132 research outputs found
Influencia de las condiciones físicas y químicas de un oxisol de la Altillanura Colombiana sobre los rendimientos de maíz, Carimagua, Meta, Colombia.
Maíz-Zea may
AUTOMATIZACIÓN DE LA ETAPA DE CORTE DE UNA EXTRUSORA DE PLÁSTICO TERMOFIJO (AUTOMATION OF THE CUTTING STAGE OF A TERMOFIJO PLASTIC EXTRUDER)
En este artículo se presenta el diseño y la implementación de la automatización del sistema de corte para una extrusora de una empresa fabricante de plástico termofijo. El material producido por esta máquina es una pasta la cual es moldeada para que tome la forma de un cilindro continuo. Por requerimientos de los clientes, el material tiene que ser cortado en porciones de longitud determinada, antes de ser empacado. A su vez, dependiendo del tipo de material producido es necesario emplear diferentes mecanismos de corte. El sistema de control de corte diseñado está basado en un Controlador Lógico Programable y cuenta con tres modos distintos de operación. La configuración del sistema la realiza el operador mediante una interfaz diseñada para este fin. Por medio de una serie de menús que se despliegan en una pantalla LCD y con ayuda de un teclado, es posible elegir el método de corte a utilizar. Las etapas de diseño y construcción son presentadas, así como el resultado obtenido. El sistema tiene 24 meses operando adecuadamente necesitando únicamente el mantenimiento normal asociado a equipos industriales. El beneficio para la empresa se reflejó en una menor cantidad de piezas fuera de especificación, así como en la reducción del tiempo de paro relacionado con el cambio de tipo de corte.This paper, presents the design and implementation of the automation of the cutting system of an extruder of a plastic manufacturer. The material produced by this machine is a paste which is molded to take the form of a continuous cylinder. For customer requirements, the material has to be cut into portions of determined length, before being packed. In turn, depending on the type of material produced it is necessary to use different cutting mechanisms. The cutting control system designed is based on a Programmable Logic Controller and it has three operation modes. System configuration is performed through an interface designed for this purpose. The cutting method to be used is selected by means of a keyboard and a series of menus that are displayed on an LCD screen. The design and construction stages are presented, as well as the result obtained. The system has 24 months operating properly, needing only the normal maintenance associated with industrial equipment. The benefit for the company was reflected in a smaller number of parts out of specification, as well as in the reduction of the time of unemployment related to the change of type of cut
Development and sedative effect of a new formulation of midazolam in chocolate bars
The aim of this work was to assess the stability and sedative effect of midazolam in chocolate bars. The stability of 5 g chocolate bars containing 6 mg midazolam hydrochloride was evaluated at room temperature (25 ± 2 °C), at 4 and 40 °C, by HPLC. Drug plasma levels were measured and the sedative effect was confirmed in six healthy volunteers according to the Ramsay’s scale. Data regarding chocolate bar administration were compared to those from the apple juice solution. Pharmacokinetic data were processed using the WinNonLin 5.2 software. Midazolam in chocolate bars remained stable for 14 days at room temperature and exposed to light; for 90 days at 4 and 40 °C protected from light, and showed a longer shelf life, better flavour and appearance, inducing the same sedative effect as the apple juice preparation. Raspberry flavour masked midazolam unpleasing taste most favourably.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Applied science facilitates the large-scale expansion of protected areas in an Amazonian hot spot
