bluuebunny/crossref_metadata_2025 huggingface dataset:
Probing the Transition between the Localised (Class II) and Localised‐to‐Delocalised (Class II–III) Regimes by Using Intervalence Charge‐Transfer Solvatochromism in a Series of Mixed‐Valence Dinuclear Ruthenium Complexes
Authors: D'Alessandro Deanna M. , Topley Amy C. , Davies Murray S. , Keene F. Richard
Published: April 2006

Intervalence charge‐transfer (IVCT) solvatochromism studies on the diastereoisomeric forms of [{Ru(bpy)2}2(μ‐BL)]5+ (bpy=2,2′‐bipyridine; BL=a series of di‐bidentate polypyridyl bridging ligands) reveal that the solvent dependencies of the IVCT transitions decrease as the “tail” of the bridging ligand is extended, and the extent of delocalisation increases. Utilising a classical theoretical approach for the analysis of the intervalence charge‐transfer (IVCT) solvatochromism data, the subtle and systematic variation in the electronic properties of the bridging ligands can be correlated with the shift between the localised (class II) and localised‐to‐delocalised (class II–III) regimes. The investigation of the diastereoisomeric forms of two series of complexes incorporating analogous structurally rigid (fused) and nonrigid (unfused) bridging ligands demonstrates that the differences in the IVCT characteristics of the diastereoisomers of a given complex are accentuated in the latter case, due to a stereochemically induced redox asymmetry contribution. The marked dependence of the IVCT transitions on the stereochemical identity of the complexes provides a quantitative measure of the fundamental contributions of the reorganisational energy and redox asymmetry to the intramolecular electron‐transfer barrier at the molecular level.
Cover Picture: From Allylic Alcohols to Aldols through a New Nickel‐Mediated Tandem Reaction: Synthetic and Mechanistic Studies (Chem. Eur. J. 12/2006)
Authors: Cuperly David , Petrignet Julien , Crévisy Christophe , Grée René
Published: April 2006

Atom economical reactions that involve mild and neutral reaction conditions are currently an important challenge in synthesis. In their Full Paper on page 3261 ff., R. Grée et al. describe a new tandem isomerization–aldolization process. The cover highlights 1) the novelty of using allylic alcohols as partners for the preparation of aldols, 2) the key role of free enols as intermediates, and 3) (in the middle) the postulated transition state of this reaction. The picture behind the scheme shows the high tide at St. Malo, a famous port and city near Rennes where this research has been performed.
Thermochemical Study on the Chiral Sodium Zincophosphate Nanocrystalline
Authors: Wu Jian , Yuan Ai‐Qun , Huang Zai‐Yin , Song Bao‐Lin , Liao Sen
Published: April 2006

Chiral sodium zincophosphate nanocrystalline has been prepared and characterized. The standard molar enthalpy of the following reaction 12Na3PO4·12H2O(s)+12ZnSO4·7H2O(s)=Na12(Zn12P12O48)·12H2O(s)+12Na2SO4(s)+216H2O(l) was determined by solution reaction calorimetric at 298.15 K, and calculated to be 33.666±0.195 kJ/mol. From the results and other auxiliary quantities, the standard enthalpy of formation for sodium zincophosphate nanocrystalline was derived to be Δ fH⊖m [Na12(Zn12P12O48)·12H2O(s), 298.15 K]=−24268.494±0.815 kJ/mol.
Morphology Investigation of Electrolessly Deposited Ag Film on Ag‐Activated p‐Type Silicon(111) Wafer
Authors: Tong Hao , Wang Chun‐Ming
Published: April 2006

A method of electroless silver deposition on silver activated p‐type silicon(111) wafer was proposed. The silver seed layer was deposited firstly on the wafer in the solution of 0.005 mol/L AgNO3+0.06 mol/L HF. Then the silver film was electrolessly deposited on the seed layer in the electroless bath of AgNO3+NH3+acetic acid+NH2NH2 (pH 10.2). The morphology of the seed layer and the silver films prepared under the condition of the different bath composition was compared by atomic force microscopy. The reflectance of the silver films with different thickness was characterized by Fourier transform infrared spectrometry. The experimental results indicate that the seed layer possesses excellent catalytic activity toward electroless silver deposition and rotating of the silicon wafer during the electroless silver deposition could lead to formation of the smoother silver film.
Synthesis, Photochromic Kinetics, Fluorescence and Structure of a New 1,2‐Diarylcyclopentene
Authors: Pu Shou‐Zhi , Xiao Qiang , Xu Jing‐Kun , Shen Liang , Li Gui‐Zhen , Chen Bing
Published: April 2006

The photochromic diarylethene, 1,2‐bis[2‐methyl‐5‐(3‐trifluoromethylphenyl)‐3‐thienyl]perfluorocyclopentene (BMTTP), was synthesized and its photochromic kinetics, fluorescence and X‐ray structure were investigated. This compound underwent a photochromic reaction both in solution and the single crystalline phase. Its cyclization/cycloreversion process was determined to be zeroth/first order reaction, respectively, and this is the first report on the cyclization/cycloreversion reaction order. In addition, its fluorescence property was also discussed.
Synthesis, Crystal Structures, Thermal Analysis and Magnetic Property of Mono‐ and Bi‐nuclear 1,1‐Cyclobutanedicarboxy‐ late Copper Complexes
Authors: Li Ming‐Xing , Dai Hui , Shao Min , Shi Lei , Lin Kun‐Hua , Cheng Zhi‐Xuan , Weng Lin‐Hong
Published: April 2006

