bluuebunny/crossref_metadata_2025 huggingface dataset:
Involuntary competence
Authors: Morse Stephen J.
Published: June 2003

This article addresses whether the state has the right to medicate involuntarily a defendant who is incompetent either to plead guilty or to stand trial for the purpose of restoring legal competence. It first presents the constitutional background concerning incompetence and the right of prisoners generally to refuse psychotropic medication. Then the article examines the individual and state interests that must be considered to decide specifically whether the state may involuntarily medicate a criminal defendant solely for the purpose of restoring competence. Although the individual interests are strong, the article contends that the state does have a right to medicate involuntarily defendants charged with most crimes to restore trial competence, and that adequate remedies are available to ensure that medicated defendants receive a fair trial. Copyright © 2003 John Wiley & Sons, Ltd.
Rigorous Modeling of Reactive Absorption Processes
Authors: Kenig E.Y. , Kucka L. , Górak A.
Published: June 2003

Absorption of gases in liquid solutions accompanied by chemical reactions, or reactive absorption, represents one of the most important industrial operations. The advantages of this process are enhanced solution capacity, low impurity concentrations up to the ppm range, moderate operation pressure, and selective removal of contaminants. Reactive absorption is based on a combination of various kinetically controlled phenomena, the focus being on the coupling of chemical reactions and mass transfer in multicomponent mixtures. Therefore, the process description using the equilibrium concept is often insufficient and kinetic modeling is required. This paper describes the basics of rigorous modeling of reactive absorption processes. Several case studies are used in order to validate the models. In addition, a discussion of necessary model parameters, like diffusion coefficients and reaction kinetics, is given. A reduced model with lower computation time is obtained via detailed sensitivity analysis. This model is successfully used in dynamic simulations. In this respect, a proper consideration of the film reactions appears to be crucial.
Influence of Entrance Droplet Size Distribution and Feed Concentration on Separation of Immiscible Liquids Using Hydrocyclones
Authors: Meyer M. , Bohnet M.
Published: June 2003

When separating two immiscible liquids with a hydrocyclone a change of the entrance droplet size distribution occurs within the flow field of the hydrocyclone. This change, caused by droplet breakup and/or coalescence, has a decisive influence on the separation efficiency and has to be taken into account when designing a hydrocyclone for liquid/liquid separation. With a new design model a reliable design of hydrocyclones for liquid/liquid separation is possible.
Redox Phenomena during Adsorption of Aniline on Fe‐ and Zn‐bound SDS Micelles
Authors: Talens‐Alesson F.I.
Published: June 2003

The co‐adsorption of aniline by complex‐formation with Zn‐bound and Fe‐bound micelles of anionic surfactant SDS (sodium laurylsulphate) causes redox reactions. This happens both in cases where micelles become insoluble due to Fe‐induced flocculation and in cases where micelles remain in solution. The interest in the phenomenon is that micellar flocculation is a means of pollutant removal by itself and synergistic effects between both flocculation and oxidation may exist.
Non‐Invasive Process Imaging – Principles and Applications of Industrial Process Tomography
Authors: Dyakowski T. , Jaworski A.J.
Published: June 2003

In chemical industries, process diagnostics have traditionally been achieved using discrete sensors installed in the critical plant locations and linked into a plant control system. The usefulness of such an approach is limited, as important information about the processes is lost. This paper demonstrates a different way of looking into the spatial and temporal characteristics of the industrial processes by employing techniques of industrial process tomography. The principles behind tomographic measurements are outlined and examples illustrating the capabilities of this approach are presented. These include imaging of the processes confined within process vessels such as fluidization and nylon polymerization, as well as an example of a transport‐dominated process – flow in a pneumatic conveyor. The advantages, limitations and potential future uses of process tomography are discussed.
Triggering of Toll‐like receptors modulates IFN‐γ signaling: involvement of serine 727 STAT1 phosphorylation and suppressors of cytokine signaling
Authors: Dalpke Alexander H. , Eckerle Susan , Frey Markus , Heeg Klaus
Published: June 2003

Microbial stimuli activate cells of the innate immune system by triggering Toll‐like receptors (TLR). Activation of macrophages and dendritic cells is further enhanced by secondary signals like IFN‐γ. Here we analyzed the interplay of IFN‐γ and TLR signaling in cells of the innate immune system. Using a STAT1‐dependent reporter construct we show that IFN‐γ signaling can be enhanced as well as inhibited by simultaneous stimulation with either defined TLR agonists or whole‐bacterial lysates. Short costimulation resulted in the amplification of IFN‐γ signaling and was attributable to the p38 mitogen‐activated protein kinase (MAPK)‐dependent phosphorylation of signal transducer and activator of transcription (STAT)1 on serine 727. In contrast, prolonged co‐incubation as well as pre‐incubation with TLR agonists led to an inhibition of IFN‐γ signaling. TLR triggering induced expression of suppressor of cytokine signaling (SOCS)‐1, SOCS‐3 and cytokine‐inducible SH2 domain‐containing protein (CIS). Overexpression of SOCS‐1 and, to a lesser extend, of SOCS‐3 and CIS inhibited IFN‐γ signaling as measured by activation of STAT1. Moreover, pre‐incubation with TLR‐dependent stimuli impaired IFN‐γ‐induced MHC class II regulation but enhanced CD40 and CD86 expression. Taken together, the results indicate a tight interplay between TLR and IFN‐γ signaling pathways which involve induction of SOCS proteins and serine phosphorylation of STAT1.
Cell‐surface bound pertussis toxin induces polyclonal T cell responses with high levels of interferon‐γ in the absence of interleukin‐12
Authors: Wakatsuki Ayako , Borrow Persephone , Rigley Kevin , Beverley Peter C. L.
Published: June 2003

