bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adopting HRM practices and their effectiveness in small firms facing product‐market competition
Authors: Patel Pankaj C. , Cardon Melissa S. 
Published: March 2010

AbstractSmall firms face many challenges in creating a productive workforce given often severe resource constraints and informal organizational structures. This may be particularly problematic in industries with intense product‐market competition. In this study, we focus on the relationship between product‐market competition and labor productivity, particularly as influenced by both adopting human resource management (HRM) practices and having a group culture within the organization. We examine our model using data from 145 UK‐based small‐ and medium‐sized enterprises. Our findings suggest that having a group culture is a key factor in the extent to which HRM practices are adopted, as well as how effective adopting these practices is for increasing labor productivity. © 2010 Wiley Periodicals, Inc.
Aged mice have enhanced endocortical response and normal periosteal response compared with young-adult mice following 1 week of axial tibial compression
Authors: Brodt Michael D , Silva Matthew J 
Published: March 2010

Abstract
With aging, the skeleton may lose its ability to respond to positive mechanical stimuli. We hypothesized that aged mice are less responsive to loading than young-adult mice. We subjected aged (22 months) and young-adult (7 months) BALB/c male mice to daily bouts of axial tibial compression for 1 week and evaluated cortical and trabecular responses using micro–computed tomography (µCT) and dynamic histomorphometry. The right legs of 95 mice were loaded for 60 rest-inserted cycles per day to 8, 10, or 12 N peak force (generating mid-diaphyseal strains of 900 to 1900 µε endocortically and 1400 to 3100 µε periosteally). At the mid-diaphysis, mice from both age groups showed a strong anabolic response on the endocortex (Ec) and periosteum (Ps) [Ec.MS/BS and Ps.MS/BS: loaded (right) versus control (left), p &lt; .05]. Generally, bone formation increased with increasing peak force. At the endocortical surface, contrary to our hypothesis, aged mice had a significantly greater response to loading than young-adult mice (Ec.MS/BS and Ec.BFR/BS: 22 months versus 7 months, p &lt; .001). Responses at the periosteal surface did not differ between age groups (p &gt; .05). The loading-induced increase in bone formation resulted in increased cortical area in both age groups (loaded versus control, p &lt; .05). In contrast to the strong cortical response, loading only weakly stimulated trabecular bone formation. Serial (in vivo) µCT examinations at the proximal metaphysis revealed that loading caused a loss of trabecular bone in 7-month-old mice, whereas it appeared to prevent bone loss in 22-month-old mice. In summary, 1 week of daily tibial compression stimulated a robust endocortical and periosteal bone-formation response at the mid-diaphysis in both young-adult and aged male BALB/c mice. We conclude that aging does not limit the short-term anabolic response of cortical bone to mechanical stimulation in our animal model. © 2010 American Society for Bone and Mineral Research
Proteomic analysis for the anti‐apoptotic effects of cystamine on apoptosis‐prone macrophage
Authors: Kao Shao‐Hsuan , Hsu Tsai‐Ching , Yu Jau‐Song , Chen Jeng‐Ting , Li Sin‐Lun , Lai Wen‐Xian , Tzang Bor‐Show 
Published: March 2010

AbstractIncreased macrophage vulnerability is associated with progression of systemic lupus erythematosus. Our previous studies have shown that cystamine, an inhibitor of transglutaminase 2 (TG2), alleviated the apoptosis of hepatocyte and brain cell in lupus‐prone mice NZB/W‐F1. In present study, we further investigated the effects of cystamine on apoptosis‐prone macrophages (APMs) in the lupus mice. Using two‐dimensional gel electrophoresis (2‐DE) analysis, we found that cystamine induced a differential protein expression pattern of APM as comparing to the PBS control. The protein spots presenting differential level between cystamine and PBS treatment were then identified by peptide‐mass fingerprinting (PMF). After bioinformatic analysis, these identified proteins were found involved in mitochondrial apoptotic pathway, oxidative stress, and mitogen‐activated protein (MAP) kinase‐mediated pathway. Further investigation revealed that cystamine significantly decreased the levels of apoptotic Bax and Apaf‐1 and the activity of caspase‐3, and increased the levels of anti‐apoptotic Bcl‐2 in APM. We also found that these apoptotic mediators were up‐regulated in a correlation with the progression of lupus severity in NZB/W‐F1, which were little affected in BALB/c mice. We also found that the reduced serum glutathione was restored by cystamine in NZB/W‐F1. Interestingly, the phosphorylation of extracellular signal‐regulated kinase 1/2 (ERK1/2) in APM and the phagocytic ability was diminished in presence of cystamine. In conclusion, our findings indicate that cystamine significantly inhibited mitochondrial pathway, induced antioxidant proteins, and diminished phosphorylation of extracellular ERK1/2, which may alleviate the apoptosis and the phagocytic ability of APM. J. Cell. Biochem. 110: 660–670, 2010. © 2010 Wiley‐Liss, Inc.
Raman spectroscopic discrimination of pigments and tempera paint model samples by principal component analysis on first‐derivative spectra
Authors: Navas Natalia , Romero‐Pastor Julia , Manzano Eloisa , Cardell Carolina 
Published: March 2010

