bluuebunny/crossref_metadata_2025 huggingface dataset:
The Direct Conversion of Sugars into 2,5‐Furandicarboxylic Acid in a Triphasic System
Authors: Yi Guangshun , Teong Siew Ping , Zhang Yugen
Published: March 2015

A one‐pot conversion of sugars into 2,5‐furandicarboxylic acid (FDCA) is demonstrated in a triphasic system: tetraethylammonium bromide (TEAB) or water—methyl isobutyl ketone (MIBK)—water. In this reaction, sugars are first converted into 5‐hydroxymethylfurfural (HMF) in TEAB or water (Phase I). The HMF in Phase I is then extracted to MIBK (Phase II) and transferred to water (Phase III), where HMF is converted into FDCA. Phase II plays multiple roles: as a bridge for HMF extraction, transportation and purification. Overall FDCA yields of 78 % and 50 % are achieved from fructose and glucose respectively.
Peak‐to‐average power ratio reduction of orthogonal frequency division multiplexing systems using modified tone reservation techniques
Authors: Liang Hsinying , Chu Hung‐Chi , Lin Chuan‐Bi
Published: March 2015

This paper proposed a modified tone reservation (TR) technique that can reduce the peak‐to‐average power ratio (PAPR) of the orthogonal frequency division multiplexing (OFDM) system and is able to correct errors to avoid channel interference. The TR technique is a widely used PAPR reduction technique, which divides subcarriers of the OFDM system into two sets to generate peak‐canceling signals and transmit modulated data. The subcarriers used to reduce the PAPR are called the peak reduction tone sets. The mechanism of peak‐canceling signal generation is a primary factor in determining the quality of the PAPR reduction performance of the TR technique. Currently, two signal generation mechanisms exist: TR‐gradient‐based and TR‐clipping‐based techniques. Although TR techniques can effectively reduce the high PAPR in the OFDM system, TR techniques lack the ability to correct errors. Therefore, this paper combined block coded modulation codes and TR techniques to provide the modified TR techniques with error correction abilities. From the simulation results, the modified TR techniques had a superior effect on PAPR reduction performance compared with the conventional TR technique. The modified TR technique also possessed the ability to correct errors during signal transmission. Copyright © 2015 John Wiley & Sons, Ltd.
A gravitational search algorithm for solving the relay node placement problem in wireless sensor networks
Authors: Lanza‐Gutierrez Jose M. , Gomez‐Pulido Juan A.
Published: March 2015

Nowadays, the use of wireless sensor networks (WSNs) is increasing in many fields of application, such as industrial monitoring, home automation, and intensive agriculture. However, this technology presents an important shortcoming, which has not been solved yet: the energy efficiency. This factor involves a critical economic disadvantage, affecting quality of service. This situation led us to tackle the relay node placement problem, that is, the addition of relay nodes to traditional WSNs as a way to optimize such networks, assuming two important factors: energy consumption and average coverage. To achieve this goal, three multi‐objective (MO) evolutionary algorithms are considered (non‐dominated sorting genetic algoritm II, strength Pareto evolutionary algorithm 2, and MO gravitational search algorithm), assuming a freely available data set and different stop criteria to analyze the behavior of the algorithms. All the results obtained are studied through a widely accepted statistical methodology and two MO metrics (hypervolume and set coverage), concluding that the novel swarm intelligence algorithm MO gravitational search algorithm provides the best performance on average. Moreover, we study the advantages provided by the addition of relay nodes to traditional WSNs. Finally, we compare our proposal with another author approach, assuming a heuristic. Copyright © 2015 John Wiley & Sons, Ltd.
Reconceptualizing synergism and antagonism among multiple stressors
Authors: Piggott Jeremy J. , Townsend Colin R. , Matthaei Christoph D.
Published: March 2015

The potential for complex synergistic or antagonistic interactions between multiple stressors presents one of the largest uncertainties when predicting ecological change but, despite common use of the terms in the scientific literature, a consensus on their operational definition is still lacking. The identification of synergism or antagonism is generally straightforward when stressors operate in the same direction, but if individual stressor effects oppose each other, the definition of synergism is paradoxical because what is synergistic to one stressor's effect direction is antagonistic to the others. In their highly cited meta‐analysis, Crain et al. (Ecology Letters, 11, 2008: 1304) assumed in situations with opposing individual effects that synergy only occurs when the cumulative effect is more negative than the additive sum of the opposing individual effects. We argue against this and propose a new systematic classification based on an additive effects model that combines the magnitude and response direction of the cumulative effect and the interaction effect. A new class of “mitigating synergism” is identified, where cumulative effects are reversed and enhanced. We applied our directional classification to the dataset compiled by Crain et al. (Ecology Letters, 11, 2008: 1304) to determine the prevalence of synergistic, antagonistic, and additive interactions. Compared to their original analysis, we report differences in the representation of interaction classes by interaction type and we document examples of mitigating synergism, highlighting the importance of incorporating individual stressor effect directions in the determination of synergisms and antagonisms. This is particularly pertinent given a general bias in ecology toward investigating and reporting adverse multiple stressor effects (double negative). We emphasize the need for reconsideration by the ecological community of the interpretation of synergism and antagonism in situations where individual stressor effects oppose each other or where cumulative effects are reversed and enhanced.
Dendritic cell regulation of NK‐cell responses involves lymphotoxin‐α, IL‐12, and TGF‐β
Authors: Sarhan Dhifaf , Palma Marzia , Mao Yumeng , Adamson Lars , Kiessling Rolf , Mellstedt Håkan , Österborg Anders , Lundqvist Andreas
Published: March 2015

