271 research outputs found
Monitoramento Agrícola a Partir de Imagens Aéreas e WebMapping .
bitstream/CNPDIA/10446/1/BPD08_2004.pd
A familial partial AZFb-c microdeletion associated with diferente fértile phenotypes
After the Klinefelter syndrome, Y chromosome microdeletions are the second most frequent genetic cause of spermatogenic failure resulting in male infertility. Y chromosome microdeletions, encompassing one or more of the three AZF regions, are associated with diverse testicular histology, ranging from Sertoli-cell-only syndrome (AZFa del), maturation arrest (AZFb del) to hypospermatogenesis (AZFc del). The molecular screening of these regions is routinely performed in the work-up of infertile patients with azoospermia or severe oligozoospermia as each one has different prognostic values, both in terms of clinical decision-making and appropriate genetic counselling as well as for understanding the etiology of spermatogenesis impairment. Different partial AZFc deletions were already described, although it is still controversial if these are truly a genetic risk factor for spermatogenesis impairment or a deletional variant without phenotypic consequences.
Here we present the molecular results obtained after AZF analysis of two infertile brothers (both diagnosed with oligoteratoastenozoospermia), and of their fertile father. Several multiplex-PCR assays were performed with distinct sets of STS markers, specific for the three AZF regions.
The molecular analysis revealed that all three men presented the same partial AZFb/c microdeletion, namely the absence of the sY1197, sY1291 and sY1192 STSs. This microdeletion probably results from the recombination of amplicons b1/b3, reducing the gene copy number of PRY, BPY, DAZ, and RBMY.
The b1/b3 deletion is rare and its influence on spermatogenesis is still not clear since it can be found in men with severe oligozoospermia or with normal sperm counts. Our result suggests that b1/b3 del is most likely a risk factor predisposing to spermatogenic failure, but is not sufficient alone. The different (in)fertile phenotypes associated with it, a fertile father opposed to his two infertile sons, can be possibly influenced by genetic background, environmental and epigenetic factors, contributing to different phenotypic expressions of individual/specific genomes
Trends and Challenges for Quality of Service and Quality of Experience for Wireless Mesh Networks
Reproducción experimental de cromatosis en conejos por medio del suministro de la planta mamei-tomatillo (Bunchosia pseudomitida).
Se realizaron dos experimentos que consistieron en el suministro de 5 a 20 gr diarios de la planta mamei-tomatillo o pateperro (Bunchosia pseudonitida) a 15 conejos con el fín de conocer los efectos que aquella puediera tener sobre éstos y establecer una posible relación con la cromatosis en bovinos y ovinos de los departamentos del Huila y Tolima(Colombia). Los conejos presentaron síntomas, signos y lesiones similares a los observados en casos de ocurrencia natural de Cromatosis tales como pigmentación rosada de los dientes y eliminación de orina pigmentada luego de consumo diario de 15 gr de planta verde por un período de 10 a 15 días. En animales con consumo mayor de 9 gr por período de 60 días, se observó pigmentación rosada en tejidos subcutáneos, fascias, superficies de músculos y órganos que tuviesen tejido elástico, además se estableció un retardo en el incremento de peso en los grupos de conejos que consumieron mayor cantidad de la planta en experimentación. Por los resultados obtenidos se deduce que la planta mamei-tomatillo o pateperro (Bunchosia pseudonitida) está directamente relacionada con la entidad patológica conocida como Cromatosis o vaca moradaCunicultura-Conejo (oryctolagus) - Oryctolagus Cuniculo
Flexible triangular formation keeping of marine robotic vehicles using range measurements.