Pertussis toxin (PTx), an exotoxin produced by Bordetella pertussis, has long been used as a mucosal adjuvant. We examined the T cell stimulatory properties of PTx in order to dissectits mechanisms of adjuvanticity. PTx or the B‐oligomer of PTx (PTxB) failed to activate purified murine CD4+ or CD8+ T cells, as measured by a lack of proliferation or expression of early T cell activation markers. However, these T cells proliferated extensively in response to the toxin in the presence of syngeneic DC, and proliferation was accompanied by a high level of IFN‐γ production in the absence of IL‐12. Interestingly, such responses were independent of signals mediated by MHC–TCR interaction. Both PTx and PTxB were found to bind stably to the surface of DC, and increased the adherence of DC to surrounding cells. These data suggest that polyclonal T cell responses mediated by the toxin are likely to be caused by the toxin bound on the surface of APC, either cross‐linking cell surface molecules on T cells, or directly stimulating T cells together with the co‐stimulatory molecules expressed on APC. B. pertussis may use this toxin as a mechanism to evade a specific immune response.
Characterization of the B cell response of patients with anti‐liver cytosol autoantibodies in type 2 autoimmune hepatitis
Authors: Lapierre Pascal , Johanet Catherine , Alvarez Fernando
Published: June 2003

Anti‐liver cytosol type 1 (LC1) autoantibody is detected in 30% of sera from patients with type 2 autoimmune hepatitis (AIH), and is the only circulating autoantibody in 10% of cases. Human formiminotransferase cyclodeaminase (FTCD) has been shown to be the specific liver antigen recognized by anti‐LC1 autoantibodies. The aim of this study was to identify the dominant epitope on human FTCD and to analyze antigenic‐site sequences for clues on the development of AIH. Recombinant proteins and peptides covering the entire cDNA of human FTCD were tested against anti‐LC1 autoantibodies. Conformational epitopes were found throughout the protein but linear epitopes were found exclusively in the C‐terminal 146 amino acids. Two groups of sera with different reactivities were found: 69%of the sera recognized two specific linear epitopes at positions 428–434 (NTPEEKD) and 440–447 (LQEGLRRA) of human FTCD; others reacted only with a discontinuous epitope between the amino acids at position 395 and 528. FTCD autoantibody production is thus a polyclonal‐antigen‐driven B cell response. Autoantibodies against conformational or discontinuous epitopes were found in all patients and two‐thirds also recognized linear epitopes on human FTCD.
Intrathymic NKT cell development is blocked by the presence of α‐galactosylceramide
Authors: Pellicci Daniel G. , Uldrich Adam P. , Kyparissoudis Konstantinos , Crowe Nadine Y. , Brooks Andrew G. , Hammond Kirsten J. L. , Sidobre Stephané , Kronenberg Mitchell , Smyth Mark J. , Godfrey Dale I.
Published: June 2003

NKT cell development takes place in the thymus, beginning when these cells branch away from CD4+CD8+ mainstream thymocytes upon expression of the Vα14Jα18 T cell receptor (TCR) and recognition of the CD1d molecule. Although NKT cells express an invariant TCR α chain, the diverse TCR β expression leaves open the possibility that the development of these cells is shaped by glycolipid antigen recognition in the context of CD1d. Here, we show that the presence of an agonist glycolipid ligand, α‐galactosylceramide, while NKT cells are developing in vitro or in vivo, specifically ablates their development. In contrast, the delayed introduction of this compound in vitro or in vivo, after NKT cells have developed, does not deplete these cells. These data indicate that NKT cells pass through a developmental window where they are susceptible to TCR‐mediated negative selection, and suggest that NKT cells with a potentially high level of self reactivity can be removed from the NKT cell repertoire before they exit the thymus.
Synthesis of tripod Ligands Containing Mixed Donor Sets with Phosphane and Pyrazole Donors − Bidentate Chelate Binding Modes and Dynamic Behaviour of tripod Ligands in d8‐Metal Complexes (NiII, PdII, PtII)
Authors: Faissner Ralf , Huttner Gottfried , Kaifer Elisabeth , Kircher Peter , Rutsch Peter , Zsolnai Laszlo
Published: June 2003

The synthesis of a series of tripod ligands MeOCH2C(CH2X)(CH2Y)(CH2Z) (X = PR2; Y, Z = PR′2 or pz; pz = 1‐pyrazolyl) based on the 3,3‐difunctionalized oxetane Oa[CH2]2Ca(CH2OMs)(CH2Br)(Oa−Ca) as the starting material is described. With their mixed donor sets these ligands coordinate to d8‐metal ions in a bidentate binding mode. One of the three donors remains uncoordinated in each case. Coordination of phosphane donors is generally preferred over coordination of pyrazole donors. With bulky phosphanes such as −CH2PMes2, however, pyrazole may compete with PR2, depending on the kind of the d8 fragment. Dynamic exchange between coordinated and noncoordinated pyrazole donors is observed. Tetracoordinate complexes of the general type L2MR2 are formed (L2 symbolizes the tripod ligand in its bidentate chelate binding mode with two donors functions coordinating and the third one serving as a dangling arm; M = NiII, PdII, PtII). With nickel(II) as the d8 species, tetrahedral or square‐planar coordination geometries ensue, depending on the kind of donor functions and on the kind of co‐ligands R. With palladium(II) and platinum(II) as the d8 centres, square‐planar coordination is observed throughout. The size of the chelate cycles varies from six to eight depending on the number of pyrazole entities within the cycle. The conformations and the conformational flexibility characterizing the chelate cycles have been analysed by X‐ray analyses and by variable‐temperature NMR. The classes of conformations observed may be formally reduced to chair, half‐chair and twist‐boat conformations. Dynamic exchange between these conformations is observed. In one case, the same compound forms two different types of crystals that differ by the conformation adopted by their chelate cycles. All compounds have been fully characterized by standard analytical techniques including X‐ray structure analysis of 14 chelate compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Nickel(II) Compounds Derived from tripod Ligands: Efficient Catalysts for the Stereoselective Heterodimerization of Styrene and Propene
Authors: Faissner Ralf , Huttner Gottfried
Published: June 2003

