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Since AMBI was published originally in 2000, it has been used in an increasing number of investigations with monitoring purposes, or to analyse impacts on soft-bottom macrobenthic communities. Some guidelines for its correct use were published in 2005; however, a main issue remained without an answer — which are the minimal area and number of replicates necessary, to obtain a precise estimate for AMBI? In this study, new methodologies such as bootstrap techniques have been applied to this particular problem.Data were obtained from sampling carried out in 1995, within the framework of the Littoral Water Quality Monitoring and Control Network of the Basque Country (northern Spain). The sampling strategy consisted of 11 intertidal estuarine sampling stations (0.25m2, sampled for each of six replicates) and 17 subtidal estuarine and coastal sampling stations (0.125m2, sampled for each of six replicates).Two replicates have been established as being sufficient, both for intertidal and subtidal sampling stations, to classify 80% of the pseudosamples into the same disturbance level, in terms of AMBI, for 64% of the stations.For the minimal area, it has been determined also (for both intertidal and subtidal sampling stations) that 0.25m2 is sufficient to classify 80% of the iterations into the same disturbance level, for 64% of the stations.  相似文献   

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Abstract This paper describes a simple and inexpensive procedure for the rapid biological assessment of water quality in rivers and streams in eastern Australia. The procedure involves the standardized collection of samples of 100 macroinvertebrates from defined habitat types within a water body. Specimens are identified to family level only and a biotic index is calculated. Proposed future testing and evaluation are described, and the limitations of the rapid approach are discussed.  相似文献   

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On Lombok island, in the province of West Nusa Tenggara, Indonesia, indigenous medicine and biomedicine coexist. Nevertheless, biomedicine, a product of modernity and the development of the state has been superimposed on village life along with other state institutions such as education. In this paper I analyse the processes involved in Sasak villagers' quest for health. Operating within various and sometimes overlapping social fields and conflicting discourses, villagers utilise both local indigenous practices as well as the Indonesian national health system in their quest. Because local or ordinary knowledge is a rich resource for interpretation, I describe the health quest through the participant individuals: family members, neighbours, doctors and nursing personnel involved. The subjectivity of the individual participants contributes to the intricate unfolding of health seeking quests to expose the various tensions which emerge between tradition (tradisi [I]) and modernity (moderen [I]) and between state and village.  相似文献   

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Lameness in dairy cows is an important welfare issue. As part of a welfare assessment, herd level lameness prevalence can be estimated from scoring a sample of animals, where higher levels of accuracy are associated with larger sample sizes. As the financial cost is related to the number of cows sampled, smaller samples are preferred. Sequential sampling schemes have been used for informing decision making in clinical trials. Sequential sampling involves taking samples in stages, where sampling can stop early depending on the estimated lameness prevalence. When welfare assessment is used for a pass/fail decision, a similar approach could be applied to reduce the overall sample size. The sampling schemes proposed here apply the principles of sequential sampling within a diagnostic testing framework. This study develops three sequential sampling schemes of increasing complexity to classify 80 fully assessed UK dairy farms, each with known lameness prevalence. Using the Welfare Quality herd-size-based sampling scheme, the first ‘basic’ scheme involves two sampling events. At the first sampling event half the Welfare Quality sample size is drawn, and then depending on the outcome, sampling either stops or is continued and the same number of animals is sampled again. In the second ‘cautious’ scheme, an adaptation is made to ensure that correctly classifying a farm as ‘bad’ is done with greater certainty. The third scheme is the only scheme to go beyond lameness as a binary measure and investigates the potential for increasing accuracy by incorporating the number of severely lame cows into the decision. The three schemes are evaluated with respect to accuracy and average sample size by running 100 000 simulations for each scheme, and a comparison is made with the fixed size Welfare Quality herd-size-based sampling scheme. All three schemes performed almost as well as the fixed size scheme but with much smaller average sample sizes. For the third scheme, an overall association between lameness prevalence and the proportion of lame cows that were severely lame on a farm was found. However, as this association was found to not be consistent across all farms, the sampling scheme did not prove to be as useful as expected. The preferred scheme was therefore the ‘cautious’ scheme for which a sampling protocol has also been developed.  相似文献   

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BACKGROUND: The assessment of the data quality of population-based registration systems is essential to understanding the reliability and usefulness of disease surveillance and research findings resulting from the use of registry data. Since the New York State Congenital Malformations Registry (CMR) uses passive case ascertainment, the completeness of the registry data is an important aspect of the quality of information. This paper presents the results of hospital audits, which were conducted to capture the unreported cases using hospital discharge files, and evaluates the effectiveness of the audits. METHODS: Children age 2 years or younger and diagnosed with reportable birth defects for the birth years 1998-2000 were selected from hospital discharge files of all reporting hospitals in the New York Statewide Planning and Research Cooperative System (SPARCS) and matched to the CMR database for the same birth year period.The unmatched reports from the SPARCS hospital discharge files that the CMR possibly missed were sent to hospitals, requesting submission of the missed reports. Two audits on all reporting hospitals in New York State were conducted: 1) 1998 and 1999 birth cohorts audited from June 2000 to March 2002, and 2) 2000 birth cohort audited from November 2001 to November 2002. RESULTS: Hospital audits using SPARCS hospital discharge data identified 5,460 reports that the CMR missed for the selected 66 hospitals analyzed. About 86% of these reports had reportable conditions and were added to the CMR, which comprised 21.4% of all reports from the 66 hospitals for the birth years 1998-2000. The number of reports that would have been missed without audits decreased from the 1998 and 1999 birth cohort (25.1%) to the 2000 birth cohort (13.9%). Low reporting rates and, thus, a high percent of added reports, were found for hospitals with a relatively small number of annual reports and for some specific birth defects such as chromosomal anomalies, anencephalus and congenital anomalies of the urinary system. CONCLUSION: The current study demonstrates that using hospital discharge data to improve case ascertainment is a valuable and effective method of enhancing birth defect surveillance, particularly for those hospitals with low reporting rates.  相似文献   

