bluuebunny/crossref_metadata_2025_split huggingface dataset:
Substituent effect on electron affinity, gas‐phase basicity, and structure of monosubstituted propynyl radicals and their anions: A theoretical study
Authors: Lee Gab‐Yong 
Published: February 2009

AbstractThe substituent effect of electron‐withdrawing groups on electron affinity and gas‐phase basicity has been investigated for substituted propynl radicals and their corresponding anions. It is shown that when a hydrogen of the α‐CH3 group in the propynyl system is substituted by an electron‐withdrawing substituent, electron affinity increases, whereas gas‐phase basicity decreases. These results can be explained in terms of the natural atomic charge of the terminal acetylene carbon of the systems. The calculated electron affinities are 3.28 eV (•CCCH2F), 3.59 eV (•CCCH2Cl) and 3.73 eV (•CCCH2Br), and the gas‐phase basicities of their anions are 359.5 kcal/mol (−:CCCH2F), 354.8 kcal/mol (:CCCH2Cl) and 351.3 kcal/mol (−:CCCH2Br). It is concluded that the larger the magnitude of electron‐withdrawing, the greater is the electron affinity of radical and the smaller is the gas‐phase basicity of its anion. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
Condensation of substituted 2‐aminopyridine with β‐ketocarboxylic esters: 4H‐pyrido[1,2‐a]pyrimidin‐4‐ones and pyridin‐2‐ones
Authors: Ferrarini Pier Luigi , Mori Claudio , Manera Clementina , Mori Filippo , Calderone Vincenzo , Martinotti Enrica 
Published: February 2009

AbstractWe report the condensation of substituted 2‐aminopyridines 5 with β‐ketocarboxylic esters in polyphosphoric acid. In this reaction were obtained together with the target compounds, 4H‐pyrido[1,2‐a]pyrirnidin‐4‐ones 6 also the pyridin‐2‐ones 7. All the compounds 7 were tested for their calcium‐antagonistic activity but failed to evoke any vasorelaxant response.
Synthesis of quinolines by ruthenium‐catalyzed heteroannulation of anilines with 3‐amino‐1‐propanol
Authors: Cho Chan Sik , Oh Byoung Ho , Shim Sang Chul 
Published: February 2009

AbstractAnilines react with 3‐amino‐1‐propanol in dioxane in the presence of a catalytic amount of a ruthenium catalyst and tin(II) chloride dihydrate together with a hydrogen acceptor to afford the corresponding quinolines in moderate yields.
Synthesis and application of ethyl 3‐(4‐dialkylaminophenyl)‐2‐(quinoxalin‐3(4H)‐on‐2‐yl)propenoates and related products
Authors: Rangnekar D. W. , Kanetkar V. R. , Shankarling G. S. , Malanker J. V. , Shanbhag C. R. 
Published: February 2009

AbstractEthyl quinoxalin‐3(4H)‐on‐2‐ylacetate was prepared by the condensation of 1,2‐diaminobenzene and diethyl oxalacetate (sodium salt). The key quinoxaline intermediate was condensed with a variety of 4‐dialkylaminobenzaldehydes/substituted benzaldehydes to yield novel brilliant quinoxalin‐2‐yl styryl dyes which were applied on polyester fibers as disperse dyes and their dyeing properties were studied.
Attempted syntheses of aminofluorothiophenes
Authors: Kobarfard Farzad , Kauffman Joel M. , Boyko Walter J. 
Published: February 2009

AbstractIt appeared that a key intermediate for 2‐amino‐3‐fluorothiophene (1), methyl 3‐fluorothiophene‐2‐carboxylate (5), had been prepared by a Schiemann reaction of the 3‐diazonium salt (6) in xylenes. This report was not correct. Gomberg coupling products 7 with o‐xylene are actually formed. We were able to prepare 5 by using special conditions for the Schiemann reaction. The hydrazide derivative of 5 failed to give 1 under Curtius reaction conditions. Two new acetamidofluorothiophene compounds were prepared using SelectfluorTM as the fluorinating agent, but no aminofluorothiophenes 1‐3 or salts could be obtained by acidic hydrolysis of either amide.
Synthesis of crown ethers containing a thiazole subcyclic unit
Authors: Kim Hong‐Seok , Kwon Ii‐Chun , Choi Jun‐Hyeak 
Published: February 2009

