bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous Adsorptive Cathodic Stripping Voltammetric Determination of Nickel(II) and Cobalt(II) at an In Situ Bismuth‐Modified Gold Electrode
Authors: Mardegan A. , Dal Borgo S. , Scopece P. , Moretto L. M. , Hočevar S. B. , Ugo P. 
Published: October 2013

AbstractA study on the simultaneous determination of Ni(II) and Co(II) dimethylglyoximates (Ni‐DMG and Co‐DMG) through adsorptive cathodic stripping voltammetry at an in situ bismuth‐modified gold electrode (Bi‐AuE) is reported. The key operational parameters, such as Bi(III) concentration, accumulation potential and accumulation time were optimized and the morphology of the Bi‐microcrystals deposited on the Au‐electrode was studied. The Bi‐AuE allowed convenient analysis of trace concentrations of solely Ni(II) or of Ni(II) and Co(II) together, with cathodic stripping voltammograms characterized by well‐separated stripping peaks. The calculated limit of detection (LOD) was 40 ng L−1 for Ni(II) alone, whereas the LOD was 98 ng L−1 for Ni(II) and 58 ng L−1 for Co(II), when both metal ions were measured together. The optimized method was finally applied to the analysis of certified spring water (NIST1640a) and of natural water sampled in the Lagoon of Venice. The results obtained with the Bi‐AuE were in satisfactory agreement with the certified values and with those provided by complementary techniques, i.e., ICP‐OES and ICP‐MS.
A Facile One‐Step Method for the Synthesis of Reduced Graphene Oxide Nanocomposites by NADH as Reducing Agent and Its Application in NADH Sensing
Authors: Tabrizi Mahmoud Amouzadeh , Zand Zahra 
Published: October 2013

AbstractHere, we report a green and eco‐friendly approach to synthesize reduced graphene oxide (rGO) via a mild hydrothermal process using nicotinamide adenine dinucleotide (NADH) as a reducing agent. The obtained rGO was characterized by UV‐visible absorption spectroscopy (UV‐vis), X‐ray diffraction spectroscopy, atomic force microscopy (AFM) and scanning electron microscopy (SEM). Electrochemical experiments indicated that the rGO/GC electrode exhibited an excellent electrocatalytic activity towards the oxidation of NADH, which can be attributed to the excellent electrical conductivity and high specific surface area of the rGO composite. The resulting biosensor showed highly sensitive amperometric response to NADH with a low detection limit (0.6 µM).
Point of care creatinine measurement for diagnosis of renal disease using a disposable microchip
Authors: Ávila Mónica , Floris Arjan , Staal Steven , Ríos Ángel , Eijkel Jan , van den Berg Albert 
Published: October 2013

A point‐of‐care device for the determination of elevated creatinine levels in blood is reported. This device potentially offers a new and simple clinical regime for the determination of creatinine that will give huge time savings and removal of several steps of determination. The test employs a disposable prefilled microchip and the handheld Medimate Multireader®. By optimizing the analytical conditions it was found that the LOD of the proposed method was 87 μM creatinine, close to the normal human serum levels that are in the range of 60 to 100 μM. A statistical analysis of the residual shows a normal distribution, indicating the absence of systematic errors in the proposed method. The test can be used to distinguish patients with renal insufficiency (creatinine levels >100 μM) from healthy persons. Long‐term monitoring could furthermore distinguish between acute renal failure and chronic kidney disease by the rate of creatinine concentration rise.
Sensitive determination of positional isomers of benzenediols in human urine by boronate affinity capillary electrophoresis with chemiluminescence detection
Authors: Lin Zian , Sun Xiaobo , Hu Wenli , Yin Yuqing , Chen Guonan 
Published: October 2013

