bluuebunny/crossref_metadata_2025_split huggingface dataset:
How Effective Is Thermal Remediation of DNAPL Source Zones in Reducing Groundwater Concentrations?
Authors: Baker Ralph S. , Nielsen Steffen G. , Heron Gorm , Ploug Niels 
Published: March 2018

AbstractDense nonaqueous phase liquid (DNAPL) source areas containing chlorinated volatile organic compounds (cVOCs) such as trichloroethene (TCE) and perchloroethene (PCE) often give rise to significant dissolved plumes in groundwater, leading to the closure of downgradient water supply wells and creating vapor intrusion issues in buildings located above the plume. Hydraulic containment via pump‐and‐treat has often been implemented to limit migration but must continue indefinitely. Removal of the DNAPL source area by means such as in situ thermal remediation (ISTR) offers the potential to diminish or end the need for hydraulic containment if the associated dissolved plume attenuates sufficiently following source removal. A question often raised is whether this occurs or whether the back diffusion of contaminants from secondary sources such as low‐permeability lenses in the dissolved plume precludes it. The authors conducted DNAPL source removal using ISTR at dozens of sites. This paper presents a compilation of cases—10 separate DNAPL source areas at five project sites—where data indicate that the implementation of a thorough ISTR in a DNAPL source area can result in the attenuation of the associated dissolved plume, such that in several cases, long‐standing pump‐and‐treat systems could be turned off. Our findings contrast with recent assertions that aggressive source remediation may not be justifiable because dissolved plume concentrations will not decline sufficiently. We show that the application of ISTR can result in the thorough removal of the DNAPL source, effective diminution of dissolved plume groundwater concentrations, and achievement of drinking water standards.
Accumulation of Pesticides in Anaerobic Clayey Till‐Controls and Implications for Groundwater
Authors: Jørgensen Peter R. , Spliid Niels H. 
Published: March 2018

AbstractPesticide residuals after point‐source pesticide spills in clay‐rich aquitards may potentially affect underlying groundwater for many decades due to slow release of accumulated pollution in the clayey matrix material of the aquitard. In this study, we evaluated factors behind different degrees of accumulation of phenoxy acids (MCPP, dichlorprop, 2,4‐D MCPA) and triazines (simazine and terbutylazine) observed in an old pesticide pollution described by Jørgensen et al. (2016a, this issue). By using leaching experiments, it was shown that a zone of maximum concentrations of MCPP and dichlorprop (mg/L) observed by Jørgensen et al. (2016a, this issue) represented accumulated potentially mobile pollution in anaerobic, however largely immobile pore water of the clayey matrix in the upper few meters of the unoxidized aquitard zone. By using sorption experiments, we determined 9 to16 times higher mobility by diffusion and flow for the phenoxy acids (R = 1 to 2) than for the triazines (R = 9 to 16) in the clayey matrix material of the aquitard. This indicated that more rapid and greater accumulation could occur for the phenoxy acids in the clayey matrix than for the triazines. In contrast, the relative mobility of the phenoxy acids and triazines was much closer in sand‐filled fractures and thin sand layers/lamina in the clay, suggesting that the migration of the same compounds along these textural preferential flow paths into the underlying aquifer was less different. Despite that a greater mass had originally been spilled of 2,4‐D and MCPA having similar mobility as the accumulated MCPP and dichlorprop, these compounds were not accumulated in the zone of maximum concentrations. It is suggested that the controls, which initially allowed for the observed separate accumulation of MCPP and dichlorprop as a zone of maximum pollution, were due to the combination of high persistence and high mobility for these specific pesticides in the clayey till matrix material of the aquitard. The investigation showed that over time the initial high concentrations of the accumulated phenoxy acids (MCPP, dichlorprop) transformed into high concentrations of related mobile degradation products (e.g., 4‐CPP and 2‐CPP), which extended the total time of groundwater pollution beyond the disappearance of the original phenoxyacids.
An Excel®‐Based Visualization Tool of Two‐Dimensional Soil Gas Concentration Profiles in Petroleum Vapor Intrusion
Authors: Verginelli Iason , Yao Yijun , Suuberg Eric M. 
Published: March 2018

