3,036 research outputs found

    Estimating recruitment and survival in partially monitored populations

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    In evolutionary and ecological studies, demographic parameters are commonly derived from detailed information collected on a limited number of individuals or in a confined sector of the breeding area. This partial monitoring is expected to underestimate survival and recruitment processes because individuals marked in a monitored location may move to or recruit in an unobservable site. We formulate a multi-event capture-recapture model using E-SURGE software which incorporates additional information on breeding dispersal and the proportion of monitored sites to obtain unbiased estimates of survival and recruitment rates. Using simulated data, we assessed the biases in recruitment, survival and population growth rate when monitoring 10-90% of the whole population in a short- and a long-lived species with low breeding dispersal. Finally, we illustrate the approach using real data from a long-term monitoring program of a colony of Scopoli's shearwaters Calonectris diomedea. We found that demographic parameters estimated without considering the proportion of the area monitored were generally underestimated. These biases caused a substantial error in the estimated population growth rate, especially when a low proportion of breeding individuals were monitored. The proposed capture-recapture model successfully corrected for partial monitoring and provided robust demographic estimates. Synthesis and applications. In many cases, animal breeding populations can only be monitored partially. Consequently, recruitment and immature survival are underestimated, but the extent of these biases depends on the proportion of the area that remains undetected and the degree of breeding dispersal. We present a new method to obtain robust and unbiased measures of survival and recruitment processes from capture-recapture data. The method can be applied to any monitored population regardless of the type of nests (e.g. artificial or natural) or breeding system (e.g. colonial or territorial animals), and it only relies on an estimate of the proportion of the monitored area. The unbiased estimates obtained by this method can be used to improve the reliability of predictions of demographic population models for species' conservation and management.Research funds were provided by the Spanish Ministries of Science, Economy and Competitiveness (refs. BOS2003-01960, CGL2006-04325/BOS, CGL2009-08298, CGL2013-42203-R, JCI-2011-09085)Peer Reviewe

    1,3-Dien-5-ynes: Versatile Building Blocks for the Synthesis of Carbo- and Heterocycles

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    1,3-Dien-5-ynes have been extensively used as starting materials for the synthesis of a wide number of different carbo- and heterocycles. The aim of this review is to give an overview of their utility in organic synthesis, highlighting the variety of compounds that can be directly accessed from single reactions over these systems. Thus, cycloaromatization processes are initially commented, followed by reactions directed toward the syntheses of five-membered rings, other carbocycles and, finally, heterocycles. The diverse methodologies that have been developed for the synthesis of each of these types of compounds from 1,3-dien-5-ynes are presented, emphasizing the influence of the reaction conditions and the use of additional reagents in the outcome of the transformations.Ministerio de Economía y Competitividad (MINECO) and FEDER (CTQ2013-41336-P, CTQ2013- 48937-C2-1-P, and CTQ2014-52488-R), Universidad de Alcalá (CCG2015/EXP-003) and Junta de Castilla y León (BU237U13

    Knowledge, Attitudes, Risk Perceptions, and Practices of Spanish Adolescents Toward the COVID-19 Pandemic: Validation and Results of the Spanish Version of the Questionnaire

