bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrochemiluminescence Sensor for Phosphate Ions Based on Europium(III)‐Modulated CdSe Quantum Dots
Authors: Li Qi‐Le , Bao Ning , Ding Shou‐Nian 
Published: October 2014

AbstractPhosphate anions are determined based on the electrochemiluminescence (ECL) of CdSe quantum dots (CdSe QDs) capped with 3‐mercaptopropionic acid. The ECL gets quenched with the introduction of Eu3+ ions, but it is restored on the further addition of phosphate anions. The sensing mechanism might be due to the strong and specific interaction between phosphate anions and the Eu3+ ions, leading to the releasing of CdSe QDs from aggregates. On the basis of the quenching/recovery ECL behaviors, the ECL sensor offer acceptable sensitivity, high selectivity, and a linear response from 0.1 to 120 µM with a detection limit of 0.03 µM (3δ) for phosphate anions.
Simple DPPH.‐Based Electrochemical Assay for the Evaluation of the Antioxidant Capacity: a Thorough Comparison with Spectrophotometric Assays and Evaluation with Real‐World Samples
Authors: Andrei Veronica , Bunea Ada‐Ioana , Tudorache Aurelia , Gáspár Szilveszter , Vasilescu Alina 
Published: October 2014

AbstractAn assay based on the electrochemical detection of 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH.) for the evaluation of the total antioxidant capacity (TAC) was optimized. The assay is interchangeable with the classic spectrophotometric tests for TAC based on the same radical. In addition, it can be used for the analysis of dilute samples with low antioxidant capacities. A good linear correlation (R2=0.97) was obtained between the results obtained with the proposed electrochemical assay and the Trolox Equivalent Antioxidant Capacity test based on ABTS radical. The assay was successfully used to evaluate the antioxidant capacity of two red wines obtained by six different maceration‐fermentation techniques.
A Simple Econometric Approach for Modeling Stress Event Intensities
Authors: Jobst Rainer , Rösch Daniel , Scheule Harald , Schmelzle Martin 
Published: October 2014

AbstractThis paper introduces a simple, non‐parametric way of inferring risk‐neutral credit stress event intensities for idiosyncratic, sectoral, and global shocks contained in market credit spreads. We provide an econometric analysis of the implied latent stress event dynamics. A vector autoregressive regression model with exogenous variables finds that these intensities can be related to an observable stock market index, the market volatility, the volatility skew, and treasury yields. © 2014 Wiley Periodicals, Inc. Jrl Fut Mark 35:300–320, 2015
Validation of the Montreal Cognitive Assessment (MoCA) in Spanish as a screening tool for mild cognitive impairment and mild dementia in patients over 65 years old in Bogotá, Colombia
Authors: Gil Laura , Ruiz de Sánchez Carolina , Gil Fabián , Romero Sara Julieta , Pretelt Burgos Felipe 
Published: October 2014

ObjectiveThe Montreal Cognitive Assessment (MoCA) was developed as a simple screening tool for cognitive impairment. This study is the first validation in Latin America of the MoCA in Spanish (MoCA‐S), which was developed in Colombia (South America).MethodsAiming to perform the first validation of the MoCA‐S, we developed a study of concordance by conformity to assess the MoCA‐S compared with diagnostic consensus by interdisciplinary assessment in the Memory Clinic (the best diagnostic method available) and to evaluate the psychometric properties of the MoCA‐S. A total of 193 subjects were evaluated, 109 of whom were patients, including 26 who met the mild cognitive impairment (MCI) clinical criteria, based on neuropsychological testing, and 83 who had mild dementia (MD). The remaining 84 participants were healthy subjects from the community.ResultsThe psychometric evaluation of the MoCA‐S was appropriate. Using a cutoff score of ≥23, the MoCA had sensitivities of 76.0% to detect MCI and 92.7% to detect MD and a specificity of 79.8%. The percentage of patients clearly labeled by the MoCA‐S was 85%.ConclusionThe MoCA‐S is a valid screening tool and is useful for identifying MCI and MD in Colombia. The MoCA‐S is valid and adequate for application in Colombia with good internal consistency, inter‐observer reliability, and content validity. However, the average educational level was high in this study; thus, caution should be exercised when extrapolating these results to individuals with lower educational levels. Copyright © 2014 John Wiley & Sons, Ltd.
Brain activation to briefly presented emotional words: Effects of stimulus awareness
Authors: Hoffmann Marius , Mothes‐Lasch Martin , Miltner Wolfgang H.R. , Straube Thomas 
Published: October 2014

AbstractIt is unknown to what extent briefly presented emotional words can be processed without awareness. By means of two independent functional magnetic resonance imaging studies, using either a block or an event‐related design, we investigated brain activation to very briefly presented threat related and neutral words during two backward masking conditions (with and without gap between target and mask). In both experiments, emotional words were perceived during the supraliminal “with gap” condition, but they were not recognized during the subliminal “without gap” condition, as indicated by signal detection theory analysis. Imaging results of both experiments showed increased activation of the amygdala, the medial prefrontal cortex and language‐processing cortical areas to negative versus neutral words during supraliminal but not subliminal conditions. These results suggest that even very briefly presented emotional words are capable of triggering increased cortical and subcortical processing; however, only when awareness of these stimuli is given. Hum Brain Mapp 36:655–665, 2015. © 2014 Wiley Periodicals, Inc.
Acute effect of glucose on cerebral blood flow, blood oxygenation, and oxidative metabolism
Authors: Xu Feng , Liu Peiying , Pascual Juan M , Xiao Guanghua , Huang Hao , Lu Hanzhang 
Published: October 2014

AbstractWhile it is known that specific nuclei of the brain, for example hypothalamus, contain glucose‐sensing neurons thus their activity is affected by blood glucose level, the effect of glucose modulation on whole‐brain metabolism is not completely understood. Several recent reports have elucidated the long‐term impact of caloric restriction on the brain, showing that animals under caloric restriction had enhanced rate of tricarboxylic acid cycle (TCA) cycle flux accompanied by extended life span. However, acute effect of postprandial blood glucose increase has not been addressed in detail, partly due to a scarcity and complexity of measurement techniques. In this study, using a recently developed noninvasive MR technique, we measured dynamic changes in global cerebral metabolic rate of O2 (CMRO2) following a 50 g glucose ingestion (N = 10). A time dependent decrease in CMRO2 was observed, which was accompanied by a reduction in oxygen extraction fraction (OEF) with unaltered cerebral blood flow (CBF). At 40 min post‐ingestion, the amount of CMRO2 reduction was 7.8 ± 1.6%. A control study without glucose ingestion was performed (N = 10), which revealed no changes in CMRO2, CBF, or OEF, suggesting that the observations in the glucose study was not due to subject drowsiness or fatigue after staying inside the scanner. These findings suggest that ingestion of glucose may alter the rate of cerebral metabolism of oxygen in an acute setting. Hum Brain Mapp 36:707–716, 2015. © 2014 Wiley Periodicals, Inc.
Uncertainty during pain anticipation: The adaptive value of preparatory processes
Authors: Seidel Eva‐Maria , Pfabigan Daniela M. , Hahn Andreas , Sladky Ronald , Grahl Arvina , Paul Katharina , Kraus Christoph , Küblböck Martin , Kranz Georg S. , Hummer Allan , Lanzenberger Rupert , Windischberger Christian , Lamm Claus 
Published: October 2014

AbstractObjectives: Anticipatory processes prepare the organism for upcoming experiences. The aim of this study was to investigate neural responses related to anticipation and processing of painful stimuli occurring with different levels of uncertainty. Experimental design: Twenty‐five participants (13 females) took part in an electroencephalography and functional magnetic resonance imaging (fMRI) experiment at separate times. A visual cue announced the occurrence of an electrical painful or nonpainful stimulus, delivered with certainty or uncertainty (50% chance), at some point during the following 15 s. Principal observations: During the first 2 s of the anticipation phase, a strong effect of uncertainty was reflected in a pronounced frontal stimulus‐preceding negativity (SPN) and increased fMRI activation in higher visual processing areas. In the last 2 s before stimulus delivery, we observed stimulus‐specific preparatory processes indicated by a centroparietal SPN and posterior insula activation that was most pronounced for the certain pain condition. Uncertain anticipation was associated with attentional control processes. During stimulation, the results revealed that unexpected painful stimuli produced the strongest activation in the affective pain processing network and a more pronounced offset‐P2. Conclusions: Our results reflect that during early anticipation uncertainty is strongly associated with affective mechanisms and seems to be a more salient event compared to certain anticipation. During the last 2 s before stimulation, attentional control mechanisms are initiated related to the increased salience of uncertainty. Furthermore, stimulus‐specific preparatory mechanisms during certain anticipation also shaped the response to stimulation, underlining the adaptive value of stimulus‐targeted preparatory activity which is less likely when facing an uncertain event. Hum Brain Mapp 36:744–755, 2015. © 2014 Wiley Periodicals, Inc.
RF modeling of 40‐nm SOI triple‐gate FinFET
Authors: Martinez‐Lopez A. G. , Cerdeira A. , Tinoco J. C. , Alvarado J. , Padron W. Y. , Mendoza C. , Raskin J.‐P. 
Published: October 2014

