bluuebunny/crossref_metadata_2025 huggingface dataset:
The initial development of receptivity to working abroad: Self‐initiated international work opportunities in young graduate employees
Authors: Tharenou Phyllis
Published: December 2003

This study sought to understand how receptivity to working abroad initially develops. Australian graduating business students were surveyed prior to entry to full‐time work and 2 years later after entry, providing a sample of 213 full‐time employees (average age 23 years). Taking a social cognitive career theory approach, beyond individual and organizational control variables, when new young male or female employees had high outcome expectancies (personal agency), had little family influence and no partner (few barriers), and worked in organizations with an international focus (opportunities), their receptivity to international careers increased compared with when they were students. Appraisals of self‐capabilities (personal agency) appeared relevant dependent on destination. When employees preferred country ease for work, and when as students they had low self‐efficacy for international work, their willingness to relocate to work in developing, but not developed, countries was reduced. Suggesting some factors may not be as relevant for later, as for initial, development of receptivity, outcome expectancies and organizational international focus were not related to increased receptivity in 104 older graduate employees (average age 36 years). The influence of home barriers, organizational focus and self‐capabilities on the development of receptivity to international careers and to working in developing countries was discussed, taking into account age, gender and marital status.
A closer examination of the patterns when coping with work‐related stress: Implications for measurement
Authors: Dewe Philip
Published: December 2003

There is no doubt as to the importance of coping as an explanatory construct when exploring the nature of stress. Nevertheless, understanding the ways in which coping strategies are used, in general, and the role and significance of different patterns of coping, in particular, has been somewhat hampered by conventional measurement practices that involve the simple aggregation of coping strategies into mean scores. The aim of the present study was to explore coping patterns in relation to two emotions, anger and anxiety, using the score profiling technique of sequential tree analysis. The coping patterns to emerge reflected the ‘facilitating’, ‘inhibiting’ and ‘fallback’ role that coping strategies play. These results are discussed in terms of their implications for established measurement practices. If we are to better understand the nature of coping then researchers must now be prepared to take the next step forward and investigate coping using more person‐centred, daily process designs.
Scale structure of the Team Role Self Perception Inventory
Authors: Swailes Stephen , McIntyre‐Bhatty Tim
Published: December 2003

The Team Role Self Perception Inventory (TRSPI) has attracted several studies critical of its psychometric properties. This research uses a large data set and employs confirmatory factor analysis on within‐scale scores to examine the dimensionality and reliability of the TRSPI's scales. Data show that five of the nine scales are unidimensional and that two other scales show generally good fit to a unidimensional solution. The ‘completer‐finisher’ and ‘implementer’ scales show a better fit to a bidimensional structure and would benefit from improved item wording for a small number of items. The ‘shaper’ scale would also benefit from some attention to item wording. Reliability estimates suggest that the reliability of the TRSPI's scales is better than previous estimates imply.
Infrastrukturen für Forschung und Lehre: von nationalen Initiativen zu weltweiten Entwicklungen (Infrastructures for Education and Research: from National Initiatives to Worldwide Development)
Authors: Courtois Bernard
Published: December 2003

Infrastructures to provide access to custom integrated hardware manufacturing facilities are important because they allow students and researchers to access professional facilities at a reasonable cost and they allow companies to access small volume production, otherwise difficult to obtain directly from manufacturers. In the late 70s and early 80s, pioneering integrated circuits multi-chip projects and multi-project wafers initiatives have been launched in Europe, Asia, and North America. Some of these initiatives work together and today a worldwide cooperation has been established by the most experienced. The paper will review these initiatives and the motivations for a global cooperation scheme.
Preparation of 1-(2-pyridylazo)-2-naphthol functionalized benzophenone/naphthalene and their uses in solid phase extractive preconcentration/separation of uranium(VI)
Authors: Preetha C. R. , Prasada Rao T.
Published: December 2003

The preparation of solid reagent 1-(2-pyridylazo)-2-naphthol functionalized benzophenone/naphthalene for preconcentration/separation of uranium (VI) is described. These reagents enriches uranium(VI) quantitatively from dilute aqueous solutions in the pH range 10.5-11.0. The solid mixture consisting of the enriched metal ion along with solid phase extractant were dissolved in 2ml of acetone and uranium(VI) content was established spectrophotometrically by using Arsenazo III procedure. Calibration graphs were rectilinear over the uranium(VI) concentration in the range 0.002-0.1μg cm-3. Five replicate determinations of 40μg of uranium present in 1dm3 of sample solution gave a mean absorbance of 0.185 with a relative standard deviation of 1.4. The detection limit (corresponding to 3 times the standard deviation of the blank) and the enrichment factor were found to be 2μg dm-3 and 500 respectively. Further the possible separation of uranium(VI) from several bivalent, trivalent and tetravalent elements was also established. In addition to validating the developed method by successfully analysing marine sediment reference material (MESS-3), uranium content was established in soil, river and marine sediment samples by the developed method and compared with standard inductively coupled plasma mass spectrometry (ICP-MS) values.
Solubility of crystalline thorium dioxide
Authors: Neck V. , Altmaier M. , Müller R. , Bauer A. , Fanghänel Th. , Kim Jae-Il
Published: December 2003

The solubility of thorium oxides of different crystallinity is investigated at 25°C by different experimental approaches. The dissolution of bulk crystalline ThO2(cr) is a very slow process and the Th(IV) concentrations measured after one year at pH 1-3 in 0.1 and 0.5M HCl-NaCl solutions do not represent equilibrium data. Coulometric titration of thorium nitrate solutions in the low pH range of 1.5-2.5 leads to the formation of microcrystalline ThO2·xH2O(mcr) particles which subsequently agglomerate to a precipitate. The solubility of this solid, in equilibrium with Th4+(aq), is measured from the oversaturation direction. The solubility product is determined to be logK´sp=-49.9±0.4 in 0.5M NaCl corresponding to logK°sp=-53.2±0.4 (converted toI=0 with the SIT). It is close to the thermochemical value for ThO2(cr) and about 6 orders of magnitude lower than that of X-ray amorphous Th(IV) hydroxide or hydrous oxide. The differences in the solubility products are discussed with regard to the particle size and compared with analogous data for U(IV), Np(IV) and Pu(IV).