Two new copper complexes, [Cu(cbdc)(phen)(H2O)]·2H2O (1) and [Cu2(cbdc)(phen)2(H2O)2](ClO4)2·H2O (2) (cbdc=1,1‐cyclobutanedicarboxylate and phen=1,10‐phenanthroline), were synthesized by reaction of cbdc with Cu(ClO4)2and phen in ethanol aqueous solution. Complex1crystallizes in monoclinic system with space groupP2(1)/canda=0.9428(4) nm,b=1.2183(5) nm,c=1.6265(7) nm,β=102.418(5)°,V=1.8246(13) nm3,Z=4,R=0.0445,wR2=0.0947. The structure of1is discretely mononuclear, which is packed by π···π interaction forming a 3D supramolecular structure where Cu(II) ion is five‐coordinated and has square‐pyramidal coordination geometry. Its thermal decomposition procedure detail was studied by thermal analysis TG‐DSC. Complex2belongs to monoclinic system with space groupP2(1)/canda=0.8897(3) nm,b=1.9130(8) nm,c=1.9936(8) nm,β=99.04(2)°,V=3.351(2) nm3,Z=4,R=0.0540,wR2=0.1102. The structure of2is a discrete binucleus, where Cu(1) is four‐coordinated by phen and cbdc in a square‐planar geometry while Cu(2) is five‐coordinated by phen, one O of cbdc and two H2O, which can be best described as distorted trigonal‐bipyramidal geometry. Cu(1) and Cu(2) are linked by carboxylic group of cbdc in a bidentate bridging fashion. Variable‐temperature magnetic susceptibilities of2in 2–300 K showed that its magnetic behavior obeyed Curie law.
Synthesis of Novel Nucleoside Analogues Based on 1,3‐Dihydrobenzo[c]furan Core
Authors: Liu Zhao‐Peng , Meng Zhao‐Li , Wang De‐Feng
Published: April 2006

A novel efficient synthetic route to 1,3‐dihydrobenzo[c]furan glycone was developed and the corresponding 5‐fluoro, 5‐iodo uracil and guanosine derivatives, the aromatic analogues of the well known antiviral 2′,3′‐dideoxy‐2′,3′‐dihydronucleosides (d4N), were synthesized.
Two Multi‐armed Neutral Receptors for α,ω‐Dicarboxylate Anions
Authors: Wu Jin‐Long , He Yong‐Bing , Wei Lan‐Hua , Liu Shun‐Ying , Xu Kuo‐Xi , Meng Ling‐Zhi
Published: April 2006

Two new multi‐armed neutral receptors 1 and 2 containing thiourea and amide groups were synthesized by simple steps in good yields. Receptors 1 and 2 have a better selectivity and higher association constants for malonate anion than other anions examined by the present work. In particular, distinct color changes were observed upon addition of dicarboxylate anions to the solution of 1 in DMSO. The UV‐Vis and fluorescence spectra data indicate that a 1:2 stoichiometry complex was formed between compound 1 or 2 and dicarboxylate anions of shorter carbon chain, and a 1:1 stoichiometry complex was formed between compound 1 or 2 and dicarboxylate anions of longer carbon chain through hydrogen bonding interactions.
Synthesis of a Novel Discrete Metallacycle Complex Self‐assembled into a 3D Hydrogen‐binding Supramolecular Structure
Authors: Wu Ben‐Lai , Zhang Hong‐Yun , Wu Qing‐An , Hou Hong‐Wei , Zhu Yu , Ye Bao‐Xian
Published: April 2006

A novel discrete dinuclear metallacyclic copper(II) complex, [Cu2L2(H2O)2]·3H2O (1) has been firstly prepared where L is derived from the 1:2 condensation of 2,2′‐bipyridyl‐3,3′‐diformylhydrazide and acetone during the formation of the complex. Single‐crystal X‐ray diffraction analysis determines that the complex consists of dinuclear metallacyclic units [Cu2L2(H2O)2] where two metal centers are linked together through two bis(chelating) bridge ligands L to form a bizarre cavity with size 0.9417 nm×0.4999 nm×0.6930 nm. Interestingly, the metal coordination also creates hydrogen bond sites that further aggregate these metallacycles into a 3D supramolecular structure with 2D perpendicular hydrophilic tunnels in crystal.
para‐Dialkylaminophenyl Dyes for Efficient Nanocrystalline TiO2 Sensitization in Far‐red Region
Authors: Li Chao , Zhou Jia‐Hong , Chen Jing‐Rong , Chen You‐Sheng , Zhang Xue‐Hua , Ding Hui‐Ying , Wang Wei‐Bo , Wang Xue‐Song , Zhang Bao‐Wen
Published: April 2006

Four para‐dialkylaminophenyl (PDAAP1–PDAAP4) bearing carboxyl groups were studied for application to the dye‐sensitized solar cells (DSC). It was found the short spacer CH2 between carboxyl and dialkylaminophenyl chromophore in PDAAP3 and PDAAP4 led to highly efficient monochromatic incident photon‐to‐current conversion efficiencies (IPCE), however the long alkyl group C4H9 attached on aniline moieties in PDAAP2 and PDAAP4 favored improvement of open‐circuit photovoltage. Thus, the solar cell sensitized by PDAAP4, having both short carboxyl groups CH2COOH and long alkyl groups C4H9, exhibited the IPCE maximum of 73% at 670 nm and overall energy conversion efficiency η of 3.06%, representing the highest IPCE and η values so far in dialkylaminophenyl‐based organic dye‐sensitized semiconductor solar cells. Taking advantage of the highly efficient sensitizing ability of PDAAP4 in far‐red region, the data of IPCE above 630 nm of the solar cells were improved greatly by cosensitization with both N3 and PDAAP4. The influences of the TiO2 film thickness and the concentration of 4‐tert‐butylpyridine (TBP) in electrolyte were also investigated.
Hydrogen‐bonded Lamellar Network of Pyromellitic Acid Pillared by 8‐Hydroxyquinoline
Authors: Wang Lei , Zhang Hong , Zhang Jing‐Ping , Gao Fei‐Xue , Hua Rui‐Mao , Zhou Guang‐Yuan
Published: April 2006

