1,781 research outputs found
Dynamics of topsoil carbon stocks after prescribed burning for pasture restoration in shrublands of the Central Pyrenees (NE-Spain)
Prescribed burning has been recently readopted as a management practice in the Central Pyrenees (NE-Spain) to stop shrub encroachment processes and recover pasturelands. The immediate effects of prescribed burning on soil C stocks and related biological properties and their evolution in the short-to mid-term after burning were assessed. The study was conducted during three autumnal prescribed burnings in the Central Pyrenees in the municipalities of Buisán, Asín de Broto and Yebra de Basa. At each site, the topsoil Ah horizon was sampled at soil depths of 0-1, 1-2 and 2-3 cm immediately before and immediately after burning. Additionally, seasonal samplings were conducted every 6 months up to one year in the case of the Asín and Yebra sites and up to 24 months at the Buisán site. The total soil organic C stock (SOCS) total N stock (NS), microbial biomass C (MBC), soil basal respiration (SR) and β-D-glucosidase activity were analyzed. The maximum temperatures recorded at the soil surface were 438 °C (Buisán), 768 °C (Asín) and 595 °C (Yebra). At the Buisán site, burning significantly decreased the SOCS (-52%), NS (-44%), MBC (-57%), SR (-72%) and glucosidase activity (-66%) at 0-1 cm depth, whereas fire had no direct effects on soil at the Asín and Yebra sites. The contrasting effects of burning on soil that were observed among sites were found to be related to differences in fire residence time. The prescribed fire at the Buisán site was on a plain slope under slow winds (<8 km h-1) at a burning rate of 0.64 ha h-1, which produced greater impacts on the soil properties than the burnings at the Asín and Yebra sites, where fire spread rapidly (2.72 and 1.43 ha h-1, respectively). At the Buisán site, the SOCS and NS recovered to the unburned values 24 months after burning. One year after burning, the SOCS at Asín were 60% higher than those of the unburned soils at 0-1 cm depth. At all sites a decreasing trend in soil biological activity in the short- and mid-term was observed. From the results it can be concluded that: 1) the direct effects of burning on soil are highly dependent on the environmental conditions, 2) in the mid-term, the reduction in soil biological activity and the incorporation of ashes and charred plant remains led to an increase in the SOCS of the burned soils.publishe
Relationship between CEO’s strategic human capital and dynamic capabilities: a meta‑analysis
In this paper we study the association between Chief Executive Officers’ strategic
human resource capital, dynamic managerial capabilities, and firms’ dynamic capabilities.
This study identifies the Chief Executive Officer (CEO) variables reported in
the literature, and estimates the correlation of each CEO variable with the dynamic
capabilities. In addition, the moderator effect of the three types of dynamic capabilities
is estimated. This paper applies a meta-analysis using structural equation modeling
by means of the three-level random-effects model on 446 correlations, which
account for 52,767 CEOs around the world. The findings show a positive correlation
of CEO education (ρ = .113), CEO personality (ρ = .162), and leadership styles
(ρ = .306) with dynamic capabilities. In addition, dynamic managerial capabilities
totally mediate the relationship between education and dynamic capabilities and
partially the relationship of CEO personality and leadership styles with dynamic
capabilitiesThis study was supported by the Pontificia Universidad Javeriana and Administrative Department of Science, Technology and Innovation (Colciencias) in Colombi
Cross-Over between Discrete and Continuous Protein Structure Space: Insights into Automatic Classification and Networks of Protein Structures
Structural classifications of proteins assume the existence of the fold, which is an intrinsic equivalence class of protein
domains. Here, we test in which conditions such an equivalence class is compatible with objective similarity measures. We
base our analysis on the transitive property of the equivalence relationship, requiring that similarity of A with B and B with C
implies that A and C are also similar. Divergent gene evolution leads us to expect that the transitive property should
approximately hold. However, if protein domains are a combination of recurrent short polypeptide fragments, as proposed
by several authors, then similarity of partial fragments may violate the transitive property, favouring the continuous view of
