927 resultados para MCQ, Multiple Choice Tests, Marking Scheme, Negative Marking, On-line Teaching


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The maintenance of colour polymorphisms within populations has been a long-standing interest in evolutionary ecology. African cichlid fish contain some of the most striking known cases of this phenomenon. Intrasexual selection can be negative frequency dependent when males bias aggression towards phenotypically similar rivals, stabilizing male colour polymorphisms. We propose that where females are territorial and competitive, aggression biases in females may also promote coexistence of female morphs. We studied a polymorphic population of the cichlid fish Neochromis omnicaeruleus from Lake Victoria, in which three distinct female colour morphs coexist: one plain brown and two blotched morphs. Using simulated intruder choice tests in the laboratory, we show that wild-caught females of each morph bias aggression towards females of their own morph, suggesting that females of all three morphs may have an advantage when their morph is locally the least abundant. This mechanism may contribute to the establishment and stabilization of colour polymorphisms. Next, by crossing the morphs, we generated sisters belonging to different colour morphs. We find no sign of aggression bias in these sisters, making pleiotropy unlikely to explain the association between colour and aggression bias in wild fish, which is maintained in the face of gene flow. We conclude that female-female aggression may be one important force for stabilizing colour polymorphism in cichlid fish.

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Both inter- and intrasexual selection have been implicated in the origin and maintenance of species-rich taxa with diverse sexual traits. Simultaneous disruptive selection by female mate choice and male-male competition can, in theory, lead to speciation without geographical isolation if both act on the same male trait. Female mate choice can generate discontinuities in gene flow, while male-male competition can generate negative frequency-dependent selection stabilizing the male trait polymorphism. Speciation may be facilitated when mating preference and/or aggression bias are physically linked to the trait they operate on. We tested for genetic associations among female mating preference, male aggression bias and male coloration in the Lake Victoria cichlid Pundamilia. We crossed females from a phenotypically variable population with males from both extreme ends of the phenotype distribution in the same population (blue or red). Male offspring of a red sire were significantly redder than males of a blue sire, indicating that intra-population variation in male coloration is heritable. We tested mating preferences of female offspring and aggression biases of male offspring using binary choice tests. There was no evidence for associations at the family level between female mating preferences and coloration of sires, but dam identity had a significant effect on female mate preference. Sons of the red sire directed significantly more aggression to red than blue males, whereas sons of the blue sire did not show any bias. There was a positive correlation among individuals between male aggression bias and body coloration, possibly due to pleiotropy or physical linkage, which could facilitate the maintenance of color polymorphism.

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OBJECTIVES To improve malnutrition awareness and management in our department of general internal medicine; to assess patients' nutritional risk; and to evaluate whether an online educational program leads to an increase in basic knowledge and more frequent nutritional therapies. METHODS A prospective pre-post intervention study at a university department of general internal medicine was conducted. Nutritional screening using Nutritional Risk Score 2002 (NRS 2002) was performed, and prescriptions of nutritional therapies were assessed. The intervention included an online learning program and a pocket card for all residents, who had to fill in a multiple-choice questions (MCQ) test about basic nutritional knowledge before and after the intervention. RESULTS A total of 342 patients were included in the preintervention phase, and 300 were in the postintervention phase. In the preintervention phase, 54.1% were at nutritional risk (NRS 2002 ≥3) compared with 61.7% in the postintervention phase. There was no increase in the prescription of nutritional therapies (18.7% versus 17.0%). Forty-nine and 41 residents (response rate 58% and 48%) filled in the MCQ test before and after the intervention, respectively. The mean percentage of correct answers was 55.6% and 59.43%, respectively (which was not significant). Fifty of 84 residents completed the online program. The residents who participated in the whole program scored higher on the second MCQ test (63% versus 55% correct answers, P = 0.031). CONCLUSIONS Despite a high ratio of malnourished patients, the nutritional intervention, as assessed by nutritional prescriptions, is insufficient. However, the simple educational program via Internet and usage of NRS 2002 pocket cards did not improve either malnutrition awareness or nutritional treatment. More sophisticated educational systems to fight malnutrition are necessary.