Above the threshold of hydrolysis of Th4+at pH>2.5, the dissolution of microcrystalline ThO2·xH2O(mcr) is found to be irreversible. In near-neutral to alkaline solutions, the measured thorium concentrations approach those of amorphous Th(OH)4(am). Similar results are obtained with crystalline ThO2(cr) in 0.5M NaCl-NaOH solutions. The solubility is not controlled by the bulk crystalline solid but by amorphous fractions on the surface.
Crystal growth, pyroelectric, piezoelectric, and elastic properties of monoclinic bis (nitrilotriacetato) zirconates X[C(NH2)3] Zr(N(CH2COO)3)2 ⋅ yH2O (y=2 for X=Rb, Tl, NH4; y=1 for X=Cs; y=1.5 for X=CH3NH3)
Authors: Haussühl E. , Haussühl S. , Tillmanns E.
Published: December 2003

Large single crystals of optical quality and with dimensions up to 50 mm of double salts of the type X[C(NH2)3] Zr(N(CH2COO)3)2 ⋅ y H2O (X = Rb, Tl, NH4, Cs, CH3NH3) have been grown from aqueous solutions. They crystallize in the space group P21 and exhibit quasi-isotypic structures. Complete elastic and thermoelastic tensors have been derived from ultrasonic resonances of plane-parallel plates. In addition, thermal expansion, pyroelectric, dielectric and piezoelectric properties have been measured. The maximum longitudinal piezoelectric effects d
222 exceed d
111 of α-quartz roughly by a factor of 7. The pyroelectric constants π
2 surmount π
3 of tourmaline by about a factor of 9. The structural and physical properties are closely related to those of the constituent salts.
Thermal induced transformations on completely Zn2+ exchanged zeolites A and Y
Authors: Weidenthaler C. , Schmidt W.
Published: December 2003

The thermal stability of completely Zn2+ exchanged zeolites A and Y during calcination is studied from R.T. to 1350°C. The phase formation processes are analysed by in situ X-ray diffraction experiments as well as by quenched samples analysed and quantified by Rietveld refinements. The framework structures of the exchanged zeolites A and Y are observed to collapse above 850°C. At higher temperatures the crystallisation of Zn-β-quartz, mullite, and gahnite is initiated from the amorphous phase. Above 1050°C quartz appears and Zn-β-quartz disappears. The crystallisation of willemite is only observed for ZnA, mullite is not stable above 1150°C in both systems. Further increase in temperature leads to the crystallisation of cristobalite accompanied by the disappearance of quartz. The final crystalline components at 1350°C are, for both zeolite precursors, gahnite and cristobalite. Differences between the zeolite precursors are the amounts of amorphous phase formed, indicating a suppression of the formation of a crystalline SiO2 phase in the ZnY samples.
Topological analysis of ionic packings in crystal structures of inorganic sulfides: the method of coordination sequences
Authors: Blatov V. A.
Published: December 2003

Using the concept of coordination sequences and the uniformity criterion the method of topological analysis of atomic packings and of their classification at any degree of metric distortions is implemented in the computer program IsoTest. The criterion is based on the search for packings topologically similar, but not equal to close packings. The topological analysis of ionic sublattices was employed for the crystal structures of 781 inorganic sulfides. It was shown that no less than in the third of cases the sulfides are constructed on the basis of a distorted close packing, and such packings are constructed with sufficiently large cations, as a rule. The examples of forming close packings by complex thioanions contained in a number of thiosalts were drawn.
Are the compressive effects of encapsulation an artifact of the bond valence parameters?
Authors: Krivovichev Sergey V. , Brown I. D.
Published: December 2003

The large bond valence sums found for O2– en-capsulated by Pb2+ ions are shown to result from the use of inappropriate bond valence parameters. New values of r
o = 1.963 Å and b = 0.49 Å are recommended for Pb2+-O bonds.
Structural phase transition of GdGa2 at high pressure
Authors: Schwarz U. , Bräuninger S. , Burkhardt U. , Syassen K. , Hanfland M.
Published: December 2003

Structural properties of the intermetallic compound GdGa2 were investigated under hydrostatic pressures up to 20 GPa using angle dispersive x-ray powder diffraction in combination with the diamond anvil cell technique. At 7.7(5) GPa the onset of a first order phase transition from the AlB2 type structure into a hexagonal high-pressure phase is observed. The transformation is associated with a 2.5 % elongation of the lattice parameter a and an 8 % shortening of c. TB-LMTO bandstructure calculations reveal that the two-dimensional character of the gallium partial structure is preserved in the high-pressure modification.
Elastic and thermoelastic properties of selected organic crystals: acenaphthene, trans-azobenzene, benzophenone, tolane, trans-stilbene, dibenzyl, diphenyl sulfone, 2,2´-biphenol, urea, melamine, hexogen, succinimide, pentaerythritol, urotropine, malonic acid, dimethyl malonic acid, maleic acid, hippuric acid, aluminium acetylacetonate, iron acetylacetonate, and tetraphenyl silicon
Authors: Haussühl S.
Published: December 2003