AbstractThese last years, the triple‐gate fin field‐effect transistor (FinFET) has appeared as attractive candidate to pursue the complementary metal‐oxide semiconductor technology roadmap for digital and analog applications. However, the development of analog applications requires models that properly describe the static and RF behaviors as well as the extrinsic parameters related to the three‐dimensional FinFET architecture, in order to establish adequate design strategies. We demonstrate the feasibility of the compact model developed for symmetric doped double‐gate metal‐oxide‐semiconductor field‐effect transistor (symmetric doped double‐gate MOSFET) to reproduce the experimental dc and RF behaviors for 40‐nm technology node Silicon‐on‐Insulator triple‐gate FinFETs. Extrinsic gate capacitances and access extrinsic resistances have been included in order to properly predict the transistor small‐signal behavior, the current gain, and the maximum available power gain cut‐off frequencies. Finally, the improvement of the FinFET RF characteristics by the reduction of the parasitics is addressed. Copyright © 2014 John Wiley & Sons, Ltd.
The Impact of Childhood Abuse Among Women With Assault‐Related PTSD Receiving Short‐Term Cognitive–Behavioral Therapy
Authors: Resick Patricia A. , Suvak Michael K. , Wells Stephanie Y. 
Published: October 2014

AbstractThis study examined the effect of child sexual or physical abuse on brief cognitive–behavioral therapy treatments with adults with posttraumatic stress disorder (PTSD). We analyzed secondary data from two randomized controlled trials (Resick, Nishith, Weaver, Astin, & Feuer, 2002; Resick et al., 2008) that included women with PTSD who did or did not have child sexual abuse (CSA) or child physical abuse (CPA) histories to determine whether childhood abuse impacted dropout rate or reduction in PTSD symptoms. In Study 1, presence, duration, or severity of CSA was not associated with dropout; however, frequency of CSA significantly predicted dropout (OR = 1.23). A significant CPA Severity × Treatment Group interaction emerged such that CPA severity was associated with greater dropout for prolonged exposure (PE; OR = 1.45), but not cognitive processing therapy (CPT; OR = 0.90). Study 2 found no differences in dropout. Study 1, comparing CPT and PE among women who experienced at least 1 rape found no differences in outcome based on childhood abuse history (rp2s = .000–.009). Study 2, a dismantling study of CPT with women seeking treatment for adult or child sexual or physical abuse found that for those with no childhood abuse, CPT‐C, the cognitive‐only version of CPT, had an advantage, whereas both forms of CPT worked best for those with higher frequency of childhood abuse; the effect size was small.
Probable Posttraumatic Stress Disorder and Women's Use of Aggression in Intimate Relationships: The Moderating Role of Alcohol Dependence
Authors: Weiss Nicole H. , Duke Aaron A. , Sullivan Tami P. 
Published: October 2014

AbstractPosttraumatic stress disorder (PTSD) is highly prevalent among individuals who experience intimate partner violence (IPV) and is associated with aggression in intimate relationships. The present study examined whether alcohol dependence (AD) attenuates the relation between PTSD and IPV‐victimized women's use of physical, psychological, and sexual aggression. Participants were recruited from the community and included 147 women who engaged in substance use and experienced IPV (80.3% Black; M age = 38.24 years, SD = 10.62; M income = $14,323, SD = $12,832). Women with (vs. without) AD reported using significantly more physical and psychological aggression (ηp2 = .12 and .03, respectively). The probable PTSD × AD interaction emerged as a significant correlate of physical and sexual aggression (ηp2 = .03). Post hoc analyses revealed higher levels of physical aggression among women with probable PTSD and AD and no‐PTSD and AD compared to women with probable PTSD and no‐AD (Cohen's ds = 1.09 and 0.63, respectively) and women without PTSD and no‐AD (Cohen's ds = 0.92 and 0.60, respectively). Further, women with PTSD and AD reported higher levels of sexual aggression than women without PTSD and AD (Cohen's d = 0.80). Findings suggest the utility of identifying and treating PTSD‐AD among IPV‐victimized women.
Glutathione‐Responsive DNA‐Based Nanocontainers Through an “Interfacial Click” Reaction in Inverse Miniemulsion
Authors: Paiphansiri Umaporn , Baier Grit , Kreyes Andreas , Yiamsawas Doungporn , Koynov Kaloian , Musyanovych Anna , Landfester Katharina 
Published: October 2014

