bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermomechanical behaviors and dielectric properties of polyaniline‐doped para‐toluene sulfonic acid/epoxy resin composites
Authors: Belaabed Belkacem , Wojkiewicz Jean Luc , Lamouri Saad , El Kamchi Noureddine , Redon Nathalie
Published: July 2011

Composites based on conductive organic/inorganic fillers dispersed in insulating matrix have been widely investigated because of their widespread applications such as electromagnetic shielding, electrostatic discharge, and sensors. In this context, novel composite materials based on epoxy resin matrix charged with polyaniline (PANI)‐doped para‐toluene sulfonic acid were elaborated. Fourier transform infrared spectroscopy, X‐ray diffraction and scanning electron microscopy were used to check the structure and the morphology of the samples. Viscoelastic behavior and thermal stability of the composites were explored by dynamic mechanical thermal analysis and thermogravimetric analysis. It was shown that the PANI particles exhibited a partial crystalline structure and were homogeneously dispersed in epoxy matrix. Consequently, this structure affected the thermal stability and viscoelastic properties of the composites. Furthermore, the dielectric and electrical properties were investigated up to 1 MHz. Measurements of dielectric properties revealed that with loading fillers in matrix, the dielectric parameters increased to high values at low frequency then decreased at values around 40 and 32 of real and imaginary parts, respectively, at 1 MHz with 15% of PANI content. Copyright © 2011 John Wiley & Sons, Ltd.
Ovarian clear cell carcinoma—bad endometriosis or bad endometrium?
Authors: Gounaris Ioannis , Charnock‐Jones D Stephen , Brenton James D
Published: July 2011

It has become increasingly clear that the four main histological subtypes of epithelial ovarian cancer (EOC), high‐grade serous, endometrioid, clear cell and mucinous, are entities with different epidemiologies, clinical presentations, responses to treatment, and ultimate outcomes. In fact, for all intents and purposes, they can be considered different diseases, their only common denominator being that they frequently involve the ovary and pelvic organs. However, clinical practice has not caught up with these insights and the treatment of EOC is that of a single disease entity. In part, this is because we lack detailed knowledge of the molecular mechanisms driving the pathogenesis of each disease, which is vital in order to develop therapeutic approaches against common driver events. In the last few years, mutations in ARID1A and PIK3CA have been described in a substantial fraction of cases of ovarian clear cell carcinoma, yet the paper by Yamamoto et al in this issue of The Journal of Pathology reveals that PIK3CA mutations can be detected in precursor endometriosis tissues. These and other recent observations underscore the importance of investigating whether mutations in the eutopic endometrium actually predispose to endometriosis and eventually to malignancy. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Hypertriglyceridaemia in statin‐treated type 2 diabetic patients
Authors: Hamilton SJ , Chew GT , Davis TME , Stuckey BGA , Watts GF
Published: July 2011

In this cross‐sectional study, we investigated the prevalence of hypertriglyceridaemia (hyperTG) in 182 statin‐treated type 2 diabetic (T2DM) patients.

Predictors of hyperTG (≥2.3mmol/L) were investigated using logistic regression. The prevalence of hyperTG was 20.9%, with lower prevalence in patients with low‐density lipoprotein (LDL)‐cholesterol <2.5mmol/L (13.7%), and LDL‐cholesterol <2.0mmol/L (8.8%). The prevalence of hyperTG plus low high‐density lipoprotein (HDL)‐cholesterol (≤0.9mmol/L) was lower at 6.0%. The independent predictors of hyperTG were waist circumference (odds ratio [OR] 1.033 [95% confidence interval 1.004–1.063], p=0.027) and glucose (OR 1.30 [1.05–1.61], p=0.01), with glucose being the sole predictor in patients with LDL‐cholesterol <2.5mmol/L (OR 1.45 [1.11–1.89], p=0.01) and LDL‐cholesterol <2.0mmol/L (OR 1.59 [1.12–2.26], p=0.01).

In this group of statin‐treated T2DM patients, the prevalence of hyperTG was relatively high, but lower in patients with lower LDL‐cholesterol levels. Residual hyperTG in statin‐treated patients could be addressed by therapeutic lifestyle interventions aimed at weight loss and improved glycaemic control and by further lowering of LDL‐cholesterol. Copyright © 2011 John Wiley & Sons.
Consumers find food labels confusing and too small to read
Authors: Deakin TA
Published: July 2011

The aim of this research was to determine whether consumers are able to read and understand food labels.

A structured interview was conducted during September 2009 with 176 consumers from a cross section of the population. Consumers, from teenagers to pensioners, were interviewed in a variety of locations including a town centre, a cafe, a supermarket, a commercial workplace, a leisure centre and a fast food restaurant.

The majority of respondents (n=155, 88%) try to lead a healthy lifestyle with 149 (85%) reporting that eating healthily is important to them. Over half of respondents (n=102, 58%) read food labels when purchasing food and drink. When presented with a sample of food labels, more than half of consumers (n=96, 55%) interviewed stated that they did not understand the nutritional information and 108 (61%) reported that the labelling information is too small to read. Three out of four consumers (n=134, 76%) announced that they would value educational material with an integral magnifying glass to help them read and understand food labels. There were no significant differences in the findings attributable to the location of interview.

