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Resource Use (resource + use)
Kinds of Resource Use Selected AbstractsResource Use and Survival of Patients Hospitalized With Congestive Heart Failure: Differences in Care by Specialty of the Attending PhysicianCONGESTIVE HEART FAILURE, Issue 2 2000David Tepper MD Editor No abstract is available for this article. [source] Predictors of Health Resource Use by Disabled Older Female Medicare Beneficiaries Living in the CommunityJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3 2003Michael Weiner MD OBJECTIVES: To identify specific clinical factors that could best predict resource use by disabled older women. DESIGN: Cross-sectional. SETTING: Urban community in Baltimore, Maryland. PARTICIPANTS: One thousand two community-dwelling, moderately to severely disabled, female Medicare beneficiaries aged 65 and older, from the Women's Health and Aging Study I (WHAS). MEASUREMENTS: WHAS data were merged with participants' 1992,1994 Medicare claims data for the year after baseline evaluation, reflecting inpatient, outpatient, home-based, and skilled-nursing services. The independent contributions of factors hypothesized to predict health expenditures were assessed, using chi-square and regression analyses, with the logarithm of Medicare expenditures as the primary outcome. RESULTS: Demographic factors were not associated with Medicare expenditures. Factors associated with expenditures in bivariate analyses included heart disease (1.4x), chronic obstructive pulmonary disease (1.3x), diabetes mellitus (1.1x), smoking, comorbidity, and severity of disability, as well as low creatinine clearance, serum albumin, caloric expenditure, or skinfold thickness. Heart disease, diabetes mellitus, and low skinfold thickness remained significant after adjustment for other factors. CONCLUSION: Heart disease, diabetes mellitus, and low skinfold thickness are important independent predictors of 1-year Medicare expenditures by disabled older women. Many other variables that reflect disease, disability, nutrition, or personal habits have less predictive ability. Most demographic factors are not predictors of expenditures in this population. Focusing on the best predictors may facilitate more-effective risk adjustment and creation of related health policies. [source] Validation of Length of Hospital Stay as a Surrogate Measure for Injury Severity and Resource Use Among Injury SurvivorsACADEMIC EMERGENCY MEDICINE, Issue 2 2010Craig D. Newgard MD Abstract Objectives:, While hospital length of stay (LOS) has been used as a surrogate injury outcome when more detailed outcomes are unavailable, it has not been validated. This project sought to validate LOS as a proxy measure of injury severity and resource use in heterogeneous injury populations. Methods:, This observational study used four retrospective cohorts: patients presenting to 339 California emergency departments (EDs) with a primary International Classification of Diseases, Ninth Revision (ICD-9), injury diagnosis (years 2005,2006); California hospital injury admissions (a subset of the ED population); trauma patients presenting to 48 Oregon EDs (years 1998,2003); and injured Medicare patients admitted to 171 Oregon and Washington hospitals (years 2001,2002). In-hospital deaths were excluded, as they represent adverse outcomes regardless of LOS. Duration of hospital stay was defined as the number of days from ED admission to hospital discharge. The primary composite outcome (dichotomous) was serious injury (Injury Severity Score [ISS] , 16 or ICD-9 ISS , 0.90) or resource use (major surgery, blood transfusion, or prolonged ventilation). The discriminatory accuracy of LOS for identifying the composite outcome was evaluated using receiver operating characteristic (ROC) analysis. Analyses were also stratified by age (0,14, 15,64, and ,65 years), hospital type, and hospital annual admission volume. Results:, The four cohorts included 3,989,409 California ED injury visits (including admissions), 236,639 California injury admissions, 23,817 Oregon trauma patients, and 30,804 Medicare injury admissions. Composite outcome rates for the four cohorts were 2.1%, 29%, 27%, and 22%, respectively. Areas under the ROC curves for overall LOS were 0.88 (California ED), 0.74 (California admissions), 0.82 (Oregon trauma patients), and 0.68 (Medicare patients). In general, the discriminatory value of LOS was highest among children, tertiary trauma centers, and higher volume hospitals, although this finding differed by the injury population and outcome assessed. Conclusions:, Hospital LOS may be a reasonable proxy for serious injury and resource use among injury survivors when more detailed outcomes are unavailable, although the discriminatory value differs by age and the injury population being studied. ACADEMIC EMERGENCY MEDICINE 2010; 17:142,150 © 2010 by the Society for Academic Emergency Medicine [source] Sustainable Resource Use in the Asia-Pacific RegionJOURNAL OF INDUSTRIAL ECOLOGY, Issue 4 2010A Major Policy Challenge First page of article [source] Efficient Resource Use in Simplified Complete Denture FabricationJOURNAL OF PROSTHODONTICS, Issue 7 2010MMedSci, Yasuhiko Kawai DDS Abstract Purpose: Conventional dentures will remain the only treatment available to most edentulous people for the foreseeable future. In this study, we compared the efficiency of two methods of making complete conventional dentures,the traditional academic standard (T) and a simplified technique (S) used in private practice. We have previously shown that they produce similar levels of patient satisfaction and denture quality. Materials and Methods: Data were gathered during a randomized controlled clinical trial of 122 subjects from initial examination until 6-month follow-up. For this report, the direct costs of providing one set of conventional complete dentures by T or S techniques were estimated. All materials used were recorded and their cost was calculated in Canadian dollars (CAN$). The costs of fabrication in an outside laboratory were added. Clinician's labor time was recorded for every procedure. Between-group comparisons for each clinical procedure were carried out with independent t -tests. The number of patients in each group who needed postdelivery treatment was compared with Chi-square tests. The effect of group assignment and of treatment difficulty on outcomes was analyzed with multiple regression analysis. Results: The mean total cost of the T method was significantly greater than S (CAN$166.3; p < 0.001), and clinicians spent 90 minutes longer (p < 0.001) on clinical care. The difficulty of the case had no significant influence on outcomes. Conclusions: The results indicate that the S method is