Dendritic cell (DC) vaccines induce T‐cell responses in cancer patients. However, there is a paucity of data regarding the role of DC vaccines in shaping natural killer (NK) cell responses. Here, we observe that NK cells are less activated following DC vaccination. In vitro, DC‐mediated inhibition of NK cells did not require cell‐to‐cell contact, but required increased Signal transducer and activator of transcription 3 (STAT3) phosphorylation (pSTAT3) in DCs. When phosphorylation of STAT3 was inhibited in DCs, we found that DCs did not suppress NK cells, and observed an increase in the production of lymphotoxin‐alpha (LTα) and interleukin‐12 (IL‐12) as well as reduced release of transforming growth factor beta (TGF‐β). The addition of recombinant LTα or IL‐12 to the DC‐NK‐cell cocultures restored NK‐cell activity, and neutralization of TGF‐β resulted in elevated production of LTα and IL‐12 from DCs. Compared with LPS, DCs matured with a cocktail of R848, poly I:C, and IFN‐γ showed reduced levels of pSTAT3 and higher levels of LTα and IL‐12 and did not inhibit NK‐cell activity. These results show that LTα, IL‐12, and TGF‐β are involved in the cross‐talk between NK cells and DCs. Our findings have important implications for the development of DC‐based vaccination strategies to potentiate NK‐cell responses in patients with cancer.
Ligation of TLR7 on CD19+CD1dhi B cells suppresses allergic lung inflammation via regulatory T cells
Authors: Khan Adnan R. , Amu Sylvie , Saunders Sean P. , Hams Emily , Blackshields Gordon , Leonard Martin O. , Weaver Casey T. , Sparwasser Tim , Sheils Orla , Fallon Padraic G.
Published: March 2015

B cells have been described as having the capacity to regulate cellular immune responses and suppress inflammatory processes. One such regulatory B‐cell population is defined as IL‐10‐producing CD19+CD1dhi cells. Previous work has identified an expansion of these cells in mice infected with the helminth, Schistosoma mansoni. Here, microarray analysis of CD19+CD1dhi B cells from mice infected with S. mansoni demonstrated significantly increased Tlr7 expression, while CD19+CD1dhi B cells from uninfected mice also demonstrated elevated Tlr7 expression. Using IL‐10 reporter, Il10−/− and Tlr7−/‐ mice, we formally demonstrate that TLR7 ligation of CD19+CD1dhi B cells increases their capacity to produce IL‐10. In a mouse model of allergic lung inflammation, the adoptive transfer of TLR7‐elicited CD19+CD1dhi B cells reduced airway inflammation and associated airway hyperresponsiveness. Using DEREG mice to deplete FoxP3+ T regulatory cells in allergen‐sensitized mice, we show that that TLR7‐elicited CD19+CD1dhi B cells suppress airway hyperresponsiveness via a T regulatory cell dependent mechanism. These studies identify that TLR7 stimulation leads to the expansion of IL‐10‐producing CD19+CD1dhi B cells, which can suppress allergic lung inflammation via T regulatory cells.
‘Wind‐up’ in Parkinson's disease: A functional magnetic resonance imaging study
Authors: Aschermann Z. , Nagy F. , Perlaki G. , Janszky J. , Schwarcz A. , Kovacs N. , Bogner P. , Komoly S. , Orsi G.
Published: March 2015

Background

Parkinson's disease (PD) is a neurodegenerative disorder mainly marked by selective degeneration of dopaminergic neurons that leads to disabling motor and cognitive impairment. This condition is less widely appreciated as a disease associated with a substantial variety of pain syndromes, although the prevalence of pain is relatively high. Repeated painful stimulation of peripheral nerves can cause pain ‘wind‐up’ if the frequency of the stimulation is adequate and specifically stimulates the afferent C‐fibres. We presumed that in case of PD, pain or pain severeness might be frequently caused by the aggravation of the ‘wind‐up’ phenomenon due to any central or peripheral lesions or functional alterations.

Methods

To test for this hypothesis, we compared three groups (patients with left‐ and right‐dominant PD and control subjects) using functional magnetic resonance imaging and thermally induced pain.

Results

Patient showed higher average ‘wind‐up’ scores, compared to the healthy subjects, with lower values on the more affected sides compared to the less affected ones. In group level comparisons, patients had higher activation during ‘wind‐up’ compared to control subjects in two main areas; these were the posterior division of cingulate gyrus and the precuneus cortex. In case of patients, further analyses showed that applied heat pain on the less affected side elicited higher activation in the supramarginal and postcentral gyri.

