2,866 research outputs found
Leveraging limited data from wildlife monitoring in a conflict affected region in Venezuela
Efficient monitoring of biodiversity-rich areas in conflict-affected areas with poor rule of law requires a combination of different analytical approaches to account for data biases and incompleteness. In the upland Amazon region of Venezuela, in Canaima National Park, we initiated biodiversity monitoring in 2015, but it was interrupted by the establishment of a large-scale mining development plan in 2016, compromising the temporal and geographical extent of monitoring and the security of researchers. We used a resource selection function model framework that considers imperfect detectability and supplemented detections from camera trap surveys with opportunistic off-camera records (including animal tracks and direct sighting) to (1) gain insight into the value of additional occurrence records to accurately predict wildlife resource use in the perturbated area (deforestation, fire, swidden agriculture, and human settlements vicinity), (2) when faced with security and budget constraints. Our approach maximized the use of available data and accounted for biases and data gaps. Adding data from poorly sampled areas had mixed results on estimates of resource use for restricted species, but improved predictions for widespread species. If budget or resources are limited, we recommend focusing on one location with both on-camera and off-camera records over two with cameras. Combining camera trap records with other field observations (28 mammals and 16 birds) allowed us to understand responses of 17 species to deforestation, 15 to fire, and 13 to swidden agriculture. Our study encourages the use of combinations of methods to support conservation in high-biodiversity sites, where access is restricted, researchers are vulnerable, and unequal sampling efforts exist
Influence of postweaning feeding management of beef heifers on performance and physiological profiles through rearing and first lactation
The aim of this study was to examine the effects of 2 postweaning feeding management approaches (FEED: 0.8 [HIGH] vs 0.6 [MOD] kg/d target ADG) on the performance of heifers of 2 beef breeds (BREED: Parda de Montaña [PA] vs Pirenaica) calving at 2 yr. Twenty-five heifers previously creep fed before weaning (6 mo) were assigned to 2 planes of nutrition from 6 to 15 mo of age. At 15 mo, they were inseminated, and then received similar diets until weaning of their first calf (4 mo postcalving). Several parameters were measured to analyze growth and development (BW; ADG; size measures at 6 mo, 15 mo, calving, and weaning), performance at puberty and first breeding, and dam and calf performance in the first lactation (calving traits, ADG, milk yield). Metabolic (glucose, cholesterol, NEFA, ß-hydroxybutyrate, and urea) and endocrine status (IGF-I and leptin) were assessed in plasma samples collected every 3 mo from 6 mo to calving and monthly during lactation. No interaction between BREED and FEED was observed. Heifers from the HIGH feeding treatment had higher postweaning ADG than those on the LOW diet. At 15 mo, they had greater BW, heart girth, and external pelvic area, but they did not differ thereafter. All heifers reached puberty at similar BW (55% mature BW) but different ages. Heifers from the HIGH treatment tended (P < 0.09) to be pubertal earlier, and PA heifers were 1.6 mo younger than Pirenaica heifers (P < 0.05) at puberty. At the time of conception (452 ± 59 kg) and calving (471 ± 51 kg), BW was above common recommendations in all groups. Calving traits and performance in lactation did not differ between feeding treatments. BREED only influenced birth weight; PA calves being heavier (P < 0.05), which resulted in a larger calf/cow BW ratio, but no effect on calving difficulty or subsequent performance. Metabolic substrates and hormones depended mostly on sampling date, which was related to current energy and protein intake. Glucose (P < 0.001), cholesterol (P < 0.001), and IGF-I (P < 0.05) were greater during the postweaning phase in heifers on the HIGH diet, and persistent physiological effects were observed during lactation. Age at puberty was negatively related with IGF-I (r = -0.43, P < 0.001), but not with leptin concentrations. In conclusion, regardless of breed, a moderate growth rate ensured adequate heifer development and performance until the first lactation, whereas no advantage was gained from enhanced postweaning gains
Evolution of grape polyphenol oxidase activity and phenolic content during maturation and vinification
The activity of polyphenol oxidase (PPO) and content of phenolic compounds were followed during the maturation in two varieties of wine grapes grown in south-eastern Spain and during vinification at different sulphur dioxide concentrations.Both cresolase and catecholase activities (measured at pH 7.0 and 4.5, respectively) increased throughout the studied period and the content of phenolic compounds decreased rapidly when expressed as concentration (mg gallic acid/g total fresh weight), while when expressed as total amount per berry (mg/berry) it remained constant. During wine production, the enzyme activity was highest immediately after crushing of the fresh grapes and was not detected at the end of the fermentation process. The phenolic content also decreased during vinification to a constant level depending on the S02 level used
Effects of compost stability and contaminant concentration on the bioremediation of PAHs contaminated soil through composting
The objective of this study was to investigate the effect of two factors: the stability degree (0.37-4.55 mg O₂ g⁻¹ Organic Matter h⁻¹) of different composts derived from the organic fraction of municipal solid wastes and the concentration of a complex mixture of PAHs including flourene, phenanthrene, anthracene, flouranthene, pyrene and benzo(a)anthracene in the bioremediation of soil. The two factors were systematically studied applying central composite design methodology. The obtained results demonstrated that compost stability degree was particularly important during the first stage of the process. Stable composts enhanced the levels of degradation in soil-compost mixture and a degradation rate of 92% was achieved in this period, but only 40% was degraded with the least stable compost. The PAHs concentration was also important during the process, since the degradation rates increased with the increase in the PAHs concentration. Moreover, all the individual PAHs demonstrated a notable decrease in their concentrations after the incubation period, but pyrene was degraded to lower levels in some treatments compared to others PAHs