8‐Hydroxyquinoline (8‐q) salt of pyromellitic acid (benzene‐1,2,4,5‐tetracarboxylic acid, H4bta) forms robust lamellar structure where [H2bta]2− anions build up sheets through strong hydrogen bonds in two dimensions and [H‐8‐q]+ cations act as pillars to afford an extended three dimensional network.
Kinetic analysis of hyaluronidase activity using a bioactive MRI contrast agent
Authors: Shiftan Liora , Neeman Michal
Published: April 2006

One of the attractions of molecular imaging using ‘smart’ bioactive contrast agents is the ability to provide non‐invasive data on the spatial and temporal changes in the distribution and expression patterns of specific enzymes. The tools developed for that aim could potentially also be developed for functional imaging of enzyme activity itself, through quantitative analysis of the rapid dynamics of enzymatic conversion of these contrast agents. High molecular weight hyaluronan, the natural substrate of hyaluronidase, is a major antiangiogenic constituent of the extracellular matrix. Degradation by hyaluronidase yields low molecular weight fragments, which are proangiogenic. A novel contrast material, HA‐GdDTPA‐beads, was designed to provide a substrate analog of hyaluronidase in which relaxivity changes are induced by enzymatic degradation. We show here a first‐order kinetic analysis of the time‐dependent increase in R2 as a result of hyaluronidase activity. The changes in R2 and the measured relaxivity of intact HA‐GdDTPA‐beads (r2B) and HA‐GdDTPA fragments (r2D) were utilized for derivation of the temporal drop in concentration of GdDTPA in HA‐GdDTPA‐beads as the consequence of the release of HA‐GdDTPA fragments. The rate of dissociation of HA‐GdDTPA from the beads showed typical bell‐shaped temperature dependence between 7 and 36 °C with peak activity at 25 °C. The tools developed here for quantitative dynamic analysis of hyaluronidase activity by MRI would allow the use of activation of HA‐GdDTPA‐beads for the determination of the role of hyaluronidase in altering the angiogenic microenvironment of tumor micro metastases. Copyright © 2006 John Wiley & Sons, Ltd.
Thermodynamic and Ab Initio Analysis of the Controversial Enthalpy of Formation of Formaldehyde
Authors: da Silva Gabriel , Bozzelli Joseph W. , Sebbar Nadia , Bockhorn Henning
Published: April 2006

There are two values, −26.0 and −27.7 kcal mol−1, that are routinely reported in literature evaluations for the standard enthalpy of formation, Δf H°298, of formaldehyde (CH2O), where error limits are less than the difference in values. In this study, we summarize the reported literature for formaldehyde enthalpy values based on evaluated measurements and on computational studies. Using experimental reaction enthalpies for a series of reactions involving formaldehyde, in conjunction with known enthalpies of formation, its enthalpy is determined to be −26.05±0.42 kcal mol−1, which we believe is the most accurate enthalpy currently available. For the same reaction series, the reaction enthalpies are evaluated using six computational methods: CBS‐Q, CBS‐Q//B3, CBS‐APNO, G2, G3, and G3B3 yield Δf H°298=−25.90±1.17 kcal mol−1, which is in good agreement to our experimentally derived result. Furthermore, the computational chemistry methods G3, G3MP2B3, CCSD/6‐311+G(2df,p)//B3LYP/6‐31G(d), CCSD(T)/6‐311+G(2df,p)//B3LYP/6‐31G(d), and CBS‐APNO in conjunction with isodesmic and homodesmic reactions are used to determine Δf H°298. Results from a series of five work reactions at the higher levels of calculation are −26.30±0.39 kcal mol−1 with G3, −26.45±0.38 kcal mol−1 with G3MP2B3, −26.09±0.37 kcal mol−1 with CBS‐APNO, −26.19±0.48 kcal mol−1 with CCSD, and −26.16±0.58 kcal mol−1 with CCSD(T). Results from heat of atomization calculations using seven accurate ab initio methods yields an enthalpy value of −26.82±0.99 kcal mol−1. The results using isodesmic reactions are found to give enthalpies more accurate than both other computational approaches and are of similar accuracy to atomization enthalpy calculations derived from computationally intensive W1 and CBS‐APNO methods. Overall, our most accurate calculations provide an enthalpy of formation in the range of −26.2 to −26.7 kcal mol−1, which is within computational error of the suggested experimental value. The relative merits of each of the three computational methods are discussed and depend upon the accuracy of experimental enthalpies of formation required in the calculations and the importance of systematic computational errors in the work reaction. Our results also calculate Δf H °298 for the formyl anion (HCO−) as 1.28±0.43 kcal mol−1.
Novel Superalkali Superhalogen Compounds (Li3)+(SH)−(SH=LiF2, BeF3, and BF4) with Aromaticity: New Electrides and Alkalides
Authors: Wang Fang‐Fang , Li Zhi‐Ru , Wu Di , Sun Xiao‐Ying , Chen Wei , Li Ying , Sun Chia‐Chung
Published: April 2006

