Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

El 3 de septiembre del 2009 arribó a la región de Guaymas, Sonora, la tormenta tropical Jimena, que permaneció estacionaria durante 36 h continuas, arrojando 720 mm de precipitación rebasando el promedio anual estatal. A causa de la lluvia, se formaron arroyos temporales que ocuparon los cauces originales, provenientes de la sierra El Aguaje, atrayendo a la fauna nativa. Debido a lo atípico de la situación, se planteó el objetivo de buscar organismos no registrados con anterioridad en la región en la literatura científica. Con este fin se realizó un muestreo en el arroyo formado en el puente La Marina, en San Carlos, Sonora. Se recolectaron 2 ejemplares de Macrobrachium olfersii: una hembra ovígera y un macho. Los especímenes recolectados en este trabajo constituyen el primer registro de la especie en esta área de Sonora, además de ser el sitio más norteño en el Pacífico de que se tiene conocimiento.

The diversity of araneomorph spiders in an ecoturistic tropical forest remnant of approximately 40 ha is described. A 1-ha plot with homogeneous vegetation was established. Six sampling methods covered all microhabitats, except tree canopy. Four expeditions were conducted from August 2011 to June 2012. In a total of 485 samples, 4,118 adult specimens representing 205 morphospecies were collected. Nonparametric richness estimates varied between 229 and 295 species. All collected morphospecies and species were documented with 2,233 digital images available at www.unamfcaracnolab.com. These images are intended to expedite species identification and to allow comparisons of taxa not formally described. Morphospecies identifications included: 91 species, 12 as similar to a described species, 86 to genus and 16 to family. Differences between seasonality and species collected revealed that March and June were similar in composition and were better represented in both number of species and adult specimens than August and November, although the collecting effort was the same. The similarity ranged between 0.35 and 0.71 among seasons.

Data from 241 interviews collected in 2013 was analyzed to characterize populations of pigs (Mexican Hairless Pig  (MH), Cuino Pig (CU) and Crossbred Pig (UD)). Variables were body weight (BW), head length (HL), body length (BL), thoracic perimeter (CG), height at withers (HW), croup width (RW), number of nipples (TC), dense or sparse hair (HD), presence or absence of tusks (TU), short or long snout (ST), upright or floppy ears (ER), calm or restless temperament (TM), proportionality index (PI), body index (BI) and relative weight index (RWI). Analyses were carried out with GLM and GENMOD of SAS. Models included state and population. Population was significant (P<0.05) for BW, BL, CG, HW, RW, TU, TM, PI, BI and RWI. Coefficients of variation (VC) showed the minor and major values for BW (18.8 %) and CG (27.8 %). VC were 13.0, 14.6 and 45.8 % for PI, BI and RWI. Least squares means for MH, CU and UD were: 48.06±6.17a, 35.93±3.04b and 61.11±7.42a kg (BW); 77.81±3.65ab, 69.56±2.02ª and 88.52±4.93b  cm (BL); 80.55±3.98ab, 71.72±2.20a and 93.23±5.37b cm (CG); 56.88±2.45ab, 51.26±1.36a and 60.32±3.31b cm (HW); 57±4a, 71±19b and 62±34a % (HD); 68±31ab, 70±14a and 61±27b% (TU); 65±30a, 56±12b and 62±3a% (TM). The MH and UD populations were similar in morphometry and different from the CU population. The CU population showed lower weight, smaller size and calmer temperament. The characterization of these populations is important for designing strategies for their conservation and efficient use.Data from 241 interviews collected in 2013 was analyzed to characterize populations of pigs (Mexican Hairless Pig  (MH), Cuino Pig (CU) and Crossbred Pig (UD)). Variables were body weight (BW), head length (HL), body length (BL), thoracic perimeter (CG), height at withers (HW), croup width (RW), number of nipples (TC), dense or sparse hair (HD), presence or absence of tusks (TU), short or long snout (ST), upright or floppy ears (ER), calm or restless temperament (TM), proportionality index (PI), body index (BI) and relative weight index (RWI). Analyses were carried out with GLM and GENMOD of SAS. Models included state and population. Population was significant (P<0.05) for BW, BL, CG, HW, RW, TU, TM, PI, BI and RWI. Coefficients of variation (VC) showed the minor and major values for BW (18.8 %) and CG (27.8 %). VC were 13.0, 14.6 and 45.8 % for PI, BI and RWI. Least squares means for MH, CU and UD were: 48.06±6.17a, 35.93±3.04b and 61.11±7.42a kg (BW); 77.81±3.65ab, 69.56±2.02ª and 88.52±4.93b  cm (BL); 80.55±3.98ab, 71.72±2.20a and 93.23±5.37b cm (CG); 56.88±2.45ab, 51.26±1.36a and 60.32±3.31b cm (HW); 57±4a, 71±19b and 62±34a % (HD); 68±31ab, 70±14a and 61±27b% (TU); 65±30a, 56±12b and 62±3a% (TM). The MH and UD populations were similar in morphometry and different from the CU population. The CU population showed lower weight, smaller size and calmer temperament. The characterization of these populations is important for designing strategies for their conservation and efficient use.