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    Background: Adolescence is a period with physical, psychological, biological, intellectual, and social changes in which there is usually little perception of risk. COVID-19 has generated constant situations of change and uncertainty worldwide. During the pandemic, the acquisition of preventive behaviors has been relevant. Various studies carried out with adults associate risk perception and the implementation of preventive behaviors with knowledge about the COVID-19 and with age, but there are not many studies with adolescents. Therefore, the objective is to validate, in Spanish, the questionnaire of the knowledge, attitudes, risk perceptions, and practices of adolescents toward the pandemic, and analyze it according to sociodemographic characteristics.Method: This study was a descriptive cross-sectional study, which included adolescents between the ages of 12-18 (n = 354). First, a translation and a back-translation of the questionnaire were performed. The questionnaire was presented in several high schools chosen by convenience sampling and following a non-probabilistic snowball sampling. Reliability and validity analyses were then carried out and the relationships between the different sociodemographic variables (gender, place of residence, level of education, if the person was in a sentimental relationship, and financial aid) were analyzed.Results: The reliability of the questionnaire is acceptable (ordinal alpha = 77%). Knowledge was higher in women, and in those with a higher level of education; and were lower in those who lived in smaller towns, as well as in those who had a member of their family receiving financial aid. In terms of attitudes and risk perceptions, younger adolescents had higher scores, and those who had a member of their family receiving financial aid, lower.Conclusion: The questionnaire is a reliable tool in the Spanish adolescent population. Knowledge was influenced by gender, place of residence, level of education, and financial aid. Attitudes and risk perceptions were influenced by age and financial aid. For practices, no predictors were found. In general, adolescents scored lower on knowledge about COVID-19, but they scored higher on COVID-19 safety practices

    Poultices Generated Mechanically with Compressed Air: “Gunpoint Mix System” Characterization and Properties. Comparison with “Handmade” Poultices

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    The authors have developed an automated method Gunpoint mix hQps youtu be 4uXC_OoP7EM for the manufacture of poultrices The proper es of the cellulose poultrices placed manually with those placed with the GunPoint Mix method applied on stone substrates of known characteris cs are compared Arbocel BWW40 is used in both cases The physical parameters of the cellulose the microscopic texture the absorp on and desorp on proper es the penetra on of a consolida ng product and the ease of cleaning are measured The main advantage of the Gunpoint mix method lies in the speed of the applica on that allows a very exact control of the applica on mes Given its good adhesion it can be applied with the same speed in the roof and top of the vaults upside down without the risk of landslides The water parameters of each type of poultrice provide informa on to the restorer to decide on what type of treatment is more appropriate to use a handmade poultrice or a Gunpoint mix poultric

    Microbial weathering of Fe-rich phyllosilicates and formation of pyrite in the dolomite precipitating environment of a Miocene lacustrine system

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    Sedimentary sequences composed of selenite gypsum, mudstone, and dolomite microbialites cropping out in the eastern part of the Madrid Basin were deposited in a mudflat – saline-lake system during the Miocene. In some dolomite beds enriched in detrital grains, dolomite crystals occur intergrown with framboidal pyrite clusters that in many cases are arranged along the associated phyllosilicate cleavages, which accounts for the mineral disaggregation, and eventually for the mineral replacement. Highresolution FE-SEM investigations across the interface between the pyrite and the phyllosilicate show that a single phyllosilicate is replaced by iron sulphides in different microsites, with retention of some aspects of the parent structure. Pyrite formed in the sediment as texturally complex framboids, coexisting with amorphous to poorly crystalline iron-rich sulphide phases, and include carbonaceous filaments with biogenic isotopic signatures (δ 13 C = -22.95 ‰). Microprobe analytical data indicate the weathered phyllosilicates to be significantly depleted in Fe relative to Si and Al. The selective release of Fe has not involved the mineral transformation to secondary phyllosilicates, which suggests a preferential microbial colonization of the Fe-bearing minerals rather than a thermodynamically driven degradation of those minerals. Depleted δ 34 S values in pyrite further suggest that sulphate microbial reduction to sulphide was active within the sediment during the alteration of the silicates. This paper gives new insight into the microbial weathering of phyllosilicates and the subsequent formation of pyrite through a sequence of intermediate products enriched in iron. These processes were coeval with the microbially-mediated precipitation of dolomite, which further reinforces the role of the microbes in the formation of the sulphides

    Multi-event capture-recapture analysis reveals individual foraging specialization in a generalist species