This paper addresses the problem of keeping an autonomous marine vehicle in a moving triangular formation by regulating its position with respect to two leader vehicles. The follower vehicle has no prior knowledge of the path described by the leaders but has access to their heading angle and is able to measure inter-vehicle ranges. It is assumed that the distance between the leaders is constant and known. A control strategy is adopted that generates speed and heading commands so as to drive suitably defined along track and cross track errors to zero. The commands are used as input to local inner loops for yaw and speed control. The paper describes the algorithms derived for range-based control and assesses their performance in simulations using realistic models of the vehicles involved. Tests with three autonomous marine vehicles equipped with acoustic modems and ranging devices allow for the evaluation of the performance of the algorithms in a real-world situation
Revisiting niche fundamentals with Tukey depth
1. The first attempts to describe species ecological niches were simple geometric procedures that depict the niche boundaries directly from environmental data. The convex hull was one of such procedures, popular for its simplicity, clear ecological rational and precise definition of the niche. However, it lacked the ability to differentiate areas of the niche with different probabilities of occurrence according to environmental suitability. 2. We incorporate the Tukey depth, a mathematical tool to measure the centrality of a point within a cloud of points on a multidimensional space, in the convex hull approach to (i) propose a new procedure (CH-Tukey) to estimate species’ environmental suitability, and (ii) estimate niche overlap coherently. In addition to a clear ecological rational and simplicity the CHTukey procedure has a number of attractive features: use of presence-only data; independence from background data; invariance to scale; robustness to outliers; and the decomposition of the niche into a finite number of isosuitability levels, permitting the computation of consistent overlap indices. We illustrate the use of CH-Tukey, using occurrence data of the main Quercus species and subspecies from Western Mediterranean Europe, comparing its outputs with BIOCLIM and MAXENT. 3. Results showed distinct niche geometries among the different approaches. BIOCLIM produced rectilinear niches reflecting the assumption that ecological variables are independent in their action on the species. CHTukey, relaxing this assumption, adjusts niche outer boundary and the inner suitability levels to the known occurrences. MAXENT produced unbounded niche geometries, showing abrupt shifts in the species response to the environmental variables. 4. The niche predictions obtained with geometric approaches, BIOCLIM and CH Tukey, are simpler but better aligned with Hutchinson’s niche concept than those obtained with MAXENT, this latter showing ecologically implausible relationships with the environmental variables. CH-Tukey and the related overlap measures provide an adequate tool to explore niche properties and species-environment relationships
The automatic detection subsystem
Marques, M. M., Lobo, V., Aguiar, A. P., Silva, J. E., de Sousa, J. B., Nunes, M. D. F., Ribeiro, R. A., Bernardino, A., Cruz, G., & Marques, J. S. (2021). An unmanned aircraft system for maritime operations: The automatic detection subsystem. Marine Technology Society Journal, 55(1), 38-49. https://doi.org/10.4031/MTSJ.55.1.4 --- This work was funded by POFC (Programa Operacional Factores de Competitividade) within the National Strategic Reference Framework (QREN) under grant agreement 2013/034063 (SEAGULL, Project Number 34063).This paper addresses the development of an integrated system to support maritime situation awareness based on unmanned aerial vehicles (UAVs), empha-sizing the role of the automatic detection subsystem. One of the main topics of research in the SEAGULL project was the automatic detection of sea vessels from sensors onboard the UAV, to help human operators in the generation of situational awareness of maritime events such as (a) detection and geo-referencing of oil spills or hazardous and noxious substances, (b) tracking systems (e.g., vessels, ship-wrecks, lifeboats, debris), (c) recognizing behavioral patterns (e.g., vessels rendez-vous, high-speed vessels, atypical patterns of navigation), and (d) monitoring environmental parameters and indicators. We describe a system composed of optical sensors, an embedded computer, communication systems, and a vessel detection algorithm that can run in real time in the embedded UAV hardware and provide to human operators vessel detections with low latency, high precision rates (about 99%), and suitable recalls (>50%), which is comparable to other more computationally intensive state-of-the-art approaches. Field test results, including the detection of lifesavers and multiple vessels in red-green-and-blue (RGB) and thermal images, are presented and discussed.publishersversionpublishe
The contribution of small shrubby patches to the functional diversity of wood-pastures