En bovinos productores de leche la curva de lactancia (CL) se ha analizado con modelos no lineales (MNL), y recientemente se ha implementado la metodología de MNL mixtos. Los objetivos fueron: a) ajustar un MNL a la CL a 240 días; b) comparar MNL vs MNL mixtos; c) estimar producción al pico (PMAX) y total a 240 días (PTOTAL), así como días para alcanzar la producción máxima (DPMAX). Se analizaron 15,324 observaciones de producción diaria (kg), correspondientes a primera lactancia de 2,809 vacas Siboney, con fecha de parto de 2000 a 2012 en 28 hatos. Se evaluaron cinco MNL: Wood, Wiltmink, Cobby, Brody y Sikka. Se realizaron dos análisis con el procedimiento NLMIXED de SAS: ANA1, incluyó sólo el efecto aleatorio de los residuales; y ANA2, incluyó el efecto aleatorio correspondiente a un coeficiente de regresión, más los residuales. La selección del modelo con mejor ajuste se realizó con: error de predicción promedio; varianza del error de predicción; estadístico Durbin Watson; coeficiente de determinación (R2); criterios de información Akaike (AIC) y Bayesiano (BIC). Los MNL mixtos mostraron el mejor ajuste con base en: a) los R2 del ANA2 fueron superiores, en un intervalo de 9 a 12 %; b) por la reducción en la varianza residual en el ANA2; y, c) los criterios AIC y BIC, mostraron mejor ajuste en los MNL del ANA2. El modelo de mejor ajuste en todo el estudio fue WOD del ANA2, con estimaciones para PMAX, DPMAX y PTOTAL de 7.71 kg, 40 días y 1,653 kg, respectivamente.

Los objetivos fueron caracterizar los perfiles de LH y testosterona (T) y la respuesta a GnRH en corderos de pelo. Estudio 1: se utilizaron corderos Blackbelly (n=4), Pelibuey (n=5), Blackbelly x Pelibuey (Cruzas; n=8). A las 2, 4, 8, 12, 16, 20 y 24 semanas de edad, se obtuvieron muestras de sangre cada 15 min durante 6 h, para caracterizar los perfiles de LH y T. No hubo diferencia entre genotipos a ninguna edad, para ninguna variable de LH y T (P>0.05); el efecto de la edad fue significativo (P<0.05): la concentración promedio de LH fue menor en la semana 2 (P<0.05), alcanzó el valor más alto en la 12, y disminuyó en la 16 (P<0.05). La concentración promedio de T aumentó constantemente entre 2 y 24 semanas (P<0.05). Estudio 2: se utilizaron corderos Blackbelly (n=4), Pelibuey (n=4), Cruzas (n=4). A las mismas edades, los corderos se desafiaron con GnRH (3, 9, 27 ng•kg-1 peso) y se obtuvieron muestras de sangre entre -15 y 180 min. En las semanas 8 y 12, la respuesta de LH fue mayor en los corderos Pelibuey, en comparación con Blackbelly. La respuesta de T tendió a ser diferente entre genotipos (P<0.10), con Blackbelly mostrando la menor respuesta. En conclusión, el desarrollo de los perfiles de LH y T no fue diferente entre genotipos, pero los corderos Pelibuey presentaron mayor capacidad de respuesta a GnRH en las semanas 8 y 12; es necesario determinar si estas diferencias tienen implicaciones sobre la capacidad reproductiva de los animales adultos.

