bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics of the cyclotrimerization and cocyclotrimerization of isocyanates catalyzed with alkali metals alkoxides
Authors: Bukač Zbyněk , Nechaiev Alexandr , Šebenda Jan
Published: August 2011

For the rate of cyclotrimerization vt of phenyl isocyanate (I) in tetrahydrofuran catalyzed with Li, Na or K tert-butoxides (A) at 30 °C, the coefficients k, a, b of the empirical relation vt = k[I]a[A]0b were determined. The same coefficients were also determined for the cyclotrimerization of ethyl isocyanate with lithium tert-butoxide as the catalyst. The composition of the products of cocyclotrimerization of ethyl and butyl isocyanate corresponds to ratios of the rates of trimerization of the individual isocyanates. With respect to the fast decay of initiator in acetonitrile, data reported in the literature on the rate of cyclotrimerization in this solvent are not real.
Liquid-phase aldol condensation of cyclohexanone on aluminium and iron oxides
Authors: Vít Zdeněk , Nondek Lubomír , Málek Jaroslav
Published: August 2011

The kinetics of the aldol condensation of cyclohexanone in decalin were investigated at 210 °C on catalysts prepared by drying and calcining the aluminium and iron hydroxides at 110-850 °C. The effect of catalyst poisoning by benzoic acid and pyridine on the course of the condensation reaction and aldol retroaldolisation was also examined. The kinetics of the cyclohexanone condensation can be described by means of Langmuir-Hinshelwood equations which are in agreement with a mechanism involving adsorption of cyclohexanone on a basic site to form a transient complex, reaction of this complex with a cyclohexanone molecule affording the aldol, the rate determining interaction of the aldol with free basic and acid sites yielding 2-(1-cyclohexen-1-yl)cyclohexanone and water and desorption of these products from the catalyst surface. The proposed kinetic model is supported by the results of catalyst poisoning. The activity of aluminium and iron oxides in the condensation of cyclohexanone is a complex function of their basicity and acidity depending strongly on the calcination temperature.
1-Aminocyclopropanecarboxylic acid and its derivatives
Authors: Procházka Zdenko , Buděšínský Miloš , Smolíková Jorga , Trška Petr , Jošt Karel
Published: August 2011

Action of strongly basic reagents on methyl Nα-benzyloxycarbonylamino-γ-bromobutyrate leads to 1-aminocyclopropanecarboxylic acid derivatives whose structure was determined by 1H NMR, 13C NMR and IR spectroscopy. According to IR spectroscopy, the urethane CO-NH group in crystalline methyl 1-benzyloxycarbonylaminocyclopropanecarboxylate exists in the cis(E) conformation which on dissolution is transformed into the trans(Z) form. NMR spectroscopy showed that the acid-catalyzed esterification of α-amino-γ-bromobutyric acid is accompanied by replacement of the covalently bonded bromine by chlorine.
Preparation of 1,6:3,4-dianhydro-β-D-altropyranose as starting substance for the synthesis of 3-substituted D-mannose derivatives
Authors: Doležalová Jitka , Trnka Tomáš , Černý Miloslav
Published: August 2011

Acetolysis of 1,6 : 3,4-dianhydro-2-O-p-toluenesulfonyl-β-D-galactopyranose (I) gave 3,4-di-O-acetyl-1,6-anhydro-2-O-p-toluenesulfonyl-β-D-glucopyranose (II) which was converted with sodium methoxide to 1,6 : 3,4-dianhydro-β-D-altropyranose (X). The 1,6-anhydride bond in diacetate II was cleaved with acetic anhydride or hydrogen bromide in acetic acid under formation of a mixture of anomeric tetraacetates of 2-O-p-toluenesulfonyl-D-glucopyranose or the corresponding acetates of α-D-glucopyranosyl bromide XIII and its 6-bromo-6-deoxy derivative XIV.
Synthesis of 19-hydroxylated analogues of androstenedione and testosterone with the cyclopropane ring in 4,5-position
Authors: Joska Jiří , Fajkoš Jan
Published: August 2011

Synthesis of 19-hydroxylated analogues of androstenedione and testosterone carrying the cyclopropane ring in position 4β,5β is described. The starting allylic alcohol XIII was prepared by standard reactions from the epoxide I and transformed by Simmons-Smith methylenation to the cyclopropano derivative XXI. Hydrolyses and oxidations afforded the desired analogues XXIII and XXV.
Stereospecific total synthesis of (+)-18-methylenevincadifformine
Authors: Hájíček Josef , Trojánek Jan
Published: August 2011

The synthesis and the resolution of (±)-18-methylenevincadifformine (VIII) is described. Its key step is the reaction of methyl 1-methyl-1,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole-1-carboxylate (XIII) with 2-allyl-5-chloropentanal (XVI).
The stoichiometry of the thermal decomposition and stereochemistry of complex compounds of the Ni(NCS)2(4-R-pyridine)4 type and their decomposition products
Authors: Jamnický Miroslav , Jóna Eugen
Published: August 2011

The stoichiometry of the thermal decomposition of the following compounds was studied: Ni(NCS)2(4-EtPy)4 (I) (Et = ethyl, Py = pyridine), Ni(NCS)2(4-ClPy)4 (II), Ni(NCS)2(4-BrPy)4 (III), Ni(NCS)2(4-CNPy)4 (IV) and Ni(NCS)2(4-NH2Py)4 (V). In complexes I and II, the loss of the volatile ligands R-Py (on the TG curve up to 573 K) occurs in two steps (-2, -2), and in complex IV in three steps (-2; -1.4; -0.6). Decomposition of the complexes III and V is accompanied by ligand decomposition. The spectral data and magnetic moment values for all the initial complexes, together with the defined intermediates with composition Ni(NCS)2(4-RPy)2, indicated pseudooctahedral configuration.
Voltamperometry of nitrate and iodate ions on rotating disc electrodes from cupper-cadmium alloy
Authors: Kvaratskheliya R. K. , Machavariani T. Sh.
Published: August 2011