Optimized structures, with all real frequencies, of superalkali superhalides (Li3)+(SH)−(SH=LiF2, BeF3, and BF4), are obtained, for the first time, at the B3LYP/aug‐cc‐pVDZ and MP2/aug‐cc‐pVDZ computational levels. These superalkali superhalides possess three characteristics that are significantly different from normal alkali halides. 1) They have a variety of structures, which come from five bonding mode types: edge–face, edge–edge, face–face, face–edge, and staggered face–edge. We find that the bonding mode type closely correlates with the Li3SH bond energy. 2) The valence electrons on the Li3ring are pushed out by the (SH)−anion, and become excess electrons, conferring alkalide or electride characteristics on these Li3SH species, depending on the bonding mode type. 3) The highest occupied molecular orbital of each Li3SH species is a doubly occupied delocalized σ bonding orbital on the Li3ring, which indicates its aromaticity. It is noticeable that the maximum negative nucleus‐independent chemical shift value (about −10 ppm) moves out from the center of the Li3ring, owing to repulsion by the SH−anion. We find that these superalkali superhalides are not only complicated “supermolecules”, but are also a new type of alkalide or electride, with aromaticity.
Glutathione‐S‐transferase‐green fluorescent protein fusion protein reveals slow dissociation from high site density beads and measures free GSH
Authors: Tessema Mathewos , Simons Peter C. , Cimino Daniel F. , Sanchez Lilliana , Waller Anna , Posner Richard G. , Wandinger‐Ness Angela , Prossnitz Eric R. , Sklar Larry A.
Published: April 2006

Background:

Glutathione, a ubiquitous tripeptide, is an important cellular constituent, and measurement of reduced and oxidized glutathione is a measure of the redox state of cells. Glutathione‐S‐transferase (GST) fusion proteins bind naturally to beads derivatized with glutathione, and elution of such bead‐bound fusion proteins with buffer containing millimolar glutathione is a commonly used method of protein purification. Many protein–protein interactions have been established by using GST fusion proteins and measuring binding of fusion protein binding partners by GST pulldown assays, usually monitored by Western blot methodology.

Methods:

Dextran beads suitable for flow cytometry were derivatized with glutathione. A fusion protein of GST and green fluorescent protein was used to define kinetic and equilibrium binding characteristics of GST fusion proteins to glutathione beads. Free glutathione competes with this binding, and this competition was used to measure free glutathione concentration.

Results:

A 10 μl assay can measure 5 μl of 20 μM glutathione (100 pmol glutathione) in 2 h by flow cytometry. This concentration is two orders of magnitude lower than cellular glutathione concentrations, and three orders of magnitude lower than affinity chromatography eluates. One important result is that by generating high site density, the GST fusion proteins can be constrained to the surface of one bead without hopping to the next bead in multiplex assays.

Conclusions:

Glutathione in cellular lysates and GST‐fusion protein affinity chromatography eluates can be measured by flow cytometry. Many interactions between GST fusion proteins and their fluorescent binding partners should be quantifiable by flow cytometry. Although a system may have the disadvantage that it has a low affinity and a correspondingly quick off‐rate in solution, it may remain on beads if the site density can be increased to offer a slow apparent off rate. © 2006 International Society for Analytical Cytology
Is bacterial vaginosis associated with squamous intraepithelial lesion of the uterine cervix?
Authors: Discacciati Michelle G. , Simoes Jose A. , Lopes Erika S. , Silva Samara M. , Montemor Eliana B.L. , Rabelo‐Santos Silvia H. , Westin Maria C.A.
Published: April 2006

The objective of this study was to analyze the association between bacterial vaginosis (BV) and squamous intraepithelial lesion (SIL). Pap smears were analyzed to verify the presence of BV and SIL. One hundred and ten women with SIL comprised the study group, while 110 women with no cytological abnormalities served as controls. BV was similarly present in women of both groups: 18% of women with SIL and 12% of women without SIL. Results were also similar when the grade of SIL was taken into consideration. BV was detected in 16% of women with low‐grade SIL and in 12% of women in the control group, while a higher rate of BV (33%) was found among women with high‐grade SIL in comparison to the controls (12%). This difference, however, was not statistically significant. BV tended to be more common among women with high‐grade SIL than in women with no cytological abnormalities. Diagn. Cytopathol. 2006; 34:323–325. © 2006 Wiley‐Liss, Inc.
Transgenic mouse for conditional, tissue‐specific Cox‐2 overexpression
Authors: Kamei Ken‐ichiro , Ishikawa Tomo‐o , Herschman Harvey R.
Published: April 2006

We constructed a cyclooxygenase‐2 (Cox‐2) conditional overexpression transgenic mouse (Cox‐2 COE). The transgene contains a CAG promoter driving the Cox‐2 and humanized Renilla luciferase (hRL) coding regions, linked by an internal ribosomal entry site. The promoter is followed by a loxP‐flanked sequence containing enhanced green fluorescent protein (EGFP), a neomycin selection cassette, and a transcriptional/translational STOP sequence. In the presence of Cre recombinase the loxP‐flanked sequence is excised. Cox‐2/hRL expression can be monitored repeatedly and noninvasively in vivo by imaging hRL activity. To demonstrate conditional Cox‐2 and hRL expression, a nonreplicating adenovirus carrying Cre recombinase (Ad.CMV.Cre) was injected intravenously; hepatic Cox‐2 expression and hRL signal were elevated. Cox‐2 COE embryonic fibroblasts express both Cox‐2 and hRL following Ad.CMV.Cre infection. PGE2 production is also increased following Ad.CMV.Cre infection of Cox‐2 COE embryo fibroblasts. Cox‐2 COE mice should be valuable for the study of Cox‐2 overexpression in cardiovascular disease, acute and chronic inflammatory responses, neurodegenerative diseases, and cancer. genesis 44:177–182, 2006. Published 2006 Wiley‐Liss, Inc.
Determination of thiol compounds by automated headspace solid‐phase microextraction with in‐fiber derivatization
Authors: Wang Qing , Chong J. Michael , Pawliszyn Janusz
Published: April 2006

