bluuebunny/crossref_metadata_2025_split huggingface dataset:
Field instrumentation for high‐resolution parallel monitoring of bedrock erosion and bedload transport
Authors: Beer Alexander R. , Turowski Jens M. , Fritschi Bruno , Rieke‐Zapp Dirk H. 
Published: September 2014

AbstractRiver incision is fundamental in shaping the Earth's surface. In mountainous regions with steep river beds, fluvial bedrock erosion by bedload transport is an important mechanism forming channels. However, there are only a few complete field datasets that can be used to improve process understanding and evaluate erosion models, especially at the process scale. To provide a simultaneous dataset of hydraulics, bedload transport and bedrock erosion at high temporal and spatial resolution, a new measuring device has been installed in the Erlenbach, a gauged stream in the Swiss Pre‐Alps. In this stream, bedload transport rates can be calculated from surveying deposits and from geophone plate sensors and bedload transport samples can be taken directly by an automated moving basket system. To measure bedrock erosion rates simultaneously, two natural stone slabs were mounted flush with the channel bed in a steel frame hosting various measurement devices. Force sensors below the slabs record normal stress and shear stress. At‐a‐point erosion rates on the slab surfaces are continuously measured at sub‐millimetre precision at three locations on each slab. In addition, the slab topography is monitored following erosive flood events. In this article (i) the ‘erosion scale’ device is described, (ii) data resolution and data quality is assessed by means of tests and event data, and (iii) the first transport event is discussed. The erosion scales are confirmed to provide data at high spatio‐temporal resolution for process analysis. The preliminary data show evidence for the tools effect in bedrock erosion. The bedrock slabs can be exchanged to obtain measurements for catchments with different lithologies for comparison. Copyright © 2014 John Wiley & Sons, Ltd.
Development of a groundwater fungal strain as a tool for toxicity assessment
Authors: Lategan Maria Josie , Hose Grant C. 
Published: September 2014

Abstract

Despite the significant ecological role played by fungi in groundwater, their value as indicators of groundwater pollution is not known, as fungi are notoriously challenging to assess for toxicity because of their varied morphological components, in particular their filamentous structures. Hence they are rarely used in environmental risk assessments and monitoring programs for aquatic systems. A rapid, low cost, 1-step static toxicity test targeting the hyphal components of fungi was developed that subsequently demonstrated the sensitivity of a ubiquitous and dominant groundwater fungal strain to metal contaminants. The strain demonstrates sensitivity to chromium &gt; copper &gt; zinc and relative resistance to arsenic. The introduction of a novel group of groundwater microorganisms—the fungi—for toxicity evaluation will strengthen current risk assessment programs for these ecosystems. Environ Toxicol Chem 2014;33:2826–2834. © 2014 SETAC
Living on the edge: Populations of two zooplankton species living closer to agricultural fields are more resistant to a common insecticide
Authors: Bendis Randall J. , Relyea Rick A. 
Published: September 2014

Abstract

Ecological communities across the globe are exposed to diverse natural and anthropogenic stressors and disturbances that can lead to community-wide impacts. Contaminants are a group of anthropogenic disturbances that are ubiquitous in the environment and can trigger trophic cascades, increased susceptibility to pathogens, reduced biodiversity, and altered ecosystems. In these ecosystems, substantial attention has been given to evolved resistance in targeted pest species, but little attention has been given to the evolution of resistance in nontarget species in nature. For the present study, the authors used laboratory toxicity tests to determine if 2 common, co-occurring species of freshwater zooplankton (Simocephalus vetulus and Daphnia pulex) showed population-level variation in sensitivity to a common insecticide (chlorpyrifos). For both species, it was found that populations living near agricultural fields—a proxy for pesticide use—were more resistant to chlorpyrifos than populations collected from ponds far from agriculture. This finding is consistent with the evolution of resistance to pesticides. To the authors' knowledge, only 1 previous study (using Daphnia magna) has demonstrated this relationship. Collectively, these results suggest that evolved resistance may be common in zooplankton populations located near agriculture. Moreover, because zooplankton play a key role in aquatic food webs, it is expected that population variation in resistance would dramatically alter aquatic food webs, particularly with exposure to low concentrations of insecticides. Environ Toxicol Chem 2014;33:2835–2841. © 2014 SETAC
Sorption of per- and polyfluoroalkyl substances (PFASs) on filter media: Implications for phase partitioning studies
Authors: Chandramouli Bharat , Benskin Jonathan P. , Hamilton M. Coreen , Cosgrove John R. 
Published: September 2014