the protein structure space. We propose a measure to quantify the violations of the transitive property when a clustering
algorithm joins elements into clusters, and we find out that such violations present a well defined and detectable cross-over
point, from an approximately transitive regime at high structure similarity to a regime with large transitivity violations and
large differences in length at low similarity. We argue that protein structure space is discrete and hierarchic classification is
justified up to this cross-over point, whereas at lower similarities the structure space is continuous and it should be
represented as a network. We have tested the qualitative behaviour of this measure, varying all the choices involved in the
automatic classification procedure, i.e., domain decomposition, alignment algorithm, similarity score, and clustering
algorithm, and we have found out that this behaviour is quite robust. The final classification depends on the chosen
algorithms. We used the values of the clustering coefficient and the transitivity violations to select the optimal choices
among those that we tested. Interestingly, this criterion also favours the agreement between automatic and expert
classifications. As a domain set, we have selected a consensus set of 2,890 domains decomposed very similarly in SCOP and
CATH. As an alignment algorithm, we used a global version of MAMMOTH developed in our group, which is both rapid and
accurate. As a similarity measure, we used the size-normalized contact overlap, and as a clustering algorithm, we used
average linkage. The resulting automatic classification at the cross-over point was more consistent than expert ones with
respect to the structure similarity measure, with 86% of the clusters corresponding to subsets of either SCOP or CATH
superfamilies and fewer than 5% containing domains in distinct folds according to both SCOP and CATH. Almost 15% of
SCOP superfamilies and 10% of CATH superfamilies were split, consistent with the notion of fold change in protein
evolution. These results were qualitatively robust for all choices that we tested, although we did not try to use alignment
algorithms developed by other groups. Folds defined in SCOP and CATH would be completely joined in the regime of large
transitivity violations where clustering is more arbitrary. Consistently, the agreement between SCOP and CATH at fold level
was lower than their agreement with the automatic classification obtained using as a clustering algorithm, respectively,
average linkage (for SCOP) or single linkage (for CATH). The networks representing significant evolutionary and structural
relationships between clusters beyond the cross-over point may allow us to perform evolutionary, structural, or functional
analyses beyond the limits of classification schemes. These networks and the underlying clusters are available at http://ub.cbm.uam.es/research/ProtNet.phpThis work was supported by the Ramon y Cajal program of the Spanish Science Ministry of Education and Science, Project ‘Centrosoma 3DBioinformatics’
of the program Consolider-Ingenio 2010 of the Spanish Ministry of Education and Science, Project BIO2005-0576 from the Spanish Ministry of Education and Science, Project 200520M157 from the Comunidad de Madrid, and Research Foundation ‘‘Ramon Areces’’.Peer reviewe
Meeting public health objectives and supporting the resumption of tourist activity through COVID-19: a triangular perspective
This work was supported by FEDER/Junta de AndalucAa-ConsejerAa de TransformaciA3n EconA3mica, Industria, Conocimiento y Universidades [grant number Project CV20-09357].Non-pharmaceutical interventions (NPIs) implemented during the COVID-
19 pandemic (and previous health crises) have included measures to
restrict interaction between people and minimize non-essential
mobility. Therefore, tourism travel is one of the main areas affected by
the restrictions. Even when the majority of the population is vaccinated,
some risk of infection will remain, and governments are obliged to
consider NPI measures that balance the health risk of outbreaks against
the economic and social benefits of resuming tourist activity. This study
analyzes the effect of each of four categories of NPIs (Social Distancing;
Public Healthcare-System Improvements; Tourist Controls; and Capacity
and Opening-Hours Regulation) on three major objectives (the
resumption of tourism activity; tourist travel intention; and the
minimization of public health risk), taking a triangular perspective
(destination managers, domestic tourists, and public healthcare
managers, respectively). While it is difficult to fulfil public healthcare
