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Community Ecology
Authors: A. García-Villaraco Velasco, A. Probanza, F. Gutierrez Mañero, B. Ramos, and J. Lucas García

Activity and functional diversity of rhizosphere bacterial communities and fungal composition were studied in order to assess the effects of different genotypes (N8035, N224 and N8637) of Arabidopsis thaliana on these communities growing in different soils. Genotype effect and soil effect were studied independently. Also, the interactions between both factors (genotypes and soils) were considered. The activity was determined by thymidine and leucine incorporation analysis, and Biolog ECO plates were used to study bacterial functional diversity. Additionally, fungi groups (genera and/or species) were studied in the different rhizospheres. Statistical differences on thymidine incorporation between plant genotypes were only found in two of the soils. In addition, functional diversity (measured by Shanonn-Weaver index), showed statistical differences only in soil 1 for line N8035 (line B) vs . the other lines. Redundancy analysis (RDA) performed with Biolog data indicated and important effect of soil type, but also an effect of genotype since line N8035 (line B) was separated from the other lines within each soil in the RDA ordination, in spite of genotypic differences between them were minimum. Furthermore, carboxylic acids and amino acids were found to be the Biolog plate substrates with more influence in samples ordination in the Redundancy Analysis (RDA). However, fungi seem to be less labile to plant selection than bacteria probably due to a lower turn-over time of fungi than bacteria coupled with the short phenology of Arabidopsis . In this paper, plant-soil-micro-organism relationships in the rhizosphere were studied, and the complex interactions between them were highlighted. More studies are necessary to go deep in these interactions and to be able to asses the impact of genetically modified plants.

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Abstract  

Trace metal advection and diffusion in natural porous and fractured materials have been investigated by using radiotracers. Three case studies are presented: 1) Se infiltration in granite cores in the presence of pyrite, 2) Co advection in quartz sand columns containing a layer of MnO2, and 3) Cr diffusion in clay. It is shown that the migration processes are controlled by surface mediated redox transformations.

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Summary Non-isothermal thermogravimetric data were used to evaluate the Arrhenius parameters (activation energy and the pre-exponential factor) of the combustion of two carbonaceous materials, selected as diesel soot surrogates. The paper reports on the application of model-free isoconversional methods (Flynn-Wall-Ozawa and Kissinger methods) for evaluating the activation energy of the combustion process. On the other hand, by means of the compensation relation between E and lnA, which was established by the model-dependent Coats-Redfern method, the value of the pre-exponential factor was estimated from the known value of the model-independent activation energy.

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The best alternative for reducing citrus production costs is mechanization. Machine vision is a reliable technology for the automatic inspection of fresh fruits and vegetables that can be adapted to harvesting machines. In these, fruits can be inspected before sending them to the packinghouse and machine vision provides important information for subsequent processing and avoids spending further resources in non-marketable fruit. The present work describes a computer vision system installed on a harvesting machine developed jointly by IVIA and a Spanish enterprise. In this machine, hand pickers directly drop the fruit as they collect it, which results in an important increase of productivity. The machine vision system is placed over rollers in order to inspect the produce, and separate those that can be directly sent to the fresh market from those that do not meet minimal quality requirements but can be used by the processing industry, based on color, size and the presence of surface damages. The system was tested under field conditions.

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The new Guettarda species of Oaxaca (Mexico) is related to G. foliacea Standl. of a distribution from Tabasco and Chiapas to Panama, but differs by having long acuminate and falcate leaves with lineolate quaternary nerves on the abaxial surface, inflorescences with very short ovate and glabrous bracteoles and much shorter flowers with 8–9 mm long corolla tube.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Perera, C. Perez, M. Torres, A. Henandez, F. Heres, T. Moreira, A. Gutierrez, A. Gigato, I. Hernandez, L. Alberti, O. Marrero, L. Martinez, J. Sanfiz, E. Sanchez, J. Rodriguez, L. Marrero, and G. Parra

Abstract  

The aim of this work was to obtain a freeze-dried kit for direct99mTc-labeling of human polyclonal IgG. The labeling procedure was carried out by Schwarz's method. The best yields of99mTc-IgG were obtained by using sodium pyrophosphate decahydrate as a weak chelating agent. Performed tests showed the stability of the radiopharmaceutical up to 24 hours. Plasma clearance in rats was fitted to a biexponential curve withT 1/2α=(0.1 ±0.9) h andT 1/2β=(10±3) h. The organs with higher uptake of radiopharmaceutical were lung, kidneys and blood. In a rabbit model the abscess target/background ratio was 3–6 according to time of the scintigraphic images. Thirty patients with musculoskeletal infection were studied. Twenty-one lesions were detected and confirmed by culture/biopsy.

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Journal of Behavioral Addictions
Authors: Guilherme Borges, Ricardo Orozco, Corina Benjet, Kalina I. Martínez Martínez, Eunice Vargas Contreras, Ana Lucia Jiménez Pérez, Alvaro Julio Peláez Cedrés, Praxedis Cristina Hernández Uribe, María Anabell Covarrubias Díaz Couder, Raúl A. Gutierrez-Garcia, Guillermo E. Quevedo Chavez, Yesica Albor, Enrique Mendez, Maria Elena Medina-Mora, Philippe Mortier, and Hans-Juergen Rumpf

Background and aims

DSM-5 includes Internet gaming disorder (IGD) as a condition for further study. While online and offline gaming may produce undesired negative effects on players, we know little about the nosology of IGD and its prevalence, especially in countries with emerging economies.

Methods

A self-administered survey has been employed to estimate prevalence of DSM-5 IGD and study the structure and performance of an instrument in Spanish to measure DSM-5 IGD among 7,022 first-year students in 5 Mexican universities that participated in the University Project for Healthy Students (PUERTAS), part of the World Health Organization’s World Mental Health International College Student Initiative.

Results

The scale for IGD showed unidimensionality with factor loadings between 0.694 and 0.838 and a Cronbach’s α = .816. Items derived from gaming and from substance disorders symptoms mixed together. We found a 12-month prevalence of IGD of 5.2% in the total sample; prevalence was different for males (10.2%) and females (1.2%), but similar for ages 18–19 years (5.0%) and age 20+ (5.8%) years. Among gamers, the prevalence was 8.6%. Students with IGD were more likely to report lifetime psychological or medical treatment [OR = 1.8 (1.4–2.4)] and any severe role impairment [OR = 2.4 (1.7–3.3)]. Adding any severe role impairment to the diagnostic criteria decreased the 12-month prevalence of IGD to 0.7%.

Discussion and conclusions

Prevalence of DSM-5 IGD and the performance of diagnostic criteria in this Mexican sample were within the bounds of what is reported elsewhere. Importantly, about one in every seven students with IGD showed levels of impairment that would qualify them for treatment under DSM-5.

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