bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimum design of perforated plug mufflers using a neural network and a genetic algorithm
Authors: Chang Y-C , Chiu M-C , Cheng M-M 
Published: December 2008

Research on new techniques of perforated plug silencers has been well addressed. Most researchers have explored noise reduction effects based on a pure plane wave theory. However, the maximum noise reduction of a silencer under a space constraint, which frequently occurs in engineering problems, is rarely addressed. Therefore, the optimum design of mufflers becomes an essential issue. In this paper, to save the design time during the flexible optimum process, a simplified mathematical model of a muffler is constructed with a neural network with a series of real data — input design data (muffle dimensions) and output data (theoretical sound transmission loss (STL)) were approximated by a theoretical mathematical model (TMM) in advance. To assess the optimal mufflers, the neural network model (NNM) is used as an objective function in conjunction with a genetic algorithm (GA). Moreover, the numerical cases of sound elimination with respect to various parameter sets and pure tones (500, 1000, and 2000 Hz) are exemplified and discussed. Before the GA operation is carried out, the approximation between TMM and real data is checked. In addition, both the TMM and NNM are compared. It is found that the TMM and the experimental data are in agreement. Moreover, the TMM and NNM conform. Optimal results reveal that the maximum amount of the STL can be optimally obtained at the desired frequencies. Consequently, the optimum algorithm proposed in this study can provide an efficient method to develop optimal silencers in industry.
Hardware versus lumped cross-monitoring in smart multilane torque-summed electromechanical actuators
Authors: Annaz F Y 
Published: December 2008

High integrity in multilane smart electromechanical actuation systems is achieved through hardware redundancy and intelligent monitoring. Hardware redundancy is associated with the inclusion of repeated hardware of key components that are likely to fail. Intelligent monitoring is associated with the inclusion of a fault detection and fault isolation (FDI) system that is capable of correctly detecting, identifying, isolating, and replacing failed components. The main aim of this paper is to address two cross-monitoring techniques (lumped and three-phase) in a single-type torque-summed architecture. In the lumped cross-monitoring technique, all lanes will be represented by their lumped models, while in hardware cross-monitoring, three-phase equivalents will model each motor. The latter is a more accurate representation and allows for more detailed motor and power conditioner failure-related tests. The analysis is based on a four-lane actuation system capable of driving aerodynamic and inertial loads (with two lanes failed) of an aileron control surface similar to that of the Sea Harrier. The paper will start by giving an overview of the system, by describing: The paper will then proceed to develop a threshold setting strategy by examining peak lane disparities due to inherent system randomness. The largest failure transient envelopes after failure isolations are then identified for different flight conditions, and their impact on the aircraft response in roll will then be assessed. The paper will conclude by showing that both actuator and aircraft requirements were met despite the use of two different cross-monitoring techniques.
Metal-Catalyzed Reactions of Organoboronic Acids and Esters
Authors: Miyaura Norio 
Published: December 2008

Abstract
Metal-catalyzed B–C and C–C bond-forming reactions of organoboronic acids that have been pursued in the past three decades by our group are summarized in this article. B–C bond-forming reactions for the synthesis of organoboronic acid derivatives include metal-catalyzed addition reactions of pinacolborane or catecholborane (hydroboration), bis(pinacolato)diboron (diboration), and alkylthioboranes (thioboration) to alkenes, alkynes, 1,3-alkadienes, or 1,2-alkadienes (allenes). Other B–C bond-forming reactions include coupling reactions of pinacolborane or bis(pinacolato)diboron for borylation of C–halogen bonds with palladium catalysts and C–H bonds of arenes and alkenes with iridium catalysts. These reactions have provided a convenient new access to aryl-, 1-alkenyl-, allyl-, or benzylboronates. Metal-catalyzed C–C and C–N bond-forming reactions using boronic acid derivatives include synthesis of novel cyclic triolborate salts for palladium- or copper-catalyzed cross-coupling reactions with organic halides or amines, rhodium- or palladium-catalyzed 1,4-addition reactions of arylboronic acids to α,β-unsaturated carbonyl compounds and rhodium-catalyzed addition of aryl- and 1-alkenylboronic acids to aldehydes and imines.
Molecular Self-Assembly into One-Dimensional Nanotube Architectures and Exploitation of Their Functions
Authors: Shimizu Toshimi 
Published: December 2008

