545 research outputs found
Avaliação de cultivares de soja em duas épocas de semeadura, no município de Bataiporã, MS, safra 1998/99.
bitstream/item/39756/1/COT-12-1999.pd
Época de semeadura: um importante fator que afeta a produtividade da cultura da soja.
Temperatura do ar; Umidade do solo; Fotoperíodo.bitstream/item/65720/1/DOC34.pd
Remote landslide mapping using a laser rangefinder binocular and GPS
We tested a high-quality laser rangefinder binocular coupled with a GPS receiver connected to a Tablet PC running dedicated software to help recognize and map in the field recent rainfall-induced landslides. The system was tested in the period between March and April 2010, in the Monte Castello di Vibio area, Umbria, Central Italy. To test the equipment, we measured thirteen slope failures that were mapped previously during a visual reconnaissance field campaign conducted in February and March 2010. For reference, four slope failures were also mapped by walking the GPS receiver along the landslide perimeter. Comparison of the different mappings revealed that the geographical information obtained remotely for each landslide by the rangefinder binocular and GPS was comparable to the information obtained by walking the GPS around the landslide perimeter, and was superior to the information obtained through the visual reconnaissance mapping. Although our tests were not exhaustive, we maintain that the system is effective to map recent rainfall induced landslides in the field, and we foresee the possibility of using the same (or similar) system to map landslides, and other geomorphological features, in other areas
Landslide mapping from multi-sensor data through improved change detection-based Markov random field
Abstract Accurate landslide inventory mapping is essential for quantitative hazard and risk assessment. Although multi-temporal change detection techniques have contributed greatly to landslide inventory preparation, it is still challenging to generate quality change detection images (CDIs) for accurate landslide mapping. The recently proposed change detection-based Markov random field (CDMRF) provides an effective approach for rapid mapping of landslides with minimum user interventions. However, when CDI is generated by change vector analysis (CVA) alone, the CDMRF method may suffer from noise especially when the pre- and post-event remote sensing images are acquired under different atmospheric, illumination, and phenological conditions. This paper improved such CDMRF approach by integrating normalized difference vegetation index (NDVI), principal component analysis (PCA), and independent component analysis (ICA) generated CDIs with MRF for landslide inventory mapping from multi-sensor data. To justify the effectiveness and applicability, the improved methods were applied to map rainfall-, typhoon-, and earthquake-triggered landslides from the pre- and post-event satellite images acquired by very high resolution QuickBird, high resolution FORMOSAT-2, and moderate resolution Sentinel-2. Moreover, they were tested on pre-event Landsat-8 and post-event Sentinel-2 datasets, indicating that they are operational for landslide inventory mapping from combined multi-temporal and multi-sensor data. The results demonstrate that the improved δNDVI-, PCA-, and ICA-based approaches perform much better than CVA-based CDMRF in terms of completeness, correctness, Kappa coefficient, and F-measures. To the best of our knowledge, it is the first time that NDVI, PCA, and ICA are integrated with MRF for landslide inventory mapping from multi-sensor data. It is anticipated that this research can be a starting point for developing new change detection techniques that can readily generate quality CDI and for applying advanced machine learning algorithms (e.g., deep learning) to automatic detection of natural hazards from multi-sensor time series data
Receiver operating characteristic (ROC) curves to identify birth weight cutoffs to predict overweight in Mexican school children
OBJETIVO: Identificar pontos de corte do peso ao nascer na predição do excesso de peso em crianças e adolescentes mexicanos em idade escolar da cidade de Chilpancingo, México, em 2004. MÉTODOS: Seiscentos e sessenta e dois escolares de ambos os sexos, entre 5 e 13 anos, foram selecionados por amostragem probabilística, com partilha proporcional ao tamanho. Medidas do peso ao nascer foram extraídas das carteiras de vacinação. Para a classificação do estado nutricional, utilizaram-se pontos de corte do índice de massa corporal (IMC) segundo idade e sexo. Equações de predição foram construídas utilizando-se modelos de regressão linear. Áreas sob as curvas ROC (receiver operating characteristic) foram calculadas e curvas ROC de dois gráficos (TG-ROC) foram construídas, respectivamente, para detecção da acurácia global e identificação de pontos de corte do peso ao nascer, correspondentes à intersecção das curvas de sensibilidade e especificidade. RESULTADOS: Entre as crianças, a prevalência de excesso de peso foi maior no sexo feminino (46%) que no masculino (38,5%); entre adolescentes, as respectivas prevalências foram de 43,5 e 38,9%. O IMC médio e os decis de peso ao nascer apresentaram relação linear. As áreas sob as curvas ROC apresentaram valores > 78% em cada estrato, detectando-se diferença, em relação ao sexo, no grupo de adolescentes. As curvas TG-ROC apresentaram pontos de corte do peso ao nascer mais elevados nos meninos que nas meninas, e as intersecções das curvas de sensibilidade e especificidade foram > 0,70. CONCLUSÕES: Os resultados do estudo indicaram que pontos de corte do peso ao nascer podem ser utilizados como marcadores de excesso de peso, na infância e adolescência, constituindo-se em estratégia para o rastreamento de grupos de risco.OBJECTIVE: To identify birth weight cutoffs to predict overweight in school children and adolescents from Chilpancingo, Mexico, in 2004. METHODS: Six hundred and sixty-two male and female children between 5 and 13 years old were selected by probability sampling. Birth weight measures were extracted from vaccination cards. The school children's nutritional status was defined using specific body mass index (BMI) cutoffs according to sex and age. Predicting equations were built using linear regression models. Areas under the receiver operating characteristic (ROC) curves were calculated and two-graph (TG) ROC curves were plotted, respectively, to detect global accuracy and to identify birth weight cutoffs corresponding to the intersection of sensitivity and specificity curves. RESULTS: Overweight prevalence was higher in female (46%) than in male school children (38.5%). Among adolescents, the prevalence of overweight was also higher in females (43.5%) than in males (38.9%). BMI average and birth weight deciles showed a linear relation. Areas under ROC curves showed values > 78% in each stratum of sex and age, depicting a difference by sex in adolescents. TG-ROC curves showed that birth weight cutoffs were slightly higher in boys than in girls, and the sensitivity/specificity intersections were > 0.70. CONCLUSIONS: The study results showed that birth weight cutoffs can be used as overweight markers in childhood and adolescence, being useful as a screening strategy to detect risk groups
Toward the use of temporary tattoo electrodes for impedancemetric respiration monitoring and other electrophysiological recordings on skin
The development of dry, ultra-conformable and unperceivable temporary tattoo electrodes (TTEs), based on the ink-jet printing of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on top of commercially available temporary tattoo paper, has gained increasing attention as a new and promising technology for electrophysiological recordings on skin. In this work, we present a TTEs epidermal sensor for real time monitoring of respiration through transthoracic impedance measurements, exploiting a new design, based on the application of soft screen printed Ag ink and magnetic interlink, that guarantees a repositionable, long-term stable and robust interconnection of TTEs with external “docking” devices. The efficiency of the TTE and the proposed interconnection strategy under stretching (up to 10%) and over time (up to 96 h) has been verified on a dedicated experimental setup and on humans, fulfilling the proposed specific application of transthoracic impedance measurements. The proposed approach makes this technology suitable for large-scale production and suitable not only for the specific use case presented, but also for real time monitoring of different bio-electric signals, as demonstrated through specific proof of concept demonstrators
A Bioinspired Plasmonic Nanocomposite Actuator Sunlight-Driven by a Photothermal-Hygroscopic Effect for Sustainable Soft Robotics
Combined photothermal-hygroscopic effects enable novel materials actuation strategies based on renewable and sustainable energy sources such as sunlight. Plasmonic nanoparticles have gained considerable interest as photothermal agents, however, the employment in sunlight-driven photothermal-hygroscopic actuators is still bounded, mainly due to the limited absorbance once integrated into nanocomposite actuators and the restricted plasmonic peaks amplitude (compared to the solar spectrum). Herein, the design and fabrication of an AgNPs-based plasmonic photothermal-hygroscopic actuator integrated with printed cellulose tracks are reported (bioinspired to Geraniaceae seeds structures). The nanocomposite is actuated by sunlight power density (i.e., 1 Sun = 100 mW cm−2). The plasmonic AgNPs are in situ synthesized on the PDMS surface through a one-step and efficient fluoride-assisted synthesis (surface coverage ≈40%). The nanocomposite has a broadband absorbance in the VIS range (>1) and a Photothermal Conversion Efficiency ≈40%. The actuator is designed exploiting a mechanical model that predicted the curvature and forces, featuring a ≈6.8 ± 0.3 s response time, associated with a ≈43% change in curvature and a 0.76 ± 0.02 mN force under 1 Sun irradiation. The plasmonic nanocomposite actuator can be used for multiple tasks, as hinted through illustrative soft robotics demonstrators, thus fostering a bioinspired approach to developing embodied energy systems driven by sunlight
Actualistic taphonomic study of the rodents digested by the Achala culpeo fox (Lycalopex culpaeus smithersi) in the highlands of central Argentina
We present the first actualistic study of the rodents consumed by the South American foxLycalopex culpaeus smithersi (Achala culpeo fox), a subspecies of the culpeo fox that is endemicto the highlands of central Argentina. We provide a taphonomic characterization of this canidbased on digested micromammal bones, and compare it to other carnivores. We studied over 1000bones derived from 83 scats collected in Quebrada del Condorito National Park, Córdobaprovince, Argentina, corresponding to caviomorph and myomorph rodents. Galea leucoblepharawas the main prey (59.8% MNI, 93.1% biomass). Average relative abundance for the totalassemblage was 26.7. Cranial and, to a lesser extent, proximal limb bones were the most abundantelements. A high degree of breakage was observed in cranial elements and, to a lesser extent, inlimb bones. A high proportion of heavy and extreme digestion was inferred, while some elementsbear light or no digestion traces at all. Overall, the Achala culpeo fox fits best with othermammalian carnivores in the category of extreme modification, and shows types and proportionsof taphonomic attributes similar to other South American mammalian predators. These resultscontribute to the understanding of regional taphonomic processes and of digestivemodifications by Lycalopex foxes generally, and are thus relevant to interpreting the presence of micromammal remains in the archaeological and palaeontological recordsand the impact of these foxes in their formation.Fil: Coll, Daiana Geraldine. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Montalvo, Claudia Inés. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Fernández, Fernando Julián. Universidad de Buenos Aires. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pia, Monica Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Mondini, Nora Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Antropología de Córdoba. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Instituto de Antropología de Córdoba; Argentin
A novel role of the interferon-inducible protein IFI16 as inducer of proinflammatory molecules in endothelial cells
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