Complex identification of plants from leaves

Se presenta una propuesta para el reconocimiento de hojas muy semejantes en su apariencia.The automatic identification of plant leaves is a very important current topic of research in vision systems. Several researchers have tried to solve the problem of identification from plant leaves proposing various techniques. The proposed techniques in the literature have obtained excellent results on data sets where the leaves have dissimilar features to each other. However, in cases where the leaves are very similar to each other, the classification accuracy falls significantly. In this paper, we proposed a system to deal with the performance problem of machine learning algorithms where the leaves are very similar. The results obtained show that combination of different features and features selection process can improve the classification accuracy

Soil fragmentation study applying different tillage systems

Runoff generation depends on rainfall, infiltration, interception, and surface depressional storage. Surface depressional storage depends on surface microtopography, usually quantified trough soil surface roughness (SSR). SSR is subject to spatial and temporal changes that create a high variability. In an agricultural environment, tillage operations produce abrupt changes in roughness. Subsequent rainfall gradually decreases roughness. Beside it, local variation in soil properties and hydrology cause its SSR to vary spatially at different scales. The methods commonly used to measure it involve collecting point elevations in regular grids using laser profilers or scanners, digital close range stereo-photogrammetry and terrestrial laser scanning or LIDAR systems. In this case, a laser-scanning instrument was used to obtain representative digital elevation models (DEMs) at a grid resolution of 7.2x7.2mm that cover an area of 0.9x0.9m. The DEMs were obtained from two study sites with different soils. The first study site was an experimental field on which five conventional tillage methods were applied. The second study site was a large olive orchard with trees planted at 7.5x5.0m and bare soils between rows. Here, three tillage treatments were applied. In this work we have evaluated the spatial variability of SSR at several scales studying differences in height calculated from points separated by incremental distances h were raised to power values q (from 0 to 4 in steps of 0.1). The q = 2 data were studied as a semivariogram model. The logarithm of average differences plotted vs. log h were characterized by their slope, ?(q). Structure functions [?(q) vs. q] were fitted showing that data had nonlinear structure functions typical of multiscale phenomena. Comparisson of the two types of soil in their respective structure functions are shown

Tinea nigra palmaris : a clinical case in a rural Ethiopian hospital

Tinea nigra is an infrequent, superficial fungal infection, mainly caused by Hortaea werneckii, which is still underreported in Ethiopia. An asymptomatic 62-year-old male patient sought a rural hospital of Ethiopia, showing dark plaques on the palms of both hands. A superficial mycosis was suspected and a direct light microscopic mycological examination from skin scrapings revealed short brownish hyphae. To our knowledge, this is the first case of tinea nigra from the Ethiopian highlands. This may be due to the actual rarity of the condition or to underreporting.Peer reviewe

Influence of tillage on soil surface roughness structure andsurface porosity.

Soil erosion is a complex phenomenon involving the detachment and transport of soil particles, storage and runoff of rainwater, and infiltration. The relative magnitude and importance of these processes depends on several factors being one of them surface microtopography, usually quantified trough soil surface roughness (SSR). Surface soil porosity and SSR can be altered by tillage operation. Even though the surface porosity is an important parameter of a tilled field, however, no practical technique for rapid and non-contact measurement of surface porosity has been developed yet

Isocost Lines Describe the Cellular Economy of Genetic Circuits

Genetic circuits in living cells share transcriptional and translational resources that are available in limited amounts. This leads to unexpected couplings among seemingly unconnected modules, which result in poorly predictable circuit behavior. In this study, we determine these interdependencies between products of different genes by characterizing the economy of how transcriptional and translational resources are allocated to the production of proteins in genetic circuits. We discover that, when expressed from the same plasmid, the combinations of attainable protein concentrations are constrained by a linear relationship, which can be interpreted as an isocost line, a concept used in microeconomics. We created a library of circuits with two reporter genes, one constitutive and the other inducible in the same plasmid, without a regulatory path between them. In agreement with the model predictions, experiments reveal that the isocost line rotates when changing the ribosome binding site strength of the inducible gene and shifts when modifying the plasmid copy number. These results demonstrate that isocost lines can be employed to predict how genetic circuits become coupled when sharing resources and provide design guidelines for minimizing the effects of such couplings.United States. Air Force Office of Scientific Research (Grant FA9550-14-1-0060)United States. Defense Advanced Research Projects Agency (Contract W911NF-12-1-0540)National Institutes of Health (U.S.) (Grant P50 GM098792

Tinea nigra palmaris: a clinical case in a rural Ethiopian hospital

Tinea nigra is an infrequent, superficial fungal infection, mainly caused by Hortaea werneckii, which is still underreported in Ethiopia. An asymptomatic 62-year-old male patient sought a rural hospital of Ethiopia, showing dark plaques on the palms of both hands. A superficial mycosis was suspected and a direct light microscopic mycological examination from skin scrapings revealed short brownish hyphae. To our knowledge, this is the first case of tinea nigra from the Ethiopian highlands. This may be due to the actual rarity of the condition or to underreportin

Cytokinin Determines Thiol-Mediated Arsenic Tolerance and Accumulation

The presence of arsenic in soil and water is a constant threat to plant growth in many regions of the world. Phytohormones act in the integration of growth control and stress response, but their role in plant responses to arsenic remains to be elucidated. Here, we show that arsenate [As(V)], the most prevalent arsenic chemical species in nature, causes severe depletion of endogenous cytokinins (CKs) in the model plant Arabidopsis (Arabidopsis thaliana). We found that CK signaling mutants and transgenic plants with reduced endogenous CK levels showed an As(V)-tolerant phenotype. Our data indicate that in CK-depleted plants exposed to As(V), transcript levels of As(V)/phosphate-transporters were similar or even higher than in wild-type plants. In contrast, CK depletion provoked the coordinated activation of As(V) tolerance mechanisms, leading to the accumulation of thiol compounds such as phytochelatins and glutathione, which are essential for arsenic sequestration. Transgenic CK-deficient Arabidopsis and tobacco lines show a marked increase in arsenic accumulation. Our findings indicate that CK is an important regulatory factor in plant adaptation to arsenic stress

