bluuebunny/crossref_metadata_2025 huggingface dataset:
A flexible nonlinear modelling framework for nonstationary generalized extreme value analysis in hydroclimatology
Authors: Cannon Alex J.
Published: November 2009

Parameters in a generalized extreme value (GEV) distribution are specified as a function of covariates using a conditional density network (CDN), which is a probabilistic extension of the multilayer perceptron neural network. If the covariate is time or is dependent on time, then the GEV‐CDN model can be used to perform nonlinear, nonstationary GEV analysis of hydrological or climatological time series. Owing to the flexibility of the neural network architecture, the model is capable of representing a wide range of nonstationary relationships. Model parameters are estimated by generalized maximum likelihood, an approach that is tailored to the estimation of GEV parameters from geophysical time series. Model complexity is identified using the Bayesian information criterion and the Akaike information criterion with small sample size correction. Monte Carlo simulations are used to validate GEV‐CDN performance on four simple synthetic problems. The model is then demonstrated on precipitation data from southern California, a series that exhibits nonstationarity due to interannual/interdecadal climatic variability. Copyright © 2009 Her Majesty the Queen in right of Canada. Published by John Wiley & Sons, Ltd.
Role of thermodynamic and kinetic parameters in gadolinium chelate stability
Authors: Idée Jean‐Marc , Port Marc , Robic Caroline , Medina Christelle , Sabatou Monique , Corot Claire
Published: November 2009

In recent years there has been a renewed interest in the physicochemical properties of gadolinium chelates (GC). The aim of this review is to discuss the physicochemical properties of marketed GC with regard to possible biological consequences. GC can be classified according to three key molecular features: 1) the nature of the chelating moiety: either macrocyclic molecules in which Gd3+ is caged in the preorganized cavity of the ligand, or linear, open‐chain molecules; 2) ionicity: the ionicity of the molecule varies from neutral to tri‐anionic agents; and 3) the presence or absence of an aromatic lipophilic moiety, which has a profound impact on the biodistribution of the GC. These parameters can also explain why GC differ considerably with regard to their thermodynamic stability constants and kinetic stability, as demonstrated by numerous studies. The concept of thermodynamic and kinetic stability is critically discussed, as it remains somewhat controversial, especially in predicting the amount of free gadolinium that may result from decomplexation of chelates in physiologic or pathologic situations. This review examines the possibility that the high kinetic stability provided by the macrocyclic structure combined with a high thermodynamic stability (reinforced by ionicity for macrocyclic chelates) can minimize the amount of free Gd3+ released in the body. J. Magn. Reson. Imaging 2009;30:1249–1258. © 2009 Wiley‐Liss, Inc.
Genome shuffling of Zygosaccharomyces rouxii to accelerate and enhance the flavour formation of soy sauce
Authors: Cao Xiaohong , Hou Lihua , Lu Meifang , Wang Chunling , Zeng Bin
Published: November 2009

BACKGROUND: The purpose of this study was to achieve rapid improvement of the flavour of soy sauce by increasing the salt stress resistance of Zygosaccharomyces rouxii. Here, we describe genome shuffling to improve the salt tolerance of Z. rouxii while simultaneously enhancing and accelerating flavour formation of soy sauce.

RESULTS: A mutant, S3‐2, with a stronger resistance to salt, was selected after three rounds of genome shuffling. S3‐2 not only grew well in peptone/yeast extract/dextrose medium containing a high salt content with wide range of pH, but also exhibited stronger stress resistance to potassium chloride and lithium chloride. In high‐salt liquid fermentation, S3‐2 obviously accelerated flavour formation of soy sauce, thus decreasing the total time required for development of the aroma. In addition, S3‐2 gave high amino acid nitrogen and good flavour. In particular, the ethyl acetate content was 2.38 times that in the control. S3‐2 distinctly improved the formation of 4‐hydroxy‐2 (or 5) ‐ethyl‐5 (or 2) ‐methyl‐3 (2H) ‐furanone by up to 75%. Another important flavour component, 4‐ethylguaiacol, was also detected.

CONCLUSIONS: Genome shuffling was successfully used to achieve significant improvements in flavour formation. The selected strain improved the main flavour components and amino acid nitrogen, thereby enhancing the quality of soy sauce. Copyright © 2009 Society of Chemical Industry
Modified Harrington reconstruction for advanced periacetabular metastatic disease
Authors: Ho Lance , Ahlmann Elke R. , Menendez Lawrence R.
Published: November 2009

Background/Objectives

Destructive metastatic lesions about the acetabulum result in pain and functional limitations. We assessed whether periacetabular reconstruction (PAR) improves quality of life by examining outcome measures of pain, function, and mobility.

Methods

Thirty‐seven patients with a mean follow‐up of 23.6 months (range, 0.5–112 months) were retrospectively reviewed. All patients underwent modified Harrington reconstruction with periacetabular screws, cement, and total hip arthroplasty.

Results

The mean preoperative MSTS score of 14 (47%, 14/30) improved to 20 (67%, 20/30) after the procedure. Thirty‐five patients who were alive 1 month after the procedure were reviewed for outcome. Postoperatively, patients reported a significant improvement in pain (P < 0.0001), mobility (P < 0.0385), and function (P < 0.0186). Kaplan–Meier survivorship curves showed 59% implant‐ and 55% patient survival at 2 years; and 49% implant‐ and 39% patient survival at 5 years. Complications included infection (16%, 6/37) and instability (16%, 6/37).