In this article, headspace solid‐phase microextraction (HS‐SPME) analysis of thiol compounds with both solid and aqueous samples was investigated using N‐phenylmaleimide as an in‐fiber derivatization reagent. The derivatives were analyzed using GC‐MS. The HS‐SPME method was executed on an automatic sampler and optimized by studying a variety of factors such as the selection of the fiber, extraction time, temperature, agitation speed, etc. Method validation was carried out by spiking known amounts of thiol compounds into the sample and calculating the concentration by standard addition. The relative standard deviations (RSD) for the majority of the thiols were less than 10%. The developed method resulted in a limit of detection (LOD) in the low microgram per liter for most of the thiols analyzed, which was about one order of magnitude lower than the HS‐SPME without derivatization. Finally, the overall method was successfully applied for the determination of thiols in yellow onion, green onion and garlic. Copyright © 2006 John Wiley & Sons, Ltd.
Enzyme‐catalyzed regioselective synthesis of sugar esters and related compounds
Authors: Kennedy John F , Kumar Harish , Panesar Parmjit S , Marwaha Satwinder S , Goyal Rita , Parmar Anupama , Kaur Sukhwinder
Published: April 2006

In this review, a comprehensive and illustrative survey is made of the regioselective synthesis of esters of sugars and related compounds using lipases. The main emphasis has been given to the screening and use of commercially available lipases for the enzymatic esterification of neutral monosaccharides, disaccharides, sugar alcohols and their selected ether and ester derivatives. The effect of solvents and solubilizing agents in improving the yields of the resultant sugar fatty acid esters has been incorporated. Further, solvent‐free esterification with molten fatty acids, use of ionic liquids and microwave radiations for improvement in the methodology have also been discussed. Copyright © 2006 Society of Chemical Industry
Machine learning approaches for prediction of linear B‐cell epitopes on proteins
Authors: Söllner Johannes , Mayer Bernd
Published: April 2006

Identification and characterization of antigenic determinants on proteins has received considerable attention utilizing both, experimental as well as computational methods. For computational routines mostly structural as well as physicochemical parameters have been utilized for predicting the antigenic propensity of protein sites. However, the performance of computational routines has been low when compared to experimental alternatives.

Here we describe the construction of machine learning based classifiers to enhance the prediction quality for identifying linear B‐cell epitopes on proteins. Our approach combines several parameters previously associated with antigenicity, and includes novel parameters based on frequencies of amino acids and amino acid neighborhood propensities. We utilized machine learning algorithms for deriving antigenicity classification functions assigning antigenic propensities to each amino acid of a given protein sequence. We compared the prediction quality of the novel classifiers with respect to established routines for epitope scoring, and tested prediction accuracy on experimental data available for HIV proteins. The major finding is that machine learning classifiers clearly outperform the reference classification systems on the HIV epitope validation set. Copyright © 2006 John Wiley & Sons, Ltd.
Do senior management development programmes enhance strategic management capabilities?
Authors: Brown Paul
Published: April 2006

The potential that management development programmes designed for senior managers have for contributing to the strategic management capabilities of organizations is explored through a survey of such programmes in large UK companies.

The programmes are found to be able to contribute to strategy formulation and implementation, including the management of change, as well as helping to develop strategic management competencies in participants. Areas where programmes often under‐achieve and opportunities for their enhancement are identified.

Copyright © 2006 John Wiley & Sons, Ltd.
Spinning on dimes: the challenges of introducing transformational change into the UK Ministry of Defence
Authors: Neal Derrick , Taylor Trevor
Published: April 2006

The UK Ministry of Defence (MoD) continues to be a significant customer for the major management consultancies proclaiming their expertise in change management. This paper assesses the degree to which change is being delivered effectively within the MoD and in particular within the business space.

The paper finds, based on a mixture of primary and secondary data, that the complexities of the MoD are working against the successful delivery of change in a number of ways including: civil servants and military staff needing to have a much deeper understanding of the subject of change management; deficiencies in establishing the necessary sense of urgency for change in the business space; and a failure to make the distinction between incremental and transformational change, leading to unrealistic expectations of the time required to deliver change.

The paper also notes that failures in the delivery of change in the business space will ultimately lead to important shortcomings in military operations.

Copyright © 2006 John Wiley & Sons, Ltd.
Aqueous chromatography system using temperature‐responsive polymer‐modified stationary phases
Authors: Ayano Eri , Kanazawa Hideko
Published: April 2006

Extensive research has been carried out on functional polymers which are currently playing important roles in various fields such as medicine and engineering. Such functional polymers which respond to various kinds of stimuli are termed ‘intelligent materials’. Poly(N‐isopropylacrylamide) (PNIPAAm), a temperature‐responsive polymer, was utilized as a chromatography column matrix modifier for a novel chromatographic approach in which only aqueous media are used as a mobile phase. The ability of the developed temperature‐responsive chromatography system to separate solutes without using an organic solvent is advantageous from the point of view of maintaining the structure and activity of bioactive compounds. Recently, we designed and synthesized a new pH‐ and temperature‐responsive copolymer as a representative of such environment‐responsive polymers and grafted it onto aminopropyl silica beads. The products were evaluated as HPLC packing materials for separation systems based on a new concept, according to which the properties of the stationary phase surface are altered by external stimuli such as pH and temperature. This chromatography system utilizing the PNIPAAm copolymer is very useful for the separation of bioactive substances, such as proteins and peptides, because separation in the aqueous mobile phase is controlled solely by changing the temperature. This analytical system reduces organic waste because no organic solvent is used to separate the solutes and can therefore be classified as environmentally friendly. Future medical and pharmaceutical applications are expected.
Retention and selectivity tests of silica‐based and metal‐oxide bonded stationary phases for RP‐HPLC
Authors: Jandera Pavel , Novotná Kateřina , Beldean‐Galea Mihail S. , Jíša Kamil
Published: April 2006