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    © 2015 by the Ecological Society of America. Populations of species typically considered trophic generalists may include specialized individuals consistently feeding on certain resources. Optimal foraging theory states that individuals should feed on those resources most valuable to them. This, however, may vary according to individual differences in detecting or processing resources, different optimization criteria, and competitive abilities. White Storks (Ciconia ciconia) are trophic generalists at the population level. Their European population recovery has been attributed to increased wintering in southern Europe (rather than Africa) where they feed upon new anthropogenic food subsidies: predictable dumps and less predictable and more difficult to detect, but abundant, invasive Procambarus clarkii crayfishes in ricefields. We studied the foraging strategies of resident and wintering storks in southwestern Spain in ricefields and dumps, predicting that more experience in the study area (residents vs. immigrants, old vs. young) would increase ricefield specialization. We developed the first multi-event capture- recapture model to evaluate behavioral consistency, analyzing 3042 observations of 1684 banded storks. There were more specialists among residents (72%) than immigrants (40%). All resident specialists foraged in ricefields, and ricefield use increased with individual age. In contrast, some immigrants specialized on either dumps (24%) or ricefields (16%), but the majority were generalists (60%). Our results provide empirical evidence of high individual foraging consistency within a generalist species and a differential resource selection by individuals of different ages and origins, probably related to their previous experience in the foraging area. Thus, future changes in food resource availability at either of the two anthropogenic subsidies (ricefields or dumps) may differentially impact individuals of different ages and origins making up the wintering population. The use of multi-event capture- recapture modeling has proven useful for studying interindividual variability in behavior.Peer Reviewe

    Can Establishment Success Be Determined through Demographic Parameters? A Case Study on Five Introduced Bird Species

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    The dominant criterion to determine when an introduced species is established relies on the maintenance of a self-sustaining population in the area of introduction, i.e. on the viability of the population from a demographic perspective. There is however a paucity of demographic studies on introduced species, and establishment success is thus generally determined by expert opinion without undertaking population viability analyses (PVAs). By means of an intensive five year capture-recapture monitoring program (involving \u3e12,000 marked individuals) we studied the demography of five introduced passerine bird species in southern Spain which are established and have undergone a fast expansion over the last decades. We obtained useful estimates of demographic parameters (survival and reproduction) for one colonial species (Ploceus melanocephalus), confirming the long-term viability of its local population through PVAs. However, extremely low recapture rates prevented the estimation of survival parameters and population growth rates for widely distributed species with low local densities (Estrilda troglodytes and Amandava amandava) but also for highly abundant yet non-colonial species (Estrilda astrild and Euplectes afer). Therefore, determining the establishment success of introduced passerine species by demographic criteria alone may often be troublesome even when devoting much effort to field-work. Alternative quantitative methodologies such as the analysis of spatio-temporal species distributions complemented with expert opinion deserve thus their role in the assessment of establishment success of introduced species when estimates of demographic parameters are difficult to obtain, as is generally the case for non-colonial, highly mobile passerines

    El problema de la dualidad entre las producciones culturales y su contexto: una propuesta didáctica patrimonial

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    Este Trabajo Fin de Máster surge de una dificultad didáctica en Historia, la dualidad entre las producciones culturales y su contexto. Este problema socaba el objetivo número 7, establecido en el Currículo Oficial de Aragón. Ha sido detectado durante el transcurso del Practicum II, avalado por el tutor del centro, así como por bibliografía. Los alumnos son capaces de comprender con cierta profundidad las producciones culturales, pero tienen una gran dificultad a la hora de relacionarlas con su contexto, por lo que acaban quedándose en cuestiones formales. Por lo tanto, se propone un planteamiento que desde una didáctica patrimonial consiga ofrecer una visión de conjunto. Para ello se ha desglosado el contexto, en las facetas (histórico, social, económico...) más adecuadas para la Edad Media. En cada actividad a través de un ejemplo patrimonial diferente, se trabaja un tipo de contexto específico. El conjunto de actividades a su término pretende ofrecer a los alumnos toda una panorámica de lo que supone el contexto de las producciones culturales. Para ello se han usado diferentes metodologías, agrupamientos y fuentes, aunque remitiendo todos ellos a un planteamiento didáctico común.<br /
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