Multilayer Complex Network Descriptors for Color-Texture Characterization

A new method based on complex networks is proposed for color-texture analysis. The proposal consists on modeling the image as a multilayer complex network where each color channel is a layer, and each pixel (in each color channel) is represented as a network vertex. The network dynamic evolution is accessed using a set of modeling parameters (radii and thresholds), and new characterization techniques are introduced to capt information regarding within and between color channel spatial interaction. An automatic and adaptive approach for threshold selection is also proposed. We conduct classification experiments on 5 well-known datasets: Vistex, Usptex, Outex13, CURet and MBT. Results among various literature methods are compared, including deep convolutional neural networks with pre-trained architectures. The proposed method presented the highest overall performance over the 5 datasets, with 97.7 of mean accuracy against 97.0 achieved by the ResNet convolutional neural network with 50 layers.Comment: 20 pages, 7 figures and 4 table

Manifestations faded gradually replacement of alfalfa ("Medicado sativa L.") by barley ("Hordeum vulgare L.") sprount in portions of Guinea pigs ("Cavia porcellus L.") in the stage of growth

El experimento fue conducido en el Centro de Producción de Cuyes de la Universidad Nacional de Huancavelica con el objetivo de evaluar la utilización de cuatro niveles (0, 25, 50 y 75%) de cebada hidropónica (CH) en substitución de la alfalfa en la alimentación de cuyes machos y hembras de la Línea Perú, en la fase de crecimiento, en número de 72, con 18 días de edad y 175 g de PV inicial medio confinados durante 42 días. Las raciones experimentales isoproteícas, fueron ofrecidos a los animales a voluntad y divididos en dos porciones (8 y 17 h). Fue utilizado el diseño experimental completamente aleatorizado y los tratamientos distribuidos en esquema factorial 2x4 (sexo x niveles de cebada hidropónica) con tres repeticiones por tratamiento, constituido cada unidad experimental por tres cuyes. Existió reducción lineal para machos en el consumo de MS en g/día y g/kg0.75 con el aumento de los niveles de substitución, este comportamiento también fue verificado para el consumo de PC (g/día). Hubo efecto cúbico para el consumo de PC por los cuyes hembras, en g/día, en g/kg0.75 y en %PV. La substitución de la alfalfa por la CH afectó la conversión alimenticia, cuyo comportamiento fue cuadrático y cúbico para machos y hembras, respectivamente. La CH influyó de forma cúbica sobre el peso final y ganancia de peso diario en los cuyes machos y hembras. Se concluye que es posible substituir la alfalfa por la CH hasta el nivel de 75% en cuyes hembras. El nivel de 25% de substitución proporciona las mejores ganancias de peso y pesos finales en cuyes machos y hembras en crecimiento, lo que pone de manifiesto el efecto positivo de la inclusión de la CH en la ración de cuyes en crecimiento.The experiment was conducted at the Center for Guinea Pig Production, National University of Huancavelica in order to evaluate the use of four levels (0, 25, 50 and 75%) of hydroponic barley (CH) in substitution of alfalfa in the feeding male and female guinea pigs of Peru line, in the growth phase, in number of 72, with 18 days of age and 175 g of initial PV means confined for 42 days. Isoproteic the experimental diets were offered ad libitum to the animals and divided in to two portions (8 and 17 h). It was used the completely randomized design and treatments distributed in factorial scheme 2x4 (sex x levels hydroponic barley) with three replicates per treatment, each experimental unit consists of three guinea pigs. Linear reduction existed for males MS consumption in g / g / day kg 0.75 with increasing substitution levels, this behavior was also verified for PC consumption (g / day). There was a cubic effect for consumption by the female guinea pigs PC in g / day, in g / kg0.75 and in % PV. The substitution of CH alfalfa affected by feed conversion, whose behavior was quadratic and cubic for males and females, respectively. The CH influenced cubical on final weight and daily weight gain in male and female guinea pigs. We conclude that it is possible to replace the CH alfalfa to the level of 75% in female guinea pigs. The level of 25% substitution provides the best weight gain and final weights in males and females growing guinea pigs, which shows the positive effect of the inclusion of CH in the ration of growing guinea pigs

Epidemiological and transmissibility analysis of influenza A(H1N1)v in a southern hemisphere setting: Peru

We present a preliminary analysis of 1,771 confirmed cases of influenza A(H1N1)v reported in Peru by 17 July including the frequency of the clinical characteristics, the spatial and age distribution of the cases and the estimate of the transmission potential. Age-specific frequency of cases was highest among school age children and young adults, with the lowest frequency of cases among seniors, a pattern that is consistent with reports from other countries. Estimates of the reproduction number lie in the range of 1.2 to 1.7, which is broadly consistent with previous estimates for this pandemic in other regions. Validation of these estimates will be possible as additional data become available

Estructura genética y poblacional de Bovinos Brown Swiss del INIA en Puno

El monitoreo de la estructura poblacional, la consanguinidad y el tamaño efectivo de la población, permite prevenir pérdidas de diversidad genética en las poblaciones bovinas, particularmente en poblaciones bajo procesos de selección Por lo anterior, su estudio es necesario para implementar de manera más integral los programas de selección. El objetivo del estudio fue describir la estructura genética y poblacional de bovinos de la raza Brown Swiss del INIA en Puno a 3824 m s n

