227 research outputs found
Impact Evaluation of Wet-Weather Events on Influent Flow and Loadings of a Water Resource Recovery Facility
Since the introduction of environmental legislation anddirectives in Europe, the impact of combined sewer overflows (CSO) on receiving waterbodies has become a priority concern in water and wastewater treatment industry. Timeconsumingand expensive local sampling and monitoring campaigns have been carried outto estimate the characteristic flow and pollutant concentrations of CSO water. This studyfocused on estimating the frequency and duration of wet-weather events and their impactson influent flow and wastewater characteristics of the largest Italian water resource recoveryfacility (WRRF) in Castiglione Torinese. Eight years (viz. 2009-2016) of routinely collectedinfluent data in addition to the arithmetic mean daily precipitation rates (PI) of the plantcatchment area, were elaborated. Relationships between PI and volumetric influent flow rate(Qin), chemical oxygen demand (COD), ammonium concentration (N-NH4) and totalsuspended solids (TSS) are investigated. Time series data mining (TSDM) method isimplemented for segmentation of time series by use of sliding window algorithm to partitionthe available records associated with wet and dry weather events based on the dailyvariation of PI time series. Appling the methodology in conjunction with results obtained fromdata reduction techniques, a wet-weather definition is proposed for the plant. The resultsconfirm that applied methodology on routinely collected plant data can be considered as agood substitute for time-consuming and expensive sampling campaigns and plantmonitoring programs usually conducted for accurate emergency response and long-termpreparedness for extreme climate conditions
Improving the eco-efficiency of an agricultural water use system
During the last two decades, the concept of eco-efficiency has been recognized as a suitable measure of progress towards a greener and more sustainable economy. The prefix “eco-” refers to both economic and ecological (environmental) performance. The need for improving eco-efficiency leads to the challenge of identifying the most promising alternative solutions which improve both the economic and the environmental performance of a given system (“eco-innovations”). Therefore, it becomes critical to develop eco-efficiency metrics for measuring environmental and economic performance of a system.
The current paper presents a methodological framework that attempts to explore the use of eco-efficiency indicators in meso-level water use systems and through them to assess the impact of innovative technologies in such systems. The assessment of the environmental performance follows a life-cycle oriented approach using the midpoint impact categories while the economic performance is measured using the Total Value Added to the product due to water use. The eco-efficiency is expressed as the ratio of the economic performance indicator to the environmental performance indicator. The proposed approach is applied to a water use system of the agricultural sector, and more specifically to the fresh form tomato crop production in Phthiotida.
The analysis reveals that the most important environmental impacts of the system are (i) greenhouse gas emissions due to energy consumption, (ii) release of toxic substances, due to the use of fertilizers and pesticides and (iii) depletion of freshwater resources. Three alternative interventions are examined for upgrading the value chain: (i) installation of sub-surface drip irrigation system, (ii) replacement of diesel pumps with solar pumps and (iii) use of organic fertilizers.
Based on the findings, all of the proposed interventions have a positive impact on the overall eco-efficiency of the system. Sub-surface drip irrigation is the least favorable mainly due to its high investment cost. The use of solar pumps strongly influences climate change and photochemical ozone formation while the use of organic fertilizers has a more balanced impact on all indicators, with an emphasis on eutrophication. Thus, for a more holistic approach, regarding the eco-efficiency performance, a combined application of these three scenarios may be proposed
Endocrine correlates of male breast cancer risk: a case-control study in Athens, Greece
We studied the relation of certain endocrine-related variables among 23 cases of male breast cancer and 76 apparently healthy male controls. There were significant inverse associations with smoking (P = 0.03), birth order (P = 0.02) and reported frequency of orgasms in later life (P = 0.0004). The study provides strong indirect evidence that endocrine factors are important in the aetiology of male breast cancer. © 2000 Cancer Research Campaig
Data envelopment analysis in financial services: a citations network analysis of banks, insurance companies and money market funds