Conclusions

These differences may arise from the deficiency in the efferent information, as well as the alterations in the central processing. It is highly likely that both processes contribute to this phenomenon simultaneously.
Effects of β2 agonists on post‐thoracotomy pain incidence
Authors: Salvat E. , Schweitzer B. , Massard G. , Meyer N. , de Blay F. , Muller A. , Barrot M.
Published: March 2015

Background

Pre‐clinical research has shown β2‐adrenoceptors to be essential for the antiallodynic action of antidepressant drugs in murine models of neuropathic pain and that sustained treatment with β2‐agonists has an antiallodynic action. Here, we clinically investigated whether chronic β2‐agonist treatments may influence the incidence of post‐thoracotomy chronic pain, defined as pain that recurs or persists along a thoracotomy scar more than 2 months after surgery, either neuropathic or non‐neuropathic.

Methods

We conducted an epidemiological study on patients operated by thoracotomy. Demographic data, medical history and treatments concomitant to the surgery were recorded at a follow‐up visit. Information on perioperative treatments was collected from the anaesthesia records and confirmed by the patients. In patients with pain at the surgery level, post‐thoracotomy chronic pain was assessed by clinical examination and numeric scale. Physical examination and DN4 questionnaire were used to discriminate neuropathic and non‐neuropathic chronic pain at scar level.

Results

One hundred and eighty‐nine patients were included. Eighty‐one patients reported persisting thoracic pain, with neuropathic characteristics in 58 of them (30% of the 189 patients). The most common chronic drugs during the perioperative period were inhaled β2‐agonists (28.6%). The chronic use of β2‐agonists was an independent predictor of thoracic neuropathic pain (but not of non‐neuropathic pain) and was associated with a five‐fold decrease in the relative incidence of neuropathic pain [OR = 0.19 (0.06–0.45)].

Conclusions

These data suggest a possible influence of chronic β2‐agonist treatments on neuropathic pain secondary to thoracotomy. This apparent preventive effect of β2‐agonist treatments should warrant controlled clinical trials.
Hydrogen Evolution: Electrochemical Pretreatment for Voltammetric Analysis with Gold Electrodes
Authors: Lamas‐Ardisana Pedro José , Fanjul‐Bolado Pablo , Costa‐García Agustín
Published: March 2015

A pretreatment for gold electrodes is presented in this work. The improvement of the voltammetric responses for gold surfaces is achieved applying an adequate cathodic potential in acidic media which results on vigorous evolution of gas hydrogen at the interface between electrode and electrolyte. The effectiveness of this procedure is evidenced for gold wire electrodes by cyclic voltammetry in several redox systems. The pretreatment is also compared with other activation methods for gold electrodes in electroanalytical and electrochemical terms.
Normal Pulse Voltammetry and Steady State Voltammetry of the Square Mechanism at Spherical Microelectrodes
Authors: Molina A. , Laborda E. , Martínez‐Ortiz F. , Gómez‐Gil J. M.
Published: March 2015

A simple analytical solution is presented for the study of the square mechanism in normal pulse and steady state voltammetries at spherical (ultra)microelectrodes. The analytical expression deduced enables the description of a broad range of situations depending on the chemical kinetics and the difference between the half‐wave potentials of the electron transfers. Regarding the chemical kinetics, the electrochemical response is analysed from the limit of slow kinetics, where the thickness of the reaction layer tends to coincide with that of the diffusion layer, up to the limit of very fast kinetics, where the reaction layer vanishes. Finally, the conditions under which the total steady state response is sensitive to the homogeneous kinetics are studied.
A potential role for the midbrain in integrating fat‐free mass determined energy needs: An H215O PET study
Authors: Weise Christopher M. , Thiyyagura Pradeep , Reiman Eric M. , Chen Kewei , Krakoff Jonathan
Published: March 2015

Little is known on how sensing of energy needs is centrally represented, integrated, and translated into the behavioral aspects of energy homeostasis. Fat free mass (FFM) is the major determinant of energy expenditure. We investigated how interindividual variances in FFM relate to neuronal activity in humans. Healthy adults (n = 64, 21F/43M; age 31.3 ± 9.1y; percentage of body fat [PFAT] 25.6 ± 10.7%; BMI 30.4 ± 9) underwent a 36h fast and subsequent H215O positron emission tomographic (PET) measurement of regional cerebral blood flow (rCBF). Multiple variable regression analysis revealed significant associations of FFM with rCBF within the midbrain [including parts of the periaqueductal gray (PAG), ventral tegmental area (VTA), thalamic and hypothalamic regions], the bilateral parahippocampal region, left anterior cingulate, left insular cortex, right cerebellum, and distinct regions within the temporal and occipital cortex. In contrast, no significant associations were found for fat mass (FM). We investigated the potential functional‐anatomical link between FFM and central regulation of food intake by performing a conjunction analysis of FFM and the perceived hunger feelings. This showed a significant overlap within the midbrain PAG. Mediation analysis demonstrated a significant indirect effect of FFM on hunger with PAG rCBF as mediator. Most regions we found to be associated with FFM form part in ascending homeostatic pathways and cortical circuitries implicated in the regulation of basic bodily functions indicating a potential role of these central networks in the integration of FFM determined energy needs. Hum Brain Mapp 36:2406–2415, 2015. © 2015 Wiley Periodicals, Inc.
The Effect of Medicare Eligibility on Spousal Insurance Coverage
Authors: Dillender Marcus , Mulligan Karen
Published: March 2015

