bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Evaluation of Single‐Well LNAPL Tracer Testing at Five Sites
Authors: Pennington Andrew , Smith Jonathon , Koons Brad , Divine Craig E.
Published: March 2018

Light nonaqueous phase liquid (LNAPL) tracer testing is a technique used to directly measure LNAPL flow in situ and evaluate LNAPL mobility and recoverability. The test method consists of adding a fluorescent oil‐soluble tracer to LNAPL within a well, isolating small volumes of LNAPL with known tracer concentrations for use as in‐well calibration standards, and measuring the rate of tracer concentration decline in the well over time. The test measures LNAPL flux through the well, which is directly related to LNAPL mobility and recoverability in the surrounding formation. Test results for a total of 29 wells at five sites are presented. Results from LNAPL tracer testing were comparable to results obtained through other methods, and the method offers a time‐averaged result measured over a relatively long period, in ambient conditions, and reflects the influences of heterogeneity and hydraulic changes. In some cases, tracer concentration decline followed unexpected patterns, and these data have led to a better understanding of test assumptions, mechanisms influencing tracer distribution, and options to improve test execution and data interpretation. Method improvements developed over the course of the field studies included refinement of pre‐test screening of LNAPL fluorescence and improvements to measurement equipment. Overall, the field studies confirmed the technical validity and usefulness of the LNAPL tracing technique to support LNAPL mobility and recoverability assessments.
Characterizing Groundwater Flow in Monitoring Wells by Altering Dissolved Oxygen
Authors: Vitale Sarah A. , Robbins Gary A.
Published: March 2018

In this study, the dissolved oxygen (DO) alteration method (Chlebica and Robbins 2013) is used to evaluate the patterns of flow into and vertically within shallow screened monitoring wells. The method entails bubbling air into a well, followed by conducting DO profiles with time. Tests were conducted in six standard 2" (5 cm) polyvinyl chloride shallow screened monitoring wells at four test sites in Storrs, Connecticut. Test sites vary in formation permeability, flow patterns, and nearby geographic features influencing flow. The method provides a means for groundwater flow characterization and potentially improved interpretation of contamination sampling results in the absence of detailed three‐dimensional hydrogeologic information.
Syringe‐Tip Filters May Contain the Artificial Sweetener Saccharin
Authors: Spoelstra John , Roy James W. , Brown Susan J.
Published: March 2018

The presence of artificial sweeteners in environmental samples is increasingly used to detect wastewater (and recently landfill leachate) in rivers, lakes and groundwater. Through routine laboratory quality assurance/quality control procedures, it was discovered that some syringe‐tip filters leach saccharin when used to process water samples. We subsequently tested several brands of filters to determine if they leached any of the four common artificial sweeteners analyzed in environmental samples, acesulfame, saccharin, cyclamate, and sucralose. Of the six types of filters tested, only one brand was a source of artificial sweeteners and the only artificial sweetener found was saccharin. The source of the saccharin in the filters is unknown but it is likely the result of some step in the manufacturing process. The saccharin was typically removed from these filters using a distilled water rinse of 13 mL or less. As a precaution, filters should be pre‐tested for the presence of saccharin and/or filters should be flushed with distilled water or sample prior to the collection of water samples for artificial sweetener analyses.
Effect of Biofuels on Biodegradation of Benzene and Toluene at Gasoline Spill Sites
Authors: Wilson John T. , Adair Cherri , White Hal , Howard Robert L.
Published: March 2018

The risk that benzene and toluene from spills of gasoline will impact drinking water wells is largely controlled by the natural anaerobic biodegradation of benzene and toluene. Benzene and toluene, as well as ethanol and other biofuels, are degraded under anaerobic conditions to the same pool of degradation products. Biodegradation of biofuels may produce concentrations of degradation products that make the thermodynamics for degradation of benzene and toluene infeasible under methanogenic conditions and produce larger plumes of benzene and toluene. This study evaluated the concentrations of fuel alcohols that are necessary to inhibit the anaerobic degradation of benzene and toluene under methanogenic conditions. At two ethanol spill sites, concentrations of ethanol greater ≥42 mg/L inhibited the anaerobic degradation of toluene. The pH and concentrations of acetate, dissolved inorganic carbon, and molecular hydrogen were used to calculate the Gibbs free energy for the biodegradation of toluene. In general, the anaerobic biodegradation of toluene was not thermodynamically feasible in water with ≥42 mg/L ethanol. In a microcosm study, when the concentrations of ethanol were ≥14 mg/L or the concentrations of n‐butanol were ≥16 mg/L, the biodegradation of the alcohols consistently produced concentrations of hydrogen, dissolved inorganic carbon, and acetate that would preclude natural anaerobic biodegradation of benzene and toluene by syntrophic organisms. In contrast, iso‐butanol and n‐propanol only occasionally produced conditions that would preclude the biodegradation of benzene and toluene.
Optimal Decision Making Algorithm for Managed Aquifer Recharge and Recovery Operation Using Near Real‐Time Data: Benchtop Scale Laboratory Demonstration
Authors: Drumheller Zachary , Smits Kathleen M. , Illangasekare Tissa H. , Regnery Julia , Lee Jonghyun , Kitanidis Peter K.
Published: March 2018

