1,916 research outputs found

    Modelling the spatial variation of vital rates: An evaluation of the strengths and weaknesses of correlative species distribution models

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    P. 841-853Aim: Species distribution models based on breeding occurrence data allow for identifying both environmental drivers and geographic areas potentially relevant for breeding. However, the interpretation of model predictions in terms of reproductive performance should be further investigated, as this information is crucial for conservation planning. We evaluated the strengths and weaknesses of a correlative modelling approach based on breeding occurrence data (presence–absence) against another approach based on vital rates’ data (breeding success) for gaining insights on species persistence in the case of Great Bustards (Otis tarda). Location: Spain. Methods: Breeding occurrence and breeding success were independently modelled using generalized linear models and multimodel inference analyses. Sensitivities to the way in which the population parameter (breeding success) was defined were explored by building five versions of the dependent variable. We evaluated differences in model performance and identified areas of congruence for breeding occurrence and breeding success. Results: The agreement between the spatial predictions achieved by breeding occurrence and breeding success models differed substantially across databases, with the largest differences in occupied breeding areas. The deviance explained by the breeding occurrence model was 64.98% and ranged from 7.83% to 62.27% for the breeding success models. Model performance was higher for models calibrated within potential than within occupied breeding areas. Main conclusions: The combination of data on both breeding occurrence and breeding success into a species distribution modelling framework showed the limitations of breeding occurrence models for inferring reproductive parameters. The definition of the population parameter as dependent variable was a key factor that strongly affected the inference of vital rates’ models. The approach allowed for discriminating between areas and landscape attributes necessary for the long-term species persistence from others that may be relevant, but not so much for reproductive performance

    Trastornos pódales en bovinos de sistemas de producción doble propósito en el Departamento Córdoba, Colombia

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    The objetive was determining the frequency of pedal upheavals in double purpose bovines in the Córdoba department. A study was done of cross section using 170 greater cows of three year selected at random in different property which were evaluated by means of the accomplishment of the clinical examination of the hooves, determining normality or then abnormality that these displayed and in agreement with the found injury, it was identified and characterized. The frequency of pedals upheavals in Córdoba department was of 64.70% of the total of the studied sample. 30.59% of the studied animals displayed alteration of the relation 2:1 wall-heel and 47.05 % displayed some type of podal pathology. The found pedals pathologies were: Hoof in corkscrew (36.47%), digital granuloma (17.06%), septic pododermatitis (4.71%) and interdigital callus (2.35%) the incidence of lameness was of 78.75% with respect to the animals that displayed pathologies and 37.05% with relation to the total of the sample. In addition was dependency between the type of land with relation to the podal upheaval and independence between podales adjustments and presence of footbaths with relation to the podal adjustment.El Objetivo fue determinar la frecuencia de trastornos pódales en bovinos doble propósito en el Departamento de Córdoba. Se hizo un estudio de corte transversal utilizando 170 vacas mayores de tres años escogidas al azar en diferentes fincas del departamento de Córdoba, Colombia, las cuales fueron evaluadas mediante la realización del examen clínico general y del sistema locomotor, con énfasis en la evaluación de las pezuñas, determinando la normalidad o anormalidad que presentaron estas y de acuerdo con la lesión encontrada se identifico dicho trastorno. La frecuencia de trastornos pódales en el Departamento de Córdoba fue del 64,70% del total de la muestra estudiada. El 30,59% de los animales estudiados presentaron alteración de la relación 2:1 muralla-talón y el 47,05% presentaron algún tipo de patología podal. Las patologías pódales encontradas fueron: Pezuña en tirabuzón (36,47%), Granuloma digital (17,06%), Pododermatitis séptica (4,71%) y Callo interdigital (2,35%). La incidencia de cojeras fue del 78,75% con respecto a los animales que presentaron patologías y de 37,05% con relación al total de la muestra. Además se encontró dependencia entre el tipo de terreno con relación al trastorno podal e independencia entre arreglos pódales y presencia de pediluvios con relación al trastorno podal

    Surface-Enhanced Raman Scattering Detection of Nucleic Acids Exhibiting Sterically Accessible Guanines Using Ruthenium-Polypyridyl Reagents

