bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling and Simulation
Authors: Diston Dominic J. 
Published: December 2010

AbstractModeling and Simulation (or M&S) encompasses a wide range of techniques for building representations of vehicles and systems and using them in order to predict/replicate behavior and performance. This chapter will provide a context for M&S and then summarize some of the mathematical modeling that is associated with air vehicles (covering principles of flight) and synthetic environment (covering the operational space within which vehicles are immersed). The brief discussion of vehicles will focus on the concepts of architecture, energy and force and will summarize the equations of motion. The synthetic environment will be limited to the essential aspects of a geospatial reference model (namely the shape and motion of the Earth), gravitation and atmosphere. Finally, there will be a brief discussion of simulation principles. The overall aim is to show the diversity of the subject matter as it is applied to real engineering.
Human Health Issues Caused by the Aircraft Environment
Authors: Seabridge Allan 
Published: December 2010

AbstractThis chapter considers the potential impact of the aircraft environment from the point of view of the systems engineer. The aircraft, as a system, is designed to be operated by humans and may carry people as occupants. The aircraft imposes upon its inhabitants various physical stimuli that may affect their physiology. The chapter is not intended to be diagnostic or definitive view; it cannot be because aircraft performance and legislation change periodically. The chapter does not include reference to damage to inhabitants as a result of accidents; it is concerned about those phenomena that are “normal” in the day‐to‐day operation of a complex mechanical machine. The chapter is intended as information for systems engineers to use as guidelines or the design of the aircraft as a system, and to ensure that the well‐being of aircrew, cabin crew, and passengers is taken into account to minimize the impact on their health and the aircraft is compliant with contemporary legislation.
Sensitivity Analysis
Authors: Kim Nam H. 
Published: December 2010

AbstractGradient‐based optimization algorithms require functions values and gradients of objective function and constraints. When an optimization problem has many design variables, calculating gradients is the most time‐consuming part in gradient‐based optimization algorithms. Since the gradient is the rate of change of a function with respect to change in design variables, the method of calculating gradients is often called sensitivity analysis. In this chapter, a brief overview of the most popular sensitivity analysis methods are presented: global finite difference method, discrete method, continuum method, and automatic differentiation method. The performance of each sensitivity analysis method is discussed in terms of accuracy, efficiency, and difficulty in implementation. The global finite difference method is the easiest to implement, but is expensive and its accuracy depends on the perturbation size. The discrete and continuum sensitivities are accurate and efficient, but they require a certain level of effort in implementation. The automatic differentiation method is accurate but requires a huge amount of initial effort in implementation. Several numerical examples are provided using analytical and numerical methods of calculating sensitivity information.
Living on the Moon
Authors: Thangavelu Madhu 
Published: December 2010

AbstractHumans have long dreamt of exploring and settling the Moon. The visions of human space activity stemming from the first half of the 20th century culminated in the Apollo program landing two astronauts on the Moon in 1969, and until 1972, 12 astronauts had walked the Moon and performed scientific experiments. In the new millennium, several nations have begun precursory missions, orbiting a new generation of satellites and gleaning new information. Most recently, water has been discovered in the polar regions, setting the stage for lunar development and human settlement. This chapter provides a brief overview of past visions, present projects and technology developments, and some concepts and technologies for future permanent human settlements on our celestial neighbor.
Study of the Piezoelectric Power Generation of ZnO Nanowire Arrays Grown by Different Methods
Authors: Riaz Mohammed , Song Jinhui , Nur Omer , Wang Zhong Lin , Willander Magnus 
Published: December 2010

