not entail any loss of nutrients.

9.
Psychopharmacology (Berl) ; 191(3): 805-11, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17019564

RESUMO

INTRODUCTION: Drug induced parkinsonism (DIP) is directly related to dopamine D2 receptor blockade. However, there are many references describing parkinsonian signs (PS) in naive-patients. In our previous study, we observed lower DAT binding in a group of first-episode schizophrenic patients after short-term treatment with risperidone, compared with age-matched healthy controls. AIM: To clarify if DAT decrease could be an illness trait, excluding the effect of antipsychotics on DAT availability, and to determine whether DAT availability before treatment with antipsychotics may predict subsequent development of PS. MATERIALS AND METHODS: A new series of 20 neuroleptic-naive schizophrenic patients and 15 healthy subjects was recruited. SPECT with [(123)I] FP-CIT (DaTSCAN(R)) was performed before starting antipsychotics and after 4 weeks of treatment. PS and psychopathological status were assessed by the Simpson-Angus (SAS), CGI and PANSS scales. Quantitative analyses of SPECTs were performed using ROIs placed in the caudate, putamen and occipital cortex. RESULTS: Schizophrenic patients showed lower DAT binding compared with the healthy subjects at baseline (p<0.001) and after a 4-week-treatment period (p=0.001). Six out of eight schizophrenic patients of the DIP group were symptomatic for PS at baseline, in comparison to two out of 12 in the NoDIP group. Nonetheless, no differences were observed on DAT between DIP and NoDIP, neither at baseline (p=0.360) nor at endpoint (p=0.984). Finally, no differences between baseline-endpoint DAT binding were observed, neither in the DIP group (p=0.767) nor in the NoDIP group (p=0.093). CONCLUSION: Our new series of first-episode naive-schizophrenic patients (1) points out DAT dysfunction as an illness trait due to the significantly lower DAT binding in schizophrenic patients in comparison to healthy subjects; (2) supports the results of other authors who describe PS in never-treated patients; (3) confirms that [(123)I] FP-CIT does not allow us to predict which patients will develop parkinsonism due to the lack of differences between DIP and NoDIP patients; and (4) confirms a null effect of antipsychotics on DAT due to the lack of differences in [(123)I] FP-CIT before and after a 4-week-treatment period.


Assuntos
Antipsicóticos/uso terapêutico , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neostriado/metabolismo , Doença de Parkinson Secundária/etiologia , Risperidona/uso terapêutico , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico , Adulto , Antipsicóticos/efeitos adversos , Núcleo Caudado/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/efeitos dos fármacos , Regulação para Baixo , Feminino , Humanos , Masculino , Neostriado/diagnóstico por imagem , Neostriado/efeitos dos fármacos , Doença de Parkinson Secundária/metabolismo , Escalas de Graduação Psiquiátrica , Putamen/metabolismo , Risperidona/efeitos adversos , Esquizofrenia/complicações , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/metabolismo , Índice de Gravidade de Doença , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tropanos/metabolismo
10.
Psychopharmacology (Berl) ; 181(2): 401-6, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15830229

RESUMO

RATIONALE: Drug-induced parkinsonism (DIP) is one of the main causes of treatment drop-out in schizophrenic patients causing a high incidence of relapse that leads patients to a bad clinical prognosis. The dopaminergic nigrostriatal pathway is involved in the movement control, so the study of the dopamine transporter (DAT) could be of great value to determine its implication in the appearance of DIP. OBJECTIVE: The goal of the study is to determine the striatal DAT binding assessed with [(123)I] FP-CIT SPECT in first-episode neuroleptic-naive schizophrenic in-patients with DIP after short-term antipsychotic treatment. METHOD: The [(123)I] FP-CIT binding ratios of ten schizophrenic in-patients who developed DIP during the first 4-week period of risperidone treatment (6+/-2 mg/day) were compared with ten schizophrenic in-patients treated with the same doses of risperidone and who do not developed DIP and with ten age-matched healthy subjects. Quantitative analyses of SPECTs were performed using regions of interest located in caudate, putamen and occipital cortex. Parkinsonism was assessed by the Simpson-Angus Scale and the psychopathological status by the Clinical General Impression and Positive and Negative Syndrome Scales. RESULTS: Whole striatal [(123)I] FP-CIT binding ratios were significantly lower in patients with and without DIP than in healthy subjects (p<0.001). This was also observed in whole putamen (p<0.001) and caudate nucleus (p<0.001). Females showed higher whole striatal [(123)I] FP-CIT binding ratios than males (p<0.05). No differences in psychopathological scales were observed between patients with and without DIP. CONCLUSION: Our first-episode schizophrenic patients with and without DIP after short-term risperidone treatment have a decreased striatal DAT binding assessed with [(123)I] FP-CIT. This alteration could be related to the schizophrenic disease or may be secondary to the antipsychotic treatment.


