bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transient Response of Particle Distribution in a Chamber to Transient Particle Injection
Authors: Zhang Ning , Zheng Zhongquan , Eckels Steven , Nadella Venkata B. , Sun Xiaoyang 
Published: January 2010

AbstractWe inject a large number of newly created nano‐particle aggregates into a chamber for the purpose of removing harmful contents in an indoor environment. This study is to experimentally and numerically investigate transient response of particle distributions to particle injections. A room‐sized chamber of 4 m × 2.1 m × 2.4 m is connected to a specially designed particle‐injection system, with two Optical Particle Counters used to simultaneously measure particle‐number densities with the size range from 0.3 μm to 10 μm at the inlet and in the chamber. A velocity probe measures the flow that is up to 1 m/s. An Euler‐type particulate‐phase‐transport model is developed and validated by comparing with experimental data. The study shows that the transient behavior of particle distributions is determined by many factors, including particle size, particle settling speed, sampling location, and velocity distribution. Particle number densities decrease in time more quickly for large particles than for small particles, and locations farther downstream in the chamber correlate more weakly with the inlet injection.
Deconvolution with Maximum Entropy Solution to Determine Local Extinction Coefficient and Local Volume Concentration Values from Laser Diffraction Data
Authors: Yongyingsakthavorn Pisit , Dumouchel Christophe , Vallikul Pumyos , Fungtammasan Bundit 
Published: January 2010

AbstractThe traditional use of the laser diffraction technique provides line‐of‐sight liquid spray drop‐size distribution. However, deconvolution of the measurements can be performed for axisymmetric spray in order to determine local spray characteristics. In a previous publication, a new deconvolution technique making use of the maximum entropy principle was established and applied to determine the local drop‐size distributions. The entire approach was experimentally validated. In this work, the technique is employed to determine local extinction coefficient values. As in the previous investigation, the measurement procedure consists of scanning a laser beam through the spray cross‐section from the center to the edge of the spray. By use of the transmittance theory, the local extinction coefficients allow the local volume concentrations to be calculated. This theory introduces the mean scattering coefficient. The results show that this coefficient must be determined as a function of the Sauter mean diameter in order to avoid overestimation of the volume concentration. Although no proper validation is presented, the coherence of the overall approach is discussed in detail and solutions for improving the spatial resolution are presented. Finally, the local volume concentrations are combined with the local drop‐size distribution to provide local volume‐weighted, drop‐size distributions. These distributions provide information on the localization of the drops according to their diameter as well as on the spatial liquid distribution. This work illustrates applications and performances of laser diffraction technique that are rarely used.
Differential regulation of redox proteins and chaperones in HbEβ‐thalassemia erythrocyte proteome
Authors: Bhattacharya Dipankar , Saha Sutapa , Basu Sumanta , Chakravarty Sudipa , Chakravarty Amit , Banerjee Debashis , Chakrabarti Abhijit 
Published: January 2010

AbstractPurpose: In (hemoglobin, Hb) HbEβ‐thalassemia, HbE (β‐26 Glu→Lys) interacts with β‐thalassemia to produce clinical manifestation of varying severity. This is the first proteomic effort to study changes in protein levels of erythrocytes isolated from HbEβ‐thalassemic patients compared to normal.Experimental design: We have used 2‐DE and MALDI‐MS/MS‐based techniques to investigate the differential proteome profiling of membrane and Hb‐depleted fraction of cytosolic proteins of erythrocytes isolated from the peripheral blood samples of HbEβ‐thalassemia patients and normal volunteers.Results: Our study showed that redox regulators such as peroxiredoxin 2, Cu‐Zn superoxide dismutase and thioredoxin and chaperones such as α‐hemoglobin stabilizing protein and HSP‐70 were upregulated in HbEβ‐thalassemia. We have also observed larger amounts of membrane associated globin chains and indications of disruption of spectrin‐based junctional complex in the membrane skeleton of HbEβ‐thalassemic erythrocytes upon detection of low molecular weight fragments of β‐spectrin and decrease in β‐actin and dematin content.Conclusion and clinical relevance: We have observed interesting changes in the proteomic levels of redox regulators and chaperons in the thalassemic hemolysates and have observed strong correlation or association of the extent of such proteomic changes with HbE levels. This could be important in understanding the role of HbE in disease progression and pathophysiology.
Biomarkers of neurological status in HIV infection: A 3‐year study
Authors: Ragin Ann B. , Wu Ying , Ochs Renee , Scheidegger Rachel , Cohen Bruce A. , Edelman Robert R. , Epstein Leon G. , McArthur Justin 
Published: January 2010

