bluuebunny/crossref_metadata_2025_split huggingface dataset:
To Be Dinuclear or Not: Z‐DNA Induction by Nickel Complexes
Authors: Spingler Bernhard , Antoni Philipp M. 
Published: May 2007

AbstractThe left‐handed Z‐DNA has been identified as a gene regulating element. Therefore the generation of Z‐DNA through metal complexes might be an innovative way for the regulation of gene expression. Use of the new dinuclear complex N,N,N′,N′‐tetrakis‐[2‐(3,5‐dimethylpyrazol‐1‐yl)ethyl]‐1,3‐propylenediamine‐bis(nickel(II) dinitrate) (2) reversibly induced Z‐DNA formation. However, when a 1:1 ratio of metal/dinucleating ligand was used as a control, the midpoint of the B‐ to Z‐DNA transition was at the same nickel concentration as in case of the dinuclear complex. The novel mononuclear analogue, N‐methyl‐N,N‐bis‐[2‐(3,5‐dimethylpyrazol‐1‐yl)ethyl]amine‐nickel(II)‐dinitrate (3) was inducing the Z‐DNA at a similar ratio versus nucleotides as free nickel(II) itself. For the first time, proton and nickel binding constants for the bis‐[2‐(pyrazol‐1‐yl)ethyl]amine ligand system are reported and discussed. Both nickel complexes 2 and 3 were structurally characterized by single crystal analysis. Furthermore, the synthesis of the two new ligands, N,N,N′,N′‐tetrakis‐[2‐(3,5‐dimethylpyrazol‐1‐yl)ethyl]‐1,2‐propylenediamine (4) and N‐methyl‐N,N‐bis‐[2‐(3,5‐dimethylpyrazol‐1‐yl)ethyl]amine (5) is described. The two major synthetic pathways leading to polypyrazoyl amines in general are critically discussed with respect to yield, reproducibility and handling of the intermediates.
Updating meshes on deforming domains: An application of the target‐matrix paradigm
Authors: Knupp Patrick 
Published: May 2007

AbstractA method for updating meshes in response to domain deformation is formulated within the target‐matrix mesh optimization paradigm. By casting the problem within this paradigm, various formulations of the problem can be considered. Two local metrics are suggested for use in a multi‐variable objective function to update meshes via numerical optimization. Both guarantee that if the deformation is null, the original mesh on the un‐deformed domain will be replicated. Further, target matrices are constructed in a manner that ensures the updated mesh is as similar to the un‐deformed mesh as possible. Numerical experiments confirm these properties on 2D examples. The update method has limitations, of course, the most important being that there is no guarantee that the deformed mesh will be invertible. Published in 2007 by John Wiley & Sons, Ltd.
A Density Functional Study of the Factors That Influence the Regioselectivity of Toluene Hydroxylation by Cytochrome P450 Enzymes
Authors: Hazan Carina , Kumar Devesh , de Visser Sam P. , Shaik Sason 
Published: May 2007

AbstractDensity functional theory calculations have been performed to elucidate the factors that influence the regioselectivity of toluene hydroxylation by a model of the active species of cytochrome P450 enzymes, so‐called Compound I (Cpd I). Cpd I can hydroxylate the benzylic C–H and generate benzyl alcohol, or it can activate the phenyl group and produce p‐cresol and p‐methylcyclohexanone products. The reactions take place via two‐state reactivity on competing doublet and quartet spin state surfaces. In the gas phase, the benzyl alcohol is preferred over p‐cresol by more than three orders of magnitude. Environmental perturbations, namely, NH···S hydrogen bonding to the thiolate ligand and bulk polarity of the protein, lower this preference to roughly 10:1 in favour of benzyl alcohol. Substitution of methyl hydrogen atoms by deuterium atoms raises the barriers that lead to benzyl alcohol without affecting those leading to p‐cresol. Therefore combining toluene deuteration with the effects of NH···S hydrogen bonding and bulk polarity lowers the free energy difference between the two processes to only 0.4 kcal mol–1, and the two processes become competitive. These results as well as the calculated kinetic isotope effects are in good general agreement with experimental data. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Tetranuclear Nickel Complexes Composed of Pairs of Dinuclear LNi2 Fragments Linked by 4,4′‐Bipyrazolyl, 1,4‐Bis(4′‐pyrazolyl)benzene, and 4,4′‐Bipyridazine: Synthesis, Structures, and Magnetic Properties
Authors: Lozan Vasile , Solntsev Pavlo Y. , Leibeling Guido , Domasevitch Konstantin V. , Kersting Berthold 
Published: May 2007