A majority of married couples in the USA take advantage of the fact that employers often provide health insurance coverage to spouses. When older spouses become eligible for Medicare, however, many of them can no longer provide their younger spouses with coverage. In this paper, we study how spousal eligibility for Medicare affects the health insurance and health care access of younger spouses. We find that spousal eligibility for Medicare results in younger spouses no longer having employers pay for their insurance and being less likely to have employer‐sponsored coverage. Instead, younger spouses switch to privately purchased coverage, which tends to be worse than what they had before their spouses became eligible for Medicare. We also find suggestive evidence that younger spouses are less likely to use health care services after their older spouses become eligible for Medicare. Copyright © 2015 John Wiley & Sons, Ltd.
Can substituted allenes be highly efficient leaving groups in catalytic processes? A computational investigation
Authors: Kuriakose Nishamol , Vanka Kumar
Published: March 2015

There is considerable interest presently in the chemistry of allenes. The current computational investigation looks into the possibility of using allenes and their derivatives as leaving groups. As it is well known, leaving groups are significant in catalytic processes for generating the active site. A full quantum mechanical study using density functional theory shows that allenes and their derivatives can function as excellent leaving groups. Indeed, the calculations show that they can be several orders of magnitude more effective than existing ligands for this purpose. The modification of second generation Grubbs' catalysts with these ligands suggests that the allene ligand cases that would be most effective are those having electron withdrawing groups, especially those that have the potential for supramolecular interactions between the substituent groups in the free state. © 2015 Wiley Periodicals, Inc.
The Relationship Between Skill Deficits and Disability–A Transdiagnostic Study
Authors: Hofmann Mareike , Fehlinger Tobias , Stenzel Nikola , Rief Winfried
Published: March 2015

Objective

Transdiagnostic skills (e.g., emotion regulation, stress management) and related self‐concepts (e.g., self‐esteem) are associated with the pathogenesis and course of different mental disorders. Evidence suggests that skill deficits coincide with not only specific psychopathology but also psychological strain and disability. So far, studies examining the relevance of several skills for a patient's disability are lacking. The aim of the present study was the combined assessment of 7 skills and self‐concept variables to simultaneously analyze their relevance for disability.

Method

We interviewed inpatients (N = 183) both on admission and discharge to assess 7 specific skills, 7 areas of daily living disability, and psychopathological distress.

Results

Results support a relationship between several skills and disability (especially stress management), even while controlling for psychopathology. The improvement of skills and related self‐concepts during therapy contributed substantially to the improvement of disability ratings.

Conclusion

This study highlights the transdiagnostic importance of skills as well as the improvement of skills and related self‐concepts as major determinants of disability. Parts of these effects are robust, even while controlling for psychopathology.
ψ‐Hyperholomorphic functions and a Kolosov–Muskhelishvili formula
Authors: Bock S. , Gürlebeck K. , Legatiuk D. , Nguyen H. M.
Published: March 2015

Holomorphic function theory is an effective tool for solving linear elasticity problems in the complex plane. The displacement and stress field are represented in terms of holomorphic functions, well known as Kolosov–Muskhelishvili formulae. In
, similar formulae were already developed in recent papers, using quaternionic monogenic functions as a generalization of holomorphic functions. However, the existing representations use functions from
to
, embedded in
. It is not completely appropriate for applications in
. In particular, one has to remove many redundancies while constructing basis solutions. To overcome that problem, we propose an alternative Kolosov–Muskhelishvili formula for the displacement field by means of a (paravector‐valued) monogenic, an anti‐monogenic and a ψ‐hyperholomorphic function. Copyright © 2015 John Wiley & Sons, Ltd.
A posteriorierror estimates of stabilized finite volume method for the Stokes equations
Authors: Zhang Tong , Mu Lin , Yuan JinYun
Published: March 2015

In this work, the residual‐type posteriori error estimates of stabilized finite volume method are studied for the steady Stokes problem based on two local Gauss integrations. By using the residuals between the source term and numerical solutions, the computable global upper and local lower bounds for the errors of velocity inH1norm and pressure inL2norm are derived. Furthermore, a global upper bound ofu−uhinL2‐norm is also derived. Finally, some numerical experiments are provided to verify the performances of the established error estimators. Copyright © 2015 John Wiley & Sons, Ltd.
Quantitative framework for prospective motion correction evaluation
Authors: Pannetier Nicolas A. , Stavrinos Theano , Ng Peter , Herbst Michael , Zaitsev Maxim , Young Karl , Matson Gerald , Schuff Norbert
Published: March 2015

Purpose

Establishing a framework to evaluate performances of prospective motion correction (PMC) MRI considering motion variability between MRI scans.

Methods

A framework was developed to obtain quantitative comparisons between different motion correction setups, considering that varying intrinsic motion patterns between acquisitions can induce bias. Intrinsic motion was considered by replaying in a phantom experiment the recorded motion trajectories from subjects. T1‐weighted MRI on five volunteers and two different marker fixations (mouth guard and nose bridge fixations) were used to test the framework. Two metrics were investigated to quantify the improvement of the image quality with PMC.