AbstractCrown ethers containing a thiazole subcyclic unit are prepared from the reactions of 1,3‐bis[2(4‐hydroxymethylthiazoyl)]benzene with di‐p‐tosylates of corresponding di, tri, tetra, pentaethylene glycols in the presence of potassium hydride. However, if the cavity size in the ring system is small, [2+2] cyclization adduct also is formed.
Synthesis of bipyrazoles and pyrazoloisoxazoles from 3‐acetyl‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one
Authors: Bendaas Abderrahman , Hamdi Maâmar , Sellier Nicole 
Published: February 2009

AbstractPhenylhydrazine or hydrazine react with 3‐acetyl‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one (1) to give 4‐acetoacetyl‐3‐methylpyrazolin‐5‐ones 4. The synthesis of bipyrazoles and pyrazoloisoxazoles from 4 are reported.
Synthesis of [1,4]dioxino[2,3‐c]quinolines and [1,4]dioxepino‐[2,3‐c]quinolines and their 1‐sulfur analogues
Authors: Hiessböck Romana , Kratzel Martin 
Published: February 2009

AbstractThe synthesis of [1,4]dioxino[2,3‐c]quinolines and [1,4]dioxepino[2,3‐c]quinolines with restrained conformation of the piperidine ring, which represent 1,2,3,4‐tetrahydroquinolines containing two heteroatom substituents at positions 3 and 4, is described. In addition, the application of this approach for the synthesis of 1‐sulfur analogues is discussed. Both series are helpful tools for three‐dimensional quantitative structure‐activity relationship studies in the field of modulators of multidrug resistance.
Molecular structures, electronic spectra, and aromaticity of 1,6‐ and 1,8‐dioxa analogues of pyrene and benzo[a]pyrene. Semiempirical molecular orbital calculations
Authors: Kataoka Masahiro , Sato Tsuguo 
Published: February 2009

AbstractThe molecular structures of [1]benzopyrano[6,5,4‐def][1]benzopyran, [2]benzopyrano[7,8,1,def]‐1‐benzopyran, 1‐benzopyrano[6,5,4‐mna]xanthene, and 2‐benzopyrano[7,8,1‐mna]xanthene have been optimized by using the PM3 semiemperical MO method. These calculated molecules have been shown to be planar. Their aromaticity has been investigated by use of the HOMA index. The molecules are found to be less aromatic than the correspolding parednt hydrocarbons, pyrene and benzo[a]pyrene. The CNDO/S MO method has been used to interpret th experimental uv‐vis specrtoscopic data. The result of the PM3, CNDO/S and HOMA‐index clculations are in good arteement with the experimental data.
Synthesis of a‐ and d‐homoazasteroidalisoxazoles
Authors: Xenos Constantinos D. , Camoutsis Charalambos 
Published: February 2009

AbstractThe synthesis of the isomeric D‐homoazasteroido[3,2‐c]‐ (3) and ‐[2,3‐d]lisoxazoles (4) and A‐homoazasteroido[17,16‐c]isoxazole (6) are reported by the reaction of 2‐hydroxymethylene‐17α‐aza‐D‐homo‐5α‐androstan‐3,17‐dione (2) and 16‐hydroxymethylene‐3‐aza‐A‐homo‐4α‐androsten‐4,17‐dione (5) correpondingly with hydroxylammonium chloride.
Biological activation of bone‐related biomaterials by recombinant adeno‐associated virus vector
Authors: Nasu Tomonori , Ito Hiromu , Tsutsumi Ryosuke , Kitaori Toshiyuki , Takemoto Mitsuru , Schwarz Edward M. , Nakamura Takashi 
Published: February 2009

AbstractGene therapy is a promising clinical tool that is no longer limited as a method to supplement genetic deficits, but rather is considered reliable for delivering proteins to specific tissues or cells. Recombinant adeno‐associated virus (rAAV) vector is one of the most potent gene transfer vehicles. Many biomaterials have been used in reconstructive surgery, but their biological inactivity has limited their use. To overcome shortcomings of available bone‐related biomaterials, we investigated the combination of rAAV with biomaterials. Taking advantage of the method of lyophilizing rAAV onto biomaterials, we showed that an rAAV coating successfully induced β‐galactosidase protein expression by rat fibroblasts on hydroxyapatite, β‐tricalcium phosphate, and titanium alloy in vitro. β‐Galactosidase expression was detected for 8 weeks after implantation of rAAV‐coated hydroxyapatite into rat back muscles in vivo. A coating of bone morphogenetic protein‐2‐expressing rAAV induced significant de novo bone formation on hydroxyapatite in rat back muscles. Our study demonstrates that the combination of lyophilized rAAV and biomaterials presents a promising strategy for bone regenerative medicine. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Longer Waiting Times for Obese Liver Transplant Patients
Authors: Perkins James D. 
Published: February 2009

Abstract

Objective:
To quantify the independent association between obesity and access to liver transplantation.

