bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential antidepressants: 3-Aryl-3-(arylthio)propylamines as selective inhibitors of 5-hydroxytryptamine re-uptake in the brain
Authors: Valenta Vladimír , Vlková Marie , Valchář Martin , Dobrovský Karel , Polívka Zdeněk
Published: August 2009

4-(Trifluoromethyl)thiophenol, 2-methylthiophenol, 2-methoxythiophenol, and 1-naphthalenethiol were transformed by reactions with N,N-dimethyl-3-chloro-3-phenylpropylamine to N,N-dimethyl-3-aryl-3-(arylthio)propylamines IVa-VIIa. These afforded the secondary amines IVb-VIIb by treatment with ethyl chloroformate and by the following hydrolysis and decarboxylation of the primarily formed N-(methyl)-N-(ethoxycarbonyl) analogues. Reaction of 1-naphthalenethiol with the 4-toluenesulfonic ester X in situ gave the thiophene analogue VIIIa which was similarly demethylated to VIIIb. Some of the prepared compounds (IVa, IVb, Va, VIIIa)were found to be selective inhibitors of 5-hydroxytryptamine re-uptake in the rat brain synaptosomes which indicates their potential antidepressant activity.
Polar alkaloids from Papaver orientale L.
Authors: Slavík Jiří , Slavíková Leonora
Published: August 2009

Corytuberine (I) and quaternary alkaloids N-methylhebainium hydroxide (II), N-methylisothebainium hydroxide (III), and magnoflorine (IV) as iodides have been isolated for the first time from the fraction of strongly polar alkaloids obtained from aerial parts and roots of Papaver orientale L. The weakly polar fraction contains oripavine, thebaine, isothebaine, and alpinigenine as dominant components. Small amounts of bracteoline, isoboldine, scoulerine, papaverrubines G, A, B, D, and C, and traces of palmatine and coptisine have also been detected.
Kinetics and mechanism of the cytochrome c – sulfite reaction
Authors: Perez-Benito Joaquin F. , Arias Conchita
Published: August 2009

The reaction between the oxidized form of horse-heart cytochrome c and sodium sulfite in aqueous solution has been studied in the pH range 6.5 – 8.2. The reaction is first order in both oxidant and reductant, is accelerated by an increase in pH and is slowed down by addition of potassium chloride. An increase in pH results in an increase in the apparent activation energy (66-77kJ . mol-1). A mechanism in which both HSO3- and SO32- act as reducing agents is proposed, the activation energies corresponding to the cyt c-HSO3- and cyt c-SO32- reactions being 63 ± 4 and 79 ± 2 kJ mol-1, respectively.
Adsorption of ammonia on activated carbon
Authors: Sedláček Zdeněk , Procházková Jitka , Čurda Dušan
Published: August 2009

Adsorption isotherms were measured for ammonia on untreated FB4 activated carbon, FB4 activated carbon impregnated with ZnCl2, and on activated carbon from anti-ammonia filter ( Leipzig, F.R.G.). The potential theory was applied to the measurements. The Dubinin-Radushkevich plot in linearized coordinates for sorbents of the first structural type revealed that the Czechoslovak FB4 activated carbon possesses a bidisperse structure, giving two linear segments in the plot. The sample from the filter, which served as a reference material, exhibited a single straight line in the plot. The measurements were supplemented by the mercury porosimetry determination of the differential distribution curves. The three types of activated carbon were characterized by emission spectral analysis. The characteristic curve enables the equilibrium adsorption to be converted to different pressure and temperature conditions, and thus it is a suitable method for trapping ammonia in freezing stores to protect foods in case of leak of coolant.
Polyhedral organoiridaazaborane chemistry. The preparation of the eleven-vertex nido compound [9-Cl-8-(η5-C5Me5)-nido-8,7-IrNHB9H10] and its characterization by single-crystal X-ray diffraction analysis and nuclear magnetic resonance spectroscopy
Authors: Nestor Karl , Fontaine Xavier L. R. , Kennedy John D. , Štíbr Bohumil , Baše Karel , Thornton-Pett Mark
Published: August 2009

Reaction between nido-6-HNB9H11 (from[9-(MeNC)-arachno-6-HNB9H11] and [(η5-C5Me5).IrCl2]2 in the presence of N,N,N’,N’-tetramethylnaphthalene-1,8-diamine) gives [9-Cl-8-(η5-C5Me5)-nido-8,7-IrNHB9H10] as a yellow crystalline solid in 40% yield. Crystals are triclinic, space group P1, Z = 2, with a = 825.5(1), b = 986.4(2), c = 1 158.7(2) pm, α = 95.12(1), β = 91.00(1), γ = 111.90(1)°. The molecular structure is based on an open-faced nido {IrNB9} eleven-vertex polyhedron with the iridium and nitrogen atoms in adjacent positions in the open face. Nuclear magnetic single and multiple resonance spectroscopy assigns the cluster 11B and 1H resonances, and suggests strong electronic similarities to the sulphur-containing analogue [9-Cl-8-(η5-C5Me5)-nido-8,7-IrSB9H10].
Changes in the standard Gibbs energies associated with the formation of double selenates (NH4)2M(SeO4)2.6H2O (M = Mn, Co, Ni or Zn) and (NH4)2Cd(SeO4)2.2H2O
Authors: Vojtíšek Pavel , Ebert Miroslav , Léblová Markéta
Published: August 2009