Conclusions

Our experience with PAR has shown good results with improved postoperative functional scores. Implants will generally exceed life expectancy and are an option to restore quality of life. J. Surg. Oncol. 2010;101:170–174. © 2009 Wiley‐Liss, Inc.
A high‐throughput method for determining chloramphenicol residues in poultry, egg, shrimp, fish, swine and bovine using LC‐ESI‐MS/MS
Authors: Rocha Siqueira Silvia Regina , Luiz Donato José , de Nucci Gilberto , Reyes Felix Guillermo Reyes
Published: November 2009

A LC‐ESI‐MS/MS method for determining chloramphenicol residues in fish, shrimp, poultry, eggs, bovine and swine was developed and validated. The samples were extracted with a phosphate extraction solution followed by liquid–liquid extraction with ethyl acetate. The LC was performed on a C18 column at room temperature. For all the matrices, the analytical curves showedrvalues and recoveries higher than 0.99 and 50%, respectively. The accuracy values lay between 85 and 120% and the precision was lower than 20%. The LOQ was 0.1 ng/g. The method was employed to analyze samples collected in Brazil.
Reversed phase capillary HPLC using polymer‐entrapped C18 particles
Authors: Gibson Graham T. T. , Marecak Dale M. , Oleschuk Richard D.
Published: November 2009

Novel capillary columns containing polymer‐entrapped octadecylsilyl‐modified silica microspheres were evaluated for chromatographic performance. The polymer forms only at the particle surface and in as little as 10 s strongly immobilizes them, obviating the need for a frit. The photoinitiated polymerization is patternable, and various entrapment styles were compared, all of which withstood pressure drops of at least 5000 psi (345 bar). The fritless nature of the columns allows a unique mass production capability whereby long packed columns are entrapped and simply cut afterward. Since the material has previously been shown to be a proficient nanoelectrospray emitter, the columns have enormous potential for use in capillary LC‐MS. The evaluation suggests that for the designs that have minimal entrapped regions, the column performance is equivalent to commercial columns containing similar particles.
Clinical Utility of an Automated Pupillometer for Assessing and Monitoring Recipients of Liver Transplantation
Authors: Yan Sheng , Tu Zhenhua , Lu Weifeng , Zhang Qiyi , He Jiangjuan , Li Zhiwei , Shao Yi , Wang Weilin , Zhang Min , Zheng Shusen
Published: November 2009

Pupil examination has been used as a basic measure in critically ill patients and has great importance for the prognosis and management of disease. An automated pupillometer is a computer-based infrared digital video system by which the accuracy and precision of the pupil examination are markedly improved. We conducted an observational study of pupil assessment with automated pupillometry in clinical liver transplantation settings, including pretransplant evaluations and posttransplant surveillance. Our results showed that unconscious patients (grade 4 hepatic encephalopathy) had a prolonged latency phase (left side: 283 ± 80 milliseconds; right side: 295 ± 96 milliseconds) and a reduced pupillary constrictive ratio (left direct response: 0.23 ± 0.10; left indirect response: 0.21 ± 0.07; right direct response: 0.20 ± 0.08; right indirect response: 0.21 ± 0.08) in comparison with normal and conscious patients. After liver transplantation, the recovery of pupillography in these patients was slower than that in conscious patients. However, the surviving recipients without major complications all had a gradual recovery of pupillary responses, which occurred on the first or second posttransplant day. We also reported 4 cases of futile LT in the absence of pretransplant pupillary responses and other pupillary abnormalities revealed by automated pupillometry in our study. In conclusion, patients with grade 4 hepatic encephalopathy had a sluggish pupil response and a delayed recovery pattern after LT. An automated pupillometer is potentially a supplementary device for pretransplant screening and posttransplant monitoring in patients undergoing LT, but further prospective studies are required. Liver Transpl 15: 1718-1727, 2009. © 2009 AASLD.
Endovascular Closure of a Hemiportocaval Shunt After Small-for-Size Adult-to-Adult Left Lobe Living Donor Liver Transplantation
Authors: Botha Jean F. , Campos Daniel B. , Johanning Jason , Mercer David , Grant Wendy , Langnas Alan
Published: November 2009

Adult-to-adult living donor liver transplantation is an accepted treatment option for patients with end-stage liver disease. It is generally acknowledged that a graft weight to recipient body weight ratio > 0.8 is required in order to prevent the development of small-for-size syndrome. Size mismatch, however, is not the only factor responsible for the syndrome; instead, it results from a combination of factors, including the size, recipient status, and degree of portal hypertension. The ability to modulate the portal venous inflow has sparked renewed interest in the left lobe graft. We have used the hemiportocaval shunt, as described by Troisi et al. (Am J Transplant 2005;5:1397-1404), in left lobe living donor liver transplants in order to prevent small-for-size syndrome while enhancing the safety of the donor operation. In this report, we describe a novel technique for occluding a hemiportocaval shunt in a patient who developed hepatic encephalopathy after receiving a small-for-size left lobe liver allograft from a living donor. Liver Transpl 15:1671-1675, 2009. © 2009 AASLD.
Comparative Prospective Study of Two Liver Graft Preservation Solutions
Authors: Lopez-Andujar Rafael , Deusa Saulo , Montalvá Eva , San Juan Fernando , Moya Angel , Pareja Eugenia , DeJuan Manuel , Berenguer Marina , Prieto Martín , Mir Jose
Published: November 2009

