bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of acetylenic ketones by a Pd-catalyzed carbonylative three-component coupling reaction in [bmim]PF6
Authors: Fukuyama Takahide , Yamaura Ryo , Ryu Ilhyong
Published: September 2005

A carbonylative three-component coupling reaction of aryl iodides with terminal alkynes catalyzed by PdCl2(PPh3)2 was carried out using an ionic liquid, [bmim]PF6, as the reaction medium, which resulted in good yields of α,β-acetylenic ketones. The low-viscosity ionic liquid, [bmim]NTf2, was not suitable for this reaction, since the background Sonogashira coupling reaction, a competing reaction, also proceeded.Key words: carbonylation, palladium, three-component coupling, ionic liquid, α,β-acetylenic ketones.
Oppenauer-type oxidation of secondary alcohols catalyzed by homogeneous water-soluble complexes
Authors: Ajjou Abdelaziz Nait , Pinet Jean-Louis
Published: September 2005

The catalytic system composed of [Ir(COD)Cl]2, 2,2′-biquinoline-4,4′-dicarboxylic acid dipotassium salt (BQC), and sodium carbonate is highly efficient for the selective oxidation of benzylic, 1-heteroaromatic, aliphatic, and allylic secondary alcohols using catalyst:substrate ratios ranging from 0.4% to 2.5%. Sterically hindered allylic alcohols undergo selectively good conversions to the corresponding enones, while unhindered ones are completely isomerized to saturated ketones. Mercury tests indicate that the catalytic process is likely homogeneous. The mechanism proposed for this Oppenauer-type oxidation including the isomerization process is based on iridium-alkoxide species.Key words: Oppenauer oxidation, water, catalysis, isomerization, secondary alcohols.
Electron-rich siloxaneplatinum complexes  Synthesis, structures, and reactivity
Authors: Goikhman Roman , Karakuz Tanya , Shimon Linda JW , Leitus Gregory , Milstein David
Published: September 2005

New platinasiloxanes were synthesized and their reactivity was studied. Oxidative addition of (HSiMe2)2O to Pt(PEt3)3 led to dehydrogenation and quantitative formation of the four-membered platinacyclosiloxane [(PEt3)2Pt((SiMe2)2O)] which was characterized by X-ray diffraction. This complex was stable towards non-polar substrates and aerobic conditions, but reacted readily with electrophiles and Lewis acids. Reaction with MeI resulted in ring opening, while MeOTf gave an oxonium complex, with retention of the platinacycle structure. A complex resulting from BF3 coordination to the ring oxygen atom was also obtained. An unprecedented open-chain diplatinasiloxane containing the PtSiOSiOSiPt fragment was formed by oxidative addition of HSiMe2OSiMe2OSiMe2H to Pt(PEt3)3 and it was characterized by X-ray diffraction.Key words: cyclosiloxane, metallacycle, platinum silyl, Lewis base, oxidative addition.
Studies towards the total synthesis of ouabagenin
Authors: Chen Ling , Deslongchamps Pierre
Published: September 2005

An anionic cyclization strategy developed in our laboratory was used to produce a versatile and convergent synthesis of an advanced tetracyclic intermediate for the construction of ouabagenin and closely related analogs.Key words: organic chemistry, synthesis, cycloaddition, polycyclization, Michael reaction, DielsAlder reaction, steroids, oubain, ouabagenin, natural products.
Competing DielsAlder intramolecular pathways from cross-conjugated trienes: Fused hydrindenones (bicyclo[4.3.0]nonenones) vs. bridged-ring (bicyclo[3.3.1]nonenones) adducts from a diene-transmissive precursor
Authors: Clay Matthew D , Riber Ditte , Fallis Alex G
Published: September 2005

D-Isoascorbic acid was converted to the tetraenone 12 to examine its behaviour in the intramolecular DielsAlder reaction with pendant dienes in a diene-transmissive environment. These studies were directed toward the synthesis of the hydrindenone nucleus via a tether-controlled DielsAlder reaction. It was anticipated that this would lead to a diene-transmissive strategy for steroids such as Desogestrel®. In contrast to our previous studies with decalins, the dominant isomer (150 °C) was the bicyclo[3.3.1]nonadieneone adduct 23, and none of fused adduct 27 was detected. These products were accompanied by two minor hydrindenone adducts 24 and 25. The isomer ratio was dependent on the temperature of the reaction.Key words: DielsAlder, hydrindane, pentadienylation, intramolecular cycloaddition, bicyclo[3.3.1]nonenone.
Synthesis and characterization of novel polysiloxane-grafted fluoropolymers
Authors: Baradie Bilal , Lai Patricia HM , Shoichet Molly S
Published: September 2005

Fluorosilicone polymers combine the properties of both fluorocarbons and siloxanes, yielding materials with unique properties. Novel crosslinked fluorosilicone polymers were synthesized by grafting diisocyanate-terminated polydimethylsiloxane (PDMS) to hydroxyl-functionalized fluoropolymers of poly(tetrafluoroethylene-co-vinyl acetate-co-vinyl alcohol) (PTFE-VAc-VA), as confirmed by elemental bulk and surface analysis. The fluorosilicone polymers containing 34 mol% of TFE were thermally stable with a degradation temperature of 267 °C. Fluorosilicone films were found to be more hydrophobic than the parent, non-grafted fluoropolymers; dynamic advancing and receding water contact angles for PTFE-co-VAc-co-VA-g-PDMS were 104° ± 1° and 61° ± 1°, respectively, whereas for PTFE-co-VAc they were 90° ± 2° and 59° ± 2°. The combined properties of thermal stability and hydrophobicity suggest that these fluorosilicones may be useful for coating and paint applications.Key words: fluoropolymers, fluorosilicone, polydimethylsiloxane, supercritical carbon dioxide.
A MAS NMR and DRIFT study of the Ga species in Ga/H-ZSM5 catalysts and their effect on propane ammoxidation
Authors: Pal Prem , Quartararo Juliette , Abd Hamid Sharifah B , Derouane Eric G , Védrine Jacques C , Magusin Pieter CMM , Anderson Bruce G
Published: September 2005