the more cost-efficient method and that there are no negative consequences that detract from the cost savings. [source] Resource Use and Cost of Diagnostic Workup of Women with Suspected Breast CancerTHE BREAST JOURNAL, Issue 1 2009David W. Lee PhD Abstract:, We estimated resource use and costs associated with a diagnostic workup for suspected breast cancer among Medicare beneficiaries. Using Medicare claims data, we found that the average cost of a diagnostic workup for suspected breast cancer,whether it eventuated in a breast cancer diagnosis or not,was $361, and did not vary by presentation (signs/symptoms or screening mammography). In the aggregate, we estimate that Medicare spends approximately $679 million annually on diagnostic workups for women with suspected breast cancer, and that false positive mammograms result in diagnostic costs of approximately $250 million. [source] Rural-Urban Differences in Health Risks, Resource Use and Expenditures Within Three State Medicaid Programs: Implications for Medicaid Managed CareTHE JOURNAL OF RURAL HEALTH, Issue 1 2002Janet M. Bronstein Ph.D. This study uses Medicaid claims data for income-eligible enrollees in California, Georgia and Mississippi to compare expenditures, resource usage and health risks between residents of rural and urban areas of the states. Resource use is measured using the Resource Based Relative Value Scale (RBRVS) system for professional services, hospital days and outpatient facility visits; it also is valued at private insurance reimbursement rates for the states. Health risks are measured using the diagnosis-based Adjusted Clinical Group system. Resource use is compared on a risk-adjusted basis with the use of urban Medicaid enrollees as the benchmark. We find that actual expenditures for rural care users are lower than for urban care users. However, because the proportion of Medicaid enrollees who use care is higher in rural than in urban areas in all three states, expenditures per rural enrollee are not consistently lower. Case mix is more resource intensive for rural compared to urban residents in all three states. Although resource usage is not systematically lower owerall for rural enrollees, on a risk-adjusted basis they tend to use less hospital resources than urban enrollees. Capitation rates based on historical per enrollee expenditures would not appear to under-reimburse managed care organizations for the care of rural as opposed to urban residents in the study states. [source] The economic costs of dementia in Korea, 2002INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2006Guk-Hee Suh Abstract Objective To estimate the economic costs of dementia in 2002 using an economic evaluation model for dementia care. Methods Data were from the Korea National Survey of the Long-Term Care Need (LTC survey) (n,=,5058), two prospective 1-year studies [one clinical trial (n,=,234), one naturalistic community cohort study (n,=,107)], and two epidemiologic community studies for prevalence of dementia (n,=,1037,+,1481). Daily costs and proportions of different levels of institutional service provided were collected from the LTC survey. Resource use in the community included health care services, social care services, out-of-pocket purchase for self-support, caregiver time and missed work of caregiver. Costs in community were calculated based on resource utilization multiplied by the unit costs for each resource. Results Total annual costs of dementia were estimated to be over 2.4 billion US$ for 272,000 dementia sufferers. Costs in community represent 96% of the total annual costs, while costs of informal care and missed work of caregivers were 1.3 billion US$, or 55% of total annual cost. Average annual costs of full time care (FTC) and pre-FTC in community LTC were 44,121 US$ and 13,273 US$ per person, whereas cost per patient who did not need community LTC was 3986 US$. Conclusion Given that the number of dementia sufferers is projected to increase in the near future and that larger part of the costs are subsidized by the government, the economic and social costs of dementia is significant not only for dementia sufferers and their caregivers, but also for society. Copyright © 2006 John Wiley & Sons, Ltd. [source] An economic evaluation of NIOX MINO airway inflammation monitor in the United KingdomALLERGY, Issue 3 2009D. Price Background:, Fractional exhaled nitric oxide (FENO), a marker of eosinophilic airway inflammation, is easily measured by noninvasive means. The objective of this study was to determine the cost-effectiveness of FENO measurement using a hand-held monitor (NIOX MINO), at a reimbursement price of £23, for asthma diagnosis and management in the UK. Methods:, We constructed two decision trees to compare FENO measurement with standard diagnostic testing and guideline recommendations for management. For asthma diagnosis, we compared FENO measurement with lung function and reversibility testing, bronchial provocation and sputum eosinophil count. For asthma management, we evaluated the impact on asthma control, including inhaled corticosteroid use, exacerbations and hospitalizations, of monitoring with FENO measurement vs symptoms and lung function as in standard care. Resource use and health outcomes were evaluated over a 1-year time frame. Direct costs were calculated from a UK health-care payer perspective (2005 £). Results:, An asthma diagnosis using FENO measurement cost £43 less per patient as compared with standard diagnostic tests. Asthma management using FENO measurement instead of lung function testing resulted in annual cost-savings of £341 and 0.06 quality-adjusted life-years gained for patients with mild to severe asthma and cost-savings of £554 and 0.004 quality-adjusted life-years gained for those with moderate to severe asthma. Conclusions:, Asthma diagnosis based on FENO measurement with NIOX MINO alone is less costly and more accurate than standard diagnostic methods. Asthma management based on FENO measurement is less costly than asthma management based on standard guidelines and provides similar health benefits. [source] Resource use and costs in a Swedish cohort of patients with Parkinson's diseaseMOVEMENT DISORDERS, Issue 6 2002Peter Hagell RN Abstract We estimated resource use and costs in patients with Parkinson's disease (PD), thereby providing baseline data for future economic evaluations of therapeutic interventions. Data were collected from medical records of a South Swedish cohort of 127 PD patients during 1 year (1996) and a mailed questionnaire inquiring about cost-related consequences and resource use in 1996 and in 2000. Annual costs were calculated based on prevalence and expressed in SEK (monetary value of the year 2000). Direct health care costs averaged approximately SEK 29,000 (,USD 2,900; EUR 3,200) per patient per year, of which drugs were the most costly component. Nonmedical direct costs were higher than direct health care costs, averaging approximately SEK 43,000 (,USD 4,300; EUR 4,800) per patient per year, and costs due to lost production were approximately SEK 52,000 (,USD 5,200; EUR 5,800) per patient per year. The mean total annual cost for PD in our sample approximated SEK 124,000 (,USD 12,400; EUR 13,800) per patient. These findings are roughly within the same range as estimates from other countries and show that PD causes a considerable societal burden. In addition to other outcomes, evaluations of the economic implications of new therapeutic interventions are highly warranted. In this perspective, the present study provides valuable baseline data. © 2002 Movement Disorder Society [source] Spatial and temporal partitioning of behaviour by adult dacines: direct evidence for methyl eugenol as a mate rendezvous cue for Bactrocera cacuminataPHYSIOLOGICAL ENTOMOLOGY, Issue 3 2003S. Raghu Abstract., Resource use in adult Dacinae (Diptera: Tephritidae) is believed to be restricted to the host plant (i.e. the plant that provides fruit for oviposition and larval development). However, studies on Bactrocera cacuminata did not support this hypothesis. Thus, it was hypothesized that adult flies partition their diurnal activities between spatially separated resources (host plant, sugar, protein and methyl eugenol) as a function of the physiological status of the fly (immature, mature,unmated, mature,mated). In accordance with a priori predictions, the results of a field-cage study show that there are significant diurnal patterns in abundance and behaviour, and that flies of different physiological status use resources differently. Immature flies spend most of their time foraging for sugar and protein to facilitate development. Sexually mature flies forage for sugars during the day, and at dusk, responded strongly to methyl eugenol and mate. The fact that polygynous males wait at methyl eugenol at dusk whereas the mated, monandrous females spend their time ovipositing in fruit and are nonresponsive to methyl eugenol, supports Metcalf's hypothesis that such phenylpropanoids serve as mate rendezvous cues. [source] Rural-Urban Differences in Health Risks, Resource Use and Expenditures Within Three State Medicaid Programs: Implications for Medicaid Managed CareTHE JOURNAL OF RURAL HEALTH, Issue 1 2002Janet M. Bronstein Ph.D. This study uses Medicaid claims data for income-eligible enrollees in California, Georgia and Mississippi to compare expenditures, resource usage and health risks between residents of rural and urban areas of the states. Resource use is measured using the Resource Based Relative Value Scale (RBRVS) system for professional services, hospital days and outpatient facility visits; it also is valued at private insurance reimbursement rates for the states. Health risks are measured using the diagnosis-based Adjusted Clinical Group system. Resource use is compared on a risk-adjusted basis with the use of urban Medicaid enrollees as the benchmark. We find that actual expenditures for rural care users are lower than for urban care users. However, because the proportion of Medicaid enrollees who use care is higher in rural than in urban areas in all three states, expenditures per rural enrollee are not consistently lower. Case mix is more resource intensive for rural compared to urban residents in all three states. Although resource usage is not systematically lower owerall for rural enrollees, on a risk-adjusted basis they tend to use less hospital resources than urban enrollees. Capitation rates based on historical per enrollee expenditures would not appear to under-reimburse managed care organizations for the care of rural as opposed to urban residents in the study states. [source] Area-Based Refinement for Selection of Reserve Sites with the Benefit-Function ApproachCONSERVATION BIOLOGY, Issue 2 2007ANNI ARPONEN algoritmo de selección de sitios; persistencia; peso de especies; relaciones especies-área; selección de reservas Abstract:,Optimization of resource use is necessary for efficient conservation planning. Many reserve-selection algorithms aim to identify representative but inexpensive networks, which may lead to selecting small sites due to their lower costs and collectively higher species richness. Nevertheless, larger sites would be preferable regarding species' long-term persistence. An area-based refinement can be used to overcome this problem. We used a reserve-planning framework in which continuous benefit functions valued representation (numbers of populations), and differential species weights were based on a species' local rarity and threatened status. We introduced a refinement based on the species-area relationship that provides relatively higher values for larger sites. We applied the proposed method to rich fen vegetation in southern Finland. The species-area refinement resulted in a network of significantly larger sites with minor trade-offs with representation (numbers of populations). Giving endangered species higher weights ensured that the trade-off occurred mostly between site size and representation of low-priority species. We recommend using a species-area refinement for practical, maximum-coverage conservation planning. Resumen:,La optimización del uso de recursos es necesaria para la planificación eficiente de la conservación. Muchos algoritmos para la selección de reservas tratan de identificar redes representativas pero poco costosas, que pueden conducir a la selección de sitios pequeños debido a sus costos menores y mayor riqueza de especies colectiva. Sin embargo, los sitios grandes serían preferibles para la persistencia de las especies a largo plazo. Para sobreponerse a este problema se puede utilizar un refinamiento basado en el área. Utilizamos un marco de referencia para la planificación de reservas en el que las funciones de beneficio continuas valoraron la representación (número de poblaciones), y los pesos diferenciales de las especies se basaron en la rareza local de una especie y en su estatus de amenaza. Introdujimos un refinamiento basado en la relación especies-área que proporciona valores relativamente mayores a los sitios grandes. Aplicamos el método propuesto a la rica vegetación de ciénegas en el sur de Finlandia. El refinamiento de las especies-área resultó en una red de sitios significativamente más grandes con desequilibrios menores en la representación (número de poblaciones). La asignación de valores más altos a las especies en peligro aseguró que el desequilibrio ocurriera principalmente entre el tamaño del sitio y la representación de especies de prioridad baja. Recomendamos la utilización de de un refinamiento de especies-área para una planificación de la conservación de cobertura máxima. [source] Conservation Alliances with Indigenous Peoples of the AmazonCONSERVATION BIOLOGY, Issue 3 2005STEPHAN SCHWARTZMAN The future of Amazonian indigenous reserves is of strategic importance for the fate of biodiversity in the region. We examined the legislation governing resource use on indigenous lands and summarize the history of the Kayapo people's consolidation of their >100,000 km2 territory. Like many Amazonian indigenous peoples, the Kayapo have halted the expansion of the agricultural frontier on their lands but allow selective logging and gold mining. Prospects for long-term conservation and sustainability in these lands depend on indigenous peoples' understandings of their resource base and on available economic alternatives. Although forest conservation is not guaranteed by either tenure security or indigenous knowledge, indigenous societies' relatively egalitarian common-property resource management regimes,along with adequate incentives and long-term partnerships with conservation organizations,can achieve this result. Successful initiatives include Conservation International's long-term project with the A'ukre Kayapo village and incipient large-scale territorial monitoring and control in the Kayapo territory, and the Instituto SocioAmbiental (ISA) 15-year partnership with the peoples of the Xingu Indigenous Park, with projects centered on territorial monitoring and control, education, community organization, and economic alternatives. The recent agreement on ecological restoration of the Xingu River headwaters between ranchers and private companies, indigenous peoples, and environmentalists, brokered by ISA, marks the emergence of an indigenous and conservation alliance of sufficient cohesiveness and legitimacy to negotiate effectively at a regional scale. Resumen:,Las alianzas actuales entre indígenas y organizaciones de conservación en el Amazonas Brasileño han ayudado a obtener el reconocimiento oficial de ,1 millón de km2 en áreas indígenas. El futuro del as reservas indígenas amazónicas es de importancia estratégica para el futuro de la biodiversidad en la región. Examinamos la legislación que rige a la utilización de recursos en zonas indígenas y sintetizamos la historia de la consolidación del territorio > 100,000 km2 de la etnia Kayapo. Como muchos grupos Amazónicos, los Kayapo han detenido la expansión de la frontera agrícola en sus tierras pero permiten actividades madereras y mineras selectivas. Las perspectivas de conservación y sustentabilidad a largo plazo en estas tierras dependen del entendimiento de su base de recursos y de las alternativas económicas disponibles por parte de los grupos indígenas. A pesar de que ni la seguridad en la posesión ni el conocimiento indígena garantizan la conservación de los bosques, los regímenes indígenas de gestión de recursos de propiedad común relativamente igualitarios en conjunto con incentivos adecuados y asociaciones con organizaciones de conservación pueden obtener este resultado. Iniciativas exitosas incluyen el proyecto a largo plazo de Conservation International con el pueblo A'ukre Kayapo y el incipiente monitoreo y control territorial a gran escala en el territorio Kayapo y la asociación durante 15 años del Instituto Socioambiental (ISA) con habitantes del Parque Indígena Xingu, con proyectos enfocados al monitoreo y control territorial, a la educación, a la organización comunitaria y a alternativas económicas. El reciente acuerdo, negociado por ISA, entre rancheros y compañías privadas, grupos indígenas y ambientalistas para la restauración ecológica del Río Xingu marca el surgimiento de una alianza indígena y de conservación con la cohesión y legitimidad suficientes para negociar efectivamente a escala regional. [source] Empowering Pyromaniacs in Madagascar: Ideology and Legitimacy in Community-Based Natural Resource ManagementDEVELOPMENT AND CHANGE, Issue 1 2002Christian A. Kull Development practitioners frequently rely on community-based natural resource management (CBNRM) as an approach to encourage equitable and sustainable environmental resource use. Based on an analysis of the case of grassland and woodland burning in highland Madagascar, this article argues that the success of CBNRM depends upon the real empowerment of local resource users and attention to legitimacy in local institutions. Two key factors , obstructive environmental ideologies (,received wisdoms') and the complex political and social arena of ,community' governance , challenge empowerment and legitimacy and can transform outcomes. In Madagascar, persistent hesitancy among leaders over the legitimate role of fire has sidetracked a new CBNRM policy called GELOSE away from one of its original purposes , community fire management , towards other applications, such as community management of forest exploitation. In addition, complications with local governance frustrate implementation efforts. As a result, a century-long political stalemate over fire continues. [source] Risperidone long-acting injection: a 6-year mirror-image study of healthcare resource useACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2009D. Taylor Objective:, To evaluate naturalistic use of risperidone long-acting injection (RLAI) and its effect on healthcare resource use. Method:, Mirror-image comparison of healthcare resource use for 3 years before RLAI initiation and 3 years after. Results:, In total, 211 of 277 patients consecutively prescribed RLAI were evaluable over the full 6-year study period. Median days in hospital/patient increased significantly in the 3 years after RLAI initiation [87 days (inter-quartile range 25,236) before vs. 192 days (47,426) after; P < 0.001]. Those 34 patients who continued RLAI for 3 years showed no change in median bed days [64 days (6.5,182) before vs. 64 days (12,180) after] and median number of admissions was decreased [1.5 (1,2.25) before vs. 1.00 (0,1.25) after; P = 0.001]. Healthcare costs more than doubled for the whole cohort (P < 0.001) and discontinuers (P < 0.001) and increased significantly for continuers (P = 0.010). Conclusion:, RLAI did not decrease either time spent in hospital or overall healthcare costs in this patient cohort. [source] A System for Grouping Presenting Complaints: The Pediatric Emergency Reason for Visit ClustersACADEMIC EMERGENCY MEDICINE, Issue 8 2005MSCE, Marc H. Gorelick MD Abstract Objectives: To develop a set of chief complaint groupings for pediatric emergency department (ED) visits that is comprehensive, parsimonious, clinically sensible, and evidence-based. Methods: Investigators