Abstract
This review article focuses on the self-assembly of amphiphilic molecules into discrete, hollow cylindrical tubular architectures (organic nanotubes). Research on nanotube formation from dumbbell-shaped peptide lipids, 1-O-glucopyranoside and 1-N-glucopyranosylamide lipids, and wedge-shaped bolaamphiphilic glycolipids with carboxylic, amino, or oligoglycine groups at one end has been outlined with their characteristic self-assembly. Finally, recent progress in mass production, dimension control, and novel functions of organic nanotubes are described.
Specific Fragmentation of K-Shell Excited/Ionized Pyridine Derivatives Studied by Electron Impact: 2-Amino-3-methylpyridine and 3-Methylpyridine
Authors: Okada Kazumasa , Sakai Masamichi , Ohno Keiichi 
Published: December 2008

Abstract
Fragmentation of 2-amino-3-methylpyridine has been investigated by electron impact in the carbon and nitrogen K-shell excitation regions with a comparison to that of 3-methylpyridine. Fragment ions were analyzed with a quadrupole mass spectrometer. Yields of the NCNH2+ and C5H3+/C4HN+ fragment ions characteristically increase at the N 1s edge when compared to the C 1s excitation/ionization and valence ionization. This observation indicates that a valence electron forming the C–N bond in the pyridine ring is preferentially released through an Auger electron emission at the N 1s edge. The fragment ions produced via a hydrogen atom shift were observed as well.
High Efficiencies for Singlet Oxygen Generation of Fullerenes and Their Phototoxicity
Authors: Iizumi Yoko , Okazaki Toshiya , Zhang Minfang , Yudasaka Masako , Iijima Sumio 
Published: December 2008

Abstract
Although fullerenes have been known as strong photosensitizers (PS), the quantitative evaluations of their activities have been insufficient, especially in water. We measured the near-infrared (NIR) emission from the singlet oxygen (1O2) produced by C60 and C70 dissolved in water using dispersants of γ-cyclodextrin (γ-CD) or poly(vinylpyrrolidone) (PVP), and estimated the 1O2 generation efficiencies. The obtained results show that C60 and C70 can generate 1O2 with 2–3 times higher efficiencies than the well-known PS, rose bengal (RB), and the 1O2 generation efficiencies depends on the dispersants. Phototoxicity of C60 and C70 were also examined by using rat fibroblast cell line (5RP7). The cell viabilities after irradiations were consistent with the corresponding 1O2 generation efficiencies. Our results that fullerenes have high 1O2 generation efficiencies assure the potential applications of fullerenes as PS for photodynamic therapy (PDT).
Transformation of a Modest Luminescent Chemosensor into a Light-Up Probe: The Overload Displacement Approach
Authors: Schmittel Michael , Lin Hengwei 
Published: December 2008

Abstract
As a proof of principle for the overload displacement strategy a luminescent ruthenium(II) azacrown ether phenanthroline with restrained sensoric properties has been converted into a light-up chemosensor for lead(II) ions by overloading the system with copper(II) ions.
An Efficient Identification Method of a Specific Binding Protein for a Bioactive Compound Using On-Bead Digestion and Mass Spectrometry
Authors: Sakai Mitsuru , Furuya Minoru , Endo Hiroko , Yamaoka Kazuyoshi , Kondo Shiro , Koike Tohru 
Published: December 2008

Abstract
Affinity chromatography is widely utilized as a tool in biomedical research and biotechnology. This purification method provides increased sensitivity for various kinds of analyses, such as mass spectrometry. This report describes a protocol to identify a specific binding protein for a bioactive compound (BAC) using BAC-affinity beads and nanoflow liquid chromatography tandem mass spectrometry (nano-LC/MS/MS). After the target protein was digested directly on the affinity beads, the obtained peptide fragments were determined by MS analysis. The binding-specificity was shown by a competition experiment using beads lacking bound BAC. In this study, we describe two examples for benzenesulfonamide- and methotrexate-binding proteins.
Anti-Inflammatory Polyoxygenated Steroids from the Soft Coral Sinularia sp.
Authors: Su Jui-Hsin , Lo Ching-Li , Lu Yi , Wen Zhi-Hong , Huang Chiung-Yao , Dai Chang-Feng , Sheu Jyh-Horng 
Published: December 2008

