bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of pH and temperature on the electrical conductivity of membranes made of methacrylic acid copolymers
Authors: Vacík Jiří , Shataeva Larisa K. , Chernova Irina A. , Samsonov Georgii V. , Schauer Jan , Kálal Jaroslav
Published: March 2011

The specific resistance was measured of swollen homogeneous and heterogeneous ion-exchange membranes made of methacrylic acid copolymers with N-(2-hydroxypropyl)methacrylamide and of its copolymers with 2-hydroxyethyl methacrylate. In the case of copolymers of 2-hydroxyethyl methacrylate and methacrylic acid, an increase in the methacrylic acid content raises the specific resistance of the membrane if the carboxylic groups are not ionized. At the degree of neutralization 0.5 the dependence becomes a reverse one. In copolymers of N-(2-hydroxypropyl)methacrylamide with 50 and more per cent of methacrylic acid the specific resistance of the membrane increases with increasing content of methacrylic acid in the case of the nonionized form while remaining virtually unchanged in the ionized form. All the investigated copolymers of N-(2-hydroxypropyl)methacrylamide have a maximum on the curve describing the dependence of the specific resistance on pH. This pH coincides with pH at which the diffusion mobility of the charge carrier of Na+ is highest. The dependence of the specific resistance on temperature can be described in terms of an empirical equation ρT = ρ0e-bT.
29Si, 13C and 1H NMR spectra of some trimethylsiloxy- and bis(trimethylsiloxy)butene isomers
Authors: Schraml Jan , Šraga Ján , Hrnčiar Pavel
Published: March 2011

Three isomers of trimethylsiloxybutene were prepared and identified by 1H NMR spectroscopy to be 2-trimethylsiloxy-1-butene and E and Z 2-trimethylsiloxy-2-butenes. E and Z isomers of 2,3-bis(trimethylsiloxy-2-butene were also prepared. 29Si and 13C chemical shifts in these compounds are interpreted. The shifts indicate that the spatial arrangements in the CH3-C-O-Si(CH3)3 fragment is the same in all the pertinent compounds. Steric crowding forces the trimethylsilyl group to assume conformations in which conjugation between unshared electrons of oxygen atom and the electrons of the double bond is inhibited. As a result, olefinic β carbons are deshielded and the shielding of the silicon is increased.
Synthesis and spectral properties of 4-substituted 2,6-bis-(4-biphenylyl)-3,5-dicyano-1,4-dihydropyridines
Authors: Marchalín Štefan , Kuthan Josef
Published: March 2011

Cyclocondensation of 3-amino-3-(4-biphenylyl)acrylonitrile (Ie) with benzaldehydes p-RC6H4.CHO, 2-furaldehyde and acetone produces 1,4-dihydropyridine derivatives IIa-IIj, III, and IV. 4-Cyanobiphenyl (Id) has been prepared and transformed into nitrile Ie by action of sodium powder and acetonitrile. Relation between structure and spectral properties of the dihydro derivatives prepared is discussed.
The use of 4-R1-benzylidene-4-phenylbenzoylacetonitriles for synthesis of unsymmetrically substituted 3,5-dicyano-1,4-dihydropyridines and 2-amino-4H-pyrans
Authors: Marchalín Štefan , Kuthan Josef
Published: March 2011

3,5-Dicyano-1,4-dihydropyridine derivatives III-V have been prepared by cyclocondensation of benzylidene-4-phenylbenzoylacetonitrile (Ia) with the enamines IIa-IIc. 2-(4-Biphenylyl)-4-(4-R1-phenyl)-6-methyl-3,5-dicyano-1,4-dihydropyridines VI-VIII are formed by condensation of ketonitriles Ib-Id with 3-amino-2-butenenitrile (IIa). Base-catalyzed reaction of compound Ia with enaminonitrile IIa gives the adduct IX which, on dehydration, forms 1,4-dihydropyridine III. 4H-Pyrans X and XI have been prepared by cyclocondensation of the ketonitrile Ia with propanedinitrile and methyl cyanoacetate, respectively.
Mechanism of formation of 2-amino-3-cyano-4,5-diphenylfurane and some of its reactions
Authors: Prousek Josef
Published: March 2011

The reaction of benzoin (I) with propanedinitrile in dimethylformamide catalyzed with diethylamine gives directly 2-amino-3-cyano-4,5-diphenylfurane (III), whereas this reaction catalyzed with glycine in ethanol produces the intermediate II which is transformed into III thermally or by catalysis with diethylamine. The aminofurane III reacts with 4-nitrobenzaldehyde to give azomethine IV, and it produces 2-amino-3-thioamido-4,5-diphenylfurane (V) by reaction with H2S in dimethylformamide.
Liquid-liquid equilibrium. The calculation of composition of coexisting phases in binary systems
Authors: Voňka Petr , Novák Josef P. , Matouš Jaroslav
Published: March 2011

A detailed discussion of convergence of Newton's method employed for calculating the composition of coexisting phases is carried out, and a never-failing-to-converge method is proposed. The procedure is simpler and more reliable than iteration methods of the third order.
Influence of substrate on modified oscillation reactions of the Belousov-Zhabotinskii type
Authors: Ševčík Peter , Adamčíková Ľubica
Published: March 2011

The kinetic parameters of the reaction steps of the oscillation cycle and the parameters of modified oscillation reactions of the Belousov-Zhabotinskii (BZ) type with oxalic acid, tartaric acid, and hypophosphite ions were compared with predictions of Edelson's analysis based on the mechanism of the classical BZ reaction.
cw CO2 laser-induced and SF6-sensitized decomposition of methyl iodide-d3
Authors: Rejnek Jaroslav , Jakoubková Marie , Engst Pavel , Horák Milan
Published: March 2011