Results

Motion patterns vary between subjects as well as between repeated scans within a subject. This variability can be approximated by replaying the motion in a distinct phantom experiment and used as a covariate in models comparing motion corrections. We show that considering the intrinsic motion alters the statistical significance in comparing marker fixations. As an example, two marker fixations, a mouth guard and a nose bridge, were evaluated in terms of their effectiveness for PMC. A mouth guard achieved better PMC performance.

Conclusion

Intrinsic motion patterns can bias comparisons between PMC configurations and must be considered for robust evaluations. A framework for evaluating intrinsic motion patterns in PMC is presented. Magn Reson Med 75:810–816, 2016. © 2015 Wiley Periodicals, Inc.
Investigating the dependence of the calibration parameter M on echo time
Authors: Hare Hannah V. , Bulte Daniel P.
Published: March 2015

Purpose

The calculation of the calibration parameter M, which represents the maximum theoretically possible blood oxygen level dependent (BOLD) signal increase, is an essential intermediate step in any calibrated fMRI experiment. To better compare M values obtained across different studies, it is common to scale M values from their original BOLD echo time (TE) to a different echo time according to the theory that M is directly proportional to TE. To the best of our knowledge, this relationship has never been directly tested.

Theory and Methods

A pseudocontinuous arterial spin labeling sequence with five readouts (TE ranging from 20 to 78 ms) was implemented to test the relationship between M and TE, both with and without the application of flow crushing gradients.

Results

Both M and the BOLD signal were found to be linear functions of TE, but with a nonzero intercept. This intercept was reduced when crusher gradients were added, suggesting that the deviation from theory is a result of nonnegligible intravascular signal.

Conclusion

The linear scaling method introduces some error when comparing M values acquired with different BOLD echo times. However, this error is small compared with other considerations, and would generally not preclude the continued use of this scaling method. Magn Reson Med 75:556–561, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.
Clinical applications at ultrahigh field (7  T). Where does it make the difference?
Authors: Trattnig Siegfried , Bogner Wolfgang , Gruber Stephan , Szomolanyi Pavol , Juras Vladimir , Robinson Simon , Zbýň Štefan , Haneder Stefan
Published: March 2015

Presently, three major MR vendors provide commercial 7‐T units for clinical research under ethical permission, with the number of operating 7‐T systems having increased to over 50. This rapid increase indicates the growing interest in ultrahigh‐field MRI because of improved clinical results with regard to morphological as well as functional and metabolic capabilities. As the signal‐to‐noise ratio scales linearly with the field strength (B0) of the scanner, the most obvious application at 7 T is to obtain higher spatial resolution in the brain, musculoskeletal system and breast. Of specific clinical interest for neuro‐applications is the cerebral cortex at 7 T, for the detection of changes in cortical structure as a sign of early dementia, as well as for the visualization of cortical microinfarcts and cortical plaques in multiple sclerosis. In the imaging of the hippocampus, even subfields of the internal hippocampal anatomy and pathology can be visualized with excellent resolution. The dynamic and static blood oxygenation level‐dependent contrast increases linearly with the field strength, which significantly improves the pre‐surgical evaluation of eloquent areas before tumor removal. Using susceptibility‐weighted imaging, the plaque–vessel relationship and iron accumulation in multiple sclerosis can be visualized for the first time. Multi‐nuclear clinical applications, such as sodium imaging for the evaluation of repair tissue quality after cartilage transplantation and 31P spectroscopy for the differentiation between non‐alcoholic benign liver disease and potentially progressive steatohepatitis, are only possible at ultrahigh fields. Although neuro‐ and musculoskeletal imaging have already demonstrated the clinical superiority of ultrahigh fields, whole‐body clinical applications at 7 T are still limited, mainly because of the lack of suitable coils. The purpose of this article was therefore to review the clinical studies that have been performed thus far at 7 T, compared with 3 T, as well as those studies performed at 7 T that cannot be routinely performed at 3 T. Copyright © 2015 John Wiley & Sons, Ltd.
Correlating high‐resolution magic angle spinning NMR spectroscopy and gene analysis in osteoarthritic cartilage
Authors: Tufts Lauren , Shet Vishnudas Keerthi , Fu Eunice , Kurhanewicz John , Ries Michael , Alliston Tamara , Li Xiaojuan
Published: March 2015