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BackgroundPractice facilitation (PF), a multifaceted approach in which facilitators (external health care professionals) help family physicians to improve their adoption of best practices, has been highly successful. Improved Delivery of Cardiovascular Care (IDOCC) was an innovative PF trial designed to improve evidence-based care for people who have, or are at risk of, cardiovascular disease (CVD). The intervention was found to be ineffective as assessed by a patient-level composite score based on chart reviews from a subsample of patients (N = 5292). Here, we used population-based administrative data to examine IDOCC’s effect on CVD-related hospitalizations.MethodsIDOCC used a pragmatic, stepped wedge cluster randomized controlled design involving primary care providers recruited across Eastern Ontario, Canada. IDOCC’s effect on CVD-related hospitalizations was assessed in the 2 years of active intervention and post-intervention years. Marginal and mixed-effects regression analyses were used to account for the study design and to control for patient, physician, and practice characteristics. Secondary and subgroup analyses investigated robustness.ResultsOur sample included 262,996 patient/year observations representing 54,085 unique patients who had, or were at risk of, CVD, from 70 practices. There was a strong decreasing secular trend in CVD-related hospitalizations but no statistically significant effect of IDOCC. Relative to patients in the control condition, patients in the intervention condition were estimated to have 4 % lower odds of CVD-related hospitalizations (adjOR = 0.96, 99 % CI 0.83 to 1.11). The nonsignificant result persisted across robustness analyses.ConclusionsClinical outcomes from administrative databases were examined to form a more complete picture of the (in)effectiveness of a large-scale quality improvement intervention. IDOCC did not have a significant effect on CVD hospitalizations, suggesting that the results from the primary composite adherence score analysis were neither due to choice of outcome nor relatively short follow-up period.

Trial registration

ClinicalTrials.gov NCT00574808, registered on 14 December 2007.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1547-2) contains supplementary material, which is available to authorized users.  相似文献   

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We have implemented a technique combining allele-specific PCR (AS-PCR) and denaturing high-performance liquid chromatography (DHPLC) to identify new polymorphic variants within an intergenic region in the beta-globin cluster. This technique is applicable to the detection of new variants in genomic regions where variation is apportioned into distinct classes of haplotype. Duplexes for DHPLC analysis were created by denaturation and re-annealing of a mixture of two AS-PCR products of known and unknown sequence from the same haplotypic class, permitting detection of new haplotypes in each class. A 454bp fragment 3.5kb 5' to the human delta-globin gene, which may have a gene regulatory function, was analysed in 840 chromosomes from a global sampling of human populations using this method. Two divergent haplotypes were found to predominate in all populations studied, possibly as a result of balancing selection.  相似文献   

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In this article I discuss the role of money vis-à-vis health care among the Dagomba, an agrarian people living in northern Ghana, whose pluralistic medical culture involves the use of both plants and Western pharmaceuticals in the treatment of various symptoms. In Dagomba society monetary exchanges in the domain of healing cannot be equated with self-interest, and nonmonetary exchanges cannot be compared with altruism in any straightforward fashion. Exchanges and their purposes are made meaningful by the contexts in which they occur. Exchanges may involve money and be commoditized. However, the very fact that such an exchange is made in a "benevolent and considerate manner" (which often means selling/buying on credit) transforms otherwise impersonal relationships between medicine sellers and their customers into displays of solidarity with the communal (collective) goals of Dagomba society.  相似文献   

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Purpose

The demand for household batteries is considerable in the European context with just over five billion placed on the market every year. Although disposable batteries account for the largest market share in Europe, the use of rechargeable batteries is promoted as a less waste generating and a more environmentally friendly practice. A comparative life cycle assessment was therefore carried out to verify this assertion.

Methods

The study compared, with a life cycle perspective, the use of disposable alkaline batteries to that of rechargeable NiMH batteries, considering the AA and AAA sizes. The comparison focused on the factors that were expected to have an higher influence on the results: consumer choices during the purchase for disposable devices (typology of battery pack, selected brand, which affects the production country, and mode of transport of batteries for the purchasing round trip) and during the use phase for rechargeable batteries (number of charge cycles and source of the electricity used for the recharge). The waste generation indicator, 13 midpoint impact indicators on the environment and the human health, and the Cumulative energy demand indicator were calculated in support of the assessment.

Results and discussion

For waste generation, the choice of NiMH rechargeable batteries is highly convenient also with a reduced number of uses. On the contrary, for the environmental indicators and the energy consumption, the picture is less straightforward, being heavily dependent on the number of charge cycles. For the impact categories Acidification, Human toxicity (cancer effects), and Particulate matter, an “inefficient” use of the rechargeable devices (for only 20 charge cycles or less) could cause higher impacts than the employment of disposable batteries. Moreover, for the Ozone depletion, NiMH batteries are hardly environmentally better than alkaline batteries even with 150 recharges.

Conclusions and recommendations

The number of uses of rechargeable batteries plays a key role on their environmental and energy performances. When compared to disposable batteries, a minimum number of 50 charge cycles permits a robust reduction of the potential impacts for all the analyzed indicators excluding the Ozone depletion. Hence, the use of rechargeable batteries should be mostly encouraged for high consumption devices such as cameras, torches, and electronic toys.
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