Development and application of the data envelopment analysis (DEA) method, have been the subject of numerous reviews. In this paper, we consider the papers that apply DEA methods specifically to financial services, or which use financial services data to experiment with a newly introduced DEA model. We examine 620 papers published in journals indexed in the Web of Science database, from 1985 to April 2016. We analyse the sample applying citations network analysis. This paper investigates the DEA method and its applications in financial services. We analyse the diffusion of DEA in three sub-samples: (1) banking groups, (2) money market funds, and (3) insurance groups by identifying the main paths, that is, the main flows of the ideas underlying each area of research. This allows us to highlight the main approaches, models and efficiency types used in each research areas. No unique methodological preference emerges within these areas. Innovations in the DEA methodologies (network models, slacks based models, directional distance models and Nash bargaining game) clearly dominate recent research. For each subsample, we describe the geographical distribution of these studies, and provide some basic statistics related to the most active journals and scholars
Efficiency and productivity changes in Greek airports during the crisis years 2010–2014
© 2016 Elsevier Ltd The aim of this study is to evaluate the operating efficiency and productivity changes of the Greek airports, during the first years of the severe economic crisis in Greece (2010–2014), by using two methods: Data Envelopment Analysis (DEA) and Malmquist Productivity index (MPI). Findings have shown that, despite the dramatic effects of the economic crisis on the socio-economic life of the country, overall airport efficiency and productivity improved, mainly due to exogenous factors such as international tourism growth. The MPI reveals that over the period of the study, airports have experienced an annual average increase in total factor productivity (TFP) of 0.9% (an increase of 3.6% over the examined period). On examining the components of this productivity change, it becomes evident that this is due to the combination of both positive (a slight progress) annual average technology change (0.5%) and technical efficiency change (0.4%). The results also indicate that 65.8% of airports have an increase in average TFP during the period 2010–2014, ranging between 0.4% and 20%. However, as Greek airports operate at poor levels of efficiency, there is still considerable space for improvements in most of the airports
Field Studies Reveal Strong Postmating Isolation between Ecologically Divergent Butterfly Populations
A mismatch between hybrid butterflies and their ecological environment restricts gene flow between populations that feed on different host plants, highlighting the potential importance of a seldom-studied mechanism of reproductive isolation
Next-generation HLA typing of 382 International Histocompatibility Working Group reference B-lymphoblastoid cell lines: Report from the 17th International HLA and Immunogenetics Workshop
Extended molecular characterization of HLA genes in the IHWG reference B-lymphoblastoid cell lines (B-LCLs) was one of the major goals for the 17th International HLA and Immunogenetics Workshop (IHIW). Although reference B-LCLs have been examined extensively in previous workshops complete high-resolution typing was not completed for all the classical class I and class II HLA genes. To address this, we conducted a single-blind study where select panels of B-LCL genomic DNA samples were distributed to multiple laboratories for HLA genotyping by next-generation sequencing methods. Identical cell panels comprised of 24 and 346 samples were distributed and typed by at least four laboratories in order to derive accurate consensus HLA genotypes. Overall concordance rates calculated at both 2- and 4-field allele-level resolutions ranged from 90.4% to 100%. Concordance for the class I genes ranged from 91.7 to 100%, whereas concordance for class II genes was variable; the lowest observed at HLA-DRB3 (84.2%). At the maximum allele-resolution 78 B-LCLs were defined as homozygous for all 11 loci. We identified 11 novel exon polymorphisms in the entire cell panel. A comparison of the B-LCLs NGS HLA genotypes with the HLA genotypes catalogued in the IPD-IMGT/HLA Database Cell Repository, revealed an overall allele match at 68.4%. Typing discrepancies between the two datasets were mostly due to the lower-resolution historical typing methods resulting in incomplete HLA genotypes for some samples listed in the IPD-IMGT/HLA Database Cell Repository. Our approach of multiple-laboratory NGS HLA typing of the B-LCLs has provided accurate genotyping data. The data generated by the tremendous collaborative efforts of the 17th IHIW participants is useful for updating the current cell and sequence databases and will be a valuable resource for future studies
The evolution of reproductive isolation in a simultaneous hermaphrodite, the freshwater snail Physa