AbstractIn this study, we present a petroleum vapor intrusion (PVI) tool implemented in Microsoft® Excel® using Visual Basic for Applications and integrated within a graphical interface. The latter helps users easily visualize two‐dimensional soil gas concentration profiles and indoor concentrations as a function of site‐specific conditions such as source strength and depth, biodegradation reaction rate constant, soil characteristics and building features. This tool is based on a two‐dimensional explicit analytical model that combines steady‐state diffusion‐dominated vapor transport in a homogeneous soil with a piecewise first‐order aerobic biodegradation model, in which rate is limited by oxygen availability. As recommended in the recently released United States Environmental Protection Agency's final PVI guidance, a sensitivity analysis and a simplified Monte Carlo uncertainty analysis are also included in the spreadsheet.
Using Na/K Ratios to Identify the Potential Impacts of Sewage Effluent on Groundwater Quality in Sohag, Egypt
Authors: Redwan Mostafa , Abdel Moneim Ahmed A. 
Published: March 2018

AbstractImproper disposal of wastewater is an important source of groundwater contamination, as it poses serious threats to the environment and human health. In this case study, 18 groundwater and 3 sewage effluent samples were collected from the area adjacent to a wastewater treatment plant in Sohag, Egypt. These samples were subjected to detailed chemical and bacteriological analyses to quantify the potential impact of sewage effluent on the groundwater quality using geochemical indicators. The groundwater aquifer in the study area is represented by the highly permeable Qena Sands that are composed of sands and gravels. The bacteriological analyses indicated the presence of fecal coliform in groundwater at wells nearby the wastewater ponds and farm lands. NH4
concentration of the contaminated groundwater samples ranged from 0.36 to 5.70 mg/L (78% of the samples > 1.20 mg/L) and the NH4
in the non‐impacted samples ranged from 0.40 to 2.23 mg/L (22% > 1.20 mg/L). Variations in NH4
concentrations are due to the transformation processes occurring in the aquifer. The groundwater samples were categorized based on the Na/K ratio into two classes. The first class shows the Na/K ratios vary from 2.52 to 12.19 for sewage effluent and contaminated samples, while in the second class they range from 12.85 to 31.60 for non‐impacted samples. As a result, the Na/K ratio in combination with other chemical and microbiological indicators is a useful screening tool for assessing possible sewage influence on shallow groundwater from shallow wells.
Applying theHPT‐GWSfor Hydrostratigraphy, Water Quality and Aquifer Recharge Investigations
Authors: McCall Wesley , Christy Thomas M. , Evald Mateus K. 
Published: March 2018

AbstractThe primary objective of this study was to evaluate use of the hydraulic profiling tool‐groundwater sampler (HPT‐GWS) log data as an indicator of water quality (level of dissolved ionic species) in an alluvial aquifer. TheHPT‐GWSprobe is designed for direct push advancement into unconsolidated formations. The system provides both injection pressure logs and electrical conductivity (EC) logs, and groundwater may be sampled at multiple depths as the probe is advanced (profiling). The combination of these three capabilities in one probe has not previously been available. During field work it was observed that whenHPTcorrected pressure (Pc) indicates a consistent aquifer unit then bulk formationECcan be used as an indicator of water quality. A high correlation coefficient (R2= 0.93) was observed between groundwater specific conductance and bulk formationECin the sands and gravels of the alluvial aquifer studied. These results indicate that groundwater specific conductance is exerting a controlling influence on the bulk formationECof the coarse‐grained unit at this site, and probably many similar sites, consistent with Archie's Law. This simple relationship enables the use of theECand Pclogs, with targeted water samples and a minimum of core samples, to rapidly assess groundwater quality over extended areas at high vertical resolution. This method was used to identify both a brine impacted zone at the base of the aquifer investigated and a groundwater recharge lens developing below storm water holding ponds in the upper portion of the same aquifer. Sample results for trace level, naturally occurring elements (As, Ba, U) further demonstrate the use of this system to sample for low level groundwater contamination.
Data Analysis and Modeling to Optimize Thermal Treatment Cost and Performance
Authors: Parker Jack C. , Kim Ungtae , Fortune Alyson , Griepke Steffen , Galligan James P. , Bonarrigo Amber 
Published: March 2018