University of Wisconsin solution (UWS) is the gold standard for graft preservation. Celsior solution (CS) is a new solution not as yet widely used in liver grafts. The aim of this study was to compare the liver function of transplanted grafts stored in these 2 preservation solutions. The primary endpoints were the rates of primary nonfunction (PNF) and primary dysfunction (PDF). We performed a prospective and pseudorandomized study that included 196 patients (representing 104 and 92 livers preserved in UWS and CS, respectively) at La Fe University Hospital (Valencia, Spain) between March 2003 and May 2005. PNF and PDF rates, liver function laboratory parameters, postoperative bleeding, vascular and biliary complications, and patient and graft survival at 3 years were compared for the 2 groups. The 2 groups were similar in terms of donor variables, recipient variables, and surgical techniques. The PNF rates were 2.2% and 1.9% in the CS and UWS groups, respectively (P = not significant), and the PDF rates were 15.2% and 15.5% in the CS and UWS groups, respectively (P = not significant). There were no significant differences in the laboratory parameters for the 2 groups, except for alanine aminotransferase levels in month 3, which were lower in the CS group (P = 0.01). No significant differences were observed in terms of complications. Three-year patient and graft survival rates were as follows for years 1, 2, and 3: 83%, 80%, and 76% (patient) and 80%, 77%, and 73% (graft) for the UWS group and 83%, 77%, and 70% (patient) and 81%, 73%, and 67% (graft) for the CS group (P = not significant). In conclusion, this study shows that CS is as effective as UWS in liver preservation. Liver Transpl 15:1709-1717, 2009. © 2009 AASLD.
Impact of Sirolimus on the Recurrence of Hepatocellular Carcinoma After Liver Transplantation
Authors: Chinnakotla Srinath , Davis Gary L. , Vasani Sugam , Kim Peter , Tomiyama Koji , Sanchez Edmund , Onaca Nicholas , Goldstein Robert , Levy Marlon , Klintmalm Göran B.
Published: November 2009

Tumor recurrence after liver transplantation for hepatocellular carcinoma is associated with a poor prognosis. Because immunosuppression is a well-known risk factor for tumor growth, it is surprising that its possible role in the outcome of liver transplantation has been poorly evaluated. We performed a case-control review of prospectively collected data and compared 2 groups of patients according to the type of immunosuppression after liver transplantation for hepatocellular carcinoma at a single center. One hundred six patients received tacrolimus and mycophenolate mofetil, and 121 received sirolimus. Patients in the sirolimus group had significantly higher recurrence-free survival rates than patients in the tacrolimus group (P = 0.0003). The sirolimus group also had significantly higher patient survival rates than the tacrolimus group at 1 year (94% versus 79%), 3 years (85% versus 66%), and 5 years (80% versus 59%; P = 0.001). Sirolimus was well tolerated, and the patients in this study did not have the increase in surgical complications noted by other investigators. Leukopenia was the most common side effect, but it typically resolved with dose reduction. Dyslipidemia and mouth ulcers were common but were easily controlled. In summary, the data suggest a beneficial effect of sirolimus immunosuppression on recurrence-free survival, which translates into patient survival benefits. Liver Transpl 15:1834-1842, 2009. © 2009 AASLD.
A Graft to Body Weight Ratio Less Than 0.8 Does Not Exclude Adult-to-Adult Right-Lobe Living Donor Liver Transplantation
Authors: Selzner Markus , Kashfi Arash , Cattral Mark S. , Selzner Nazia , Greig Paul D. , Lilly Les , McGilvray Ian D. , Therapondos George , Adcock Lesley E. , Ghanekar Anand , Levy Gary A. , Renner Eberhard L. , Grant David R.
Published: November 2009

Many centers require a minimal graft to body weight ratio (GBWR) ≥ 0.8 as an arbitrary threshold to proceed with right-lobe living donor liver transplantation (RL-LDLT), and there is often hesitancy about transplanting lower volume living donor (LD) liver grafts into sicker patients. The data supporting this dogma, based on the early experience with RL-LDLT at Asian centers, are weak. To determine the effect of LD liver volume in the modern era, we investigated the impact of GBWR on the outcome of RL-LDLT with a GBWR as low as 0.6 at the University of Toronto. Between April 2000 and September 2008, 271 adult-to-adult RL-LDLT procedures and 614 deceased donor liver transplants were performed. Twenty-two living donor liver transplantation (LDLT) cases with a GBWR of 0.59 to 0.79 (group A) were compared with 249 LDLT cases with a GBWR ≥ 0.8 (group B) and with 66 full-graft deceased donor liver transplants (group C), who were matched 3:1 according to donor and recipient age, Model for End-Stage Liver Disease score, and presence of hepatitis C and hepatocellular carcinoma with the low-GBWR group. Portal vein shunts were not used. Markers of reperfusion injury [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)], graft function (international normalized ratio and bilirubin), complications graded by the Clavien score, and graft and patient survival were compared. As expected, LD recipients had a significantly shorter cold ischemia time (94 ± 43 minutes for A, 96 ± 57 minutes for B, and 453 ± 152 minutes for C, P = 0.0001). However, the peak AST, peak ALT, absolute decrease in the international normalized ratio, day 7 bilirubin level, postoperative creatinine clearance, complication rate graded by the Clavien score, and median hospital stay were similar in all groups. The rate of biliary complications was higher with LD grafts than deceased donor grafts (19% for A versus 10% for B and 0% for C, P = 0.2). Patient survival was similar in all groups at 1, 3, and 5 years (91% for A versus 89% for B and 93% for C at 1 year, 87% for A versus 81% for B and 89% for C at 3 years, and 83% for A versus 81% for B and 87% for C at 5 years, P = 0.63). A Cox proportional regression analysis revealed only hepatitis C virus as a risk factor for poorer graft survival and not GBWR as a continuous or categorical variable. In conclusion, we found no evidence of inferior outcomes with smaller size grafts versus larger size LD grafts or full-size deceased donor grafts. Further studies are warranted to examine the factors affecting the function of smaller grafts for living liver donation and thereby define the safe lower limits for transplantation. Liver Transpl 15:1776-1782, 2009. © 2009 AASLD.
Rapid Synthesis and MALDI‐ToF Characterization of Poly(ethylene oxide) Multiarm Star Polymers
Authors: Doycheva Maria , Berger‐Nicoletti Elena , Wurm Frederik , Frey Holger
Published: November 2009

Multiarm PEO star polymers with a purely aliphatic polyether structure have been synthesized using hyperbranched polyglycerol (PG) with different molecular weights as a multifunctional initiator. Different degrees of deprotonation of the initiator were studied with respect to molecular weight control. The results show that the degree of deprotonation is a crucial parameter for the synthesis of well‐defined polymers with controlled molecular weights. Partial deprotonation of the PG hydroxyl groups (5–8%) was proven to represent an optimum for the synthesis of star polymers with molecular masses close to the theoretical values. Molecular weights of the stars ranged between 9 000 and 30 000 g · mol−1. MALDI‐ToF spectra confirmed that the PEO arms in the star polymers possess homogeneous lengths.

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Behavior of Deformed Droplets in an Immiscible Polymer Blend: A Comparative Study of Electron Microscopy and Small‐Angle X‐Ray Scattering
Authors: Starý Zdeněk , Baldrian Josef , Stará Hana
Published: November 2009

The deformation of dispersed droplets in a PS/LLDPE 95:5 blend during uniaxial elongation and after cessation of the flow was studied. The behavior of the dispersed droplets during elongation is in a good agreement with a prediction of the modified capillary number model using transient elongational viscosities. The phase structure changes after the elongation was studied in relaxation and recovery modes. The morphology was investigated using scanning electron microscopy and small‐angle X‐ray scattering. Thus the dimensions of the dispersed particles and their degree of orientation were estimated. It was shown that the SAXS as an integral method gives new additional information which is hardly accessible by SEM as a method providing local information about discrete locations in the sample. The results of both methods proved that the stress in the sample is a decisive parameter determining the morphology development after cessation of the flow.

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Effects of Freezing/Thawing Cycles and Cellulose Nanowhiskers on Structure and Properties of Biocompatible Starch/PVA Sponges
Authors: Wang Yixiang , Chang Chunyu , Zhang Lina
Published: November 2009

Strong honeycomb like nanocomposite sponges were fabricated from starch and PVA by using repeated cycles of freezing and thawing and reinforcing with cellulose whiskers. Their structure and properties were investigated with WAXD, FT‐IR, SEM, DMTA, rheological measurements, and LSCM. The results revealed that the repeated freezing/thawing cycles induced a physically crosslinked chain packing between starch and PVA, as well as a phase separation caused by the crystalline ice and syneresis. Thus, larger pores and tougher walls emerged in the sponges, leading to a high swelling degree. The sponges reinforced with cellulose whiskers exhibited improved dimensional stability and enhanced strength. These nanocomposite sponges are promising for wound dressing and tissue engineering applications.

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Effect of the Hierarchical Structure in Poly(propylene)/Clay Composites on their Thermal Stability: From Single‐ to Multi‐Step Degradation Processes
Authors: Palza Humberto , Yazdani‐Pedram Mehrdad
Published: November 2009

Composites with several hierarchical structures were prepared by using different clays, compatibilizers, and PPs. TGA showed that the thermal stability of the composites can be strongly improved, under either inert or thermo‐oxidative conditions, depending on the type of clay and its morphology. Drastic increases in the temperature of the maximum rate of weight loss (ΔTpeak ≈ 170 °C) under thermo‐oxidative conditions were observed depending on the clay dispersion. Furthermore, some composites had a complex multi‐step degradation behavior instead of a single‐step process related with different clay morphologies that can be present simultaneously. Finally, it was concluded that the TGA has a higher sensitivity toward the composite morphology than the mechanical properties.

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Tailoring Polymeric Hydrogels through Cyclodextrin Host–Guest Complexation
Authors: Guo Xuhong , Wang Jie , Li Li , Pham Duc‐Truc , Clements Philip , Lincoln Stephen F. , May Bruce L. , Chen Qingchuan , Zheng Li , Prud'homme Robert K.
Published: November 2009

A close correllation between molecular‐level interactions and macroscopic characteristics of polymer networks exists. The characteristics of the polymeric hydrogels assembled from β‐cyclodextrin (β‐CD) and adamantyl (AD) substituted poly(acrylate)s can be tailored through selective host–guest complexation between β‐CD and AD substituents and their tethers. Dominantly, steric effects and competitive intra‐ and intermolecular host–guest complexation are found to control poly(acrylate) isomeric inter‐strand linkage in polymer network formation. This understanding of the factors involved in polymeric hydrogel formation points the way towards the construction of increasingly sophisticated biocompatible materials.