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Multiple osteochondromas (also called hereditary multiple exostoses) is an autosomal dominant disorder characterized by multiple cartilaginous tumors, which are caused by mutations in the genes for exostosin-1 (EXT1) and exostosin-2 (EXT2). The goal of this study was to elucidate the genetic alterations in a family with three affected members. Isolation of RNA from the patients' blood followed by reverse transcription and PCR amplification of selected fragments showed that the three patients lack a specific region of 90 bp from their EXT1 mRNA. This region corresponds to the sequence of exon 8 from the EXT1 gene. No splice site mutation was found around exon 8. However, long-range PCR amplification of the region from intron 7 to intron 8 indicated that the three patients contain a deletion of 4318 bp, which includes exon 8 and part of the flanking introns. There is evidence that the deletion was caused by non-homologous end joining because the breakpoints are not located within a repetitive element, but contain multiple copies of the deletion hotspot sequence TGRRKM. Exon 8 encodes part of the active site of the EXT1 enzyme, including the DXD signature of all UDP-sugar glycosyltransferases. It is conceivable that the mutant protein exerts a dominant negative effect on the activity of the EXT glycosyltransferase since it might interact with normal copies of the enzyme to form an inactive hetero-oligomeric complex. We suggest that sequencing of RNA might be superior to exome sequencing to detect short deletions of a single exon.

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Fragestellung/Einleitung: Prüfungen sind essentieller Bestandteil in der ärztlichen Ausbildung. Sie liefern wertvolle Informationen über den Entwicklungsprozess der Studierenden und wirken lernbegleitend und lernmodulierend [1], [2]. Bei schriftlichen Prüfungen dominieren derzeit Multiple Choice Fragen, die in verschiedenen Typen verwendet werden. Zumeist werden Typ-A Fragen genutzt, bei denen genau eine Antwort richtig ist. Multiple True-False (MTF) Fragen hingegen lassen mehrere richtige Antworten zu: es muss für jede Antwortmöglichkeit entschieden werden, ob diese richtig oder falsch ist. Durch die Mehrfachantwort scheinen MTF Fragen bestimmte klinische Sachverhalte besser widerspiegeln zu können. Auch bezüglich Reliabilität und dem Informationsgewinn pro Testzeit scheinen MTF Fragen den Typ-A Fragen überlegen zu sein [3]. Dennoch werden MTF Fragen bislang selten genutzt und es gibt wenig Literatur zu diesem Fragenformat. In dieser Studie soll untersucht werden, inwiefern die Verwendung von MTF Fragen die Nutzbarkeit (Utility) nach van der Vleuten (Reliabilität, Validität, Kostenaufwand, Effekt auf den Lernprozess und Akzeptanz der Teilnehmer) [4] schriftlicher Prüfungen erhöhen kann. Um die Testreliabilität zu steigern, sowie den Kostenaufwand für Prüfungen zu senken, möchten wir das optimale Bewertungssystem (Scoring) für MTF Fragen ermitteln. Methoden: Wir analysieren die Daten summativer Prüfungen der Medizinischen Fakultät der Universität Bern. Unsere Daten beinhalten Prüfungen vom ersten bis zum sechsten Studienjahr, sowie eine Facharztprüfung. Alle Prüfungen umfassen sowohl MTF als auch Typ-A Fragen. Für diese Prüfungen vergleichen wir die Viertel-, Halb- und Ganzpunktbewertung für MTF Fragen. Bei der Viertelpunktbewertung bekommen Kandidaten für jede richtige Teilantwort ¼ Punkt. Bei der Halbpunktbewertung wird ½ Punkt vergeben, wenn mehr als die Hälfte der Antwortmöglichkeiten richtig ist, einen ganzen Punkt erhalten die Kandidaten wenn alle Antworten richtig beantwortet wurden. Bei der Ganzpunktbewertung erhalten Kandidaten lediglich einen Punkt wenn die komplette Frage richtig beantwortet wurde. Diese unterschiedlichen Bewertungsschemata werden hinsichtlich Fragencharakteristika wie Trennschärfe und Schwierigkeit sowie hinsichtlich Testcharakteristika wie der Reliabilität einander gegenübergestellt. Die Ergebnisse werden ausserdem mit denen für Typ A Fragen verglichen. Ergebnisse: Vorläufige Ergebnisse deuten darauf hin, dass eine Halbpunktbewertung optimal zu sein scheint. Eine Halbpunktbewertung führt zu mittleren Item-Schwierigkeiten und daraus resultierend zu hohen Trennschärfen. Dies trägt zu einer hohen Testreliabilität bei. Diskussion/Schlussfolgerung: MTF Fragen scheinen in Verbindung mit einem optimalen Bewertungssystem, zu höheren Testreliabilitäten im Vergleich zu Typ A Fragen zu führen. In Abhängigkeit des zu prüfenden Inhalts könnten MTF Fragen einen wertvolle Ergänzung zu Typ-A Fragen darstellen. Durch die geeignete Kombination von MTF und Typ A Fragen könnte die Nutzbarkeit (Utility) schriftlicher Prüfungen verbessert werden.