71Ga, 27Al, and 29Si MAS NMR and DRIFT spectroscopies were used to characterize the state of gallium in Ga/H-ZSM5 catalysts tested for their ability to catalyse the ammoxidation of propane. Ga species were observed in two different possible environments: octahedrally coordinated gallium in small Ga2O3 particles at the external surface of the zeolite crystals, octahedrally coordinated gallium in GaO(OH) or related species, and tetrahedrally coordinated gallium in cationic-exchange positions inside the zeolite. Redox (H2O2) cycles promote the migration of gallium from the GaO(OH) or Ga2O3 species at the external surface of the zeolite crystals to cationic-exchange sites within the zeolite channels. The redox treatment definitely had a beneficial effect on its catalytic performance for the ammoxidation of propane, which is known to occur via a bifunctional mechanism. The main product was acetonitrile at high Ga and Al contents while acrylonitrile was also observed as a side product at high Ga and low Al contents.Key words: ZSM5, MFI, in situ studies, MAS NMR, DRIFT, propane activation, ammoxidation.
Catalytic asymmetric synthesis of cyclopropylphosphonates  Catalysts' scope and reactivity
Authors: Charette André B , Bouchard Jean-Emmanuel
Published: September 2005

The transition metal-catalyzed cyclopropanation of alkenes using α-diazomethylphosphonates leads to cyclopropylphosphonate derivatives in high yields. The reaction proceeds well with copper, rhodium, and ruthenium catalysts. The best catalysts for the enantioselective version are either Evans' Cu·bis(oxazoline) or Nishiyama's Ru·pybox.Key words: cyclopropylphosphonic acids, copper catalysts, ruthenium catalysts, cyclopropanation, diazo reagents.
Palladium-catalyzed asymmetric cyclocarbonylation of allyl naphthols
Authors: Vasapollo Giuseppe , Mele Giuseppe
Published: September 2005

The asymmetric cyclocarbonylation reaction of allyl naphthol catalyzed by palladium complexes and chiral phosphine is reported. The reaction was performed under syn-gas conditions at relatively mild experimental conditions (80100 °C, 300600 psi (1 psi = 6.895 kPa)) in CH2Cl2 as the solvent.Key words: enantioselective, carbonylation, cyclocarbonylation, lactones, palladium acetate.
Thermally accelerated asymmetric hydrosilylations using ligated copper hydride
Authors: Lipshutz Bruce H , Frieman Bryan A , Unger John B , Nihan Danielle M
Published: September 2005

Exposure of a variety of prochiral substrates to [(R)-()-DTBM-SEGPHOS]CuH + PMHS under microwave or conventionally heated conditions reduces reaction times for these hydrosilylations from hours to minutes without significant erosion in ee in most cases.Key words: asymmetric hydrosilylation, copper hydride, microwave irradiation.
Rh(I)-catalyzed cleavage of unactivated CO bonds  Carbonylative rearrangement reactions of allenyl ethers to 2-carboalkoxy-1,3-dienes
Authors: Wender Paul A , Deschamps Nicole M , Sun Robert
Published: September 2005

The initial examples of a Rh(I)-catalyzed carbonylative rearrangement reaction of allenyl ethers are described. The key reaction proceeds under remarkably mild conditions to provide good to excellent yields of 2-carboalkoxy-1,3-dienes.Key words: carbonylative rearrangement, C-O cleavage, σ bond activation, rhodium catalysis, allenyl ethers.
Preparation, characterization, and structure of two dipyrrolide thorium homoleptic complexes  Isolation of a dipyrrolide dipotassium salt with an inverted-sandwich type of structure
Authors: Athimoolam Arunachalampillai , Gambarotta Sandro , Korobkov Ilia
Published: September 2005

Reactions of the in-situ-generated potassium salts of the dipyrroles (C4H3NH)2C(CH3)2 and of (C4H3NH)2C(CH3)(C6H5) with ThCl4(DME)2 has afforded the corresponding homoleptic ({[(C4H3N)2C(CH3)2]3Th}[K2(DME)])n (1) and {[(C4H3N)2C(CH3)(C6H5)]3Th}[K2(DME)] (2). In the case of 1, the solid state polymeric structure was elucidated by X-ray diffraction analysis. Preliminary attempts to reduce these species have so far afforded only intractable materials. Just in the case of 2, it was possible to isolate the corresponding ligand dipotassium salt {(C4H3NH)2C(CH3)(C6H5)[K(DME)]2}n (3) as the only characterizable material. This species possesses an unprecedented inversed-sandwich type of structure. Key words: thorium, homoleptic, dipyrrolide.
Use of fluorescent probes to determine catalytic chain length in chemically amplified resists
Authors: Frenette Mathieu , Ivan Marius Gabriel , Scaiano J C
Published: September 2005

