1,121 research outputs found

    Density-dependent productivity in a colonial vulture at two spatial scales

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    . Understanding how density dependence modifies demographic parameters in long-lived vertebrates is a challenge for ecologists. Two alternative hypotheses have been used to explain the mechanisms behind density-dependent effects on breeding output: habitat heterogeneity and individual adjustment (also known as interference competition). A number of studies have highlighted the importance of habitat heterogeneity in density dependence in territorial species, but less information exists on demographic processes in colonial species. For these, we expect density-dependent mechanisms to operate at two spatial scales: colony and breeding unit. In this study, we used long-term data from a recovering population of Cinereous Vultures (Aegypius monachus) in southern Spain. We analyzed a long-term data set with information on 2162 breeding attempts at four colonies over a nine-year period (2002–2010) to evaluate environmental and population parameters influencing breeding output. Our results suggest that breeding productivity is subject to density-dependent processes at the colony and the nest site scale and is best explained by interference competition. Factors intrinsic to each colony, as well as environmental constraints linked to physiography and human presence, also play a role in regulatory processes. We detected the existence of a trade-off between the disadvantages of nesting too close to conspecifics and the benefits of coloniality. These could be mediated by the agonistic interactions between breeding pairs and the benefits derived from social sharing of information by breeding individuals. We propose that this trade-off may play a role in defining colony structure and may hold true for other colonial breeding bird species. Our findings also have important management implications for the conservation of this threatened species.Peer reviewe

    Fish β-parvalbumin acquires allergenic properties by amyloid assembly

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    PRINCIPLES: Amyloids are highly cross-β-sheet-rich aggregated states that confer protease resistance, membrane activity and multivalence properties to proteins, all essential features for the undesired preservation of food proteins transiting the gastrointestinal tract and causing type I allergy. METHODS: Amyloid propensity of β-parvalbumin, the major fish allergen, was theoretically analysed and assayed under gastrointestinal-relevant conditions using the binding of thioflavin T, the formation of sodium dodecyl sulphate- (SDS-) resistant aggregates, circular dichroism spectroscopy and atomic force microscopy fibril imaging. Impact of amyloid aggregates on allergenicity was assessed with dot blot. RESULTS: Sequences of β-parvalbumin from species with commercial value contain several adhesive hexapeptides capable of driving amyloid formation. Using Atlantic cod β-parvalbumin (rGad m 1) displaying high IgE cross-reactivity, we found that formation of amyloid fibres under simulated gastrointestinal conditions accounts for the resistance to acid and neutral proteases, for the presence of membrane active species under gastrointestinal relevant conditions and for the IgE-recognition in the sera of allergic patients. Incorporation of the anti-amyloid compound epigallocatechin gallate prevents rGad m 1 fibrillation, facilitates its protease digestion and impairs its recognition by IgE. CONCLUSIONS: the formation of amyloid by rGad m 1 explains its degradation resistance, its facilitated passage across the intestinal epithelial barrier and its epitope architecture as allergen.Peer Reviewe

    High radon levels in subterranean environments: monitoring and technical criteria to ensure human safety (case of Castañar cave, Spain)

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    Castañar cave contains the highest radon gas (222Rn) concentration in Spain with an annual average of 31.9 kBq m−3. Seasonal variations with summer minimums and maximum values in fall were recorded. The reduction of air-filled porosity of soil and rock by condensation or rainfalls hides the radon exchange by gas diffusion, determining this seasonal stair-step pattern of the radon activity concentration in underground air. The effective total dose and the maximum hours permitted have been evaluated for the guides and public safety with a highly detailed radon measurement along 2011 and 2012. A network of 12 passive detectors (kodalphas) has been installed, as well as, two radon continuous monitoring in the most interesting geological sites of the subterranean environment.A follow up of the recommended time (max. 50 min) inside the underground environment has been analysed since the reopen to public visitors for not surpassing the legal maximum effective dose for tourists and guides. Results shown that public visitors would receive in fall a 12.1% of the total effective dose permitted per visit, whereas in summer it is reduced to 8.6%, while the cave guide received a total effective dose of 6.41 mSv in four months.The spatial radon maps allow defining the most suitable touristic paths according to the radon concentration distribution and therefore, appropriate fall and summer touristic paths are recommended.This research was funded by the Regional Government of Extremadura (Spain) through EAFRD Axis 2 “Improving the environment and the countryside” and the Spanish Ministry of Economy and Competitiveness through project CGL2013-43324R and the programme Torres Quevedo (PTQ 13-06296 and PTQ 12-05601).A.F-C is funded by an IEF Marie Curie Action (FP7/2007–2013) under REA grant agreement n° 624204Peer reviewe

    Design and psychometric evaluation of the 'Clinical Communication Self-Efficacy Toolkit'

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    Nursing students experience difficulties when communicating in clinical practice. Their self-efficacy in clinical communication should be explored as part of their competence assessment before they are exposed to real human interactions in the clinical setting. The aim of this study was to design and psychometrically evaluate a toolkit to comprehensively assess nursing students’ self-efficacy in clinical communication. The study followed an observational cross-sectional design. A sample of 365 nursing students participated in the study. The ‘Clinical Communication Self-Efficacy Toolkit’ (CC-SET) was comprised of three tools: the ‘Patient-Centered Communication Self-efficacy Scale’ (PCC-SES), the ‘Patient clinical Information Exchange and interprofessional communication Self-Efficacy Scale’ (PIE-SES), and the ‘Intrapersonal communication and Self-Reflection Self-Efficacy Scale’ (ISR-SES). The tools’ reliability, validity (content, criterion, and construct) and usability were rigorously tested. The Cronbach’s alpha coefficient of the three tools comprising the CC-SET was very high and demonstrated their excellent reliability (PCC-SES = 0.93; PIE-SES = 0.87; ISR-SES = 0.86). The three tools evidenced to have excellent content validity (scales’ content validity index > 0.95) and very good criterion validity. Construct validity analysis demonstrated that the PCC-SES, PIE-SES, and ISR-SES have a clear and theoretically-congruent structure. The CC-SET is a comprehensive toolkit that allows the assessment of nursing students’ self-efficacy in interpersonal, interprofessional, and intrapersonal communication

    Marginal bone loss around implants placed in maxillary native bone or grafted sinuses: a retrospective cohort study

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    Objectives To assess differences in marginal bone loss around implants placed in maxillary pristine bone and implants placed following maxillary sinus augmentation over a period of 3 years after functional loading. Material and methods Two cohorts of subjects (Group 1: Subjects who received sinus augmentation with simultaneous implant placement; Group 2: Subjects who underwent conventional implant placement in posterior maxillary pristine bone) were included in this retrospective study. Radiographic marginal bone loss was measured around one implant per patient on digitized panoramic radiographs that were obtained at the time of prosthesis delivery (baseline) and 12, 24, and 36 months later. The influence of age, gender, smoking habits, history of periodontal disease, and type of prosthetic connection (internal or external) on marginal bone loss was analyzed in function of the type of osseous support (previously grafted or pristine). Results A total of 105 subjects were included in this study. Cumulative radiographic marginal bone loss ranged from 0 mm to 3.9 mm after 36 months of functional loading. There were statistically significant differences in marginal bone loss between implants placed in grafted and pristine bone at the 12‐month assessment, but not in the subsequent progression rate. External prosthetic connection, smoking, and history of periodontitis negatively influenced peri‐implant bone maintenance, regardless of the type of osseous substrate. Conclusions Implants placed in sites that received maxillary sinus augmentation exhibited more marginal bone loss than implants placed in pristine bone, although marginal bone loss mainly occurred during the first 12 months after functional loading. Implants with external implant connection were strongly associated with increased marginal bone loss overtime.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/102685/1/clr12122.pd

    Development and Initial testing of a Virtual Laboratory for the Build-up and Testing of Microgrid Management Algorithms

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    In a bid of facilitating the increasing penetration of intermittent and random renewable energies, microgrids along with their management algorithms are becoming crucial assets. To prove their effectiveness, these algorithms need to be tested in real environments and/or laboratories, which can be very difficult in many cases, especially at the initial development stages. To solve this issue, this article proposes the use of a laboratory digital twin, i.e., a virtual laboratory with a behaviour that is similar to that of real installations, aimed at facilitating the development, testing and debugging of microgrids management algorithms. The proposed solution is demonstrated to be safe and complete when it comes to test these algorithms.Acknowledgement This publication is part of the Sistemas energéticos aislados 100% renovables ENERISLA (exp. CER-20191002) Project which has received a grant from the Centre for Industrial Technological Development (CDTI, Centro para el Desarrollo Tecnológico Industrial in Spanish) under the Ministry of Science and Innovation in the call Acreditación y Concesión de Ayudas destinadas a Centros Tecnológicos de Excelencia “Cervera” in 2019. This research has received funding from the European Union’s Horizon 2020 Framework Program for Research and Innovation under grant agreement no. 893857

    Update of scientific observations of white marlin (kajikia albida) in the spanish surface longline fishing fleet targeting swordfish in the Atlantic in the period 1993-2018

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    A description of 1710 individuals recorded as white marlin during the period 1993-2018 is presented. 21% of the fishing sets were positive for the capture of at least one specimen for those areas considered. The overall prevalence of this species over all fish species combined was 0.65% in number and 0.52% in weight. The overall prevalence over Istiophoridae was 25.12% and 12.61% in number and weight, respectively. A discussion on the applicability of these values is included. Sizes were between 95 and 285 cm LJFL but catches of individuals smaller than 145 cm are very rare. The overall sex-ratio of females was 42.5%. Sex-ratio at size indicates an increase in the percentage of females in sizes larger than 165 cm. Only 7 females of the total 170 females with gonads analyzed presented a high gonadosomatic index. Overall nominal CPUE in weight was higher for males (2.70 kg DW/1000 hooks) than females (1.81 kg DW/1000 hooks). For the whole period analyzed, 16.3% of the specimens observed were discarded and 7.5% were released alive, although different patterns can be discerned over time

    Psychometric evaluation and cultural adaptation of the Spanish version of the “Scale for End-of Life Caregiving Appraisal”

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    Objective: To translate, culturally adapt and psychometrically evaluate the Spanish version of the ‘Scale for End-of Life Caregiving Appraisal’ (SEOLCAS). Methods: Observational cross-sectional study. Convenience sample of 201 informal end-of-life caregivers recruited in a southern Spanish hospital. The reliability of the questionnaire was assessed through its internal consistency (Cronbach’s α) and temporal stability (Pearson’s correlation coefficient (r) between test-retest). The content validity index of the items (I-CVI) and the scale (S-CVI/Ave) was calculated. Its criterion validity was explored through performing a linear regression analysis to evaluate the SEOLCAS’ predictive validity. Exploratory factor analysis was used to examine its construct validity. Results: The SEOLCAS’s reliability was very high (Cronbach’s α=0.92). Its content validity was excellent (all items’ content validity index=0.8–1; scale’s validity index=0.88). Evidence of the SEOLCAS’ criterion validity showed that the participants’ scores on the SEOLCAS explained approximately 79.3% of the between-subject variation of their results on the Zarit Burden Interview. Exploratory factor analysis provided evidence of the SEOLCAS’ construct validity. This analysis revealed that two factors (‘internal contingencies’ and ‘external contingencies’) explained 53.77% of the total variance found and reflected the stoic Hispanic attitude towards adversity. Significance of the results: The Spanish version of the ‘Scale for End-of Life Caregiving Appraisal’ has shown to be an easily-applicable, valid, reliable and culturally-appropriate tool to measure the impact of end-of-life care provision on Hispanic informal caregivers. This tool offers healthcare professionals the opportunity to easily explore Hispanic informal end-of-life caregivers’ experiences and discover the type of support they may need (instrumental or emotional) even when there are communicational and organisational constraints
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