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El crecimiento económico ha producido mejoras en el nivel de vida de la población que muchas veces tienen efectos medioambientales negativos en el largo plazo. Ante esta problemática, surge la necesidad a nivel empresarial de enmarcarse en un modelo de desarrollo sostenible que combine los objetivos de crecimiento económico con los de protección medioambiental. Esta situación puede representar altos costes para las empresas del sector petroquímico venezolano, debido al elevado riesgo de sus operaciones y al conjunto de regulaciones legales vigentes en materia medioambiental. Por lo tanto, el objetivo de la presente investigación ha sido proponer un modelo para la gestión de costes medioambientales de dicho sector fundamentado en la ecoeficiencia. Se planteó una investigación proyectiva, desde un enfoque holístico. Se utilizó un diseño de investigación univariable, transeccional contemporáneo, de fuente mixta. Univariable, porque se enfoca en la gestión de costes medioambientales como único evento a modificar. Transeccional contemporáneo, porque el evento se estudia en la actualidad y la medición de los datos se realiza en un solo momento. De fuente mixta, porque se combinó un diseño documental con un diseño de campo. Se utilizó un diseño documental para el análisis comparativo de las normativas de registro y control de costes medioambientales propuestas por organismos internacionales, mediante la aplicación de una matriz de análisis de categorías emergentes. Para el diagnóstico de la gestión de costes medioambientales en el sector petroquímico venezolano, se utilizó un diseño de campo en las empresas del sector que operan en la región zuliana. Para ello se aplicó un cuestionario con 100 ítems en escala Likert y 6 preguntas de opción múltiple. Dicho cuestionario fue validado mediante la revisión de expertos y se determinó su confiablidad a través del coeficiente alfa de Cronbach. Los resultados muestran que los principales asuntos tratados por las normativas analizadas pueden agruparse en seis temas: alcance de la contabilidad de gestión medioambiental, clasificación, tratamiento contable, asignación, informes de costes medioambientales e indicadores de gestión. Se evidenció que las guías de aplicación de la contabilidad de gestión medioambiental abordan todos los temas identificados pero no hay uniformidad en los criterios asumidos. Por el contrario, las normativas en el ámbito de la contabilidad financiera consideran principalmente los aspectos relacionados con el tratamiento contable de los costes medioambientales y su inclusión en los estados financieros. En cuanto a la gestión de costes medioambientales que realizan las empresas del sector petroquímico venezolano, se evidenció su limitación por la escasa consideración de criterios de ecoeficiencia y la poca aplicación de herramientas de contabilidad de gestión, que dificultan la determinación y el control de costes medioambientales. Tomando como base los resultados obtenidos, se diseñó el modelo de Gestión de Costes Medioambientales Ecoeficiente (GCME). Dicho modelo plantea como deben incorporarse los criterios de ecoeficiencia y las herramientas de contabilidad de gestión medioambiental para la planificación, coordinación y control en la gestión de costes medioambientales. Se plantea que estas etapas deben desarrollarse permanentemente para asegurar la mejora continua del proceso y su adaptación a los cambios tecnológicos y a las regulaciones legales. Se hace énfasis en las directrices que deben seguir las empresas del sector petroquímico venezolano para la aplicación del modelo GCME. Sin embargo, por su generalidad y adaptación a las Normas Internacionales de Contabilidad vigentes en Venezuela, dicho modelo es aplicable a diversos sectores industriales que requieran mejorar su desempeño económico-medioambiental. ABSTRACT Economic growth has led to improvements in the standard of living of the population that often have negative environmental effects over the long term. Faced with this problem, at the enterprise-level, the need to be framed in a sustainable development model that combines the goals of economic growth with environmental protection arises. This situation may represent high costs for the Venezuelan petrochemical companies due to the high risk of their operations and to all the applicable legal regulations on environmental matters. Therefore, this research aims to propose a model for the environmental costs management of these companies based on eco-efficiency. A projective research was performed from a holistic approach. An univariate, contemporary cross-sectional and mixed source research design was used. It is univariate, because it focuses on environmental costs management as the single event to change. It is contemporary cross-sectional, because the event is currently studied and the data measurement is performed in a single moment. It relies on mixed source, because it combines a documentary design with a field design. A documentary design was used for the comparative analysis of the standards of registration and control of environmental costs proposed by international organizations, by applying an analysis matrix of emerging categories. For the diagnosis of the environmental costs management in the Venezuelan petrochemical industry, a field design was applied in the companies that operate in the Zulia region. A questionnaire with 100 items on a Likert scale and 6 multiple-choice questions was used. The questionnaire was validated by peer review and internal consistency reliability was determined using Cronbach's alpha coefficient. The results show that the main issues addressed in the analyzed regulations can be grouped into six themes: scope of environmental management accounting, classification, accounting, allocation, reporting of environmental costs and performance indicators. It was evident that implementation guides of environmental management accounting address all issues identified but there is no uniformity in the assumed criteria. Meanwhile, regulations in the financial accounting field mainly consider aspects related to the accounting treatment of environmental costs and their inclusion in the financial statements. Regarding the environmental costs management performed by Venezuelan petrochemical companies, its limitations were made evident by the low status of eco-efficiency criteria and insufficient application of management accounting tools, which hinder the identification and control of environmental costs. Based on the results, the model of eco-efficient environmental costs management (EECM) was designed. This model indicates how eco-efficiency criteria and tools of environmental management accounting for planning, coordination and control in the environmental costs management should be incorporated. It argues that these stages must be continually developed to ensure a continuous process improvement and its adaptation to technological and legal regulatory changes. The guidelines which the Venezuelan petrochemical companies should follow for the EECM model application have been emphasized. However, due to its generality and adaptation to the International Accounting Standards enforced in Venezuela, this model is applicable to various industries that require an improvement of their economic and environmental performance.