Aquifers show troubling signs of irreversible depletion as climate change, population growth, and urbanization lead to reduced natural recharge rates and overuse. One strategy to sustain the groundwater supply is to recharge aquifers artificially with reclaimed water or stormwater via managed aquifer recharge and recovery (MAR) systems. Unfortunately, MAR systems remain wrought with operational challenges related to the quality and quantity of recharged and recovered water stemming from a lack of data‐driven, real‐time control. This paper presents a laboratory scale proof‐of‐concept study that demonstrates the capability of a real‐time, simulation‐based control optimization algorithm to ease the operational challenges of MAR systems. Central to the algorithm is a model that simulates water flow and transport of dissolved chemical constituents in the aquifer. The algorithm compensates for model parameter uncertainty by continually collecting data from a network of sensors embedded within the aquifer. At regular intervals the sensor data is fed into an inversion algorithm, which calibrates the uncertain parameters and generates the initial conditions required to model the system behavior. The calibrated model is then incorporated into a genetic algorithm that executes simulations and determines the best management action, for example, the optimal pumping policy for current aquifer management goals. Experiments to calibrate and validate the simulation‐optimization algorithm were conducted in a small two‐dimensional synthetic aquifer under both homogeneous and heterogeneous packing configurations. Results from initial experiments validated the feasibility of the approach and suggested that our system could improve the operation of full‐scale MAR facilities.
Integrity of Clay Till Aquitards to DNAPL Migration: Assessment Using Current and Emerging Characterization Tools
Authors: Fjordbøge Annika S. , Janniche Gry S. , Jørgensen Torben H. , Grosen Bernt , Wealthall Gary , Christensen Anders G. , Kerrn‐Jespersen Henriette , Broholm Mette M.
Published: March 2018

Field investigations were carried out to determine the occurrence of tetrachloroethene (PCE) dense nonaqueous phase liquid (DNAPL), the source zone architecture and the aquitard integrity at a 30‐ to 50‐year old DNAPL release site. The DNAPL source zone is located in the clay till unit overlying a limestone aquifer. The DNAPL source zone architecture was investigated through a multiple‐lines‐of‐evidence approach using various characterization tools; the most favorable combination of tools for the DNAPL characterization was geophysical investigations, membrane interface probe, core subsampling with quantification of chlorinated solvents, hydrophobic dye test with Sudan IV, and Flexible Liner Underground Technologies (FLUTe) NAPL liners with activated carbon felt (FACT). While the occurrence of DNAPL was best determined by quantification of chlorinated solvents in soil samples supported by the hydrophobic dye tests (Sudan IV and NAPL FLUTe), the conceptual understanding of source zone architecture was greatly assisted by the indirect continuous characterization tools. Although mobile or high residual DNAPL (S
t > 1%) only occurred in 11% of the source zone samples (intact cores), they comprised 86% of the total PCE mass. The dataset, and associated data analysis, supported vertical migration of DNAPL through fractures in the upper part of the clay till, horizontal migration along high permeability features around the redox boundary in the clay till, and to some extent vertical migration through the fractures in the reduced part of the clay till aquitard to the underlying limestone aquifer. The aquitard integrity to DNAPL migration was found to be compromised at a thickness of reduced clay till of less than 2 m.
Integrated Plume Treatment Using Persulfate Coupled with Microbial Sulfate Reduction
Authors: Shayan Mahsa , Thomson Neil R. , Aravena Ramon , Barker James F. , Madsen Eugene L. , Marchesi Massimo , DeRito Christopher M. , Bouchard Daniel , Buscheck Tim , Kolhatkar Ravi , Daniels Eric J.
Published: March 2018

The integration or sequential use of different remediation technologies, also referred to as a combined remedy, has become an emerging strategy for the treatment of contaminated sites. Coupling chemical oxidation using persulfate with enhanced bioremediation (EBR) under sulfate reducing conditions is a plausible combined remedy. To characterize the role of the mass removal processes (e.g., chemical oxidation vs. sulfate reduction) and to quantify the impact of persulfate on indigenous microbial processes in a combined persulfate/EBR treatment system, a pilot‐scale field experiment was conducted in a 24‐m long sheet pile‐walled gate over a period of approximately 400 d. After dissolved benzene, toluene, and o‐xylene (BTX) quasi steady‐state plumes were developed, two persulfate injection episodes were performed 10 d apart to create a chemical oxidation (ChemOx) zone. High‐resolution monitoring was conducted to observe the migration of the ChemOx zone and transition into an EBR zone. Mass loss estimates and geochemical indicators were used to identify the distinct transition between the ChemOx and enhanced biological reactive zones. Compound specific isotope analysis (CSIA) was used to distinguish the dominant mass removal process, and to investigate the occurrence of microbial sulfate reduction. BTX metabolites and reverse‐transcriptase quantitative polymerase chain reaction analyses of expressed biodegradation genes (as mRNA) were also used to characterize the response of indigenous microorganisms (especially sulfate‐reducing bacteria) to the added persulfate. Multiple lines of evidence supported the conclusion that chemical oxidation was the dominant mass removal process in the vicinity of the injection zone, while enhanced biodegradation dominated BTX degradation in the downgradient portions of the system. The CSIA and supporting molecular biological data were critical in documenting temporally and spatially distinctive zones in this system that were dominated by either chemical‐oxidation or anaerobic‐biodegradation processes. Initially, persulfate had an inhibitory impact on the activity of the indigenous microbial community, but this was followed by a substantial rebound of microbial activity to above baseline levels. The results from this investigation demonstrate that the suite of diagnostic tools employed can be used to distinguish between chemical oxidation using persulfate and the subsequent effects of the produced sulfate.
Carbon and Hydrogen Isotope Fractionation of Benzene, Toluene, and o‐Xylene during Chemical Oxidation by Persulfate
Authors: Solano Felipe M. , Marchesi Massimo , Thomson Neil R. , Bouchard Daniel , Aravena Ramon
Published: March 2018