Reputation drives cooperative behaviour and network formation in human groups
Cooperativeness is a defining feature of human nature. Theoreticians have suggested several mechanisms to explain this ubiquitous phenomenon, including reciprocity, reputation, and punishment, but the problem is still unsolved. Here we show, through experiments conducted with groups of people playing an iterated Prisoner's Dilemma on a dynamic network, that it is reputation what really fosters cooperation. While this mechanism has already been observed in unstructured populations, we find that it acts equally when interactions are given by a network that players can reconfigure dynamically. Furthermore, our observations reveal that memory also drives the network formation process, and cooperators assort more, with longer link lifetimes, the longer the past actions record. Our analysis demonstrates, for the first time, that reputation can be very well quantified as a weighted mean of the fractions of past cooperative acts and the last action performed. This finding has potential applications in collaborative systems and e-commerce.This work was supported in part by MINECO (Spain) through grants PRODIEVO, FIS2011-25167, and FIS2009-09689, by Comunidad de Madrid (Spain)
through grant MODELICO-CM, by Comunidad de Aragón (Spain) through a grant to the group FENOL, and by the EU FET Proactive project MULTIPLEX (contract no. 317532)
Correlation between impact factor and public availability of published research data in information science & library science journals
Trabajo presentado a la 15th International Society of Scientometrics and Informetrics Conference, celebrada en Estambúl (Turquia) del 29 de junio al 4 de julio de 2015.Scientists continuously generate research data but only a few part of them are published. If these data were accessible and reusable, researchers could examine them and generate new knowledge. Currently, the barriers to data sharing are phased
out and public research organizations are demanding ever more insistently that publications resulting from publicly funded projects and data that support them should be published in open (Savage & Vickers, 2009). The purpose of this work is: a) to analyse policies concerning open availability of raw research data in journals in the
Information Science & Library Science (ISLS); and b) to determine whether there is a correlation between the impact factor and policies of these journals concerning storage and reuse of scientific data.This work has benefited from assistance by the National R+D+I of the Ministry of Economy and Competitiveness of the Spanish Government (CSO2012-39632-C02-01) and Prometeo Program for excellent research groups of Generalitat
Valenciana (GVPROMETEO2013-041).Peer Reviewe
Anaerobic degradation of PAHs in soil : impacts of concentration and amendment stability on the PAHs degradation and biogas production
In this study, the bioremediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soil under strict anaerobic-methanogenic conditions was systematically studied applying the central composite design approach. The effect of PAHs concentration and the stability of the compost as an organic amendment for anaerobic digestion were examined. In all assays, the used methanogenic consortium was able to degrade the PAHs although some inhibition effects were observed during the initial stage in some cases. The degradation rates varied between 31.4 and 90.6% during 50 days incubation period. The study demonstrated that the PAHs concentration influences the degradation rate where more degradation was observed by increasing the concentration of PAHs. However, the biogas production as a result of the digestion process was more influenced by the compost stability which also has its effect on the degradation rates as more degradation occurred with more stable compost, but more biogas was produced with less stable compost, which indicates that the biogas is mainly produced by the anaerobic digestion of the amended compost. Finally, it seems that compost addition is required to improve the process in some cases but in other circumstances it does not greatly improve the bioremediation of PAHs
Influence of vegetable oil sources on quality parameters of broiler meat
The use of different vegetable oils in animal nutrition has allowed the producer to obtain highly energetic diets at very low costs, while offering an optimum and well-appreciated product to the consumer. Nowadays, numerous efforts are taken to enrich poultry meat with polyunsaturated fatty acids (PUFA) and, especially, with omega-3 fatty acids, because of the proven benefits on human health (Kinsella et al., 1990; Knapp, 1991). But, up to now there have not been done complementary studies dealing with the influence of such nutritive improvements on the different technological characteristics of poultry meat. Besides this, there also exist few experiments dealing with the influence of the enrichment with PUFA on the subjective parameters of organoleptic quality. Those experiments are usually more related to the use of fish ingredients in animal diets. The aim of the present experiment was to study the effects of different vegetable oils (rapeseed, soybean, sunflower and linseed) on the technical, nutritive and organoleptic quality of chicken meat, and on the profiles of essential fatty acids (EFA) in the cloacal fat and in the tissues
Self-defined information indices: application to the case of university rankings
University rankings are now relevant decision-making tools for both institutional and private purposes in the management of higher education and research.
However, they are often computed only for a small set of institutions using some
sophisticated parameters. In this paper we present a new and simple algorithm to calculate an approximation of these indices using some standard bibliometric variables,
such as the number of citations from the scientific output of universities and the number of articles per quartile. To show our technique, some results for the ARWU index
are presented. From a technical point of view, our technique, which follows a standard
machine learning scheme, is based on the interpolation of two classical extrapolation
formulas for Lipschitz functions defined in metric spaces—the so-called McShane
and Whitney formulae—. In the model, the elements of the metric space are the universities, the distances are measured using some data that can be extracted from the
Incites database, and the Lipschitz function is the ARWU index
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