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Electrospinning of Polyaniline/Poly(Lactic Acid) Ultrathin Fibers: Process and Statistical Modeling using a Non‐Gaussian Approach
Authors: Picciani Paulo H. S. , Soares Bluma G. , Medeiros Eliton S. , de Souza Fernando G. , Wood Delilah F. , Orts William J. , Mattoso Luiz H. C.
Published: November 2009

Fibers of poly(lactic acid) (PLA) blended with p‐toluenesulfonic acid‐doped polyaniline, PAni.TSA, were obtained by electrospinning, following a factorial design which was used mainly to study the effect of four process parameters (PLA solution concentration, PAni solution concentration, applied voltage, and flow rate) on fiber diameter. Due to the non‐Gaussian spread of the fiber diameters, probability density functions (PDF's) were used to describe them, and the main effect analysis was performed considering the most representative values of these PDF's. This study suggests that the main factor which governs the fiber dimension is the concentration of the PAni solution and its synergy with the others factors. Furthermore, in spite of the high complexity of the electrospinning process, the statistical model was able to describe the process with 95% confidence, therefore enabling one to precisely predict fiber diameter. Nanofiber formation was simulated using the results of the experimental design and validation tests were performed to minimize the fiber diameter.

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Complete 1H and 13C NMR data assignment of new constituents from Severinia buxifolia
Authors: Bacher Markus , Brader Günter , Greger Harald , Hofer Otmar
Published: November 2009

Phytochemical analysis of different organs of the rutaceaeous plant Severinia buxifolia led to the isolation of a new limonoid, a new acridone alkaloid, and a new flavone. Structure elucidation and signal assignment were achieved by the extensive use of 1D and 2D NMR experiments (selective 1D NOE, COSY, NOESY, HSQC, HMBC). Copyright © 2009 John Wiley & Sons, Ltd.
A new support integration scheme for the weakform in mesh‐free methods
Authors: Liu Yan , Belytschko Ted
Published: November 2009

A new support integration technique is proposed, which is similar to those used in truly mesh‐free methods. The contribution of this paper is to exploit the divergence‐free condition for the support integrals to construct quadrature formulas that only require three integration points per particle in two dimensions. Numerical examples show that the proposed integration method can achieve results that agree with manufactured closed‐form solutions. Copyright © 2009 John Wiley & Sons, Ltd.
Self‐regularized pseudo time‐marching schemes for structural system identification with static measurements
Authors: Banerjee B. , Roy D. , Vasu R. M.
Published: November 2009

We explore the application of pseudo time marching schemes, involving either deterministic integration or stochastic filtering, to solve the inverse problem of parameter identification of large dimensional structural systems from partial and noisy measurements of strictly static response. Solutions of such non‐linear inverse problems could provide useful local stiffness variations and do not have to confront modeling uncertainties in damping, an important, yet inadequately understood, aspect in dynamic system identification problems. The usual method of least‐square solution is through a regularized Gauss–Newton method (GNM) whose results are known to be sensitively dependent on the regularization parameter and data noise intensity. Finite time, recursive integration of the pseudo‐dynamical GNM (PD‐GNM) update equation addresses the major numerical difficulty associated with the near‐zero singular values of the linearized operator and gives results that are not sensitive to the time step of integration. Therefore, we also propose a pseudo‐dynamic stochastic filtering approach for the same problem using a parsimonious representation of states and specifically solve the linearized filtering equations through a pseudo‐dynamic ensemble Kalman filter (PD‐EnKF). For multiple sets of measurements involving various load cases, we expedite the speed of the PD‐EnKF by proposing an inner iteration within every time step. Results using the pseudo‐dynamic strategy obtained through PD‐EnKF and recursive integration are compared with those from the conventional GNM, which prove that the PD‐EnKF is the best performer showing little sensitivity to process noise covariance and yielding reconstructions with less artifacts even when the ensemble size is small. Copyright © 2009 John Wiley & Sons, Ltd.
Developing a measurement approach for reputation of non‐profit organizations
Authors: Sarstedt Marko , Schloderer Matthias Peter
Published: November 2009

As a result of the increasing adoption of private sector firms' values and concepts, non‐profit organizations (NPOs) are becoming more and more aware of intangible assets' importance for achieving competitive advantages. Even though reputation can be considered an organization's central intangible asset, there is still no appropriate measurement approach for reputation in this context. In this paper, we identify the dimensions of NPO reputation and develop indices to measure these components. We develop a model by means of a qualitative inquiry and a quantitative study using a large‐scale sample from the German general public. We find support for a two‐dimensional measurement approach comprising an affective and cognitive component as well as four antecedent constructs (“quality,” “performance,” “organizational social responsibility (OSR),” and “attractiveness”). The results of a second quantitative study in which we examine NPO reputation's relationship with important outcome variables, such as willingness to donate or work as an honorary member, provide support for the measurement approach's stability as well as criterion validity. Furthermore, the results reveal the affective dimension's importance regarding positively influencing donor behavior.

Copyright © 2009 John Wiley & Sons, Ltd.
Effects of loading rate on viscoplastic properties of polymer geosynthetics and its constitutive modeling
Authors: Peng Fang‐Le , Li Fu‐Lin , Tan Yong , Kongkitkul Warat
Published: November 2009

On the basis of the special tensile test results under various loading histories, the rate‐dependent behaviors of three polymer geosynthetics due to their viscous properties have been investigated. All the investigated polymer geosynthetics show significant loading rate effects, creep deformation, and stress relaxation. Except for the polyester geogrid showing the combined viscosity, all the investigated polymer geosynthetics exhibit the isotach viscosity. An elasto‐viscoplastic constitutive model described in a nonlinear three‐component model framework is developed to simulate the rate‐dependent behaviors of polymer geosynthetics. The developed constitutive model is verified by comparing its simulated results with the experimental data of polymer geosynthetics presented in this study and those available from the literature. The comparison indicates that the developed model can reasonably interpret the rate‐dependent behaviors of polymer geosynthetics under arbitrary loading histories, including the step‐changed strain rate loading, creep, and stress relaxation applied during otherwise monotonic loading (ML). POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Synthesis and light‐emitting properties of carbazole‐based copolymers bearing cyano‐substituted arylenevinylene chromophore
Authors: Takagi Koji , Nakagawa Tsuyoshi , Takao Hidenobu
Published: November 2009

