Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Utilisation

  • drug utilisation
  • good utilisation
  • habitat utilisation
  • health services utilisation
  • healthcare utilisation
  • research utilisation
  • resource utilisation
  • service utilisation
  • services utilisation

  • Terms modified by Utilisation

  • utilisation efficiency
  • utilisation pattern

  • Selected Abstracts

    Can a publicly funded home care system successfully allocate service based on perceived need rather than socioeconomic status?

    A Canadian experience
    Abstract The present quantitative study evaluates the degree to which socioeconomic status (SES), as opposed to perceived need, determines utilisation of publicly funded home care in Ontario, Canada. The Registered Persons Data Base of the Ontario Health Insurance Plan was used to identify the age, sex and place of residence for all Ontarians who had coverage for the complete calendar year 1998. Utilisation was characterised in two dimensions: (1) propensity , the probability that an individual received service, which was estimated using a multinomial logit equation; and (2) intensity , the amount of service received, conditional on receipt. Short- and long-term service intensity were modelled separately using ordinary least squares regression. Age, sex and co-morbidity were the best predictors (P < 0.0001) of whether or not an individual received publicly funded home care as well as how much care was received, with sicker individuals having increased utilisation. The propensity and intensity of service receipt increased with lower SES (P < 0.0001), and decreased with the proportion of recent immigrants in the region (P < 0.0001), after controlling for age, sex and co-morbidity. Although the allocation of publicly funded home care service was primarily based on perceived need rather than ability to pay, barriers to utilisation for those from areas with a high proportion of recent immigrants were identified. Future research is needed to assess whether the current mix and level of publicly funded resources are indeed sufficient to offset the added costs associated with the provision of high-quality home care. [source]

    Skill Formation and Utilisation in the Post-Soviet Transition: Higher Education Planning in Post-Soviet Georgia

    Irakli GvaramadzeArticle first published online: 1 MAR 2010
    Changes in the former Soviet system had a dramatic influence on higher education in Georgia. The main objective of the current article is to analyse implications of the post-Soviet transition for the skill formation and skill utilisation system in Georgia. In particular, the study analyses recent trends in Georgian higher education including privatisation and economic liberalisation. The discussion builds upon theories of transition and relevance of skill formation theories to the post-Soviet transition. The article argues that increasing competition among public universities and newly emerged private universities has not improved the quality of higher education provision. On the contrary, it has contributed to an imbalance between the labour market's demand for skills and awarded qualifications, a mismatch and irrelevance of skills and high unemployment rates among university graduates. The article demonstrates that economic approaches in the transition context could not explain the complex logic between the skill formation and skill utilisation mechanisms. It further concludes that the discrepancies between the skill formation and skill utilisation systems had a negative impact upon skill modernisation in Georgia. [source]

    Use of Nursing Diagnoses and Interventions in Public Health Nursing Practice

    Jennifer C. Rivera MSN
    PURPOSE. To determine the frequency of use of NANDA diagnoses and the Nursing Interventions Classification in care plans written by public health nurses (PHNs) in Orange County, CA. METHODS.Retrospective chart review. FINDINGS. The frequency pattern of nursing diagnoses and nursing interventions used in care plans is consistent with the scope of practice of the PHN, whose emphasis is on health promotion and disease prevention. CONCLUSIONS. The most commonly used diagnoses and interventions provide evidence of a core set of interventions useful for PHN practice. IMPLICATIONS FOR PRACTICE.Linking diagnoses and interventions allow PHNs to build a body of knowledge based on patient care and improve clinical decision-making process. Search terms:Interventions, nursing diagnosis, public health nursing Utilisation des diagnostics infirmiers et interventions en santé publique BUT.Déterminer la fréquence des diagnostics infirmiers (ANADI) et des interventions (NIC) dans les plans de soins rédigés par les infirmières de santé publique dans le Comté d'Orange, CA. METHODE.Étude rétrospective des dossiers. RÉSULTATS.La répartition des diagnostics infirmiers et des interventions utilisés dans les plans de soin est cohérente avec la pratique des infirmières en santé publique, c'est-à-dire qu'elle souligne l'importance de la promotion de la santé et la prévention de la maladie. CONCLUSIONS.Les diagnostics et interventions les plus fréquemment utilisés permettent d'identifier le groupe d'interventions au centre de la pratique des soins en santé publique. IMPLICATIONS POUR LA PRATIQUE.L'articulation des diagnostics et interventions de soins permet de construire un corpus de connaissances en santé publique basée sur le soin des patients et d'améliorer le processus de décision clinique. Mots-clés:Diagnostics infirmiers, interventions, soins infirmiers en santé publique Utilización de los diagnósticos e intervenciones de enfermería en la práctica de enfermería de salud pública PROPÓSITO.Determinar la frecuencia del uso de los diagnósticos de la NANDA y de la clasificación de las intervenciones enfermeras (NIC), en planes del cuidados escritos por enfermeras de salud pública en el Condado de Orange, California. MÉTODOS.Revisión retrospectiva de gráficos. RESULTADOS. El patrón de frecuencia de diagnósticos de enfermería y de intervenciones enfermeras utilizados en los planes del cuidados, es consistente con el ámbito asistencial de las enfermeras de salud pública, cuyo énfasis está en la promoción de salud y la prevención de la enfermedad. CONCLUSIÓN.Los diagnósticos e intervenciones más comúnmente utilizados, proporcionan evidencia de un grupo nuclear de intervenciones útiles a la práctica de enfermería de salud pública. IMPLICACIONES PARA LA PRÁCTICA.Conectar los diagnósticos y las intervenciones permite a las Enfermeras de Salud Pública construir un cuerpo de conocimientos basado en el cuidado de los pacientes y mejorar el proceso de toma de decisiones en la práctica clínica. Términos de búsqueda:Diagnóstico enfermero, enfermería de salud pública, intervenciones Uso de diagnósticos e intervenções de enfermagem na prótica de enfermagem em Saúde Pública OBJETIVO.Determinar a freqüência de uso dos diagnósticos da NANDA e da Classificação de Intervenções de Enfermagem (NIC) em planos de cuidados escritos por enfermeiras da área de Saúde Pública no Condado de Orange, Califórnia. MÉTODO.Revisão retrospectiva de fichas. ACHADOS.O padrão de freqüência de diagnósticos de enfermagem e intervenções de enfermagem utilizados em planos de cuidados é compatível com o escopo da prática das enfermeiras da área de Saúde Pública, cuja ênfase está na promoção da saúde e prevenção de doenças. CONCLUSãO.Os diagnósticos e intervenções mais comumente utilizados evidenciam a existência de um conjunto de intervenções principais, que éútil para a prática destas enfermeiras. IMPLICAÇõES PARA A PRÁTICA. A ligação entre diagnósticos e intervenções permite às enfermeiras da área de saúde pública construírem um corpo de conhecimentos baseado no cuidado do paciente e melhora o processo de tomada de decisão. Palavras para busca:Diagnóstico de enfermagem, enfermagem em saúde publica, intervenções [source]