Chromatographic properties of silica‐, zirconia‐ and alumina‐based columns with octadecyl‐, polyethylene glycol‐ and pentafluorophenylpropyl‐bonded stationary phases were tested. Selectivities of nine columns for LC were characterized using chromatographic methods including Walters, Engelhardt, Tanaka and Galushko hydrophobicity and silanol activity tests, measurements of methylene selectivity in various aqueous‐methanol and aqueous‐acetonitrile mobile phases and of gradient lipophilic capacity as a measure of the effect of the sample hydrophobicity on gradient‐elution separations. A semi‐empirical interaction indices model, assuming a predominant role of the solvophobic interactions of test compounds with different polarities, was compared with the linear free energy relationships approach taking into account selective polar interactions. The interaction indices model was applied to both non‐polar stationary phases bonded on silica, alumina and zirconia supports, and to the non‐modified adsorbents in the normal‐phase LC. The retention data of isomeric naphthalene disulfonic acids were used to compare the attractive and repulsive ionic interactions of the columns in purely aqueous mobile phases. The results of the hydrophobicity and polarity tests were consistent, and allowed column characterization and classification. Silanol activity was important with octadecyl silica columns, but was relatively insignificant with bonded polyethylene glycol and pentafluorophenylpropyl phases on silica gel support. Polar interactions with the alumina and zirconia support materials significantly affect the retention.
New engine coolant for corrosion protection of magnesium alloys
Authors: Starostin M. , Tamir S.
Published: April 2006

The global trend toward decreasing of atmospheric pollution, by saving fuel consumption in vehicles, has led to extensive interest of using lightweight metals such as magnesium alloys, in engine and cooling system components. The modern coolant is not intended to prevent corrosion of magnesium alloy in the engine cooling systems. We have developed a new coolant that aims to protect Mg alloy parts together with all other commonly used metals. Several inhibitor formulations were tested, according to glassware test (ASTM D1384) and heat transfer conditions (ASTM D4340). Mg alloys EZ33 and WE43 were added to the standard sets of metals and the corrosivity of different types of formulations was determined by weight loss measurements. The new anticorrosive coolant showed high performance in all tested metals including magnesium alloys and it satisfied the requirements (ASTM D3306). Cyclic potentiodynamic polarization curves have been used to study electrochemical corrosion behavior of the magnesium alloys EZ33 and WE43 in aqueous solution containing the inhibitors and ethylene glycol (33 vol%‐EG prepared with corrosive water according to ASTM D1384) and compared to a reference coolant with no inhibitor. It was found that a passive film was created upon the Mg alloys, which exhibited high corrosion resistance against pitting.
Testing procedure to obtain reliable potentiodynamic polarization curves on type 310S stainless steel in alkali carbonate melts
Authors: Frangini S.
Published: April 2006

Potentiodynamic polarization measurements have been employed to evaluate the anodic behavior of a type 310S stainless steel in the eutectic Li/K molten carbonate. In general, the electrochemical tests yield useful information to predict the stability of the oxide films formed on the surface at the initial period of corrosion, although some precaution is required in the testing procedure as the reproducibility of results is seen to be adversely affected by the passage of large currents. Especially when the steel is in a passive state, erratic results are easily observed if the corrosion layer is being damaged by uncontrolled large currents. This is because the acid‐base properties of the melt are susceptible to deep changes by applied currents in the milli‐ampere range resulting in hysteresis phenomena in the polarization plot. Hysteresis is caused, on one hand, by acidic dissolution of the passive layer at high anodic currents and, on the other hand, by increased melt basicity due to oxide ion build‐up at high cathodic currents. An optimized testing procedure is therefore suggested that minimizes these effects by imposing a 2 mA/cm2 threshold current during polarization measurements. Moreover, the conditions for the applicability of the linear polarization technique to estimate kinetic parameters have been discussed in relationship with the corrosion mechanisms analysed by impedance spectra. It is concluded that the presence of diffusional impedance terms and formation of surface resistive films in molten carbonates may result in not reliable polarization resistance values obtained with the linear polarization.
Nucleoplasmin facilitates reprogramming and in vivo development of bovine nuclear transfer embryos
Authors: Betthauser Jeffery M. , Pfister‐Genskow Martha , Xu Hongzhi , Golueke Paul J. , Lacson Jenine C. , Koppang Richard W. , Myers Cena , Liu Bing , Hoeschele Ina , Eilertsen Kenneth J. , Leno Gregory H.
Published: April 2006

Successful cloning by somatic cell nuclear transfer (NT) involves an oocyte‐driven transition in gene expression from an inherited somatic pattern, to an embryonic form, during early development. This reprogramming of gene expression is thought to require the remodeling of somatic chromatin and as such, faulty and/or incomplete chromatin remodeling may contribute to the aberrant gene expression and abnormal development observed in NT embryos. We used a novel approach to supplement the oocyte with chromatin remodeling factors and determined the impact of these molecules on gene expression and development of bovine NT embryos. Nucleoplasmin (NPL) or polyglutamic acid (PGA) was injected into bovine oocytes at different concentrations, either before (pre‐NT) or after (post‐NT) NT. Pre‐implantation embryos were then transferred to bovine recipients to assess in vivo development. Microinjection of remodeling factors resulted in apparent differences in the rate of blastocyst development and in pregnancy initiation rates in both NPL‐ and PGA‐injected embryos, and these differences were dependent on factor concentration and/or the time of injection. Post‐NT NPL‐injected embryos that produced the highest rate of pregnancy also demonstrated differentially expressed genes relative to pre‐NT NPL embryos and control NT embryos, both of which had lower pregnancy rates. Over 200 genes were upregulated following post‐NT NPL injection. Several of these genes were previously shown to be downregulated in NT embryos when compared to bovine IVF embryos. These data suggest that addition of chromatin remodeling factors to the oocyte may improve development of NT embryos by facilitating reprogramming of the somatic nucleus. Mol. Reprod. Dev. 977dash;986, 2006 © 2006 Wiley‐Liss, Inc.
Flame retardancy of nanocomposites based on organoclays and carbon nanotubes with aluminium trihydrate
Authors: Beyer Günter
Published: April 2006

