bluuebunny/crossref_metadata_2025 huggingface dataset:
Rat sciatic nerve repair with a poly‐lactic‐co‐glycolic acid scaffold and nerve growth factor releasing microspheres
Authors: de Boer Ralph , Knight Andrew M. , Borntraeger Andreas , Hébert‐Blouin Marie‐Noëlle , Spinner Robert J. , Malessy Martijn J.A. , Yaszemski Michael J , Windebank Anthony J.
Published: March 2011

The effect of microsphere delivered Nerve Growth Factor (NGF) in a poly‐lactic‐co‐glycolic‐acid (PLGA) 85/15 nerve conduit bridging a 10mm rat sciatic nerve gap was assessed, comparing nine groups (n = 6): PLGA conduits filled with saline, saline and NGF, saline with blank microspheres; four different NGF microspheres (5, 20, 50, and 100 mg/ml); an autologous graft and sciatic nerve gap. Histomorphometry, retrograde tracing, electrophysiology, and functional outcomes were evaluated up to 16 weeks. The autologous graft showed the largest fascicular area (0.65 mm2) and had a significantly greater number of myelinated fibers (P < 0.0001). Electrophysiology showed Compound Muscle Action Potential (CMAP) recordings for the autologous graft returning at 6 weeks after nerve transection, reaching their highest amplitude of 3.6 mV at endpoint. No significant differences were found in functional evaluation between groups or between conduits with microspheres and the saline filled conduit. A PLGA 85/15 nerve conduit is capable of sustaining nerve regeneration. The microsphere delivery system does not interfere with regeneration. © 2011 Wiley‐Liss, Inc. Microsurgery 2011.
Cavity expansion analyses of crushable granular materials with state‐dependent dilatancy
Authors: Jiang M. J. , Sun Y. G.
Published: March 2011

Crushability is one of the important behaviors of granular materials particularly under high stress states, and affects both the deformability and strength of the materials that are in essence associated with state‐dependent dilatancy. In this presentation, first, a new critical state model is proposed to take into account the three different modes of compressive deformation of crushable granular materials, i.e. particle rearrangement, particle crushing and pseudo‐elastic deformation. Second, the governing equations for cavity expansion in crushable granulates are introduced, in which the state‐dependent dilatancy as well as the bounding surface plasticity model are used. Then, the procedure to obtain semi‐analytical solutions to cavity expansion in the material is described in detail, in which a commercial differential equation solver is employed. Finally, cavity expansion analyses are carried out on Toyoura sand, a well‐documented granular material, to demonstrate the effects of crushability and state‐dependent dilatancy. The study shows that particle crushing does occur at both high stress and critical states and affects the stress fields and the deformation behavior of the material surrounding the cavity in association with state‐dependent dilatancy. This leads to conclusion that particle crushing and state‐dependent dilatancy have to be taken into account when cavity expansion theory is used to interpret cone penetration tests and pressuremeter tests. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of periodic fluctuations of micro‐polar boundary conditions on shear localizations in granular soil–structure interaction
Authors: Ebrahimian Babak , Noorzad Asadollah , Alsaleh Mustafa I.
Published: March 2011

In this work, the interface behavior between an infinite extended narrow granular layer and a rough surface of rigid body is investigated numerically, using finite element method in the updated Lagrangian (UL) frame. In this regard, the elasto‐plastic micro‐polar (Cosserat) continuum approach is employed to remove the limitations caused by strain‐softening of materials in the classical continuum. The mechanical properties of cohesionless granular soil are described with Lade's model enhanced by polar terms, including Cosserat rotations, curvatures, and couple stresses. Furthermore, the mean grain diameter as the internal length is incorporated into the constitutive relations accordingly. Here, the evolution and location of shear band, within the granular layer in contact with the rigid body, are mainly focused. In this regard, particular attention is paid to the effects of homogeneous distribution and periodic fluctuation of micro‐polar boundary conditions, prescribed along the interface. Correspondingly, the effects of pressure level, mean grain diameter, and stratified soil are also considered. The finite element results demonstrate that the location and evolution of shear band in the granular soil layer are strongly affected by the non‐uniform micro‐polar boundary conditions, prescribed along the interface. It is found that the shear band is located closer to the boundary with less restriction of grain rotations. Furthermore, the predicted thickness of shear band is larger for higher rotation resistance of soil grains along the interface, larger mean grain diameter, and higher vertical pressure. Regarding the stratified soil, comprising a thin layer with slightly different initial void ratio, the shear band moves towards the layer with initially higher void ratio. Copyright © 2011 John Wiley & Sons, Ltd.
Flexible patch post‐processing recovery strategies for solution enhancement and adaptive mesh refinement
Authors: Carey Varis , Carey Graham F.
Published: March 2011

This study considers local post‐processing strategies on contiguous patches of cells (or elements) and the properties and applications of the resulting approximations. For instance, one is interested in accuracy of recovered gradients and in their use in constructing error estimators or error indicators for adaptivity. Hence, there are two distinct concepts: (1) The improved quality of recovered gradients on a local patch; and/or (2) the use of local recovered quantities to construct error indicators to guide adaptive refinement schemes. We present a framework generalizing existing strategies for averaging operators and discuss the advantages of this framework in a parallel computing environment. Copyright © 2011 John Wiley & Sons, Ltd.
Stress update algorithm for the combined viscoplastic and plastic behaviours of single‐crystal superalloys
Authors: Kindrachuk Vitaliy , Fedelich Bernard
Published: March 2011

A crystallographic constitutive model is developed, which accounts for both rate‐sensitive and rate‐insensitive flow. Single‐crystal plasticity and viscoplasticity are the limiting cases of the model, so that it properly reflects the material response over a wide temperature range. A non‐linear dynamic recovery is included to properly describe ratchetting. We provide a robust integration scheme based on generalization of the return‐mapping algorithm and of the procedure for active set search.