derived candidate chief complaint clusters and ranked them a priori into three perceived severity categories. Pediatric visits were extracted from the National Hospital Ambulatory Medical Care Survey (NHAMCS); data for years 1998 and 2000 (n= 13,186) were used for derivation and data for year 1999 (n= 5,365) were used for validation. Visits were assigned to clusters based on the recorded complaints; clusters were combined to ensure adequate numbers for analysis (minimum n= 20), and the clusters were reviewed for clinical sensibility. Resource utilization was categorized in three levels: routine (examination only), ED treatment (tests or therapy in the ED but not admitted), and admission. Area under the receiver-operating characteristic (ROC) curve (AUC) was used to demonstrate the discriminative ability of the clusters in predicting resource use. Results: There were 463 unique complaints in the derivation database; 95 (20%) had a single associated visit. Fifty-two clusters were generated; only 2.4% of complaints were classified as other. The eight most common clusters encompassed 52% of the visits. The top five were fever (11%), extremity pain/injury, vomiting, cough, and trauma (unspecified). Complaint clusters were associated with actual resource utilization: for routine care, the AUC was 0.73 (0.74 in the validation set), and for admission, the AUC was 0.77 (0.74 in the validation set). Both resource utilization and triage classification increased with increased expert severity ranking (test for trend, p < 0.001). Conclusions: The proposed Pediatric Emergency Reason for Visit Cluster (PERC) system is a comprehensive yet parsimonious, clinically sensible means of categorizing pediatric ED complaints. The PERC system's association with measures of acuity and resource utilization makes it a potentially useful tool in epidemiologic and health services research. [source] Using neutral landscapes to identify patterns of aggregation across resource pointsECOGRAPHY, Issue 3 2006Jill Lancaster Many organisms are aggregated within resource patches and aggregated spatially across landscapes with multiple resources. Such patchy distributions underpin models of population regulation and species coexistence, so ecologists require methods to analyse spatially-explicit data of resource distribution and use. I describe a method for analysing maps of resources and testing hypotheses about how resource distribution influences the distribution of organisms, where resource patches can be described as points in a landscape and the number of organisms on each resource point is known. Using a mark correlation function and the linearised form of Ripley's K-function, this version of marked point pattern analysis can characterise and test hypotheses about the spatial distribution of organisms (marks) on resource patches (points). The method extends a version of point pattern analysis that has wide ecological applicability, it can describe patterns over a range of scales, and can detect mixed patterns. Statistically, Monte Carlo permutations are used to estimate the difference between the observed and expected values of the mark correlation function. Hypothesis testing employs a flexible neutral landscape approach in which spatial characteristics of point patterns are preserved to some extent, and marks are randomised across points. I describe the steps required to identify the appropriate neutral landscape and apply the analysis. Simulated data sets illustrate how the choice of neutral landscape can influence ecological interpretations, and how this spatially-explicit method and traditional dispersion indices can yield different interpretations. Interpretations may be general or context-sensitive, depending on information available about the underlying point pattern and the neutral landscape. An empirical example of caterpillars exploiting food plants illustrates how this technique might be used to test hypotheses about adult oviposition and larval dispersal. This approach can increase the value of survey data, by making it possible to quantify the distribution of resource points in the landscape and the pattern of resource use by species. [source] Survival, movement, and resource use of the butterfly Parnassius clodiusECOLOGICAL ENTOMOLOGY, Issue 2 2004Julia N. Auckland Abstract., 1. A mark,recapture study was conducted on the American Apollo butterfly Parnassius clodius Menetries during three field seasons (1998,2000) to examine its movement patterns over the course of a season within a sagebrush meadow in Grand Teton National Park, Wyoming, U.S.A. The study examined how resources affected butterfly distribution patterns and used mark,recapture data to gain insight into movement differences between sexes and over time. 2. The average straight-line movement of P. clodius was 202 m day,1, adjusted for sampling effort at different distances. Movement estimates in all 3 years were highly correlated with the average distance between plots sampled. 3. Butterfly abundance was correlated positively with per cent cover of its host plant Dicentra uniflora, but this relationship decreased in importance during the peak of the flight period when individuals may be more interested in finding mates. There was a weak, positive correlation between butterfly abundance and the abundance of its primary nectar source, Eriogonum umbellatum in 1999, but no relationship in 2000. 4. Survival, recapture, and transition probabilities were estimated using open population, capture,recapture models. Survival and recapture probability decreased over the course of each season, while the probability of moving between plots increased. Recapture probability was significantly lower for females than for males among all 3 years, but there was no difference between the sexes in survival rate. [source] Host plants and butterfly biology.ECOLOGICAL ENTOMOLOGY, Issue 1 2004Do host-plant strategies drive butterfly status? Abstract., 1.,To determine whether rarity and decline is linked to organism ecology, associations have been examined between butterfly larval host-plant competitive, stress-tolerant, ruderal (C-S-R) strategies and butterfly biology. 2.,Associations have been sought between mean C-S-R scores for larval host plants with butterfly life history, morphology and physiology variables, resource use, population attributes, geography, and conservation status. Comparisons are carried out across species and controlled for phylogenetic patterning. 3.,Butterfly biology is linked to host-plant strategies. An increasing tendency of a butterfly's host plants to a particular strategy biases that butterfly species to functionally linked life-history attributes and resource breadth and type. In turn, population attributes and geography are significantly and substantially affected by host choice and the strategies of these host plants. 