Osteoarthritis (OA) is a common multifactorial and heterogeneous degenerative joint disease, and biochemical changes in cartilage matrix occur during the early stages of OA before morphological changes occur. Thus, it is desired to measure regional biochemical changes in the joint. High‐resolution magic angle spinning (HRMAS) NMR spectroscopy is a powerful method of observing cartilaginous biochemical changes ex vivo, including the concentrations of alanine and N‐acetyl, which are markers of collagen and total proteoglycan content, respectively. Previous studies have observed significant changes in chondrocyte metabolism of OA cartilage via the altered gene expression profiles of ACAN, COL2A1 and MMP13, which encode aggrecan, type II collagen and matrix metalloproteinase 13 (a protein crucial in the degradation of type II collagen), respectively. Employing HRMAS, this study aimed to elucidate potential relationships between N‐acetyl and/or alanine and ACAN, COL2A1 and/or MMP13 expression profiles in OA cartilage. Thirty samples from the condyles of five subjects undergoing total knee arthroplasty to treat OA were collected. HRMAS spectra were obtained at 11.7 T for each sample. RNA was subsequently extracted to determine gene expression profiles. A significant negative correlation between N‐acetyl metabolite and ACAN gene expression levels was observed; this provides further evidence of N‐acetyl as a biomarker of cartilage degeneration. The alanine doublet was distinguished in the spectra of 15 of the 30 specimens of this study. Alanine can only be detected with HRMAS NMR spectroscopy when the collagen framework has been degraded such that alanine is sufficiently mobile to form a distinguished peak in the spectrum. Thus, HRMAS NMR spectroscopy may provide unique localized measurements of collagenous degeneration in OA cartilage. The identification of imaging markers that could provide a link between OA pathology and chondrocyte metabolism will facilitate the development of more sensitive diagnostic techniques and will improve methods of monitoring treatment for patients suffering from OA. Copyright © 2015 John Wiley & Sons, Ltd.
On the use of suboptimal matchings for scaling and ordering sparse symmetric matrices
Authors: Hogg Jonathan , Scott Jennifer
Published: March 2015

The use of matchings is a powerful technique for scaling and ordering sparse matrices prior to the solution of a linear systemAx=b. Traditional methods such as implemented by theHSLsoftware packageMC64use the Hungarian algorithm to solve the maximum weight maximum cardinality matching problem. However, with advances in the algorithms and hardware used by direct methods for the parallelization of the factorization and solve phases, the serial Hungarian algorithm can represent an unacceptably large proportion of the total solution time for such solvers. Recently, auction algorithms and approximation algorithms have been suggested as alternatives for achieving near‐optimal solutions for the maximum weight maximum cardinality matching problem. In this paper, the efficacy of auction and approximation algorithms as replacements for the Hungarian algorithm is assessed in the context of sparse symmetric direct solvers when used in problems arising from a range of practical applications. High‐cardinality suboptimal matchings are shown to be as effective as optimal matchings for the purposes of scaling. However, matching‐based ordering techniques require that matchings are much closer to optimality before they become effective. The auction algorithm is demonstrated to be capable of finding such matchings significantly faster than the Hungarian algorithm, but our‐approximation matching approach fails to consistently achieve a sufficient cardinality. Copyright © 2015 The Authors Numerical Linear Algebra with Applications Published by John Wiley & Sons Ltd.
A fractional rate‐dependent cohesive‐zone model
Authors: Musto Marco , Alfano Giulio
Published: March 2015

This paper presents a novel formulation of a hereditary cohesive zone model able to effectively capture rate‐dependent crack propagation along a defined interface, over a wide range of applied loading rates and with a single set of seven input parameters only, as testified by the remarkable agreement with experimental results in the case of a double cantilever beam made of steel adherends bonded along a rubber interface. The formulation relies on the assumption that the measured fracture energy is the sum of a rate‐independent ‘rupture’ energy, related to the rupture of primary bonds at the atomic or molecular level, and of additional dissipation caused by other rate‐dependent dissipative mechanisms present in the material and occurring simultaneously to rupture. The first contribution is accounted for by introducing a damage‐type internal variable, whose evolution follows a rate‐independent law for consistency with the assumption of rate independence of the rupture energy. To account for the additional dissipation, a fractional‐calculus‐based linear viscoelastic model is used, because for many polymers, it is known to capture the material response within an extremely wide range of strain rates much more effectively than classic models based on an exponential kernel. To the authors' knowledge, this is the first application of fractional viscoelasticity to the simulation of fracture. © 2015 The Authors. International Journal for Numerical Methods in Engineering published by John Wiley & Sons Ltd.
Effects of poly(ethylene glycol) grafted silica nanoparticles on crystallization behavior of poly(d‐lactide)
Authors: Wang Zuoning , Xia Shuang , Chen Hong , Wang Song , Nie Kangming , Li Zhibo
Published: March 2015

A series of biodegradable poly(d‐lactide) (PDLA) nanocomposites filled with silica nanoparticles with different surface characteristics were prepared via the solvent casting method. The crystallization behavior of PDLA was investigated at different temperatures. For these hybrid nanocomposites, the effects of silica nanoparticles displayed distinct influences on the crystallization behavior of PDLA depending on the temperature. Bare silica nanoparticles increased the crystallization behavior of PDLA regardless of annealing temperature. In contrast, poly(ethylene glycol) (PEG) grafted silica nanoparticles increased the crystallization rate at 80 and 130 °C, but they decreased the crystallization rate at 120 °C. A possible reason was that PEG grafted silica nanoparticles acted as plasticizers while the bare silica nanoparticles acted as nucleating agents. © 2015 Society of Chemical Industry
Temporal SILAC‐based quantitative proteomics identifies host factors involved in chikungunya virus replication
Authors: Treffers Emmely E. , Tas Ali , Scholte Florine E.M. , Van Myrthe N. , Heemskerk Matthias T. , de Ru Arnoud H. , Snijder Eric J. , van Hemert Martijn J. , van Veelen Peter A.
Published: March 2015

