307 research outputs found

    WHAT IS THE LENGTH OF A SNAKE?

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    The way that herpetologists have traditionally measuredlive snakes is by stretching them on a ruler andrecording the total length (TL). However, due to the thinconstitution of the snake, the large number of intervertebraljoints, and slim muscular mass of most snakes,it is easier to stretch a snake than it is to stretch anyother vertebrate. The result of this is that the length ofa snake recorded is infl uenced by how much the animalis stretched. Stretching it as much as possible is perhapsa precise way to measure the length of the specimenbut it might not correspond to the actual length ofa live animal. Furthermore, it may seriously injure a livesnake. Another method involves placing the snake in aclear plexiglass box and pressing it with a soft materialsuch as rubber foam against a clear surface. Measuringthe length of the snake may be done by outlining itsbody with a string (Fitch 1987; Frye 1991). However, thismethod is restricted to small animals that can be placedin a box, and in addition, no indications of accuracy of thetechnique are given. Measuring the snakes with a fl exibletape has also been reported (Blouin-Demers 2003)but when dealing with a large animals the way the tapeis positioned can produce great variance on the fi nal outcome.In this contribution we revise alternative ways tomeasuring a snake and propose a method that offers repeatableresults. We further analyze the precision of thismethod by using a sample of measurements taken fromwild populations of green anacondas (Eunectes murinus)with a large range of sizes

    Clasificacion de productos a traves de analisis cluster en una empresa del rubro automotriz

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    128 p.La información que es posible generar en toda organización resulta ser muy importante para llevar a cabo una adecuada toma de decisiones, lo cual es una tarea vital para cualquier empresa que desea mantenerse en el tiempo. En ese sentido, el cómo puede adquirirse información en base a los datos generados por las actividades realizadas por un área específica, torna de ideas y respuestas no siempre aplicables totalmente. En el presente trabajo se lleva a cabo una metodología de Análisis Cluster, basada en los conceptos del estudio multivariante que permite examinar diferentes características de objetos, en este caso, productos del rubro automotriz. El objetivo es establecer una clasificación, agrupando los artículos más parecidos entre sí, con el fin de interpretar los grupos generados para así obtener información desconocida hasta el momento. Los resultados del proyecto representan una excelente guía, tanto para replicar estudios similares como para generar estrategias a futuro. Se realiza la selección de un método de clasificación mixto que permite solucionar ciertos problemas, que permiten un resultado favorable y novedoso. Obteniendo así un horizonte novedoso para agrupaciones existentes en la empresa

    Monitoring of SARS-CoV-2 seroprevalence among primary healthcare patients in the Barcelona Metropolitan Area: the SeroCAP sentinel network protocol

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    COVID-19; Epidemiology; Primary careCOVID-19; Epidemiología; Atención primariaCOVID-19; Epidemiologia; Atenció primàriaIntroduction SARS-CoV-2 seroprevalence studies are currently being recommended and implemented in many countries. Forming part of the COVID-19 monitoring and evaluation plan of the Catalan Government Health Department, our network aims to initiate a primary healthcare sentinel monitoring system as a surrogate of SARS-CoV-2 exposure in the Barcelona Metropolitan Area. Methods and analysis The seroCAP is a serial cross-sectional study, which will be performed in the Barcelona Metropolitan Area to estimate antibodies against SARS-CoV-2. From February 2021 to March 2022, the detection of serum IgG antibodies against SARS-CoV-2 trimeric spike protein will be performed on a monthly basis in blood samples collected for diverse clinical purposes in three reference hospitals from the three Barcelona healthcare areas (BCN areas). The samples (n=2588/month) will be from patients attended by 30 primary healthcare teams at 30 basic healthcare areas (BHA). A lab software algorithm will systematically select the samples by age and sex. Seroprevalence will be estimated and monitored by age, sex, BCN area and BHA. Descriptive and cluster analysis of the characteristics and distribution of SARS-CoV-2 infections will be performed. Sociodemographic, socioeconomic and morbidity-associated factors will be determined using logistic regression. We will explore the association between seroprevalence, SARS-CoV-2 confirmed cases and the implemented measures using interrupted time series analysis. Ethics and dissemination Ethical approval was obtained from the University Institute Foundation for Primary Health Care Research Jordi Gol i Gurina ethics committee. An informed consent is not required regarding the approval of the secondary use of biological samples within the framework of the COVID-19 pandemic. A report will be generated quarterly. The final analysis, conclusions and recommendations will be shared with the stakeholders and communicated to the general public. Manuscripts resulting from the network will be submitted for publication in peer-reviewed journals.This work will be supported by the Health Department of the Government of Catalunya (No grant number)

    La cultura profesional de los docentes en enseñanza secundaria: Un estudio biográfico.

