bluuebunny/crossref_metadata_2025 huggingface dataset:
Sparing strategy does not compromise prognosis in pediatric localized synovial sarcoma: Experience of the International Society of pediatric oncology, malignant mesenchymal tumors (SIOP‐MMT) Working Group
Authors: Orbach Daniel , Dowell Heather Mc , Rey Annie , Bouvet Nathalie , Kelsey Anna , Stevens Mike C
Published: April 2011

Background

The aim of this analysis was to identify if the modified indications of radiotherapy (RT) or radical surgery compromised survival in pediatric synovial sarcoma (SS).

Procedure

Children with non‐metastatic SS, prospectively enrolled in three trials, were analyzed. After primary surgery or biopsy, they received chemotherapy. RT was planned after chemotherapy in patients who had not achieved a complete response (CR). The considered outcome was 5‐year overall survival (OS) and event‐free survival (EFS).

Results

Eighty‐eight patients were identified. Primary tumors were mainly located in limbs (66%). The first‐line therapy for 65 patients was primary resection. Of the 49 patients who had gross tumor resection, 43 received adjuvant chemotherapy, and 8 had RT. All of the 39 patients with macroscopic residual disease received chemotherapy, then only surgery (n = 12) ± RT (n = 22). The 5‐year EFS and OS rates were 68% and 85%, respectively. The TNM stage was a prognostic factor for relapse, whereas primary site of the tumor and TNM stage were prognostic factors for death.

Conclusions

Only 32% of survivors received RT. OS was similar to published data. Omission of RT may be considered in younger children, to limit the potential sequelae in patients with tumors less than 5 cm in size initially submitted to marginal resection. This strategy may also be considered in initially unresected cases, when the tumor is resected at delayed surgery with microscopically free margins, and in patients in complete remission after primary chemotherapy. Pediatr Blood Cancer 2011; 57: 1130–1136. © 2011 Wiley Periodicals, Inc.
Outpatient follow‐up and rehospitalizations for sickle cell disease patients
Authors: Leschke John , Panepinto Julie A. , Nimmer Mark , Hoffmann Raymond G. , Yan Ke , Brousseau David C.
Published: April 2011

Background

Rehospitalization rates are increasingly used as quality indicators for a variety of illnesses, including sickle cell disease. While one small, single center study suggested outpatient follow‐up with a pediatric hematologist was associated with fewer rehospitalizations, no study has examined the effect of post‐discharge outpatient follow‐up on rehospitalization rates across ages and beyond a single site.

Procedure

This is a retrospective cohort study using Wisconsin Medicaid claims data for hospitalized children and adults with sickle cell disease from 2003 to 2007. The primary outcomes were rehospitalization at both 14 and 30 days after an index hospitalization for sickle cell pain crisis (ICD‐9‐CM codes 28242, 28262, 28264, 28269). Univariate survival analyses were performed based on outpatient visit, severe disease, asthma, and age. The Cox proportional hazards model was used for multivariate analyses yielding hazard ratios for the association between outpatient visits and subsequent rehospitalization rates.

Results

Of the 408 patients included, 42 (10.2%) patients were rehospitalized within 14 days and 70 (17.1%) were rehospitalized within 30 days. Multivariate analysis showed that an outpatient visit is associated with lower rates of both 30‐day rehospitalization (Hazard Ratio (HR) 0.442; 95%CI: 0.330–0.593) and 14‐day rehospitalization (HR 0.226; 95%CI: 0.124–0.412), with the majority of 30‐day rehospitalizations occurring within 14 days.

Conclusions

For sickle cell disease, post‐discharge planning should emphasize early follow‐up to prevent subsequent hospitalization and improve care quality. Pediatr Blood Cancer 2012; 58: 406–409. © 2011 Wiley Periodicals, Inc.
Quantitative description of interfacial strength in polypropylene/inorganic particle composites
Authors: Liang Ji‐Zhao
Published: April 2011

The parameters characterizing the interfacial adhesion strength, such as interaction parameter (B) and interfacial adhesion angle (θ), of inorganic particulate‐filled polymer composites were analyzed in this paper. On the basis of the previous studies and the research work reported in literature, several expressions for predicting these parameters and the determination methods of these parameters were proposed, and the relationship between the interaction parameter and interfacial adhesion angle was discussed. Then the parameters B and θ were estimated from the experimental measured tensile strength of the several inorganic particulate‐filled polypropylene (PP) composites including nanometer calcium carbonate, glass bead and diatomite particles. The results showed that the value of θ was about from 44 to 75 degrees while the value of B was varying from 1.12 to 2.42 of these filled systems under the experimental conditions. Moreover, the value of B decreased roughly linearly with increasing θ for these particulate‐filled PP composites.POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Simultaneous Analysis of Multiple Endogenous Plant Hormones in Leaf Tissue of Oilseed Rape by Solid‐phase Extraction Coupled with High‐performance Liquid Chromatography–Electrospray Ionisation Tandem Mass Spectrometry
Authors: Li Yan‐hua , Wei Fang , Dong Xu‐yan , Peng Jin‐hua , Liu Sheng‐yi , Chen Hong
Published: April 2011

Introduction

Plant hormones are important signalling molecules that act at lower concentrations to regulate numerous plant physiological and developmental processes. In order to study the functions of plant hormones, it is necessary to develop a high‐throughput and highly selective and sensitive method for determination of plant hormones.

