bluuebunny/crossref_metadata_2025 huggingface dataset:
Submerged appurtenances and pipelines: An assessment of water levels and contaminant occurrence
Authors: Ebacher Gabrielle , Besner Marie‐Claude , Prévost Michèle
Published: October 2013

Submerged air vacuum valves and pipe leaks are potential entry points of contaminated water into drinking water distribution systems under low‐pressure conditions. Water levels in 20 valve vaults and 17 groundwater wells were monitored weekly for 8 months. The assembled data set indicated that water mains and air vacuum valves were commonly submerged in the investigated system. Urban runoff was found to be the dominant source of flooding in 11 of the 16 vaults containing water. A subset of 14 vaults and 10 piezometers were sampled for microbial and chemical parameters. Concentrations of chemical contaminants generally did not exceed drinking water standards. However, high counts of microbial fecal indicators were detected in numerous vaults. Runoff volumes of up to 255 L/mm of rainfall were found to enter a tested vault, and runoff water was identified as the main source of pesticides, personal care products, microbial fecal indicators, and hydrocarbons in vaults.
Risky behaviours among young people living with HIV attending care and treatment clinics in Dar Es Salaam, Tanzania: implications for prevention with a positive approach
Authors: Mhalu Aisa , Leyna Germana H , Mmbaga Elia J
Published: October 2013

Introduction

Prevention with a positive approach has been advocated as one of the main strategies to reduce new instances of HIV infection. Risky sexual behaviours among people living with HIV/AIDS are the cornerstone for this approach. Understanding the extent to which infected individuals practice risky behaviours is fundamental in designing appropriate population‐specific interventions. With the HIV infection transmission rates remaining high among young people in sub‐Saharan Africa, continued prevention among them remains a priority. This study therefore seeks to describe the magnitude and determinants of risky sexual behaviours among young people living with HIV.

Methods

A cross‐sectional study was conducted between June and July 2010 in selected Care and Treatment Clinics (CTCs) in Dar Es Salaam, Tanzania. A total of 282 HIV‐positive patients aged 15–24 were interviewed about their sexual behaviours using a questionnaire.

Results

Prevalence of unprotected sex was 40.0% among young males and 37.5% among young females (p<0.001). Multiple sexual partnerships were reported by 10.6% of males and 15.9% of females (p<0.005). More than 50% of the participants did not know about the HIV status of their sexual partners. A large proportion of participants had minimal knowledge of transmission (46.7% males vs. 60.4% females) and prevention (65.3% males vs. 73.4% females) of sexually transmitted infections (STIs). Independent predictors of condom use included non‐use of alcohol [adjusted odds ratio (AOR), 0.40 95% confidence interval (CI); 0.17–0.84] and younger age (15–19 years) (AOR, 2.76, 95% CI: 1.05–7.27). Being on antiretroviral therapy (AOR, 0.38, 95% CI: 0.17–0.85) and not knowing partners’ HIV sero‐status (AOR, 2.62, 95% CI: 1.14–5.10) predicted the practice of multiple sexual partnership.

Conclusions

Unprotected sex and multiple sexual partnerships were prevalent among young people living with HIV. Less knowledge on STI and lack of HIV disclosure increased the vulnerability and risk for HIV transmission among young people. Specific intervention measures addressing alcohol consumption, risky sexual behaviours, and STI transmission and prevention knowledge should be integrated in the routine HIV/AIDS care and treatment offered to this age group.
Graphitic Petal Electrodes for All‐Solid‐State Flexible Supercapacitors
Authors: Xiong Guoping , Meng Chuizhou , Reifenberger Ronald G. , Irazoqui Pedro P. , Fisher Timothy S.
Published: October 2013

The charge storage characteristics of a composite nanoarchitecture with a highly functional 3D morphology are reported. The electrodes are formed by the electropolymerization of aniline monomers into a nanometer‐thick polyaniline (PANI) film that conformally coats graphitic petals (GPs) grown by microwave plasma chemical vapor deposition (MPCVD) on conductive carbon cloth (CC). The hybrid CC/GPs/PANI electrodes yield results near the theoretical maximum capacitance for PANI of 2000 F g−1 (based on PANI mass) and a large area‐normalized specific capacitance of ≈2.6 F cm−2 (equivalent to a volumetric capacitance of ≈230 F cm−3) at a low current density of 1 A g−1 (based on PANI mass). The specific capacitances remain above 1200 F g−1 (based on PANI mass) for currents up to 100 A g−1 with correspondingly high area‐normalized values. The hybrid electrodes also exhibit a high rate capability with an energy density of 110 Wh kg−1 and a maximum power density of 265 kW kg−1 at a current density of 100 A g−1. Long‐term cyclic stability is good (≈7% loss of initial capacitance after 2000 cycles), with coulombic efficiencies >99%. Moreover, prototype all‐solid‐state flexible supercapacitors fabricated from these hybrid electrodes exhibit excellent energy storage performance.
Graphene‐Based Materials for Solar Cell Applications
Authors: Yin Zongyou , Zhu Jixin , He Qiyuan , Cao Xiehong , Tan Chaoliang , Chen Hongyu , Yan Qingyu , Zhang Hua
Published: October 2013