Experiments were performed to investigate the carbon and hydrogen isotope fractionation of benzene, toluene, and o‐xylene (BTX) during chemical oxidation by unactivated persulfate at two concentrations (8 and 20 g/L). Carbon enrichment (ϵC) values of −1.7 ± 0.1‰ for benzene, −0.64 ± 0.1‰ for toluene and −0.36 ± 0.04‰ for o‐xylene were obtained. No significant hydrogen enrichment (ϵH) was observed for benzene, while the hydrogen enrichment for toluene and o‐xylene were −20 ± 3‰ and −23 ± 2‰, respectively. The dual isotope plot (Δδ13C vs. Δδ2H) for benzene and o‐xylene revealed a distinct fractionation trend compared to the majority of the biodegradation data compiled from the literature; however, no unique trend was observed for toluene. The significant carbon and/or hydrogen enrichment, and the distinct trend observed on the dual isotope plot suggest that compound specific isotope analysis (CSIA) can potentially be used to monitor the chemical oxidation of BTX by persulfate, and to distinguish treatment areas where persulfate or biodegradation reactions are occurring for benzene and o‐xylene.
Does Pumping Volume Affect the Concentration of Micropollutants in Groundwater Samples?
Authors: van Driezum Inge H. , Derx Julia , Saracevic Ernis , Kirschner Alexander K.T. , Sommer Regina , Farnleitner Andreas H. , Blaschke Alfred Paul
Published: March 2018

Information on concentrations of micropollutants (such as pharmaceuticals, pesticides, and industrial chemicals) in most highly dynamic riverbank filtration (RBF) systems is lacking, in contrast to data on standard chemical parameters. Sampling protocols have thus far been based on the stabilization of standard chemical parameters in relatively pristine environments. To determine whether groundwater samples for micropollutant analysis can be taken at a similar pumping volume as samples for testing standard chemical parameters in both environments, three groundwater monitoring wells in an RBF system were sampled at two points in time (after pumping of 3 well volumes and after pumping of 15 well volumes). Micropollutant concentrations were not significantly different between the two sampling points; therefore, appropriate samples can be drawn after pumping 3 well volumes. For a specific microbiological parameter (leucin incorporation), a statistically significant difference was found.
Phytoscreening for Vinyl Chloride in Groundwater Discharging to a Stream
Authors: Ottosen Cecilie B. , Rønde Vinni , Trapp Stefan , Bjerg Poul L. , Broholm Mette M.
Published: March 2018

This study applies an optimized phytoscreening method to locate a chlorinated ethene plume discharging into a stream. To evaluate the conditions most suitable for successful phytoscreening, trees along the stream bank were monitored through different seasons with different environmental conditions and hence different uptake/loss scenarios. Vinyl chloride (VC) as well as cis‐dichloroethylene (cis‐DCE), trichloroethylene (TCE), and tetrachloroethylene (PCE) were detected in the trees, documenting that phytoscreening is a viable method to locate chlorinated ethene plumes, including VC, discharging to streams. The results reveal, that phytoscreening for VC is more sensitive to environmental conditions affecting transpiration than for the other chlorinated ethenes detected. Conditions leading to higher groundwater uptake by transpiration than contaminant loss by diffusion from the tree trunks are optimal (e.g., low relative humidity, plentiful hours of sunshine and an intermediate air temperature). Additionally, low precipitation prior to the sampling event is beneficial, as uptake of infiltrating precipitation dilutes the concentration in the trees. All chlorinated ethenes were sensitive to dilution by clean precipitation and in some months, this resulted in no detection of contaminants in the trees at all. Under optimal environmental conditions the tree cores allowed detection of chlorinated solvents and their metabolites in the underlying groundwater. Whereas, for less ideal conditions there was a risk of no detection of the more volatile VC. This study is promising for the future applicability of phytoscreening to locate shallow groundwater contamination with the degradation products of chlorinated solvents.
Soil Gas Sampling for 1,4‐Dioxane during Heated Soil Vapor Extraction
Authors: Burris David R. , Dahlen Paul R. , Hinchee Robert E.
Published: March 2018