The addition of aluminium trihydrate as a microfiller to organoclays or carbon nanotubes is essential to generate nanocomposites with sufficient flame retardant properties as requested by the industry. Cables using the combination of organoclays or carbon nanotubes and aluminium trihydrate demonstrate the applications of these nanocomposites as a new concept for flame retardancy. Copyright © 2006 John Wiley & Sons, Ltd.
Acrylonitrile‐containing polymers via a combination of metal‐catalyzed living radical and nitroxide‐mediated free‐radical polymerization routes
Authors: Ilhanli Ozlenen B. , Erdogan Tuba , Tunca Umit , Hizal Gurkan
Published: April 2006

2‐Phenyl‐2‐[(2,2,6,6‐tetramethylpiperidino)oxy] ethyl 2‐bromopropanoate was successfully used as an initiator in consecutive living radical polymerization routes, such as metal‐catalyzed living radical polymerization and nitroxide‐mediated free‐radical polymerization, to produce various types of acrylonitrile‐containing polymers, such as styrene–acrylonitrile, polystyrene‐b‐styrene–acrylonitrile, polystyrene‐b‐poly(n‐butyl acrylate)‐b‐polyacrylonitrile, and polystyrene‐b‐polyacrylonitrile. The kinetic data were obtained for the metal‐catalyzed living radical polymerization of styrene–acrylonitrile. All the obtained polymers were characterized with 1H NMR, gel permeation chromatography, and differential scanning calorimetry. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3374–3381, 2006
High thermal conductivity of polymerizable liquid‐crystal acrylic film having a twisted molecular orientation
Authors: Kato Takashi , Nagahara Takatoshi , Agari Yasuyuki , Ochi Mitsukazu
Published: April 2006

The aligned films, the homogeneous film, the 90°‐twisted film and the 180°‐twisted film, have been prepared by immobilizing the polymerizable liquid crystals under the UV irradiation. The relation between the thermal conductivity and the aligned molecular direction of the films was investigated. It is indicated that the additional thermal transmission effect, which the increase of the thermal conductivity may be induced, would exist in the twisted films. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1419–1425, 2006
Mechanical behaviour of ultrafine grained aluminium containing Al8Fe2Si precipitates
Authors: Korchef A. , Kolsi A. W. , Njah N.
Published: April 2006

A 99.1% aluminium was deformed by Equal Channel Angular (ECA) pressing. The material contains a low volume fraction of Al8Fe2Si precipitates located essentially at the grain boundaries. An important increase of the X‐ray diffraction peak broadening was observed after ECA pressings. This is due to grain refinement and enhanced lattice distortions. This was accompanied by a lattice decrease due to compressive stresses and partial dissolution of the Al8Fe2Si precipitates. The grain refinement leads to a significant improvement of the mechanical properties in compression and tension after the first pass through the die. Thereafter, the increase was less significant. The strengthening of the material was accompanied by decreased strain hardening, due to enhanced activities in grain boundaries. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The mystery of youth leadership development: The path to just communities
Authors: Libby Margaret , Sedonaen Maureen , Bliss Steven
Published: April 2006

Some of the mystery around the meaning of youth leadership development, and around what youth leadership means for youth development, can be solved by accounting for the potential connections, as well as the potential tensions and conflicts, between the Inside and Outside approaches.
Leading, learning, and unleashing potential: Youth leadership and civic engagement
Authors: Wheeler Wendy , Edlebeck Carolyn
Published: April 2006

The Innovation Center for Community and Youth Development is a Washington, D.C.‐based organization engaged in programming, research, and policy development related to youth civic engagement. Its mission is to unleash the potential of youth, adults, organizations, and communities to engage together in creating a just and equitable society.
Glycolytic sequence and respiration of Debaryomyces hansenii as compared to Saccharomyces cerevisiae
Authors: Sánchez N. S. , Calahorra M. , González‐Hernández J. C. , Peña A.
Published: April 2006

The fermentation and respiration activities of Debaryomyces hansenii were compared with those of Saccharomyces cerevisiae grown to stationary phase with high respiratory activity. It was found that: (a) glucose consumption, fermentation and respiration were lower than for S. cerevisiae; (b) fasting produced a much smaller decrease of respiration; (c) glucose consumed and not transformed to ethanol was higher; (d) in S. cerevisiae, full oxygenation prevented ethanol production but this effect was reversed by CCCP, whereas D. hansenii still showed some ethanol production under aerobiosis, which was moderately increased by CCCP. ATP levels were similar in the two yeasts. Levels of glycolytic intermediaries after glucose addition, and enzyme activities, indicated that the main difference and limiting step to explain the lower fermentation of D. hansenii is phosphofructokinase activity. Respiration and fermentation, which are lower in D. hansenii, compete for the re‐oxidation of reduced nicotinamide adenine nucleotides; this competition, in turn, seems to play a role in defining the fermentation rates of the two yeasts. The effect of CCCP on glucose consumption and ethanol production also indicates a role of ADP in both the Pasteur and Crabtree effects in S. cerevisiae but not in D. hansenii. D. hansenii shows an alternative oxidase, which in our experiments did not appear to be coupled to the production of ATP. Copyright © 2006 John Wiley & Sons, Ltd.
Involvement of yeast YOL151W/GRE2 in ergosterol metabolism
Authors: Warringer Jonas , Blomberg Anders
Published: April 2006

