GRASS in the Desert? Developing FOSS tools for monitoring desertification

The use of Change Vector Analysis (CVA) combined with the Tasselled Cap tranform (TCT) is a powerful remote sensing tool to monitor forests and vegetated areas, but its application to arid and semiarid environment is not straightforward. This question is tackled through the calculation of a new set of TCT coefficients using R and GRASS-GIS for SPOT and Landsat satellites, then applied and tested in change detection analysis on a short (seasonal) and a long (decades) temporal scale. Results show that the combined procedure is an effective method to detect changes in desert environment. Furthermore, the new TCT allows the use of this combined procedure for studies in arid and semi-arid regions, eliminating the doubts on its compatibility with the area of study. Further development is the creation of a new GRASS-GIS module to performe CVA, thus enabling the simple usage of this technique, until now not available in most common software

Solar Radiation Damage to Human Skin Mitochondria

The central objective of this study was to assess solar radiation-induced changes in cellular function, mitochondrial function and mitochondrial DNA to further investigate the role of these energy-dedicated and metabolically essential organelles in the response to the main environmental stressor associated with skin cancer initiation. An in vitro approach was chosen employing the human malignant melanoma (A375) and human amelanotic melanoma (C32) cells and the human spontaneously immortalized keratinocytes (HaCaT). A Q-Sun Solar Simulator was used to expose cells to low-level simulated solar radiation (SSR) as it provides a mimic of solar radiation that is environmentally relevant in the UV spectrum. Cell viability, apoptosis, DNA and protein content were analysed as cellular response end-points and they have been observed to change in a cell type-specific and time- dependent manner post SSR. Increases in mitochondrial genome number and mtDNA3895 were observed as an early response to low-dose SSR in human skin cells. The common deletion mtDNA4977t,h ough detected, did not directly increase in frequency with solar radiation exposure though the mtDNA3895 deletion, previously found to be associated with solar radiation exposure, was observed to be substantially increased in a cell-type and dose-dependent manner in skin cells post SSR. Impaired mitochondrial bioenergetics, dynamics and recycling may play a significant role in the melanoma tumour initiation and progression in humans post systematic solar radiation over-exposure. Furthermore the sensitive nature of the mitochondrial population of skin cells should not be underestimated as dynamic changes in their biology are evident even in cell populations that received low level irradiation of simulated solar radiation

Filogeografia comparativa e história demográfica de dois marsupiais da Mata Atlântica

A Mata Atlântica é um hotsopot de biodiversidade e tem sido foco de diversos trabalhos por ser considerada uma unidade biogeográfica complexa ainda pouco compreendida. Estudos de filogeografia comparativa vêm desempenhando importante papel no conhecimento biodiversidade, pois através da comparação entre diferentes táxons é possível investigar ligações fundamentais entre processos populacionais e padrões regionais de diversidade e biogeografia. Diante disso, foram inferidas e comparadas as histórias demográficas e biogeográficas de duas espécies de marsupiais da Mata Atlântica, Gracilinanus microtarsus e Marmosops incanus, a fim de descobrir como essas espécies responderam às mudanças ambientais de ao longo do tempo. Sequências dos genes mitocondriais citocromo b e D-loop foram utilizadas para a reconstrução de filogenias, redes de haplótipos e análises genéticas populacionais. Os resultados mostraram alta divergência genética em ambas as espécies, assim como forte estruturação geográfica, com a formação de grupos geograficamente coesos e similares entre as espécies. A distinção de haplótipos ao sul da Mata Atlântica também foi observada nas filogenias e é condizente com barreiras geográficas, como a Serra do Mar e o Rio Paraíba do Sul, por exemplo. Os clados intraespecíficos mais antigos tiveram origem no Neógeno, condizente com um período de mudanças climáticas e intensas atividades tectônicas, indicando que a estrutura genética das populações das duas espécies é resultado de processos que ocorreram muito antes do Pleistoceno. As flutuações no tamanho efetivo das populações de G. microtarsus e M. incanus foram distintas, principalmente a partir último interglacial há 130 mil anos atrás. Logo, os dados mostram que as alterações no ambiente ao longo do tempo geraram estruturas filogeográficas e demográficas similares nas duas espécies de marsupiais, resultantes de uma história biogeográfica comum na Mata Atlântica nos últimos 7 milhões de anos, enquanto alterações ambientais mais recentes afetaram somente a demografia das espécies. Ocorreu aumento no tamanho efetivo populacional de G. microtarsus durante o último período glacial enquanto M. incanus apresentou redução, o que está de acordo com as expectativas baseadas nas respostas ecológicas dessas espécies à redução e fragmentação do habitat

Reconfiguração de redes de distribuição de energia com geração distribuída empregando conceitos de redes elétricas inteligentes

