bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrochemical Quartz Crystal Microbalance with Dissipation Monitoring: A Technique to Optimize Enzyme Use in Bioelectrocatalysis
Authors: Singh Kulveer , Blanford Christopher F. 
Published: April 2014

AbstractThis Concept article outlines how an electrochemical quartz crystal microbalance with dissipation monitoring (E‐QCM‐D) is used as a tool to follow adsorption and inactivation processes of immobilised oxidoreductases and to determine their specific activity simultaneously. Plots that relate activity to the adsorbed mass and dissipation have distinct features that can be used to diagnose the mechanisms of long‐term activity loss. Along with model plots, this article highlights some of the key advances made by using the technique and how it has been applied to biocatalytic processes in which electrons are transferred directly between an electrode and an immobilised enzyme.
Understanding the Fundamental Role of π/π, σ/σ, and σ/π Dispersion Interactions in Shaping Carbon‐Based Materials
Authors: Alonso Mercedes , Woller Tatiana , Martín‐Martínez Francisco J. , Contreras‐García Julia , Geerlings Paul , De Proft Frank 
Published: April 2014

AbstractNoncovalent interactions involving aromatic rings, such as π‐stacking and CH/π interactions, are central to many areas of modern chemistry. However, recent studies proved that aromaticity is not required for stacking interactions, since similar interaction energies were computed for several aromatic and aliphatic dimers. Herein, the nature and origin of π/π, σ/σ, and σ/π dispersion interactions has been investigated by using dispersion‐corrected density functional theory, energy decomposition analysis, and the recently developed noncovalent interaction (NCI) method. Our analysis shows that π/π and σ/σ stacking interactions are equally important for the benzene and cyclohexane dimers, explaining why both compounds have similar boiling points. Also, similar dispersion forces are found in the benzene⋅⋅⋅methane and cyclohexane⋅⋅⋅methane complexes. However, for systems larger than naphthalene, there are enhanced stacking interactions in the aromatic dimers adopting a parallel‐displaced configuration compared to the analogous saturated systems. Although dispersion plays a decisive role in stabilizing all the complexes, the origin of the π/π, σ/σ, and σ/π interactions is different. The NCI method reveals that the dispersion interactions between the hydrogen atoms are responsible for the surprisingly strong aliphatic interactions. Moreover, whereas σ/σ and σ/π interactions are local, the π/π stacking are inherently delocalized, which give rise to a non‐additive effect. These new types of dispersion interactions between saturated groups can be exploited in the rational design of novel carbon materials.
The longitudinal impact of patient navigation on equity in colorectal cancer screening in a large primary care network
Authors: Percac‐Lima Sanja , López Lenny , Ashburner Jeffrey M. , Green Alexander R. , Atlas Steven J. 
Published: April 2014

BACKGROUNDThe long‐term effects of interventions to improve colorectal (CRC) screening in vulnerable populations are uncertain. The authors evaluated the impact of patient navigation (PN) on the equity of CRC prevention over a 5‐year period.METHODSA culturally tailored CRC screening PN program was implemented in 1 community health center (CHC) in 2007. In a primary care network, CRC screening rates from 2006 to 2010 among eligible patients from the CHC with PN were compared with the rates from other practices without PN. Multivariable logistic regression models for repeated measures were used to assess differences over time.RESULTSDifferences in CRC screening rates diminished among patients at the CHC with PN and at other practices between 2006 (49.2% vs 62.5%, respectively; P < .001) and 2010 (69.2% vs 73.6%, respectively; P < .001). The adjusted rate of increase over time was higher at the CHC versus other practices (5% vs 3.4% per year; P < .001). Among Latino patients at the CHC compared with other practices, lower CRC screening rates in 2006 (47.5% vs 52.1%, respectively; P = .02) were higher by 2010 (73.5% vs 67.3%, respectively; P < .001). Similar CRC screening rates among non‐English speakers at the CHC and at other practices in 2006 (44.3% vs 44.7%, respectively; P = .79) were higher at the CHC by 2010 (70.6% vs 58.6%, respectively; P < .001). Adjusted screening rates increased more over time for Latino and non‐English speakers at the CHC compared with other practices (both P < .001).CONCLUSIONSA PN program increased CRC screening rates in a CHC and improved equity in vulnerable patients. Long‐term funding of PN programs has the potential to reduce cancer screening disparities. Cancer 2014;120:2025–2031. © 2014 American Cancer Society.
Thermal Expansion, Anharmonicity and Temperature‐Dependent Raman Spectra of Single‐ and Few‐Layer MoSe2 and WSe2
Authors: Late Dattatray J. , Shirodkar Sharmila N. , Waghmare Umesh V. , Dravid Vinayak P. , Rao C. N. R. 
Published: April 2014

