Mexican migration to the United States : the view from rural sending communities

"June 1976.""#2118"--handwritten on coverIncludes bibliographical reference

Large-scale Nonlinear Variable Selection via Kernel Random Features

We propose a new method for input variable selection in nonlinear regression. The method is embedded into a kernel regression machine that can model general nonlinear functions, not being a priori limited to additive models. This is the first kernel-based variable selection method applicable to large datasets. It sidesteps the typical poor scaling properties of kernel methods by mapping the inputs into a relatively low-dimensional space of random features. The algorithm discovers the variables relevant for the regression task together with learning the prediction model through learning the appropriate nonlinear random feature maps. We demonstrate the outstanding performance of our method on a set of large-scale synthetic and real datasets.Comment: Final version for proceedings of ECML/PKDD 201

How the high-income class uses a public space: The neighbourhood square in Goiánia/Brazil

The public space has an important role in fostering urban life, since it absorbs and mediatesconflicts between public and private dimensions (CALDEIRA, 2007; VAZ, 2010; OLIVEIRA, 2013). Its appropriation and maintenance in Brazil havebeen considered ineffective, discontinued or privileged; the special differentiation and pressure is run by the higher income classes, which have territory control (LOJKINE, 1981; CASTELLS, 1983; VILLAÇA, 2001). This elite is composed by landowners who command the production process and is politically and ideologically dominant (OLIVEIRA, 1975). Its residencecommonly occurs: (I) in the central areas in vertical condominiums (with easy accessibility to commerce, retail, and other services); and (II) horizontal condominiumsin the urban fringes (because of safety, distinction, and availability of space). Basedon these premises, this study aims at understanding in which way the higher income classes take possession of public spaces in the context of “neighbourhood squares”. With a descriptive and exploratory approach, it considers as a case study T-23 square inGoiânia, an expensive regionthat ownsa complete infrastructure. The analysis is structured in two parts: (1) identification of existing elements, activities, and ways of occupation; and (2), through interviews, recordsof motivating criteria of use and residential rental. The results point to a consistent appropriation, by users of different ages and profiles, in distinct activities in different periods; they reveal use and socialization of the residents. Vitality promoting elements, associated with the proximity of quality equipment and its good conservation, seems to justify the occupation and appropriatio

Thermal energy production by a dual solar pound

A Salt Gradient Solar Pond (SGSP) is a salt water basin that collects and stores solar energy. These devices rely on the existence of a non-convective zone (NCZ) that functions as a transparent thermal insulation zone, created by a salt gradient. Salinity and temperature gradients in this zone can give rise to double diffusive problems that can decrease the insulation properties of this zone. The stability of this zone is thus crucial in a SGSP. Stability control, analysis of energy extraction, device efficiency and maintenance strategies are determinant for the correct performance of the SGSP. The implementation of these strategies can be expensive and not sufficient to prevent instability problems. This paper intends to give a contribution to the maintenance problem presenting a new concept of a SGSP utilisation: The Dual Solar Pond (DSP

Short-Cut Methods for Multicomponent Batch Distillation

This work present the batch distillation shortcut methods developed from the Fenske-Underwood-Gilliland (FUG) method of continuous distillation. In addition, a comparison between the results of shortcut method developed by Diwekar and Narváez-García et al. is done. The results of both methods are compared for validation with the results using the rigorous method presented by Domenech and Enjalbert. The results indicate no significant differences in both shortcut methods being the maximum deviation found between the two shortcut methods is less than 3%. Then, the use of any of both methods is in the ease or difficulty of the solution each of the model equations. Both methods were implemented using Fortran programming. Multdistbatch© software was used for the rigorous method

Baseline pathological data of the wedge clam Donax trunculus from the Tyrrhenian Sea (Mediterranean Basin)

In recent years, a collapse in Donax trunculus fishing yields has occurred in the Tyrrhenian Sea (Mediterranean Basin). There is little information available on the impact disease may have had on D. trunculus populations. For the first time, a pathological survey was performed on the natural beds of the bivalve on the Campania and Lazio coasts, western Italy. Detected pathogens and related diseases were analysed, and their prevalence and mean intensity values were calculated. Viral particles, Chlamydia-like organisms, ciliates, coccidians, microcells and trematodes were observed. An unknown ciliate was linked to severe inflammatory and necrotic lesions in the digestive gland. Metacercariae of the trematode Postmonorchis sp. were also strongly represented in almost all samples, reaching high levels of infection; however, none of the pathogens described required the World Organisation for Animal Health to be notified. Initial results indicated that further surveys related to environmental data are necessary in order to assess the relevance of these early observations in managing the declining D. trunculus population in the Tyrrhenian Sea.postprin