The tripod ligands RCH2C(CH2X)(CH2Y)(CH2Z) form tetracoordinate compounds with NiHal2. If two of the donor functions X, Y, Z are phosphanes, square‐planar coordination is observed. In contrast, donor sets X,Y,Z = P,N,N or N,N,N form tetrahedral compounds, by P,N or N,N coordination, that are active in the catalysis of olefin oligomerization with MAO as a co‐catalyst. These catalyst systems are also active in the stereoselective heterodimerization of olefins. The co‐dimerization of styrene and propene by these systems leads to 4‐phenyl‐2‐pentene almost exclusively, with regioselectivities up to 98% and (E)/(Z) ratios of up to 95:5, surpassing other reported catalysts for this process. The products of these catalytic transformations have been fully characterized by GC/MS techniques as well by isolation, NMR and MS characterization of the pure compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis, Crystal Structures and Third‐Order Nonlinear Optical Properties of Two Novel Ferrocenyl Schiff‐Base Complexes [Ag(L)2](NO3)⋅(MeOH)⋅(EtOH) and [HgI2(L)] {L = 1,2‐Bis[(ferrocen‐l‐ylmethylene)amino]ethane}
Authors: Hou Hongwei , Li Gang , Song Yinglin , Fan Yaoting , Zhu Yu , Zhu Lu
Published: June 2003

Two novel ferrocenyl complexes [Ag(L)2](NO3)·(MeOH)· (EtOH) (1) and [HgI2(L)] (2) {L = 1,2‐bis[(ferrocen‐l‐ylmethylene)amino]ethane} have been prepared and structurally characterized by means of X‐ray single crystal diffraction. The central ion, silver(I) or mercury(II), has a distorted tetrahedral environment, the silver(I) ion coordinates with two L, and the mercury(II) ion binds one L and two iodine atoms. Their third‐order nonlinear optical (NLO) properties were determined by Z‐scan techniques in DMF solution. The results indicate that the two complexes exhibit very strong NLO absorption and strong self‐focusing effects. The third‐order NLO absorptive coefficients α2 are 1.34 × 10−8 m W−1 for 1 and 3.1 × 10−9 m W−1 for 2. The refractive indexes n2 for the two complexes are 1.15 × 10−18 and 8.02 × 10−19 m2 W−1, respectively. The hyperpolarizability γ values are calculated to be 2.68 × 10−30 esu for 1 and 1.44 × 10−30 esu for 2. The γ values are several orders of magnitude larger than those of the reported aryl and vinyl derivatives of ferrocene. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Reduction of [(C5Me5)2Mo2O5] and [(C5Me5)2Mo2O4] in Methanol/Water/Trifluoroacetate Solutions Investigated by Combined On‐Line Electrochemistry/Electrospray‐Ionization Mass Spectrometry
Authors: Gun Jenny , Modestov Alexandre , Lev Ovadia , Poli Rinaldo
Published: June 2003

Complexes [Cp*2Mo2O5] (Cp* = η5‐C5Me5) and [Cp*2Mo2O4] were investigated by combined on‐line electrochemical (EC) reduction and electrospray‐ionization mass spectrometry (ESI‐MS) techniques in a trifluoroacetic acid buffered water/methanol solution. The reduction products at the larger negative potentials are identical for both compounds. The studies reveal the existence of a wide range of previously unknown di‐ and trinuclear MoV, MoIV, MoIII, and mixed‐valence complexes that were identified on the basis of their masses and characteristic isotope patterns. The structures of the initial compounds and the product of electroreduction with m/z = 713−729 were supported by in situ MSn experiments that allowed the elucidation of the fragmentation pathway for the collision‐induced dissociation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Ternary Mononuclear and Ferromagnetically Coupled Dinuclear Copper(II) Complexes of 1,10‐Phenanthroline and N‐Salicylidene‐2‐methoxyaniline that Show Supramolecular Self‐Organization
Authors: Reddy Pattubala A. N. , Nethaji Munirathinam , Chakravarty Akhil R.
Published: June 2003

The ternary copper(II) complex [Cu(phen)(L)](ClO4) (1) and dinuclear copper(II) complex [Cu2(phen)3(L)(O2CMe)](ClO4)2 (2) have been prepared and characterized structurally by X‐ray crystallography (HL: N‐salicylidene‐2‐methoxyaniline; phen: 1,10‐phenanthroline). The crystal structure of 1 displays a square‐pyramidal [4+1] coordination geometry in which the basal plane has three nitrogen donor atoms and the phenolate oxygen atom of the Schiff base. The methoxy oxygen atom exhibits axial coordination in the CuN3O2 chromophore. Complex 2 has a dinuclear copper(II) core in which the Cu(phen)22+ and Cu(phen)(L)+ units are linked by an acetate ion showing equatorial/axial modes of bonding. In the bis(phen) unit, the basal plane has three nitrogen atoms and the acetate oxygen atom with one phen nitrogen atom occupying the axial site. In the mono(phen) unit, the basal plane has three nitrogen atoms and one phenolate oxygen atom. The acetate oxygen atom occupies the axial site. The equatorial/axial bridging mode of the acetate ion makes the dicopper(II) unit weakly ferromagnetic (2J = +22 cm−1) and the complex in CH2Cl2 glass at 77 K shows an axial EPR spectrum [g|| = 2.23 (A|| = 150 × 10−4 cm−1); g⊥ = 2.03] corresponding to a ΔMs = ±1 transition and a half‐field signal due to a ΔMs = ±2 transition. Complex 1 displays an axial EPR spectrum with g|| > g⊥ indicating a {d−}1 ground state. The complexes show a d−d band near 650 nm and a charge‐transfer band at ca. 415 nm in methanol. The complexes are redox‐active and exhibit a CuII/CuI couple near 0.0 V versus SCE in DMF and CH2Cl2/0.1 M TBAP. Complex 1 is catalytically active in the oxidation of ascorbic acid by dioxygen in aqueous methanol. Complex 2 also shows similar catalytic activity, but the core is susceptible to cleavage under the reaction conditions. The complexes show π−π stacking interactions. Complex 1 forms a one‐dimensional chain through intermolecular π−π stacking interactions involving phen and the phenolate ring of the Schiff base. Complex 2 displays intramolecular and intermolecular π−π stacking interactions involving phen ligands leading to the formation of a supramspectrum with g|| > g⊥ indicating a {d−}1 ground state. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Photophysical and Energy‐Transfer Properties of (Salen)zinc Complexes and Supramolecular Assemblies
Authors: Splan Kathryn E. , Massari Aaron M. , Morris Gregory A. , Sun Shih‐Sheng , Reina Eduardo , Nguyen SonBinh T. , Hupp Joseph T.
Published: June 2003

The absorption, emission, and energy‐transfer properties of monomeric and supramolecular (salen)Zn complexes (square and rectangular assemblies) are reported. The monomeric complexes fluoresce in solution, displaying photophysical behavior similar to typical (porphyrin)zinc complexes. Rhenium coordination chemistry is used to assemble molecular rectangles and squares that largely retain the photophysical properties of the parent compounds. Host‐guest assemblies obtained by binding a fifth (salen)Zn complex to a tetrakis(salen) square are capable of efficient salen‐to‐salen electronic energy transfer. Energy transfer flow through these systems can be manipulated by modification of the salen building‐block structure. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis, Crystal Structure, and Electrical Properties of Novel Radical Cation Salts of Iodine‐Substituted TTF‐Derived Donors with the Nitroprusside Anion Exhibiting Strong ‐I···NC‐ Interactions
Authors: Ueda Kazumasa , Sugimoto Toyonari , Faulmann Christophe , Cassoux Patrick
Published: June 2003

Radical‐cation salts of iodine‐substituted TTF derivatives [diiodoethylenedithiotetrathiafulvalene (1) diiodoethylenedithiodiselenadithiafulvalene (2), or iodoethylenedithiotetrathiafulvalene (3)] with the [Fe(CN)5NO]2− nitroprusside anion, namely, 14·[Fe(CN)5NO], 24·[Fe(CN)5NO] and 33·[Fe(CN)5NO], were synthesized by electrocrystallization from solutions of the appropriate TTF derivative in CH2Cl2 with bis(tetraphenylphosphonium)nitroprusside [(PPh4)2{Fe(CN)5NO}] as electrolyte. An X‐ray structure analysis indicates that the crystal structures of 14·[Fe(CN)5NO] and 24·[Fe(CN)5NO] are very similar. In both cases, molecules 1 and 2 are stacked along the c direction, with their long molecular axis parallel to each other. By contrast, in 33·[Fe(CN)5NO], molecules 3 are stacked in triad units in which two of the molecules are arranged in a face‐to‐face fashion and the remaining molecule is arranged in a head‐to‐tail fashion with respect to its neighboring molecules. In all cases, several effective iodine‐nitrogen contacts between donor molecules and [Fe(CN)5NO]2− anions are observed. The room temperature electrical conductivities of 14·[Fe(CN)5NO], 24·[Fe(CN)5NO] and 33·[Fe(CN)5NO] are <10−6, 2.2 × 10−2 and 5 S cm−1, respectively. The temperature dependence of the electrical conductivity of 33·[Fe(CN)5NO] reveals semiconducting behavior with a small activation energy of 30 meV. The temperature dependence of the electrical conductivity of 24·[Fe(CN)5NO] also reveals a semiconducting behavior, but with two regimes: above 200 K the activation energy is 60 meV and becomes much smaller — 0.2 meV — below this temperature. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Solvothermal Synthesis and Structure of Anhydrous Manganese(II) Formate, and Its Topotactic Dehydration from Manganese(II) Formate Dihydrate
Authors: Viertelhaus Martin , Henke Henning , Anson Christopher E. , Powell Annie K.
Published: June 2003

Recrystallization of manganese(II) formate dihydrate from formic acid under solvothermal conditions results in single crystals of anhydrous manganese(II) formate Mn(O2CH)2, and the structure of this phase has been determined by X‐ray diffraction. The same product can be obtained by solid‐state dehydration of single crystals of manganese formate dihydrate, giving crystals that, although of poor quality, still allow for a single crystal structure determination. The structural relationship between the hydrated and anhydrous phases and the nature of the transformation have been determined. Given the nature of the rearrangement involved in the solid‐state reaction, it is remarkable that a crystalline product is obtained. Magnetic measurements of the anhydrous manganese(II) formate show it to be a three‐dimensional antiferromagnet. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Polymeric, Molecular, and Cation/Anion Arrangements in Chloro‐, Bromo‐, and Iododiruthenium(II,III) Carboxylate Compounds
Authors: Barral M. Carmen , González‐Prieto Rodrigo , Jiménez‐Aparicio Reyes , Priego J. Luis , Torres M. Rosario , Urbanos Francisco A.
Published: June 2003

The synthesis and characterization of the anhydrous compounds [Ru2X(μ‐O2CR)4] [R = CH2CH2OPh, X = Cl (1a), Br (2a), I (3a); R = CMePh2, X = Br (5a), I (6a)] and of the solvated complexes [Ru2X(μ‐O2CR)4(H2O)] [R = CH2CH2OPh, X = Cl (1b), I (3b); R = CMePh2, X = Cl (4b), Br (5b), I (6b)] are described. Thermogravimetric analyses have been used to confirm the anhydrous or solvated natures of the complexes. The crystal structures of 1b·2MeOH, 3b·0.5H2O, and 4b have been investigated by X‐ray diffraction and none of them shows the usual polymeric arrangement reported for tetracarboxylatodiruthenium(II,III) compounds. The structure of 3b·0.5H2O consists of cationic and anionic units, [Ru2(μ‐O2CCH2CH2OPh)4(H2O)2][Ru2I2(μ‐O2CCH2CH2OPh)4], and represents the first reported crystal structure of a tetracarboxylato(iodo)diruthenium(II,III) derivative. The structures 1b·2MeOH and 4b each show the presence of discrete dinuclear molecules. The crystal structure of [Ru2Cl(μ‐O2CCMePh2)4(H2O)] demonstrates that diruthenium compounds with the same halide and carboxylate ligands may adopt polymeric or discrete molecular dispositions. Magnetic susceptibility measurements of the complexes in the 2−300 K range have been carried out. Complex 2a shows a strong antiferromagnetic coupling, consistent with the existence of linear chains in the solid state. The complexes [Ru2X(μ‐O2CR)4(H2O)] show weak through‐space antiferromagnetic coupling, in accordance with non‐polymeric structures. The magnetic behaviour of 1a, 3a, 5a, and 6a suggests a mixture of arrangements. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis of Oxalato‐Bridged (Oxo)vanadium(IV) Dimers Using L‐Ascorbic Acid as Oxalate Precursor: Structure and Magnetism of Two Systems
Authors: Baruah Bharat , Golub Vladimir O. , O’Connor Charles J. , Chakravorty Animesh
Published: June 2003

The reaction of an aqueous solution of NH4VO3 with L‐ascorbic acid and Et4NBr has afforded [Et4N]2[(VO)2(C2O4)3‐(H2O)2]·4H2O (3). A similar reaction, in which malonic acid is also added, has furnished [Et4N]2[(VO)2(C2O4)(C3H2O4)2(H2O)2]·2H2O (4). In these syntheses the oxalate ion is derived from L‐ascorbic acid. In both the complexes the dinuclear anion is centrosymmetric. In 3 the metal atoms are displaced from the plane of the bridging oxalate anion by 0.05 Å, the corresponding displacement in 4 being 0.17 Å. The terminal oxalato chelate ring in 3 is roughly planar but the malonato chelate ring in 4 has a distorted boat conformation. The V−O distances in 4 are systematically shorter than the corresponding distances in 3 by 0.02−0.06 Å. The V···V distance within the dimer is 5.616(2) Å in 3 and 5.529(2) Å in 4. The two uncoordinated water molecules in the asymmetric unit of 3 constitute a hydrogen‐bonded dimer and the lattice consists of a supramolecular anionic assembly held by five different types of O···O hydrogen bonds. The anionic assembly in 4 involves three types of O···O hydrogen bonds. The Et4N+ cations reside between the anionic layers. The magnetic susceptibility data of both 3 and 4 fit excellently with the Heisenberg dimer model in the temperature interval 2−300 K. The species are antiferromagnetic and the J values are −6.50 cm−1 for 3 and −6.25 cm−1 for 4. The two opposing factors — V−O(bridge) bond length and the displacement of the metal atom from the oxalate plane — appear to have more or less balanced each other resulting in virtually equal J values for the two complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Cover Picture: Syntheses of Dimetallamacrocycles by Intramolecular Oxidative Couplings of Dinuclear Bis(1,3‐butadiynyl) Complexes: A New Approach to Steric Shielding in (sp‐Carbon chain)dirhenium Complexes [(η5‐C5Me5)Re(NO)(PR3)(C≡CC≡CC≡CC≡C)(R3P)(ON)Re(η5‐C5Me5)] (Eur. J. Inorg. Chem. 12/2003)
Authors: Horn Clemens R. , Gladysz John A.
Published: June 2003

The cover picture shows the first example of an isolated organometallic compound containing two terminal alkynes undergoing an intramolecular oxidative coupling. Twenty‐two‐ and twenty‐six‐membered rings or “metallamacrocycles” are obtained in 18−41 % yields. The intramolecular oxidative coupling of organic compounds containing two terminal alkynes has played a critical role in the development of macrocycle chemistry, particularly with annulenes and dehydroannulenes, and macrocyclizations are playing an increasingly important role in organometallic chemistry, particularly as attention turns to architecturally novel types of target molecules that may have applications in materials chemistry or nanotechnology. Details are discussed in the article by J. A. Gladysz et al. on p. 2211 ff.
The Use of Ultrasound for the Degradation of Pollutants in Water: Aquasonolysis – A Review
Authors: Lifka J. , Ondruschka B. , Hofmann J.
Published: June 2003

The degradation of organic compounds in water is the subject of a number of fundamental and applied investigations. Aquasonolysis of organic compounds is an advanced technology for the purification of contaminated water. The process is based on the phenomenon of acoustic cavitation. Dominant reactions of volatile compounds are: cavitative high‐temperature gas‐phase reactions and thermal‐oxidative decay in bubbles. Nonvolatile compounds are mainly decomposed by OH radicals in the aqueous solution (sonolytical cleavage of water). This article reviews mechanisms and kinetics of pollutant decomposition in water and discusses the influence of different experimental parameters. An overview of the application spectrum of aquasonolysis is provided, analyzing results gathered in experiments completed in our group as well as results reported in the literature.
Degradation of Halogenated Hydrocarbons by the Combined Application of Membrane Filtration with a Bioreactor
Authors: Schierenbeck A. , Haase C. , Räbiger N.
Published: June 2003