Elastic and thermoelastic properties of the 21 title crystalline species have been determined from ultrasonic resonant frequencies of plates and their shift upon variation of temperature, respectively. In addition, the tensors of thermal expansion have been measured by the aid of a Fizeau interferometer. An analysis of the elastic behaviour of organic crystals, including earlier elastic data of other organic compounds taken from the literature, revealed common features of organic crystals and organic liquids in respect to the scalar invariantsC= (c11+c22+c33+c44+c55+c66+c12+c13+c23)/9 and d logC/dT,Ttemperature, especially in the case of Van-der-Waals crystals. Contrary to ionic crystals the invariantCincreases in these crystals with larger molecular volume. Crystals with strong hydrogen bonds like dicarboxylic or sulfonic acids behave rather like ionic crystals. The influence of a small molecular elastic stiffness, as observed in plastic crystals, is clearly recognizable in the elastic properties. The impact of structural details on the invariantCand its logarithmic temperature derivative is surprisingly small.
Polytypism in xonotlite Ca6Si6O17(OH)2
Authors: Hejny C. , Armbruster Th.
Published: December 2003

Occurrence, chemistry, crystal growth, technical applications, structure and polytypism of xonotlite Ca6Si6O17(OH)2 are reviewed. Atomic coordinates of the three simplest ordered polytypes in modified Gard notation: Ma2bc (space group P2/a, a = 17.032, b = 7.363, c = 7.012 Å, β = 90.36°), Ma2b2c (space group A2/a, a = 17.032, b = 7.363, c = 14.023, β = 90.36°), and M2a2bc (space group P1̅, a = 8.712, b = 7.363, c = 7.012 Å, α = 89.99° β = 90.36°, γ = 102.18°) were modeled from geometric principles based on the known structure of the M2a2b2c polytype (space group A1̅, a = 8.712, b = 7.363, c = 14.023, α = 89.99 β = 90.36, γ = 102.18°). Unique reflection arrangements in the reciprocal lattice, characteristic of each polytype, were defined as criteria to identify xonotlite polytypes on X-ray single-crystal photographs. Precession- and Weissenberg-photographs of a xonotlite from the Kalahari manganese field (Republic of South Africa) indicated the predominance of the (100) twinned M2a2b2c polytype, followed by the Ma2b2c polytype, and very low concentrations of the Ma2bc polytype. The M2a2bc polytype could not be identified which agrees with previous electron diffraction experiments on xonotlites from other localities. Diffuse streaks parallel to a* and less intensive ones parallel to c* on single-crystal photographs suggest the presence of additional disordered polytypes.
The structure of Co(NH3)6CuCl5 at 10 K
Authors: Bernal I. , Yufit D. S. , Howard J. A. K.
Published: December 2003

The structure of the title compound was determined at 10 K using the Fddd diffractometer equipped with a Mo-target rotating anode. The object of the study was to determine the geometrical parameters of the cation and anion at what we assume is their resting state geometry, given the temperature of data collection. The cation is es-sentially unchanged in geometry from 294 K to 10 K. The anion is considerably distorted, having changed from a trigonal bipyramid (site symmetry 32) to a “T-shaped” or “seesaw” structure, sitting at a two-fold axis. During the cooling process, the space group changed from Fd3̅c to F41/adc. The shape of the anion is, interestingly, similar to that of XeO2F2.
Self-intersecting three-periodic minimal surfaces forming one-periodic tubes or finite polyhedra
Authors: Koch Elke
Published: December 2003

17 families of three-periodic minimal surfaces with straight self-intersections have been derived that subdivideR3into an infinite number of one-periodic 'tubes' and/or finite 'polyhedra'. Their Euler characteristics vary between -3 and -18. Ten of these families show non-orientable minimal surfaces. They subdivideR3either into congruent tubes (eight families), into congruent polyhedra, or into two different kinds of congruent polyhedra. The minimal surfaces of seven families are orientable. All of them cause two different kinds of spatial subunits: two kinds of tubes (one family), tubes and polyhedra (three families), or two different kinds of polyhedra (three families).
The crystal structure of FeInGe2O7
Authors: Bucio J. , Ruvalcaba-Sil J. L. , Rosales I. , García-Robledo J. , Orozco E.
Published: December 2003

A new iron indium germanate has been prepared as polycrystalline powder material which crystallizes in the monoclinic system (S.G. C2/m, No. 12). The structure was characterized by X-ray powder diffraction and Rietveld refinement of the resulting diffraction pattern. The cell parameters are a = 6.5124(4) Å, b = 8.5914(5) Å, c = 4.8936(3) Å, β = 102.683(2)°, V = 267.12(3) Å3 and Z = 2. The structure contains R+3 cations (R=Fe, In) almost equally distributed in distorted RO6 octahedral sites. These octahedra are joined by edge sharing forming a hexagonal arrangement on the ab planes. The RO6 octahedra layers are held together by sheets of isolated Ge2O7 diorthogroups constituted by a double tetrahedra sharing a common vertex. This compound has the thortveitite structure and keeps a strong relationship with the FeYGe2O7 germanate, which presents two R+3 sites with six-coordinated (R=Fe) and seven-coordinated (R=Y) oxygens, corresponding to the different symmetry given by the monoclinic space group P21/m (No. 11)
Prediction of crystal structure of a rare monosaccharide – influence of model geometry
Authors: Ďurík M. , Smrčok L.
Published: December 2003