AbstractPurpose: To evaluate circulating cytokines and chemokines as correlates of the degree of brain injury in individuals with advanced human immunodeficiency virus (HIV) infection.Experimental design: Study participants included ten well‐characterized subjects in advanced stage HIV infection. High‐throughput multiplexed analysis was used to quantify markers of interest at baseline and 3 years later in the clinical course. Objective measurements of the brain were derived in vivo with quantitative magnetic resonance segmentation algorithms and with diffusion tensor imaging.Results: Of the markers examined, monocyte chemoattractant protein‐1 (MCP‐1 or CCL‐2) was the most prominent correlate of brain injury. Elevated MCP‐1 levels correlated with brain white matter alterations at the initial assessment. The relationship to injury was more extensive 3 years later; elevated MCP‐1 was significantly correlated with measures of brain microstructural alterations and of abject atrophy.Conclusions and clinical relevance: The findings build on our prior observations that elevated MCP‐1 levels may be a useful predictive marker for HIV‐associated neurocognitive disorder. As a potent chemoattractant, MCP‐1 may mediate injury through participation in self‐reinforcing cycles of chronic immune activation and cytokine/chemokine‐mediated neurotoxicity.
Proteomic analysis of BRCA1‐depleted cell line reveals a putative role for replication protein A2 up‐regulation in BRCA1 breast tumor development
Authors: Bouley Julien , Pionneau Cédric , Varinot Justine , Biard Denis , Genestie Catherine , Antoine Martine , Coulet Florence , Stern Marc‐Henri , Stoppa‐Lyonnet Dominique , Soubrier Florent 
Published: January 2010

AbstractPurpose: Germline mutations in BRCA1 result in a strong predisposition to breast cancer, with frequent loss of heterozygosity of the remaining wild‐type allele. The development of BRCA1 tumors is likely to depend on additional genetic alterations and gene expression changes which follow growth and DNA repair defects associated with BRCA1 deficiency. The identification of these modifications offers an opportunity to find surrogate markers of BRCA1 tumors. Here, we sought to identify differentially expressed proteins related to BRCA1 depletion.Experimental design: We used isogenic HeLa cells either stably knocked‐down or not for BRCA1 (BRCA1KD) and compared protein profiles of these cells by DIGE.Results: We detected increased levels of Replication protein A2 (RPA2) in BRCA1KD cells as compared to control cells. RPA2 is an essential protein required for DNA replication and repair. We further demonstrated that depletion of RPA2 subunit delays growth of BRCA1KD respect to isogenic control cells. Strikingly, elevated levels of RPA2 were more frequently observed in BRCA1 tumors when triple‐negative tumors from BRCA1 mutation carriers (n=13) and non‐carriers (n=36) were stained in situ for RPA2.Conclusions and clinical relevance: RPA2 up‐regulation may thus be involved in the growth and/or survival of BRCA1 tumor cells and useful in immunohistochemical discrimination of triple‐negative BRCA1 tumors.
Combining laser capture microdissection and proteomics: Methodologies and clinical applications
Authors: Xu Baogang J. 
Published: January 2010

AbstractLaser capture microdissection (LCM) has become an important tool for biomedical research. Various molecular biology techniques have been combined with LCM to reveal molecular profiles at an unprecedented tissue resolution. Proteomics is among those techniques that have proved fruitful in combination with LCM. This review provides an overview of the various proteomic techniques that have been developed for analyzing cells obtained using LCM. Methods for analyzing microdissected cells for various proteomic techniques are described and compared. In addition, various applications based on LCM and proteomics are discussed.
Optimization protocol for amyloid‐β peptides detection in human cerebrospinal fluid using SELDI TOF MS
Authors: Albertini Valentina , Bruno Anna , Paterlini Anna , Lista Simone , Benussi Luisa , Cereda Cristina , Binetti Giuliano , Ghidoni Roberta 
Published: January 2010