It was concluded that the majority of consumers try to lead a healthy lifestyle and eat a healthy diet but find food labels confusing and too small to read. Educational material with an integral magnifying glass may assist consumers in making healthier food choices. Copyright © 2011 John Wiley & Sons.
Triple‐B (basal‐bolus‐booster) subcutaneous insulin regimen: a pragmatic approach to managing hospital inpatient hyperglycaemia
Authors: Perera NJ , Harding AJ , Constantino MI , Molyneaux L , McGill M , Chua EL , Twigg SM , Ross GP , Yue DK
Published: July 2011

The objective of this study was to introduce a practical insulin protocol for hospital inpatients with hyperglycaemia.

The acronym BBB emphasised the insulin supply in three components, basal, bolus (nutrition correction) and booster (blood glucose level [BGL] correction). The insulin dosage was based on patient weight and adjusted to BGL at pre‐specified times. Compliance of BGL measurements and insulin injections, and efficacy were evaluated prospectively. Fifty‐seven hospital inpatients with significant hyperglycaemia were treated and compared with 45 historical controls (with similar age, HbA1c and diabetes duration) treated with sliding scale insulin (SSI).

The BGL (mean±SD) was significantly lower during BBB treatment (11.7±2.6 vs 13.6±2.4mmol/L; p<0.0001), while episodes of hyperglycaemia were less (median: 3 [IQR 1–8] vs 7 [IQR 4–12]; p=0.001). Patients who experienced hypoglycaemia were also less likely to have a repeat episode with the BBB protocol (median: 1 [IQR 1–3] vs 3 [IQR 2–4.5]).

The BBB protocol is easy to implement and resulted in significant improvement in BGL control compared with SSI. Copyright © 2011 John Wiley & Sons.
Proteins linked to extinction in contextual fear conditioning in the C57BL/6J mouse
Authors: Li Lin , Boddul Sanjay V. , Patil Sudarshan S. , Zheng Jun‐Fang , An Gunyong , Höger Harald , Lubec Gert
Published: July 2011

Studying fear extinction is a major topic in neuroscience. No information on systematic studies on the linkage of contextual fear conditioning (cFC) with hippocampal protein levels is available and we were therefore interested in protein differences between animals with poor and good extinction. cFC was carried out in C57BL/6J mice, hippocampi were taken and proteins were run on two‐dimensional gel electrophoresis with subsequent quantification of protein spots. In‐gel digestion with trypsin and identification by ion trap MS/MS (high‐capacity ion trap) was used for the identification of significantly different hippocampal proteins between mice with good and poor performance of extinction. Signaling protein ras‐related protein rab‐7A and septin 8 levels were significantly higher in hippocampus of poor extinguishers, whereas ubiquitin carboxyterminal hydrolase isozyme L1 showed higher levels in animals with good extinction performance. A series of additional proteins showed significantly different levels between groups but the abovementioned were confirmed by immunoblotting. The abovementioned proteins have never been reported to be linked to extinction, memory, or learning and herein evidence for the involvement of several proteins in extinction mechanism as well as probably representing pharmaceutical targets is provided. Moreover, it is intriguing to demonstrate the differences between good and poor extinction performance at the protein level.
An enhanced chemically defined SILAC culture system for quantitative proteomics study of human embryonic stem cells
Authors: Wang Shuai , Tian Ruijun , Li Li , Figeys Daniel , Wang Lisheng
Published: July 2011

Stable isotope labeling by SILAC‐based quantitative proteomics analysis provides an unprecedented tool for the study of mechanisms underlying the self‐renewal and differentiation of human embryonic stem cells (hESCs). While we recently reported a chemically defined SILAC culture system specific for a rare cell proteomic reactor (R. Tian et al., Mol. Cell. Proteomics 2011, 10, M110.000679), total hESC yield, prolonged self‐renewal capacity (i.e.<12 days), and laborious procedure remain substantial hurdles for its conventional application in hESC studies. Here, we devised an enhanced SILAC culture system consisting of a new chemically defined SILAC‐medium and a novel culture protocol. As a result, with much less culture maneuvers, approximately 40‐fold greater hESCs were produced than the system reported previously. Moreover, the enhanced SILAC culture system was sufficient to support the self‐renewal of hESCs for >60 days and was also highly reproducible. As such, it provides a new platform that can be readily adapted by general laboratory for further comprehensive SILAC‐based proteomics analysis of hESCs and induced pluripotent stem cells.
Temporal proteomic profiling of embryonic stem cell secretome during cardiac and neural differentiation
Authors: Farina Annarita , D'Aniello Cristina , Severino Valeria , Hochstrasser Denis F. , Parente Augusto , Minchiotti Gabriella , Chambery Angela
Published: July 2011

During recent years, increased efforts have focused on elucidating the pluripotency and self‐renewal of stem cells. Differentiation towards the different lineages has attracted significant attention given the potential use of stem cells in regenerative medicine. Embryonic stem cell differentiation is a complex process coordinated by strictly regulated extracellular signals that act in an autocrine and/or paracrine manner. Through secreted molecules, stem cells affect local niche biology and influence the cross‐talking with the surrounding tissues. Emerging evidence supports the hypothesis that fundamental cell functions, including proliferation and differentiation, are strictly regulated by the complex set of molecules secreted from cells. The understanding of this molecular language could largely increase our knowledge on pathways regulating stem cell differentiation. Here, we have used a proteomics platform to investigate the profile of proteins secreted during differentiation of murine embryonic stem cells. We have followed the dynamics of protein secretion by comparing the secretomes at different time points of murine embryonic stem cell cardiac and neural differentiation. In addition to previously reported molecules, we have identified many secreted proteins not described so far as released from embryonic stem cells nor shown to be differentially released during the process of cardiomyogenesis and neurogenesis.
Optoelectronic property tailoring of conjugated heterocyclic azomethines – the effect of pyrrole, thiophene and furans
Authors: Dufresne Stéphane , Skene W. G.
Published: July 2011

A series of de novo symmetric heterocyclic azomethine dyads and triads consisting uniquely of furans, thiophenes, pyrroles and methyl‐pyrroles were prepared. These were prepared to investigate the effect of various heterocycles and the degree of conjugation on the spectroscopic and electrochemical properties. The crystallographic structures of the symmetric azomethines were also compared with their unsymmetric and heterocyclic and homoaryl counterparts. It was found that for a similar series, bathochromic absorbance and fluorescence shifts occurred when progressing in the order of furan < thiophene < pyrrole ≈ methyl‐pyrrole. The spectroscopic properties of the heterocyclic azomethines were also bathochromically shifted relative to their homoaryl analogues as a result of increased degree of conjugation and electronic effects. The former was in part confirmed by crystallographic studies showing the heterocycles adopted co‐planar and antiparallel arrangements. Although all the compounds studied showed weak fluorescence at room temperature, their fluorescence could be restored at low temperatures, implying deactivation of the singlet excited manifold by bond rotation. Meanwhile, irreversible oxidation was observed for all the azomethines studied and their oxidation potentials were contingent on the heterocycle and number of azomethines, ranging between 0.8 and 1.4 V versus Ag+. The irreversible oxidation was due to radical cation cross‐coupling resulting in products with higher degrees of conjugation. Copyright © 2011 John Wiley & Sons, Ltd.
Theoretical study of the smiles rearrangement in the activation mechanism of proton pump inhibitors
Authors: Reyes‐González Jorge , Gómez Rosa María , Cortés‐Guzmán Fernando
Published: July 2011

This work describes the conformational behavior and the activation mechanism of timoprazole and substituted prazoles from the most stable conformation to the sulphenic acid. The stability of the conformers can be explained by the presence of hydrogen bonds, stereoelectronic effect because of the lone pair of sulfur atom and the N…C and N…S interactions. The first step of the Smile rearrangement is a nucleophilic addition to benzimidazole by pyridine moiety, which depends on the difference of the electron population of the atoms involved in the attack. The second step produces sulphenic acid by a concerted reaction where breaking of the S–C bond goes along with a proton migration, and is determined by the electron population of the sulfur atom. Copyright © 2011 John Wiley & Sons, Ltd.
The Development of Frost‐weathering Microstructures on Sand‐sized Quartz Grains: Examples from Poland and Mongolia
Authors: Woronko Barbara , Hoch Małgorzata
Published: July 2011

Quartz grains, 0.25−1.0 mm in diameter, taken from Pleistocene sands and a palaeo‐active layer in Poland (Łódź Teofilów) and from silty‐clayey sediments of the contemporary active layer near Ulaanbaatar (Mongolia) were analysed using a scanning electron microscope (SEM). Other analyses included granulometric composition, and frosting and rounding of quartz grains. The effects of frost weathering comprise several microstructures, such as breakage blocks (>10 µm and <10 µm), surface coating and scaling, among which breakage blocks <10 µm are apparently the most common. Two types of frost weathering were distinguished. Weathering of the P type is mainly initiated on convex fragments of grains as the result of ice segregation. Weathering of the F type is linked to the volumetric expansion of ice and usually observed within concave linear microstructures. A frost action index (FAI) was developed based on the frequency of occurrence of microstructures from frost weathering. The FAI value varies between 0 and 3, and the higher the value, the more intensive the frost weathering. The value of the FAI in sediments from the Polish study site is relatively low with a maximum barely exceeding 1. The FAI values from the Ulaanbaatar site are higher in all of the sediment samples with a maximum of 2. Copyright © 2011 John Wiley & Sons, Ltd.
Statistical Analyses of Active Patterned Ground Occurrence in the Taillon Massif (Pyrénées, France/Spain)
Authors: Feuillet Thierry
Published: July 2011

Statistical approaches were used to describe and explain the presence or absence of active patterned ground features in a mid‐latitude alpine area. The relative rarity of these landforms can be problematic for such analyses but this issue was resolved by a novel spatial sampling strategy that considers only terrain within circles drawn around each observed patterned ground feature, which is then subdivided into a grid. This strategy focuses only on fields with potential patterned ground occurrence and can be used for all statistical studies concerning the occurrence of scattered features over extensive areas. These data were examined using factor analyses (multiple correspondence analysis and hierarchical ascendant classification) blended with a complementary bivariate method to associate patterned ground occurrence with eight environmental variables (elevation, exposure, height‐distance ratio, drift, glacier influence, vegetation cover, slopewash and lithology). The absence of active patterned ground is associated with low elevation, glacier absence, no slopewash, a low height‐distance ratio and talus fans. Zones where active patterned ground features are present are divided into three homogeneous subzones and are mostly associated with glacier influence, a large height‐distance ratio and an absence of vegetation. Their location is controlled by the presence of till from different glacial sequences so that the former and current presence of glaciers favours the development of patterned ground features at the landscape scale. Copyright © 2011 John Wiley & Sons, Ltd.
Crystal structure of New Delhi metallo‐β‐lactamase reveals molecular basis for antibiotic resistance
Authors: King Dustin , Strynadka Natalie
Published: July 2011

β‐Lactams are the most commonly prescribed class of antibiotics and have had an enormous impact on human health. Thus, it is disquieting that an enzyme called New Delhi metallo‐β‐lactamase‐1 (NDM‐1) can confer Enterobacteriaceae with nearly complete resistance to all β‐lactam antibiotics including the carbapenams. We have determined the crystal structure of Klebsiella pneumoniae apo‐NDM‐1 to 2.1‐Å resolution. From the structure, we see that NDM‐1 has an expansive active site with a unique electrostatic profile, which we propose leads to a broader substrate specificity. In addition, NDM‐1 undergoes important conformational changes upon substrate binding. These changes have not been previously observed in metallo‐β‐lactamase enzymes and may have a direct influence on substrate recognition and catalysis.
Surface chemistry of the preferred (111) and (220) crystal oriented microcrystalline Si films by radio‐frequency plasma‐enhanced chemical vapor deposition
Authors: Ohba Daisuke , Koshino Hideto , Tang Zeguo , Shirai Hajime
Published: July 2011

The surface chemistry of the preferentially (111) and (220) crystal orientated chlorinated hydrogenated microcrystalline silicon (µc‐Si:H:Cl) films was studied using a rf PE‐CVD of a dichlorosilane (SiH2Cl2) and H2 mixture. The growing surface for the preferentially (220) crystal oriented µc‐Si:H:Cl films included much voids and dangling bonds, whereas the growing surface with the preferential (111) crystal orientation was chemically stable relatively. These findings suggest that the sticking process of deposition precursors and/or the reconstruction of Si clusters within the sub‐surface determine the preferential crystal orientation. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Light management of a‐Si:H solar cells using textured zinc oxide with adjustable haze values
Authors: Zhang Liping , Yunaz Ihsanul Afdi , Kasashima Shunsuke , Wada Hidetoshi , Hongsingthong Aswin , Krajangsang Taweewat , Kurokawa Yasuyoshi , Konagai Makoto
Published: July 2011

Boron doped zinc oxide (ZnO) films to be applied as transparent conductive oxide (TCO) in single junction pin hydrogenated amorphous silicon (a‐Si:H) solar cells were fabricated using metal organic chemical vapour deposition (MOCVD) technique. ZnO films with various haze values and surface root mean square (RMS) roughnesses were obtained by adjusting the thickness of films. B‐doped concentration presented a little effect on the RMS roughness of ZnO films but produced an adjustable sheet resistance. A series of ZnO films with a similar sheet resistance of ∼10 Ω/□ but different RMS roughnesses were applied in a‐Si:H solar cells as TCOs. The intrinsic a‐Si:H thin films with different thicknesses were used as the active layer of solar cells. It was found that the optimum RMS roughness strongly depended on the thickness of active layer. It was also confirmed that higher short‐circuit current density (Jsc) could be achieved by employing TCO with higher RMS roughness due to effective light trapping. A stabilized conversion efficiency of 9.3% and a Jsc of 16.9 mA/cm2 were obtained by utilizing ZnO TCO with a surface RMS roughness of 95 nm for a single junction pin a‐Si:H solar cell without any antireflective coating. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Large area PECVD of a‐Si:H/a‐Si:H tandem solar cells
Authors: Gabriel Onno , Kirner Simon , Leendertz Caspar , Gerhardt Mario , Heidelberg Andreas , Bloeß Harald , Schlatmann Rutger , Rech Bernd
Published: July 2011

We report on recent developments of a‐Si:H/a‐Si:H based thin film solar cells on Gen8.5 module area. The initial efficiency of 5.7 m² modules and 1.4 m² sub‐modules has been increased from 5% to 8% using standard floatline, low‐cost glass substrates coated with SnO2:F front TCO. The improvements based on optimizations of the n1/p2 tunnel recombination junction and of the p/i interfaces. The device simulation software AFORS‐HET has been extended with an improved model for the n/p junction to describe measured module properties. Model input parameters are taken from measured properties of single thin films. The presented progress indicates the high potential of thin‐film silicon based solar cells produced on large area. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thinner silicon‐based tandem solar cell with high efficiency made by hot wire CVD
Authors: Xin Jin , van der Werf K. H. M. , Schropp R. E. I.
Published: July 2011

We developed thin film silicon tandem cells with hot‐wire deposited amorphous (protocrystalline) and nanocrystalline i‐layers, with a total thickness of only 1.43 µm. This is considerably thinner than the thickness of 2.5–3.0 µm normally needed, which is important to significantly reduce production costs for this type of cells. An initial efficiency of 8.84% was obtained. The top cell is ∼220 nm and the bottom cell only ∼1210 nm thick. No intermediate reflector layer is introduced. Compared to standard PECVD tandem cells, the Voc is remarkably high, consistent with the beneficial effect of thin i‐layers on Voc and with the high Voc of 0.57 V obtained for single junction HWCVD nc‐Si:H cells. After over 2000 hours of light soaking, a stabilized efficiency of 7.63% was obtained (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hybrid sensitized solar cells using Si nanoparticles and ruthenium dye
Authors: Uchida Giichiro , Kawashima Yuki , Yamamoto Kosuke , Sato Muneharu , Nakahara Kenta , Matsunaga Takeaki , Yamashita Daisuke , Matsuzaki Hidefumi , Kamataki Kunihiro , Itagaki Naho , Koga Kazunori , Kondo Michio , Shiratani Masaharu
Published: July 2011

We fabricated hybrid sensitized solar cells using ruthenium (Ru) dye and silicon (Si) nanoparticles synthsized by multi‐hollow discharge plasma CVD using SiH4/H2 gas mixture. The power conversion efficiency (η) was measured as a parameter of the Si nanoparticles/TiO2 weight ratio to reveal effects of Si nanoparticles on the device performance. The short circuit current increases with the weight ratio. The η of the hybrid sensitized solar cells is improved up to 3.0% compared to 2.4% of the cell without Si nanoparticles under AM 1.5, 100 mW/cm2 light irradiation. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of Saffron (Crocus sativus L.) and its Active Constituent, Crocin, on Recognition and Spatial Memory after Chronic Cerebral Hypoperfusion in Rats
Authors: Hosseinzadeh Hossein , Sadeghnia Hamid Reza , Ghaeni Fatemeh Abbasi , Motamedshariaty Vahideh Sadat , Mohajeri Seyed Ahmad
Published: July 2011

Cerebral ischemia produces brain damage and related behavioral deficits such as memory. In this study, a rat model of chronic cerebral hypoperfusion was used to determine whether saffron extract and crocin, which are potent antioxidants and free radical scavengers, can reduce vascular cognitive impairment. Male adult Wistar rats were administered different doses of an aqueous solution of crocin or hydroalcohol extract of saffron intraperitoneally (i.p.) 5 days after permanent occlusion of the common carotid arteries. Spatial learning and memory were assessed in training trials, 7–11 days after common carotid artery ligation using the Morris water maze. The results showed that the escape latency time was significantly reduced from 24.64 s in the control group to 8.77 and 10.47 s by crocin (25 mg/kg) and saffron extract (250 mg/kg). The traveled distance to find the platform was also changed from 772 cm in the control group to 251 and 294 cm in the crocin (25 mg/kg) and saffron extract (250 mg/kg) groups. The percentages of time spent in the target quadrant, in comparison with the control group (24.16%), increased to 34.25% in the crocin (25 mg/kg) and 34.85% in the saffron extract (250 mg/kg) group. This study suggests that saffron extract and crocin improve spatial cognitive abilities following chronic cerebral hypoperfusion and that these effects may be related to the antioxidant effects of these compounds. Copyright © 2011 John Wiley & Sons, Ltd.
A Comparative Life Cycle Assessment of Disposable and Reusable Packaging for the Distribution of Italian Fruit and Vegetables
Authors: Levi Marinella , Cortesi Sara , Vezzoli Carlo , Salvia Giuseppe
Published: July 2011

Each year in Italy, millions of tons of fruits and vegetables are harvested, packed and transported to national and foreign retail outlets. Packaging is an essential component of this system, but what is its environmental impact?

This study takes into consideration the delivery from the field to the retail outlet of 12 types of fruits and vegetables grown and harvested in Italy and sold in Italy and Europe. The study compares two different packaging and distribution systems: one‐way with corrugated boxes and reusable with plastic containers.

A number of different scenarios were generated by combining the most diffused packaging sizes with the most important production and selling locations for each type of fruit and vegetable and by considering the specific route required to perform the transportation with each distribution system.

The environmental impact of each system in each scenario has then been analysed using the life cycle assessment methodology.

Two algorithms and a number of coefficients were derived to simplify data collection and impact analysis for all scenarios. This provides an easy tool to evaluate the potential environmental burden of the two alternative distribution systems in a specific scenario by taking into consideration only a few variables (such as size of packaging and transportation distance).

These algorithms and coefficients are presented in the work, along with the process that led to their generation and with considerations about the main critical environmental aspects for both distribution systems. The work aims to suggest possible design solutions that can make each system more sustainable. Copyright © 2011 John Wiley & Sons, Ltd.
On the Statistical Distribution of Road Vehicle Vibrations
Authors: Garcia‐Romeu‐Martinez Manuel‐Alfredo , Rouillard V.
Published: July 2011

This paper presents an alternative method for characterizing the random vibrations produced by transport vehicles. The paper discusses the significance and limitations of the average power spectral density and explains why it is not always adequate as the sole descriptor of road vehicle vibrations as the process generally tends to be non‐stationary and non‐Gaussian. The paper adopts an alternative analysis method, based on the statistical distribution of the moving root‐mean‐square (rms) vibrations, as a supplementary indicator of overall ride quality. A variety of sample vibration records, collected from various vehicle types and routes in Spain and Australia, were used to investigate the suitability of various mathematical models, based on the Weibull distribution. It shows that the model can also effectively describe the statistical parameters of the process, namely the mean, median, standard deviation, skewness and kurtosis. The paper proposes a single mathematical model that can accurately describe the statistical character of the non‐stationary random vibrations generated by road vehicles in general. The proposed generic distribution model, based on the Weibull distribution, was developed to afford additional control over various aspects of the shape of the distribution function. The model was found to be general enough to be able to produce a range of well‐known distributions. Curve‐fitting results using the sum‐of‐squared error (least squares) optimization were found to produce non‐convergent results, which required inclusion of the mean, median, standard deviation, skewness and kurtosis in the optimization algorithm. The paper also shows how the model is capable of accurately describing the statistical parameters of the process, namely the mean, median, standard deviation, skewness and kurtosis. This result is relevant not only for the characterization of ride quality but also for the accurate synthesis of road vehicle vibrations in the laboratory. The results can be used to assist in developing a novel method for simulating non‐stationary (modulated) vibration in the laboratory. The rms distribution function can be used to create an rms level schedule that will enable the synthesis of random vibrations with varying rms levels to better represent the road transport vibration process. Copyright © 2011 John Wiley & Sons, Ltd.
The mesoscale structure of a polar low: airborne lidar measurements and simulations
Authors: Wagner J. S. , Gohm A. , Dörnbrack A. , Schäfler A.
Published: July 2011