AbstractThe piezoelectric power generation from ZnO nanowire arrays grown on different substrates using different methods is investigated. ZnO nanowires were grown on n‐SiC and n‐Si substrates using both the high‐temperature vapor liquid solid (VLS) and the low‐temperature aqueous chemical growth (ACG) methods. A conductive atomic force microscope (AFM) is used in contact mode to deflect the ZnO nanowire arrays. No substrate effect was observed but the growth method, crystal quality, density, length, and diameter (aspect ratio) of the nanowires are found to affect the piezoelectric behavior. During the AFM scanning in contact mode without biasing voltage, the ZnO nanowire arrays grown by the VLS method produced higher and larger output voltage signal of 35 mV compared to those grown by the ACG method, which produce smaller output voltage signal of only 5 mV. The finite element (FE) method was used to investigate the output voltage for different aspect ratio of the ZnO nanowires. From the FE results it was found that the output voltage increases as the aspect ratio increases and starts to decreases above an aspect ratio of 80 for ZnO nanowires.
Fabrication of Multiscale Gradient Polymer Patterns by Direct Molding and Spatially Controlled Reflow
Authors: Chae Jae Joon , Lee Sung Hoon , Suh Kahp Y. 
Published: December 2010

AbstractSize variations of pattern spacing as well as gradient control of the as‐formed polymeric pattern via a spatially controlled reflow process are presented. Micro‐ and nanopatterns of polymethyl methacrylate (PMMA) in the form of line‐and‐space strips are first generated by capillary force lithography (CFL), and the residual layers are removed by ashing process. Subsequently, the exposed PMMA strips underwent a controlled reflow process above the glass transition temperature (Tg) while heating single or both sides of the substrate either in parallel to the line pattern (parallel reflow) or perpendicular to the line pattern (perpendicular reflow). As a result of this controlled reflow, a linear or a parabolic profile of pattern spacing is achieved depending on the heating mode. Furthermore, multiscale gradient patterns are formed with the spacing ranging from 98 nm to 4.23 μm (a difference of two orders of magnitude) in a single patterned layer using the original micropattern of 16 μm width and 8 μm spacing. In order to explain reflow behaviors, a simple theoretical model relating the normalized pattern width to the polymer viscosity is derived based on a leveling kinetics of polymer melt. Also, gradient PMMA channels are fabricated and bonded to a glass substrate, which are used to flow a liquid inside the channels by capillarity‐driven flow.
Synthesis and Characterization of New Thieno[3,4‐c]pyrrole‐4,6‐dione Derivatives for Photovoltaic Applications
Authors: Najari Ahmed , Beaupré Serge , Berrouard Philippe , Zou Yingping , Pouliot Jean‐Rémi , Lepage‐Pérusse Charlotte , Leclerc Mario 
Published: December 2010

AbstractA new class of low‐bandgap copolymers based on benzodithiophene (BDT) and thieno[3,4‐c]pyrrole‐4,6‐dione (TPD) units is reported. Chemical modifications of the conjugated backbone promote both high molecular weights and processability while allowing for tuning of the electronic properties. Copolymers with substituted thiophene spacers (alkyl chains facing the BDT unit) or unsubstituted thiophene spacers tend to have low power conversion efficiencies (PCE less than 1%) due to a bad morphology of the active layer, whereas copolymers with substituted thiophene spacers (alkyl chains facing TPD unit) show enhanced morphology and PCEs up to of 3.9%. Finally, BDT‐TPD copolymers without any thiophene spacers still show the best performances with power conversion efficiencies up to 5.2%.
Evaluation of Charge Mobility in Organic Materials: From Localized to Delocalized Descriptions at a First‐Principles Level
Authors: Shuai Zhigang , Wang Linjun , Li Qikai 
Published: December 2010

