bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlating the surface area and synthesis conditions of block co‐polymer templated mesoporous silica
Authors: Harris A. T. , Maddocks A. R. , Braham R. J. 
Published: July 2009

AbstractIn this work we investigate the influence of (1) temperature, (2) curing (post reaction ageing) technique, (3) curing time, (4) surfactant (block co‐polymer) concentration, and (5) the addition of secondary (pore swelling) reagents on the surface area and structure of ordered hexagonal mesoporous silica (SBA‐15). We also investigate the use of microwave preparation and curing techniques, as a precursor to the development of large‐scale synthesis processes for mesoporous silica. Samples were analyzed using transmission electron microscopy and nitrogen pore size analysis. The results of the study show that it is possible to optimize the surface area of the final material in a reproducible way, by using higher hydrolysis temperatures or lower surfactant concentrations. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Using economic X control chart design methodology to estimate and optimize machine efficiency in the case of multimachine assignments
Authors: Engin A. Baki 
Published: July 2009

AbstractEstimation and optimization of machine efficiency in the case of multi machine assignments is a difficult issue for some industries such as textile industry, due to the machine interference. Although the problem is not new, the solutions proposed are not full satisfactory. For example, the analytical formulas are not suitable for high number of machines; queuing theory approaches are complex and impractical for mill managers. On the other hand, simulation methodology seems to be a perfect tool to estimate and analyze; however, the simulation package programs are expensive and are not suitable for systematic optimization. In this paper, Duncan's economic control chart design methodology is proposed as an alternative way for one of the oldest industrial problems. This study shows that this new approach is a more efficient solution to this stochastic problem. Copyright © 2009 John Wiley & Sons, Ltd.
1950 MHz IMT‐2000 field does not activate microglial cells in vitro
Authors: Hirose Hideki , Sasaki Atsushi , Ishii Nana , Sekijima Masaru , Iyama Takahiro , Nojima Toshio , Ugawa Yoshikazu 
Published: July 2009

AbstractGiven the widespread use of the cellular phone today, investigation of potential biological effects of radiofrequency (RF) fields has become increasingly important. In particular, much research has been conducted on RF effects on brain function. To examine any biological effects on the central nervous system (CNS) induced by 1950 MHz modulation signals, which are controlled by the International Mobile Telecommunication‐2000 (IMT‐2000) cellular system, we investigated the effect of RF fields on microglial cells in the brain. We assessed functional changes in microglial cells by examining changes in immune reaction‐related molecule expression and cytokine production after exposure to a 1950 MHz Wideband Code Division Multiple Access (W‐CDMA) RF field, at specific absorption rates (SARs) of 0.2, 0.8, and 2.0 W/kg. Primary microglial cell cultures prepared from neonatal rats were subjected to an RF or sham field for 2 h. Assay samples obtained 24 and 72 h after exposure were processed in a blind manner. Results showed that the percentage of cells positive for major histocompatibility complex (MHC) class II, which is the most common marker for activated microglial cells, was similar between cells exposed to W‐CDMA radiation and sham‐exposed controls. No statistically significant differences were observed between any of the RF field exposure groups and the sham‐exposed controls in percentage of MHC class II positive cells. Further, no remarkable differences in the production of tumor necrosis factor‐α (TNF‐α), interleukin‐1β (IL‐1β), and interleukin‐6 (IL‐6) were observed between the test groups exposed to W‐CDMA signal and the sham‐exposed negative controls. These findings suggest that exposure to RF fields up to 2 W/kg does not activate microglial cells in vitro. Bioelectromagnetics 31:104–112, 2010. © 2009 Wiley‐Liss, Inc.
Interpreting Statistical Evidence with Empirical Likelihood Functions
Authors: Zhang Zhiwei 
Published: July 2009