Objective

Based on SPE‐HPLC‐ESI‐MS/MS method, a highly selective and sensitive method for determination of six plant hormones in leaf tissue of oilseed rape was developed.

Methodology

The extraction was performed with C18 solid‐phase extraction cartridge and the sample was subsequently analysed by HPLC‐ESI‐MS/MS. Methanol and H2O with 0.05% formic acid was selected as the mobile phase for HPLC, using a gradient of increasing methanol content. The plant hormones were quantified in MRM mode and identified in IDA mode by the hybrid triple quadrupole/linear ion trap mass spectrometer with high sensitivity and selectivity.

Results

Under the optimal conditions, good linearities were obtained for six plant hormones with the correlation coefficients above 0.9924. The detection limits of the target compounds were in the range of 0.005–0.2 ng/mL. Reproducibility of the method was obtained with intra‐day and inter‐day relative standard deviations. The extraction recovery yields of plant hormones under SPE conditions ranged from 67.03 to 119.83%. Compared with previous methods, sample preparation time and amount of sample required for analysis of plant hormones were reduced, and more classes of hormones were quantitatively measured. Copyright © 2011 John Wiley & Sons, Ltd.
Characterisation of Galloylated Cyanogenic Glucosides and Hydrolysable Tannins from Leaves of Phyllagathis rotundifolia by LC‐ESI‐MS/MS
Authors: Hooi Poay Tan , Sui Kiong Ling , Cheng Hock Chuah
Published: April 2011

Introduction

Phyllagathis rotundifolia (Jack) Bl. (Melastomataceae) is a creeping herb found in Peninsular Malaysia and Sumatra. Traditionally, a decoction of the leaves is used in the treatment of malaria, fever and stomach ache.

Objective

To provide ESI‐MSn data which are applicable for chemical fingerprinting of P. rotundifolia to obviate laborious isolation and purification steps.

Methodology

The mass spectral data for the compounds isolated from the leaves of P. rotundifolia were obtained by liquid chromatography–electrospray ionisation tandem mass spectrometry.

Results

The MS fragmentation patterns were obtained for galloylated cyanogenic glucosides based on prunasin (prunasin 6′‐O‐gallate 1, prunasin 2′,6′‐di‐O‐gallate 2, prunasin 3′,6′‐di‐O‐gallate 3, prunasin 4′,6′‐di‐O‐gallate 4, prunasin 2′,3′,6′‐tri‐O‐gallate 5, prunasin 3′,4′,6′‐tri‐O‐gallate 6 and prunasin 2′,3′,4′,6′‐tetra‐O‐gallate 7), gallotannins (6‐O‐galloyl‐d‐glucose 8, 3,6‐di‐O‐galloyl‐d‐glucose 9, 1,2,3‐tri‐O‐galloyl‐β‐d‐glucose 10, 1,4,6‐tri‐O‐galloyl‐β‐d‐glucose 11, 3,4,6‐tri‐O‐galloyl‐d‐glucose 12, 1,2,3,6‐tetra‐O‐galloyl‐β‐d‐glucose 13 and 1,2,3,4,6‐penta‐O‐galloyl‐β‐d‐glucose 14), ellagitannins [6‐O‐galloyl‐2,3‐O‐(S)‐hexahydroxy‐diphenoyl‐d‐glucose 15, praecoxin B 16 and pterocarinin C 17], ellagic acid derivatives (3′‐O‐methyl‐3,4‐methylenedioxyellagic acid 4′‐O‐β‐d‐glucopyranoside 18 and 3,3′,4‐tri‐O‐methylellagic acid 4′‐O‐β‐d‐glucopyranoside 19) and gallic acid 20 that were isolated from the leaves of P. rotundifolia.

Conclusion

The ESI‐MSn technique facilitates identification of galloylated cyanogenic glucosides, hydrolysable tannins and ellagic acid derivatives that were isolated from the leaves of P. rotundifolia. It yields MSn spectra that are useful for identification of these compounds in complex samples and permit more complete fingerprinting of plant materials. Copyright © 2011 John Wiley & Sons, Ltd.
Impact of smoking on maternal serum markers and prenatal screening in the first and second trimesters
Authors: Zhang Jing , Lambert‐Messerlian Geralyn , Palomaki Glenn E. , Canick Jacob A.
Published: April 2011

Objectives

To examine the effects of smoking on first and second trimester screening markers and to determine the overall impact of these effects on Down syndrome and trisomy 18 risks in first trimester combined, second trimester quadruple and integrated tests.

Methods

Examination of screening records at Women and Infants Hospital during 2006‐2008. First trimester pregnancy‐associated plasma protein‐A (PAPP‐A), beta‐human chorionic gonadotrophin (hCG) and nuchal translucency and second trimester alpha‐fetoprotein (AFP), unconjugated estriol (uE3), hCG and inhibin A (inhA) multiple of the median (MoM) values were extracted from the database along with risk results, smoking status and relevant demographic information.

Results

Smoking led to significantly reduced median levels of first trimester PAPP‐A (0.89 MoM) and hCG (0.80 MoM), reduced second trimester uE3 (0.96 MoM) and hCG (0.84 MoM), and increased AFP (1.03 MoM) and inhA (1.39 MoM). After accounting for the differences in age between groups, smokers had higher Down syndrome screen positive rates for the second trimester quadruple test, but not for first trimester combined or integrated tests. Screen positive rates for trisomy 18 were markedly increased in smokers relative to age‐matched non‐smokers when using first trimester combined or integrated tests.