Abstract
Four new polyhydroxylated steroids (1–4) were isolated from a Formosan soft coral Sinularia sp. The structures of these metabolites were determined on the basis of spectroscopic (IR, MS, and 1D and 2D NMR) analyses. Among these metabolites, 3 and 4 are rarely found marine steroids with a C-9/C-10 double bond. Compounds 1 and 2 have shown significant inhibition of the accumulation of the pro-inflammatory COX-2 protein of LPS-stimulated RAW264.7 macrophage cells at 10 μM.
1- and 3-Nitreno-2-naphthylcarbenes. A Combined Experimental and Computational Study
Authors: Tomioka Hideo , Nakane Norio , Tatsugi Jiro 
Published: December 2008

Abstract
The structures, energies, and thermal stabilities of E and Z isomers of a singlet, a triplet, and a quintet states of naphthalene bearing nitrene and carbene units on adjacent (1,2- and 3,2-) positions were examined by DFT methods. For both 1,2- and 3,2-isomers, singlet quinoidal diradicals were predicted to be the ground state with the corresponding triplet state lying slightly higher in energy. The quintet state of the 1,2-isomer was found to lie approximately 30 kcal mol−1 (1 kcal = 4.184 kJ) above the ground state, while that of the 3,2-isomer was predicted to lie only 9 kcal mol−1 above the ground state. This difference is discussed in terms of loss of energy due to aromaticity between the two isomers. Thermal stability of the ground state in terms of ring-opening and -closure reactions indicated that both isomers prefer to decay by the latter process forming naphtho[b]azetes. Attempts to generate and characterize the ground state quionoidal diradical by matrix IR spectroscopic methods in Ar at low temperature all resulted in the detection of the azete.
New Polyoxygenated Briaranes from Octocorals Briareum excavatum and Ellisella robusta
Authors: Hwang Tsong-Long , Lin Mei-Ru , Tsai Wei-Tse , Yeh Hsiao-Chien , Hu Wan-Ping , Sheu Jyh-Horng , Sung Ping-Jyun 
Published: December 2008

Abstract
Six new polyoxygenated briarane-type diterpenoids, briaexcavatins Q–T (1–4) and robustolides J (5) and K (6), were isolated from a cultured octocoral Briareum excavatum and a sea whip gorgonian coral Ellisella robusta, respectively. The structures of briaranes 1–6 were established by spectroscopic methods. Briarane 3 exhibited weak cytotoxicity toward CCRF-CEM tumor cells and briaranes 5 and 6 displayed inhibitory effects on superoxide anion generation by human neutrophils.
Effect of Bulk Natural Convection on Chemical Processes Studied in a Tight Polymer Gel Reactor Composed of Polysaccharide Network and a Large Excess of Water
Authors: Ueno Hirohito , Gokan Norihiko , Nakano Yoshiharu , Kaneko Masao 
Published: December 2008

Abstract
The effect of bulk natural convection on various chemical processes was investigated in a tight polysaccharide gel reactor composed of a few percent polysaccharide and excess water. It was elucidated that molecular self-diffusion coefficient (D cm2 s−1) in the gel is the same as in liquid water, but bulk natural convection is entirely prohibited making the molecular transport in these gels remarkably slower than in liquid water. Three-dimensional (3D) diffusion of Ru(bpy)32+ in a tight 0.125 wt % agarose gel took place only by molecular self-diffusion since bulk natural convection is prohibited, and the diffusion length agreed well with the theoretical 3-dimensional (3-D) self-diffusion length calculated from D. 2D diffusion of thionine in a polysaccharide gel also agreed well with the theoretical 2-D self-diffusion length showing also the absence of bulk natural convection. The chemical processes in the tight gel reactor in relevance to natural convection effects are discussed in terms of the time scale of the chemical process and the corresponding self-diffusion length of the reactants. For short time scale processes (ns to s) such as photochemical and electrochemical reactions, the process was not affected by bulk natural convection, but for a longer time scale (0.1 to 10 h) the effect of bulk natural convection was large.
Fabrication of Conjugated Polymer Hybrid Thin Films with Radially Oriented Aluminosilicate Nanofibers by Spin-Assembly
Authors: Jiravanichanun Nattha , Yamamoto Kazuya , Yonemura Hiroaki , Yamada Sunao , Otsuka Hideyuki , Takahara Atsushi 
Published: December 2008