AbstractThere has been growing interest in the likelihood paradigm of statistics, where statistical evidence is represented by the likelihood function and its strength is measured by likelihood ratios. The available literature in this area has so far focused on parametric likelihood functions, though in some cases a parametric likelihood can be robustified. This focused discussion on parametric models, while insightful and productive, may have left the impression that the likelihood paradigm is best suited to parametric situations. This article discusses the use of empirical likelihood functions, a well‐developed methodology in the frequentist paradigm, to interpret statistical evidence in nonparametric and semiparametric situations. A comparative review of literature shows that, while an empirical likelihood is not a true probability density, it has the essential properties, namely consistency and local asymptotic normality that unify and justify the various parametric likelihood methods for evidential analysis. Real examples are presented to illustrate and compare the empirical likelihood method and the parametric likelihood methods. These methods are also compared in terms of asymptotic efficiency by combining relevant results from different areas. It is seen that a parametric likelihood based on a correctly specified model is generally more efficient than an empirical likelihood for the same parameter. However, when the working model fails, a parametric likelihood either breaks down or, if a robust version exists, becomes less efficient than the corresponding empirical likelihood.
A Generalized Log‐Rank‐Type Test for Comparing Survivals with Doubly Interval‐Censored Data
Authors: Kim Jinheum , Kim Yang‐Jin , Nam Chung Mo 
Published: July 2009

AbstractIn doubly interval‐censored data, the survival time of interest is defined as the elapsed time between an initial event and a subsequent event, but the occurrences of both events cannot be observed exactly. Instead, only right‐ or interval‐censored observations on the occurrence times are available. Our purpose is to develop a generalized log‐rank‐type test for comparing survival functions of several groups. For the same problem, Sun (The Statistical Analysis of Interval‐censored Failure Time Data, Springer, New York) suggested a nonparametric test based on the estimated marginal survival functions of the two related events. We consider a new method using uniform weights, which depend only on the size of the risk set at each observed time. The proposed method does not require the estimation of marginal survival functions and furthermore can reduce to the log‐rank test for right‐censored data. Results from a simulation study show that our test performs well in terms of size and power. We analyze the AIDS cohort study data taken from Kim et al. (Biometrics 49, 13–22).
Computational framework for predictive biodegradation
Authors: Finley Stacey D. , Broadbelt Linda J. , Hatzimanikatis Vassily 
Published: July 2009

AbstractAs increasing amounts of anthropogenic chemicals are released into the environment, it is vital to human health and the preservation of ecosystems to evaluate the fate of these chemicals in the environment. It is useful to predict whether a particular compound is biodegradable and if alternate routes can be engineered for compounds already known to be biodegradable. In this work, we describe a computational framework (called BNICE) that can be used for the prediction of novel biodegradation pathways of xenobiotics. The framework was applied to 4‐chlorobiphenyl, phenanthrene, γ‐hexachlorocyclohexane, and 1,2,4‐trichlorobenzene, compounds representing various classes of xenobiotics with known biodegradation routes. BNICE reproduced the proposed biodegradation routes found experimentally, and in addition, it expanded the biodegradation reaction networks through the generation of novel compounds and reactions. The novel reactions involved in the biodegradation of 1,2,4‐trichlorobenzene were studied in depth, where pathway and thermodynamic analyses were performed. This work demonstrates that BNICE can be applied to generate novel pathways to degrade xenobiotic compounds that are thermodynamically feasible alternatives to known biodegradation routes and attractive targets for metabolic engineering. Biotechnol. Bioeng. 2009; 104: 1086–1097. © 2009 Wiley Periodicals, Inc.
Role of Capping Ligands on the Nanoparticles in the Modulation of Properties of a Hybrid Matrix of Nanoparticles in a 2D Film and in a Supramolecular Organogel
Authors: Pal Asish , Srivastava Aasheesh , Bhattacharya Santanu 
Published: July 2009