Crystal structure of a hexagonal monosaccharide, C11H18N2O4, was succesfully predicted by potential energy minimisation. Four starting molecular models differing in ring conformations were based on similar structures and the positions of two substituents (-NH2, -CN) were found by semiempirical AM1 calculations. Generated structures were ranked according to both potential energy values and corre-sponding Rwp
´s. Calculated potential energy was sensitive to changes in the geometries of the sachcharide rings as well as to the positions of substituents. Rigid body Rietveld refinements did not improve accuracy of the crystal structures with low Rwp
´s and high potential energy.
Theoretical analysis and empirical manifestation of the distortion theorem
Authors: Urusov Vadim S.
Published: December 2003

The distortion theorem is analyzed by the use of the Bond Valence Model for the case of an isolated coordination polyhedron with bonds of different lengths. It is shown that a correlation should exist between the average bond length increase and the mean-square deviation of individual bond lengths from the average one, at least for nonstrained crystal structures. It is proved that the correlation parameters are strongly dependent on a mode of distortion (symmetry of coordination environment). These conclusions are in general and sometimes in quantitative agreement with available experimental data, although in most cases the distortion of coordination polyhedra results from a variety of factors of chemical, geometric and electronic origin. It is assumed that an observed correlation between the average bond distance and the distortion degree may be taken as a measure of relative role of intrinsic bond strengths and influence of crystalline environment.
Structure of iron-rich compounds in the Yb–Fe–Al system
Authors: Černý Radovan , Pacheco Vicente , Yanson Tamara , Manyako Michail , Bodak Oxana
Published: December 2003

X-ray diffraction studies on eleven single crystals having compositional ratios close to Yb/(Fe,Al) = 2:17 revealed four distinctly different structures, two having hexagonal symmetry (LuFe9.5 and TbCu7 type) at low and intermediate Al and Yb contents (0–7.5 at Al; 9.6–10.6 at Yb and 11.2–12.5 at Al; 10.5–10.9 at Yb), respectively, and two having rhombohedral symmetry (PrFe7(A) and PrFe7(A + B) types) at high Al and Yb contents (9.8–19.8 at Al; 10.7–11.6 at Yb). All have a common hexagonal TbCu7 type subcell and contain chains made up of Yb and Fe(Al)2 dumbbells running along the c-axis that substitute for each other with various ordering schemes and concentrations. The subcell ratio c/a depends on both the concentration of Fe(Al)2 dumbbells, for which it generally increases, and the structure type (dumbbell order). We define an order parameter capable of describing the dependency of the subcell ratio c/a on the Fe(Al)2 dumbbell ordering, irrespective of structure type, as the probability of finding two Fe(Al)2 dumbbells within a chain that are separated by one Yb atom only. Aluminium substitutes for iron mainly on non-dumbbell sites at low Al contents (LuFe9.5 and TbCu7 type) and enters Fe2 dumbbell sites only at high Al contents (TbCu7 type and PrFe7 type derivatives). The bond distances in the mixed Fe(Al)2 dumbbells increase with increasing Al content. Those in the Fe2 dumbbells depend on the dumbbell order (within one or between different structure types), and less on the Al content of the crystal.
The crystal structure of CaSiO3-walstromite, a special isomorph of wollastonite-II
Authors: Joswig Werner , Paulus Erich F. , Winkler Björn , Milman Victor
Published: December 2003

The crystal structure of CaSiO3-walstromite has been solved and refined by a data set collected in situ from an inclusion in a diamond single crystal (1135 observed reflections, MoKα
, Nonius CAD4, R = 3.46). The crystal structure is almost identical to that of walstromite (Ca2BaSi3O9). The replacement of Ba2+ by Ca2+ causes no significant structural changes (ring silicate; according to F. Liebau: dreier single rings). The structural differences to wollastonite-II (Ca3Si3O9) are also relatively small: The Ca positions are almost the same, but the axial Si3O9-ring is isomorphously replaced by the same ring with the inverse axiality. This constitutes a new principle of isomorphous replacement. Based on density functional theory the equation of state has been predicted. This allows us to estimate the remaining pressure of the investigated CaSiO3 inclusion in the diamond to be ≈3 GPa.
The Freezing of n-Alkanes C15H32 and C17H36: An Unsual Mechanism of Homogeneous Nucleation
Authors: Weidinger Inez , Klein Juliane , Stöckel Peter , Biller E. , Baumgärtel Helmut , Leisner Thomas
Published: December 2003

The nucleation kinetics of n-alkane droplets with carbon numbers of 15 and 17 was observed in an electrodynamic balance. Changes in the elastic light scattering pattern of the single levitated microdroplets indicate the phase transition liquid to solid. Measurements of the nucleation rates gave information on the dynamics of the nucleation process and allow to propose a new mechanism for the nucleation. Large induction times observed for the C15H32 droplets indicate that the nucleation starts after a solid layer has been built up at the surface.
Measurement of the 129Xe NMR Chemical Shift of Supercritical Xenon
Authors: Baumer D. , Fink A. , Brunner E.
Published: December 2003

The measurement of the 129Xe Nuclear Magnetic Resonance (NMR) chemical shift as a function of density is reported. The apparatus used in this study enabled us to measure the 129Xe NMR chemical shift in the supercritical state up to a pressure of about 70 MPa, i.e., a density of 440 amagat1 at 298 K.
The Nonlinear Optical Response of Pt(111) Electrodes in Perchloric Acid Solution: Implications for the Potential of Zero Charge
Authors: Friedrich K. A. , Daum W. , Dederichs F. , Akemann W.
Published: December 2003

Second harmomic and sum frequency generation (SHG, SFG) are used to investigate the second-order non-linear optical response of a Pt(111) single-crystal electrodes in perchloric acid solution. In the potential window between hydrogen evolution and surface oxidation the SHG signal shows a pronounced minimum at 760 mVRHE and rises linearly with decreasing electrode potential. The potential of the minimum as well as the magnitude of the signal in the potential range of hydrogen adsorption depend on the pH of the electrolyte. The dependence of the SHG signal on excitation frequency in the range of 9000–1200 0cm−1 shows a continuous SHG signal increase to higher frequencies without characteristic surface resonances. The SHG signal is assigned to the excitation of a continuum of electronic levels. The maximum of the signal intensity is observed at potentials close to 0 VRHE, where hydrogen evolution takes place and the surface has a maximum of negative charge. Sum-frequency spectra of CO adsorbed on Pt(111) exhibit the known vibrational signature of terminal and bridge-like coordination and an additional resonant signal. On the same surface, the SHG signal is characterized by a high signal intensity which remains constant up to the CO oxidation potential. The potential dependence of the nonlinear response of the Pt(111)/CO surface as well as of the neat surface in perchloric acid indicates a high sensitivity to the surface charge. As a consequence, a negatively charged surface up to a potential of 600 mVRHE is deduced. Our results are at variance with a value for the potential of zero charge of 0.34 VRHE which was derived from the CO charge displacement method, but in agreement with the value based on the immersion technique (U. W. Hamm et al. , J. Electroanal. Chem. 414 (1996) 85).
Investigation of the Pressure Effects on Inclusion Equilibria of Substituted Phenols with β- and γ-Cyclodextrins
Authors: Sueishi Yoshimi , Itami Shotaro
Published: December 2003

The effects of pressure were examined for the inclusion complexation of β- and γ-cyclodextrins (CDs) with 4-substituted phenols. The reaction volume for the CD inclusion complexation with 4-substituted phenols, which is the change in volume accompanied by CD inclusion, was estimated from the pressure dependence of the inclusion equilibria. The reaction volumes estimated for the phenols/β-CD system were positive values in the range of 2.5 and 14.0cm3mol−1, while those for the phenols/γ-CD system were negative in the range of −11.8 and −0.8cm3mol−1. The difference in the reaction volumes for the inclusion complexation of β- and γ-CDs is explained in terms of the difference in the number of water molecules repelled from the CD cavity. Based on the results, the inclusion behavior of CD complexation is discussed.
Behaviour of Some Copper(I) and Cobalt(III) Complexes in Acetonitrile and n-Butyronitrile at 298.15K
Authors: Gill Dip Singh , Pathania Vivek , Vermani Bal Krishan , Sharma Raj Pal
Published: December 2003

Molar conductances of a large number of copper(I) and cobalt(III) complexes, behaving as strong 1:1 electrolytes, have been measured in acetonitrile (AN) and n-butyronitrile (n-BTN) at 298.15K. The conductance data have been analyzed by the Shedlovsky method to evaluate Λ0 and K
A values of these electrolytes. Limiting ion conductances (λ
i

0) for various ions in AN have been calculated by using transference number data. In n-BTN, where no transference number data is available, such values have been calculated by an indirect method using Bu4NBPh4 as a reference electrolyte. The actual ionic radii (ri
) for various ions in solution have been calculated using a modified form of Stokes’ law. The ionic radii (ri
) for various complex ions have been compared with the ionic radii of two reference ions, Bu4N+ and Ph4B−, which are not solvated in dipolar aprotic solvents, to throw light on the solvation behaviour of these complex ions.
Dynamical Structure of Liquid Metals: Recent Theoretical Progress
Authors: Hoshino Kozo
Published: December 2003

Recently, experimental studies on the dynamical structure of liquid metals have been actively carried out by the inelastic X-ray scattering (IXS) technique using the synchrotron radiation which have stimulated theoretical studies. In this paper, recent progress in theoretical studies on the dynamical structure of liquid metals are described in two approaches, i.e. the theoretical approach based on the memory function formalism and the various kinds of computer simulations.
Static and Dynamic Structures of Expanded Fluid Mercury
Authors: Inui Masanori , Tamura Kozaburo
Published: December 2003

X-ray diffraction, small angle X-ray scattering and preliminary inelastic X-ray scattering measurements for a metallic fluid up to the supercritical region have been carried out using synchrotron radiation at SPring-8. We obtained the structure factor,S(k), and the pair distribution functions,g(r), for expanded fluid Hg from the liquid to the dense vapour region by X-ray diffraction measurements. Change of the local structure in the metalinsulator transition in fluid Hg is discussed. To obtain information on the density fluctuation in fluid Hg near the critical point, small angle X-ray scattering measurements were carried out at SPring-8. In addition to the static structures, the dynamic structure factor of expanded fluid Hg was obtained for the first time using inelastic X-ray scattering technique newly established at a synchrotron radiation facility of the third generation source. Preliminary results of the first experiment are presented.
Conductivities, Partial Molar Volumes, and Isentropic Compressibilities of Sodium, Potassium and Ammonium Thiocyanates in Water + N,N-Dimethylformamide Mixtures at 20°C
Authors: Tsierkezos Nikos G. , Molinou Ioanna E.
Published: December 2003