    Utilisation of morphological features in life table studies of Liriomyza huidobrensis (Dipt., Agromyzidae) developing in lettuce

    J. Head
    The growth ratios of cephalopharyngeal skeletons between first and second and second and third instar larvae were 1.80 and 1.47, respectively, enabling clear separation to be achieved for experimental work. Using this method the development rates of the immature stages of L. huidobrensis feeding on Lactuca sativa were determined under constant temperatures of 11, 16, 19, 26 and 28 ± 1°C and were shown to increase linearly with temperature over the range investigated. The theoretical lower threshold temperatures for development from oviposition to the end of each larval instar or pupal stage were 5.35, 6.30, 6.20 and 5.70°C, respectively. The overall threshold temperature for development from oviposition to 50% adult emergence (5.70°C) was used to calculate degree-day (DD) requirements for development from oviposition to each larval instar or pupal eclosion, which were 84.3, 30.1, 58.9, 143.7 DD, respectively. The use of these data for optimizing the timing of application of control agents which are effective against specific developmental stages is discussed. [source]

    Utilisation of C2,C4 gaseous hydrocarbons and isoprene by microorganisms

    Jean L Shennan
    Abstract Microorganisms able to grow on low molecular weight aliphatic hydrocarbon gases, i.e. the n -alkanes, ethane, propane and butane, and the terminal alkenes, ethylene, propylene and butylene, are not uncommon but mainly belong to certain taxonomic groups. These microbes are described in this review together with the pathways by which the hydrocarbons are assimilated. Microbial oxidation of the volatile alkadiene, isoprene, is also discussed. Avenues for possible commercial exploitation of these metabolic activities are also reviewed. Short-chain n -alkane-utilising organisms have been investigated as tools in petroleum exploration and for production of single cell protein. More recently microbes grown on gaseous hydrocarbons other than methane have been evaluated for use in biotechnological production of epoxides, synthesis of chiral epoxyalkanes and as catalysts in bioremediation systems. Copyright © 2005 Society of Chemical Industry [source]

    Utilisation of electrospray time-of-flight mass spectrometry for solving complex fragmentation patterns: application to benzoxazinone derivatives

