bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential Expression of Chemokines, Chemokine Receptors and Proteinases by Foreign Body Giant Cells (FBGCs) and Osteoclasts
Authors: Khan Usman A. , Hashimi Saeed M. , Khan Shershah , Quan Jingjing , Bakr Mahmoud M. , Forwood Mark R. , Morrison Nigel M.
Published: February 2014

Osteoclasts and foreign body giant cells (FBGCs) are both derived from the fusion of macropahges. These cells are seen in close proximity during foreign body reactions, therefore it was assumed that they might interact with each other. The aim was to identify important genes that are expressed by osteoclasts and FBGCs which can be used to understand peri‐implantitis and predict the relationship of these cells during foreign body reactions. Bone marrow macrophages (BMM) were treated with receptor activator of nuclear factor kappa B ligand (RANKL) to produce osteoclasts. Quantitative PCR (qPCR) was used to identify the genes that were expressed by osteoclasts and FBGCs compared to macrophage controls. TRAP staining was used to visualise the cells while gelatine zymography and western blots were used for protein expression. Tartrate‐resistant acid phosphatase (TRAP), matrix metallo proteinase 9 (MMP9), nuclear factor of activated T cells 1 (NFATc1), cathepsin K (CTSK) and RANK were significantly lower in FBGCs compared to osteoclasts. Inflammation specific chemokines such as monocyte chemotactic protein (MCP1 also called CCL2), macrophage inflammatory protein 1 alpha (MIP1α), MIP1β and MIP1γ, and their receptors CCR1, CCR3 and CCR5, were highly expressed by FBGCs. FBGCs were negative for osteoclast specific markers (RANK, NFATc1, CTSK). FBGCs expressed chemokines such as CCL2, 3, 5 and 9 while osteoclasts expressed the receptors for these chemokines i.e. CCR1, 2 and 3. Our findings show that osteoclast specific genes are not expressed by FBGCs and that FBGCs interact with osteoclasts during foreign body reaction through chemokines. J. Cell. Biochem. 115: 1290–1298, 2014. © 2014 Wiley Periodicals, Inc.
Combined Usage of Stem Cells in End‐Stage Heart Failure Therapies
Authors: Wang Xintong , Zachman Angela L. , Haglund Nicholas A. , Maltais Simon , Sung Hak‐Joon
Published: February 2014

Remarkable achievements have been made in the clinical application of mechanical circulatory support and cardiac transplantation for patients with end‐stage heart failure. Despite the successes, complications associated with these therapies continue to drive cardiac regenerative research utilizing stem cell based therapies. Multiple stem cell lineages hold clinical promise for cardiac regeneration—mostly through cellular differentiation, cellular fusion, and paracrine signaling mechanisms. Bone marrow‐derived endothelial progenitor cells are among the most intriguing and controversial cell types currently being investigated. Formidable barriers exist, however, in finding the ideal cardiac regenerative stem cell, such as identifying specific lineage markers, optimizing in vitro cellular expansion and improving methods of stem cell delivery. Hybrid approaches of cardiac regeneration using stem cell therapies in conjunction with immunomodulation after cardiac transplantation or with mechanical circulatory support produce cutting edge stem cell technologies. This review summarizes the current knowledge and therapeutic applications of stem cells in patients with end‐stage heart failure, including stem cell therapy after implantation of mechanical circulatory support and cardiac transplantation. J. Cell. Biochem. 115: 1217–1224, 2014. © 2014 Wiley Periodicals, Inc.
A general, recursive, and open‐ended response code
Authors: Ringholm Magnus , Jonsson Dan , Ruud Kenneth
Published: February 2014

We present a new implementation of a recent open‐ended response theory formulation for time‐ and perturbation‐dependent basis sets (Thorvaldsen et al., J. Chem. Phys. 2008, 129, 214108) at the Hartree–Fock and density functional levels of theory. A novel feature of the new implementation is the use of recursive programming techniques, making it possible to write highly compact code for the analytic calculation of any response property at any valid choice of rule for the order of perturbation at which to include perturbed density matrices. The formalism is expressed in terms of the density matrix in the atomic orbital basis, allowing the recursive scheme presented here to be used in linear‐scaling formulations of response theory as well as with two‐ and four‐component relativistic wave functions. To demonstrate the new code, we present calculations of the third geometrical derivatives of the frequency‐dependent second hyperpolarizability for HSOH at the Hartree–Fock level of theory, a seventh‐order energy derivative involving basis sets that are both time and perturbation dependent. © 2014 Wiley Periodicals, Inc.
Non‐Cell Autonomous or Secretory Tumor Suppression
Authors: Chua Christelle En Lin , Chan Shu Ning , Tang Bor Luen
Published: February 2014

Many malignancies result from deletions or loss‐of‐function mutations in one or more tumor suppressor genes, the products of which curb unrestrained growth or induce cell death in those with dysregulated proliferative capacities. Most tumor suppressors act in a cell autonomous manner, and only very few proteins are shown to exert a non‐cell autonomous tumor suppressor function on other cells. Examples of these include members of the secreted frizzled‐related protein (SFRP) family and the secreted protein acidic and rich in cysteine (SPARC)‐related proteins. Very recent findings have, however, considerably expanded our appreciation of non‐cell autonomous tumor suppressor functions. Broadly, this may occur in two ways. Intracellular tumor suppressor proteins within cells could in principle inhibit aberrant growth of neighboring cells by conditioning an antitumor microenvironment through secreted factors. This is demonstrated by an apparent non‐cell autonomous tumor suppressing property of p53. On the other hand, a tumor suppressor produced by a cell may be secreted extracellularly, and taken up by another cell with its activity intact. Intriguingly, this has been recently shown to occur for the phosphatase and tensin homolog (PTEN) by both conventional and unconventional modes of secretion. These recent findings would aid the development of therapeutic strategies that seek to reinstate tumor suppression activity in therapeutically recalcitrant tumor cells, which have lost it in the first place. J. Cell. Physiol. 229: 1346–1352, 2014. © 2014 Wiley Periodicals, Inc.
Positive clinical response to clopidogrel is independent of paraoxonase 1 Q192R and CYP2C19 genetic variants
Authors: Martínez‐Quintana Efrén , Medina‐Gil José M , Rodríguez‐González Fayna , Garay‐Sánchez Paloma , Limiñana José M , Saavedra Pedro , Tugores Antonio
Published: February 2014