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Abundant research has shown that poverty has negative influences on young child academic and psychosocial development, and unfortunately, disparities in school readiness between low and high income children can be seen as early the first year of life. The largest federal early care and education intervention for these vulnerable children is Early Head Start (EHS). To diminish these disparate child outcomes, EHS seeks to provide community based flexible programming for infants and toddlers and their families. Given how relatively recent these programs have been offered, little is known about the nuances of how EHS impacts infant and toddler language and psychosocial development. Using a framework of Community Based Participatory Research (CBPR) this paper had 5 goals: 1) to characterize the associations between domain specific and cumulative risk and child outcomes 2) to validate and explore these risk-outcome associations separately for Children of Hispanic immigrants (COHIs), 3) to explore relationships among family characteristics, multiple environmental factors, and dosage patterns in different EHS program types, 4) to examine the relationship between EHS dosage and child outcomes, and 5) to examine how EHS compliance impacts child internalizing and externalizing behaviors and emerging language abilities. Results of the current study showed that risks were differentially related to child outcomes. Poor maternal mental health was related to child internalizing and externalizing behaviors, but not related to emerging child language skills. Although child language skills were not related to maternal mental health, they were related to economic hardship. Additionally, parent level Spanish use and heritage orientation were associated with positive child outcomes. Results also showed that these relationships differed when COHIs and children with native-born parents were examined separately. Further, unique patterns emerged for EHS program use, for example families who participated in home-based care were less likely to comply with EHS attendance requirements. These findings provide tangible suggestions for EHS stakeholders: namely, the need to develop effective programming that targets engagement for diverse families enrolled in EHS programs.