    L. S. Bonnington
    Abstract In this paper we describe the application of electrospray time-of-flight mass spectrometry (ESI-TOFMS) to structural elucidation of the fragment ions formed from a range of natural and synthetic allelochemical derivatives. The extensive mass spectrometric characterisation of ten non-glucosylated benzoxazinone derivatives using this method is described here for the first time. The analytes include six naturally occurring 1,4-benzoxazin-3(4H)-one derivatives, including the hydroxamic acids DIMBOA [2,4-dihydroxy-7-methoxy-2H -1,4-benzoxazin-3(4H)-one] and DIBOA [2,4-dihydroxy-2H -1,4-benzoxazin-3(4H)-one], lactams HBOA [2-hydroxy-2H -1,4-benzoxazin-3(4H)-one] and HMBOA [2-hydroxy-7-methoxy-2H -1,4-benzoxazin-3(4H)-one], benzoxazolinones BOA [benzoxazolin-2(3H)-one] and MBOA [6-methoxy-benzoxazolin-2(3H)-one] and four synthetic variations, 2,H-DIBOA [4-hydroxy-2H -1,4-benzoxazin-3(4H)-one], 2,OMe-DIBOA [2-methoxy-4-hydroxy-2H -1,4-benzoxazin-3(4H)-one], 2,H-HBOA [2H -1,4-benzoxazin-3(4H)-one] and 2,OMe-HBOA [2-methoxy-2H -1,4-benzoxazin-3(4H)-one]. Assignments of the mass spectral fragments were aided by elemental composition calculation results, comparison of structural analogues and background literature, and acquired knowledge regarding feasible structures for the compounds. The influence of substituents on the chemical reactivity of the compounds with respect to the observed MS behaviour over varying nozzle potentials is addressed and, through comparison of the structural analogues, generic fragmentation patterns have also been identified. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    Utilisation of separation methods in the analysis of chemical warfare agents

    Barbora Papou
    Abstract Chemical warfare agents and their degradation products represent a broad group of compounds with different chemical properties (polarity, volatility, thermostability, etc.). These chemicals often have to be detected and determined in complex matrices and therefore highly efficient separation techniques hyphenated to selective and sensitive detectors play an indispensable role. This review offers an overview of selected papers devoted to the title subject. It cannot be considered as a comprehensive literature compilation but should allow the reader to obtain an insight into the application of separation techniques in the important area of human protection and control of chemical weapons. [source]

    Utilisation of corn (Zea mays) bran and corn fiber in the production of food components,

    Devin J Rose
    Abstract The milling of corn for the production of food constituents results in a number of low-value co-products. Two of the major co-products produced by this operation are corn bran and corn fiber, which currently have low commercial value. This review focuses on current and prospective research surrounding the utilization of corn fiber and corn bran in the production of potentially higher-value food components. Corn bran and corn fiber contain potentially useful components that may be harvested through physical, chemical or enzymatic means for the production of food ingredients or additives, including corn fiber oil, corn fiber gum, cellulosic fiber gels, xylo-oligosaccharides and ferulic acid. Components of corn bran and corn fiber may also be converted to food chemicals such as vanillin and xylitol. Commercialization of processes for the isolation or production of food products from corn bran or corn fiber has been met with numerous technical challenges, therefore further research that improves the production of these components from corn bran or corn fiber is needed. Published 2010 by John Wiley & Sons, Ltd. [source]

    Fretting fatigue strength of SCM435H steel and SUH660 heat-resistant steel in hydrogen gas environment

    M. Kubota
    Abstract Utilisation of hydrogen is expected to be one of the solutions against the problems of exhaustion of fossil fuels and reduction of carbon dioxide emissions. Evaluation of the materials for hydrogen utilisation machines is required. The objectives of this study are the characterisation of fretting fatigue strength of low-alloy steel SCM435H and heat-resistant steel SUH660, and the validation of effectiveness of nitriding in hydrogen gas environment. Fretting fatigue tests were conducted up to 3 × 107 cycles. The decrease of fretting fatigue strength in hydrogen gas environment was found at the long-life region exceeding 107 cycles. The amount of the decrease of the fretting fatigue limit at 3 × 107 cycles was 11% for SCM435H and 15% for SUH660. However, at the stress level above the fretting fatigue limit in air, the finite life in hydrogen gas increased more than that in air. The cause of extension of fatigue life was the delay of start of stable crack propagation. Fretting fatigue crack, which was smaller than 200,µm in length, consumed approximately 60% of the fatigue life in hydrogen gas environment. Fretting fatigue crack was steadily propagated after the test was started in air. Observations of the fretted surface showed that the fretting wear process in hydrogen gas environment was dominated by adhesion. Tangential force coefficient was higher in hydrogen gas environment than that in air. It is considered that the adhesion has a close relation to crack initiation in hydrogen gas environment, and as a result, the failure of specimen occurred at a lower stress level comparing the fretting fatigue limit in air. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Social Inequality: Utilisation of general practitioner services by socio-economic disadvantage and geographic remoteness

    Gavin Turrell
    Objective: To examine the association between socio-economic status (SES) and GP utilisation across Statistical Local Areas (SLAs) that differed in their geographic remoteness, and to assess whether Indigenous status and GP availability modified the association. Design: Retrospective analysis of Medicare data for all unreferred GP consultations (1996/97) for 952 SLAs comprising the six Australian States. Geographic remoteness was ascertained using the Area Remoteness Index of Australia (ARIA), and SES was measured by grouping SLAs into tertiles based on their Index of Relative Socioeconomic Disadvantage score. Main outcome measure: Age/sex standardised rates of GP utilisation for each SLA. Main results: In SLAs classified as ,highly accessible', rates of GP use were 10.8% higher (95% CI 5.7,16.0) in the most socio-economically disadvantaged tertile after adjustment for Indigenous status and GP availability. A very different pattern of GP utilsation was found in ,remote/very remote' SLAs. After adjustment, rates of GP use in the most socio-economically disadvantaged tertile were 25.3% lower (95% CI 5.9,40.7) than in the most advantaged tertile. Conclusions: People in socio-economically disadvantaged metropolitan SLAs have higher rates of GP utilisation, as would be expected due to their poorer health. This is not true for people living in disadvantaged remote/very remote SLAs: in these areas, those most in need of GP services are least likely to receive them. Australia may lay claim to having a primary health care system that provides universal coverage, but we are still some way from having a system that is economically and geographically accessible to all. [source]