A boronate ACE coupled with chemiluminescence (CL) detection was developed for sensitive determination of three isomeric benzenediols, which was based on the principle of an inhibited effect of borate complexation on the CL reaction between luminol and potassium hexacyanoferrate (K3Fe(CN)6) in alkaline solution. The effects of some important factors on CE separation and CL intensity were systemically investigated. Baseline separation of isomeric benzenediols including o‐benzenediol, m‐benzenediol, and p‐benzenediol was achieved by using a mobile phase of 40 mmol/L glycine–NaOH buffer at pH 9.4 containing 0.8 mmol/L luminol and 0.4 mol/L 4‐iodophenylboronic acid. The calibration curves of the analytes by plotting the peak height against corresponding concentration were linear over the range of 4.5 × 10−8 ∼ 4.5 × 10−5 mol/L for p‐benzenediol, 6.8 × 10−8 ∼ 2.7 × 10−5 mol/L for m‐benzenediol, and 9.0 × 10−8 ∼ 4.5 × 10−5 mol/L for o‐benzenediol. The corresponding detection limits for p‐, m‐, and o‐benzenediols were 2.8 × 10−8 mol/L (68 amol), 3.2 × 10−8 mol/L (108.4 amol), and 3.7 × 10−8 mol/L (125.8 amol; S/N = 3), respectively. The proposed method has been successfully applied to the analysis of trace benzenediols in spiked human urine sample and the recoveries were >97.2%. Our primary result demonstrated the proposed CE‐CL method has great potential for biomarker determination in clinical diagnosis.
N‐methyl‐2‐pyrrolidonium methyl sulfonate acidic ionic liquid as a new dynamic coating for separation of basic proteins by capillary electrophoresis
Authors: Guo Xiao‐Feng , Chen Hui‐Ying , Zhou Xiao‐Hai , Wang Hong , Zhang Hua‐Shan 
Published: October 2013

A simple and economical CE method has been developed for the analysis of four model basic proteins by employing N‐methyl‐2‐pyrrolidonium methyl sulfonate ionic liquid (IL) as the dynamic coating material based on the interaction of both between electrostatic attraction and hydrogen bond, and between the organic cations of IL and the inner surface of bare fused‐silica capillary. The N‐methyl‐2‐pyrrolidonium‐based IL modified capillary not only generated a stable suppressed electroosmotic flow, but also effectively eliminated the wall adsorption of proteins. Several important parameters such as the IL concentration, pH values, and concentrations of the background electrolyte were optimized to improve the separation of basic proteins. Consequently, under the optimum separation conditions, a satisfied separation of basic proteins including lysozyme, cytochrome c, ribonuclease A, and α‐chymotrypsinogen A with theoretical plates ranging from 2.09 × 105 to 4.48 × 105 plates/m had been accomplished within 15 min. The proposed method first illustrated the effect of hydrogen bond between coating material and inner capillary surface on the coating, which should be a new strategy to design and select more effective coating materials to form more stable coatings in CE.
mRNA 3′end processing: A tale of the tail reaches the clinic
Authors: Hollerer Ina , Grund Kerstin , Hentze Matthias W. , Kulozik Andreas E 
Published: October 2013

AbstractRecent advances reveal mRNA 3′end processing as a highly regulated process that fine‐tunes posttranscriptional gene expression. This process can affect the site and/or the efficiency of 3′end processing, controlling the quality and the quantity of substrate mRNAs. The regulation of 3′end processing plays a central role in fundamental physiology such as blood coagulation and innate immunity. In addition, errors in mRNA 3′end processing have been associated with a broad spectrum of human diseases, including cancer. We summarize and discuss the paradigmatic shift in the understanding of 3′end processing as a mechanism of posttranscriptional gene regulation that has reached clinical medicine.
Optimization and Analysis of High‐Power Hydrogen/Bromine‐Flow Batteries for Grid‐Scale Energy Storage
Authors: Cho Kyu Taek , Albertus Paul , Battaglia Vincent , Kojic Aleksandar , Srinivasan Venkat , Weber Adam Z. 
Published: October 2013

