bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quality control in urodynamics: Analysis of an international multi‐center study
Authors: Renganathan Arasee , Cartwright Rufus , Cardozo Linda , Robinson Dudley , Srikrishna Sushma 
Published: December 2008

AbstractAimsTo review the quality of urodynamic traces collected as part of a multi‐center Phase II drug trial of a medication for overactive bladder (OAB), in order to assess adherence to the Good Urodynamic Practice (GUP) guidelines. To assess inter‐rater reliability (IRR) for the numerical cystometrogram variables, and for the diagnosis of detrusor overactivity (DO).MethodsTwo central reviewers assessed 50 cystometrograms, recording the presence or absence of DO and assessing compliance with GUP guidelines. Three central reviewers independently assessed 20% of cystometrograms submitted, for numerical variables. IRR of central and peripheral assessments were compared with intra‐class correlation (ICC) and Cohen's unweighted kappa statistics.ResultsThere was inconsistent adherence to GUP guidelines, because of differences in urodynamic equipment and practice. ICC between numerical variables assessed by the three central reviewers were excellent ranging between 0.830 and 0.997 (P all ≤0.001). ICC between numerical variables assessed by peripheral and central reviewers were good to excellent, ranging between 0.624 and 0.994 (P all ≤0.05). Central reviewers showed excellent agreement in the assessment of DO (kappa = 0.83). However central and peripheral reviewers showed poor agreement in the assessment of DO (kappa = 0.24).ConclusionWithout standardization of equipment and training, adherence to GUP guidelines is problematic. Cystometric pressure and volume variables can however be reliably assessed in multi‐center studies. DO cannot be reliably observed by interpreting the cystometrogram trace in isolation. Objective assessment of DO may therefore be unsuitable for multi‐center studies reliant on central reporting of traces. Neurourol. Urodynam. 28:380–384, 2009. © 2008 Wiley‐Liss, Inc.
Competition under time‐varying demands and dynamic lot sizing costs
Authors: Federgruen Awi , Meissner Joern 
Published: December 2008

AbstractWe develop a competitive pricing model which combines the complexity of time‐varying demand and cost functions and that of scale economies arising from dynamic lot sizing costs. Each firm can replenish inventory in each of the T periods into which the planning horizon is partitioned. Fixed as well as variable procurement costs are incurred for each procurement order, along with inventory carrying costs. Each firm adopts, at the beginning of the planning horizon, a (single) price to be employed throughout the horizon. On the basis of each period's system of demand equations, these prices determine a time series of demands for each firm, which needs to service them with an optimal corresponding dynamic lot sizing plan. We establish the existence of a price equilibrium and associated optimal dynamic lotsizing plans, under mild conditions. We also design efficient procedures to compute the equilibrium prices and dynamic lotsizing plans.© 2008 Wiley Periodicals, Inc. Naval Research Logistics 2009
Optimal design of accelerated life testing plans for periodical replacement with penalty
Authors: Liao Haitao 
Published: December 2008

AbstractAccelerated life testing (ALT), enhanced by optimal test plans, has been widely accepted in practice as a quick approach for estimating the reliability of a product. From the estimation result, preventive maintenance schedules can be determined to ensure the performance of the product under its normal operating conditions. By default, maintenance decision‐making is regarded as the last and least rewarding step. However, sometimes the maintenance schedules, such as preventive maintenance intervals, are predetermined due to customer concerns and/or by various mandatory regulations and rules. Under such circumstances, how to accurately estimate the expenditure (e.g., on maintenance or spare parts management) associated with these maintenance requirements becomes an important issue. A viable solution is to incorporate the maintenance requirements into ALT plans. This paper provides an approach for the optimal design of ALT plans oriented by a mandatory periodical replacement schedule subject to a discounted penalty. The objective is to improve the estimation accuracy of the economic impact of this maintenance requirement. A numerical experiment is provided to demonstrate the approach in practical use. © 2008 Wiley Periodicals, Inc. Naval Research Logistics 2009
Models and branch‐and‐cut algorithms for the Steiner tree problem with revenues, budget and hop constraints
Authors: Costa Alysson M. , Cordeau Jean‐François , Laporte Gilbert 
Published: December 2008