The energy changes associated with the formation of double selenates of the schoenite type were studied. By using the Filippov eutonic method, the ΔG° values were obtained directly for the formation of the (NH4)2M(SeO4)2.mH2O salts with M = Mn, Co, Ni, Zn and Cd and m = 6 except for Cd, for which m = 2. The ΔG° values are comparable with those for the analogous potassium salts and they lie within the range of –13.9 to –45.9 kJ mol-l. The fact that the final ΔG° value is primarily affected by the solubilities of the components and of the compound forming was verified for the examined (NH4)2SeO4-MIISeO4-H2O systems as well.
A simple method of estimation of the polydispersity index of narrow molecular weight distributions by using quasielastic light scattering data
Authors: Jakeš Jaromír
Published: August 2009

A simple method of estimation of the polydispersity index of narrow molecular weight distributions using quasielastic light scattering data has been suggested. The method approximates the relaxation times distribution by using the Pearson V distribution and iterates its parameters by the least squares method to an experimental correlation function. For the usual unimodal molecular weight distributions the polydispersity index estimate is good (with an error up to 0.1) at a determined value up to 1.2, rough at a determined value up to 1.5, while above this value the method is virtually impracticable. If the type of the molecular weight distribution is known (Schulz-Zimm, lognormal, Pearson V), the polydispersity value thus determined can be corrected, which would extend the applicability limits of the method. it is shown that for an adequate determination of the polydispersity index the noise level ought to be about 10-4.
Preparation of optically pure enatiomers of Corey lactone by resolution of the racemate
Authors: Žák Bohumil , Veselý Ivan , Neumitka Karel , Paleček Jaroslav
Published: August 2009

Racemic hydrogen butanedioates (IIa, IIb) and hydrogen pentanedioates (IIIa, IIIb), prepared by reaction of racemic Corey alcohols Ia, Ib with the corresponding acid anhydride, were resolved by optically active bases [(1R,2S)-(-)-ephedrine, (S)-(-)-1-phenylethylemine, quinine] to give the optically pure diastereoisomeric salts from which the individual enantiomers of hydrogen butanedioate IIa and IIb and hydrogen pentanedioate IIIa and IIIb were liberated. Acid-catalyzed transesterification with methanol converted these optically pure enantiomers into pure(-)-enantiomer Ia and (+)-enantiomer Ib of the Corey lactone.
Synthesis and properties of 2,5-dimethyl-3-furoylthioureas
Authors: Jurášek Adolf , Badory Viktor , Žvak Vladimír , Štetinová Jarmila
Published: August 2009

Addition of a series of aromatic or aliphatic amines to 2,5-dimethyl-3-furoyl isothiocyanate (I) afforded the corresponding N-(2,5-dimethyl-3-furoyl)-N’-aryl- or alkylthioureas II or III. Spectral data (IR, UV, 1H NMR, 13C NMR and mass spectra) of compounds prepared are presented.
6-(6-Substituted amino-2-hydroxypropyl)-5,6,7,8-tetrahydrodibenz[c, e]azocines
Authors: Szemes Fridrich , Rybár Alfonz , Hrnčiar Pavol , Solčániová Eva , Gattnár Ondrej
Published: August 2009

Nucleophilic addition of alkyl-, cycloalkylamines, or saturated nitrogen-containing heterocycles to isolated or in situ generated 6-(2,3-epoxypropyl)-5,6,7,8-tetrahydrodibenz[c,e]azocine (III) afforded 6-(3-substituted amino-2-hydroxypropyl)-5,6,7,8-tetrahydrodibenz[c,e]azocines IV and their hydrochlorides. The starting 5,6,7,8-tetrahydrodibenz[c,e]azocine (I) reacted with 1-chloro-2,3-epoxypropane to yield 6-(3-chloro-2-hydroxypropyl)-5,6,7,8-tetrahydrodibenz[c,e]azocine (II), which, on treatment with sodium ethoxide or an excess of an amine eliminated hydrogen chloride to give the intermediate III.
Synthesis and application of some new S-(substituted)thio- and thienoquinoline derivatives as antimicrobial agents
Authors: Awad Ibrahim M. A. , Abdel-Rahman Abdu E. , Bakhite Etify A.
Published: August 2009

Ethyl (4-aryl-3-cyano-5,6,7,8-tetrahydro-2-quinolinylthio) acetate (IIa, IIb) were prepared and reacted with hydrazine hydrate to give hydrazines IIIa, IIIb which underwent cyclization into thienoquinoline derivatives IVa, IVb. Reaction of IIIa, IIIb with phenyl isocyanate yielded semicarbazides Va, Vb. Similarly, IIIa, IIIb and IVb were interacted with methyl/phenyl isothiocyanates affording the corresponding thiosemicarbazide derivatives VIa - VId and XIVa, XIVb respectively. On the other hand, condensation of IIIb with acetylacetone gave the pyrazole VII treatment with ethoxide furnished VIII. Also, IIIa, IIIb and IVa, IVb reacted with aromatic aldehydes to afford hydrazones IXa - IXf and XIa - XIf respectively. Cyclodehydration of IXd - IXf with thioglycolic acid furnished 4-thiazolidinone derivatives Xa - Xc. Moreover, IVb was reacted with formic acid/acetic anhydride to give XII and XIII. Diazotization of IVb gave azide XV which underwent Curtius rearrangement into XVI. The structures of all newly synthesized compounds were confirmed by elemental analyses and spectral data. Also, the most of these compounds were tested in vitro for their antimicrobial activities against some Gram-positive and Gram-negative bacteria.
Synthesis and some reactions of cinnoline derivatives
Authors: Youssef Mohamed S. K. , Kamal El-Dean Adel M. , Abbady Mohamed S. , Hassan Khairy M.
Published: August 2009

Article without abstract
Energy dissipation rate in a baffled vessel with pitched blade turbine impeller
Authors: Jaworski Zdzisław , Fořt Ivan
Published: August 2009

Mechanical energy dissipation was investigated in a cylindrical, flat bottomed vessel with four radial baffles and the pitched blade turbine impeller of varied size. This study was based upon the experimental data on the hydrodynamics of the turbulent flow of water in an agitated vessel. They were gained by means of the three-holes Pitot tube technique for three impeller-to-vessel diameter ratio d/D = 1/3, 1/4 and 1/5. The experimental results obtained for two levels below and two levels above the impeller were used in the present study. Radial profiles of the mean velocity components, static and total pressures were presented for one of the levels. Local contribution to the axial transport of the agitated charge and energy was presented. Using the assumption of the axial symmetry of the flow field the volumetric flow rates were determined for the four horizontal cross-sections. Regions of positive and negative values of the total pressure of the liquid were indicated. Energy dissipation rates in various regions of the agitated vessel were estimated in the range from 0.2 to 6.0 of the average value for the whole vessel. Hydraulic impeller efficiency amounting to about 68% was obtained. The mechanical energy transferred by the impellers is dissipated in the following ways: 54% in the space below the impeller, 32% in the impeller region, 14% in the remaining part of the agitated liquid.
Comparison of crystal size in different supersaturation modes
Authors: Hložný Ladislav , Broul Miroslav , Provazník Luděk
Published: August 2009

Crystallization of a solution of ammonium aluminium sulfate dodecahydrate by cooling and by vacuum evaporation was performed in a laboratory batch experiment. In the two crystallization modes, the nucleation was found to proceed at different rates whereas the crystal growth rate did not differ significantly.
Structure of a palladium(II) complex with a non-symmetrical tetradentate Schiff base, [Pd(C14H20N3O)]NCS
Authors: Kratochvíl Bohumil , Ondráček Jan , Maixner Jaroslav , Macíček Josef , Haber Václav
Published: August 2009

The structure of (1-phenyl-3-{2-[(2-aminoethyl)amino]ethylimino}-1-buten-1-olato-O,N,N’,N”) palladium(II) thiocyanate, [Pd(baden)]NCS, was solved by heavy-atom method and refined anisotropically ro R = 0.026 for 2 851 unique observed reflections. The title complex crystallizes in the Pc21b space group with a = 11.919(2), b = 14.061(2), c = 19.769(3)Å, Z = 8. The structure contains two symmetrical-independent molecules, each includes the palladium complex cation and thiocyanate anion. The cation formed by the baden ligand consists of one six-membered and two five-membered chelate rings and the phenyl ring. The coordination polyhedron around palladium is slightly distorted and puckered N3O square. The structure is held predominantly by electrostatic forces, but besides there are weak intermolecular hydrogen bonds among baden and thiocyanate nitrogens.
IR and 13C, 17O, and 119Sn NMR spectra of some bis(1-butyl)tin(IV) carboxylates of dicarboxylic acids
Authors: Holeček Jaroslav , Lyčka Antonín , Nádvorník Milan , Handlíř Karel
Published: August 2009

Infrared spectroscopy and multinuclear (13C, 17O, and 119Sn NMR spectroscopy have been used to study the structure of bis(1-butyl)tin(IV) carboxylates of dicarboxylic acids (1-C4H9)2. Sn(X(COO)2), where X = (CH2)n (n = 0-8), CH=CH (cis and trans) and C6H4 (ortho and para).The crystalline compounds are formed by linear or cyclic oligomers or polymers whose basic building units represent a grouping composed of the central tin atom substituted by two 1-butyl groups and coordinated with both oxygen atoms of two anisobidentate carboxylic groups derived from different molecules of a dicarboxylic acid. The environment of the tin atom has a shape of a trapezoidal bipyramid. When dissolvet in non-coordinating solvents, the compounds retain the oligomeric character with unchanged structure of environment of the central tin atom. In the media of coordinating solvents the bis(1-butyl)tin(IV) carboxylates of dicarboxylic acids form complexes whose central hexacoordinated tin atom binds two molecules of the solvent trough their donor atoms. Carboxylic groups form monodenate linkages in these complexes.
Analogues of the cholecystokinin octapeptide modified in the central part of the molecule
Authors: Hlaváček Jan , Čeřovský Václav , Pírková Jana , Majer Pavel , Maletínská Lenka , Slaninová Jiřina
Published: August 2009

In a series of analogues of the cholecystokinin octapeptide (CCK-8) the amino acid residues were gradually modified by substituting Gly by Pro in position 4, Trp by His in position 5, Met by Cle in position 6, or the Gly residue was inserted between Tyr and Met in positions 2 and 3 of the peptide chain, and in the case of the cholecystokinin heptapeptide (CCK-7) the Met residues were substituted by Nle or Aib. These peptides were investigated from the point of view of their biological potency in the peripheral and central region. From the results of the biological tests it follows that the modifications carried out in these analogues and in their Nα-Boc derivatives mean a suppression of the investigated biological activities by 2-3 orders of magnitude (at a maximum dose of the tested substance of 2 . 10-2 mg per animal).This means that a disturbance of the assumed biologically active conformation of CCK-8, connected with a considerable decrease of the biological potency of the molecule, takes place not only after introduction of the side chain into its centre (substitution of Gly4), but also after the modification of the side chains of the amino acids or by extension of the backbone in further positions around this central amino acid.
Synthesis of three peptides from HLA-A and HLA-B antigens
Authors: Žertová Miroslava , Procházka Zdenko
Published: August 2009

Article without abstract
A new approach to the prediction of gas chromatographic retention indices from physico-chemical constants
Authors: Zenkevich Igor G. , Kuznetsova Lyudmila M.
Published: August 2009

A general approach is proposed to the calculation of gas chromatographic retention indices (RI) of organic compounds on standard polydimethylsiloxane stationary phases based on their principal physico-chemical constants such as the boiling temperature, molar refraction or molecular weight. A combination of logical criteria was established for comparing functions of the above parameters for the identification of substances whose RI values are only determined by their boiling temperatures. It is demonstrated that within homologous series, the dependence of the RI value on the boiling temperature or any additive molecular parameter (molecular weight, molar refraction, number of carbon atoms in the molecule, etc.) is nonlinear. If this dependence is taken into account, the RI value of any organic compound can be predicted with a precision comparable to the standard deviation of the statistically processed values determined in nonequivalent conditions.
Electroreduction of a benzenediazonium salt in the presence of a radical acceptor
Authors: Janderka Pavel , Zábrš Leoš
Published: August 2009

Potentiostatic reduction of p-methoxybenzenediazoniumtetrafluoroborate was studied in acidic aqueous solutions and in dimethylformamide. The mean number of electrons transferred to a molecule of the depolarizer is influenced by the presence of a radical acceptor, acrylamide, and depends on its concentration. The course of electrolysis in the presence of acrylamide was investigated by measuring the relative viscosity of the electrolysed solution. A polymer was isolated from both aqueous and nonaqueous solutions, and its mean relative molecular mass was determined by viscosimetry in an aqueous solution.
Polarographic and voltammetric determination of 1-(2’-carbamoylphenyl)-3,3-dimethyltriazene
Authors: Barek Jiří , Toubar Safa , Zima Jiří
Published: August 2009

A study was carried out of the polarographic behaviour of the genotoxic substance 1-(2’-carbamoylphenyl)-3,3-dimethyltriazene and optimum conditions were found for its determination by tast polarography or differential pulse polarography at a static mercury drop electrode and by fast scan differential pulse voltammetry at a hanging mercury drop electrode in the concentration range 1 . 10-4 -2 . 10-7 mol 1-1. The sensivity of the determination can be further improved through adsorptive accumulation of the test substance on the surface of the hanging mercury drop electrode; five-minute accumulation in unstirred solution permits determination in the concentration range (2-10 . 10-8 mol 1-1 and two-minute accumulation in stirred solution allows determination in the range (2-10) . 10-9 mol 1-1.
Determination of cadmium by electrothermal atomic absorption spectrometry
Authors: Komárek Josef , Slaninová Martina , Vřešťál Jan , Sommer Lumír
Published: August 2009

In the presence of organic compounds, such as EDTA, citric acid or triethanolamine, the absorbance signal of Cd during atomization in a tube of electrographite or covered with pyrolytic graphite appears at a lower temperature than the signal from CdCl2. Some of these compounds, e.g. EDTA, eliminate the interfering effect of NaCl and MgCl2. With urine, however, addition of these compounds often causes splitting of the single absorbance pulse of Cd or an increase of one of the components of a splitted pulse. Addition of a simple modifier HNO3 is therefore recommended for analyses of urine using atomization in a tube of electrographite. The evaluation of the cadmium concentration was done from integrated absorbances by the method of standard additions.
Correlation of substituent – inducted chemical shifts of aromatic protons: Substituted benzonitriles and methyl benzoates
Authors: Exner Otto , Buděšínský Miloš
Published: August 2009

Proton NMR spectra in deuteriochloroform are reported for 53 meta- and para-substituted benzonitriles and 61 methyl benzoates. The substituent-induced chemical shifts (SCS) were correlated with dual substituent parameters (DSP), with 13C SCS of the adjoining carbon, and with the other 1H SCS using the principal component analysis (PCA). They are controlled by different factors in each position to the variable substituent. In the position 4 the long-range polar effects, as expressed by DSP, are decisive, the conjugative component being more important. Remarkable is also very close correlation of 13C and 1H SCS in this position which has no analogy in the other position. In the position 3 there is an additional specific effect of heavier halogens. In the position 2 the short-range effect can be quantified by special constants, only for a subgroup of simple donor substituents it is proportional to DSP. In all positions SCS are practically independent of the second substituent, so that the total chemical shifts can be calculated by an additive scheme. The coupling constants J(2,3), J(5,6), and J(2,6) depend on substitution in the same manner, probably are controlled mainly by substituent electronegativity.
Configurational assignment of aryl heteroaryl ketoximes by means of homonuclear NOE difference spectroscopy
Authors: Heinisch Gottfried , Holzer Wolfgang
Published: August 2009

The utility of homonuclear NOE difference spectroscopy as a simple and rapid method for the configurational assignment of aryl heteroaryl ketoximes is demonstrated employing oximes derived from 4-methoxyphenyl 2-pyrazinyl ketones, (substituted phenyl) 4-pyridazinyl ketones, and benzimidazolyl phenyl ketones.
The synthesis of some monomethylanthraceneamines
Authors: Castle Raymond N. , Kudo Hirotaka , Lee Milton L.
Published: August 2009

The synthesis of 2-methyl-1-anthracenamine (2), 3-methyl-1-anthracenamine (7), 4-methyl-1-anthracenamine (14), 1-methyl-2-anthracenamine (20), 3-methyl-2-anthracenamine (26), and 1-methyl-3-anthracenamine (30) from the corresponding 9,10-anthraquinones in order to confirm their presence in coal-derived products is reported.
Synthesis and analgetic efficiency of some oxy and oxo derivatives of 4(3H)-quinazolinone
Authors: Fišnerová Ludmila , Brunová Bohumila , Kocfeldová Zuzana , Tíkalová Jana , Maturová Eva , Grimová Jaroslava
Published: August 2009

A series of 3-substituted 4(3H)-quinazolinone derivatives have been prepared by alkylation of 4(3H)-quinazolinone with halogenoethers, halogenoketones, and Mannich bases, and the products have been tested for analgetic effects.The most interesting representatives of the oxy and oxo derivatives are 3-[2-(2’,4’-difluoro-4-biphenylyloxy)ethyl]-4(3H)-quinazolinone (Ib) and 3-[2-oxo-2-(4-biphenylyl)ethyl]-4(3H)-quinazolinone (IIi), respectively. Among the group of oxy derivatives also the 2-methylderivative Ig has been prepared, viz. by alkylation of 2’,4’-difluoro-4-hydroxybiphenyl with 2-methyl-3-(2-chloroethyl)-4(3H)-quinazolinone; the activity of Ig is lower than that of Ib.
Potential antihistaminics: Tricyclic carboxylic acids derived from 6,11-dihydrodibenzo[b,e]thiepine and 4,9-dihydrothieno[2,3-c]-2-benzothiepine
Authors: Šindelář Karel , Holoubek Jiří , Svátek Emil , Metyš Jan , Blehová Hana , Polívka Zdeněk
Published: August 2009

Reaction of nitrile IVa with the Grignard’s reagent 1-methyl-4-piperidylmagnesium chloride gave carbinol XIb as product. Carbinols XIa and XIb were dehydrated and hydrolysed with dilute hydrochloric acid to give hydrochlorides of the tricyclic amino acids Vb and Vc. Isomeric compounds with a carboxyl group in position 9 of the tricyclic skeleton were obtained either by hydrolysis of the formely prepared nitrile VIIb (compound VIIIb) or on reaction of bromoketone VIa with 1-methyl-4-piperidylmagnesium chloride, nucleophilic substitution of the bromine atom by the cyano group at the stage of carbinol XIIIb, and subsequent dehydration and hydrolysis of the cyano group, to give amino acid VIIIc. In the first case the synthesis of thiophene analogues XVIIIb and XVIIIc started from ketone XVa, which was brominated with bromine in acetic acid into position 2 of the tricyclic skeleton, followed by Grignard’s reaction with 3-dimethylaminopropylmagnesium chloride in tetrahydrofuran and hydrolysis to bromo derivative XVIb. In the second case derivative XVIc was obtained directly by bromination of hydrochloride XVc. Basic bromo derivatives XVIb and XVIc were reacted with butyllithium in tetrahydrofuran at –60°C to afford corresponding organometallic reagents which, when reacted with solid carbon dioxide, afforded the required amino acids XVIIIb and XVIIIc. Further, some other tricyclic nitriles were synthesized as potential intermediates. The prepared tricyclic amino acids Vb, Vc, VIIIb, VIIIc, XVIIIb and XVIIIc were tested both on animals and in assays of biochemical pharmacology. Some of them displayed considerable antihistaminic activity. The most interesting compound of this series, hydrochloride Vc (VUFB-17689) is a strong antihistaminic with distinctly suppressed sedative effects and it was therefore selected for a more detailed pharmacological testing.
Vapour-liquid equilibria of pyridine + acetate mixtures at 101.325 kPa
Authors: Correa Antonio , Blanco Antonio , Tojo Jose , Correa Jose M. , Arce Alberto
Published: August 2009

Experimental vapour-liquid equilibrium data for the binary mixtures ethyl acetate + pyridine, n-propyl acetate + pyridine and n-butyl acetate + pyridine have been determined at 101.325 kPa. The Wilson, NRTL, LEMF, UNIQUAC and Effective UNIQUAC equations have been fitted to the data, which have also been used to establish UNIFAC parameters for interaction between CCOO and PYRIDINE groups.
Retarding effect of some benzaldehyde derivatives on the dissolution of brass alloy in nitric acid solution
Authors: Assaf Fawzi Hassan , Abou-El-Wafa Moustafa Hassan M.
Published: August 2009

The effect of benzaldehyde and its ortho and para -OH and -OCH3 derivatives on the rate of dissolution of Brass alloy in nitric acid was investigated using thermometric technique. The results were treated by two different methods. It has been found that all compounds act as inhibitors and their effect increases with increasing concentration. The o-OH and o-OCH3 derivatives have the highest inhibition effect.
Catalytic conversion of isopropyl alcohol on pure and alkali doped samarium oxide
Authors: Said Abd El-Aziz Ahmed
Published: August 2009

The catalytic conversion of isopropyl alcohol (IPA) on pure and alkali doped Sm2O3 (10 mole %) was studied in flow system. The reaction is mainly dehydration-dehydrogenation of IPA. The results revealed that, the reaction products are strongly affected by the nature of employed carrier gase. The reaction in oxygen showed the highest activity and selectivity compared to other carriers. The doping process caused a significant decrease in the activity and selectivity of Sm2O3 solids. Probable mechanistic routes for the dehydration and dehydrogenation processes are proposed.
The synthesis of 5-methyl-19-nor-5β-pregna-9,16-diene-3,20-dione, 5-methyl-19-nor-5β-pregna-9,10-diene-3,6,20-trione and their analogues with annellated E ring
Authors: Polman Jiří , Kasal Alexander
Published: August 2009

The synthesis of compounds VII, XVII, XXXIV and XXXVII is described, in which biological activity is assumed. The key steps of their preparation are the dehalogenation of compound XVIII and radicalic deoxygenation of the 6β-hydroxy group in compound XXX, which take place without skeletal rearrangements.
Circularly polarized luminiscence as a probe of metal ions binding sites in calmodulin
Authors: Coruh Nursen , Riehl James P.
Published: August 2009

Circularly polarized luminiscence (CPL) from dilute solutions of Tb(III) bound to the Ca-binding protein calmodulin is reported. The dissymmetry ratio, gem, at 543.5 nm can be monitored as a function of equivalents of metal ion concentration. Competitive and consecutive addition of Ca(II) versus Tb(III) yield results which are consistent with previous results that suggest that Tb(III) and Ca(II) have a preferred affinity for different metal-ion binding sites in this protein.
Ethics and methods in surgical trials
Authors: Ashton C M , Wray N P , Jarman A F , Kolman J M , Wenner D M , Brody B A
Published: August 2009

This paper focuses on invasive therapeutic procedures, defined as procedures requiring the introduction of hands, instruments, or devices into the body via incisions or punctures of the skin or mucous membranes performed with the intent of changing the natural history of a human disease or condition for the better. Ethical and methodological concerns have been expressed about studies designed to evaluate the effects of invasive therapeutic procedures. Can such studies meet the same standards demanded of those, for example, evaluating pharmaceutical agents? This paper describes a research project aimed at examining the interplay and sometimes apparent conflict between ethical standards for human research and standards for methodological rigor in trials of invasive procedures. The paper discusses how the authors plan to develop a set of consensus standards that, if met, would result in substantial and much-needed improvements in the methodological and ethical quality of such trials.
Medical professionalism in the age of online social networking
Authors: Guseh J S , Brendel R W , Brendel D H
Published: August 2009

The rapid emergence and exploding usage of online social networking forums, which are frequented by millions, present clinicians with new ethical and professional challenges. Particularly among a younger generation of physicians and patients, the use of online social networking forums has become widespread. In this article, we discuss ethical challenges facing the patient–doctor relationship as a result of the growing use of online social networking forums. We draw upon one heavily used and highly trafficked forum, Facebook, to illustrate the elements of these online environments and the ethical challenges peculiar to their novel form of exchange. Finally, we present guidelines for clinicians to negotiate responsibly and professionally their possible uses of these social forums.
Nursing in asylum seeker detention in Australia: care, rights and witnessing
Authors: Zion D , Briskman L , Loff B
Published: August 2009

The system of asylum seeker detention in Australia is one in which those seeking refuge are stripped of many of their rights, including the right to health. This presents serious ethical problems for healthcare providers working within this system. In this article we describe asylum seeker detention and analyse the role of nurses. We discuss how far an “ethics of care” and witnessing the suffering of asylum seekers can serve to improve their situation and improve ethical nursing practice.
Philosophy meets disability
Authors: Louhiala P
Published: August 2009

The question “what is disability” and its implications are addressed in a new bookArguing about disability: philosophical perspectives, which aims to fill the gap between disability studies and philosophy. The structure of the book has been organised roughly on the basis of three branches of philosophy: metaphysics, political philosophy and ethics. One of the main themes of the book is the characterisation of athird wayof thinking about disability, a way between two extremes, the medical and social models of disability.
Zinc and Cadmium Transport by the Vertically Migrating Opossum Shrimp, Mysis relicta
Authors: Duyn-Henderson J. A. Van , Lasenby D. C.
Published: August 2009

Mysis feeding on sediments ingested 2–4 times more zinc and 8 times more cadmium than mysids feeding on zooplankton. Mysids feeding on sediments egested 3–5 times more zinc and 5–7 times more cadmium than those feeding on zooplankton. Concentrations of zinc and cadmium were 5–24 times higher in the faecal pellets than in the food. There was little difference in the amount of zinc and cadmium transported upward or downward per mysid. However, 3–4 times more zinc and 4–7 times more cadmium were concentrated and recycled by Mysis at the sediments than in the water column. On a population basis, mysids transported 5 μg Zn and 0.008 μg Cd∙m−3∙night−1 into the water column and 9 μg Zn and 0.020 μg Cd∙m−2∙d−1 to the sediments. It was suggested that mysids and their particulate products (faecal pellets, exuviae) may play an important role in the transport and recycling of cadmium and zinc to other members of the food web.
Functional Regression and Correlation Analysis
Authors: Jensen A. L.
Published: August 2009

In fisheries, many applications of regression analysis are based on functional relations, but application of predictive regression results in two regression equations. Ricker proposed application of a method developed by Teissier to estimate the geometric mean functional relation when the parameters of a functional relation are of biological significance. Functional regression results in a single equation relating variables as opposed to the two equations that result when predictive regression is applied. The geometric mean functional relation also is given by bivariate normal correlation analysis when the correlation coefficient is 1. Bivariate normal correlation analysis provides a model for functional regression. An equation for variation of observed values about the functional regression line is obtained, and functional regression is compared with predictive regression. If the model assumptions are met, the one equation of functional regression is less precise for prediction than the two equations of predictive regression. However, the confidence intervals for the estimates of the slopes for functional and predictive regression are nearly the same.
Apex Predation by Yellowfïn Tuna (Thunnus albacares): Independent Estimates from Gastric Evacuation and Stomach Contents, Bioenergetics, and Cesium Concentrations
Authors: Olson Robert J. , Boggs Christofer H.
Published: August 2009

Three approaches for estimating predation by yellowfin tuna (Thunnus albacares) were compared: (1) stomach analysis adjusted for gastric evacuation; (2) food energy required as a function of swimming speed in yellowfin tracked at sea; and (3) food intake needed to maintain observed cesium concentrations. Gastric evacuation data from captive yellowfin were best fit by linear functions of time for four foods. Fish with high lipid content (mackerel, Scomber japonicus) were evacuated at a slower rate (proportion per hour) than smaller fish (smelt, Hypomesus pretiosus), squid (Loligo opalescens), and small fragile fish (nehu, Stolephorus purpureas), all of which had lower lipid contents. Tuna captured in the eastern Pacific had daily rations averaging 3.9% of body mass based on stomach contents and gastric evacuation rates, 5.2% based on bioenergetics estimates, and 6.7% based on the cesium estimate. Swimming costs accounted for one-third to one-half of the energy budget. Annual predation by the eastern Pacific yellowfin population averaged 4.3–6.4 million metric tons during 1970–72, depending on the method used for estimating ration; 34% was frigate tunas (Auxis spp.). High growth and turnover rates (P/B ratios) of tropical tunas in contrast with low conversion and trophic transfer efficiencies suggest a trophic structure that differs from more productive ecosystems.
Application of Dual-Beam Acoustic Survey Techniques to Limnetic Populations of juvenile Sockeye Salmon (Oncorhynchus nerka)
Authors: Burczynski Janusz J. , Johnson Robert L.
Published: August 2009

Two hydroacoustic surveys of Cultus Lake, British Columbia, were conducted in July 1983 and February 1984 to estimate the size and distribution of the juvenile sockeye salmon (Oncorhynchus nerka) population. The surveys demonstrated the application of a combined dual-beam/echo integration technique for obtaining accurate abundance estimates and other quantitative data. The dual-beam system measured in situ the target strengths (and backscattering cross section) of individual fish. For each survey the mean backscattering cross section of the sampled population was used to scale the integrator outputs to absolute fish density and abundance estimates. Based on previously derived empirical formulas, the mean target strengths compared well with the mean lengths of fish captured by trawl. For this monospecies population with a dominant single-size group of fish, the variance in integrator outputs was due almost entirely to the spatial distribution of fish and not to the variance in measured backscattering cross sections. The confidence intervals of biomass estimates depend on autocorrelation between consecutive acoustic samples, which is related to the spatial distribution of the surveyed population. Trawl catches indicated that about 95% of the fish in the lake were juvenile sockeye salmon. Population estimates made by hydroacoustics were consistent with other available biological data.
ON THE INTRODUCTION OF NEW FLOATING CURRENT CONVEYORS
Authors: SOLIMAN AHMED M. , SAAD RAMY A.
Published: August 2009

Two new types of floating current conveyors are introduced. Each type has four ports: Y, X and two Z ports. The first type is the Floating Second Generation Current Conveyor (FCCII) and includes both CCII+ and CCII- as special cases. The second type is the Floating Inverting Second Generation Current Conveyor (FICCII) and includes both ICCII+ and ICCII- as special cases. The Nodal Admittance Matrix (NAM) stamp for the Nullator-Pathological Current Mirror is derived. Examples are given together with a CMOS circuit realizing both the FCCII and FICCII.
ON THE DVCC AND THE BOCCII AS ADJOINT ELEMENTS
Authors: SOLIMAN AHMED M.
Published: August 2009

The Differential Voltage Current Conveyor (DVCC) with its two polarities namely DVCC- and DVCC+ are reviewed together with their pathological element representations. Their two adjoint building blocks are the Balanced Output Current Conveyor (BOCCII) and the Balanced Output Inverting Current Conveyor (BOICCII) are also discussed with their pathological element representations. The universal CMOS circuit realizing these four building blocks is also included. The Nodal Admittance Matrix (NAM) stamp for the DVCC-, DVCC+, BOCCII and BOICCII are also given. Among the four basic building blocks considered the DVCC- is the only floating building block. Examples are given showing that some of the reported filters are related to each other by the adjoint network theorem.
A NOVEL LOW-VOLTAGE CMOS VARIABLE GAIN AMPLIFIER WITH GAIN-INDEPENDENT INPUT IMPEDANCE MATCHING FOR DTV TUNING APPLICATIONS
Authors: HASAN S. M. REZAUL
Published: August 2009

This paper presents a novel low-voltage single stage CMOS RF Variable Gain Amplifier (RFVGA) designed in 130 nm IBM CMOS process technology using current feed-back gain-independent impedance matching. The proposed RFVGA has a nearly constant gain over the 400 MHz–1 GHz frequency band. Also, it has a 70 dB gain variation (-40 dB to 30 dB) which is decibel-linear within this frequency band for a control voltage in the range of 0.41 V–0.81 V. The RFVGA demonstrates high linearity (THD ≈ -60 dB) and noise immunity (average Noise Figure ≤ 6 dB). It has an input referred third-order intercept point (IIP3) of -1.5 dBm, and an input reflection coefficient (S11) under -8 dB within the frequency band of interest. Also, it dissipates around 5 mW using a 1.2 V power supply. Further, Monte Carlo simulations incorporating process, supply voltage and temperature variations (PVT variations) as well as mismatch between devices (based on width and length of devices) indicate that the design is quite robust. The proposed RFVGA is highly suitable for mobile digital television (DTV) tuner applications.
CONTROLLING CHAOS IN A CHUA'S CIRCUIT USING NOTCH FILTERS
Authors: ZAHER ASHRAF A. , ABU-REZQ ABDULNASSER
Published: August 2009

This paper explores the use of notch filters for the purpose of damping out chaotic oscillations. The design of the filter and the way it is interfaced to the system are investigated from a signal-processing point of view. A Chua's circuit, that has typical applications in synchronization and secure communications, is used to exemplify the suggested methodology where both theoretical and experimental results are provided. The power spectrum of the original system is analyzed to selectively damp-out portions of the power spectrum, thus truncating period-doubling, the original cause of chaos. Both single and double notch filters are explored to examine their effect on the performance of the modified system. Steady state analysis as well as issues regarding practical implementation are addressed and advantages and limitations of the proposed method are highlighted.
Applications of New Sequencing Technologies for Transcriptome Analysis
Authors: Morozova Olena , Hirst Martin , Marra Marco A.
Published: August 2009

Transcriptome analysis has been a key area of biological inquiry for decades. Over the years, research in the field has progressed from candidate gene-based detection of RNAs using Northern blotting to high-throughput expression profiling driven by the advent of microarrays. Next-generation sequencing technologies have revolutionized transcriptomics by providing opportunities for multidimensional examinations of cellular transcriptomes in which high-throughput expression data are obtained at a single-base resolution.
Biased Gene Conversion and the Evolution of Mammalian Genomic Landscapes
Authors: Duret Laurent , Galtier Nicolas
Published: August 2009

Recombination is typically thought of as a symmetrical process resulting in large-scale reciprocal genetic exchanges between homologous chromosomes. Recombination events, however, are also accompanied by short-scale, unidirectional exchanges known as gene conversion in the neighborhood of the initiating double-strand break. A large body of evidence suggests that gene conversion is GC-biased in many eukaryotes, including mammals and human. AT/GC heterozygotes produce more GC- than AT-gametes, thus conferring a population advantage to GC-alleles in high-recombining regions. This apparently unimportant feature of our molecular machinery has major evolutionary consequences. Structurally, GC-biased gene conversion explains the spatial distribution of GC-content in mammalian genomes—the so-called isochore structure. Functionally, GC-biased gene conversion promotes the segregation and fixation of deleterious AT → GC mutations, thus increasing our genomic mutation load. Here we review the recent evidence for a GC-biased gene conversion process in mammals, and its consequences for genomic landscapes, molecular evolution, and human functional genomics.
Genetics, Medicine, and the Plain People
Authors: Strauss Kevin A. , Puffenberger Erik G.
Published: August 2009

The Old Order Amish and Old Order Mennonite populations of Pennsylvania are descended from Swiss Anabaptist immigrants who came to the New World in the early eighteenth century. Today they live in many small endogamous demes across North America. Genetically, these demes have dissimilar allele frequencies and disease spectra owing to unique founders. Biological and social aspects of Old Order communities make them ideal for studies in population genetics and genomic medicine, and over the last 40 years, advances in genomic science coincided with investigational studies in Plain populations. Newer molecular genetic technologies are sufficiently informative, rapid, and flexible to use in a clinical setting, and we have successfully integrated these tools into a rural pediatric practice. Our studies with the Pennsylvania Plain communities show that population-specific genetic knowledge provides a powerful framework in which to prevent disease, reduce medical costs, and create new insights into human biology.
Methods for Genomic Partitioning
Authors: Turner Emily H. , Ng Sarah B. , Nickerson Deborah A. , Shendure Jay
Published: August 2009

The emergence of massively parallel DNA sequencing platforms has made resequencing an affordable approach to study genetic variation. However, the cost of whole genome resequencing remains too high to apply to large numbers of human samples. Genomic partitioning methods allow enrichment for regions of interest at a scale that is matched to the throughput of the new sequencing platforms. We review general categories of methods for genomic partitioning including multiplex PCR, capture-by-circularization, and capture-by-hybridization. Parameters that are relevant to the performance of any given method include multiplexity, specificity, uniformity, input requirements, scalability, and cost. The successful development of genomic partitioning strategies will be key to taking full advantage of massively parallel sequencing, at least until resequencing of complete mammalian genomes becomes widely affordable.
Genetic Screening for Low-Penetrance Variants in Protein-Coding Genes
Authors: Waalen Jill , Beutler Ernest
Published: August 2009

Genetic testing holds great promise as a screening tool to identify persons at risk for a disease at the presymptomatic stage. However, the complexities of gene-disease associations, even in single-gene diseases, pose important challenges. These challenges include defining the role of screening for mutations that have low penetrance, which cause disease in only a minority of patients with the genotype. On the basis of the high rate of false positives, medical expert panels to date have largely discouraged genetic testing for low-penetrance mutations for use in population-based screening, although official recommendations currently exist for only a few genes. We examine the relatively limited experience of population-based screening for low-penetrance mutations in clinical settings to date, including screening for glucose-6-phosphate dehydrogenase deficiency and a low-penetrance mutation for cystic fibrosis in newborns, type 1 Gaucher disease carrier screening, and screening for adults for hemochromatosis. The trend toward recommending restricting use of these tests by medical experts is contrasted with the growing availability of genetic tests, including those for low-penetrance mutations, through direct-to-consumer outlets.
The Toxicogenomic Multiverse: Convergent Recruitment of Proteins Into Animal Venoms
Authors: Fry Bryan G. , Roelants Kim , Champagne Donald E. , Scheib Holger , Tyndall Joel D.A. , King Glenn F. , Nevalainen Timo J. , Norman Janette A. , Lewis Richard J. , Norton Raymond S. , Renjifo Camila , de la Vega Ricardo C. Rodríguez
Published: August 2009

Throughout evolution, numerous proteins have been convergently recruited into the venoms of various animals, including centipedes, cephalopods, cone snails, fish, insects (several independent venom systems), platypus, scorpions, shrews, spiders, toxicoferan reptiles (lizards and snakes), and sea anemones. The protein scaffolds utilized convergently have included AVIT/colipase/prokineticin, CAP, chitinase, cystatin, defensins, hyaluronidase, Kunitz, lectin, lipocalin, natriuretic peptide, peptidase S1, phospholipase A2, sphingomyelinase D, and SPRY. Many of these same venom protein types have also been convergently recruited for use in the hematophagous gland secretions of invertebrates (e.g., fleas, leeches, kissing bugs, mosquitoes, and ticks) and vertebrates (e.g., vampire bats). Here, we discuss a number of overarching structural, functional, and evolutionary generalities of the protein families from which these toxins have been frequently recruited and propose a revised and expanded working definition for venom. Given the large number of striking similarities between the protein compositions of conventional venoms and hematophagous secretions, we argue that the latter should also fall under the same definition.