<p>Abstract</p> <p>Background</p> <p>The cosmopolitan freshwater snail <it>Physa acuta </it>has recently found widespread use as a model organism for the study of mating systems and reproductive allocation. Mitochondrial DNA phylogenies suggest that <it>Physa carolinae</it>, recently described from the American southeast, is a sister species of <it>P. acuta</it>. The divergence of the <it>acuta/carolinae </it>ancestor from the more widespread <it>P. pomilia </it>appears to be somewhat older, and the split between a hypothetical <it>acuta/carolinae/pomilia </it>ancestor and <it>P. gyrina </it>appears older still.</p> <p>Results</p> <p>Here we report the results of no-choice mating experiments yielding no evidence of hybridization between <it>gyrina </it>and any of four other populations (<it>pomilia, carolinae</it>, Philadelphia <it>acuta</it>, or Charleston <it>acuta</it>), nor between <it>pomilia </it>and <it>carolinae</it>. Crosses between <it>pomilia </it>and both <it>acuta </it>populations yielded sterile F1 progeny with reduced viability, while crosses between <it>carolinae </it>and both <it>acuta </it>populations yielded sterile F1 hybrids of normal viability. A set of mate-choice tests also revealed significant sexual isolation between <it>gyrina </it>and all four of our other <it>Physa </it>populations, between <it>pomilia </it>and <it>carolinae</it>, and between <it>pomilia </it>and Charleston <it>acuta</it>, but not between <it>pomilia </it>and the <it>acuta </it>population from Philadelphia, nor between <it>carolinae </it>and either <it>acuta </it>population. These observations are consistent with the origin of hybrid sterility prior to hybrid inviability, and a hypothesis that speciation between <it>pomilia </it>and <it>acuta </it>may have been reinforced by selection for prezygotic reproductive isolation in sympatry.</p> <p>Conclusions</p> <p>We propose a two-factor model for the evolution of postzygotic reproductive incompatibility in this set of five <it>Physa </it>populations consistent with the Dobzhansky-Muller model of speciation, and a second two-factor model for the evolution of sexual incompatibility. Under these models, species trees may be said to correspond with gene trees in American populations of the freshwater snail, <it>Physa</it>.</p
Effects of radiotherapy and surgery in early breast cancer: an overview of the randomized trials
Background
Randomized trials of radiotherapy and surgery for early breast cancer may have been too small to detect differences in long-term survival and recurrence reliably. We therefore performed a systematic overview (meta-analysis) of the results of such trials.
Methods
Information was sought on each subject from investigators who conducted trials that began before 1985 and that compared local therapies for early breast cancer. Data on mortality were available from 36 trials comparing radiotherapy plus surgery with the same type of surgery alone, 10 comparing more-extensive surgery with less-extensive surgery, and 18 comparing more-extensive surgery with less-extensive surgery plus radiotherapy. Information on mortality was available for 28,405 women (97.4 percent of the 29,175 women in the trials).
Results
The addition of radiotherapy to surgery resulted in a rate of local recurrence that was three times lower than the rate with surgery alone, but there was no significant difference in 10-year survival; among a total of 17,273 women enrolled in such trials, mortality was 40.3 percent with radiotherapy and 41.4 percent without radiotherapy (P = 0.3). Radiotherapy was associated with a reduced risk of death due to breast cancer (odds ratio, 0.94; 95 percent confidence interval, 0.88 to 1.00; P = 0.03), which indicates that, after 10 years, there would be about 0 to 5 fewer deaths due to breast cancer per 100 women. However, there was an increased risk of death from other causes (odds ratio, 1.24; 95 percent confidence interval, 1.09 to 1.42; P = 0.002). This, together with the age-specific death rates, implies, after 10 years, a few extra deaths not due to breast cancer per 100 older women or per 1000 younger women. During the first decade or two after diagnosis, the excess in the rate of such deaths that was associated with radiotherapy was much greater among women who were over 60 years of age at randomization (15.3 percent vs. 11.1 percent [339 vs. 249 deaths]) than among those under 50 (2.5 percent vs. 2.0 percent [62 vs. 49 deaths]). Breast-conserving surgery involved some risk of recurrence in the remaining tissue, but no significant differences in overall survival at 10 years were found in the studies of mastectomy versus breast-conserving surgery plus radiotherapy (4891 women), more-extensive surgery versus less-extensive surgery (4818 women), or axillary clearance versus radiotherapy as adjuncts to mastectomy (4370 women).
Conclusions
Some of the local therapies for breast cancer had substantially different effects on the rates of local recurrence — such as the reduced recurrence with the addition of radiotherapy to surgery — but there were no definite differences in overall survival at 10 years
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