AbstractThis work explores the application of principal component analysis (PCA) on first‐derivative Raman spectra to investigate historical tempera paint model samples. Various paint model samples were prepared containing pure blue pigments (azurite, lapis lazuli and smalt), pure red pigments (cinnabar, minium and raw Sienna), pure white pigments (lead white, chalk and gypsum), pure egg yolk as binder and tempera model samples obtained by mixing each of the pigments with the binder, and further characterized by Raman spectroscopy. The corresponding Raman spectra were used to apply PCA in order to test whether spectral differences allowed discrimination of samples based on their composition. Multivariate analyses were performed separately on three data matrices, one for each color, namely, white, blue and red, corresponding to the model samples, and all containing the spectral data of the binder model sample. Different pretreatments, that is log and derivative spectra, were performed on the spectra since no pattern distributions were obtained when the original Raman spectra were analyzed. Nevertheless, the multivariate analysis of the original Raman spectra was able to track alterations of sensitive pigments due to laser interaction. Results showed the excellent ability of PCA, when applied to the derived Raman spectra, to discriminate model samples according to their differing compositions in the three groups of model samples tested. This is the first attempt to use this approach in the field of cultural heritage and demonstrates the potential benefits for identifying historical pigments and binders for purposes of conservation and restoration. Copyright © 2010 John Wiley & Sons, Ltd.
Kinetics and mechanism for the acid‐catalyzed addition of propionic acid to tetradecenes and hexadecenes
Authors: Gee Jeffrey C. , Kurukji Daniel 
Published: March 2010

AbstractWe developed a kinetic model for the reversible direct addition of propionic acid to linear tetradecences and linear hexadecenes on Amberlyst 15 at 93°C. The model addresses concurrent double bond isomerization of the olefins and assumes carbenium ion formations to be rate limiting for all conversions; it is detailed enough to include terms for multiple isomers of esters and olefins. The reaction was first order in olefin and in ester but was one‐half order in propionic acid. Gas chromatography was the analytical method employed to follow the reactions, and this study represents a novel use of this analytical method to elucidate carbenium ion behavior. The model includes five rate‐determining steps and five fast steps. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 354–371, 2010
Block Copolymer‐Templated Synthesis and Organization of Semiconductor Nanocrystals
Authors: Karanikolos G. N. , Alexandridis P. , Mountziaris T. J. 
Published: March 2010

AbstractSummary: Templates formed by the self‐assembly of amphiphilic block copolymers in selective solvents have been found to be instrumental in controlling critical parameters in semiconductor nanomaterials fabrication, including particle size, shape, and composition. These tunable nanoreactors exhibit rich polymorphism and have enabled the synthesis of a variety of nanostructures such as dots, wires, tubes, hollow spheres, and 2‐D structures by growth‐under‐confinement at room temperature. The encapsulated particles have optical and electronic properties that are dependent upon physical dimensions and morphology, and exhibit inherent stability and functionalization flexibility, thus opening up promising prospects through their integration into functional optoelectronic and biological systems.
Synthesis of Poly(Alkyl Cyanoacrylates) as Biodegradable Polymers for Drug Delivery Applications
Authors: Dossi M. , Storti G. , Moscatelli D. 
Published: March 2010