The mesoscale structure of a mature polar low was studied on the basis of high‐resolution airborne measurements and numerical modelling. A polar low was measured by light detection and ranging (lidar) and dropsonde observations over the Norwegian Sea on 3 and 4 March 2008. Lidar observations provided cross‐sections of water‐vapour mixing ratio, backscatter ratio and horizontal wind speed around the polar low and through its centre. Mesoscale structures, such as shallow convection in a cold‐air outbreak, a dry intrusion in the eye‐like centre of the cyclone and deep convection surrounding it could be identified. Numerical simulations were performed with the European Centre for Medium‐Range Weather Forecasts (ECMWF) Integrated Forecast System (IFS) and a high‐resolution, polar version of the Weather Research and Forecasting (WRF) model. WRF simulations reproduced these structures and showed that the polar low had a warm, upper‐level core with descending motions. The eye‐like centre had a diameter of about 100–150 km and was characterized by rather stable stratification, horizontally constant potential temperatures and calm winds. Beyond the centre, wind speeds increased rapidly. The observed radial wind and temperature profiles support previous idealized simulations. Several WRF sensitivity tests showed the influence of the initialization time and sensible and latent heat fluxes from the surface on the simulated polar‐low development. The polar‐low simulations were more accurate in runs starting at the mature stage. Heat fluxes from the surface were important for the polar‐low energetics, especially at the final stages. Copyright © 2011 Royal Meteorological Society
Predicting outliers in ensemble forecasts
Authors: Siegert Stefan , Bröcker Jochen , Kantz Holger
Published: July 2011

An ensemble forecast is a collection of runs of a numerical dynamical model, initialized with perturbed initial conditions. In modern weather prediction for example, ensembles are used to retrieve probabilistic information about future weather conditions. In this contribution, we are concerned with ensemble forecasts of a scalar quantity (say, the temperature at a specific location). We consider the event that the verification is smaller than the smallest, or larger than the largest ensemble member. We call these events outliers. If a K‐member ensemble accurately reflected the variability of the verification, outliers should occur with a base rate of 2/(K + 1). In operational forecast ensembles though, this frequency is often found to be higher. We study the predictability of outliers and find that, exploiting information available from the ensemble, forecast probabilities for outlier events can be calculated which are more skilful than the unconditional base rate. We prove this analytically for statistically consistent forecast ensembles. Further, the analytical results are compared to the predictability of outliers in an operational forecast ensemble by means of model output statistics. We find the analytical and empirical results to agree both qualitatively and quantitatively. Copyright © 2011 Royal Meteorological Society
Adaptive dynamic surface control for pure‐feedback systems
Authors: Zhao Qichao , Lin Yan
Published: July 2011

This paper proposes a novel dynamic surface control algorithm for a class of uncertain nonlinear systems in completely non‐affine pure‐feedback form. Instead of using the mean value theorem, we construct an affine variable at each design step, and then neural network is employed to deduce a virtual control signal or an actual control signal. As a result, the unknown control directions and singularity problem raised by the mean value theorem is circumvented. The proposed scheme is able to overcome the explosion of complexity inherent in backstepping control and guarantee the tracking performance by introducing an initialization technique based on a surface error modification. Simulation results are presented to demonstrate the efficiency of the proposed scheme. Copyright © 2011 John Wiley & Sons, Ltd.
On the robust stability of time‐varying uncertain genetic regulatory networks
Authors: Chesi Graziano , Chen Luonan , Aihara Kazuyuki
Published: July 2011

This paper investigates robust stability of time‐varying uncertain genetic regulatory networks (GRNs). In particular, the considered model includes, as special cases, SUM and PROD regulatory functions typically considered in the literature. It is supposed that the coefficients of the GRN are affine linear functions of an uncertain vector constrained in a polytope, and that the activation functions are uncertain into sector‐type regions. As the first problem, we consider to establish whether the GRN is robustly globally stable for all admissible uncertainties. It is shown that this problem can be addressed by solving a linear matrix inequality (LMI) feasibility test built by exploiting homogeneous polynomial Lyapunov functions. As the second problem, we consider to determine the slowest speed with which the concentrations of mRNAs and proteins reach their equilibrium values. It is shown that a guaranteed underestimate of such a speed can be provided by solving a generalized eigenvalue problem built from the proposed stability condition. Some numerical examples illustrate the proposed approaches. It is worth remarking that this paper proposes for the first time in the literature the use of nonquadratic Lyapunov functions for studying robust stability of uncertain GRNs, whereas existing works have addressed the problem only via quadratic Lyapunov functions (either common or parameter‐dependent), which are known to be conservative for time‐varying uncertainty. Copyright © 2011 John Wiley & Sons, Ltd.
Pósa's conjecture for graphs of order at least 2 × 108
Authors: Châu Phong , DeBiasio Louis , Kierstead H.A.
Published: July 2011