Estudio del proceso de cambio conceptual y la construcción del modelo científico precursor de ser vivo en niños de pre-escolar

La presente investigación estudia el cambio conceptual y la construcción de modelos científicos precursores en un contexto socioconstructivista con niños pequeños, utilizando una metodología cualitativa. Se analizan los cambios epistemológicos y ontológicos en las concepciones de los niños acerca de los seres vivos y cómo una estrategia didáctica basada en la construcción de un modelo científico precursor basado en propiedades biológicas los promueven. Los cambios en la comprensión de los niños fueron significativos en las dimensiones ontológicas y epistemológicas, presentando diferentes patones. Los segundos proporcionaron una mejor coherencia explicativa en su sistema conceptual contribuyendo, de esta forma, a los cambios ontológicos y promoviendo, a su vez, la construcción del modelo científico precursor de ser vivo

Pathways from Food Insecurity to Health Outcomes among California University Students

The prevalence of food insecurity (FI) among college students is alarmingly high, yet the impact on student health has not been well investigated. The aim of the current study was to examine the simultaneous relationships between food insecurity and health-related outcomes including body mass index (BMI) and overall health in a college student population. Randomly sampled students in the University of California 10 campus system were invited to participate in an online survey in spring 2015. The analytic sample size was 8705 graduate and undergraduate students. Data were collected on FI in the past year, daily servings of fruits and vegetables (FV), number of days in the past week of enough sleep and moderate- to vigorous-intensity physical activity (MVPA), height and weight, self-rated health, and student characteristics. Using path analysis, mediated pathways between FI, BMI, and poor health were examined through FV intake, number of days of MVPA and enough sleep. Analyses controlled for student characteristics. Mean BMI was 23.6 kg/m2 (SD, 5.0), and average self-rated health was good. FI was directly and indirectly related to higher BMI and poor health through three pathways. First, FI was related to fewer days of enough sleep, which in turn was related to increased BMI and poor health. Second, FI was related to fewer days of MVPA, which in turn was related to increased BMI and poor health. Third, FI was related to fewer daily servings of FV, which in turn was related to poor health. FI is associated with poor health behaviors among college students, which may contribute to higher weight status and poor health. These findings highlight the importance of food security for a healthy college experience.University of California (UC) Office of the President's Global Food InitiativeOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Determining appropriate approaches for using data in feature selection

Feature selection is increasingly important in data analysis and machine learning in big data era. However, how to use the data in feature selection, i.e. using either ALL or PART of a dataset, has become a serious and tricky issue. Whilst the conventional practice of using all the data in feature selection may lead to selection bias, using part of the data may, on the other hand, lead to underestimating the relevant features under some conditions. This paper investigates these two strategies systematically in terms of reliability and effectiveness, and then determines their suitability for datasets with different characteristics. The reliability is measured by the Average Tanimoto Index and the Inter-method Average Tanimoto Index, and the effectiveness is measured by the mean generalisation accuracy of classification. The computational experiments are carried out on ten real-world benchmark datasets and fourteen synthetic datasets. The synthetic datasets are generated with a pre-set number of relevant features and varied numbers of irrelevant features and instances, and added with different levels of noise. The results indicate that the PART approach is more effective in reducing the bias when the size of a dataset is small but starts to lose its advantage as the dataset size increases

Los usuarios en la grieta: retomas de lo político en los sitios "Choripan & Vino" y "Peronismo Intergaláctico"

El trabajo que presentamos pretende ser un aporte descriptivo sobre los modos en los que se produce la lectura de lo político y su circulación en las redes sociales. Fue realizado en el marco del proyecto de investigación UBACyT “Absorciones y retomas discursivas. El campo de los efectos” (directora: María Rosa Del Coto; co-directora: Graciela Varela). Es importante destacar que la noción de medio es utilizada para denominar también a las redes sociales, partiendo de la definición que propone Eliseo Verón: “El término (…), designa para mí no solamente un dispositivo tecnológico particular (por ejemplo, la producción de imágenes y de sonidos sobre un soporte magnético) sino la conjunción de un soporte y de un sistema de prácticas de utilización (producción/reconocimiento)” (Verón: 2004: 144). Dentro del proyecto en el cual se enmarca esta investigación se entiende como retoma a los conceptos habilitados a partir de la década del ´70 alrededor de la definición intertextual de la vida discursiva (Bajtín, 1985; Kristeva, 1978; Angenot, 1996). "Todo enunciado es un eslabón en la cadena, muy complejamente organizada, de otros enunciados" Bajtín (1985).Eje 13. Análisis del discurso y estudios del lenguajeFacultad de Periodismo y Comunicación Socia