The implicit integration and consistent tangent are implemented through the UMAT subroutine in the ABAQUS finite element program. The capability of the model to account for both high and low strain rates is demonstrated in numerical examples. Finally, the stability of integration scheme and quadratic convergence of the global Newton–Raphson equilibrium iterations are demonstrated on the example of a notched bar under tension. Copyright © 2011 John Wiley & Sons, Ltd.
Liposarcoma in children and young adults: A multi‐institutional experience
Authors: Huh Winston W. , Yuen Carrie , Munsell Mark , Hayes‐Jordan Andrea , Lazar Alexander J. , Patel Shreyaskumar , Wang Wei‐Lien , Barahmani Nadia , Okcu M. Fatih , Hicks John , Debelenko Larisa , Spunt Sheri L.
Published: March 2011

Background

There are limited data regarding the differences in clinical presentation and outcome of liposarcomas between adult and pediatric patients. The role of adjuvant radiotherapy in the treatment of childhood liposarcoma is unclear.

Procedure

A multi‐institutional retrospective analysis of medical records was performed for patients ≤21 years of age presenting with a verified histologic diagnosis of liposarcoma.

Results

Thirty‐three patients were evaluable for this study, 23 of whom were male. Median age was 17.2 years. Twenty‐four cases were myxoid subtype and 7 were pleomorphic subtype. In myxoid cases, 17 (71%) presented with extremity tumors; none had metastases. Eleven of these patients with myxoid subtype were treated with surgery only, seven with surgery + radiation, three with surgery + radiation + chemotherapy. Median radiation therapy dose for patients with myxoid tumors was 60 Gy. At median follow‐up of 4.2 years (range 0.1–32.2 years), two patients relapsed with one death from progressive disease. In seven pleomorphic cases, four patients had primary tumors at central axial sites. Six patients (86%) received multimodal therapy, but six patients experienced relapse of disease. Four patients died from progressive disease.

Conclusions

Pediatric liposarcoma has a different spectrum of presentation compared to adult cases. Myxoid liposarcoma is the more common subtype, usually occurs in extremities, and has an excellent prognosis. Pleomorphic liposarcoma occurs in axial sites, and despite multimodal therapy, outcome is poor. Further study is needed to identify the optimal therapy for pediatric liposarcoma. Pediatr Blood Cancer 2011; 57: 1142–1146. © 2011 Wiley Periodicals, Inc.
Treatment and complications of thalassemia major in Guangxi, Southern China
Authors: Yin Xiao‐Lin , Wu Zhi‐Kui , He Yuan‐Yuan , Zhou Tian‐Hong , Zhou Ya‐Li , Zhang Xin Hua
Published: March 2011

Background

β‐Thalassemia is extremely prevalent in Guangxi province, Southern China. However, little is known about the treatment and complications of patients with thalassemia major (TM) in Guangxi. The first thalassemia center in China was opened in Guangxi in 2003. Since that time, more than 400 patients have been enrolled.

Procedure

From December 2009 to February 2010, data was collected from TM patients visiting the thalassemia center including the circumstances of diagnosis, biological and clinical data, markers of iron overload and treatment.

Results

Data on 231 patients (median age, 5 years; range, 5 months to 21 years) were recorded. Only 44.6% of patients maintained their hemoglobin levels >9.0 g/dl. In 186 patients with ferritin levels >1,000 ng/ml, an iron chelator was used regularly in 44.6%, irregularly in 26.9%, and was not used in 28.5%. The mean serum ferritin level was 3,143 ng/ml and levels increased with age. Height and weight retardation were found in 48.3% and 11.1% patients, respectively. Compared to patients treated outside of the center, patients completing treatment in the thalassemia center had a higher hemoglobin level before transfusion, higher height and weight SD score, and less splenomegaly, but a similar ratio of regular or irregular iron chelation. Six (18.2%) of 33 patients >10 years of age (14.3 ± 2.8 years; range, 11–19 years) were diagnosed as hypothyroid.

Conclusions

Although survival status of patients with TM in Guangxi has improved since the opening of the thalassemia center, TM complications remain high and with an early onset. Pediatr Blood Cancer 2011; 57: 1174–1178. © 2011 Wiley Periodicals, Inc.
Peptide identification quality control
Authors: Vaudel Marc , Burkhart Julia M. , Sickmann Albert , Martens Lennart , Zahedi René P.
Published: March 2011

Identification of large proteomics data sets is routinely performed using sophisticated software tools called search engines. Yet despite the importance of the identification process, its configuration and execution is often performed according to established lab habits, and is mostly unsupervised by detailed quality control. In order to establish easily obtainable quality control criteria that can be broadly applied to the identification process, we here introduce several simple quality control methods. An unbiased quality control of identification parameters will be conducted using target/decoy searches providing significant improvement over identification standards. MASCOT identifications were for instance increased by 13% at a constant level of confidence. The target/decoy approach can however not be universally applied. We therefore also quality control the application of this strategy itself, providing useful and intuitive metrics for evaluating the precision and robustness of the obtained false discovery rate.
A proteomic approach to analysing spheroid formation of two human thyroid cell lines cultured on a random positioning machine
Authors: Pietsch Jessica , Sickmann Albert , Weber Gerhard , Bauer Johann , Egli Marcel , Wildgruber Robert , Infanger Manfred , Grimm Daniela
Published: March 2011

