bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self‐sufficient minority carrier lifetime in silicon from quasi‐steady‐state photoluminescence
Authors: Giesecke J. A. , Schubert M. C. , Warta W. 
Published: August 2012

AbstractQuasi‐steady‐state photoluminescence is a versatile technique to determine carrier lifetime in silicon. A recent approach extracts carrier lifetime without a priori information about dopant concentration [Appl. Phys. Lett. 97, 092109 (2010)]. It utilizes the phase shift between a time‐modulated optical irradiation and the radiative recombination of a sample, while requiring a minimum of two measurements. The present paper is aimed at a generalization thereof that requires only one measurement. It brings about a substantial experimental simplification, significantly improved accuracy and precision, and it opens up paths to access material properties other than lifetime.
Development of electrospray ionization tandem mass spectrometry methods for the study of a high number of urine markers of inborn errors of metabolism
Authors: Rebollido‐Fernandez M. Maira , Castiñeiras Daisy E. , Dolores Bóveda M. , Luz Couce M. , Cocho José A. , Fraga Jose M. 
Published: August 2012

RATIONALERapid and specific screening methods to detect abnormal metabolites in biological fluids are important for the diagnosis of many Inborn Errors of Metabolism (IEM). In Galicia (N.W. Spain), where newborn screening (NBS) has long used both blood and urine dried samples, an expanded NBS by tandem mass spectrometry (MS/MS) begun in July 2000 analyzing amino acids and acylcarnitines in blood. The purpose of this study is the development of methods to widen and to complement the present NBS with the study of the selected metabolites in urine.METHODSWe studied and optimized the fragmentation of a total of 96 marking compounds of IEM, as well as 34 isotopically labeled internal standards (IS). The isobaric interferences were resolved with the use of alternative fragmentation in 14 of the 28 groups found. The methods were validated for 68 compounds following the recommendations of the NCCLS.RESULTSWe have developed electrospray ionization (ESI)‐ MS/MS methods in positive and negative ionization modes to detect selected metabolites in urine. The study was performed by direct injection of amino acids and acylcarnitines in positive mode, and organic acids, acylglycines, purines and pyrimidines in negative mode. Run times were 2.5 and 2.6 min, respectively, allowing the daily analysis of a high number of samples.CONCLUSIONSThe validated methods were proved effective for the simultaneous study of a large number of metabolites which are commonly present in urine samples and are used for detecting IEM. The evaluation was done by searching diagnostic profiles with multiple markers to increase sensitivity and specificity (e.g., acylcarnitines plus amino acids) or with specific urine markers (cystine, homogentisic acid, sialic acid, N‐acetylaspartic acid, etc.). Copyright © 2012 John Wiley & Sons, Ltd.
Complementary Fe3+‐ and Ti4+‐immobilized metal ion affinity chromatography for purification of acidic and basic phosphopeptides
Authors: Lai Alan Chuan‐Ying , Tsai Chia‐Feng , Hsu Chuan‐Chih , Sun Yu‐Ni , Chen Yu‐Ju 
Published: August 2012

