bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of passive systems for control of inelastic structures
Authors: Cimellaro Gian Paolo , Lavan Oren , Reinhorn Andrei M.
Published: November 2008

A design strategy for control of buildings experiencing inelastic deformations during seismic response is formulated. The strategy is using weakened, and/or softened, elements in a structural system while adding passive energy dissipation devices (e.g. viscous fluid devices, etc.) in order to control simultaneously accelerations and deformations response during seismic events. A design methodology is developed to determine the locations and the magnitude of weakening and/or softening of structural elements and the added damping while insuring structural stability. A two‐stage design procedure is suggested: (i) first using a nonlinear active control algorithm, to determine the new structural parameters while insuring stability, then (ii) determine the properties of equivalent structural parameters of passive system, which can be implemented by removing or weakening some structural elements, or connections, and by addition of energy dissipation systems. Passive dampers and weakened elements are designed using an optimization algorithm to obtain a response as close as possible to an actively controlled system. A case study of a five‐story building subjected to El Centro ground motion, as well as to an ensemble of simulated ground motions, is presented to illustrate the procedure. The results show that following the design strategy, a control of both peak inter‐story drifts and total accelerations can be obtained. Copyright © 2008 John Wiley & Sons, Ltd.
New joint frame synchronisation and carrier frequency offset estimation method for OFDM systems
Authors: Zhang Zhongshan , Kayama Hidetoshi , Tellambura Chintha
Published: November 2008

We propose a new joint frame synchronisation and carrier frequency offset estimation scheme for burst transmission mode OFDM systems. This scheme uses a central‐symmetric and comb‐like (CSCL) training sequence, which eases the power detection at the receiver without increasing the total training sequence power. Fine frame synchronisation as well as carrier frequency offset acquisition with a maximum acquisition range of$\pm {{N} \over {4\times {\rm SF}}}$times the sub‐carrier spacing can also be performed based on the proposed CSCL training sequence, whereNis the discrete Fourier transform (DFT) length and SF is an integer‐valuedspreading factorused to generate CSCL. The post‐acquisition residual carrier frequency offset can be further estimated and corrected via a fine adjustment algorithm. In order to reduce performance loss due to the high peak‐to‐average power ratio (PAPR) of the CSCL training sequence, a time‐domain constant‐envelope (CE) training sequence is also proposed. The superior estimation accuracy of the proposed algorithm over that of the Moose algorithm and the SS (Shi and Serpedin) algorithm is proved by computer simulation. Copyright © 2008 John Wiley & Sons, Ltd.
Some results on the accuracy of an edge‐based finite volume formulation for the solution of elliptic problems in non‐homogeneous and non‐isotropic media
Authors: de Carvalho Darlan Karlo Elisiário , Willmersdorf Ramiro Brito , Lyra Paulo Roberto Maciel
Published: November 2008

The numerical simulation of elliptic type problems in strongly heterogeneous and anisotropic media represents a great challenge from mathematical and numerical point of views. The simulation of flows in non‐homogeneous and non‐isotropic porous media with full tensor diffusion coefficients, which is a common situation associated with the miscible displacement of contaminants in aquifers and the immiscible and incompressible two‐phase flow of oil and water in petroleum reservoirs, involves the numerical solution of an elliptic type equation in which the diffusion coefficient can be discontinuous, varying orders of magnitude within short distances. In the present work, we present a vertex‐centered edge‐based finite volume method (EBFV) with median dual control volumes built over a primal mesh. This formulation is capable of handling the heterogeneous and anisotropic media using structured or unstructured, triangular or quadrilateral meshes. In the EBFV method, the discretization of the diffusion term is performed using a node‐centered discretization implemented in two loops over the edges of the primary mesh. This formulation guarantees local conservation for problems with discontinuous coefficients, keeping second‐order accuracy for smooth solutions on general triangular and orthogonal quadrilateral meshes. In order to show the convergence behavior of the proposed EBFV procedure, we solve three benchmark problems including full tensor, material heterogeneity and distributed source terms. For these three examples, numerical results compare favorably with others found in literature. A fourth problem, with highly non‐smooth solution, has been included showing that the EBFV needs further improvement to formally guarantee monotonic solutions in such cases. Copyright © 2008 John Wiley & Sons, Ltd.
Chemokine receptor CXCR4 expression is correlated with VEGF expression and poor survival in soft‐tissue sarcoma
Authors: Oda Yoshinao , Tateishi Naomi , Matono Hiroshi , Matsuura Suguru , Yamamaoto Hidetaka , Tamiya Sadafumi , Yokoyama Ryohei , Matsuda Shuichi , Iwamoto Yukihide , Tsuneyoshi Masazumi
Published: November 2008