Graphene has attracted increasing attention due to its unique electrical, optical, optoelectronic, and mechanical properties, which have opened up huge numbers of opportunities for applications. An overview of the recent research on graphene and its derivatives is presented, with a particular focus on synthesis, properties, and applications in solar cells.
Transfer of a nanoparticle product between different mixers using latent variable model inversion
Authors: Tomba Emanuele , Meneghetti Natascia , Facco Pierantonio , Zelenková Tereza , Barresi Antonello A. , Marchisio Daniele L. , Bezzo Fabrizio , Barolo Massimiliano
Published: October 2013

An experimental nanoparticle preparation process by solvent displacement in passive mixers is considered. The problem under investigation is to estimate the operating conditions in a target device (Mixer B) in order to obtain a product of assigned properties that has already been manufactured in a source device of different geometry (Mixer A). A large historical database is available for Mixer A, whereas a limited historical database is available for Mixer B. The difference in device geometries causes a different mixing performance within the devices, which is very difficult to capture using mechanistic models. The problem is further complicated by the fact that Mixer B can only be run under an experimental setup that is different from the one under which the available historical dataset was obtained. A joint‐Y projection to latent structures (JY‐PLS) model inversion approach is used to transfer the nanoparticle product from Mixer A to Mixer B. The Mixer B operating conditions estimated by the model are tested experimentally and confirm the model predictions within the experimental uncertainty. Since the inversion of the JY‐PLS model generates an infinite number of solutions that all lie in the so‐called null space, experiments are carried out to provide (to the authors' knowledge) the first experimental validation of the theoretical concept of null space. Finally, by interpreting the JY‐PLS model parameters from first principles, the understanding of the system physics is improved. © 2013 American Institute of Chemical Engineers AIChE J, 60: 123–135, 2014
Roles of age, length of service and job in work‐related injury: A prospective study of 63,620 person‐years in female workers
Authors: Chau Nearkasen , Dehaene Dominique , Benamghar Lahoucine , Bourgkard Eve , Mur Jean‐Marie , Touron Christian , Wild Pascal
Published: October 2013

Background

The roles of age, length of service and job in various work‐related injury types are unknown and deserve investigations among female workers. This study assessed their roles in the occurrence of injury.

Methods

Three‐year prospective study of all 22,952 permanently employed women at the French national railway company: 63,620 person‐years, 756 injuries with working days lost, coded using the company's injury classification derived from that of the French health insurance scheme. We investigated the incidence of four types of injury: fall on same level, fall to lower level, materials/equipment/objects handling, and other injuries. Data were analyzed using negative binomial regression.

Results

Workers aged <25 were subject to a higher risk for all types of injuries. Older workers (45–55 years) were subject to a higher injury risk for fall on same level and fall to lower level. For fall on same level as for fall to lower level the relative risk decreased steadily with increasing length of service with the company, from 1.60 for 1 year to 0.50–0.60 for ≥30 years. For injuries due to materials/equipment/objects handling the relative risk decreased from 1.05 for one year to 0.49 for 5–9 years, and then increased to about 1.50 for 20–29 years and ≥30 years.

Conclusions

Younger and shorter lengths of service were at risk for various types of injuries. Higher length of service was at risk for injury due to materials/equipment/objects handling. Preventive measures should consider the respective risks associated with age, years of employment and job. Am. J. Ind. Med. 57:172–183, 2014. © 2013 Wiley Periodicals, Inc.
The impact of asbestos exposure in Swedish construction workers
Authors: Järvholm Bengt , Englund Anders
Published: October 2013

Objective

To study the occurrence of pleural mesothelioma as a measure of the impact on health from asbestos exposure in the construction industry.

Methods

The occurrence of pleural mesothelioma in different occupations, time periods and birth cohorts was studied in a cohort of construction workers. They were prospectively followed after they had participated in health examinations between 1971 and 1993. The analysis was restricted to men and in total 367,568 men was included in the analysis.

Results

In total there were 419 cases of pleural mesotheliomas between 1972 and 2009. As expected the age adjusted incidence was high in insulation workers and plumbers (39 and 16 cases per 100,000 person‐years, respectively). However, only 21% of the pleural mesotheliomas occurred in those occupational groups. Occupational groups with many cases of pleural mesothelioma were concrete workers (N = 56), wood workers (N = 55), painters (N = 32), electricians (N = 48), and foremen (N = 37). The highest risk was in birth cohorts born between 1935 and 1945. Between 1995 and 2009 around one‐third of all male cases in the country occurred in this birth cohort. The risk seemed to decrease considerably in men born after 1955.

Conclusion

In Sweden a considerable proportion of pleural mesotheliomas occur among construction workers; and not only in jobs traditionally associated with asbestos exposure such as insulators and plumbers but also among electricians, for example. The results shows that asbestos exposure occurs in many occupational groups, indicating that safe handling of asbestos is a very difficult or even impossible task in the construction industry. Am. J. Ind. Med. 57:49–55, 2014. © 2013 Wiley Periodicals, Inc.
Genome‐wide copy number scan identifies disruption of PCDH11X in developmental dyslexia
Authors: Veerappa Avinash M. , Saldanha Marita , Padakannaya Prakash , Ramachandra Nallur B.
Published: October 2013