Background:
Obesity is associated with higher complication rates, longer hospitalization, and worse survival after liver transplantation. Nevertheless, transplantation provides survival benefit to patients with end-stage liver disease, regardless of body mass index (BMI). We hypothesized that, despite survival benefit, providers were reluctant to transplant obese patients because of the inherent difficulty of these cases and their inferior outcomes. Our goal was to quantify the independent association between BMI and waiting time for orthotopic liver transplantation as a surrogate marker for this reluctance.

Methods:
We studied 29,136 wait-list candidates in the model for end-stage liver disease (MELD) era, categorized as severely obese (BMI 35-40), morbidly obese (BMI 40-60), and reference (BMI 18.5-35). All models were adjusted for factors relevant to the allocation system, factors possibly influencing access to healthcare, and factors biologically related to disease progression and outcomes.

Results:
The odds of receiving a MELD exception were 30% lower in severely obese and 38% lower in morbidly obese patients. Similarly, the likelihoods of being turned down for an organ were 10% and 16% higher, and the rates of being transplanted were 11% and 29% lower in severely obese and morbidly obese patients, respectively.

Conclusions:
Current practice seems to indicate a reluctance to transplant obese patients. If indeed as a community we feel that liver allografts should not be distributed to patients with excessive postoperative risk, we should consider expressing this as a formal change to our allocation policy rather than through informal practice patterns.
Laser ablation‐inductively coupled plasma mass spectrometry in archaeometric research
Authors: Resano Martín , García‐Ruiz Esperanza , Vanhaecke Frank 
Published: February 2009

AbstractLaser ablation‐inductively coupled plasma mass spectrometry (LA‐ICPMS) is a solid sampling technique in continuous expansion in all types of research fields in which direct multi‐elemental or isotopic analysis is required. In particular, this technique shows unique characteristics that made its use recommended in many archaeometric applications, where valuable solid artifacts are often the target samples, because it offers flexibility to achieve spatially resolved information with high detection power and a wide linear range, in a fast and straightforward way, and with minimal sample damage. The current review provides a systematic survey of publications that reported the use of LA‐ICPMS in an archaeological context, highlights its main capabilities and limitations and discusses the most relevant parameters that influence the performance of this technique for this type of application. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:55–78, 2010
Questionnaire‐based assessment of pelvic organ dysfunction in multiple system atrophy
Authors: Yamamoto Tatsuya , Sakakibara Ryuji , Uchiyama Tomoyuki , Liu Zhi , Ito Takashi , Awa Yusuke , Yamanishi Tomonori , Hattori Takamichi 
Published: February 2009

AbstractMultiple system atrophy (MSA) is a neurodegenerative disease characterized clinically by any combination of autonomic, cerebellar, and extrapyramidal symptoms. Autonomic symptoms are usually severe, and urinary symptoms are one of the cardinal features of MSA. Bowel dysfunction and sexual dysfunction are also common in MSA. Quality of life (QOL) in patients with MSA is severely impaired by the presence of pelvic organ dysfunction. Therefore, we aimed to examine the prevalence of pelvic organ dysfunction in patients with MSA. We recruited 256 patients with MSA seen at our neurology clinic. The mean age was 62 years. The control group comprised 158 individuals, and the mean age was 52 years. We administered a questionnaire on pelvic organ dysfunction to the MSA and control groups. The questionnaire had sections focusing on the bladder, bowel, and sexual function. Dysfunction, as described in the responses, was evaluated as normal, mild (>once a month), moderate (>once a week), or severe (>once a day). The Mann‐Whitney's U‐test was used for statistical analysis. When compared with the control group, the prevalence of pelvic organ dysfunction in the MSA group was significantly higher for urinary storage and voiding dysfunction, bowel dysfunction, and sexual dysfunction. QOL in the MSA group was therefore significantly impaired because of urinary dysfunction (70%, 76%), bowel dysfunction (40% of the men), and sexual dysfunction (26%, 45%). Pelvic organ dysfunction is common in MSA, and QOL is severely impaired in patients with MSA. © 2009 Movement Disorder Society
Description of a family with a novel progressive myoclonus epilepsy and cognitive impairment
Authors: Ferlazzo Edoardo , Italiano Domenico , An Isabelle , Calarese Tiziana , Laguitton Virginie , Bramanti Placido , Di Bella Paolo , Genton Pierre 
Published: February 2009