AbstractThe ability of the ligands 4,4′‐bipyrazolyl (H2bpz), 1,4‐bis(4′‐pyrazolyl)benzene (H2bpzb), and 4,4′‐bipyridazine (bpdz) to link two dioctahedral LNi2 units has been examined. Thefollowing complexes were prepared: [L1NiII2(Hbpz)][BPh4] (6[BPh4]), [L1NiII2(bpdz)][ClO4]2 (7[ClO4]2), [(L1NiII2)2(bpzb)][BPh4]2 (8[BPh4]2), and [(L2NiII2)2(bpz)][BPh4]2 (9[BPh4]2), where (L1)2– and (L2)2– represent macrocyclic hexaaza‐dithiophenolate ligands. All complexes have been characterised by UV/Vis spectroscopy, IR spectroscopy, and X‐ray crystallography. Whereas (Hbpz)– and bpdz in 6[BPh4]2 and 7[ClO4]2 act as bidentate ligands coordinating to only one [LNi2]2+ unit, in 8[BPh4]2 and 9[BPh4]2 the (bpzb)2– and(bpz)2– units are tetradentate linkers. This is qualitatively explained in terms of the absence or presence of steric repulsions between the tBu groups of the supporting ligands and the length of the coligands. The structures of the tetranuclear complexes differ mainly in the distance between the center of the Ni···Ni axes of the isostructural [LNi2] units {14.040(1) Å in 8[BPh4]2, 9.184(1) Å in 9[BPh4]2}. The two Ni2pyrazolato planes in 9[BPh4]2 are coplanar. An analysis of the temperature‐dependent magnetic susceptibility data for 9[BPh4]2 reveals the presence of weak ferromagnetic exchange interactions between the NiII ions in the binuclear [L2Ni2] subunits with values for the magnetic exchange constant J1 of 23.97 cm–1 (H = –2JS1S2). The exchange coupling across the dipyrazolato bridge is less than 0.1 cm–1, suggesting that no significant interdimer exchange coupling occurs in 9[BPh4]2. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
An Approach to Enantioselective 5‐endo Halo‐Lactonization Reactions
Authors: Garnier Jean Marc , Robin Sylvie , Rousseau Gérard 
Published: May 2007

AbstractEnantioselective lactonization of 4‐substituted but‐3‐enoic acids using iodobis(N‐methylephedrine) hexafluoroantimonate in dichloromethane at low temperatures is reported. The presence of bis(N‐methylephedrine)silver(I) hexafluoroantimonate, derived from the excess amounts of N‐methylephedrine and silver hexafluoroantimonate that were necessary for the generation of the iodo complex in the reaction mixture, is crucial for the success of this reaction. The different parameters of these cyclization reactions have been examined. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Squarrosidine and Pinillidine: 3,3′‐Fused Bis(styrylpyrones) from Pholiota squarrosa and Phellinus pini
Authors: Kemami Wangun Hilaire V. , Hertweck Christian 
Published: May 2007

AbstractTwo novel fungal phenylpropanoid‐derived polyketides, squarrosidine (8) and pinillidine (9), with potent xanthine oxidase (XO) inhibitory activities were isolated from the fruiting bodies of the mushroom Pholiota squarrosa and from the mycelium of Phellinus pini by bioassay‐guided isolation. Structural analyses revealed that both metabolites from the tree fungi represent unprecedented 3,3′‐fused bis(styrylpyrones). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis and Photophysical Properties of Some Rigidized Hepta‐ and Nonamethine Mono‐ and Bis(merocyanines): Ring‐Opening of Quaternized 2‐Methylbenzothiazole
Authors: Viteva Lilia , Gospodova Tzveta , Rashkova Jivka , Abrahams Isaac , Timtcheva Iliana , Simova Svetlana , Mazieres Marie Rose , Wolf Jean Gérard 
Published: May 2007