Developmental dyslexia (DD) is a complex heritable disorder with unexpected difficulty in learning to read and spell despite adequate intelligence, education, environment, and normal senses. We performed a whole genome copy number variations (CNV) scan on 11 dyslexic families consisting of 14 dyslexic subjects and 24 non dyslexic members using 1.8 million combined SNP and CNV markers. We found CNVs affecting protocadherin genes in six dyslexics from three families, while none among the non‐dyslexic control members showed any CNV in protocadherins. We identified duplications in five cases and a deletion in one case in Xq21.3 region bearing PCDH11X. Unequal recombination between the X‐transposed region (XTR) of Yp11.2 and the X chromosome might be causing these structural changes. PCDH11X, expressed in brain is implicated in cell–cell communication, verbal ability, cerebral asymmetry, and dendritic synaptic plasticity, may be regarded as a new candidate gene for dyslexia. © 2013 Wiley Periodicals, Inc.
Simulating quantum magnets with symmetric top molecules
Authors: Wall Michael L. , Maeda Kenji , Carr Lincoln D.
Published: October 2013

A correspondence is established between the electric dipole matrix elements of a polyatomic symmetric top molecule in a state with nonzero projection of the total angular momentum on the symmetry axis of the molecule and the magnetic dipole matrix elements of a magnetic dipole associated with an elemental spin F. It is shown that this correspondence makes it possible to perform quantum simulation of the single‐particle spectrum and the dipole‐dipole interactions of magnetic dipoles in a static external magnetic field with symmetric top molecules subject to a static external electric field . It is further shown that no such correspondence exists for 1Σ molecules in static fields, such as the alkali metal dimers. The effective spin angular momentum of the simulated magnetic dipole corresponds to the rotational angular momentum of the symmetric top molecule, and so quantum simulation of arbitrarily large integer spins is possible. Further, taking the molecule CH3F as an example, it is shown that the characteristic dipole‐dipole interaction energies of the simulated magnetic dipole are a factor of 620, 600, and 310 larger than for the highly magnetic atoms Chromium, Erbium, and Dysprosium, respectively. Several applications of the correspondence for many‐body physics are presented, including long‐range and anisotropic spin models with arbitrary integer spin S using symmetric top molecules in optical lattices, quantum simulation of molecular magnets, and spontaneous demagnetization of Bose‐Einstein condensates due to dipole‐dipole interactions. These results are expected to be relevant as cold symmetric top molecules reach quantum degeneracy through Stark deceleration and opto‐electrical cooling.
A rapid and efficient catalysis system for the synthesis of 4‐vinylbiphenyl derivatives
Authors: Ma Xiaowei , Liu Yan , Liu Ping , Xie Jianwei , Dai Bin , Liu Zhiyong
Published: October 2013

A series of 4‐vinylbiphenyl derivatives were synthesized by Pd(OAc)2/PCy3‐catalyzed Suzuki–Miyaura reaction in the presence of K3PO4.3H2O as base in toluene at 80°C for only 10–30 min, and the corresponding products achieved 65–98% yields. According to this efficient C―C bond‐forming method, the obtained yields of 4‐vinylbiphenyl liquid crystal compounds were up to 92–96%. Copyright © 2013 John Wiley & Sons, Ltd.
Model‐directed engineering of “difficult‐to‐express” monoclonal antibody production by Chinese hamster ovary cells
Authors: Pybus Leon P. , Dean Greg , West Nathan R. , Smith Andrew , Daramola Olalekan , Field Ray , Wilkinson Stephen J. , James David C.
Published: October 2013

Despite improvements in volumetric titer for monoclonal antibody (MAb) production processes using Chinese hamster ovary (CHO) cells, some “difficult‐to‐express” (DTE) MAbs inexplicably reach much lower process titers. These DTE MAbs require intensive cell line and process development activity, rendering them more costly or even unsuitable to manufacture. To rapidly and rationally identify an optimal strategy to improve production of DTE MAbs, we have developed an engineering design platform combining high‐yielding transient production, empirical modeling of MAb synthesis incorporating an unfolded protein response (UPR) regulatory loop with directed expression and cell engineering approaches. Utilizing a panel of eight IgG1λ MAbs varying >4‐fold in volumetric titer, we showed that MAb‐specific limitations on folding and assembly rate functioned to induce a proportionate UPR in host CHO cells with a corresponding reduction in cell growth rate. Derived from comparative empirical modeling of cellular constraints on the production of each MAb we employed two strategies to increase production of DTE MAbs designed to avoid UPR induction through an improvement in the rate/cellular capacity for MAb folding and assembly reactions. Firstly, we altered the transfected LC:HC gene ratio and secondly, we co‐expressed a variety of molecular chaperones, foldases or UPR transactivators (BiP, CypB, PDI, and active forms of ATF6 and XBP1) with recombinant MAbs. DTE MAb production was significantly improved by both strategies, although the mode of action was dependent upon the approach employed. Increased LC:HC ratio or CypB co‐expression improved cell growth with no effect on qP. In contrast, BiP, ATF6c and XBP1s co‐expression increased qP and reduced cell growth. This study demonstrates that expression‐engineering strategies to improve production of DTE proteins in mammalian cells should be product specific, and based on rapid predictive tools to assess the relative impact of different engineering interventions. Biotechnol. Bioeng. 2014;111: 372–385. © 2013 Wiley Periodicals, Inc.
Enhancing Corporate Environmental Performance Through Reporting and Roadmaps
Authors: Caritte Victor , Acha Salvador , Shah Nilay
Published: October 2013

Managing the carbon footprint of companies and addressing their respective decarbonization plans is a challenging endeavour. The aim of this study is to help companies better understand the issues around decarbonization and environmental performance by suggesting a holistic management process on which they could embark. This process comprises two crucial steps, which are (a) sustainability reporting and (b) low‐carbon roadmaps. These steps are covered and further developed based on a detailed study of the UK food retail sector. This sector is relevant due to its economic and environmental importance, but most importantly it has a significant record of available environmental reports in the public domain and a large potential to influence consumers, policy makers and multiple supply chains.