AbstractPurpose: The aim of the present work was to set up an optimized protocol for human cerebrospinal fluid amyloid‐β (Aβ) profiling.Experimental design: We devised an immunoproteomic assay that employs monoclonal antibodies (mAbs) on Preactivated Surface (PS20) chip array followed by SELDI TOF MS. A comparison of a number of factors was performed, and the impact of these differences was noted. Each variable was tested using in parallel two different mAbs, 6E10 and 4G8. In addition, we tested whether the combined use of these two mAbs could improve the capture of N and C‐terminally truncated Aβ peptides and then the quality of spectra.Results: The best results were obtained using a mixture of Aβ mAbs (0.125μg/μL 6E10+4G8): 15 Aβ peptides (including 3 N‐terminally truncated forms) were detected.Conclusions and clinical relevance: This approach has many potential advantages in speed, sensitivity and economy of reagents and could be helpful in order to define the role played by specific Aβ truncated forms in cognitive decline.
Multiplex assays for biomarker research and clinical application: Translational science coming of age
Authors: Fu Qin , Schoenhoff Florian S. , Savage William J. , Zhang Pingbo , Van Eyk Jennifer E. 
Published: January 2010

AbstractOver the last decade, translational science has come into the focus of academic medicine, and significant intellectual and financial efforts have been made to initiate a multitude of bench‐to‐bedside projects. The quest for suitable biomarkers that will significantly change clinical practice has become one of the biggest challenges in translational medicine. Quantitative measurement of proteins is a critical step in biomarker discovery. Assessing a large number of potential protein biomarkers in a statistically significant number of samples and controls still constitutes a major technical hurdle. Multiplexed analysis offers significant advantages regarding time, reagent cost, sample requirements and the amount of data that can be generated. The two contemporary approaches in multiplexed and quantitative biomarker validation, antibody‐based immunoassays and MS‐based multiple (or selected) reaction monitoring, are based on different assay principles and instrument requirements. Both approaches have their own advantages and disadvantages and therefore have complementary roles in the multi‐staged biomarker verification and validation process. In this review, we discuss quantitative immunoassay and multiple reaction monitoring/selected reaction monitoring assay principles and development. We also discuss choosing an appropriate platform, judging the performance of assays, obtaining reliable, quantitative results for translational research and clinical applications in the biomarker field.
Banking of clinical samples for proteomic biomarker studies: A consideration of logistical issues with a focus on pre‐analytical variation
Authors: Jackson David H. , Banks Rosamonde E. 
Published: January 2010

AbstractBiobanks with their collections of clinical samples and data are essential resources for the success of clinical proteomics in delivering and validating candidate biomarkers. Samples must be banked in a manner that allows maximum subsequent compatibility with analytical techniques and additionally many critical factors must be taken into account when establishing a biobank or selecting samples from a biobank. These include logistical, ethical, legal and security issues and, very importantly, steps to minimise any pre‐analytical variability introduced through sample processing and handling (technical effects). The inherent variation present within the samples must also be taken into account. In this review, we examine the impact of these factors and issues to be faced when banking samples with a particular focus on sources of pre‐analytical variation, which must be rigorously controlled and recorded. It is encouraging that several initiatives are now addressing such key issues and these are also discussed.
An improved procedure for the synthesis of dehydroamino acids and dehydropeptides from the carbonate derivatives of serine and threonine using tetrabutylammonium fluoride
Authors: Ramapanicker Ramesh , Mishra Roli , Chandrasekaran Srinivasan 
Published: January 2010