Acid-catalyzed deprotection of tert-butoxycarbonyl (t-Boc) pendant groups present in a polymer film is one of the most common chemical reactions in photolithography. We present here a novel method to determine the catalytic chain length of this reaction under different development conditions. We demonstrate this in model PMMA thin films containing triphenylsulphonium triflate as a photoacid generator, acid sensor coumarin 6, t-Boc protected coumarin 4, and base 2-piperidin-1-yl-ethanol (2-PE). Deprotection of the t-Boc group, catalyzed by the photogenerated acid, during the post-exposure bake leads to formation of coumarin 4, a strongly fluorescent molecule whose concentration is monitored using fluorescence. We take advantage of the change in the emission spectra of coumarin 6 upon protonation to monitor acid formation. To quantify the amount of acid, an acidbase titration is done in the polymer film using 2-PE. Knowing the amount of deprotected probe and the amount of acid, we are able to calculate the number of moles of deprotected C4-t-Boc per mol of acid, which is the actual catalytic chain length.Key words: photolithography, chemical amplification, catalytic chain length, fluorescent sensors, photoacid generator.
Design and synthesis of oxazolidinone ketolide antibiotic segment mimetics
Authors: Hanessian Stephen , Kothakonda Kiran Kumar
Published: September 2005

Macrolides have been modified to a large extent by structural and functional variants to expand their spectrum of activity and overcome resistance. Ketolides are new generation 14-membered ring macrolides derived by chemical modification of the readily available erythromycin A. We have designed and synthesized bicyclic oxazolidinone-δ-lactones to mimic the "left segment" periphery of ketolides.Key words: macrolide, ketolide, 50S r-RNA, segment mimetics.
Direct synthesis of unprotected α-amino acids via allylation of hydroxyglycine
Authors: Sugiura Masaharu , Mori Chieko , Hirano Keiichi , Kobayashi Shū
Published: September 2005

Hydroxyglycine, the ammonia adduct of glyoxylic acid, was found to react with various allylboronates in the presence of triethylamine in methanol to give unprotected α-amino acids directly with high stereoselectivity. For instance, the reactions with (E)- and (Z)-crotylboronates afforded the corresponding anti- and syn-crotylated products (isoleucine and alloisoleucine after hydrogenation) with high diastereoselectivity, respectively. Interestingly, it was found that isomerization of the products (γ-adducts to α-adducts) occurred under the reaction conditions in some cases. Control experiments have suggested that the isomerization took place via 2-aza (or azonia) Cope rearrangement of imines derived from γ-adducts and glyoxylic acid.Key words: hydroxyglycine, glyoxylic acid, allylboronates, α-amino acids, allylglycines, isoleucine, alloisoleucine, stereoselective reactions, isomerization, 2-aza (azonia) Cope rearrangement.
Reaction of [Fe(CO)4(η2-Me3SiC≡CSiMe3)] with PMe3 CO rather than alkyne substitution
Authors: Dennett James NL , Ferguson Michael J , McDonald Robert , Takats Josef
Published: September 2005

Reaction of [Fe(CO)4(η2-BTMSA)] (1) (BTMSA = Me3SiCCSiMe3) with trimethylphosphine proceeds by stepwise loss of CO ligands yielding [Fe(CO)3(PMe3)(η2-BTMSA)] (2) and [Fe(CO)2(PMe3)2(η2-BTMSA)] (3), respectively. This demonstrates the CO dissociative nature of substitution in 1 toward PMe3, as established in analogous M(CO)4(η2-alkyne) (M = Fe, Ru, Os) compounds. The structures of all three compounds have been determined by X-ray crystallography to assess the effect of CO substitution by PMe3on the metalalkyne bonding in these molecules.Key words: iron, carbonyl, alkyne, substitution, phosphine, steric effects.
Synthesis and conformational analysis of disaccharide analogues containing disulfide and selenosulfide functionalities in the interglycosidic linkages
Authors: Chakka Nagasree , Johnston Blair D , Pinto B Mario
Published: September 2005

The synthesis of novel disaccharides containing disulfide (methyl-4-S-(β-D-galactopyranosyl-1'-thio)-4-thio-α-D-glucopyranoside (1)) and selenosulfide (methyl-4-Se-(β-D-galactopyranosyl-1'-thio)-4-seleno-α-D-glucopyranoside (2)) functionalities in the interglycosidic linkages is described. The synthetic strategy relied on the reaction of a β-glycosylthiosulfonate with a carbohydrate thiol or selenol nucleophile. The resulting protected β-dihetero-linked disaccharides were deprotected to give the target compounds. The conformational preferences of these dihetero analogues were inferred from NOESY experiments and line-broadening effects in variable-temperature NMR spectra, and are rationalized in terms of molecular orbital theory. Low-energy conformations of these compounds can populate regions of conformational space not usually occupied by β-linked disaccharides, and offer the possibility for presentation of novel ligand topographies.Key words: disaccharides, disulfides, selenosulfides, interglycosidic linkages, conformations, MO explanation.
Synthesis of N-substituted isoindolinones via a palladium catalysed three-component carbonylation  amination  Michael addition cascade
Authors: Grigg Ronald , Gai Xinjie , Khamnaen Tossapol , Rajviroongit Shuleewan , Sridharan Visuvanathar , Zhang Lixin , Collard Simon , Keep Ann
Published: September 2005

We herein describe a novel palladium catalysed three-component cascade process involving carbonylation of an aryl iodide to generate an acyl palladium(II) species that is intercepted by a primary aliphatic or aromatic amine, amide, or sulfonamide followed by intramolecular Michael addition to furnish N-substituted isoindolinones in good yield. Overall, the cascade results in the formation of one CC and two CN bonds, one ring and one stereocentre.Key words: isoindolinone, palladium, cascade, amidation, sulfonamidation.
Novel nitrogen containing chelating ligands from aziridines  Preparation, coordination studies, and catalytic application in the cyclopropanation of styrene
Authors: Krasnova Larissa B , Yudin Andrei K
Published: September 2005