    Maternal mortality in Yunnan, China: recent trends and associated factors

    J Li
    Objective, Yunnan Province, located in southwest China, is one of the poorest province in China. The maternal mortality ratio (MMR) is about twice the national average (56.2/100 000 live births), and in remote mountainous regions, the rate is five times higher. This study aimed to examine the progress in reduction of maternal mortality in the 1990s and early 2000s and the factors associated with this reduction in Yunnan. Design, A population-based, longitudinal, ecological correlation study. Setting, A remote province of China with a proportionately large indigenous population. Population, Populations at county, prefecture and provincial level. Methods, Using maternal mortality data collected at the province, prefecture/region and county levels, trend and time series analyses and multivariate linear regression analyses were performed using SPSS (Version 13). Main outcome measure, MMR and its change over time. Results, MMR declined substantially in the 1990s at a rate of 3.0% per year. Utilisation of prenatal and obstetric care increased and was significantly correlated with the declining trend in MMR. Hospital delivery was a strong predictor of MMR, independent of social and economic development. Both low income and illiteracy were significantly associated with increased MMR. Conclusions, Declines in maternal mortality in Yunnan over the past 14 years appear to reflect health, social and economic interventions implemented in the 1990s. The association of hospital delivery with maternal mortality may be due to the effective management of severe pregnancy and birth complications. Low income and illiteracy were associated with MMR but primarily through their impact on the use of prenatal and obstetric care. [source]

    Benefiting from Commissioned Research: The Role of Researcher , Client Cooperation

    Geir Grundvåg Ottesen
    This paper discusses why commissioned research is often neglected and misunderstood, as well as how its use can be enhanced. We argue that the lack of use of such research can be attributed to differences in researchers' and practitioners' knowledge and expectations regarding research problems, solutions, interpretations, and applications. Two hypotheses are proposed, which link the use of research to cooperation between researchers and users during the production of the research, and to assistance in interpreting and applying the research results. The hypotheses were tested on a sample of 65 buyers of 86 research projects in the seafood industry. The reported findings reveal that collaboration fosters research utilisation, but also that close cooperation between the providers and the users of research may substitute assistance in enhancing research utilisation. [source]


    Michael F. Fay
    Summary. Plants that parasitise other plants have been among the most difficult plant groups to fit into classification systems due to their modified biology and their often highly reduced morphology. They are now considered to be found in about 16 families of flowering plants. Here we summarise current ideas about their relationships and provide information about their characteristics and utilisation. A major consequence of the revised classification of Orobanchaceae and related families has been the break-up of the traditional Scrophulariaceae, and here we summarise the new classification, focusing on genera of horticultural interest. [source]

    Low-fat oxidation may be a factor in obesity among men with schizophrenia

    J.-K. Sharpe
    Objective:, Obesity associated with atypical antipsychotic medications is an important clinical issue for people with schizophrenia. The purpose of this project was to determine whether there were any differences in resting energy expenditure (REE) and respiratory quotient (RQ) between men with schizophrenia and controls. Method:, Thirty-one men with schizophrenia were individually matched for age and relative body weight with healthy, sedentary controls. Deuterium dilution was used to determine total body water and subsequently fat-free mass (FFM). Indirect calorimetry using a Deltatrac metabolic cart was used to determine REE and RQ. Results:, When corrected for FFM, there was no significant difference in REE between the groups. However, fasting RQ was significantly higher in the men with schizophrenia than the controls. Conclusion:, Men with schizophrenia oxidised proportionally less fat and more carbohydrate under resting conditions than healthy controls. These differences in substrate utilisation at rest may be an important consideration in obesity in this clinical group. [source]

    Perennialism and Poverty Reduction

    Nigel D. Poole
    This article, which is both conceptual and a synthesis of the literature, considers the research component of poverty alleviation strategies for people whose livelihoods depend significantly on tree and forest resources. Two policy approaches are contrasted: enhancing the utilisation of indigenous tree species within the household and the local economy, and integrating tree and forest-dependent peoples into the wider economy by promoting the commercialisation of conventional tree crop production. It is argued that the discussion is relevant for other poor peoples who depend on perennial production systems, and that the conclusions contribute to the wider debate about remoteness, market access, decentralisation and targeting in policy formulation, and globalisation. [source]

    The relationship between peripheral glucose utilisation and insulin sensitivity in the regulation of hepatic glucose production: studies in normal and alloxan-diabetic dogs