AbstractDehydroamino acids are important precursors for the synthesis of a number of unnatural amino acids and are structural components in many biologically active peptide derivatives. However, efficient synthetic procedures for their production in large amounts and without side reactions are limited. We report here an improved procedure for the synthesis of dehydroalanine and dehydroamino butyric acid from the carbonate derivatives of serine and threonine using TBAF. The antiselective E2 elimination of the carbonate derivatives of serine and threonine using TBAF is milder and more efficient than other available procedures. The elimination reaction is completed in less than 10 min with various carbonate derivatives studied and the methodology is very efficient for the synthesis of dehydroamino acids and dehydropeptides. The procedure thus provides an easy access to key synthetic precursors and can be used to introduce interesting structural elements to designed peptides. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Modeling quantum dot lasers with optical feedback: sensitivity of bifurcation scenarios
Authors: Otto Christian , Lüdge Kathy , Schöll Eckehard 
Published: January 2010

AbstractWe present a systematic study of the complex dynamics of a quantum dot (QD) laser subjected to optical feedback from a short external cavity. Our model consists of a Lang–Kobayashi like model for the electric field combined with a microscopically based rate equation system. We separately treat electron and hole dynamics in the QDs and the surrounding wetting layer (WL). By tuning the phase–amplitude coupling and the optical confinement factor we are able to discuss various scenarios of the dynamics on the route towards conventional quantum well (QW) lasers. Due to the optical feedback, multistability occurs in our model in form of external cavity modes (ECMs) or delay‐induced intensity pulsations. In dependence of the feedback strength we analyze complex bifurcation scenarios for the intensity of the emitted laser light as well as time series, power spectra, and phase portraits of all dynamic variables in order to elucidate the internal dynamics of the laser.
Theoretical study of structural and optical properties of small silver and gold clusters at defect centers of MgO
Authors: Bürgel Christian , Mitrić Roland , Bonačić‐Koutecký Vlasta 
Published: January 2010

AbstractIn this contribution we present the structural and optical properties of small noble‐metal clusters at the FS‐center defect of the MgO (100) support. We focus on comparing absorption and emission properties of supported silver and gold clusters. It will be shown that the leading absorption features in the low energy regime are similar for supported silver and gold clusters of the same size, in spite of the direct involvement of d electrons from Au atoms due to strong relativistic effects. Molecular dynamics (MD) simulations in the excited electronic states allow us to unravel relaxation mechanism and to propose the smallest noble‐metal clusters at the FS‐center defect, Ag2,4@F5c and Au2,4@F5c, as good candidates for emissive centers. In contrast, larger supported Ag8@F5c and Au8@F5c clusters are unlikely to fluoresce.
Preparation of NaSi thin films for the guest free Si clathrate thin films by heat resistance apparatus using NaSi target materials
Authors: Narita Tomoki , Ueno Hiroyuki , Baba Tatsuya , Kume Tetsuji , Ban Takayuki , Iida Tamio , Habuchi Hitoe , Natsuhara Hironori , Nonomura Shuichi 
Published: January 2010

AbstractIn order to make a thin film of sodium silicide (NaSi), Na was evaporated onto a Si substrate, and the evaporated Na film was annealed under Ar atmosphere without exposure to the air. The annealing condition with 350 °C for 4 h yielded the XRD patterns characteristics of NaSi, indicating the formation of the NaSi on the Si substrate (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural, optical and thermal studies on PbS nanocubes
Authors: Paul Gouri Sankar , Agarwal Pratima 
Published: January 2010

AbstractWe have synthesized PbS nanocubes by solvothermal process with ethylenediamine (en) solvent for three different reaction times. XRD studies revealed that in all the cases pure PbS phase exists. Surface morphology of these powder samples are studied by SEM and TEM whereas compositional analysis and chemical purity are observed by EDAX. The emission peaks in the UV‐Vis range suggest the band gap of the structure to be much higher compared to bulk counterpart. The structures are found to be stable up to 700 °C and are suitable for high temperature device applications. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Annealing effects on aSiNx grown by PECVD using different gas mixtures
Authors: Mercaldo Lucia V. , Veneri Paola Delli , Esposito Emilia M. , Tucci Mario 
Published: January 2010

