692 research outputs found
3x2 Achievement Goals, Friendship and Affectivity in Physical Education: Age-Gender Differences
Se persiguen tres objetivos: (a) analizar las diferencias relativas a la edad y sexo en las metas de logro 3x2, metas de amistad, y afectividad en Educación Física, (b) estudiar las relaciones entre esas variables, y (c) explorar el valor predictivo de las metas de logro 3x2 y amistad sobre la afectividad. La muestra estuvo formada por 1610 alumnos (855 varones y 755 mujeres) de 10 a 17 años. Se realizaron MANOVAS, análisis univariados (Scheffé), y regresiones lineales. Los resultados mostraron un descenso significativo de las metas de logro (excepto aproximación-otro), metas de amistad y afecto positivo debido al desarrollo. Los varones puntuaron más alto las metas de aproximación-tarea, aproximación-otro, y evitación-otro. Las metas de aproximación-tarea y aproximación-amistad fueron los principales predictores positivos del afecto positivo. La franja de 13 a 14 años muestra una gran sensibilidad a los tres estándares de competencia de logro, competencia social e inestabilidad afectivaThe objectives of the study are three: (a) to analyze the differences related to age and sex in the 3x2 achievement goals, the friendship goals, and the affectivity in Physical Education, (b) to study the relationships between these variables, and c) to explore the predictive value of the 3x2 achievement goals and friendship on affectivity. The sample consisted of 1610 students (855 males and 755 females), aged between 10 and 17 years. MANOVAS, univariate analyzes (Scheffé), and linear regressions were performed. The results showed a significant decrease in achievement goals (except other-approach), friendship goals, and positive affect due to development. Males scored higher on task-approach, other-approach, and other-avoidance goals than women. Task-approach and friendship-approach were the main positive predictors of positive affect. The range of 13 to 14 years shows a great sensitivity to the three competences of achievement, social competence, and affective instabilit
Increasing crop richness and reducing field sizes provide higher yields to pollinator-dependent crops
Agricultural landscapes cover >60% of terrestrial landscapes. While biodiversity conservation and crop productivity have been seen as mutually exclusive options for a long time, recent research suggests that agricultural landscapes represent significant opportunities for biodiversity conservation outside of traditional protected areas. Here, we use a unique dataset that includes annual monitoring of 12,300 permanent 25-ha plots over two decades across Spain to assess how agricultural landscapes are changing over time. We focus particularly on landscape composition and configuration variables such as the diversity of crops grown within a landscape, average plot size or the cover of natural habitats and assess how changes to these variables affect the ability of agricultural landscapes to ensure high yields. We find potential synergistic strategies that are good for biodiversity conservation and can also lead to increasing crop yields. Specifically, we find that management practices that favour increasing biodiversity values such as maintaining small field sizes and high crop richness values at the landscape scale actually led to the greatest average yield values across 54 crops, 41% of which depend on pollinator activity for reproduction. Policy implications: While our analysis does not factor in economic costs and benefits, we show that synergy scenarios that are good for biodiversity conservation and crop productivity are possible, yet not as widespread as they could be. © 2022 The Authors. Journal of Applied Ecology © 2022 British Ecological Society.We thank Sergio Mancheño Losa from the Spanish Ministerio de Agricultura, Pesca y Ali‐mentación for his support in providing the data used in this paper and to all the staff members that made ESYRCE database possible. A.M. received funding from an Ikerbasque, Basque Foundation for Science Research Fellowship. Research was also supported by the Spanish State Research Agency through Maria de Maeztu Excellence Unit accreditation (MDM‐2017‐0714) and the Basque Government BERC Programme. We appreciate funding from BiodivERsA joint call for research proposals (under the BiodivScen ERA‐Net COFUND programme and with the funding organizations AEI, NWO, ECCyT and NSF)
Production of gaseous and liquid chemicals by aqueous phase reforming of crude glycerol: Influence of operating conditions on the process