Sustainability reporting is assessed by analysing environmental KPIs disclosed in corporate social responsibility (CSR) reports, and then these are compared against industry standards. This analysis highlights a general lack of consistency and transparency in CSR reporting of UK food retailers. Consequently, a low‐carbon roadmap based on relevant KPIs and on the ‘backcasting’ framework is presented as a case study in order to showcase how a hypothetical UK food retailer can employ a low‐carbon roadmap. The case study demonstrates that ambitious environmental targets are achievable if robust corporate action plans are followed. Furthermore, the case study indicates that capital might be misallocated in favour of highly visible environmental stores and on‐site energy generation technologies, whilst more could be done by applying energy efficiency measures that have the potential to deliver substantial carbon savings. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment.
Contrasting effects of Krüppel‐like factor 4 on X‐ray‐induced double‐strand and single‐strand DNA breaks in mouse astrocytes
Authors: Zhang Ji , Cui Fengmei , Li Lei , Yang Jiangtao , Zhang Liyuan , Chen Qiu , Tian Ye
Published: October 2013

Astrocytes, the most common cell type in the brain, play a principal role in the repair of damaged brain tissues during external radiotherapy of brain tumours. As a downstream gene of p53, the effects of Krüppel‐like factor 4 (KLF4) in response to X‐ray‐induced DNA damage in astrocytes are unclear. In the present study, KLF4 expression was upregulated after the exposure of astrocytes isolated from the murine brain. Inhibition of KLF4 expression using lentiviral transduction produced less double‐strand DNA breaks (DSB) determined by a neutral comet assay and flow cytometric analysis of phosphorylated histone family 2A variant and more single‐strand DNA breaks (SSB) determined by a basic comet assay when the astrocytes were exposed to 4 Gy of X‐ray radiation. These data suggest that radiation exposure of the tissues around brain tumour during radiation therapy causes KLF4 overexpression in astrocytes, which induces more DSB and reduces SSB. This causes the adverse effects of radiation therapy in the treatment of brain tumours. Copyright © 2013 John Wiley & Sons, Ltd.
Bone formation in adipose‐derived stem cells isolated from elderly patients with osteoporosis: a preliminary study
Authors: Jiang Ming , Wang Xin , Liu Hongzhi , Zhou Lugang , Jiang Tingshu , Zhou Huihui , Hao Wei
Published: October 2013

We have explored the osteogenic potency of adipose‐derived stem cells from osteoporotic patients (opASCs). opASCs were osteogenically induced in vitro with collagen I hydrogel or in culture plate. Detection of alkaline phosphatase (ALPase) and cell mineralisation, and quantitative RT‐PCR of collagen I, osteocalcin and bone sialoprotein were undertaken. Proliferation and morphology studies were also performed. After 14 days, opASCs‐collagen I hydrogel composite was implanted into nude mice for 4 weeks prior to radiographic and histological analysis. Staining of ALPase and cell mineralisation was strongly positive in opASCs. Fibroblast‐like opASCs induced with collagen I hydrogel were evenly distributed and proliferated at a higher rate than in culture plates, showing similar growth curves for both genders. Expression of ALPase activity, cell mineralisation and osteogenic specific genes were higher in opASCs with collagen I hydrogel (male samples had better osteogenicity than female samples) than in culture plates. After implantation for 4 weeks, radiopaque area signifying new bone tissue was observed in opASCs‐collagen I hydrogel composite, with no donor gender differences. Thus opASCs with collagen I hydrogel have adequate osteogenic potency and offer new possibilities for osteoporosis‐related bone tissue engineering in male and female patients.
Effect of moxidectin on CYP3A4 activity as evaluated by oral midazolam pharmacokinetics in healthy subjects
Authors: Korth‐Bradley Joan M. , Parks Virginia , Wagner Frank , Chalon Stephan , Gourley Ian , Matschke Kyle , Gossart Sophie , Ripp Sharon L. , Fleckenstein Lawrence
Published: October 2013

In order to evaluate the potential for CYP3A4 induction by moxidectin, midazolam pharmacokinetic (PK) parameters were compared before and after moxidectin administration. Healthy subjects received a single 8 mg dose of moxidectin and 3 single 7.5 mg doses of midazolam 3 days before, and 7 and 89 days after the moxidectin. Blood samples were taken for 24 hours to measure midazolam and metabolites in plasma, and for 89 days to measure moxidectin in plasma after dose administration. Noncompartmental PK analyses were performed for each analyte. Analysis of variance was performed on log‐transformed midazolam parameters with treatment day as a fixed effect. Adverse events were recorded and laboratory tests, physical examinations, pulse oximetry monitoring, vital sign measurement, and electrocardiograms performed. Thirty‐nine subjects were enrolled in the study; PK data were available for 37 subjects. Moxidectin PK parameters were similar to previous studies. There were no significant changes in PK for midazolam or its metabolites 7 or 89 days after moxidectin administration. Adverse events were generally mild and there were no relevant changes in safety assessments. Thus, 8 mg moxidectin does not induce CYP3A4 activity and other CYP3A4 substrates are unlikely to be affected by moxidectin co‐administration.
Sustainability Management and Small and Medium‐Sized Enterprises: Managers' Awareness and Implementation of Innovative Tools
Authors: Johnson Matthew P.
Published: October 2013