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The protests on Kyiv’s Maidan which commenced in November 2013, followed by the conflict in Ukraine’s eastern regions, have redefined the political and social relations between Russia and Ukraine, and have added complexity to the dependences between the Orthodox Churches operating in the two countries. The Kremlin’s policy has put the Russian Orthodox Church–Moscow Patriarchate (ROC) in an awkward position. The ROC is Russia’s largest religious organisation, which also exercises symbolic sovereignty over Ukraine’s most numerous Orthodox community, the Ukrainian Orthodox Church–Moscow Patriarchate (UOC–MP), which since 13 August has had a new leader, Metropolitan Onufry. The head of the ROC, the Patriarch of Moscow and All-Russia, Kirill, has been facing a dilemma as to how he should respond to the Russian government’s aggressive policy towards Ukraine. His firm support of the Kremlin’s moves in Ukraine, may lose the Russian Church its social influence in this country. This might also catalyse a process within which Ukraine’s largest Orthodox Church would gradually become independent of Moscow. On the other hand, if he condemns the Kremlin’s policy, this would adversely affect the co-operation between ‘the altar and the throne’ which has been rapidly developing over the past few years in Russia, and which has offered multiple benefits to the Russian Church. As a result, Patriarch Kirill has distanced the ROC from the recent developments in Ukraine and has adopted a neutral stance. However, Kirill’s choice has aggravated the negative perception of the ROC among the Orthodox community in Ukraine. Given its close relations with the Kremlin, the ROC is increasingly viewed there as an instrument of political struggle and an exponent of the Russian government’s interests. The ROC’s stance has cast the UOC–MP, which has links with the Russian Church, in an unfavourable light, and has fostered its efforts to become more independent from the Moscow Patriarchate. Regardless of how the situation evolves, the recent developments in Ukraine have made it clear that the interests of the Russian Church and the Kremlin, which have coincided for years, now come into conflict, mainly due to the disagreement over the methods used. Despite this, the Russian Church is not withdrawing from the cooperation of ‘the altar and the throne’, and submits itself to the Kremlin’s decisions.

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Using multiple-choice feeding experiments, the selection of six species of macrophytes by the herbivorous rabbitfish Siganus fuscescens was examined. The rabbitfish showed distinct food choice in the laboratory; however, selection of macrophytes by S. fuscescens was not related to their absolute nutrient content (nitrogen, carbon, energy and ash free dry mass). Nutrient assimilation estimates showed that the macrophytes which were most preferred were those that S. fuscescens assimilated best. In S. fuscescens, the macrophytes that were preferred passed through the gut significantly faster than the less preferred species. Gut transit time had a significant effect on the absolute value of a food item in terms of net nutrient gain per unit time. This study showed that food value could be inferred from the absolute nutrient content of the macrophytes. Thus both the ability to assimilate nutrients as well as the absolute nutrient content of macrophytes must be quantified when assessing food value. (C) 2004 The Fisheries society of the British Isles.

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In this paper, we study the performance of smallholders in a nucleus estate and smallholder (NES) scheme in oil palm production schemein West Sumatra by measuring their technical efficiency using a stochastic frontier production function. Our results indicate a mean technical efficiency of 66%, which is below what we would have expected given the uniformity of the climate, soils and plantation construction among the sample farmers. The use of progressive farmers as a means of disseminating extension advice does not appear to have been successful, and more rigorous farmer selection procedures need to be put in place for similar schemes and for general agricultural extension in future. No clear relationship was established between technical efficiency and the use of female labour, suggesting there is no need to target extension services specifically at female labourers in the household. Finally, education was found to have an unexpectedly negative impact on technical efficiency, indicating that farmers with primary education may be more important than those with secondary and tertiary education as targets of development schemes and extension programs entailing non-formal education. (C) 2003 Elsevier Ltd. All rights reserved.