AbstractWe report the temperature‐dependent Raman spectra of single‐ and few‐layer MoSe2 and WSe2 in the range 77–700 K. We observed linear variation in the peak positions and widths of the bands arising from contributions of anharmonicity and thermal expansion. After characterization using atomic force microscopy and high‐resolution transmission electron microscopy, the temperature coefficients of the Raman modes were determined. Interestingly, the temperature coefficient of the A22u mode is larger than that of the A1g mode, the latter being much smaller than the corresponding temperature coefficients of the same mode in single‐layer MoS2 and of the G band of graphene. The temperature coefficients of the two modes in single‐layer MoSe2 are larger than those of the same modes in single‐layer WSe2. We have estimated thermal expansion coefficients and temperature dependence of the vibrational frequencies of MoS2 and MoSe2 within a quasi‐harmonic approximation, with inputs from first‐principles calculations based on density functional theory. We show that the contrasting temperature dependence of the Raman‐active mode A1g in MoS2 and MoSe2 arises essentially from the difference in their strain–phonon coupling.
Modeling Practical Performance Limits of Photoelectrochemical Water Splitting Based on the Current State of Materials Research
Authors: Seitz Linsey C. , Chen Zhebo , Forman Arnold J. , Pinaud Blaise A. , Benck Jesse D. , Jaramillo Thomas F. 
Published: April 2014

AbstractPhotoelectrochemical (PEC) water splitting is a means to store solar energy in the form of hydrogen. Knowledge of practical limits for this process can help researchers assess their technology and guide future directions. We develop a model to quantify loss mechanisms in PEC water splitting based on the current state of materials research and calculate maximum solar‐to‐hydrogen (STH) conversion efficiencies along with associated optimal absorber band gaps. Various absorber configurations are modeled considering the major loss mechanisms in PEC devices. Quantitative sensitivity analyses for each loss mechanism and each absorber configuration show a profound impact of both on the resulting STH efficiencies, which can reach upwards of 25 % for the highest performance materials in a dual stacked configuration. Higher efficiencies could be reached as improved materials are developed. The results of the modeling also identify and quantify approaches that can improve system performance when working with imperfect materials.
Isolated Boron and Nitrogen Sites on Porous Graphitic Carbon Synthesized from Nitrogen‐Containing Chitosan for Supercapacitors
Authors: Sun Li , Fu Yu , Tian Chungui , Yang Ying , Wang Lei , Yin Jie , Ma Jing , Wang Ruihong , Fu Honggang 
Published: April 2014

AbstractSeparated boron and nitrogen porous graphitic carbon (BNGC) is fabricated by a facile hydrothermal coordination/ZnCl2‐activation process from renewable and inexpensive nitrogen‐containing chitosan. In this synthetic pathway, chitosan, which has a high nitrogen content, first coordinates with Fe3+ ions to form chitosan–Fe that subsequently reacts with boric acid (boron source) to generate the BNGC precursor. After simultaneous carbonization and ZnCl2 activation followed by removal of the Fe catalyst, BNGC, containing isolated boron and nitrogen centers and having a high surface area of 1567 m2 g−1 and good conductivity, can be obtained. Results indicate that use of chitosan as a nitrogen‐containing carbon source effectively prevents nitrogen atoms from direct combination with boron atoms. In addition, the incorporation of Fe3+ ions not only endows BNGC with high graphitization, but also favors for nitrogen fixation. Remarkably, the unique microstructure of BNGC enables its use as an advanced electrode material for energy storage. As electrode material for supercapacitors, BNGC shows a high capacitance of 313 F g−1 at 1 A g−1, and also long‐term durability and coulombic efficiency of >99.5 % after 5000 cycles. Notably, in organic electrolytes, the energy density could be up to 50.1 Wh kg−1 at a power density of 10.5 kW kg−1. The strategy developed herein opens a new avenue to prepare BNGC without inactive BN bonds from commercially available chitosan for high‐performance supercapacitors.
Implementation of the bethesda system for reporting thyroid cytopathology: Interobserver concordance and reclassification of previously inconclusive aspirates
Authors: Pathak Priya , Srivastava Ruchi , Singh Navjeevan , Arora Vinod K. , Bhatia Arati 
Published: April 2014