    M. J. Christopher
    Abstract Background Hepatic glucose overproduction (HGP) of diabetes could be primary or could occur in response to the metabolic needs of peripheral (skeletal muscle (SkM)) tissues. This question was tested in normal and diabetic dogs. Methods HGP, SkM glucose uptake (Rdtissue), metabolic clearance of glucose (MCRg) and glycolytic flux (GFexog), and SkM biopsies were measured in the same dogs before and after alloxan-induced diabetes. Normal dogs were exposed to (1) an extended 20-h fast, (2) low- and high-dose glucose infusions (GINF) at basal insulinaemia, and chronic diabetic dogs were exposed to (3) hyperglycaemia, (4) phlorizin-induced normoglycaemia, and (5) poor and good diabetic control. Results (1) Prolonged fast: HGP, Rdtissue, and GFexog fell in parallel (p < 0.05). (2) Low-dose GINF: plasma glucose, insulin, Rdtissue, MCRg, and GFexog were unchanged, but HGP fell by ,40%, paralleling the supplemental GINF. (3) High-dose GINF at basal insulin: plasma glucose doubled and synchronous changes in HGP, Rdtissue, MCRg, and GFexog occurred; ICglucose, G6P, and glycogen were unchanged. (4) Hyperglycaemic diabetes: HGP was raised (p < 0.05), matching urinary glucose loss (UGL) and decreased MCRg, and maintaining normal basal Rdtissue and GFexog. SkM ICglucose was increased and glycogen decreased (both p < 0.05). (5) Phlorizin-induced normoglycaemia in diabetic dogs: HGP rose, matching the increased UGL, while maintaining normal Rdtissue and GFexog. Intramuscular substrates normalised. (6) Whole body and SkM metabolism normalised with correction of the insulin resistance and good diabetic control. Conclusion HGP reflects whether SkM is in a state of relative glucose ,excess' or absolute/relative glucose ,deprivation'. Copyright © 2005 John Wiley & Sons, Ltd. [source]

    Restoring sanitation services after an earthquake: field experience in Bam, Iran

    DISASTERS, Issue 3 2005
    Jean-François Pinera
    Abstract A powerful earthquake hit the city of Bam in southeast Iran on 26 December 2003. In its aftermath, a number of international relief agencies, including Oxfam, assisted in providing emergency sanitation services. Oxfam's programme consisted of constructing and repairing toilets and showers in villages located outside of the city. In contrast with other organisations, Oxfam opted for brickwork structures, using local materials and human resources rather than prefabricated cubicles. The choice illustrates the dilemmas faced by agencies involved in emergency sanitation: responding to needs in a manner consistent with international standards and offering assistance in a timely fashion while involving beneficiaries. Following a preliminary survey, Oxfam concluded that the provision of showers and latrines, in addition to utilisation of local materials and human resources, was essential for ensuring well-being, empowerment and dignity among members of the affected population, thereby maximising the benefits. [source]

    Spatial utilisation of fast-ice by Weddell seals Leptonychotes weddelli during winter

    ECOGRAPHY, Issue 3 2005
    Samantha Lake
    This study describes the distribution of Weddell seals Leptonychotes weddelli in winter (May,September 1999) at the Vestfold Hills, in Prydz Bay, East Antarctica. Specifically, we describe the spatial extent of haul-out sites in shore,fast sea-ice, commonly referred to as fast-ice. As winter progressed, and the fast-ice grew thick (ca 2 m), most of the inshore holes closed over, and the seals' distribution became restricted to ocean areas beyond land and islands. Using observations from the end of winter only, we fitted Generalised Additive Models (GAMs) to generate resource selection functions, which are models that yield values proportional to the probability of use. The models showed that seal distribution was defined mainly by distance to ice-edge and distance to land. Distance to ice-bergs was also selected for models of some regions. We present the results as maps of the fitted probability of seal presence, predicted by the binomial GAM for offshore regions, both with and without autocorrelation terms. The maps illustrate the expected distribution encompassing most of the observed distribution. On this basis, we hypothesise that propensity for the fast-ice to crack is the major determinant of Weddell seal distribution in winter. Proximity to open water and pack-ice habitats could also influence the distribution of haul-out sites in fast-ice areas. This is the first quantitative study of Weddell seal distribution in winter. Potential for regional variation is discussed. [source]

    Scale dependence of spatial patterns and cartography on the detection of landscape change: relationships with species' perception

    ECOGRAPHY, Issue 4 2002
    Susana Suárez-Seoane
    This paper analyses how landscape pattern detection changes when different spatial and temporal scales and several levels of detail of the cartography are used to describe a landscape affected by land abandonment in northern Spain. In order to integrate landscape composition and structure at different temporal and spatial scales in the same framework, a multiple correspondence factorial analysis was ran for each typology of landscape units. Annual rates of change and scale dependencies were calculated for each typology from the Euclidean distances in the factorial space. Finally, the potential assessment of habitat utilisation by species with different landscape perception and movement capacity was modelled for the range of typologies. The amount of variance explained by the factorial analysis decreased with the complexity of the typology. Annual rates of change appeared different according to the time span and the detail of the landscape unit typology used. For all typologies, changes were faster during 1983,95, a period characterised by massive land abandonment. However, when the whole period (1956,95) was considered, annual changes were much lower, showing differences between typologies. As a general trend, the variance of the mean annual change decreased with the size of the analysis units. In response to land abandonment, different scale dependencies were found for different levels of detail of the cartography. Coarser typologies are suitable when analysing highly mobile species. However, species with small movement capacity or with a preference for homogeneous habitats perceive more detail in landscape. In this case, a detailed typology is more appropriate. [source]