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Freshwater is extremely precious; but even more precious than freshwater is clean freshwater. From the time that 2/3 of our planet is covered in water, we have contaminated our globe with chemicals that have been used by industrial activities over the last century in a unprecedented way causing harm to humans and wildlife. We have to adopt a new scientific mindset in order to face this problem so to protect this important resource. The Water Framework Directive (European Parliament and the Council, 2000) is a milestone legislative document that transformed the way that water quality monitoring is undertaken across all Member States by introducing the Ecological and Chemical Status. A “good or higher” Ecological Status is expected to be achieved for all waterbodies in Europe by 2015. Yet, most of the European waterbodies, which are determined to be at risk, or of moderate to bad quality, further information will be required so that adequate remediation strategies can be implemented. To date, water quality evaluation is based on five biological components (phytoplankton, macrophytes and benthic algae, macroinvertebrates and fishes) and various hydromorphological and physicochemical elements. The evaluation of the chemical status is principally based on 33 priority substances and on 12 xenobiotics, considered as dangerous for the environment. This approach takes into account only a part of the numerous xenobiotics that can be present in surface waters and could not evidence all the possible causes of ecotoxicological stress that can act in a water section. The mixtures of toxic chemicals may constitute an ecological risk not predictable on the basis of the single component concentration. To improve water quality, sources of contamination and causes of ecological alterations need to be identified. On the other hand, the analysis of the community structure, which is the result of multiple processes, including hydrological constrains and physico-chemical stress, give back only a “photograph” of the actual status of a site without revealing causes and sources of the perturbation. A multidisciplinary approach, able to integrate the information obtained by different methods, such as community structure analysis and eco-genotoxicological studies, could help overcome some of the difficulties in properly identifying the different causes of stress in risk assessment. In synthesis, the river ecological status is the result of a combination of multiple pressures that, for management purposes and quality improvement, have to be disentangled from each other. To reduce actual uncertainty in risk assessment, methods that establish quantitative links between levels of contamination and community alterations are needed. The analysis of macrobenthic invertebrate community structure has been widely used to identify sites subjected to perturbation. Trait-based descriptors of community structure constitute a useful method in ecological risk assessment. The diagnostic capacity of freshwater biomonitoring could be improved by chronic sublethal toxicity testing of water and sediment samples. Requiring an exposure time that covers most of the species’ life cycle, chronic toxicity tests are able to reveal negative effects on life-history traits at contaminant concentrations well below the acute toxicity level. Furthermore, the responses of high-level endpoints (growth, fecundity, mortality) can be integrated in order to evaluate the impact on population’s dynamics, a highly relevant endpoint from the ecological point of view. To gain more accurate information about potential causes and consequences of environmental contamination, the evaluation of adverse effects at physiological, biochemical and genetic level is also needed. The use of different biomarkers and toxicity tests can give information about the sub-lethal and toxic load of environmental compartments. Biomarkers give essential information about the exposure to toxicants, such as endocrine disruptor compounds and genotoxic substances whose negative effects cannot be evidenced by using only high-level toxicological endpoints. The increasing presence of genotoxic pollutants in the environment has caused concern regarding the potential harmful effects of xenobiotics on human health, and interest on the development of new and more sensitive methods for the assessment of mutagenic and cancerogenic risk. Within the WFD, biomarkers and bioassays are regarded as important tools to gain lines of evidence for cause-effect relationship in ecological quality assessment. Despite the scientific community clearly addresses the advantages and necessity of an ecotoxicological approach within the ecological quality assessment, a recent review reports that, more than one decade after the publication of the WFD, only few studies have attempted to integrate ecological water status assessment and biological methods (namely biomarkers or bioassays). None of the fifteen reviewed studies included both biomarkers and bioassays. The integrated approach developed in this PhD Thesis comprises a set of laboratory bioassays (Daphnia magna acute and chronic toxicity tests, Comet Assay and FPG-Comet) newly-developed, modified tacking a cue from standardized existing protocols or applied for freshwater quality testing (ecotoxicological, genotoxicological and toxicogenomic assays), coupled with field investigations on macrobenthic community structures (SPEAR and EBI indexes). Together with the development of new bioassays with Daphnia magna, the feasibility of eco-genotoxicological testing of freshwater and sediment quality with Heterocypris incongruens was evaluated (Comet Assay and a protocol for chronic toxicity). However, the Comet Assay, although standardized, was not applied to freshwater samples due to the lack of sensitivity of this species observed after 24h of exposure to relatively high (and not environmentally relevant) concentrations of reference genotoxicants. Furthermore, this species demonstrated to be unsuitable also for chronic toxicity testing due to the difficult evaluation of fecundity as sub-lethal endpoint of exposure and complications due to its biology and behaviour. The study was applied to a pilot hydrographic sub-Basin, by selecting section subjected to different levels of anthropogenic pressure: this allowed us to establish the reference conditions, to select the most significant endpoints and to evaluate the coherence of the responses of the different lines of evidence (alteration of community structure, eco-genotoxicological responses, alteration of gene expression profiles) and, finally, the diagnostic capacity of the monitoring strategy. Significant correlations were found between the genotoxicological parameter Tail Intensity % (TI%) and macrobenthic community descriptors SPEAR (p<0.001) and EBI (p<0.05), between the genotoxicological parameter describing DNA oxidative stress (ΔTI%) and mean levels of nitrates (p<0.01) and between reproductive impairment (Failed Development % from D. magna chronic bioassays) and TI% (p<0.001) as well as EBI (p<0.001). While correlation among parameters demonstrates a general coherence in the response to increasing impacts, the concomitant ability of each single endpoint to be responsive to specific sources of stress is at the basis of the diagnostic capacity of the integrated approach as demonstrated by stations presenting a mismatch among the different lines of evidence. The chosen set of bioassays, as well as the selected endpoints, are not providing redundant indications on the water quality status but, on the contrary, are contributing with complementary pieces of information about the several stressors that insist simultaneously on a waterbody section providing this monitoring strategy with a solid diagnostic capacity. Our approach should provide opportunities for the integration of biological effects into monitoring programmes for surface water, especially in investigative monitoring. Moreover, it should provide a more realistic assessment of impact and exposure of aquatic organisms to contaminants. Finally this approach should provide an evaluation of drivers of change in biodiversity and its causalities on ecosystem function/services provision, that is the direct and indirect contributions to human well-being.