AbstractWe incorporate various gold nanoparticles (AuNPs) capped with different ligands in two‐dimensional films and three‐dimensional aggregates derived from N‐stearoyl‐L‐alanine and N‐lauroyl‐L‐alanine, respectively. The assemblies of N‐stearoyl‐L‐alanine afforded stable films at the air–water interface. More compact assemblies were formed upon incorporation of AuNPs in the air–water interface of N‐stearoyl‐L‐alanine. We then examined the effects of incorporation of various AuNPs functionalized with different capping ligands in three‐dimensional assemblies of N‐lauroyl‐L‐alanine, a compound that formed a gel in hydrocarbons. The profound influence of nanoparticle incorporation into physical gels was evident from evaluation of various microscopic and bulk properties. The interaction of AuNPs with the gelator assembly was found to depend critically on the capping ligands protecting the Au surface of the gold nanoparticles. Transmission electron microscopy (TEM) showed a long‐range directional assembly of certain AuNPs along the gel fibers. Scanning electron microscopy (SEM) images of the freeze‐dried gels and nanocomposites indicate that the morphological transformation in the composite microstructures depends significantly on the capping agent of the nanoparticles. Differential scanning calorimetry (DSC) showed that gel formation from sol occurred at a lower temperature upon incorporation of AuNPs having capping ligands that were able to align and noncovalently interact with the gel fibers. Rheological studies indicate that the gel–nanoparticle composites exhibit significantly greater viscoelasticity compared to the native gel alone when the capping ligands are able to interact through interdigitation into the gelator assembly. Thus, it was possible to define a clear relationship between the materials and the molecular‐level properties by means of manipulation of the information inscribed on the NP surface.
Tertiary Amine and N‐Heterocyclic Carbene Coordinated Haloalanes—Synthesis, Structure, and Application
Authors: Alexander Sean G. , Cole Marcus L. , Forsyth Craig M. 
Published: July 2009

AbstractThe preparation of several tertiary amine and N‐heterocyclic carbene coordinated chloro‐ and bromoalanes has been studied and routes to their gram‐scale synthesis optimized. This provides a catalogue of well‐characterized, thermally stable haloalanes for future application. All complexes have been investigated by spectroscopy (IR, NMR) and, where possible, single‐crystal X‐ray diffraction structure determination. A particular focus of this article is the relative thermal stabilities of the complexes, which provides a useful handle for the aerobic stability of Group 13 hydride complexes. These thermal data have been elucidated in full and rationalized relative to one another on the basis of Lewis base donation, steric shielding, and relative inductive halide strengthening of the aluminum hydride bonds by halides. All of the four‐coordinate complexes reported exist as distorted tetrahedra in the solid state with aluminum to N/C‐donor bonds that shorten with the increasing Lewis acidity of the aluminum Lewis acid. The five‐coordinate complexes [AlBrH2(Quin)2] and [AlBr2H(Quin)2] (Quin=quinuclidine) exist in a trigonal‐bipyramidal geometry in the solid state with the amine donors situated in the apical positions. Five chloroalanes; [AlClH2(Quin)], [AlClH2(Quin)2], [AlCl2H(Quin)2], [AlClH2(IMes)], and [AlCl2H(IMes)] (IMes=1,3‐bis(2,4,6‐trimethylphenyl)imidazol‐2‐ylidene), the latter two of which are aerobically stable, have been applied to the hydroalumination of carbonyl and heterocycle substrates and their chemo‐, regio‐, and stereoselectivities compared to those of Group 13 hydride reagents cited in the literature. Overall, the reactivities of these species are comparable to non‐halogenated alane complexes with the additional benefit of aerobic stability, non‐pyrophoricity, and enhanced regioselectivity borne out of greater Lewis acidity.
Highly Effective Recognition of Carbohydrates by Phenanthroline‐Based Receptors: α‐ versus β‐Anomer Binding Preference
Authors: Mazik Monika , Hartmann Andrè , Jones Peter G. 
Published: July 2009