The human cell lines FTC‐133 and CGTH W‐1, both derived from patients with thyroid cancer, assemble to form different types of spheroids when cultured on a random positioning machine. In order to obtain a possible explanation for their distinguishable aggregation behaviour under equal culturing conditions, we evaluated a proteomic analysis emphasising cytoskeletal and membrane‐associated proteins. For this analysis, we treated the cells by ultrasound, which freed up some of the proteins into the supernatant but left some attached to the cell fragments. Both types of proteins were further separated by free‐flow IEF and SDS gel electrophoresis until their identity was determined by MS. The MS data revealed differences between the two cell lines with regard to various structural proteins such as vimentin, tubulins and actin. Interestingly, integrin α‐5 chains, myosin‐10 and filamin B were only found in FTC‐133 cells, while collagen was only detected in CGTH W‐1 cells. These analyses suggest that FTC‐133 cells express surface proteins that bind fibronectin, strengthening the three‐dimensional cell cohesion.
A new versatile peptide‐based size exclusion chromatography platform for global profiling and quantitation of candidate biomarkers in hepatocellular carcinoma specimens
Authors: Lee Hyoung‐Joo , Na Keun , Kwon Min‐Seok , Park Taesung , Kim Kyung Sik , Kim Hoguen , Paik Young‐Ki
Published: March 2011

Disease biomarkers are predicted to be in low abundance; thus, the most crucial step of biomarker discovery is the efficient fractionation of clinical samples into protein sets that define disease stages and/or predict disease development. For this purpose, we developed a new platform that uses peptide‐based size exclusion chromatography (pep‐SEC) to quantify disease biomarker candidates. This new platform has many advantages over previously described biomarker profiling platforms, including short run time, high resolution, and good reproducibility, which make it suitable for large‐scale analysis. We combined this platform with isotope labeling and label‐free methods to identify and quantitate differentially expressed proteins in hepatocellular carcinoma (HCC) tissues. When we combined pep‐SEC with a gas phase fractionation method, which broadens precursor ion selection, the protein coverage was significantly increased, which is critical for the global profiling of HCC specimens. Furthermore, pep‐SEC‐LC‐MS/MS analysis enhanced the detection of low‐abundance proteins (e.g. insulin receptor substrate 2 and carboxylesterase 1) and glycopeptides in HCC plasma. Thus, our pep‐SEC platform is an efficient and versatile pre‐fractionation system for the large‐scale profiling and quantitation of candidate biomarkers in complex disease proteomes.
A systematic analysis of the effects of increasing degrees of serum immunodepletion in terms of depth of coverage and other key aspects in top‐down and bottom‐up proteomic analyses
Authors: Smith Matthew P. Welberry , Wood Steven L. , Zougman Alexandre , Ho Jenny T. C. , Peng Jianhe , Jackson David , Cairns David A. , Lewington Andrew J. P. , Selby Peter J. , Banks Rosamonde E.
Published: March 2011

Immunodepletion of clinical fluids to overcome the dominance by a few very abundant proteins has been explored but studies are few, commonly examining only limited aspects with one analytical platform. We have systematically compared immunodepletion of 6, 14, or 20 proteins using serum from renal transplant patients, analysing reproducibility, depth of coverage, efficiency, and specificity using 2‐D DIGE (‘top‐down’) and LC‐MS/MS (‘bottom‐up’). A progressive increase in protein number (≥2 unique peptides) was found from 159 in unfractionated serum to 301 following 20 protein depletion using a relatively high‐throughput 1‐D‐LC‐MS/MS approach, including known biomarkers and moderate–lower abundance proteins such as NGAL and cytokine/growth factor receptors. On the contrary, readout by 2‐D DIGE demonstrated good reproducibility of immunodepletion, but additional proteins seen tended to be isoforms of existing proteins. Depletion of 14 or 20 proteins followed by LC‐MS/MS showed excellent reproducibility of proteins detected and a significant overlap between columns. Using label‐free analysis, greater run‐to‐run variability was seen with the Prot20 column compared with the MARS14 column (median %CVs of 30.9 versus 18.2%, respectively) and a corresponding wider precision profile for the Prot20. These results illustrate the potential of immunodepletion followed by 1‐D nano‐LC‐LTQ Orbitrap Velos analysis in a moderate through‐put biomarker discovery process.
Differential glomerular proteome analysis of two murine nephropathy models at onset of albuminuria
Authors: Blutke Andreas , Block Carolin , Berendt Frank , Herbach Nadja , Kemter Elisabeth , Amann Kerstin , Fröhlich Thomas , Arnold Georg J. , Wanke Ruediger
Published: March 2011

Purpose: Early stages of various entities of progressive kidney diseases are commonly characterized by development of glomerular hypertrophy and albuminuria. The purpose of the present study was to identify protein biomarker candidates for these glomerular alterations.

Experimental design: Quantitative differences in the glomerular proteomes of two unrelated murine nephropathy models in the defined stage of glomerular hypertrophy at onset of albuminuria were identified by 2‐D DIGE and MALDI‐TOF/TOF analysis. Investigated mouse models were (I): transgenic (tg) mice expressing a dominant negative glucose‐dependent insulinotropic polypeptide receptor (GIPRdn), a model of diabetes mellitus associated nephropathy and (II): growth hormone (GH)‐tg mice, an established model of progressive glomerulosclerosis.