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The focus of this study is on the governance decisions in a concurrent channels context, in the case of uncertainty. The study examines how a firm chooses to deploy its sales force in times of uncertainty, and the subsequent performance outcome of those deployment choices. The theoretical framework is based on multiple theories of governance, including transaction cost analysis (TCA), agency theory, and institutional economics. Three uncertainty variables are investigated in this study. The first two are demand and competitive uncertainty which are considered to be industry-level market uncertainty forms. The third uncertainty, political uncertainty, is chosen as it is an important dimension of institutional environments, capturing non-economic circumstances such as regulations and political systemic issues. The study employs longitudinal secondary data from a Thai hotel chain, comprising monthly observations from January 2007 – December 2012. This hotel chain has its operations in 4 countries, Thailand, the Philippines, United Arab Emirates – Dubai, and Egypt, all of which experienced substantial demand, competitive, and political uncertainty during the study period. This makes them ideal contexts for this study. Two econometric models, both deploying Newey-West estimations, are employed to test 13 hypotheses. The first model considers the relationship between uncertainty and governance. The second model is a version of Newey-West, using an Instrumental Variables (IV) estimator and a Two-Stage Least Squares model (2SLS), to test the direct effect of uncertainty on performance and the moderating effect of governance on the relationship between uncertainty and performance. The observed relationship between uncertainty and governance observed follows a core prediction of TCA; that vertical integration is the preferred choice of governance when uncertainty rises. As for the subsequent performance outcomes, the results corroborate that uncertainty has a negative effect on performance. Importantly, the findings show that becoming more vertically integrated cannot help moderate the effect of demand and competitive uncertainty, but can significantly moderate the effect of political uncertainty. These findings have significant theoretical and practical implications, and extend our knowledge of the impact on uncertainty significantly, as well as bringing an institutional perspective to TCA. Further, they offer managers novel insight into the nature of different types of uncertainty, their impact on performance, and how channel decisions can mitigate these impacts.