Conclusion

Smoking leads to increased screen positive rates, especially for trisomy 18 using combined or integrated tests. Copyright © 2011 John Wiley & Sons, Ltd.
Using FISH to increase the yield and accuracy of karyotypes from spontaneous abortion specimens
Authors: Jobanputra Vaidehi , Esteves Cecilia , Sobrino Antonio , Brown Stephen , Kline Jennie , Warburton Dorothy
Published: April 2011

Objective

Cytogenetic analysis of spontaneous abortions is frequently complicated by culture failure and maternal cell contamination (MCC). The objective of the study is to demonstrate that multiplex fluorescence in situ hybridization (FISH) can increase the yield and accuracy of karyotypes from spontaneous abortion specimens.

Method

A multiplex interphase FISH probe set was used to analyze two sample sets. (1) Uncultured tissues from 153 abortions samples with a normal 46,XX karyotype and (2) a series of 171 samples that either failed to grow or were contaminated. MCC studies were performed on 70 cultures where both karyotype and FISH indicated a normal female karyotype.

Results

FISH showed 31% (53/171) of the specimens karyotyped as 46,XX were either male or abnormal; 23% (40/118) of these specimens were found to have an abnormal chromosome complement. In specimens with culture failure, FISH showed an abnormal complement in 44.4% (68/153). MCC studies showed 41.49% (29/70) cultures of maternal origin, 45.7% (32/70) fetal, 11.4% (8/70) a maternal/fetal mixture and 1 diploid mole.

Conclusion

Results demonstrate the utility of a simple FISH panel in increasing the detection rate of abnormal karyotypes. They also reveal the high frequency of overgrowth of maternal cells in cultured specimens from villi after embryonic loss. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis, characterization, and degradation of biodegradable poly(mannitol citric dicarboxylate) copolyesters
Authors: Pasupuleti Sasikiran , Avadanam Anusha , Madras Giridhar
Published: April 2011

Three groups of poly(mannitol citric dicarboxylate) [p(MCD)] copolyesters were synthesized by catalyst‐free melt condensation of mannitol with acids. The resulting copolyesters were designated as poly(mannitol citric succinate) [p(MCSu)], poly(mannitol citric adipate) [p(MCA)], poly(mannitol citric sebacate) [p(MCS)]. The polymers were characterized by FTIR, 1H NMR, and DSC analysis. The synthesized p(MCD) polymers exhibit glass transition temperatures ranging from 16.5 to 58.5°C. The mechanical, degradation properties, and the drug‐releasing characteristics of these polymers were investigated. It was observed that the mechanical properties of the p(MCD) polymers cover a wide range with Young's modulus of the polymer varying from 12.25 to 660 MPa. Hydrolytic degradation of all polymers was investigated by incubating polymer discs in PBS and the hydrolytic degradation of p(MCD) polymers followed the order, p(MCSu) > p(MCA) > p(MCS). This was attributed to the number of CH2(units in the dicarboxylic monomers. The release of model drug compounds from the p(MCD) polymer discs was also studied. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Nanocomposites based on high impact polystyrene/silver nanoparticles: Effect of silver nanoparticles concentration on the reaction evolution, morphology, and impact strength
Authors: Soriano‐Corral F. , Morales G.
Published: April 2011

Nanocomposites based on high impact polystyrene (HIPS) and silver nanoparticles (AgNPs) were synthesized via in situ bulk‐suspension polymerization adding a colloidal suspension of AgNPs in styrene from the beginning of the reaction. The concentrations of AgNPs in the final nanocomposites were 0, 0.025, 0.10, and 1.0 wt%. The rate of polymerization and free radicals concentration were found to decrease with increasing AgNPs concentration. For nanocomposites with 0.025 and 0.10 wt% of AgNPs, the phenomenon of phase inversion (PI) during the mass polymerization occurred within the same range as that for the blank HIPS. Further, the impact strength of these nanocomposites did not present any changes as compared to the blank HIPS. However, there was no sign of the PI phenomenon in the case of 1.0 wt% of AgNPs, due to a decrease in the amount of free and graft polystyrene onto the rubber chain as the free radicals concentration diminishes with an increase in AgNPs. In this case the impact strength doubles the values of the blank HIPS due to the presence of a interpenetrated polymer network of crosslinked grafted rubber and polystyrene (PS) instead of the formation of a defined morphology. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Synthesis and characterization of sulfone containing main chain oligobenzoxazine precursors
Authors: Altinkok Cagatay , Kiskan Baris , Yagci Yusuf
Published: April 2011

The preparation of soluble and processable polybenzoxazine precursors capable of forming high performance networks is an important field of research with a broad spectrum of application. This study demonstrates an approach that utilizes aromatic sulfonediamine, bisphenol‐A, and formaldehyde in Mannich‐type polycondesation to prepare polybenzoxazine precursor. The structure of the oligomeric precursor (Mn = 2600) was confirmed by FTIR and 1H NMR spectral analysis. The precursor contained both sulfone and benzoxazine ring structures in the backbone. It was shown that small amount of ring‐opened phenolic groups were also present. Thermally activated self‐curing behavior of precursor in the absence of catalyst was studied by differential scanning calorimetry. Thermal properties of the cured polymers were also investigated by thermo gravimetric analysis. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Polypyrrole–polyvinyl alcohol stable nanodispersion: A prospective conducting black ink
Authors: Gangopadhyay Rupali , Molla Mijanur Rahaman
Published: April 2011