As Redes Elétricas Inteligentes (REI), também conhecidas como Smart Grids, representam um avanço do sistema elétrico atual. O conceito básico das REIs é agregar inteligência à rede por meio de tecnologias de comunicação e de computação que permitam obter dados em tempo real para monitorar e controlar a rede de forma autônoma. A reconfiguração automática da rede é um exemplo de funcionalidade de uma REI. Ela consiste em empregar uma técnica de otimização que possibilite alterar a topologia da rede a partir da abertura e fechamento de chaves de manobra, permitindo isolar falhas e restaurar o fornecimento em situações de contingência, e melhorar o desempenho da rede em regime normal de operação. Este trabalho apresenta uma metodologia de reconfiguração de redes de distribuição de energia elétrica considerando a inserção de fontes de geração distribuída, visando melhorar os indicadores de serviço da rede. Além disso, é empregado um método de análise multicriterial denominado Analytic Hierarchy Process (AHP) para avaliar o grau de importância de cada indicador e para identificar as manobras de maior impacto na reconfiguração. A metodologia foi testada por meio de simulações em um modelo de rede real. A partir das técnicas empregadas foi possível obter uma melhoria considerável dos indicadores de serviço da rede e também avaliar a importância da geração distribuída

Yaw Rate and Sideslip Angle Control Through Single Input Single Output Direct Yaw Moment Control

Electric vehicles with independently controlled drivetrains allow torque vectoring, which enhances active safety and handling qualities. This article proposes an approach for the concurrent control of yaw rate and sideslip angle based on a single-input single-output (SISO) yaw rate controller. With the SISO formulation, the reference yaw rate is first defined according to the vehicle handling requirements and is then corrected based on the actual sideslip angle. The sideslip angle contribution guarantees a prompt corrective action in critical situations such as incipient vehicle oversteer during limit cornering in low tire-road friction conditions. A design methodology in the frequency domain is discussed, including stability analysis based on the theory of switched linear systems. The performance of the control structure is assessed via: 1) phase-plane plots obtained with a nonlinear vehicle model; 2) simulations with an experimentally validated model, including multiple feedback control structures; and 3) experimental tests on an electric vehicle demonstrator along step steer maneuvers with purposely induced and controlled vehicle drift. Results show that the SISO controller allows constraining the sideslip angle within the predetermined thresholds and yields tire-road friction adaptation with all the considered feedback controllers

Deep learning in edge: evaluation of models and frameworks in ARM architecture

The boom and popularization of edge devices have molded its market due to stiff compe tition that provides better functionalities at low energy costs. The ARM architecture has been unanimously unopposed in the huge market segment of smartphones and still makes a presence beyond that: in drones, surveillance systems, cars, and robots. Also, it has been used successfully for the development of solutions for chains that supply food, fuel, and other services. Up until recently, ARM did not show much promise for high-level compu tation, i.e., thanks to its limited RISC instruction set, it was considered power efficient but weak in performance compared to x86 architecture. However, most recent advancements in ARM architecture pivoted that inflection point up thanks to the introduction of embed ded GPUs with DMA into LPDDR memory boards. Since this development in boards such as NVIDIA TK1, NVIDIA Jetson TX1, and NVIDIA TX2, perhaps it finally be came feasible to study and perform more challenging parallel and distributed workloads directly on a RISC-based architecture. On the other hand, the novelty of this technology poses a fundamental question of whether these boards are gaining a meaningful ratio be tween processing power and power consumption over conventional architectures or if they are bound to have reached their limitations. This work explores the Parallel Processing of Deep Learning on embedded GPUs of NVIDIA Jetson TX2 to evaluate the question above comprehensively. Thus, it uses 4 ARM boards, with 2 Deep Learning frameworks, 7 CNN models, and one medium-sized dataset combined into six board settings to con duct experiments. The experiments were conducted under similar environments, all built from the source. Altogether, the experiments ran for a total of 4,804 hours and revealed a slight advantage for MxNet on GPU-reliant training and a PyTorch overall advantage in total execution time and power, but especially for CPU-only executions. The experi ments also showed that the NVIDIA Jetson TX2 already makes feasible some complex workloads directly on its SoC

Francia, los franceses y el champán en la canción de tango: construcciones simbólicas y políticas en la canción de tango.

International audienc

Host factors and early treatments to restrict paediatric HIV infection and early disease progression

open6noA body of evidence indicates that a threshold level of the virus is required to establish systemic and persistent HIV infection in the host and that this level depends on virus-host interactions. Mother-to-child transmission (MTCT) of HIV is the main source of paediatric HIV infection and occurs when the host's immune system is still developing. Thus, innate resistance and immunity, rather than adaptive immune response, may be the main drivers in restricting the establishment of HIV reservoirs and the long-lived persistence of HIV infection in infants. Genetic variations in HIV co-receptors and their ligands, as well as in Toll-like receptors and defensins, key elements of innate immunity, have been demonstrated to influence the risk of perinatal HIV infection and disease progression in HIV-infected infants. Early treatments with combined antiretroviral therapy (cART) restrict paediatric infection by reducing the level of the transmitted/infecting virus to below the threshold required for the onset of immune response to the virus and also significantly reduce HIV reservoirs. However, despite long periods with no signs and symptoms of HIV infection, all early cART-treated children who later discontinued cART had a rebound of HIV, except for one case in whom a period of viral remission occurred. Which parameters predict viral remission or viral rebound after cART discontinuation? Could early cART prevent rather than just reduce the establishment of viral reservoirs? And, if so, how? Answers to these questions are also important in order to optimise the use of early cART in infants at high risk of HIV infection.openGianesin, Ketty; Petrara, Raffaella; Freguja, Riccardo; Zanchetta, Marisa; Giaquinto, Carlo; DE ROSSI, AnitaGianesin, Ketty; Petrara, Raffaella; Freguja, Riccardo; Zanchetta, Marisa; Giaquinto, Carlo; DE ROSSI, Anit