There is increasing controversy about the influence of serum paraoxonase type 1 and cytochrome CYP2C19 in the conversion of clopidogrel to its pharmaceutically active metabolite. The effect of concomitant medication with the proton pump inhibitor omeprazole has been also subject of intense scrutiny.

We present a cohort of 263 patients receiving anti‐platelet aggregation treatment with clopidogrel and aspirin for 1 year. The paraoxonase 1 gene Q192R variant along with the presence of CYP2C19*2 and *3 loss of function alleles, concomitant medication with proton pump inhibitors and known cardiovascular risk factors were examined to determine their influence in disease relapse due to an ischaemic event during the 12 month treatment period.

The low number of patients suffering a relapse (20 out of 263), indicates that double anti‐aggregation therapy with aspirin and clopidogrel was very effective in our patients. Among the relapsers, evidence of coronary heart disease was the most influencial factor affecting response to therapy, while the presence of the paraoxonase 1 Q192R variant, loss of function of CYP2C19, and concomitant medication with omeprazole were non‐significant.
Comparative structural morphometry and elemental composition of three marine sponges from Western Coast of India
Authors: Kumar Maushmi S. , Shah Bhaumik
Published: February 2014

Three marine sponges Halichondria glabrata, Cliono lobata, and Spirastrella pachyspira from the western coastal region of India were compared for their morphometry, biochemical, and elemental composition. One‐way analysis of variance was applied for spicule morphometry results. Length, width, and length:width ratio were calculated independently. The ratio of length:width varied from 35 to 42 among the grown samples, which remained in the range of 10–22 in young sample at the beginning of studies. However, no significant change was observed in spicule width compared to length. Elemental compositions of marine sponges were determined by field emission gun‐scanning electron microscope. Scanning electron microscopy data revealed that the spicules of all the three sponges were mostly composed of O (47–56%) and Si (30–40%), whereas Al (14.33%) was only detected in the spicules of C. lobata. Apart from these, K, Ni, Ca, Fe, Mg, Na, and S were additionally detected in all the three samples. Presence of heavy metals in the sponges was analyzed by inductively coupled plasma‐atomic emission spectroscopy. Results showed that iron was present in a large amount in samples, followed by zinc, lead, and copper. Microsc. Res. Tech. 77:296–304, 2014. © 2014 Wiley Periodicals, Inc.
Determining sucrose and glucose levels in dual‐purpose sorghum stalks by Fourier transform near infrared (FT‐NIR) spectroscopy
Authors: Chen Shih‐Fang , Danao Mary‐Grace C , Singh Vijay , Brown Patrick J
Published: February 2014

BACKGROUND

Sorghum is an advanced biomass feedstock from which grain, sugar and stover can be used for biofuel production. Determinations of specific sugar contents in sorghum stalks help to make strategic decisions during plant breeding, processing, storage and optimization of fermentation conditions. In this study, Fourier transform near infrared (FT‐NIR) spectroscopy was used as a relatively fast, low‐cost, high‐throughput assay to predict sucrose and glucose levels in stalks of 40 dwarf grain sorghum inbreds.

RESULTS

The diffuse reflection spectra were pretreated with multiplicative scatter correction (MSC) and first‐derivative Savitzy–Golay (SG‐1). Calibrated models were developed by partial least squares regression (PLSR) analysis. Martens' uncertainty test was used to determine the most effective spectral region. The PLSR model for stalk sucrose content was built on 380 significant wavenumbers in the 4000–6999 cm−1 range. The model was based on four factors and had RPD = 2.40, RMSEP = 1.77 and R2 = 0.81. Similarly, the model for stalk glucose was built using 4000–9000 cm−1 and six factors, with RPD = 2.45, RMSEP = 0.73 and R2 = 0.81.

CONCLUSION

PLSR models were developed based on FT‐NIR spectra coupled with multivariate data analysis to provide a quick and low‐cost estimate of specific sugar contents in grain sorghum stalks. This sugar information helps decision making for sorghum‐based biomass processing and storage strategies. © 2014 Society of Chemical Industry
Post‐fledging survival in passerine birds and the value of post‐fledging studies to conservation
Authors: Cox W. Andrew , Thompson Frank R. , Cox Allison S. , Faaborg John
Published: February 2014

Conservation efforts are most effective when we have complete demographic information for a species of concern. Nevertheless, fundamental gaps in our knowledge of demography still exist for many taxa. For passerine birds, the period of time directly after young birds leave the nest and before they disperse and/or migrate (i.e., the post‐fledging period) remains an understudied life stage. We reviewed the literature on survival of passerine birds during the post‐fledging period to synthesize current knowledge on survival rates and the factors affecting these rates, and conducted a sensitivity analysis to explore the relationship between population growth and post‐fledging survival across the range of rates reported in the literature. Fledgling age was a strong predictor of survival, with the highest mortality occurring during the first 3 weeks after birds fledged. Among species, survival ranged from 0.23 to 0.87 during the first 3 weeks post‐fledging and increased with adult body mass and nestling period duration. The relatively high proportion (12 of 19; 63%) of studies that detected at least 1 habitat effect on survival indicates that management focused on post‐fledging habitat can improve survival. Sensitivity analyses indicated that post‐fledging survival rates less than approximately 0.4 require unrealistic overwinter survival rates of juveniles to prevent population decline, unless adult survival rates and seasonal fecundity are high. Post‐fledging survival is a useful metric for monitoring passerine populations because it sets the ceiling on first‐year survival, responds to habitat management, and leads to more comprehensive demographic models for songbirds. © 2014 The Wildlife Society.
Shell‐Crosslinked Hyaluronic Acid Nanogels for Live Monitoring of Hyaluronidase Activity In Vivo
Authors: Kim Jihyun , Chong Youhoon , Mok Hyejung
Published: February 2014

A hyaluronidase (HAdase) has been noticed as a potential drug target as well as prognostic marker because of its close associations with tumor invasion, metastasis, and angiogenesis. Accordingly, precise monitoring of HAdase activity in vivo seems to be crucial not only for the evaluation of HAdase activity but also for non‐invasive molecular imaging. In our study, we propose a new organic, near‐infrared fluorescence imaging probe, indocyanine green (ICG)‐based stimuli‐responsive fluorescence probe for selective imaging of HAdases with appreciable signal‐to‐noise (S/N) ratios in serum and in vivo. Shell‐crosslinked hyaluronic acid (HA) nanogels (sc‐nanogels) are generated via a reducible covalent linkage which incorporate ICG derivatives. The ICG‐embeded HA nanogels via shell‐crosslinking have preferable properties for ideal selective imaging and detection of HAdase activity in vivo. The sc‐nanogels exhibit prominent chemical stability against external light, greatly control background signals in serum, and small size compared to use of self‐assembled ICG‐based carriers. Collapsed ICG in the hydrogel core is selectively disentangled by HAdase treatment for selective near‐infrared imaging without unwanted background signal. The newly designed sc‐nanogels may have great potential to serve as probes for improved selective imaging of HAdase‐associated diseases in clinics as well as HAdase‐activity screening in vivo.
Corrosion of alumina‐forming austenitic steel in molten nitrate salts by gravimetric analysis and impedance spectroscopy
Authors: Fernández A. G. , Rey A. , Lasanta I. , Mato S. , Brady M. P. , Pérez F. J.
Published: February 2014

In recent years, the study of renewable energies and its practical application has increased significantly. Solar energy feasibility entails the development of energy storage systems since solar power plants need to be working in unfavorable weather or night periods. The main heat transfer fluid (HTF) used on these plants is a salt mixture of 60% NaNO3/40% NaNO3 which must be kept above 220 °C to prevent freezing. This high operating temperature causes corrosion problems for steels in contact with the HTF, reducing the lifetime of the solar plants. The present research studies the potential of an alumina‐forming austenitic (AFA) stainless steel (OC‐4, Fe‐25Ni‐14Cr‐3.5Al‐2.5Nb wt% base) as a candidate material for solar plant heat exchangers and pipes. Corrosion behavior of OC‐4, relative to 304 stainless steel and T22 steel, was studied by gravimetric analysis and electrochemical impedance spectroscopy (EIS). The AFA OC‐4 exhibited better corrosion resistance in HTF at 390 °C than the currently used 304 austenitic stainless steel.
Electrochemical investigations on the performance of newly synthesized azomethine polyester on rebar corrosion
Authors: Bhuvaneshwari B. , Selvaraj A. , Iyer N. R. , Ravikumar L.
Published: February 2014

Novel azomethine‐based polyester is synthesized and the structure of the products is confirmed by 1H NMR, FT‐IR, and XRD. The as synthesized polymer is employed as inhibitor against the corrosion of rebar in artificially simulated concrete pore solution with chloride contamination (blank) by means of Tafel polarization and electrochemical impedance measurements. First time in literature, azomethine polyester is employed as inhibitor for rebar corrosion. Polarization studies exhibited the maximum inhibition efficiency of 98% at 1000 ppm concentration. Electrochemical studies revealed the mixed‐type nature of the inhibitors. The adsorption behavior of as synthesized polymeric inhibitor obeys Langmuir adsorption model. Mechanisms reveal the entire molecule is expected to adsorb on to the metal surface with near flat orientation and tend to arrange themselves parallel to each other covering the entire metal surface, hence, preventing the ingress of aggressive species to the metal surface. Further, SEM and atomic force microscope have proven the presence of adsorptive layer on the rebar under the simulated atmosphere.
Pitting corrosion of 13Cr steel in aerated brine completion fluids
Authors: Liu Y. , Xu L. N. , Zhu J. Y. , Meng Y.
Published: February 2014

Corrosion behavior of 13Cr steel in aerated Br−containing brine completion fluids at 150 °C was studied. A series of corrosion tests with different test duration of 7, 15, 30, and 60 days were performed in an autoclave to investigate the corrosion rate, morphology, and pitting evolution. Cross‐sectional morphologies of the corrosion products were observed by scanning electron microscopy (SEM). Energy dispersive spectrum (EDS) was used to study the element distribution of the corrosion product inside the pits. The results showed that 13Cr steel emerged out of slight pitting corrosion, with the pitting growth rate of 0.04 mm/year. The pitting corrosion occurred after corroded 15 days, and the pits were filled with bromide salt. It is deduced that Br was involved in both the breakdown of the passive film and the expansion of the pits.
Corrosion and passivation of the 304 stainless steel in formic acid solutions
Authors: Badea G. E. , Ionita D. , Cret P.
Published: February 2014

Anodic and cathodic potentiostatic polarization curves for 18Cr–10Ni stainless steel electrodes in aqueous formic acid solutions of various concentrations (2.65; 5.3; 10.6; 15.9; and 21.2 M) have been recorded at room temperature in presence and in absence of the dissolved oxygen. The stainless steel is in active state in all tested solutions and passes in the passive state by anodic polarization, presenting an extended region of stable passivity, which shifts to positive potentials domain with the increase of the formic acid concentration. The corrosion and passivation electrochemical parameters were evaluated as function of formic acid concentration. The solution containing 10.6 M HCOOH was the most aggressive for the stainless steel in the active and in the passive state, presenting the maximum values of the corrosion current, critical current of passivation and passive current densities. The corrosion potentials remain in the active state even after 72 h of immersion in the tested formic acid solution and in the presence of dissolved oxygen. The formic acid oxidation takes place indirectly, in the transpasive region of the anodic curves, presenting the high rate in solutions of mean concentrations.
The estimation of corrosion behavior of thermal oxidized TiNbTaZr alloys for biomedical applications
Authors: Mareci D. , Bolat G. , Munteanu C. , Ghiban N. , Cailean A
Published: February 2014

The corrosion behavior of two oxidized TiNbTaZr alloys (Ti25Nb8Ta10Zr and Ti21Nb15Ta6Zr) at 500 and 800 °C for 2‐h in 0.9 wt% NaCl solution are evaluated. Both samples were examined using electrochemical techniques: electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves. The electrochemical corrosion parameters obtained from the EIS and potentiodynamic polarization curves indicated a typical passive behavior for untreated and oxidized TiNbTaZr alloys. EIS studies showed high impedance values for both oxidized samples, increasing with exposure time. The polarization results show excellent corrosion resistance for oxidized TiNbTaZr alloys, corroborated by the low corrosion and anodic current density. The oxidation in air at 500 and 800 °C do not exhibit the susceptibility of localized corrosion processes in 0.9 wt% NaCl solution. In addition, scanning electron microscopy (SEM) was employed to observe the surface morphology after polarization test in 0.9 wt% NaCl solution. The oxidized Ti21Nb15Ta6Zr alloy appears to possess superior corrosion resistance than the oxidized Ti25Nb8Ta10Zr alloy in 0.9 wt% NaCl solution.
Investigation on crystallographic behaviors of nickel‐base single crystal alloy cooling holes with different spanwise injection angles
Authors: Li L. , Wang X. , Ao L. , Zhou Q. , Yue Z.
Published: February 2014

Film cooling as an important thermal protection technology is widely used in aviation and ground gas turbine blades. But film cooling holes reduce the strength of blade seriously, which have become a key region of crack nucleation. In this paper, the plastic behaviors of nickel‐base single crystal alloy turbine cooling holes in spanwise injection angles range from 0° to 40° are investigated on basis of crystallographic constitutive theory. The results show that there are both higher stress regions and lower stress regions around multi‐column cooling holes, where suffer stress interference. The maximum Mises stress occurs at the hole in the center column. The places where the maximum resolved shear stresses occurs change with load and spanwise injection angle. The maximum Mises stress around holes with injection angle of 0° is lowest. With the injection angle increases, the maximum Mises stress increases until injection angles up to 30°. In all the slip systems, the resolved shear stress of hexahedral slip system is most sensitive to the changing of spanwise injection angle and load.
Effects of hot working procedure on surface relief characteristic in an Fe–Mn–Si–Cr shape memory alloy
Authors: Suru M.‐G. , Dan I. , Lohan N. M. , Paraschiv A. L. , Pricop B. , Spiridon I. P. , Baciu C. , Bujoreanu L.‐G.
Published: February 2014

The paper reports the evolution of surface relief and shape memory behavior in an Fe–28Mn–6Si–5Cr (mass%) shape memory alloy (SMA) as a function of the applied hot working procedure. The objective of this paper is to discuss the relationship between surface relief characteristic, structural changes and the type of hot working processing. Particular aspects concerning the relief of martensite plates were reported after the alloy was subjected to two types of hot working procedures, namely hot rolling and hot forging at 1273 K. The observations were performed by means of optical (OM) and atomic force (AFM) microscopy, on bi‐dimensional and three‐dimensional micrographs, corroborated with statistical evaluations. Aiming to reveal the presence of solid phase transitions enabled by hot working, differential scanning calorimetry (DSC) measurements were performed between room temperature and 673 K.
Development of Monopole Interaction Models for Ionic Compounds. Part I: Estimation of Aqueous Henry’s Law Constants for Ions and Gas Phase pKa Values for Acidic Compounds
Authors: Hilal S. H. , Saravanaraj A. N. , Carreira L. A.
Published: February 2014

The SPARC (SPARC Performs Automated Reasoning in Chemistry) physicochemical mechanistic models for neutral compounds have been extended to estimate Henry’s Law Constant (HLC) for charged species by incorporating ionic electrostatic interaction models. Combinations of absolute aqueous pKa values, relative pKa values in the gas phase, and aqueous HLC for neutral compounds have been used to develop monopole interaction models that quantify the energy differences upon moving an ionic solute molecule from the gas phase to the liquid phase. Inter‐molecular interaction energies were factored into mechanistic contributions of monopoles with polarizability, dipole, H‐bonding, and resonance. The monopole ionic models were validated by a wide range of measured gas phase pKa data for 450 acidic compounds. The RMS deviation error and R2 for the OH, SH, CO2H, CH3 and NR2 acidic reaction centers (C) were 16.9 kcal/mol and 0.87, respectively. The calculated HLCs of ions were compared to the HLCs of 142 ions calculated by quantum mechanics. Effects of inter‐molecular interaction of the monopoles with polarizability, dipole, H‐bonding, and resonance on acidity of the solutes in the gas phase are discussed.
Novel effects of rosiglitazone on SMAD2 and SMAD3 signaling in white adipose tissue of diabetic rats
Authors: Beaudoin Marie‐Soleil , Snook Laelie A. , Arkell Alicia M. , Stefanson Amanda , Wan Zhongxiao , Simpson Jeremy A. , Holloway Graham P. , Wright David C.
Published: February 2014

Objective

The effects of the proliferator‐activated receptor gamma (PPARγ) agonist rosiglitazone (ROSI) on the transforming growth factor (TGF)‐β/SMAD signaling pathway in white adipose tissue (WAT) of diabetic rats were assessed.

Methods

Six‐week‐old, male ZDF rats were fed a chow diet with (ZDF ROSI) or without (ZDF chow) ROSI (diet, 100 mg/kg) for 6 weeks. Subcutaneous (scWAT) and retroperitoneal (rpWAT) adipose tissues were excised to quantify the protein content/phosphorylation.

Results

ZDF ROSI animals showed enhanced glucose tolerance and mitochondrial protein content in both depots. The protein content of enzymes involved in fatty acid handling was increased in scWAT of ZDF ROSI animals. ZDF ROSI exhibited decreased phosphorylation of SMAD2 and SMAD3 exclusively in scWAT, along with increases in inhibitory SMAD7 and the E3 ubiquitin ligase SMURF2. In contrast, ROSI increased the protein content of SMAD4, TGF‐β receptor I and II, and SMAD Anchor for Receptor Activation in scWAT.

Conclusions

For the first time, the fact that ROSI inhibits SMAD2 and SMAD3 signaling in a depot‐specific manner in diabetic rats was demonstrated. In scWAT, ROSI reduced SMAD2 and SMAD3 phosphorylation, likely through the inhibitory actions of SMAD7 and SMURF2. Induction of proximal components of the SMAD pathway may constitute a feedback mechanism to counteract ROSI‐induced lipid synthesis in scWAT.
Characterization and modeling of strain rate hardening in natural‐fiber‐reinforced viscoplastic polymer
Authors: Fotouh Ahmed , Wolodko John D. , Lipsett Michael G.
Published: February 2014

The effect of strain rate
on the mechanical properties of short‐hemp‐fiber‐reinforced High Density Polyethylene is characterized and modeled at different values of
and hemp fiber volume fraction (vf) under dry and wet conditions. Based on the experiments, a generalized comprehensive power law model is developed to predict the behavior of the mechanical properties as functions of vf,
, and moisture absorption. It is demonstrated that the developed model successes to accurately simulate the effects of vf,
, and moisture absorption on the mechanical properties of the natural‐fiber‐reinforced composites as well as the unreinforced polymer. POLYM. COMPOS., 35:2290–2296, 2014. © 2014 Society of Plastics Engineers
The OMSSAPercolator: An automated tool to validate OMSSA results
Authors: Wen Bo , Li Guilin , Wright James C. , Du Chaoqin , Feng Qiang , Xu Xun , Choudhary Jyoti S. , Wang Jun
Published: February 2014

Protein identification by MS/MS is an important technique in proteome studies. The Open Mass Spectrometry Search Algorithm (OMSSA) is an open‐source search engine that can be used to identify MS/MS spectra acquired in these experiments. Here, we present a software tool, termed OMSSAPercolator, which interfaces OMSSA with Percolator, a post‐search machine learning method for rescoring database search results. We demonstrate that it outperforms the standard OMSSA scoring scheme, and provides reliable significant measurements. OMSSAPercolator is programmed using JAVA and can be readily used as a standalone tool or integrated into existing data analysis pipelines. OMSSAPercolator is freely available and can be downloaded at http://sourceforge.net/projects/omssapercolator/.
Polymer end group modifications and polymer conjugations via “click” chemistry employing microreactor technology
Authors: Vandenbergh Joke , Tura Tiago , Baeten Evelien , Junkers Tanja
Published: February 2014

This study presents the development of microreactor protocols for the successful continuous flow end group modification of atom transfer radical polymerization precursor polymers into azide end‐capped materials and the subsequent copper‐catalyzed azide alkyne click reactions with alkyne polymers, in flow. By using a microreactor, the reaction speed of the azidation of poly(butyl acrylate), poly(methyl acrylate), and polystyrene can be accelerated from hours to seconds and full end group conversion is obtained. Subsequently, copper‐catalyzed click reactions are executed in a flow reactor at 80 °C. Good coupling efficiencies are observed and various block copolymer combinations are prepared. Furthermore, the flow reaction can be carried out in only 40 min, while a batch procedure takes several hours to reach completion. The results indicate that the use of a continuous flow reactor for end group modifications as well as click reactions has clear benefits towards the development and improvement of well‐defined polymer materials. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1263–1274
Growth of poly(3,4‐ethylenedioxythiophene) films prepared by base‐inhibited vapor phase polymerization
Authors: Metsik Jörgen , Saal Kristjan , Mäeorg Uno , Lõhmus Rünno , Leinberg Silver , Mändar Hugo , Kodu Margus , Timusk Martin
Published: February 2014

Transparent [90% transmittance at 550 nm at a sheet resistance (Rs) of 279 Ω sq−1] poly(3,4‐ethylenedioxythiophene) (PEDOT) films with electrical conductivities up to 1354 S cm−1 are prepared using base‐inhibited vapor phase polymerization at atmospheric pressure. The influence of reaction conditions, such as temperature and growth time, on the film formation is investigated. A simple and convenient two‐electrode method is used for the in situ measurement of resistance, enabling to investigate the growth mechanism of polymer films and the influence of different parameters (relative humidity and the amount of oxidant) on the film growth. Low humidity exerts a detrimental effect on film growth and conductivity. In situ Rs measurements suggest that a large structural change occurs upon washing the PEDOT‐oxidant film. © 2014 Wiley Periodicals, Inc. J Polym Sci Part B: Polym. Phys. 2014, 52, 561–571
Benchmark study on glyphosate‐resistant crop systems in the United States. Economics of herbicide resistance management practices in a 5 year field‐scale study
Authors: Edwards C Blake , Jordan David L , Owen Michael DK , Dixon Philip M , Young Bryan G , Wilson Robert G , Weller Steven C , Shaw David R
Published: February 2014

BACKGROUND

Since the introduction of glyphosate‐resistant (GR) crops, growers have often relied on glyphosate‐only weed control programs. As a result, multiple weeds have evolved resistance to glyphosate. A 5 year study including 156 growers from Illinois, Iowa, Indiana, Nebraska, North Carolina and Mississippi in the United States was conducted to compare crop yields and net returns between grower standard weed management programs (SPs) and programs containing best management practices (BMPs) recommended by university weed scientists. The BMPs were designed to prevent or mitigate/manage evolved herbicide resistance.

RESULTS

Weed management costs were greater for the BMP approach in most situations, but crop yields often increased sufficiently for net returns similar to those of the less expensive SPs. This response was similar across all years, geographical regions, states, crops and tillage systems.

CONCLUSIONS

Herbicide use strategies that include a diversity of herbicide mechanisms of action will increase the long‐term sustainability of glyphosate‐based weed management strategies. Growers can adopt herbicide resistance BMPs with confidence that net returns will not be negatively affected in the short term and contribute to resistance management in the long term. © 2014 Society of Chemical Industry
Template‐assisted Co–Ni alloys and multisegmented nanowires with tuned magnetic anisotropy
Authors: García Javier , Vega Victor , Iglesias Lucia , Prida Victor M. , Hernando Blanca , Barriga‐Castro Enrique D. , Mendoza‐Reséndez Raquel , Luna Carlos , Görlitz Detlef , Nielsch Kornelius
Published: February 2014

Homogeneous Co85Ni15 and Co54Ni46 alloys, together multisegmented Co85Ni15/Co54Ni46 magnetic nanowire arrays have been synthesized by means of potentiostatic and pulsed potentiostatic electrodeposition techniques, respectively, into the pores of hard‐anodic alumina templates. Morphological, compositional and structural characterization indicate that the composition of Co–Ni alloy segments and nanowires can be properly adjusted by varying the electrochemical deposition potential, leading to different crystalline structures (fcc or hcp) depending on the Co–Ni alloy composition. The magnetic properties of homogeneous and multisegmented Co–Ni alloy nanowire arrays, obtained from hysteresis loops and switching field distribution calculations, are correlated with their crystalline structure and effective magnetic anisotropy, to shed light on the magnetization processes that determine the magnetic behaviour of the nanowire arrays.

Part (a) shows a schematic drawing of freestanding multisegmented Co85Ni15/Co54Ni46 nanowires. Part (b) displays the magnetic hysteresis loops of multisegmented nanowire arrays measured along the parallel and perpendicular directions with respect to the nanowires long axis.
Investigation of composites of polymers and Mo6S2I8 nanowires
Authors: Park Ji Hyun , Jo HyeRan , Seong Chae‐Yong , Kim Kyung Ho , Mrzel Ales , Scalia Giusy , Park Yung Woo
Published: February 2014

We have dispersed Mo6S2I8 nanowires in different types of polyvinyl alcohol (PVA), polystyrene sulfonate (PSS) and surfactants, analyzing their effect on the quality of the dispersion. Raman spectroscopy was employed to investigates the nanowires from suspensions as well as in films. I–V characteristics of networks of nanowires, deposited from suspensions stabilized by PSS, were measured as function of temperature, observing, in the linear region, a variable‐range hopping behavior typical of disordered systems.
Accurate calculations of dynamic first hyperpolarizability: Construction of physically justified slater‐type basis sets
Authors: Rossikhin Vladimir , Voronkov Eugene , Okovytyy Sergiy , Sergeieva Tetiana , Kapusta Karina , Leszczynski Jerzy
Published: February 2014

An efficient procedure for construction of physically rationalized Slater‐type basis sets for calculations of dynamic hyperpolarizability is proposed. Their performance is evaluated for the DFT level calculations for model molecules, carried out with a series of functionals. Advantages of new basis sets over standard d‐aug‐cc‐pVTZ and recently developed LPOL‐(FL,FS) Gaussian‐type basis sets are discussed. © 2014 Wiley Periodicals, Inc.
How does the ambiguity of the electronic stress tensor influence its ability to serve as bonding indicator
Authors: Finzel Kati
Published: February 2014

The electronic stress tensor is not uniquely defined. Possible bonding indicators originating from the quantum stress tensor may inherit this ambiguity. Based on a general formula of the stress tensor this ambiguity can be described by an external parameterλfor indicators derived from the scaled trace of the stress tensor (whereby the scaling function is proportional to the Thomas–Fermi kinetic energy density). The influence ofλis analyzed and the consequences for the representation of chemical bonding are discussed in detail. It is found that the scaled trace of the stress tensor may serve as suitable bonding indicator over a wide range ofλvalues, excluding the value range between −0.15 and −0.48. Focusing on the eigenvalues of the stress tensor, it is found that the sign of the eigenvalues heavily depends on the chosen representation of the stress tensor. Therefore, chemical bonding analyses which are based on the interpretation of the eigenvalue sign (e.g., the spindle structure) are strongly dependent on the chosen form of the stress tensor. © 2014 Wiley Periodicals, Inc.
Effective atomic orbitals: A tool for understanding electronic structure of molecules
Authors: Mayer István
Published: February 2014

It is discussed that one can obtain effective atomic orbitals (AOs) in quite different theoretical frameworks of Hilbert‐space and three‐dimensional (3D) analyses. In all cases, one can clearly distinguish between the orbitals of an effective minimal basis set and orbitals which are only insignificantly occupied. This observation makes a solid theoretical basis beyond our qualitative picture of molecular electronic structure, described in terms of minimal basis AOs having decisive participation in bonding, and may be considered as a quantum chemical manifestation of the octet rule. For strongly positive atoms like the hypervalent sulfur, some weakly occupied orbitals reflecting “back donation” can also be identified. From the conceptual point of view, it is very important that AOs of characteristic shape can be obtained even by processing the results of plane wave calculations in which no atom‐centered basis orbitals were applied. The different types of analyses (Hilbert‐space and 3D) can be done on equal footing, performing quite analogous procedures, and they exhibit an unexpected interrelation, too. © 2014 Wiley Periodicals, Inc.
Effects of band offset and doping concentration on the photovoltaic properties of n‐β‐FeSi2/p‐Si and p‐β‐FeSi2/n‐Si heterojunction solar cells
Authors: Xu Jiaxiong , Yang Yuanzheng
Published: February 2014

Semiconducting β‐FeSi2 thin film with high absorption coefficient has been recognized as a novel solar cell material. In this study, the photovoltaic properties of n‐β‐FeSi2/p‐Si and p‐β‐FeSi2/n‐Si heterojunction solar cells with varying band offsets and doping concentrations are analyzed using numerical methods. Calculated results show that changes in electron affinity and doping concentration affect the photovoltaic properties of β‐FeSi2/Si heterojunctions. Two types of effect can be seen in spike‐like band offset, depending on the doping concentrations of β‐FeSi2 and Si. Calculated results can be explained by the band diagrams and photo‐generated carrier collections of β‐FeSi2/Si heterojunctions. To avoid decreased conversion efficiency, low doping concentration of β‐FeSi2 and high doping concentration of Si are favorable. The results of this study can serve as a guide in fabricating β‐FeSi2/Si heterojunction solar cells. Copyright © 2014 John Wiley & Sons, Ltd.
Energy dependence of the energy loss function parametrization of indium in the Drude–Lindhard model
Authors: Pauly N. , Dubus A. , Monier G. , Robert‐Goumet C. , Mahjoub M. A. , Bideux L. , Gruzza B.
Published: February 2014

The energy loss function (ELF) is a key parameter for the calculations of energy losses undergone by electrons in matter. It is often the only input in the calculations performed within the models based on the semi‐classical dielectric response theory. Its perfect knowledge is thus of primordial importance. To evaluate the ELF, it is usual to consider as a model an expansion in Drude–Lindhard (DL) type oscillators with fixed values of the strength, width, energy and dispersion for the various oscillators. However, for materials that are characterized by a single sharp oscillator as aluminium or indium, it has been shown [Phys. Rev. B 46 (1992) 2486] that the damping parameter that corresponds in the DL model to the width of the oscillator increases for decreasing incident electron energy. To emphasize this effect, we perform in this work systematic calculation of the ELF for an indium target and for incident electron energies between 200 and 2000 eV. The ELF is determined by comparing REELS (reflection electron energy loss spectroscopy) experimental inelastic electron scattering cross sections with cross sections calculated within the semi‐classical dielectric response model, which is implemented in the QUEELS‐ε(k,ω)‐REELS software (Quantitative analysis of Electron Energy Losses at Surfaces) [Surf. Interface Anal. 36 (2004) 824]. We also perform measurements and calculations for varying incident and exit angles of the electron, namely for angles to the surface normal between 15o and 75o, to check the validity of our results for all geometries. Our results show that the damping parameter of indium in the DL model for electron energy of 200 eV is three times larger than for energy of 2000 eV. Copyright © 2014 John Wiley & Sons, Ltd.
Neuartige Sanierung der Tragkabel einer Hängebrücke in Norwegen
Authors: Saul Reiner , Nützel Oswald
Published: February 2014

Als Alternative zum herkömmlichen Beschichten von vollverschlossenen Brückenseilen wurde in den letzten Jahren das automatische Umwickeln mit Butylkautschukbändern entwickelt [1]. Dieses Verfahren hat vor allem den Vorteil, dass an die Untergrundvorbereitung weniger strenge Anforderungen gestellt werden müssen als beim Beschichten und der Verkehr weitgehend ungestört bleibt. Bisher wurden hiermit die Einzelseile von drei deutschen Schrägseilbrücken geschützt.

Erstmals wurde das Verfahren jetzt auch zur Sanierung der Tragkabel einer Hängebrücke in Norwegen angewendet. Dabei mussten Lösungen für die spezifischen Gegebenheiten von Hängebrücken – in engem Abstand verlaufende Seile der Tragkabel sowie Anschluss der Hänger und Kabelsattellager – gefunden werden. Als wesentlicher Vorteil erwies sich die Schnelligkeit des Wickelverfahrens: In nur 25 Tagen konnten, trotz einer witterungsbedingten Ausfallzeit von 6 Tagen, 70 % des Gesamtauftrags fertiggestellt werden. Eine Beschichtung wäre bei den klimatischen Verhältnisse nicht – oder nur mit einer sehr aufwendigen Einhausung – möglich gewesen.

Innovative rehabilitation of the main cables of a suspension bridge in Norway. As alternative to the traditional painting of locked coil bridge cables, during the last years the automatic wrapping with butyl rubber tapes has been developed [2]. This procedure has the main advantage, that the preparation of the rope surface needs not to be as accurate as for painting and that the traffic on the bridge remains widely undisturbed. So far it has been applied for the individual cables of three cable stayed bridges in Germany.

Recently, the procedure has been applied for the rehabilitation of the main cables of a suspension bridge in Norway. For this, solutions had to be developed for the specific conditions of a suspension bridge like small distance between the ropes of the main cables and the connection of the hangers and cable saddles. The main advantage of the procedure was its speed: in only 25 days 70 % of the total works were finished – in spite of losing six days by adverse climatic conditions. Under these circumstances, a painting of the cables would have been impossible or would have required expensive, water and air tight protective devices.
Improvement of the physico‐mechanical properties and stability of waste polypropylene in the presence of wood flour and (maleic anhydride)‐grafted polypropylene
Authors: Pal Kaushik , Mukherjee Madhumita , Frackowiak Stanislaw , Kozlowski Marek , Das Chapal K.
Published: February 2014

This paper deals with (maleic anhydride)‐grafted polypropylene (MAH‐g‐PP) and wood flour reinforcement and their effects on the dynamic, mechanical, morphological, and rheological properties of waste polypropylene (PP) composites. MAH‐g‐PP was used as a compatibilizer to improve the physical interaction between the filler and matrix. The composites were prepared by using a twin‐screw extruder followed by injection molding. Thermal stability and mechanical properties of the compatibilized system increased as compared to their values for the uncompatibilized system. Also, nearly 60% and 30% loss was found for mechanical properties and weight loss, respectively, in a biodegradability study. J. VINYL ADDIT. TECHNOL., 20:24–30, 2014. © 2014 Society of Plastics Engineers
Degradability in a natural compost medium of (linear low‐density polyethylene)/(soya powder) blends compatibilized with epoxidized natural rubber
Authors: Sam S.T. , Ismail H.
Published: February 2014

The objective of this study was to investigate the degradability of linear low‐density polyethylene (LLDPE)/(soya powder) blends. The blends were compatibilized by epoxidized natural rubber with 50 mol% of epoxidation. They were exposed to a natural compost medium located in northern Malaysia. The degradability was evaluated by using tensile tests, a morphological study, carbonyl indices, crystallinity measurements, weight loss, and molecular‐weight changes. The tensile strength and elongation at break of the compatibilized blends decreased during one year of exposure. The colonization of fungus and the formation of pores were observed in micrographs. The carbonyl indices, crystallinity, and weight loss increased during exposure, thereby indicating the degradation of the blends. The reduction in molecular weight revealed the degradation of the LLDPE upon composting. Surprisingly, after composting, the compatibilized blends showed more degradation than the uncompatibilized ones. J. VINYL ADDIT. TECHNOL., 20:42–48, 2014. © 2014 Society of Plastics Engineers
Heritability of clubfoot: A twin study
Authors: Engell Vilhelm , Nielsen Jan , Damborg Frank , Kyvik Kirsten Ohm , Thomsen Karsten , Pedersen Niels Wisbech , Andersen Mikkel , Overgaard Søren
Published: February 2014

Introduction

The aetiology of congenital clubfoot is unclear. Although studies on populations, families, and twins suggest a genetic component to the aetiology, other studies have identified environmental factors. The purpose of this study was to calculate heritability in order to determine to what extent genetic and/or environmental factors contribute to the aetiology of congenital clubfoot and to asses whether there was a change in the prevalence over time.

Materials and Methods

The Odense based Danish Twin Registry is unique as it contains data on all the approximately 85,000 twin pairs born in Denmark over the last 140 years. All 46,418 twin individuals born from 1931 through 1982, who had earlier consented to contact, received a 17-page Omnibus questionnaire in the spring of 2002. Data were analysed with structural equation models to identify the best fitting aetiological model based on a balance of goodness-of-fit and parsimony and to estimate heritability.

Results

We found an overall self-reported prevalence of congenital clubfoot of 0.0027 (95 % confidence interval 0.0022–0.0034). Fifty-five complete (both twins answered the question) twin pairs were identified representing 12 monozygotic, 22 same-sex dizygotic, 18 opposite-sex dizygotic, and 3 with unclassified zygosity. The model with only environmental factors (CE) was best fitting based on AIC, and the model with an additive genetic factor (ACE) came in second. Due to the small statistical power, we hypothesise that the model with both genetic and environmental effects (ACE) was the better model. Choosing the ACE-model we found a heritability of clubfoot of 30 %. Regression coefficient for age was −0.002 (−0.011 to 0.005), indicating that there has been no change in prevalence of clubfoot over the 50-year age span we examined.

Discussion

We conclude that non-genetic factors must play a role, and a genetic factor might contribute, in the aetiology of congenital clubfoot.