Soil gas sampling for 1,4‐dioxane at elevated soil temperatures, such as those experienced during in‐situ thermal treatment, has the potential to yield low results due to condensation of water vapor in the ambient temperature sampling vessel and the partitioning of 1,4‐dioxane into that condensate. A simple vapor/condensate sampling apparatus was developed to collect both condensate and vapor samples to allow for determination of a reconstituted effective soil gas concentration for 1,4‐dioxane. Results using the vapor/condensate sampling apparatus during a heated air injection SVE field demonstration are presented, along with those of a comparable laboratory system. Substantial 1,4‐dioxane mass was found in the condensate in both the lab and field (as high as ~50% in field). As soil temperatures increased, less 1,4‐dioxane mass was detected in field condensate samples than expected based on laboratory experiments. Extraction well effluent sampling at the wellhead by direct vapor canister sampling provided erratic results (several biased low by a factor of 5 or more) compared to those of the vapor/condensate apparatus. Direct vapor canister sampling of extraction well effluent after the air‐water separator, however, provided results reasonably comparable (within 35%) to those using the vapor/condensate apparatus at the wellhead. Soil gas sampling at elevated temperatures using the vapor/condensate apparatus alleviates potential low sampling bias due to condensation.
Quantification of TCE Co‐Oxidation in Groundwater Using a 14C–Assay
Authors: Mills James C. , Wilson John T. , Wilson Barbara H. , Wiedemeier Todd H. , Freedman David L.
Published: March 2018

Bacteria that degrade natural organic matter in groundwater contain oxygenase enzymes that can co‐oxidize trichloroethene (TCE). This degradation pathway is promising for large dilute plumes, but its evaluation is limited because the density of the bacteria with oxygenase enzymes has not been correlated to field scale rates of degradation. A 14C–TCE assay was developed to determine pseudo first‐order rate constants for the aerobic co‐oxidation of TCE in groundwater. The assay involved incubating 14C–TCE in samples of groundwater contained in 160 mL serum bottles, and monitoring the accumulation of radiolabel in degradation products. A first‐order rate constant for co‐oxidation was extracted from the rate of accumulation of 14C in products, accounting for volumetric changes in the serum bottles due to sampling and subsequent changes to the distribution of TCE between the aqueous and gaseous phases. Of the groundwater samples evaluated from 19 wells at five sites, eight samples at three sites had 14C product accumulation rates that exceeded the accumulation rate in filter‐sterilized groundwater controls. First‐order rate constants ranged from 2.65 to 0.0066 year−1, which is equivalent to half‐lives of 0.26 to 105 years. Groundwater samples from a few of the wells in which co‐oxidation occurred had volatile organic contaminants in addition to TCE; their presence may have induced the oxygenase enzymes that are needed for TCE co‐oxidation. 14CO2 represented ~37% to 97% of the 14C products that accumulated; the balance of the products was soluble and non‐volatile.
Assessing mental health and service needs among refugees in Malaysia
Authors: Shaw Stacey A. , Pillai Veena , Ward Kaitlin P.
Published: March 2018

Refugees in Malaysia often experience economic insecurity and poverty, poor health, poor mental wellbeing and limited legal rights. Using a survey with quantitative measures and open‐ended questions, we assessed socio‐demographic characteristics, mental health (RHS‐15), and service needs, including interest in group support services, among 86 Dari‐ and Arabic‐speaking refugees living in Kuala Lumpur. High levels of emotional distress were found, as nearly all participants scored positive for distress and average scores were 2.5 times above the cut‐off signifying distress. Distress scores did not vary based on most factors examined, although being married was associated with lower levels of distress. All but one participant expressed interest in participating in a support group. Barriers to potential participation included childcare, sickness and transportation. Additional mental health and social supports are needed among refugees residing in Malaysia.

Key Practitioner Message: • Emotional distress is high among Dari‐ and Arabic‐speaking refugees sampled in Malaysia; • Participants expressed strong interest in accessing supportive mental health services, including group supports.
The scars of youth: Effects of early‐career unemployment on future unemployment experience
Authors: SCHMILLEN Achim , UMKEHRER Matthias
Published: March 2018

Does early‐career unemployment cause future unemployment? The authors approach this question using German administrative matched employer–employee data that track almost 700,000 individuals over 24 years. Instrumenting early‐career unemployment with firm‐specific labour demand shocks, they find significant and long‐lasting “scarring effects”. In the mean, each additional day of unemployment during the first eight years on the labour market increases unemployment in the following 16 years by half a day. However, quantile regressions show that the scarring effects are much stronger for individuals who already suffer from lengthy and repeated spells of unemployment.
Molecular control of B‐cell homeostasis in health and malignancy
Authors: Garcillán Beatriz , Figgett William A , Infantino Simona , Lim Ee Xin , Mackay Fabienne
Published: March 2018

Altered B‐cell homeostasis underlies a wide range of pathologies, from cancers to autoimmunity and immunodeficiency. The molecular safeguards against those disorders, which also allow effective immune responses, are therefore particularly critical. Here, we review recent findings detailing the fine control of B‐cell homeostasis, during B‐cell development, maturation in the periphery and during activation and differentiation into antibody‐producing cells.
Just Before I Recognize Myself: The Role of Featural and Multisensory Cues Leading up to Explicit Mirror Self‐Recognition
Authors: Filippetti Maria Laura , Tsakiris Manos
Published: March 2018