AbstractFor storage of grid‐scale electrical energy, redox‐flow batteries (RFBs) are considered promising technologies. This paper explores the influence of electrolyte composition and ion transport on cell performance by using an integrated approach of experiments and cost modeling. In particular, the impact of the area‐specific resistance on system capability is elucidated for the hydrogen/bromine RFB. The experimental data demonstrate very good performance with 1.46 W cm−2 peak power and 4 A cm−2 limiting current density at ambient conditions for an optimal cell design and reactant concentrations. The data and cost model results show that higher concentrations of RFB reactants do not necessarily result in lower capital cost as there is a tradeoff between cell performance and storage (tank) requirements. In addition, the discharge time and overall efficiency demonstrate nonlinear effects on system cost, with a 3 to 4 hour minimum discharge time showing a key transition to a plateau in terms of cost for typical RFB systems. The presented results are applicable to many different RFB chemistries and technologies and highlight the importance of ohmic effects and associated area‐specific resistance on RFB viability.
Nonlinear response estimates of RC frames using linear analysis of SDOF systems
Authors: Yaghmaei‐Sabegh Saman , Neekmanesh Shabnam , Lumantarna Elisa 
Published: October 2013

SUMMARYAn approximate‐simple method for nonlinear response estimates of reinforced concrete frames subjected to near‐field and far‐field records is presented in this paper. The approximate method is based on equivalent single‐degree‐of‐freedom and linear multi‐degree‐of‐freedom models. In this procedure, the nonlinear maximum roof displacement is estimated using an effective period factor and elastic response spectrum with an equivalent damping. The effective period factor was proposed for far‐field and near‐field ground motion records. For regions of high seismicity, the maximum roof displacement can be estimated by applying an effective period factor of 2.3 and 2.1 for near‐field and far‐field records, respectively, and 9% damped displacement response spectrum. For regions of moderate seismicity, a lower effective period factor of 1.9 and 1.8, for near‐field and far‐field records, respectively, can be applied to estimate the maximum roof displacement. A relationship between linear and nonlinear response of multi‐degree‐of‐freedom systems was also proposed to obtain estimates of the maximum inter‐story drift of nonlinear responding reinforced concrete frames. In addition, the effects of number of ground motion records used in the analyses on the scatters of results were investigated. The required number of ground motions to produce a reliable response was proposed. Copyright © 2013 John Wiley & Sons, Ltd.
Post‐fire bedload sediment delivery across spatial scales in the interior western United States
Authors: Wagenbrenner Joseph W. , Robichaud Peter R. 
Published: October 2013

ABSTRACTPost‐fire sediment yields can be up to three orders of magnitude greater than sediment yields in unburned forests. Much of the research on post‐fire erosion rates has been at small scales (100 m2 or less), and post‐fire sediment delivery rates across spatial scales have not been quantified in detail. We developed relationships for post‐fire bedload sediment delivery rates for spatial scales up to 117 ha using sediment yield data from six published studies and two recently established study sites. Sediment yields and sediment delivery ratios (SDRs; sediment delivered at the catchment scale divided by the sediment delivered from a plot nested within the catchment) were related to site factors including rainfall characteristics, area, length, and ground cover. Unit‐area sediment yields significantly decreased with increasing area in five of the six sites. The annual SDRs ranged from 0.0089 to 1.15 and these were more closely related to the ratio of the plot lengths than the ratio of plot areas. The developed statistical relationships will help quantify post‐fire sediment delivery rates across spatial scales in the interior western United States and develop process‐based scaling relationships. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.
A new approach for the laboratory culture of the fathead minnow, Pimephales promelas
Authors: Gordon Denise A. , Smith Mark E. , Wratschko Melissa , Agard David , Holden Lisa , Wilcox Steve , Lazorchak James M. 
Published: October 2013

Abstract

Fathead minnows are routinely cultured for use in aquatic toxicology studies. A new mass culture system described in the present study consisted of 6 stainless steel tanks, each containing 68 fish and 20 spawning substrates. Spawning results are compared with a previous system of 22 individual glass aquaria, which contained 16 fish and 4 spawning substrates per tank. During a 19-mo period, the new system produced an average of 4105 eggs/d, compared with an average of 2465 eggs/d with the previous system. Labor and maintenance were reduced with the new system. The stainless steel tanks eliminated aquaria glass breakage, and daily water use was reduced by 45%. Analysis of reference toxicant data from fish cultured using both systems indicated no change in the sensitivity of the test animals. Analyses of 2009 egg production data determined that a 6:1 to 7:1 female to male ratio had a significantly positive impact on egg production levels and that 6-mo-old breeding stock should be introduced to the spawning tanks in mid-spring for optimal egg production during the rest of the year. Implementing a stainless steel mass culture system significantly increased efficiency of egg production; reduced turnaround delay of mature animal availability for toxicity and molecular testing; and reduced labor time, costs, and inherent safety hazards, compared with glass aquaria systems. Environ Toxicol Chem 2014;33:126–133. © 2013 SETAC
The impact of municipal wastewater effluent on field-deployed freshwater mussels in the Grand River (Ontario, Canada)
Authors: Gillis Patricia L. , Gagné François , McInnis Rodney , Hooey Tina M. , Choy Emily S. , André Chantale , Hoque Md Ehsanul , Metcalfe Chris D. 
Published: October 2013