The decomposition of CD3I initiated by the irradiation of a cw CO2 laser was studied in the presence of the SF6 sensitizer. The first reaction step of the decomposition produces CD3 radical that yields either methane-d4 (the abstraction reaction of „hot" radicals), or ethane-d6 (the recombination reaction of „cold" radicals). The effect of the total pressure and the composition of the reaction mixture, that of the laser excitation line and output and that of the irradiation time upon the decomposition rate and the product distribution was examined.
Capillary gas-liquid chromatography of pyridine alkyl homologues
Authors: Novrocíková Marta , Novrocík Jan , Vymětal Jan
Published: March 2011

The Kováts retention indices (I) were determined by capillary gas-liquid chromatography on three stationary phases of different polarity, viz. OV-1, Ucon LB-550, and Reoplex 400, for 70 pyridine alkyl homologues present in coal tar. The increments for some alkyl groups were assessed, and the Kováts indices were predicted for 46 pyridine alkyl homologues and compared with the experimental data. The parameters of the linear dependences I(1) = kI(2) + q for pairs of stationary phases (1) and (2) were evaluated.
Studies on copper(I) complexes of some monoaryl thioureas
Authors: Bajpai Anjali , Mishra Deen D. , Bajpai Udai D. N.
Published: March 2011

The copper(I) complexes of o-tolyl-, phenyl-, o-anisyl- and o-chlorophenyl thiourea have been prepared. The IR, NMR and thermal analysis of these complexes has shown that the coordination occurs through the nitrogen atom of the NH2 group except in the case of o-tolyl thiourea complex where it is through the substituted nitrogen atom. The complexes are either monomeric or dimeric in nature.
Routine use of inept technique for measurements of 29Si NMR spectra of trimethylsilyl derivatives
Authors: Schraml Jan
Published: March 2011

Low sensitivity of 29Si NMR, slow 29Si relaxation, and negative Overhauser effect severly limit practical applications of 29Si NMR. The need for the large amount of the sample or of spectrometer time is dramatically reduced if the spectra can be recorded by INEPT technique. It is shown that a standard set of acquisition parameters allows routine measurements of proton decoupled 29Si NMR spectra by INEPT technique in trimethylsilyl derivatives of organic compounds with unknown structure. The INEPT technique makes measurements of 29Si chemical shifts from as litle as 20μmol of compound practical.
Reaction of 30-nor-19(20)-lupene derivatives with bromine
Authors: Klinotová Eva , Klinot Jiří , Protiva Jiří , Urban Jiří , Vystrčil Alois
Published: March 2011

The reaction of 30-nor-19-lupene-3β,28-diol (I) with bromine gives bromo ether III; from the corresponding diacetate II diene IX, unsaturated alcohols VII and VIII and hydroxy ketone XIV were obtained as products of conversion of the primarily formed dibromo derivative VI, depending on the reaction conditions. The structure and configuration of unsaturated alcohols VII and VIII at C(20) is based on 1H and 13C NMR spectra and the different course of their reaction with peracid.
cw CO2 laser photosensitized decomposition of n-heptane
Authors: Pola Josef , Kubát Pavel , Vítek Josef , Farkačová Marta , Trka Antonín
Published: March 2011

CW CO2 laser (the P(34) line, 6.5 W output) induced and SF6 (2.4 kPa)-sensitized decomposition of n-heptane (7.2 kPa) gives mainly ethylene. Propene, butene, ethane and methane are produced as well together with minor amounts of vinylacetylene, 1,3-butadiene, allene, n-butane, 1,4-pentadiene, pentene, and cyclopentadiene. The product distribution corresponds to that obtained in conventional thermolysis of n-heptane performed at temperatures higher than 1 000 °C. The inferences on the size and shape of the hot reaction zone are drawn on the basis of the measurement of temperature profiles in reaction cell.
Selectivities of some hydrogenations on metal-modified platinum catalysts
Authors: Červený Libor , Surma Karel , Růžička Vlastimil , Paseka Ivo
Published: March 2011

The rates and selectivities of hydrogenation on platinum catalysts modified with monolayers of copper, thallium, lead, or bismuth were studied at 20 °C and atmospheric pressure for the competitive hydrogenation of 1-hexene and 1-undecene in cyclohexane and for the consecutive hydrogenation of 1,5-cyclooctadiene in cyclohexane or ethanol. For the former system, the selectivity was unaffected by the modifying metal and the degree of the surface coverage with the metal, and the relative specific hydrogenation rate decreased only slightly with the degree of surface coverage. For the latter system, the selectivity of hydrogenation to cyclooctene increased with the content of the modifying metal, while the relative specific hydrogenation rate decreased markedly.
Preparation and stereochemistry of pentadiene derivatives of furan
Authors: Špirková Katarína , Kováč Jaroslav , Žvak Vladimír , Gracza Tibor , Dandárová Miloslava
Published: March 2011

Synthesis of alkyl 5-(5-X-2-furyl)-3-(2-furyl)-2,4-pentadienoates is described. Their stereochemistry was studied and the UV, IR and 1H NMR spectra interpreted.
Reactions of amidinoyl isothiocyanates with enamines
Authors: Stankovský Štefan
Published: March 2011

Amidinoyl isothiocyanates react with simple enamines II to give derivatives of 1,4-dihydropyrimidine III and amidinoylthioureas IV. Spectral data (IR, UV, 1H NMR) of compounds synthesized are presented.
Multi-chain action of exo-D-galacturonanase from carrot
Authors: Heinrichová Kveta , Perečková Jana
Published: March 2011