4.,The greatest contrast is between butterfly species whose host plants are labelled C and R strategists and those whose host plants are labelled S strategists. Increasingly high host-plant C and R strategy scores bias butterflies to rapid development, short early stages, multivoltinism, long flight periods, early seasonal emergence, higher mobility, polyphagy, wide resource availability and biotope occupancy, open, areally expansive, patchy population structures, denser distributions, wider geographical ranges, resistance to range retractions as well as to increasing rarity in the face of environmental changes. Increasing host-plant S strategy scores have reversed tendencies, biasing those butterfly species to extended development times, fewer broods, short flight periods, smaller wing expanse and lower mobility, monophagy, restricted resource exploitation and biotope occupancy, closed, areally limited populations with typical metapopulation structures, sparse distributions, and limited geographical ranges, range retractions, and increased rarity. 5.,Species with S strategy host plants are species vulnerable to current environmental changes and species of conservation concern. [source] Taking species abundance distributions beyond individualsECOLOGY LETTERS, Issue 6 2009Hélène Morlon Abstract The species abundance distribution (SAD) is one of the few universal patterns in ecology. Research on this fundamental distribution has primarily focused on the study of numerical counts, irrespective of the traits of individuals. Here we show that considering a set of Generalized Species Abundance Distributions (GSADs) encompassing several abundance measures, such as numerical abundance, biomass and resource use, can provide novel insights into the structure of ecological communities and the forces that organize them. We use a taxonomically diverse combination of macroecological data sets to investigate the similarities and differences between GSADs. We then use probability theory to explore, under parsimonious assumptions, theoretical linkages among them. Our study suggests that examining different GSADs simultaneously in natural systems may help with assessing determinants of community structure. Broadening SADs to encompass multiple abundance measures opens novel perspectives in biodiversity research and warrants future empirical and theoretical developments. [source] Minimizing energy expenditure facilitates vertebrate persistence on oceanic islandsECOLOGY LETTERS, Issue 5 2002Brian K. McNab Abstract The characteristics of terrestrial vertebrates on oceanic islands are examined. They often include a reduced body size, a tolerance of conspecifics, flightlessness, a reduced basal rate of metabolism, and a propensity to enter torpor. On oceanic islands ectotherms frequently replace endotherms. These changes reduce the energy expenditure and resource requirements of vertebrates. Such reductions are permitted by the absence of mammalian predators and facilitate the survival of island endemics in the face of a restricted resource base and a variable environment through an increase in population size. Some insular species increase body size, but this occurs only when the resource base is large, due either to a fortuitously abundant resource, or to the absence of other species that exploit normally abundant resources. Some questions are posed to guide future work. They examine of the characteristics that permit species to disperse over water barriers, the conditions that require a reduction in resource use, the rapidity of response by immigrants to island conditions, whether supertramps show physiological differentiation with respect to island distance or size, and whether island size is absolute or relative to the size of the immigrants. [source] Atlantic salmon Salmo salar L., brown trout Salmo trutta L. and Arctic charr Salvelinus alpinus (L.): a review of aspects of their life historiesECOLOGY OF FRESHWATER FISH, Issue 1 2003A. Klemetsen Abstract ,,,Among the species in the family Salmonidae, those represented by the genera Salmo, Salvelinus, and Oncorhynchus (subfamily Salmoninae) are the most studied. Here, various aspects of phenotypic and life-history variation of Atlantic salmon Salmo salar L., brown trout Salmo trutta L., and Arctic charr Salvelinus alpinus (L.) are reviewed. While many strategies and tactics are commonly used by these species, there are also differences in their ecology and population dynamics that result in a variety of interesting and diverse topics that are challenging for future research. Atlantic salmon display considerable phenotypic plasticity and variability in life-history characters ranging from fully freshwater resident forms, where females can mature at approximately 10 cm in length, to anadromous populations characterised by 3,5 sea-winter (5SW) salmon. Even within simple 1SW populations, 20 or more spawning life-history types can be identified. Juveniles in freshwater can use both fluvial and lacustrine habitats for rearing, and while most smolts migrate to sea during the spring, fall migrations occur in some populations. At sea, some salmon undertake extensive oceanic migrations while other populations stay within the geographical confines of areas such as the Baltic Sea. At the other extreme are those that reside in estuaries and return to freshwater to spawn after spending only a few months at sea. The review of information on the diversity of life-history forms is related to conservation aspects associated with Atlantic salmon populations and current trends in abundance and survival. Brown trout is indigenous to Europe, North Africa and western Asia, but was introduced into at least 24 countries outside Europe and now has a world-wide distribution. It exploits both fresh and salt waters for feeding and spawning (brackish), and populations are often partially migratory. One part of the population leaves and feeds elsewhere, while another part stays as residents. In large, complex systems, the species is polymorphic with different size morphs in the various parts of the habitat. Brown trout feed close to the surface and near shore, but large individuals may move far offshore. The species exhibits ontogenetic niche shifts partly related to size and partly to developmental rate. They switch when the amount of surplus energy available for growth becomes small with fast growers being younger and smaller fish than slow growers. Brown trout is an opportunistic carnivore, but individuals specialise at least temporarily on particular food items; insect larvae are important for the young in streams, while littoral epibenthos in lakes and fish are most important for large trout. The sexes differ in resource use and size. Females are more inclined than males to become migratory and feed in pelagic waters. Males exploit running water, near-shore and surface waters more than females. Therefore, females feed more on zooplankton and exhibit a more uniform phenotype than males. The Arctic charr is the northernmost freshwater fish on earth, with a circumpolar distribution in the Holarctic that matches the last glaciation. Recent mtDNA studies indicate that there are five phylogeographic lineages (Atlantic, Arctic, Bering, Siberian and Acadian) that may be of Pleistocene origin. Phenotypic expression and ecology are more variable in charr than in most fish. Weights at maturation range from 3 g to 12 kg. Population differences in morphology and coloration are large and can have some genetic basis. Charr live in streams, at sea and in all habitats of oligotrophic lakes, including very deep areas. Ontogenetic habitat shifts between lacustrine habitats are common. The charr feed on all major prey types of streams, lakes and near-shore marine habitats, but has high niche flexibility in competition. Cannibalism is expressed in several cases, and can be important for developing and maintaining bimodal size distributions. Anadromy is found in the northern part of its range and involves about 40, but sometimes more days in the sea. All charr overwinter in freshwater. Partial migration is common, but the degree of anadromy varies greatly among populations. The food at sea includes zooplankton and pelagic fish, but also epibenthos. Polymorphism and sympatric morphs are much studied. As a prominent fish of glaciated lakes, charr is an important species for studying ecological speciation by the combination of field studies and experiments, particularly in the fields of morphometric heterochrony and comparative behaviour. [source] The Paradoxes of Environmental Policy and Resource Management in Reform-Era China,ECONOMIC GEOGRAPHY, Issue 3 2000Joshua Muldavin Abstract: Over the last 5,000 years serious environmental problems,deforestation, desertification, erosion, and widespread pollution of air, land, and water,have prevailed throughout most of China, brought about by a diverse set of social and political contexts. In this paper I focus on an enduring contradiction associated with the post-1978 reforms, namely accelerated environmental resource degradation in rural areas amid unprecedented national economic growth. Declining entitlements to assets and social capital in China's rural village populations are a crucial aspect of altered state-peasant relations, as these are increasingly mediated by the market during China's transition to a hybrid economy. This has resulted in changing patterns of resource use, impacting both the environment and peasant livelihoods. A brief assessment of China's postrevolutionary environmental policy and management practices provides the context for detailed case studies in Henan Province. These examples highlight the relationship between political-economic changes and environmental policy and management. Contrary to reform rhetoric, rural peasants' embracing of reform policies does not necessarily optimize their welfare or promote sustainable use of resources. The case studies reveal alternative pathways for villages, ones that ought to be brought into the policy debate spotlight. [source] Cost-effectiveness of pharmacy and group behavioural support smoking cessation services in GlasgowADDICTION, Issue 2 2009Kathleen A. Boyd ABSTRACT Aims Smokers attending group-based support for smoking cessation in Glasgow are significantly more likely to be successful than those attending pharmacy-based support. This study examined the cost-effectiveness of these two modes of support. Design Combination of observational study data and information from National Health Service (NHS) Greater Glasgow and Clyde smoking cessation services. Setting Glasgow, Scotland. Participants A total of 1979 smokers who accessed either of the cessation services between March and May 2007. Intervention Two smoking treatment services offering one-to-one support in pharmacies, and providing group counselling in the community. Measurements Routine monitoring data on resource use and smoking status (carbon monoxide-validated, self-reported, non-quitters and relapsers) at 4-week follow-up. Findings The incremental cost per 4-week quitter for pharmacy support was found to be approximately £772, and £1612 for group support, in comparison to self-quit cessation attempts. These findings compare favourably with previously published outcomes from cost-effectiveness smoking cessation studies. Assuming a relapse rate of 75% from 4 weeks to 1 year and a further 35% beyond 1 year, and combining this with an average of 1.98 quality adjusted life years (QALY) gained per permanent cessation, provides an estimated incremental cost per QALY of £4400 for the pharmacy service and £5400 for group support service. Conclusions Group support and pharmacy-based support for smoking cessation are both extremely cost-effective. [source] Maximizing resource recovery from waste streamsENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 4 2003Tim Grant Resource conservation and waste management have become two sides of the same argument. According to the Institutefor Local Self Reliance in the US., the recycling revolution begun in the l960s was a reaction "to the levels of waste in our economy and the pollution and suffering these habits cause worldwide" [1,2]. However, the recycling targetsetting of the early 1990s was focused on diversion from landfill, and it has taken another 10 years for the focus to shift back to the resource values approach, driven largely by the application of Life Cycle Assessment to the waste management system. This paper examines materials in the waste stream to determine the "value proposition" in each material group, and to examine options for efficient resource use and recovery. Specifically, it discusses waste management issues associated with clean fill, food waste, timber waste, concrete and bricks, green waste, paper and board, metals, plastics, and glass. [source] Endocrine responses of Fundulus heteroclitus to effluent from a bleached-kraft pulp mill before and after installation of reverse osmosis treatment of a waste streamENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2000Monique G. Dubé Abstract Implementation of process changes on the nonbleaching side of bleached kraft pulp mill (BKPM) operations has increased in recent years to maximize resource use and to minimize residual environmental effects of discharged effluents. The objective of this study was to determine if reverse osmosis (RO) treatment of evaporator and digester clean condensates reduced or removed the effects of a BKPM effluent on reproductive endocrine function of the estuarine killifish, Fundulus heteroclitus (mummichog). Comparison of data collected before (1997) and after (1998), the years of the process change, showed that the potential of the combined mill effluent to depress plasma testosterone levels after 30 and 57 d of exposure to an environmentally relevant effluent concentration (1%) was reduced after RO treatment of condensates. However, in vitro production of some sex steroids was depressed with a 1% effluent exposure after the process change. In addition, in 1998, depression of plasma testosterone levels in effluent-exposed fish was present at higher effluent concentrations (5%). These results are significant because they suggest that condensates may be a source of endocrine-disrupting compounds in BKPM effluents and RO may reduce their discharge. [source] FIELD AND EXPERIMENTAL EVIDENCE FOR COMPETITION'S ROLE IN PHENOTYPIC DIVERGENCEEVOLUTION, Issue 2 2007David W. Pfennig Resource competition has long been viewed as a major cause of phenotypic divergence within and between species. Theory predicts that divergence arises because natural selection favors individuals that are phenotypically dissimilar from their competitors. Yet, there are few conclusive tests of this key prediction. Drawing on data from both natural populations and a controlled experiment, this paper presents such a test in tadpoles of two species of spadefoot toads (Spea bombifrons and S. multiplicata). These two species show exaggerated divergence in trophic morphology where they are found together (mixed-species ponds) but not where each is found alone (pure-species ponds), suggesting that they have undergone ecological character displacement. Moreover, in pure-species ponds, both species exhibit resource polymorphism. Using body size as a proxy for fitness, we found that in pure-species ponds disruptive selection favors extreme trophic phenotypes in both species, suggesting that intraspecific competition for food promotes resource polymorphism. In mixed-species ponds, by contrast, we found that trophic morphology was subject to stabilizing selection in S. multiplicata and directional selection in S. bombifrons. A controlled experiment revealed that the more similar an S. multiplicata was to its S. bombifrons tankmate in resource use, the worse was its performance. These results indicate that S. multiplicata individuals that differ from S. bombifrons would be selectively favored in competition. Our data therefore demonstrate how resource competition between phenotypically similar individuals can drive divergence between them. Moreover, our results indicate that how competition contributes to such divergence may be influenced not only by the degree to which competitors overlap in resource use, but also by the abundance and quality of resources. Finally, our finding that competitively mediated disruptive selection may promote resource polymorphism has potentially important implications for understanding how populations evolve in response to heterospecific competitors. In particular, once a population evolves resource polymorphism, it may be more prone to undergo ecological character displacement. [source] CHARACTER DISPLACEMENT AS THE "BEST OF A BAD SITUATION": FITNESS TRADE-OFFS RESULTING FROM SELECTION TO MINIMIZE RESOURCE AND MATE COMPETITIONEVOLUTION, Issue 10 2005Karin S. Pfennig Abstract Character displacement has long been considered a major cause of adaptive diversification. When species compete for resources or mates, character displacement minimizes competition by promoting divergence in phenotypes associated with resource use (ecological character displacement) or mate attraction (reproductive character displacement). In this study, we investigated whether character displacement can also have pleiotropic effects that lead to fitness trade-offs between the benefits of avoiding competition and costs accrued in other fitness components. We show that both reproductive and ecological character displacement have caused spadefoot toads to evolve smaller body size in the presence of a heterospecific competitor. Although this shift in size likely arose as a by-product of character displacement acting to promote divergence between species in mating behavior and larval development, it concomitantly reduces offspring survival, female fecundity, and sexual selection on males. Thus, character displacement may represent the "best of a bad situation" in that it lessens competition, but at a cost. Individuals in sympatry with the displaced phenotype will have higher fitness than those without the displaced trait because they experience reduced competition, but they may have reduced fitness relative to individuals in allopatry. Such a fitness trade-off can limit the conditions under which character displacement evolves and may even increase the risk of "Darwinian extinction" in sympatric populations. Consequently, character displacement may not always promote diversification in the manner that is often expected. [source] Nutrient dependent effects of consumer identity and diversity on freshwater ecosystem functionFRESHWATER BIOLOGY, Issue 1 2008ANDREW R. DZIALOWSKI Summary 1. Over the past decade, ecologists have tried to determine how changes in species composition and diversity affect ecosystem structure and function. Until recently, the majority of these studies have been conducted in terrestrial ecosystems and have not taken into account environmental variability. The purpose of this research was to determine how species identity and diversity in the freshwater zooplankton affected biomass of algae and zooplankton at two levels of nutrient enrichment. 2. Several species of cladocerans were grown alone and together in microcosms at both ambient and raised phosphorus concentrations to determine if the effects of consumer identity and diversity were nutrient dependent. 3. Total zooplankton biomass was greater, while algal biomass was lower, in mixed culture than in monoculture. The effects of zooplankton diversity on algal biomass, however, were only observed at raised phosphorus concentrations, suggesting that diversity effects were nutrient dependent. Specifically, diversity effects appeared to be related with biological mechanisms such as complementarity in resource use and/or facilitation. 4. More diverse communities of zooplankton appear to be better able to control algae than single species of zooplankton at high nutrient concentrations; therefore, zooplankton diversity may provide a buffer against eutrophication in freshwater ecosystems. [source] | |||||||||||||||||||||||||||||||||||||