AbstractThe Steiner tree problem with revenues, budget and hop constraints is a variant of the Steiner tree problem with two main modifications: (a) besides the costs associated with arcs, there are also revenues associated with the vertices, and (b) there are additional budget and hop constraints, which impose limits on the total cost of the network and on the number of edges between any vertex and the root, respectively. This article introduces and compares several mathematical models for this problem and describes two branch‐and‐cut algorithms, which solve to optimality instances with up to 500 vertices and 625 edges. © 2008 Wiley Periodicals, Inc. NETWORKS, 2009
Approximating the smallest k‐edge connected spanning subgraph by LP‐rounding
Authors: Gabow Harold N. , Goemans Michel X. , Tardos Éva , Williamson David P. 
Published: December 2008

AbstractThe smallest k‐ECSS problem is, given a graph along with an integer k, find a spanning subgraph that is k‐edge connected and contains the fewest possible number of edges. We examine a natural approximation algorithm based on rounding an LP solution. A tight bound on the approximation ratio is 1 + 3/k for undirected graphs with k > 1 odd, 1 + 2/k for undirected graphs with k even, and 1 + 2/k for directed graphs with k arbitrary. Using iterated rounding improves the first upper bound to 1 + 2/k. On the hardness side we show that for some absolute constant c > 0, for any integer k ≥ 2 (k ≥ 1), a polynomial‐time algorithm approximating the smallest k‐ECSS on undirected (directed) multigraphs to within ratio 1 + c/k would imply P = NP. © 2008 Wiley Periodicals, Inc. NETWORKS, 2009
The boundary element method with Lagrangian multipliers
Authors: Gatica Gabriel N. , Healey Martin , Heuer Norbert 
Published: December 2008

AbstractOn open surfaces, the energy space of hypersingular operators is a fractional order Sobolev space of order 1/2 with homogeneous Dirichlet boundary condition (along the boundary curve of the surface) in a weak sense. We introduce a boundary element Galerkin method where this boundary condition is incorporated via the use of a Lagrangian multiplier. We prove the quasi‐optimal convergence of this method (it is slightly inferior to the standard conforming method) and underline the theory by a numerical experiment.The approach presented in this article is not meant to be a competitive alternative to the conforming method but rather the basis for nonconforming techniques like the mortar method, to be developed. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
On a 1D inverse problem with interfaces in bioengineering
Authors: Troparevsky M.I. , Rubio D. 
Published: December 2008

AbstractIn this work we study a 1D Inverse Problem that is motivated by the electroencephalogram (EEG) problem, which consists in the use of EEG data to find the location of electric sources of neural activity in the brain. We analize a 1D differential equation with a unique pointwise source. We consider different source models and study the sensitivity of the solution with respect to a parameter associated with the location of the source. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Identification of muscle determinant for different gait speeds by proper orthogonal decomposition
Authors: Sirisup Sirod , Boonsinsukh Rumpa 
Published: December 2008

AbstractIn this investigation, we explore the use of the proper orthogonal decomposition (POD) on electromyography (EMG) of the leg muscles, with the objective of elucidating the muscles behavior for each gait speeds. Four different gait speeds were used in the study: slow, comfortable, fast and fastest walking. The electromyographic data used in this study were recorded from 12 bilateral lower limb muscles: tensor fascia latae (TFL), semitendinosus (ST), vastus medialis (VM), rectus femoris (RF), tibialis anterior (TA) and medial gastrocnemius (MG). Results indicate that the primary muscles for these gait speeds were bilateral TFL which act alternately to accept weight bearing on each leg. The same muscles also show another dominant function when working simultaneously in pelvic stabilization. In addition, we found that when the speed of walking increases, the number of muscle determinants for gait has been added. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control of a boundary layer separation
Authors: Uruba V. , Knob M. , Popelka L. 
Published: December 2008

AbstractThe results of experimental study on a boundary layer separation control are given in the paper. The boundary layer on a flat wall is subjected to adverse pressure gradient. The active control strategy evolving a synthetic jet has been applied. The separation process is investigated using TR‐PIV method. Dynamical aspects of the phenomenon are analyzed in details. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Integer solution of a set of bilinear equations
Authors: Nowak Michal , Ziólko Mariusz 
Published: December 2008

AbstractAn efficient method for a design of transmultiplexer filters is suggested. The perfect reconstruction conditions lead to the bilinear equations for FIR filters coefficients. The method of solving these equations results from the presented theorem. Usefulness of the algorithm in fixed‐point arithmetic is the crucial issue. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Continuous solutions of some boundary layer problem (Poster Presentation)
Authors: Dreglea Aliona I. , Sidorov Nikolay A. 
Published: December 2008

AbstractThe continuous solutions for BVP of third order nonlinear differential equations appears in [1] mathematical model of the melt spinning process. The existence theorem is proved for such BVP. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis, thermal, and rheological properties of poly(trimethylene terephthalate)/BaSO4 nanocomposites
Authors: Yao Chenguang , Yang Guisheng 
Published: December 2008

AbstractA novel method was developed for fabricating poly(trimethylene terephthalate) (PTT)/BaSO4 nanocomposites using in situ polymerization. A nano‐BaSO4 suspension was prepared by reacting H2SO4 with Ba(OH)2 in 1,3‐propanediol (PDO). The mean size of original nano‐BaSO4 is 15–23 nm. PTT matrix was synthesized by condensation polymerization of bis(3‐hydroxypropyl terephthalate) after the completion of transesterification of dimethyl terephthalate (DMT) with PDO. It was found that the addition of BaSO4 had little influence on the synthesis of PTT. The properties of nanocomposites with a wide range of BaSO4 fraction were systematically studied. The morphologies of the composites were investigated by transmission electron microscopy (TEM), which showed that agglomerate structures did not form until BaSO4 content higher than 8 wt%. The thermal properties of the nanocomposites were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The DSC results revealed that the triple endothermic melting phenomenon is only observed for the nanocomposites which contained 4 wt% BaSO4, other samples exhibit double endothermic melting. These results indicated that nano‐BaSO4 could induce a microcrystal to form more perfect morphology and restrain the formation of much thicker lamellar crystallinity, that is, nano‐BaSO4 could induce the formation of more uniform crystallinity. Besides, the crystallization ability of the composites was greatly improved by loading nano‐BaSO4. The TGA results suggested that nano‐BaSO4 slightly increased the maximum‐decomposing‐rate temperature 1 (Tmax1), but markedly increased the maximum‐decomposing‐rate temperature 2 (Tmax2). Furthermore, the steady‐state shear behavior of samples was investigated by a parallel‐plate rheometer. The storage modulus (G') and loss modulus (G”) curves shifted to higher modulus upon addition of 2–16 wt% of nano‐BaSO4. All of the samples investigated exhibited the expected shear‐thinning behavior. Proper contents of nano‐BaSO4 would decrease the shear viscosity of nanocomposites, whereas superfluous amounts would greatly increase the viscosity of nanocomposites and the composites which loaded 8 wt% nano‐BaSO4 revealed an equivalent shear viscosity compared to pure PTT. Copyright © 2008 John Wiley & Sons, Ltd.
Stem cells in pathobiology and regenerative medicine
Authors: Alison MR 
Published: December 2008

AbstractThis issue of the Journal of Pathology contains 16 articles largely dealing with the role of tissue‐specific adult stem cells in the pathogenesis of disease, notably cancer. These authoritative reviews begin by describing the current knowledge regarding the identity and molecular regulation of normal tissue‐specific stem cells, before itemizing their role in the aetiology and progression of disease. Fundamental concepts regarding the stem cell niche have been gleaned from studies of germ line stem cells in Drosophila and Caenorhabditis elegans, and these are described in detail in this issue. Somatic cell reprogramming, a process underlying not only therapeutic cloning but also the production of induced pluripotent stem (iPS) cells, is further discussed. Much attention is given to embryonic stem (ES) and iPS cells within the scientific community; this issue of the Journal of Pathology redresses this imbalance by illustrating the pivotal role of adult stem cells in much of human disease. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The use of a protein and energy dense eicosapentaenoic acid containing supplement for malignancy‐related weight loss in children
Authors: Bayram Ibrahim , Erbey Fatih , Celik Nilgun , Nelson Jeffrey L. , Tanyeli Atila 
Published: December 2008

AbstractBackgroundThe aim of nutritional therapy in cancer patients is to prevent weight loss and to improve functional capacity and quality of life. Clinical studies however, have continued to demonstrate that a reduction in body weight loss is difficult to achieve in cancer cachexia. Several studies have shown that supplementation with eicosapentaenoic acid (EPA), an omega‐3 fatty acid, has anti‐cachectic effects in adult cancer patients. This study evaluated the clinical effects of a protein and energy dense EPA containing nutritional supplement in a group of pediatric cancer patients receiving active chemotherapy treatment.MethodsThe study was a prospective, randomized, single center, open‐label design. Fifty‐two patients diagnosed with pediatric malignant disease and receiving intensive chemotherapy were included. Thirty‐three patients received a nutritional supplement containing EPA in addition to their regular food intake. Nineteen control patients did not receive supplementation. Patients were examined and their data (body weight, body mass index, and weight percentile) were recorded regularly once a month for 3 months. A subgroup of patients was evaluated for 6 months.ResultsAt 3 months, there were significantly fewer patients in the treatment group as compared to controls that showed losses in body weight (P = 0.001), BMI (P = 0.002), and a negative deviation in weight percentile (P = 0.021). In addition, remission rate was significantly (P = 0.036) higher in the treatment group as compared to controls.ConclusionsThis study demonstrates a decrease in cancer‐induced weight loss in pediatric patients fed a protein and energy dense nutrition supplement containing EPA. Pediatr Blood Cancer 2009;52:571–574. © 2008 Wiley‐Liss, Inc.
Apoptosis‐inducing activity ofHelleborus nigerin ALL and AML
Authors: Jesse Patrick , Mottke Gritt , Eberle Jürgen , Seifert Georg , Henze Günter , Prokop Aram 
Published: December 2008

AbstractBackgroundHelleborus nigeris used in the adjuvant treatment of different tumors in anthroposophical medicine. Indications include various types of brain tumors in children, as well as prostate cancer, leukemia and lymphoma. Our aim was to investigate the therapeutic effects of these extracts apart from the traditional use.Procedures: We used an aqueous whole plant extract ofH. nigerin different cancer and leukemia cell lines and primary cells of patients with childhood ALL and AML and identified the main mechanisms of action.ResultsA strong inhibition of proliferation is caused by specific apoptosis induction, which is executed via the mitochondrial pathway and caspase‐3 processing. Apoptosis could be detected in lymphoma (BJAB), leukemia (Reh, Nalm6, Sup‐B15) and melanoma (Mel‐HO) cells and overcomes a Bcl‐2‐mediated block of apoptosis. In primary cells of patients with childhood ALL and AML, which were partly poor responding to doxorubicin and daunorubicin, a strong apoptosis induction was determined. In combination with the vinca alkaloid vincristine, strong synergistic effects were detected in BJAB cells.ConclusionWe demonstrate in vitro efficacy ofH. nigerextract in cells of hematological malignancies; these studies should encourage in vivo experiments. Pediatr Blood Cancer 2009;52:464–469. © 2008 Wiley‐Liss, Inc.
Mechanical performance of resol type phenolic resin/layered silicate nanocomposites
Authors: Tasan C. Cem , Kaynak Cevdet 
Published: December 2008

AbstractClay addition has been shown to affect polymer resins positively in terms of several physical and chemical properties, including mechanical performance, high temperature endurance and durability. These increases are limited only to relatively low concentrations of reinforcement phase, but at these low concentrations polymer/layered silicate nanocomposites (P/LS NC) have shown to exhibit higher mechanical performance than fiber reinforced polymer composites. This is among the several reasons that make P/LS NC's one of the most widely studied class of materials today. In this study, the mechanical performance of resol type phenolic resin/layered silicate nanocomposite specimens was examined by carrying out 3‐point bending, Charpy impact and fracture toughness tests to couple the observations, microstructural analysis is done through X‐ray diffraction and scanning electron microscopy. The effects of especially three factors; cure method, clay amount, and clay modification were investigated. It was concluded that highest mechanical performance was obtained by the acid curing of the phenolic resin with very low amounts (e.g., 0.5%) of either very hydrophobic or very hydrophilic Na‐montmorillonite clay additions. Improvements as high as 7% in flexural strength, 11% in flexural strain at break, 16% in Charpy impact strength, and 66% in fracture toughness values were obtained. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
The mechanical/thermal properties of microcellular injection‐molded poly‐lactic‐acid nanocomposites
Authors: Hwang Shyh‐Shin , Hsu Peming P. , Yeh Jui‐Ming , Chang Kung‐Chin , Lai Ying‐Zhong 
Published: December 2008