Standardized diagnostic terminology was introduced by the Bethesda System for Reporting Thyroid Cytopathology (BSRTC) in an effort to bring uniformity to the reporting of thyroid cytopathology, provide more defined categories to enable clinical management, and minimize the number of inconclusive cases. Previous studies indicate that the BSRTC is a reliable and valid reporting system for thyroid cytology.This study was conducted to compare the concordance between observers with varying cytopathology experience when using the BSRTC, and to assess the impact on the number of inconclusive reports.A retrospective study was conducted in two parts. In the first part 415 thyroid aspirates were reviewed independently by three observers with different experience levels. The aspirates were reclassified according to BSRTC and agreement scores were calculated using kappa statistics. In the second part 39 inconclusive aspirates signed out previously, were recategorized according to BSRTC.Agreement level between the three observers using the BSRTC was strong (Fleiss' kappa score = 0.6561). Inconclusive cases could be categorized further with BSRTC; there was significant reduction in the number of inconclusive diagnoses (P < 0.001).Strong interobserver agreement with BSRTC indicates the ease with which the new system can be applied in regular reporting. Significant reduction in the number of inconclusive diagnoses results in better communication with the clinician and improved risk assessment for thyroid aspirates. Diagn. Cytopathol. 2014;42:944–949. © 2014 Wiley Periodicals, Inc.
Phosphorus Chemistry
Authors: Caporali Maria 
Published: March 2014

AbstractAn overview of the papers in this cluster issue is presented.“...Since its discovery, much progress has been made, and nowadays the chemistry of phosphorus rivals that of carbon. The variety of compounds finds a plethora of applications not only as ligand in the rich field of coordination chemistry and catalysis, but also as organophosphorus building blocks opening new avenues towards fascinating and highly functionalized materials.”Read more by the Guest Editor on p. 1565.
Polyunsaturated fatty acids modify expression of TGF‐β in a co‐culture model ultilising human colorectal cells and human peripheral blood mononuclear cells exposed to Lactobacillus gasseri, Escherichia coli and Staphylococcus aureus
Authors: Bentley‐Hewitt Kerry L , De Guzman Cloe Erika , Ansell Juliet , Mandimika Tafadzwa , Narbad Arjan , Lund Elizabeth K 
Published: March 2014

Commensal bacteria and polyunsaturated fatty acids (PUFAs) have both been shown independently to modulate immune responses. This study tested the hypothesis that the different colonic immunomodulatory responses to commensal (Lactobacillus gasseri) and pathogenic bacteria (Escherichia coli and Staphylococcus aureus) may be modified by PUFAs. Experiments used a Transwell system combining the colorectal cell line HT29, or its mucous secreting sub‐clone HT29‐MTX, with peripheral blood mononuclear cells to analyse immunomodulatory signalling in response to bacteria, with and without prior treatment with arachidonic acid, eicosapentaenoic acid or docosahexaenoic acid. L. gasseri increased transforming growth factor β1 (TGF‐β1) mRNA and protein secretion in colonic cell lines when compared with controls, an effect that was enhanced by pre‐treatment with eicosapentaenoic acid. In contrast, the Gram‐negative pathogen E. coli LF82 had no significant effect on TGF‐β1 protein. L. gasseri also increased IL‐8 mRNA but not protein while E. coli increased both; although differences between PUFA treatments were detected, none were significantly different to controls. Colonic epithelial cells show different immunomodulatory signalling patterns in response to the commensal L. gasseri compared to E. coli and S. aureus and pre‐treatment of these cells with PUFAs can modify responses.Practical applications: We have demonstrated an interaction between dietary PUFAs and epithelial cell response to both commensal and pathogenic bacteria found in the gastrointestinal tract by utilising in vitro co‐culture models. The data suggest that n‐3 PUFAs may provide some protection against the potentially damaging effects of pathogens. Furthermore, the beneficial effects of combining n‐3 PUFAs and the commensal bacteria, and potential probiotic, L. gasseri are illustrated by the increased expression of immunoregulatory TGF‐β1.
Role of aeolian sediment accretion in the formation of heuweltjie earth mounds, western South Africa
Authors: McAuliffe Joseph R. , Timm Hoffman M. , McFadden Leslie D. , King Matthew P. 
Published: April 2014