AbstractWe report a family of Algerian origin presenting an unusual, severe form of progressive myoclonus epilepsy characterized by myoclonus, generalized tonic‐clonic seizures and moderate to severe cognitive impairment, with probable autosomal recessive inheritance. Disease onset was between 6 and 16 years of age. The diagnosis of Unverricht‐Lundborg disease and all other known causes of progressive myoclonus epilepsies were excluded by specific laboratory tests and molecular analysis. © 2009 Movement Disorder Society
Deterministic chaos in a model of discrete manufacturing
Authors: Bartholdi John J. , Eisenstein Donald D. , Lim Yun Fong 
Published: February 2009

AbstractA natural extension of the bucket brigade model of manufacturing is capable of chaotic behavior in which the product intercompletion times are, in effect, random, even though the model is completely deterministic. This is, we believe, the first proven instance of chaos in discrete manufacturing. Chaotic behavior represents a new challenge to the traditional tools of engineering management to reduce variability in production lines. Fortunately, if configured correctly, a bucket brigade assembly line can avoid such pathologies. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009
What you should know about approximate dynamic programming
Authors: Powell Warren B. 
Published: February 2009

AbstractApproximate dynamic programming (ADP) is a broad umbrella for a modeling and algorithmic strategy for solving problems that are sometimes large and complex, and are usually (but not always) stochastic. It is most often presented as a method for overcoming the classic curse of dimensionality that is well‐known to plague the use of Bellman's equation. For many problems, there are actually up to three curses of dimensionality. But the richer message of approximate dynamic programming is learning what to learn, and how to learn it, to make better decisions over time. This article provides a brief review of approximate dynamic programming, without intending to be a complete tutorial. Instead, our goal is to provide a broader perspective of ADP and how it should be approached from the perspective of different problem classes. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009
Analysis of fluid‐structure interaction in low pressure MEMS by Integral Equations
Authors: Frangi Attilio 
Published: February 2009

AbstractThe evaluation of gas dissipation occurring in inertial polysilicon MEMS is addressed focusing the attention on the free–molecule flow. In this regime, which is very often of interest for industrial applications, collisions between molecules can be neglected and the momentum transfer to the moving shuttle can be easily computed. Since the surfaces of silicon MEMS are generally very rough, a complete diffusion model is adopted to describe the wall–molecule interaction. A Boundary Integral Equation approach is proposed and it is shown that the introduction of the key assumption of small perturbations is crucial in the development of a robust and fast numerical tool. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Application of gradient based algorithms for robust shape optimization of a tensile test specimen
Authors: Abel Bengt , Schumacher Axel , Bartsch Marion 
Published: February 2009

AbstractIn case of technical applications such as automotive or aeronautic part optimization, uncertainties in design variables and other parameters have to be taken into account. Especially, scattering of material properties and mechanical loads have large influences on the component behavior.Due to the difficulty in calculating of sensitivities, usually stochastic algorithms are used for robust and reliability optimization. That entails a large number of function calls and long computation time. Therefore, the stochastic responses with expectation value and variances will be approximated by response surfaces in this contribution. Based on the practical example of a tensile test specimen a deterministic optimization and optimization under uncertainties will be done. The results of the different optimizations will be compared and the influence of the uncertainties will be shown and discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
New adaptive mixed finite element method (AMFEM)
Authors: Carstensen Carsten , Rabus Hella 
Published: February 2009

AbstractThe need to develop reliable and efficient adaptive algorithms using mixed finite element methods arises from various applications in fluid dynamics and computational continuum mechanics. In order to save degrees of freedom, not all but just some selected set of finite element domains are refined and hence the fundamental question of convergence requires a new mathematical argument as well as the question of optimality.We will present a new adaptive algorithm for mixed finite element methods to solve the model Poisson problem, for which optimal convergence can be proved. The a posteriori error control of mixed finite element methods dates back to Alonso (1996) Error estimators for a mixed method. and Carstensen (1997) A posteriori error estimate for the mixed finite element method. The error reduction and convergence for adaptive mixed finite element methods has already been proven by Carstensen and Hoppe (2006) Error Reduction and Convergence for an Adaptive Mixed Finite Element Method, Convergence analysis of an adaptive nonconforming finite element methods.Recently, Chen, Holst and Xu (2008) Convergence and Optimality of Adaptive Mixed Finite Element Methods. presented convergence and optimality for adaptive mixed finite element methods following arguments of Rob Stevenson for the conforming finite element method. Their algorithm reduces oscillations, before applying and a standard adaptive algorithm based on usual error estimation. The proposed algorithm does this in a natural way, by switching between the reduction of either the estimated error or oscillations. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
hp‐Adaptive Finite Element Methods for Variational Inequalities
Authors: Schröder Andreas 
Published: February 2009