With the intention of integrating environmental and social practices in small and medium‐sized enterprises (SMEs), a growing body of research proposes the implementation of corporate social responsibility (CSR) and environmental management tools. Collectively referred to as sustainability management tools in this paper, voluntary management approaches range from environmental and social audits, indicators, and management systems, to reporting schemes and stakeholder dialogues. While the adoption of such management tools in SMEs has been increasingly anticipated in the academic literature, the rates of awareness and implementation for these management tools are missing. Furthermore, the connections between awareness and implementation remain under‐researched. Using a framework for innovation diffusion, the results from a web‐based survey with 176 German SME managers investigate these connections. Rogers' model is particularly useful to identify managerial and organizational characteristics that might explain why particular SMEs are more likely to adopt sustainability management tools. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment
Inferring parturition and neonate survival from movement patterns of female ungulates: a case study using woodland caribou
Authors: DeMars Craig A. , Auger‐Méthé Marie , Schlägel Ulrike E. , Boutin Stan
Published: October 2013

Analyses of animal movement data have primarily focused on understanding patterns of space use and the behavioural processes driving them. Here, we analyzed animal movement data to infer components of individual fitness, specifically parturition and neonate survival. We predicted that parturition and neonate loss events could be identified by sudden and marked changes in female movement patterns. Using GPS radio‐telemetry data from female woodland caribou (Rangifer tarandus caribou), we developed and tested two novel movement‐based methods for inferring parturition and neonate survival. The first method estimated movement thresholds indicative of parturition and neonate loss from population‐level data then applied these thresholds in a moving‐window analysis on individual time‐series data. The second method used an individual‐based approach that discriminated among three a priori models representing the movement patterns of non‐parturient females, females with surviving offspring, and females losing offspring. The models assumed that step lengths (the distance between successive GPS locations) were exponentially distributed and that abrupt changes in the scale parameter of the exponential distribution were indicative of parturition and offspring loss. Both methods predicted parturition with near certainty (>97% accuracy) and produced appropriate predictions of parturition dates. Prediction of neonate survival was affected by data quality for both methods; however, when using high quality data (i.e., with few missing GPS locations), the individual‐based method performed better, predicting neonate survival status with an accuracy rate of 87%. Understanding ungulate population dynamics often requires estimates of parturition and neonate survival rates. With GPS radio‐collars increasingly being used in research and management of ungulates, our movement‐based methods represent a viable approach for estimating rates of both parameters.
Oxytocin and Anorexia Nervosa: A Review of the Emerging Literature
Authors: Maguire Sarah , O'Dell Adrienne , Touyz Lauren , Russell Janice
Published: October 2013

Anorexia nervosa (AN) is an intractable illness that is difficult to treat. The identification of neural correlates and novel agents to transform treatment has become priority avenues for research. Oxytocin (OT) is a neuropeptide whose emerging sphere of influence on mammalian behaviour and demonstrated impact on psychiatric illness suggest it may have potential in AN. In this paper, we undertake a targeted summary of the existing literature on OT research as it pertains to brain based behaviour and psychiatric dysfunction. Then, we conduct a systematic review of OT in AN. Papers that addressed any aspect of the OT system in AN were examined. The existing literature, although limited and based on small sample sizes, suggests a derangement of the OT system in AN that may normalise upon recovery. Preliminary pilot data from unpublished studies suggest a potential effect of OT administration on eating‐related indices. Copyright © 2013 John Wiley & Sons, Ltd and Eating Disorders Association.
Effects of silver nanoparticles on soil enzyme activities with and without added organic matter
Authors: Peyrot Caroline , Wilkinson Kevin J. , Desrosiers Mélanie , Sauvé Sébastien
Published: October 2013

The effects of silver nanoparticles (AgNPs) on terrestrial ecosystems need to be better understood and assessed. Cationic silver (Ag+) has well-documented toxicity against bacteria, but it is not clear what will be the effect of nanoscale Ag. In the present study, the potential effects of AgNPs were investigated in soils by measuring activity of the enzymes phosphomonoesterase, arylsulfatase, β-D-glucosidase, and leucine-aminopeptidase. The toxicity of AgNPs was compared with that of ionic Ag, and the ameliorating effects of soil organic matter were evaluated. To this end, 2 soils with different organic matter contents were artificially contaminated with either AgNPs or Ag-acetate at equivalent total Ag concentrations. In general, enzyme activities were inhibited as a function of the Ag concentration in the soil. In the AgNP exposures, only a small fraction of the AgNP was actually truly dissolved (found in the <1-nm fraction), suggesting that the particulate forms of AgNPs resulted in a significant inhibition of soil enzymes. The addition of organic matter to the soils appeared to enhance enzyme activities; however, the mechanism of organic matter action is not clear given that dissolved Ag concentrations were similar in both the organic-matter–amended and unamended soils. The present study shows that the AgNP produces significant negative effects on the soil enzyme activities tested. The Ag chemical speciation measurements suggested that the AgNP caused greater toxic effects to the soil enzymes at the low Ag concentrations. For the larger concentrations of total soil Ag, causes of the negative effects on enzyme activities are less obvious but suggest that colloidal forms of Ag play a role. Environ Toxicol Chem 2014;33:115–125. © 2013 SETAC
Considerations for test design to accommodate energy-budget models in ecotoxicology: A case study for acetone in the pond snail Lymnaea stagnalis
Authors: Barsi Alpar , Jager Tjalling , Collinet Marc , Lagadic Laurent , Ducrot Virginie
Published: October 2013