RATIONALEDespite advances in mass spectrometry (MS)‐based identification, effective phosphopeptide enrichment is a prerequisite towards comprehensive phosphoproteomic analysis. Based on the different binding affinities and coordination geometries of the Ti4+ and Fe3+ ions with the phosphate group, we report a complementary metal‐directed immobilized metal ion affinity chromatography (IMAC) method to increase the identification coverage of a phosphoproteome.METHODSPhosphopeptides from standard phosphoproteins and Raji B cells were enriched from Ti4+‐IMAC and Fe3+‐IMAC methods, followed by matrix‐assisted laser desorption/ionization (MALDI) MS and Orbitrap MS analysis. Optimal enrichment specificity was achieved by selection of acid structure/concentration and organic solvent to compete with non‐phosphopeptides. The effect of the metal ion and the chelating compound was evaluated by the comparison of the characteristics of enriched phosphopeptides between Ti4+‐IMAC, Fe3+‐IMAC and TiO2 methods.RESULTSTo address the low enrichment specificity of the Ti4+‐IMAC method, a simple one‐step acid/solvent controlled IMAC method was developed with significantly improved specificity (88%) and recovery (93%). The most striking discovery is that the optimal Ti4+‐IMAC and Fe3+‐IMAC methods have low overlapping percentage (10%) among the 2905 enriched phosphopeptides from Raji cells, comprised of the distinct characteristics including hydrophobicity, amino acid compositions, and frequency of multiple phosphorylation of the phosphopeptides.CONCLUSIONSThe reported Fe3+‐IMAC and Ti4+‐IMAC methods can complementarily enrich acidic and basic phosphopeptides to effectively increase the identification coverage of an heterogeneous phosphoproteome (twice than the single approach). Given the reproducibility and low sample loss, the combination of our enrichment strategy with a quantitative technique could be feasible for quantitative phosphoproteomics. Copyright © 2012 John Wiley & Sons, Ltd.
Identification by mass spectrometry of new compounds arising from the reactions involving malvidin‐3‐glucoside‐(O)‐catechin, catechin and malvidin‐3‐glucoside
Authors: Cruz Luís , Mateus Nuno , de Freitas Victor 
Published: August 2012

RATIONALEThe aim of this work was to study the putative reactions that could occur in red wines between malvidin‐3‐glucoside‐(O)‐catechin (mv3glc‐(O)‐cat) adduct and catechin (cat) or malvidin‐3‐glucoside (mv3glc) in presence of acetaldehyde.METHODSMv3glc‐(O)‐cat adduct (1 mM) was incubated with catechin (or mv3glc) in the presence of acetaldehyde (molar ratio of 1:4:10) in 12% ethanol/water at pH 3.2, protected from light and placed in the oven at 30 °C. The formation of the new compounds was monitored by liquid chromatography‐diode‐array detection/electrospray ionization mass spectrometry (LC‐DAD/ESI‐MS) analysis in the positive and negative ion mode.RESULTSThe LC‐DAD/ESI‐MS characterization allowed the confirmation of the structures of the methylmethine‐linked cat‐mv3glc‐(O)‐cat ([M–H]– m/z 1097) and mv3glc‐mv3glc‐(O)‐cat ([M]+ m/z 1301) adducts.CONCLUSIONSThe studies performed in model solutions showed that the colorless mv3glc‐(O)‐cat adduct can undergo some of the characteristic reactions of anthocyanins and flavan‐3‐ols that occur in red wine in the presence of acetaldehyde forming new methylmethine‐bridged compounds. Copyright © 2012 John Wiley & Sons, Ltd.
Monte Carlo Simulation of CD‐SEM Images for Linewidth and Critical Dimension Metrology
Authors: Li Y. G. , Zhang P. , Ding Z. J. 
Published: August 2012

SummaryIn semiconductor industry, strict critical dimension control by using a critical dimension scanning electron microscope (CD‐SEM) is an extremely urgent task in near‐term years. A Monte Carlo simulation model for study of CD‐SEM image has been established, which is based on using Mott's cross section for electron elastic scattering and the full Penn dielectric function formalism for electron inelastic scattering and the associated secondary electron (SE) production. In this work, a systematic calculation of CD‐SEM line‐scan profiles and 2D images of trapezoidal Si lines has been performed by taking into account different experimental factors including electron beam condition (primary energy, probe size), line geometry (width, height, foot/corner rounding, sidewall angle, and roughness), material properties, and SE signal detection. The influences of these factors to the critical dimension metrology are investigated, leading to build a future comprehensive model‐based library. SCANNING 35: 127‐139, 2013. © 2012 Wiley Periodicals, Inc.
Cortisol Responses to Naturalistic and Laboratory Stress in Student Teachers: Comparison with a Non‐stress Control Day
Authors: Wolfram Maren , Bellingrath Silja , Feuerhahn Nicolas , Kudielka Brigitte M. 
Published: August 2012