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This study investigated the perceptions of writing among secondary and post-secondary students and their teachers. The focus was on students' writing philosophy and influences, perceptions of the writing process, and perceptions of student writing skills, high stakes assessment tests, and writing across the curriculum. ^ An ethnographic case study was used to investigate the perceptions of writing among ten students and their English teachers in two high schools, a community college, and a university. To establish balance and ethnic plurality, seven females and three males representing the four large ethnic groups in South Florida—African American, Haitian American, European American and Latino—participated. During one four-month term, data from written samples of students' writing, formal and informal interviews, a student focus group, field notes, classroom observations, and a “think-aloud” protocol were collected. ^ Four themes emerged. First, Florida's writing assessment test has a negative influence on students' perceptions of writing. Students' motivation and attitudes as well as their confidence in their abilities were affected by practice and preparation in “recital writing.” Second, writing is a vehicle of social and personal transformation. Students believed that writing is a mean to connect to others and to create change in schools and communities. Third, students lacked the ability to connect writing, thinking and learning. Although students and teachers agree with statements about this connection, students failed to see the relevance of thinking and learning through writing in current or future courses, or in their future careers. Finally, writing context, teachers, schools, peers and gender influenced writing perceptions. Students believed that their writing philosophy, writing process, and perceptions of writing in academia and in the workplace are connected to these five factors. ^ The effect of the Florida writing test pervades students' and teachers' writing perceptions, making a stronger case for writing across the curriculum than previous research. Writing should help students see knowledge as interrelated, honor students' interests and values, and build relationships between and among students, schools and communities. In designing and implementing methods that support and sustain student writing, teachers should provide students with multiple opportunities to expand knowledge, learning, and connection through writing. ^

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This study investigated the effects of augmented prenatal auditory stimulation on postnatal visual responsivity and neural organization in bobwhite quail (Colinus virginianus). I delivered conspecific embryonic vocalizations before, during, or after the development of a multisensory, midbrain audiovisual area, the optic tectum. Postnatal simultaneous choice tests revealed that hatchlings receiving augmented auditory stimulation during optic tectum development as embryos failed to show species-typical visual preferences for a conspecific maternal hen 72 hours after hatching. Auditory simultaneous choice tests showed no hatchlings had deficits in auditory function in any of the groups, indicating deficits were specific to visual function. ZENK protein expression confirmed differences in the amount of neural plasticity in multiple neuroanatomical regions of birds receiving stimulation during optic tecturn development, compared to unmanipulated birds. The results of these experiments support the notion that the timing of augmented prenatal auditory stimulation relative to optic tectum development can impact postnatal perceptual organization in an enduring way.^

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Non-native predators may have negative impacts on native communities, and these effects may be dependent on interactions among multiple non-native predators. Sequential invasions by predators can enhance risk for native prey. Prey have a limited ability to respond to multiple threats since appropriate responses may conflict, and interactions with recent invaders may be novel. We examined predator–prey interactions among two non-native predators, a recent invader, the African jewelfish, and the longer-established Mayan cichlid, and a native Florida Everglades prey assemblage. Using field enclosures and laboratory aquaria, we compared predatory effects and antipredator responses across five prey taxa. Total predation rates were higher for Mayan cichlids, which also targeted more prey types. The cichlid invaders had similar microhabitat use, but varied in foraging styles, with African jewelfish being more active. The three prey species that experienced predation were those that overlapped in habitat use with predators. Flagfish were consumed by both predators, while riverine grass shrimp and bluefin killifish were eaten only by Mayan cichlids. In mixed predator treatments, we saw no evidence of emergent effects, since interactions between the two cichlid predators were low. Prey responded to predator threats by altering activity but not vertical distribution. Results suggest that prey vulnerability is affected by activity and habitat domain overlap with predators and may be lower to newly invading predators, perhaps due to novelty in the interaction.