AbstractThe objective of in situ thermal treatment is typically to reduce the contaminant mass or average soil concentration below a specified value. Evaluation of whether the objective has been met is usually made by averaging soil concentrations from a limited number of soil samples. Results from several field sites indicate large performance uncertainty using this approach, even when the number of samples is large. We propose a method to estimate average soil concentration by fitting a log normal probability model to thermal mass recovery data. A statistical approach is presented for making termination decisions from mass recovery data, soil sample data, or both for an entire treatment volume or for subregions that explicitly considers estimation uncertainty which is coupled to a stochastic optimization algorithm to identify monitoring strategies to meet objectives with minimum expected cost. Early termination of heating in regions that reach cleanup targets sooner enables operating costs to be reduced while ensuring a high likelihood of meeting remediation objectives. Results for an example problem demonstrate that significant performance improvement and cost reductions can be achieved using this approach.
Remediation Decision‐Making and Behavioral Economics: Results of an Industry Survey
Authors: Clayton Wilson S. 
Published: March 2018

AbstractDecision methods applied in the remediation industry were evaluated using a survey of industry practitioners, in order to assess the relative roles of quantitative decision analysis and gut intuition. Principals from the disciplines of behavioral economics and decision theory were used as a framework to evaluate remediation decision behaviors revealed by the survey. The survey was completed by 118 respondents representing academia, consultants, clients, and others. Survey questions focused on perceptions and experiences related to inputs to decisions and decision processes, as well as remediation goal setting and outcomes. The most common remediation objective cited was short‐term interim measures and the least common was no further action (NFA) with clean closure. NFA was also sparingly achieved: 33% of respondents reported zero NFA closures in their career, and an overall 15% to 20% NFA closure rate was reported among more experienced respondents. Data inputs were ranked most important to decisions, while the decision process itself was ranked lowest. Intuition‐based decision methods such as asking for a trusted opinion, rules of thumb, and meetings were all used at last twice as often as decision analysis such as discounted cash flow or probabilistic analysis. Analysis of survey responses showed that cognitive biases, including overconfidence effect and intuition bias, are present to some extent in remediation decision‐making. Practitioners are advised to be mindful of the decision‐making processes they apply, and to incorporate elements of both intuition and decision analysis, as appropriate to the decisions being made.
Physiotherapist inter‐rater reliability of the Haemophilia Early Arthropathy Detection with Ultrasound protocol
Authors: Stephensen D. , Classey S. , Harbidge H. , Patel V. , Taylor S. , Wells A. 
Published: March 2018

IntroductionPrevention of arthropathy is the major goal of haemophilia treatment, and early detection of the first signs of joint damage is important so that prevention strategies can be initiated to limit physical disability and improve quality of life.AimThe aim of this study was to determine the inter‐rater repeatability of the HEAD‐US protocol when performed by haemophilia physiotherapists.MethodsSixty‐three joints (21 elbows, 21 knees and 21 ankles) were examined in 21 patients (mean age; 29.14 ± 10.09 years) according to the HEAD‐US protocol by four of six physiotherapists blinded to clinical information. Inter‐rater repeatability was evaluated by comparing the concordance of scores between the different clinicians using weighted Kappa (κw) statistics and 95% confidence intervals.ResultsSubstantial agreement was found when evaluating synovial hypertrophy (κw = 0.69), articular cartilage (κw = 0.60) and bone (κw = 0.74). Near perfect repeatability (κw > 0.80) was found when scoring synovitis profiles of the elbow joint and bone profiles of the knee joint. Repeatability was moderate for scoring synovitis and articular cartilage profiles of the ankle joint. A moderate correlation between HEAD‐US and HJHS was found for the elbow and ankle joint and a strong correlation for the knee joint. Discordance between clinical and ultrasound examination was 19.30%.ConclusionOverall, we found repeatability of the HEAD‐US protocol was good when performed by physiotherapists, and our results support the emerging view that US imaging complements the physical examination when screening and monitoring joint health of people with haemophilia at the point of care.
HETEROGENEITY AND THE PUBLIC SECTOR WAGE POLICY
Authors: Gomes Pedro 
Published: March 2018