Meeting international commitments to protect 17% of terrestrial ecosystems worldwide will require \u3e3 million square kilometers of new protected areas and strategies to create those areas in a way that respects local communities and land use. In 2000–2016, biological and social scientists worked to increase the protected proportion of Peru’s largest department via 14 interdisciplinary inventories covering \u3e9 million hectares of this megadiverse corner of the Amazon basin. In each landscape, the strategy was the same: convene diverse partners, identify biological and sociocultural assets, document residents’ use of natural resources, and tailor the findings to the needs of decision-makers. Nine of the 14 landscapes have since been protected (5.7 million hectares of new protected areas), contributing to a quadrupling of conservation coverage in Loreto (from 6 to 23%). We outline the methods and enabling conditions most crucial for successfully applying similar campaigns elsewhere on Earth
Development and sedative effect of a new formulation of midazolam in chocolate bars
The aim of this work was to assess the stability and sedative effect of midazolam in chocolate bars. The stability of 5 g chocolate bars containing 6 mg midazolam hydrochloride was evaluated at room temperature (25 ± 2 °C), at 4 and 40 °C, by HPLC. Drug plasma levels were measured and the sedative effect was confirmed in six healthy volunteers according to the Ramsay’s scale. Data regarding chocolate bar administration were compared to those from the apple juice solution. Pharmacokinetic data were processed using the WinNonLin 5.2 software. Midazolam in chocolate bars remained stable for 14 days at room temperature and exposed to light; for 90 days at 4 and 40 °C protected from light, and showed a longer shelf life, better flavour and appearance, inducing the same sedative effect as the apple juice preparation. Raspberry flavour masked midazolam unpleasing taste most favourably.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Giardia duodenalis: analysis of secreted proteases upon trophozoite-epithelial cell interaction in vitro
Consenso mexicano sobre probióticos en gastroenterología
Introducción: El uso de los probióticos es común en la práctica clínica. Existe un número signi-ficativo de estudios que apoyan la eficacia de los probióticos en algunos trastornos digestivos.Sin embargo, el desconocimiento de la evidencia científica y las diferentes presentaciones ycomposiciones microbianas de los probióticos disponibles dificultan su prescripción.Objetivo: Proveer al clínico de una revisión consensuada sobre los probióticos y recomendacio-nes de su uso en gastroenterología.Material y métodos: Se seleccionaron los ensayos clínicos controlados, metaanálisis y revisio-nes sistemáticas publicados hasta 2015, usando los términos MESH: probiotics, gastrointestinaldiseases, humans, adults and children. Se utilizó la metodología Delphi. Diecisiete gastroente-rólogos de adultos y 12 de ni˜nos elaboraron enunciados los cuales fueron votados hasta obteneracuerdo > 70%. Para cada enunciado se evaluó el nivel de evidencia basado en el sistema GRADE.Resultados y conclusiones: Se generaron 11 enunciados sobre conceptos generales de probió-ticos y 27 enunciados sobre uso de probióticos en enfermedades gastrointestinales tanto enni˜nos como en adultos. El grupo de consenso recomienda el uso de probióticos en las siguientescondiciones clínicas: prevención de la diarrea asociada a antibióticos, tratamiento de la diarreaaguda infecciosa, prevención de infección por Clostridium difficile y enterocolitis necrosante,para disminuir los eventos adversos de la terapia de erradicación del Helicobacter pylori, elalivio de los síntomas del síndrome de intestino irritable, en el estre˜nimiento funcional deladulto, para inducir y mantener la remisión en pacientes con colitis ulcerosa crónica idiopáticay pouchitis, y en la encefalopatía hepática oculta y manifiesta.© 2016 Asociaci´on Mexicana de Gastroenterolog´ıa. Publicado por Masson Doyma M´exico S.A.Este es un art´ıculo Open Access bajo la licencia CC BY-NC-ND (http://creativecommons.org/licenses/by-nc-nd/4.0/).