The selective biological elimination of hazardous substances from wastewater is of vital importance for production‐integrated pollution control. It provides an opportunity to degrade otherwise persistent substances from wastewater mixtures. State‐of‐the‐art industrial wastewater treatment plants cannot perform this task although the potential for an enzymatic degradation of most of these substances exists. This is due to the hydrodynamically determined mixing characteristics of the treatment plants. The aim of developing new technologies should be the adjustment of substrate‐specific residence times at immobilized biomass.
Analysis of multilocus models of association
Authors: Devlin B. , Roeder Kathryn , Wasserman Larry
Published: June 2003

It is increasingly recognized that multiple genetic variants, within the same or different genes, combine to affect liability for many common diseases. Indeed, the variants may interact among themselves and with environmental factors. Thus realistic genetic/statistical models can include an extremely large number of parameters, and it is by no means obvious how to find the variants contributing to liability. For models of multiple candidate genes and their interactions, we prove that statistical inference can be based on controlling the false discovery rate (FDR), which is defined as the expected number of false rejections divided by the number of rejections. Controlling the FDR automatically controls the overall error rate in the special case that all the null hypotheses are true. So do more standard methods such as Bonferroni correction. However, when some null hypotheses are false, the goals of Bonferroni and FDR differ, and FDR will have better power. Model selection procedures, such as forward stepwise regression, are often used to choose important predictors for complex models. By analysis of simulations of such models, we compare a computationally efficient form of forward stepwise regression against the FDR methods. We show that model selection includes numerous genetic variants having no impact on the trait, whereas FDR maintains a false‐positive rate very close to the nominal rate. With good control over false positives and better power than Bonferroni, the FDR‐based methods we introduce present a viable means of evaluating complex, multivariate genetic models. Naturally, as for any method seeking to explore complex genetic models, the power of the methods is limited by sample size and model complexity.Genet Epidemiol25:36–47, 2003. © 2003 Wiley‐Liss, Inc.
Evolutionary‐based association analysis using haplotype data
Authors: Seltman Howard , Roeder Kathryn , Devlin B.
Published: June 2003

Association studies, both family‐based and population‐based, can be powerful means of detecting disease‐liability alleles. To increase the information of the test, various researchers have proposed targeting haplotypes. The larger number of haplotypes, however, relative to alleles at individual loci, could decrease power because of the additional degrees of freedom required for the test. An optimal strategy would focus the test on particular haplotypes or groups of haplotypes, much as is done with cladistic‐based association analysis. First suggested by Templeton et al. ([1987] Genetics 117:343–351), such analyses use the evolutionary relationships among haplotypes to produce a limited set of hypothesis tests and to increase the interpretability of these tests. To more fully utilize the information contained in the evolutionary relationships among haplotypes and in the sample, we propose generalized linear models (GLM) for the analysis of data from family‐based and population‐based studies. These models fully account for haplotype phase ambiguity and allow for covariates. The models are encoded into a software package (the Evolutionary‐Based Haplotype Analysis Package, EHAP), which also provides for various kinds of exploratory data analysis. The exploratory analyses, such as error checking, estimation of haplotype frequencies, and tools for building cladograms, should facilitate the implementation of cladistic‐based association analysis with haplotypes. Genet Epidemiol 25:48–58, 2003. © 2003 Wiley‐Liss, Inc.
Remembering the contributions of Kenneth I. Howard: An introduction
Authors: Beutler Larry E.
Published: June 2003

This special issue of the Journal of Clinical Psychology recognizes the contributions of Kenneth I. Howard, one of the most influential and productive contemporary scholars in the domain of psychotherapy process and outcome. The articles address some of the major contributions by Dr. Howard and extend their implications to contemporary clinical practice and research. © 2003 Wiley Periodicals, Inc. J Clin Psychol.
What random assignment does and does not do
Authors: Krause Merton S. , Howard Kenneth I.
Published: June 2003

Random assignment of patients to comparison groups stochastically tends, with increasing sample size or number of experiment replications, to minimize the confounding of treatment outcome differences by the effects of differences among these groups in unknown/unmeasured patient characteristics. To what degree such confounding is actually avoided we cannot know unless we have validly measured these patient variables, but completely avoiding it is quite unlikely. Even if this confounding were completely avoided, confounding by unmeasured Patient Variable × Treatment Variable interactions remains a possibility. And the causal power of the confounding variables is no less important for internal validity than the degree of confounding. © 2003 Wiley Periodicals, Inc. J Clin Psychol.
A cautionary note on deviation scores for the WISC‐III and WAIS‐III
Authors: Charter Richard A.
Published: June 2003

This article highlights some dangers inherent in interpreting individual examinee strengths and weaknesses in WAIS‐III and WISC‐III profiles. In both manuals, there are tables providing point estimates for determining if a significant difference exists when comparing one subtest to the average of several subtests. However, these point estimates may lead to interpretation errors. A confidence interval approach that provides a solution to the interpretation problem is described and illustrated. These intervals show that differences between a single subtest score and the average subtest score that just reach statistical significance carry the potential of having no clinical significance. © 2003 Wiley Periodicals, Inc. J Clin Psychol.
The Pain Distress Inventory: Development and initial psychometric properties
Authors: Osman Augustine , Barrios Francisco X. , Gutierrez Peter M. , Kopper Beverly A. , Butler Adam , Bagge Courtney L.
Published: June 2003

A new 26‐item self‐report measure, the Pain Distress Inventory (PDI), was designed to assess affective distress symptoms related to physical pain. Phases 1 to 3 were designed to construct the PDI using contemporary test development strategies. Studies 1 and 2 were conducted to define and confirm the four‐factor oblique structure of the PDI: PDI‐Depression, PDI‐Anger, PDI‐Pain Sensitivity, and PDI‐Somatic Anxiety. The internal consistency reliability estimates were high for both the PDI total and scale scores. Study 3 examined relationships of the PDI with demographic variables and pain‐ and psychological‐related responses. Scores on the PDI were useful in predicting scores on a pain‐interference index and a pain‐symptom index. Study 4 was designed to replicate previous findings of reliability and validity. The PDI total and scale scores were useful in differentiating between the responses of the clinic and nonclinic study participants. Limitations and potential uses of the PDI are discussed. © 2003 Wiley Periodicals, Inc. J Clin Psychol.
The perceived effects of holiday‐taking upon the health and wellbeing of patients treated for cancer
Authors: Hunter‐Jones Philippa
Published: June 2003

The role that holidays play within health and wellbeing has been addressed infrequently within academic research. Much of the work that does exist has tended to focus upon illnesses or health complaints arising as a consequence of travel. Any beneficial health effects of travel largely have been neglected. This paper reports the empirical findings of a qualitative study conducted to determine the perceived effects of holiday‐taking upon the health and wellbeing of a group of cancer patients, a population ignored by the tourism community. Four perceived effects are identified relating to personal health, social effectiveness, personal identity and regaining independence, and the implications of these findings discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Unionisation in the Dublin hotel industry
Authors: Piso Annemarie
Published: June 2003

The Dublin hotel industry experiences significantly higher levels of union density than is the case amongst hotel workers in the UK. This paper examines the context in which these different experiences of union density take place. It provides an examination of the historical roots of union organisation within Dublin hotels and explores the factors that have contributed to effective organisation within the industry today. It concludes by arguing that although the structural characteristics of employment in the UK can act as a barrier to union organisation, these can, in certain historical periods, be overcome where there is a shifting balance of power between workers and employers affecting both the hotel industry and society as a whole. Copyright
© 2003 John Wiley & Sons, Ltd.
Mortars for encapsulating sacrificial zinc anodes in reinforced concrete
Authors: Jordan Lee C. , Page Christopher L.
Published: June 2003

Expansion measurements, chemical analysis and petrography have been undertaken to assess a possible side‐effect of using strongly alkaline additives (lithium hydroxide or sodium hydroxide) in encapsulating mortars used to promote the activity of sacrificial zinc anodes employed for galvanic cathodic protection of steel in concrete. Very high concentrations of lithium hydroxide in the encapsulating mortars were found to cause no deleterious expansion associated with alkali‐silica reaction (ASR) in surrounding “model” concrete specimens even when the latter contained aggregate of known susceptibility to ASR and a near‐threshold level of intrinsic alkalinity. Encapsulating mortars formulated with an equivalent molarity of sodium hydroxide, however, were found to induce significant expansion due to ASR in similar specimens.
Gerissener Stahlbeton: Wie korrosionsgefährdet ist die Bewehrung?
Authors: Gehlen C. , Sodeikat C.
Published: June 2003

Zum Bemessungsprinzip von Stahlbetonbauteilen gehört es in der Regel, dass der Beton im Zugbereich aufreißt und die Zugkräfte von der Stahlbewehrung aufgenommen werden. Durch konstruktive Maßnahmen können die entstehenden Risse in ihrer Breite beschränkt werden. Bereits Ende der fünfziger Jahre wurden erste Untersuchungen durchgeführt, um den Einfluss von Rissen und Rissbreite auf das Korrosionsrisiko zu erfassen. Korrosionsfördernde Stoffe wie CO2 und Chloride können in Rissbereichen wesentlich rascher zum Bewehrungsstahl vordringen als in ungerissenen Bereichen; die Zeitphase der Depassivierung der Bewehrung ist in Rissbereichen deshalb wesentlich schneller abgeschlossen. Bevor Schießl seine grundlegenden Versuche und Literaturauswertungen zum Einfluss der Rissbreite auf die Korrosionsgeschwindigkeit der Bewehrung in Rissbereichen veröffentlichte, ging man davon aus, dass die Korrosionsgeschwindigkeit mit der Rissbreite zunimmt. Bis zur Fassung der DIN 1045 von 1988 wurden deshalb die einzuhaltenden Rissbreiten in Abhängigkeit von den Umwelteinwirkungen gestaffelt vorgegeben. Die Fassung der DIN 1045 von 1988 enthielt diese Staffelung erstmals nicht mehr, zur Sicherung der Dauerhaftigkeit von Stahlbetonbauwerken wurde ein Rechenwert von 0,25 mm festgelegt. In der Fassung der DIN 1045 von 2001 ist der Rechenwert der Rissbreite von 0,25 mm auf 0,30 mm heraufgesetzt worden. In letzter Konsequenz sind nunmehr die Erkenntnisse, welche Schießl in Heft 370 des Deutschen Ausschusses für Stahlbeton veröffentlicht hat, umgesetzt worden. Entscheidend für die Korrosionsgeschwindigkeit der Bewehrung in Rissbereichen ist die Dichte und die Dicke der Betondeckung und nicht die Rissbreite, wobei horizontale Bauteile mit Chloridbeaufschlagung generell durch zusätzliche Maßnahmen geschützt werden sollten.
Kritischer korrosionsauslösender Chloridgehalt – Untersuchungen an Mörtelelektroden in chloridhaltigen alkalischen Lösungen
Authors: Breit W.
Published: June 2003

Obwohl das Eindringen von Chloridionen in den Beton durch zahlreiche Schutzmechanismen behindert wird, der Beton also ein komplexes Mehrbarrierenschutzsystem darstellt, gelingt es den Chloridionen dennoch, wie die zahlreichen chloridinduzierten Korrosionsschäden aus der Baupraxis eindeutig belegen, die schützende Passivoxidschicht des Stahles zu durchbrechen. In einem ersten Teil wurde über die Ergebnisse berichtet, die am reduzierten Korrosionssystem Stahl/Betonporenlösung durchgeführt wurden [1]. Im vorliegenden Artikel werden die Untersuchungsergebnisse zum kritischen korrosionsauslösenden Chloridgehalt, die in elektrochemischen Untersuchungen an Mörtelelektroden in chloridhaltigen alkalischen Lösungen erzielt wurden, vorgestellt. Abschließend werden die gewonnenen Erkenntnisse im Hinblick auf die sich ergebende Bedeutung für die Baupraxis, im Speziellen für die Planung von Neubaumaßnahmen und für die Beurteilung von bestehenden Bauwerken, erläutert.
Termination in Dilute‐Solution Free‐Radical Polymerization: A Composite Model
Authors: Smith Gregory B. , Russell Gregory T. , Heuts Johan P.A.
Published: June 2003

Literature data are summarized for the chain‐length‐dependence of the termination rate coefficient in dilute solution free‐radical polymerizations. In essence such experiments have yielded two parameter values: the rate coefficient for termination between monomeric free radicals, k, and a power‐law exponent e quantifying how kt values decrease with increasing chain length. All indications are that the value e ≈ 0.16 in good solvent is accurate, however the values of k which have been deduced are considerably lower than well‐established values for small molecule radicals. This seeming impasse is resolved by putting forward a ‘composite’ model of termination: it is proposed that the value e ≈ 0.16 holds only for long chains, with e being higher for small chains – the value 0.5 is used in this paper, although it is not held to dogmatically. It is then investigated whether this model is consistent with experimental data. This is a non‐trivial task, because although the experiments themselves and the ways in which they are analyzed are elegant and not too complicated, the underlying theory is sophisticated, as is outlined. Simulations of steady‐state polymerization experiments are first of all carried out, and it is shown that the composite model of termination both recovers the e values which have been found and beautifully explains why these experiments considerably underestimate the true value of k. Simulations of pulsed‐laser polymerizations find the same, although not quite so strikingly. It is therefore concluded that our new termination model, which retains the virtue of simplicity and in which all parameter values are physically reasonable, is consistent with experimental data. Taking a wider view, it seems likely that the situation of the exponent e varying with chain length will not just be the case in dilute solution, but will be the norm for all conditions, which would give our model and our work a general relevance.

Normalized chain length distributions from PLP simulations.

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Normalized chain length distributions from PLP simulations.
Effect of the Intramolecular Chain Transfer to Polymer on PLP/SEC Experiments of Alkyl Acrylates
Authors: Arzamendi Gurutze , Plessis Christophe , Leiza José R. , Asua José M.
Published: June 2003

Pulsed‐laser polymerization (PLP) has been adopted by IUPAC as the method of choice for the determination of propagation rate constants (kp). However, the method has failed in the polymerization of alkyl acrylates at temperatures above 30 °C. In this work, the PLP experiments were analyzed by simulation using a Monte Carlo algorithm. It was found that the experimental difficulties encountered to accurately determine kp at temperatures above 30 °C were caused by extensive intramolecular chain transfer. This mechanism is not operative at lower temperatures because of its high activation energy.

Pulsed‐laser polymerization of BA in bulk at temperatures between −41 and +40 °C: Simulated MWD trace.

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Pulsed‐laser polymerization of BA in bulk at temperatures between −41 and +40 °C: Simulated MWD trace.
Self‐Consistent Integral Equation Theory for Semiflexible Polyelectrolytes in Poor Solvent
Authors: Zherenkova Lubov , Khalatur Pavel , Yoshikawa Kenichi
Published: June 2003

Self‐consistent hybrid MC/PRISM method is presented for calculating properties of polyelectrolytes in semidilute and more concentrated regimes in a poor solvent. The static structure and conformational behavior of salt‐free polyelectrolyte solutions composed of semiflexible polyions and monovalent counterions are studied using the approach which combines the traditional Monte‐Carlo (MC) simulation with the numerical solution of the polymer integral PRISM equation. The MC technique is applied to generate the configurations of a single chain molecule and obtain the averaged intrapolymer correlation function. The PRISM equation is then numerically solved for a given monomer density to obtain the various correlation functions and the medium‐induced intrapolymer potential. This is used in a single chain MC simulation, where the polymer sites interact via the bare Coulomb potential together with the short range attractive potential and a self‐consistently determined medium‐induced potential. The monomer‐monomer pair correlation functions and static structure factors are calculated for a large variety of parameters. Conformational properties such as the radius of gyration and visual images are obtained as a function of attractive short‐range interaction, monomer density, Bjerrum length, and chain stiffness. The MC/PRISM study predicts that there is a range of hydrophobicity and monomer density for which polyion chains can form the toroidal structure in a poor solvent. Nonmonotonic dependence of the chain size on monomer density is predicted over the entire range of parameters. Polyion structure factor peak position as a function of density is described. Two concentration regimes in which the polyion structure factors exhibit physically different peaks were found. Over the entire concentration regime considered polyelectrolyte chains undergo strong compression with Rg ∝ l.

Conformation of a polyion chain for lB = 2, ε = 0.18 at ρ* = 0.2 and α = 10°.

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Conformation of a polyion chain for lB = 2, ε = 0.18 at ρ* = 0.2 and α = 10°.