Abstract
Multilayer hybrid films of imogolite nanofibers and water-soluble poly(p-phenylene) (WS-PPP) were prepared by two assembly methods. Layer-by-layer (LBL) assembly and spin-assembly were applied to fabricate the hybrid films. The deposited amount of WS-PPP per thickness was not significantly different between the two methods. However, the spin-assembly method gave significant orientation of imogolite nanofibers aligned in the radial direction, while imogolite nanofibers were randomly networked in the LBL film. The results suggested that lyotropic mesophase of imogolite and centrifugal and shear forces influenced a self-assembly of imogolite fibers oriented in a force-inducing direction.
Students' conceptions of constructivist learning in different programme years and different learning environments
Authors: Loyens Sofie M. M. , Rikers Remy M. J. P. , Schmidt Henk G. 
Published: December 2008

Background Constructivist views of learning have brought conceptions of learning to attention again. Conceptions are considered important determinants of effective learning. Students can differ in their conceptions depending on their educational experience.Aims The present study investigated students' conceptions of constructivist learning. Do students with greater experience in their academic programme differ in their conceptions of constructivist learning compared to students with less experience/ In addition, to what extent are conceptions of constructivist learning different in a conventional, lecture‐based curriculum compared to a constructivist, problem‐based learning curriculum/SamplesThree groups (i.e. first‐year, second‐year, and third‐year students) in two different curricula (i.e. conventional, lecture‐based and constructivist, problem‐based) were tested.Methods A cross‐sectional design was used. Students' conceptions of constructivist activities (i.e. knowledge construction, cooperative learning, self‐regulation, use of authentic problems, self‐perceived inability to learn, and motivation to learn) were measured by a questionnaire. Data were analyzed using a two‐way multivariate analysis of variance (MANOVA).Results A significant difference in questionnaire's scores between year 1 and year 2 (but not between year 2 and 3) was found with respect to conceptions about knowledge construction, self‐regulation, and the use of authentic problems, but not for cooperative learning and motivation to learn. For self‐perceived inability, an interaction effect was found. Furthermore, results showed significant differences between both curriculum groups on all dependent measures.Conclusions Differences in conceptions can be perceived between students who enter a new learning programme (i.e. higher education) and students who already have one year of experience in higher education. Among students with more than one year of educational experience, differences disappear. Furthermore, this study shows that the learning environment can make a difference with respect to students' conceptions of constructivist learning activities.
Temperature as a toxicity identification evaluation tool for pyrethroid insecticides: Toxicokinetic confirmation
Authors: Harwood Amanda D. , You Jing , Lydy Michael J. 
Published: December 2008

AbstractToxicity identification evaluation (TIE) methods can be used to identify toxic compounds in environmental samples using a variety of laboratory techniques. Whereas TIEs exist for nonpolar organics, relatively few methods are established for individual contaminant classes. Toxicity identification evaluations have shown pesticides to be the cause of toxicity in agricultural waters and effluents, and more recent studies have shown that the insecticide class of concern is pyrethroids. The primary objectives of the present study were to confirm a temperature TIE model and mechanistically explain these trends. This was achieved by comparing the relative toxicity and influence of temperature (13 vs 23°C) on Chironomus dilutus exposed to four insecticides, including two pyrethroids, an organophosphate, and an organochlorine, and then explaining these changes using toxicokinetics. A 10°C temperature decrease increased the toxicity of pyrethroids and DDT but decreased the toxicity of chlorpyrifos. The decrease in chlorpyrifos toxicity was driven primarily by the reduction of the formation of more toxic products via decreased biotransformation. The increase in DDT toxicity, in contrast, can be attributed to increased nerve sensitivity at 13 versus 23°C. The pyrethroid toxicity change, however, resulted from a combination of increased accumulation of parent compound and increased nerve sensitivity, exacerbating the toxicity of pyrethroids at 13°C. These trends also held true in sediment exposures with chlorpyrifos and permethrin, indicating that water-only exposures were adequate substitutes for examining this mechanism.
Modeling of biofilm in the water distribution system
Authors: Hu Tai-Lee , Lin Chenfang , Chen Wei-Yu 
Published: December 2008