The present work studies the influence of the temperature (200-240 °C), pressure (38-50 bar), glycerol concentration (10-50 wt.%) and mass of catalyst/ glycerol mass flow rate ratio (W/mglycerol = 10-40 g catalyst min/g glycerol) during the aqueous phase reforming (APR) of a glycerol solution obtained from the production of biodiesel. The operating conditions exerted a statistically significant influence on the reforming results. Specifically, the global glycerol conversion and the carbon converted into gas and liquid products varied as follows: 4-100%, 1-80% and 16-93%, respectively. The gas phase was made up of H2 (8-55 vol.%), CO2 (34-66 vol.%), CO (0-4 vol.%) and CH4 (6-45 vol.%). The liquid phase consisted of a mixture of alcohols (monohydric: methanol and ethanol; and polyhydric: 1, 2-propanediol, 1, 2-ethanediol, 2, 3-butanediol), aldehydes (acetaldehyde), ketones (C3-ketones: acetone and 2-propanone-1-hydroxy; C4-ketones: 2-butanone-3-hydroxy and 2-butanone-1-hydroxy; and cyclic ketones), carboxylic acids (acetic and propionic acids) and esters (1, 2, 3-propanetriol-monoacetate), together with unreacted glycerol and water. The relative amount (free of water and un-reacted glycerol) of these compounds in the liquid phase was as follows: monohydric alcohols: 4-47%, polyhydric-alcohols: 14-68%, aldehydes: 0-5%, C3-ketones: 2-33%, C4-ketones: 0-10%, ciclo-ketones: 0-6%, carboxylic acids: 2-43%, and esters: 0-46%. This process turned out to be highly customisable for the valorisation of crude glycerol for the production of either gaseous or liquid products. Gas production is favoured at a low pressure (39 bar), high temperature (238 °C), high W/mglycerol ratio (38 g catalyst min/g glycerol) and employing a 15 wt.% glycerol solution. A high pressure (45 bar), medium temperature (216 °C), medium W/mglycerol ratio (22 g catalyst min/g glycerol) and the feeding of a 16 wt.% glycerol solution favours the production of liquid products
An XMM-Newton view of FeK{\alpha} in HMXBs
We present a comprehensive analysis of the whole sample of available
XMM-Newton observations of High Mass X-ray Binaries (HMXBs) until August, 2013,
focusing on the FeK{\alpha} emission line. This line is a key tool to better
understand the physical properties of the material surrounding the X-ray source
within a few stellar radii (the circumstellar medium). We have collected
observations from 46 HMXBs, detecting FeK{\alpha} in 21 of them. We have used
the standard classification of HMXBs to divide the sample in different groups.
We find that: (1) FeK{\alpha} is centred at a mean value of 6.42 keV.
Considering the instrumental and fits uncertainties, this value is compatible
with ionization states lower than FeXVIII. (2) The flux of the continuum is
well correlated with the flux of the line, as expected. Eclipse observations
show that the Fe fluorescence emission comes from an extended region
surrounding the X-ray source. (3) FeK{\alpha} is narrow (width lower than
0.15keV), reflecting that the reprocessing material does not move at high
speeds. We attempt to explain the broadness of the line in terms of three
possible broadening phenomena: line blending, Compton scattering and Doppler
shifts (with velocities of the reprocessing material V=1000-2000 km/s). (4) The
equivalent hydrogen column (NH) directly correlates with the EW of FeK{\alpha},
displaying clear similarities to numerical simulations. It highlights the
strong link between the absorbing and the fluorescent matter. The obtained
results clearly point to a very important contribution of the donors wind in
the FeK{\alpha} emission and the absorption when the donor is a supergiant
massive star.Comment: Accepted for publication in A&A. 13 pages, 16 figures + Appendice
The use of straw mulch as a strategy to prevent extreme soil erosion rates in citrus orchard. A Rainfall simulation approach
Not only the Sahel (Haregeweyn et al., 2013), the deforested land (Borelli et al., 2013) the chinese Plateau are
affected by intense soil erosion rates (Zhao et al., 2013). Soil erosion affect agriculture land (Cerdà et al., 2009),
and citrus orchards are being seeing as one of the crops with the highest erosion rates due to the managements
that avoid the catch crops, weeds or litter. Example of the research carried out on citrus orchards is found in the
Mediterranean (Cerdà and Jurgensen, 2008; 2009; Cerdà et al., 2009a; 2009b; Cerdà et al., 2011; 2012) and in
China (Wu et al., 1997; Xu et al., 2010; Wang et al., 2011; Wu et al., 2011; Liu et al., 2011; Lü et al., 2011; Xu et
al., 2012), and they confirm the non sustainable soil losses measured. The land management in citrus plantations
results in soil degradation too (Lu et al., 1997; Lü et al., 2012; Xu et al., 2012). The use of cover crops to reduce
the soil losses (Lavigne et al., 2012; Le Bellec et al., 2012) and the use of residues such as dried citrus peel has
been found successful. There is a need to find new plants or residues to protect the soils on citrus orchards.