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    This work discusses the "voices" of teachers working "at the chalk face." We are interested in learning what teachers think and how they behave. Therefore, we conducted our research about their working conditions. We also developed teachers" professional biographies to learn how these educators construct concepts and practices related to their profession and what constitutes their "professional culture". We understand that thie professional culture characterizes teachers" professional frameworks and choices; therefore, any attempt to successfully promote an educational reform, must understand and pay attention to the "professional culture."Este trabajo trata sobre las "voces" de los profesores que trabajan "a pie de obra". Nos interesa aprender qué piensan los profesores y cómo se comportan. Para ello se ha llevado a cabo una investigación en sus propios contextos de trabajo. De este modo, elaboramos sus biografías profesionales para aprender como han ido construyendo estos conceptos y prácticas profesionales y, de este modo, aprender qué es lo que constituye su "cultura profesional". Entendemos que es esta cultura profesional la que determina las opciones de los profesores que caracteriza su estructura profesional y por tanto, cualquier intento de afrontar una reforma educativa necesariamente tiene que atender y entender estas estructuras

    Melatonin-doped polymeric nanoparticles induce high crystalline apatite formation in root dentin

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    This work was funded by the Ministry of Economy and Competitiveness and European Regional Development Fund( MINECO/AEI/FEDER/UE) Project number PID2020-114694RBI00. Funding for open access charge: University of Granada / CBUA.Objective. To investigate the effect of novel polymeric nanoparticles (NPs) doped with melatonin (ML) on nano-hardness, crystallinity and ultrastructure of the formed hydroxyapatite after endodontic treatment. Methods. Undoped-NPs and ML-doped NPs (ML-NPs) were tested at radicular dentin, after 24 h and 6 m. A control group without NPs was included. Radicular cervical and apical dentin surfaces were studied by nano-hardness measurements, X-ray diffraction and transmission electron microscopy. Mean and standard deviation were analyzed by ANOVA and StudentNewman-Keuls multiple comparisons (p < 0.05). Results. Cervical dentin treated with undoped NPs maintained its nano-hardness values after 6 m of storage being [24 h: 0.29 (0.01); 6 m: 0.30 (0.02) GPa], but it decreased at apical dentin [24 h: 0.36 (0.01); 6 m: 0.28 (0.02) GPa]. When ML-NPs were used, nano-hardness was similar over time [24h: 0.31 (0.02); 6 m: 0.28 (0.03) GPa], at apical dentin. Root dentin treated with ML-NPs produced, in general, high crystallinity of new minerals and thicker crystals than those produced in the rest of the groups. After 6 m, crystals became organized in randomly oriented polyhedral, square polygonal block-like apatite or drop-like apatite polycrystalline lattices when ML-NPs were used. Undoped NPs generated poor crystallinity, with preferred orientation of small crystallite and increased microstrain. Significance. New polycrystalline formations encountered in dentin treated with ML-NPs may produce structural dentin stability and high mechanical performance at the root. The decrease of mechanical properties over time in dentin treated without NPs indicates scarce remineralization potential, dentin demineralization and further potential degradation. The amorphous stage may provide high hydroxyapatite solubility and remineralizing activity.Ministry of Economy and Competitiveness and European Regional Development Fund( MINECO/AEI/FEDER/UE) PID2020-114694RB-I00University of Granada/CBU

    Dual Role of p53 in Innate Antiviral Immunity

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    Tumor suppressor p53 is widely known as ‘the guardian of the genome’ due to its ability to prevent the emergence of transformed cells by the induction of cell cycle arrest and apoptosis. However, recent studies indicate that p53 is also a direct transcriptional target of type I interferons (IFNs) and thus, it is activated by these cytokines upon viral infection. p53 has been shown to contribute to virus-induced apoptosis, therefore dampening the ability of a wide range of viruses to replicate and spread. Interestingly, recent studies also indicate that several IFN-inducible genes such as interferon regulatory factor 9 (IRF9), IRF5, IFN-stimulated gene 15 (ISG15) and toll-like receptor 3 (TLR3) are in fact, p53 direct transcriptional targets. These findings indicate that p53 may play a key role in antiviral innate immunity by both inducing apoptosis in response to viral infection, and enforcing the type I IFN response, and provide a new insight into the evolutionary reasons why many viruses encode p53 antagonistic proteins

    From early contraction to post-folding fluid evolution in the frontal part of the boixols thrust sheet (southern pyrenees) as revealed by the texture and geochemistry of calcite cements