Novel ligands have been synthesized by the reaction of readily available aziridines with appropriate nitrogen based nucleophiles under mild conditions. Complexes of different stoichiometry can be readily obtained upon reaction between these ligands and the corresponding copper salts. The enantiomerically pure form of one of the ligands was obtained and applied in the styrene cyclopropanation reaction, where the copper catalyst revealed unexpectedly high diastereoselectivity in comparison with the known systems.Key words: ligands, aziridines, cyclopropanation, copper catalysts, metal complexes.
An Evaluation of the Cun Measurement System of Acupuncture Point Location
Authors: Yin Chang Shik , Park Hi-Joon , Seo Jung-Chul , Lim Sabina , Koh Hyeong-Gyun
Published: September 2005

Locating acupuncture points reliably and reproducibly is indispensable for the scientific research of acupuncture and for assuring the best care of patients. Unreliable point location can produce confounding results for acupuncture research and clinical practice. Two traditional methods of point location are currently used, directional (F-cun) and proportional (B-cun) methods, which are collectively called the cun measurement system. Reports have been published on the validity of the cun measurement system in Australian subjects; however, as acupuncture originated in ancient East China, it is possible that anthropometric data may differ in Asian people and other races. Therefore, we measured anthropometric data according to the cun measurement system in contemporary Korean patients. The F-cun measurements were significantly different from the B-cun measurements and varied significantly according to the arbitrarily selected F-cun standard. In addition, we observed further differences of F-cun measurements in the extremities of obese subjects. We concluded that the F-cun method is unreliable and that further research should be conducted to determine a more accurate point-locating method primarily based on the B-cun method.
A Birdcage Model for the Chinese Meridian System Part VI: Meridians as the Primary Regulatory System
Authors: Yung Kaung-Ti
Published: September 2005

It is imperative to define the fundamental concepts of Qi, channels, and the meridian system of Chinese medicine in terms of scientific terminology before any meaningful and mutually beneficial dialog can begin between Chinese and Western medicine. In the Chinese theory, the meridian system as a whole is the system of the body. We propose the existence of a meridian regulatory system that governs interactions between and adjusts functions of internal organs, connects them to the body surface through a network of pathways (channels) and displays their status on the skin. The meridian systems is analyzed as a 28-leg, uniform, low pass birdcage coil, where each leg represents a channel. The channel is analyzed as a transmission line and Qi is the standing wave riding on it. Each segment in the channel is represented as a section of the transmission line and it is in natural oscillation, with its second lowest resonant frequency being the 50-round circulation frequency f50, 0.578 × 10-3 Hz .
Clinical Trial of Herbal Formula on Weight Loss in Obese Korean Children
Authors: Yoo Jung-Hee , Lee Eui-Ju , Kwak Chang-Kyu , Sohn Eun-Hae , Koh Byung-Hee , Song Il-Byung , Lee Kyung-Sub
Published: September 2005

A traditional Korean herbal formula (KH), which is based on Taeumjowi-tang, is currently the most widely used herbal formula in Korea. In this study, KH was administered to obese children for 30 days, and was found to be clinically safe and effective. The subjects were children admitted to hospital to be treated for obesity with relative body weights (%RBW) of 20% or more. Originally, there were 31 subjects, but nine dropped out during the experiment. There were eight girls and 14 boys, whose average age was 11.00 ± 2.62 years, average weight was 53.37 ± 17.29 kg , and average period (30-day amount) of KH dosage was 51.18 ± 22.58 days.

The short-term effects of KH on obese children were the reduction of their BMI from 24.34 ± 3.10 to 23.26 ± 3.00 kg/m2, of %RBW from 34.41 ± 10.90 to 25.94 ± 11.18% ( p < 0.01), of body fat mass from 17.99 ± 5.37 to 16.50 ± 4.82 kg , and of body fat from 34.16 ± 3.75 to 32.08 ± 3.15% ( p < 0.01). Concerning anthropometrical measurements, abdominal skin-fold decreased from 26.16 ± 9.08 to 22.90 ± 8.35 mm , as did subscapular skin-fold from 20.86 ± 5.20 to 18.46 ± 5.31 mm ( p < 0.01). In terms of serum lipid levels, which are indices of heart disease, their total cholesterol decreased from 195.38 ± 31.39 to 183.25 ± 33.27 mg/dl , the arteriosclerosis index from 4.100 ± 0.81 to 3.84 ± 0.64 mg/dl ( p < 0.05), and serum leptin level from 14.91 ± 6.59 to 12.24 ± 4.98 ng/ml ( p < 0.01). Concerning the safety of KH, there were no significant changes in the subjects' livers, hearts, or kidneys. Nor were there any short-term signs of clinically serious side effects or withdrawal symptoms observed. The short-term effects of KH on obese children are weight loss and a decrease in obesity.
Effects of Saponin Monomer 13 of Dwarf Lilyturf Tuber on L-Type Calcium Currents in Adult Rat Ventricular Myocytes
Authors: Tao Jin , Wang Hongyi , Chen Jiandong , Xu Huae , Li Shengnan
Published: September 2005