The expression of chemokine receptor CXCR4 has been associated with poor prognosis and VEGF expression in several kinds of human malignancy. We measured CXCR4 expression levels in soft‐tissue sarcoma and compared them with VEGF expression or microvessel density (MVD). We used real‐time quantitative PCR to examine the CXCR4 and VEGF expression levels in a total 176 tumors, including 24 intermediate tumors, 24 malignant round‐cell tumors (MRCTs) and 128 malignant non‐round‐cell tumors (MNRCTs). We also assessed their immunohistochemical expression of CXCR4 and VEGF, MVD and proliferative activities, as measured by the MIB‐1‐labeling index (LI). Furthermore, we evaluated their significance with respect to patient survival rates in MNRCTs, using the Cox regression model. Within the different types of tumor tissue, the expression levels of CXCR4 (p < 0.0001) and VEGF (p < 0.0001) in MNRCTs were significantly higher than those in intermediate tumors or MRCTs. Immunohistochemical expression levels of CXCR4 and VEGF were significantly correlated with their mRNA expression levels (p < 0.0001). Significant positive correlation was found between CXCR4 and VEGF expression in 112 primary MNRCTs (r = 0.434, p < 0.0001). Moreover, both univariate (p < 0.0001) and Cox multivariate analysis (p = 0.0001) revealed that overexpression of CXCR4 was an independent adverse prognostic factor, in addition to high stage according to the American Joint Committee on Cancer and a high MIB‐1‐LI. Determination of the CXCR4 expression level as a novel marker can provide useful prognostic information for patients and it could be a candidate for molecular targeting therapy in MNRCTs of soft‐tissue sarcomas. © 2008 Wiley‐Liss, Inc.
Gold(III) porphyrin complex is more potent than cisplatin in inhibiting growth of nasopharyngeal carcinoma in vitro and in vivo
Authors: To Yuk Fai , Sun Raymond Wai‐Yin , Chen Yongxiong , Chan Vera Sau‐Fong , Yu Wing‐Yiu , Tam Paul Kwong‐Hang , Che Chi‐Ming , Lin Chen‐Lung Steve
Published: November 2008

Nasopharyngeal carcinoma (NPC) is a common neoplasm in Southeastern Asia, and cisplatin‐containing regimens for combinational chemotherapy are widely used for treating locally recurrent or metastatic diseases. However, resistance to cisplatin is not infrequently seen and its associated side effects may be life‐threatening. In this report, another metallo‐pharmaceutical agent gold(III) porphyrin complex [Au(TPP)]Cl was investigated in comparison to cisplatin for its in vitro and in vivo anticancer effects. Through induction of the intrinsic apoptosis pathway, [Au(TPP)]Cl exhibited 100‐fold higher potency than cisplatin in killing NPC cells, including cisplatin‐sensitive and cisplatin‐resistant variants, and also an variant harboring the Epstein‐Barr virus. In addition, a safety concentration window was demonstrated, allowing [Au(TPP)]Cl to kill tumors with minimal cytotoxicity to noncancerous cells. More importantly, weekly intraperitoneal injection of 3 mg/kg [Au(TPP)]Cl was more effective than the same dose of cisplatin in inducing tumor apoptosis in vivo and remarkably inhibited tumor growth in animals without any noticeable side effect. [Au(TPP)]Cl therefore is a promising chemotherapeutic agent that deserves further development as a novel drug for the treatment of advanced NPC, in particular, for cases with cisplatin‐resistance. © 2008 Wiley‐Liss, Inc.
Autoimmunity and lymphomagenesis
Authors: Goldin Lynn R. , Landgren Ola
Published: November 2008

For more than 50 years, links between autoimmunity and lymphomas have been described based on human and animal studies. Over the last 3 decades, many studies have addressed specific hypotheses about these associations using population level data. This has been accomplished by assessing previous autoimmune history in case–control studies of patients with lymphoma (mainly non‐Hodgkin lymphoma) and myeloma, and by following cohorts of patients with various autoimmune diseases for subsequent development of lymphoma and multiple myeloma. In this article, we review our recently published series of association studies based on data from Scandinavia and from US Veterans and other relevant findings. We also discuss what these associations have revealed about the mechanisms and pathways underlying both autoimmunity and lymphoma. Finally, we discuss the future directions involving a combination of population and molecular studies that are needed to better define underlying biological mechanisms. Published 2008 Wiley‐Liss, Inc.
Oral administration of diphenyl diselenide potentiates hepatotoxicity induced by carbon tetrachloride in rats
Authors: Nogueira Cristina W. , Borges Lysandro Pinto , Souza Ana Cristina Guerra
Published: November 2008

Carbon tetrachloride (CCl4) is a model for studying free radical‐induced liver injury and screening hepato‐protective drugs. Numerous studies have reported the involvement of oxidative stress in CCl4‐induced liver damage and the hepato‐protective effects mediated by different antioxidants. The present study examined the effects of diphenyl diselenide, (PhSe)2, on hepatotoxicity induced by CCl4 in rats. To this end, male Wistar rats received (PhSe)2 by oral route at the dosage of 31.2 mg/kg for one or two days. After the second day of treatment, rats received CCl4 orally in a single dose. The liver and kidney were utilized for determination of histopathology, biochemical [aspartate (ALT) and alanine (AST) aminotransferases, alkaline phosphatase (ALP), total bilirrubin (TB) and gamaglutamyl transferase (GGT)] and toxicological parameters [thiobarbituric reactive species (TBARS) levels, catalase activity, ascorbic acid, nonprotein thiols (NPSH) and aminolevulinate dehydratase (δ‐ALA‐D) activity]. Repeated administration of (PhSe)2 caused a marked potentiation of hepatotoxicity induced by CCl4 exposure, as manifested by an increase in biochemical parameters (AST, ALT, ALP, GGT and BT) and severe alteration in histopathology. This study also demonstrated a potentiation of TBARS levels and a consequent depletion of important antioxidant defenses including catalase and ascorbic acid. Pre‐treatment with a single dose of (PhSe)2 prevented the effect of strychnine, a substrate for CYPs, abolishing lethality in mice. This result indicates that (PhSe)2 prevented animal death, suggesting an activator action of (PhSe)2 in CYPs. This study clearly indicates that (PhSe)2 potentiated acute hepatic damage induced by CCl4. Copyright © 2008 John Wiley & Sons, Ltd.
Radiosynthesis and bioconjugation of [18F]FPy5yne, a prosthetic group for the 18F labeling of bioactive peptides
Authors: Inkster James A. H. , Guérin Brigitte , Ruth Thomas J. , Adam Michael J.
Published: November 2008