AbstractSummary: Poly(alkyl cyanoacrylates) are biodegradable and biocompatible polymers. Ethyl, n‐butyl and octyl cyanoacrylate have been approved in the last decades by the US Food and Drug Administration (FDA) and novel applications are continuously appearing. Recently, such polymers have been proposed as raw materials for the synthesis of nanoparticles aimed to drug delivery. In the literature, such nanoparticles have been always produced through heterogeneous polymerization processes in water. In this work, the anionic polymerization of ethyl, n‐butyl and octyl‐cyanoacrylate in water is systematically investigated. Optimum conditions for the process are identified by changing reaction temperature and solution pH. It is found that an aqueous dispersion medium at pH around 5 and 65 °C gives the best results in terms of polymer molecular weight for all monomers, even if the process exhibits the dominant production of low molecular weight (LMW) polymer. On the other hand, the amount of high molecular weight polymer becomes noticeable at room temperature.
In Line Monitoring of VAc‐BuA Emulsion Polymerization Reaction in a Continuous Pulsed Sieve Plate Reactor using NIR Spectroscopy
Authors: Chicoma Dennis , Carranza Verónica , Sayer Claudia , Giudici Reinaldo 
Published: March 2010

AbstractSummary: This work deals with the in line and in situ monitoring of the changes in residual monomer concentrations and polymer particle size in the process of emulsion copolymerization of vinyl acetate (VAc) and butyl acrylate (BuA) over the sections of a novel tubular reactor (pulsed sieve plate continuous reactor, PSPC) using NIR spectroscopy. Off‐line measurements (gas chromatographic, gravimetric and dynamic light scattering) were used as reference for the development of the multivariate PLS calibration model. All NIR spectra were on‐line collected with an IFS 28/N Bruker spectrometer using a probe (transflectance mode) immersed into the reaction medium. The calibration model and validation data were analyzed using the OPUS/QUANT software. The results indicated that there exists a good agreement between values from the NIR calibration models and the off‐line reference measured experimental data. Moreover, the on‐line NIR can detect efficiently the occurrence of disturbances during the polymerization reaction, a useful tool for the improving the process safety.
Effect of Stabilizer Concentration, Pressure and Temperature on Polymerization Rate and Molecular Weight Development in RAFT Polymerization of MMA in scCO2
Authors: Jaramillo‐Soto Gabriel , García‐Morán Pedro R. , Vivaldo‐Lima Eduardo 
Published: March 2010

AbstractSummary: An experimental study on the effect of stabilizer concentration, pressure (100 to 500 bar), and temperature (65 to 85 °C) on polymerization rate and molecular weight development in the reversible addition‐fragmentation chain transfer (RAFT) polymerization of methyl methacrylate (MMA) in supercritical carbon dioxide (scCO2) is presented. AIBN was used as initiator, S‐Thiobenzoyl thioglycolic acid as RAFT agent, and Krytox® 257 FSL as stabilizer. It was observed that the polymerization proceeded in a controlled manner. High conversions can be reached in reasonable times. Fairly low polydispersities (around 1.2) are possible if either pressure or temperature are increased, but better results are obtained if the polymerization proceeds at the upper temperature value of 85 °C.
Electrical Properties Investigation in PA12/PANI Composites
Authors: Mezdour Dounia zed , Tabellout Mohamed , Sahli Salah , Fatyeyeva Kateryna 
Published: March 2010

AbstractSummary: Volume conducting PA‐12 based composites powders were chemically prepared by in situ polymerization and aniline doping at room temperature. These kinds of polyamide / PANI composites were investigated regarding their electrical properties. Their ac and dc electrical properties measured in the frequency range of 10−2–107 Hz are reported and the frequency dependence of electrical conductivity was investigated as a function of PANI concentration leading to the determination of the conductivity. The experimental conductivity was found to increase continuously with PANI content and explained by percolation theory with a relatively low percolation threshold of about 0.4 wt.%. The dielectric behavior of various PANI polymer composites has been characterized by the critical frequency ωc (denoting the crossover from the dc plateau of the conductivity to its frequency dependent ac behaviour). Modelling the conductivity behavior versus volume fraction using Slupkowski approach has revealed that the considered parameters are not sufficient to describe the electrical conductivity behavior.
Synthesis of Poly(3,4‐ethylenedioxythiophene) Hollow Spheres in CTAB/DBS — Mixed Surfactant Solutions
Authors: Sui Jing , Zhang Lijuan , Travas‐Sejdic Jadranka , Kilmartin Paul A. 
Published: March 2010