Leading up to explicit mirror self‐recognition, infants rely on two crucial sources of information: the continuous integration of sensorimotor and multisensory signals, as when seeing one's movements reflected in the mirror, and the unique facial features associated with the self. While visual appearance and multisensory contingent cues may be two likely candidates of the processes that enable self‐recognition, their respective contribution remains poorly understood. In this study, 18‐month‐old infants saw side‐by‐side pictures of themselves and a peer, which were systematically and simultaneously touched on the face with a hand. While watching the stimuli, the infant's own face was touched either in synchrony or out of synchrony and their preferential looking behavior was measured. Subsequently, the infants underwent the mirror‐test task. We demonstrated that infants who were coded as nonrecognizers at the mirror test spent significantly more time looking at the picture of their own face compared to the other‐face, irrespective of whether the multisensory input was synchronous or asynchronous. Our results suggest that right before the onset of mirror self‐recognition, featural information about the self might be more relevant in the process of recognizing one's face, compared to multisensory cues.
Enterovirus D‐68 in children presenting for acute care in the hospital setting
Authors: Savage Timothy J. , Kuypers Jane , Chu Helen Y. , Bradford Miranda C. , Buccat Anne Marie , Qin Xuan , Klein Eileen J. , Jerome Keith R. , Englund Janet A. , Waghmare Alpana
Published: March 2018

Background

Severe respiratory disease associated with enterovirus D68 (EV‐D68) has been reported in hospitalized pediatric patients. Virologic and clinical characteristics of EV‐D68 infections exclusively in patients presenting to a hospital Emergency Department (ED) or urgent care have not been well defined.

Methods

Mid‐nasal swabs from pediatric patients with respiratory symptoms presenting to the ED or urgent care were evaluated using a commercial multiplex PCR platform. Specimens positive for rhinovirus/enterovirus (HRV/EV) were subsequently tested using real‐time reverse‐transcriptase PCR for EV‐D68. The PCR cycle threshold (CT) was used as a viral load proxy. Clinical outcomes were compared between patients with EV‐D68 and patients without EV‐D68 who tested positive for HRV/EV.

Results

From August to December 2014, 511 swabs from patients with HRV/EV were available. EV‐D68 was detected in 170 (33%) HRV/EV‐positive samples. In multivariable models adjusted for age and underlying asthma, patients with EV‐D68 were more likely to require hospitalization for respiratory reasons (odds ratio (OR): 3.11, CI: 1.85‐5.25), require respiratory support (OR: 1.69, CI: 1.09‐2.62), have confirmed/probable lower respiratory tract infection (LRTI; OR: 3.78, CI: 2.03‐7.04), and require continuous albuterol or steroids (OR: 3.91, CI: 2.22‐6.88 and OR: 4.73, CI: 2.65‐8.46, respectively). Higher EV‐D68 viral load was associated with need for respiratory support and LRTI in multivariate models.

Conclusions

Among pediatric patients presenting to the ED or urgent care, EV‐D68 causes more severe disease than non‐EV‐D68 HRV/EV independent of underlying asthma. High viral load was associated with worse clinical outcomes. Rapid and quantitative viral testing may help identify and risk stratify patients.
X‐ray photoelectron spectroscopy analysis of Ge–Sb–Se pulsed laser deposited thin films
Authors: Baudet Emeline , Cardinaud Christophe , Boidin Rémi , Girard Aurélie , Gutwirth Jan , Němec Petr , Nazabal Virginie
Published: March 2018

Pulsed laser deposition was used to prepare amorphous thin films from (GeSe2)100−x(Sb2Se3)x system (x = 0, 5, 10, 20, 30, 40, 50, and 60). From a wide variety of chalcogenide glass‐forming systems, Ge–Sb–Se one, especially in thin films form, already proved to offer a great potential for photonic devices such as chemical sensors. This system has a large glass‐forming region which gives the possibility to adjust the chemical composition of the glasses according to required physical characteristics. The chemical composition of fabricated thin films was analyzed via X‐ray photoelectron spectroscopy (XPS) and compared to energy dispersive spectroscopy (EDS) data. The results of both techniques agree well: a small deficiency in chalcogen element and an excess of antimony was found. The structure of as‐deposited thin films has been investigated by XPS. The presence of the two main structural units, [GeSe4] and [SbSe3] proposed by Raman scattering spectroscopy data analysis, was confirmed by XPS. Moreover, XPS core level spectra analysis revealed the presence of M–M bonds (M = Ge, Sb) in (Ge,Sb)–Ge–(Se)3 and (Ge,Sb)–Sb–(Se)2 entities that could correspond to Ge‐based tetrahedra and Sb‐based pyramids where one of its Se atoms at corners is substituted by Ge or Sb ones. The content of depicted M–M bonds tends to increase with introduction of antimony in the amorphous network of as‐deposited thin films from x = 0 to x = 40 and then it decreases. XPS analysis of as‐deposited thin films shows also the presence of the (Ge,Sb)–Se–(Ge,Sb) and Se–Se–(Ge,Sb) entities.
The role of emotions in predicting sperm and egg donation
Authors: Shepherd Lee , Kardzhieva Dimana , Bussey Lauren , Lovell Brian
Published: March 2018