AbstractSilicon quantum dots embedded in dielectric matrix have interesting possible applications both in microelectronics and photovoltaics. In most cases the fabrication processes involve sputtering or plasma enhanced chemical vapour deposition (PECVD) followed by a high‐temperature (>1000°C) treatment. The possibility of realizing Si nanostructures in situ or at least reducing the annealing temperature deserves to be explored in view of a more direct and cheaper application. We report on annealing effects (temperature range 600‐1100°C) on silicon nitride films. Si rich samples have been deposited by PECVD at 300°C using two different gas mixtures: silane and nitrogen in one case and silane and ammonia diluted in nitrogen in the other. The evolution of Raman spectra, room temperature photoluminescence, and optical absorption of samples with similar refraction index has been investigated. Evidence of partial phase separation, with silicon‐rich and nitrogen‐rich regions, in the as‐grown material has been inferred, with the thermal treatments inducing further reorganization of the two phases. Crystallization of silicon aggregates has been detected only after the highest temperature treatment on both types of samples, with larger nanocrystals when growing the material from silane and nitrogen. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A new structure of counter electrode used for dye‐sensitized solar cells
Authors: Ji W. W. , Zhang X. D. , Zhao Y. , Yang Z. H. , Cai N. , Wei C. C. , Sun J. , Xiong S. Z. 
Published: January 2010

AbstractA new structure of counter electrode, which was formed by platinum thin film, FTO, glass, and silver thin film or silver nanoparticles, was proposed. As we have known, the design of sunlight utilization in solar cells was very important for enhancing the energy conversion efficiency. Compared with the conventional counter electrode structure (platinum film, FTO and glass), this new structure that coated with a layer of silver or silver nanoparticles on the back side of conductive glass, can obviously make much more use of sunlight and increase the short‐circuit current from 11.60 mA/cm2 to 15.48 mA/cm2. As a result, the energy conversion efficiency of the dye‐sensitized solar cell (DSC) was improved from 4.39% to 6.05% under AM1.5. It was evident that this new structure of counter electrode only utilized the reflectance of silver and had no effect on improving conductance of the counter electrode (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis of NaYF4: Yb, Er nanocrystals and its application in silicon thin film solar cells
Authors: Zhang X. D. , Jin X. , Wang D. F. , Xiong S. Z. , Geng X. H. , Zhao Y. 
Published: January 2010

AbstractUp‐converting material, which can be efficiently excited by near infrared light and emit strong visible light through a process termed ‘up‐conversion fluorescence’, has shown a great potential for application in solar cells. In this paper, sodium yttrium fluoride (NaYF4) up‐converting nanocrystals doped with lanthanide ions (Yb3+ and Er3+) using different disodium ethylenediaminetetraacetate (EDTA) concentrations have been synthesized using hydrothermal method. Up‐converting nanocrystal with hexagonal phase has shown strong up‐conversion fluorescence under 980nm laser excitation compared with cubic phase. In order to realize the application of this kind of up‐converting nanocrystals into amorphous silicon thin film solar cells, an up‐convertor made by solidified mixture of above nanocrystal powder and polydimethylsiloxane (PDMS). The up‐convertor attached on the rear side of p‐i‐n type amorphous silicon thin film solar cells enhanced the short circuit current density under the AM1.5 illumination and thus improved the conversion efficiency of solar cells (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Plasma deposition of p‐i‐n microcrystalline silicon solar cells using a single plasma enhanced chemical vapor deposition chamber: study of the phosphorus contamination
Authors: Wang G. H. , Zhang X. D. , Xu S. Z. , Wei C. C. , Sun J. , Xiong S. Z. , Geng X. H. , Zhao Y. 
Published: January 2010

AbstractA series of microcrystalline silicon thin films were fabricated by very high frequency plasma enhanced chemical vapor deposition in a single‐chamber at different phosphorus‐contamination backgrounds. The influence of phosphorus on the properties of p‐layer was studied. The results of electrical properties showed that the dark conductivity of p‐layer decreased largely because of the influence of phosphorus. Several techniques used to reduce the phosphorus contaminations were investigated: the deposition of p‐layers between cells, hydrogen plasma treatment and deposition of microcrystalline silicon covering layer after n‐layer of the last cell. Their effectiveness was evaluated by means of the improvement of p‐layer properties and cell performance (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)