AbstractIn this work, we combine an hp–adaptive strategy with a posteriori error estimates for variational inequalities, which are given by contact problems. The a posteriori error estimates are obtained using a general approach based on the saddle point formulation of contact problems and making use of a yposteriori error estimates for variational equations. Error estimates are presented for obstacle problems and Signorini problems with friction.Numerical experiments confirm the reliability of the error estimates for finite elements of higher order. The use of the hp–adaptive strategy leads to meshes with the same characteristics as geometric meshes and to exponential convergence. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlinear Model Order Reduction in Nanoelectronics: Combination of POD and TPWL
Authors: Bechtold T. , Striebel M. , Mohaghegh K. , ter Maten E. J. W. 
Published: February 2009

AbstractIn this paper we demonstrate model order reduction of a nonlinear academic model of an inverter chain. Two reduction methods, which are suitable for nonlinear differential algebraic equation systems are combined, the trajectory piecewise linear approach and the proper orthogonal decomposition. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dynamical iteration schemes for coupled simulation in nanoelectronics
Authors: Culpo Massimiliano , de Falco Carlo 
Published: February 2009

AbstractIn this paper we present an approach to coupled electro–thermal circuit simulation. More precisely we derive from the heat diffusion PDE a thermal element model and we show how it can be included in a standard SPICE–like circuit simulator without significant modifications to the solver structure. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polynomial Chaos for Analysing Periodic Processes of Differential Algebraic Equations with Random Parameters
Authors: Pulch Roland 
Published: February 2009

AbstractMathematical models of dynamical systems typically include technical parameters. Assuming an uncertainty, some parameters are replaced by random variables and the solution of the time–dependent system becomes a stochastic process. We consider forced oscillators, which are modelled by systems of differential algebraic equations. Consequently, periodic boundary conditions are imposed on the system. We apply the technique of the generalised polynomial chaos to resolve the stochastic model. Numerical simulations based on the electric circuit of a transistor amplifier are presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Experimental investigation of a moored floating system
Authors: Beyer Daniel , Ellermann Katrin 
Published: February 2009

AbstractFloating structures are generally excited by a more or less irregular sea state. Therefore the structure undergoes a nonlinear dynamical behaviour which results from hydrodynamic effects or the kinematic coupling of different components. The motions of these structures have been analysed intensively with numerical techniques which predict a wide range of nonlinear effects. On the other hand, experiments are still important when it comes to verifying these theoretical findings. Investigating such a floating structure experimentally requires a complex setup: A wave generator needs to be driven in an appropriate way to yield waves with the required characteristics at the structure. The structure itself is usually designed similar to a real–world system and it has to allow for a comparison with numerical analyses. Sensors which measure the tracks of the individual components not only have to reach a prescribed precision but also need to ensure that the motion is not perturbed as a result of the measurements. Lastly, unwanted disturbances have to be avoided. For experiments in a wave tank this includes that reflections have to be minimized. This talk addresses the development of an experimental setup for the investigation of a floating structure. It highlights components which are found to be critical for the obtained accuracy and proposes techniques to reduce experimental errors. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation einfacher reibungsbehafteter Stoßkontakte
Authors: Fritz Felix , Friedrich Carl‐Christoph , Seemann Wolfgang 
Published: February 2009

AbstractUm die Eignung des kommerziellen Mehrkörperdynamikprogramms MSC/ADAMS zur Simulation von reibungsbehafteten Stoßkontakten zu untersuchen, werden einfache Schusssituationen beim Tischfußball simuliert und die Ergebnisse mit denen analytischer Stoßmodelle verglichen. Als Testsituation dient das experimentell betrachtete Phänomen, wann der Ball aus dem Tor zurückspringt, obwohl die Prallplatte getroffen wurde. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)