A new 18F‐based prosthetic group has been prepared for the labeling of azide‐modified peptides for use in PET imaging. 2‐[18F]fluoro‐3‐(hex‐5‐ynyloxy)pyridine ([18F]FPy5yne, [18F]‐1) was prepared via efficient nucleophilic heteroaromatic substitution of either the corresponding 2‐nitro (2) or 2‐trimethylammonium trifluoromethanesulfonate pyridine (3). Best radiochemical yield of [18F]FPy5yne from 2 was 91% by radioTLC (15 min, 110°C, DMSO). From 3, best radiochemical yield by radioTLC was 93% (15 min, 110°C, MeCN). HPLC‐purified [18F]FPy5yne was ligated to model peptide N3–(CH2)4–CO–YKRI–OH by way of CuI‐mediated Huisgen [3+2] cycloaddition in the presence of copper‐stabilizing ligand tris(benzyltriazolylmethyl)amine (TBTA) and N,N‐diisopropylethylamine (DIEA). Bioconjugate radiochemical yields were obtained in average yields of 89%±8.6% (n=4), as judged by radioHPLC. Best non‐decay‐corrected, collected radiochemical yield of modified peptide from end‐of‐bombardment was 5.8% (18.7% decay‐corrected), with a total preparation time of 160 min from start of synthesis. Copyright © 2008 John Wiley & Sons, Ltd.
Arginine ammonification and L‐glutaminase assays as rapid indices of corn nitrogen availability
Authors: Nourbakhsh Farshid , Alinejadian Afsaneh
Published: November 2008

Increasing use of N fertilizer for crop production necessitates more rapid estimates on N provided by the soil in order to prevent under‐ or overfertilization and their adverse effect on plant nutrition and environmental quality. A study was conducted to investigate the responses of arginine ammonification (AA), L‐glutaminase activity (LG), soil N–mineralization indices, corn (Zea mays L.) crop–yield estimation, and corn N uptake to application of organic amendments. The relationships between corn N uptake and the microbial and enzymatic processes which are basically related to N mineralization in soil were also studied. The soil samples were collected from 0–15 cm depth of a calcareous soil that was annually treated with 0, 25, or 100 Mg ha–1 (dry‐weight basis) of sewage sludge and cow manure for 7 consecutive years. Soil total N (TN), potentially mineralizable N (N0), and initial potential rates of N mineralization (kN0) were significantly greater in sewage sludge–treated than in cow manure–treated soils. However, the amendment type did not influence soil organic C (SOC), AA, LG, and anaerobic index of N mineralization (Nana). The application rates proportionally increased N‐availability indices in soil. Corn N concentration and uptake were correlated with indices of mineralizable N. A multiple stepwise model using AA and Nana as parameters provided the best predictor of corn N concentration (R = 0.86, p < 0.001). Another model using only LG provided the best predictor of corn N uptake (R = 0.78, p < 0.001). This results showed that sewage‐sludge and cow‐manure application is readily reflected in certain soil biological properties and that the biological tests may be useful in predicting N mineralization and availability in soil.
Comparing leading theoretical models of behavioral predictions and post‐behavior evaluations
Authors: Richetin Juliette , Perugini Marco , Adjali Iqbal , Hurling Robert
Published: November 2008

This study aimed at comparing the predictive power of the Theory of Planned Behavior (TPB), the Model of Goal‐Directed Behavior (MGB), and the Extended Model of Goal‐Directed Behavior (EMGB) for observed and self‐reported behaviors concerning consumer nondurables. More specifically, the three models were compared in terms of their predictive power for intention and for behavioral desire (only MGB and EMGB). Additionally, the validity of four different models for predicting post‐behavior evaluations was examined. Results showed that the EMGB is the most powerful in predicting both intention and behavioral desire. Moreover, results revealed that, as expected, all three models showed a better predictive power for SRB than for observed behavior. Finally, results demonstrated that post‐behavior evaluations are both online and memory‐based. ©2008 Wiley Periodicals, Inc.
Nano‐Rheology of Single Unentangled Polymeric Lubricant Films
Authors: Guo Qian , Chung Pil Seung , Jhon Myung S. , Choi Hyoung Jin
Published: November 2008

Rheology and tribology become more and more critical issues in order to satisfy the harsh requirements for ultra‐small head/media spacing HDDs. In this communication, MD simulations with a bead/spring model were employed to examine the nano‐rheological response of nonfunctional and functional PFPEs by analyzing the shear viscosity of nanoscale PFPE films and the relaxation processes as a function of wall interaction/separation and endgroup functionality. Our simulation results indicate that thin PFPE films show more solid‐like behavior, especially under high shear rate. The film deformation and shear viscosity change by tuning the film thickness and the endgroup functionality was discussed in conjunction with the relaxation processes.

magnified image
Explicit coupled thermo‐mechanical finite element model of steel solidification
Authors: Koric Seid , Hibbeler Lance C. , Thomas Brian G.
Published: November 2008

The explicit finite element method is applied in this work to simulate the coupled and highly non‐linear thermo‐mechanical phenomena that occur during steel solidification in continuous casting processes. Variable mass scaling is used to efficiently model these processes in their natural time scale using a Lagrangian formulation. An efficient and robust local–global viscoplastic integration scheme (Int. J. Numer. Meth. Engng 2006; 66:1955–1989) to solve the highly temperature‐ and rate‐dependent elastic–viscoplastic constitutive equations of solidifying steel has been implemented into the commercial software ABAQUS/Explicit (ABAQUS User Manuals v6.7. Simulia Inc., 2007) using a VUMAT subroutine. The model is first verified with a known semi‐analytical solution from Weiner and Boley (J. Mech. Phys. Solids 1963; 11:145–154). It is then applied to simulate temperature and stress development in solidifying shell sections in continuous casting molds using realistic temperature‐dependent properties and including the effects of ferrostatic pressure, narrow face taper, and mechanical contact. Example simulations include a fully coupled thermo‐mechanical analysis of a billet‐casting and thin‐slab casting in a funnel mold. Explicit temperature and stress results are compared with the results of an implicit formulation and computing times are benchmarked for different problem sizes and different numbers of processor cores. The explicit formulation exhibits significant advantages for this class of contact‐solidification problems, especially with large domains on the latest parallel computing platforms. Copyright © 2008 John Wiley & Sons, Ltd.
Antimicrobial activity of aniline‐formaldehyde resin modified by adding piperazine moiety and its metal polychelates
Authors: Parveen Shadma , Ahamad Tansir , Malik Ashraf , Nishat Nahid
Published: November 2008

Aniline‐formaldehyde resin modified by adding piperazine (AFP) was prepared in alkaline medium, and its metal polychelates have also been prepared with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) metal ions. The synthesized compounds were characterized by elemental, spectral (UV–Vis, IR, 1H‐NMR and 13C‐NMR), thermogravimetric analysis (TGA), and magnetic moment measurements. The percentage of metal in all of the polychelates was found to be consistent with 1:1 (metal/resin) stoichiometry. The thermal behaviors of these coordination polymers were studied by TGA in a nitrogen atmosphere up to 750°C. The TGA results revealed that all the metal polychelates had higher thermal‐resistance property compared to the common resin (AFP). The magnetic moment measurements and UV–Vis spectra confirmed the geometry of the central metal ion in all the polychelates. All the synthesized metal polychelates showed excellent antibacterial activities against the selected bacteria. The antibacterial activities were determined using the shaking flask method, where 25 mg/ml concentrations of each compound were tested against 105 CFU/ml bacteria solutions. The number of viable bacteria was calculated by using the spread plate method, where 100 µl of the incubated antibacterial agent in bacteria solutions was spread on agar plates, and the number of bacteria was counted after 24 hr of incubation period at 37°C. Copyright © 2008 John Wiley & Sons, Ltd.
Anthropomorphic measurements and event‐free survival in patients with favorable histology Wilms tumor: A report from the Children's Oncology Group
Authors: Fernandez Conrad V. , Anderson James , Breslow Norman E. , Dome Jeffrey S. , Grundy P.E. , Perlman Elizabeth J. , Green Daniel M. ,   The National Wilms Tumor Study Group/Children's Oncology Group
Published: November 2008

Purpose

We retrospectively examined the effect of body weight and body mass index (BMI) on event‐free survival (EFS) of children with Wilms tumor treated on National Wilms Tumor Study‐5 (NWTS‐5).

Patients and methods

Eligible study participants: stages I–IV favorable histology Wilms tumor with immediate nephrectomy; height and weight recorded at diagnosis, and loss of heterozygosity for chromosomes 1p and 16q assessed.

Results

A total of 1,532 patients were included in the analysis. The median follow‐up was 4.9 years. 493 patients were less than 2 years of age and 1039 were 2 years of age or older. In both age groups there were more patients than expected with a weight or body mass index (BMI) less than the 10‰ or greater than the 90‰. There was no relationship of weight‐for‐age or BMI‐for‐age and EFS in univariate analyses (P = 0.28, log‐rank test for both comparisons). A Cox proportional hazards model, stratified by risk/treatment groups, showed that, among patients less than 2 years of age, low or high weight‐for‐age was not predictive of EFS (P = 0.16). Similarly, a Cox proportional hazards model, stratified by risk/treatment groups, showed that among patients greater than 2 years of age, low or high body mass index for age was not predictive of EFS (P = 0.58).

Conclusions

There was no evidence that anthropomorphic data obtained at diagnosis for patients with favorable histology stages I–IV Wilms tumor was predictive for EFS in the setting of current treatment regimens. There were more patients with lower or higher weight/BMI than expected. Pediatr Blood Cancer 2009;52:254–258. © 2008 Wiley‐Liss, Inc.
Management of brain abscesses in children treated for acute lymphoblastic leukemia
Authors: Lackner Herwig , Sovinz Petra , Benesch Martin , Smolle‐Jüttner Freyja , Mokry Michael , Schwinger Wolfgang , Moser Andrea , Urban Christian
Published: November 2008

Brain abscesses in children with leukemia or other malignancies are rare and potentially fatal. We report on four children who developed brain abscesses during treatment for acute lymphoblastic leukemia (ALL). All patients received multimodal broad‐spectrum antibiotic therapy and liposomal amphotericin‐B in combination with hyperbaric oxygen. First‐line antimicrobial treatment was modified when a causative organism was isolated. All four patients survived, with two patients showing complete resolution of neurological and MRI abnormalities and with two patients still having residual lesions. To date, all patients are in remission with three patients still receiving antileukemic therapy. Brain abscesses can be successfully managed by a multimodality approach even in severely immunocompromised cancer patients. Pediatr Blood Cancer 2009;52:408–411. © 2008 Wiley‐Liss, Inc.
Transient TTP in childhood
Authors: Moskowitz Naomi P. , Fligman Igal , Scimeca Philip , Weinblatt Mark
Published: November 2008

Thrombotic thrombocytopenic purpura (TTP) is a type of microangiopathic hemolytic anemia that is uncommon in childhood. Adults with TTP have a high mortality rate unless they are treated with plasma exchange. There are few reports of children with acquired idiopathic TTP, and most of those children received some form of treatment. We describe a child with acquired idiopathic TTP who had severe thrombocytopenia and anemia that resolved over several months without the use of any medications. This case suggests that some children with acquired idiopathic TTP might be safely observed without ill effects. Pediatr Blood Cancer 2009;52:424–426. © 2008 Wiley‐Liss, Inc.
Variation in receipt of opioids by pediatric oncology patients who died in children's hospitals
Authors: Orsey Andrea D. , Belasco Jean B. , Ellenberg Jonas H. , Schmitz Kathryn H. , Feudtner Chris
Published: November 2008

Background

Opioids are a cornerstone of palliation of pain. We sought to assess variation in opioid prescription during the last week of life among a cohort of pediatric oncology patients who died while hospitalized.

Procedure

We used detailed hospital administrative data from the Pediatric Health Information System (PHIS) regarding 1,466 subjects 0–24 years of age who were treated at 33 hospitals between 2001 and 2005.

Results

Among the 1,466 subjects hospitalized at the time of their death, 56% received opioids every day during the hospitalized portion of their last week of life, while 44% did not. This proportion varied substantially across hospitals (range 0–90.5%). After multivariate adjustment for individual‐level characteristics, the hospital‐level effect on the odds of continuous prescription of opioids during the hospitalized portion of the last 7 days of life continued to vary significantly among hospitals, accounting for 10.5% of the variance in the receipt of daily opioid (P < 0.001).

Conclusion

Opioid prescription during the hospitalized portion of the last week of life varies substantially among hospitals, even after adjustment for clinical characteristics of the patients. The reasons for this significant variation, especially the component explained by hospital‐level and not patient‐level factors, warrant more scrutiny. Pediatr Blood Cancer 2009;52:761–766. © 2008 Wiley‐Liss, Inc.
Gene polymorphisms in childhood ALL
Authors: Karathanasis Nikolaos V. , Choumerianou Despoina M. , Kalmanti Maria
Published: November 2008

Acute lymphoblastic leukemia (ALL) is the most common malignancy diagnosed in children. Inherited predisposition and exposure to exogenous leukemogenic agents have been investigated as potential risk factors. Current therapy results in 5‐year event‐free survival exceeding 80% in children in developed countries. Predisposition to ALL and event‐free outcome seems to be influenced by polymorphisms on genes involved in several metabolic pathways. The purpose of this review is to discuss the findings of different studies upon the role of gene polymorphisms in childhood ALL. Pediatr Blood Cancer 2009;52:318–323. © 2008 Wiley‐Liss, Inc.
Luminescent and Optical Properties of Nanocomposite Thin Films Deposited by Remote Plasma Polymerization of Rhodamine 6G
Authors: Aparicio Francisco J. , Borras Ana , Blaszczyk‐Lezak Iwona , Gröning Pierangelo , Álvarez‐Herrero Alberto , Fernández‐Rodríguez Marianela , González‐Elipe Agustin R. , Barranco Angel
Published: November 2008

Mechanically stable and insoluble fluorescent thin films have been deposited by sublimating Rhodamine 6G laser dye in the downstream region of a low‐power microwave ECR plasma using an experimental set‐up designed to control the interaction of the dye molecule with the glow discharge. The use of reactive organosilane plasmas allows to control the dye distribution inside the matrix, leading to solid nanocomposite thin films containing non‐aggregated dye molecules. The suppression of aggregates is a key issue to avoid fluorescence quenching. The obtained nanocomposite films are interesting because of their strong absorption and high fluorescence emission. In addition, they can be patterned using in situ plasma treatments in order to produce optically functional devices.

magnified image
Another look at the conditions for the extraction of protein knowledge‐based potentials
Authors: Betancourt Marcos R.
Published: November 2008

Protein knowledge‐based potentials are effective free energies obtained from databases of known protein structures. They are used to parameterize coarse‐grained protein models in many folding simulation and structure prediction methods. Two common approaches are used in the derivation of knowledge‐based potentials. One assumes that the energy parameters optimize the native structure stability. The other assumes that interaction events are related to their energies according to the Boltzmann distribution, and that they are distributed independently of other events, that is, the quasi‐chemical approximation. Here, these assumptions are systematically tested by extracting contact energies from artificial databases of lattice proteins with predefined pairwise contact energies. Databases of protein sequences are designed to either satisfy the Boltzmann distribution at high or low temperatures, or to simultaneously optimize the native stability and folding kinetics. It is found that the quasi‐chemical approximation, with the ideal reference state, accurately reproduce the true energies for high temperature Boltzmann distributed sequences (weakly interacting residues), but less accurately at low temperatures, where the sequences correspond to energy minima and the residues are strongly interacting. To overcome this problem, an iterative procedure for Boltzmann distributed sequences is introduced, which accounts for interacting residue correlations and eliminates the need for the quasi‐chemical approximation. In this case, the energies are accurately reproduced at any ensemble temperature. However, when the database of sequences designed for optimal stability and kinetics is used, the energy correlation is less than optimal using either method, exhibiting random and systematic deviations from linearity. Therefore, the assumption that native structures are maximally stable or that sequences are determined according to the Boltzmann distribution seems to be inadequate for obtaining accurate energies. The limited number of sequences in the database and the inhomogeneous concentration of amino acids from one structure to another do not seem to be major obstacles for improving the quality of the extracted pairwise energies, with the exception of repulsive interactions. Proteins 2009. © 2008 Wiley‐Liss, Inc.
Molecular dynamics studies on structure and dynamics of phospholamban monomer and pentamer in membranes
Authors: Kim Taehoon , Lee Jinhyuk , Im Wonpil
Published: November 2008