    Post-ingestive effects of nectar alkaloids depend on dominance status of bumblebees

    Abstract 1.,Secondary metabolites have acute or chronic post-ingestive effects on animals, ranging from death to growth inhibition to reduced nutrient assimilation. 2.,Although characterised as toxic, the nectar of Gelsemium sempervirens is not lethal to pollinators, even when the concentration of the nectar alkaloid gelsemine is very high. However, little is known about the sublethal costs of nectar alkaloids. 3.,Using a microcolony assay and paired worker bumblebees, the present study measured the effects of artificial nectar containing gelsemine on oocyte development. Oocytes are a sensitive indicator of protein utilisation and general metabolic processes. We also calculated carbohydrate concentrations in the haemolymph to examine energetic costs of gelsemine consumption. 4.,High concentrations of gelsemine significantly reduced mean oocyte width in subordinate bees, while dominant bees showed only a trend towards oocyte inhibition. Gelsemine consumption did not reduce carbohydrate concentrations in haemolymph. 5.,The cost of ingesting gelsemine may be due to direct toxicity of alkaloids or may be an expense associated with detoxifying gelsemine. Detoxification of alkaloids can require reallocation of resources away from essential metabolic functions like reproduction. The risks associated with nectar alkaloid consumption are tied to both the social and nutritional status of the bee. [source]

    Fungivore host-use groups from cluster analysis: patterns of utilisation of fungal fruiting bodies by ciid beetles

    Glenda M. Orledge
    Abstract., 1.,Ciid beetles typically live and breed in the fruiting bodies of lignicolous basidiomycete fungi. This study was undertaken to address the lack of an objective examination of patterns of host use by ciids. 2.,Cluster analysis of ciid host-use datasets from Britain, Germany, North America, and Japan, and subsequent cross-dataset comparisons, demonstrated the existence of ciid host-use patterns of wide geographical occurrence. These patterns were formalised as ciid host-use groups. 3.,Six Holarctic ciid host-use groups, and two host-use subgroups, were identified, and are described. Each host-use group comprises an assemblage of fungal genera and the breeding ciids that it supports. Each taxon belongs to only a single host-use group, but may be associated with several members of that group. There is a strong tendency for closely related taxa to belong to the same host-use group. 4.,It is suggested that ciid host-use groups are defined ultimately by host chemistry, with the ciids that belong to a particular group recognising, and responding positively to, emitted volatiles characterising the fungi belonging to that group. 5.,The idea of the host-use group bears comparison with the concepts of niche and guild, but is not equivalent to either. 6.,Ciid host-use groups have a valuable role to play in underpinning future studies of ciid ecology, also the systematics of both ciids and their fungal hosts. [source]

    The significance of overlapping plant range to a putative adaptive trade-off in the black bean aphid Aphis fabae Scop

    C. R. Tosh
    Abstract., 1. This study continues to explore the analysis of a putative adaptive trade-off in the utilisation of host plants Vicia faba and Tropaeolum majus by the aphid, Aphis fabae. These plants are utilised exclusively by the subspecies Aphis fabae fabae and A. f. mordwilkoi respectively, and this plant-use system has been studied previously as a potential source of disruptive selection. 2. Here the potential of these two host plants to generate disruptive selection is considered given common utilisation of the abundant host plant, Rumex obtusifolius, by both subspecies. 3. The life history of subspecific clones is quantified in the laboratory on V. faba, T. majus, and R. obtusifolius at various temperatures and used to parameterise a temperature-driven simulation model of aphid population development. 4. Accuracy of the model is tested using a field experiment, and fitness of clones on specific and common host is simulated using temperature data from a number of English sites. 5. The model gives a close quantitative fit to field data and makes the following predictions: performance of A. f. fabae is higher on the specific host than the common host under all tested thermal regimes; and performance of A. f. mordwilkoi is superior on the specific host in warm years but inferior in cold years. 6. Given the great abundance of R. obtusifolius relative to T. majus, the model predicts that the plant utilisation system has little potential to consistently promote hybrid dysfunction. This adds further weight to the assertion that the plant utilisation system studied can offer little insight into the evolutionary processes involved in subspecific differentiation and probably contains a host plant/host plants acquired after the evolution of reproductive barriers. [source]

    Colony productivity and foundress behaviour of a native wasp versus an invasive social wasp

