1,170 research outputs found

    An evaluation of Bradfordizing effects

    Get PDF
    The purpose of this paper is to apply and evaluate the bibliometric method Bradfordizing for information retrieval (IR) experiments. Bradfordizing is used for generating core document sets for subject-specific questions and to reorder result sets from distributed searches. The method will be applied and tested in a controlled scenario of scientific literature databases from social and political sciences, economics, psychology and medical science (SOLIS, SoLit, USB Köln Opac, CSA Sociological Abstracts, World Affairs Online, Psyndex and Medline) and 164 standardized topics. An evaluation of the method and its effects is carried out in two laboratory-based information retrieval experiments (CLEF and KoMoHe) using a controlled document corpus and human relevance assessments. The results show that Bradfordizing is a very robust method for re-ranking the main document types (journal articles and monographs) in today’s digital libraries (DL). The IR tests show that relevance distributions after re-ranking improve at a significant level if articles in the core are compared with articles in the succeeding zones. The items in the core are significantly more often assessed as relevant, than items in zone 2 (z2) or zone 3 (z3). The improvements between the zones are statistically significant based on the Wilcoxon signed-rank test and the paired T-Test

    Investigative Tools and Techniques for Indoor Air Quality Studies

    Get PDF
    Indoor air quality problems are diverse and often complex. Adverse indoor air quality problems can exist which create symptomatic conditions for building occupants. Often, the exact cause, or causes, of the substandard indoor air quality are unknown. Therefore, an investigative approach must usually be taken to identify the source(s) of the air quality problem, and if present, air contaminant concentrations. As the general public becomes more aware of the problems associated with poor indoor air quality conditions, an associated increase in air quality evaluation requests can be expected. This paper discusses some of the various investigative tools and techniques that can be utilized to identify air quality contaminants when performing an indoor air quality evaluation. These investigative tools and techniques can be used to develop a site specific list of possible contaminants and their sources, and can then be used to determine which contaminants are, in fact, present in adverse concentrations. Some of the investigative tools and techniques to be discussed in this paper include the following: visual inspections and site observations, information searches, review of building construction, review of ventilation systems, interviews, low and high volume sampling pumps, flow and oxygen meters, portable photoionization and flame ionization detectors (PID & FID), various types of vapor detector tubes, and gas chromatograph/mass spectrophotometer (GC/MS) analysis. This paper will be an introductory overview of the above listed investigative tools and techniques. The paper's attempt is to acquaint the reader with these investigative tools and techniques, and how they can assist the reader in an air quality evaluation

    Investigative Tools and Techniques for Indoor Air Quality Studies

    Get PDF
    Indoor air quality problems are diverse and often complex. Adverse indoor air quality problems can exist which create symptomatic conditions for building occupants. Often, the exact cause, or causes, of the substandard indoor air quality are unknown. Therefore, an investigative approach must usually be taken to identify the source(s) of the air quality problem, and if present, air contaminant concentrations. As the general public becomes more aware of the problems associated with poor indoor air quality conditions, an associated increase in air quality evaluation requests can be expected. This paper discusses some of the various investigative tools and techniques that can be utilized to identify air quality contaminants when performing an indoor air quality evaluation. These investigative tools and techniques can be used to develop a site specific list of possible contaminants and their sources, and can then be used to determine which contaminants are, in fact, present in adverse concentrations. Some of the investigative tools and techniques to be discussed in this paper include the following: visual inspections and site observations, information searches, review of building construction, review of ventilation systems, interviews, low and high volume sampling pumps, flow and oxygen meters, portable photoionization and flame ionization detectors (PID & FID), various types of vapor detector tubes, and gas chromatograph/mass spectrophotometer (GC/MS) analysis. This paper will be an introductory overview of the above listed investigative tools and techniques. The paper's attempt is to acquaint the reader with these investigative tools and techniques, and how they can assist the reader in an air quality evaluation

    Where are commodity crops certified, and what does it mean for conservation and poverty alleviation?

    Get PDF
    Voluntary sustainability standards have expanded dramatically over the last decade. In the agricultural sector, such standards aim to ensure environmentally and socially sustainable production of a variety of commodity crops. However, little is known about where agricultural certification operates and whether certified lands are best located for conserving the world's most important biodiversity and benefiting the most vulnerable producers. To examine these questions we developed the first global map of commodity crop certification, synthesizing data from over one million farms to reveal the distribution of certification in unprecedented detail. It highlights both geographical clusters of certification as well as spatial bias in the location of certification with respect to environmental, livelihood and physical variables. Excluding organic certification, for which spatial data were not available, most certification of commodity crops is in tropical regions. Certification appears to be concentrated in areas important for biodiversity conservation, but not in those areas most in need of poverty alleviation, although there were exceptions to each of these patterns. We argue that the impact of sustainability standards could be increased by identifying places where it would be most beneficial to strengthen, consolidate, and expand certification. To achieve this, standards organizations will need to undertake more rigorous collection of spatial data, and more detailed analysis of their existing reach and impacts, with attention to potential trade-offs between different objectives. Efforts to promote spatial prioritization will require new partnerships to align specific conservation aims with the interests and capabilities of farmers

    Standing up in Multiple Sclerosis (SUMS): Protocol for a multi-centre randomised controlled trial evaluating the clinical and cost effectiveness of a home-based self-management standing frame programme in people with progressive multiple sclerosis.