Toxicokinetic–toxicodynamic (TKTD) modeling offers many advantages in the analysis of ecotoxicity test data. Calibration of TKTD models, however, places different demands on test design compared with classical concentration–response approaches. In the present study, useful complementary information is provided regarding test design for TKTD modeling. A case study is presented for the pond snail Lymnaea stagnalis exposed to the narcotic compound acetone, in which the data on all endpoints were analyzed together using a relatively simple TKTD model called DEBkiss. Furthermore, the influence of the data used for calibration on accuracy and precision of model parameters is discussed. The DEBkiss model described toxic effects on survival, growth, and reproduction over time well, within a single integrated analysis. Regarding the parameter estimates (e.g., no-effect concentration), precision rather than accuracy was affected depending on which data set was used for model calibration. In addition, the present study shows that the intrinsic sensitivity of snails to acetone stays the same across different life stages, including the embryonic stage. In fact, the data on egg development allowed for selection of a unique metabolic mode of action for the toxicant. Practical and theoretical considerations for test design to accommodate TKTD modeling are discussed in the hope that this information will aid other researchers to make the best possible use of their test animals. Environ Toxicol Chem 2014;33:1466–1475. © 2014 SETAC
Modeling dynamic triggering of tectonic tremor using a brittle‐ductile friction model
Authors: Trugman Daniel T. , Daub Eric G. , Guyer Robert A. , Johnson Paul A.
Published: October 2013

We study the physics of dynamically triggered tectonic tremor by applying a brittle‐ductile friction model in which we conceptualize the tremor source as a rigid block subject to driving and frictional forces. To simulate dynamic triggering of tremor, we apply a stress perturbation that mimics the surface waves of remote earthquakes. The tectonic and wave perturbation stresses define a phase space that demonstrates that both the timing and amplitude of the dynamic perturbations control the fundamental characteristics of triggered tremor. Tremor can be triggered instantaneously or with a delayed onset if the dynamic perturbation significantly alters the frictional state of the tremor source.
Dissolved and particulate organic carbon fluxes from an agricultural watershed during consecutive tropical storms
Authors: Caverly Emma , Kaste James M. , Hancock Gregory S. , Chambers Randolph M.
Published: October 2013

Low‐frequency high‐magnitude hydrologic events mobilize a disproportionate amount of dissolved organic carbon (DOC) from watersheds, but few studies measure the role of extreme storms in exporting organic carbon from croplands. We use high‐resolution measurements of storm runoff to quantify DOC and particulate organic carbon (POC) fluxes from an agricultural field during consecutive tropical storms that delivered 41 cm of rainfall to the Virginia Coastal Plain. Over a 2 week period, we measured exports of 22 kg DOC ha−1 and 11.3 kg POC ha−1. Ultraviolet absorbance measurements indicate that the aromatic DOC fraction systematically increased as plant‐derived aliphatic carbon was depleted during the initial event. Croplands can have event‐scale carbon losses that equal or exceed published estimates of annual export for perennial streams draining forested and mixed land use watersheds. We quantify aromatic DOC fractions approaching 50%, indicating that agricultural stormflow can produce a significant load of relatively photoreactive carbon.
Fibrosis progression in human immunodeficiency virus/hepatitis C virus coinfected adults: Prospective analysis of 435 liver biopsy pairs
Authors: Konerman Monica A. , Mehta Shruti H. , Sutcliffe Catherine G. , Vu Trang , Higgins Yvonne , Torbenson Michael S. , Moore Richard D. , Thomas David L. , Sulkowski Mark S.
Published: October 2013

Human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfection is associated with progressive liver disease. However, the rate of progression is variable and the ability to differentiate patients with stable versus progressive HCV disease is limited. The objective of this study was to assess the incidence of and risk factors for fibrosis progression in a prospective cohort of coinfected patients. Overall, 435 liver biopsy pairs from 282 patients without cirrhosis were analyzed. Biopsies were scored according to the METAVIR system by a single pathologist blind to biopsy sequence. Fibrosis progression was defined as an increase of at least one METAVIR fibrosis stage between paired biopsies. The majority of patients were African American (84.8%), male (67.7%), and infected with HCV genotype 1 (93.4%). On initial biopsy, no or minimal fibrosis was identified in 243 patients (86%). The median interval between biopsies was 2.5 years. Fibrosis progression was observed in 97 of 282 (34%) patients and 149 of 435 (34%) biopsy pairs. After adjustment, greater body mass index (adjusted odds ratio [aOR]: 1.04 per 1 unit increase), diabetes (aOR: 1.56), and hepatic steatosis (aOR: 1.78) at the time of initial biopsy were marginally associated with subsequent fibrosis progression. Between biopsies, elevated serum aspartate and alanine aminotransferase (AST, ALT) (aOR AST: 3.34, ALT: 2.18 for >25% values >100 U/L versus <25% values >100 U/L) were strongly associated with fibrosis progression. Conclusion: Fibrosis progression is common among HIV/HCV coinfected patients; these data suggest that progression can be rapid. Persistent elevations in serum transaminase levels may serve as important noninvasive markers to identify subsets of patients who are more likely to progress and thus warrant closer monitoring and consideration of HCV treatment. (HEPATOLOGY 2014;59:767–775)
Equations for converting scores between depression scales (MÅDRS, SRS, PHQ‐9 and BDI‐II): good statistical, but weak idiographic, validity
Authors: Hawley Chris J. , Gale Tim M. , Smith Paul St John , Jain Sanjay , Farag Ako , Kondan Raj , Avent Cerian , Graham Juliet
Published: October 2013

Background

A variety of depression rating scales are currently used in clinical and research practice. As these scales are generally thought to correlate well, there may be some benefit in deriving equations to translate the score on one scale to that on another.

