bluuebunny/crossref_metadata_2025 huggingface dataset:
When hearts, hands, and feet trump brains: Centralist versus peripheralist responses in children and adults
Authors: Winer Gerald A. , Cottrell Jane E. , Bica Lori A.
Published: June 2008

A series of studies examined the presence of centralist versus peripheralist responding about the physical location of psychological processes. Centralists respond that processes such as cognition and emotion are a function of the brain. Peripheralists respond that such processes are located in other parts of the body, such as the heart. Although peripheralist responses declined across grade levels, even older children and adults often gave peripheralist answers, depending on the context of the questions. Peripheralist responses occurred when participants were asked about the effect of switching irrelevant body parts between two people and when they were asked to choose a different body part among four choices. Results also showed adults' responses varied with different contextual cues. The findings support a coexistence model of development which argues for the simultaneous presence of developmentally advanced reasoning or scientifically based knowledge along with presumably less advanced, intuitive‐based reasoning, or folk beliefs.
Capabilities of chemical simulation methods in the elucidation of structure and dynamics of solutions
Authors: Hofer Thomas S. , Pribil Andreas B. , Randolf Bernhard R.
Published: June 2008

As a result of recent methodological developments in connection with enhanced computational capacity, theoretical methods have become increasingly valuable and reliable tools for the investigation of solutions. Simulation techniques utilizing a quantum mechanical (QM) approach for the treatment of the chemically most relevant region so-called hybrid quantum mechanical/molecular mechanical (QM/MM) simulations have reached a level of accuracy that often equals or may even surpass experimental methods. The latter is true in particular whenever ultrafast (i.e., picosecond) dynamics prevail, such as in labile hydrates or structure-breaking systems. The recent development of an improved QM/MM framework, the quantum mechanical charge field (QMCF) ansatz, enables a broad spectrum of solute systems to be elucidated. As this novel methodology does not require any solute solvent potential functions, the applicability of the QMCF method is straightforward and universal. This advantage is bought, however, at the price of a substantial increase of the QM subregion, and an attendant increase in computational periods to levels of months, and even a year, despite parallelizing high-performance computing (HPC) clusters. Molecular dynamics (MD) simulations of chemical systems showing increasing complexity have been performed, and demonstrate the superiority of the QMCF ansatz over conventional QM/MM schemes. The systems studied include Pd2+, Pt2+, and Hg22+, as well as composite anions such as PO43-and ClO4-.
Coarse-graining in suspensions of charged nanoparticles
Authors: Dahirel Vincent , Jardat Marie , Dufrêche Jean-François , Lucas Ivan , Durand-Vidal Serge , Turq Pierre
Published: June 2008

A coarse-grain description of nanocolloidal suspensions in the presence of an added salt is presented here. It enables us to simulate trajectories of the nanoparticles from effective functions that depend on average densities of salt ions. In practice, the ion-averaged effective potential is used as input of a Brownian dynamics (BD) simulation. This potential may be derived by various methods, ranging from purely analytical to fully numerical ones. For the description of dynamical properties, this simulation also requires an effective diffusion coefficient that must be calculated or experimentally determined, and that accounts for the effects of microions on the mobility of the nanoparticles. The different versions of our coarse-graining procedure are applied to the case of a maghemite suspension, for which an explicit description of all ions would be very time-consuming.
What can be learnt from dielectric relaxation spectroscopy about ion solvation and association?
Authors: Buchner Richard
Published: June 2008

Ion solvation and ion association are key features of ion-solvent interactions, and their balance largely determines structure, thermodynamics, and dynamics of electrolyte solutions. Despite being studied for many years with various techniques, these effects are still intriguing because too often results obtained with different methods-each having its individual merits and limitations-cannot be connected properly due to lacking information. In this contribution, we would like to bring dielectric relaxation spectroscopy (DRS) as a further tool for solution studies to the attention of the audience. The principles of DRS and the required instrumentation are briefly introduced. The major focus will be on the kind of results obtained with this technique regarding ion solvation and association and how this information compares with results obtained from other techniques.
Polyelectrolyte hydration: Theory and experiment
Authors: Vlachy Vojko
Published: June 2008

A short review of recent theoretical and experimental advances in studies of polyelectrolyte solutions is presented. The focus is on ion-specific effects as revealed in measurements of osmotic pressure and enthalpy of dilution. We review the experimental results for two different polyelectrolyte systems: (i) salts of polyanetholesulfonic acid, and (ii) aliphatic ionenes (polycations) in aqueous solution with various counterions. A theoretical approach based on the extension of Wertheim's integral equation theory [J. Stat. Phys.35, 19 (1984)] is used to analyze the experimental data. Preliminary results, based on the all-atom simulation of model 3,3 ionene oligomers, are discussed in the light of polyelectrolyte hydration.
Ionic interactions in aqueous mixtures of hydrophilic and -phobic ions
Authors: Kumar Anil
Published: June 2008

Ions of both hydrophilic and -phobic nature play a pivotal role in biological systems and during synthesis of many organic molecules. However, the interaction of a hydrophilic ion with a hydrophobic one is not a simple physical process and is useful in understanding the rate enhancement in organic transformations and thermal stability of DNA and RNA. During the talk, an attempt was made to present some of the experimental work on aqueous mixtures of these ions carried out at National Chemical Laboratory, Pune, and give a theoretical interpretation of the binary, ternary, and quaternary interactions operating in these systems. The contribution of these interaction terms to the excess free energy of mixing, ΔmGE, will be analyzed.
Isoequilibrium relationships and cooperative effects in spin-state transitions in solution
Authors: Hassan Nader , Koudriavtsev Andrei B. , Linert Wolfgang
Published: June 2008

Thermal induced spin transitions between low- and high-spin states of Fe(II) complexes are commonly observed in the solid state. Cooperative effects, such as abrupt and two-step spin crossover, are typical for these objects and arise from intermolecular interactions described by several formalisms. These phenomena appear as deviations from the linearity of the respective van't Hoff plots. In solutions, molecular interactions manifest themselves in isoequilibrium relationships (IERs) as well as in a few cases of specific deviations of van't Hoff plots from linearity. The nature of these phenomena will be discussed on the basis of a statistical-thermodynamic model of spin crossover.
Synthesis and stability of wroewolfeite, Cu4SO4(OH)6·2H2O
Authors: Dabinett Timothy R. , Humberstone David , Leverett Peter , Williams Peter A.
Published: June 2008

Titration of aqueous copper(II) sulfate solutions with aqueous NaOH at temperatures ranging from 0 to 25 °C results in a complex Ostwald step rule cascade of basic copper sulfate phases. At 25 °C, the thermodynamically stable phase is brochantite [Cu4SO4(OH)6], but posnjakite [Cu4SO4(OH)6·H2O] is formed first. At lower temperatures, but above 0 °C, wroewolfeite [Cu4SO4(OH)6·2H2O] forms first. If left in contact with the reaction solution, wroewolfeite is converted to posnjakite and brochantite in turn. However, at 0 °C, synthetic wroewolfeite is stable for periods longer than a week, even in contact with the reaction solution, and a stability constant could be determined for its formation. For the reaction below, lg K = -16.3(1) at 0 °C and I = 0, as determined by solution methods.

0.25Cu4SO4(OH)6·2H2O(s,wroewolfeite) = Cu2+(aq) + 0.25SO4
2-(aq) + 1.5OH-(aq) + 0.5H2O(l)

Stability relations between minerals of stoichiometry Cu4SO4(OH)6·2H2O (n = 0, 1, 2) are discussed. High concentrations of Mg2+ ions (1 M) prevent the isolation of wroewolfeite at any temperature down to 0 °C.
Ternary mixtures of phosphonium ionic liquids + organic solvents + water
Authors: Chowdhury Shahana A. , Scott Janet L. , MacFarlane Douglas R.
Published: June 2008

Ionic liquids (ILs) and water are both potentially green solvents that are useful in a variety of extraction processes. This report presents the ternary phase diagrams and tie-line data of trihexyl(tetradecyl)phosphonium dicyanamide [P6,6,6,14][DCA], phosphonium bis(2,4,4-trimethylpentyl)phosphinate [P6,6,6,14][((CH3)3C5H8)2PO2], and 1-ethyl-3-methylimidazolium ethylsulfate [emim][C2H5SO4] ILs in organic solvents (ethanol, acetonitrile, toluene) and water. [P6,6,6,14][DCA] and [P6,6,6,14][((CH3)3C5H8)2PO2] tended to yield emulsions when combined with water and ethanol, while [emim][C2H5SO4] combined with toluene and water provided two clear phases of reasonable viscosity. The compositions of the ternary mixtures were determined to obtain the tie-lines. A noticeable difference was observed for the tie-lines of the same IL (e.g., [P6,6,6,14][DCA]) with different organic solvents (ethanol and acetonitrile) and water mixtures. In all cases, the addition of ethanol eventually produced a single phase.
The adjoint L-function of GL(4)
Authors: Bump Daniel , Ginzburg David
Published: June 2008

We exhibit a Rankin-Selberg integral for the fifteen-dimensional adjoint L-function of GL(4).
3D-2D asymptotic analysis of an optimal design problem for thin films
Authors: Fonseca Irene , Francfort Gilles
Published: June 2008

The Gamma-limit of a rescaled version of an optimal material distribution problem for a cylindrical two-phase elastic mixture in a thin three-dimensional domain is explicitly computed. Its limit is a two-dimensional optimal design problem on the cross-section of the thin domain; it involves optimal energy bounds on two-dimensional mixtures of a related two-phase bulk material. Thus, it is shown in essence that 3D-2D asymptotics and optimal design commute from a variational standpoint.
Integral modular categories and integrality of quantum invariants at roots of unity of prime order
Authors: Masbaum G , Wenzl H
Published: June 2008