In 1962 Pósa conjectured that every graph G on n vertices with minimum degree
\documentclass{article} \usepackage{mathrsfs} \usepackage{amsmath,amssymb,amsfonts} \pagestyle{empty} \begin{document} \begin{align*}\delta(G)\ge \frac{2}{3}n\end{align*} \end{document}
contains the square of a hamiltonian cycle. In 1996 Fan and Kierstead proved the path version of Pósa's Conjecture. They also proved that it would suffice to show that G contains the square of a cycle of length greater than
\documentclass{article} \usepackage{mathrsfs} \usepackage{amsmath,amssymb,amsfonts} \pagestyle{empty} \begin{document} \begin{align*}\frac{2}{3}n\end{align*} \end{document}. Still in 1996, Komlós, Sárközy, and Szemerédi proved Pósa's Conjecture, using the Regularity and Blow‐up Lemmas, for graphs of order n ≥ n0, where n0 is a very large constant. Here we show without using these lemmas that n0:= 2 × 108 is sufficient. We are motivated by the recent work of Levitt, Sárközy and Szemerédi, but our methods are based on techniques that were available in the 90's. © 2011 Wiley Periodicals, Inc. Random Struct. Alg., 2011
X‐ray microanalysis of porous materials using Monte Carlo simulations
Authors: Poirier Dominique , Gauvin Raynald
Published: July 2011

Quantitative X‐ray microanalysis models, such as ZAF or φ(ρz) methods, are normally based on solid, flat‐polished specimens. This limits their use in various domains where porous materials are studied, such as powder metallurgy, catalysts, foams, etc. Previous experimental studies have shown that an increase in porosity leads to a deficit in X‐ray emission for various materials, such as graphite, Cr2O3, CuO, ZnS (Ichinokawa et al., '69), Al2O3, and Ag (Lakis et al., '92). However, the mechanisms responsible for this decrease are unclear. The porosity by itself does not explain the loss in intensity, other mechanisms have therefore been proposed, such as extra energy loss by the diffusion of electrons by surface plasmons generated at the pores–solid interfaces, surface roughness, extra charging at the pores–solid interface, or carbon diffusion in the pores. However, the exact mechanism is still unclear. In order to better understand the effects of porosity on quantitative microanalysis, a new approach using Monte Carlo simulations was developed by Gauvin (2005) using a constant pore size. In this new study, the X‐ray emissions model was modified to include a random log normal distribution of pores size in the simulated materials. This article presents, after a literature review of the previous works performed about X‐ray microanalysis of porous materials, some of the results obtained with Gauvin's modified model. They are then compared with experimental results. SCANNING 33: 126–134, 2011. © 2011 Wiley Periodicals, Inc.
Mediated Effects of Physical Risk Factors, Leader–Member Exchange and Empowerment in Predicting Perceived Injury Risk
Authors: Muldoon Jeffery , Matthews Russell A. , Foley Caroline
Published: July 2011

In the context of conservation of resources theory, we examine the indirect (mediated) effects of physical risk factors, leader–member exchange (LMX) and empowerment on perceived injury risk in a heterogeneous sample (N = 226) of individuals employed in occupations related to production, construction and installation/maintenance. Positioning work role stressors and upward safety communications as two important mediating variables, as predicted, LMX and empowerment demonstrated significant indirect effects on perceived injury risk. Results from our model also provide preliminary evidence that an asymmetrical dualistic process exists in terms of the effect physical risk factors have on perceived injury risk via depletion of both psychological (i.e. role stressors) and physical resources (i.e. physical symptoms). Theoretical and practical implications based on the results of our model are also discussed. Copyright © 2011 John Wiley & Sons, Ltd.
Repair of Critical-Sized Rat Calvarial Defects Using Genetically Engineered Bone Marrow-Derived Mesenchymal Stem Cells Overexpressing Hypoxia-Inducible Factor-1α
Authors: Zou Duohong , Zhang Zhiyuan , Ye Dongxia , Tang Aifa , Deng Lianfu , Han Wei , Zhao Jun , Wang Shuhong , Zhang Wenjie , Zhu Chao , Zhou Jian , He Jiacai , Wang Yuanyin , Xu Feng , Huang Yuanliang , Jiang Xinquan
Published: July 2011

The processes of angiogenesis and bone formation are coupled both temporally and spatially during bone repair. Bone marrow-derived mesenchymal stem cells (BMSCs) have been effectively used to heal critical-size bone defects. Enhancing their ability to undergo angiogenic and osteogenic differentiation will enhance their potential use in bone regeneration. Hypoxia-inducible factor-1α (HIF-1α) has recently been identified as a major regulator of angiogenic-osteogenic coupling. In this study, we tested the hypothesis that HIF-1α gene therapy could be used to promote the repair of critical-sized bone defects. Using lentivirus-mediated delivery of wild-type (HIF) or constitutively active HIF-1α (cHIF), we found that in cultured BMSCs in vitro, HIF and cHIF significantly enhanced osteogenic and angiogenic mRNA and protein expression when compared with the LacZ group. We found that HIF-1α-overexpressing BMSCs dramatically improved the repair of critical-sized calvarial defects, including increased bone volume, bone mineral density, blood vessel number, and blood vessel area in vivo. These data confirm the essential role of HIF-1α modified BMSCs in angiogenesis and osteogenesis in vitro and in vivo.
Crystal Structure, Solution and Solid‐state Photoluminescence of a 2D Zinc(II) Supramolecular Architecture
Authors: Ren Yi‐Xia , Jiao Bao‐Juan , Zhang Mei‐Li , Gao Xiao‐Ming , Wang Jiao
Published: July 2011