Method

Using pairwise ratings, we compared the Montgomery‐Åsberg Depression Rating Scale (MÅDRS), Beck Depression Inventory II (BDI‐II), Patient Health Questionnaire (PHQ‐9) and Zung Self Rated Scale (SRS). The primary comparisons of interest were as follows: PHQ‐9 and MÅDRS, PHQ‐9 and BDI‐II, SRS and MÅDRS, and SRS and PHQ‐9. One hundred and fifty pairs of ratings were collected for each of these four comparisons, and these were used in a regression analysis to generate a predictive equation between scale pairs. The predictive equations were then tested for accuracy by using novel data.

Results

There was a reasonably strong correlation between scales. Simple regression equations describe the relationships between certain permutations of the BDI‐II, PHQ‐9, SRS and MÅDRS well enough to allow the score on one scale to be estimated from the score on another. On average, the equations work well. However, when used to predict individual cases, they often fail.

Conclusion

It does appear that conversion equations for depression scores are precise enough to be of use when applied to averages; these might aid comparison of data across different studies, meta‐analysis or instrument selection for clinical trials. But regarding scale translation at the idiographic level, the variability we have observed is so great that severe doubt is cast on the validity of such an approach. Copyright © 2013 John Wiley & Sons, Ltd.
Acceleration of dermal wound healing by using electrospun curcumin‐loaded poly(ε‐caprolactone)‐poly(ethylene glycol)‐poly(ε‐caprolactone) fibrous mats
Authors: Fu Shao‐Zhi , Meng Xiao‐Hang , Fan Juan , Yang Ling‐Lin , Wen Qing‐Lian , Ye Su‐Juan , Lin Sheng , Wang Bi‐Qiong , Chen Lan‐Lan , Wu Jing‐Bo , Chen Yue , Fan Jun‐Ming , Li Zhi
Published: October 2013

This study prepared a composite scaffold composed of curcumin and poly(ε‐caprolactone)‐poly(ethylene glycol)‐poly(ε‐caprolactone) (PCL‐PEG‐PCL, PCEC) copolymer using coelectrospinning technology. Incorporation of curcumin into the polymeric matrix had an obvious effect on the morphology and dimension of PCEC/curcumin fibers. The results of in vitro anti‐oxidant tests and of the cytotoxicity assay demonstrated that the curcumin‐loaded PCEC fibrous mats had significant anti‐oxidant efficacy and low cytotoxicity. Curcumin could be sustainably released from the fibrous scaffolds. More importantly, in vivo efficacy in enhancing wound repair was also investigated based on a full‐thickness dermal defect model for Wistar rats. The results indicated that the PCEC/curcumin fibrous mats had a significant advantage in promoting wound healing. At 21 days post‐operation, the dermal defect was basically recovered to its normal condition. A percentage of wound closure reached up to 93.3 ± 5.6% compared with 76.9 ± 4.9% of the untreated control (p < 0.05). Therefore, the as‐prepared PCEC/curcumin composite mats are a promising candidate for use as wound dressing. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 533–542, 2014.
The development of an automated and GMP compliant FASTlab™ Synthesis of [18F]GE‐180; a radiotracer for imaging translocator protein (TSPO)
Authors: Wickstrøm Torild , Clarke Alan , Gausemel Ingvil , Horn Eric , Jørgensen Karina , Khan Imtiaz , Mantzilas Dimitrios , Rajanayagam Thanushan , In 't Veld Dirk‐Jan , Trigg William
Published: October 2013

The level of the translocator protein (TSPO) increases dramatically in microglial cells when the cells are activated in response to neuronal injury and insult. The radiotracer [18F]GE‐180 binds selectively and with high affinity to TSPO and can therefore be used to measure neuroinflammation in a variety of disease states.

An optimized, automated synthesis of [18F]GE‐180 has been developed for the GE FASTlab™ synthesizer. The entire process takes place on the single‐use cassette. The radiolabelling is performed by nucleophilic fluorination of the S‐ enantiomer mesylate precursor. The crude product is purified post‐radiolabelling using two solid‐phase extraction cartridges integrated on the cassette. Experimental design and multivariate data analysis were used to assess the robustness, and critical steps were optimized with respect to efficacy and quality.

The average radiochemical yield is 48% (RSD 6%, non‐decay corrected), and the synthesis time including purification is approximately 43 min. The radiochemical purity is ≥95% for radioactive concentration ≤1100 MBq/mL. The total amount of precursor‐related chemical impurities is 1–2 µg/mL.