AbstractA model with search and matching frictions and heterogeneous workers was established to evaluate a reform of the public sector wage policy in steady state. The model was calibrated to the U.K. economy based on Labour Force Survey data. A review of the pay received by all public sector workers to align the distribution of wages with the private sector reduces steady‐state unemployment by 1.4 percentage points.
An emerging transnational industrial relations? Exploring the prospects for cross‐border labour bargaining
Authors: LUTERBACHER Urs , PROSSER Andrew , PAPADAKIS Konstantinos 
Published: March 2018

AbstractGlobal union federations (GUFs) and multinational enterprises (MNEs) have been concluding “international framework agreements” (IFAs) to protect their interests amidst the globalizing economic landscape. By modelling the underlying bargaining processes, the authors show that IFAs can be expected when both sides exhibit risk aversion, although the agreement will favour the less risk‐averse side. Since globalization has created fewer vulnerabilities for MNEs than for GUFs, IFAs have so far typically delivered only minimal benefits for labour. But this should change in the future if strengthened transnational union capacities and abilities to threaten MNEs with reputational costs bring greater equalization of attitudes towards risk.
Beyond trees: Biogeographical regionalization of tropical Africa
Authors: Droissart Vincent , Dauby Gilles , Hardy Olivier J. , Deblauwe Vincent , Harris David J. , Janssens Steven , Mackinder Barbara A. , Blach‐Overgaard Anne , Sonké Bonaventure , Sosef Marc S. M. , Stévart Tariq , Svenning Jens‐Christian , Wieringa Jan J. , Couvreur Thomas L. P. 
Published: March 2018

AbstractAimTo delineate bioregions in tropical Africa and determine whether different plant growth forms (trees, terrestrial herbs, lianas and shrubs) display the same pattern of regionalization, diversity and endemism as the whole flora.LocationTropical Africa (excl. Madagascar), from 20° N to 25° S.TaxonVascular plants.MethodsAnalyses were based on occurrences of 24,719 vascular plant species distributed across tropical Africa extracted from the RAINBIO database. The majority of species (93%) were classified into four growth forms: terrestrial herbs, trees, shrubs and lianas. Biogeographical regions (bioregions) were delimited using a bipartite network clustering approach on the whole dataset and then separately for each growth form. Relationships among bioregions were investigated using non‐metric multidimensional scaling ordination, flora nestedness and endemism patterns.ResultsAnalyses of the whole dataset identified 16 bioregions and 11 transition zones. These were congruent with most of the currently recognized phytogeographical classifications, and also highlighted previously under‐recognized bioregions. Bioregion endemism rates were lower and species richness higher when compared to estimates from the White/Association pour l'Etude Taxonomique de la Flore d'Afrique Tropicale (AETFAT) classification. Analysed separately, plant growth forms showed contrasting geographical patterns. Bioregionalization was better resolved for closed forest types using trees and lianas and for open vegetation types using terrestrial herbs, while shrubs showed good discriminative power in all vegetation types.Main conclusionsWe show that distribution patterns based on solely trees are not sufficient to define floristic bioregions in tropical Africa. Analyses of spatial patterns using different growth forms are complementary, likely reflecting different evolutionary processes and ecological relationships. The contribution of growth forms to delimit geographical floristic patterns across tropical Africa is of critical importance for land use planning and management, and for selecting priority conservation areas.
Automatic Item Generation: A More Efficient Process for Developing Mathematics Achievement Items?
Authors: Embretson Susan E. , Kingston Neal M. 
Published: March 2018

AbstractThe continual supply of new items is crucial to maintaining quality for many tests. Automatic item generation (AIG) has the potential to rapidly increase the number of items that are available. However, the efficiency of AIG will be mitigated if the generated items must be submitted to traditional, time‐consuming review processes. In two studies, generated mathematics achievement items were subjected to multiple stages of qualitative review for measuring the intended skills, followed by empirical tryout in operational testing. High rates of success were found. Further, items generated from the same item structure had predictable psychometric properties. Thus, the feasibility of a more limited and expedient review processes was supported. Additionally, positive results were obtained on measuring the same skills from item structures with reduced cognitive complexity.
The mind‐brain gap and the neuroscience‐psychiatry gap
Authors: Telles‐Correia Diogo 
Published: March 2018