Two arylenevinylene compounds bearing the cyano group at α‐position (6) and β‐position (9) from the dialkoxylphenylene unit were synthesized, in which the molecular termini were functionalized with 3‐bromocarbazole. The Suzuki coupling copolymerization of these compounds with 1,4‐bis[(3′‐bromocarbazole‐9′‐yl)methylene]‐2,5‐didecyloxybenzene and 9,9‐dihexylfluorene‐2,7‐bis(boronic acid) was carried out to obtain copolymers (cp67 and cp97) containing the cyano‐substituted arylenevinylene fluorophore of 7 mol %. Model compounds (6′ and 9′) corresponding to the arylenevinylene fluorophore were also prepared. The UV spectra of copolymers resembled that of homopolymer hp with no arylenevinylene segment in both CHCl3 solution and thin film. The emission maxima of copolymers in CHCl3 (394 nm) agreed with that of homopolymer indicating that the emission bands originated from the carbazole‐fluorene‐carbazole segment. The emission maximum wavelength of copolymer cp67 in thin film (477 nm) indicated fluorescence from the cyano‐substituted arylenevinylene fluorophore because of the occurrence of fluorescence resonance electron transfer. In contrast, copolymer cp97 showed fluorescence at 528 nm to suggest the formation of a new emissive species such as a charge‐transfer complex (exciplex). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 91–98, 2010
Crystallization behavior of clay nanocomposites prepared from a degradable alternating copolyester constituted by glycolic acid and 6‐hydroxyhexanoic acid
Authors: Morales Laura , Franco Lourdes , Casas MarÍA Teresa , PuiggalÍ Jordi
Published: November 2009

An exfoliated nanocomposite was prepared by the film‐casting technique from C25A organo‐modified clay and a new biodegradable polyester derived from glycolic acid and 6‐hydroxyhexanonoic acid. This polyester has a sequential monomer distribution and high crystallinity, allowing a detailed study of its isothermal crystallization. The influence of the clay on the crystallization behavior was investigated by optical microscopy, simultaneous SAXS/WAXD synchrotron radiation and FTIR spectroscopy. Primary nucleation and crystal growth rate decreased significantly with the incorporation of nanoparticles. In addition, the overall crystallization rate of the nanocomposite was logically lower than that of the neat polyester. Bulk crystallizations were modeled from FTIR data with the Avrami equation. The results showed spherulite growth geometry and predetermined (heterogeneous) nucleation for both samples. Morphological studies revealed that both the crystal and the amorphous layer thicknesses were influenced by the presence of silicate layers. The overall percentage of crystallinity and the size of crystalline domains decreased with the addition of the highly miscible organoclay. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 33–46, 2010
Self‐organization of InAs and As quantum dots in GaAs by a combined molecular beam epitaxy process
Authors: Chaldyshev V. V. , Bert N. A. , Nevedomsky V. N. , Preobrazhenskii V. V. , Putyato M. A. , Semyagin B. R.
Published: November 2009

We show a possibility to self‐organize InAs semiconductor quantum dots (SQDs) and As semimetal quantum dots (MQDs) in a close vicinity to each other in the GaAs matrix. For that we develop a combined process of the molecular beam epitaxy (MBE), in which self‐organization of the InAs SQDs was achieved in the Stranski‐Krastanow mode, whereas self‐organization of the As MQDs was realized by the low‐temperature MBE with the subsequent anneal. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence spectra of CdSe/ZnSe double layers of quantum dots
Authors: Reznitsky Alexander , Klochikhin Albert , Permogorov Sergei , Korenev Vladimir V. , Sedova Irina , Sorokin Sergey , Sitnikova Alla , Ivanov Sergei
Published: November 2009

We have studied the emission spectra and structural properties of double CdSe/ZnSe quantum dot (QD) sheet structures grown by molecular beam epitaxy in order to elucidate the mechanisms of the electronic and strain field interaction between the QD planes. The thickness of the ZnSe barrier separating the CdSe sheets was in the range of 10‐60 monolayers (ML) in the set of samples studied. We have found that coupling between dots in adjacent layers becomes relatively strong in CdSe/ZnSe double layers structures with 25‐27 ML barrier, while it is rather weak when the barrier thickness exceeds 30 ML. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron and phonon dynamics in zincblende gallium nitride
Authors: Brazis R. , Raguotis R.
Published: November 2009

This report presents new Monte Carlo simulation results revealing the ballistic stage of growth of the phonon number, electron velocity and energy upon the switching‐on electric field, the shape of electron and phonon stationary distributions in high electric fields, as well as electron cooling and phonon number relaxation rates after switching‐off the field in zincblende gallium nitride crystals.