Chikungunya virus (CHIKV) is an arthropod‐borne reemerging human pathogen that generally causes a severe persisting arthritis. Since 2005, the virus has infected millions of people during outbreaks in Africa, Indian Ocean Islands, Asia, and South/Central America. Many steps of the replication and expression of CHIKV's 12‐kb RNA genome are highly dependent on cellular factors, which thus constitute potential therapeutic targets. SILAC and LC‐MS/MS were used to define the temporal dynamics of the cellular response to infection. Using samples harvested at 8, 10, and 12 h postinfection, over 4700 proteins were identified and per time point 2800–3500 proteins could be quantified in both biological replicates. At 8, 10, and 12 h postinfection, 13, 38, and 106 proteins, respectively, were differentially expressed. The majority of these proteins showed decreased abundance. Most subunits of the RNA polymerase II complex were progressively degraded, which likely contributes to the transcriptional host shut‐off observed during CHIKV infection. Overexpression of four proteins that were significantly downregulated (Rho family GTPase 3 (Rnd3), DEAD box helicase 56 (DDX56), polo‐like kinase 1 (Plk1), and ubiquitin‐conjugating enzyme E2C (UbcH10) reduced susceptibility of cells to CHIKV infection, suggesting that infection‐induced downregulation of these proteins is beneficial for CHIKV replication. All MS data have been deposited in the ProteomeXchange with identifier PXD001330 (http://proteomecentral.proteomexchange.org/dataset/PXD001330).
Plasma Thorns: Atmospheric Pressure Non‐Thermal Plasma Source for Dentistry Applications
Authors: Liang Yongdong , Li Yinglong , Sun Ke , Zhang Qian , Li Wei , Zhu Weidong , Zhang Jue , Fang Jing
Published: March 2015

A novel atmospheric pressure, non‐thermal plasma source – plasma thorns, can simultaneously generate plasma plumes toward multiple preset directions. This plasma source is proposed here for the sterilization of the inner surfaces of tubular structures. Compared with the highly directional plasma jets or jet arrays, the plasma thorns provides significantly higher antimicrobial efficacy in the radial directions. After treatment with plasma thorns of the root canal biofilm, a significant decrease in the number of CFUs was observed. It is possible to reduce the size of the device to even micrometer scale, which opens doors to many potential applications, such as the treatment of multiple internal cavities or complex hollow structures.
Protein structural dynamics at the gas/water interface examined by hydrogen exchange mass spectrometry
Authors: Xiao Yiming , Konermann Lars
Published: March 2015

Gas/water interfaces (such as air bubbles or foam) are detrimental to the stability of proteins, often causing aggregation. This represents a potential problem for industrial processes, for example, the production and handling of protein drugs. Proteins possess surfactant‐like properties, resulting in a high affinity for gas/water interfaces. The tendency of previously buried nonpolar residues to maximize contact with the gas phase can cause significant structural distortion. Most earlier studies in this area employed spectroscopic tools that could only provide limited information. Here we use hydrogen/deuterium exchange (HDX) mass spectrometry (MS) for probing the conformational dynamics of the model protein myoglobin (Mb) in the presence of N2 bubbles. HDX/MS relies on the principle that unfolded and/or highly dynamic regions undergo faster deuteration than tightly folded segments. In bubble‐free solution Mb displays EX2 behavior, reflecting the occurrence of short‐lived excursions to partially unfolded conformers. A dramatically different behavior is seen in the presence of N2 bubbles; EX2 dynamics still take place, but in addition the protein shows EX1 behavior. The latter results from interconversion of the native state with conformers that are globally unfolded and long‐lived. These unfolded species likely correspond to Mb that is adsorbed to the surface of gas bubbles. N2 sparging also induces aggregation. To explain the observed behavior we propose a simple model, that is, “semi‐unfolded” ↔ “native” ↔ “globally unfolded” → “aggregated”. This model quantitatively reproduces the experimentally observed kinetics. To the best of our knowledge, the current study marks the first exploration of surface denaturation phenomena by HDX/MS.
The efficiency challenge of nitride light‐emitting diodes for lighting
Authors: Weisbuch Claude , Piccardo Marco , Martinelli Lucio , Iveland Justin , Peretti Jacques , Speck James S.
Published: March 2015

We discuss the challenges of light‐emitting diodes in view of their application to solid‐state lighting. The requirement is to at least displace the quite efficient fluorescent, sodium, and high intensity discharge lamps used today in the main energy consuming lighting sectors, industrial, commercial and outdoors, with more efficient and better light quality lamps. We show that both from the point of view of cost of ownership and carbon emissions reduction, the relevant metric is efficiency, more than the cost of lumens. Then, progress from present performance requires identification of the loss mechanisms in light emission from LEDs, and solutions competing with mainstream c‐plane LEDS grown on sapphire need to be on par with these. Special attention is devoted to a discussion of the efficiency droop mechanisms, and of a recent direct measurement of Auger generated electrons which appear to be responsible for droop.
Optoelectronic characteristics of >9% efficient bilayered CuZnSn(S,Se)4 photovoltaic device
Authors: Wu Wei , Tassi Nancy G. , Cao Yanyan , Caspar Jonathan V. , Roy‐Choudhury Kaushik , Zhang Lei
Published: March 2015