Conductance, ultrasonic velocity, and density measurements are reported for NaSCN, KSCN and NH4SCN in water, N,N-dimethylformamide (DMF), and water + DMF mixtures at 20°C. The limiting molar conductances and association constants have been derived from the Lee–Wheaton conductivity equation. The single-ion conductances have been evaluated using Bu4NBPh4 as the “reference electrolyte”. The limiting molar volumes and apparent isentropic compressibilities have been calculated. The ion–ion and ion–solvent interactions have been discussed.
Clusters in a Saturated Vapor: Pressure-Based Temperature Enhancement of the Cluster Fraction
Authors: Slanina Zdeněk
Published: December 2003

Recent computational findings of temperature increase of clustering degree in different saturated vapors are analyzed. A thermodynamic proof is given and a simple criterion suggested. Illustrations are presented with argon, water, and carbon vapor. Relationships to the fullerene stability island are discussed, too.
Poverty in America 1970–1990: who did gain ground? An application of stochastic dominance criteria employing simultaneous inequality tests in a partial panel
Authors: Anderson Gordon
Published: December 2003

Atkinson (1987) proposed stochastic dominance criteria for analysing poverty which, under certain conditions, establish orderings of states for any poverty line and any poverty measure within given class, refocusing debate on the nature of the income distribution of the poor. Employing new empirical techniques, these criteria are implemented for the United States from 1970 to 1990 using the Panel Study of Income Dynamics. Results highlight the pivotal role of family size scale economies in consumption, indicate different experiences for white versus non‐white groups and suggest that optimism over the progress of the poor is not warranted. Copyright © 2003 John Wiley & Sons, Ltd.
Structural estimates of the intergenerational education correlation
Authors: Belzil Christian , Hansen Jörgen
Published: December 2003

Using a structural dynamic programming model, we investigate the relative importance of family background variables and individual specific abilities in explaining cross‐sectional differences in schooling attainments and wages. Each type of ability is the sum of one component correlated with family background variables and a residual (orthogonal) component which is purely individual specific. Household background variables (especially parents' education) account for 68% of the explained cross‐sectional variations in schooling attainments, while ability correlated with background variables accounts for 17% and pure individual specific ability accounts for 15%. Interestingly, individual differences in wages are mostly explained by pure individual specific abilities as they account for as much as 73% of the explained variations in wages. Family background variables account for only 19%, while ability endowments correlated with family background account for 8%. Copyright © 2003 John Wiley & Sons, Ltd.
A simple iterative method for considering multibounce in PO region of MoM‐PO
Authors: Zhai Huiqing , Liang Changhong
Published: December 2003

It has been shown that the hybrid method of moments physical‐optics (MoM‐PO) approach is an efficient tool to model the electromagnetic behavior of antennas with 3D perfectly conducting bodies of arbitrary shape. In this paper, a simple and effective iterative method is proposed to consider multi‐bounce in the PO region of MoM‐PO. Some numerical results are presented and compared with a reference MoM and conventional MoM‐PO solutions in order to illustrate the high accuracy and efficiency of the proposed approach. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 110–112, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11299
Bent planar monopole operating at GSM/DCS/PCS/IMT2000 quad‐bands
Authors: Low T. K. William , Chen Zhi Ning , Yang Ning
Published: December 2003

In this paper, a compact antenna operating in the GSM/DCS/PCS/IMT2000 quad‐bands is presented. By bending the meandered monopole into three equal and perpendicular sections, then coupling the bent monopole with another strip monopole antenna, the designed novel antenna covers the required bandwidths of GSM (890–960 MHz), DCS (1710–1880 MHz), PCS (1850–1990 MHz) and IMT2000 (1900–2025 MHz). © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 170–172, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11319
Increased nuchal translucency and congenital heart defects in a low‐risk population
Authors: Hafner E. , Schuller T. , Metzenbauer M. , Schuchter K. , Philipp K.
Published: December 2003

Objective

Increased first‐trimester nuchal translucency (NT) is a possible marker for congenital heart defects in euploid fetuses. In this study, we wanted to determine the sensitivity for congenital heart defects using the 95th centile of the NT as a cut‐off point.

Methods

All women who booked for delivery in our hospital in the first trimester underwent NT measurement at a crown‐rump length (CRL) of between 35 and 75 mm. In all euploid fetuses and newborns with isolated or associated CHD, NT was examined retrospectively and classified as normal (<95th centile according to CRL‐dependent centiles in our own data) or increased (≥95th centile).

Results

From a total of 12 978 euploid fetuses screened, 27 had CHD (22 isolated and 5 cases associated with additional malformations). Moreover, 7 of the 27 fetuses also had increased NT (26%). Increased NT was significantly more frequent in fetuses with associated CHD (4/5) than in those with isolated CHD (3/22, Yates corrected χ2p = 0.012). In fact, the relative risk for CHD was 6.6 times higher in fetuses with increased NT compared to those with normal NT.