AbstractThe carrier mobility for carbon electronic materials is an important parameter for optoelectronics. We report here some recently developed theoretical tools to predict the mobility without any free parameters. Carrier scatterings with phonons and traps are the key factors in evaluating the mobility. We consider three major scattering regimes: i) where the molecular internal vibration severely induces charge self‐trapping and, thus, the hopping mechanism dominates; ii) where both intermolecular and intramolecular scatterings come to play roles, so the Holstein‐Peierls polaron model is applied; and, iii) where charge is well delocalized with coherence length comparable with acoustic phonon wavelength, so that a deformation potential approach is more appropriate. We develop computational methods at the first‐principles level for the three different cases that have extensive potential application in rationalizing material design.
Titanium/Palladium‐Mediated Regioselective Propargylation of Ketones using Propargylic Carbonates as Pronucleophiles
Authors: Millán Alba , de Cienfuegos Luis Álvarez , Martín‐Lasanta Ana , Campaña Araceli G. , Cuerva Juan M. 
Published: December 2010

AbstractAn efficient protocol for the synthesis of homopropargylic alcohols using propargylic carbonates as pronucleophiles is reported. The reaction is based on a combination of transition metal (palladium) and radical chemistry (titanium). The reaction takes place with an excellent regioselectivity and tolerates a great degree of substitution of the starting propargylic carbonate, thus being an interesting tool in the context of synthetic organic chemistry.
Lung diffusing capacity relates better to short‐term progression on HRCT abnormalities than spirometry in mild asbestosis
Authors: Nogueira Cristiano Rabelo , Nápolis Lara Maris , Bagatin Ericson , Terra‐Filho Mario , Müller Nestor L. , Silva C. Isabela S. , Rodrigues Reynaldo Tavares , Neder J. Alberto , Nery Luiz E. 
Published: December 2010

AbstractBackgroundPulmonary function tests (PFT), particularly spirometry and lung diffusing capacity for carbon monoxide (DLCO), have been considered useful methods for the detection of the progression of interstitial asbestos abnormalities as indicated by high‐resolution computed tomography (HRCT). However, it is currently unknown which of these two tests correlates best with anatomical changes over time.MethodsIn this study, we contrasted longitudinal changes (3–9 years follow‐up) in PFTs at rest and during exercise with interstitial abnormalities evaluated by HRCT in 63 ex‐workers with mild‐to‐moderate asbestosis.ResultsAt baseline, patients presented with low‐grade asbestosis (Huuskonen classes I–II), and most PFT results were within the limits of normality. In the follow‐up, most subjects had normal spirometry, static lung volumes and arterial blood gases. In contrast, frequency of DLCO abnormalities almost doubled (P < 0.05). Twenty‐three (36.5%) subjects increased the interstitial marks on HRCT. These had significantly larger declines in DLCO compared to patients who remained stable (0.88 vs. 0.31 ml/min/mm Hg/year and 3.5 vs. 1.2%/year, respectively; P < 0.05). In contrast, no between‐group differences were found for the other functional tests, including spirometry (P > 0.05).ConclusionsThese data demonstrate that the functional consequences of progression of HRCT abnormalities in mild‐to‐moderate asbestosis are better reflected by decrements in DLCO than by spirometric changes. These results might have important practical implications for medico‐legal evaluation of this patient population. Am. J. Ind. Med. 54:185–193, 2011. © 2010 Wiley‐Liss, Inc.
“Sarcoid like” granulomatous pulmonary disease in World Trade Center disaster responders
Authors: Crowley Laura E. , Herbert Robin , Moline Jacqueline M. , Wallenstein Sylvan , Shukla Gauri , Schechter Clyde , Skloot Gwen S. , Udasin Iris , Luft Benjamin J. , Harrison Denise , Shapiro Moshe , Wong Karen , Sacks Henry S. , Landrigan Philip J. , Teirstein Alvin S. 
Published: December 2010