ABSTRACTThe action of organisms in shaping landforms is increasingly recognized; the field of biogeomorphology and the conceptual framework of ecosystem engineering have arisen in response to the need for integrated studies of the interactions between biotic and abiotic components of landscapes. Pathways by which organisms influence landscape development may be complex. For example, primary change initiated by one biotic element may initiate a cascade of other changes that eventually produce a significant landscape modification. Mound‐like landforms in North America and southern Africa are widely cited examples of biogenic structures, yet there is considerable controversy regarding the processes responsible for their formation. Heuweltjies (Afrikaans for little hills) are circular mounds ranging from 10–30 m diameter and 0.5–2 m height and are widespread in western South Africa. Colonies of the termite (Microhodotermes viator) are typically associated with heuweltjies and some investigators have attributed heuweltjie formation to the direct action of termites in redistributing earthen materials. However, rather than being directly responsible in this way, termites simply create nutrient‐rich islands, which support denser vegetation, thereby inducing the localized accretion of aeolian sediments and upward growth of mounds. Contrasting soil features in heuweltjies in one locale indicate these processes have occurred throughout the late Quaternary. Geographic variation in sizes of mounds is explained in part by the local availability of sediments that can be mobilized and redistributed by the wind. Recognition of the operation of aeolian processes in the formation of heuweltjies has important implications for conservation. Any land use that diminishes the sediment‐trapping effect of vegetation on heuweltjies truncates the very process by which new aeolian materials can accrue and may promote irreversible erosion and landscape degradation. Copyright © 2014 John Wiley & Sons, Ltd.
Comparison of aquatic and dietary exposure of heavy metals Cd, Cu, and Zn to benthic ostracod Heterocypris incongruens
Authors: Sevilla Janice Beltran , Nakajima Fumiyuki , Kasuga Ikuro 
Published: April 2014

Abstract

The benthic ostracod Heterocypris incongruens is becoming an important tool for the ecotoxicological assessment of contaminated sediments. However, no study has yet explored solid-phase (dietary) exposure to ostracod. The present study examined the effects of metals on H. incongruens through aquatic and dietary exposures. The algal food Chlorella vulgaris was exposed to different concentrations of cadmium (Cd), copper (Cu), and zinc (Zn), and subcellular distributions of these metals in algal cells were determined. Parallel experiments were also performed to determine the toxic effects of dissolved metals on ostracod through aqueous exposure. Significant toxic effects on mortality were observed when ostracod were fed with Cd-contaminated (47–100%) and Cu-contaminated algae (55–100%). With increasing accumulated Zn in the algal cell, ostracod mortality also increased (20–83%). Aquatic exposure of ostracod to different concentrations of dissolved Cd (3.2–339 µg Cd/L) and Cu (260–2600 µg Cu/L) resulted in high observed mortalities (57–100% and 95–100%, respectively). Based on the results of aqueous and dietary exposure tests, it can be concluded that both exposure routes are important in evaluating the toxic effect of Cd on ostracod. Similar results were observed in tests using other metals (i.e., using Cu and Zn), thus emphasizing the importance of considering not only aquatic but also dietary exposure routes when evaluating metal toxicity to ostracod. Environ Toxicol Chem 2014;33:1624–1630. © 2014 SETAC
Lessons learnt during construction assistance for the improvement of contract models
Authors: Holzleitner Wolfgang , Kraft‐Fish Martin , Steinacher Reinhold 
Published: April 2014

