¿Cómo monitorear el movimiento del ganado en un mosaico de áreas boscosas con GPS en combinación con SIG?

El manejo de bosques de Piñon-Juniper (PJ) ocupa más de 30 millones de hectáreas en el oeste de Estados Unidos. Este ecosistema constituye un importante recurso para la producción y conservación de vida silvestre. Sin embargo, estos han cambiado considerablemente los últimos 30 años, principalmente para manejar ganado en pastoreo. El objetivo fue determinar la cobertura de dosel (TCC) y monitorear, durante la primavera, el uso del ganado del paisaje arbolado. El estudio se realizó en una pastura de 146 ha de la zona central de Nuevo México. La TCC de PJ se determinó a partir de ortofotos digitales recientes usando Feature Analyst® para ArcGIS® 9.1. El sitio de estudio fue segmentado en celdas de 1 ha para mapear cobertura arbórea. Ocho vacas, equipadas con GPS, fueron rastreadas durante 31 días a intervalos de 5 min. Una sección de la pastura con cobertura arbórea mayor que 30 % se utilizó para describir la relación distribución de pastoreo y cobertura de dosel. Se encontró una relación exponencial negativa significativa entre TCC y el uso relativo del ganado (y = 450,41e-12,329x). La cubierta arbórea explicó 50,1 % de la variación en la utilización relativa por el ganado de las celdas. La mayoría de las posiciones animales registradas en áreas dominadas por PJ ocurrieron en celdas con 30-50 % de TCC. Una cobertura del dosel de 50 % podría proporcionar un equilibrio adecuado entre la permanencia y el consumo de  forraje para el ganado durante la primavera

Estimation of Groundwater Recharge at Pahute Mesa using the Chloride Mass-Balance Method

Groundwater recharge on Pahute Mesa was estimated using the chloride mass-balance (CMB) method. This method relies on the conservative properties of chloride to trace its movement from the atmosphere as dry- and wet-deposition through the soil zone and ultimately to the saturated zone. Typically, the CMB method assumes no mixing of groundwater with different chloride concentrations; however, because groundwater is thought to flow into Pahute Mesa from valleys north of Pahute Mesa, groundwater flow rates (i.e., underflow) and chloride concentrations from Kawich Valley and Gold Flat were carefully considered. Precipitation was measured with bulk and tipping-bucket precipitation gauges installed for this study at six sites on Pahute Mesa. These data, along with historical precipitation amounts from gauges on Pahute Mesa and estimates from the PRISM model, were evaluated to estimate mean annual precipitation. Chloride deposition from the atmosphere was estimated by analyzing quarterly samples of wet- and dry-deposition for chloride in the bulk gauges and evaluating chloride wet-deposition amounts measured at other locations by the National Atmospheric Deposition Program. Mean chloride concentrations in groundwater were estimated using data from the UGTA Geochemistry Database, data from other reports, and data from samples collected from emplacement boreholes for this study. Calculations were conducted assuming both no underflow and underflow from Kawich Valley and Gold Flat. Model results estimate recharge to be 30 mm/yr with a standard deviation of 18 mm/yr on Pahute Mesa, for elevations >1800 m amsl. These estimates assume Pahute Mesa recharge mixes completely with underflow from Kawich Valley and Gold Flat. The model assumes that precipitation, chloride concentration in bulk deposition, underflow and its chloride concentration, have been constant over the length of time of recharge

Adolescent health: A rural community's approach

Open accessIntroduction: Significant health problems encountered in adulthood often have their roots in health behaviours initiated during adolescence. In order to reverse this trend, school and health personnel, as well as parents and other community members working with high school students, need to be aware of the health-related beliefs and choices that guide the behaviours of teenagers. Although a wide variety of research has been conducted on this topic among urban adolescents, less is known about the health beliefs and behaviors of adolescents residing in rural areas, particularly in Canada. In general, rural Canadians are less healthy than their urban counterparts. Building on the knowledge and understanding of their own community, key stakeholders were invited to engage in the design and implementation of a participatory action research project aimed at understanding and improving the health of rural adolescents. Methods: A group of parents, teachers, students, school administrators and public health nurses engaged in a participatory action research project to better understand determinants of the health of rural adolescents at a high school in Western Canada. Group members developed and administered a health survey to 288 students from a small rural high school, in an effort to identify areas of concern and interest regarding health practices and beliefs of rural adolescents, and to take action on these identified concerns. Results: Results indicated some interesting but potentially worrying trends in this population. For example, while frequent involvement in a physical activity was noted by 75.9% of participants, close to half of the females (48%) described their body image as ‘a little overweight’ or ‘definitely overweight’, and approximately 25.8% of respondents noted that they skipped meals most of the time. Differences between the genders were apparent in several categories. For example, more girls smoked (16.2%) than boys (12.3%), and more males (55.0%) than females (41%) had tried illegal drugs. Participants indicated awareness of other health-compromising behaviours, including unsafe driving habits and high stress levels, and acknowledged several steps they wanted to take to improve their health, as well as the barriers to taking those steps. Students identified improved nutrition, stress reduction, and increased levels of physical activity as particular important health goals. Students also recommended ways in which information and support could be provided within the school environment to enable them to achieve their health-related goals. Several activities developed in collaboration with students have incorporated the recommendations, and have spawned other activities in response to the ongoing identification of new concerns. Conclusions: The process of including the rural community in the identification of health assets and needs from the perspective of students - as well as the planning and implementation of appropriate strategies to address those needs - demonstrates the strengths inherent within a small rural population. Community members’ awareness of the need to create a healthy environment for youth is reflected in their willingness to participate in activities leading to improved health. Greater awareness of the health needs of rural adolescents, and of the influence of gender in some aspects of health behaviors, will help researchers to explore ways in which the unique culture of rural communities can be harnessed to help shape health-focused interventions.Ye

Adolescent health: A rural community's approach

First published in Rural and Remote Health [http://www.rrh.org.au]. Authors of articles published in Rural and Remote Health retain copyright.Introduction: Significant health problems encountered in adulthood often have their roots in health behaviours initiated during adolescence. In order to reverse this trend, school and health personnel, as well as parents and other community members working with high school students, need to be aware of the health-related beliefs and choices that guide the behaviours of teenagers. Although a wide variety of research has been conducted on this topic among urban adolescents, less is known about the health beliefs and behaviors of adolescents residing in rural areas, particularly in Canada. In general, rural Canadians are less healthy than their urban counterparts. Building on the knowledge and understanding of their own community, key stakeholders were invited to engage in the design and implementation of a participatory action research project aimed at understanding and improving the health of rural adolescents. Methods: A group of parents, teachers, students, school administrators and public health nurses engaged in a participatory action research project to better understand determinants of the health of rural adolescents at a high school in Western Canada. Group members developed and administered a health survey to 288 students from a small rural high school, in an effort to identify areas of concern and interest regarding health practices and beliefs of rural adolescents, and to take action on these identified concerns. Results: Results indicated some interesting but potentially worrying trends in this population. For example, while frequent involvement in a physical activity was noted by 75.9% of participants, close to half of the females (48%) described their body image as ‘a little overweight’ or ‘definitely overweight’, and approximately 25.8% of respondents noted that they skipped meals most of the time. Differences between the genders were apparent in several categories. For example, more girls smoked (16.2%) than boys (12.3%), and more males (55.0%) than females (41%) had tried illegal drugs. Participants indicated awareness of other health-compromising behaviours, including unsafe driving habits and high stress levels, and acknowledged several steps they wanted to take to improve their health, as well as the barriers to taking those steps. Students identified improved nutrition, stress reduction, and increased levels of physical activity as particular important health goals. Students also recommended ways in which information and support could be provided within the school environment to enable them to achieve their health-related goals. Several activities developed in collaboration with students have incorporated the recommendations, and have spawned other activities in response to the ongoing identification of new concerns. Conclusions: The process of including the rural community in the identification of health assets and needs from the perspective of students - as well as the planning and implementation of appropriate strategies to address those needs - demonstrates the strengths inherent within a small rural population. Community members’ awareness of the need to create a healthy environment for youth is reflected in their willingness to participate in activities leading to improved health. Greater awareness of the health needs of rural adolescents, and of the influence of gender in some aspects of health behaviors, will help researchers to explore ways in which the unique culture of rural communities can be harnessed to help shape health-focused interventions.Ye

The Effect of Volitional Preemptive Abdominal Contraction on Biomechanical Measures During A Front Versus Back Loaded Barbell Squat