AbstractBackgroundMore than 20,000 responders have been examined through the World Trade Center (WTC) Medical Monitoring and Treatment Program since September 11, 2001. Studies on WTC firefighters have shown elevated rates of sarcoidosis. The main objective of this study was to report the incidence of “sarcoid like” granulomatous pulmonary disease in other WTC responders.MethodsCases of sarcoid like granulomatous pulmonary disease were identified by: patient self‐report, physician report and ICD‐9 codes. Each case was evaluated by three pulmonologists using the ACCESS criteria and only “definite” cases are reported.ResultsThirty‐eight patients were classified as “definite” cases. Six‐year incidence was 192/100,000. The peak annual incidence of 54 per 100,000 person‐years occurred between 9/11/2003 and 9/11/2004. Incidence in black responders was nearly double that of white responders. Low FVC was the most common spirometric abnormality.ConclusionsSarcoid like granulomatous pulmonary disease is present among the WTC responders. While the incidence is lower than that reported among firefighters, it is higher than expected. Am. J. Ind. Med. 54:175–184, 2011. © 2010 Wiley‐Liss, Inc.
Synthesis and Anti‐Hepatitis B Virus Activity of a Novel Class of Thiazolylbenzimidazole Derivatives
Authors: Luo Yu , Yao Jia‐Ping , Yang Li , Feng Chun‐Lan , Tang Wei , Wang Gui‐Feng , Zuo Jian‐Pin , Lu Wei 
Published: December 2010

AbstractRecently, heterocyclic benzimidazole derivatives have been investigated and validated as a promising class of antiviral agents. In this paper, a series of novel thiazolylbenzimidazole derivatives was synthesized and evaluated for their anti‐hepatitis B virus (HBV) activity and cytotoxicity on the HepG2.2.15 cell line. Afterwards, the preliminary structure–activity relationship (SAR) was discussed. Compound 8b, with IC50 = 1.1 µM and SI > 90.9, was the most promising compound and could be selected as a benchmark compound for further investigation.
Platinum Complexes with 5‐Methyl‐5(4‐pyridyl)hydantoin and Its 3‐Methyl Derivatives: Synthesis and Cytotoxic Activity – Quantitative Structure‐Activity Relationships
Authors: Bakalova Adriana , Varbanov Hristo , Buyukliev Rossen , Momekov Georgi , Ivanov Darvin , Doytchinova Irini 
Published: December 2010

Abstract3,5‐Dimethyl‐5‐(4‐pyridyl)hydantoin (L) and its platinum(II) and platinum(IV) complexes with the general formula cis‐[PtL2X2] · n H2O and [PtL2Cl4], where XCl, I and n = 2‐4 were synthesized. A new Pt(IV) complex with 5‐methyl‐5‐(4‐pyridyl)hydantoin (L′) with the formula cis‐[Pt(L′)2Cl2(OH)2] · 5 H2O was also synthesized. The novel compounds were characterized by elemental analysis, IR, 1H‐, 13C‐, 195Pt‐NMR spectra and molar conductivity. The cytotoxic effects of these complexes were examined on three human tumor cell lines by MTT‐dye reduction assay. These four new Pt(II) and Pt(IV) complexes and a set of another twelve Pt(II), Pt(IV), and Pd(II) complexes previously synthesized and tested were compiled and a QSAR model was derived in order to direct the further rational synthesis.
Ibuprofen and Glutathione Conjugate as a Potential Therapeutic Agent for Treating Alzheimer's Disease
Authors: Pinnen Francesco , Sozio Piera , Cacciatore Ivana , Cornacchia Catia , Mollica Adriano , Iannitelli Antonio , D′Aurizio Eleonora , Cataldi Amelia , Zara Susi , Nasuti Cinzia , Di Stefano Antonio 
Published: December 2010