AbstractAmbulatory assessments of hypothalamus–pituitary–adrenal axis responses to acute natural stressors yield evidence on stress regulation with high ecological validity. Sampling of salivary cortisol is a standard technique in this field.In 21 healthy student teachers, we assessed cortisol responses to a demonstration lesson. On a control day, sampling was repeated at analogous times. Additionally, the cortisol awakening response (CAR) was assessed on both days. Participants were also exposed to a laboratory stressor, the Trier Social Stress Test, and rated their individual levels of chronic work stress.In pre‐to‐post‐stress assessment, cortisol levels declined after the lesson. However, post‐stress cortisol levels were significantly higher compared with those on the control day. Also, the Trier Social Stress Test yielded higher cortisol responses when using the control day as reference baseline. Associations between the CAR and chronic stress measures were observed solely on the control day. There were no significant associations between cortisol responses to the natural and laboratory stressors.Our results indicate that a control day might be an important complement in laboratory but especially in ambulatory stress research. Furthermore, associations between chronic stress measures and the CAR might be obscured by acute stress exposure. Finally, responses to the laboratory stressor do not seem to mirror natural stress responses. Copyright © 2012 John Wiley & Sons, Ltd.
Nanoscale Magnetic Characterization of Tunneling Magnetoresistance Spin Valve Head by Electron Holography
Authors: Park Hyun Soon , Hirata Kei , Yanagisawa Keiichi , Ishida Yoichi , Matsuda Tsuyoshi , Shindo Daisuke , Tonomura Akira 
Published: August 2012

AbstractNanostructured magnetic materials play an important role in increasing miniaturized devices. For the studies of their magnetic properties and behaviors, nanoscale imaging of magnetic field is indispensible. Here, using electron holography, the magnetization distribution of a TMR spin valve head of commercial design is investigated without and with a magnetic field applied. Characterized is the magnetic flux distribution in complex hetero‐nanostructures by averaging the phase images and separating their component magnetic vectors and electric potentials. The magnetic flux densities of the NiFe (shield and 5 nm‐free layers) and the CoPt (20 nm‐bias layer) are estimated to be 1.0 T and 0.9 T, respectively. The changes in the magnetization distribution of the shield, bias, and free layers are visualized in situ for an applied field of 14 kOe. This study demonstrates the promise of electron holography for characterizing the magnetic properties of hetero‐interfaces, nanostructures, and catalysts.
Biomedical applications of multifunctional plasmonic nanoparticles
Authors: Sotiriou Georgios A. 
Published: August 2012

AbstractPlasmonic nanoparticles play an important role in biomedical applications today as they can serve as superior, optically stable bioimaging agents, be employed in biosensor devices for the early diagnosis of diseases, and exhibit promising results in vivo as therapeutic agents. For several bioapplications, however, nanoparticles that express more than one functionality are often advantageous. This has led to the synthesis of multifunctional plasmonic nanostructures that combine the attractive plasmonic properties with other functionalities such as magnetism, photoluminescence, dispersibility in aqueous solutions, and resistance to degradation. Such multifunctional nanoparticles can be detected by multiple imaging techniques including magnetic resonance imaging and fluorescence microscopy. Furthermore, their performance in diagnostics and therapy (theranostics) can be significantly improved facilitating the early detection of diseases. The possibility to tune the desired properties enables such hybrid nanoparticles to be employed in vivo as therapeutic agents that can actively target tumor sites and destroy them by external means. This makes such bionanoprobes ideal candidates for non‐ or minimally invasive cancer treatments. Through rational design and engineering, ‘smart’ multifunctional nanomaterials with unprecedented properties can be made that will lead the nano‐based theranostics in the future. WIREs Nanomed Nanobiotechnol 2013, 5:19–30. doi: 10.1002/wnan.1190This article is categorized under:

Diagnostic Tools > Biosensing
Therapeutic Approaches and Drug Discovery > Emerging Technologies
Diagnostic Tools > In Vitro Nanoparticle-Based Sensing
Diagnostic Tools > In Vivo Nanodiagnostics and Imaging
Adult Fingers Visualized on Neonatal Intensive Care Unit Chest Radiographs: What You Don't See
Authors: Russell Jordan , Burbridge Brent E. , Duncan Meghan D. , Tynan Jennifer 
Published: August 2012