Abstract

To examine effects of municipal wastewater effluent (MWWE) on sentinel organisms, the authors deployed caged freshwater mussels (Lasmigona costata) in the Grand River (ON, Canada) upstream and downstream of an MWWE outfall. Passive sampling devices were deployed alongside caged mussels to confirm exposure. Biomarkers of xenobiotic biotransformation, oxidative stress, estrogenicity, and immunomodulation were investigated. Elevated concentrations of selected pharmaceutical and personal care products (PPCPs) and a natural estrogen (estrone) were found at the downstream sites. Mussels caged downstream of the effluent for 2 wk showed minimal evidence of exposure, while those deployed for 4 wk exhibited significantly higher levels of lipid peroxidation (LPO) and glutathione S-transferase (GST) activity, demonstrating that MWWE-exposed mussels exhibit increased activity in xenobiotic conjugation and oxidative stress. With respect to immune responses, a significant increase in plasma lysozyme activity and hemocyte viability was observed in MWWE-exposed mussels. Vitellogenin (vtg)-like protein in male mussels showed a trend toward induction after 4 wk of deployment at the first downstream site, but mean levels were not significantly different. Discriminant function analysis indicated that mussels deployed for 4 wk upstream and downstream of the MWWE discharge could be discriminated on the basis of LPO, GST, plasma lysozyme, and vtg responses. The physiological stress observed in caged mussels indicates that wild mussels chronically exposed to MWWE in this ecosystem would also be negatively impacted. Environ Toxicol Chem 2014;33:134–143. © 2013 SETAC
Age-related polychlorinated biphenyl dynamics in immature bull sharks (Carcharhinus leucas)
Authors: Olin Jill A. , Beaudry Marina , Fisk Aaron T. , Paterson Gordon 
Published: October 2013

Abstract

Polychlorinated biphenyls (PCBs) were quantified in liver tissues of bull sharks (Carcharhinus leucas) ranging in age from &lt;4 wk to &gt;3 yr. Summed values of PCBs (ΣPCBs) ranged from 310 ng/g to 22 070 ng/g (lipid wt) across age classes with ΣPCB concentrations for the youngest sharks in the present study (&lt;4 wk; 5230 ± 2170 ng/g lipid wt) determined to not significantly differ from those quantified in &gt;3-yr-old sharks, highlighting the extent of exposure of this young life stage to this class of persistent organic pollutants (POPs). Age normalization of PCB congener concentrations to those measured for the youngest sharks demonstrated a significant hydrophobicity (log octanol/water partition coefficient [KOW]) effect that was indicative of maternal offloading of highly hydrophobic (log KOW ≥6.5) congeners to the youngest individuals. A distinct shift in the PCB congener profiles was also observed as these young sharks grew in size. This shift was consistent with a transition from the maternally offloaded signal to the initiation of exogenous feeding and the contributions of mechanisms including growth dilution and whole-body elimination. These results add to the growing pool of literature documenting substantially high concentrations of POPs in juvenile sharks that are most likely attributable to maternal offloading. Collectively, such results underscore the potential vulnerability of young sharks to POP exposure and pose additional concerns for shark-conservation efforts. Environ Toxicol Chem 2014;33:35–43. © 2013 SETAC
Investigating Alternatives to the fish early-life stage test: A strategy for discovering and annotating adverse outcome pathways for early fish development
Authors: Villeneuve Daniel , Volz David C. , Embry Michelle R. , Ankley Gerald T. , Belanger Scott E. , Léonard Marc , Schirmer Kristin , Tanguay Robert , Truong Lisa , Wehmas Leah 
Published: October 2013