AbstractNon‐steroidal anti‐inflammatory drugs (NSAIDs) and antioxidant therapy might protect against the development of Alzheimer's disease (AD). In the present work, we synthesized a molecular combination of glutathione (GSH) and ibuprofen (IBU) via an amide bond and investigated its potential for targeted delivery of the parent drugs to neurons, where cellular oxidative stress and inflammation are related to AD. Evaluation of its physicochemical and in‐vitro antioxidant properties indicated that compound 1 exhibits good stability toward human plasma enzymatic activity, and, like GSH, displays in‐vitro free radical scavenging activity in a time and concentration‐dependent manner. The new compound was also assessed by infusion in a rat model for Alzheimer's disease for its potential to antagonize the deleterious structural and cognitive effects of β‐amyloid(1‐40). In behavioral tests of long‐term spatial memory, animals treated with codrug 1 performed significantly better than those treated with β‐amyloid (Aβ) peptide. Histochemical findings confirmed the behavioral data, revealing that Aβ protein was less expressed in cerebral cortex treated with 1 than that treated with IBU. Taken together, the present findings suggest that conjugate 1 treatment may protect against the oxidative stress generated by reactive oxygen species (ROS) and the cognitive dysfunction induced by intracerebroventricular (i.c.v.) infusion of Aβ(1‐40) in rats, and thus that codrug 1 could prove useful as a tool for controlling AD induced cerebral amyloid deposits and behavioral deterioration.
Design, Synthesis and Structure–Activity Relationship of Functionalized Tetrahydro‐β‐carboline Derivatives as Novel PDE5 Inhibitors
Authors: Ahmed Nermin S. , Gary Bernard D. , Tinsley Hethar N. , Piazza Gary A. , Laufer Stefan , Abadi Ashraf H. 
Published: December 2010

AbstractStarting from tadalafil as a template, a series of functionalized tetrahydro‐β‐carboline derivatives have been prepared and identified as novel potent and selective PDE5 inhibitors. Replacing the 3,4‐methylenedioxyphenyl at position 6 of tadalafil, together with elongation of the N2‐methyl substituent and manipulation of the stereochemical aspects of the two chiral carbons led to the identification of compound XXI, a highly potent PDE5 inhibitor (IC50 = 3 nM). Compound XXI was also highly selective for PDE5 versus PDE3B, PDE4B, and PDE11A, with a selectivity index of 52 and 235 towards PDE5 rather than PDE11 with both cAMP and cGMP as substrate, respectively.
Late‐Stage Diversification of Chiral N‐Heterocyclic‐Carbene Precatalysts for Enantioselective Homoenolate Additions
Authors: Zheng Pinguan , Gondo Chenaimwoyo A. , Bode Jeffrey W. 
Published: December 2010

AbstractA library of chiral triazolium salts has been prepared by late‐state diversification of a triazolium amine salt. By utilizing a primary amine as a functional handle, a single triazolium salt can be transformed into a variety of chiral N‐heterocyclic carbene precatalysts. This approach makes the preparation of chiral N‐heterocyclic carbenes possible by a single‐step modification of a triazolium salt, rather than the usual need for multistep organic synthesis and challenging heterocycle formation for each member of a catalyst library. We have screened these catalysts for control of diastereo‐ and enantioselectivity in a γ‐lactam‐forming reaction between α,β‐unsaturated aldehydes and cyclic ketimines.
Synthesis of Chiral Biphenol‐Based Diphosphonite Ligands and Their Application in Palladium‐Catalyzed Intermolecular Asymmetric Allylic Amination Reactions
Authors: Shi Ce , Chien Chih‐Wei , Ojima Iwao 
Published: December 2010

AbstractA library of new 2,2′‐bis(diphenylphosphinoyloxy)‐1,1′‐binaphthyl (binapo)‐type chiral diphosphonite ligands was designed and synthesized based on chiral 3,3′,5,5′,6,6′‐hexasubstituted biphenols. These bop ligands have exhibited excellent efficiency in a palladium‐catalyzed intermolecular allylic amination reaction, which provides a key intermediate for the total synthesis of Strychnos indole alkaloids with enantiopurities of up to 96 % ee.
Variants in several genomic regions associated with asperger disorder
Authors: Salyakina D. , Ma D.Q. , Jaworski J.M. , Konidari I. , Whitehead P.L. , Henson R. , Martinez D. , Robinson J.L. , Sacharow S. , Wright H.H. , Abramson R.K. , Gilbert J.R. , Cuccaro M.L. , Pericak‐Vance M.A. 
Published: December 2010