Two possible modes of action of exo-D-galacturonanase from carrot (E.C. 3.2.1.67) were investigated; this enzyme catalyses the sequential hydrolytic cleavage of pectants and oligogalacturonans by a terminal action from the nonreducing end of the molecule. The experiments indicate that the investigated exo-D-galacturonanase degrades these substrates by a predominantly multi-chain mechanism. Distribution of degradation products of oligomeric substrates (hexa- and pentagalacturonide) under an optimal condition for the action of the enzyme (pH and temperature) indicates that a multi-chain enzyme attack with a prevalent simple collision is involved. Results of the enzyme degradation kinetics are in a good agreement with the above-mentioned presumption.
Synthesis of some 2,3- and 5,6-unsaturated 19-homosteroids bearing an oxygen containing group at the position 19a
Authors: Kočovský Pavel
Published: March 2011

A synthesis of 5,6- and 2,3-unsaturated 19a-methoxy-19a-homocholestane derivatives XVII and XXI is reported. The key steps in the synthesis of the former compound is protecting the 3β-hydroxyl group and 5,6-double bond by conversion to a cyclosteroid (IX → VI, selective hydroboration of the protected steroid followed by methylation (VI → X → XI) and reductive removal of the 3β-substituent (XVI → XVII). The 2,3-unsaturated methyl ether XXI was obtained by elimination from the mesylate XX prepared from the 5,6-unsaturated derivative XV in three steps.
Synthesis of some unsaturated 19a-homocholestane derivatives
Authors: Kočovský Pavel
Published: March 2011

A synthesis of unsaturated alcohols I, IV-VI is described. The 3,4-unsaturated derivative I was prepared in three steps from the mesylate VIII which by elimination of methanesulfonic acid afforded a mixture of olefins IX yielding two bromo epoxides XII and XIII on treatment with hypobromous acid. Zinc reduction of the compound XIII gave the hydroxy olefin I. In the synthesis of the derivative IV inversion of configuration at C(3) (formally II → IV) was performed in the following manner: reaction of the hypobromous acid with III gave the cyclic ether XV which after saponification and oxidation was converted into the ketone XVIII and the latter was reduced with lithium aluminum hydride to yield a mixture with prepondering equatorial alcohol XX. This compound was acetylated and reduced with zinc to give IV. The 3-epimeric 10β-vinylalcohols V and VI were obtained by reduction of the ketone XXVII.
Competition of 5(O)n and 6(O)n participation by 19a-substituent in hypobromous acid addition to 2,3- and 5,6-unsaturated 19-homocholestane derivatives
Authors: Kočovský Pavel
Published: March 2011

19-Substituted 2,3-unsaturated cholestane derivatives IIIa-IIIc react with hypobromous acid to give the cyclic bromo ether VI as sole or major product arising by cleavage of the 2α,3α-bromoion V with 6(O)n participation by the 19a-group. The 5,6-unsaturated alcohol IVa reacts with hypobromous acid to yield the cyclic bromo ether X as product of 5(O)n participation. Under the same conditions, the methoxy derivative IVb yields two products, X and XI, with violation of Fürst-Plattner rule. In similar manner as in the preceding case, the products arise by cleavage of the bromonium ion IXb with 5(O)n participation by the 19a-methoxyl. In contrast, the 5,6-unsaturated acetoxy derivative IVc reacts without participation via two diastereoisomeric bromonium ions VIIIc and XV to give the corresponding diaxial bromohydrins XVI and XVII which undergo spontaneous cyclization to the epoxides XVIII and XIX. The course of these reactions, comparison with the lower homologs of the type I and II, the role of Markovnikov and Fürst-Plattner rules and capability of the particular functional groups to participate in 5(O)n and 6(O)n processes are discussed.
Neighboring group participation in electrophilic additions: The role of Markovnikov and Fürst-Plattner rule in hypobromous acid addition to 5,6-unsaturated cholestane derivatives
Authors: Kočovský Pavel
Published: March 2011

On reaction with hypobromous acid, the unsaturated alcohol IIIa yields the diequatorial bromo epoxide XIX arising from the 5α,6α-bromonium ion XVIIIa on cleavage at C(5) by 19b-hydroxyl group with 6(O)n participation. By contrast, the bromonium ion XVIIIb generated from the unsaturated methyl ether IIIb is cleaved by water as external nucleophile to yield the unstable diaxial bromohydrin XX which undergoes cyclization to the oxirane derivative XXI. A comparison with the reaction course in homologs of the type I and II permits the conclusion that the change in regioselectivity, generally possible outcome of the 5(O)n participation, is only possible for the 6(O)n process if the participating group is a hydroxyl.
Acetoxyl group as control element in electrophilic addition: Participation by acetoxy group and its competition with other participating groups in hypobromous acid addition to some 5-cholestene derivatives
Authors: Kočovský Pavel
Published: March 2011

The 3β-acetoxy cholestene II (with nonparticipating group at the position 19) is known to be attacked with hypobromous acid predominantly from α-site which results in formation of the diaxial bromohydrin XIV. By contrast, inversion of configuration of the 3-acetoxy group leads to a dramatic change in the reaction course: the 3α-acetoxycholestene derivative VIII is preferentially approached by the electrophile from β-site to give the corresponding 5β,6β-bromonium ion XXVII which on cleavage with 6(O)π,n participation by the 3α-acetoxyl yields two products XXIX and XXXI When hydroxy and acetoxy groups can compete in 5(O)n or 6(O)π,n processes, only hydroxyl group participation takes place (IX → XXV and XI → XXXIV). Two acetoxy groups in X compete successfully in 6(O)π,n processes (X → XXXVII + XLI).
Competition of two participating groups in hypobromous acid addition to some 4-cholestene derivatives
Authors: Kočovský Pavel
Published: March 2011

Hypobromous acid addition to the 4,5-unsaturated hydroxy acetate VIII results in formation of the cyclic bromo ether XXIXa as a product of 5(O)n participation. Participation by hydroxy group is thus preferred over 5(O)π,n process by acetoxyl. Under the same conditions the 4,5-unsaturated diacetate IX afforded the diaxial bromohydrin XXXI arising from 4α,5α-bromonium ion with 5(O)π,n participation by the 3β-acetoxyl whereas an alternative 6(O)π,n participation by the 19-acetoxyl is not operative. The 3-epimeric diacetate XV reacts with hypobromous acid in a more complex way: the molecule is attacked by the electrophile from both α- and β-sites to give two diastereoisomeric bromonium ions XXXII and XXXIII. The former is simply cleaved with water as an external nucleophile to afford the diaxial bromohydrin XXXIV. The latter undergoes fission both with 5(O)π,n and 6(O)π,n participation: The first route leads to the trans-bromohydrin XXXVI. In the second pathway the acyloxonium ion XXXVII postulated as an intermediate is further cleaved with 6(O)π,n participation by 19-acetoxyl to give the acyloxonium ion XXXVIII, which is trapped by water to yield an unusual cis-bromohydrin XXXIX. The differences in the reaction course are discussed.
Peripheral neuropathy: pattern recognition for the pragmatist
Authors: Overell James R
Published: March 2011

Long lists of causes of peripheral neuropathy make peripheral nerve disease a dry and uninspiring subject. A simple scheme based on the answers to just six questions should enable the clinician to recognise characteristic patterns, investigate relevant subgroups appropriately, and identify treatable disorders quickly: which systems are involved? What is the distribution of weakness? What is the nature of the sensory involvement? Is there any evidence of upper motor neuron involvement? What is the temporal evolution? Is there any evidence for a hereditary neuropathy? Standard screening investigations suffice for the common length dependent axonal neuropathies while complex presentations need more detailed investigations targeted to their clinical phenotype.
AFFLECK–DINE LEPTOGENESIS IN THE RADIATIVE NEUTRINO MASS MODEL
Authors: HIGASHI H. , ISHIMA T. , SUEMATSU D.
Published: March 2011

Radiative neutrino mass models have interesting features, which make it possible to relate neutrino masses to the existence of dark matter. However, the explanation of the baryon number asymmetry in the universe seems to be generally difficult as long as we suppose leptogenesis based on the decay of thermal right-handed neutrinos. Since right-handed neutrinos are assumed to have masses of O(1) TeV in these models, they are too small to generate the sufficient lepton number asymmetry. Here we consider Affleck–Dine leptogenesis in a radiative neutrino mass model by using a famous flat direction LHu as an alternative possibility. The constraint on the reheating temperature could be weaker than the ordinary models. The model explains all the origin of the neutrino masses, the dark matter, and also the baryon number asymmetry in the universe.
KÄHLER MODULI INFLATION AND WMAP7
Authors: LEE SUNGGEUN , NAM SOONKEON
Published: March 2011

Inflationary potentials are investigated for specific models in type IIB string theory via flux compactification. As concrete models, we investigate several cases where the internal spaces are weighted projective spaces. The models we consider have two, three, or four Kähler moduli. The Kähler moduli play a role of inflaton fields and we consider the cases where only one of the moduli behaves as the inflaton field. For the cases with more than two moduli, we choose the diagonal basis for the expression of the Calabi–Yau volume, which can be written down as a function of four-cycle. With the combination of multiple moduli, we can express the multi-dimensional problem as an effective one-dimensional problem. In the large volume scenario, the potentials of these three models turn out to be of the same type. By taking the specific limit of the relation between the moduli and the volume, the potentials are reduced to simpler ones which induce inflation. For the case of two Kähler moduli, we exclude the potential as an inflationary model because the moduli might not be stable during inflation. As a toy model, we first consider the simple potential. We calculate the slow roll parameters ϵ, η and ξ for each inflationary potential. Then, we check whether the potentials give reasonable spectral indices ns and their running αs's by comparing with the recently released seven-year WMAP data. For both models, we see reasonable spectral indices for the number of e-folding 47<Ne<61. Conversely, by inserting the observed seven-year WMAP data, we see that the potential of the toy model gives requisite number of e-folds while the potential of the Kähler moduli gives much smaller number of e-folding. Finally, we see that two models do not produce reasonable values of the running of the spectral index.
HAMILTONIAN EMBEDDING OF NONCOMMUTATIVE D-BRANE SYSTEM
Authors: MONEMZADEH M. , TAKI M.
Published: March 2011

We choose the mechanical action of open string in the presence of constant B-fields, which allows us to build up constraint structures. In an open string theory, the secondary constraints give rise to noncommutativity of the string coordinates on the boundaries. We find that applying the Batalin–Fradkin–Fradkina–Tyutin (BFFT) formalism to this noncommutative system converts it to a commutative one and makes new local gauge symmetries.
HEAT CONDUCTION IN 1D FPU DIELECTRIC ATOMIC CHAINS REVISITED
Authors: LI JIN-XING , LIU FEI , CHEN TAO , YI LIN
Published: March 2011

Heat conduction in Fermi–Pasta–Ulam (FPU) dielectric atomic chains were studied by extended FKM formalism. We found that the FPU interactions between atoms have played an important role in quantum thermal transport. For small systems, the numerical simulations indicate that the heat current exhibits a kind of Fourier-like behaviors. In particular, the current is almost unaffected by the massive disorder at the fixed-free boundaries.
SURFACE DAMAGE BEHAVIOR OF GALVANIZED STEEL SHEETS IN FORMING PROCESS UNDER TENSION-BENDING
Authors: YU Z. Q. , HOU Y. K. , LI S. H. , LIN Z. Q. , ZHANG W. G.
Published: March 2011

The surface damage behaviors of different galvanized steel sheets were investigated under the condition of tension-bending. The U-channel forming tests were performed for HDGI (hot-dip galvanized) and HDGA (hot-dip galvannealed) steels. Experimental results indicate that HDGI steel shows better damage resistance than HDGA steel in sheet metal forming. Scratching is the main surface damage in the forming of HDGI steel while exfoliating and scratching of coating are two types of surface damage for HDGA steel. And tool hardness and surface topography have crucial effects on part surface damage in the forming of the two kinds of galvanized steels. Different surface treatments should be applied to the forming tools in the forming of HDGI and HDGA steels for better surface qualities of products.
COMPARATIVE STUDY OF CLINICALLY USED NiTi ORTHODONTIC WIRES
Authors: WANG QIANG , ZHANG YANG , HAO FENGYU , YANG KE , TAN LILI
Published: March 2011

The purpose of the study was to comparatively investigate two NiTi orthodontic wires. It is valuable to determine the phase transformation temperature and corrosion characteristics of the orthodontic wires to further study the shape memory effect and corrosion resistance properties. Optical microscope and EDX analysis were used for microstructure characteristics and composition analysis. Differential scanning calorimetry (DSC) was carried out to identify the phase transformation behavior of the two wires. Electrochemical tests in artificial saliva at 37 ±1°C including polarization and electrochemical impedance spectroscopy (EIS) were used to assess the corrosion resistance and corrosion mechanism of the wires. It was found that the transformation temperature range of A-wire (imported) is narrower while the As and Af are close to the body temperature, which is more suitable in the orthodontic operation at early stage. The corrosion current density of A-wire is lower than that of B-wire (domestically made) while the corrosion potential is higher. EIS test results indicated that the corrosion mechanism was the same. However, the oxide layer formed on the surface of A-wire is more protective.
A NOVEL AND PRECISE TIME DOMAIN DESCRIPTION OF MOSFET LOW FREQUENCY NOISE DUE TO RANDOM TELEGRAPH SIGNALS
Authors: DA SILVA ROBERTO , WIRTH GILSON INACIO , BRUSAMARELLO LUCAS
Published: March 2011

Nowadays, random telegraph signals play an important role in integrated circuit performance variability, leading for instance to failures in memory circuits. This problem is related to the successive captures and emissions of electrons at the many traps stochastically distributed at the silicon–oxide ( S i– S i O 2) interface of MOS transistors. In this paper, we propose a novel analytical and numerical approach to statistically describe the fluctuations of current due to random telegraph signal in time domain. Our results include two distinct situations: when the carrier trap energy state density at the interface is uniform, and when it is an u-shape curve as prescribed in literature, described here as simple quadratic function. We establish formulas for relative error as function of the parameters related to capture and emission probabilities. For a complete analysis, experimental u-shape curves are used and compared with the theoretical aproach.
TRANSPORT ANISOTROPY IN ErNi2B2C ALONG c-AXIS
Authors: LEE W. C.
Published: March 2011

The resistivities along c-axis ρc(H, T) of ErNi 2 B 2 C have been measured with H⊥ and H‖c-axis for 2 < T < 300 K and the superconducting upper critical field Hc2(T) curves of ErNi 2 B 2 C were constructed for each magnetic fields. Our Hc2(T) curves have been compared and discussed with those from ρab(H, T) measurements which explain the anisotropy and its temperature dependence of Hc2(T) are thought to arise from magnetic pair breaking and the anisotropic field dependence of Néel temperature TN originated from Er +3 sublattice.
APPLICATION OF BOUNDARY ELEMENT METHOD FOR 3D WAVE SCATTERING IN CYLINDERS
Authors: BAI H. , SHAH A. H.
Published: March 2011

A boundary element method (BEM) is presented to study 3D wave scattering by cracks in a cylinder. Green's functions needed in the kernel of boundary integral equations in BEM are derived with the help of guided wave functions. Guided wave modes in the cylinder are obtained by a semi-analytical finite element (SAFE) method. Green's functions are constructed numerically by superposition of guided wave modes. In this method, the cylinder is discretized in the radial direction into several coaxial circular cylinders (sub-cylinders) and the radial dependence of the displacement in each sub-cylinder is approximated by quadratic interpolation polynomials. A numerical procedure is used here to accurately calculate the Cauchy's principal value (CPV) and weakly singular integrals. The multi-domain technique is employed here to model the crack surface. Numerical results are presented to show the effectiveness of the proposed solution.
MODELING THERMOPHYSICAL PROPERTIES OF NOBLE GAS INVOLVED MIXTURES
Authors: PAPARI MOHAMMAD MEHDI , MOGHADASI JALIL , NIKMANESH SOUDABEH , HOSSEINI ELHAM , BOUSHEHRI ALI
Published: March 2011

The present work involves in determining isotropic and effective pair potential energy of binary gas mixtures of Kr–Xe , Kr–C2H6 , Xe–C2H6 , Kr–C3H8 , and Xe–C3H8 from thermophysical properties consisting of viscosity and second virial coefficients through inversion method. Typically, the calculated intermolecular potential energy of Kr–Xe system has compared with HFD model potential reported in literature. A desirable harmony between our model potential and HFD model has been obtained. In order to assess the potential energies obtained, transport properties including viscosity, diffusion, thermal diffusion factor, and thermal conductivity of aforementioned mixtures were predicted using the calculated models potential. The deviation percentage of the calculated viscosity and thermal conductivity of above-mentioned mixtures from the literature values are, respectively, within ±2%, ±3%.
Blueshifting of Ion-Implanted InGaAs/InGaAsP Multiple Quantum Well Structures Using Two-Step Rapid Temperature Annealing Process
Authors: Byun Young Tae , Jhon Young-Min , Kim Sun Ho
Published: March 2011

Investigation of implantation-enhanced quantum-well intermixing has been described in a lattice-matched InGaAs/InGaAsP multiple quantum well p–i–n heterostructure. Samples are implanted with a dose of 5 ×1014 P+ ions/cm2 at high energy of 1 MeV. The band gaps in the samples are determined from photoluminescence at room temperature. The rapid thermal annealing (RTA) process is carried out from 675 to 875 °C in intervals 50 °C for 9 min and then the blue-shift of the band gap at 675 °C is as large as 107 nm. However, it is improved to 140 nm when a novel two-step annealing process is conducted at 675 °C (9 min) and 875 °C (1 min) in sequence.
Synthesis of Diamondoids by Supercritical Xenon Discharge Plasma
Authors: Shizuno Tomoki , Miyazoe Hiroyuki , Saito Koya , Stauss Sven , Suzuki Minoru , Sasaki Takehiko , Terashima Kazuo
Published: March 2011

Diamondoids were synthesized by dielectric barrier discharges in supercritical xenon containing dissolved adamantane, which served as a precursor. The synthesis of diamantane was confirmed by gas chromatography mass spectrometry measurements, in addition to energy-dispersive X-ray spectroscopy and micro-Raman spectroscopy measurements. Moreover, the possible synthesis of two higher-order diamondoids, pentamantane and decamantane, with molecular weights of 330 and 456, respectively, is indicated from the selective ion monitoring mode. The largest production yield was obtained in the vicinity of the critical point.
Measurement of Contractile Activity in Small Animal's Digestive Organ by Carbon Nanotube-Based Force Transducer
Authors: Hirata Takamichi , Takeda Naoki , Tsutsui Chihiro , Koike Kanako , Shimatani Yuichi , Sakai Takafumi , Akiya Masahiro , Taguchi Akira
Published: March 2011

A carbon nanotube (CNT)-based force transducer designed to be embedded in the body of a live animal was fabricated and implanted into the stomach of a rat omit to measure contractile movement. The transducer comprised dispersed poly(ethylene glycol)-grafted multiwalled CNTs applied to a comb-like Au-electrode formed on a poly(dimethylsiloxane) sheet. The implanted rat was injected with acetylcholine to induce muscular contractions and changes in the resistance of the transducer were measured. Such changes arise owing to strain in the CNT network upon distortion. The measured resistance change was found to be proportional to the concentration of injected acetylcholine.
From syncitium to regulated pump: a cardiac muscle cellular update
Authors: Korzick Donna H.
Published: March 2011

The primary purpose of this article is to present a basic overview of some key teaching concepts that should be considered for inclusion in an six- to eight-lecture introductory block on the regulation of cardiac performance for graduate students. Within the context of cardiac excitation-contraction coupling, this review incorporates information on Ca2+ microdomains and local control theory, with particular emphasis on the role of Ca2+ sparks as a key regulatory component of ventricular myocyte contraction dynamics. Recent information pertaining to local Ca2+ cycling in sinoatrial nodal cells (SANCs) as a mechanism underlying cardiac automaticity is also presented as part of the recently described coupled-clock pacemaker system. The details of this regulation are emerging; however, the notion that the sequestration and release of Ca2+ from internal stores in SANCs (similar to that observed in ventricular myocytes) regulates the rhythmic excitation of the heart (i.e., membrane ion channels) is an important advancement in this area. The regulatory role of cardiac adrenergic receptors on cardiac rate and function is also included, and fundamental concepts related to intracellular signaling are discussed. An important point of emphasis is that whole organ cardiac dynamics can be traced back to cellular events regulating intracellular Ca2+ homeostasis and, as such, provides an important conceptual framework from which students can begin to think about whole organ physiology in health and disease. Greater synchrony of Ca2+-regulatory mechanisms between ventricular and pacemaker cells should enhance student comprehension of complex regulatory phenomenon in cardiac muscle.
From Claude Bernard to the Batcave and beyond: using Batman as a hook for physiology education
Authors: Zehr E. Paul
Published: March 2011

Communicating physiology to the general public and popularizing science can be tremendously rewarding activities. Providing relevant and compelling points of linkage, however, between the scientific experiences and the interests of the general public can be challenging. One avenue for popularizing science is to link scientific concepts to images, personalities, and icons in popular culture. Currently, comic book superhero movies and television shows are extremely popular, and Batman was used as the vehicle for popularizing concepts of exercise science, neuroscience, and physiology in my recent book, Becoming Batman: the Possibility of a Superhero. The objective of this book was to bring scientific understanding to the broader public by using the physical image and impression everyone has of Batman and his abilities and then connecting this to the underlying science. The objective of this article is to share some of the details of the process and the positive and negative outcomes of using such an approach with other academics who may be interested in similar activities. It is my goal that by sharing this experience I may stimulate like-minded readers to initiate their own similar projects and to also be emboldened to try and integrate popular culture touchstones in their own teaching practice.
Inducible renal principal cell-specific mineralocorticoid receptor gene inactivation in mice
Authors: Ronzaud Caroline , Loffing Johannes , Gretz Norbert , Schütz Günther , Berger Stefan
Published: March 2011

To investigate the role of the mineralocorticoid receptor (MR) in renal ENaC-mediated sodium reabsorption, we have previously used the Cre-loxP system to generate mice with principal-cell specific MR ablation (MRAQP2Cremice). To restrict Cre expression to principal cells, we have used the regulatory elements of the mouse aquaporin-2 (AQP2) gene to drive Cre expression. Since AQP2 is already expressed during renal development, MR ablation took place long before the analysis performed at the adult stage. To investigate whether the early onset of MR ablation affected the adult renal sodium handling, we developed a transgene expressing the CreERT2fusion protein under control of the regulatory elements of the AQP2 gene (AQP2CreERT2). Immunofluorescence revealed MR loss in the collecting duct (CD) and late connecting tubule after induction of MR ablation by tamoxifen in MRAQP2CreERT2mice that equals the MR loss in MRAQP2Cremice. Surprisingly, tamoxifen-independent MR loss is observed in CDs of noninduced mutants without affecting circulating aldosterone levels. Under a low-salt diet, the induced ablation of MR at the adult stage recapitulates the renal sodium wasting observed in mice with constitutive early-onset MR ablation. The AQP2CreERT2transgene is a new tool for investigating in vivo the function of genes downstream of MR in renal ENaC-mediated sodium reabsorption by inducible somatic gene inactivation.
Aqueous Behaviour of Chitosan
Authors: Chattopadhyay D. P. , Inamdar Milind S.
Published: March 2011

Chitosan, a versatile biopolymer, finds numerous applications in textile processing unit operations such as preparation, dyeing, printing, and finishing. However, the accessibility of this biopolymer by the textile material depends on the viscosity of its solution which in turn is a function of its molecular weight. In this work, therefore, the effect of molecular weight, storage life, presence of electrolyte, and particle size of chitosan on its viscosity was investigated. Chitosan of different molecular weights was synthesized by nitrous acid hydrolysis of parent chitosan solution. The synthesized low molecular weight products were analysed by FTIR spectroscopy. Chitosan of nanoconfiguration was prepared by Ionotropic gelation method and characterized by particle size analyzer. The viscosity of different chitosan solutions was determined using Ubbelohde capillary viscometer. As an extension to this study, the chelation property of chitosan was also evaluated.
A Suitable Approach to Estimate Cancer Incidence in Area without Cancer Registry
Authors: Mitton Nicolas , Colonna Marc , Trombert Béatrice , Olive Frédéric , Gomez Frédéric , Iwaz Jean , Polazzi Stéphanie , Schott-Petelaz Anne-Marie , Uhry Zoé , Bossard Nadine , Remontet Laurent
Published: March 2011

Objective. Use of cancer cases from registries and PMSI claims database to estimate Département-specific incidence of four major cancers.Methods. Case extraction used principal diagnosis then surgery codes. PMSI cases/registry cases ratios for 2004 were modelled then Département-specific incidence for 2007 estimated using these ratios and 2007 PMSI cases.Results. For 2007, only colon-rectum and breast cancer estimations were satisfactorily validated for infranational incidence not ovary and kidney cancers. For breast, the estimated national incidence was 50,578 cases and the incidence rate 98.6 cases per 100,000 person per year. For colon-rectum, incidence was 21,172 in men versus 18,327 in women and the incidence rate 38 per 100,000 versus 24.8. For ovary, the estimated incidence was 4,637 and the rate 8.6 per 100,000. For kidney, incidence was 6,775 in men versus 3,273 in women and the rate 13.3 per 100.000 versus 5.2.Conclusion. Incidence estimation using PMSI patient identifiers proved encouraging though still dependent on the assumption of uniform cancer treatments and coding.
Standard Splenic Volume Estimation in North Indian Adult Population: Using 3D Reconstruction of Abdominal CT Scan Images
Authors: Asghar Adil , Agrawal Dushyant , Yunus S. M. , Sharma P. K. , Zaidi S. H. H. , Sinha Aruna
Published: March 2011

A prospective study was carried out to establish normative data for splenic dimensions in North Indian population and their correlation with physical standard on abdominal CT of 21 patients aged between 20 and 70 years having no splenic disorders. Splenic volume was measured by two methods—volume and surface rendering technique of Able 3D doctor software and prolate ellipsoid formula. Volumes measured by both the techniques were correlated with their physical standards. Mean splenic volume was 161.57±90.2 cm3 and range 45.7–271.46 cm3. The volume of spleen had linear correlation with body height (r=0.512, P<.05). Splenic volume (cm3) = 7 × height (cm) − 961 can be used to generate normal standard volume of spleen as a function of body height in North Indian population (with 95% confidence interval). This formula can be used to objectively measure the size of the spleen in adults who have clinically suspected splenomegaly.
On Lower Separation and Regularity Axioms in Fuzzy Topological Spaces
Authors: Saif Amin , Kılıçman Adem
Published: March 2011

We use the concepts of the quasicoincident relation to introduce and investigate some lower separation axioms such as , , , and as well as the regularity axioms and . Further we study some of their properties and the relations among them in the general framework of fuzzy topological spaces.
Association between Levels of C-Reactive Protein and Leukocytes and Cancer: Three Repeated Measurements in the Swedish AMORIS Study
Authors: Van Hemelrijck Mieke , Holmberg Lars , Garmo Hans , Hammar Niklas , Walldius Göran , Binda Elisa , Lambe Mats , Jungner Ingmar
Published: March 2011

Objective: To study levels of C-reactive protein (CRP) and leukocytes, as inflammatory markers, in the context of cancer risk.

Methods: From the Apolipoprotein MOrtality RISk (AMORIS) study, we selected 102,749 persons with one measurement and 9,273 persons with three repeated measurements of CRP and leukocytes. Multivariate Cox proportional hazards regression was applied to categories of CRP (<10, 10–15, 15–25, 25–50, >50 g/L) and quartiles of leukocytes. An inflammation-based predictive score (IPS) indicated whether someone had CRP levels of more than 10 mg/L combined with leukocytes of more than 10 × 109/L. Reverse causality was assessed by excluding those with less than 3, 5, or 7 years of follow-up. To analyze repeated measurements of CRP and leukocytes, the repeated IPS (IPSr) was calculated by adding the IPS of each measurement.

Results: In the cohort with one measurement, there was a positive trend between CRP and risk of developing cancer, with the lowest category being the 0.99 (0.92–1.06), 1.28 (1.11–1.47), 1.27 (1.09–1.49), and 1.22 (1.01–1.48) for the second to fifth categories, respectively. This association disappeared when excluding those with follow-up of less than 3, 5, or 7 years. The association between leukocytes and cancer was slightly stronger. In the cohort with repeated measurements, the IPSr was strongly associated with cancer risk: 1.87 (1.33–2.63), 1.51 (0.56–4.06), and 4.46 (1.43–13.87) for IPSr = 1, 2, and 3 compared with IPSr = 0. The association remained after excluding those with follow-up of less than 1 year.

Conclusions and Impact: Our large, prospective cohort study adds evidence for a link between inflammatory markers and cancer risk by using repeated measurements and ascertaining reverse causality. Cancer Epidemiol Biomarkers Prev; 20(3); 428–37. ©2011 AACR.
Antitumor Activity of the Hsp90 Inhibitor IPI-504 in HER2-Positive Trastuzumab-Resistant Breast Cancer
Authors: Scaltriti Maurizio , Serra Violeta , Normant Emmanuel , Guzman Marta , Rodriguez Olga , Lim Alice R. , Slocum Kelly L. , West Kip A. , Rodriguez Varenka , Prudkin Ludmila , Jimenez José , Aura Claudia , Baselga José
Published: March 2011

Hsp90 facilitates the maturation and stability of numerous oncoproteins, including HER2. The aim of this study was to assess the antitumor activity of the Hsp90 inhibitor IPI-504 in trastuzumab-resistant, HER2-overexpressing breast cancer cells. Therapy with trastuzumab, IPI-504, and the combination of trastuzumab and IPI-504 was evaluated in trastuzumab-sensitive and trastuzumab-resistant cells. Inhibition of protein targets, cell proliferation, and tumor growth was assessed in vitro and in xenograft models. IPI-504 inhibited proliferation of both trastuzumab-sensitive and trastuzumab-resistant cells. Administration of IPI-504 markedly reduced total levels of HER2 and Akt, as well as phosphorylated Akt and mitogen-activated protein kinase (MAPK), to an equal extent in trastuzumab-sensitive and trastuzumab-resistant cells. IPI-504, used as single agent or in combination with trastuzumab, also inhibited in vivo the growth of both trastuzumab-sensitive and -resistant tumor xenografts. As a mechanism for the observed antitumor activity, IPI-504 resulted in a marked decrease in the levels of HER2, Akt, p-Akt, and p-MAPK in trastuzumab-resistant xenografts as early as 12 hours after a single dose of IPI-504. IPI-504–mediated Hsp90 inhibition may represent a novel therapeutic approach in trastuzumab refractory HER2-positive breast cancer. Mol Cancer Ther; 10(5); 817–24. ©2011 AACR.
A Randomized Controlled Trial of Cognitive Behavioral Group Therapy for Bipolar Disorder
Authors: Gomes B.C. , Abreu L.N. , Brietzke E. , Caetano S.C. , Kleinman A. , Nery F.G. , Lafer B.
Published: March 2011

Background: This study evaluated the effectiveness of adjunctive cognitive behavioral group therapy (CBGT) to prevent recurrence of episodes in euthymic patients with bipolar disorder. Methods: A randomized controlled single-blind trial was conducted with 50 patients with bipolar disorder types I and II followed up for at least 12 months in an outpatient service and whose disease was in remission. An experimental CBGT manual was developed and added to treatment as usual (TAU), and results were compared with TAU alone. Results: Intention-to-treat analysis showed that there was no difference between groups in terms of time until any relapse (Wilcoxon = 0.667; p = 0.414). When considering type of relapse, there was still no difference in either depressive (Wilcoxon = 3.328; p = 0.068) or manic episodes (Wilcoxon = 1.498; p = 0.221). Although occurrence of episodes also did not differ between groups (χ2 = 0.28; p = 0.59), median time to relapse was longer for patients treated with CBGT compared to TAU (Mann-Whitney = –2.554; p = 0.011). Conclusions: Time to recurrence and number of episodes were not different in the group of patients treated with CBGT. However, median time to relapse was shorter in the TAU group. Studies with larger samples may help to clarify whether our CBGT approach prevents new episodes of bipolar disorder. Our findings also indicated that CBGT is feasible in euthymic patients with bipolar disorder and should be investigated in future studies. To our knowledge, this is the first publication of a controlled trial of CBGT for euthymic patients with bipolar disorder.
A Practice-Based Comparison of Brief Cognitive Behavioural Treatment, Two Kinds of Hypnosis and General Anaesthesia in Dental Phobia
Authors: Wannemueller André , Joehren Peter , Haug Simon , Hatting Mathias , Elsesser Karin , Sartory Gudrun
Published: March 2011

Background: A practice-based study was carried out to assess the comparative effectiveness and acceptability of standardised hypnosis, hypnosis with individualised imagery, cognitive behavioural treatment (CBT) and general anaesthesia (GA) in the treatment of dental phobia. Methods: A 4-group design was used with 4 repeated measurement occasions. Of an initial total of 137 dental phobics, 77 completed the study with sample sizes of between 14 and 29 patients in the 4 groups. Participants completed questionnaires of dental anxiety at the beginning of the trial, before and after the first dental appointment and again before the second dental appointment a week later. Results: Standardised hypnosis evidenced a significantly higher rate of premature termination of treatment than CBT. The completer analysis showed a significant reduction of dental anxiety after CBT and individualised hypnosis compared to the GA condition. The intent-to-treat analysis showed significant improvement only after CBT. Conclusions: The results suggest that CBT is the treatment of choice in dental phobia when taking both effectiveness and acceptability into account.