Results: In GIPRdn‐tg mice, nine differentially abundant glomerular proteins were unambiguously identified, and eight in GH‐tg mice (each versus controls). Four proteins (Annexin A4, Dihydropyrimidinase‐related protein 2, Myosin regulatory light chain 2, Tropomyosin 1) displayed a congeneric differential glomerular abundance in both models, thus representing a common differential protein expression profile of glomerular hypertrophy at onset of albuminuria. The glomerular presence of these proteins was also detected in specimen of human focal and segmental glomerulosclerosis and diabetic nephropathy.

Conclusions and clinical relevance: Our findings suggest a pathogenetic relevance of the identified proteins in early stages of chronic kidney diseases and their potential use as diagnostic markers.
Urinary proteomics in cardiovascular disease: Achievements, limits and hopes
Authors: Delles Christian , Diez Javier , Dominiczak Anna F.
Published: March 2011

Cardiovascular disease (CVD) is the major cause of mortality and morbidity worldwide. Diagnosis of CVD and risk stratification of patients with CVD remains challenging despite the availability of a wealth of non‐invasive and invasive tests. Clinical proteomics analyses a large number of peptides and proteins in biofluids. For clinical applications, the urinary proteome appears particularly attractive due to the relative low complexity compared with the plasma proteome and the noninvasive collection of urine. In this article, we review the results from pilot studies into urinary proteomics of coronary artery disease and discuss the potential of urinary proteomics in the context of pathogenesis of CVD.
Using the ISA 84/HAZOP/LOPA procedure to design a safety instrumented system for a fumed silica burner
Authors: Vaughen Bruce K. , Mudd Jeffry O. , Pierce Bryan E.
Published: March 2011

A Cabot team used the ISA 84‐2004 (IEC61511‐1) standard to evaluate the safety instrumented system (SIS) for an existing fumed silica burner and made practical design changes to reduce the control‐related process safety risks. Prior subjective layers of protection reviews and poor definitions for “tolerable risk” had resulted in assigning unreasonably high and impractical safety integrity levels (SIL) on safety critical interlocks. The Team turned to the ISA 84‐approved layers of protection analysis (LOPA) procedure and found it to be a more realistic and a less subjective risk evaluation that resulted in a practical, defensible process safety system design. The Team's procedure focused on the following steps within the SIS life cycle:

Perform a hazard and operability (HAZOP) process hazards analysis (PHA),

Use PHA/HAZOP software to generate LOPA spreadsheets,

Populate the LOPA spreadsheets for each risk scenario and compare the risk levels to the corporate risk matrix,

Design an SIS/SIL to bridge the risk gaps identified using the LOPA, and

Implement and document the changes.

After completing the PHA/LOPA/tolerable risk matrix analysis (Steps 1–3), two scenarios were identified where the process safety risk was marginal and required design improvements. However, the Team struggled with Step 4, the SIS/SIL design, and progress essentially stopped. The Team's key learning, overcoming this roadblock, focused on locating a Certified Functional Safety Expert to complete and verify the SIS/SIL design integrity. Once Step 4 was completed, the Team implemented both identified SIS design improvements (Step 5), reducing the inherent control‐related process safety risks with a practical solution. © 2011 American Institute of Chemical Engineers Process Saf Prog, 2011
Insecticide‐tolerant and plant‐growth‐promoting Rhizobium improves the growth of lentil (Lens esculentus) in insecticide‐stressed soils
Authors: Ahemad Munees , Khan Mohammad S
Published: March 2011

BACKGROUND: Application of insecticides in modern agriculture in order to enhance legume production has led to their accumulation in soils to levels that adversely affect soil microflora such as rhizobia and exert a negative impact on the physiological activities associated with them. This study was therefore designed to identify rhizobial strains expressing higher tolerance to insecticides fipronil and pyriproxyfen and synthesising plant growth regulators even amid insecticide stress.

RESULTS: The fipronil‐ and pyriproxyfen‐tolerant Rhizobium sp. strain MRL3 produced plant‐growth‐promoting substances in substantial amounts, both in the presence and in the absence of the insecticides. In general, both insecticides at recommended and higher rates reduced plant dry biomass, symbiotic properties, nutrient uptake and seed yield of lentil plants. Interestingly, when applied with any concentration of the two insecticides, Rhizobium sp. strain MRL3 significantly increased the measured parameters compared with plants grown in soils treated solely with the same concentration of each insecticide but without inoculant.

CONCLUSION: This study suggests that Rhizobium strain MRL3 may be exploited as a bioinoculant to augment the efficiency of lentil exposed to insecticide‐stressed soils. Copyright © 2010 Society of Chemical Industry
Polarized Raman spectroscopy clarifies the effect of crystal anisotropy on elastic stress fields developed on the surface of silicon single‐crystal
Authors: Porporati Alessandro Alan , Pezzotti Giuseppe
Published: March 2011

We performed polarized/confocal Raman microprobe measurements in order to visualize the effects of crystallographic orientation and anisotropic volume changes on the elastic stress field developed in single‐crystalline silicon upon impinging its surface with a pyramidal indenter. A theoretical analysis of multiaxial stress‐induced phonon scatter was applied and an improved equation proposed for rationalizing the residual (elastic) stress field stored around an indentation print after load removal. The analysis enabled us to attach a physical meaning to an empirical constant (i.e., the volumetric compaction factor), which was originally introduced by other authors for taking into account the effects of volumetric changes at the center of the indentation print. Such a constant has been introduced for highly compressible solids (e.g., some anomalous glasses), but it is found here to play an important role also in silicon. From a more general viewpoint, we clarify here how crystal anisotropy can play a fundamental role in the residual stress fields stored on silicon surfaces.
LiNbO3 thin film for A1 mode of Lamb wave resonators
Authors: Kadota Michio , Ogami Takashi , Yamamoto Kansho , Tochishita Hikari
Published: March 2011

Currently, a high frequency device more than 3 GHz is required. High frequency resonators with resonant frequencies of 4.5 and 6.3 GHz were fabricated by utilizing an anti‐symmetric first mode (A1) of a Lamb wave having a high velocity consisting of a thin LiNbO3 film deposited by a chemical vapor deposition (CVD) system. By measuring polarities of their LiNbO3 films, it was clarified that the thinner film had a large mixture of +c and −c domains, and the occupation ratio of main polarity influenced their frequency characteristics.
Monte Carlo simulation of circular grain growth
Authors: Morón Carlos , Maganto Fernando José , Tremps Enrique , Ramírez Puerto , García Alfonso
Published: March 2011

Monte Carlo simulations have been carried out to study the effect of temperature on the growth kinetics of a circular grain. This work demonstrates the importance of roughening fluctuations on the growth dynamics. Since the effect of thermal fluctuations is stronger in d =2 than in d =3, as predicted by d =3 theories of domain kinetics, the circular domain shrinks linearly with time as A (t)=A(0)‐αt, where A (0) and A(t) are the initial and instantaneous areas, respectively. However, in contrast to d =3, the slope α is strongly temperature dependent for T≥0.6TC. An analytical theory which considers the thermal fluctuations agrees with the T dependence of the Monte Carlo data in this regime, and this model show that these fluctuations are responsible for the strong temperature dependence of the growth rate for d =2. Our results are particularly relevant to the problem of domain growth in surface science. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Organic glasses: cluster structure of the random energy landscape and its effect on charge transport and injection
Authors: Novikov Sergey V.
Published: March 2011

An appropriate model for the random energy landscape in organic glasses is a spatially correlated Gaussian field, generated by randomly located and oriented dipoles and quadrupoles. Correlation properties of energetic disorder directly dictates the mobility dependence on the applied electric field. Electrostatic disorder is significantly modified in the vicinity of the electrode that affects injection properties. Correlated Gaussian field forms clusters. We suggest a simple method to estimate an asymptotics of the cluster distribution on size for deep clusters where a value of the field on each site is much greater than the rms disorder. Hopping transport in organic glasses in the case of high carrier density could be described in terms of the effective density‐dependent temperature. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Is the marginality of non‐reversible heat flow in MDSC experiments a sufficient criterion for self‐organization in network glass‐formers?
Authors: Shpotyuk O. , Kozdras A. , Golovchak R. , Iovu M.
Published: March 2011

Physical ageing caused by 25‐years natural storage is studied in glassy As25S75 by conventional DSC technique. The observed effect was recorded as a significant increase in the value of glass transition temperature and endothermic peak area in the vicinity of glass‐to‐supercooled liquid transition. This result testifies, that marginal values of non‐reversible heat flow in temperature‐modulated DSC (ΔHnr), observed for as‐prepared (or short‐term aged) AsxS100‐x samples within 22.5 < x < 29.5 compositional range [Ping Chen et al 2008 Phys. Rev. B78 224208], can significantly increase after longer period of physical ageing. Owing to these and previous results on collapse of the reversibility window in AsxSe100‐x glasses after long‐term physical ageing, we have concluded that marginality of non‐reversible heat flow is not a sufficient criterion for express identification of the optimally‐constrained self‐organized phases in chalcogenide glasses. To make a conclusion on the marginality of ΔHnr, the long‐term component of physical ageing should be taken into account. A comparison between conventional or temperature‐modulated DSC scans recorded for long‐term aged and rejuvenated glass samples is considered as a suitable criterion for physical ageing in glasses and, therefore, for the possibility of their network to be optimally‐constrained. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of titanium ions on spectroscopic properties of TeO2‐Sb2O3‐B2O3: TiO2 glass ceramics
Authors: Satyanarayana T. , Gandhi Y. , Valente M. A. , Kityk I. V. , Veeraiah N.
Published: March 2011

A family of antimony tellurite glasses of the composition (55‐x)TeO2‐10Sb2O3‐35B2O3 mixed with different concentrations of TiO2 (0 to 2 mol%) were prepared and crystalized. The samples were characterized by XRD and SEM techniques; spectroscopic (optical absorption and Raman) and PIB properties have been investigated. Randomly distributed crystals were identified by SEM. The XRD studies have revealed the presence of Sb2Te2O7, Sb2Te2O9, TiTe3O8,TiBO3 crystalline phases in these samples. The diffraction data also indicated that, the antimony ions coexist in Sb5+ state with Sb3+ state in these samples; however, the concentration of Sb3+ ions seems to be dominant over Sb5+ ions in the samples containing lower concentrations of TiO2. Optical absorption spectral studies have indicated that a considerable proportion of Ti ions do exist in Ti3+ state in addition to Ti4+ state and the redox ratio seems to be increasing with increase in the concentration of TiO2. The Raman spectral studies have revealed the presence of several conventional structural groups viz., TeO4, SbO3, BO3, BO4, TiO4,TiO6 in the glass ceramic network; these studies have also indicated a growing degree of disorder in the glass ceramic with increase in the concentration of TiO2. The experiments on PIB with 7 ns 1064 nm Nd:YAG laser beam indicated the maximum intensity of birefringence for the sample crystallized with 2.0 mol% of TiO2. This result combined with the optical absorption studies allowed us to conclusion that Ti ion surrounding ligands play principal role in the observed PIB effects (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Glass formation in the V2O5‐MoO3‐ZnO system
Authors: Markova‐Velichkova Maya , Iordanova Reni , Dimitriev Yanko
Published: March 2011

Glass formation region in the V2O5‐MoO3‐ZnO system was determined using low cooling rates (102 K/s). The glasses were obtained in the central part of the system from compositions containing 10‐65 mol% V2O5, 10‐65 mol% MoO3 and 10‐50 mol% ZnO. The amorphous and crystalline phases were characterized by x‐ray diffraction (XRD), differential thermal analysis (DTA) and infra‐red spectroscopy (IR). According to DTA data the glass compositions with molar ratio of the components near to 1:1:1 are more stable against crystallization. Structural models for V2O5‐MoO3‐ZnO glasses were suggested on the basis of IR spectral investigation, and by comparing with the data of known crystalline structures. It was established that VO5 groups associated in layers or chains, isolated V2O7 pyrovanadate units and MoO6 groups are the main structural units creating amorphous networks. ZnO depolymerizes vanadate and molybdate amorphous networks (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dielectric and electrical properties investigation of polyamide/polyaniline composite films
Authors: Mezdour Dounia zed , Tabellout Mohamed , Bouanga Christele Vanga , Sahli Salah
Published: March 2011

Surface conductive composites for antistatic purposes consisting of polyamide 6 (PA‐6) polymer films as a matrix containing conductive polyaniline (PANI) particles were chemically elaborated at room temperature by in situ polymerization of aniline inside the matrix. These kind of Polyamide/PANI composites were investigated regarding to their microstuctural and electrical properties. The surface conductivity was characterized using the potential decay technique. The results were correlated with scanning electron microscopic images data concerning PANI particles dispersion in these antistatic polymer films (ASPF). The enhanced surface conductivity was due to percolation of the PANI phase in the surface layer of PA‐6 films. It has been shown by X ray spectra that the crystallinity of the films is also enhanced. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrical, dielectric and structural properties of borovanadate glass systems doped with samarium oxide
Authors: Graça M. P. F. , Fawzy H. , Badr Y. , Elokr M. M. , Nico C. , Soares R. , Costa L. C. , Valente M. A.
Published: March 2011

Glasses doped with rare earth (RE) ions are widely studied due to the numerous applications of these systems (active media for solid state lasers, optical telecommunication, non‐linear optical materials, electro‐optic devices, etc.). Boron trioxide, B2O3, is a known glass forming oxide with a relative low melting temperature. The addition of a transition metal oxide, such as V2O5, promotes the exhibition of semiconducting properties making these promising systems for several technological applications, such that ones involved in solar energy conversion devices. It is known that alkali borovanadate glasses, like alkali borate glasses themselves, are ionically conducting materials. Despite their importance there are only few studies on these glasses reported on literature. Thus, the alkali‐borovanadate glass system constitutes a family with high interest from the electrical and dielectric point of view. The effect of the increment of alkali quantity in the electrical and dielectric response of these glasses and the physical/structural explanation are questions which will be addressed. In this work, the transparent glass samples with molar composition 0.01Sm2O3‐0.99[0.85B2O3‐(0.15‐x)Li2O‐xV2O5] with x = 0, 0.1, 0.2, 0.35, 0.5 and 2 (mol%) were prepared by conventional melting technique. The prepared samples were fully characterized using different experimental techniques such as, differential thermal analysis (DTA), X‐ray diffraction (XRD), electrical and dielectric measurements. The samples structure, electrical and dielectric properties as a function of vanadium ions content was explored and discussed (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The crystallization kinetics of Sb2S3 in (GeS2)0.4(Sb2S3)0.6 glass
Authors: Zmrhalová Zuzana , Málek Jiří , Švadlák Daniel , Barták Jaroslav
Published: March 2011

The crystallization kinetics of antimony trisulphide in (GeS2)0.4(Sb2S3)0.6 glass has been studied by thermomechanical analyzer and microscopy. The linear crystal growth kinetics of Sb2S3 has been observed in the temperature range 293 °C ≤ T ≤ 327.5 °C. The activation energy determined of TMA method (E = 240 ± 5 kJ·mol‐1) is relatively close to the activation energy of crystal growth (EG = 274 ± 7 kJ·mol‐1) from optical microscopy measurements. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of the simulation area on the liquid‐solid phase diagram in molecular dynamics
Authors: Rutkevych P. P. , Wu D. T.
Published: March 2011

In this work we analyze the effects of the fixed size of the simulation box on the properties of liquid‐solid interface in NVT ensemble (constant number of particles, volume, and temperature). Due to spatial constraints implied by the fixed shape of the box the equilibrium parameters like density and pressure of the system depend on the temperature and the region size. Our simulations for a fixed number of crystal planes show that the lattice parameters of the crystal are continuous functions of the simulation box size in the vicinity of the equilibrium box size under the condition of isotropic stress.

While the lattice parameters can be used to determine the box with isotropic stress, doing so requires repetitive simulations and root finding. To resolve the constraints problem, we propose a tilted crystal configuration, that can be used for calculation of bulk properties and is less sensitive to size limitations in NVT ensemble. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Buddlejasaponin IV Induces Cell Cycle Arrest at G2/M Phase and Apoptosis in Immortalized Human Oral Keratinocytes
Authors: Hwang Young Sun , Chung Won‐Yoon , Kim Jin , Park Hee‐Juhn , Kim Eun‐Cheol , Park Kwang‐Kyun
Published: March 2011

Buddlejasaponin IV (BS‐IV), a major component of Pleurospermum kamtschaticum, exerts antiinflammatory and cytotoxic effects against cancer cells. The study investigated whether BS‐IV could prevent oral carcinogenesis by inhibiting the growth of immortalized human oral keratinocytes (IHOKs). BS‐IV reduced cell viability and induced cell cycle arrest at G2/M phase and apoptotic morphological changes in IHOKs. BS‐IV inhibited the levels of cyclin B1, Cdc2 and Cdc25C, but enhanced Chk2 phosphorylation. The increased levels of pRb and p21 protein and the activation of p53 were also noted in BS‐IV‐treated IHOKs. In addition, BS‐IV induced cytochrome c release from mitochondria by reducing antiapoptotic Bcl‐2 levels and increasing pro‐apoptotic Bax levels. BS‐IV treatment resulted in the activation of caspase‐9 and caspase‐3. PARP cleavage was also clearly observed in the BS‐IV‐treated IHOKs. Furthermore, the expression of the Fas death receptor and Fas ligand was induced and procaspase‐8 level was suppressed by BS‐IV treatment. Taken together, BS‐IV treatment inhibited the growth of IHOK cells via the induction of p53‐dependent cell cycle arrest at the G2/M phase and apoptosis via both mitochondrial‐dependent and death receptor‐mediated pathways. Thus, BS‐IV can be considered an excellent candidate for a chemopreventive agent to block the progression of HPV‐induced oral carcinogenesis. Copyright © 2011 John Wiley & Sons, Ltd.
In Vivo Cytokine Modulatory Effects of Cinnamaldehyde, the Major Constituent of Leaf Essential Oil from Cinnamomum osmophloeum Kaneh.
Authors: Lin Shih‐Shen Chou , Lu Tsong‐Ming , Chao Pei‐Chun , Lai Ya‐Yun , Tsai Hsiu‐Ting , Chen Chung‐Shih , Lee Yi‐Pang , Chen Shu‐Chen , Chou Ming‐Chih , Yang Chi‐Chiang
Published: March 2011

The purpose of this study was to analyse the major compound in the leaf essential oil of Cinnamomum osmophloeum Kaneh. and to examine its in vivo toxicity and cytokine‐modulatory effects. The HS‐GC/MS and quantitative HPLC analyses showed the concentrations of the major compounds, cinnamaldehyde, benzaldehyde and 3‐phenylpropionaldehyde, in the leaf essential oil of Cinnamomum osmophloeum to be 16.88, 1.28 and 1.70 mg/mL, respectively. Acute and sub‐acute toxicity tests identified no significant changes in body weight, liver and kidney function indices, and pathology for the mice treated with up to 1 mL/kg body weight of Cinnamomum osmophloeum leaf essential oil or up to 4 mg/kg body weight of cinnamaldehyde. A murine model was established using ovalbumin (OVA)‐primed Balb/C mice treated with various concentrations of Cinnamomum osmophloeum leaf essential oil or cinnamaldehyde daily for 4 weeks. The results of tests with commercial ELISA kits indicated no significant cytokine‐modulatory effects in mice treated with Cinnamomum osmophloeum leaf essential oil; however, the serum concentrations of IL‐2, IL‐4 and IL‐10, but not IFN‐γ, significantly increased in animals treated with 1 mg/kg body weight of cinnamaldehyde during the 4‐week period. The possibility that the other constituents act as antagonists of cinnamaldehyde cannot be excluded. Copyright © 2011 John Wiley & Sons, Ltd.
Emblica officinalis Corrects Functional, Biochemical and Molecular Deficits in Experimental Diabetic Neuropathy by Targeting the Oxido‐nitrosative Stress Mediated Inflammatory Cascade
Authors: Tiwari Vinod , Kuhad Anurag , Chopra Kanwaljit
Published: March 2011

Diabetic neuropathy is one of the most common microvascular complications of diabetes mellitus which affects more than 50% of diabetic patients. Diabetic neuropathic pain is amongst the most difficult types of pain to treat mainly due to the lack of understanding of its etiology and inadequate relief with available drug therapy. The present study targeted oxidative stress mediated nerve damage in diabetic rats using an aqueous extract of Emblica officinalis, a potent natural antioxidant. Diabetic rats exhibited significantly decreased tail‐flick latency in the tail‐immersion test (thermal hyperalgesia) and decreased paw withdrawal threshold in both Randall‐Selitto (mechanical hyperalgesia) and von‐Frey hair test (mechanical allodynia). A decrease in the nociceptive threshold was accompanied by significantly increased oxidative stress, nitrite levels and cytokines (TNF‐α, IL‐1β and TGF‐β1) both in the serum and sciatic nerve of diabetic rats. Treatment with the Emblica officinalis aqueous extract (250, 500 and 1000 mg/kg/day) significantly attenuated all the behavioral, biochemical and molecular alterations in a dose‐dependent manner. The major finding of the study is that insulin alone corrected the hyperglycemia and partially reversed the pain response in diabetic rats. However, combination with Emblica officinalis extract not only attenuated the diabetic condition but also reversed neuropathic pain through modulation of oxidative–nitrosative stress in diabetic rats. Copyright © 2011 John Wiley & Sons, Ltd.
Antiinflammatory Effect of Oldenlandia diffusa and its Constituent, Hentriacontane, through Suppression of Caspase‐1 Activation in Mouse Peritoneal Macrophages
Authors: Kim Su‐Jin , Chung Won‐Seok , Kim Sung‐Soo , Ko Seong‐Gyu , Um Jae‐Young
Published: March 2011

Oldenlandia diffusa (OD) has been used as a natural drug for the treatment of cancer in Asia and specifically in Korea. However, the antiinflammatory mechanisms employed by OD have yet to be completely understood. This study attempted to determine the effects of OD and hentriacontane, one of the constituent compounds of OD, on lipopolysaccharide (LPS)‐induced inflammatory responses in mouse peritoneal macrophages. The findings of this study showed that OD inhibited the production of tumor necrosis factor (TNF)‐α, interleukin (IL)‐6 and prostaglandin E2 (PGE2). The OD inhibited the enhanced levels of cyclooxygenase (COX)‐2 and inducible nitric oxide synthase (iNOS) induced by LPS. It was shown that the antiinflammatory effect of OD occurs via the regulation of the activation of nuclear factor (NF)‐κB and caspase‐1. Moreover, hentriacontane was shown to ameliorate the expression of inflammatory mediators (TNF‐α, IL‐6, PGE2, COX‐2 and iNOS) and the activation of NF‐κB and caspase‐1 in LPS‐stimulated peritoneal macrophages. These results provide novel insights into the pharmacological actions of OD as a potential candidate for the development of new drugs for the treatment of inflammatory diseases. Copyright © 2011 John Wiley & Sons, Ltd.
In Vivo Th1 and Th2 Cytokine Modulation Effects of Rhodiola rosea Standardised Solution and its Major Constituent, Salidroside
Authors: Chou Lin Shih‐Shen , Chin Lengsu William , Chao Pei‐Chun , Lai Ya‐Yun , Lin Long‐Yau , Chou Ming‐Yung , Chou Ming‐Chih , Wei James Cheng‐Chung , Yang Chi‐Chiang
Published: March 2011

Although Rhodiola rosea (L.) is used widely and disseminated in Oriental medicine, its in vivo effects on cytokine modulation remain unclear. Among the biologically active components of Rhodiola rosea, salidroside was suggested to be the most active compound. The objectives of this study were to assess the toxicity and cytokine modulation effects of Rhodiola rosea standardised solution (RRSS) and salidroside. Quantitative high pressure liquid chromatography (HPLC) analysis determined the content of salidroside in RRSS to be 4.39% (w/v). Groups of Balb/c mice were fed daily with different doses of RRSS or salidroside, with CAPE or distilled water used as positive and negative controls, respectively. The acute and subacute toxicity tests did not reveal weight differences, pathological changes, or abnormalities in liver or kidney function indices among the treated groups. Ovalbumin‐primed mouse cytokine assays demonstrated that both T helper (Th1) (IL‐2 and IFN‐γ) and Th2 (IL‐4 and IL‐10) cytokines were significantly increased by feeding with RRSS in a dose‐ and time‐dependent manner (p < 0.05). Moreover, the cytokine modulation effects of salidroside were less prominent than that of RRSS treatment and not dose‐dependent. These findings suggest that increased secretion of both Th1‐ and Th2‐pattern cytokines can be achieved with RRSS and salidroside treatment. Copyright © 2011 John Wiley & Sons, Ltd.
Local geometric algorithm for hole boundary detection in sensor networks
Authors: Shirsat Amit , Bhargava Bharat
Published: March 2011

We present a hole boundary detection algorithm for sensor network which identifies the geographical boundary of voids in the network assuming the relative geographic information of only 2‐hop neighbors. We formalize the fuzzy notion of a hole by relating it to the graph theoretic concept of a chordless cycle enclosing a face in an arrangement of lines. Furthermore, the algorithm for detecting such topological holes is distributed, O(k) per node computation (for k 2‐hop neighbors) and requires synchronization between nodes that are no more than 2‐hops away. The algorithm takes a local best‐effort approach and does not verify if the nodes indeed form a closed polygonal loop. We believe that this local effort is sufficient based on theoretical observations and experiments. In the simulation tests we conducted, this was hardly a restriction in correctly identifying the simple, closed polygonal loops. We discuss the security implications of the hole detection framework in the context of sensor networks. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of theoretical contribution, methodological rigor, and journal quality, on the impact of scale development articles in the field of entrepreneurship
Authors: Kuskova Valentina V. , Podsakoff Nathan P. , Podsakoff Philip M.
Published: March 2011

Despite the widespread belief that empirical studies that are firmly grounded in theory and use valid measures of their focal constructs are more critical to the advancement of science than studies that do not possess these attributes, it is only recently that this belief has begun to be empirically tested. Unfortunately, most of the tests that have been conducted have some limitations. Therefore, the purpose of this study is to examine the effects that an article's theoretical contribution, the rigor of its scale validation procedures, and the quality of the journal in which it is published have on its impact in the field of entrepreneurship. Using expectancy theory as a conceptual framework, we develop and test our hypotheses in a sample of 88 entrepreneurship articles that reported scale development and validation evidence. Our hypotheses were supported in that the results showed that an article's theoretical contribution, methodological rigor, and journal quality significantly predicted the number of citations the article received, even after controlling for article age‐ and author‐related variables. When taken together, the article characteristics and control variables accounted for 66 percent of the variance in article citations. Implications of these findings for researchers in the field of entrepreneurship are discussed. Copyright © 2011 Strategic Management Society.