AbstractAsperger disorder (ASP) is one of the autism spectrum disorders (ASD) and is differentiated from autism largely on the absence of clinically significant cognitive and language delays. Analysis of a homogenous subset of families with ASP may help to address the corresponding effect of genetic heterogeneity on identifying ASD genetic risk factors. To examine the hypothesis that common variation is important in ASD, we performed a genome‐wide association study (GWAS) in 124 ASP families in a discovery data set and 110 ASP families in a validation data set. We prioritized the top 100 association results from both cohorts by employing a ranking strategy. Novel regions on 5q21.1 (P = 9.7 × 10−7) and 15q22.1–q22.2 (P = 7.3 × 10−6) were our most significant findings in the combined data set. Three chromosomal regions showing association, 3p14.2 (P = 3.6 × 10−6), 3q25–26 (P = 6.0 × 10–5) and 3p23 (P = 3.3 × 10−4) overlapped linkage regions reported in Finnish ASP families, and eight association regions overlapped ASD linkage areas. Our findings suggest that ASP shares both ASD‐related genetic risk factors, as well as has genetic risk factors unique to the ASP phenotype.
Molecular Recognition of β‐O‐GlcNAc Glycopeptides by a Lectin‐Like Receptor: Binding Modulation by the Underlying Ser or Thr Amino Acids
Authors: Corzana Francisco , Fernández‐Tejada Alberto , Busto Jesús H. , Joshi Gururaj , Davis Anthony P. , Jiménez‐Barbero Jesús , Avenoza Alberto , Peregrina Jesús M. 
Published: December 2010

AbstractThe binding properties of different carbohydrates and glycopeptides containing the β‐O‐2‐deoxy‐2‐(N‐acetyl)‐D‐glucosaminyl (β‐O‐GlcNAc) to a synthetically prepared lectin‐like receptor have been analyzed. The study combines the use of NMR spectroscopy experiments with extensive MD simulations in explicit water. Notably, the presence of a key hydrogen bond between the receptor and the OMe group of the β‐O‐GlcNAc‐OMe derivative appears to be responsible for the high selectivity observed for this compound. In addition, to study the effect on the binding of the underlying amino acid, we have prepared different model glycopeptides, which include the non‐natural α‐methylserine and α‐methylthreonine as underlying amino acids. Interestingly, the presence of a methyl group decreases the affinity constant, especially in those cases in which a β‐methyl group is present. As a result, the serine‐containing glycopeptide exhibited the highest affinity constant of the glycopeptides, and the threonine derivative showed the lowest one. This low selectivity could have its origin in the difficulty to form both specific hydrogen bonds and hydrophobic (CH‐π) contacts.
A Novel Synthesis Route for Cu/ZnO/Al2O3 Catalysts used in Methanol Synthesis: Combining Continuous Consecutive Precipitation with Continuous Aging of the Precipitate
Authors: Kaluza Stefan , Behrens Malte , Schiefenhövel Nora , Kniep Benjamin , Fischer Richard , Schlögl Robert , Muhler Martin 
Published: December 2010

AbstractA novel continuous method for the preparation of a ternary Cu/ZnO/Al2O3 catalyst based on a cascade of micromixers and a tubular aging reactor is presented as a promising alternative route to the conventional batch process. Its application, in combination with immediate spray drying, enables monitoring of the formation of the final precursor by exchange reactions between initially separated phases during the aging step. These exchange reactions were successfully simulated by consecutive precipitation by using micromixers in series as analytical tool. After 60 min of continuous aging, calcination, and reduction, a catalyst is produced that exhibits an almost equal mass‐related activity in methanol synthesis compared to a commercial catalyst and an area‐related activity that is about 50 % higher.