ASTRACT
Introduction: Probiotics are frequently prescribed in clinical practice. Their efficacy in treatinggastrointestinal disorders is supported by a significant number of clinical trials. However, thecorrect prescription of these agents is hampered due to a lack of knowledge of the scientificevidence and to the different presentations and microbial compositions of the probiotics thatare currently available.Aim: To provide the clinician with a consensus review of probiotics and recommendations fortheir use in gastroenterology.Materials and methods: Controlled clinical trials, meta-analyses, and systematic reviewspublished up to 2015 were selected, using the MESH terms: probiotics, gastrointestinal diseases,humans, adults, AND children. The Delphi method was employed. Eighteen gastroenterologiststreating adult patients and 14 pediatric gastroenterologists formulated statements that werevoted on until agreement > 70% was reached. The level of evidence based on the GRADE systemwas evaluated for each statement.Results and conclusions: Eleven statements on the general concepts of probiotics and 27 sta-tements on the use of probiotics in gastrointestinal diseases in both adults and children wereformulated. The consensus group recommends the use of probiotics under the following clini-cal conditions: the prevention of diarrhea associated with antibiotics, the treatment of acuteinfectious diarrhea, the prevention of Clostridium difficile infection and necrotizing enteroco-litis, the reduction of adverse events from Helicobacter pylori eradication therapy, relief fromirritable bowel syndrome symptoms, the treatment of functional constipation in the adult, and the induction and maintenance of remission in patients with ulcerative colitis and pouchitis,and the treatment of covert and overt hepatic encephalopathy.© 2016 Asociaci´on Mexicana de Gastroenterolog´ıa. Published by Masson Doyma M´exico S.A. Thisis an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Global urban environmental change drives adaptation in white clover.
Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale
Early science with the Large Millimeter Telescope: a 1.1 mm AzTEC survey of red-<i>Herschel</i> dusty star-forming galaxies
We present Large Millimeter Telescope (LMT)/AzTEC 1.1 mm observations of ∼100 luminous high-redshift dusty star-forming galaxy candidates from the ∼600 sq.deg Herschel-ATLAS survey, selected on the basis of their SPIRE red far-infrared colours and with S500μm=35−80 mJy. With an effective θFWHM ≈ 9.5arcsec angular resolution, our observations reveal that at least 9 per cent of the targets break into multiple systems with signal-to-noise ratio ≥4 members. The fraction of multiple systems increases to ∼23 per cent (or more) if some non-detected targets are considered multiples, as suggested by the data. Combining the new AzTEC and deblended Herschel photometry, we derive photometric redshifts, infrared luminosities, and star formation rates. While the median redshifts of the multiple and single systems are similar (zmed ≈ 3.6), the redshift distribution of the latter is skewed towards higher redshifts. Of the AzTEC sources, ∼85 per cent lie at zphot > 3 while ∼33 per cent are at zphot > 4. This corresponds to a lower limit on the space density of ultrared sources at 4 −7Mpc−3 with a contribution to the obscured star formation of ≳8×10−4M⊙yr−1Mpc−3. Some of the multiple systems have members with photometric redshifts consistent among them suggesting possible physical associations. Given their angular separations, these systems are most likely galaxy over-densities and/or early-stage pre-coalescence mergers. Finally, we present 3 mm LMT/RSR spectroscopic redshifts of six red-Herschel galaxies at zspec = 3.85−6.03, two of them (at z ∼ 4.7) representing new redshift confirmations. Here, we release the AzTEC and deblended Herschel photometry as well as catalogues of the most promising interacting systems and z > 4 galaxies
Using the present to interpret the past: the role of ethnographic studies in Andean archaeology
Within Andean research it is common to use ethnographic analogies to aid the interpretation of archaeological remains, and ethnographers and archaeologists have developed shared research in technology, material culture and material practice. Although most of this research does not follow the detailed recording methods of spatial patterning envisioned in earlier formulations of ethnoarchaeology, it has had a profound effect on how archaeology in the region has been interpreted. This paper uses examples from the study of pottery production to address earlier debates about the use of ethnographic analogy, discusses the dangers of imposing an idealised or uniform vision of traditional Andean societies onto earlier periods (‘Lo Andino’) but stresses the benefits of combining ethnographic and archaeological research to explore continuities and changes in cultural practice and regional variations
- …