Conclusion

Increased NT for the detection of CHD performed less well than in other studies. Nevertheless, it can be used as an indication for fetal echocardiography. Copyright © 2003 John Wiley & Sons, Ltd.
Molecular and cytogenetic characterization of extra‐structurally abnormal chromosomes (ESACs) found prenatally: outcome and follow‐up
Authors: Marchina E. , Piovani G. , Vezzola L. , Bellotti D. , Cerri V. , Groli C. , Barlati S.
Published: December 2003

A 40‐year‐old woman underwent amniocentesis at 15.3 weeks of gestation. Chromosome analysis performed using QFQ, DA‐DAPI and CBG banding revealed two de novo extra‐chromosomal markers (ESACs) in 11 of the 16 colonies analysed.

Fluorescence in situ hybridization (FISH) showed that both chromosomes came from the Yq11.22.1 region of the Y chromosome. PCR analysis of genes and STS localized on the Y chromosome excluded the Yp presence specifically of the SRY gene, and most of the euchromatic region of Yq.

After extensive genetic counselling and considering both laboratory and second‐level ultrasound data, the couple decided to continue the pregnancy. At 37.4 weeks of gestational age, a girl weighing 2750 g was born with an Apgar score of 9/10.

A blood sample taken from the umbilical cord showed three cellular lines:mos47,XX, +mar1 ish.der (Y)(wcpY+) [21%]/48,XX, +mar1 ish.der (Y)(wcpY+), +mar2 ish.der (Y)(wcpY+) [41%]/46,XX [38%].

One year after birth, the baby was developing normally and had normal psychomotorial activity. Copyright © 2003 John Wiley & Sons, Ltd.
Predicting complications of pregnancy with first‐trimester maternal serum free‐βhCG, PAPP‐A and inhibin‐A
Authors: Tul Nataša , Pušenjak Stanko , Osredkar Joško , Spencer Kevin , Novak‐Antolič Živa
Published: December 2003

Objective

To find whether fβhCG, PAPP‐A and inhibin‐A levels in maternal serum or fetal nuchal translucency (NT) thickness at the first‐trimester screening for trisomy 21 (T21) might detect women at high risk for adverse pregnancy outcomes.

Methods

A retrospective analysis of 1136 women with singleton pregnancy between 10 and 14 weeks. Women with pregnancy complications were allotted to five subgroups: small for gestational age (SGA), large for gestational age (LGA), gestational diabetes (GDM), hypertensive disorders, preterm delivery; women with normal pregnancy represented the control group. NT, maternal serum fβhCG, PAPP‐A and inhibin‐A were measured. Mann–Whitney test was used for the comparison of fβhCG, PAPP‐A, inhibin‐A and NT between a subgroup of a certain pregnancy complication and the control group. Multivariate logistic regression models were built to explore the relationship among different variables and the occurrence of pregnancy complications.

Results

PAPP‐A values were significantly lower in women who delivered SGA babies (n = 51, 0.76 MoM; p = 0.002) and significantly higher in women who delivered LGA babies (n = 120, 1.12 MoM; p = 0.036). In women with GDM (n = 27), fβhCG, PAPP‐A and inhibin‐A were insignificantly lower than in controls, whereas in women with hypertensive disorders (n = 56) no significant differences between the groups were found. In women with a preterm delivery (<34 weeks) (n = 17), inhibin‐A levels were significantly higher (1.25 MoM; p = 0.015).

Conclusion

Low PAPP‐A level is associated with the delivery of an SGA baby and high PAPP‐A with the delivery of an LGA baby. High inhibin‐A is associated with preterm delivery before 34 weeks. Feto‐placental products in the first trimester do not prove to be useful as a screening tool for predicting pregnancy complications. Copyright © 2003 John Wiley & Sons, Ltd.
Transcervical fetoscopic diagnosis of structural defects in four first‐trimester monochorionic twin intrauterine deaths
Authors: Philipp T. , Separovic E. R. , Philipp K. , Reiner A. , Kalousek D. K.
Published: December 2003

Objective

While chromosomal abnormalities are often the cause of early failed pregnancies, other mechanisms could be involved in monochorionic twin intrauterine deaths, that might be screened for careful morphological analysis.

Methods

Transcervical fetoscopy prior to instrumental evacuation of the uterus was performed in four first‐trimester monochorionic twin intrauterine deaths.

Results

We present fetoscopic and cytogenetic findings in four cases of monochorionic twin intrauterine deaths. In the first, generalized abnormal embryonic development observed in both twins was a manifestation of trisomy 20. The second (thoracophagus) and third (acardius) pair of twins had anomalies peculiar to multiple gestations. The fourth pair of twins was remarkable because of the concordance for the observed limb‐reduction defects.

Conclusion

Malformations of first‐trimester monochorionic twin intrauterine deaths might cover a wide spectrum of etiologies from abnormal chromosomes and single gene defects to rare duplication anomalies. Their detection by careful morphological analysis and the identification of a specific mechanism provides valuable information for genetic counseling and prenatal investigation in a future pregnancy. Copyright © 2003 John Wiley & Sons, Ltd.
Adverse drug reactions in a South Indian hospital—their severity and cost involved
Authors: Ramesh M. , Pandit Jayesh , Parthasarathi G.
Published: December 2003

Purpose

The study was aimed to assess the pattern of occurrence of adverse drug reactions (ADRs) in the local population, severity of reported ADRs and additional financial resource utilisation associated with ADRs.

Methods

This was a prospective, spontaneous reporting study conducted over a period of 7 months by clinical pharmacists. The WHO definition of an ADR was adopted. Each ADR was assessed for its causality by using the WHO Probability Scale. The severity of each reported ADR was assessed using the criterion developed by Hartwig et al. The average cost incurred in treating the ADRs was calculated.

Results

A total of 270 suspected ADRs were reported and evaluated from 164 patients. A total of 3.7% of the hospitalised patients experienced an ADR, 0.7% of the admissions were due to ADRs and 1.8% had a fatal ADR. The gastrointestinal system (36.3%) was most commonly involved with an ADR. The drug class most commonly implicated with ADRs was cardiovascular (18.3%). Majority (47%) of the reactions were ‘moderate’ in severity. The total cost incurred in managing all the reported ADRs was Rs 76 564 (US$ 1595) with an average cost of Rs 690 (US$ 15) per ADR.

Conclusion

Detection and prevention of ADRs at the earliest is very important as they can cause not only morbidity and mortality but also involve high health care cost in their management. Well‐;trained pharmacists in the area of ADR detection, reporting and monitoring could prove as an asset in providing better patient care. Copyright © 2003 John Wiley & Sons, Ltd.
Modified genetic algorithm to model crystal structures: III. Determination of crystal structures allowing simultaneous molecular geometry relaxation
Authors: Bazterra Victor E. , Ferraro Marta B. , Facelli Julio C.
Published: December 2003

The modified genetic algorithm (MGAC) has been extended to allow simultaneous relaxation of molecular geometry during optimization of the crystalline structure. The method was applied to L‐alanine and DL‐alanine for two different potential functions. The genetic algorithm was always able to find minima that are likely global minima of the crystalline potential, showing good agreement with the experimental structures. For DL‐alanine MGAC located the experimental crystalline structure but also consistently found a different low‐energy crystalline structure that it is an excellent candidate for a polymorph. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Ab initio studies of tamoxifen and related compounds
Authors: Huang Ming‐Ju
Published: December 2003

An extensive theoretical study of tamoxifen and related compounds has been performed at the ab initio Hartree–Fock (HF)/6‐31G** and B3LYP/6‐31G** levels. The optimized structures are in good agreement with X‐ray data. Theoretical calculations indicate that the ground state energies of cis‐ and trans‐tamoxifen, as well as the energies of the 4‐hydroxytamoxifen isomeric pair, are close, which confirms experimental and AM1 results and suggests nearly equivalent populations of the two isomers under equilibrium conditions. The effects of solvation were calculated with the Onsager model with full geometry optimization. The results indicate that solvation has little effect on the total energies. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Homology models of the catalytic sites of phosphodiesterase 5A and 10A and molecular docking of selective apoptotic antineoplastic drugs (SAANDs)
Authors: Salter E. A. , Wierzbicki A. , Sperl G. , Thompson W. J.
Published: December 2003

Achieving selective inhibition for individual gene families of cyclic nucleotide phosphodiesterases (CNPDE) isoenzymes has become an important pharmacological goal now that the diversity of these hydrolases has been recognized. Selective apoptotic antineoplastic drugs (SAANDs) induce apoptosis in neoplastic cells and not in normal cells by a mechanism involving inhibition of overexpressed PDEs that hydrolyze cyclic GMP. SAANDs, although not selective, show a preference for PDE5 and PDE10. However, highly selective PDE5 inhibitors do not induce apoptosis. To study differences in PDE inhibitors, we constructed homology models of the target catalytic domains of PDE5A and PDE10A based upon the X‐ray crystal structure of the catalytic domain of PDE4B. Molecular mechanics docking is planned to define new SAANDs vs. ineffective agents. We investigated the binding of exisulind (Aptosyn and other analogs to PDE4, 5, and 10 isoforms using our molecular models and compared the resultant estimated binding energies with experimental IC50 values. Proposed binding orientations for CP 248, a higher‐affinity and more selective inhibitor of PDE5 and PDE10 than exisulind, are presented. The modeling studies described here allowed us to identify some differing structural features of the catalytic pockets that may be helpful in the development of active and more selective drugs to treat tumors found in different tissues while maintaining minimal side effects. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Silicon clusters doped with an yttrium metal atom impurity
Authors: Xiao Chuanyun , Blundell Jessica , Hagelberg Frank , Lester Jr. William A.
Published: December 2003

The structures, energetics, and bonding properties of small Sin (n = 1–6) clusters doped with an yttrium atom are studied by means of a hybrid density functional technique (B3LYP). Close similarity is found between YSin and ScSin clusters in their geometries, size dependences of binding energies and fragmentation energies, charge transfer, spin distribution, and bonding features. It is found important in density functional calculations as well as in Hartree–Fock calculations to examine several different electronic configurations for a given spin multiplicity to determine the most stable configuration because these systems are characterized by small energy gaps and numerous close‐lying states. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Theoretical study of the hydrophobic character of the dimerization of dexanabinol
Authors: Huang Ming‐Ju
Published: December 2003

An extensive theoretical study of the dimers of dexanabinol and related compounds has been performed at the ab initio Hartree–Fock (HF)/6‐31G** and B3LYP/6‐31G** levels. Theoretical calculations indicate that the most stable conformer of dexanabinol does not have intramolecular hydrogen bonds. The most stable dimer of dexanabinol forms intermolecular hydrogen bonds in which the phenol groups act as hydrogen bond donors and the allylic OH groups as acceptors is energetically more favored. The dimer results agree with previous PM3 results. In addition, the interaction of dexanabinol with two water molecules was studied. The effects of solvation were calculated with the Onsager model with full geometry optimization. The solvation results indicate that the most stable dimer of dexanabinol is affected little by solvation. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004