objectives while simultaneously responding to the economic interests
of tourism-industry stakeholders, the study finds that, under vaccinatedpopulation
conditions, tourist controls (e.g. COVID Certificate) alongside
improvements to the public healthcare system (e.g. adequate
resourcing and an efficient epidemiological monitoring system) could
constitute a viable combination of measures.FEDER/Junta de AndalucAa-ConsejerAa de TransformaciA3n EconA3mica, Industria, Conocimiento y Universidades CV20-0935
Influence of liquid-to-biogas ratio and alkalinity on the biogas upgrading performance in a demo scale algal-bacterial photobioreactor
The influence of the liquid-to-biogas ratio (L/G) and alkalinity on methane quality was evaluated in a 11.7 m3 outdoors horizontal semi-closed tubular photobioreactor interconnected to a 45-L absorption column (AC). CO2 concentrations in the upgraded methane ranged from <0.1 to 9.6% at L/G of 2.0 and 0.5, respectively, with maximum CH4 concentrations of 89.7% at a L/G of 1.0. Moreover, an enhanced CO2 removal (mediating a decrease in CO2 concentration from 9.6 to 1.2%) and therefore higher CH4 contents (increasing from 88.0 to 93.2%) were observed when increasing the alkalinity of the AC cultivation broth from 42 ± 1 mg L−1 to 996 ± 42 mg L−1. H2S was completely removed regardless of the L/G or the alkalinity in AC. The continuous operation of the photobioreactor with optimized operating parameters resulted in contents of CO2 (<0.1%–1.4%), H2S (<0.7 mg m−3) and CH4 (94.1%–98.8%) complying with international regulations for methane injection into natural gas grids.Peer ReviewedPostprint (published version
Dispositivo portátil de reproducción de documentos digitales en Braille
Publication number: ES2632185 A1 (11.09.2017)
Application number: P201600212 (10.03.2016)Dispositivo portátil de reproducción de documentos digitales en Braille, que es capaz de reproducir de manera autónoma y en alfabeto Braille cualquier tipo de documento digital que sea cargado en su memoria mediante un computador. Para la reproducción se utilizarán elementos electromagnéticos que permiten la representación los caracteres Braille, permitiendo así la lectura mediante el tacto. El dispositivo mostrará de manera visual mediante una pantalla, los caracteres que se están reproduciendo, además del estado de batería, volumen y configuración del tipo de reproducción. También tiene incorporado una matriz de led de 2x3 que simulan mediante su encendido, la reproducción en alfabeto Braille a la vez que lo hace el sistema táctil. Tiene incorporado un altavoz que reproduce en forma de audio los caracteres que se van reproduciendo. Para controlar el dispositivo, lleva incorporado un panel de botones con el que se puede cambiar de modo de reproducción o pausarla.Universidad de Almerí
The diplomacy of water: analysis of case “Río Bravo”
El presente artículo tiene como objetivo describir y comparar, a través de distintos casos,
la importancia de la diplomacia del agua en las Relaciones Internacionales. Se analiza la
disputa territorial del río Bravo entre México y Estados Unidos a través del Tratado de 1944.
Como antecedente, se exponen dos casos de investigación (disputas entre el río Mekong y el
Mar de la China Meridional), con el objetivo de sugerir soluciones para futuras problemáticas con base en las investigaciones existentes
Implementación de buenas prácticas de levante de ganado bovino en pequeños ganaderos ubicados en Santa Cruz de Lorica, Córdoba, basado en el modelo propuesto en la resolución 68167 de 2020 del Instituto Colombiano Agropecuario ICA
El presente proyecto de grado contiene el resultado obtenido a través de un
proceso de investigación mixta acerca del levante de ganado bovino, tomando
como punto de referencia el departamento de Córdoba, todo esto con el fin de
mejorar la calidad y productividad con la que se vienen realizando el proceso de
levante de ganado bovino.
En Colombia, la ganadería es bien conocida en las zonas rurales como una de sus
principales actividades comerciales. Este es el caso en la localidad de Lorica
Córdoba, que es la tercera con mayor población ganadera del país; Sin embargo,
es común observar que la mayoría de los criadores continúan realizando el
proceso de levántate de ganado con los conocimientos heredados en el pasado,
sin ningún tipo de regulación o guía mínima con los estándares recomendados.
Por tal motivo, la base principal de este nivel de proyecto es coadyuvar en la
optimización y desarrollo de estas prácticas, realizando orientaciones técnicas
basadas en el modelo de la resolución ICA68167.
Lo anterior se obtuvo mediante investigaciones, visitas a sitios y estudios,
entrevistas, revisiones extensas, revisiones de muestras y más para establecer la
mejor manera de desarrollar pautas para el beneficio de los ganaderos.
emocionados por su aplicación, ya que es complejo realizar cambios tecnológicos,
técnicos a una actividad que se ha venido realizando por años de manera
empírica, sin embargo, se obtendrá como resultado un proceso más optimo y de
calidadUniversidad Libre Seccional Barranquilla -- Facultad de Ingeniería -- Ingeniería IndustrialThe activities of breeding and hunting animals for man, is one of the most primitive methods of sustenance and food that is still maintained today. Today, like everything else, it has evolved and is what is known as livestock farming; these activities have been optimized, becoming increasingly efficient and profitable, not only for survival, but also for production and trade.
In Colombia, rural territories are characterized by having livestock as one of their main commercial activities. This is the case of the municipality of Lorica, located in Córdoba, which is the third department with the largest cattle population in the country; however, many of the cattle ranchers there carry out the raising of herds with the knowledge inherited from the past, without any type of standardization or at least a guide with certified norms. Due to this, the central axis of this degree work is to contribute and contribute to the development of these practices, with a technical guide based on the model of the resolution ICA68167, using the case of the farm "La Coquera", which reflects an example of the problems that continue to carry out the production of cattle raising in an empirical way.
The above was obtained through surveys, visits and study of the place, interviews with farmers, extensive research, sample calculation and other resources to establish the best way to create a guide that would benefit the farmers in their rearing process and that would also be of applicative pleasure for them, since it is complex to achieve the technical adaptation, being for this reason a gradual process and of long term results.
Thus, the use of this guide was of great support for the farmers of the "La Coquera" farm who, thanks to the training received throughout its implementation, acquired the necessary knowledge to start from a technical base and enhance their cattle raising proces
An evolutionary algorithm for the design of hybrid fiber optic-coaxial cable networks in small urban areas
Telecommunication is one of the fastest growing business sectors.
Future networks will need to integrate a wide variety of services demanding
different qualities and capacities from the network. In this paper, network
architecture based on hybrid fiber optic-coaxial cable (HFC) is proposed to
develop cable integrated telematic services. An evolutionary algorithm is
presented to solve the problem in suitable computation times when dealing with
real times civil works problems. Finally we present the results over both
problem library and real life scenarios
Evaluation of Mesoporous TiO2 Layers as Glucose Optical Sensors
[EN] Porous materials are currently the basis of many optical sensors because of their ability to provide a higher interaction between the light and the analyte, directly within the optical structure. In this study, mesoporous TiO2 layers were fabricated using a bottom-up synthesis approach in order to develop optical sensing structures. In comparison with more typical top-down fabrication strategies where the bulk constitutive material is etched in order to obtain the required porous medium, the use of a bottom-up fabrication approach potentially allows increasing the interconnectivity of the pore network, hence improving the surface and depth homogeneity of the fabricated layer and reducing production costs by synthesizing the layers on a larger scale. The sensing performance of the fabricated mesoporous TiO2 layers was assessed by means of the measurement of several glucose dilutions in water, estimating a limit of detection even below 0.15 mg/mL (15 mg/dL). All of these advantages make this platform a very promising candidate for the development of low-cost and high-performance optical sensors.This research was supported by the Spanish Ministerio de Ciencia e Innovacion (MCIN/AEI/10.13039/501100011033) through the PID2019-106965RB-C21 project, and by the European Union through the operational program of the European Regional Development Fund (FEDER) of the Valencia Regional Government 2014-2020 and of the Ministerio de Ciencia e InnovacionAgencia Estatal de Investigacion (Ref.ICTS-2017-28-UPV-9).Ortiz De Zárate-Díaz, D.; Serna, S.; Ponce-Alcántara, S.; García-Rupérez, J. (2022). Evaluation of Mesoporous TiO2 Layers as Glucose Optical Sensors. Sensors. 22(14):1-12. https://doi.org/10.3390/s22145398112221
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