Purpose In a previous publication, it was revealed that a disturbingly high incidence of adult fingers were seen on pediatric intensive care unit radiographs, an example of inappropriate occupational exposure to diagnostic radiation. The present study examined adult fingers seen on neonatal intensive care unit (NICU) radiographs to assess the frequency of this occupational radiation exposure. During this study, we encountered an unexpected issue. The inappropriately exposed fingers appeared on the raw images but were sometimes cropped during technologist image processing before being sent to the picture archiving and communication system (PACS) for interpretation. Our audit describes the frequency of cropping adult fingers from images before display on PACS, with the intent of unmasking this source of occupational radiation exposure, of which quality assurance personnel may not be aware. Methods At the x-ray workstation, the raw NICU source x-ray images were analysed for the visibility of adult fingers and then were compared with the final processed images sent to PACS by the x-ray technologist. Results Of 230 radiographs audited, 30 (13%) contained fingers directly in the x-ray beam that remained visible on PACS, 22 (10%) contained fingers in the direct beam that were cropped before being sent to PACS for analysis, and 44 (19%) contained fingers in the coned area. Conclusions A significant number of adult fingers are being exposed to radiation during the acquisition of NICU radiographs. Cropping NICU radiographs before sending them to PACS can conceal a significant source of occupational radiation exposure.
Global progress and potentially effective policy responses to reduce maternal mortality
Authors: Mbizvo Michael T. , Say Lale 
Published: August 2012

AbstractReducing maternal mortality within significant margins is a global imperative that reflects attainment of development goals. Progress in reducing maternal mortality, in particular among countries with notably high maternal mortality ratios (MMRs), has been substantially slower than the Millennium Development Goal target of an annual rate of 5.5% decline. The latest UN maternal mortality estimates show a reduction in MMR in a number of countries between 1990 and 2008. Understanding the factors associated with progress in countries that have reduced maternal mortality provides other countries and development partners with opportunities to consider and implement policies and interventions that could help accelerate progress. This paper reviews 6 countries that have demonstrated marked progress. The policies that have been effective include innovative financing measures; investment in human resources both in terms of strengthening pre‐service education and emphasizing in‐service training for healthcare providers; strengthening obstetric care by enhancing infrastructure and upgrading equipment, as well as improving quality of services; and investing in the broader determinants of maternal mortality, particularly family planning and women's education and socioeconomic empowerment. This range of actions, which includes a combination of facility and community‐based approaches, provides a list of potentially effective strategies that could be considered when developing programs in other countries with slower progress. Strong political will and multistakeholder involvement and interventions are key in the development and implementation of these policies and actions.
Misoprostol for prevention and treatment of postpartum hemorrhage: What do we know? What is next?
Authors: Raghavan Sheila , Abbas Dina , Winikoff Beverly 
Published: August 2012

AbstractMisoprostol is an effective and safe uterotonic for the prevention and treatment of postpartum hemorrhage (PPH). A 600‐μg oral dose of misoprostol has been shown to prevent PPH in community‐based randomized controlled trials. An 800‐μg sublingual dose of misoprostol appears to be a good first‐line treatment for controlling PPH. Adverse effects after use of misoprostol for PPH prevention or treatment may include shivering and fever. These effects are transient, resolve on their own, and are not life threatening. Misoprostol can play an important role in settings with limited access to oxytocin, and where there is no other option for PPH care.
The involvement of agencies in policy formulation: Explaining variation in policy autonomy of federal agencies in Germany
Authors: Bach Tobias 
Published: August 2012

AbstractThe article addresses how government agencies perceive their own role and relationship with their parent ministry in policy formulation. Although a growing body of literature suggests that agencies are frequently granted this type of policy autonomy from their parent ministries, there is little systematic knowledge about why some agencies have more policy autonomy than others. The article analyzes data from a large-N survey of federal agencies in Germany, examining the self-perception of federal agencies with regard to policy formulation and feed-back on policy effectiveness. The article uses task characteristics, formal–legal structure, and cultural aspects of ministry–agency relations as main explanatory factors. A key result of this research is that task characteristics are more important for explaining policy autonomy than structural and cultural characteristics.
Agencies and policy in an administrative state: The case of Hong Kong
Authors: Painter Martin , Yee Wai-Hang 
Published: August 2012