Abstract

Per- and polyfluoroalkyl substances (PFASs), including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are ubiquitous in the environment. Investigations into their fate and potential phase-partitioning behavior require separating solid from aqueous phases via filtration. However, sorption of aqueous-phase PFASs on filtration media may lead to underestimation of PFAS concentrations in the aqueous phase. The authors investigated the sorption of perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids (PFPiAs), polyfluoroalkyl phosphate monoesters, polyfluoroalkyl phosphate diesters (diPAPs), fluorotelomer sulfonates, and perfluorooctane sulfonamide on filtration media. The effects of concentration (3 spiking levels), filter media (4 types), matrix (4 matrices), and compound structure on sorption are reported. Glass fiber filtration resulted in the least sorption, whereas polytetrafluoroethylene filters resulted in the most sorption (up to 98%). Analyte concentration had no significant effect. Sorption was generally consistent across matrix types except for samples affected by aqueous film forming foam deployment, which displayed high sorption of PFOS on nylon filters. Sorption usually increased with an increasing number of carbon or fluorine atoms and was most pronounced for PFPiAs and diPAPs (30–75% sorption). Overall, glass fiber filters are more recommended than nylon filters in environmental samples when phase separation is required. Use of filtration media for PFAS must be preceded by matrix-specific testing to account for unpredictable effects. Environ Toxicol Chem 2015;34:30–36. © 2014 SETAC
Forecasting Daily Variations of Stock Index Returns with a Multifractal Model of Realized Volatility
Authors: Lux Thomas , Morales‐Arias Leonardo , Sattarhoff Cristina 
Published: September 2014

ABSTRACTMultifractal models have recently been introduced as a new type of data‐generating process for asset returns and other financial data. Here we propose an adaptation of this model for realized volatility. We estimate this new model via generalized method of moments and perform forecasting by means of best linear forecasts derived via the Levinson–Durbin algorithm. Its out‐of‐sample performance is compared against other popular time series specifications. Using an intra‐day dataset for five major international stock market indices, we find that the the multifractal model for realized volatility improves upon forecasts of its earlier counterparts based on daily returns and of many other volatility models. While the more traditional RV‐ARFIMA model comes out as the most successful model (in terms of the number of cases in which it has the best forecasts for all combinations of forecast horizons and evaluation criteria), the new model performs often significantly better during the turbulent times of the recent financial crisis. Copyright © 2014 John Wiley & Sons, Ltd.
Gas Diffusion Layer Materials and their Effect on Polymer Electrolyte Fuel Cell Performance – Ex Situ and In Situ Characterization
Authors: El‐Kharouf A. , Rees N. V. , Steinberger‐Wilckens R. 
Published: September 2014

AbstractThe gas diffusion layer (GDL) has a vital role in the operation of a polymer electrolyte fuel cell (PEFC). Therefore, studying GDL characteristics and their effect on the cell performance is fundamental for the development of more efficient PEFCs.The work presented covers a selection of commercially available GDL types used in fuel cell development. It highlights some key GDL properties and their influence on PEFC performance. The results show that GDL materials have a direct effect on the ohmic and mass transport losses in the membrane electrode assembly (MEA). They also show that studying the effect of GDL properties on the performance is rather complex, due to the many interrelated properties.The study shows that GDL thickness has a significant effect on the mass transport properties of MEA, but has minimal effect on the ohmic losses. The bulk density of the substrate has a significant effect on the water transport properties and the maximum current density achieved. It is also found that woven and non‐woven GDLs achieve comparable performance at optimized operating conditions. Moreover, the felt fiber structure has higher ohmic resistance but achieves better performance than that of straight fiber carbon paper due to its enhanced water transport ability.
A Fuel‐Flexible Alkaline Direct Liquid Fuel Cell
Authors: Tran K. , Nguyen T. Q. , Bartrom A. M. , Sadiki A. , Haan J. L. 
Published: September 2014