    Get PDF
    This study is funded by the NIHR Health Technology Assessment Programme (14/176/12), United Kingdom.Background:  Impaired mobility is a cardinal feature of multiple sclerosis (MS) and is rated by people with MS as their highest priority. By the secondary progressive phase, balance, mobility and physical activity levels are significantly compromised; an estimated 70% of people with secondary progressive MS fall regularly. Our ongoing research has systematically developed ‘Balance Right in MS’ (BRiMS), an innovative, manualised 13-week guided self-management programme tailored to the needs of people with MS, designed to improve safe mobility and minimise falls. Our eventual aim is to assess the clinical and cost effectiveness of BRiMS in people with secondary progressive MS by undertaking an appropriately statistically powered, multi-centre, assessor-blinded definitive, randomised controlled trial. This feasibility study will assess the acceptability of the intervention and test the achievability of running such a definitive trial. Methods/design:  This is a pragmatic multi-centre feasibility randomised controlled trial with blinded outcome assessment. Sixty ambulant people with secondary progressive MS who self-report two or more falls in the previous 6 months will be randomly allocated (1:1) to either the BRiMS programme plus usual care or to usual care alone. All participants will be assessed at baseline and followed up at 15 weeks and 27 weeks post-randomisation. The outcomes of this feasibility trial include: • Feasibility outcomes, including trial recruitment, retention and completion • Assessment of the proposed outcome measures for the anticipated definitive trial (including measures of walking, quality of life, falls, balance and activity level) • Measures of adherence to the BRiMS programme • Data to inform the economic evaluation in a future trial • Process evaluation (assessment of treatment fidelity and qualitative evaluation of participant and treating therapist experience) Discussion:  The BRiMS intervention aims to address a key concern for MS service users and providers. However, there are several uncertainties which need to be addressed prior to progressing to a full-scale trial, including acceptability of the BRiMS intervention and practicality of the trial procedures. This feasibility trial will provide important insights to resolve these uncertainties and will enable a protocol to be finalised for use in the definitive trial.Publisher PDFPeer reviewe

    Incubation of ovine scrapie with environmental matrix results in biological and biochemical changes of PrPSc over time

    Get PDF
    Ovine scrapie can be transmitted via environmental reservoirs. A pool of ovine scrapie isolates were incubated on soil for one day or thirteen months and eluted prion was used to challenge tg338 mice transgenic for ovine PrP. After one-day incubation on soil, two PrPSc phenotypes were present: G338 or Apl338ii. Thirteen months later some divergent PrPSc phenotypes were seen: a mixture of Apl338ii with either G338 or P338, and a completely novel PrPSc deposition, designated Cag338. The data show that prolonged ageing of scrapie prions within an environmental matrix may result in changes in the dominant PrPSc biological/biochemical properties

    Does the presence of scrapie affect the ability of current statutory discriminatory tests to detect the presence of BSE?

    Get PDF
    Current European Commission (EC) surveillance regulations require discriminatory testing of all transmissible spongiform encephalopathy (TSE)-positive small ruminant (SR) samples in order to classify them as bovine spongiform encephalopathy (BSE) or non-BSE. This requires a range of tests, including characterization by bioassay in mouse models. Since 2005, naturally occurring BSE has been identified in two goats. It has also been demonstrated that more than one distinct TSE strain can coinfect a single animal in natural field situations. This study assesses the ability of the statutory methods as listed in the regulation to identify BSE in a blinded series of brain samples, in which ovine BSE and distinct isolates of scrapie are mixed at various ratios ranging from 99% to 1%. Additionally, these current statutory tests were compared with a new in vitro discriminatory method, which uses serial protein misfolding cyclic amplification (sPMCA). Western blotting consistently detected 50% BSE within a mixture, but at higher dilutions it had variable success. The enzyme-linked immunosorbent assay (ELISA) method consistently detected BSE only when it was present as 99% of the mixture, with variable success at higher dilutions. Bioassay and sPMCA reported BSE in all samples where it was present, down to 1%. sPMCA also consistently detected the presence of BSE in mixtures at 0.1%. While bioassay is the only validated method that allows comprehensive phenotypic characterization of an unknown TSE isolate, the sPMCA assay appears to offer a fast and cost-effective alternative for the screening of unknown isolates when the purpose of the investigation was solely to determine the presence or absence of BSE

    Open Government Data: A Focus on Key Economic and Organizational Drivers

    Get PDF
    Grounding the analysis on multidisciplinary literature on the topic, the existing EU legislation and relevant examples, this working paper aims at highlighting some key economic and organizational aspects of the "Open Government Data" paradigm and its drivers and implications within and outside Public Administrations. The discussion intends to adopt an "Internet Science" perspective, taking into account as enabling factors the digital environment itself, as well as specific models and tools. More "traditional" and mature markets grounded on Public Sector Information are also considered, in order to indirectly detect the main differences with respect to the aforementioned paradig
    • …
    corecore