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    Structural, petrological and geochemical (δ13C, δ18O, clumped isotopes, 87Sr/86Sr and ICP-MS) analyses of fracture-related calcite cements and host rocks are used to establish a fluid-flow evolution model for the frontal part of the Bóixols thrust sheet (Southern Pyrenees). Five fracture events associated with the growth of the thrust-related Bóixols anticline and Coll de Nargó syncline during the Alpine orogeny are distinguished. These fractures were cemented with four generations of calcite cements, revealing that such structures allowed the migration of different marine and meteoric fluids through time. During the early contraction stage, Lower Cretaceous seawater circulated and precipitated calcite cement Cc1, whereas during the main folding stage, the system opened to meteoric waters, which mixed with the connate seawater and precipitated calcite cement Cc2. Afterwards, during the post-folding stages, connate evaporated marine fluids circulated through newly formed NW-SE and NE-SW conjugate fractures and later through strike-slip faults and precipitated calcite cements Cc3 and Cc4. The overall paragenetic sequence reveals the progressive dewatering of Cretaceous marine host sediments during progressive burial, deformation and fold tightening and the input of meteoric waters only during the main folding stage. This study illustrates the changes of fracture systems and the associated fluid-flow regimes during the evolution of fault-associated folds during orogenic growth

    Implementation of herd health program to improve survival of Boer goats in Malaysia.

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    A Boer goat breeding farm with 800 heads of breeder females, 50 breeder males, and 400 growing goats of various ages in Sabah, Malaysia was selected to study the effect of implementing herd health program. This included vaccination program against pneumonic mannheimiosis; fecal monitoring for helminthiasis, coccidiosis, and colibacillosis; and introduction of modified feeding regime comprised of day-time grazing and feeding of cut grass and supplemented feed. The herd health program was implemented in September 2007 and the impact was observed on body weight gains, body scoring, and annual mortality among adults and kids. It was found that implementation of herd health program significantly (p<0. 05) increased the average body weight gains in both adults and kids from 1. 8 g per kid and 0. 6 g per adult in 2006 to 3. 7 g per kid and 2. 2 g per adult in 2008. The percentage of adults with body scoring of <3 was significantly (p<0. 05) reduced from 82. 3% in 2006 to 77. 6% in 2007 and 4% in 2008. Similarly, the annual mortality rate was significantly (p<0. 05) reduced from 6. 5% among kids and 58. 2% among adults in 2006 to 12. 1% among kids and 10. 4% among adults in 2007, and to 9. 1% among kids and 1. 1% among adults in 2008. Therefore, it was concluded that implementation of herd health program significantly improved the survival and performance of goats

    Synthesis of phosphonate-functionalized polystyrene and poly(methyl methacrylate) particles and their kinetic behavior in miniemulsion polymerization

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    Phosphonate-functionalized polymer nanoparticles were synthesized by free-radical copolymerization of vinylphosphonic acid (VPA) with styrene or methyl methacrylate (MMA) using the miniemulsion technique. The influence of different parameters such as monomer and surfactant type, amount of vinylphosphonic acid on the average particle size, and size distribution was studied using dynamic light scattering and transmission electron microscopy. Depending on the amount and type of the surfactant used (ionic or non-ionic), phosphonate-functionalized particles in a size range from 102 to 312 nm can be obtained. The density of the phosphonate groups on the particle surface was higher in the case of using MMA as a basis monomer than polystyrene. The kinetic behavior of VPA copolymerization with styrene or MMA using a hydrophobic initiator was investigated by reaction calorimetry. Different kinetic curves were observed for miniemulsion (co)polymerization of styrene- and MMA-based nanoparticles indicating different nucleation mechanisms

    Pulmonary nodules in African migrants caused by chronic schistosomiasis

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    Schistosomiasis is a neglected tropical disease that can cause mainly hepatic and genitourinary damage, depending on the species. Involvement of the lungs has been commonly described in acute infection (Katayama syndrome) and chronic infection (pulmonary hypertension). Although rarely reported in the scientific literature, cases of lung nodules due to chronic schistosome infection are also possible and are probably more frequent than commonly thought. Here we report seven cases of African migrants who were diagnosed with chronic schistosomiasis and pulmonary nodules due to deposition of schistosome eggs, and we compare our findings to the case reports found in the scientific literature. We discuss the management of these patients in a non-endemic setting, beginning with a first fundamental step that is to include parasitic infections, namely schistosomiasis, in the differential diagnosis of pulmonary nodules in African immigrants. All patients responded to antiparasitic treatment with praziquantel after a relatively short time. We therefore conclude that lung biopsies and other invasive procedures (performed in the first cases to rule out other potential causes, such as tuberculosis or malignant nodules) can be avoided or postponed
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