AbstractWe have developed a simple and efficient method for the synthesis of rigidized mono‐ and bis‐heptamethine merocyanines that contain one methine unit incorporated into a cyclopentene framework. The synthetic approach is based on C1/C5 regioselective nucleophilic addition of mono‐ and diketone lithium enolates to readily available pentamethine cyanines with inherent rigidity followed by a Hofmann elimination reaction. The new dyes react easily with heterocyclic benzothiazolium compounds containing an activated methyl group. Depending on the reaction conditions one or two reactive centres can be attacked, thus giving access to new merocyanine derivatives with a lengthened polymethine chain and/or ramified by a second heterocyclic unit. X‐ray crystallographic analysis reveals that the second heterocycle is incorporated via a sulfur bridge as a result of the opening of the benzothiazole ring. All new compounds were fully characterized by 1D and 2D NMR spectroscopic techniques (1H, 13C, DEPT, COSY, NOESY, HSQC with and without decoupling, HMBC). Their photophysical properties have been studied and correlated with solvent polarities. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Pollen morphology, leaf surfaces, mycobiota diversity and leaf spots of three species ofZygophyllumgrowing along Cairo‐Suez desert road, Eastern (Arabian) desert in Egypt
Authors: El Naggar S. M. , Abdel‐Hafez S. I. I. 
Published: May 2007

AbstractThree native species ofZygophyllum:Z. coccinumL.,Z. decumbensL.and Z. simplexL. (Zygophyllaceae) have been investigated morphologically, palynologically and mycologically. Twenty‐two fungal species belonging to 11 genera were collected from leaf surfaces (11 genera and 22 species) and anthers/ pollen grains (7, 13) ofZygophyllum coccinum, Z. decumbens and Z. simplexon Czapek‐Dox agar at 25 °C. Fungal diversity of the two microhabitats is basically similar and the most prevalent fungi wereAlternaria alternata/A. phragmospora, Cladosporium cladosporioides/C. herbarumandUlocladium botrytis/U. consortiale.Alternaria alternata,Cladosporium cladosporioidesandC. herbarum‐leaf spots were rarely recorded in the three studied plant species.Leaf lamina size and sculpture of the studied taxa almost seem to be the most reliable factors of the fungal biodiversity on the studied plant species. On the other hand, reticulate‐micro reticulate pollen type is the only pollen type recorded in the present study which reflects that the very narrow range of spectrum of fungal biodiversity between the studied plant species. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of Operation, Energy Savings, and CO2 Balance of a Domestic Fuel Cell Energy Center
Authors: Pawlik J. , Klaschinsky H. , Dippel R. , Mlynski M. , Hlawenka A. , Denneberg V. 
Published: May 2007

AbstractSystem simulations are performed in order to calculate the economic efficiency of a PEM fuel cell system. The simulation model is developed using the well‐established MATLAB/Simulink platform. The major input parameters are measured data for the heat and power consumption of a detached house with a conventional heating system and Fuel Cell Energy Center design parameters.The simulation compares the house with a conventional heating system with electrical power supplied by the grid to the same house with a cogeneration fuel cell heating system. The natural gas consumption and the electrical power consumption of the house are analyzed for both systems. Furthermore, the reduction in the CO2 emissions is calculated. Calculations are made for summer, winter, autumn, and spring, to investigate the influence of the seasons.
The human resource potential of Americans over 50
Authors: McNaught William , Barth Michael C. , Henderson Peter H. 
Published: May 2007

AbstractThis article analyzes whether many Americans over age 50 want to return to work. It estimates that among males ages 55 to 64 and females ages 50 to 59 currently not working 1.1 million persons are ready and able to work, have substantial skills and education, would work in high demand occupations, and are flexible about conditions of employment.
A practical but theory‐based framework for selecting cross‐cultural training methods
Authors: Black J. Stewart , Mendenhall Mark 
Published: May 2007

AbstractIncreased internationalization in the economic, political, and social arenas has led to greater interpersonal cross‐cultural contact. Because much of this contact has not been successful, cross‐cultural training has been proposed by many scholars as a means of facilitating more effective interaction. However, most firms do not utilize cross‐cultural training. The cross‐cultural training framework proposed in this article is based on both theory and a review of the cross‐cultural training literature. The contingency framework proposed provides a practical guide for determining the method and rigor of cross‐cultural training most effective in various circumstances.
Affirmative action: Federal support, supreme court decisions, and human resource management
Authors: Marlow Edward K. , Rowland Kendrith M. 
Published: May 2007

AbstractThis article explores the historical background of affirmative action in the United States, and reviews haw federal support for it has changed since the Civil War. Several recent US Supreme Court cases deciding affirmative action issues are discussed, with speculation about the future of affirmative action in light of these decisions. The article also discusses the implications of these rulings for human resource practitioners.
When organizational relocation means family relocation: An emerging issue for strategic human resource management
Authors: Lawson Marian B. 
Published: May 2007

AbstractRelocations of entire organizational units raise special family adjustment issues. This article reports on the reactions of employees and their families to such a relocation. Employees' adjustment was more strongly related to nonwork and family impacts of the move than to factors in the workplace. Adjustment was more difficult for families inexperienced in relocation, despite extensive company assistance programs.
Outside director compensation and firm performance
Authors: Hempel Paul , Fay Charles 
Published: May 2007

AbstractCompensation given to outside directors has come under increasing scrutiny. However, little empirical work exists which examines outside director compensation. A study of more than 225 major corporations over a five‐year period indicates that the number of board meetings and the size of the company are major factors in outside director compensation levels, while organization performance and Chief Executive Officer remuneration do not appear to be significantly related. These findings suggest that market‐driven compensation systems are the dominant form used by large organizations to pay outside directors, with a major goal being the attraction and retention of these directors.
Better practices in managing layoffs
Authors: Feldman Daniel C. 
Published: May 2007

AbstractThis article presents eight case studies that illustrate “better practices” in how layoffs are managed in organizations. These examples incorporate such policies and programs as early notification of layoffs, provisions for severance pay and extended benefits, education and retraining for displaced workers, outplacement assistance, clear and direct communication of layoff information, and support services for “survivors” of layoffs. These examples highlight the benefits of collaboration among downsizing businesses, public sector organizations, and unions in helping laid‐off employees adjust to unemployment and obtain satisfactory reemployment.
The role of mutual trust in effective downsizing strategies
Authors: Mishra Aneil K. , Mishra Karen E. 
Published: May 2007

AbstractSeveral factors that explain differences in the downsizing strategies utilized in organizations are examined in this study of 91 organizations in the automotive industry. Specifically, mutual trust within a top management team is positively associated with a strategy based on organization redesign. Mutual trust between members of an organization and its key customers and suppliers is positively associated with a strategy based on systemic change. Moreover, these two strategies are positively associated with performance outcomes in the areas of cost reduction and quality improvement.
Increased expression and altered subunit composition of proteasomes induced by continuous proteasome inhibition establish apoptosis resistance and hyperproliferation of Burkitt lymphoma cells
Authors: Fuchs Dominik , Berges Carsten , Opelz Gerhard , Daniel Volker , Naujokat Cord 
Published: May 2007

AbstractThe proteasome is the main protease for extralysosomal protein degradation in eukaryotic cells, and constitutes a sophisticated high molecular mass proteinase complex underlying a tightly coordinated expression and assembly of multiple subunits and subcomplexes. Here we show that continuous inhibition of proteasomal chymotrypsin‐like peptidase activity by the proteasome inhibitor bortezomib induces in human Namalwa Burkitt lymphoma cells increased de novo biogenesis of proteasomes accompanied by increased expression of the proteasome maturation protein POMP, increased expression of 19S‐20S‐19S proteasomes, and abrogation of expression of β1i, β2i and β5i immunosubunits and PA28 in favor of increased expression of constitutive proteolytic β1, β2 and β5 subunits and 19S regulatory complexes. These alterations of proteasome expression and subunit composition are accompanied by an increase in proteasomal caspase‐like, trypsin‐like and chymotrypsin‐like peptidase activities, not inhibitable by high doses of bortezomib. Cells harboring these proteasomal alterations display rapid proliferation and cell cycle progression, and acquire resistance to apoptosis induced by proteasome inhibitors, γ‐irradiation and staurosporine. This acquired apoptosis resistance is accompanied by de novo expression of anti‐apoptotic Hsp27 protein and the loss of ability to accumulate and stabilize pro‐apoptotic p53 protein. Thus, increased expression, altered subunit composition and increased activity of proteasomes constitute a hitherto unknown adaptive and autoregulatory feedback mechanism to allow cells to survive the lethal challenge of proteasome inhibition and to establish a hyperproliferative and apoptosis‐resistant phenotype. J. Cell. Biochem. 103: 270–283, 2008. © 2007 Wiley‐Liss, Inc.
Differential calreticulin expression affects focal contacts via the calmodulin/CaMK II pathway
Authors: Szabo Eva , Papp Sylvia , Opas Michal 
Published: May 2007