Agriculture produces a high amount of residues. The pruning can contribute with a valuable source of nutrients
and a good soil protection. The leaves of the trees, and some parts of the plants, once harvest can contribute to
reduce the soil losses. Due to the mechanization of the agriculture, and the reduction of the draft animals (mainly
horses, mules, donkeys and oxen) the straw is being a residue instead of a resource. The Valencia region is the
largest producer of citrus in Europe, and the largest exporter in the world. This citrus production region is located
in the eastern cost of Spain where we can find the rice production area of the l’Albufera Lagoon paddy fields,
the third largest production region in Spain. This means, a rice production region surrounded by the huge citrus
production region. There, the rice straw is not used in the paddy fields after harvesting and the straw is being as
a residue that damages the air quality when burnt, the water quality due to the decomposition and the methane
production, and is not accepted in the field by the farmers. This is a new problem as few years ago the rice straw
was use for animal feeding. Many attempts were developed in the last decade to remove and use the straw to avoid
fires and water pollution (Iranzo et al., 2004; Silvestre et al., 2013).
Our goal is to test if a residue such as the rice straw can be transformed as a resource: soil erosion control. Straw
has been seen as a very efficient to reduce the water losses in agriculture land (García Moreno et al., 2013), the
soil losses in fire affected land (Robichaud et al., 2013a; 2013b; Fernandez and Vega, 2014), and soil properties
(García Orenes et al., 2009; 2010; Jordán et al., 2010; García Orenes 2012).
Rainfall simulations under 55 mm h-1 rainfall intensity during one hour on 0,25 m2 plots were carried out on plots
paired plots: bare and covered with straw. The plots covered with straw had different straw mulch cover: from 10
to 100 % cover and from 0,005 g m2 to 300 g m2. The results show a positive effect of the straw cover that show
an exponential relation between the straw cover and weight with the sediment yield.
Acknowledgements
The research projects GL2008-02879/BTE, LEDDRA 243857 and RECARE supported this research
Non-line-of-sight transient rendering
The capture and analysis of light in flight, or light in transient state, has enabled applications such as range imaging, reflectance estimation and especially non-line-of-sight (NLOS) imaging. For this last case, hidden geometry can be reconstructed using time-resolved measurements of indirect diffuse light emitted by a laser. Transient rendering is a key tool for developing such new applications, significantly more challenging than its steady-state counterpart. In this work, we introduce a set of simple yet effective subpath sampling techniques targeting transient light transport simulation in occluded scenes. We analyze the usual capture setups of NLOS scenes, where both the camera and light sources are focused on particular points in the scene. Also, the hidden geometry can be difficult to sample using conventional techniques. We leverage that configuration to reduce the integration path space. We implement our techniques in a modified version of Mitsuba 2 adapted for transient light transport, allowing us to support parallelization, polarization, and differentiable rendering. © 2022 The Author(s
Medición del grado de resiliencia de los sustentos de los hogares y de la seguridad alimentaria en ambientes de riesgo etíopes
The purpose of this case study, conducted in Amhara region of Ethiopia, is to contribute to ef
forts to measuring and assessing resilience properties of household livelihoods constructed in the
risky environments. It provides new insights for assessing livelihood vulnerability and designing
resilience building programs in areas of protracted food crisis. Based on resilience theory as applied
to social-ecological systems with an application of Modern Portfolio Theory, we adapted and measure
the four properties of resilience to livelihood systems and tested the expected relationships between
system properties as predicted by resilience theory. Household livelihood systems exhibited the ex
pected pattern of increasing connectivity with increasing wealth (food income). Similarly, household
resilience to food insecurity improves with increasing diversity of livelihood options and diversity de
clines with increasing connectivity of the system. This study demonstrates the use of a set of metrics
for assessing resilience properties of household livelihoods based on key driving factors.Con este estudio de caso, realizado en la región de Amhara (Etiopía), se pretende contribuir a
los esfuerzos para medir y evaluar el grado de resistencia de los sustentos económicos de los hogares construidos en ambientes de riesgo. Así, se proporcionan nuevos conocimientos para evaluar la
vulnerabilidad de los medios de subsistencia y diseñar programas de fortalecimiento de la resiliencia