Sperm and egg donation allows people who cannot have children naturally to become parents. However, in many countries there is a shortage of donors. Therefore, it is important to assess the factors that influence donation. Across two studies, we assessed the role of social‐cognitive and emotional factors in promoting and deterring sperm and egg donation. Study 1 (N = 138 men) found that feeling anxiety toward discovering a fertility problem and pride positively predicted sperm donation intention and information seeking behavior. By contrast, feeling anxiety toward the process of donation negatively predicted sperm donation intention and information seeking behavior. Study 2 (N = 193 women) found that pride positively and the anxiety toward the process negatively predicted egg donation intentions, but not information seeking behavior. These results suggest that it is important to consider the role of emotions in motivating and deterring people from becoming a sperm and egg donor.
The transcription factor Dach1 is essential for podocyte function
Authors: Endlich Nicole , Kliewe Felix , Kindt Frances , Schmidt Katharina , Kotb Ahmed M. , Artelt Nadine , Lindenmeyer Maja T. , Cohen Clemens D. , Döring Franziska , Kuss Andreas W. , Amann Kerstin , Moeller Marcus J. , Kabgani Nazanin , Blumenthal Antje , Endlich Karlhans
Published: March 2018

Dedifferentiation and loss of podocytes are the major cause of chronic kidney disease. Dach1, a transcription factor that is essential for cell fate, was found in genome‐wide association studies to be associated with the glomerular filtration rate. We found that podocytes express high levels of Dach1 in vivo and to a much lower extent in vitro. Parietal epithelial cells (PECs) that are still under debate to be a type of progenitor cell for podocytes expressed Dach1 only at low levels. The transfection of PECs with a plasmid encoding for Dach1 induced the expression of synaptopodin, a podocyte‐specific protein, demonstrated by immunocytochemistry and Western blot. Furthermore, synaptopodin was located along actin fibres in a punctate pattern in Dach1‐expressing PECs comparable with differentiated podocytes. Moreover, dedifferentiating podocytes of isolated glomeruli showed a significant reduction in the expression of Dach1 together with synaptopodin after 9 days in cell culture. To study the role of Dach1 in vivo, we used the zebrafish larva as an animal model. Knockdown of the zebrafish ortholog Dachd by morpholino injection into fertilized eggs resulted in a severe renal phenotype. The glomeruli of the zebrafish larvae showed morphological changes of the glomerulus accompanied by down‐regulation of nephrin and leakage of the filtration barrier. Interestingly, glomeruli of biopsies from patients suffering from diabetic nephropathy showed also a significant reduction of Dach1 and synaptopodin in contrast to control biopsies. Taken together, Dach1 is a transcription factor that is important for podocyte differentiation and proper kidney function.
Precision medicine in diabetes prevention, classification and management
Authors: Xie Fangying , Chan Juliana CN , Ma Ronald CW
Published: March 2018

Diabetes has become a major burden of healthcare expenditure. Diabetes management following a uniform treatment algorithm is often associated with progressive treatment failure and development of diabetic complications. Recent advances in our understanding of the genomic architecture of diabetes and its complications have provided the framework for development of precision medicine to personalize diabetes prevention and management. In the present review, we summarized recent advances in the understanding of the genetic basis of diabetes and its complications. From a clinician's perspective, we attempted to provide a balanced perspective on the utility of genomic medicine in the field of diabetes. Using genetic information to guide management of monogenic forms of diabetes represents the best‐known examples of genomic medicine for diabetes. Although major strides have been made in genetic research for diabetes, its complications and pharmacogenetics, ongoing efforts are required to translate these findings into practice by incorporating genetic information into a risk prediction model for prioritization of treatment strategies, as well as using multi‐omic analyses to discover novel drug targets with companion diagnostics. Further research is also required to ensure the appropriate use of this information to empower individuals and healthcare professionals to make personalized decisions for achieving the optimal outcome.
Phenotypic integration in an extended phenotype: among‐individual variation in nest‐building traits of the alfalfa leafcutting bee (Megachile rotundata)
Authors: Royauté Raphaël , Wilson Elisabeth S. , Helm Bryan R. , Mallinger Rachel E. , Prasifka Jarrad , Greenlee Kendra J. , Bowsher Julia H.
Published: March 2018