The saponin monomer 13 of dwarf lilyturf tuber (DT-13), one of the saponin monomers of dwarf lilyturf tuber, has been found to have potent cardioprotective effects. In order to investigate the effect of DT-13 on L-type calcium currents ( I Ca,L ), exploring the mechanisms of DT-13's cardioprotective effects, we directly measured the I Ca,L in the adult rat cardiac myocytes exposed to DT-13 using standard whole-cell patch-clamp recording technique. Our results showed that DT-13 exerted inhibitory effects on the I Ca,L of the single adult rat cardiac myocytes. The current density was reduced by about 38% after exposure of the cells to DT-13 (0.1 μM) for 10 minutes, from the control value of 7.46 ± 1.31 pA/pF to 4.25 ± 0.35 pA/pF ( n = 6, p < 0.05). This I Ca,L -inhibiting action of DT-13 was concentration-dependent. DT-13 up-shifted the current-voltage (I-V) curve, but did not significantly affect the half activation potential (V0.5). V0.5 was from -11.8 ± 0.9 mV in the control to -12.6 ± 1.9 mV in the presence of DT-13 at 0.1 μmol/L. DT-13 at 0.1 μM did not markedly affect the activation of I Ca,L , but shifted the inactivation curve of I Ca,L to the left. In combination with previous reports, these results suggest that there might be a close relationship between the cardioprotective effects of dwarf lilyturf tuber and the inhibitory effects of DT-13 on L-type calcium currents.
SYNTHESIS OF Ru1-xSbxSr2(Eu0.7Ce0.3)2Cu2O10-δ AND THEIR MAGNETIC AND TRANSPORT PROPERTIES
Authors: YANG T. R. , ILONCA G. , BEIUŞAN F. , POP A. V. , TOMA V. , MATEI I. , PATAPIS S.
Published: September 2005

Ru 1-x Sb x Sr 2( Eu 0.7 Ce 0.3)2 Cu 2 O 10-δ systems were prepared by conventional solid state reaction method. The structural analysis was investigated using X-ray diffraction. Electrical resistivity, Hall effect and magnetic susceptibility measurements on Ru :1222 doped with Sb are presented, together with results in the temperature range 5–300 K. Transition temperature decreases from 43 K for x = 0.00 to 20 K for x = 0.06 Sb . This may be due to a distortion of RuO 6 octahedral, which is responsible of the increase in hole localization. The Hall effect anomalous decreases below T magnetic which may be explained within a simple two-band model by a transition from localized to more itinerant behavior in the RuO 2 layer at T magnetic . The behavior of magnetic susceptibility is caused by an antisymmetric exchange coupling of the Dzyaloshinsky–Morya type between neighboring Ru moments.
DETECTING DEFECTS IN AIRCRAFT MATERIALS BY NUCLEAR TECHNIQUE (PAS)
Authors: BADAWI EMAD. A.
Published: September 2005

Positron annihilation spectroscopy (PAS) is one of the nuclear techniques used in material science. The present measurements are used to study the behavior of defect concentration in one of the most important materials — aluminum alloy — which is a 7075 alloy. It has been shown that positrons can become trapped in imperfect locations in solids and their mean lifetime can be influenced by changes in the concentration of such defects. No changes have been observed in the mean lifetime values after the saturation of defect concentration. The mean lifetime and trapping rates were studied for samples deformed up to 58.3%. The concentration of defect range varies (from 1015 to 1018 cm-3) at the thickness reduction, (from 2.3 to 58.3%). The range of the dislocation density varies (from 108 to 1011 cm/cm3).
CHERN–SIMONS–WITTEN CONFIGURATION SPACE INTEGRALS IN KNOT THEORY
Authors: HSIEH CHUN-CHUNG , YANG SU-WIN
Published: September 2005

In the context of perturbative quantum field theory, we express the first non-vanishing Massey–Milnor linkings in terms of Chern–Simons–Witten configuration space integrals in knot theory.
ON THE IMAGE OF THE LAWRENCE–KRAMMER REPRESENTATION
Authors: BUDNEY RYAN D.
Published: September 2005

A non-singular sesquilinear form is constructed that is preserved by the Lawrence–Krammer representation. It is shown that if the polynomial variables q and t of the Lawrence–Krammer representation are chosen to be appropriate algebraically independent unit complex numbers, then the form is negative-definite Hermitian. Using the fact that non-invertible knots exist this result implies that there are matrices in the image of the Lawrence–Krammer representation that are conjugate in the unitary group, yet the braids that they correspond to are not conjugate as braids. The two primary tools involved in constructing the sesquilinear form are Bigelow's interpretation of the Lawrence–Krammer representation, together with the Morse theory of functions on manifolds with corners.
COMPUTING THE A-POLYNOMIAL USING NONCOMMUTATIVE METHODS
Authors: NAGASATO FUMIKAZU
Published: September 2005

In this paper we give a formula for the A-polynomial of the (2, 2p + 1)-torus knot, for any integer p, by using noncommutative methods (the Kauffman bracket skein modules).
A FRAMEWORK FOR ADAPTIVE AND DYNAMIC COMPOSITION OF WEB SERVICES
Authors: MAHMOUD QUSAY H. , ZAHREDDINE WASSAM
Published: September 2005

The modularity of web services has left an open problem in composition, a scenario that involves an amalgamation of two or more web services to fulfill a request that no one web service is able to provide. This paper presents a framework for adaptive and dynamic composition of web services, enabling web services to be discovered either statically or dynamically by utilizing a semantic ontology to describe web services and their methods. This novel approach gives greater control on how web services are dynamically discovered by allowing the application developer to specify how matches are made, which goes beyond the present techniques of semantically matching inputs and outputs along with classification taxonomies. We utilize the Composite Capabilities/Preferences Profiles (CC/PP) to adapt the interface and content to be compatible with virtually any device. A proof of concept implementation has been constructed that enables users of any device to dynamically discover context-based services that will be dynamically composed to satisfy a user's request. In addition, we have designed and implemented a UDDI-like registry to support context-based adaptive composition of web services. Existing web services can be easily adapted and new web services can be effortlessly deployed.
ON ARCHITECTURE FOR SLA-AWARE WORKFLOWS IN GRID ENVIRONMENTS
Authors: Quan Dang Minh , Kao Odej
Published: September 2005