en áreas de crisis alimentaria prolongada. Basándonos en la teoría de la resiliencia aplicada a los
sistemas socioecológicos, y aplicando la teoría moderna de carteras, adaptamos y medimos las cuatro propiedades de la resiliencia a los sistemas de medios de subsistencia y probamos las relaciones
esperadas entre las propiedades predichas por la teoría de la resiliencia. Los sistemas de sustento
de los hogares exhibieron el patrón esperado de conectividad creciente con el aumento de la riqueza
(ingresos alimentarios). Del mismo modo, la resistencia de los hogares a la inseguridad alimentaria
mejora con el aumento de la diversidad de opciones de medios de subsistencia y la disminución de la
diversidad a partir del incremento de la conectividad del sistema. Este estudio muestra el uso de un
conjunto de métricas con el fin de evaluar las propiedades de resiliencia de los sustentos del hogar
basado en factores clave de conducción
Gender differences in neuromuscular, haematological, and urinary responses during padel matches
Research on the acute physiological response to a padel match is limited. The present study aimed to: (a) evaluate neuromuscular, urinary, and hematological responses after simulated padel competition (SC) and (b) analyze possible gender differences. In this study, 28 high-level padel players participated (men = 13, age = 26.83 ± 6.57 years; women = 15, age = 30.07 ± 4.36 years). The following parameters were analyzed before and after SC: neuromuscular (hand grip strength, squat jump (SJ), countermovement jump (CMJ), and Abalakov jump (ABK)), hematological (red blood cells, hemoglobin, and hematocrit), and urinary (pH, specific gravity, microalbuminuria, and red blood cells). Significant gender differences were found in neuromuscular and hematological responses, with men obtaining higher values (p < 0.05). For the SC influence, changes were noted in ABK and microalbuminuria (p < 0.05). The percentages of change in hand grip strength, SJ (height and watts), CMJ (height), and ABK (height) were higher for men than women (p < 0.05). SC negatively influenced the neuromuscular parameters to a greater extent in women. Our results could be related to gender differences in game actions, the temporal structure, and anthropometric and physiological characteristics. Game dynamics and a different organic response between male and female padel playing were confirmed. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
Caracterización energética de la unión de 1,3,6- naftalén trisulfonato al factor de crecimiento para fibroblastos ácido humano: implicaciones para su uso como agente anti-angiogénico
The equilibrium interaction of anti-cancer agent 1,3,6-naphatalene trisulfonate with human acidic fi broblast growthfactor has been studied by calorimetry. The affi nity decreases with increasing ionic strength. At pH 7.0 and 0.15 MNaCl concentration, a binding constant of the protein with the ligand was estimated in the 102 – 103 M-1 range, anaffi nity two orders of magnitude lower than that of aFGF with heparin. The interaction is enthalpically driven, andthe entropy change is unfavorable. A small heat capacity change with an unusual positive value of 90 cal K-1mol-1 wasdetermined from the temperature dependence of the enthalpies. Changes in accessible apolar and polar surface areasin the interaction were calculated from the thermodynamic data obtained and parametric equations in the literature.The results were compared with those measured from NMR data. The study includes structural bioenergetic considerationsabout the possible use of 1,3,6-naphatalene trisulfonate as an anti-angiogenic agent itself, or as a lead for thedevelopment of anti-angiogenic drugs.Se ha estudiado, mediante calorimetría isotérmica de reacción, la interacción del agente anticancerígeno 1,3,6-naftaléntrisulfonato con el factor de crecimiento para fi broblastos ácido humano. La afi nidad decrece con el aumento de lafuerza iónica. A pH 7,0 y NaCl 0,15 M, la constante de unión de la proteína con el ligando se encuentra en el rango102 – 103 M-1, una afi nidad dos órdenes de magnitud menor que la del FGFa por heparina. El cambio de entalpíafavorece la interacción, siendo el cambio de entropía desfavorable. De la dependencia del cambio de entalpía con latemperatura se calculó un pequeño cambio en la capacidad calorífi ca del proceso, con un valor excepcionalmentepositivo de 90 cal K-1mol-1. A partir de los datos termodinámicos medidos y de ecuaciones paramétricas establecidasen la literatura, se calcularon cambios en la superfi cie accesible al disolvente, tanto polar como apolar, que acompañana la interacción. Los resultados se compararon con los medidos mediante resonancia magnética nuclear. Elestudio incluye consideraciones de bioenergética estructural sobre el posible uso de 1,3,6-naftalén trisulfonato comoagente antiangiogénico o como molécula líder para el desarrollo de fármacos anti-angiogénicos
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