279 research outputs found

    Interactividad controlada entre élites políticas y ciudadanos: diálogos públicos en Facebook en las campañas electorales jaliscienses de 2018

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    La arquitectura de las redes sociodigitales fue diseñada, al menos en teoría, para el desarrollo de diálogos horizontales, transparentes, interactivos y democráticos. Por ello, no poco vaticinaron que estas nuevas plataformas revolucionarían distintos campos de la vida humana, entre ellos el de la comunicación entre élites políticas y ciudadanos. En este marco, esta investigación presentación una observación a los perfiles públicos de Facebook de los tres candidatos más importantes al gobierno de Jalisco en las elecciones de 2018. El objetivo central de esta observación fue analizar la forma en la que los candidatos se comunicaron con los usuarios de Facebook, y, en particular, cómo es que están propiciando, o no, diálogos públicos durante las campañas electorales. A partir de un análisis de texto cualitativo a las publicaciones de los candidatos, la investigación encontró que a) no existieron las condiciones estructurales y coyunturales para que todos los electores jaliscienses pudieran participar en los diálogos entre las élites políticas y los ciudadanos; b) que las campañas políticas no presentaron estrategias públicas y explícitas que incentivaran dichos diálogos; y que c) aún así, existieron interacciones entre políticos y usuarios de internet. Estas interacciones estuvieron concentradas en conversaciones ligeras y no en intercambios sustanciales sobre la vida pública del estado. El artículo concluye que las tres campañas utilizaron Facebook para establecer una “interacción controlada” son los usuarios de internet, un tipo de interacción que está lejos de las problemas que las tecnologías de la web 2.0 prometieron a las democracias contemporáneas.ITESO, A.C

    "Review: Application of Bioequivalence Testing of Medicines in Peru"

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    "This is a review of the current status of drug bioequivalence studies in Peru. A bibliographic search was conducted in PubMed (Medline database) for bioequivalence studies in Peru. Generic drugs constitute the basis of pharmacological requests in health care systems in Latin American countries. Peru has enacted laws and regulations that require bioequivalence studies of high health risk drugs and exemptions, based on international legislation, to be conducted in research centers accredited by the authority of Health. There is a list of 19 drugs that must demonstrate their therapeutic equivalence through in vivo or in vitro studies, of which 13 have shown bioequivalence in vivo, and 8 of those have shown bioequivalence in vitro. There is a challenge for health authorities to enforce the current legislation and an even greater challenge for pharmaceutical laboratories to demonstrate bioequivalence of multi-source drugs with the reference drug.

    "Bioadsorption of silver ions by calcareous chitin, chitin and chitosan"

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    "Context: Calcareous chitin, chitin, chitosan, and their modifications are used as bioadsorbents of metals and dyes that cause environmental pollution, endocrine disruption, and human diseases. Aims: To evaluate the selective bioadsorption of silver ions (Ag+ ) by calcareous chitin, chitin, and chitosan. Methods: Experimental and prospective study. The presence of functional groups of the bioadsorbents was identified by Fourier-transformed infrared spectroscopy (FT-IR), 1H-NMR spectroscopy and scanning electron microscopy (SEM). The Langmuir, Freundlich, and Elovich models were applied to describe the adsorption capacity of bioadsorbents according to granule size (20-40, 40-60, 60-80 meshes) and temperature (10, 20, and 30°C). Results: The FT-IR spectrum of calcareous chitin indicates the presence of carbonate (CO3 = 1420 cm-1 ), amide III (1313 cm-1 ), –OH groups (3441.90 cm-1 ), and pyranose structure (952.83 cm-1 ); chitin has –OH groups (3441.90 cm-1 ), NH (3268 cm-1 ), amide I (1654 cm-1 ) and II (1559 cm-1 ); chitosan has –OH groups (3419.90 cm-1 ), –NH (3200 cm-1 ), amide I (1712.18 cm-1 ), –NH2 (1654.46 cm-1 ), amide III (1317.11 cm-1 ) and pyranose structure (1070.12 cm-1 and 1031 cm-1 ). The Langmuir model indicates greater bioadsorption of Ag+ ions at smaller particle sizes (60-80 = 0.25-0.18 mm) and at a temperature of 20-30°C. Conclusions: The bioadsorption of silver ions (Ag+ ) by chitosan is greater with respect to calcareous chitin and chitin; the Langmuir model fits for the Ag+ isotherm and suggests that the process is controlled by physisorption.