Phospholamban (PLB) is an integral membrane protein of 52 residues that regulates the activity of the sarcoplasmic reticulum calcium pump in cardiac muscle cells through reversible phosphorylation of Ser16. To explore its possible conformations and dynamics in a monomeric state, we have performed comparative molecular dynamics simulations of unphosphorylated and phosphorylated PLB (pPLB) with various orientations in POPC membranes. The simulations indicate that dynamics of the cytoplasmic domain is highly dependent on its interactions with membranes, that is, large conformational changes in the absence of membrane interactions, but very restricted dynamics in their presence. pPLB shows more structural flexibility in its cytoplasmic domain, which is consistent with experimental observations. We have also performed a simulation of a PLB pentameric structure (the so‐called bellflower model), recently determined in micelles, to investigate its behaviors in a POPC membrane. The cytoplasmic domain in each monomer shows uncorrelated dynamics and undergoes large conformational changes toward the membrane surface during the simulation, which supports the so‐called pinwheel model of the PLB pentamer structure. The hydrophobic nature of the pentameric pore excludes water molecules in the pore region, which illustrates that the pore appears to be an energetic barrier for ion and water translocation. Proteins 2009. © 2008 Wiley‐Liss, Inc.
Subband coding for networked control systems
Authors: Quevedo Daniel E. , Silva Eduardo I. , Goodwin Graham C.
Published: November 2008

We study a source coding method for networked control systems (NCSs) for SISO LTI plant models. To make efficient use of limited communication resources between controller and plant actuator, we develop a non‐uniformly sampled subband coding NCS architecture, which we design to minimize a bound on the tracking error variance caused by quantization effects. Our main contribution, in relation to earlier work on subband coding NCSs, lies in that we allow each subband to be equipped with pre‐ and post‐filters. To characterize optimal filters and to solve the subband bit‐allocation problem, we model quantization effects via signal‐to‐noise ratio constraints and explicitly take into account the closed‐loop nature of signals. Simulation results verify that the resultant designs perform exceptionally well, even in non‐idealized situations. Copyright © 2008 John Wiley & Sons, Ltd.
The impact of collaboration on the outcomes of scientific argumentation
Authors: Sampson Victor , Clark Douglas
Published: November 2008

This study examines three questions about the impact of collaboration during scientific argumentation. First, do groups craft better arguments than individuals? Second, to what degree do individuals adopt and internalize the arguments crafted by their group? Third, do individuals who work in groups learn more from their experiences than individuals who work on their own? To examine these questions, 168 high school chemistry students were randomly assigned, using a matched pair design tocollaborativeorindividualargumentation conditions. Students in both treatment conditions first completed a task that required them to produce an argument articulating and justifying an explanation for a discrepant event. The students then completed mastery and transfer problems on their own. The results of this study indicate that (a) groups of students did not produce better arguments than students who worked alone, (b) a substantial proportion of the students adopted at least some elements of their group's argument, and (c) students from the collaborative condition demonstrated superior performance on the mastery and transfer problems. These observations indicate that collaboration was beneficial for individual learning but not for initial performance on the task. The study concludes with a discussion of these observations and recommendations for future research. © 2008 Wiley Periodicals, Inc.Sci Ed93:448–484, 2009
Sustainable tourism development: how do destination stakeholders perceive sustainable urban tourism?
Authors: Timur Seldjan , Getz Donald
Published: November 2008

This paper examines the concept of sustainable tourism development in urban destinations. Both qualitative and quantitative data are employed, from interviews and questionnaires undertaken in Victoria and Calgary, Canada, and San Francisco, USA. Respondents representing the three clusters of the tourism industry, local government and the host environment were examined on their interpretation of ‘sustainable tourism’, sustainability goals and barriers to achieving sustainable tourism in urban destinations. Results revealed important similarities and differences among key stakeholders, and particularly a lack of appreciation for a triple bottom line approach among the tourism industry respondents. Implications are discussed for building a more participative policy approach to sustainable urban tourism development. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.
Polarization Dependence of the C 1s X‐ray Absorption Spectra of Individual Multi‐Walled Carbon Nanotubes
Authors: Najafi Ebrahim , Cruz Daniel Hernández , Obst Martin , Hitchcock Adam P. , Douhard Bastien , Pireaux Jean‐Jacques , Felten Alexandre
Published: November 2008

The polarization dependence (linear dichroism) of the C 1s X‐ray absorption spectrum of individual multi‐walled carbon nanotubes (MWCNTs) is measured using scanning transmission X‐ray microscopy. A very strong dichroic effect is found in the C 1s → π* transition, with almost complete disappearance of this transition when the electric‐field (E)‐vector is aligned parallel to high‐quality (low‐defect) MWCNTs and maximum intensity when the E‐vector is orthogonal to the tube axis. In contrast, there is very little dichroism in the C 1s → σ* transitions. The origin of this polarization effect is explained. The magnitude of the polarization dependence is found to differ in MWCNTs synthesized by different methods (arc discharge versus chemical vapor deposition). This is ascribed to differences in densities of sp2‐type defects. The potential for use of this signal to characterize defects in single‐carbon‐nanotube devices is discussed.
Maple syrup urine disease (MSUD)—Clinical profile of 47 Filipino patients
Authors: Lee J. Y. , Chiong M. A. , Estrada S. C. , Cutiongco‐De la Paz E. M. , Silao C. L. T. , Padilla C. D.
Published: November 2008

Maple syrup urine disease (MSUD) is a very rare disorder of branched‐chain amino acid metabolism. However, it is the most common inborn error of metabolism in the Philippines. We present a retrospective review of 21 patients diagnosed with MSUD between 1999 and 2004. The patients presented clinically between 2 and 14 days of life (mean 5 days) and the diagnosis of MSUD was established between 6 days and 11 months of age (mean 39 days). The classical burnt sugar odour was noted in the majority of patients (81%). The diagnosis of MSUD was initially based on clinical suspicion and confirmed biochemically by measurement of leucine/isoleucine levels by thin‐layer chromatography. The acute management included removal of accumulated branched‐chain amino acids by peritoneal dialysis in 62% of the patients. Mortality rate of this group of patients was 24% and follow‐up rate was 87%. We compared this series with a previously reported series of 26 patients to determine whether diagnosis and the management of MSUD improved over the two periods. Four cases have been diagnosed early since 1992, the majority of whom had the classic form of MSUD with the onset of symptoms in the first two weeks of life. A small subset of patients with early nonspecific symptoms was diagnosed much later owing to a low‐level clinical suspicion among clinicians. Overall, however, there appears to be a small but general trend towards earlier diagnosis, reduced mortality and long‐term follow up in the later series. Although we are able to diagnose and manage MSUD in the Philippines, we recognize that the clinical outcome remains poor and is due mainly to late referral of cases and inadequate long‐term management. In the Philippines, we recommend that all newborns who are considered to be septic, have feeding difficulties, fail to regain their birth weight or present with any other symptoms suggestive of MSUD be evaluated in the first instance by analysis of urine for ketones and if they are positive have blood collected and sent to our laboratory for leucine/isoleucine measurement.
Dietary Marine‐Derived Tocopherol has a Higher Biological Availability in Mice Relative to Alpha‐Tocopherol
Authors: Gotoh Naohiro , Watanabe Hiroyuki , Oka Tomiko , Mashimo Daisuke , Noguchi Noriko , Hata Kazuhiko , Wada Shun
Published: November 2008

The biologic availability of two kinds of tocomonoenols, marine‐derived tocopherol (MDT) and α‐tocomonoenol, was investigated in ICR mice. Vitamin E‐deficient ICR mice were fed MDT and α‐tocomonoenol together with α‐tocopherol, β‐tocopherol, γ‐tocopherol, and δ‐tocopherol, and storage in liver, spleen, lung, and brain was quantified using reverse‐phase high‐performance liquid chromatography. The vitamin E relative biologic availability (VE‐RBA) in liver was 100 for α‐tocopherol, 26 ± 3 for β‐tocopherol, 4 ± 2 for γ‐tocopherol, not detected for δ‐tocopherol, 49 ± 6 for MDT, and 30 ± 7 for α‐tocomonoenol. The VE‐RBA in brain was 100 for α‐tocopherol, 5 ± 2 for β‐tocopherol, not detected for γ‐tocopherol and δ‐tocopherol, 8 ± 1 for MDT, and 4 ± 1 for α‐tocomonoenol. Tocopherols and tocomonoenols did not accumulate in the spleen or lung. MDT and α‐tocomonoenol had high VE‐RBA values. The VE‐RBA value for MDT was much higher than that for β‐tocopherol.
The essential divine-perfection objection to the free-will defence
Authors: PRUSS ALEXANDER R.
Published: November 2008

The free-will defence (FWD) holds that the value of significant free will is so great that God is justified in creating significantly free creatures even if there is a risk or certainty that these creatures will sin. A difficulty for the FWD, developed carefully by Quentin Smith, is that God is unable to do evil, and yet surely lacks no genuinely valuable kind of freedom. Smith argues that the kind of freedom that God has can be had by creatures, without a risk of creatures doing evil. I shall show that Smith's argument fails – the case of God is disanalogous to the case of creatures precisely because creatures are creatures.
Does Molinism explain the demographics of theism?
Authors: MAITZEN STEPHEN
Published: November 2008

I reply to Jason Marsh's discussion of my article ‘Divine hiddenness and the demographics of theism’. For several reasons, Marsh's inventive Molinist explanation of the lopsided worldwide distribution of theistic believers does not threaten the conclusion I argued for originally: theistic explanations of that distribution are implausible on even their own terms and in any case less plausible than naturalistic ones.
HITIQA: High-quality intelligence through interactive question answering
Authors: SMALL S. , STRZALKOWSKI T.
Published: November 2008

We describe an interactive question answering system, HITIQA, which helps users find answers to complex analytical problems. Such problems often necessitate the user to submit not one but an entire series of questions, both simple and complex, and then to negotiate the final content and form of the answer. HITIQA advances research in human–computer dialogue by enabling topical, mixed initiative interaction over unstructured data. HITIQA uses the process of text framing to bring a level of semantic representation to open-domain data in order to facilitate meaningful dialogue with the user. In this paper we give an overview of HITIQA's design and explain the workings of its main components with particular attention given to its dialogue capabilities. We also present results of end-to-end system evaluations that demonstrate the effectiveness of the system as a whole, as well as contributions of the individual components and specifically the benefits of our dialogue-based approach. While our research continues, a number of HITIQA prototypes have recently been deployed at various government agencies where they are being tested under real operational conditions.
Allium vegetables intake and endometrial cancer risk
Authors: Galeone Carlotta , Pelucchi Claudio , Dal Maso Luigino , Negri Eva , Montella Maurizio , Zucchetto Antonella , Talamini Renato , La Vecchia Carlo
Published: November 2008

Objective

The potential role of allium vegetables on endometrial cancer risk has been scarcely investigated and the results of previous Chinese studies are not easily applicable to Western populations. Therefore, we evaluated the relationship between onion and garlic intake and endometrial cancer, using data from an Italian case–control study.

Setting

We analysed data from a multi-centre case–control study of 454 endometrial cancer cases and 908 controls, admitted to the same hospitals for a wide spectrum of acute, non-neoplastic conditions. Information was collected by trained interviewers using a validated and reproducible FFQ. Multivariate odds ratios and 95 % confidence intervals were obtained after allowance for recognized confounding factors.

Results

Compared with non-users, the OR of endometrial cancer for successive categories of onion intake were 0·94 (95 % CI 0·72, 1·21) for <2 portions/week and 0·40 (95 % CI 0·22, 0·72) for ≥2 portions/week, with a significant inverse trend in risk (P = 0·01). The OR for an increment of one portion (i.e. 80 g) of onions per week was 0·81 (95 % CI 0·70, 0·95). For garlic, the OR for successive categories of intake were 0·89 (95 % CI 0·68, 1·15) for intermediate use and 0·62 (95 % CI 0·42, 0·92) for high use, with a significant inverse trend in risk (P = 0·02).

Conclusions

Our study found a moderate protective role of allium vegetables on the risk of endometrial cancer.
A comparison of the fat composition and prices of margarines between 2002 and 2006, when new Canadian labelling regulations came into effect
Authors: Ricciuto Laurie , Lin Kevin , Tarasuk Valerie
Published: November 2008

Objective

To examine the effect of the new Canadian labelling regulations on the fat composition and prices of margarines.

Study design

A survey of all margarines sold in major supermarkets in the Greater Toronto area was conducted in 2006, and results were compared with those of a similar survey conducted in 2002. Average fat composition, proportion of ‘trans fat-free’ margarines and average prices of margarines were compared. A general linear model procedure was used to compare the relationship between price and fat composition in 2002 and 2006.

Results

Average amounts of trans fatty acids (TFA) and MUFA decreased, while average amounts of PUFA increased significantly from 2002 to 2006. The proportion of margarines with less than 0·2 g TFA/10 g serving rose significantly from 31 % in 2002 to 69 % in 2006. Margarines lower in TFA on average cost significantly more than margarines with greater amounts of these fats, and this relationship appeared stronger in 2006 relative to 2002.

Conclusions

There is evidence of reductions in TFA in margarines since new labelling regulations came into effect in Canada; however, TFA reductions appeared to be restricted to higher-priced margarines. Results suggest that voluntary approaches (i.e. manufacturer incentives via labelling) to reduce population intakes of TFA will yield little changes in TFA content of low-cost products and thus may have limited benefit for lower-income groups, who are at higher risk of heart disease.
Two-Photon Imaging of Cellular Activities in Oxygen Sensing Tissues
Authors: Wotzlaw Christoph , Berchner-Pfannschmidt Utta , Fandrey Joachim , Acker Helmut
Published: November 2008

The cellular oxygen sensing system of the body ensures appropriate adaptation of cellular functions toward hypoxia by regulating gene expression and ion channel activity. Two-photon laser microscopy is an ideal tool to study and prove the relevance of the molecular mechanisms within oxygen sensing pathways on the cellular and complex tissue or organ level. Images of hypoxia inducible factor 1 (HIF-1) subunit nuclear mobility and protein-protein interaction in living cells, of hypoxia-induced changes in membrane potential and intracellular calcium of live ex vivo carotid bodies as well as of rat kidney proximal tubulus function in vivo, will be shown.
On the Field Evaporation Behavior of a Model Ni-Al-Cr Superalloy Studied by Picosecond Pulsed-Laser Atom-Probe Tomography
Authors: Zhou Yang , Booth-Morrison Christopher , Seidman David N.
Published: November 2008

The effects of varying the pulse energy of a picosecond laser used in the pulsed-laser atom-probe (PLAP) tomography of an as-quenched Ni-6.5 Al-9.5 Cr at.% alloy are assessed based on the quality of the mass spectra and the compositional accuracy of the technique. Compared to pulsed-voltage atom-probe tomography, PLAP tomography improves mass resolving power, decreases noise levels, and improves compositional accuracy. Experimental evidence suggests that Ni2+, Al2+, and Cr2+ions are formed primarily by a thermally activated evaporation process, and not by post-ionization of the ions in the 1+charge state. An analysis of the detected noise levels reveals that for properly chosen instrument parameters, there is no significant steady-state heating of the Ni-6.5 Al-9.5 Cr at.% tips during PLAP tomography.