Reseña de "Cómo articular un proyecto de turismo rural sustentable y el acceso al agua sana", de Mónica Jiménez

Se aborda la experiencia particular de una hostería rural sustentable situada en territorio en conflictos, principalmente por el agua. Se desarrollan las estrategias para abordar las principales problemáticas de quienes habitan esa región salteña, interiorizandonos en las acciones de la asamblea. A lo largo de la exposición oral, ahora presentada en formato de texto, se van articulando las acciones llevadas adelante desde la hostería (y por la expositora en representación de la hostería), fundadas en pilares tales como el turismo sustentable, sostenible y responsable, la economía circular y el Buen Vivir; conceptos asumidos como compromisos e imbricados por un estar situado, donde lejos de optar por un estar pasivo•permisivo, se enfatiza la relevancia de lo colectivo en los procesos de lucha (en lo concreto: lucha por el agua sana) y se nutre a la misma con la participación y las acciones de forma organizada.Facultad de Ciencias Económica

An energy-based model approach to rare event probability estimation

The estimation of rare event probabilities plays a pivotal role in diverse fields. Our aim is to determine the probability of a hazard or system failure occurring when a quantity of interest exceeds a critical value. In our approach, the distribution of the quantity of interest is represented by an energy density, characterized by a free energy function. To efficiently estimate the free energy, a bias potential is introduced. Using concepts from energy-based models (EBM), this bias potential is optimized such that the corresponding probability density function approximates a pre-defined distribution targeting the failure region of interest. Given the optimal bias potential, the free energy function and the rare event probability of interest can be determined. The approach is applicable not just in traditional rare event settings where the variable upon which the quantity of interest relies has a known distribution, but also in inversion settings where the variable follows a posterior distribution. By combining the EBM approach with a Stein discrepancy-based stopping criterion, we aim for a balanced accuracy-efficiency trade-off. Furthermore, we explore both parametric and non-parametric approaches for the bias potential, with the latter eliminating the need for choosing a particular parameterization, but depending strongly on the accuracy of the kernel density estimate used in the optimization process. Through three illustrative test cases encompassing both traditional and inversion settings, we show that the proposed EBM approach, when properly configured, (i) allows stable and efficient estimation of rare event probabilities and (ii) compares favorably against subset sampling approaches

The Impact of Personal and Service-Related Factors on the Perceived Academic Success Among College Students

In recent years, student completion of the first year and second-year college curriculum has become a significant barrier to student success and retention especially at Historically Black Colleges and Universities. Despite low pass and retention rates, many degree programs in the U.S. require at least one college-level mathematics course, and the failure in this math course has contributed disproportionately to the failure to complete the first- and second-year curriculum. The purpose of this study was to examine the predictability of the relationship between selected personal, academic, and service-related factors and the perceived academic success in mathematics among college students. Specifically, this study was concerned with the predictive power of the variables gender, ethnicity, course schedules, degree program, type of instructional method, tutoring, advisement, and faculty mentoring on the perceived academic success in math among college students. The present study provides pertinent data on the significant association between personal characteristics of college students and their academic performance in mathematics. By being able to identify the personal characteristics of these college students who are not successful in math courses, the institution will be able to develop programs to assist them in enhancing their academic performance in mathematics. Also, this study enhances college administrators’ level of awareness of how student support service factors influence the academic achievement of college students in mathematics related courses. By understanding how these factors are related administrators on college campuses can develop insight into the type of service support college students will need to navigate mathematics courses, particularly at the freshman and sophomore levels

Information provided by Spanish university websites on their assessment and quality processes

We analyze and evaluate the information provided by Spanish public universities on the web about their assessment and quality processes with the aim of detecting aspects for improvement and identifying best practices in universities that could act as a benchmark for the rest of the sector. A ested model/template incorporating a set of criteria and indicators is used to determine the quality of this information. The strengths and weaknesses of institutional websites are analyzed at both individual level and as a whole; the possible relation between website quality and the characteristics of the universities is also examined

Inference of geostatistical hyperparameters with the correlated pseudo-marginal method

We consider non-linear Bayesian inversion problems targeting the geostatistical hyperparameters of a random field describing hydrogeological or geophysical properties given hydrogeological or geophysical data. This problem is of particular importance in the non-ergodic setting as there are no analytical upscaling relationships linking the data to the hyperparameters, such as, mean, standard deviation, and integral scales. Full inversion of the hyperparameters and the local properties of the field (typically involving many thousands of unknowns) brings substantial computational challenges, such that simplifying model assumptions (e.g., homogeneity or ergodicity) are typically made. To prevent the errors resulting from such simplified assumptions while also circumventing the burden of high-dimensional full inversions, we use a pseudo-marginal Metropolis–Hastings algorithm that treats the random field as latent variables. In this random effects model, the intractable likelihood of observing the data given the hyperparameters is estimated by Monte Carlo averaging over realizations of the random field. To increase the efficiency of the method, low-variance approximations of the likelihood ratio are obtained by using importance sampling and by correlating the samples used in the proposed and current steps of the Markov chain. We assess the performance of this correlated pseudo-marginal method by considering two representative inversion problems involving diffusion-based and wave-based physics, respectively, in which we infer the hyperparameters of (1) hydraulic conductivity fields using apparent hydraulic conductivity data in a data-poor setting and (2) fracture aperture fields using borehole ground-penetrating radar (GPR) reflection data in a more data-rich setting. For the first test case, we find that the correlated pseudo-marginal method generates similar estimates of the geostatistical mean as classical rejection sampling, while an inversion assuming ergodicity provides biased estimates. For the second test case, we find that the correlated pseudo-marginal method estimates the hyperparameters well, while rejection sampling is computationally unfeasible and a simplified model assuming homogeneity leads to biased estimates

Information provided by Spanish university websites on their assessment and quality processes

25 p.We analyze and evaluate the information provided by Spanish public universities on the web about their assessment and quality processes with the aim of detecting aspects for improvement and identifying best practices in universities that could act as a benchmark for the rest of the sector. A tested model/template incorporating a set of criteria and indicators is used to determine the quality of this information. The strengths and weaknesses of institutional websites are analyzed at both individual level and as a whole; the possible relation between website quality and the characteristics of the universities is also examined.S

Improved Delta Sigma Modulators for High Speed Applications

International audienceThis article presents a new Low-Pass Delta Sigma Modulators (LPDS) architecture to improve the noise shaping for high frequency applications. The errors resulting from approximations made by calculating with 1/2N coefficients are compensated. Simulations with extracted parasitics of the layout are made and give a SNDR of 111 dB, 3.8 mW power consumption at 4 GHz in 65 nm CMOS technology for UMTS standard

St. John\u27s Wort inhibits adipocyte differentiation and induces insulin resistance in adipocytes

Adipocytes are insulin sensitive cells that play a major role in energy homeostasis. Obesity is the primary disease of fat cells and a major risk factor for the development of Type II diabetes, cardiovascular disease, and metabolic syndrome. Obesity and its related disorders result in dysregulation of the mechanisms that control adipocyte gene expression and function. To identify potential novel therapeutic modulators of adipocytes, we screened 425 botanical extracts for their ability to modulate adipogenesis and insulin sensitivity. We observed that less than 2% of the extracts had substantial effects on adipocyte differentiation of 3T3-L1 cells. Two of the botanical extracts that inhibited adipogenesis were extracts from St. John\u27s Wort (SJW). Our studies revealed that leaf and flower, but not root, extracts isolated from SJW inhibited adipogenesis as judged by examining PPARγ and adiponectin levels. We also examined the effects of these SJW extracts on insulin sensitivity in mature 3T3-L1 adipocytes. Both leaf and flower extracts isolated from SJW substantially inhibited insulin sensitive glucose uptake. The specificity of the observed effects was demonstrated by showing that treatment with SJW flower extract resulted in a time and dose dependent inhibition of insulin stimulated glucose uptake. SJW is commonly used in the treatment of depression. However, our studies have revealed that SJW may have a negative impact on adipocyte related diseases by limiting differentiation of preadipocytes and significantly inducing insulin resistance in mature fat cells. © 2009 Elsevier Inc. All rights reserved

Intelligent chilled mirror humidity sensor

A new, intelligent, chilled mirror humidity instrument has been designed for use on buoys and ships. The design goal is to make high quality dew point temperature measurements for a period of up to one year from an unattended platform, while consuming as little power as possible. Nominal system accuracy is 0.3°C, and a measure of data quality is provided to indicate possible drift in calibration. Energy consumption is typically 800 Joules per measurement; standby power consumption is 0.05 watts. Control of the instrument is managed by an onboard central processing unit which is programmable in BASIC, and communication to an external data logger is provided through an RS232 compatible interface. This report describes the preliminary sensor tests that led to this new design and provides the complete technical description required for fabrication.Funding was provided by the Office of Naval Research under contract Number N00014-84-C-0134, and the National Science Foundation through grant Number OCE87- 09614