A new 2D zinc(II) supramolecular complex [Zn(2,4‐D)(o‐phen)(H2O)2](NO3) (1) (2,4‐D = 2,4‐dichlorophenoxyacetic acid, o‐phen = 1,10‐phenanthroline), was synthesized and characterized by single‐crystal X‐ray diffraction, elemental analyses, TG analysis, IR, and luminescence spectroscopy. For complex 1, each ZnII ion lies in a pentacoordinate distorted quadrilateral pyramidal configuration. The 8‐member‐ring hydrogen bonds clusters result in 1D ladder‐like supramolecular chains, which further stack up by face‐to‐face π–π stacking interactions into 2D supramolecular layers. The TG analysis shows that complex 1 has high thermal stability. The solution and solid‐state photoluminescence of 1 are reported.
Visitor reaction to pacing behavior: influence on the perception of animal care and interest in supporting zoological institutions
Authors: Miller Lance J.
Published: July 2011

Many publications within the field of zoo animal welfare have stated the importance of decreasing stereotypic behavior (e.g., pacing) to help ensure a positive visitor experience. The idea behind these statements is that visitors want to see animals engaged in natural behavior. Additionally, it is thought that watching an animal exhibit species‐appropriate behavior could help increase a visitor's connection to wildlife and ultimately their interest in conservation. However, until recently, no information was available to validate such statements. The purpose of this research was to examine people's reaction to viewing an animal engaged in pacing behavior. Participants were randomly selected to fill out a survey after watching a short video of either a tiger pacing or resting (control). Results indicate that having viewed a tiger pacing significantly decreases people's perception of the level of care animals receive at that facility. In addition, people's interest in supporting zoos decreased as a result of viewing this behavior. Results are discussed from an animal welfare, business, and conservation perspective. Zoo Biol 31: 242–248, 2012. © 2011 Wiley Periodicals, Inc.
Correlation of Vascular Endothelial Growth Factor Expression With Tumor Recurrence and Poor Prognosis in Patients With pN0 Gastric Cancer
Authors: Liu Yan‐feng , Guo Sen , Zhao Rui , Chen Yue‐guang , Wang Xian‐qiang , Xu Ke‐sen
Published: July 2011

Background

Vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)‐9 play important roles in tumor angiogenesis, development, and progression. This study investigates the expression of VEGF combined with MMP‐9, their correlation with clinical characteristics, and their effect on the prognosis for patients with pN0 gastric cancer after curative surgery.

Methods

A total of 55 patients were enrolled in the study. They were analyzed by immunohistochemistry, and their correlation with clinical characteristics was then investigated. Their relations and the survival time of patients were retrospectively analyzed.

Results

VEGF and MMP‐9 were positively expressed in 24 (43.6%) and 16 (29.1%) patients, respectively, and had a positive correlation (r = 0.324, p = 0.016) in the Spearman rank correlation analysis. Univariate analysis showed that VEGF, MMP‐9 expression, vascular invasion, T stage, and tumor size were associated with tumor recurrence as well as the disease‐specific (DSS) and overall (OS) survival rates. Patients with positive VEGF expression showed significantly higher recurrence and poorer DSS and OS rates compared with those with negative VEGF expression. Multivariate analysis showed that VEGF expression, vascular invasion, T stage (serosal invasion), and tumor size were significant independent prognostic factors for tumor recurrence, DSS, and OS in patients with pN0 gastric cancer with the exception that T stage was not for DSS.

Conclusions

VEGF expression, vascular invasion, T stage (serosal invasion), and tumor size can be used as valuable prognosticators in predicting tumor recurrence and prognosis for patients with pN0 gastric cancer after curative surgery. VEGF may have a synergistic effect with MMP‐9 during tumor angiogenesis, development, and progression.
External Validation of Two Nomograms for Predicting Patient Survival After Hepatic Resection for Metastatic Colorectal Cancer
Authors: Takakura Yuji , Okajima Masazumi , Kanemitsu Yukihide , Kuroda Shintaro , Egi Hiroyuki , Hinoi Takao , Tashiro Hirotaka , Ohdan Hideki
Published: July 2011

Background

Two nomograms are available for predicting patient survival after hepatic resection for metastatic colorectal cancer (CRC). However, they have not been externally validated using other databases, and so their universal applicability has not been established. We aimed to examine the validity of these nomograms for predicting patient survival after hepatic resection for metastatic CRC in different institutions.

Methods

We analyzed the cases of 113 patients who underwent hepatic resection for metastatic CRC at Hiroshima University Hospital between 1995 and 2006. In this patient set, we assessed the predictive value of the Kattan nomogram of the Memorial Sloan‐Kettering Cancer Center (MSKCC) (United States) and the Kanemitsu nomogram from the Aichi Cancer Center (Japan). The concordance index was used as an accuracy measure for comparing these two nomograms. The predictive accuracy of these nomograms was compared with that of conventional predictive models.

Results

The 3‐, 5‐, and 10‐year overall survival rates in our cohort were 66.3%, 52.4%, and 42.7%, respectively. The concordance indexes of the pre‐ and postoperative Kanemitsu nomogram and that of the Kattan nomogram were 0.70, 0.69, and 0.68, respectively. These values were higher than those obtained using other models for hepatic metastatic CRC, including the clinical risk score of the MSKCC and the grading system of the Japanese Society for Cancer of the Colon and Rectum.

Conclusions

The high predictive accuracy of both nomograms shows that these predictive tools can be used in different institutions. Patient counseling and adjuvant therapy decision‐making should benefit from use of these nomograms.