Assuntos
Neostriado/metabolismo , Doença de Parkinson Secundária/induzido quimicamente , Esquizofrenia/metabolismo , Tropanos/metabolismo , Adulto , Antipsicóticos/efeitos adversos , Antipsicóticos/uso terapêutico , Ligação Competitiva , Humanos , Radioisótopos do Iodo , Neostriado/diagnóstico por imagem , Neostriado/efeitos dos fármacos , Esquizofrenia/tratamento farmacológico , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tropanos/farmacocinética
11.
Sci Total Environ ; 499: 510-9, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25053250

RESUMO

Economic instruments can be used to control groundwater nitrate pollution due to the intensive use of fertilizers in agriculture. In order to test their efficiency on the reduction of nitrate leaching, we propose an approach based on the combined use of production and pollution functions to derive the impacts on the expected farmer response of these instruments. Some of the most important factors influencing nitrate leaching and crop yield are the type of soil and the climatic conditions. Crop yield and nitrate leaching responses to different soil and climatic conditions were classified by means of a cluster analysis, and crops located in different areas but with similar response were grouped for the analysis. We use a spatial economic optimization model to evaluate the potential of taxes on nitrogen fertilizers, water prices, and taxes on nitrate emissions to reduce nitrate pollution, as well as their economic impact in terms of social welfare and farmers' net benefits. The method was applied to the Mancha Oriental System (MOS) in Spain, a large area with different soil types and climatic conditions. We divided the study area into zones of homogeneous crop production and nitrate leaching properties. Results show spatially different responses of crop growth and nitrate leaching, proving how the cost-effectiveness of pollution control instruments is contingent upon the spatial heterogeneities of the problem.


Assuntos
Agricultura/métodos , Clima , Poluentes do Solo/análise , Poluição da Água/prevenção & controle , Agricultura/economia , Produtos Agrícolas/crescimento & desenvolvimento , Nitratos/análise , Solo/química , Espanha , Poluição da Água/economia
12.
Sci Total Environ ; 499: 463-80, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25042417

RESUMO

The agricultural sector faces the challenge of ensuring food security without an excessive burden on the environment. Simulation models provide excellent instruments for researchers to gain more insight into relevant processes and best agricultural practices and provide tools for planners for decision making support. The extent to which models are capable of reliable extrapolation and prediction is important for exploring new farming systems or assessing the impacts of future land and climate changes. A performance assessment was conducted by testing six detailed state-of-the-art models for simulation of nitrate leaching (ARMOSA, COUPMODEL, DAISY, EPIC, SIMWASER/STOTRASIM, SWAP/ANIMO) for lysimeter data of the Wagna experimental field station in Eastern Austria, where the soil is highly vulnerable to nitrate leaching. Three consecutive phases were distinguished to gain insight in the predictive power of the models: 1) a blind test for 2005-2008 in which only soil hydraulic characteristics, meteorological data and information about the agricultural management were accessible; 2) a calibration for the same period in which essential information on field observations was additionally available to the modellers; and 3) a validation for 2009-2011 with the corresponding type of data available as for the blind test. A set of statistical metrics (mean absolute error, root mean squared error, index of agreement, model efficiency, root relative squared error, Pearson's linear correlation coefficient) was applied for testing the results and comparing the models. None of the models performed good for all of the statistical metrics. Models designed for nitrate leaching in high-input farming systems had difficulties in accurately predicting leaching in low-input farming systems that are strongly influenced by the retention of nitrogen in catch crops and nitrogen fixation by legumes. An accurate calibration does not guarantee a good predictive power of the model. Nevertheless all models were able to identify years and crops with high- and low-leaching rates.


Assuntos
Agricultura , Monitoramento Ambiental/métodos , Fertilizantes/análise , Modelos Químicos , Nitratos/análise , Poluentes do Solo/análise , Solo/química , Áustria , Monitoramento Ambiental/instrumentação , Fertilizantes/estatística & dados numéricos , Água Subterrânea/química , Nitrogênio/análise
13.
J Neurotrauma ; 26(10): 1823-34, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19754248

RESUMO

Brain damage caused by an acute injury depends on the initial severity of the injury and the time elapsed after the injury. To determine whether these two variables activate common mechanisms, we compared the response of the rat medial septum to insult with a graded series of concentrations of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) with the time-course effects of a low dose of AMPA. For this purpose we conducted a dose-response study at concentrations of AMPA between 0.27 and 10.8 nmol to measure atrophy of the septal area, losses of cholinergic and GABAergic neurons, astroglial and microglial reactions, and calcification. Cholinergic neurons, whose loss paralleled the degree of septal atrophy produced by AMPA, are more sensitive than GABAergic neurons to the injury produced by AMPA. At doses of AMPA above 2.7 nmol, calcification and the degree of microglial reaction increased only in the GABAergic region of the septal area, whereas atrophy and neuronal loss reached a plateau. We chose the 2.7-nmol dose of AMPA to determine how these parameters were modified between 4 days and 6 months after injection. We found that atrophy and neuronal loss increased progressively through the 6-month study period, whereas astrogliosis ceased to be observed after 1 month, and calcium precipitates were never detected. We conclude that septal damage does not increase with the intensity of an excitotoxic insult. Rather, it progresses continuously after the insult. Because these two situations involve different mechanisms, short-term paradigms are inappropriate for interpreting the pathogenic mechanisms responsible for long-term neurodegenerative processes.


Assuntos
Dano Encefálico Crônico/fisiopatologia , Lesões Encefálicas/fisiopatologia , Degeneração Neural/fisiopatologia , Neurotoxinas/toxicidade , Núcleos Septais/fisiopatologia , Acetilcolina/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Atrofia/induzido quimicamente , Atrofia/patologia , Atrofia/fisiopatologia , Dano Encefálico Crônico/induzido quimicamente , Dano Encefálico Crônico/patologia , Lesões Encefálicas/patologia , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta a Droga , Agonistas de Aminoácidos Excitatórios/toxicidade , Gliose/induzido quimicamente , Gliose/patologia , Gliose/fisiopatologia , Masculino , Microglia/efeitos dos fármacos , Microglia/patologia , Degeneração Neural/induzido quimicamente , Degeneração Neural/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Núcleos Septais/patologia , Tempo , Fatores de Tempo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/toxicidade , Ácido gama-Aminobutírico/metabolismo
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