The synthesis of nanoscale biocompatible carriers that are able to release encapsulated material within an intracellular environment in a controlled way still remains a challenge. Hereby, the synthesis of a new class of DNA‐based nanocontainers having a glutathione‐cleavable shell is described. These containers are able to break in response to the presence of intracellular specific tripeptide glutathione in the surrounding medium. The formulation of nanocontainers in the size range between 190 and 220 nm is achieved through the interfacial thiol–disulfide exchange reaction between dithiol DNA oligonucleotides (20 bases) and disulfide groups of a comonomer in inverse miniemulsion. DNA containers with different disulfide moieties are synthesized by taking different ratios of a dimaleimide‐based fluorescent BODIPY dye and the disulfide monomer, which form the shell through the “interfacial click” of the thiol‐ene reaction and the dithiol exchange reaction of the glutathione‐cleavable disulphide comonomer. The disruption kinetics of the shell upon addition of glutathione into the dispersion are investigated by isothermal titration calorimetry (ITC). Cleavage of the nanocontainer's shell containing fluorescent BODIPY dye is confirmed by fluorescence correlation spectroscopy (FCS). It is believed that the obtained nanocontainers have great potential as smart nanocarriers in biosensor and therapeutic applications.
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Inhomogeneous static magnetic field‐induced distortion correction applied to diffusion weighted MRI of the breast at 3T
Authors: Teruel Jose R. , Fjøsne Hans E. , Østlie Agnes , Holland Dominic , Dale Anders M. , Bathen Tone F. , Goa Pål E. 
Published: October 2014

PurposeTo evaluate the performance of an advanced method for correction of inhomogeneous static magnetic field induced distortion in echo‐planar imaging (EPI), applied to diffusion‐weighted MRI (DWI) of the breast.MethodsAn algorithm for distortion correction based on the symmetry of the distortion induced by static field inhomogeneity when the phase encoding polarity is reversed was evaluated in 36 data sets of patients who received an MRI examination that included DWI (b = 0 and 700 s/mm2) and an extra b = 0 s/mm2 sequence with opposite phase encoding polarity. The decrease of the L2‐square norm after correction between opposed phase encoding b = 0 images was calculated. Mattes mutual information between b = 0 images and fat‐suppressed T2‐weighted images was calculated before and after correction.ResultsThe L2‐square norm between different phase encoding polarities for b = 0 images was reduced 94.3% on average after distortion correction. Furthermore, Mattes mutual information between b = 0 images and fat‐suppressed T2‐weighted images increased significantly after correction for all cases (P < 0.001).ConclusionGeometric distortion correction in DWI of the breast results in higher similarity of DWI to anatomical non‐EPI T2‐weighted images and would potentially allow for a more reliable lesion segmentation mapping among different MRI modalities. Magn Reson Med 74:1138–1144, 2015. © 2014 Wiley Periodicals, Inc.
Combining phase and magnitude information for contrast agent quantification in dynamic contrast‐enhanced MRI using statistical modeling
Authors: Brynolfsson Patrik , Yu Jun , Wirestam Ronnie , Karlsson Mikael , Garpebring Anders 
Published: October 2014