AbstractCalreticulin is an ER calcium‐storage protein, which influences gene expression and cell adhesion. In this study, we analysed the differences in adhesive properties of calreticulin under‐ and overexpressing fibroblasts in relation to the calmodulin‐ and calcium/calmodulin‐dependent kinase II (CaMK II)‐dependent signalling pathways. Cells stably underexpressing calreticulin had elevated expression of calmodulin, activated CaMK II, activated ERK and activated c‐src. Inhibition of calmodulin by W7, and CaMK II by KN‐62, caused the otherwise weekly adhesive calreticulin underexpressing cells to behave like the overexpressing cells, via induction of increased cell spreading. Increased vinculin, activated paxillin, activated focal adhesion kinase and fibronectin levels were observed upon inhibition of either the calmodulin or the CaMK II signalling pathways, which was accompanied by an increase in cell spreading and focal contact formation. Both KN‐62 and W7 treatment increased cell motility in underexpressing cells, but W7 treatment led to loss of directionality. Thus, both the calmodulin and CaMK II signalling pathways influence cellular spreading and motility, but subtle differences exist in their distal effects on motility effectors. J. Cell. Physiol. 213: 269–277, 2007. © 2007 Wiley‐Liss, Inc.
PSMD9 gene variants within NIDDM2 may rarely contribute to type 2 diabetes
Authors: Gragnoli C. , Cronsell J. 
Published: May 2007

AbstractMultiple genome‐wide scans in different populations have linked the chromosome 12q24 region, known as NIDDM2 (non‐insulin‐dependent‐diabetes, locus 2), to type 2 diabetes. Within NIDDM2 we examined the PSMD9 (proteasome modulator 9/Bridge‐1) gene that encodes a PDZ‐domain transcriptional coactivator of insulin production. Our goal was to identify a potential contribution of the PSMD9 gene to type 2 diabetes in Italians. We directly sequenced the entire gene PSMD9 in Italian type 2 diabetes patients (n = 237) and controls subjects (n = 215) and performed an association study with the identified gene variants. We found five single nucleotide polymorphisms (SNPs), A17V, IVS1+nt29, IVS3+nt460, IVS3+nt437, and E197G, which are not associated with disease in our case–control study. Furthermore, we identified two PSMD9 gene variants in type 2 diabetes patients, which produced nonconservative amino acid substitutions S143G and N166S within the PDZ domain and two other gene variants. Three out of four of these variants are absent from the control subjects screened. We propose that the three PSMD9 gene variants (S143G, N166S and G > A at IVS3+nt102), absent in control subjects, contribute rarely to late‐onset type 2 diabetes in Italians. In fact, the frequency rate of such variants in unrelated cases equals 0.016. We may not exclude that PSMD9 gene variants may contribute, either commonly or rarely, to an increased risk of type 2 diabetes in other populations. J. Cell. Physiol. 212:568–571, 2007. © 2007 Wiley‐Liss, Inc.
Exogenous hydrogen sulfide induces functional inhibition and cell death of cytotoxic lymphocytes subsets
Authors: Mirandola Prisco , Gobbi Giuliana , Sponzilli Ivonne , Pambianco Maurizia , Malinverno Chiara , Cacchioli Antonio , De Panfilis Giuseppe , Vitale Marco 
Published: May 2007

AbstractThe toxic effects of exogenous hydrogen sulfide on peripheral blood lymphocytes have been investigated in detail. Hydrogen sulfide is now considered as a gasotransmitter with specific functional roles in different cell types, like neurons and vascular smooth muscle. Here we show that exogenous hydrogen sulfide induces a caspase‐independent cell death of peripheral blood lymphocytes that depends on their intracellular glutathion levels, with a physiologically relevant subset specificity for CD8+ T cells and NK cells. Although lymphocyte activation does not modify their sensitivity to HS−, after 24 h exposure to hydrogen sulfide surviving lymphocyte subsets show a dramatically decreased proliferation in response to mitogens and a reduced IL‐2 production. Overall, our data demonstrate that HS− reduces the cellular cytotoxic response of peripheral blood lymphocytes as well as their production of IL‐2, therefore de‐activating the major players of local inflammatory responses, adding new basic knowledge to the clinically well known anti‐inflammatory effects of sulfur compounds. J. Cell. Physiol. 213:826–833. © 2007 Wiley‐Liss, Inc.