The use of solid‐phase extraction purification results in a robust GMP compliant process with a product of high chemical and radiochemical purity and consistent performance across positron emission tomography (PET) centers.
Bacterial succession and degradative changes by biofilm on plastic medium for wastewater treatment
Authors: Khatoon Nazia , Naz Iffat , Ali Muhammad Ishtiaq , Ali Naeem , Jamal Asif , Hameed Abdul , Ahmed Safia
Published: October 2013

Biofilms contain a diverse range of microorganisms and their varying extracellular polysaccharides. The present study has revealed biofilm succession associated with degradative effects on plastic (polypropylene) and contaminants in sludge. The wet weight of biofilm significantly (p < 0.05) increased; from 0.23 ± 0.01 to 0.44 ± 0.01 g. Similarly, the dry weight of the biofilm increased from 0.02 to 0.05 g. Significant reduction in pathogens (E. coli and feacal coliforms) by MPN technique (>80%) and in chemical parameters (decrease in COD, BOD5 of 73.32 and 69.94%) representing diminution of organic pollutants. Energy dispersive X‐ray spectroscopy (EDS) of plastic revealed carbon and oxygen contents, further surface analysis of plastic by scanning electron microscopy (SEM) revealed emergence of profound bacterial growth on the surface. Fourier transform infrared (FTIR) spectroscopy conforms its biotransformation under aerobic conditions after 8 weeks. New peaks developed at the region 1050 and 969 cm−1 indicating CO and CC bond formation. Thus plastic with 6 weeks old aerobic biofilm (free of pathogens, max. weight, and OD, efficient COD & BOD removal ability) is suggested to be maintained in fixed biofilm reactors for wastewater treatment.
Multivariate optimization of surfactant‐assisted directly suspended droplet microextraction combined with GC for the preconcentration and determination of tramadol in biological samples
Authors: Ebrahimzadeh Homeira , Mollazadeh Narges , Asgharinezhad Ali Akbar , Shekari Nafiseh , Mirbabaei Fatemeh
Published: October 2013

In this work, a novel procedure based on surfactant‐assisted directly suspended droplet microextraction for the determination of tramadol prior to GC with flame ionization detection is proposed. In this technique, a free microdroplet of solvent is transferred to the surface of an immiscible aqueous sample containing Triton X‐100 and tramadol while being agitated by a stirring bar placed on the bottom of the sample vial. After the predetermined time, the microdroplet of solvent is withdrawn by a syringe and analyzed. The effective parameters such as the type of organic solvent, extraction time, microdroplet volume, salt content of the donor phase, stirring speed, the source phase pH, concentration of Triton X‐100, and extraction temperature were optimized. For this purpose, a multivariate strategy was applied based on an experimental design in order to screen and optimize the significant factors. This method requires minimal sample preparation, analysis time, solvent consumption, and represents significant advantages over customary analytical methods. The linearity ranged from 10 to 2000 μg/L with RSDs (n = 5) of 7.3–10. Preconcentration factors and the LODs were 391–466 and 2.5–6.5 μg/L, respectively. Finally, this method was applied to the analysis of biological samples and satisfactory results were obtained.
Trace analysis of alkaline flavors in cut tobacco by heart‐cutting multidimensional GC–GC–MS
Authors: Wang Xiaoyu , Liu Shaofeng , Xia Qiaoling , Zhao Ge , Guo Jizhao , Xie Fuwei
Published: October 2013

Tobacco is a complex chemical matrix. The analysis of trace alkaline flavors in tobacco is very difficult because of the limited peak capacity of monodimensional GC. In the present study, a home‐assembled twin‐oven GC–GC–MS system, with MS detection in both dimensions, has been applied to the analysis of 20 alkaline volatiles in a variety of cut‐tobacco samples. By transferring nine and six heart‐cuts from the first apolar column to the second polar column in two separate runs, the potential mutual interference of adjacent isomeric targets and the complex matrix could be removed. For comparative purposes, a systematic comparison of both quantification and qualification results for the cut‐tobacco sample as quality control was conducted between GC–GC–MS and GC–MS. The results showed that GC–GC–MS provided higher accuracy in peak assignment and quantification. And in GC–MS, the interferences of co‐elution had caused both low matched similarity in peak assignment and false‐negative/‐positive results in quantification for some targets. Advantages of the developed GC–GC–MS method in the analysis of alkaline flavors are its high resolving power, reliability, and simplicity.
Photonic‐on‐a‐chip: a thermal actuated Mach‐Zehnder interferometer and a molecular thermometer based on a single di‐ureasil organic‐inorganic hybrid
Authors: Ferreira Rute A. S. , Brites Carlos D S. , Vicente Carlos M. S. , Lima Patrícia P. , Bastos Ana R. N. , Marques Paulo G. , Hiltunen Marianne , Carlos Luis D. , André Paulo S.
Published: October 2013

An integrated photonic‐on‐a‐chip device based on a single organic‐inorganic di‐ureasil hybrid was fabricated for optical waveguide and temperature sensing. The device is composed by a thermal actuated Mach‐Zehnder (MZ) interferometer operating with a switching power of 0.011 W and a maximum temperature difference between branches of 0.89 ºC. The MZ interferometer is covered by a Eu3+/Tb3+ co‐doped di‐ureasil luminescent molecular thermometer with a temperature uncertainty of 0.1ºC and a spatial resolution of 13 µm. This is an uncommon example in which the same material (an organic‐inorganic hybrid) that is used to fabricate a particular device (a thermal‐actuated MZ interferometer) is also used to measure one of the device intrinsic properties (the operating temperature). The photonic‐on‐a‐chip example discussed here can be applied to sense temperature gradients with high resolution (10−3 ºC·µm−1) in chip‐scale heat engines or refrigerators, magnetic nanocontacts and energy‐harvesting machines.
Apparent singular points of factors of reducible generalized hypergeometric equations
Authors: Ebisu Akihito
Published: October 2013

We consider a reducible generalized hypergeometric equation, whose sub‐equation possesses apparent singular points. We determine the polynomial whose roots are these points. We show that this polynomial is a generalized hypergeometric polynomial.