LO phonon band population inversion is feasible here up to the room temperature relative to the TO phonons, and below T < 80 K – relative to the LA‐phonon band provided that the phonon lifetimes satisfy the conditions of ≥ 2 ps (LO) and ≥ 2 ns (LA). Phonon decay scenarios with the stimulated emission of infrared‐range photons are discussed including phonon difference transitions. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Topic modeling for OLAP on multidimensional text databases: topic cube and its applications
Authors: Zhang Duo , Zhai ChengXiang , Han Jiawei , Srivastava Ashok , Oza Nikunj
Published: November 2009

As the amount of textual information grows explosively in various kinds of business systems, it becomes more and more desirable to analyze both structured data records and unstructured text data simultaneously. Although online analytical processing (OLAP) techniques have been proven very useful for analyzing and mining structured data, they face challenges in handling text data. On the other hand, probabilistic topic models are among the most effective approaches to latent topic analysis and mining on text data. In this paper, we study a new data model calledtopic cubeto combine OLAP with probabilistic topic modeling and enable OLAP on the dimension of text data in a multidimensional text database. Topic cube extends the traditional data cube to cope with a topic hierarchy and stores probabilistic content measures of text documents learned through a probabilistic topic model. To materialize topic cubes efficiently, we propose two heuristic aggregations to speed up the iterative Expectation‐Maximization (EM) algorithm for estimating topic models by leveraging the models learned on component data cells to choose a good starting point for iteration. Experimental results show that these heuristic aggregations are much faster than the baseline method of computing each topic cube from scratch. We also discuss some potential uses of topic cube and show sample experimental results. Copyright © 2009 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 2: 378‐395, 2009
The Role of Rapid Pacu Parathyroid Hormone in Reducing Post‐Thyroidectomy Hypocalcemia
Authors: Sabour Sarmad , Manders Ernest , Steward David L.
Published: November 2009

OBJECTIVES

Post‐thyroidectomy parathyroid hormone (PTH) levels have been used to predict hypocalcemia. The goal of this study was to determine whether selective supplementation for post anesthesia care unit (PACU) PTH < 15 mg/dL reduced hypocalcemia compared to observation or routine supplementation.

STUDY DESIGN

Controlled cohort study of thyroidectomy patients, with chart review.

SETTING

Chart review of total or completion thyroidectomy patients in an academic setting.

SUBJECTS AND METHODS

The control group consisted of 124 subjects. The selective supplementation group consisted of 169 subjects with routine PACU PTH testing. The routine supplementation group consisted of 155 subjects with immediate postoperative calcium and vitamin D supplementation. The control group received supplementation for hypocalcemia (calcium < 8.0 mg/dL). The selective PTH group received calcium and vitamin D supplementation for PACU PTH < 15 mg/dL or hypocalcemia. The routine supplementation group received oral calcium and calcitriol supplementation immediately after surgery. Four separate postoperative day 1 (POD1) outcome measures were evaluated: 1) mean serum calcium; 2) rate of hypocalcemia < 8 mg/dL; 3) rate of significant hypocalcemia < 7.5 mg/dL; and 4) rate of hypercalcemia > 10 mg/dL.

RESULTS

Mean serum calcium was lower and the rate of hypocalcemia was higher in the control group than the selective PACU PTH group on POD1 (8.2 vs 8.6 mg/dL, P < 0.0001, and 35% vs 14%, P < 0.0001, respectively). Mean serum calcium was higher (8.9 vs 8.6 mg/dL, P < 0.0001) and the rate of hypocalcemia lower in the routine supplementation group than in the selective group. However, the rate of hypercalcemia was higher in the routine supplementation group than in the selective group (4.5% vs 0%, P = 0.006).

CONCLUSION

Routine PTH testing and supplementation for patients with hypoparathyroidism reduced the proportion of patients experiencing hypocalcemia. However, supplementation for intraoperative PTH < 15 mg/dL had a higher rate of hypocalcemia than routine supplementation, but with a lower rate of hypercalcemia.
Fluid Residuals and Drug Exposure in Nasal Irrigation
Authors: Harvey Richard J. , Debnath Nick , Srubiski Aviva , Bleier Ben , Schlosser Rodney J.
Published: November 2009

OBJECTIVE

Topical treatment options in chronic rhinosinusitis (CRS) are growing with our increased understanding of the inflammatory process. Additives to irrigation devices have become popular. Additives such as menthol provide little more than sensory feedback. However, glucocorticosteroids and antibiotics represent powerful pharmaceutical agents for which we have little knowledge regarding patient exposure and absorption. There is little data on fluid retained after nasal irrigation. The purpose of this study was to determine the residual volume and percentage of total nasal irrigation that is retained from a neti pot (NasaFlo) or squeeze bottle (Sinus Rinse).

STUDY DESIGN

Cross‐sectional study.

SETTING

Tertiary rhinologic clinic.

METHODS

Patients with CRS were already using saline irrigation in their treatment. Participants were divided into pre and post sinus surgery (ESS). Control irrigations on 17 healthy patients with no sinonasal complaints were collected. Nasal irrigation was performed with accurate collection of the excess to determine retained amount.

RESULTS

Overall retention of fluid was 2.5 ± 1.6 percent. This represents only 5.8 ± 3.8 mL for the 240‐mL irrigations. Squeeze bottle and neti pot were similar: 2.3 ±1.3 percent and 3.0 ± 2.2 percent, respectively (P = 0.23). CRS (pre‐ESS) patients had the least retained volume: 1.4 ± 1.2 percent. Post‐ESS retained volume was 2.36 ± 1.18 percent. Control patients retained 2.2 ± 1.2 percent.