Chemical polymerization of pyrrole within aqueous polyvinyl alcohol (PVA) solution gives rise to a nanodispersion with unique stability and monodispersity. The nanodispersion has shown uniform distribution of perfectly spherical ∼110 nm polypyrrole particles (from transmission electron microscopy and dynamic light scattering) with high doping level (from UV‐Vis analysis) and sufficient electrical conductivity (10−3 S/cm). The dispersion with optimum stability and conductivity was subjected to viscoelastic studies. The viscosity of the system was adjusted by dilution with water and shear thinning (under steady shear) was generally observed. Dynamic mechanical studies have shown that the dispersion behaves like a semidiluted polymeric solution that roughly follows the Zimm model of viscoelasticity. This behavior accounts for its unique stability and miscibility with water at any proportion without precipitation. On drying or leaving the sample for 7 days, Fe3+ induced partial crosslinking of PVA chains takes place via –OH groups, although complete gelling does not occur. The dispersion forms flexible and uniform films on glass and metal surfaces that does not dissolve after complete drying; this observation combined with shear thinning encourages its application as ink or paint. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Composition effects of thermoplastic segmented polyurethanes on their nanostructuring kinetics with or without preshear
Authors: Mourier Elise , David Laurent , Alcouffe Pierre , Rochas Cyrille , Méchin Françoise , Fulchiron René
Published: April 2011

In this work, the structuring mechanism from the molten state of various thermoplastic polyurethanes was analyzed with respect to their composition [polyether or polyester soft segments (SSs), aromatic or aliphatic hard segments (HSs)]. As a preliminary study, the molar mass evolution of the materials with the temperature was quantified. Then, based on rheological experiments and in situ rheo‐small angle X‐ray scattering (SAXS) measurements, the structuring was examined at different temperatures and, particularly, the effect of a preshear treatment was analyzed. The temperature effect can be accounted by an Arrhenius‐like law with an activation energy depending mainly on the HS nature. Moreover, the shear induced structuring phenomenon is highlighted for all the studied thermoplastic segmented polyurethanes. Nevertheless, for the studied range of shear treatments, the SAXS analyses did not reveal any specific orientation. Finally, arguments based on the modification of the quench depth (ΔT = TODT − T) by the shear are given to explain the shear induced structuring phenomenon. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Modulating repeat protein stability: The effect of individual helix stability on the collective behavior of the ensemble
Authors: Cortajarena Aitziber L. , Mochrie Simon G. J. , Regan Lynne
Published: April 2011

Repeat proteins are tandem arrays of a small structural motif, in which tertiary structure is stabilized by interactions within a repeat and between neighboring repeats. Several studies have shown that this modular structure is manifest in modular thermodynamic properties. Specifically, the global stability of a repeat protein can be described by simple linear models, considering only two parameters: the stability of the individual repeated units (H) and the coupling interaction between the units (J). If the repeat units are identical, single values of H and J, together with the number of repeated units, is sufficient to completely describe the thermodynamic behavior of any protein within a series. In this work, we demonstrate how the global stability of a repeat protein can be changed, in a predictable fashion, by modifying only the H parameter. Taking a previously characterized series of consensus tetratricopeptide repeats (TPR) (CTPRa) proteins, we introduced mutations into the basic repeating unit, such that the stability of the individual repeat unit was increased, but its interaction with neighboring units was unchanged. In other words, we increased H but kept J constant. We demonstrated that the denaturation curves for a series of such repeat proteins can be fit and additional curves can be predicted by the one‐dimensional Ising model in which only H has changed from the original fit for the CTPRa series. Our results show that we can significantly increase the stability of a repeat protein by rationally increasing the stability of the units (H), whereas the interaction between repeats (J) remains unchanged.
Coarse‐grained modeling of conformational transitions underlying the processive stepping of myosin V dimer along filamentous actin
Authors: Zheng Wenjun
Published: April 2011

To explore the structural basis of processive stepping of myosin V along filamentous actin, we have performed comprehensive modeling of its key conformational states and transitions with an unprecedented residue level of details. We have built structural models for a myosin V monomer complexed with filamentous actin at four biochemical states [adenosine diphosphate (ATP)‐, adenosine diphosphate (ADP)‐phosphate‐, ADP‐bound or nucleotide‐free]. Then we have modeled a myosin V dimer (consisting of lead and rear head) at various two‐head‐bound states with nearly straight lever arms rotated by intramolecular strain. Next, we have performed transition pathway modeling to determine the most favorable sequence of transitions (namely, phosphate release at the lead head followed by ADP release at the rear head, while ADP release at the lead head is inhibited), which underlie the kinetic coordination between the two heads. Finally, we have used transition pathway modeling to reveal the order of structural changes during three key biochemical transitions (phosphate release at the lead head, ADP release and ATP binding at the rear head), which shed lights on the strain‐dependence of the allosterically coupled motions at various stages of myosin V's work cycle. Our modeling results are in agreement with and offer structural insights to many results of kinetic, single‐molecule and structural studies of myosin V. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Application of cycleave PCR to the detection of a point mutation (F167Y) in the β2‐tubulin gene of Fusarium graminearum
Authors: Hou Yiping , Luo Qingquan , Chen Changjun , Zhou Mingguo
Published: April 2011

BACKGROUND: Resistance of Fusarium graminearum to the benzimidazole fungicide carbendazim is caused by point mutations in the β2‐tubulin gene (FGSG_06611.3). The point mutation at codon 167 (TTT → TAT, F167Y) occurs in more than 90% of field isolates in China. It is important to find a suitable method for rapid detection and quantification of this point mutation in the F. graminearum populations.