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    This is the peer reviewed version of the following article: Martínez-Calvo, M.; Guerrini, L.; Rodríguez, J.; Álvarez Puebla, R. A.; Mascareñas, J. L. (2020), Surface-enhanced Raman Scattering Detection of Nucleic Acids exhibiting Sterically Accessible Guanines using Ruthenium-polypyridyl Reagents. J. Phys. Chem. Lett., 11: 7218–7223, which has been published in final form at https://doi.org/10.1021/acs.jpclett.0c02148. This article may be used for non-commercial purposes in accordance with ACS Terms and Conditions for Use of Self-Archived VersionsHere, we report the application of surface-enhanced Raman scattering (SERS) spectroscopy as a rapid and practical tool for assessing the formation of coordinative adducts between nucleic acid guanines and ruthenium polypyridyl reagents. The technology provides a practical approach for the wash-free and quick identification of nucleic acid structures exhibiting sterically accessible guanines. This is demonstrated for the detection of a quadruplex-forming sequence present in the promoter region of the c-myc oncogene, which exhibits a nonpaired, reactive guanine at a flanking position of the G-quartetsWe are thankful for the financial support from the Xunta de Galicia (Centro singular de investigación de Galicia accreditation 2019-2022, ED431G 2019/03) and the European Union (European Regional Development Fund – ERDF). We also acknowledge the support given by the Spanish Grant SAF2013-41943-R and SAF2016-76689-R, the Xunta de Galicia (Grants 2015-CP082, ED431C 2017/19,), the Spanish Ministry de Economia y Competitividad (CTQ2017-88648R and RYC-2016-20331), the Generalitat de Cataluña (2017SGR883), the Universitat Rovira i Virgili (2019PFR-URV-B2-02), the Universitat Rovira i Virgili and Banco Santander (2017EXIT-08), and the European Research Council (Advanced Grant No. 340055). M.M.-C. thanks the Ministerio de Economı́a y Competitividad for the Postdoctoral fellowship (IJCI-2014-19326) and the Ministerio de Ciencia e Innovación and Ministerio de Universidades for the Distinguished Researcher contract “Beatriz Galindo” (BEAGAL18/00144). J.R. thanks Xunta de Galicia for her predoctoral fellowshipS

    Recent Overview of Solar Photocatalysis and Solar Photo-Fenton Processes for Wastewater Treatment

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    This literature research, although not exhaustive, gives perspective to solar-driven photocatalysis, such as solar photo-Fenton and TiO2 solar photocatalysis, reported in the literature for the degradation of aqueous organic pollutants. Parameters that influence the degradation and mineralization of organics like catalyst preparation, type and load of catalyst, catalyst phase, pH, applied potential, and type of organic pollutant are addressed. Such parameters may also affect the photoactivity of the catalysts used in the studied solar processes. Solar irradiation is a renewable, abundant, and pollution-free energy source for low-cost commercial applications. Therefore, these solar processes represent an environmentally friendly alternative mainly because the use of electricity can be decreased/avoided

    Sprachenpolitik als Sicherheitsproblem in der Ukraine

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    This paper presents the design, implementation, and measurements of a complete electronic frontend intended for high-resolution spatial detection of ion beams at counting rates higher than 106 particles per second (p/s). The readout system is made up of three main multichannel building blocks, namely, a transimpedance preamplifier, a signal-conditioning line receiver, and a charge-to-digital converter, as well as some off-the-shelf components. The preamplifier and the line receiver have been specifically designed and optimized to minimize the overlapping probability of ion beams tracking, at high counting rates, in low-pressure gaseous secondary electron detectors. Experimental results are shown, considering α particles sources and particles beams, featuring an adaptive shaping time frame of 170-230 ns with a peak signal-to-noise ratio of up to 25 dB. These performance metrics are competitive with the state of the art, demonstrating the suitability of the reported data acquisition and instrumentation system for precise and fast particle tracking detection

    Persistence and intensity of soil water repellency from soils with andic properties from the Campania region (Southwest, Italy) under different forest types

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    Congreso celebrado del 2-6, julio, 2012, en Fiera del Levante, Bari, Italia.Soil water repellency (SWR) is a property of many soils that is getting more and more interesting for the scientific community, because of its consequences on soil erosion risk, runoff or infiltration rates and even plant ecology. The presence of hydrophobic organic acids released by roots and plant tissues, fungal activity, organic matter mineralization rates, or wildfires are considered the main causes of SWR. Some of the consequences of SWR are reduced soil infiltration rates, enhanced runoff flow and soil erosion. Significance of these effects depends upon the severity and spatial variability of SWR. SWR is often associated to vegetation types, although it cannot be assumed that certain species always induce water repellency under natural conditions. Because of resins, waxes and aromatic oils in their tissues, evergreen trees as eucalyptus and coniferous are usually associated with soil hydrophobicity, although it has been found also in a variety of soils, climates and vegetation types. But the relationship between water repellent soils and plant species is not always one-to-one. Soil properties as texture, aggregation, acidity, microbiome and other are also implied in the development of hydrophobicity. Regarding organic matter, several authors have reported inconsistent results after studying the relationship between soil organic matter content and SWR. A possible explanation for this is that quality of organic matter is more important than content. Consequently, it is necessary to investigate the role that organic matter content and properties play in the development of hydrophobicity in different soil and vegetation types. The objective of this research is the study the relationship between SWR and organic matter properties in andic soils from the Campania region (SW Italy) under different vegetation types.Peer reviewe

    Comparative Field Trial Effect of <em>Brucella</em> spp. Vaccines on Seroconversion in Goats and Their Possible Implications to Control Programs

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    The aim of this study was to determine the seroprevalence of Brucella spp. in a goat flock and the seroconversion of three groups of animals vaccinated with Rev-1 (Brucella melitensis), RB51, and RB51-SOD (Brucella abortus) to estimate the level of protection conferred on susceptible females. Seventy-two animals were used by group. Goats were older than 3 months, seronegative to brucellosis, not vaccinated previously, and kept within positive flocks. Vaccinated animals received 2 mL of product subcutaneously in the neck region. The first block was injected with Rev-1; the second received RB51, and the third group was injected with RB51-SOD. Follow-up sampling was performed at 30, 60, 90, and 365 days postvaccination. The general prevalence of brucellosis for the three groups was 1.2% (95%CI:0.5–2.7). The seroconversion rate by day 30 after vaccination was 77.7% (95%CI:61.9–88.2) for goats vaccinated with Rev-1. At 365 days post vaccination, the percentage of seropositive goats declined to 13.8% (95%CI:6.0–28.6). At day 365 after vaccination, 2.7% (95%CI:0.4–14.1) and 5.5% (95%CI:1.5–18.1) of animals vaccinated with RB51 and RB51-SOD, respectively, became positive. Results show that the seroconversion induced by Brucella abortus RB51 and RB51-SOD vaccines is lower than that by Brucella melitensis Rev-1

    Magneto-caloric effect in the pseudo-binary intermetallic YPrFe17 compound

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    We have synthesized the intermetallic YPrFe17 compound by arc-melting. X-ray and neutron powder diffraction show that the crystal structure is rhombohedral with View the MathML source space group (Th2Zn17-type). The investigated compound exhibits a broad isothermal magnetic entropy change {\Delta}SM(T) associated with the ferro-to-paramagnetic phase transition (TC \approx 290 K). The |{\Delta}SM| (\approx 2.3 J kg-1 K-1) and the relative cooling power (\approx 100 J kg-1) have been calculated for applied magnetic field changes up to 1.5 T. A single master curve for {\Delta}SM under different values of the magnetic field change can be obtained by a rescaling of the temperature axis. The results are compared and discussed in terms of the magneto-caloric effect in the isostructural R2Fe17 (R = Y, Pr and Nd) binary intermetallic alloys.Comment: Preprint, 5 pages (postprint), 4 figures, regular pape

    Instructional Changes Adopted for an Engineering Course: Cluster Analysis on Academic Failure

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    As first-year students come from diverse backgrounds, basic skills should be accessible to everyone as soon as possible. Transferring such skills to these students is challenging, especially in highly technical courses. Ensuring that essential knowledge is acquired quickly promotes the student’s self-esteem and may positively influence failure rates. Metaphors can help do this. Metaphors are used to understand the unknown. This paper shows how we made a turn in student learning at the University of Almeria. Our hypothesis assumed that metaphors accelerate the acquisition of basic knowledge so that other skills built on that foundation are easily learned. With these goals in mind, we changed the way we teach by using metaphors and abstract concepts in a computer organisation course, a technical course in the first year of an information technology engineering degree. Cluster analysis of the data on collective student performance after this methodological change clearly identified two distinct groups. These two groups perfectly matched the before and after scenarios of the use of metaphors. The study was conducted during 11 academic years (2002/2003 to 2012/2013). The 475 observations made during this period illustrate the usefulness of this change in teaching and learning, shifting from a propositional teaching/learning model to a more dynamic model based on metaphors and abstractions. Data covering the whole period showed favourable evolution of student achievement and reduced failure rates, not only in this course, but also in many of the following more advanced courses.The paper is structured in five sections. The first gives an introduction, the second describes the methodology. The third section describes the sample and the study carried out. The fourth section presents the results and, finally, the fifth section discusses the main conclusions

    Compression system for the phonocardiographic signal

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    An FPGA-based approach is proposed for implementing a compression system developed specifically for the signal of phonocardiogram. The compression method offers better rate and distorsion than standard audio compression techniques. Both the algorithm and the details on the solutions adopted for its implementation are presented in this paper.This work has been supported by Ministerio de Ciencia y Tecnología of Spain, under grant TIN2006-15460-C04-04
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