AbstractThe consultant Bernard Ingenieure has two decades of design, site supervision and technical assistance experience working with Indian contractors on hydropower and infrastructure projects on the Indian subcontinent. This article presents the lessons learnt by the consultant from these projects, in particular the 126 MW Dagachhu Hydropower Project, which is due to be completed in 2014. The article subsequently describes how the consultant has applied regulatory measures in tender documents for its ongoing projects, as well as ideas for further measures to be applied in future contract models.The regulatory measures intrude on what is traditionally considered to be the contractor's sphere of influence, such as selection of plant and equipment, personnel and works sequencing. Since the proposed measures are only as useful as the provisions to enforce their implementation, the fulfilment of contract conditions is linked to payment deductions, which have the aim of encouraging contractors to improve their performance and therefore project outcomes rather than to save cost.Projects in India would benefit from replacing awards based on the lowest price with Quality and Cost‐Based Selection (QCBS), as this would promote improved Technical Proposals, hence an improved quality of construction. The marking schemes for Technical Proposals must be clearly defined and give traceable results to prevent subjective decision‐making.
The development and implementation of a tunnel characterization method
Authors: Coffman Richard A. , Garner Cyrus D. , Salazar Sean E. 
Published: April 2014

AbstractThe Garner and Coffman method was developed to design a proposed underground facility based on an allowable settlement profile; the method may also be used to characterize an unknown underground facility based on an observed surface settlement profile. The method uses both static methods and 2‐D finite element analyses to relate the characteristics of the ground surface settlement profile to the underground facility (depth, diameter, and number of tunnels). The calibration and validation of the Garner and Coffman method, as obtained by using tunnel segment data from historical tunneling projects (Bangkok, London, Taipei, Singapore, and Heinenoord), are presented. Specifically, the method was calibrated using settlement profiles and facility characteristics from 15 tunnel segments and validated using settlement profiles from 16 additional tunnel segments. A numerical relationship (developed during this research project) was then used during the validation of the model to predict facility characteristics for the “unknown” underground structures. The predicted depth and diameter for each of the “unknown” underground structures were within ten percent of the actual diameter and actual depth of the underground structure, as obtained from the literature. For all 16 validation tunnel segments, the tunnel location was predicted within one tunnel diameter of the actual facility centerline.
The effect of word imagery on priming effect under a preconscious condition: An fMRI study
Authors: Lee Jong‐Sun , Choi Jeewook , Yoo Jae Hyun , Kim Minjung , Lee Seungbok , Kim Ji‐Woong , Jeong Bumseok 
Published: April 2014

AbstractSemantic priming is affected by the degree of association and how readily a word is imagined. In the association effect, activity in the perisylvian structures including the bilateral inferior frontal gyrus, the left middle temporal gyrus, and the supramarginal gyrus was correlated. However, little is known about the brain regions related to the effect of imagery word under the preconscious condition. Forty word pairs for high (HA)‐, low (LA)‐, and nonassociation (NA), nonword (NW) conditions were presented. Each 40 association word pairs (HA and LA) included 20 high (HI) and 20 low (LI) imagery prime stimuli, using a visually presented lexical decision task. A trial consisted of 30 ms prime, 30 ms mask, 500 ms probe, and 2–8 s stimulus onset asynchrony. Brain activation was measured using functional magnetic resonance imaging during word discrimination. Behavioral data indicated that the shortest response time (RT) was given for HA words, followed by LA and NA, and NW showed the longest RT (P < 0.01). RT was faster in HI than LI within HA, but not LA conditions (P < 0.01). Functional neuroimaging showed that differential brain regions for high imagery (HI) and low imagery (LI) words within low prime‐target word association were observed in the left precuneus, left posterior cingulate gyrus, and right cuneal cortex. The present findings demonstrate that the effect of the degree of imagery on semantic priming occurs during the early stage of language processing, indicating an “automatic imagery priming effect.” Our paradigm may be useful to explore semantic deficit related to imagery in various psychiatric disorders. Hum Brain Mapp 35:4795–4804, 2014. © 2014 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc.