bluuebunny/crossref_metadata_2025 huggingface dataset:
Arsenic, lead, and other trace elements in soils contaminated with pesticide residues at the Hanford site (USA)
Authors: Yokel Jerry , Delistraty Damon A.
Published: March 2003

The primary purpose of this study was to characterize arsenic (As) and lead (Pb) concentrations in former orchard soils contaminated with lead arsenate pesticides at the Hanford site in Washington state (USA). Surface samples (n = 31) were collected from former orchard soils (in cultivation during the pre‐Hanford period) at five locations at the 100 Areas and at one location at the Old Hanford Townsite (OHT). Another set of samples (n = 17) was collected over a soil depth interval of 10–50 cm at the four locations with the highest As and Pb surface concentrations. All samples were analyzed for 22 trace elements (including As and Pb) with inductively coupled plasma–atomic emission spectrometry (ICP–AES). The mean, standard deviation, and range for As in the surface soils were 30, 61, and 2.9–270 mg/kg dry wt, respectively. The corresponding statistics for Pb were 220, 460, and 6.5–1900 mg/kg dry wt, respectively. As and Pb concentrations in the surface soils were positively and significantly correlated (r = 0.91, Bonferroni p < 0.05). Descriptive statistics and bivariate correlations were also computed for other trace elements. As and Pb mean concentrations in the surface soils each differed significantly (p < 0.05) among Hanford locations, with the highest concentrations at the 100‐H and 100‐F Areas. Although both As and Pb mean concentrations decreased with soil depth, regression and correlation coefficients only, for Pb significantly differed from zero (b = −0.0372, r = −0.805, Bonferroni p < 0.05). Compared with data in the literature As and Pb concentrations found in this study exceeded background levels but were typical of orchard soils. Furthermore, mean As and Pb soil concentrations were in the range of various toxicological benchmarks derived for protection of human and ecological receptors. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 104–114, 2003
Three‐dimensional ultrasound fetal lung volume measurement: a systematic study comparing the multiplanar method with the rotational (VOCAL) technique
Authors: Kalache K. D. , Espinoza J. , Chaiworapongsa T. , Londono J. , Schoen M. L. , Treadwell M. C. , Lee W. , Romero R.
Published: March 2003

Objectives

This study was designed to compare a conventional multiplanar technique for three‐dimensional (3D) ultrasound measurement of fetal lung volume with a rotational method using VOCAL™ (Virtual Organ Computer‐aided AnaLysis).

Methods

Thirty‐two fetuses with a variety of conditions at risk for pulmonary hypoplasia were studied. 3D volume data sets of the fetal lungs were acquired using a commercially available ultrasound system. The right and left lung volumes were calculated separately using VOCAL and the multiplanar technique. The level of agreement between two independent observers in categorizing the 3D volume data set as measurable or non‐measurable was determined. The interobserver and intermethod variabilities were also evaluated for both methods.

Results

The intermethod variability was excellent (correlation r = 0.93 and r = 0.96 for the left and right lung, respectively), and there was substantial agreement between the results of both approaches (limits of agreement − 4.4 to 8.9 and − 3.4 to 4.8 mL for the right and left lung, respectively). Fetal lung estimation with VOCAL had a significantly higher interobserver variability than the multiplanar technique. Interobserver agreement in categorizing lung volume data sets as measurable or non‐measurable was lower when VOCAL was used.

Conclusion

Fetal lung volume measurements can be undertaken interchangeably using the multiplanar technique or the rotational method with VOCAL. However, the latter was less reproducible (lower degree of agreement and significantly higher interobserver variability) than the former. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.
Regression modeling of motion with endpoint constraints
Authors: Faraway Julian
Published: March 2003

A statistical model is described for the prediction of reaching motions using motion capture data on a variety of individuals performing reaches to a range of targets. The modeling approach allows for various inputs such as the stature, age and the location of the target to be specified and then computes the predicted trajectories of the kinematic chains of body markers necessary to place an object exactly at the specified target. Functional regression methods for modeling time‐varying angles and other quantities as well as trajectories are described. A new parameterization of posture is described that facilitates the satisfaction of specific endpoints such as placing an object at a target. The methodology is illustrated with an application to two‐handed standing lifts. Copyright © 2003 John Wiley & Sons, Ltd.
Modelling of Offshore Wind Turbine Wakes with the Wind Farm Program FLaP
Authors: Lange Bernhard , Waldl Hans‐Peter , Guerrero Algert Gil , Heinemann Detlev , Barthelmie Rebecca J.
Published: March 2003

The wind farm layout program FLaP estimates the wind speed at any point in a wind farm and the power output of the turbines. The ambient flow conditions and the properties of the turbines and the farm are used as input. The core of the program is an axisymmetric wake model describing the wake behind one rotor. Here an approach based on the simplified Reynolds equation with eddy viscosity closure is chosen. The single‐wake model is combined with a model for the vertical wind speed profile and a wind farm model, which takes care of the interaction of all wakes in a wind farm. The wake model has been extended to improve the description of wake development in offshore conditions, especially the low ambient turbulence and the effect of atmospheric stability. Model results are compared with measurements from the Danish offshore wind farm Vindeby. Vertical wake profiles and mean turbulence intensities in the wake are compared for single‐, double‐ and quintuple‐wake cases with different mean wind speed, turbulence intensity and atmospheric stability. It is found that within the measurement uncertainties the results of the wake model compare well with the measurements for the most important ambient conditions. The effect of the low turbulence intensity offshore on the wake development is modelled well for Vindeby wind farm. Deviations are found when atmospheric stability deviates from near‐neutral conditions. For stable atmospheric conditions both the free vertical wind speed profile and the wake profile are not modelled satisfactorily. Copyright © 2003 John Wiley & Sons, Ltd.
Proteome analysis of recombinant xylose‐fermenting Saccharomyces cerevisiae
Authors: Salusjärvi Laura , Poutanen Marjo , Pitkänen Juha‐Pekka , Koivistoinen Heini , Aristidou Aristos , Kalkkinen Nisse , Ruohonen Laura , Penttilä Merja
Published: March 2003

Introduction of an active xylose utilization pathway into Saccharomyces cerevisiae, which does not naturally ferment pentose sugars, is likely to have a major impact on the overall cellular metabolism as the carbon introduced to the cells will now flow through the pentose phosphate pathway. The metabolic responses in the recombinant xylose‐fermenting S. cerevisiae were studied at the proteome level by comparative two‐dimensional gel electrophoresis of cellular proteins within a pH range of 3–10. Glucose‐limited chemostat cultivations and corresponding chemostat cultivations performed in media containing xylose as the major carbon source were compared. The cultivations were studied in aerobic and anaerobic metabolic steady states and in addition at time points 5, 30 and 60 min after the switch‐off of oxygen supply. We identified 22 proteins having a significant abundance difference on xylose compared to glucose, and 12 proteins that responded to change from aerobic to anaerobic conditions on both carbon sources. On xylose in all conditions studied, major changes were seen in the abundance of alcohol dehydrogenase 2 (Adh2p), acetaldehyde dehydrogenases 4 and 6 (Ald4p and Ald6p), and DL‐glycerol 3‐phosphatase (Gpp1p). Our results give indications of altered metabolic fluxes especially in the acetate and glycerol pathways in cells growing on xylose compared to glucose. Copyright © 2003 John Wiley & Sons, Ltd.
RHO1 (YlRHO1) is a non‐essential gene in Yarrowia lipolytica and complements rho1Δ lethality in Saccharomyces cerevisiae
Authors: León Maela , Jaafar Lahcen , Zueco Jesús
Published: March 2003

The synthesis of β‐1,3‐glucan, the structural component of the yeast cell wall that gives shape to the cell, occurs at the plasma membrane and is the result of the activity of at least a two‐component complex. Fks1p is the catalytic subunit directly responsible for the synthesis of β‐1,3‐glucan, whilst the second subunit, Rho1p, has a GTP‐dependent regulatory role (Yamochi et al., 1994). RHO1 has been characterized in Saccharomyces cerevisiae (Yamochi et al., 1994), and in several other fungal species. In this work, we have used degenerate oligonucleotides derived from the conserved regions of Rho1ps to isolate the RHO1 gene of Yarrowia lipolytica. The gene isolated in this way, which we have named YlRHO1, encodes a 204 amino acid protein that shows a high degree of homology with other Rho1ps. However, unlike S. cerevisiae, the ylrho1Δ disruptant strain in Y. lipolytica is viable, although it exhibits an increased sensitivity to Calcofluor white and Congo red. Also, YlRHO1 complements rho1 lethality in S. cerevisiae at both 28° C and 37° C. The complete sequence of YlRHO1 can be obtained from GenBank under Accession No. AF279915. Copyright © 2003 John Wiley & Sons, Ltd.
Viable Saccharomyces cerevisiae cells at high concentrations cause early growth arrest of non‐Saccharomyces yeasts in mixed cultures by a cell–cell contact‐mediated mechanism
Authors: Nissen Peter , Nielsen Dennis , Arneborg Nils
Published: March 2003

The growth of Kluyveromyces thermotolerans and Torulaspora delbrueckii was examined in mixed cultures with Saccharomyces cerevisiae in YPD modified for wine fermentations. Although the three yeasts had similar maximum specific growth rates in these fermentations, K. thermotolerans and T. delbrueckii arrested growth earlier than S. cerevisiae, thereby obtaining lower stationary phase cell concentrations than S. cerevisiae. Various single and mixed culture fermentations with the three yeasts were carried out in order to find an explanation for this phenomenon. The early growth arrests of K. thermotolerans and T. delbrueckii were absent in single cultures of the two yeasts, and they seemed to be due neither to nutrient limitations nor to the presence of growth‐inhibitory compounds. Rather, they seemed to be due to a cell–cell contact mechanism dependent on the presence of viable S. cerevisiae cells at high concentrations. These results contribute to an increased understanding of why K. thermotolerans and T. delbrueckii arrest growth before S. cerevisiae during wine fermentations. Copyright © 2003 John Wiley & Sons, Ltd.
Zur Kristallstruktur von CaFeF5
Authors: Graulich J. , Massa W. , Babel D.
Published: March 2003

On the Crystal Structure of CaFeF5

Single crystals of CaFeF5 were obtained by heating a mixture of the component fluorides at 860°C for 12 d (a = 549.2(1), b = 1007.6(2), c = 759.9(2) pm, β = 110.02(3)°; space group P21/c, Z = 4). The X‐ray structure redetermination of a twinned specimen confirmed the chain structure of octahedra sharing trans corners already known. But the anomalies reported earlier were removed and less distorted [FeF6] octahedra and [CaF7] pentagonal bipyramids were found, the distances of which are split within the usual range around mean values of Fe—F: 192.4 and Ca—F: 233.1 pm.
Bi37InBr48: Eine polares Subhalogenid mit Bi95+‐Polykationen, komplexen Bromobismutat(III)‐Anionen [Bi3Br13]4— und [Bi7Br30]9— sowie Pentabromoindat(III)‐Anionen [InBr5]2—
Authors: Dubenskyy Vitaly , Ruck Michael
Published: March 2003

Bi37InBr48 wurde in Form schwarzer Kristalle aus Bismut, Indium und BiBr3 durch langsames Abkühlen stöchiometrisch zusammengesetzter Schmelzen von 570 K auf 470 K dargestellt. Aus Röntgenbeugungsuntersuchungen an Pulvern und Einkristallen geht hervor, dass die Verbindung in der Raumgruppe P 63 kristallisiert (a = 2262, 6(4); c = 1305, 6(2) pm). In der polaren Kristallstruktur finden sich Bi95+‐Polykationen in Gestalt stark deformierter, dreifach überkappter, trigonaler Prismen mit genäherter Cs‐Symmetrie. Die hohe Komplexität der Struktur ergibt sich aus der Koexistenz von drei anionischen Baueinheiten: Das trigonale Bromobismutat(III)‐Anion [Bi3Br13]4— besteht aus drei kantenverknüpften [BiBr6]‐Oktaedern. Vier [BiBr6]‐ und drei [BiBr5]‐Polyeder sind über gemeinsame Ecken zur halbschalenförmigen [Bi7Br30]9—‐Gruppierung verknüpft, in die das trigonal‐bipyramidale Pentabromoindat(III)‐Ion [InBr5]2— hineinragt.
Thiosilicate der Selten‐Erd‐Elemente: II. Die nichtzentrosymmetrischen Caesium‐Derivate CsM[SiS4] (M = Sm — Tm)
Authors: Hartenbach Ingo , Schleid Thomas
Published: March 2003

Die Caesium‐Lanthanoid‐Thiosilicate CsM[SiS4] (M = Sm — Tm) kristallisieren allesamt orthorhombisch in der nichtzentrosymmetrischen Raumgruppe P212121 mit vier Formeleinheiten pro Elementarzelle. Ihre Gitterkonstanten bewegen sich in Bereichen von a = 630 — 640 pm, b = 665 — 673 pm und c = 1763 — 1778 pm. Die Darstellung erfolgt durch Umsetzung von Lanthanoid‐Metall (M) mit Schwefel (S) und Siliciumdisulfid (SiS2) mit einem Überschuß von Caesiumchlorid (CsCl) als Reaktand (Cs+‐Quelle) und Flußmittel in evakuierten Kieselglasampullen für sieben Tage bei 850 °C. Die Einkristalle der Titelverbindungen sind ausnahmslos luft‐ und wasserbeständig, zeigen plättchenförmigen Habitus und weisen die Eigenfarbe des jeweiligen Lanthanoid‐Trikations (M3+) mit leicht gelblicher Unterlegung auf. Die Kristallstruktur läßt sich als schichtartiges Arrangement parallel zu (001) beschreiben, in dem anionische {M[SiS4]}—‐Schichten durch Cs+‐Kationen separiert werden. Die M3+‐Kationen sind überkappt trigonal prismatisch von sieben, die Cs+‐Kationen fünffach überkappt trigonal prismatisch von neun plus zwei S2—‐Anionen umgeben. Alle Sulfid‐Anionen gehören ihrerseits annähernd ideal tetraedrischen ortho‐Thiosilicat‐Einheiten [SiS4]4— an.
As12Se44—: ein neuartiges Selenoarsenatanion mit einem Polyarsenkäfig in der Verbindung [Co(NH3)6]2As12Se4 · 12 NH3
Authors: Grothe Michael , Korber Nikolaus
Published: March 2003

Orangefarbene Kristalle der Titelverbindung [Co(NH3)6]2As12Se4 · 12 NH3 wurden durch Reduktion von As4Se4 mit einer Natriumlösung in flüssigem Ammoniak und anschließendes Ausfällen mit CoBr2 gewonnen. Eine Einkristallstrukturanalyse ergibt als anionischen Baustein das Selenoarsenat As12Se44—, welches aus einem zentralen As12‐Käfig besteht, an den exo‐ständig vier formal negativ geladene Selenatome gebunden sind. Die Struktur des As12‐Käfigs entspricht sowohl der zentralen Baueinheit eines bekannten Organopolyphosphans als auch der des tubularen P12‐Stranges in der Verbindung (CuI)3P12.
Neue Hexachalcogeno‐Hypodiphosphate der Erdalkalimetalle und des Europiums
Authors: Jörgens Stefan , Mewis Albrecht , Hoffmann Rolf‐Dieter , Pöttgen Rainer , Mosel Bernd D.
Published: March 2003

Durch Erhitzen der Elementgemenge auf 750 °C (60 h) wurden sechs Hexathio‐ bzw. Hexaseleno‐Hypodiphosphate der Formel M2P2X6 (M = Ca, Sr, Eu, Ba; X = S, Se) dargestellt, deren Kristallstrukturen röntgenographisch mit Einkristallmethoden bestimmt wurden. Eu2P2S6 (a = 9, 396(2), b = 7, 531(2), c = 6, 593(2) Å, β = 91, 48(2) °), Ba2P2S6 (a = 9, 966(1), b = 7, 580(2), c = 6, 737(2) Å, β = 91, 17(3) °), Ca2P2Se6 (a = 9, 664(2), b = 7, 519(2), c = 6, 859(1) Å, β = 92, 02(3) °), Sr2P2Se6 (a = 9, 844(2), b = 7, 788(2), c = 6, 963(1) Å, β = 91, 50(3) °), Eu2P2Se6 (a = 9, 779(2), b = 7, 793(2), c = 6, 957(1) Å, β = 91, 29(3) °) und Ba2P2Se6 (a = 10, 355(2), b = 7, 862(2), c = 7, 046(1) Å, β = 90, 83(3) °) kristallisieren isotyp in der Hochtemperaturform von Sn2P2S6 (P21/n; Z = 2). Die in einer zum Ethan analogen gestaffelten Konformation vorliegenden (P2X6)4—‐Anionen sind über X—M—X‐Kontakte zu einer Raumnetzstruktur verknüpft, wodurch Ca2+, Sr2+ und Eu2+ von 8, Ba2+ dagegen von 8+1 S‐ bzw. Se‐Atomen koordiniert werden. Suszeptibilitätsmessungen an Eu2P2S6 von 2 K bis Raumtemperatur zeigen Curie‐Weiss‐Verhalten mit einem experimentellen magnetischen Moment von 7.43(2) μB/Eu. Bis zu 2 K wurde kein Hinweis auf magnetische Ordnung gefunden. Ein 151Eu Mössbauer‐Spektrum bei 77 K zeigt nur ein Signal bei einer Isomerieverschiebung von δ = —12.6(1) mm/s. Somit kann auf stabil zweiwertiges Europium in Eu2P2S6 geschlossen werden.
Ternary Indides RE4Pd10In21 (RE = La, Ce, Pr, Nd, Sm) — Synthesis, Structure, and Physical Properties
Authors: Zaremba Vasyl' I. , Rodewald Ute Ch. , Kalychak Yaroslav M. , Galadzhun Yaroslav V. , Kaczorowski Dariusz , Hoffmann Rolf‐Dieter , Pöttgen Rainer
Published: March 2003

The ternary indium compounds RE4Pd10In21 (RE = La, Ce, Pr, Nd, Sm) were synthesized from the elements in glassy carbon crucibles in a high‐frequency furnace. Single crystals of Sm4Pd10In21 were obtained from an indium flux. An arc‐melted precursor alloy of the starting composition ∼SmPd3In6 was annealed with a slight excess of indium at 1200 K followed by slow cooling (5 K/h) to 870 K. All compounds were investigated by X‐ray powder diffraction and the structures were refined from single crystal diffractometer data. The RE4Pd10In21 indides are isotypic with Ho4Ni10Ga21, space group C2/m: a = 2314.3(2), b = 454.70(7), c = 1940.7(2) pm, β = 133.43(2)°, wR2 = 0.0681, 1678 F2 values for La4Pd10In21, a = 2308.2(1), b = 452.52(4), c = 1944.80(9) pm, β = 133.40(1)°, wR2 = 0.0659, 1684 F2 values for Ce4Pd10In21, a = 2303.8(2), b = 450.78(4), c = 1940.6(1) pm, β = 133.39(1)°, wR2 = 0.0513, 1648 F2 values for Pr4Pd10In21, a = 2300.2(2), b = 449.75(6), c = 1937.8(2) pm, β = 133.32(1)°, wR2 = 0.1086, 1506 F2 values for Nd4Pd10In21, and a = 2295.6(2), b = 447.07(4), c = 1935.7(1) pm, β = 133.16(1)°, wR2 = 0.2291, 2350 F2 values for Sm4Pd10In21, with 108 variables per refinement. All palladium atoms have a trigonal prismatic coordination. The strongest bonding interactions occur for the Pd—In and In—In contacts. The structures are composed of covalently bonded three‐dimensional [Pd10In21] networks in which the rare earth metal atoms fill distorted pentagonal channels. The crystal chemistry and chemical bonding in these indides is briefly discussed. Magnetic susceptibility measurements show diamagnetism for La4Pd10In21 and Curie‐Weiss paramagnetism for Ce4Pd10In21, Pr4Pd10In21, and Nd4Pd10In21. The neodymium compound orders antiferromagnetically at TN = 4.5(2) K and undergoes a metamagnetic transition at a critical field of 1.5(2) T. All the RE4Pd10In21 indides studied are metallic conductors.
Ordnungsvarianten in ternären Chalkogeniden mit aufgefüllter β‐Manganstruktur
Authors: Kienle Lorenz , Duppel V. , Simon A. , Deiseroth H. J.
Published: March 2003

In ternären Chalkogeniden mit aufgefüllter β‐Manganstruktur besteht die Tendenz zur Ausbildung unterschiedlicher Ordnungsvarianten. Im Falle der Verbindungen AM6Te10 (A = Ca, Sn, Pb; M = Al, Ga) und A2M6Ch10 (Na2Ga6Te10, Na2Ga6Se10 und der neuen Verbindung Na2In6Se10) sind unterschiedliche Voraussetzungen für das Auftreten möglicher Varianten gegeben. Hochauflösende Elektronenmikroskopie (HRTEM) und Elektronenbeugung an AM6Te10 belegen die Existenz von Ordnungsvariationen der Kationen in den metaprismatischen Lücken von makroskopisch scheinbar homogenen Proben. Neben vollständig geordneten Domänen werden auch Kristallite mit nur partiell geordneter Struktur nachgewiesen. Im Falle der Verbindungen A2M6Ch10 bilden sich die Strukturvarianten ausschließlich durch Variationen der Tetraederlückenbesetzung mit M3+. Präparativen Zugang zu diesen Ordnungsvarianten erhält man durch die direkte Substitution von M3+, die in dieser Arbeit im Mittelpunkt steht. Die komplexen Ordnungsvarianten können in kristallographischen Gruppe‐Untergruppe‐Beziehungen systematisiert werden. Detaillierte Analysen unterstreichen die enge topologische Verwandtschaft dieser Phasen zum Aristotyp (β‐Mangan) und belegen, daß M3+ in allen Strukturen unterschiedliche Lücken des gleichen Typs besetzt (T4 und T5).
Ein Erdalkalimetallpolyphosphid ungewöhnlicher Zusammensetzung: Die Kristallstruktur von Ba5P9
Authors: Eisenmann Brigitte , Rößler Ute
Published: March 2003

Die metallisch dunkelgraue, sehr hydrolyseempfindliche Verbindung Ba5P9 lässt sich aus der Stöchiometrie entsprechenden Gemengen der Elemente erhalten. Sie kristallisiert orthorhombisch in der Raumgruppe Fdd2 (a = 1562, 6(1) pm, b = 1896, 8(2) pm, c = 1027, 2(2) pm; Z = 8). In der Kristallstruktur liegen P9‐Kettenfragmente vor, die von den Ba‐Kationen separiert werden. Bei ionischer Formulierung resultiert für das Anion die Ladung 10‐, nach der (8‐N)‐Regel sind aber 11 Elektronen zur Valenzabsättigung nötig. Nach magnetischen Messungen ist das P9‐Anion kein Radikal, so dass eine Stabilisierung über Doppelbindungen zu diskutieren ist.
Untersuchungen zum System SmOBr/SeO2
Authors: Oppermann H. , Schmidt P. , Quoc H. Dao , Popovkin B. A. , Berdonosov P. S. , Dolgikh V. A.
Published: March 2003

Die Existenz der quaternären Verbindungen SmSeO3Br, SmSe2O5Br und SmSe3O7Br im thermodynamischen Gleichgewicht wurde erstmals nachgewiesen. Nach Festkörperreaktionen von Gemengen SmOBr und SeO2 wurde die Phasen durch Röntgendiffraktometrie und IR‐Spektroskopie charakterisiert. Durch Gesamtdruckmessungen und DTA wurden das Zustandsdiagramm und das Zustandsbarogramm des quasibinären Schnittes SmOBr/SeO2 aufgestellt.

Aus der Temperaturabhängigkeit der Zersetzungsdrücke wurden die Bildungsenthalpien und Standardentropien der Phasen hergeleitet. Zudem wurden die Bildungsenthalpien der Phasen aus den Daten der Lösungskalorimetrie der Phasen sowie von SmOBr und SeO2 gewonnen.

Aus den Gesamtdruckmessungen erhält man:

ΔH(SmSeO3Brf, 298) = —308, 0 ± 5, 5 kcal/mol

S°(SmSeO3Brf, 298) = 46, 0 ± 5, 0 cal/K · mol

ΔH(SmSe2O5Brf, 298) = —373, 7 ± 7, 0 kcal/mol

S°(SmSe2O5Brf, 298) = 53, 4 ± 8, 0 cal/K · mol

ΔH(SmSe3O7Brf, 298) = —424, 6 ± 10, 0 kcal/mol

S°(SmSe3O7Brf, 298) = 75, 9 ± 11, 0 cal/K · mol

Durch Lösungskalorimetrie in 4n HBr wurden gewonnen:

ΔH°B(SmOBrf, 298) = —229, 4 ± 1, 0 kcal/mol

ΔH°B(SmSeO3Brf, 298) = —298, 7 ± 2, 6 kcal/mol

ΔH°B(SmSe2O5Brf, 298) = —356, 9 ± 2, 5 kcal/mol

ΔH°B(SmSe3O7Brf, 298) = —415, 2 ± 3, 0 kcal/mol

SmSe2O5Br und SmSe3O7Br schmelzen peritektisch bei 350 °C bzw. 600 °C. SmSeO3Br weist zwei Phasenübergänge bei 160 °C (g‐b) and 375 °C (b‐a) auf.
Changing Principles in European Social Security
Authors: Clasen Jochen , Van Oorschot Wim
Published: March 2003

The provision of social security benefits rests on normative principles of social justice. Most strongly manifest in earnings-related social insurance, the principle of reciprocity has been increasingly questioned on grounds of equity, adequacy and fiscal viability, in the wake of socio-economic changes (e.g. post-industralisation, globalisation) and political developments (e.g. Europeanisation). Universalist programmes seem extraordinarily expensive under tight public budgets, and could be criticised as inequitable at a time when middle classes increasingly rely on individual and occupational forms of income security. The principle of need appears to have become more prominent within modern European social security systems keen on targeting resources.

Is there empirical evidence which would reflect these alleged trends? Concentrating on three principles inherent in social security transfers (need, universalism and reciprocity) the major concerns of this article are conceptual and empirical. First, it addresses the problem of operationalising social security principles and delineating indicators of change over time. Second, it applies two of these indicators in order to identify and compare the extent to which the three principles have gained or lost prominence since the early 1980s, with empirical evidence taken from the Netherlands, United Kingdom, Germany and Scandinavia.

The article argues first that, applying either indicator, there is no cross-national trend towards squeezing reciprocity-based social insurance, but that a convergence between erstwhile strong (Bismarckian) and weak (Beveridgean) principled programmes can be identified. Second, a clear trend towards needs-based social security can be identified within the ‘legal’ but not within the ‘volume’ perspective, at least in some programmes and some claimant groups. This is due to both policy changes and favourable labour market conditions. Third, two countries indicate very diverse trends. British social security is distinctive in terms of the erosion of Beveridgean reciprocity, as well as the growing strength of the needs principle. In the Netherlands, there have been considerable shifts in principles underlying certain programmes, but no general trend in either direction can be observed. On the whole, Dutch social security continues to exhibit a strong mix of principles.
Trends of Poverty and Income Inequality in Cross-National Comparison
Authors: Ritakallio Veli-Matti
Published: March 2003

Comparative research on poverty, income inequality and the effectiveness of income transfer systems has flourished during the last two decades, largely owing to the contribution of the Luxembourg Income Study. So far, however, the majority of comparative analyses have been based on a single year. In this paper, we have analysed cross-national patterns of poverty and income inequality with special emphasis on their stability. We examine trends in poverty and income inequality between 1980 and 1995 in nine countries representing three different ideal types of social policy.

The differences in poverty among the countries studied correspond with the respective models of social policy more clearly in the mid-1990s than they did 15 years earlier. Generally speaking, the poverty rate is slightly under 5 per cent in the Nordic countries, around 7.5 per cent in Central Europe, 10 per cent in Canada, 12.5 per cent in the UK, and as high as 17.5 per cent in the USA.

In all countries included in the analysis, the primary distribution – based on market income – has become less equal than before. In each country, the proportion of the population able to achieve subsistence from the market alone has decreased continuously. This trend is more significant than the change in actual poverty, which means that the absolute poverty-alleviating impact of income redistribution systems became stronger in these countries during the period 1980–1995.

The analysis of income inequality produced a similar picture. In comparison to poverty, however, the change is rather less extensive. The Nordic countries, in particular, have been able to respond to the rise in market income differences so that the income inequality for disposable incomes has hardly increased at all. Canada shows a parallel trend. The USA and, in particular, the UK reflect a movement in the opposite direction.

Trends in poverty in various population groups are analysed. By 1995 poverty had turned into a risk for young adults in all the countries studied. The poverty rate increased for the 18–30 age-group in all countries, while an opposite trend was observed among the elderly, in particular those aged over 65. The poverty rate among the elderly is now below the average population rate in all the countries studied.
Positive and Negative Interactions among Individuals of a Root Hemiparasite
Authors: Matthies D.
Published: March 2003

Abstract: I studied the effects of a wide range of densities on establishment, survival, growth and reproduction of the annual root hemiparasite Rhinanthus alectorolophus in a field experiment. Seeds of the parasite were sown with those of a mixture of grassland plants as potential hosts. In most plants, seedling survival is strongly reduced by self‐thinning at high densities, but in R. alectorolophus the proportion of seeds producing a young plant increased linearly with sowing density, indicating positive interactions among seedlings. Because survival to maturity was not influenced by density, the number of flowering plants per seed sown also increased with density. In contrast, mean plant size and reproduction were strongly reduced at high densities. It is suggested that resource sharing among parasites connected by haustoria is the most likely mechanism responsible for the reduced mortality of seedlings at high densities. The results indicate that facilitation among cohorts of conspecific root hemiparasites can increase the recruitment of young plants. The number of seeds produced per seed sown (a multiplicative fitness measure) was, however, independent of density in Rhinanthus because the early positive effects of density on recruitment were compensated later by the negative effects of crowding on growth and reproduction. Increased survival of seedlings could, however, indirectly increase fitness because it will increase the genetic diversity of offspring and may thus, for instance, reduce the impact of pathogens.
The impact of parietal cells onHelicobacter pyloritropism and host pathology: An analysis using gnotobiotic normal and transgenic mice
Authors: Syder Andrew J. , Oh Jung D. , Guruge Janaki L. , O'Donnell David , Karlsson Maria , Mills Jason C. , Björkholm Britta M. , Gordon Jeffrey I.
Published: March 2003

Helicobacter pyloriinfection of the human stomach is common and typically benign, although a subset of hosts develops severe pathology. Infection occurs in an organ with distinct microenvironments characterized by pronounced differences in the composition of acid-producing parietal cells. In this study, we examine determinants of bacterial tropism to various gastric niches by using germ-free normal and transgenic mice with an engineered parietal cell ablation. Mice were colonized for 8 weeks with a clinical isolate (Hp1) that expresses adhesins recognized by epithelial NeuAcα2,3Galβ1,4 glycan receptors. In normal mice, Hp1 has tropism for a parietal cell-deficient niche where sialylated glycans are expressed by a narrow band of pit cells positioned at the boundary between the squamous epithelium (forestomach) and the proximal glandular epithelium. Lymphoid aggregates that develop in this niche, but not elsewhere in the stomach, were analyzed by GeneChip and quantitative RT-PCR studies of laser capture microdissected mucosa and yielded a series of biomarkers indicative of immune cell activation and maturation. Genetic ablation of parietal cells produced a new source of NeuAcα2,3Galβ1,4 glycans in amplified gastric epithelial lineage progenitors, with accompanying expansion of Hp1 within the glandular epithelium. Lymphoid aggregates that develop in this formerly acid-protected epithelium have molecular features similar to those observed at the forestomach/glandular junction. These findings demonstrate the important roles played by parietal cells and glycan receptors in determining the positioning ofH. pyloriwithin the gastric ecosystem, and emphasize the need to consider the evolution of pathology within a given host in a niche-specific context.
The matrix attachment region in the Chinese hamster dihydrofolate reductase origin of replication may be required for local chromatid separation
Authors: Mesner L. D. , Hamlin J. L. , Dijkwel P. A.
Published: March 2003

Centered in the Chinese hamster dihydrofolate reductase origin of replication is a prominent nuclear matrix attachment region (MAR). Indirect lines of evidence suggested that this MAR might be required for origin activation in early S phase. To test this possibility, we have deleted the MAR from a Chinese hamster ovary variant harboring a single copy of the dihydrofolate reductase locus. However, 2D gel replicon mapping shows that removal of the MAR has no significant effect either on the frequency or timing of initiation in this locus. Rather, fluorescence
in situ
hybridization studies on cells swollen under either neutral or alkaline conditions show that deletion of the MAR interferes with local separation of daughter chromatids. This surprising result provides direct genetic evidence that at least a subset of MARs performs an important biological function, possibly related to chromatid cohesion and separation.
Antigen presentation by keratinocytes directs autoimmune skin disease
Authors: Fan Lian , Busser Brian W. , Lifsted Traci Q. , Lo David , Laufer Terri M.
Published: March 2003

The antigen-presenting cells that initiate and maintain MHC class II-associated organ-specific autoimmune diseases are poorly defined. We now describe a new T cell antigen receptor (TCR) transgenic (Tg) model of inflammatory skin disease in which keratinocytes activate and are the primary target of autoreactive CD4+T cells. We previously generated keratin 14 (K14)-Aβbmice expressing MHC class II only on thymic cortical epithelium. CD4+T cells from K14-Aβbmice fail to undergo negative selection and thus have significant autoreactivity. The TCR genes from an autoreactive K14-AβbCD4 hybridoma were cloned to produce a TCR Tg mouse, 2-2-3. 2-2-3 TCR Tg cells are negatively selected in WT C57BL/6 mice but not in 2-2-3/K14-Aβbmice. Interestingly, a significant number of mice that express both the K14-Aβbtransgene and the autoreactive 2-2-3 TCR spontaneously develop inflammatory skin disease with mononuclear infiltrates, induction of MHC class II expression on keratinocytes, and T helper 1 cytokines. Disease can be induced by skin inflammation but not solely by activation of T cells. Thus, cutaneous immunopathology can be directed through antigen presentation by tissue-resident keratinocytes to autoreactive TCR Tg CD4+cells.
High-throughput approach for detection of DNA bending and flexibility based on cyclization
Authors: Zhang Yongli , Crothers Donald M.
Published: March 2003

We have developed a high-throughput approach to the labor-intensive problems of DNA cyclization, which we use to characterize DNA curvature and mechanical properties. The method includes a combinatorial approach to make the DNA constructs needed and automated real-time measurement of the kinetics using fluorescence. We validated the approach and investigated the flexibility of two kinds of nicked DNA and AT dinucleotide repeats. We found that, although the nicks hardly alter the bending flexibility, they significantly increase the torsional flexibility, and that the AT repeat has 28% (±12%) lower bending rigidity than a generic DNA sequence.
Gene–environment interaction modulated by allelic heterogeneity in inflammatory diseases
Authors: Chamaillard Mathias , Philpott Dana , Girardin Stephen E. , Zouali Habib , Lesage Suzanne , Chareyre Fabrice , Bui The Hung , Giovannini Marco , Zaehringer Ulrich , Penard-Lacronique Virginie , Sansonetti Philippe J. , Hugot Jean-Pierre , Thomas Gilles
Published: March 2003