Service Level Agreements (SLAs) are currently one of the major research topics in Grid Computing, as they serve as a foundation for reliable and predictable Grids. SLAs define an explicit statement of expectations and obligations in a business relationship between provider and customer. Thus, SLAs should guarantee the desired and a-priori negotiated Quality of Service (QoS), which is a mandatory prerequisite for the Next Generation Grids. This development is proved by a manifold research work about SLAs and architectures for implementing SLAs in Grid environments. However, this work is mostly related to SLAs for standard, monolithic Grid jobs and neglects the dependencies between different steps of operation. The complexity of an SLA-specification for workflows grows significantly, as characteristics of correlated sub-jobs, the data transfer phases, the deadline constraints and possible failures have to be considered. Thus, an architecture for an SLA-aware workflow implementation needs sophisticated mechanisms for specification and management, sub-job mapping, data transfer optimization and fault reaction. Therefore, this paper presents an architecture for SLA-aware Grid workflows. The main contributions are an improved specification language for SLA-aware workflows, a mapping and optimization algorithm for sub-job assignment to Grid resources and a prototype implementation using standard middleware. Experimental measurements prove the quality of the development.
EFFICIENT BROADCAST INDEXING SCHEME FOR LOCATION-DEPENDENT QUERIES IN MULTI CHANNELS WIRELESS ENVIRONMENT
Authors: WALUYO AGUSTINUS BORGY , SRINIVASAN BALA , TANIAR DAVID
Published: September 2005

Data dissemination scheme has been of great interest due to its scalability. In mobile environment, the advantage of such scheme is significant considering the inherent limitations of wireless environment. The application of broadcast indexing scheme in a wireless broadcast environment is necessary to help mobile clients to find the desired data instances efficiently. In this paper, we present a novel index structure called global indexing scheme for location-dependent queries. The proposed scheme is applied in a multi channel wireless environment and designed to serve queries efficiently in which the queries result depend on the mobile clients' current location. We develop a simulation model to find out the access time, tuning time and power consumption performance of global indexing scheme as compared to non-global indexing scheme. Additionally, we analyse the efficiency of valid scope used in the global index scheme as compared with an existing valid scope. It is found that global index performs substantially better than the existing indexing concept.
A SWITCHED ETHERNET PROTOCOL FOR HARD REAL-TIME EMBEDDED SYSTEM APPLICATIONS
Authors: YIMING ALIMUJIANG , EISAKA TOSHIO
Published: September 2005

This paper presents a protocol to support hard real-time traffic of end-to-end communication over non real-time LAN technology. The network is set up with nodes and switches, and real-time communication is handled by software (protocol) added between the Ethernet protocols and the TCP/IP suite. The proposed protocol establishes a virtual circuit based on admission control and manages hard real-time traffic to bypass the TCP/IP stack. This makes considerably reduce the dwell time in the nodes, and increase the achievable data frame rate. After the bypassing, traffic schedule is performed according to dynamic-priority EDF algorithm. The work does not need any modifications in the Ethernet hardware and coexists with TCP/IP suites, and then the LAN with the protocol can be connected to any existing Ethernet networks. It can be adopted in industrial hard real-time applications such as embedded systems, distributed control systems, parallel signal processing and robotics. We have performed some experiments to evaluate the protocol. Compared to some conventional hard real-time network protocols, the proposed one has better real-time performances and meets the requirements of reliability for hard real-time systems.
HYBRID QUANTUM MECHANICAL/MOLECULAR MECHANICAL APPROACH TO ENZYMATIC REACTIONS BY UTILIZING THE REAL-SPACE GRID TECHNIQUE
Authors: HORI TAKUMI , TAKAHASHI HIDEAKI , NITTA TOMOSHIGE
Published: September 2005

We have developed a novel quantum mechanical/molecular mechanical (QM/MM) code based on the real-space grids in order to realize high parallel efficiency. The details of the methodology and its parallel implementation have been presented. We have computed the electronic state of the QM subsystem using the Kohn–Sham density functional theory, where the one-electron wave functions have been expressed by the real-space grids distributed over a cubic cell. We have performed QM/MM simulations for the peptide hydrolysis in human immunodeficiency virus type-1 aspartyl protease in order to examine the reliability of the present QM/MM approach. The activation energy obtained by the present calculations shows a good agreement with the experimental results and that of the other QM/MM method. Finally, we have parallelized the whole code and found that the grid approach can afford high parallel efficiency (~80%) in such a large scale electronic structure calculation. We conclude that the QM/MM approach utilizing real-space grids is adequate and efficient for the study of the enzymatic reactions.
VALIDITY AND INTERPRETATION OF HUND'S MULTIPLICITY RULE FOR MOLECULES: A DENSITY FUNCTIONAL STUDY
Authors: ZHONG AIGUO , LIU SHUBIN
Published: September 2005

Validity and interpretation of Hund's multiplicity rule for one molecular system, boron hydride, is investigated from the density functional framework in the present work. Performance of a number of approximate exchange-correlaton energy denstiy functionals from LDA, GGA and hybrid models have been examined. It has been shown that all approximate functionals are able to predict the correct energy order, both adiabatically and vertically, for different spin states of the molecule, reproducing that a higher spin state from the same electronic configuration possesses a lower total energy. It is only the hybrid functionals, however, that render the picture derived for the exact density functionl theory of excited states and multiplets, that is, the validity of Hund's rule can be interpreted by the sole contribution from the outmost orbital (i.e. HOMO) of the spin states. Systematic discrepancy between the total and HOMO energy differences have been observed for both LDA and GGA forms, indicating that they are not as good in simulating the same-spin electron correlation effect as the Hartree–Fock method. We also show that it is the same as what we have found from the Hartree–Fock theory, and justification via either the nuclear-electron attraction or the exchange energy alone is not adequate to interpret the validity of the rule.
DENSITY FUNCTIONAL THEORY STUDY OF THE INTERACTION BETWEEN 3-NITRO-1,2,4-TRIAZOLE-5-ONE AND WATER
Authors: FANG GUO-YONG , XU LI-NA , HU XIN-GEN , LI XIN-HUA , XIAO HE-MING , JU XUE-HAI , GONG XUE-DONG
Published: September 2005

Three fully optimized geometries of 3-nitro-1,2,4-triazol-5-one (NTO)-H2O complexes have been obtained with density function theory (DFT) method at the B3LYP/6-311++G** level. The intermolecular interaction energy is calculated with zero point energy (ZPE) correction and basis set superposition error (BSSE) correction. The greatest corrected intermolecular interaction of the NTO–H2O complexes is -30.14 KJ/mol. Electrons in complex systems transfer from H2O to NTO . The strong hydrogen bonds contribute to the interaction energies dominantly. Natural bond orbital (NBO) analysis is performed to reveal the origin of the interaction. Based on the vibrational analysis, the changes of thermodynamic properties from the monomer to complexes with the temperature ranging from 200 K to 800 K have been obtained using the statistical thermodynamic method. It is found that three NTO –water complexes can be produced spontaneously from NTO and H2O at lower temperature.
THE FAILURE OF CS APPROXIMATION IN QUANTUM REACTION SCATTERING WITH DOUBLE DEEP WELL: TIME-DEPENDENT CALCULATION FOR O + NH REACTION
Authors: WANG DONGSHENG , YANG MINGHUI , HAN KE-LI , ZHANG DONGHUI
Published: September 2005

The present paper shows the failure of CS (centrifugal sudden or coupled states) approximation in the time-dependent (TD) quantum wave packet calculation for the exoergicity reaction O + NH on the 1A′ potential energy surface [Guadagnini, Schatz and Walch, J Chem Phys102:774 (1995)] that has double deep wells. In order to show this, total reaction probabilities and rate constants for the title reaction are presented in this study with the CS approximation and the CC (close-coupling) method, respectively. The results show that by carrying out the wave packet propagation to several picoseconds with the CC method, we can resolve all the resonance features for the title reaction and the differences between the CS and the CC become larger as J becomes larger. When J becomes larger the agreement between the CS and the CC gets progressively worse. The failure of the CS approximation can be explained with the results of double deep wells, which cause long propagation time and make the coupling of K states important.
SUSTAINABLE PLANNING: THE NEED FOR STRATEGIC ENVIRONMENTAL ASSESSMENT-BASED MUNICIPAL PLANNING IN SAUDI ARABIA
Authors: ALSHUWAIKHAT HABIB M. , AINA YUSUF A.
Published: September 2005

The Saudi government has made some efforts in incorporating the principles of sustainable development into the planning process by establishing a framework for considering environmental consequences of development activities. The framework is guided by the General Environmental Code. The Ministerial Committee on the Environment (MCE) coordinates the environmental assessment of plans, policies and programmes prior to approval. However, the framework tends to focus on plans and programmes at the national level with little or no explicit provision for ensuring the assessment of municipal plans, policies and programmes. This paper evaluates the integration of environmental assessment into the municipal planning process and the plan documents. The findings indicate that the implementation of environmental assessment at the municipal planning level is minimal. Inadequate institutional framework and lack of effective environment assessment legislation are the main barriers to the implementation. Overall, the assessment shows that there is the need to improve sustainability planning practice in the Kingdom.
LEGAL STRUCTURE OF PUBLIC PARTICIPATION IN ENVIRONMENTAL ISSUES IN TURKEY
Authors: GÜNEŞ YUSUF , COŞKUN AYNUR AYDIN
Published: September 2005

Dealing with environmental problems, "participation" has emerged as a central theme. There has, for some time, been a growing recognition within the government and society at large that the future of Turkish environmental protection depends on more effective participation of multiple stakeholders. Along with growing appreciation of the potential benefits has come more systematic understanding of the factors that currently inhibit wider and more effective use of participatory techniques in Turkey. Over the last decade, there has been a succession of studies pointing to the conclusion that current environmental practices, entrenched institutional arrangements and attitudes, and poorly adapted laws are major constraints on participatory approaches. With specific reference to the legal framework, there is a growing consensus that Turkish legislation falls short in comparison to those in most developed countries and acts as a constraint on participation because of its command and control approach, in which most decisions are made by the state and the principal role of law is to ensure compliance and penalise non-compliance with those decisions. The law does not fully reflect current social, economic and environmental realities. The purpose of this study is to focus on the strengths and weaknesses of Turkey's environmental law per se, by highlighting some international lessons and practices that might be useful to Turkey as it considers what future steps to take in improving the legal framework for participation. The 1998 case in which the environmentally damaging activities of the Eurogod Mining Company at Bergama, Western Turkey, were stopped following a petition by local people to the Appeals Court is cited as an example. This case study reflects the people's participation in environmental issues and supports the main argument of this article, from which recommendations are made for improving the legal outline for participation.
DEFECATION BEHAVIOR AND ECOLOGY OF INSECTS
Authors: Weiss Martha R.
Published: September 2005

▪ Abstract  Whereas foraging has been a major focus of ecological and entomological research, its obligate partner, defecation, has been comparatively neglected. Insects exhibit a range of intriguing behavioral and morphological adaptations related to waste disposal in a range of contexts, including predator-prey interactions, hygiene, habitat location, reproduction, feeding, and shelter construction. Some insects, for example, make use of their own excrement as a physical or chemical defense against natural enemies, while others actively distance themselves from their waste material. Internally feeding insects, fluid-feeders, and social insects face particular challenges because their feeding behavior and/or site fidelity makes them especially vulnerable to problems associated with waste accumulation. As is true for foraging, ecological interactions involving defecation may have far-reaching evolutionary consequences and merit further study.
ASSESSING RISKS OF RELEASING EXOTIC BIOLOGICAL CONTROL AGENTS OF ARTHROPOD PESTS
Authors: van Lenteren J.C. , Bale J. , Bigler F. , Hokkanen H.M.T. , Loomans A.J.M.
Published: September 2005