Abstract in Russian
Kinetics of hydrolysis and rearrangements of S-acylthiouronium salts
Authors: Kaválek Jaromír , Novák Jaroslav , Štěrba Vojeslav
Published: August 2011

Kinetics of transformation of S-acetyl- and S-benzoylisothiouronium chlorides have been followed, and its reaction products in dilute hydrochloric acid media and aqueous buffers have been identified. In dilute hydrochloric acid the reaction rate is pH-independent, and the acetyl derivative reacts 8 times as rapidly as the benzoyl derivative. In acetate and phosphate buffers the decomposition rate of the both derivatives increases linearly with the buffer concentration. In acetate buffers the reaction rate is pH-independent, and acetate ion reacts as a nucleophile. In phosphate buffers the rate increases with increasing pH. The reaction catalyzed by the basic buffer component produces thiourea and carboxylic acid, that catalyzed by hydroxyl ion produces N-acetyl- or N-benzoylthiourea. The solvolysis rates of both S-acyl derivatives depend on percent composition of water-methanol solvent. The maximum solvolysis rate is reached in methanol with 25% (v/v) water.
Conformation studies of isomeric 1-acyloxy-2-(4-methoxybenzyl)-cyclohexanes by 1H NMR spectroscopy
Authors: Buděšínský Miloš , Šaman David , Wimmer Zdeněk
Published: August 2011

The conformation of the cyclohexane ring and the p-methoxybenzyl substituent in the series of isomeric 1-acyloxy-2-(4-methoxybenzyl)cyclohexanes was studied by means of 1H NMR spectroscopy. In all the substances investigated the cyclohexane ring assumes chair conformation. trans-Isomers have both substituents in equatorial positions, while in cis-isomers the p-methoxybenzyl group is always equatorial and the hydroxy or acetoxy group axial.
The electronic spectra of the bis(dithiocarbamate) chelates of Cu(II) and Zn(II)
Authors: Oktavec Drahomír , Štefanec Jozef , Síleš Bohumil , Beinrohr Ernest , Konečný Václav , Garaj Ján
Published: August 2011

This work deals with the synthesis of dithiocarbamate chelates of Cu(II) and Zn(II) with ligands derived from dimethyl-, diethyl-, dipropyl-, dibutyl- and methylisopropylamine, piperidine and morpholine and the electronic spectra of these substances in the UV and visible regions. The absorption spectra of the cupric (and zinc(II)) chelates contain a single analytically important band around 270 (260) nm, assigned to the π-π* transition within the ligand, that is affected by the substituent on the nitrogen atom and the solvent polarity. Lengthening of the alkyl chain leads to increased intensity of the bands and a red shift of their λmax; increased solvent polarity leads to increased intensity of the bands and a blue shift.
Reaction of 4-chlorobenzenediazonium chloride with L-proline, sarcosine, and DL-alanine
Authors: Mejstřík Viktor , Gryga Petr , Matrka Miroslav
Published: August 2011

The rates of reactions of substituted phenyldiazonium salts with the title amino acids were estimated in the pH range 6.5-10.5. The reaction product of 4-chlorobenzenediazonium chloride and L-proline was isolated and its triazene structure was shown.
Inductive effect in EI-mass spectra of some 5,6-dihalogenides and 5,6-halohydrins of 5α-cholestan-3β-ol and 3β-acetoxy-5α-cholestane
Authors: Trka Antonín , Kasal Alexander
Published: August 2011

Partial EI-mass spectra of 3β-hydroxy- and 3β-acetoxy-5α-cholestanes substituted in positions 5α-, 6β- or 5α,6β- with a hydroxyl group or halogen atoms (fluorine, chlorine, bromine) are presented. The molecular ions of 5α,6β-disubstituted derivatives of 3β-hydroxy-5α-cholestane (or of its 3-acetate) are considerably more stable than the corresponding monosubstituted derivatives if at least one of the pair of the vicinal substituents is chlorine or fluorine. This increase in stability, most striking in 5α- and 6β-fluoro compounds, is explained by the inductive effect.
Preparation of the 1-(2,5-anhydro-β-d-arabinofuranosyl) derivatives of cytosine and uracil and their cleavage with hydrogen bromide
Authors: Hřebabecký Hubert , Brokeš Josef , Beránek Jiří
Published: August 2011

Anhydronucleoside Ia was prepared from chloroarabinofuranosylcytosine IIIc or from 2,2'-anhydro-1-(5-chloro-5-deoxy-β-D-arabinofuranosyl)cytosine by the action of a strongly basic ion exchanger. The anhydro derivative IIa was prepared from 2,2'-anhydro-1-(5-chloro-5-deoxy-β-D-arabinofuranosyl)uracil by treatment with aqueous solution of sodium hydroxide. The action of hydrogen bromide in dimethylformamide on 2',5'-anhydronucleosides Ia and IIa leads both to the cleavage of the anhydro bond under formation of the 5'-bromo derivatives IIIa and IVa and to the cleavage of nucleosidic bond. In case of the uracil derivative IIa, the α-arabinofuranosyl derivative V was also isolated after preceding acetylation. For unambiguous proof of the structure, an alternative synthesis of compound V was performed.
Quantum-chemical MO study of protonation of 1-methyl-1,4-dihydronicotinamide
Authors: Krechl Jiří , Böhm Stanislav , Kuthan Josef
Published: August 2011

The methods EHT, CNDO/2, MNDO and ab initio STO-3G have been used to study regioselectivity of protonation of 1-methyl-1,4-dihydronicotinamide (I, R = CH3). The results obtained are discussed in relation to lability of the NAD(P)H coenzymes in acid media and agree well with experimantal findings.
Neighboring group participation in hypobromous acid addition to 19-substituted 5α-cholest-1-enes and in acid cleavage of their epoxy analogs
Authors: Černý Václav , Kočovský Pavel
Published: August 2011

Reactions of the title compounds (bearing an OH, OCH3 or OCOCH3 group at C(19)) involve 5(O)n, 7(O)π,n-participation by the 19-substituent or attack by an external nucleophile. The 6(O)π,n-participation does not occur. The behavior of 1,2-unsaturated (or epoxidated) compounds has been compared with the earlier described 2,3-unsaturated or epoxidated analogs. The 1,2-type is genarally less prone to participation. The reasons for this behavior are discussed.
Desulfuration of steroidal thians
Authors: Kasal Alexander
Published: August 2011

The reaction of 4-thia-5-cholesten-3-one (X) with Raney nickel in protic medium affords alcohol III, while A-nor-5β-cholestan-3-one (XXIII), A-bisnor-2,5-secocholestane (XXXI) and the esters of the type XVIII are formed as by-products. When aprotic medium is used compounds XXIII and XXXI are the main products. During desulfuration with a less active Raney nickel the mentioned substances are accompanied by 5-unsaturated derivatives of the type I, XIV and XXIX. Optimum conditions for the preparation of either saturated alcohols of type III or of unsaturated esters of type XIV were found.
Sesquiterpenic lactones from Grossheimia macrocephala. Structure of grosheiminol
Authors: Daniewski Włodzimierz , Wawrzuń Andrzej , Błoszyk Ełżbieta , Drożdż Bohdan , Holub Miroslav
Published: August 2011

From the leaves of Grossheimia macrocephala (MUSS.-PUSCHK.) D. SOSN. et TAKHT. cynaropicrin (II), isolipidiol (III) and the so far undescribed lactone grosheiminol (IV) were isolated in addition to grosheimin (I), detected in this species earlier. For grosheiminol the structure IV was derived, including relative and absolute configuration, on the basis of chemical correlation.
Liquid-vapour equilibrium and heats of mixing in the ethanol-acetonitrile system
Authors: Dohnal Vladimír , Veselý František , Holub Robert , Pick Jiří
Published: August 2011

Vapour-liquid equilibrium and heats of mixing were measured in the ethanol-acetonitrile system. The isobaric vapour-liquid equilibrium measurements were carried out at the pressures of 43.35, 56.44, 69.48 and 86.05 kPa and the heats of mixing were measured at the temperatures of 298.15, 308.15 and 318.15 K. The individual vapour-liquid equilibrium data sets were correlated by various two-parameter equations and the data on heats of mixing by the Redlich-Kister polynomial. The extensive data obtained for both excess functions, covering the temperature range of 50 K, were correlated successfully by the Wilson equation with the energy parameters linearly dependent on temperature.
The role of inert material in an adsorption bed
Authors: Kočiřík Milan , Stárek Jiří , Smutek Miloš
Published: August 2011

An influence of the presence of inert material in an adsorption bed is studied, with special regard to the width of breakthrough curves, the breakthrough time and the efficiency and dynamic capacity of an adsorption bed. The positive influence of the inert component is due to the decrease of the effective distribution constant. This influence is reflected in the terms characterizing the axial dispersion in a bed.
Zur Rolle der Grenzschicht beim Einsatz eines Stosswellenrohres zur Untersuchung der Kinetik pyrolytischer Reaktionsvorgänge
Authors: Klotz Hans-Dieter , Drost Helmut , Maštovský Jiří
Published: August 2011

Bei Stosswellenrohr-Untersuchungen zur Kinetik der Pyrolyse einfacher Kohlenwasserstoffe (KW) ergab sich die Frage nach dem Einfluss der Grenzschicht auf das pyrolytische System und damit nach der Zuverlassigkeit der mit dem Stosswellenrohr (SR) ermittelten kinetischen Daten. Untersucht wurde der Druck und der Warmestrom durch die Grenzschicht wahrend der Athylenpyrolyse mittels am Endflansch des SR angebrachter Druckwandler und Filmthermometer. Es zeigte sich, dass im Gegensatz zu chemisch inerten in reaktiven KW-Systemen ein zusatzlicher Warmestrom zur Wand auftrifft, der mit der KW-Konzentration und der Pyrolysetemperatur zunimmt. Der zusatzliche Warmestrom wird auf chemische Prozesse, insbesondere Rekombinationen und Assoziationen, in der Grenzschicht zuruckgefuhrt. Die daraus resultierenden moglichen Konsequenzen hinsichtlich diagnostischer und kinetischer Untersuchungen zur KW-Pyrolyse im SR werden diskutiert.
Polarographic electrode process of antimony(III) complexes with complexones
Authors: Er-kang Wang
Published: August 2011

Antimonous ions yield in a solution of 4M sodium chloride a well-defined reduction wave. With increasing concentration of EDTA or CDTA a new cathodic wave appears at more negative potentials. The first (more positive) wave is kinetically controlled. We calculate the stability constant and the thermodynamic functions of antimony(III) complexone complexes from the shift of half-wave of the kinetic wave and their dissociation constant from the kinetic current under given conditions, β = 3 . 1019, kd = 2.8 . 1013 s-1 for SbY, β = 6 . 1024, kd = 8.8 . 1018 s-1 for SbZ. The rate constant of electrode reaction proper of the antimony(III) complexes with complexone is also calculated and the mechanism of the whole process is discussed.
Adsorption of carbamide and its aliphatic derivatives on the dropping mercury electrode
Authors: Masłowska Joanna , Cedzyńska Krystyna
Published: August 2011

The adsorption of carbamide and its aliphatic derivatives at the interphase mercury - electrolyte solution was studied, using the drop-time technique. The surface concentration *G of carbamide and its derivatives has been calculated for a wide range of concentrations at the selected potential. The shape of the electrocapillary curves indicates that both carbamide and its derivatives are adsorbed at the interphase mercury-electrolyte solution.
IR laser driven decomposition of oxalyl chloride in presence or radical scavengers: Evidence for molecular mechanism
Authors: Pola Josef
Published: August 2011

CO2 laser-induced and SF6 (0.4-0.5 kPa) sensitized decomposition of oxalyl chloride (4 kPa) in the presence of radical scavengers (2.6-8.7 kPa) as hydrogen, propene and nitric oxide obeys first-order kinetics and is supportive of the view that oxalyl chloride thermally decomposes by concerted molecular mechanism.
Optimization of molecular geometry of para-substituted benzoic acids and their anions by means of gradient CNDO/2 method
Authors: Böhm Stanislav , Kuthan Josef
Published: August 2011

21 conformers of benzoic acids I and corresponding anions II have been optimized by the title semiempirical MO approach. The calculated geometry characteristics are confronted systematically with X-ray diffraction data, and quality of the calculated parameters is critically evaluated.
Derivatives of 3-(D-6-methyl-8β-ergolin-I-yl)propanoic acid
Authors: Beran Miloš , Beneš Jan , Křepelka Jiří
Published: August 2011

Amide I was prepared both by hydration of nitrile III under the conditions of ion pair extraction, and from nitrile III, via methyl ester IX, hydrazide X and azide XI. Ethyl ester XII and 2-hydroxyethyl ester XIII of acid VIII were also prepared. Amide I and nitrile III in rats have a lower antinidation and antilactation activity than corresponding lower homologues, i.e. amide II and nitrile XIV.
Routine intrauterine device checks: are they advisable?
Authors: Draper Isabel B , Haque M Sayeed , McManus Richard J
Published: August 2011

Background

Patients using the intrauterine contraceptive device (IUD) were previously advised to undergo routine checks; in 2004, the National Institute for Health and Clinical Excellence stated the practice was unnecessary. This study was conducted to examine the evidence for this advice.

Methods

A retrospective examination of case records of patients of Whitehall Medical Practice, Rugby, UK who had used an IUD for a minimum of 2 years was performed. Data were extracted concerning demographic details, types of IUD used, dates of their use and of any checks, defaults from checks and side effects. Kaplan–Meier survival analysis was performed to compare outcomes in frequent and infrequent attenders, and in frequent and infrequent defaulters from checks.

Results

The study population comprised 272 individuals using a total of 423 devices. Frequent check attenders showed adverse events earlier, or at no significant time difference, to infrequent attenders.

Conclusions

Considering patients who use an IUD for a minimum of 2 years, this study found no evidence of harm occurring in those who attended infrequently compared to frequent attenders. If these data from a single practice are generalisable, after an initial check following insertion, women can be asked to attend as needed and only be recalled for smears and at the end of the life of the IUD.
Carbon dioxide enhances substance P-induced epithelium-dependent bronchial smooth muscle relaxation in Sprague–Dawley rats
Authors: El Mays Tamer Y. , Saifeddine Mahmoud , Choudhury Parichita , Hollenberg Morley D. , Green Francis H.Y.
Published: August 2011

Hypocapnia and hypercapnia constrict and relax airway smooth muscle, respectively, through pH- and calcium (Ca2+)-mediated mechanisms. In this study we explore a potential role for the airway epithelium in these responses to carbon dioxide (CO2). Contractile and relaxant responses of isolated rat bronchial rings were measured under hypocapnic, eucapnic, and hypercapnic conditions. Substance P was added to methacholine precontracted bronchial rings with and without epithelium. The role of Ca2+ was assessed using Ca2+-free solutions and a Ca2+ channel blocker, nifedipine. The effects of pH were assessed in solutions with HEPES buffer. Hypocapnic challenge increased the organ bath’s pH and increased bronchial smooth muscle resting tension. This effect was abolished with HEPES buffer and partially inhibited by nifedipine. Hypocapnic conditions suppressed substance P-induced epithelium-dependent relaxation, whereas hypercapnia augmented the response. The epithelial hypocapnic effect was pH dependent, whereas the hypercapnic effect was pH independent. CO2 had no effect on the epithelial independent smooth muscle agonists methacholine and isoproterenol. In conclusion our data indicate that, in addition to the effects of pH and Ca2+, CO2 affects airway smooth muscle by a pH-independent, epithelium-mediated mechanism. These findings could potentially lead to new treatments for asthma involving CO2-sensing receptors in the airways.
Physiology and pathophysiology of nitrosative and oxidative stress in osteoarthritic joint destruction
Authors: Ziskoven Christoph , JÄger Marcus , Kircher Jörn , Patzer Thilo , Bloch Wilhelm , Brixius Klara , Krauspe Rüdiger
Published: August 2011

Osteoarthritis (OA) is one of the most common chronic diseases, with increasing importance due to increased life expectancy. On a cellular level, the pathophysiology of joint function impairment and ultimate destruction associated with OA remains poorly understood. Free radicals are highly reactive molecules involved in both normal intracellular signal transduction and degenerative cellular processes. An imbalance between the free radical burden and cellular scavenging mechanisms, defined as oxidative stress, has been identified as a relevant factor in OA pathogenesis. This literature review elucidates the involvement of nitrosative and oxidative stress in cellular ageing in joints, cell senescence, and apoptosis. Free radical exposure is known to promote cellular senescence and apoptosis, and the involvement of radical oxygen species (ROS) in inflammation, fibrosis control, and pain nociception has been proven. A relatively novel approach to OA pathophysiology considers the joint to be a dynamic system consisting of 3, continuously interacting compartments, cartilage, synovial tissue, and subchondral bone. Current knowledge concerning free radical involvement in paracrine signalling in OA is reviewed. The interrelationship between oxidative imbalances and OA pathophysiology may provide a novel approach to the comprehension, and therefore modification, of OA disease progression and symptom control.
Dissociation of the vacuolar and macroautophagic cytopathology from the cytotoxicity induced by the lipophilic local anesthetic bupivacaine
Authors: Morissette Guillaume , Bawolak Marie-Thérèse , Marceau François
Published: August 2011

Local anesthetics, like many other cationic drugs, induce a vacuolar and macroautophagic cytopathology that has been observed in vivo and in various cell types; some also induce cytotoxicity of mitochondrial origin (apoptosis and necrosis) and it is not known whether the 2 types of toxicity overlap or interact. We compared bupivacaine with a more hydrophilic agent, lidocaine, for morphological, functional, and toxicological responses in a previously exploited nonneuronal system, primary smooth muscle cells. Bupivacaine induced little vacuolization (≥2.5 mmol/L, 4 h), but elicited autophagic accumulation (≥0.5 mmol/L, 4 h) and was massively cytotoxic at 2.5–5 mmol/L (4–24 h), the latter effect being unabated by the V-ATPase inhibitor bafilomycin A1. Lidocaine exerted little cytotoxicity at and below 5 mmol/L for 24 h, but intensely induced the V-ATPase-dependent vacuolar and autophagic cytopathology. Bupivacaine was more potent than lidocaine in disrupting mitochondrial potential, as judged by Mitotracker staining (significant proportions of cells affected in the 1–5 and 5–10 mmol/L concentration ranges, respectively). The addition of mitochondrial-inactivating toxins antimycin A and oligomycin to lidocaine (2.5 mmol/L) reproduced the profile of bupivacaine action (low intensity of vacuolization and retained autophagic accumulation). The high potency of bupivacaine as a mitochondrial toxicant eclipses the benign vacuolar and autophagic response seen with more hydrophilic local anesthetics.
INVESTIGATIONS IN THE LEE–WICK ELECTRODYNAMICS
Authors: ACCIOLY ANTONIO , GAETE PATRICIO , HELAYËL-NETO JOSÉ , SCATENA ESLLEY , TURCATI RODRIGO
Published: August 2011

We consider the Lee–Wick (LW) electrodynamics, i.e. the U(1) gauge theory where a (gauge-invariant) dimension-6 operator containing higher derivatives is added to the free Lagrangian of the U(1) sector. A quantum bound on the LW heavy particle mass is then estimated by computing the anomalous electron–magnetic moment in the context of the aforementioned model. This limit is not only within the allowed range estimated by LW, it is also of the same order as that considered in early investigations on the possible effects of the LW heavy particle in e-e+ elastic scattering. A comparative study between the LW and the Coulomb potentials is also done.
WIGGLY STRINGS OF RADIAL CONFIGURATION IN THE KERR BLACK HOLE
Authors: SUZUKI HIROMI
Published: August 2011

Previously we investigated classical motion of a string in (3+1)-dimensional spherically symmetric neutral and charged black holes. As an extension the solutions in (3+1)-dimensional axially symmetric rotating black hole are investigated. The solutions for the wiggly string exhibit open strings lying in the radial direction in the equatorial plane outside the horizon.
LIGHT SUPERSYMMETRIC DARK MATTER
Authors: BÉLANGER GENEVIEVE
Published: August 2011

The neutralino in a singlet extension of the minimal supersymmetric standard model and the mixed sneutrino in a supersymmetric model with right-handed neutrinos are two possible light dark matter candidates. Both can have a large scattering cross section on nuclei thus being compatible with recent results in direct detection experiments. A brief overview of the properties of light supersymmetric dark matter scenarios is presented.
DARK MATTER CANDIDATES IN LEFT-RIGHT SYMMETRIC MODELS
Authors: GUO WAN-LEI , WU YUE-LIANG , ZHOU YU-FENG
Published: August 2011

We discuss an extended left-right symmetric model in which the decay of DM particle is induced by tiny soft charge-conjugation violating interactions, and calculate the spectra for cosmic-ray positrons, neutrinos and gamma-rays. The DM signals in the flux of high energy neutrinos can be significantly enhanced, as the triplets couple to both charged leptons and neutrinos. The predicted neutrino-induced muon flux can be several times larger than the case in which DM particle only directly decays into charged leptons. In addition, the charged components of the triplet give extra contributions to the high energy gamma-rays through internal bremsstrahlung process.
TOP WINDOW FOR DARK MATTER
Authors: CHEUNG K. , MAWATARI K. , SENAHA E. , TSENG P.-Y. , YUAN T.-C.
Published: August 2011

We consider a scenario in which a dark matter can couple only to the top quark. The analysis is conducted by using the effective Lagrangian approach. In the light of the latest data on dark matter, we obtain a maximally allowed magnitude of the coupling between the dark matter and the top quark. The collider signature at the Large Hadron Collider is also discussed.
EFFECTS OF RESIDUE BACKGROUND EVENTS IN DIRECT DETECTION EXPERIMENTS ON IDENTIFYING WIMP DARK MATTER
Authors: SHAN CHUNG-LIN
Published: August 2011

We reexamine the model-independent data analysis methods for extracting properties of Weakly Interacting Massive Particles (WIMPs) by using data (measured recoil energies) from direct Dark Matter detection experiments directly and, as a more realistic study, consider a small fraction of residue background events, which pass all discrimination criteria and then mix with other real WIMP-induced signals in the analyzed data sets. In this talk, the effects of residue backgrounds on the determination of the WIMP mass as well as the spin-independent WIMP coupling on nucleons will be discussed.
MODIFIED GRAVITY EMERGING FROM THERMODYNAMICS AND HOLOGRAPHIC PRINCIPLE
Authors: ZHANG YI , GONG YUNGUI , ZHU ZONG-HONG
Published: August 2011

A new conception is proposed in [E. P. Verlinde, arXiv:1001.0785 [hep-th] and [T. Padmanabhan, Mod. Phys. Lett. A25 (2010) 1129] that gravity is one kind of entropic force. In this letter, we try to discuss its applications to the modified gravities by using three different corrections to the area law of entropy which are derived from the quantum effects and extra dimensions. According to the assumption of holographic principle, the number of bits N which is related to the equipartition law of energy is modified. Then, the modified law of Newton's gravity and the modified Friedmann equations are obtained by using the new notion. By choosing suitable parameters, the modified area law of entropy leads to de Sitter solutions which can be used to explain the accelerating expansion of our universe. It suggests that the accelerating phase in our universe may be an emergent phenomenon based on holographic principle and thermodynamics.
SOURCE OF CP VIOLATION FOR THE BARYON ASYMMETRY OF THE UNIVERSE
Authors: HOU GEORGE W. S.
Published: August 2011

We give a description of why the existence of a fourth generation is likely to provide enough CP violation for baryogenesis, and trace how this observation came about. We survey the current experimental and theoretical pursuits and outline a research agenda, touching upon unitarity violation and very heavy chiral quarks, and comment on how the electroweak phase transition picture might be altered.
Impact of XML Schema Evolution
Authors: Genevès Pierre , Layaïda Nabil , Quint Vincent
Published: August 2011

We consider the problem of XML Schema evolution. In the ever-changing context of the web, XML schemas continuously change in order to cope with the natural evolution of the entities they describe. Schema changes have important consequences. First, existing documents valid with respect to the original schema are no longer guaranteed to fulfill the constraints described by the evolved schema. Second, the evolution also impacts programs, manipulating documents whose structure is described by the original schema.

We propose a unifying framework for determining the effects of XML Schema evolution both on the validity of documents and on queries. The system is very powerful in analyzing various scenarios in which forward/backward compatibility of schemas is broken, and in which the result of a query may no longer be what was expected. Specifically, the system offers a predicate language that allows one to formulate properties related to schema evolution. The system then relies on exact reasoning techniques to perform a fine-grained analysis. This yields either a formal proof of the property or a counter-example that can be used for debugging purposes. The system has been fully implemented and tested with real-world use cases, in particular with the main standard document formats used on the web, as defined by W3C. The system precisely identifies compatibility relations between document formats. In case these relations do not hold, the system can identify queries that must be reformulated in order to produce the expected results across successive schema versions.
Metabolic consequences of ENPP1 overexpression in adipose tissue
Authors: Pan Wentong , Ciociola Ester , Saraf Manish , Tumurbaatar Batbayar , Tuvdendorj Demidmaa , Prasad Sneha , Chandalia Manisha , Abate Nicola
Published: August 2011

Ectonucleotide pyrophosphate phosphodiesterase (ENPP1) has been shown to negatively modulate insulin receptor and to induce cellular insulin resistance when overexpressed in various cell types. Systemic insulin resistance has also been observed when ENPP1 is overexpressed in multiple tissues of transgenic models and attributed largely to tissue insulin resistance induced in skeletal muscle and liver. Another key tissue in regulating glucose and lipid metabolism is adipose tissue (AT). Interestingly, obese patients with insulin resistance have been reported to have increased AT ENPP1 expression. However, the specific effects of ENPP1 in AT have not been studied. To better understand the specific role of AT ENPP1 on systemic metabolism, we have created a transgenic mouse model (C57/Bl6 background) with targeted overexpression of human ENPP1 in adipocytes, using aP2 promoter in the transgene construct ( AdiposeENPP1-TG). Using either regular chow or pair-feeding protocol with 60% fat diet, we compared body fat content and distribution and insulin signaling in adipose, muscle, and liver tissues of AdiposeENPP1-TG and wild-type (WT) siblings. We also compared response to intraperitoneal glucose tolerance test (IPGTT) and insulin tolerance test (ITT). Our results show no changes in Adipose ENPP1-TG mice fed a regular chow diet. After high-fat diet with pair-feeding protocol, AdiposeENPP1-TG and WT mice had similar weights. However, AdiposeENPP1-TG mice developed fatty liver in association with changes in AT characterized by smaller adipocyte size and decreased phosphorylation of insulin receptor Tyr1361and Akt Ser473. These changes in AT function and fat distribution were associated with systemic abnormalities of lipid and glucose metabolism, including increased plasma concentrations of fatty acid, triglyceride, plasma glucose, and insulin during IPGTT and decreased glucose suppression during ITT. Thus, our results show that, in the presence of a high-fat diet, ENPP1 overexpression in adipocytes induces fatty liver, hyperlipidemia, and dysglycemia, thus recapitulating key manifestations of the metabolic syndrome.
Resveratrol inhibition of inducible nitric oxide synthase in skeletal muscle involves AMPK but not SIRT1
Authors: Centeno-Baez Carolina , Dallaire Patrice , Marette André
Published: August 2011

The plant-derived polyphenol resveratrol (RSV) modulates life span and metabolism, and it is thought that these effects are largely mediated by activating the deacetylase enzyme SIRT1. However, RSV also activates the cell energy sensor AMP-activated protein kinase (AMPK). We have previously reported that AMPK activators inhibit inducible nitric oxide synthase (iNOS), a key proinflammatory mediator of insulin resistance in endotoxemia and obesity. The aim of this study was to evaluate whether RSV inhibits iNOS induction in insulin target tissues and to determine the role of SIRT1 and AMPK activation in this effect. We found that RSV (40 mg/kg ip) treatment decreased iNOS induction and NO production in skeletal muscle and white adipose tissue, but not in liver, of endotoxin (LPS)-challenged mice. This effect of the polyphenol was recapitulated in vitro, where RSV (10–80 μM) robustly inhibited iNOS protein induction and NO production in cytokine/LPS-treated L6 myocytes and 3T3-L1 adipocytes. However, no effect of RSV was observed on iNOS induction in FAO hepatocytes. Further studies using inhibitors of SIRT1 revealed that the deacetylase enzyme is not involved in RSV action on iNOS. In marked contrast, RSV activates AMPK in L6 myocytes, and blunting its activation using Compound C or RNA interference partly blocked the inhibitory effect of RSV on NO production. These results show that RSV specifically inhibits iNOS induction in muscle through a mechanism involving AMPK but not SIRT1 activation. This anti-inflammatory action of RSV likely contributes to the therapeutic effect of this plant polyphenol.
The Use of Intravitreal Ranibizumab for Choroidal Neovascularization Associated with Vogt-Koyanagi-Harada Syndrome
Authors: Kolomeyer A. M. , Roy M. S. , Chu D. S.
Published: August 2011

Purpose. To describe the use of intravitreal ranibizumab for choroidal neovascular membrane (CNVM) secondary to Vogt-Koyanagi-Harada (VKH) syndrome.Methods. Interventional case report.Results. A 50-year-old woman presented with conjunctival injection and bilateral eye pain. Vision was 20/400 and 20/80 in the right and left eyes, respectively. Bilateral iritis, vitritis, and choroidal thickening were evident. Exudative retinal detachment was present in the left eye. Corticosteroid treatment improved vision to 20/40 bilaterally. Methotrexate (MTX) was initiated and vision remained stable for 3 months. After a 5-month loss to follow-up, vision in the left eye decreased to finger counting (CF) and a parafoveal CNVM was identified. After 3 intravitreal ranibizumab injections, vision improved to 20/40. Twelve months later, despite inflammation control, vision decrease to CF due to recurrent CNVM. A fourth ranibizumab injection was given. Twenty months later, best-corrected vision was 20/400, and an inactive CNVM was present in the left eye.Conclusion. After initial CNVM regression and visual acuity improvement due to ranibizumab, the CNVM recurred and became refractory to treatment. Despite control of inflammation and neovascularization, VKH chronicity lead to permanent vision loss in our patient. A combinational treatment approach may be required in such patients.
Factors Associated with Physician Assistant Practice in Rural and Primary Care in Utah
Authors: Coombs Jennifer M. , Morgan Perri , Pedersen Donald M. , Koduri Sri , Alder Stephen C.
Published: August 2011

Physician Assistants (PAs) have become an integral part of the United States (U.S.) health care system since the profession began in the late 1960s. PAs have been suggested as solutions to predicted physician shortages especially in primary care. This study examined the predictors of primary care and rural practice patterns of PAs in Utah. A cross sectional survey design was utilized. The outcome variables were practice specialty and practice location. The predictor variables were age, gender, number of years in practice, location of upbringing, and professional school of graduation. There was a response rate of 67.7%. The Utah Division of Occupational and Professional Licensing (DOPL) provided the list of licensed PAs in the state. Physician assistants who reported being raised in rural communities were 2.29 times more likely to be practicing in rural communities (95% CI 0.89–5.85). Female PAs had lower odds of practicing in a rural area (OR: 0.26; 95% CI: 0.10–0.66). Female PAs had lower odds of practicing in primary care versus their male counterparts (OR: 0.56; 95% CI: 0.33–0.96). Graduation from the Utah PA Program was more likely to result in primary care practice (OR: 2.16; 95% CI: 1.34–3.49).
Structural and Evolutionary Patterns of Companies in a Financial Distress Situation
Authors: González-Bravo M. I. , Mecaj Arjola
Published: August 2011

The present paper studies the evolution of a set of USA firms during the years 1993–2002. The firms that faced a difficult economic and financial situation in 1993 were considered to be in a distress situation. The aim of this study is to explore if the evolution of this situation depends on the initial features of the distress or if it concerns certain firms' characteristics. If the evolution is independent from the above, the management decisions become crucial in critical times. For the analysis we used a Multidimensional Scaling methodology where the firms are represented in a consensus map according to symptom variables, reaction variables, and recovering variables.
Bayes' Model of the Best-Choice Problem with Disorder
Authors: Mazalov Vladimir , Ivashko Evgeny
Published: August 2011

We consider the best-choice problem with disorder
and imperfect observation. The decision-maker observes sequentially
a known number of i.i.d random variables from a known distribution
with the object of choosing the largest. At the random time the distribution
law of observations is changed. The random variables cannot
be perfectly observed. Each time a random variable is sampled the
decision-maker is informed only whether it is greater than or less than
some level specified by him. The decision-maker can choose at most
one of the observation. The optimal rule is derived in the class of
Bayes' strategies.
Blocking Hypoxia-Induced Autophagy in Tumors Restores Cytotoxic T-Cell Activity and Promotes Regression
Authors: Noman Muhammad Zaeem , Janji Bassam , Kaminska Bozena , Van Moer Kris , Pierson Sandrine , Przanowski Piotr , Buart Stéphanie , Berchem Guy , Romero Pedro , Mami-Chouaib Fathia , Chouaib Salem
Published: August 2011

The relationship between hypoxic stress, autophagy, and specific cell-mediated cytotoxicity remains unknown. This study shows that hypoxia-induced resistance of lung tumor to cytolytic T lymphocyte (CTL)–mediated lysis is associated with autophagy induction in target cells. In turn, this correlates with STAT3 phosphorylation on tyrosine 705 residue (pSTAT3) and HIF-1α accumulation. Inhibition of autophagy by siRNA targeting of either beclin1 or Atg5 resulted in impairment of pSTAT3 and restoration of hypoxic tumor cell susceptibility to CTL-mediated lysis. Furthermore, inhibition of pSTAT3 in hypoxic Atg5 or beclin1-targeted tumor cells was found to be associated with the inhibition Src kinase (pSrc). Autophagy-induced pSTAT3 and pSrc regulation seemed to involve the ubiquitin proteasome system and p62/SQSTM1. In vivo experiments using B16-F10 melanoma tumor cells indicated that depletion of beclin1 resulted in an inhibition of B16-F10 tumor growth and increased tumor apoptosis. Moreover, in vivo inhibition of autophagy by hydroxychloroquine in B16-F10 tumor-bearing mice and mice vaccinated with tyrosinase-related protein-2 peptide dramatically increased tumor growth inhibition. Collectively, this study establishes a novel functional link between hypoxia-induced autophagy and the regulation of antigen-specific T-cell lysis and points to a major role of autophagy in the control of in vivo tumor growth. Cancer Res; 71(18); 5976–86. ©2011 AACR.
Characterization of Operator Learning Curve for Transradial Coronary Interventions
Authors: Ball Warren T. , Sharieff Waseem , Jolly Sanjit S. , Hong Tony , Kutryk Michael J.B. , Graham John J. , Fam Neil P. , Chisholm Robert J. , Cheema Asim N.
Published: August 2011

Background—

Transradial percutaneous coronary intervention (TR-PCI) improves clinical outcomes compared to the transfemoral (TF) approach. However, inadequate training and experience has limited widespread adoption by interventional cardiologists.

Methods and Results—

Clinical and procedural characteristics for TR-PCI were prospectively collected from 1999 to 2008. To identify minimum case volume for optimum clinical benefit, single-vessel TR-PCI cases were chronologically ranked and stratified into 1 to 50, 51 to 100, 101 to 150 and 151 to 300 case volume groups for operators starting the TR approach at the study institution. Cases by operators with a >300 TR-PCI case volume comprised the control group. TR-PCI failure rates, contrast use, guide usage, and fluoroscopy time were compared among groups. A total of 1672 patients underwent TR-PCI by 28 operators. TR-PCI failure occurred in 4% and was higher in the 1 to 50 case volume group compared to the 51 to 100 (
P
=0.007) and control (
P
=0.01) groups. Contrast use was greater in the 1 to 50 group (180±79 mL) compared to the 151 to 300 (157±75 mL,
P
=0.02) and control (168±79 mL,
P
=0.05) groups. Fluoroscopy time was higher in the 1 to 50 group (15±10 minutes) compared to the 101 to 150 (13±10 minutes,
P
=0.04) and control (12±9 minutes,
P
=0.02) groups. Reasons for TR-PCI failure included spasm (38%), subclavian tortuousity (16%), poor guide support (16%), failed access (10%), and radial loop (7%). Case volume was significantly correlated with TR-PCI failure (β=−0.0076,
P
=0.0028), and odds of failure was reduced by 32% for each 50 increments in case volume.

Conclusions—

TR-PCI success depends on operator experience, and a case volume of ≥50 cases is required to achieve outcomes comparable to experienced operators. These findings have implications both for PCI operators looking to expand their skills and for defining standards for training.
Increased Alpha (8–12 Hz) Activity during Slow Wave Sleep as a Marker for the Transition from Implicit Knowledge to Explicit Insight
Authors: Yordanova Juliana , Kolev Vasil , Wagner Ullrich , Born Jan , Verleger Rolf
Published: August 2011

The number reduction task (NRT) allows us to study the transition from implicit knowledge of hidden task regularities to explicit insight into these regularities. To identify sleep-associated neurophysiological indicators of this restructuring of knowledge representations, we measured frequency-specific power of EEG while participants slept during the night between two sessions of the NRT. Alpha (8–12 Hz) EEG power during slow wave sleep (SWS) emerged as a specific marker of the transformation of presleep implicit knowledge to postsleep explicit knowledge (ExK). Beta power during SWS was increased whenever ExK was attained after sleep, irrespective of presleep knowledge. No such EEG predictors of insight were found during Sleep Stage 2 and rapid eye movement sleep. These results support the view that it is neuronal memory reprocessing during sleep, in particular during SWS, that lays the foundations for restructuring those task-related representations in the brain that are necessary for promoting the gain of ExK.
The Bimusical Brain Is Not Two Monomusical Brains in One: Evidence from Musical Affective Processing
Authors: Wong Patrick C. M. , Chan Alice H. D. , Roy Anil , Margulis Elizabeth H.
Published: August 2011

Complex auditory exposures in ambient environments include systems of not only linguistic but also musical sounds. Because musical exposure is often passive, consisting of listening rather than performing, examining listeners without formal musical training allows for the investigation of the effects of passive exposure on our nervous system without active use. Additionally, studying listeners who have exposure to more than one musical system allows for an evaluation of how the brain acquires multiple symbolic and communicative systems. In the present fMRI study, listeners who had been exposed to Western-only (monomusicals) and both Indian and Western musical systems (bimusicals) since childhood and did not have significant formal musical training made tension judgments on Western and Indian music. Significant group by music interactions in temporal and limbic regions were found, with effects predominantly driven by between-music differences in temporal regions in the monomusicals and by between-music differences in limbic regions in the bimusicals. Effective connectivity analysis of this network via structural equation modeling (SEM) showed significant path differences across groups and music conditions, most notably a higher degree of connectivity and larger differentiation between the music conditions within the bimusicals. SEM was also used to examine the relationships among the degree of music exposure, affective responses, and activation in various brain regions. Results revealed a more complex behavioral–neural relationship in the bimusicals, suggesting that affective responses in this group are shaped by multiple behavioral and neural factors. These three lines of evidence suggest a clear differentiation of the effects of the exposure of one versus multiple musical systems.