AbstractA problem underlying the mind brain gap is the complex integration among the disciplines involved in it: neurosciences, clinical psychiatry and psychology, and philosophy of science. Research in neurosciences and clinical psychiatry requires a positioning in relation to some conceptual/philosophical aspects. These are related to the models of interrelationship of the brain and the mind, to explanatory approaches in psychiatry, and to conceptual issues such as dimensionality versus categories, symptoms versus disorders, and neurobiological correlates versus clinical determination of mental disorder. In this article, we try to address some of these issues that, if taken into account, could reduce the gap between psychiatrists and neuroscientists and turn the research in this area more profitable.
Somatoform disorder in primary care: The influence of co‐morbidity with anxiety and depression on health care utilization
Authors: Hüsing Paul , Löwe Bernd , Piontek Katharina , Shedden‐Mora Meike 
Published: March 2018

AbstractRationale, aims, and objectivesPatients with somatoform disorders are frequent attenders in primary and secondary care. While co‐morbid mental disorders, especially depression and anxiety, are frequently present, there is controversy on whether mental co‐morbidity leads to higher health care utilization (HCU). The present paper investigates the influence of co‐morbid depressive and anxiety disorders on primary, specialized somatic and mental HCU in primary care patients with somatoform disorders. Additionally, we investigated the predictive value of self‐rated health and illness perception on HCU.MethodsPatients in 19 primary care practices were screened with the Patient Health Questionnaire, and patients at high risk for somatoform disorders were assessed using the Composite International Diagnostic Interview. N = 71 patients with somatoform disorders were analysed. We analysed whether having one vs two co‐morbidities (depression and/or anxiety), self‐rated health, and illness perception were predictors for primary, specialized somatic and mental HCU using binominal and hierarchical regression analyses.ResultsHaving both co‐morbid depressive and anxiety disorder predicted higher primary HCU (IRR = 1.96, 95% CI, 1.30‐2.93), and increased the odds of being in mental health care (OR = 5.16, 95% CI, 1.10‐24.20), while only one co‐morbidity did not. No differences were found for specialized somatic HCU. Illness perception and self‐rated health did not predict HCU.ConclusionNot a single but only the presence of multiple co‐morbidities predicts primary and mental HCU in patients with somatoform disorder. Health care utilization might be essentially influenced by the associated psychological distress, which should be considered in treatment.
Lessons learnt from the epidemiology of Helicobacter pylori infection in Malaysia: JGHF Marshall and Warren Lecture 2017
Authors: Goh Khean‐Lee 
Published: March 2018

AbstractThe study of Helicobacter pylori in Malaysia has given several important insights into the epidemiology of the infection and pathogenesis of disease. Malaysia has a multiracial Asian population with three major Asian races living together—Malay, Chinese, and Indian. Races remain fairly distinct because of a paucity of interracial marriages. The “Racial Cohort Hypothesis” proposes that the infection occurs within racial groups rather than between. As such, the high prevalence among Indians (> 50%) and Chinese (40–50%) reflects the high prevalence in their countries of origin even though migration had taken place more than two generations before. The Malays have a comparatively low prevalence of about 10–20%. Despite the high prevalence of H. pylori, the Indians have a low gastric cancer incidence of less than 10 per 100 000 per year. This is in contrast to the Chinese who has an incidence in excess of 20 per 100 000 per year. We have called this the “Indian Enigma.” The reason for this enigma is unclear and is the result of interaction between bacterial virulence factors, host susceptibility, and environmental factors. Phylogenetically, Chinese bacterial strains are distinct from Indians and Malays and are predominantly hpEastAsia/hsp EAsia. CagA EPIYA motifs among Chinese belong predominantly to the more virulent ABD motif. There is no clear distinguishing profile among host genetic factors. Environmental factors particularly diet may play an important role. Indians consume chilies and curries, which may be gastro protective, whereas Chinese consume more preserved and salted foods, which are thought to be carcinogenic.