Effects of grazing pressure on plant species composition and water presence on bofedales in the Andes mountain range of Bolivia

Bofedales are high-Andean peatland plant communities with high capacity for water retention, which are regarded as oases of biodiversity. These areas have great social and economic value for livestock grazing, which plays an important role in their vegetation dynamics. However, the effects of increased livestock pressure on vegetation composition and surface water have not yet been clarified. The goal of this study was to assess the impact of current grazing practices on bofedal vegetation, species diversity and function. Specifically, the study aimed to (1) quantify carrying capacity and stocking rate in grazed bofedales and (2) quantify the effects of grazing pressure on plant composition and the extents of bare soil and surface water. Biomass and stocking rate estimates for 25 bofedales along the Cordillera Real (Tropical Andes, Bolivia) showed that all bofedales were overgrazed (carrying capacity/stocking rate (CC/SR) <1). Regression analyses showed significant decreases in number of plant species, species dominance, diversity and percent surface water as CC/SR declined (p < 0.05). Bofedales are negatively affected by increased grazing pressure and potentially affected by changes in livestock species. These pressures, combined with land use changes and climate change, could result in long-term negative effects for the ecological functioning and sustainability of bofedales

Contribution analysis of a Bolivian innovation grant fund: mixing methods to verify relevance, efficiency and effectiveness

We used contribution analysis to verify the key assumption in the intervention logic of an innovation fund in Bolivia directed to economic farmer organisations to develop value-added activities. We focused the research on three sub-components of the intervention logic: relevance of the farmer groups for local economic development, effectiveness of the fund in strengthening these group, and efficiency of the grant allocation mechanism. We used a case-based comparative analysis to assess effectiveness: improved market access for members, strengthened organisational capacities and the capacity to pay organisational costs. We showed that the grants to already well-endowed organisations were particularly unsuccessful

Validation of reference genes for expression analysis in the salivary gland and the intestine of Rhodnius prolixus (Hemiptera, Reduviidae) under different experimental conditions by quantitative real-time PCR

<p>Abstract</p> <p>Background</p> <p><it>Rhodnius prolixus </it>is a blood-feeding insect that can transmit <it>Trypanosoma cruzi </it>and <it>Trypanosoma rangeli </it>to vertebrate hosts. Recently, genomic resources for invertebrate vectors of human pathogens have increased significantly, and <it>R. prolixus </it>has been one of the main species studied among the triatomines. However, the paucity of information on many of the fundamental molecular aspects of this species limits the use of the available genomic information. The present study aimed to facilitate gene expression studies by identifying the most suitable reference genes for the normalization of mRNA expression data from qPCR.</p> <p>Results</p> <p>The expression stability of five candidate reference genes (<it>18S </it>rRNA, <it>GAPDH</it>, β-actin, α-tubulin and ribosomal protein <it>L26</it>) was evaluated by qPCR in two tissues (salivary gland and intestine) and under different physiological conditions: before and after blood feeding and after infection with <it>T. cruzi </it>or <it>T. rangeli</it>. The results were analyzed with three software programs: geNorm, NormFinder and BestKeeper. All of the evaluated candidate genes proved to be acceptable as reference genes, but some were found to be more appropriate depending on the experimental conditions. <it>18S</it>, <it>GAPDH </it>and α-tubulin showed acceptable stability for studies in all of the tissues and experimental conditions evaluated. β-actin, one of the most widely used reference genes, was confirmed to be one of the most suitable reference genes in studies with salivary glands, but it had the lowest expression stability in the intestine after insect blood feeding. <it>L26 </it>was identified as the poorest reference gene in the studies performed.</p> <p>Conclusions</p> <p>The expression stability of the genes varies in different tissue samples and under different experimental conditions. The results provided by three statistical packages emphasize the suitability of all five of the tested reference genes in both the crop and the salivary glands with a few exceptions. The results emphasise the importance of validating reference genes for qRT-PCR analysis in <it>R. prolixus </it>studies.</p

How big is the potato (Solanum tuberosum L.) yield gap in Sub-Saharan Africa and why? A participatory approach.

According to potato experts from ten Sub-Saharan Africa (SSA) countries working together in a community of practice (CoP) over a 3-years period, potato farmers across SSA can increase their current annual production of 10.8 million metric tons by 140% if they had access to high quality seed along with improved management practices. This paper describes this innovative new methodology tested on potato for the first time, combining modelling and a comprehensive online survey through a CoP. The intent was to overcome the paucity of experimental information required for crop modelling. Researchers, whose data contributed to estimating model parameters, participated in the study using Solanum, a crop model developed by the International Potato Center (CIP). The first finding was that model parameters estimated through participatory modelling using experts’ knowledge were good approximations of those obtained experimentally. The estimated yield gap was 58 Mg ha-1, of which 35 corresponded to a research gap (potential yield minus research yield) and 24 to farmers’ gap (research yield minus farmer’s yield). Over a 6-month period, SurveyMonkey, a Web-based platform was used to assess yield gap drivers. The survey revealed that poor quality seed and bacterial wilt were the main yield gap drivers as perceived by survey respondents