Using binary and ternary chalcogenide nanoparticle solutions as precursors, a bi‐layered CZTSSe film is formed after being annealed in selenium atmosphere. Based on the CZTSSe film, a high efficiency thin‐film photovoltaic device (9.02% conversion efficiency) is made. Detailed characterizations of the device's performance and composition from XPS depth profiling are presented, and based on the results we discuss possible areas for further efficiency improvement. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
Computing Transition Probability in Markov Chain for Early Prediction of Software Reliability
Authors: Singh Lalit , Rajput Hitesh , Vinod Gopika , Tripathi A. K.
Published: March 2015

Early prediction of software reliability provides basis for evaluating potential reliability during early stages of a project. It also assists in evaluating the feasibility of proposed reliability requirements and provides a rational basis for design and allocation decisions. Many researchers have proposed different approaches to predict the software reliability based on a Markov model. The transition probabilities in between the states of the Markov model are input parameters to predict the software reliability. In the existing approaches, these probabilities are either assumed on some knowledge or computed using analytical method, and hence, it does not give accurate predicted reliability figure. Some authors compute them using operational profile data, but that is possible only after the deployment of the software, and this is not early prediction. The work in this paper is devoted to demonstrate the computation of transition probability in the Markov reliability model taking a case study. The proposed approach has been validated on 47 sets of real data. Copyright © 2015 John Wiley & Sons, Ltd.
The selective dopamine D3 receptor antagonist SB‐277011‐A significantly decreases binge‐like consumption of ethanol in C57BL/J6 mice
Authors: Rice Onarae V. , Schonhar Charles A. , Gaál J. , Gardner Eliot L. , Ashby Charles R.
Published: March 2015

The authors show that the dopamine D3 antagonist SB‐277011‐A consistently and persistently decrease binge‐like EtOH consumption at 30 mg/kg and it decreases binge‐like consumption on days 3, 7, 9, and 11–13 at 15 mg/kg. These findings suggest that the brain's D3 receptor may also be involved in not only ethanol reward but binge drinking as well. Synapse 69:295–298, 2015. © 2015 Wiley Periodicals, Inc.
Economic Evaluation of Flexibility in the Design of IGCC Plants with Integrated Membrane Reactor Modules
Authors: Zhang Juzheng , Cardin Michel‐Alexandre , Kazantzis Nikolaos , Ng Simon K. K. , Ma Y. H.
Published: March 2015

Integrated Gasification Combined Cycle with embedded membrane reactor modules (IGCC‐MR) represents a new technology option for the coproduction of electricity and pure hydrogen endowed with enhanced environmental performance capacity. It is viewed as an alternative to conventional coal‐ and gas‐fired power generation technologies. An IGCC‐MR power plant needs to be techno‐economically evaluated in the presence of irreducible regulatory and fuel market uncertainties for the potential deployment of an initial fleet of demonstration plants at the commercial scale. This paper applies a systematic methodological framework to assess the economic value of flexible alternatives in the design and operation of an IGCC‐MR plant under the aforementioned sources of uncertainty. The main objective is to demonstrate the potential value enhancements associated with the long‐term economic performance of flexible IGCC‐MR project investments, by managing the uncertainty associated with future environmental regulations and fuel costs. The paper provides an overview of promising design flexibility concepts for IGCC‐MR power plants and focuses on operational and constructional systems flexibility. Operational flexibility is realized through temporary plant shutdown with considerations of regulatory and market uncertainties. Constructional flexibility is realized by considering the installation of a Carbon Capture and Storage (CCS) unit at three strategic periods: (1) installation at the initial construction phase, (2) retrofitting at a later stage, and (3) retrofitting at a later stage with preinvestment. Monte Carlo simulations and financial analysis demonstrate that, in the presence of irreducible uncertainty, the most economically advantageous flexibility option is to install CCS in the initial IGCC‐MR construction phase.
Hydrologic ecosystem services: linking ecohydrologic processes to human well‐being in water research and watershed management
Authors: Brauman Kate A.
Published: March 2015

Ecosystem services, the benefits ecosystems provide to people, and hydrologic services, the subset of terrestrial ecosystem services related to water, appear with increasing frequency in water resources research and watershed management. Linking biophysical function to human well‐being is central to the theory of ecosystem services, so distinctive characteristics of research on hydrologic services arise from addressing the way people are affected by ecohydrologic processes. However, based on a rapid scoping of 381 peer‐reviewed studies of hydrologic services, I identified only a small fraction that appear to effectively make the link from biophysical processes to people. In their abstracts, many of the reviewed articles use the language of hydrologic services but appear to be essentially disciplinary studies, accounting for either biophysical functioning or specific beneficiaries in their analysis, but not both. In addition to guiding research, the direct link from biophysical processes to human well‐being makes hydrologic services an appealing foundation for watershed management. The hydrologic services framework has been used to assess conservation benefits, evaluate management practices, prioritize siting, account for externalities, and perform trade‐off or cost‐benefit analysis. Hydrologic services hold potential for novel research and effective watershed management, but challenges remain in executing interdisciplinary research and in addressing the idiosyncratic demands of local management. WIREs Water 2015, 2:345–358. doi: 10.1002/wat2.1081

This article is categorized under:

Water and Life > Conservation, Management, and Awareness

Science of Water > Hydrological Processes

Human Water > Value of Water