AbstractSummary: Hollow microspheres of PEDOT (poly(3,4‐ethylenedioxythiophene) ranging from 0.5 to 10 µm have been synthesized by chemically oxidative polymerization of EDOT(3,4‐ethylenedioxythiophene) using ammonium persulfate in a catanionic surfactant solution obtained by mixing cetyltrimethylammonium bromide (CTAB) and sodium dodecylbenzenesulfonate (SDBS). The effect of the molar ratio of CTAB to SDBS on the morphology of the PEDOT oxidation products has been investigated using SEM and TEM and by an analysis of the structural properties using UV‐visible, FTIR and Raman spectroscopies, elemental analysis and conductivity measurements. The electro‐catalytic activity of PEDOT hollow microspheres for the oxidation of ascorbic acid was investigated by cyclic voltammetry in a pH 6 citrate/phosphate buffer solution and compared to the activity of granular PEDOT particles formed in the absence of the catanionic surfactant.
Effect of Phosphorus‐Nitrogen Intumescent Flame Retardant on Structure and Properties of Poly(propylene)
Authors: Vuillequez A. , Lebrun M. , Ion R.M. , Youssef B. 
Published: March 2010

AbstractSummary: Phosphorus‐nitrogen intumescent product (R2000) was filled into polypropylene (PP) as a flame retardant. The neat PP and flame‐retarded PP blends were studied for their structural and mechanical properties after verification of the flame retardancy character of blends. In this paper, the influence of incorporation of different amount (5%, 10%, 15%, 20%, and 25%) of R2000 was studied. The flame retardancy is evaluated by limiting oxygen index (LOI) value, which is enhanced from 17.5 for pure PP to 22.7 for the blend comprising 15% intumescent product, phosphorus‐nitrogen based (R2000). The thermal degradation behaviour of the PP/R2000 blends was investigated using thermogravimetric analysis (TGA) under nitrogen (N2) and oxygen (O2) atmospheres. The influence of the R2000 on the PP crystallization was examined by X‐ray diffraction (XRD) and differential scanning calorimetry (DSC). Further, the mechanical properties of the materials were studied by dynamic mechanical analysis (DMA). The incorporation of the flame retardant had no effect on the crystallization of the neat polymer and the mechanical properties of the materials remained unaffected.
Microindentation Hardness of Nanostructured Thermoplastic Materials
Authors: Adhikari Rameshwar , Khatri Shiva K. , Adhikari Santosh , Michler Goerg H. , Calleja Francisco J. Balta 
Published: March 2010

AbstractSummary:The micromechanical behaviour of various thermoplastics based nanocomposites was investigated with the aid of the microindentation technique. The materials studied were microphase separated styrene‐butadiene block copolymer systems and several thermoplastics reinforced with nano‐sized fillers having variable dimensionality. It was found that the microhardness behaviour of the nanocomposites studied was strongly influenced by the dimensionalities of the filler. Due to large surface to volume‐ratio one‐ and two‐dimensional fillers exhibit a far better reinforcing behaviour than the three dimensional ones. In case of nanostructured block copolymers, the microhardness is not determined by the total polystyrene (PS)/polybutadiene (PB) composition alone but diminishes gradually in presence of freely standing dangling polybutadiene chains even if the morphology of the systems remains unaltered.
A dual mortar approach for 3D finite deformation contact with consistent linearization
Authors: Popp Alexander , Gitterle Markus , Gee Michael W. , Wall Wolfgang A. 
Published: March 2010

AbstractIn this paper, an approach for three‐dimensional frictionless contact based on a dual mortar formulation and using a primal–dual active set strategy for direct constraint enforcement is presented. We focus on linear shape functions, but briefly address higher order interpolation as well. The study builds on previous work by the authors for two‐dimensional problems. First and foremost, the ideas of a consistently linearized dual mortar scheme and of an interpretation of the active set search as a semi‐smooth Newton method are extended to the 3D case. This allows for solving all types of nonlinearities (i.e. geometrical, material and contact) within one single Newton scheme. Owing to the dual Lagrange multiplier approach employed, this advantage is not accompanied by an undesirable increase in system size as the Lagrange multipliers can be condensed from the global system of equations. Moreover, it is pointed out that the presented method does not make use of any regularization of contact constraints. Numerical examples illustrate the efficiency of our method and the high quality of results in 3D finite deformation contact analysis. Copyright © 2010 John Wiley & Sons, Ltd.
Least‐square‐based radial basis collocation method for solving inverse problems of Laplace equation from noisy data
Authors: Mao Xian‐Zhong , Li Zi 
Published: March 2010