    Tracy R. Armstrong
    Abstract., 1.,Colony productivity, prey utilisation, and foundress behaviour of a North American native wasp (Polistes fuscatus) versus an European invasive wasp (Polistes dominulus) were investigated in a controlled field experiment with optimal versus natural foraging conditions. Colonies with the optimal prey foraging conditions were provided with prey ad libitum within an enclosed area. The other colonies foraged in the adjacent field,woodland but had the same nest conditions as the other treatment. 2.,When given prey ad libitum, both wasp species captured similar amounts of prey and the conversion to total offspring biomass was similar. But P. dominulus colonies produced 2.5 times the number of workers as P. fuscatus colonies, reflecting the smaller size of P. dominulus wasps. 3.,Foundresses of P. dominulus were observed more often building or repairing the nest, thereby contributing to the production of colonies with twice as many cells as colonies of P. fuscatus. Foundresses of P. dominulus showed more acts of aggression toward workers than did P. fuscatus foundresses, which was not a function of adult density on the nest. 4.,At the end of the experiment, P. dominulus colonies with optimal prey foraging conditions still had a high level of egg-laying and peaked in the number of pupae then, whereas egg-laying and the number of pupae per colony of the other treatments began to decline 2,3 weeks earlier. These results indicate that P. dominulus is more opportunistic than P. fuscatus, which may account in part for P. dominulus's success as an introduced species in North America. [source]

    A review of competition in north temperate dung beetle communities

    John A. Finn
    Abstract. 1. Studies of north temperate dung beetle communities frequently invoke competition as an influential ecological process. In this review, the evidence for competition in north temperate dung beetle communities is evaluated and the role of competition as a factor affecting community structure is assessed. 2. Resource limitation and the evidence for interspecific competition are assessed by collating the available experimental and observational evidence for both the adult and larval stages of the dung beetle life cycle. The role of competition as a structuring force in dung beetle communities is discussed under the following headings: niche dynamics, migration to and from individual pats, the aggregation model of co-existence, and metapopulations. 3. Some of the main conclusions are that competition for space is much more likely to occur than competition for food; the effects of competition on community structure are poorly understood; several of the influential studies of competition in north temperate dung beetle communities need to be evaluated carefully. The differences in ecology between tropical and temperate dung beetle communities are clarified. 4. As priorities for future research, resource utilisation and competition should be researched experimentally: density-dependent relationships should be investigated, particularly for the larval stages, as should competitive interactions with other dung fauna. If such experimental approaches establish convincingly the occurrence of competition, then the extent of competition in the field and under real world conditions needs to be established. A functional group classification of dung beetles and other dung fauna is described, which may improve the generality of interpretation from individual, site-specific results. [source]

    The role of resources and natural enemies in determining the distribution of an insect herbivore population

    Iain S. Williams
    Summary 1. Both resources and natural enemies can influence the distribution of a herbivore. The ideal free distribution predicts that herbivores distribute themselves to optimise utilisation of resources. There is also evidence of herbivores seeking out refuges that reduce natural enemy attack (enemy-free space). Which of these theories predominates in a thistle,tephritid Terellia ruficauda (Diptera: Tephritidae),parasitoid interaction is examined. 2. The plant, Cirsium palustre, had a contagious distribution approximated by the negative binomial distribution. Terellia ruficauda foraged preferentially and oviposited on isolated plants although its larvae gained neither nutritional benefit nor reduced natural enemy pressure from such behaviour. 3. Parasitoids of T. ruficauda foraged and oviposited more frequently on isolated than on crowded T. ruficauda, resulting in inverse density-dependent parasitoid attack at all spatial scales examined. Neither the herbivore nor natural enemies distributed themselves according to the predictions of the ideal free distribution and the herbivore did not oviposit to reduce natural enemy attack. 4. Extrapolating from the theoretical predictions of the ideal free distribution and enemy-free space to the field requires considerable caution. Terellia ruficauda and its parasitoids appear to select their oviposition sites to spread the risk of losses through factors (e.g. mammal herbivory) that may damage dense clusters of C. palustre. [source]

    Insect colonisation sequences in bracts of Heliconia caribaea in Puerto Rico

    Barbara A. Richardson
    Summary 1. It was predicted that insects colonising Heliconia phytotelmata would exploit the different bract conditions along inflorescences, which result from sequential ageing. 2. Flowering of H. caribaea is asynchronous over a 6-month period. A method of identifying bracts of the same age, regardless of position on the inflorescence or inflorescence age, and from different plants over 2 years, was developed using comparative flowering phenology. 3. Heliconia insect larval communities were remarkably consistent from year to year in species composition and relative abundance. Occurrence within the plant population was also similar from year to year, and most species were Heliconia specific. 4. Significant interspecific differences were found in bract utilisation, with populations peaking at different stages of bract development. Ceratopogonid larvae were the earliest colonisers, followed by psychodids, syrphids, and culicids. Tipulids occurred much later in the cycle of bract development and ageing. These patterns were consistent in both years. 5. Patterns of bract utilisation provide strong support for temporal niche partitioning by variation in oviposition and development time. Communities were not considered to be structured by predation or pH changes along the bract sequence. [source]

    Conservation and utilisation: harnessing forces for better outcomes for native fishes

    John Koehn
    No abstract is available for this article. [source]

    Substrate choice of territorial male Topeka shiners (Notropis topeka) in the absence of sunfish (Lepomis sp.)