In order to understand the growth of biofilm and to serve as the basis of cleaning the water distribution pipeline, this study used a multi-attachment dynamic model to simulate the growth of microorganisms' attachment to the pipe wall. The model had considered attachment, detachment, and propagating factors. The attachment and detachment factors are divided into “cell to cell” and “cell to substratum”. Factors for biofilm growth included two possibilities, which was “lateral growth” and “vertical growth”. Data set of the biofilm biomass from a laboratory scale water distribution system was measured. The data and the model simulation curves were compared so as to justify the performance of the model.
The results show that several sets of parameters could be identified. From the simulation of biofilm biomass in the pipeline, the microbial growth related with the incubation time. Due to nutrients being restricted, the biomass of biofilm in the water distribution system did not continue to grow and reached a maximum at about Day 40. From the simulation results, it was suggested the time of cleaning the water distribution pipeline be shortened to one or two months.
The model was applied to simulate the tap water biofilm in the pipeline of Kaohsiung city, the second largest in Taiwan with 1.5 million population. The results revealed various levels of risks and the proportionality between the biomass in the water and the growth rate of biofilm. However, most households had the purifying facility of a reverse osmosis system. From the simulation, the facility proved its effectiveness for preventing the intervention of bacteria from the biofilm formation in the distribution pipelines.
Endoscopic cystoventriculostomy for treatment of paraxial arachnoid cysts
Authors: Oertel Joachim M. K. , Baldauf Jörg , Schroeder Henry W. S. , Gaab Michael R. 
Published: December 2008

Object
The optimal therapy of arachnoid cysts is controversial. In symptomatic extraventricular arachnoid cysts, fenestration into the basal cisterns is the gold standard. If this is not feasible, shunt placement is frequently performed although another endoscopic option is available.

Methods
Between March 1997 and June 2006, 12 endoscopic cystoventriculostomies were performed for the treatment of arachnoid cysts in 11 patients (4 male and 7 female patients, mean age 52 years [range 14–71 years]). All patients were prospectively followed up.

Results
In 11 cases, the arachnoid cysts were frontotemporoparietal and fenestration was performed into the lateral ventricle. In 1 case, the arachnoid cyst was located in the cerebellum and the cyst was fenestrated into the fourth ventricle. Neuronavigational guidance was used in all but 1 case. Endoscopic cystoventriculostomy was performed in all cases without complications. No stents were placed. The mean surgical time was 71 minutes (range 30–110 minutes). The mean follow-up period was 42.7 months (range 19–96 months) per surgical case and 48.8 months (range 19–127 months) per patient. Symptoms improved after 11 of the 12 procedures; 7 of the 11 patients became symptom-free and the others had only mild residual symptoms. The patient who did not experience clinical improvement suffered from depression and demonstrated a significant decrease of the cyst size on the postoperative MR imaging. After 11 of 12 procedures, a decrease in cyst size was observed. In 1 case, a subdural hematoma developed; it required surgical treatment 3 months after surgery. In another case, reclosure of the stoma required repeated endoscopic cystoventriculostomy more than 7 years after the initial procedure.

Conclusions
Overall, endoscopic cystoventriculostomy represents a useful treatment option for patients with paraxial arachnoid cysts in whom a standard cystocisternotomy is not feasible. Based on the results in this case series, stent placement appears not to be required. Despite the long mean follow-up of almost 4 years, however, a longer follow-up period seems to be required before definite conclusions can be drawn.