AbstractThe inverse problem of 2D Laplace equation involves an estimation of unknown boundary values or the locations of boundary shape from noisy observations on over‐specified boundary or internal data points. The application of radial basis collocation method (RBCM), one of meshless and non‐iterative numerical schemes, directly induces this inverse boundary value problem (IBVP) to a single‐step solution of a system of linear algebraic equations in which the coefficients matrix is inherently ill‐conditioned. In order to solve the unstable problem observed in the conventional RBCM, an effective procedure that builds an over‐determined linear system and combines with least‐square technique is proposed to restore the stability of the solution in this paper. The present work investigates three examples of IBVPs using over‐specified boundary conditions or internal data with simulated noise and obtains stable and accurate results. It underlies that least‐square‐based radial basis collocation method (LS‐RBCM) poses a significant advantage of good stability against large noise levels compared with the conventional RBCM. Copyright © 2010 John Wiley & Sons, Ltd.
Chemical synthesis and characterization of wild‐type and biotinylated N‐terminal domain 1–64 of β2‐glycoprotein I
Authors: Pozzi Nicola , Banzato Alessandra , Bettin Samuele , Bison Elisa , Pengo Vittorio , De Filippis Vincenzo 
Published: March 2010

AbstractThe antiphospholipid syndrome (APS) is a severe autoimmune disease associated with recurrent thrombosis and fetal loss and characterized by the presence of circulating autoantibodies (aAbs) mainly recognizing the N‐terminal domain (DmI) of β2‐glycoprotein I (β2GpI). To possibly block anti‐β2GpI Abs activity, we synthesized the entire DmI comprising residues 1–64 of β2GpI by chemical methods. Oxidative disulfide renaturation of DmI was achieved in the presence of reduced and oxidized glutathione. The folded DmI (N‐DmI) was purified by RP‐HPLC, and its chemical identity and correct disulfide pairing (Cys4‐Cys47 and Cys32‐Cys60) were established by enzymatic peptide mass fingerprint analysis. The results of the conformational characterization, conducted by far‐ and near‐UV CD and fluorescence spectroscopy, provided strong evidence for the native‐like structure of DmI, which is also quite resistant to both Gdn‐HCl and thermal denaturation. However, the thermodynamic stability of N‐DmI at 37°C was remarkably low, in agreement with the unfolding energetics of small proteins. Of note, aAbs failed to bind to plates coated with N‐DmI in direct binding experiments. From ELISA competition experiments with plate‐immobilized β2GpI, a mean IC50 value of 8.8 μM could be estimated for N‐DmI, similar to that of the full‐length protein, IC50(β2GpI) = 6.4 μM, whereas the cysteine‐reduced and carboxamidomethylated DmI, RC‐DmI, failed to bind to anti‐β2GpI Abs. The versatility of chemical synthesis was also exploited to produce an N‐terminally biotin‐(PEG)2‐derivative of N‐DmI (Biotin‐N‐DmI) to be possibly used as a new tool in APS diagnosis. Strikingly, Biotin‐N‐DmI loaded onto a streptavidin‐coated plate selectively recognized aAbs from APS patients.
A rapid protein folding assay for the bacterial periplasm
Authors: Mansell Thomas J. , Linderman Stephen W. , Fisher Adam C. , DeLisa Matthew P. 
Published: March 2010

AbstractAn array of genetic screens and selections has been developed for reporting protein folding and solubility in the cytoplasm of living cells. However, there are currently no analogous folding assays for the bacterial periplasm, despite the significance of this compartment for the expression of recombinant proteins, especially those requiring important posttranslational modifications (e.g., disulfide bond formation). Here, we describe an engineered genetic selection for monitoring protein folding in the periplasmic compartment of Escherichia coli cells. In this approach, target proteins are sandwiched between an N‐terminal signal recognition particle (SRP)‐dependent signal peptide and a C‐terminal selectable marker, TEM‐1 β‐lactamase. The resulting chimeras are localized to the periplasmic space via the cotranslational SRP pathway. Using a panel of native and heterologous proteins, we demonstrate that the folding efficiency of various target proteins correlates directly with in vivo β‐lactamase activity and thus resistance to ampicillin. We also show that this reporter is useful for the discovery of extrinsic periplasmic factors (e.g., chaperones) that affect protein folding and for obtaining folding‐enhanced proteins via directed evolution. Collectively, these data demonstrate that our periplasmic folding reporter is a powerful tool for screening and engineering protein folding in a manner that does not require any structural or functional information about the target protein.