RESULTS: A pair of primers, Codon167F/Codon167R, were designed to amplify a fragment containing the mutation site, and two cycling probes labelled with different fluorescent reporters were used to detect whether the mutation was present. A cycleave real‐time PCR method was developed for rapid determination of the frequency of this point mutation in 282 F. graminearum perithecia collected from different fields in Jiangsu Province, China. The mutation frequency in ascospores from the perithecia to carbendazim by a spore germination assay was 6.0%, while the frequency of the point mutation at codon 167 by the cycleave real‐time PCR assay was 3.9%.

CONCLUSION: The cycleave real‐time PCR method is suitable for accurate detection of the codon 167 point mutation. The frequency of this mutation in the β2‐tubulin gene represents the resistance frequency in F. graminearum populations to carbendazim. Copyright © 2011 Society of Chemical Industry
Biological control of red rot in sugarcane by native pyoluteorin‐producing Pseudomonas putida strain NH‐50 under field conditions and its potential modes of action
Authors: Hassan Muhammad N , Afghan Shahid , Hafeez Fauzia Y
Published: April 2011

BACKGROUND: Rhizobacteria have a good potential to suppress soilborne diseases, but their efficacy against sugarcane pests is rarely reported. Bacterial strains isolated from the rhizosphere of sugarcane were evaluated for their potential to suppress red rot disease on two susceptible varieties, Co‐1148 and SPF‐234, under field conditions. The strains were also characterised for the production of secondary metabolites associated with their antagonistic activity.

RESULTS: One out of four strains, the Pseudomonas putida strain NH‐50 (EU627168), reduced disease severity by 44–60% in different field trials. This potent antagonistic strain produced pyoluteorin antibiotic, as confirmed by high‐performance liquid chromatography (HPLC). The PltB gene involved in pyoluteorin synthesis was amplified from the P. putida strain NH‐50 and sequenced. The extracellular metabolites and volatile and diffusible antibiotics secreted by the tested strains inhibited mycelial growth of Glomerella tucumensis (Speg.) Arx & E Mull in vitro by 7–55%.

CONCLUSION: The pyoluteorin‐producing bacteria P. putida strain NH‐50 significantly reduced disease severity on both sugarcane varieties, irrespective of fungal inoculation, i.e. either inoculated through stem or through soil. This strain also possesses other plant growth characteristics and can be used as a biopesticide for sugarcane crop. Copyright © 2011 Society of Chemical Industry
Glyphosate‐resistant horseweed made sensitive to glyphosate: low‐temperature suppression of glyphosate vacuolar sequestration revealed by 31P NMR
Authors: Ge Xia , d'Avignon Dana André , Ackerman Joseph JH , Duncan Bill , Spaur Marvin B , Sammons Robert Douglas
Published: April 2011

BACKGROUND: Horseweed has been the most invasive glyphosate‐resistant (GR) weed, spreading to 16 states in the United States and found on five continents. The authors have previously reported that GR horseweed employs rapid vacuolar sequestration of glyphosate, presumably via a tonoplast transporter, substantively to reduce cytosolic glyphosate concentrations.1 It was hypothesized that glyphosate sequestration was the herbicide resistance mechanism. If resistance is indeed endowed by glyphosate sequestration, suppression of sequestration offers the potential for controlling GR horseweed at normal herbicide field‐use rates.

RESULTS: Low‐temperature 31P NMR experiments performed in vivo with GR cold‐acclimated horseweed showed markedly suppressed vacuolar accumulation of glyphosate even 3 days after glyphosate treatment. [In stark contrast, 85% of the visible glyphosate was sequestered 24 h after spraying warm‐acclimated GR horseweed.] Cold‐acclimated GR horseweed treated at normal use rates and maintained at low temperature succumbed to the lethal effects of glyphosate over a 40 day period. Treatment of GR horseweed in the field when temperatures were cooler showed the predicted positive herbicidal response.

CONCLUSIONS: Low temperature markedly diminishes vacuolar sequestration of glyphosate in the GR horseweed biotype, yielding a herbicide response equivalent to that of the sensitive biotype. This supports the recent hypothesis1 that glyphosate sequestration is the resistance mechanism employed by GR horseweed. Copyright © 2011 Society of Chemical Industry
Towards an improved understanding of the dynamics of vineyard‐infesting Scaphoideus titanus leafhopper populations for better timing of management activities
Authors: Rigamonti Ivo E , Jermini Mauro , Fuog Daniele , Baumgärtner Johann
Published: April 2011

BACKGROUND: This paper deals with supervised management of Scaphoideus titanus (Homoptera Cicadellidae) and describes a phenology model designed for improving the understanding of the within‐vineyard dynamics and the timing of insect growth regulator (IGR) applications.

RESULTS: The model consists of five components dealing with (a) the beginning of the post‐dormancy development of overwintering eggs, (b) the egg hatching patterns, (c) the duration of first‐instar nymphs, (d) the development and survival of subsequent instars and (e) the stochastic development of cohorts and their passage into the adult stage. Laboratory data permitted the parameterisation of temperature‐dependent development and survival functions. Field data consisting mainly of beating tray catches allowed model parameterisation and validation. The model satisfactorily predicts the dynamics of age structures, the beginning as well as the pattern of egg hatching, the occurrence of the third instar and the emergence of adults.

CONCLUSION: The phenology model is useful for timing IGR applications and for setting up monitoring activities in supervised S. titanus control. The model is an entry point into an adaptive management system, in that real‐time weather and monitoring data are continuously integrated into the model for improving its explanatory and predictive capabilities. Copyright © 2011 Society of Chemical Industry
Electron transport in bulk GaAsN
Authors: Vogiatzis N. , Rorison J.M.
Published: April 2011

We present theoretical results on the steady state characteristics of bulk GaAs1–xNx using the single electron Monte‐Carlo method (x ≤ 0.4%). Two equivalent models are used. The first includes a GaAs band with a strong localized nitrogen resonance. The second model uses the band anti‐crossing model, in which the localized N level interacts with the GaAs band strongly perturbing the conduction band. We obtain two negative differential velocity peaks from the first model which we associate with N scattering and polar optical phonon emission (POPem). From the second model only one peak is obtained associated with POPem. The first model gives very good agreement with experimental low field mobility. We use this model to include additional scattering resonances related with the pair and larger cluster nitrogen states. Further reduction of the mobility and convergence towards the experimental values is observed.
Electrical properties of polycrystalline CaB6 under high pressure and low temperature
Authors: Li Yan , Yang Jie , Cui Xiaoyan , Hu Tingjing , Liu Cailong , Tian Yongjun , Liu Hongwu , Han Yonghao , Gao Chunxiao
Published: April 2011

Carrier behavior of CaB6 powders was investigated by using in situ Hall effect measurement under high pressure and resistivity property was detected under low temperature with microcircuit fabricated on diamond anvil cell. Carrier behavior was analyzed by carrier concentration and Hall coefficient. The variation of defects in the grain boundary region lead the carrier concentration and the Hall coefficient in the decompression process are much lower than that in the compression process. The resistivity depended temperature at various pressures indicated that CaB6 has a typical metallic behavior under high pressure.
Temperature‐dependent study of the Raman A mode of Cu2ZnSnS4 thin films
Authors: Sarswat Prashant K. , Free Michael L. , Tiwari Ashutosh
Published: April 2011

This temperature‐dependent Raman study of kesterite phase Cu2ZnSnS4 (CZTS) thin film was performed over the temperature range 98–378 K. A detailed qualitative analysis showed that the Raman data for the “A” mode of vibration, the strongest peak for kesterite CZTS films, fit very well to a damped harmonic oscillator (DHO) model. This investigation of temperature‐dependent Raman data shows that the observed frequency shift is due to the cumulative effect of thermal expansion and anharmonicity resulting from a 4‐phonon damping process. The temperature dependence of linewidth is also consistent with the above analysis.
Study of electronic and elastic properties of β‐HgS under high pressure via first‐principles calculations
Authors: Xiao‐Cui Yang , Jie Yang , En‐Jie Zhang , Chun‐Xiao Gao
Published: April 2011

An investigation on the electronic and elastic properties of β‐HgS under high pressure was conducted using first‐principles calculations based on density functional theory with the CASTEP code in MS modeling. Our results demonstrate that the sequence of the pressure‐induced phase transition of HgS is from the zinicblende (β‐HgS, space group F43m) to the cinnabar (α‐HgS, space group P3121) to the rocksalt (space group Fm3m) structure. The calculated transition pressures are reported, which are in good agreement with the available experimental results and the previous theoretical data. The pressure effect on the elastic parameters of HgS in the F43m structure is determined theoretically (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
What qualitative research has taught us about occupational stress
Authors: Mazzola Joseph J. , Schonfeld Irvin Sam , Spector Paul E.
Published: April 2011

While many reviews of job stress and the stressor–strain relationship have been conducted, such reviews typically focus exclusively on quantitative data. In the current paper, we review qualitative studies on occupational stress that met two criteria: (1) the studies employed qualitative methods; (2) the stressors, strains and/or coping strategies were grouped into identifiable, higher‐order categories. Results indicated that the nature of the stressors experienced varied by (a) occupation, (b) country, (c) seniority and (d) gender. The review further revealed that organizational constraints, work overload and interpersonal conflict were relatively universal stressors. Anger and annoyance were the most frequently reported psychological strains in the United States and the United Kingdom, while Chinese workers exhibited tension and anxiety and Indian workers exhibited acceptance. Coping strategies also varied by gender, occupation and country. Research on gender differences suggested that, compared to men, women tended to report more interpersonal stressors. Differences in the ways in which the two types of methodologies are applied, as well as their relative strengths and weaknesses, underline the value of qualitative approaches to the study of occupational stress, especially when used in conjunction with quantitative methods in mixed‐methods studies. Copyright © 2011 John Wiley & Sons, Ltd.
Manipulating Wi‐Fi packet traces with WiPal: design and experience
Authors: Claveirole Thomas , de Amorim Marcelo Dias
Published: April 2011

Packet traces are important objects in networking, commonly used in a wide set of applications, including monitoring, troubleshooting, measurements, and validation, to cite a few. Many tools exist to produce and process such traces, but they are often too specific; using them as a basis for creating extended tools is then impractical. Some other tools are generic enough, but exhibit performance issues. This paper reports on our experience designing WiPal, a packet trace manipulation framework with a focus on IEEE 802.11. WiPal is designed for performance and re‐usability, while introducing several novel features compared to previous solutions. Besides presenting how WiPal's original design can benefit packet processing programs, we discuss a number of issues a program designer might encounter when writing packet trace processing software. An evaluation of WiPal shows that, albeit generic, it does not impact performance regarding execution speed. WiPal achieves performance levels observed only with specialized code and outperforms some well‐known packet processing programs. Copyright © 2011 John Wiley & Sons, Ltd.
Fe2MoO4 as a Precursor Material for Mo Alloying in Steel (Part II): Up‐Scaling Test
Authors: Chychko A. , Teng L. , Nzotta M. , Seetharaman S.
Published: April 2011

The Mo yield when using three different alloying mixtures (MoO3 +C; MoO3 +C + FeOx; and MoO3+ C + CaO) was tested both in laboratory experiments (16 g and 0.5 kg scale) and industrial trials (3 ton scale). The alloying is based on in‐situ formation of compounds of Mo in the mixtures from molybdenite concentrate with industrial grade Fe2O3. Thermogravimetry (TGA) and X‐ray diffraction (XRD) analyses were performed to identify the reduction steps and final products of the alloying mixtures. At least two steps of mass change were discovered during the reduction of all tested mixtures by carbon. The Mo yield for MoO3 + C mixture is 93% which was confirmed by both laboratory and industrial experiments. The Mo yield for MoO3 + C + CaO mixture is around 92% during 16 g scale laboratory and 3 ton scale industrial tests. The best results were obtained in the case of the mixture which contained FeOx, MoO3 and C, resulting in the Mo yield up to 98% at all the experiment scale levels. It was found that the combination of both lower evaporation and fast reduction by carbon of the mixture along with further dissolution in steel are necessary to provide high Mo yield during steel alloying. The calculated mass balance of 3 ton trial heats showed that only a small part of initial Mo amount (8–13 ppm) has gone into slag.
Processing and Characterization of Dual Phase Steel Foams Featured by Different Pore Distribution
Authors: Castrodeza Enrique M. , Gruttadauria Andrea , Mapelli Carlo , Mombelli Davide
Published: April 2011

Porous materials featuring cellular structures are known to have many interesting combinations of physical and mechanical properties. Some of them have been extensively used in structural applications (i.e. balsa wood), as well as in functional applications (heat exchangers, filters, etc.). Steel foams present promising theoretical properties for both functional and structural applications, but processing such kind of foams is complex due to their high melting temperature. Starting from a technique based on molten metal infiltration into a ceramic space holder, a new process is presented here for open‐cell steel sponges processing. Using a SiC cellular preforms as a space holder, dual phase steels foams with different porosity and steel microstructure were successfully developed.

This technique is suitable to obtain steel alloy sponges featured by a relative density equal to 0,6 and interconnected pores. The compression tests indicate that the resulting material features the typical stress‐strain behaviour of classical cellular metals. Moreover mechanical properties, such as Elastic Modulus, σplateau, εdensification and Eabsorbed, depended on porosity and on martensite fraction, which is a function of the applied intercritical temperature.
Extending the investment development path model to include the human environment factor
Authors: Jiuhua Zhu Cherrie , Thomson S. Bruce , Hutchings Kate , Cieri Helen De
Published: April 2011

This article aims to address Dunning's call to include the “human environment” (HE) as a new trend and trajectory for research in international business (IB). Dunning argues that the most important driver for economic advancement is knowledge, which arises from the HE. We extend Dunning's IB theory of the five stages of a country's investment development path (IDP) to include the HE factor. Further, we use China as an example in which to examine the role of human resource management (HRM). We identify and analyze an important link between foreign direct investment, multinational enterprises, and both domestic and global HRM. © 2011 Wiley Periodicals, Inc.
Understanding the rise of global protectionism
Authors: Enderwick Peter
Published: April 2011

The past three decades are generally regarded as a period of widespread liberalization and high growth within the world economy. On a wide range of measures, this era has seen the rapid globalization of business and the lifting from poverty of a large number of the world's poorest, particularly within large emerging markets such as China and India. While the undoubted benefits of globalization are widely recognized for raising economic growth rates and engaging a much larger number of nations in international business activity, globalization has always had its critics. The purpose of this article is to explore the recent rise in protectionism—what has been termed “global protectionism”— to examine how it differs from traditional forms of trade protectionism, and to offer some tentative assessment of its determinants. ©2011 Wiley Periodicals, Inc.
Chinese host country nationals' willingness to help expatriates: The role of social categorization
Authors: Varma Arup , Budhwar Pawan , Pichler Shaun
Published: April 2011

In this study, we examine Chinese host country nationals' (HCNs') willingness to offer role information and social support to expatriates from the United States. Using data from 132 Chinese managers, we find that ethnocentrism, interpersonal affect, and guanxi significantly impact HCNs' willingness to offer help to expatriates. Furthermore, we find that the job level of the expatriate has a significant impact on HCNs' willingness to offer role information but not on willingness to offer social support. The results suggest that paying attention to the perceptions and reactions of HCNs toward expatriates is imperative for multinational companies if expatriates are to succeed on their assignments. ©2011 Wiley Periodicals, Inc.
Why solidarity matters (and sociability doesn't): The effects of perceived organizational culture on expatriation adjustment
Authors: Pinto Luisa Helena , Cabral‐Cardoso Carlos , Werther William B.
Published: April 2011

This study examines the relationship between perceived organizational culture and cross‐cultural adjustment. Using the organizational culture framework of Goffee and Jones (1996, 1998) that describes organizational culture as the intersection of sociability (e.g., the level of friendliness and socialization between organization members) and solidarity (e.g., the commonality of interests and goals among organization members), this research examines home and host organizational culture as they affect expatriation adjustment regardless of culture novelty (e.g., national cultural differences). The data were obtained through a self‐administered questionnaire filled in by 166 expatriates from 29 nationalities and assigned to 39 countries. The analyses showed that perceived home and host solidarity predicts expatriates' work and general adjustment, though not interactional adjustment. These results confirm that perceived organizational culture is a predictor of expatriation cross‐cultural adjustment. ©2011 Wiley Periodicals, Inc.
Impact of a local host on the success of an international assignment
Authors: van Bakel Marian , Gerritsen Marinel , van Oudenhoven Jan Pieter
Published: April 2011

This longitudinal study examined whether contact with a local host in the Netherlands positively impacts on the adjustment and performance of “Western” expatriates with English or French as their first language. Thirty‐one expatriates were put in contact with a Dutch host with whom they would have regular contact over nine months; another 30 similar expatriates would have no contact with a host. After a five‐month period of contact with a host, there was a positive impact on interaction adjustment. The results also indicated that expatriates who valued the contact highly derived more benefit from it. Contact with a host seems to be especially worthwhile for expatriates who have to deal with host nationals on a daily basis. ©2011 Wiley Periodicals, Inc.
Businesswoman networking: An Eastern perspective
Authors: Alserhan Baker Ahmad , Al‐Waqfi Mohammed A.
Published: April 2011

Networking studies remain limited, often overlooking key structure, content, and cultural issues. This article attempts to fill the gap through describing the networking attributes of composition (who), motives (why), faste and methods (how), and network building and maintenance. Results show that (1) businesswomen indicated a preference for male networks, (2) formal networks were more socially accepted, and (3) online networks are becoming popular. Finally, although businesswomen need to extend their networking activities through participating in mainstream networks, cultural limitations on intergender interactions need to be considered; imposing a specific networking model (i.e., male‐dominated) might force women into more isolation. ©2011 Wiley Periodicals, Inc.
Optimal turbine spacing in fully developed wind farm boundary layers
Authors: Meyers Johan , Meneveau Charles
Published: April 2011

As wind farms become larger, the asymptotic limit of the ‘fully developed’, or ‘infinite’, wind farm has been receiving an increased interest. This limit is relevant for wind farms on flat terrain whose length exceeds the height of the atmospheric boundary layer by over an order of magnitude. Recent computational studies based on large eddy simulation have identified various mean velocity equilibrium layers and have led to parameterizations of the effective roughness height that allow the prediction of the wind velocity at hub height as a function of parameters such as wind turbine spacing and loading factors. In the current paper, we employ this as a tool in making predictions of optimal wind turbine spacing as a function of these parameters, as well as in terms of the ratio of turbine costs to land surface costs. For realistic cost ratios, we find that the optimal average turbine spacing may be considerably higher than that conventionally used in current wind farm implementations. Copyright © 2011 John Wiley & Sons, Ltd.
A developmental perspective on the Virginia Student Threat Assessment Guidelines
Authors: Cornell Dewey G.
Published: April 2011

The Virginia Student Threat Assessment Guidelines were developed to help multidisciplinary school‐based teams use a decision tree to evaluate student threats and take appropriate preventive action. A main goal of this approach is to allow school‐based teams to recognize and respond to the developmental complexities of children and adolescents without resorting to the use of zero tolerance discipline. The model takes a triage approach that involves progressively more extensive assessment and intervention according to the severity of the threat and the student's intentions. The article summarizes two field test studies of the model, a study of training effects on staff attitudes and knowledge about violence prevention, and a quasi‐experimental study showing that secondary schools using the model enjoyed a more positive school climate characterized by less bullying and greater willingness among students to seek help for threats of violence.
Prevention of homicidal violence in schools in Germany: The Berlin Leaking Project and the Networks Against School Shootings Project (NETWASS)
Authors: Leuschner Vincenz , Bondü Rebecca , Schroer‐Hippel Miriam , Panno Jennifer , Neumetzler Katharina , Fisch Sarah , Scholl Johanna , Scheithauer Herbert
Published: April 2011

Since 1999, Germany has experienced at least twelve serious cases of targeted school violence. This article describes two projects designed to fill the gap between universal prevention and emergency response in preventing severe forms of school violence in Germany. The Berlin Leaking Project examined the viability of preventive efforts based on early identification of leaking behavior that often precedes targeted school attacks. Leaking refers to any behavior or communication that indicates a student is preparing to carry out a violent attack. This would include explicit or implied threats of violence, apparent fascination with prior acts of violence such as Columbine, and any evidence of planning or preparation to carry out an attack. The NETWASS project will test a training program and intervention strategy based on those findings, examining the usefulness of a threat assessment approach to prevent violence by training teachers to recognize leaking behavior by students. This approach is extended by training teachers on a larger scale to identify leaking and then having a school‐based team evaluate the student and initiate appropriate interventions, such as mental health services, and in some cases, law enforcement action.