PurposeThe purpose of this study was to investigate, using simulations, a method for improved contrast agent (CA) quantification in DCE‐MRI.MethodsWe developed a maximum likelihood estimator that combines the phase signal in the DCE‐MRI image series with an additional CA estimate, e.g. the estimate obtained from magnitude data. A number of simulations were performed to investigate the ability of the estimator to reduce bias and noise in CA estimates. Noise levels ranging from that of a body coil to that of a dedicated head coil were investigated at both 1.5T and 3T.ResultsUsing the proposed method, the root mean squared error in the bolus peak was reduced from 2.24 to 0.11 mM in the vessels and 0.16 to 0.08 mM in the tumor rim for a noise level equivalent of a 12‐channel head coil at 3T. No improvements were seen for tissues with small CA uptake, such as white matter.ConclusionPhase information reduces errors in the estimated CA concentrations. A larger phase response from higher field strengths or higher CA concentrations yielded better results. Issues such as background phase drift need to be addressed before this method can be applied in vivo. Magn Reson Med 74:1156–1164, 2015. © 2014 Wiley Periodicals, Inc.
Power balance and loss mechanism analysis in RF transmit coil arrays
Authors: Kuehne Andre , Goluch Sigrun , Waxmann Patrick , Seifert Frank , Ittermann Bernd , Moser Ewald , Laistler Elmar 
Published: October 2014

PurposeTo establish a framework for transmit array power balance calculations based on power correlation matrices to accurately quantify the loss contributions from different mechanisms such as coupling, lumped components, and radiation.Theory and MethodsStarting from Poynting's theorem, power correlation matrices are derived for all terms in the power balance, which is formulated as a matrix equation. Finite‐difference time‐domain simulations of two 7 T eight‐channel head array coils at 297.2 MHz are used to verify the theoretical considerations and demonstrate their application. Care is taken to accurately incorporate all loss mechanisms. The power balance for static B1 phase shims as well as two‐dimensional spatially selective transmit SENSE pulses is shown.ResultsThe simulated power balance shows an excellent agreement with theory, with a maximum power imbalance of less than 0.11%. Power loss contributions from the different loss mechanisms vary significantly between the investigated setups, and depending on the excitation mode imposed on the coil.ConclusionThe presented approach enables a straightforward loss evaluation for an arbitrary excitation of transmit coil arrays. Worst‐case power imbalance and losses are calculated in a straightforward manner. This allows for deeper insight into transmit array loss mechanisms, incorporation of radiated power components in specific absorption rate calculations and verification of electromagnetic simulations. Magn Reson Med 74:1165–1176, 2015. © 2014 Wiley Periodicals, Inc.
Generalized Kronecker product splitting iteration for the solution of implicit Runge–Kutta and boundary value methods
Authors: Chen Hao 
Published: October 2014

SummaryThis paper is concerned with a generalization of the Kronecker product splitting (KPS) iteration for solving linear systems arising in implicit Runge–Kutta and boundary value methods discretizations of ordinary differential equations. It is shown that the new scheme can outperform the standard KPS method in some situations and can be used as an effective preconditioner for Krylov subspace methods. Numerical experiments are presented to demonstrate the effectiveness of the methods. Copyright © 2014 John Wiley & Sons, Ltd.
Dimensionality and Reliability of the Self‐Care of Heart Failure Index Scales: Further Evidence From Confirmatory Factor Analysis
Authors: Barbaranelli Claudio , Lee Christopher S. , Vellone Ercole , Riegel Barbara 
Published: October 2014

AbstractThe Self‐Care of Heart Failure Index (SCHFI) is used widely, but issues with reliability have been evident. Cronbach alpha coefficient is usually used to assess reliability, but this approach assumes a unidimensional scale. The purpose of this article is to address the dimensionality and internal consistency reliability of the SCHFI. This was a secondary analysis of data from 629 adults with heart failure enrolled in three separate studies conducted in the northeastern and northwestern United States. Following testing for scale dimensionality using confirmatory factor analysis, reliability was tested using coefficient alpha and alternative options. Confirmatory factor analysis demonstrated that: (a) the Self‐Care Maintenance Scale has a multidimensional four‐factor structure; (b) the Self‐Care Management Scale has a two‐factor structure, but the primary factors loaded on a common higher‐order factor; and (c) the Self‐Care Confidence Scale is unidimensional. Reliability estimates for the three scales, obtained with methods compatible with each scale's dimensionality, were adequate or high. The results of the analysis demonstrate that issues of dimensionality and reliability cannot be separated. Appropriate estimates of reliability that are consistent with the dimensionality of the scale must be used. In the case of the SCHFI, coefficient alpha should not be used to assess reliability of the self‐care maintenance and the self‐care management scales, due to their multidimensionality. When performing psychometric evaluations, we recommend testing dimensionality before assessing reliability, as well using multiple indices of reliability, such as model‐based internal consistency, composite reliability, and omega and maximal reliability coefficients. © 2014 Wiley Periodicals, Inc.