    C. C. Witte
    Abstract,,, Topeka shiners (Notropis topeka), an endangered minnow species, typically spawn on or around breeding Lepomis sunfish (Centrarchidae) nests. Why spawning Topeka shiners are attracted to these nests is unclear, but having the nesting sunfish provide shiner eggs with improved aeration, a lessening of siltation, and protection from egg predators are possibilities. We tested the substrate utilisation of Topeka shiners in outdoor tanks in the absence of sunfish to determine the shiner's fundamental choice. Shiners were provided with substrate patches of cleaned sand, small gravel, large gravel, and small cobble, and the bare floor of the tank. The substrate above which a male shiner established his territory was used as evidence of choice. A statistically significant choice for sand substrates was demonstrated. This fundamental choice might influence which sunfish nests Topeka shiners use, given that nest substrate characteristics differ both between sunfish species and within species by spawning site location. [source]

    Fourier Transformed Large Amplitude Square-Wave Voltammetry as an Alternative to Impedance Spectroscopy: Evaluation of Resistance, Capacitance and Electrode Kinetic Effects via an Heuristic Approach

    ELECTROANALYSIS, Issue 15-16 2005

    Abstract A detailed simulation of Fourier transformed large amplitude square-wave voltammetry is presented in the frequency domain for the process Red,Ox+e,. The simulation takes into account the influence of the electrode kinetics (Butler,Volmer model), uncompensated resistance (Ru) and double layer capacitance (Cdl). Of particular significance is the prediction that the even harmonic responses are only detected in the presence of quasi-reversibility or uncompensated resistance, and also are essentially devoid of charging current. In contrast, the DC and odd harmonic AC components exhibit much larger faradaic currents and also contain charging current. Conveniently, detailed analysis of the simulated DC and AC harmonic components reveals the presence of readily recognised patterns of behaviour with unique levels of sensitivity to electrode kinetics, Ru and Cdl, that facilitate quantitative analysis of these terms. These electrochemical parameters are generally calculated by small amplitude impedance spectroscopy and utilisation of linear analysis of equivalent circuits. Experimental studies on the one electron oxidation of ferrocene in dichloromethane (0.1,M Bu4NPF6) and the one electron reduction of [Fe(CN)6]3, in aqueous 0.5,M KCl electrolyte analysed via heuristic forms of data analysis based on recognition of patterns of behaviour, are presented as examples of a reversible process with significant uncompensated resistance and a quasi-reversible process with minimal ohmic drop, respectively. Results demonstrate the advantages of a more intuitively implemented form of data analysis than presently available with conventional forms of impedance spectroscopy. [source]

    Production of a Laccase and Decrease of the Phenolic Content in Canola Meal during the Growth of the Fungus Pleurotus ostreatus in Solid State Fermentation Processes

    J. Hu
    Abstract Solid state fermentation of canola meal was carried out with the fungus Pleurotus ostreatus DAOM 197961, which is a producer of laccase. The aim of this study was to examine the effects of moisture content, inoculum size, homogenisation of inoculum and particle size of canola meal on the growth of the fungus, the production of a laccase and the decrease of the content of sinapic acid esters (SAE) in a solid state process. The results showed that the optimum moisture content, which was varied in the media between 50% and 75%, for the growth and enzyme production was 60%. The initial rate of SAE content decrease was faster in the media with 70% and 75% moisture than in those with lower moisture levels. In the study of the effects of inoculum concentration in the range of 1.1 mg to 5.5 mg/g of the medium, it was found that larger amounts of biomass and enzyme were produced in the media with inoculum concentrations from 1.1 mg to 3.3 mg/g of the medium than in the media with a higher inoculum concentration. The final and approximately the same concentrations of SAE were reached at the same time regardless of the inoculum concentration. Considering that the fungus formed pellets under the conditions at which it was grown during the inoculum preparation, it was necessary to break them by homogenisation prior to their utilisation as an inoculum. The homogenisation was carried out during a period between 15s and 200s. Although higher biomass concentrations and enzyme activities were obtained in the media which were inoculated with the inoculum homogenised for 15s and 30s, the maximum enzyme activities and biomass concentrations were reached in the media inoculated with the inoculum, which was homogenised for 120s and 200s. The time of inoculum homogenisation did not influence the kinetics of the SAE decrease. When the effects of the particle size of canola meal on the process were studied, it was found that larger particles of the meal in the solid media were more favourable for the production of the biomass and enzyme, and for a faster decrease of the SAE content than those of smaller sizes. From the obtained results it can be concluded that the tested variables have a significant influence on the growth of the fungus Pleurotus ostreatus DAOM 197961, the production of laccase and the decrease of the SAE content in canola meal. The data could be useful for the development of a solid state process for the production of laccase and for the decrease of the phenolics content in canola meal. [source]