It is shown how to deduce integrality properties of quantum 3-manifold invariants from the existence of integral subcategories of modular categories. The method is illustrated in the case of the invariants associated to classical Lie algebras constructed in [42], showing that the invariants are algebraic integers provided the root of unity has prime order. This generalizes a result of [31], [32] and [29] in the sl2-case. We also discuss some details in the construction of invariants of 3-manifolds, such as the S-matrix in the PSUk case, and a local orientation reversal principle for the colored Homfly polynomial.
Invariant subspaces of given index in Banach spaces of analytic functions
Authors: Borichev Alexander
Published: June 2008

For a wide class of Banach spaces of analytic functions in the unit disc including all weighted Bergman spaces with radial weights and for weighted ℓAp spaces we construct z-invariant subspaces of index n, 2 ≦ n ≦ + ∞, without common zeros in the unit disc.
Sur la répartition des points rationnels de surfaces elliptiques
Authors: Billard Hervé
Published: June 2008

Nous étudions la répartition des points rationnels de surfaces elliptiques fibrées au dessus de la droite projective admettant une section. Nous déterminons la densité des points rationnels de telles surfaces dont un multiple appartient à une section. Dans le cas où la surface est birationnelle au plan projectif (sur le corps des rationnels), nous déduisons qu'il existe une infinité de fibres dont le rang est supérieur d'au moins une unité au rang générique.
Analytic functions on Zariski open sets, and local cohomology
Authors: Kisin Mark
Published: June 2008

We give a new proof of a theorem of Siu and Trautmann on the vanishing of cohomology with support on complex or rigid analytic spaces. We indicate how our methods might be used to prove various comparison theorems in algebraic and analytic geometry.
Projective normality and syzygies of algebraic surfaces
Authors: Gallego F. J , Purnaprajna B. P
Published: June 2008

In this work we develop new techniques to compute Koszul cohomology groups for several classes of varieties. As applications we prove results on projective normality and syzygies for algebraic surfaces. From more general results we obtain in particular the following:

Mukai's conjecture (and stronger variants of it) regarding projective normality and normal presentation for surfaces with Kodaira dimension 0, and uniform bounds for higher syzygies associated to adjoint linear series,

effective bounds along the lines of Mukai's conjecture regarding projective normality and normal presentation for surfaces of positive Kodaira dimension, and,

results on projective normality for pluricanonical models of surfaces of general type (recovering and strengthening results by Ciliberto) and generalizations of them to higher syzygies.

In addition, we also extend the above results to singular surfaces.
The affine curve-lengthening flow
Authors: Andrews Ben
Published: June 2008

The motion of any smooth closed convex curve in the plane in the direction of steepest increase of its affine arc length can be continued smoothly for all time. The evolving curve remains strictly convex while expanding to infinite size and approaching a homothetically expanding ellipse.
Weights of Markov traces on Hecke algebras
Authors: Orellana R. C
Published: June 2008

We compute the weights, i.e. the values at the minimal idempotents, for the Markov trace on the Hecke algebra of type Bn and type Dn. In order to prove the weight formula, we define representations of the Hecke algebra of type B onto a reduced Hecke algebra of type A. To compute the weights for type D we use the inclusion of the Hecke algebra of type D into the Hecke algebra of type B.
The Pfaffian closure of an o-minimal structure
Authors: Speissegger Patrick
Published: June 2008

Every o-minimal expansion of the real field has an o-minimal expansion in which the solutions to Pfaffian equations with definable C1 coefficients are definable.
Symplectic cutting of Kähler manifolds
Authors: Braverman Maxim
Published: June 2008

We obtain estimates on the character of the cohomology of an S1-equivariant holomorphic vector bundle over a Kähler manifold M in terms of the cohomology of the Lerman symplectic cuts and the symplectic reduction of M. In particular, we prove and extend inequalities conjectured by Wu and Zhang.

The proof is based on constructing a flat family of complex spaces Mt (t ∈ ℂ) such that Mt is isomorphic to M for t
≠ 0, while M0 is a singular reducible complex space, whose irreducible components are the Lerman symplectic cuts.
Homotopy colimits – comparison lemmas for combinatorial applications
Authors: Welker Volkmar , Ziegler Günter M , Živaljević Rade T
Published: June 2008

We provide a “toolkit” of basic lemmas for the comparison of homotopy types of homotopy colimits of diagrams of spaces over small categories. We show how this toolkit can be used in quite different fields of applications. We demonstrate this with respect to

Björner's “Generalized Homotopy Complementation Formula” [5],

the topology of toric varieties,

the study of homotopy types of arrangements of subspaces,

the analysis of homotopy types of subgroup complexes.
A local-to-global principle for deformations of Galois representations
Authors: Böckle Gebhard
Published: June 2008

Given an absolutely irreducible Galois representation : GE → GLN (k), E a number field, k a finite field of characteristic l > 2, and a finite set of places Q of E containing all places above l and ∞ and all where ