bluuebunny/crossref_metadata_2025 huggingface dataset:
Preferential tritium labelling of binding site residues in alpha chymotrypsin by exposure of the 1,3‐3H‐diisopropylphosphoryl derivative to tritiated hydrogen sulfide
Authors: White Frederick H.
Published: October 2006

When alpha chymotrypsin, labelled with a heavily tritiated diisopropylphosphoryl (3HDIP) group on the serine residue at position 195, was exposed to tritiated hydrogen sulfide (3HSH) under dry conditions, an incorporation of 3H occurred that favored residues close to the binding site. The reaction mechanism remains unclear. A direct transfer of 3H from the ligand is ruled out, although 3H in this position as well as in 3HSH is essential for the labelling reaction. It is shown that the reaction does not involve self‐radiolysis. It is suggested that the reaction may instead be related to an observed instability of 3H within the ligand, possibly through a free radical mechanism.
Synthesis of 2,4‐dihydroxy‐6‐pentyl‐benzoic‐6‐14C acid, ethyl ester. (olivetolic‐6‐14C acid. ethyl ester)
Authors: Schmit J. P. , Van de Velde V. , Piraux M.
Published: October 2006

In a first step, Δ1‐trans‐octenoic‐3‐14C acid was prepared by a Grignard reaction with BaCO3‐14C and 1‐bromo‐pentane, followed by reduction of the obtained hexanoic‐1‐14C acid to hexanal‐1‐14C via the n‐hexanol‐1‐14C. The produced hexanal‐1‐14C, by condensing with malonic acid gives the request Δ1‐trans‐octenoic‐3‐14C acid. In a second step, olivetolic‐6‐14C acid, ethyl ester was prepared by condensing the Δ1‐trans‐octenoic‐3‐14C acid, methyl ester with ethyl acetoacetate followed by bromination and catalytic hydrogenation.
Synthesis of 14C‐labelled isotope‐isomeric alkanes. I n‐heptane‐1‐14C and ‐2‐14C
Authors: Bally Ioana , Gǎrd Eugenia , Ciornei Elieabeta , Biltz Maria , Balaban A. T.
Published: October 2006

The synthesis of n‐heptane‐1‐14C is described. starting from 14CH3I via (14CH3) 2Cd and caproyl chloride; for obtaining n‐heptane‐2‐14C, n‐pentyl bromide is converted into the Grignard reagent, carbonated with 14CO2, and the resulted coproic acid is converted into its chloride and treated with dimethyloadmium. In both cases the labelled n‐heptan‐2‐one is finally reduced to labelled n‐heptane by the Kishner‐Wolff method.
A major impurity in 3H‐17α‐hydroxypregnenolone
Authors: Shapiro Martin I. , Bhavnani Bhagu R.
Published: October 2006

Evidence of a major impurity in commercially available 3H‐17α‐hydroxypregnenolone is presented.
Preparation of tritium‐labeled compounds. V. A group of steroids by catalytic reduction of unsaturated precursors with tritium gas
Authors: Thomas Richard C. , Ikeda George J. , Campbell J. Allan , Harpootlian Harry
Published: October 2006

A group of Δ4‐3‐keto steroids was prepared by catalytic reduction of suitable conjugated diene‐3‐keto precursors with tritium gas. Thus, 11α‐hydroxy‐4‐pregnene‐3,20‐dione‐7‐3H (I), 20α‐hydroxy‐4‐pregnen‐3‐one‐7‐3H (II), 6α‐methyl‐4‐pregnene‐3,11,20‐trione‐7‐3H (III), 17α‐hydroxy‐6α‐methyl‐4‐pregnene‐3,20‐dione‐7‐3H, acetate (IV), and 17α‐hydroxy‐6‐methyl‐3H3‐16‐methylenepregna‐4, 6‐diene‐3,20‐dione, acetate (V) were prepared from 11α‐hydroxypregna‐4,6‐diene‐3,20‐dione (VI), 20α‐hydroxypregna‐4,6‐dien‐3‐one (VII), 6‐methylpregna‐4,6‐diene‐3,11,20‐trione (VIII), 17α‐hydroxy‐6‐methylpregna‐4,6‐diene‐3,20‐dione, acetate (IX), and 17α‐hydroxy‐6‐dibromomethylene‐16‐methylene‐4‐pregnene‐3,20‐dione, acetate (X), respectively. In addition, 3α‐hydroxy‐5β‐pregnane‐11,20‐dione‐7‐3H, cyclic 20‐(trimethylene acetal) (XI) was prepared from I via 11α‐hydroxy‐5β‐pregnane‐3,20‐dione‐7‐3H (XII), 5β‐pregnane‐3,11,20‐trione‐7‐3H (XIII) and 3α‐pregnane‐11,20‐dione‐7‐3H (XIV).
Improved techniques for semi‐micro synthesis of radioisotope labelled thiophosphate pesticides
Authors: Smith B. R. , Dauterman W. C. , Hodgson E.
Published: October 2006

Radiolabelled ethanol can be incorporated into the organophosphate molecule by heating PSCl3 with the labelled alcohol. Methanol can also be incorporated in this manner, but with lower yields. The O, O‐dialkyl, phosphorochloridothionates were produced by treating O‐alkyl phosphorodiahloridothionate with the appropriate sodium alkoxide. Coupling the O, O‐dialkyl phosphorochloridothionate to a substituted phenol to form the pesticidal compounds was facilitated by the catalytic effect of silver ions. The catalyzed coupling reaction was found to be compatible with hdroxyllated heterocyclic compounds, and with phenols containing nitro‐, mercapto‐, alkyl‐, and cyano‐substituents. The reaction was not successful, however, with chloro‐substituted phenols The coupling reaction was also found to be useful in synthesizing EPN, a phosphonothionate pesticide. The coupling reaction does not appear to be useful for the synthesis of oxons, the analogous phosphate compounds.
The preparation of 3‐acetamido‐6‐methyl‐8‐N‐propyl‐S‐[3‐14C] triazolo‐[4, 3‐a] pyrazine [I.C.I. 58,301]
Authors: White D. F. , Burns J.
Published: October 2006

The preparation of 3‐acetamido‐6‐methyl‐8‐n‐propyl‐s‐[3‐14C] triazolo‐[4, 3‐a] pyrazine [I.C.I. 58,301] from sodium [14C] cyanide in three stages is described. The overall radiochemical yield of product, at a specific activity of 3.6 μCi/mg, was 26.0%.
Labelling of steroios by exchange with isotopic water on heterogeneous platinum and palladium: Methods for overcoming competing oxidation
Authors: Garnett J. L. , O'Keefe J. H.
Published: October 2006

A representative group of steroids have been labelled by exchange with isotopic water in the presence of heterogeneous Group VIII transition metals. Platinum and palladium are the best of the metals studied. Steroids examined included oestrogens, keto and hydroxy derivatives, hydrocarbons and two cardiac glycosides. The presence of an OH group in the steroid leads to oxidation simultaneously with isotope incorporation. Esterification of the OH group prior to exchange eliminates oxidation and yields labelled compounds of high chemical purity. The variables affecting optimum exchange have been determined and include solvent, temperature of reaction and method of catalyst activation. Isotope orientation in the labelled steroids supports a mechanism involving the role of π‐ and σ‐bonded intermediates in the exchange reaction.
Isotopic hydrogen labelling of steroids by homogeneous platinum catalysed exchange
Authors: Garnett J. L. , O'Keefe J. H.
Published: October 2006

A number of new homogeneous metal catalysts have been studied for the deuteration and/or tritiation of a range of steroids. Sodium tetrachloropltinate (II) was the most satisfaatory of the catalysts examined. This aompound catalysed selective exchange of protons in ring A of aromatic type steroids such as 3‐desoxyestrone. oestrone and oestradiol. Conversion of the free steroids to their acetate or benzoate esters gave better labelling since the OH group in the free steroid reacts with the catalyst leading to precipitation of platinum from the homogeneous solution and a reduction in exchange rate. Steroids with hindered double bonds such as cholesterol, testosterone, pregnenolone, desoxycorticosterone acetate and progesterone do not exchange rapidly nor do the cardiac glycosides, digitoxin and digitoxigenin. Exchange with homogeneous platinum is more selective in isotope incorporation than with the corresponding heterogeneous platinum. A mechanism for the homogeneous exchange is proposed in terms of π‐bonded intermediates. The present data are a guide for predicting the isotopic hydrogen labelling behaviour of steroids with the recently discovered homogeneous platinum catalyst.
Marquage par 125I et 14C d'Indomonocarbocyanines a Tropisme Hepatique
Authors: Moreau Marie‐France , Lapalus Françoise
Published: October 2006

The 125I and 14C labelling of new dyes for the functional hepatic exploration, are described.
Microsynthesis of 3H‐sterculic acid with high specific activity
Authors: van Tilborg H.
Published: October 2006

Copper‐catalysed addition of ethyl diazoacetate to methyl scearolate (20 mmol scale) and subsequent saponification gave 9, 10‐carboxymethylene, 9‐octadecenoic acid in 67% yield. The letter was decarbonylated by treatment with HClO4/Ac2O in the cold (76 μmol scale) to give cyclopropenium perchlorate, which was reduced with NaBH4. After removal of non‐acidic by‐products. sterculic acid labelled with 3H in the cyclopropene ring was obtained in 9% yield. Its specific activity was 140 mCi/mmol, the radiochemical purity was 90%.
Syntheses with stable isotopes: Sodium cyanide‐13C
Authors: Whaley Thomas W. , Ott Donald G.
Published: October 2006

Sodium cyanide‐ 13C has been prepared in 65–70% overall yield from carbon‐13C monoxide in a three‐step synthesis proceeding through isopropyl formate‐ 13C and formamide‐ 13C as intermediates. Several. methods for the dehydration of formamide have been investigated.
Preparation of 3H‐ and 14C‐labelled contraceptive steroids
Authors: Shibata Kenyu , Osawa Yoshio , Sandberg Avery A.
Published: October 2006

3H‐ and 14C‐Labelled ethynodiol diacetate, chlormadinone acetate, and medroxyprogesterone acetate with one label at the steroid nucleus and the other at the acetoxy group were prepared for use in studies of regio‐ and stereospecificity of metabolic hydrolysis of the steroid contraceptives. Steroidal secondary, tertiary, equatorial, and axial acetates were labelled under selective conditions using acetic anhydride.
Synthesis of 2,3‐bis(p‐methoxyphenyl) indole‐2‐14C
Authors: Thomas Richard C.
Published: October 2006

2,3‐Bis(p‐methoxyphenyl)indole‐2‐14C was prepared at a specific activity of 1.71 mCi/mM from Ba14CO3 by a 4‐step synthetic sequence in 23% overall radiochemical yield.
Synthesis of 1,2‐3H‐oeoxycorticosterone azidoformate
Authors: Burrows Elizabeth P. , Nsergaard Jon R. , Smith Howard E.
Published: October 2006

An efficient synthesis of 1,2‐3H‐deoxycorticosterone azido‐formate from 1,2‐3H‐deoxyaorticorterone via the chloroformate, adaptable to microgram quantities, is described.
Synthesis of a tumor‐growth inhibitor‐dihydrochloride of 1‐nitro‐9‐/dimethylamino‐propylamino/‐acridine/C‐283/tritium labelled in the acridine ring and 14C‐labelled in the side chain
Authors: Kołodziejczyk A. , Arendt A.
Published: October 2006

1‐Nitro‐9/dimethylaminopropylamino/‐acridine dihydro‐chloride /C‐283, ‘Ledaarin’/ is used as an anti‐twnor drug, In view of the studies on its mechanism of action. the syntheses of two specimens of this compound labelled with radioisotopes have been carried out. One of them contained C14 in the side chain and the other tritiwn in the acridine ring. 3‐Dimethylaminopropylamine /1‐C14/ prepared on the basis of K14 was used as the initial substrate for the synthesis of C‐283 labelled with 14C. It was condensed with pyridinium salt of 1‐nitro‐9‐chloroacridine.

In order to introduce tritium to the acridine ring, m‐nitro‐aniline was tritiated in the aaidia solution of tritiated water.

Thus obtained tritiated m‐nitroaniline was condensed by Ullman's method with o‐ahlorobenzoia acid.

The N‐/3′‐nitrophenyl/anthranilia acid was then converted to the derivative of 1‐nitro‐9‐chloroacridine /2,3,4‐T3/. The specific activity of C‐283 14C labelled was 5.5 mCi/mmole and that of C‐283 tritium labelled 103 mCi/mmole.
Synthesis of 3H‐etomidate ano resolution into its enantiomers
Authors: Heykants J. J. P. , Knaeps A. G. , Janssen M. A. C.
Published: October 2006

Etomidate, (R)‐(+)‐ethyl 1‐(1‐phenylethyl)‐1H‐inidazole‐5‐carboxylate, is a short‐acting hypnotic. Tritium was introduced in the ortho‐position of the phenyl‐group by catalytic dehalogenation of the 2‐chloro‐analogue. The homologous tritiated methyester, (+)‐methyl 1‐(1‐phenylethyl)‐1H‐imidazole‐5‐carboxylate, was hydrolyzed to the corresponding carboxylic acid. The resolution into both enantiomers was carried out by successive salt formation with (R)‐(+)‐ and (S)‐(‐)‐α‐methylbenzenemethanamine. After isolation of the diastereoisomeric salts, both enantiomers were obtained by esterification of the salts in ethanol, saturated with HCl‐gas.
Synthese von 15N‐Markierten 2‐Substituierten 2‐Thiazolinen und Analogen Thiazinen
Authors: Volford J. , Bànfi D.
Published: October 2006

Zur Untersuahung der Tautomerie des 2‐Phenylamino‐2‐thiaaolins und des analogen 1.3‐Thiaains wurde die selektive 15N‐Markierung des exo‐ bzw. endo‐Stiakstoffatomes dieser Verbindungen durahgeführt. Der Isotopeneffekt der markierten Verbindungen konnte IR‐spektroskopisah registriert werden.
Synthesis of a new adrenal cortex imaging agent 6β‐131 I‐iodomethyl‐19‐nor cholest ‐5(10)‐en‐3β‐ol (NP‐59)
Authors: Basmadjian Garabed P. , Hetzel Kenneth R. , Ice Rodney D. , Beierwaltes William H.
Published: October 2006

A new adrenal cortex imaging agent. 6β‐131 I‐iodomethyl‐19‐norcholest‐5(10)‐en‐3β‐ol (NP‐59)[I] was synthesized by the homallylic rearrangement of 19‐iodocholesterol or directly from cholest‐5‐ene‐3β, 19‐diol‐19‐toluene‐p‐sulfonate via homoallylic rearrangement with the iodide ion as a nucleophile and subsequent exchange with Na131I. NP‐59 appears to concentrate 5 times better than 19‐iodocholesterol in the rat adrenal and is currently being evaluated as a possible diagnostic agent in man.
General methods for the preparation of deuterium and tritium‐labelled phenethylamines and phenethanollamines: Synthesis of radioactive 6‐hydroxydopamine
Authors: Rotman A. , Daly J. W. , Creveling C. R.
Published: October 2006

A convenient synthetic method for preparation of phenethylamines and phenethanolamines labeled with deuterium or tritium has been developed. A substituted benzaldedyde is condensed with nitromethane or nitroethane and the resultant nitrostyrene is reduced with sodium borotritide or borodeuteride. Subsequent reduction of the nitro‐group and removal of blocking groups yields a phenethylamine or an a‐methylphenethylamine containing a tritium or deuterium in the benzylic position. Condensation of the substituted benzaldehyde with nitromethane or nitroethane at low temperature yields a nitroalcohol which is oxidized to a ketone with Jones reagent. Reduction with sodium borotritide or borodeuteride and subsequent reduation of the nitro‐group and removal of blocking groups yields a phenethanolamine or α‐methylphenethanolamine labeled in the bensylic position. Preparation of deutero‐ and/or tritio‐labeled 2,4,5‐trihydroxyphenethylamine (6‐hydroxydopamine). α‐methyl‐6‐hydroxydopamine, α‐methyl‐p‐tyramine, β‐phenethanolamine. 2‐hydroxyphenethanolamine and α‐methyl‐4‐benzyloxyphenethanolamine is described.
Radiolysis of 14C‐ and 3H‐labelled thymidine
Authors: Kopoldová J. , Dedkǒvá V.
Published: October 2006

10−3M oxygenated aqueous solutions of thymidine preparations, labelled with 14C and 3H in various positions were gammairradiated. Radiation produats formed were followed in dependenae of irradiation doses. Their yields were confronted with produats formed during the autoradiolysis of long time stored tritiated thymidine preparations, and results obtained Were disaussed.
The synthesis and purification of 8‐14C‐theophylline
Authors: Lohmann Suzanne M. , Miech Ralph P.
Published: October 2006

The enzymes responsible for the metabolism of methylated xanthines suah as theophylline, theobromine, and caffeine have until now escaped identification (1, 2). However, a sensitive radiometric method of analysis of theophylline metabolism (3) was made possible by the synthesis and purification of 8‐14C‐theophylline (14C‐Theo). 14C‐Theo was synthesized by the incorporation of 14C from 14C‐formic acid into the 8‐position of the purine ring. Purification of the 14C‐Theo was accomplished by subjecting the crude produot to cation‐exchange column chromatography with AG50W‐X12, 50–100 mesh resin of the hydrogen ion form.
Preparation du phenyl‐3 propene‐2 OL‐1 14C‐3 (alcool cinnamique 14C‐3)
Authors: Nguyen‐Hoang‐Nam  , Hoellinger H. , Pichat L.
Published: October 2006

Methyl cinnamate ‐3‐14C is reduced smoothly in excellent yield to cinnamyl alcohol ‐3‐14C by aluminum hydride. without attack of the double bond. After purification by column chromatography cinnamyl alcohol ‐3‐14C is obtained with a radioactive overall yield of 65% based on cinnamic acid ‐3‐14C, specific activity = 9 mCi/mM.
An improved synthesis of 5‐fluorouracil‐6‐14C
Authors: Perry C. W. , Burger W. , Bader G. J. , Liebman A. A.
Published: October 2006

Uracil‐6‐14C (7). prepared in high radiochemical yield by conventional methods. has been converted to 5‐fluororacil ‐6‐14C (9) in over 90% yield using trifluoromethylhypofluorite. The use of this recently introduced reagent eliminates the necessity of preparing 9 from fluorinated precursors.
An optimized kinetics model for OH chemiluminescence at high temperatures and atmospheric pressures
Authors: Hall Joel M. , Petersen Eric L.
Published: October 2006

Chemiluminescence from the OH(A → X) transition near 307 nm is a commonly used diagnostic in combustion applications such as flame chemistry, shock‐tube experiments, and reacting‐flow visualization. Although absolute measurements of OH(X) concentrations are well defined, there is no elementary relation between emission from the electronically excited state (OH*) and its absolute concentration. Thus, to enable quantitative emission measurements, a kinetics model has been assembled and optimized to predict OH* formation and quenching at combustion conditions. Shock‐tube experiments were conducted in mixtures of H2/O2/Ar, CH4/O2/Ar, and CH4/H2/O2/Ar with high levels of argon dilution (>98%). Elementary reactions to model OH*, along with initial estimates of their rate coefficients, were taken from the literature. The important formation steps follow:

equation image

equation image

Sensitivity analyses were performed to identify experimental conditions under which the shape of the measured OH* profiles and the magnitude of the OH* emission would be sensitive to the formation reactions. A fitting routine was developed to express the formation rate parameters as a function of a single rate, k1 at the reference temperature (1490 K). With all rates so expressed, H2/CH4 mixtures were designed to uniquely determine the value of k1 at the reference temperature, from which the remaining rate parameters were calculated. Quenching rates were fixed at their literature values. The new model predicts the experimental data over the range of conditions studied and can be used to calibrate the emission diagnostic for other applications, such as measurements in real combustion environments, containing higher order hydrocarbon fuels and lower levels of dilution in air. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 714–724, 2006
Intramolecular carboxylic group‐assisted cleavage of N‐(2‐hydroxyphenyl)phthalamic acid (7) and N‐(2‐methoxyphenyl)phthalamic acid (8): Absence of intramolecular general acid catalysis due to 2‐OH in 7
Authors: Sim Yoke‐Leng , Ariffin Azhar , Khan M. Niyaz
Published: October 2006

The values of pseudo first‐order rate constants (kobs) for the cleavage of N‐(2‐hydroxyphenyl)phthalamic acid (7), obtained at 4.9 × 10−2 M HCl, 35°C, and within CH3CN content range 2–80% (v/v) in mixed aqueous solvent are smaller than kobs for the cleavage of N‐(2‐methoxyphenyl)phthalamic acid (8), obtained under almost similar experimental conditions, by nearly 1.5‐ to 2‐fold. These observations show the absence of expected intramolecular general acid catalysis due to 2‐OH group in 7. The values of kobs for the cleavage of 7 and 8 decrease by more than 20‐fold with the increase in the content of CH3CN from 2 to 80–82% (v/v) in mixed aqueous solvent. The kinetic data reveal that in acidic aqueous cleavage of 7, N‐cyclization (leading to the formation of imide) and O‐cyclization (leading to the formation of phthalic anhydride) vary from ∼10 to 15% and ∼90 to 85%, respectively, with the increase in CH3CN content from 2 to 80% (v/v). Similar increase in CH3CN content causes increase in N‐cyclization from ∼0 to 5% and decrease in O‐cyclization from ∼100 to 95% in the acidic aqueous cleavage of 8. Some speculative, yet conceivable, reasons for nearly 10 and 0% N‐cyclization in the cleavage of respective 7 and 8 at low content of CH3CN have been described. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 746–758, 2006
Decane oxidation in a shock tube
Authors: Olchanski Erna , Burcat Alexander
Published: October 2006

The ignition delay of n‐decane and oxygen diluted in argon was investigated for a series of mixtures ranging from 0.49 to 1.5% decane and 4.16 to 23.25% O2 diluted in argon. The temperature range was 1239–1616 K and the pressure range was 1.82–10.0 atm. All experiments were performed in a heated shock‐tube. An overall ignition delay equation was deduced for 144 experiments: τ = 10−12 exp(+34240/RT)[C10H22]0.60[O2]−1.305[Ar]0.08 s. Product distribution from preignition periods were measured. Detailed simulation schemes available in the literature were checked and a corrected model is proposed that fits well our experiments. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 703–713, 2006
Promotion of the fenton reaction by Cu2+ ions: Evidence for intermediates
Authors: Kremer Mordechai L.
Published: October 2006

The promotion of the Fenton reaction by Cu2+ ions has been investigated using a wide range of [Cu2+]. Both the disappearance of Fe2+ and the evolution of O2 were followed as a function of time by quenching the reaction mixture with o‐phenanthroline or with excess Fe2 + ions, respectively. Two series of experiments were performed. In one series [H2O2] was 5 × 10−4 mol dm−3, and in the other [H2O2] was reduced to 5 × 10−5 mol dm −3. By stopping the reaction with excess Fe2+ ions, significant differences in the measured absorbance in the two series were observed. In the higher [H2O2] range, the absorbance decreased monotonically in time, due to O2 formation during the reaction. In the lower range, an initial transient rise of the absorbance was observed, indicating the formation of spectroscopically distinct intermediates in the system. A mechanism involving the intermediates FeOCu4+ and FeOCu5+ has been set up. Rate constants of the mechanism have been determined. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 725–736, 2006
Kinetics of base hydrolysis of α‐amino acid esters catalyzed by the copper(II) complex of N,N,N′,N′‐tetramethylethylenediamine (Me4en)
Authors: Mohamed Mahmoud M. A. , Shoukry Azza A. , Shoukry Mohamed M.
Published: October 2006

The kinetics of base hydrolysis of glycine‐, histidine‐, and methionine methyl esters in the presence of [Cu‐Me4en]2+ complex is studied in aqueous solutions and in dioxane–water solutions of different compositions at T = 25°C and I = 0.1 mol dm−1. The kinetics of base hydrolysis of glycine and methionine methyl esters is studied at different temperatures. The kinetic data fits assuming that the hydrolysis proceeds in one step. The activation parameters for the base hydrolysis of the complexes are evaluated. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 737–745, 2006
FiberID—A technique to identify fibrous protein subclasses
Authors: Waltman Peter , Blumer Anselm , Kaplan David
Published: October 2006

Fibrous proteins such as collagen, silk, and elastin play critical biological roles, yet they have been the subject of few projects that use computational techniques to predict either their class or their structure. In this article, we present FiberID, a simple yet effective method for identifying and distinguishing three fibrous protein subclasses from their primary sequences. Using a combination of amino acid composition and fast Fourier measurements, FiberID can classify fibrous proteins belonging to these subclasses with high accuracy by using two standard machine learning techniques (decision trees and Naïve Bayesian classifiers). After presenting our results, we present several fibrous sequences that are regularly misclassified by FiberID as sequences of potential interest for further study. Finally, we analyze the decision trees developed by FiberID for potential insights regarding the structure of these proteins. Proteins 2007. © 2006 Wiley‐Liss, Inc.
Multiple Regression and Principal Component Analysis of Antibacterial Activities of Sulfones and Sulfonamides in Whole Cell and Cell‐Free Systems of Various DDS Sensitive and Resistant Bacterial Strains
Authors: Coats E. A. , Cordes H.‐P. , Kulkarni V. M. , Richter M. , Schaper K.‐J. , Wiese M. , Seydel J. K.
Published: October 2006

Antibacterial effects of sulfones and sulfonamides have been determined in cell‐free folate synthesizing enzyme extracts and in whole cell cultures of various mycobacterial strains and E. coli sensitive and resistant to sulfones. Structural dependency of the observed activities has been quantitatively explained by multiple regression and principal component analysis. Both types of analyses lead to the same conclusion concerning the importance of electronic influences of substituents. In addition the influence of lipophilicity for the transport into the cells is demonstrated by the results of the PCA‐analysis. The importance of the results for the mode of action and the mechanism of resistance is discussed.
A Shape Index from Molecular Graphs
Authors: Kier Lemont B.
Published: October 2006

A numerical index of molecular shape has been derived from the graph of the non‐hydrogen molecular skeleton. The index is based on the count of 2‐bond fragments in a graph relative to the maximum number possible in the isomeric star graph and the minimum number in the isomeric linear graph. In this initial study all non‐hydrogen atoms and all bonds are considered equal. The 2κ index describes the molecular shape in relationship to the star and linear graph and is normalized to the number of atoms. Applications are presented for shape similarity estimation, cavity filling ability and QSAR analyses.
QSAR for Cholinesterase Inhibition by Organophosphorus Esters and CNDO/2 Calculations for Organophosphorus Ester Hydrolysis
Authors: Johnson Howard , Kenley Richard A. , Rynard Carolyn , Golub Morton A.
Published: October 2006

Quantitative structure‐activity relationships were derived for acetyl‐ and butyrylcholinesterase inhibition by various organophosphorus esters. Bimolecular inhibition rate constants correlate well with hydrophobic substituent constants, and with the presence or absence of cationic groups on the inhibitor, but not with steric substituent constants. CNDO/2 calculations were performed on a separate set of organophosphorus esters, RR′P(O)X, where R and R′ are alkyl and/or alkoxy groups and X is fluorine, chlorine or a phenoxy group. For each subset with the same X, the CNDO‐derived net atomic charge at the central phosphorus atom in the ester correlates well with the alkaline hydrolysis rate constant. For the whole set of esters with different X, two equations were derived that relate either charge and leaving group steric bulk, or orbital energy and bond order to the hydrolysis rate constant.
Co‐op students' access to shared knowledge in science‐rich workplaces
Authors: Munby Hugh , Taylor Jennifer , Chin Peter , Hutchinson Nancy L.
Published: October 2006

Wenger's (1998) concepts “community of practice,” “brokering,” and “transfer” explain the challenges co‐operative (co‐op) education students face in relating the knowledge learned in school with what they learn while participating as members of a workplace. The research for this paper is set within the contexts of the knowledge economy and increased collaboration in the workplace. The paper draws on several qualitative studies of work‐based education to examine the similarities and differences between learning in the workplace and learning in school, with a focus on science education and science‐rich workplaces. Barriers to connecting school knowledge and workplace knowledge include the nature of science (its purpose, accountability, and substance), the structure of knowledge in each setting, the form content knowledge takes, the sequence that the curriculum is presented in, and the gatekeeping that occurs when knowledge is accessed. The paper addresses implications for interventions in school and the workplace, with attention to the transition from school to work, and concludes by pointing to profound obstacles to connecting school knowledge with workplace knowledge. © 2006 Wiley Periodicals, Inc. Sci Ed 91:115–132, 2007
From an awareness of scientific data to concerns of mankind: Strategies for affective instruction in science
Authors: Baker Milton R. , Doran Rodney L.
Published: October 2006

And God said, Let us make man in our image after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.
Five years of achievement in ISCS
Authors: McDuffie Thomas E. , Derose James V.
Published: October 2006

Achievement associated with a school district committed to the implementation of the Intermediate Science Curriculum Study (ISCS) materials and instructional strategy is the focus of this report. While ISCS is a three level, activity oriented, junior high program, the research was limited to the first year or Level I. Data were gathered from Level I students (mostly seventh graders) during a five year period. Analyses were per‐ formed to help answer questions such as: Are IQ and reading scores the highest correlates of achievement? Do IQ and reading correlates hold for both quantitative and qualitative indices of achievement? Do ISCS learning relationships hold over time? Are students able to evaluate how well they understand the concepts covered?
Science, stories, and sense‐making: A comparison of qualitative data from a wetlands unit
Authors: Hulland Carol , Munby Hugh
Published: October 2006

Posner's theory of conceptual change forms the background for this study which focuses upon conceptual ecology, specifically upon the heuristics children appear to employ in sense‐making. The study reports data from a 2‐week wetland unit conducted during a summer camp program. The data consist of tape recordings and drawings made by the children. The analysis focuses upon two children who demonstrate remarkably different sense‐making heuristics: a recognizably scientific one and one that involves the generation of metaphors and personalized stories. The study argues the importance of attending to the heuristics of sense‐making in studies of conceptual ecology and conceptual change. © 1994 John Wiley & Sons, Inc.
Understanding a basic biological process: Expert and novice models of meiosis
Authors: Kindfield Ann C. H.
Published: October 2006

Central to secondary and college‐level biology instruction is the development of student understanding of a number of subcellular processes. Yet some of the most crucial are consistently cited as the most difficult components of biology to learn. Among these is meiosis. In this article I report on the meiosis models utilized by five individuals at each of three levels of expertise in genetics as each reasoned about this process in an individual interview setting. Detailed characterization of individual meiosis models and comparison among models revealed a set of biologically correct features common to all individuals' models as well as a variety of model flaws (i.e., meiosis misunderstandings) which are categorized according to type and level of expertise. These results are suggestive of both sources of various misunderstandings and factors that might contribute to the construction of a sound understanding of meiosis. Each of these is addressed in relation to their respective implications for instruction.
Gender, ethnicity, and students' perceptions about science and science‐related careers in Fiji
Authors: Rennie Leonie J. , Dunne Mairead
Published: October 2006

This study examines the relationships between gender, ethnicity, and Fijian students' attitudes and perceptions about science, attributions of success and failure in science as school, science as a career, and the career‐related advice they received. Data were collected with a questionnaire administered to a stratified, random, one‐sixth sample of Form 5 (16‐year‐old) students in Fiji. Gender and ethnicity were found to have no consistent relationship with students' perceptions, attitudes, and attributions about science. However, students, particularly males, demonstrated strong sex‐stereotyping of science‐related careers, and different kinds of career advice were given to students on the basis of their gender and ethnicity. These, rather than students' attitudes and performance in science, are more likely to explain the patterns linking gender and ethnicity with the science‐related work force and higher education in Fiji.
Bringing pupils' learning closer to a scientific construction of knowledge: A permanent feature in innovations in science teaching
Authors: Gil‐Perez Daniel , Carrascosa‐Alis Jaime
Published: October 2006

In this article we intend to show that the idea of linking science learning to the way of doing science constitutes a permanent feature, although not always explicit, in innovations in science teaching. A thread which, in our opinion, has shown itself to be fruitful, even through its wrong avenues, and that is being reinforced nowadays by the emerging constructivist paradigm and by the implications of the contemporary philosophy of science in science education.
Software support for students engaging in scientific activity and scientific controversy
Authors: Cavalli‐Sforza Violetta , Weiner Arlene W. , Lesgold Alan M.
Published: October 2006

Computer environments could support students in engaging in cognitive activities that are essential to scientific practice and to the understanding of the nature of scientific knowledge, but that are difficult to manage in science classrooms. The authors describe a design for a computer‐based environment to assist students in conducting dialectical activities of constructing, comparing, and evaluating arguments for competing scientific theories. Their choice of activities and their design respond to educators' and theorists' criticisms of current science curricula. They give detailed specifications of portions of the environment. © 1994 John Wiley & Sons, Inc.
Teaching evolution using historical arguments in a conceptual change strategy
Authors: Jensen Murray S. , Finley Fred N.
Published: October 2006

A historically rich teaching intervention was developed for biological evolution with the intent of promoting a conceptual change from students' initial understanding to a more Darwinian understanding. The intervention was delivered in a small group setting to underprepared, entry–level biology students. Evaluation of the treatment, using pre–post testing, was used to document the general effectiveness of the intervention and specific changes in students' conceptions of evolution. Results indicate the use of historical materials in conjunction with a conceptual change strategy to be promising. Specific strengths and weaknesses in specific areas of biological evolution are documented. © 1995 John Wiley & Sons. Inc.
“Developmental research” as a way to an empirically based “didactical structure” of science
Authors: Lijnse P. L.
Published: October 2006

In the past decades, much work has been done in science education on large–scale curriculum development, ranging from a “structure–of–the–discipline” approach to STS. At the same time, research on students' ideas has drawn attention to the underestimated problems of learning and teaching, which may largely explain the limited success of the curriculum efforts as far as cognitive learning is concerned. Proposed solutions are mainly inspired by a constructivist cognitive science perspective and are formulated as general teaching strategies that aim at a more or less forced process of “conceptual change.” However, in our view, “developmental research” is needed in which small–scale curriculum development is cyclically coupled to indepth classroom research of teaching–learning processes. Such research should resuit in worked out examples of successful ways of teaching, according to new conceptual curriculum structures. Designing such “didactical” structures constitutes a longer term research program, which asks for international exchange and cooperation. © 1995 John Wiley & Sons, Inc.
The development and validation of an assessment of safety awareness of science teachers using interactive videodisc technology
Authors: Lomask Michal S. , Jacobson Larry , Hafner Laurin P.
Published: October 2006

A new assessment of science teachers' knowledge of school lab safety management was developed and tested. The assessment, called the Safety Simulator, is based on Interactive Videodisc (IVD) technology and was developed as part of the Beginning Educator Support and Training program for beginning teachers in Connecticut. The Safety Simulator contains two phases: 1) A “walk” through the lab room, designed to assess teacher knowledge of current regulations about safety equipment and storage of chemicals; 2) A General science lab activity, performed by four middle school students, designed to assess teacher knowledge of school safety management and his/her ability to monitor students' work. Reliability of scores for the four different categories of school lab safety (Physical facilities, Chemicals. Lab techniques and Students' behavior), examined by calculating the mean correlation coefficients among three different scorers, was found to be moderate to high. Evidence for content and construct validity were studied by examining job relatedness, safety expert judgment, and by comparing the performance of known groups. © 1995 John Wiley & Sons, Inc.
Origins of life science teachers' beliefs underlying curriculum reform in Texas
Authors: Crawley Frank E. , Salyer Barbara A.
Published: October 2006

This study explores the beliefs about reform of life science teachers in central Texas who were retained to teach Coordinated Thematic Science I. In particular, we were interested in identifying the beliefs that serve as the foundation for the grade 7 life science teachers' intentions to introduce physical science activities in the life science classes they teach. To accomplish this purpose, we selected four teachers, using purposeful sampling procedures. We also adapted an empirical model for investigating rational decisionmaking, the Theory of Planned Behavior, for use in an interview format. Two additional data sources were used to triangulate our findings set out in seven assertions developed from the 52 pages of transcribed interviews. Our results call attention to the need for all three levels of education—state, district, and school—to cooperate in implementing science curriculum reform in Texas. © 1995 John Wiley & Sons, Inc.
Students' conceptual ecologies and the process of conceptual change in evolution
Authors: Demastes Sherry S. , Good Ronald G. , Peebles Patsye
Published: October 2006

Using conceptual change as a theoretical lens, the purpose of this study is to describe the structure of a learner's conceptual ecology within a specific content area (biological evolution) and to illustrate how this ecology influences the process of conceptual change. Data were gathered using participant observations in a high school Biology II classroom as well as a series of 17 open‐ended and structured interviews with each of four research participants. The interviews were designed to illustrate the participants' approaches to biology as well as to describe their changing conceptual frameworks for evolutionary theory. Interview techniques used include: concept mapping, drawing interviews, discussion of pre‐ and posttests, and sorting tasks. A learner's conceptual ecology for evolution was found to include prior conceptions related to evolutionary theory (both scientific and alternative), scientific and religious orientations, view of the biological world, and acceptance of evolutionary theory. However, the data demonstrate that the actions of these aspects of the conceptual ecology can vary among individuals and no single controlling mechanism was isolated. Most importantly, the data demonstrate that conceptual change has significant affective cornponents as evidence is evaluated by learners and this evaluation is often based on extralogical criteria. © 1995 John Wiley & Sons, Inc.
Evaluating from a management perspective
Authors: Harpel Richard I.
Published: October 2006

If their programs are to compete for limited resources, student services professionals must learn to adopt a management point of view when they make assessments.
Method, design, and instrumentation in evaluation
Authors: Oetting Eugene R. , Cole Charles W.
Published: October 2006

Here is a cookbook for a good evaluation plan that avoids the three major sources of failure: inadequate research design, weak impact, and poor selection or construction of outcome measures.
The report: Explaining findings and recommendations
Authors: Brown Robert D.
Published: October 2006

A report on coeducational dormitory life illustrates how an evaluation study can be summarized.
Conclusions and further resources
Authors: Hanson Gary R.
Published: October 2006

This summary identifies five critical characteristics of good evaluation and notes additional sources of information on evaluation for the interested reader.
Why students stay, why they leave
Authors: Cope Robert G.
Published: October 2006

Improving the social and academic integration of student and institution is the surest way to improve retention; yet the doors must revolve freely, since leaving college can also be a positive step.
Admissions management with the focus on retention
Authors: Ott Linda S.
Published: October 2006

As imaginative retention strategies are created on our campuses, admissions offices must demonstrate how ongoing operations, programs, and processes relate to—and potentially enhance—student persistence.
Retaining adults: New educational designs for a new clientele
Authors: Miller Myrna R.
Published: October 2006

Programs offered for adult learners must be designed to overcome the internal and external constraints that older students experience.
Some plain talk on retention by a college dean
Authors: Jose James R.
Published: October 2006

You and I may be retention problems, so let's not hesitate to raise questions that might embarrass us.
First steps in starting a campus retention program
Authors: Noel Lee
Published: October 2006

A concerted effort to increase student retention will force the institution to examine itself closely and what is observed will not always be pleasant or easy to accept. Students will persist if the institution is delivering lively, substantive learning and growth experiences.
Consultation evaluation: Turning a circus into a performance
Authors: Paul Stephen C.
Published: October 2006

Consultants are proactive change agents for others who should consider becoming proactive evaluators for themselves.
Technology and student services personnel: Current use and future applications
Authors: Johnson Cynthia S. , Riesenberg Bruce
Published: October 2006

Whereas the late 1960s and the 1970s have been a period of new developments, experimentation, and increasing technological innovation in student services, the 1980s should prove to be an exciting period of technological refinement and expanded application.
New Ideas: Will they work?
Authors: Ford Michael
Published: October 2006

If new student services programs are to work, student personnel professionals must learn to systematically look before they leap.
Once you've got it, how do you keep it?
Authors: Justice Sharon H. , Ragle John D.
Published: October 2006

Creativity, ingenuity, and thoughtful appraisal are necessary to strengthen and maintain established student service programs.
The role of faculty in working with handicapped students
Authors: Walker Martha Lentz
Published: October 2006

Program accessibility hinges upon faculty involvement, yet faculty members are often ill‐prepared to teach students with disabilities.
Implications for student development specialists and counselor educators
Authors: Marx Pat , Schmidt Marlin R.
Published: October 2006

Increased attention to programs for the handicapped may force colleges and universities to take a different look at their student personnel training programs.
Concluding remarks
Authors: Schmidt Marlin R. , Sprandel Hazel Z.
Published: October 2006

The main themes that have emerged in preceding articles and the myths that contribute to attitudinal barriers are considered, and some predictions and recommendations for the future are proposed.
Sources of additional assistance: Organizations
Authors: Sprandel Hazel Z. , Schmidt Marlin R.
Published: October 2006

Because most student services administrators have not had training in providing services for the handicapped, they will be interested in the many organizations and agencies that offer information and resources for services for handicapped persons.
The role of the adult student resource center
Authors: Schuster Diane Tickton , Berner Andrew J.
Published: October 2006

The one‐stop adult student resource center is an efficient and visible way colleges can provide programs based on the developmental needs of adult students.
The Handyperson's guide to student aid research
Authors: Van Dusen William D.
Published: October 2006

Student aid research is not—or should not be—hard for the practitioner to do. Here are a few suggestions for why and how more aid administrators should add the term researcher to the list of their functions.
Student consumer information: The right to know—the responsibility to learn
Authors: Howell Samuel
Published: October 2006

The choice of a college or university and a course of study is a significant decision for the prospective student. In a move to ensure the availability of adequate information on which to base that decision the federal government has mandated that certain information be provided to all prospective students by institutions that receive federal Title IV financial assistance funds.
The application of open system theory to student financial aid administration
Authors: Binder Shirley F.
Published: October 2006

The unprecedented growth and complexity of financial assistance programs have increased the necessity for administrators of college and university student financial aid offices to possess management skills so that those offices can be integrated into institutional plans and priorities.
A philosophy of community development for residence halls
Authors: Hennessy Thomas J.
Published: October 2006

The quality of the interactive process is greatly enhanced by a strong sense of community.
Environmental structuring: Residence halls as living learning centers
Authors: Rowe Linda Pedretty
Published: October 2006

Although most student affairs administrators agree that living learning programs integrate social and intellectual development, it is not always clear how to create such an environment. This chapter provides a practical model for structuring residence halls as living learning centers.
Annotated references
Authors: Diehl Janice L.
Published: October 2006

These concise descriptions of recommended literature acquaint residence education professionals with work in the field.
Career development needs of special populations
Authors: Smith Elsie J.
Published: October 2006

The issues that affect the academic success, retention and career decisions of special populations require special methods for providing career development services.
Developing faculty as facilitators and mentors
Authors: Gardner John N.
Published: October 2006

The nation's over 11 million college students need far more career counseling than student personnel professionals have the staff to provide. How will this demand be met? The nation's 830,000 faculty, if trained as facilitators and mentors, can help close this gap.
The college environment
Authors: Mable Phyllis , DeCoster David A.
Published: October 2006

Constantly questioning the college environment, students alternately criticize both involvement and apathy. Although disappointed by the ineffectiveness of student governance, they recognize the merits of participating in institutional decision making.
Facilitating human development through administrative leadership
Authors: Wilson Milton E.
Published: October 2006

Satisfactions and dissatisfactions of students in postsecondary institutions should challenge administrators to be visionary and assertive in managing the educational enterprise for human development.