AbstractWe constructed a fuel‐flexible fuel cell consisting of an alkaline anion exchange membrane, palladium anode, and platinum cathode. When an alcohol fuel was used with potassium hydroxide added to the fuel stream and oxygen was the oxidant, the following maximum power densities were achieved at 60 °C: ethanol (128 mW cm−2), 1‐propanol (101 mW cm−2), 2‐propanol (40 mW cm−2), ethylene glycol (117 mW cm−2), glycerol (78 mW cm−2), and propylene glycol (75 mW cm−2). We also observed a maximum power density of 302 mW cm−2 when potassium formate was used as the fuel under the same conditions. However, when potassium hydroxide was removed from the fuel stream, the maximum power density with ethanol decreased to 9 mW cm−2 (using oxygen as oxidant), while with formate it only decreased to 120 mW cm−2 (using air as the oxidant). Variations in the performance of each fuel are discussed. This fuel‐flexible fuel cell configuration is promising for a number of alcohol fuels. It is especially promising with potassium formate, since it does not require hydroxide added to the fuel stream for efficient operation.
Electronic Conductivity Enhancement of (La,Sr)TiO3 with Nb‐Doping on B‐Site
Authors: Kazakevičius E. , Tsekouras G. , Michalow‐Mauke K. A. , Kazlauskas S. , Graule T. 
Published: September 2014

AbstractB‐site doped, A‐site deficient strontium titanates with general formula LaxSr1–3x/2+γxNbyTi1–yO3–δ (x = 0.2, 0.25, 0.3, 0.35, 0.4; y = 0, 0.02, 0.03; γ = 0.03) were produced by flame spray synthesis and the electrical conductivity of dense ceramic bars sintered under reducing conditions measured over broad temperature and oxygen concentration ranges. As‐synthesized powders were nano‐scale and slightly reduced, while it was observed that sinterability was promoted by both La substitution and Nb doping. Electrical conductivity measurements on dense bars under reducing conditions revealed that stoichiometric substitution of Ti4+ by Nb5+ raised conductivity by ∼ 40%, with a maximum value of 226 S cm−1 observed at 900 °C. This was attributed to a higher concentration of $ {\rm{Ti}}_{{\rm{Ti}}}^{\prime} $ defects, due to concurrent and enhanced oxygen vacancy ($ {\rm{V}}_{\rm{o}}^{\bullet \bullet} $) formation under reducing conditions. The electronic properties of a slightly porous bar sample of the La0.3Sr0.559Nb0.02Ti0.98O3–δ composition were found to be stable over one redox cycle.
Quality of life in patients after resection of pT3 lateral tongue carcinoma: Microvascular reconstruction versus primary closure
Authors: Canis Martin , Weiss Bernhard G. , Ihler Friedrich , Hummers–Pradier Eva , Matthias Christoph , Wolff Hendrik A. 
Published: September 2014

ABSTRACTBackgroundControversy exists regarding the functional advantages of free flap reconstruction after partial glossectomy as compared to primary closure.MethodsForty patients were included in this retrospective analysis after resection of pT3 lateral tongue carcinomas. Twenty patients received a free forearm flap and 20 patients had a primary closure. All patients had adjuvant chemoradiation, were free of disease at least 1 year after therapy, and completed the German versions of the European Organization for Research and Treatment of Cancer (EORTC) questionnaires Quality of Life Questionnaire‐Core 30‐questions (QLQ‐C30) and Quality of Life Questionnaire‐Core 30 Head and Neck 35‐questions (QLQ‐H&N35).ResultsMean time between surgery and quality of life (QOL) assessment was 16.2 ± 3.4 months. The average resection was 41.60% (reconstruction) of the oral tongue, and 39.1% (primary closure). After reconstruction, patients had significantly (p > .05) fewer problems with the swallowing, speech, and social eating subdomains of the EORTC QLQ‐H&N35. All other items showed no significant differences.ConclusionOur preliminary results suggest that free flaps might be useful when treating pT3 tongue cancer. © 2015 Wiley Periodicals, Inc. Head Neck 38: 89–94, 2016
Pervaporation catalytic membrane reactor study for the production of ethyl acetate using Zr(SO4)2.4H2O coated chitosan membrane
Authors: Unlu Derya , Hilmioglu Nilufer Durmaz 
Published: September 2014