The Saccharomyces cerevisiae gene YOL151W/GRE2 is widely used as a model gene in studies on yeast regulatory responses to osmotic and oxidative stress. Nevertheless, information concerning the physiological role of this enzyme, a distant homologue of mammalian 3‐β‐hydroxysteroid dehydrogenases, is scarce. Combining quantitative phenotypic profiling and protein expression analysis studies, we here report the involvement of yeast Gre2p in ergosterol metabolism. Growth was significantly and exclusively reduced in gre2Δ strains subjected to environmental stress straining the cell membrane. Furthermore, whereas no compensatory mechanisms were activated due to loss of Gre2p during growth in favourable conditions (synthetic defined media, no stress), a striking and highly specific induction of the ergosterol biosynthesis pathway, represented by the enzymes Erg10p, Erg19p and Erg6p, was observed in gre2Δ during growth in a stress condition in which lack of Gre2p significantly affects growth. Involvement of Gre2p in ergosterol metabolism was confirmed by application of an array of selective inhibitors of lipid biosynthesis, as gre2Δ displayed vastly impaired tolerance exclusively to agents targeting the ergosterol biosynthesis. The approach outlined here, combining broad‐spectrum phenotypic profiling, expression analysis during conditions reducing the growth of the mutant and functional confirmation by application of highly selective inhibitors, may prove a valuable tool in gene functional analysis. Copyright © 2006 John Wiley & Sons, Ltd.
PCR‐mediated seamless gene deletion and marker recycling in Saccharomyces cerevisiae
Authors: Akada Rinji , Kitagawa Takao , Kaneko Shohei , Toyonaga Daiso , Ito Sachiko , Kakihara Yoshito , Hoshida Hisashi , Morimura Shigeru , Kondo Akihiko , Kida Kenji
Published: April 2006

Repeated gene manipulations can be performed in yeast by excision of an introduced marker. Cassette modules containing a marker flanked by two direct repeat sequences of hisG or loxP have often been used for marker recycling, but these leave one copy of the repeats in the chromosome after excision. Genomic copies of a repeat can cause increased mistargeting of constructs containing the same repeats or unexpected chromosomal rearrangements via intra‐ or interchromosomal recombinations. Here, we describe a novel marker recycling procedure that leaves no scar in the genome, which we have designated seamless gene deletion. A 40 base sequence derived from an adjacent region to the targeted locus was placed in an integrating construct to generate direct repeats after integration. Seamless HIS3 deletion was achieved via a PCR fragment that consisted of a URA3 marker attached to a 40 base repeat‐generating sequence flanked by HIS3 targeting sequences at both ends. Transformation of the designed construct resulted in his3 disruption and the generation of 40 base direct repeats on both sides of URA3 in the targeted locus. The resulting his3::URA3 disruptants were plated on 5‐fluoroorotic acid medium to select for URA3 loss. All the selected colonies had lost URA3 precisely by recombination between the repeats, resulting in his3 deletion without any extraneous sequences left behind in the chromosome. Copyright © 2006 John Wiley & Sons, Ltd.
Different effects of sphingid and noctuid moths on the fecundity of Platanthera metabifolia (Orchidaceae) in Hokkaido
Authors: Inoue Ken
Published: April 2006

The fecundity of Platanthera metabifolia was investigated in relation to different types of behavior and morphology in both noctuid and sphingid pollinator moths. Low capsule set in the native habitats resulted from low activity of pollinating moths. From different patterns of capsule formation on spikes, pollinated spikes could be classified into sphingid‐pollinated and noctuid‐pollinated types. The contributions of sphingids to capsule set were nearly constant at the three study sites. High percentage capsule set at one site was linked with high noctuid activity. Different preferences of sphingids and noctuids as to spike features were detected: sphingids selected spikes with large numbers of flowers in early stages of flowering. Flowers with different spur length were equally pollinated by sphingids. On the other hand, noctuids selected spikes with short and medium‐sized spurs in the late stage of flowering. The size and density of spikes scarcely affected the pollination activity of noctuids. Selection pressure upon spike size and spur length in relation to sphingid pollination was suggested. The possibility of local differentiation in spur length due to activity of noctuids was discussed.
Cycling of soil carbon in a Japanese red pine forest II. Changes occurring in the first year after a clear‐felling
Authors: Nakane Kaneyuki , Tsubota Hiroyuki , Yamamoto Makoto
Published: April 2006

Cycling of soil carbon in the first year after a clear‐felling was compared with that before the felling in a Japanese red pine forest in Hiroshima Prefecture, west Japan. The daily mean temperature at the soil surface in summer was increased after the felling in comparison to that before felling, and the water content of both the A0 layer and the surface mineral soil was decreased due to the loss of the forest canopy. The rate of weight loss of the A0 layer was reduced after felling. However, accumulation of the A0 layer rapidly decreased because of the lack of litter supply to the forest floor. Low soil respiration after felling was mainly caused by the cessation of root respiration. Analysis of annual soil carbon cycling was then conducted using a compartment model. The relative decomposition rate of the A0 layer decreased whereas that of humus and dead roots in mineral soil increased to some extent after felling. The accumulation of carbon in mineral soil, however, increased slightly due to the supply of humus from roots killed by the felling.