AbstractThis study investigated the influence of montmorillonite (MMT) content on the mechanical/thermal properties of microcellular injection‐molded polylactide (PLA)/clay nanocomposites. Carbon dioxide was the blowing agent. The PLA/MMT nanocomposites were prepared by twin screw extrusion. The results showed that as MMT content is increased, tensile strength, impact strength, and cell density decrease. This is caused by the speed degradation of PLA due to the addition of MMT. MMT decreases the crystallization temperature but increases the decomposition temperature of the nanocomposites. The XRD results showed that the layer spacing of the clay increases as MMT content increases. TEM pictures showed that the MMT is well dispersed within the PLA matrix. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers.
Nanostructured fly ash–styrene butadiene rubber hybrid nanocomposites
Authors: Paul K. Thomas , Pabi S.K. , Chakraborty K.K. , Nando G.B. 
Published: December 2008

AbstractHybrid nanocomposites of styrene butadiene rubber (SBR) with nanostructured fly‐ash (NFA) were prepared in the laboratory by melt blending technique in an internal mixer. Curatives were added on a laboratory two‐roll mill. Curing characteristics as well as physico‐mechanical properties of the composites were evaluated. A comparison on SBR composites filled with fresh fly‐ash (FFA); carbon black (CB) and precipitated silica (PS) has been reported. In general, SBR‐NFA composites exhibit higher state of cure and higher strength properties as compared with HAF black‐filled and fresh fly‐ash‐filled SBR composites at equivalent loadings. This may be attributed to the higher reinforcing ability of NFA. This fact has also been supported by the swelling studies and Kraus' plot. Tear strength and abrasion resistance of the SBR‐NFA composites were superior to FFA‐filled and precipitated silica‐filled vulcanizates, but were inferior to carbon black‐ filled SBR vulcanizates. The SBR‐NFA composites showed lower hardness as compared with both the carbon black‐filled and silica‐filled composites. Transmission electron microscopy and scanning probe microscopy studies revealed that the NFA particles are well dispersed in the SBR matrix. These results were further supported by fracture surface analysis under the SEM, which revealed the role of NFA in the prevention of fracture propagation. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Modified continuous carbon fiber‐reinforced poly(phthalazinone ether sulfone ketone) composites by blending polyetherimide and polyethersulfone
Authors: Zheng Liang , Liao Gong‐Xiong , Gu Tie‐Sheng , Han Yong‐Jin , Jian Xi‐Gao 
Published: December 2008

AbstractPoly(phthalazinone ether sulfone ketone) (PPESK) is a novel high performance thermoplastic with outstanding high temperature resistance and excellent mechanical properties and therefore, it is a very ideal candidate matrix for advanced composites. However, its high melting viscosity makes the melting process difficult. In this article, two well‐known high performance thermoplastics, polyetherimide (PEI) and polyethersulfone (PES) were introduced to PPESK in order to reduce the melting viscosity of PPESK and to improve the properties of composites. The effect of addition of PEI and PES on the resultant composites was studied. A series of unidirectional composites were made of PPESK and its PEI and PES blends as matrix and continuous carbon fiber (T700) as reinforcement. The solution prepregging method and hot‐press molding method were used in preparation of composites. The effects of polymer blends matrix on mechanical properties, interfacial adhesion, and fracture mode were studied by three points bending, interlaminar shearing, porosity, and scanning electron microscope test. The results show that the mechanical properties and interfacial adhesion increases, and the porosity decrease after blending PEI or PES in the matrix. Addition of PEI and PES to PPESK results in an obvious transition of fracture mode. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers