bluuebunny/crossref_metadata_2025 huggingface dataset:
The Influence of the thermal insulation of the window frameworks on the energy performance of the window
Authors: Moga Ioan , Moga Ligia
Published: December 2008

The paper presents the energetic performances of a window in diverse constructive realization solutions and the thermal protection of its frame. The study made has at its basis the numeric analysis of the temperature field upon the effect made by the joining of the thermal insulation from the walls on the embrasures of the window hole. The heat transfer through the window‐wall‐insulation ensemble was determined with the help of the “WINDOW‐WALL” calculus program derived from the calculus program CIMPSPAT, made by the authors in the variant 2008 (first variant in 1980) written in the programming language Delphi under Windows environment. The analysis of the interior microclimate conditions existing in the dwelling houses from our country, leads to the necessity of a better knowing of the heat transfer phenomena closer to the real phenomenon that takes place in the case of the windows placed in different situations of exploitation. The practical finding of different behavior of windows, the condense phenomenon met on the interior surface of the window framework and the contour in which the window is placed, calls for the necessity of the calculus presented in the paper.
Wärme‐ und Feuchtetransport in Vakuumisolationspaneelen
Authors: Beck Andreas , Binder Markus
Published: December 2008

Wegen ihrer extrem niedrigen Wärmeleitfähigkeit und der damit verbundenen Möglichkeiten, mit geringen Bauteildicken hochwertig zu dämmen, haben Vakuumisolationspaneele (VIP) innerhalb kurzer Zeit Verbreitung im Bauwesen gefunden – insbesondere in Situationen, in denen andere Dämmstoffe aus Platzgründen nicht in Frage kommen. Da noch keine Langzeiterfahrungen über die Alterung der Paneele vorhanden sind, muss beim Bemessungswert der Wärmeleitfähigkeit im Moment allerdings noch mit hohen Sicherheitszuschlägen gerechnet werden, vor allem wegen des über die Nutzungsdauer stattfindenden Gaseintrags. Besonders von Interesse ist hierbei das Verhalten von aus der Umgebung eindiffundierendem Wasserdampf. Während die Auswirkungen von trockenen Gasen genau bezifferbar sind, überlagern sich beim Stoff‐ und Wärmetransport durch Wasser verschiedene Vorgänge, die die Wärmeleitung im VIP deutlich erhöhen, aber messtechnisch nur schwer erfassbar sind. Daher wurde ein theoretisches Modell entwickelt, das den Wärmestrom auf Grundlage der kinetischen Gastheorie für Molekularströmung und Oberflächendiffusion beschreibt und darüber hinaus Rückschlüsse auf die Diffusionseigenschaften des Kernmaterials zulässt.
Assessment of the efficacy and safety of low frequency, low intensity magnetic fields in patients after knee endoprosthesis plasty. Part 2: A Clinical Study
Authors: Błaszczak Edward , Franek Andrzej , Taradaj Jakub , Widuchowski Jerzy , Klimczak Jerzy
Published: December 2008

The purpose of this clinical study was to assess low frequency, low intensity magnetic fields in the enhancement of the physical rehabilitation of patients after knee endoprosthesis surgery. The study included 62 patients who underwent total knee arthroplasty. Group A consisted of 32 patients who were physically rehabilitated. Group B consisted of 30 patients who were physically rehabilitated and treated additionally with pulsing magnetic fields (5 mT, 30 Hz, 20 min once a day, 5 days weekly). Therapy lasted 3 weeks for both groups. The rehabilitation process was evaluated using a goniometer, tensometer, goniometric pendulum test, Lysholm scale for knee function, and a visual analogue scale (VAS) questionnaire for pain and activity. The changes of measured rates were comparable in both groups. Low frequency and low intensity magnetic fields of examined parameters were not demonstrated to effectively improve the rehabilitation of patients after knee endoprosthesis surgery. Bioelectromagnetics 30:152–158, 2009. © 2008 Wiley‐Liss, Inc.
Application of Molecular Connectivity and Electro‐Topological Indices in Quantitative Structure–Activity Analysis of Pyrazole Derivatives as Inhibitors of Factor Xa and Thrombin
Authors: Krishnasamy Chandravel , Raghuraman Arjun , Kier Lemont B. , Desai Umesh R.
Published: December 2008

Factor Xa and thrombin, two critical pro‐coagulant enzymes of the clotting cascade, are the primary target of current anticoagulation research that aims to develop potent, orally bioavailable, synthetic small‐molecule inhibitors. To determine structural features that might play important roles in factor Xa and thrombin recognition and oral bioavailability, quantitative structure–activity and structure–property analyses were performed on the factor Xa and thrombin inhibition data and Caco‐2 cell‐permeability data of 3‐substituted pyrazole‐5‐carboxamides reported by Pinto et al. (J. Med. Chem. 2001, 44, 566). The factor Xa and thrombin inhibition potencies, and Caco‐2 cell permeability of the 3‐substituted pyrazole‐5‐carboxamides could be quantitatively described through molecular connectivity and atom level E‐state indices. Different quantitative structure–activity and structure–property models were derived for each of the three biological properties. The models are statistically relevant with correlation coefficients of at least 0.9, and contain only two or three molecular descriptor variables. The study demonstrates the use of molecular connectivity and E‐state indices in understanding factor Xa and thrombin inhibition. In addition, the models may be useful for predictive purposes in generating molecules with better potency, specificity, and oral bioavailability.
Controlled Release of Volatile Secondary and Tertiary Alcohols by Neighboring Group Participation: Stepwise Cyclization and Re‐Opening of 2,2′‐Bis(carbamoyl)dibenzoates at Neutral pH
Authors: Trachsel Alain , Govoni Alexandra , de Saint Laumer Jean‐Yves , Frérot Eric , Herrmann Andreas
Published: December 2008

Bioactive, volatile, secondary and tertiary fragrance alcohols are efficiently released by intramolecular neighboring‐group‐assisted hydrolysis of 2,2′‐bis(carbamoyl)dibenzoates at neutral pH. The stepwise cyclization of 2,2′‐[(methylimino)bis(propane‐3,1‐diylcarbamoyl)]dibenzoates is followed by the re‐opening of the intermediately formed diphthalimide and proceeds in an overall four‐step consecutive reaction sequence. Kinetic rate constants for all four reaction steps could be determined pairwise by reversed‐phase HPLC. At neutral pH, secondary alcohols were released by one order of magnitude faster than the tertiary alcohols, and the rate constants for the re‐opening of the diphthalimides were found to be in the same order of magnitude as the release of the tertiary alcohols. Dynamic headspace analysis on a dry cotton surface finally confirmed the efficient release of tertiary alcohols under mild reaction conditions generally encountered for applications in functional perfumery.
Immunosuppressive Activity of the Ethanol Extract of Sedum sarmentosum and Its Fractions on Specific Antibody and Cellular Responses to Ovalbumin in Mice
Authors: Qin Feng , Sun Hong‐Xiang
Published: December 2008

The immunosuppressive activity of the ethanol extract of Sedum sarmentosum (EESS) and its fractions was studied with respect to specific antibody and cellular response to ovalbumin (OVA) in mice. ICR Mice were immunized subcutaneously with OVA on days 0 and 14. Beginning on the day of immunization, the mice were administered intraperitoneally (ip) with EESS and it fractions at a single dose of 0.25, 0.5, and 1.0 mg, and cyclosporin A at a single dose of 0.1 mg at intervals of 7 days. On day 28, splenocyte proliferation and specific antibody level in serum were measured. EESS significantly suppressed concanavalin A (Con A)‐, lipopolysaccharide (LPS)‐, and OVA‐induced splenocyte proliferation in the immunized mice in a dose‐dependent manner. The OVA‐specific serum IgG, IgG1, and IgG2b levels in the immunized mice were also markedly reduced by EESS. Among four fractions of EESS, the BuOH fraction consisting mainly of flavonoid glycosides showed the highest suppressive activity. The results suggest that EESS could suppress the cellular and humoral immune response in mice, and deserve further research to be developed as immunosuppressant.
Larvicidal and Nematicidal Activities of the Leaf Essential Oil of Croton regelianus
Authors: Torres Maria Conceição M. , Assunção João Carlos , Santiago Gilvandete Maria P. , Andrade‐Neto Manoel , Silveira Edilberto R. , Costa‐Lotufo Leticia V. , Bezerra Daniel P. , Filho José Delano B. Marinho , Viana Francisco Arnaldo , Pessoa Otília Deusdênia L.
Published: December 2008

The chemical composition of the leaf essential oil of Croton regelianus collected from wild plants growing in two different sites at Ceará State (Brazil) was analyzed by GC/MS and GC‐FID. Twenty monoterpenoids, representing more than 96% of the chemical composition of the oils, were identified and quantified. The oils showed similar chemical composition but considerable variation in the levels of each constituent. Ascaridole (33.9–17.0%), p‐cymene (22.3–21.6%), and camphor (13.0–3.1%) were the predominant constituents. The monoterpene ascaridole was isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti and Artemia sp. larvae, and the root knot nematode Meloidogyne incognita. The bioassay results show that the essential oil of C. regelianus and ascaridole were moderately active against the M. incognita, but strongly effective against both A. aegypti and Artemia sp. larvae.
Synthesis of Polycyclic Aromatic Hydrocarbons and Acetylene Polymers in Ice: A Prebiotic Scenario
Authors: Menor‐Salván César , Ruiz‐Bermejo Marta , Osuna‐Esteban Susana , Muñoz‐Caro Guillermo , Veintemillas‐Verdaguer Sabino
Published: December 2008

The recent evidences of presence of subsurface oceans of liquid water and ice on Saturn's moons, and the possible presence and astrobiological importance of polycyclic aromatic hydrocarbons (PAHs) in these environments, provide strong motivation for the exploration of the prebiotic chemistry in ice and to test if PAHs could be experimentally synthesized in ice surfaces under atmospheres containing methane as carbon source. In this work, we present a new design for prebiotic‐chemistry experiments in ice matrix. Using this design, a mixture of products including PAHs, polar aromatic compounds, and hydrophilic acetylene‐based polymers was obtained. We propose that acetylene generation in a methane/nitrogen atmosphere and subsequent polymerization to PAHs and polyynes could be a favored pathway in the presence of water freeze–melt cycles. These results shed light on the processes involved in PAH synthesis in icy environments and on the physical factors that drive the different competing pathways in methane/nitrogen atmospheres.
The Metallothionein/Thionein System: An Oxidoreductive Metabolic Zinc Link
Authors: Bell Stephen G. , Vallee Bert L.
Published: December 2008

Metallothioneins (MTs) were discovered more than 50 years ago and identified as low‐molecular weight, sulfhydryl‐rich proteins that were subsequently found to bind zinc predominantly. The binding of seemingly redox inactive zinc ions allows MT to play a central role in oxidoreductive cellular metabolism, cellular zinc distribution and homeostasis. In this interpretive study, we discuss the interaction of MT with physiologically relevant molecules and its effect on zincthiolate bonds. These interactions are linked to recent progress in the functional role of MT in cellular zinc transport, energy production, and protection of the organism against oxidative stress and neurodegenerative diseases.
Biological Implications of the Ribosome's Stunning Stereochemistry
Authors: Zimmerman Ella , Yonath Ada
Published: December 2008

The ribosome's striking architecture is ingeniously designed for its efficient polymerase activity in the biosynthesis of proteins, which is a prerequisite for cell vitality. This elaborate architecture is comprised of a universal symmetrical region that connects all of the ribosomal functional centers involved in protein biosynthesis. Assisted by the mobility of selected ribosomal nucleotides, the symmetrical region provides the structural tools that are required not only for peptide bond formation, but also for fast and smooth successive elongation of nascent proteins. It confines the path along which the A‐tRNA 3′‐end is rotated into the P‐site in concert with the overall tRNA/mRNA sideways movement, thus providing the required stereochemistry for peptide bond formation and substrate‐mediated catalysis. The extreme flexibility of the nucleotides that facilitate peptide bond formation is being exploited to promote antibiotic selectivity and synergism, as well as to combat antibiotic resistance.
Mathematics anxiety in secondary students in England
Authors: Chinn Steve
Published: December 2008

Whatever the changes that are made to the mathematics curriculum in England, there will always remain a problem with mathematics anxiety. Maths anxiety is rarely facilitative. This study examined aspects of mathematics in secondary schools and how students rated them as sources of anxiety. Over 2000 students in independent and mainstream schools in England completed a 20‐item questionnaire designed to investigate maths anxiety levels. The same questionnaire was given to over 440 dyslexic males in specialist schools within the same age range. The results showed that examinations and tests create high levels of anxiety in approximately 4% of students. The results suggest that certain aspects and topics in the maths curriculum, such as long division, cause similar levels of anxiety for students in all year groups in secondary schools. Copyright © 2008 John Wiley & Sons, Ltd.
Screening for dyslexia, dyspraxia and Meares‐Irlen syndrome in higher education
Authors: Nichols S. A. , McLeod J. S. , Holder R. L. , McLeod H. S. T.
Published: December 2008

This study reports a comparison of screening tests for dyslexia, dyspraxia and Meares‐Irlen (M‐I) syndrome in a Higher Education setting, the University of Worcester. Using a sample of 74 volunteer students, we compared the current tutor‐delivered battery of 15 subtests with a computerized test, the Lucid Adult Dyslexia Screening test (LADS), and both of these with data on assessment outcomes. The sensitivity of this tutor battery was higher than LADS in predicting dyslexia, dyspraxia or M‐I syndrome (91% compared with 66%) and its specificity was lower (79% compared with 90%). Stepwise logistic regression on these tests was used to identify a better performing subset of tests, when combined with a change in practice for M‐I syndrome screening. This syndrome itself proved to be a powerful discriminator for dyslexia and/or dyspraxia, and we therefore recommend it as the first stage in a two‐stage screening process. The specificity and sensitivity of the new battery, the second part of which comprises LADS plus four of the original tutor delivered subtests, provided the best overall performance: 94% sensitivity and 92% specificity. We anticipate that the new two‐part screening process would not take longer to complete. Copyright © 2008 John Wiley & Sons, Ltd.
Calculating investment incentives in the European electricity market
Authors: Paulun Tobias
Published: December 2008

The situation for utilities in the European electricity market has changed significantly over the last years due to liberalization of the market. It is the aim of current Energy politics of the European Commission to establish a truly competitive internal market for electricity throughout the whole European Union. For this, new market rules are defined and boundary conditions for investments in electricity generating and transmission capacities are changed. In order to evaluate the impact of boundary conditions on the development of the market, market models are becoming more and more important. However, most of the existing models neglect technical restrictions of electricity generation and transmission or coherences between those areas that may affect the development of the market in reality. In this contribution, a general framework of a newly developed market model is presented. This model incorporates technical restrictions of electricity generation and transmission and provides a basis for simulating the future development of the electricity market. This article presents first results regarding incentives of electricity generating companies for investments in additional generation capacities. Copyright © 2008 John Wiley & Sons, Ltd.
A lattice Boltzmann method for solute transport
Authors: Zhou Jian Guo
Published: December 2008

A lattice Boltzmann method is developed for solute transport. Proper expressions for the local equilibrium distribution functions enable the method to be formulated on rectangular lattice with the same simple procedure as that on a square lattice. This provides an additional advantage over a lattice Boltzmann method on a square lattice for problems characterized by dominant phenomenon in one direction and relatively weak in another such as solute transport in shear flow over a narrow channel, where the problems can efficiently be approached with fine and coarse meshes, respectively, resulting in more efficient algorithm. The stability conditions are also described. The proposed method on a square lattice is naturally recovered when a square lattice is used. It is verified by solving four tests and compared with the analytical/exact solutions. They are in good agreement, demonstrating that the method is simple, accurate and robust for solute transport. Copyright © 2008 John Wiley & Sons, Ltd.
Evaluation of a home‐based exercise program in the treatment of Alzheimer's disease: The Maximizing Independence in Dementia (MIND) study
Authors: Steinberg Martin , Leoutsakos Jeannie‐Marie Sheppard , Podewils Laura Jean , Lyketsos C. G.
Published: December 2008

Objective

To determine the feasibility and efficacy of a home‐based exercise intervention program to improve the functional performance of patients with Alzheimer's Disease (AD).

Methods

Twenty‐seven home‐dwelling patients with AD were randomized to either an exercise intervention program delivered by their caregivers or a home safety assessment control. Measures of functional performance (primary), cognition, neuropsychiatric symptoms, quality of life and caregiver burden (secondary) were obtained at baseline and at 6 and 12 weeks following randomization. For each outcome measure, intent‐to‐treat analyses using linear random effects models were performed. Feasibility and adverse events were also assessed.

Results

Adherence to the exercise program was good. On the primary outcomes (functional performance) patients in the exercise group demonstrated a trend for improved performance on measures of hand function and lower extremity strength. On secondary outcome measures, trends toward worse depression and lower quality of life ratings were noted.

Conclusions

The physical exercise intervention developed for the study, delivered by caregivers to home‐dwelling patients with AD, was feasible and was associated with a trend for improved functional performance in this group of frail patients. Given the limited efficacy to date of pharmacotherapies for AD, further study of exercise intervention, in a variety of care setting, is warranted. Copyright © 2008 John Wiley & Sons, Ltd.
A Concise Total Synthesis of Diospongins A and B
Authors: Sabitha Gowravaram , Padmaja Pannala , Yadav Jhillu S.
Published: December 2008

The total synthesis of the diarylheptanoids (−)‐diospongin A (1) and B (2) was achieved stereoselectively via the δ‐lactone intermediate 6. The key reactions involved are a stereoselective reduction of β‐keto ester and the Horner–Wadsworth–Emmons and intramolecular oxy‐Michael reactions.
A New Insight into the Catalytic Decomposition of Ethyl Diazoacetate in the Presence of meso‐Tetraarylporphyrin (=5,10,15,20‐Tetraaryl‐21H,23H‐porphine) Complexes
Authors: Gomes Ana T. P. C. , Leão Raquel A. C. , Alonso Cristina M. A. , Neves Maria G. P. M. S. , Faustino Maria A. F. , Tomé Augusto C. , Silva Artur M. S. , Pinheiro Sergio , de Souza Maria Cecília B. V. , Ferreira Vítor F. , Cavaleiro José A. S.
Published: December 2008

The decomposition of ethyl diazoacetate by several catalysts in the presence of meso‐tetraarylporphyrin complexes with different electronic features was evaluated. The distribution of the obtained products (chlorins, bacteriochlorins, isobacteriochlorins, and porphyrin derivatives resulting from CH insertion and Büchner ring expansion) is dependent on the catalyst and on the electronic features of the meso‐aryl groups.
Amphiphilic Multi‐Arm Block Copolymer Based on Hyperbranched Polyester, Poly(L‐lactide) and Poly(ethylene glycol) as a Drug Delivery Carrier
Authors: Prabaharan Mani , Grailer Jamison J. , Pilla Srikanth , Steeber Douglas A. , Gong Shaoqin
Published: December 2008

A novel type of biodegradable/biocompatible amphiphilic hyperbranched copolymer (H40‐PLA‐b‐MPEG) was synthesized. Its micellar properties were studied by DLS, fluorescence spectroscopy and TEM. The drug release profile showed that the H40‐PLA‐b‐MPEG micelles provide an initial burst release, followed by a sustained release of the entrapped hydrophobic model drug over a period of 4 to 58 h. The copolymer degraded hydrolytically within 6 weeks under physiological conditions. The MTT assay showed no obvious cytotoxicity against a human endothelial cell line at a concentration range of 0–400 µg · mL−1. These results indicate that the H40‐PLA‐b‐MPEG micelles have great potential as hydrophobic drug delivery carriers.

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Structure of corrosion film formed on copper exposed to controlled corrosive environment
Authors: Reid M. , Tanner D. A. , Belochapkine S. , Garfias L. F.
Published: December 2008

This paper describes a transmission electron microscopy (TEM) investigation of copper coupons exposed to a corrosive mixed flowing gas environment (MFG). A focused ion beam (FIB) lift‐out technique was used to extract electron transparent specimens for TEM investigation. A duplex corrosion film comprising cuprite (Cu2O) and chalcocite (Cu2S) developed on the copper substrate. The oxide demonstrated a dense morphology with evidence of chlorine in the oxide layer showing that chlorine plays an important role in the corrosion of copper transforming the protective Cu2O layer to a non‐protective layer. The outer layer of the Cu2S demonstrated a porous morphology allowing easy penetration of water and gases.
Synthesis and Photoresponsive Properties of Optically Active Methacrylic Polymers Bearing Side‐Chain Azocarbazole Moieties
Authors: Angiolini Luigi , Giorgini Loris , Mauriello Francesco , Rochon Paul
Published: December 2008

The synthesis of a novel optically active methacrylic monomer containing in the side chain the (S)‐3‐hydroxy‐N‐phenyl pyrrolidine ring linked to a 4‐cyanophenylazocarbazole moiety [(S)‐MCAPP‐C] and of the analogous achiral monomer (MCAPE‐C) is described. Both the monomers have been radically polymerized to produce the corresponding homopolymers as well as the copolymer at 50% molar composition. The photoinduction of birefringence has been assessed on thin films of the polymeric materials in order to evaluate their behavior as materials for optical data storage. Surface relief gratings (SRG) can also be inscribed over the material. The results are interpreted in terms of different cooperative performance and conformational stiffness of the chromophoric co‐units in the polymeric derivatives.

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Synthesis of Amphiphilic Supramolecular Miktoarm Star Copolymers by Molecular Recognition
Authors: Lu Dairen , Wang Yun , Tao Kang , Bai Ruke
Published: December 2008

Synthesis of novel amphiphilic supramolecular miktoarm star copolymers has been achieved through complementary molecular recognition and interactions between carboxy groups and amino groups. Polystyrenes carrying two and one carboxy groups at the middle of the polymer chain are used as precursors to react with poly(ethylene oxide) (PEO) end‐capped with a primary amine functionality (–NH2) or a quaternary ammonium hydroxide functionality (–N+(CH2CH3)3OH−). The result suggests that the basicity of the amine plays a key role in the molecular recognition procedure. The efficiency of ionic bond formation can be enhanced from 40% up to 97% by using PEO‐N+(CH2CH3)3OH− instead of PEO‐NH2. The obtained supramolecular polymers can be dissociated in dilute acid solution at room temperature.

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Macromol. Rapid Commun. 24/2008
Authors: Takeuchi Daisuke , Matsuura Ryuichi , Osakada Kohtaro
Published: December 2008

Cover: Co‐bisimino(pyridine) complex catalyzes not only the cyclopolymerization of 1,6‐heptadiene, but also the random copolymerization of the diene with ethylene. The resulting polymer contains transfused five‐membered rings along the linear polymer chain. The copolymers with a density variety of cyclic units exhibit different thermal properties depending on the polymerization conditions. Further details can be found in the article by D. Takeuchi, R. Matsuura, and K. Osakada* on page 1932.
Application of Fluorescence Depolarization Method to Monitor Free Volume in Gels of Stereoregular Polystyrene
Authors: Itagaki Hideyuki
Published: December 2008

Summary: A fluorescence depolarization technique was applied to get the information on free volume among polymer chains in gel form. Four fluorescent molecules with different molecular sizes were doped throughout the gels of syndiotactic polystyrene (sPS) and isotactic polystyrene (iPS) physical gel system, and their fluorescence anisotropy values were examined in detail for a range of polymer concentrations. Consequently, the free volume among sPS chains in sPS/chloroform gels is as large as the size of molecules smaller than 1,5‐dimethylnaphthalene and is consistent with that of the cavity size in the δ‐empty crystalline form of sPS solids. The cause to produce δ‐empty crystalline form of sPS solids and to form cocrystals between sPS and guest molecules is discussed by comparing the molar size of guest molecules with the free volume among sPS chains in gel form.
Thermoreversible Poly(vinylidene fluoride) Gels: A Precursor to Multiporous Polymeric Materials
Authors: Dasgupta D. , Guenet J. M. , Nandi A. K.
Published: December 2008

Summary: The thermodynamics of gelation of poly(vinylidene fluoride)(PVF2) with camphor (CP) and ethylene carbonate (EC) suggest polymer‐solvent compound formation. The presence of solvent molecules in the polymer crystalline phase of the gel is accordingly shown by wide angle X‐ray diffraction studies. The dried gels exhibit porous network morphology. Thermoreversible gel of PVF2 in diethyl azelate is also exploited to create multiporous polymer foam. Porosity measurements with the dried PVF2 gels using Mercury intrusion porosimetry and nitrogen sorption ensure the presence of macro and mesopores in the same matrix although the mesoporosity in dried PVF2‐CP gels strongly depend on method of drying.
Urinary nerve growth factor levels are elevated in patients with overactive bladder and do not significantly increase with bladder distention
Authors: Liu Hsin‐Tzu , Kuo Hann‐Chorng
Published: December 2008

Aims

Urinary nerve growth factor (NGF) levels have been found to be higher in patients with overactive bladder (OAB) compared to normal controls. This study investigated the effect of bladder volume on urinary NGF production in normal controls and patients with OAB.

Methods

Urinary NGF levels were measured in 39 patients with OAB and in 35 control subjects without lower urinary tract symptoms (LUTS). Urine samples were collected at the first sensation of bladder filling (FSF) and at urge sensation (US), respectively, in both groups. Measurement of urinary NGF levels was performed by ELISA method and normalized by urinary creatinine concentration (NGF/Cr). The correlation between NGF/Cr level and increased bladder volume was analyzed.

Results

Urinary NGF/Cr levels in normal controls were very low at FSF (mean ± standard error, 0.011 ± 0.008) and were significantly higher at US (0.086 ± 0.022, P = 0.005). Patients with OAB had significantly higher urinary NGF/Cr levels both at FSF (0.45 ± 0.13, P = 0.001) and US (1.00 ± 0.32, P = 0.004) compared to controls. The difference in urinary NGF/Cr levels between FSF and US in OAB patients, however, was not significant (P = 0.064).

Conclusions

Urinary NGF/Cr level was well correlated with bladder volume at US in the controls but not significant associated with bladder volume increase in patients with OAB. The results of this study suggest urinary NGF increases physiologically in normal subjects at urge to void but is pathologically elevated in OAB patients at small bladder volume and does not significantly increase at urgency sensation. Neurourol. Urodynam. 28:78–81, 2009. © 2008 Wiley‐Liss, Inc.
Assumed‐deformation gradient finite elements with nodal integration for nearly incompressible large deformation analysis
Authors: Broccardo M. , Micheloni M. , Krysl P.
Published: December 2008

An assumed‐strain finite element technique for non‐linear finite deformation is presented. The weighted‐residual method enforces weakly the balance equation with the natural boundary condition and also the kinematic equation that links the elementwise and the assumed‐deformation gradient. Assumed gradient operators are derived via nodal integration from the kinematic‐weighted residual. A variety of finite element shapes fits the derived framework: four‐node tetrahedra, eight‐, 27‐, and 64‐node hexahedra are presented here. Since the assumed‐deformation gradients are expressed entirely in terms of the nodal displacements, the degrees of freedom are only the primitive variables (displacements at the nodes). The formulation allows for general anisotropic materials and no volumetric/deviatoric split is required. The consistent tangent operator is inexpensive and symmetric. Furthermore, the material update and the tangent moduli computation are carried out exactly as for classical displacement‐based models; the only deviation is the consistent use of the assumed‐deformation gradient in place of the displacement‐derived deformation gradient. Examples illustrate the performance with respect to the ability of the present technique to resist volumetric locking. A constraint count can partially explain the insensitivity of the resulting finite element models to locking in the incompressible limit. Copyright © 2008 John Wiley & Sons, Ltd.
Modulation of electronic structures of thienylene vinylene oligomers by substituents and solvents: ground and excited states
Authors: Meng Suci , Jiang Jie , Wang Yujuan , Ma Jing
Published: December 2008

The effects of substituents on the electronic structures of di(thienylene vinylene) (2TV) in ground and excited states are studied using density functional theory (DFT) and time‐dependent DFT (TD‐DFT), respectively. A representative set of electron donating groups (amino, methoxy and methyl) and withdrawing groups (acetylene, cyano and nitro) are introduced on the vinylene and thienyl moieties to investigate the influence of substituents. Bulk solvent effects are also taken into account by means of the polarizable continuum model (PCM). In contrast to the aromatic structures of 2TV and its derivatives in their ground (S0) states, the electronic structures of first singlet excited (S1) states are rather delocalized. The electron‐donating/withdrawing capability, position and number of substituents are important factors in tuning the vertical S0 → S1 absorption energies and S1 → S0 emission energies of 2TV derivatives. The NO2‐ and NH2‐substituents exert significant effects on the geometries of both ground and excited states and hence the absorption and photoluminescence (PL) emission spectra. The solvent polarity introduces modest influence on the excitation energies for most of the 2TV derivatives. But the absorption and PL emission spectra of nitro‐substituted 2TV exhibit noticeable red shifts as the medium polarity increases. Copyright © 2008 John Wiley & Sons, Ltd.
Theoretical studies on the electronic and optical properties of arene‐ versus fluoroarene‐thiophene co‐oligomer
Authors: Ran Xue‐Qin , Feng Ji‐Kang , Ren Ai‐Min , Tian Wei Quan , Zou Lu‐Yi , Liu Yan‐Ling , Sun Chia‐Chung
Published: December 2008

A series of regiochemically varied and core size extension‐modulated arene‐ and fluoroarene‐thiophene co‐oligomers and the unsubstituted sexithiophene α6T were investigated theoretically to explore their electronic and optical properties. These phenylene‐thiophene oligomers show great potential for application in organic light‐emitting diodes (OLEDs), organic diode lasers, and organic thin‐film transistors (OTFTs) because of their feasible tuning of optical and electronic properties by the various structural tunings. Density functional theory (DFT) and the ab initio HF were employed to investigate the geometric and electronic structures of the oligomers in the ground state, and the singles configuration interaction (CIS) methods were used to study the lowest singlet excited state. The lowest excitation energies (Egs), the radiative lifetime τ, and the maximal absorption/emission wavelength of the oligomers were studied within time‐dependent DFT (TDDFT). All calculations were performed using the 6‐31G(d) basis set. The results show that the HOMOs, LUMOs, energy gaps, ionization potentials (IPs), electron affinities (EAs), and reorganization energies are significantly affected by the various structural tunings in these co‐oligomers, which is important for the improvement of the hole and electron injection into OLEDs. Interestingly, the LUMO energy of 1b, 2b, and 3b is lower than that of α6T and 1a, 2a, 3a by about 0.12 ∼ 0.47 eV, indicating that the fluorophenyl‐substitution has significantly improved the electron injection properties of the oligomers. Copyright © 2008 John Wiley & Sons, Ltd.
Pulsed Plasma Deposition from Vinyltrimethylsilane/Oxygen Mixtures
Authors: Francescangeli Adriano , Palumbo Fabio , d'Agostino Riccardo , Defranoux Christophe
Published: December 2008

In this work, SiO2‐like films have been deposited in a capacitive coupled parallel plate reactor using low pressure, pulsed O2/VTMS plasmas. The influence of the duty cycle and of the period on the structure of films at fixed gas feed composition are shown. It has been demonstrated that the chemical process developed depends very much on the modulation parameters, and that the OFF time significantly contributes to the overall process kinetics. Furthermore, some indication have been obtained on the possibility of getting multistack gas barrier coatings by alternating organic and inorganic layers, in which the inorganic layer is deposited by means of modulated plasma processes based on vinyltrimethylsilane feeds.

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Formation of Plasma‐Polymerized Top Layers on Composite Membranes: Influence on Separation Efficiency
Authors: Tran Dung Thi , Mori Shinsuke , Tsuboi Daisuke , Suzuki Masaaki
Published: December 2008

Plasma‐polymerized reverse osmosis membranes were prepared by deposition of an allylamine plasma‐polymerized top layer onto a cellulose ester surface. Their separation performance was highly dependent on the formation of the top layer, which was itself determined by the plasma polymerization conditions. The density and the thickness of the plasma‐deposited polymer top layer influence the membrane flux, while the ability of the membrane to reject salt relies on the degree of polymer cross‐linking, which is in turns related to the transfer of plasma energy into monomer molecules during plasma polymerization. The separation efficiency of the multilayer reverse osmosis composite membrane can be optimized by choosing appopriate plasma conditions.

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Thymoquinone protects dopaminergic neurons against MPP+ and rotenone
Authors: Radad Khaled , Moldzio Rudolf , Taha Mokhtar , Rausch Wolf‐Dieter
Published: December 2008

Thymoquinone is the main active constituent of Nigella sativa seeds with antioxidant and antiinflammatory properties. In the present study, primary dopaminergic cultures from mouse mesencephala were used to investigate the neuroprotective effects of thymoquinone against MPP+ and rotenone toxicities. MPP+ (10 µm on day 10 in vitro (i.v.) for 48 h) significantly decreased the number of THir by 40% compared with untreated control cultures. Rotenone at both short (20 nm on day 10 i.v. for 48 h) and long‐term (1 nm on day 6 i.v. for 6 consecutive days) toxicities reduced the number of THir neurons by 33% and 24%, respectively. Treatment of cultures with thymoquinone (0.01, 0.1, 1, 10 µm on day 8 i.v. for 4 days) rescued about 25% of THir neurons at concentrations of 0.1 µm and 1 µm against MPP+‐induced cell death. Against rotenone, thymoquinone afforded significant protection in both short‐ and long‐term models. In short‐term rotenone toxicity, thymoquinone (from days 8–12 i.v.) saved about 65%, 74% and 79% of THir neurons at concentrations of 0.01, 0.1 and 1 µm, respectively, compared with cell loss induced by rotenone. In long‐term rotenone toxicity, concomitant treatment of cultures with thymoquinone significantly rescued about 83–100% of THir neurons compared with rotenone‐treated cultures. In conclusion, the current study presents for the first time the potential of thymoquinone to protect primary dopaminergic neurons against MPP+ and rotenone relevant to Parkinson's disease. Copyright © 2008 John Wiley & Sons, Ltd.
A new approach to aid the characterisation and identification of metabolites of a model drug; partial isotope enrichment combined with novel formula elucidation software
Authors: Hobby Kirsten , Gallagher Richard T. , Caldwell Patrick , Wilson Ian D.
Published: December 2008

This work describes the identification of ‘isotopically enriched’ metabolites of 4‐cyanoaniline using the unique features of the software package ‘Spectral Simplicity’. The software is capable of creating the theoretical mass spectra for partially isotope‐enriched compounds, and subsequently performing an elemental composition analysis to give the elemental formula for the ‘isotopically enriched’ metabolite. A novel mass spectral correlation method, called ‘FuzzyFit’, was employed. ‘FuzzyFit’ utilises the expected experimental distribution of errors in both mass accuracy and isotope pattern and enables discrimination between statistically probable and improbable candidate formulae. The software correctly determined the molecular formulae of ten previously described metabolites of 4‐cyanoaniline confirming the technique of partial isotope enrichment can produce results analogous to standard methodologies. Six previously unknown species were also identified, based on the presence of the unique ‘designer’ isotope ratio. Three of the unknowns were tentatively identified as N‐acetylglutamine, O‐methyl‐N acetylglucuronide and a putative fatty acid conjugate. The discovery of a significant number of unknown species of a model drug with a comprehensive history of investigation highlights the potential for enhancement to the analytical process by the use of ‘designer’ isotope ratio compounds. The ‘FuzzyFit’ methodology significantly aided the elucidation of candidate formulae, by provision of a vastly simplified candidate formula data set. Copyright © 2008 John Wiley & Sons, Ltd.
Extracting metabolite ions out of a matrix background by combined mass defect, neutral loss and isotope filtration
Authors: Cuyckens Filip , Hurkmans Rob , Castro‐Perez Jose M. , Leclercq Laurent , Mortishire‐Smith Russell J.
Published: December 2008

Mass defect, neutral loss and isotope filtration techniques were applied to electrospray ionization mass spectrometry (ESI‐MS) data obtained for in vivo and in vitro samples of drug metabolism studies. A combination of these post‐acquisition processing techniques was shown to be more powerful than the use of one of these tools alone for the detection in complex matrices of metabolites of candidate drugs with a characteristic isotope pattern (e.g. containing bromine, chlorine, or a high proportion of radiolabeled drug (12C/14C)) or characteristic neutral losses. In combination with ‘all‐in‐one’ data acquisition this methodology is able to perform software‐driven constant neutral loss scanning for an unlimited number of mass differences at any time after analysis. Highly selective MS chromatograms were obtained with excellent correlation with their corresponding radiochromatograms. Copyright © 2009 John Wiley & Sons, Ltd.
Inhibition of Tumor‐Cell Invasion with Chlorotoxin‐Bound Superparamagnetic Nanoparticles
Authors: Veiseh Omid , Gunn Jonathan W. , Kievit Forrest M. , Sun Conroy , Fang Chen , Lee Jerry S. H. , Zhang Miqin
Published: December 2008

Nanoparticles have been investigated as drug delivery vehicles, contrast agents, and multifunctional devices for patient care. Current nanoparticle‐based therapeutic strategies for cancer treatment are mainly based on delivery of chemotherapeutic agents to induce apoptosis or DNA/siRNA to regulate oncogene expression. Here, a nanoparticle system that demonstrates an alternative approach to the treatment of cancers through the inhibition of cell invasion, while serving as a magnetic resonance and optical imaging contrast agent, is presented. The nanoparticle comprises an iron oxide nanoparticle core conjugated with an amine‐functionalized poly(ethylene glycol) silane and a small peptide, chlorotoxin (CTX), which enables the tumor cell‐specific binding of the nanoparticle. It is shown that the nanoparticle exhibits substantially enhanced cellular uptake and an invasion inhibition rate of ∼98% compared to unbound CTX (∼45%). Significantly, the investigation from flow cytometry analysis, transmission electron microscopy, and fluorescent imaging reveals that the CTX‐enabled nanoparticles deactivated the membrane‐bound matrix metalloproteinase 2 (MMP‐2) and induced increased internalization of lipid rafts that contain surface‐expressed MMP‐2 and volume‐regulating ion channels through receptor‐mediated endocytosis, leading to enhanced prohibitory effects. Since upregulation and activity of MMP‐2 have been observed in tumors of neuroectodermal origin, and in cancers of the breast, colon, skin, lung, prostate, ovaries, and a host of others, this nanoparticle system can be potentially used for non‐invasive diagnosis and treatment of a variety of cancer types.
Strain‐Driven Self‐Assembled Network of Antidots in Complex Oxide Thin Films
Authors: Konstantinović Zorica , Santiso José , Balcells Lluis , Martínez Benjamín
Published: December 2008

Structural strain due to lattice mismatch is used to promote the formation of a self‐assembled network of antidots in highly epitaxial La2/3Sr1/3MnO3 thin films grown on (001) oriented SrTiO3 substrates by radiofrequency magnetron sputtering. Size, depth, and separation between antidots can be controlled by changing deposition parameters and the miscut angle of the substrate. This morphology exhibits a remarkable magnetic anisotropy and offers unique opportunities for versatile nanostencils for the preparation of nano‐object networks that can be of major relevance for the fabrication of oxide‐based magnetic and magnetoelectronic devices.
Influence of Cassava Storage Root Development and Environmental Conditions on Starch Granule Size Distribution
Authors: Teerawanichpan Prapapan , Lertpanyasampatha Manassawe , Netrphan Supatcharee , Varavinit Saiyavit , Boonseng Opas , Narangajavana Jarunya
Published: December 2008

Among starch producing crops, cassava has a higher carbohydrate production than others under suboptimal conditions, more than 163×106 t of cassava starch are produced world‐wide each year and are used for direct human consumption, animal feeds and as raw material for a wide range of industrial products. A basic knowledge of starch characteristics and storage process is required to improve cassava starch quality and quantity. This report describes a comparative study of morphology, starch granule size distribution and amylose content in cassava storage roots grown under different conditions. Microscopic evaluation reveals that storage roots contain larger starch granules than fibrous roots. The study on three Asian cassava cultivars demonstrates the increment of starch granule size from outermost to innermost layers of storage root, while no significant change is observed in amylose content. The effects of developmental stage and growing season on cassava starch reveals that granule size is significantly influenced by both factors, while the amylose contents only fluctuate in a narrow range. The size of the starch granules increases particularly in the first six months after cultivation. Planting cassava in the beginning of the wet season in Asia yields larger granule sizes than planting in the dry season. The significance of this study lies in better understanding optimal growing conditions for improved starch characteristics and production, leading to a better quality agricultural production of this important food and materials crop.
Treatment of Diffuse Pigmented Villonodular Synovitis of the Knee with Combined Surgical and Radiosynovectomy
Authors: Nassar Wael A. M. , Bassiony Ayman Abdelaziz , Elghazaly Hesham A.
Published: December 2008

Treatment of extensive diffuse pigmented villonodular synovitis (PVNS) of large joints by isolated surgical resection is unsatisfactory, with high rates of local recurrence. Post-synovectomy adjuvant treatment with external beam radiation therapy or intra-articular injection of radioactive material as yttrium-90 (90Y) yielded better results. Between January 2005 and January 2007, 12 patients (eight men and four women aged 19–49 years) with extensive diffuse PVNS of the knee were treated. All patients had an adjuvant post-operative external beam radiation therapy (2,600–3,000 cGy) conventionally fractionated 200 cGy/fraction, five fractions/week, 6–8 weeks after surgery. Mean follow-up time was 27 months (range from 20 to 36 months). All patients were followed up using clinical assessment, magnetic resonance imaging, and plain X-ray. In all patients, neither evidence of disease recurrence nor progression of bone or articular destruction was noted. No complications were noticed after surgery or after post-operative external beam radiation therapy. A combination of debulking surgery using anterior and posterior approach with adjuvant post-operative external beam radiation therapy for extensive diffuse PVNS of the knee joint is a reliable treatment method, with good results in regard to the incidence of local recurrence and functional outcome.
Chronic kidney disease with three cases of oxalate-like nephrosis in Ragdoll cats
Authors: Heiene Reidun , Rumsby Gill , Ziener Martine , Dahl Stein A. , Tims Christopher , Teige Jon , Ottesen Nina
Published: December 2008

Two unrelated Ragdoll cat mothers in Norway were found dead from renal disease. The histopathology was consistent with oxalate nephrosis with chronic or acute-on-chronic underlying kidney disease. Both cats had offspring and relatives with signs of urinary tract disease, including a kitten dead with urethral gravel. Eleven living Ragdoll cats, including nine relatives of the dead cats and the male father of a litter with similarly affected animals, were tested for primary hyperoxaluria (PH) type 1 and 2 by urine oxalate and liver enzyme analysis. Renal ultrasound revealed abnormalities in five living cats. One of these was azotaemic at the time of examination and developed terminal kidney disease 9 months later. A diagnosis of PH was excluded in 11 cats tested. The inheritance and aetiological background of the renal disease present in the breed remains unresolved at this point in time.