CARD15
is a major susceptibility gene for a frequent multifactorial chronic inflammatory bowel disorder, Crohn disease (CD). By using NF-κB activation assays, the cytosolic CARD15 was shown to efficiently detect bacterial peptidoglycan (PGN), reminiscent of the PGN recognition protein surveillance mechanism in
Drosophila
. The 3 CD-associated variants and 13 additional variants carried by CD patients demonstrated impaired PGN-dependent response revealing null, hypomorphic, or dominant-negative properties. Quantitative parametrization of this response, computed from the patients'
CARD15
genotypes, was predictive of several variable CD manifestations. In contrast,
CARD15
alleles associated with Blau's syndrome promoted PGN-independent NF-κB activation, an observation that accounts for the minimal microbial input in the etiology of this dominant, monogenic inflammatory disorder affecting solely aseptic sites.
The impact of the certainty context on the process of choice
Authors: Dickhaut John , McCabe Kevin , Nagode Jennifer C. , Rustichini Aldo , Smith Kip , Pardo José V.
Published: March 2003

In this study we examine how the introduction of a reference lottery with nonrandom outcomes alters the way in which choices among pairs of lotteries are made, even if it does not alter the choices. We use different domains (some of the lotteries produce gains, other losses) and different contexts (one member of the pair, the reference lottery, may be either risky or certain). In our experiment, the change from gain to loss domain affects choices: subjects are risk averse in the gain domain, but not in the loss domain. On the contrary, the context effect of the certain lottery does not affect choices. However, the introduction of the certainty reference lottery affects two behavioral variables, response time and brain activation, in a dramatic way. This result suggests that the certainty lottery promotes a different process through which preferences are revealed, even if the differences among lotteries may not be large enough to induce different choices.
The 1.6-Å crystal structure of the class of chaperones represented by
Escherichia coli
Hsp31 reveals a putative catalytic triad
Authors: Quigley Paulene M. , Korotkov Konstantin , Baneyx François , Hol Wim G. J.
Published: March 2003

Heat shock proteins (Hsps) play essential protective roles under stress conditions by preventing the formation of protein aggregates and degrading misfolded proteins. EcHsp31, the
yedU
(
hchA
) gene product, is a representative member of a family of chaperones that alleviates protein misfolding by interacting with early unfolding intermediates. The 1.6-Å crystal structure of the EcHsp31 dimer reveals a system of hydrophobic patches, canyons, and grooves, which may stabilize partially unfolded substrate. The presence of a well conserved, yet buried, triad in each two-domain subunit suggests a still unproven hydrolytic function of the protein. A flexible extended linker between the A and P domains may play a role in conformational flexibility and substrate binding. The α-β sandwich of the EcHsp31 monomer shows structural similarity to PhPI, a protease belonging to the DJ-1 superfamily. The structure-guided sequence alignment indicates that Hsp31 homologs can be divided in three classes based on variations in the P domain that dramatically affect both oligomerization and catalytic triad formation.
Myosin isoforms show unique conformations in the actin-bound state
Authors: Volkmann Niels , Ouyang Greta , Trybus Kathleen M. , DeRosier David J. , Lowey Susan , Hanein Dorit
Published: March 2003

Crystallographic data for several myosin isoforms have provided evidence for at least two conformations in the absence of actin: a prehydrolysis state that is similar to the original nucleotide-free chicken skeletal subfragment-1 (S1) structure, and a transition-state structure that favors hydrolysis. These weak-binding states differ in the extent of closure of the cleft that divides the actin-binding region of the myosin and the position of the light chain binding domain or lever arm that is believed to be associated with force generation. Previously, we provided insights into the interaction of smooth-muscle S1 with actin by computer-based fitting of crystal structures into three-dimensional reconstructions obtained by electron cryomicroscopy. Here, we analyze the conformations of actin-bound chicken skeletal muscle S1. We conclude that both myosin isoforms in the nucleotide-free, actin-bound state can achieve a more tightly closed cleft, a more downward position of the lever arm, and more stable surface loops than those seen in the available crystal structures, indicating the existence of unique actin-bound conformations.
Functional proteomics of nonalcoholic steatohepatitis: Mitochondrial proteins as targets of
S
-adenosylmethionine
Authors: Santamaría Enrique , Avila Matías A. , Latasa M. Ujue , Rubio Angel , Martín-Duce Antonio , Lu Shelly C. , Mato José M. , Corrales Fernando J.
Published: March 2003

Recent work shows that
S
-adenosylmethionine (AdoMet) helps maintain normal liver function as chronic hepatic deficiency results in spontaneous development of steatohepatitis and hepatocellular carcinoma. The mechanisms by which these nontraditional functions of AdoMet occur are unknown. Here, we use knockout mice deficient in hepatic AdoMet synthesis (
MAT1A
−/−
) to study the proteome of the liver during the development of steatohepatitis. One hundred and seventeen protein spots, differentially expressed during the development of steatohepatitis, were selected and identified by peptide mass fingerprinting. Among them, 12 proteins were found to be affected from birth, when
MAT1A
−/−
expression is switched on in WT mouse liver, to the rise of histological lesions, which occurs at ≈8 months. Of the 12 proteins, 4 [prohibitin 1 (PHB1), cytochrome
c
oxidase I and II, and ATPase β-subunit] have known roles in mitochondrial function. We show that the alteration in expression of PHB1 correlates with a loss of mitochondrial function. Experiments in isolated rat hepatocytes indicate that AdoMet regulates PHB1 content, thus suggesting ways by which steatohepatitis may be induced. Importantly, we found the expression of these mitochondrial proteins was abnormal in
ob/ob
mice and obese patients who are at risk for nonalcoholic steatohepatitis.
Heparin-binding EGF-like growth factor and ErbB signaling is essential for heart function
Authors: Iwamoto Ryo , Yamazaki Satoru , Asakura Masanori , Takashima Seiji , Hasuwa Hidetoshi , Miyado Kenji , Adachi Satoshi , Kitakaze Masafumi , Hashimoto Koji , Raab Gerhard , Nanba Daisuke , Higashiyama Shigeki , Hori Masatsugu , Klagsbrun Michael , Mekada Eisuke
Published: March 2003

The heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) is a member of the EGF family of growth factors that binds to and activates the EGF receptor (EGFR) and the related receptor tyrosine kinase, ErbB4. HB-EGF-null mice (HB
del/del
) were generated to examine the role of HB-EGF
in vivo
. More than half of the HB
del/del
mice died in the first postnatal week. The survivors developed severe heart failure with grossly enlarged ventricular chambers. Echocardiographic examination showed that the ventricular chambers were dilated and that cardiac function was diminished. Moreover, HB
del/del
mice developed grossly enlarged cardiac valves. The cardiac valve and the ventricular chamber phenotypes resembled those displayed by mice lacking EGFR, a receptor for HB-EGF, and by mice conditionally lacking ErbB2, respectively. HB-EGF–ErbB interactions in the heart were examined
in vivo
by administering HB-EGF to WT mice. HB-EGF induced tyrosine phosphorylation of ErbB2 and ErbB4, and to a lesser degree, of EGFR in cardiac myocytes. In addition, constitutive tyrosine phosphorylation of both ErbB2 and ErbB4 was significantly reduced in HB
del/del
hearts. It was concluded that HB-EGF activation of receptor tyrosine kinases is essential for normal heart function.
Long-term correction of globotriaosylceramide storage in Fabry mice by recombinant adeno-associated virus-mediated gene transfer
Authors: Park Jinhee , Murray Gary J. , Limaye Advait , Quirk Jane M. , Gelderman Monique P. , Brady Roscoe O. , Qasba Pankaj
Published: March 2003

Fabry disease is an X-linked recessive inborn metabolic disorder characterized by systemic and vascular accumulation of globotriaosylceramide (Gb
3
) caused by a deficiency of the lysosomal enzyme α-galactosidase A (α-gal A). The condition is associated with an increased morbidity and mortality due to renal failure, cardiac disease, and early onset of stroke. Hemizygous males are primarily affected clinically with variable expression in heterozygous females. Gene-therapy trials have been initiated recently in α-
gal A
knockout mouse models of Fabry disease by using a variety of viral vectors. In the present investigation we administered single i.v. injections of 1 × 10
10
genomes of recombinant adeno-associated virus (rAAV) encoding the human α-
gal A
gene driven by a modified chicken β-actin (CAG) promoter to α-
gal A
knockout (Fabry) mice. Transgenic mice were analyzed for expression of α-gal A activity and Gb
3
levels in liver, kidney, heart, spleen, small intestine, lung, and brain. Administration of the rAAV-CAG-hAGA vector resulted in stable expression of α-gal A in organs of the Fabry mice for >6 months. α-Gal A activity in the organs became equal to or higher than that of wild-type mice. Accumulated Gb
3
in the liver, heart, and spleen was reduced to that of wild-type mice with lesser but significant reductions in kidney, lung, and small intestine. Injection of the rAAV-CAG-hAGA construct into skeletal muscle did not result in expression of α-
gal A
in it or in other tissues. This study provides a basis for a simple and efficient gene-therapy approach for patients with Fabry disease and is indicative of its potential for the treatment of other lysosomal storage disorders.
Significance and therapeutic potential of the natriuretic peptides/cGMP/cGMP-dependent protein kinase pathway in vascular regeneration
Authors: Yamahara Kenichi , Itoh Hiroshi , Chun Tae-Hwa , Ogawa Yoshihiro , Yamashita Jun , Sawada Naoki , Fukunaga Yasutomo , Sone Masakatsu , Yurugi-Kobayashi Takami , Miyashita Kazutoshi , Tsujimoto Hirokazu , Kook Hyun , Feil Robert , Garbers David L. , Hofmann Franz , Nakao Kazuwa
Published: March 2003

Natriuretic peptides (NPs), which consist of atrial, brain, and C-type natriuretic peptides (ANP, BNP, and CNP, respectively), are characterized as cardiac or vascular hormones that elicit their biological effects by activation of the cGMP/cGMP-dependent protein kinase (cGK) pathway. We recently reported that adenoviral gene transfer of CNP into rabbit blood vessels not only suppressed neointimal formation but also accelerated reendothelialization, a required step for endothelium-dependent vasorelaxation and antithrombogenicity. Accordingly, we investigated the therapeutic potential of the NPs/cGMP/cGK pathway for vascular regeneration. In transgenic (Tg) mice that overexpress BNP in response to hindlimb ischemia, neovascularization with appropriate mural cell coating was accelerated without edema or bleeding, and impaired angiogenesis by the suppression of nitric oxide production was effectively rescued. Furthermore, in BNP-Tg mice, inflammatory cell infiltration in ischemic tissue and vascular superoxide production were suppressed compared with control mice. Ischemia-induced angiogenesis was also significantly potentiated in cGK type I Tg mice, but attenuated in cGK type I knockout mice. NPs significantly stimulated capillary network formation of cultured endothelial cells by cGK stimulation and subsequent Erk1/2 activation. Furthermore, gene transfer of CNP into ischemic muscles effectively accelerated angiogenesis. These findings reveal an action of the NPs/cGMP/cGK pathway to exert multiple vasculoprotective and regenerative actions in the absence of apparent adverse effects, and therefore suggest that NPs as the endogenous cardiovascular hormone can be used as a strategy of therapeutic angiogenesis in patients with tissue ischemia.
Transcriptional network controlled by the trithorax-group gene
ash2
in
Drosophila melanogaster
Authors: Beltran Sergi , Blanco Enrique , Serras Florenci , Pérez-Villamil Beatriz , Guigó Roderic , Artavanis-Tsakonas Spyros , Corominas Montserrat
Published: March 2003

The transcription factor
absent
,
small
, or
homeotic discs 2
(
ash2
) gene is a member of the trithorax group of positive regulators of homeotic genes. Mutant alleles for
ash2
are larval/pupal lethals and display imaginal disc and brain abnormalities. The allele used in this study is a true mutant for the trithorax function and lacks the longest transcript present in wild-type flies. In an attempt to identify gene targets of
ash2
, we have performed an expression analysis by using cDNA microarrays. Genes involved in cell cycle, cell proliferation, and cell adhesion are among these targets, and some of them are validated by functional and expression studies. Even though trithorax proteins act by modulating chromatin structure at particular chromosomal locations, evidence of physical aggregation of
ash2
-regulated genes has not been found. This work represents the first microarray analysis, to our knowledge, of a trithorax-group gene.