Development of an in vitro periodontal biofilm model for assessing antimicrobial and host modulatory effects of bioactive molecules

Background: Inflammation within the oral cavity occurs due to dysregulation between microbial biofilms and the host response. Understanding how different oral hygiene products influence inflammatory properties is important for the development of new products. Therefore, creation of a robust host-pathogen biofilm platform capable of evaluating novel oral healthcare compounds is an attractive option. We therefore devised a multi-species biofilm co-culture model to evaluate the naturally derived polyphenol resveratrol (RSV) and gold standard chlorhexidine (CHX) with respect to anti-biofilm and anti-inflammatory properties.<p></p> Methods: An in vitro multi-species biofilm containing <i>S. mitis, F. nucleatum, P. Gingivalis</i> and <i>A. Actinomycetemcomitans</i> was created to represent a disease-associated biofilm and the oral epithelial cell in OKF6-TERT2. Cytotoxicity studies were performed using RSV and CHX. Multi-species biofilms were either treated with either molecule, or alternatively epithelial cells were treated with these prior to biofilm co-culture. Biofilm composition was evaluated and inflammatory responses quantified at a transcriptional and protein level.<p></p> Results: CHX was toxic to epithelial cells and multi-species biofilms at concentrations ranging from 0.01-0.2%. RSV did not effect multi-species biofilm composition, but was toxic to epithelial cells at concentrations greater than 0.01%. In co-culture, CHX-treated biofilms resulted in down regulation of the inflammatory chemokine IL-8 at both mRNA and protein level. RSV-treated epithelial cells in co-culture were down-regulated in the release of IL-8 protein, but not mRNA.<p></p> Conclusions: CHX possesses potent bactericidal properties, which may impact downstream inflammatory mediators. RSV does not appear to have bactericidal properties against multi-species biofilms, however it did appear to supress epithelial cells from releasing inflammatory mediators. This study demonstrates the potential to understand the mechanisms by which different oral hygiene products may influence gingival inflammation, thereby validating the use of a biofilm co-culture model.<p></p&gt

DIMENSIONAMIENTO DE CRISTALES DE AZÚCAR A PARTIR DE PROCESAMIENTO DE IMÁGENES (SIZING OF SUGAR CRYSTALS BY IMAGE PROCESSING)

Resumen En este trabajo se determinaron las áreas superficiales y los volúmenes de cristales de azúcar capturados en un microscopio. El área superficial se determina a partir del análisis de imágenes, para ello se determinan los bordes de los cristales que se muestren completos y ortorrómbicos en la pantalla. Con la determinación de las áreas de los cristales se crea una relación dentro del programa para generar el valor del volumen. El procesamiento aquí mostrado puede ser empleado en línea o procesando un video pregrabado. En este caso, para grabar se utilizó un celular que grababa a través de la mirilla de un microscopio mientras los cristales pasabas por una celda de cristal. El análisis cuenta con un error del 0.8016% en comparación al método mie, utilizado en un MasterSizer. Palabras clave: Procesamiento imagen, cristales, dimensionamiento. Abstract In this work, the surface areas and volumes of sugar crystals captured under a microscope were determined. The surface area is determined from image analysis by determining the edges of the crystals that appear complete and orthorhombic on the screen. With the determination of the crystal areas a relation is created within the program to generate the volume value. The processing shown here can be employed online or by processing a pre-recorded video. In this case, a cell phone was used to record through a microscope scope while the crystals were passing through a crystal cell. The analysis has an error of 0.8016% compared to the mie method used in MasterSizer. Keywords: Image processing, crystals, sizing.>/em

Diagnóstico precoz del VIH en atención primaria en España. Resultados de una prueba piloto de cribado dirigido basado en condiciones indicadoras, criterios conductuales y de origen

Estimar la prevalencia de la infección por VIH en pacientes diagnosticados con una condición indicadora (CI) para el VIH y/o que habían tenido una conducta de riesgo para su adquisición y/o que provenían de países con elevada prevalencia. Determinar la aceptabilidad y viabilidad de ofrecer la prueba del VIH basada en CI y criterios conductuales y de origen en atención primaria (AP). Estudio transversal en una muestra de conveniencia. Seis centros de AP en España. Los criterios de inclusión fueron: pacientes entre 16 y 65 años que presentaban al menos una de las CI propuestas y/o al menos uno de los criterios conductuales y/o de origen propuestos. Participaron 388 pacientes. Se ofreció la serología del VIH a todos los pacientes que cumplían con los criterios de inclusión. Descripción de la frecuencia de CI, criterios conductuales y de origen. Prevalencia de infección por VIH. Nivel de aceptabilidad y viabilidad de la oferta de la prueba del VIH basada en criterios conductuales y de origen y CI. Un total de 174 pacientes presentaron una CI (44,84%). El criterio conductual más común fue: haber mantenido relaciones sexuales desprotegidas alguna vez en la vida con personas que desconocían su estado serológico para el VIH (298; 76,8%). Se diagnosticaron 4 pacientes VIH+ (1,03%). Todos presentaban una CI y eran hombres que mantenían sexo con hombres. El nivel de aceptabilidad en AP fue elevada. Ofrecer la prueba del VIH a pacientes con CI y criterios conductuales es viable y efectiva en AP