AbstractBACKGROUNDA pervaporation catalytic membrane reactor (PVCMR) can contain reaction and separation systems in one unit. This separation technique has attracted increasing attention in recent years due to its low energy requirement, environmentally friendly technology, easy control and scale‐up in integrated systems. The main aim of this present study is to develop a catalytic polymeric composite membrane for application in a PVCMR.RESULTSIn this study, esterification of acetic acid and ethanol were studied as a model reaction in a batch reactor and in a PVCMR. A composite membrane was prepared by coating chitosan membrane with a thin layer of Zr(SO4)2.4H2O. Tests were carried out to optimize operating conditions such as initial molar ratio, catalyst concentration and temperature. The acetic acid conversion was increased from 22% to 85% using a PVCMR by removal of water from the reaction mixture in the optimum operating conditions. Under the tested conditions, a molar ratio of reactants 1:1, catalyst concentration 0.25 g L‐1 and temperature 70 °C were found to be optimum conditions for separation.CONCLUSIONThe PVCMR exhibited higher performances than the batch reactor in the esterification of ethanol and acetic acid. The PVCMR can be used efficiently for other esterification reactions. © 2014 Society of Chemical Industry
Asymptomatic “placental prolapse” with cervical funneling in a patient with complete placenta previa
Authors: Adekola Henry , Lam‐Rachlin Jennifer , Bronshtein Elena , Abramowicz Jacques S. 
Published: September 2014

ABSTRACTWe describe the transvaginal sonographic findings in a patient with complete placenta previa and increased risk of preterm birth owing to a prior history of mid‐trimester pregnancy loss in whom we observed a short cervix and prolapse of the placenta and fetal membranes into the endocervical canal. We believe that this could lead to antepartum hemorrhage and mandate close observation when diagnosed. We introduced the term “placental prolapse” to describe our finding. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound, 43:122–125, 2015
Classification of Planning and Violent Behaviours in Serial Homicide: A Cross‐National Comparison Between South Africa and the US
Authors: Sorochinski Marina , Salfati C. Gabrielle , Labuschagne Gerard N. 
Published: September 2014

AbstractRecent literature suggests that different ‘styles’ of homicide will most appropriately be reflected in the different types of behaviours committed by offenders during the crime. In the last few years, there has been a move to standardise classification systems of single homicides and establish their cross‐national generalisability. Literature on serial homicide to date has mostly centred on homicides occurring in the US. However, national differences due to factors such as culture, national identity, political, and socio‐economic circumstances may decrease the applicability of these models or certain aspects thereof in other countries and thus must be evaluated. The present study tested the applicability in the South African context of a recently developed US‐based serial homicide crime scene classification framework. Specifically, this study compared the thematic differentiation in planning and violent behaviours that the offenders engage in and how this differentiation compares with that in the US. The sample consisted of 25 homicides that were in total responsible for the murder of 267 victims. Results indicated that overall, the framework is useful and applicable in the South African sample, but important environmental and contextual constraints must be taken into account. Copyright © 2014 John Wiley & Sons, Ltd.
The Effects of Modafinil on Convergent and Divergent Thinking of Creativity: A Randomized Controlled Trial
Authors: Mohamed Ahmed Dahir 
Published: September 2014

