103 research outputs found

    Big fish eat small fish: implications for food chain length?

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    Food chains in the pelagic zones of oceans and lakes are longer than in terrestrial ecosystems. The perception of the pelagic food web has become increasingly complex by progressing from a linear food chain (phytoplankton – crustacean zooplankton – planktivorous fish – predatory fish) to a food web because of an increasing appreciation of microbial trophic pathways, side-tracks by gelatinous zooplankton and a high prevalence of omnivory. The range of predator:prey size ratios by far exceeds the traditionally assumed range of 10:1 to 100:1, from almost equal length to 105:1. The size ratios between primary consumers and top predators are 3½ orders of magnitude bigger in pelagic than in terrestrial food webs. Comparisons between different pelagic ecosystems support ecosystem size as an important factor regulating the maximal trophic level, while energy limitation of the number of trophic levels is less well supported. An almost 1:1 relationship between ingestion by predators and prey mortality and a better chemical match between primary producer and herbivore biomass are further distinctive features of the pelagic food web whose role in explaining the higher number of trophic levels in pelagic systems needs further examination

    Massive fish mortality in Ismarida Lake, Greece: identification of drivers contributing to the fish kill event

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    During the end of August 2013, a massive fish mortality occurred in Ismarida Lake, a small and shallow system of Northern Greece, where approximately 10-18 tons of euryhaline fish died. This study attempts to describe the event of this fish kill or Massive Fish Mortality (MFM) that occurred in Ismarida Lake during the night of August 28, 2013, and to identify the possible drivers that may have triggered this event. A combined hydrographic, ichthyological and phytoplankton survey were carried out along with a toxicological analysis. Finally, the study proposes both short-term and long-term measures for the management of both quality and quantity of the water (ground and surface) resources in the broader basin of Ismarida Lake

    Developing a heritage BIM shared library for two case studies in Jordan’s heritage: The House of Art in Amman and the Qaqish House in the World Heritage City of As-Salt

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    International research is moving towards the development of BIM (Building Information Modelling) libraries applied to the built heritage where one of the main issues to be addressed is the modelling of complex or unique shapes that represent the specific construction components of every single asset. This perspective addresses the generation of parametric families of representative architectural geometry in the context of the management and representation of a building of heritage value. Jordan’s architectural heritage has gone through a long period of evolution and development: the result is a mixture of influences and traditions, making a great stride to conserve its buildings and Historical Heritage but has never adopted advanced digital technologies such as Building Information Modelling. In this framework, the present research aims to bridge the gap in Jordan by applying digital technologies to support heritage conservation plans by creating a 3D library of BIM objects related to typical elements of Jordanian and Arabic architecture, specifically in two cases of study. Co-production and collaboration with diverse stakeholders were central to the development of the methodology and design of the research.As a result, the first open-access HBIM shared library of historical features of Jordanian built heritage will be consolidated; this is crucial because it will set a precedent for the further documentation and conservation of the heritage of traditional cities in Jordan, MENA countries and internationally by promoting social cohesion, economic and technological development, tourism and the awareness of Jordan’s cultural heritage

    Nurses' workload and its relation with physiological stress reactions

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    OBJECTIVE: to analyze the relation between the workload and the physiological stress reactions among nurses working at a hospital service. METHODS: cross-sectional, correlational, quantitative study, involving 95 nurses, in 2011 and 2012. Spearman's bivariate Correlation Test was used. RESULTS: most subjects are female, between 23 and 61 years old and working between 21 and 78 hours per week. The most frequent physiological reactions were back pain, fatigue/exhaustion, stiff neck and stomach acidity, with 46.3% of the subjects presenting low and 42.1% moderate physiological stress responses. No correlation was found between the workload and the physiological stress responses. CONCLUSION: although most of the nurses work more than 36 hours/week, physiologically, they do not present high reaction levels in response to stress. These workers deal with conflicts in the vertical and horizontal relations between professionals, family members and patients. In that sense, taking care of professionals who offer health services can be a fundamental strategy, as good user care mainly depends on healthy teams.OBJETIVO: analisar a relação entre a carga horária de trabalho e as reações fisiológicas do estresse, entre enfermeiros de unidade hospitalar. MÉTODOS: estudo transversal, correlacional, quantitativo, realizado com 95 enfermeiros em 2011 e 2012. De forma bivariada, utilizou-se o teste de correlação de Spearman. RESULTADOS: a maioria dos sujeitos pertencia ao sexo feminino, faixa etária entre 23 e 61 anos, trabalhando de 21 a 78 horas semanais. As reações fisiológicas mais frequentes foram dores lombares, fadiga/exaustão, rigidez no pescoço e acidez estomacal, sendo que 46,3% dos sujeitos apresentaram baixas respostas fisiológicas ao estresse e moderadas em 42,1%. Não houve correlação entre a carga horária de trabalho e as reações fisiológicas do estresse. CONCLUSÃO: embora a maioria dos enfermeiros exercesse suas funções por mais de 36 horas/semana, fisiologicamente não apresentavam reações elevadas de resposta ao estresse. Tais trabalhadores lidavam com conflitos nas relações verticais e horizontais entre profissionais, familiares e pacientes. Nesse sentido, cuidar de profissionais que oferecem serviços de saúde pode ser estratégia fundamental, uma vez que bons atendimentos aos usuários dependem, principalmente, de equipes saudáveis.OBJETIVO: analizar la relación entre la carga horaria de trabajo y las reacciones fisiológicas de estrés entre enfermeros de servicio hospitalario. MÉTODOS: estudio trasversal, correlacional, cuantitativo, desarrollado con 95 enfermeros en 2011 y 2012. De forma bivariada, fue utilizada la Prueba de Correlación de Spearman. RESULTADOS: la mayoría de los sujetos es del sexo femenino, rango de edad entre 23 y 61 años y trabaja de 21 a 78 horas semanales. Las reacciones fisiológicas más frecuentes fueron dolores de espalda, fatiga/agotamiento, rigidez en el cuello y acidez estomacal, siendo que 46,3% de los sujetos revelaron bajas respuestas fisiológicas al estrés y moderadas en 42,1%. No fue encontrada correlación entre la carga horaria de trabajo y las reacciones fisiológicas del estrés. CONCLUSIÓN: aunque la mayoría de los enfermeros ejerza su función por más de 36 horas/semana, fisiológicamente no muestran reacciones elevadas de respuesta al estrés. Tales trabajadores lidian con conflictos en las reacciones verticales y horizontales entre profesionales, familiares y pacientes. En ese sentido, cuidar de profesionales que ofrecen servicios de salud puede ser estrategia fundamental, ya que buena atención a los usuarios depende principalmente de equipos saludables

    Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

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    BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

    A Daily Diary Approach to the Examination of Chronic Stress, Daily Hassles and Safety Perceptions in Hospital Nursing

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    Purpose: Stress is a significant concern for individuals and organisations. Few studies have explored stress, burnout and patient safety in hospital nursing on a daily basis at the individual level. This study aimed to examine the effects of chronic stress and daily hassles on safety perceptions, the effect of chronic stress on daily hassles experienced and chronic stress as a potential moderator. Method: Utilising a daily diary design, 83 UK hospital nurses completed three end-of-shift diaries, yielding 324 person days. Hassles, safety perceptions and workplace cognitive failure were measured daily, and a baseline questionnaire included a measure of chronic stress. Hierarchical multivariate linear modelling was used to analyse the data. Results: Higher chronic stress was associated with more daily hassles, poorer perceptions of safety and being less able to practise safely, but not more workplace cognitive failure. Reporting more daily hassles was associated with poorer perceptions of safety, being less able to practise safely and more workplace cognitive failure. Chronic stress did not moderate daily associations. The hassles reported illustrate the wide-ranging hassles nurses experienced. Conclusion: The findings demonstrate, in addition to chronic stress, the importance of daily hassles for nurses’ perceptions of safety and the hassles experienced by hospital nurses on a daily basis. Nurses perceive chronic stress and daily hassles to contribute to their perceptions of safety. Measuring the number of daily hassles experienced could proactively highlight when patient safety threats may arise, and as a result, interventions could usefully focus on the management of daily hassles

    Monitoring of cyanobacteria for water quality: doing the necessary right or wrong?

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    Cyanobacteria are an essential biological component of phytoplankton water quality assessment. However, there are some problems associated with the widely used everyday practices of sampling, estimation and use of cyanobacteria when calculating phytoplankton indices assessing water quality. Many indices were developed during the implementation of the Water Framework Directive, considered the most innovative European environmental legislation. Most indices include cyanobacteria as a composition or bloom metric. Problems with the indices concern the exclusion of most chroococcalean taxa from cyanobacterial biovolume estimations in lakes and reservoirs of the Mediterranean region, treatment of the mucilage of colonial chroococcalean taxa in biovolume estimations and overlooking of deep-water cyanobacterial blooms due to sampling depth. These problems may lead to a biased view of water quality. In this paper we argue in favour of including all cyanobacteria taxa and their mucilage in biovolume estimations and considering a sampling depth that covers deep-water maxima, such as those formed by Planktothrix rubescens or colonial chroococcalean taxa

    Morphological and molecular analysis of bloom-forming Cyanobacteria in two eutrophic, shallow Mediterranean lakes

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    We investigated the diversity of Cyanobacteria by microscopic observation and sequencing of cyanobacterial-specific amplified 16S rRNA genes in the water column of two shallow, eutrophic lakes (Doirani and Kastoria, northern Greece) during summer blooms. Previous phytoplankton studies in these lakes have shown that prolonged cyanobacterial blooms can occur, which are dominated by known toxic species, as well as other less known, co-occurring species. A total of 118 clones were sequenced which were grouped in 23 Cyanobacteria and 11 chloroplast-like phylotypes. Phylogenetic analysis revealed that each library included several unique phylotypes, as well as members of all common bloom-forming Cyanobacteria. Most of the phylotypes belonged to the genera Microcystis, Anabaena, Aphanizomenon, Cylindrospermopsis-Raphidiopsis group, Limnothrix and Planktothrix, comprising most of the diversity previously recognized by morphological observations in cyanobacterial morphospecies in these lakes. In addition, novel phylotypes belonging to the Chroococcales were recognized in both lakes. The structure of the cyanobacterial communities of the lakes were very similar, as revealed by 1 he diversity index H (2.06 and 2.01 for L Doirani and Kastoria, respectively) and LIBSHUFF analysis (XY(12) P-value = 0.122 and YX(12) P-value = 0.536), due to occurrence of groups of common phylotypes. This study gives an example for successful cyanobacterial bloom analysis by the combination of morphological and phylogenetic methods useful for monitoring cyanobacteria and water quality in freshwaters. (C) 2010 Elsevier GmbH. All rights reserved
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