Abstract

The fish early-life stage (FELS) test (Organisation for Economic Co-operation and Development [OECD] test guideline 210) is the primary test used internationally to estimate chronic fish toxicity in support of ecological risk assessments and chemical management programs. As part of an ongoing effort to develop efficient and cost-effective alternatives to the FELS test, there is a need to identify and describe potential adverse outcome pathways (AOPs) relevant to FELS toxicity. To support this endeavor, the authors outline and illustrate an overall strategy for the discovery and annotation of FELS AOPs. Key events represented by major developmental landmarks were organized into a preliminary conceptual model of fish development. Using swim bladder inflation as an example, a weight-of-evidence–based approach was used to support linkage of key molecular initiating events to adverse phenotypic outcomes and reduced young-of-year survival. Based on an iterative approach, the feasibility of using key events as the foundation for expanding a network of plausible linkages and AOP knowledge was explored and, in the process, important knowledge gaps were identified. Given the scope and scale of the task, prioritization of AOP development was recommended and key research objectives were defined relative to factors such as current animal-use restrictions in the European Union and increased demands for fish toxicity data in chemical management programs globally. The example and strategy described are intended to guide collective efforts to define FELS-related AOPs and develop resource-efficient predictive assays that address the toxicological domain of the OECD 210 test. Environ Toxicol Chem 2014;33:158–169. © 2013 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited.
Optical bioassay for measuring sublethal toxicity of insecticides in Daphnia pulex
Authors: Zein Maya A. , McElmurry Shawn P. , Kashian Donna R. , Savolainen Peter T. , Pitts David K. 
Published: October 2013

Abstract

Many emerging contaminants tend to be biologically active at very low concentrations, occur in water as part of complex mixtures, and impact biota in ways that are not detected using traditional toxicity tests (e.g., median lethal concentration). To evaluate emerging contaminants, the authors developed a method for detecting sublethal behavioral effects by quantifying the swimming behavior of Daphnia pulex, a model organism for studying aquatic toxicity. This optical tracking technique is capable of measuring many swimming parameters, 2 of which—cumulative distance and angular change—are presented. To validate this technique, 2 prototypical compounds that exhibit different modes of action as well as corresponding insecticides that are commonly found in surface waters were investigated. The acetylcholinesterase (AChE) inhibitor physostigmine was used as the prototypical compound for the large number of AChE inhibitor insecticides (e.g., chlorpyrifos). Nicotine was used as the prototypical compound for neonicotinoid insecticides (e.g., imidacloprid). Results demonstrate that this assay is capable of detecting sublethal behavioral effects that are concentration-dependent and that insecticides with the same mode of action yield similar results. The method can easily be scaled up to serve as a high-throughput screening tool to detect sublethal toxic effects of a variety of chemicals. This method is likely to aid in enhancing the current understanding of emerging contaminants and to serve as a novel water-quality screening tool. Environ Toxicol Chem 2014;33:144–151. © 2013 SETAC
Does a concomitant exposure to lead influence unfavorably the naphthalene subchronic toxicity and toxicokinetics?
Authors: Katsnelson Boris A. , Minigaliyeva Ilzira A. , Degtyareva Tamara D. , Privalova Larisa I. , Beresneva Tatyana A. 
Published: October 2013

Abstract

Rats were given 20 times during 40 d either naphthalene per gavage or the same and lead acetate intraperitoneally in single doses corresponding to 5% of the respective 50% lethal doses. The concomitant exposure to lead not only added some typical indicators of lead toxicity to the moderate naphthalene intoxication picture but also exaggerated some less specific indices for intoxication. However, a number of such indices testified to attenuation of naphthalene's adverse effects under the impact of lead. Lead also lowered urinary excretion of both total and conjugated naphthalene, while the free- to total naphthalene ratio in urine sharply increased. These results corroborate implicitly the initial hypothesis that lead, being an inhibitor of cytochrome P450, hinders phase I of the naphthalene biotransformation and, thus, the formation of derivates which can be more toxic but are capable of entering into reactions of conjugation with resulting detoxication and elimination of naphthalene from the body. Environ Toxicol Chem 2014;33:152–157. © 2013 SETAC