▪ Abstract  More than 5000 introductions of about 2000 species of exotic arthropod agents for control of arthropod pests in 196 countries or islands during the past 120 years rarely have resulted in negative environmental effects. Yet, risks of environmental effects caused by releases of exotics are of growing concern. Twenty countries have implemented regulations for release of biological control agents. Soon, the International Standard for Phytosanitary Measures (ISPM3) will become the standard for all biological control introductions worldwide, but this standard does not provide methods by which to assess environmental risks. This review summarizes documented nontarget effects and discusses the development and application of comprehensive and quick-scan environmental risk assessment methods.
Celiac Disease
Authors: Green Peter H.R. , Jabri Bana
Published: September 2005

Celiac disease is an autoimmune disease that occurs in genetically predisposed individuals as the result of an immune response to gluten. This immune response occurs in both the lamina propria and the epithelium of the small intestine. There is a close link to HLA DQ2 and DQ8, although these HLA genes account for only 40% of the genetic influence. Environmental factors, such as the amount and timing of gluten administration in infancy, as well as breastfeeding, influence the disease. Serologic screening studies that use sensitive and specific antibody tests have revealed the disease to be common, occurring in ∼1% of the population. Clinical presentations are diverse and atypical; the majority of patients lack diarrhea. Therapy is a gluten-free diet that requires avoidance of wheat, rye, and barley, although there is potential for other therapies based on our understanding of the pathophysiology of the disease.
Brain oxygen utilization is unchanged by hypoglycemia in normal humans: lactate, alanine, and leucine uptake are not sufficient to offset energy deficit
Authors: Lubow Jeffrey M. , Piñón Ivan G. , Avogaro Angelo , Cobelli Claudio , Treeson David M. , Mandeville Katherine A. , Toffolo Gianna , Boyle Patrick J.
Published: September 2005

During hypoglycemia, substrates other than glucose have been suggested to serve as alternate neural fuels. We evaluated brain uptake of endogenously produced lactate, alanine, and leucine at euglycemia and during insulin-induced hypoglycemia in 17 normal subjects. Cross-brain arteriovenous differences for plasma glucose, lactate, alanine, leucine, and oxygen content were quantitated. Cerebral blood flow (CBF) was measured by Fick methodology using N2O as the dilution indicator gas. Substrate uptake was measured as the product of CBF and the arteriovenous concentration difference. As arterial glucose concentration fell, cerebral oxygen utilization and CBF remained unchanged. Brain glucose uptake (BGU) decreased from 36.3 ± 2.6 to 26.6 ± 2.1 μmol·100 g of brain−1·min−1( P < 0.001), equivalent to a drop in ATP of 291 μmol·100 g−1·min−1. Arterial lactate rose ( P < 0.001), whereas arterial alanine and leucine fell ( P < 0.009 and P < 0.001, respectively). Brain lactate uptake (BLU) increased from a net release of −1.8 ± 0.6 to a net uptake of 2.5 ± 1.2 μmol·100 g−1·min−1( P < 0.001), equivalent to an increase in ATP of 74 μmol·100 g−1·min−1. Brain leucine uptake decreased from 7.1 ± 1.2 to 2.5 ± 0.5 μmol·100 g−1·min−1( P < 0.001), and brain alanine uptake trended downward ( P < 0.08). We conclude that the ATP generated from the physiological increase in BLU during hypoglycemia accounts for no more than 25% of the brain glucose energy deficit.
Increased circadian prolactin release is blunted after body weight loss in obese premenopausal women
Authors: Kok Petra , Roelfsema Ferdinand , Langendonk Janneke G. , de Wit Caroline C. , Frölich Marijke , Burggraaf Jacobus , Meinders A. Edo , Pijl Hanno
Published: September 2005

We recently showed that prolactin (PRL) release is considerably enhanced in obese women in proportion to the size of their visceral fat mass. PRL release is inhibited by dopamine 2 receptor (D2R) activation, and dietary restriction/weight loss are associated with increased dopaminergic signaling in animals. Therefore, we hypothesized that enhanced PRL release in obese humans would be reversed by weight loss. To evaluate this postulate, we measured 24-h plasma PRL concentrations at 10-min intervals in 11 obese premenopausal women (BMI 33.3 ± 0.7 kg/m2) before and after weight loss (50% reduction of overweight/15% absolute weight loss, using a very low-calorie diet) in the follicular phase of their menstrual cycle. The 24-h PRL concentration profiles were analyzed by a peak detection program (Cluster) and a wave form-independent deconvolution technique (Pulse). Spontaneous 24-h PRL secretion was significantly reduced in obese women [mean daily release, before 128 ± 24 vs. after weight loss 110 ± 17 μg/liter distribution volume (Vdl)−1 × 24 h, P = 0.05]. Body weight loss particularly blunted PRL secretory burst mass (Pulse area, before 230 ± 28 vs. after weight loss 221 ± 31 μg/Vdl−1 × 24 h, P = 0.03), whereas burst frequency was unaffected (no. of pulses, before 11 ± 1 vs. after weight loss 12 ± 1 n/24 h, P = 0.69). Thus elevated PRL secretion rate in obese women is significantly reduced after loss of 50% of overweight. We speculate that amelioration of deficit D2R-mediated neurotransmission and/or diminutions of circulating leptin/estrogen levels might be involved in the physiology of this phenomenon.