Wood-pastures are grazed systems resulting from a long-term use of natural woodlands by humans. These social-ecological systems, covering vast areas of Europe and other temperate regions, have both high biodiversity and economic values, so many are classified as High Nature Value Farmlands. However, in some regions a loss of spatial heterogeneity threatens this natural value. We investigated the potential contribution of tiny shrubby patches to increase spatial heterogeneity and functional diversity in wood-pasture landscapes. Specifically, we compared functional composition (Community Weighted Means) and functional diversity (Functional Dispersion and Functional Evenness) of assemblages of plants, beetles and lichens in those patches (252-3000 m(2)) and in the wood-pasture matrix. We found that shrubby patches and matrix harbour species assemblages with very distinct functional compositions in all studied taxonomic groups. Evergreen, woody, broad-leafed and fleshy-fruited are better represented in the patches. In beetles, the main differences were a greater prevalence of small-sized and fungivore species in the patches. Shrubby patches also mostly harboured lichens with fruticose- and foliose-broad growth forms, a greater humidity preference, and lower eutrophication tolerance. Moreover, the two indexes used to quantify functional diversity (Functional Dispersion and Functional Evenness) show that, overall, diversity is greater in patches than in the matrix; in patches Functional Dispersion is statistically higher for plants, and Evenness is statistically higher for beetles and lichen. These differences are all consistent with the very distinct ecological conditions in the matrix and patches. The greater overall functional diversity of shrubby patches, and the major differences in functional composition between patches and matrix, observed for all taxa, indicate that these patches greatly enhance the functional diversity of species assemblages in wood-pasture landscapes. Consequently, preserving and promoting tiny shrubby patches is a potentially valuable low-cost management tool to increase biodiversity and improve ecosystem functioning in wood-pasture landscapes.Peer reviewe
Unraveling the pathogenesis of ARX polyalanine tract variants using a clinical and molecular interfacing approach
The Aristaless-related homeobox (ARX) gene is implicated in intellectual disability with the most frequent pathogenic mutations leading to expansions of the first two polyalanine tracts. Here, we describe analysis of the ARX gene outlining the approaches in the Australian and Portuguese setting, using an integrated clinical and molecular strategy. We report variants in the ARX gene detected in 19 patients belonging to 17 families. Seven pathogenic variants, being expansion mutations in both polyalanine tract 1 and tract 2, were identifyed, including a novel mutation in polyalanine tract 1 that expands the first tract to 20 alanines. This precise number of alanines is sufficient to cause pathogenicity when expanded in polyalanine tract 2. Five cases presented a probably non-pathogenic variant, including the novel HGVS: c.441_455del, classified as unlikely disease causing, consistent with reports that suggest that in frame deletions in polyalanine stretches of ARX rarely cause intellectual disability. In addition, we identified five cases with a variant of unclear pathogenic significance. Owing to the inconsistent ARX variants description, publications were reviewed and ARX variant classifications were standardized and detailed unambiguously according to recommendations of the Human Genome Variation Society. In the absence of a pathognomonic clinical feature, we propose that molecular analysis of the ARX gene should be included in routine diagnostic practice in individuals with either nonsyndromic or syndromic intellectual disability. A definitive diagnosis of ARX-related disorders is crucial for an adequate clinical follow-up and accurate genetic counseling of at-risk family members.Unit for Multidisciplinary Research in Biomedicine, UMIB, ICBAS-UP, Porto, Portugal was funded by FEDER funds of the Operational Program for Competitiveness Factors – COMPETE through FCT – Foundation for Science and Technology under the project: Fcomp-01-0124-FEDER-015896. The Neurogenetics research program in the Department of Paediatrics, University of Adelaide, Australia was funded by the Australian National Health and Medical Research Council (Grant No. 1063025). C. S. is supported Australian Research Council (Future Fellowship FT120100086
A validação da distribuição de espécies através de modelos preditivos: casos de estudo para a ilha da madeira
Os modelos preditivos de distribuição de espécies são uma importante ferramenta para lidar com a falta de informação biogeográfica existente para a maior parte dos taxa. Com esta técnica, estabelece -se uma relação entre a variável dependente (presença/ausência de uma espécie) e um conjunto de variáveis potencialmente preditoras, e é criado um mapa com a probabilidade de presença da espécie para uma determinada área de interesse. Neste capítulo, é usado o programa Maxent para criar modelos de distribuição potencial de um conjunto seleccionado de espécies, e os resultados obtidos são discutidos com base no conhecimento de especialistas nessas espécies.ABSTRACT: Predictive models of species distribution emerge as a valuable tool for tackling the lack of distributional information on most taxa. A function between the dependente variable (presence/absence of the species) and a set of potential predictors is established, and a map is generated for the focus area, indicating the probability of presence of the species. In this chapter, we use Maxent to develop potential distribution models for a number of selected species and we discuss the results on the basis of expert knowledge
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