CONCLUSIONS

Quantification of the residual volume has important implications for the treatment of inflammatory disease with saline, as well as for potentially novel topical therapies. The information helps to define the fluid dynamics during nasal irrigation. The data are important to address concerns regarding drug or salt exposure from a very common intervention.
Immunologic Response to Fungus is not Universally Associated with Rhinosinusitis
Authors: Orlandi Richard R. , Marple Bradley F. , Georgelas Ann , Durtschi Drew , Barr Lucy
Published: November 2009

OBJECTIVE

Immunologic response to fungal antigens has been cited as an etiologic factor in chronic rhinosinusitis (CRS). Previous work demonstrated a significant cytokine response in CRS patients that did not correlate with an immunoglobulin E (IgE) response. This study was performed in an effort to replicate these findings in a more geographically diverse population.

DESIGN

Prospective in vitro study.

SETTING

Two academic tertiary rhinologic practices in Texas and Utah.

METHODS

Serum and peripheral blood monocytes (PBMC) were obtained from 10 CRS patients and seven controls. Total IgE and fungal‐specific IgE levels were determined. Cytokine levels were measured after PBMC exposure to Alternaria, Aspergillus, Cladosporium, and Penicillium extracts. Correlations between cytokine responses and presence of CRS as well as IgE and IgG were determined.

RESULTS

Interleukin‐5 (IL‐5) was produced after Alternaria extract exposure in both CRS patients and controls, but the production was heterogenous and did not correlate with the presence of CRS. IL‐5 levels after Alternaria extract exposure correlated strongly with levels of Alternaria‐specific IgE in both CRS patients and controls. IL‐5 production did not correlate with IgG levels. IL‐4, IL‐13, and interferon‐gamma production did not differ between CRS patients and controls.

CONCLUSIONS

In contrast to previously reported data, IL‐5 responses to Alternaria extract were not predictive of CRS presence. Our results in patients from Utah and Texas significantly differ from previously published findings in predominantly Midwestern patients. The immunologic response to fungal extracts appears to be heterogenous and may differ based on geography, allergy status, and/or other as‐yet unknown factors.
Effect of overweight on gastrointestinal microbiology and immunology: correlation with blood biomarkers
Authors: Tiihonen Kirsti , Ouwehand Arthur C. , Rautonen Nina
Published: November 2009

A cross-sectional study was carried out in order to compare intestinal microbiological and immunological biomarkers with blood glucose and lipids, satiety-related hormones and inflammatory biomarkers characterising differences between obese and normal weight subjects. Faecal and blood samples were obtained from twenty obese subjects with an average BMI of 32·9 kg/m2and twenty normal weight subjects with an average BMI of 23·3 kg/m2. Blood insulin, TAG and leptin were significantly elevated, whereas concentrations of HDL and ghrelin were significantly decreased in the obese subjects. Inflammatory status in the obese subjects was characterised by a trend for elevated blood C-reactive protein (CRP;P = 0·06) and IL-6 (P = 0·02). The faecal microbial composition differed between the groups; less sulphate-reducing bacteria (P = 0·05) and a trend for lessBacteroides(P = 0·07) were measured for overweight subjects. Furthermore, an inverse correlation was demonstrated between faecalBacteroideslevels and waist circumference (P = 0·05). The faecal microbial metabolites differed between the groups; increased concentrations of branched-chain fatty acids, phenolics, valeric acid, di- and hydroxy acids were described in the obese subjects. No differences between the measured intestinal inflammatory biomarkers were detected. However, systemic inflammation (CRP and IL-6) was correlated with the faecal concentrations of phenolics and lactic acid (P < 0·05 and 0·05, andP < 0·01 and 0·05, respectively). In summary, weight-related differences were observed both in the intestinal microbial composition and its activity. The role of intestinal signals, such as phenolics and lactic acid in the development of weight-related problems, needs to be studied further.
Grape antioxidant dietary fibre reduced apoptosis and induced a pro-reducing shift in the glutathione redox state of the rat proximal colonic mucosa
Authors: López-Oliva María Elvira , Agis-Torres Angel , Goñi Isabel , Muñoz-Martínez Emilia
Published: November 2009

Grape antioxidant dietary fibre (GADF) is a grape product rich in dietary fibre and natural antioxidants. We showed previously that the GADF intake induced an epithelial hypoplasia in the rat colonic mucosa. In the present study, we propose that the antioxidant effect of GADF could modulate mucosal apoptosis via modulation of the cellular redox environment. Male Wistar rats (n20) were fed with diets containing either cellulose (control diet group) or GADF (GADF diet group) as fibre for 4 weeks. The GSH:GSSG ratio, the redox state of the GSSG/2GSH couple (Ehc), the mitochondrial and/or cytosolic antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)), lipid peroxidation (LPO) and apoptosis were evaluated. GADF enhanced the cytosolic GSH:GSSG ratio, shifting the redox potential (Ehc) to a more pro-reducing status. Decreased Cu,ZnSOD:CAT, Cu,ZnSOD:GPx and MnSOD:GPx ratios could indicate an enhanced capacity for reducing H2O2, contributing to decreased cytosolic LPO. Reduced apoptosis in GADF-treated mucosa was inversely related to MnSOD activity. Furthermore, apoptosis increased directly as GSSG content increased. These results suggest that the reduction in apoptosis associated with GADF intake may be due to a modulation of the glutathione redox system and endogenous antioxidant enzymes.
C*-algebras arising from substitutions
Authors: FUJINO MASARU
Published: November 2009

In this paper, we introduce a C*-algebra associated with a primitive substitution. We show that when σ is proper, the C*-algebra is simple and purely infinite and contains the associated Cuntz–Krieger algebra and the crossed product C*-algebra of the corresponding Cantor minimal system. We calculate the K-groups.