AbstractModafinil is a drug licensed for the treatment of narcolepsy and sleep apnea. Recently, modafinil has been reported to be used as a pharmacological cognitive enhancer by healthy individuals with no psychiatric disorders. This paper reports on a study that investigated the effects of modafinil on divergent and convergent thinking tasks of creativity. Sixty‐four healthy male (n = 31) and female (n = 33) volunteers participated in a randomized double‐blind placebo‐controlled parallel group design study. For the convergent thinking tasks, modafinil had no significant main effect on the Group Embedded Figures Task and the Remote Associates Task (RAT). However, a median split analysis showed that modafinil participants low in creativity personality trait had significantly higher RAT scores (Mean [M] = 6.85, SD = 3.39; 95% confidence interval [95% CI]: 5.53–8.2) than those high in creativity personality trait (M = 4.27, SD = 3.0; 95% CI: 2.4–6.0). For the divergent thinking tasks, relative to placebo (M = 1.195, SD = 0.28; 95% CI: 1.0–1.3), modafinil (M = 0.77, SD = 0.37; 95% CI: 0.63–0.92) significantly reduced the performance of flexibility scores and marginally reduced the elaboration scores as measured by the Abbreviated Torrance Test for Adults (ATTA). Overall, participants on modafinil (M = 6.3, SD = 2.6; 95% CI: 5.3–7.4) had significantly lower ATTA scores relative to participants on placebo (M = 9.5, SD = 2.3; 95% CI: 8.6–10.4). These results indicate that modafinil might reduce divergent thinking of creativity in healthy individuals. They suggest that, rather than being a more general cognitive enhancer, modafinil might have negative and subtle effects on creativity. However, the results are from a small‐scale trial, which tested a small number of participants. Therefore, the results need to be interpreted with caution. A replication with a large sample of participants is recommended.
Nut traits and nutritional composition of hazelnut (Corylus avellanaL.) as influenced by zinc fertilization
Authors: Özenç Nedim , Bender Özenç Damla 
Published: September 2014

AbstractBACKGROUNDZinc is an essential element for plants and its deficiency is a widespread problem throughout the world, causing decreased yields and nutritional quality. In this study the effect of zinc fertilization on some nut traits and the nutritional composition of ‘Tombul’ hazelnut (Corylus avellanaL.) variety cultivated in the Black Sea region of Turkey was investigated and the contribution of this nut to human nutrition determined. Trials were carried out at ‘Tombul’ hazelnut orchards, and zinc fertilizers were applied at 0, 0.2, 0.4, 0.8 and 1.6 kg Zn ha−1in three consecutive years.RESULTSSignificant differences in some nut traits and mineral composition (protein, total oil, ash, kernel percentage, empty and wrinkled nuts, copper, boron, manganese and molybdenum) were observed with zinc fertilizer applications. In terms of daily nutritional element requirements, 100 g of hazelnut provided about 44.74% phosphorus, 13.39% potassium, 19.32% calcium, 37.49% magnesium, 0.19% sodium, 51.63% iron, 25.73% zinc and 14.05% boron of the recommended daily amounts (RDAs), while copper, manganese and molybdenum contents exceeded theirRDAs.CONCLUSIONIn order to improve some nut traits and the mineral composition of hazelnut, 0.8 and 1.6 kg Zn ha−1fertilizations could be recommended in practice. © 2014 Society of Chemical Industry
Rapid End‐Group Modification of Polysaccharides for Biomaterial Applications in Regenerative Medicine
Authors: Bondalapati Somasekhar , Ruvinov Emil , Kryukov Olga , Cohen Smadar , Brik Ashraf 
Published: September 2014

Polysaccharides have emerged as important functional materials because of their unique properties such as biocompatibility, biodegradability, and availability of reactive sites for chemical modifications to optimize their properties. The overwhelming majority of the methods to modify polysaccharides employ random chemical modifications, which often improve certain properties while compromising others. On the other hand, the employed methods for selective modifications often require excess of coupling partners, long reaction times and are limited in their scope and wide applicability. To circumvent these drawbacks, aniline‐catalyzed oxime formation is developed for selective modification of a variety of polysaccharides through their reducing end. Notably, it is found that for efficient oxime formation, different conditions are required depending on the composition of the specific polysaccharide. It is also shown how our strategy can be applied to improve the physical and functional properties of alginate hydrogels, which are widely used in tissue engineering and regenerative medicine applications. While the randomly and selectively modified alginate exhibits similar viscoelastic properties, the latter forms significantly more stable hydrogel and superior cell adhesive and functional properties. Our results show that the developed conjugation reaction is robust and should open new opportunities for preparing polysaccharide‐based functional materials with unique properties.
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