When resources are scarce, mycobacteria stop growing to make way for genes adaptation allow. Conversely, whengrowth continues under stress conditions, specific genes metabolic networks for protection are activating. In thissense, the protein encoded by esat-6 (early secretory antigenic target, 6 kDa) gene in Mycobacterium tuberculosis,acting in the lysis of alveolar epithelial and macrophage membranes to escape and invade other cells. But it can have other functions, such as interfering with cell-cell contact and transfer their DNA. In M. smegmatis, the ESX-1 (Secretion Ejectosoma BOX) system that facilitates secretion of ESAT-6 protein, probably it is sensitive to one or more nutrients of the culture medium. So it in the present study culture conditions limiting nutrient for growth of M. smegmatis are evaluated and relate the expression of esat-6. Culture media tested were minimal medium Hartmans Bond (HdB), carbon-limited (HdB<C), nitrogen (HdB<N) and inorganic phosphate (HdB<Pi). M. smegmatis HdB adapted to minimal medium, HdB<C and HdB<N and resume its metabolic activity in fresh medium, but not expressed esat-6. In HdB <Pi M. smegmatis loses its metabolic capacity for resistance acid-alcohol and expressed esat-6. Therefore, the culture media tested as a model for gene expression under nutrient limitation is proposed.

This paper explores the history and outcomes of the digital convergence of public television in Latin America from the theoretical and methodological approach of the Political Economy of Communication. We analyze how the logic of industrialization and maximum gain that characterizes the current capitalist system has gained momentum since digitalization and hos, in this increasing rent-seeking context, public television has been reduced chances of broadcasting on new platforms. First, we delve into the features of Latin-American public television to identify differences among all the systems in the region. We then proceed to analyze the digital processes that have signed the industry in recent years. Finally, this research points out legal aspects that line the television in our continent. As any other industry, television merchandises contents that are linked with the Latin American media culture; that is why this research is valuable and important. As much we study television and its accidents, as much we understand cultural features affecting our society. Finally, digital convergence compels a twist in public television systems in order to survive, face changes in State policy, technological advances and alterations related with culture, tastes and targets.

This article considers the use of evidence coming from a variety of sources to substantiate bills introduced before the Chamber of Deputies. The Legislative, as a highly politicized arena, can rely on monitoring, evaluation and auditing tools not only for drafting initiatives, but also to inform and enrich the debate in a context where different ideologies converge systematically. This work suggests that the use of evidence is still an underutilized resource in Mexican legislative work. The main sources of information used in bills submitted to the Commission for Social Development at the Chamber of Deputies during the 60th, 61st and 62nd Legislatures are evaluated based on a case study. The most significant finding reveals that although evidences have been increasingly used in the legislative work, there is still significant potential for exploiting evidences from sources of a different nature, particularly those produced by agencies linked to the Chamber of Deputies, including the Superior Audit Office and the legislative studies centers.

The Arizona Congress issued in 2010 one of the toughest acts concerning undocumented immigration -the Arizona SB 1070. Some experts argue that subnational agencies should not pass immigration related policies in view of the potential negative impact of retaliation by third countries on both the diplomatic and economic relationships between the US and those countries and on their own economy. Conversely, Spiro (1994; 2001) stresses that nowadays States can identify whether a measure has been taken by a subnational agency in particular, and they can thus implement a focused reaction rather than targeting the whole country. The purpose of this work is to establish to what extent the current status of Mexico-US relationship is represented by either one of those perspectives. Also, this particular discussion is placed within the broader issue concerning whether the US states could and/or should play a more active role on immigration management. Bearing these goals in mind, we explore Mexico’s reactions to the SB1070 passage as well as the impact of the Arizona Act on US-Mexican relations.

The article aims at examining and questioning the notion of "clientelism" in its instrumental sense, based on an empirical study of the activities of political mediators in a northern Argentinian province. The daily doings of local leaders in various elective positions is studied with a qualitative methodological approach. The work reveals that the role of mediators involves not only individuals and particular groups, but also social and territorial groups who are the target of the distribution of public goods yielding collective gains. It is argued that the choice of the beneficiaries of the goods is hardly ever consistent with a simple cost-benefit assessment entailed by the instrumental notion of clientelism, as it rather implies rebuilding and solving the specific problems of the electoral basis’ members. The method of allocating resources is filtered by the mediator, who assigns them according to her/his knowledge of the represented territory and general policy orientations. The dualism between clientelistic and programmatic links is thus questioned, showing that the distribution of public goods by political mediators is always guided by symbolic and/or programmatic criteria. Thus, the author suggests a re-conceptualization of the notion of clientelism that accounts for the political representation dimension involved in this notion.