Structures such as nests and burrows are an essential component of many organisms’ life‐cycle and require a complex sequence of behaviours. Because behaviours can vary consistently among individuals and be correlated with one another, we hypothesized that these structures would (1) show evidence of among‐individual variation, (2) be organized into distinct functional modules and (3) show evidence of trade‐offs among functional modules due to limits on energy budgets. We tested these hypotheses using the alfalfa leafcutting bee, Megachile rotundata, a solitary bee and important crop pollinator. Megachile rotundata constructs complex nests by gathering leaf materials to form a linear series of cells in pre‐existing cavities. In this study, we examined variation in the following nest construction traits: reproduction (number of cells per nest and nest length), nest protection (cap length and number of leaves per cap), cell construction (cell size and number of leaves per cell) and cell provisioning (cell mass) from 60 nests. We found a general decline in investment in cell construction and provisioning with each new cell built. In addition, we found evidence for both repeatability and plasticity in cell provisioning with little evidence for trade‐offs among traits. Instead, most traits were positively, albeit weakly, correlated (r ~ 0.15), and traits were loosely organized into covarying modules. Our results show that individual differences in nest construction are detectable at a level similar to that of other behavioural traits and that these traits are only weakly integrated. This suggests that nest components are capable of independent evolutionary trajectories.
Correlated evolution of thermal niches and functional physiology in tropical freshwater fishes
Authors: Culumber Zachary W. , Tobler Michael
Published: March 2018

The role of ecology in phenotypic and species diversification is widely documented. Nonetheless, numerous nonadaptive processes can shape realized niches and phenotypic variation in natural populations, complicating inferences about adaptive evolution at macroevolutionary scales. We tested for evolved differences in thermal tolerances and their association with the realized thermal niche (including metrics describing diurnal and seasonal patterns of temperature extremes and variability) across a genus of tropical freshwater fishes reared in a standardized environment. There was limited evolution along the thermal niche axis associated with variation in maximum temperature and in upper thermal limits. In contrast, there was considerable diversification along the first major axis of the thermal niche associated with minimum temperatures and in lower thermal limits. Across our adaptive landscape analyses, 70% of species exhibited evidence of divergence in thermal niches. Most importantly, the first two major axes of thermal niche variation were significantly correlated with variation in lower thermal limits. Our results indicate adaptation to divergent thermal niches and adaptive evolution of related functional traits, and highlight the importance of divergence in lower thermal limits for the evolution of tropical biodiversity.
Facing financialization: The divergent mutations of agricultural cooperatives in postapartheid South Africa
Authors: Ducastel Antoine , Anseeuw Ward
Published: March 2018

This paper analyses the transformation of the South African (former) grain cooperatives since 1994. These entities played a key role in the institutional architecture of the apartheid regime, ensuring the domination of white commercial farmers over the sector. Within the framework of the deregulation of the economy and the agricultural sector, such entities faced transformations of modern capitalism, especially the growing power of financial actors and markets. Although white commercial farmers still largely retain these inherited structures, these companies are presently being targeted more and more by private takeovers and/or private equity deals. Based on two specific empirical examples of private equity deals affecting South African grain cooperatives, this paper describes this financialization process in practice, in particular by analysing the interaction between financial and agricultural actors and the alliances on the ground that determine its “success.” In doing so, it details the different trajectories of these (former) cooperatives, highlighting the resilience, mutation, and extinction of commercial agriculture in South Africa.
The Advertisement of Alcohol in Colonial and Post‐Colonial Times in Southern Nigeria
Authors: Okonkwo Uche Uwaezuoke
Published: March 2018

Until the arrival of Europeans to the coast of Africa, indigenous alcohol brands were heavily consumed. The arrival of Europeans with foreign alcohol brands came with heavy advertisement focusing on the idea of modernity. Although the people did not abandon indigenous consumption of alcohol, imported alcohol brands became a yardstick for measuring class and thus created a new form of identity not previously in existence.
Associations between informant ratings of personality disorder traits, self‐reports of personality, and directly observed behavior
Authors: Kaurin Aleksandra , Sauerberger Kyle S. , Funder David C.
Published: March 2018

Objective

Diagnoses of personality disorders (PD) must rely on judgments of observers—either clinicians or acquaintances—because personality disorders are primarily defined in terms of maladaptive interpersonal behavior. Little is known, however, about how closely acquaintances' judgments of PD traits relate to self‐reports of theoretically relevant Big Five traits or directly observed behavioral outcomes in interpersonal situations. The present study examines associations between judgments of the 10 PD traits provided by close acquaintances, self‐reports of PD‐relevant Big Five personality traits, and observed interpersonal behaviors across three different three‐person laboratory interactions (i.e., unstructured chat, cooperative task, competitive game).

Method

The sample consisted of 256 undergraduate students (130 females; Mage = 19.83, SD = 1.25). Four unacquainted observers independently rated participants' behaviors from video recordings.

Results

In line with previous work, informant reports of PD traits demonstrate strong convergent validity with relevant self‐reported Big Five traits (as identified by Lynam & Widiger, 2001). Directly observed behavior is meaningfully associated with acquaintances' judgments and self‐reports of PD‐relevant traits, and the associations between these judgments and behavior are strongest for traits associated with histrionic and schizoid PD. Vector correlations between behavioral profiles associated with informant and self‐reports show that both assessments have similar behavioral correlates. Associations between PD trait ratings and behavior appeared to differ as a function of gender, with males showing more and stronger correlations.

Conclusions

Informants' ratings of PD traits are impressively accurate, converging both with self‐reports of relevant traits and directly observed interpersonal behavior. Therefore, a comprehensive understanding of PDs and associated traits can be augmented by information from multiple acquaintances who have the opportunity to observe how an individual interacts with others on a daily basis across diverse contexts.
Consistency and stability of narrative coherence: An examination of personal narrative as a domain of adult personality
Authors: Waters Theodore E. A. , Köber Christin , Raby K. Lee , Habermas Tilmann , Fivush Robyn
Published: March 2018

Objective

Narrative theories of personality assume that individual differences in coherence reflect consistent and stable differences in narrative style rather than situational and event‐specific differences (e.g., McAdams & McLean, 2013). However, this assumption has received only modest empirical attention. Therefore, we present two studies testing the theoretical assumption of a consistent and stable coherent narrative style.

Method

Study 1 focused on the two most traumatic and most positive life events of 224 undergraduates. These event‐specific narratives were coded for three coherence dimensions: theme, context, and chronology (NaCCs; Reese et al., 2011). Study 2 focused on two life narratives told 4 years apart by 98 adults, which were coded for thematic, causal, and temporal coherence (Köber, Schmiedek, & Habermas, 2015).

Results

Confirmatory factor analysis in both studies revealed that individual differences in the coherence ratings were best explained by a model including both narrative style and event‐/narration‐specific latent variables.

Conclusions

The ways in which we tell autobiographical narratives reflect a stable feature of individual differences. Further, they suggest that this stable element of personality is necessary, but not sufficient, in accounting for specific event and life narrative coherence.
Gender Expression, Violence, and Bullying Victimization: Findings From Probability Samples of High School Students in 4 US School Districts
Authors: Gordon Allegra R. , Conron Kerith J. , Calzo Jerel P. , White Matthew T. , Reisner Sari L. , Austin S. Bryn
Published: March 2018

BACKGROUND

Young people may experience school‐based violence and bullying victimization related to their gender expression, independent of sexual orientation identity. However, the associations between gender expression and bullying and violence have not been examined in racially and ethnically diverse population‐based samples of high school students.

METHODS

This study includes 5469 students (13–18 years) from the 2013 Youth Risk Behavior Surveys conducted in 4 urban school districts. Respondents were 51% Hispanic/Latino, 21% black/African American, 14% white. Generalized additive models were used to examine the functional form of relationships between self‐reported gender expression (range: 1 = Most gender conforming, 7 = Most gender nonconforming) and 5 indicators of violence and bullying victimization. We estimated predicted probabilities across gender expression by sex, adjusting for sexual orientation identity and potential confounders.

RESULTS

Statistically significant quadratic associations indicated that girls and boys at the most gender conforming and nonconforming ends of the scale had elevated probabilities of fighting and fighting‐related injury, compared to those in the middle of the scale (p < .05). There was a significant linear relationship between gender expression and bullying victimization; every unit increase in gender nonconformity was associated with 15% greater odds of experiencing bullying (p < .0001).

CONCLUSIONS

School‐based victimization is associated with conformity and nonconformity to gender norms. School violence prevention programs should include gender diversity education.
Teacher Victimization in Authoritative School Environments
Authors: Kapa Ryan R. , Luke Jeremy , Moulthrop Dorothy , Gimbert Belinda
Published: March 2018

BACKGROUND

Victimization in schools is not limited to students. Teachers increasingly face threats and attacks from their students. An authoritative school environment, characterized by high structure and support, has been associated with lower rates of victimization. The purpose of this study was to explore the relationship between authoritative school environments and teacher victimization rates.

METHODS

Researchers examined public school teacher responses (N = 37,497) from the Schools and Staffing Survey regarding rules and issues facing the school community. Descriptive statistics were gathered, and a hierarchical regression technique was employed to assess the impact of a structured, supportive school environment on teacher victimization.

RESULTS

Results indicate an authoritative school environment helped reduce rates of teacher victimization. White, female teachers are among the teachers most likely to experience violence from students. Enforcing school rules, by both teachers and administrators, is the most effective way to diminish episodes of teacher victimization.

CONCLUSIONS

P‐12 school personnel should emphasize the importance of enforcing school rules and reducing negative issues, such as student truancy and apathy within each school. As high levels of structure and support reduce instances of violence, these findings have important implications for school environments and teacher health.
Parents' Executive Functioning and Involvement in Their Child's Education: An Integrated Literature Review
Authors: Wilson Damali M. , Gross Deborah
Published: March 2018

BACKGROUND

Parents' involvement in their children's education is integral to academic success. Several education‐based organizations have identified recommendations for how parents can best support their children's learning. However, executive functioning (EF), a high‐ordered cognitive skill set, contributes to the extent to which parents can follow through with these recommendations.

METHOD

This integrative review of the literature describes how executive function can affect parents' ability to facilitate and actively participate in their child's education and provides strategies for all school staff to strengthen parent‐school partnerships when parents have limitations in EF.

RESULTS

EF skills are fluid and influenced by several factors, including parental age, sleep, stress, and mood/affect. Despite possible limitations in parental EF, there are strategies school personnel can employ to strengthen partnership with parents to support their children's academic success.

CONCLUSIONS

As reforms in education call for increased customization and collaboration with families, parental EF is an important consideration for school personnel. Awareness and understanding of how parents' EF affects children's learning will help schools better support parents in supporting their children's academic success.