Abstract1H NMR spectroscopic titrations in competitive and non‐competitive media, as well as binding studies in two‐phase systems, such as phase transfer of sugars from aqueous into organic solvents and dissolution of solid carbohydrates in apolar media revealed both highly effective recognition of neutral carbohydrates and interesting binding preferences of an acyclic phenanthroline‐based receptor1. Compared to the previously described acyclic receptors, compound1displays significantly higher binding affinities, the rare capability to extract sugars from water into non‐polar organic solutions and α‐ versus β‐anomer binding preference in the recognition of glycosides, which differs from those observed for other receptor systems. X‐ray crystallographic investigations revealed the presence of water molecules in the binding pocket of1that are engaged in the formation of hydrogen‐bonding motifs similar to those suggested by molecular modelling for the sugar OH groups in the receptor–sugar complexes. The molecular modelling calculations, synthesis, crystal structure and binding properties of1are described and compared with those of the previously described receptors.
Enantioselective Total Synthesis of Brevetoxin A: Unified Strategy for the B, E, G, and J Subunits
Authors: Crimmins Michael T. , Ellis J. Michael , Emmitte Kyle A. , Haile Pamela A. , McDougall Patrick J. , Parrish Jonathan D. , Zuccarello J. Lucas 
Published: July 2009

AbstractBrevetoxin A is a decacyclic ladder toxin that possesses 5‐, 6‐, 7‐, 8‐, and 9‐membered oxacycles, as well as 22 tetrahedral stereocenters. Herein, we describe a unified approach to the B, E, G, and J rings based upon a ring‐closing metathesis strategy from the corresponding dienes. The enolate technologies developed in our laboratory allowed access to the precursor acyclic dienes for the B, E, and G medium‐ring ethers. The strategies developed for the syntheses of these four monocycles ultimately provided multigram quantities of each of the rings, supporting our efforts toward the completion of a convergent synthesis of brevetoxin A.
Unsteady fluid–solid interaction by a kernel‐based particle method
Authors: Ostad H. , Mohammadi S. 
Published: July 2009

AbstractA Lagrangian stabilized particle method is adopted for the simulation of unsteady fluid flow and gas dynamics. The velocity field smoothing technique, which was successfully implemented for reducing zero energy modes and tensile instabilities in solid problems, is used for the stabilization of the fluid phase. In this method a smoothing technique has been applied and the field values in particles are prevented from excessive jumps due to instability. This approach can replace traditional stabilization methods such as the artificial viscosity approach. In this paper, the corrective smoothed particle method has been implemented for solving governing partial differential equations of fluid. Also a modification in basic governing equations is performed on boundary interfaces to conserve mass and energy quantities. The method is implemented and verified in one‐ and two‐dimensional compressible flow problems. Copyright © 2009 John Wiley & Sons, Ltd.
Multipath effects and adaptive transmission in presence of indoor power line background noise
Authors: Tiru Banty , Boruah P. K. 
Published: July 2009

AbstractThe paper studies the background noise characteristics of a typical indoor power line (PL) in India. The noise decreases rapidly with frequency and can be considered as white beyond 5 MHz. The time variation of the background noise at every frequency in the non‐white region is modeled and compared in different environments which include laboratory and factory setups. In all cases, the background noise can be modeled by density functions related to multipath fading i.e. Nakagami‐m, Rayleigh and Rician. Fading is worse than the Rayleigh fading when the PL network has more connected loads and impedance discontinuities. Single frequency noise shows Rician fading when the background noise is narrowband Gaussian. The results are compared with those obtained in other countries in an attempt to check the validity of the model worldwide. A PL channel noise simulator is developed using the density functions to simulate the background noise. A technique is proposed that adapts the carrier frequency according to the channel property at a particular instant. The performance of such a system is tested in a simulated environment and shows that the method enables transmission of signals at very low transmission power compared with that in the AWGN channel. Copyright © 2009 John Wiley & Sons, Ltd.
Daily and developmental modulation of “premotor” activity in the birdsong system
Authors: Day Nancy F. , Kinnischtzke Amanda K. , Adam Murtaza , Nick Teresa A. 
Published: July 2009

AbstractHuman speech and birdsong are shaped during a sensorimotor sensitive period in which auditory feedback guides vocal learning. To study brain activity as song learning occurred, we recorded longitudinally from developing zebra finches during the sensorimotor phase. Learned sequences of vocalizations (motifs) were examined along with contemporaneous neural population activity in the song nucleus HVC, which is necessary for the production of learned song (Nottebohm et al. 1976: J Comp Neurol 165:457–486; Simpson and Vicario 1990: J Neurosci 10:1541–1556). During singing, HVC activity levels increased as the day progressed and decreased after a night of sleep in juveniles and adults. In contrast, the pattern of HVC activity changed on a daily basis only in juveniles: activity bursts became more pronounced during the day. The HVC of adults was significantly burstier than that of juveniles. HVC bursting was relevant to song behavior because the degree of burstiness inversely correlated with the variance of song features in juveniles. The song of juveniles degrades overnight (Deregnaucourt et al. 2005: Nature 433:710–716). Consistent with a relationship between HVC activity and song plasticity (Day et al. 2008: J Neurophys 100:2956–2965), HVC burstiness degraded overnight in young juveniles and the amount of overnight degradation declined with developmental song learning. Nocturnal changes in HVC activity strongly and inversely correlated with the next day's change, suggesting that sleep‐dependent degradation of HVC activity may facilitate or enable subsequent diurnal changes. Collectively, these data show that HVC activity levels exhibit daily cycles in adults and juveniles, whereas HVC burstiness and song stereotypy change daily in juveniles only. In addition, the data indicate that HVC burstiness increases with development and inversely correlates with song variability, which is necessary for trial and error vocal learning. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009
Broad categories for the diagnosis of eating disorders (BCD‐ED): An alternative system for classification
Authors: Walsh B. Timothy , Sysko Robyn 
Published: July 2009

AbstractObjective:Eating Disorder Not Otherwise Specified (EDNOS), a residual category in DSM‐IV, is the most commonly used eating disorder diagnosis in clinical settings. A diagnostic scheme, termed Broad Categories for the Diagnosis of Eating Disorders (BCD‐ED), is proposed to diminish use of the EDNOS category while preserving the existing eating disorder categories. The objective of this review was to examine the advantages and disadvantages of adopting this scheme for DSM‐V.Method:We reviewed published studies to assess the proportion of individuals with DSM‐IV EDNOS that would be reclassified under the BCD‐ED system, support for the hierarchy of the three categories, and the potential risk of “overdiagnosis.”Results:Adopting the BCD‐ED scheme would have both advantages and disadvantages, but would likely substantially reduce the number of individuals who would receive an EDNOS diagnosis.Discussion:BCD‐ED is a potential method of addressing the high frequency of EDNOS, but would be a major change in how eating disorders are categorized. © 2009 American Psychiatric Association. Int J Eat Disord 2009
Clarifying criteria for cognitive signs and symptoms for eating disorders in DSM‐V
Authors: Becker Anne E. , Eddy Kamryn T. , Perloe Alexandra 
Published: July 2009

AbstractObjective:This article reviews literature relevant to challenges in clinical ascertainment of cognitively‐based diagnostic criteria of anorexia nervosa (AN) and bulimia nervosa (BN) to examine whether revision might enhance their clinical utility.Method:We performed a systematic literature search to identify publications relevant to clinical evaluation of cognitive symptoms of AN and BN.Results:The literature supports several reasons that individuals with an eating disorder may not endorse cognitive symptoms, despite their presence. These include limited insight, minimization, or denial, as well as intentional concealment related to perceived stigma, social desirability, or investment in maintaining behavioral symptoms. We also identified reasons that the word “refusal” in AN criterion A may render its application problematic.Discussion:We conclude that specific guidance for ascertainment of cognitive signs for AN and BN in the absence of patient disclosure or endorsement, longitudinal evaluation, and/or collateral data may improve clinical utility of these diagnostic criteria. © 2009 American Psychiatric Association. Int J Eat Disord 2009