# Background Weightlifting is growing in popularity among recreational and competitive athletes. The barbell back squat (BackS) is commonly included in these training programs, while the barbell front squat (FrontS) is commonly performed as a component of other lifts such as the power clean or clean and jerk, it is less commonly practiced in isolation. # Hypothesis/Purpose The purpose of this study was to examine the effects of VPAC performance on trunk muscle and LE biomechanical responses during loaded BackS versus FrontS in healthy subjects. # Study Design Controlled Laboratory Study # Methods Healthy male subjects with the ability to perform a sub-maximal loaded barbell squat lift were recruited. Subjects completed informed consent, demographic/medical history questionnaires and an instructional video. Subjects practiced VPAC and received feedback. Surface electromyography (sEMG) electrodes and kinematic markers were applied. Muscles included were the internal oblique (IO), external oblique (EO), rectus abdominis, iliocostalis lumborum (ICL), superficial multifidi, rectus femoris, vastus lateralis, biceps femoris, and gluteus maximus. Maximal voluntary isometric contractions established reference sEMG values. A squat one-rep-max (1RM) was predicted by researchers using a three to five repetition maximum (3RM, 5RM) load protocol. Subjects performed BackS trials at 75% 1RM while FrontS trials were performed at 75% BackS weight, both with and without VPAC. Subjects performed three repetitions of each condition with feet positioned on two adjacent force plates. Significant interactions and main effects were tested using a 2(VPAC strategy) x 2(squat variation) and 2(VPAC strategy) x 2(direction) within-subject repeated measures ANOVAs. Tukey's Post-Hoc tests identified the location of significant differences. # Results Trunk muscle activity was significantly higher during FrontS versus BackS regardless of VPAC condition. (IO: p=0.018, EO: p\<0.001, ICL: p\<0.001) VPAC increased performance time for both squat variations (p=.0011), which may be associated with decreased detrimental force potential on the lumbar spine and knees. VPAC led to improved ability to maintain a neutral lumbar spine during both squat variations. This finding is associated with decreased detrimental force potential on the lumbar spine. # Conclusions Findings could help guide practitioners and coaches to choose squat variations and incorporate VPAC strategies during their treatments and/or training programs. # Level of Evidence Level 3 ©The Author(s

SCD1 Inhibition Causes Cancer Cell Death by Depleting Mono-Unsaturated Fatty Acids

Increased metabolism is a requirement for tumor cell proliferation. To understand the dependence of tumor cells on fatty acid metabolism, we evaluated various nodes of the fatty acid synthesis pathway. Using RNAi we have demonstrated that depletion of fatty-acid synthesis pathway enzymes SCD1, FASN, or ACC1 in HCT116 colon cancer cells results in cytotoxicity that is reversible by addition of exogenous fatty acids. This conditional phenotype is most pronounced when SCD1 is depleted. We used this fatty-acid rescue strategy to characterize several small-molecule inhibitors of fatty acid synthesis, including identification of TOFA as a potent SCD1 inhibitor, representing a previously undescribed activity for this compound. Reference FASN and ACC inhibitors show cytotoxicity that is less pronounced than that of TOFA, and fatty-acid rescue profiles consistent with their proposed enzyme targets. Two reference SCD1 inhibitors show low-nanomolar cytotoxicity that is offset by at least two orders of magnitude by exogenous oleate. One of these inhibitors slows growth of HCT116 xenograft tumors. Our data outline an effective strategy for interrogation of on-mechanism potency and pathway-node-specificity of fatty acid synthesis inhibitors, establish an unambiguous link between fatty acid synthesis and cancer cell survival, and point toward SCD1 as a key target in this pathway

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

MONAI: An open-source framework for deep learning in healthcare

Artificial Intelligence (AI) is having a tremendous impact across most areas of science. Applications of AI in healthcare have the potential to improve our ability to detect, diagnose, prognose, and intervene on human disease. For AI models to be used clinically, they need to be made safe, reproducible and robust, and the underlying software framework must be aware of the particularities (e.g. geometry, physiology, physics) of medical data being processed. This work introduces MONAI, a freely available, community-supported, and consortium-led PyTorch-based framework for deep learning in healthcare. MONAI extends PyTorch to support medical data, with a particular focus on imaging, and provide purpose-specific AI model architectures, transformations and utilities that streamline the development and deployment of medical AI models. MONAI follows best practices for software-development, providing an easy-to-use, robust, well-documented, and well-tested software framework. MONAI preserves the simple, additive, and compositional approach of its underlying PyTorch libraries. MONAI is being used by and receiving contributions from research, clinical and industrial teams from around the world, who are pursuing applications spanning nearly every aspect of healthcare.Comment: www.monai.i