Abstract
A survey of agency chief executives in Hong Kong found that they perceive themselves to have high levels of policy autonomy. This could be interpreted in two ways: either that agency chiefs perceive they can exert power over their ‘principals’ through taking advantage of information asymmetries and by adopting other stratagems to evade supervision; or that they feel they possess influence through mutually supportive participation in policy-making with their supervising bureau officials and principal officials (or ‘ministers’). The institutional context of Hong Kong's administrative state, in particular the integrated and inclusive nature of the civil service career system; the absence of an elected political leadership; and the key representational roles played by various boards and panels associated with agencies, makes the second interpretation more plausible. In support of this argument, evidence is drawn from interviews with senior officials in seven Hong Kong agencies, supported by case study material. We find evidence of a number of aspects of the policy roles of agencies which are mutually agreed, rational adaptations to this institutional context, such as partitioning the policy field (when the political executive and the supervising policy bureau formally or informally vacate part of the policy field and delegate it to the agency); filling a policy vacuum (when the political executive voluntarily vacates the field altogether); and acting in a segmented policy process (when agencies are allowed to take the lead in agenda-setting and/or exercise high levels of flexibility and adaptability in the implementation process). These features of relations between agencies, policy bureaus and the political executive are not the product of principal–agent conflict but of mutual cooperation and adaptation.
Elasto-Plastic Analysis of Thick Cylinders Subjected to Internal Electro-Magnetic Loading
Authors: Rajabi H. , Darvizeh A. 
Published: August 2012

AbstractA study of elasto-plastic deformation of circular cylindrical shells subjected to internal electromagnetic forces is presented in this paper. The five governing equations in terms of resultant forces and resultant moments with respect to basic displacement vector components u, v and w are used. Theoretical formulations, based on the first-order shear deformation theory (FSDT), take into consideration transverse shear deformation and rotary inertia. The deformation theory of plasticity is employed for constitutive equations. The cylinders are composed of an elastic-plastic material with the von Mises yield criteria and non-linear plastic behaviour. Galerkin method is employed to convert the partial differential equations (PDEs) to ordinary differential equations (ODEs). The Newmark family of methods is used to numerically time integration of system of coupled second order ODEs. In order to prove the validity of the presented method and the solving process, the results obtained with the present analysis are compared with a set of available data. Good agreement observed between the results of the two approaches. Certainly, the aim of this paper is to create a more reliable and precise mathematical model of hollow-cylinders to avoid performing several experiments.
MHD Stability of Streaming Jet Using Artificial Intelligence Technique
Authors: Abdeen Mostafa A. M. , Hasan Alfaisal A. 
Published: August 2012

AbstractMathematical formulation for Magnetohydrodynamic (MHD) stability of a streaming cylindrical model penetrated by varying transverse magnetic field is presented. Eigen value relation is derived and discussed analytically. In the current paper, Artificial Neural Network (ANN) model, one of the artificial intelligence techniques, is developed to simulate the stability of streaming jet penetrated by magnetic field. The ANN results presented in the current study showed that ANN technique, with less effort and time, is very efficiently capable of simulating and predicting the effect of magnetic field variation and axial exterior field on the stability of the streaming jet. The influence of magnetic field has a stabilizing effect for all short and long wavelengths. However the streaming is strongly destabilizing.
Bending Analysis of Thin Plates with Variable Thickness Resting on Elastic Foundation by Element Free Galerkin Method
Authors: Rahbar-Ranji Ahmad , Bahmyari E. 
Published: August 2012

AbstractElement Free Galerkin method was used to analyze bending of thin plates with variable thickness resting on one parameter elastic foundation. Thickness of plate is considered as linearly varying in one direction. Formulation could be applied to plates of any shape with general boundary conditions and loadings. Convergence of solution was examined for different number of nodes, thickness variation and foundation parameters. It was found that for deflection good results were achieved even with small number of nodes regardless of boundary condition, thickness variation and foundation parameters. Accuracy of method is checked against available results and good agreements were found. Applicability of method is demonstrated by solving numerical examples with different boundary conditions, thickness and foundation parameters, and loadings.