    Nut production in Bertholletia excelsa across a logged forest mosaic: implications for multiple forest use

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    Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù

    Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

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    Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal

    A study of the dry forest communities in the Dominican Republic

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    This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani (thorny dry forest on coastal dunes), Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest), Consoleo moniliformis-Camerarietum linearifoliae (dry forest on hard limestones), Lemaireocereo hystricis-Prosopidetum juliflorae (northern Dominican disturbed dry forest), Lycio americani-Prosopidetum juliflorae (disturbed dry forest on saline soils) and Guettardo ellipticae-Guapiretum discoloris (dry forest on flat-topped hillocks in Montecristi). This is an important step forward in the phytosociological and floristic studies of the Caribbean territories.Este trabalho apresenta um estudo florístico e fitossociológico das comunidades de florestas secas da República Dominicana. Um total de 69 amostras foram obtidas pelo método relevé em biótopos florestais secos. As amostras foram posteriormente submetidas à análise de correspondência destendenciada para a determinação e estudo de possíveis agrupamentos. O estudo não abrange formações arbóreas desenvolvidas sobre serpentinitos, nem as chamadas florestas semideciduais, peculiares às áreas de maior pluviosidade. Foram identificados nove fitocenoses. Os resultados mais significativos levaram à descrição de seis novas associações fitossociológicas: Simaroubetum berteroani (floresta espinhosa seca em dunas costeiras), Phyllostylo rhamnoidis-Prosopidetum juliflorae (floresta seca perturbada do sul da República Dominicana), Consoleo moniliformis-Camerarietum linearifoliae (floresta seca sobre calcários compactos), Lemaireocereo hystricis-Prosopidetum juliflorae (floresta seca perturbada do norte da República Dominicana), Lycio americani-Prosopidetum juliflorae (floresta seca perturbada desenvolvida em solos salinos) Guettardo ellipticae-Guapiretum discoloris (floresta seca em colinas de topo achatado em Montecristi). O trabalho realizado representa um importante avanço nos estudos fitossociológicos e florísticos dos territórios do Caribe.This research paper was possible thanks to the sponsorship of the Agencia Española de Cooperación Internacional para el Desarrollo (AECID), under the auspices of the Ministerio de Asuntos Exteriores y de Cooperación de España, which funded the project (cod. A/3499/05)

    A complete set of nascent transcription rates for yeast genes

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    The amount of mRNA in a cell is the result of two opposite reactions: transcription and mRNA degradation. These reactions are governed by kinetics laws, and the most regulated step for many genes is the transcription rate. The transcription rate, which is assumed to be exercised mainly at the RNA polymerase recruitment level, can be calculated using the RNA polymerase densities determined either by run-on or immunoprecipitation using specific antibodies. The yeast Saccharomyces cerevisiae is the ideal model organism to generate a complete set of nascent transcription rates that will prove useful for many gene regulation studies. By combining genomic data from both the GRO (Genomic Run-on) and the RNA pol ChIP-on-chip methods we generated a new, more accurate nascent transcription rate dataset. By comparing this dataset with the indirect ones obtained from the mRNA stabilities and mRNA amount datasets, we are able to obtain biological information about posttranscriptional regulation processes and a genomic snapshot of the location of the active transcriptional machinery. We have obtained nascent transcription rates for 4,670 yeast genes. The median RNA polymerase II density in the genes is 0.078 molecules/kb, which corresponds to an average of 0.096 molecules/gene. Most genes have transcription rates of between 2 and 30 mRNAs/hour and less than 1% of yeast genes have >1 RNA polymerase molecule/gene. Histone and ribosomal protein genes are the highest transcribed groups of genes and other than these exceptions the transcription of genes is an infrequent phenomenon in a yeast cell

    Genetic variability and structure of jaguar (Panthera onca) in Mexican zoos

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    ArtículoGenealogical records of animals (studbook) are created to avoid reproduction between closely related individuals, which could cause inbreeding, particularly for such endangered species as the Panthera onca (Linnaeus, 1758). Jaguar is the largest felid in the Americas and is considered an important ecological key species. In Mexico, wild jaguar populations have been significantly reduced in recent decades, and population decline typically accompany decreases in genetic variation. There is no current census of captive jaguars in Mexico, and zoos do not follow a standardized protocol in breeding programs based on genetic studies. Here, we emphasise the importance of maintaining an adequate level of genetic variation and propose the implementation of standardised studbooks for jaguars in Mexico, mainly to avoid inbreeding. In addition, achieving the aims of studbook registration would provide a population genetic characterisation that could serve as a basis for ex situ conservation programmes
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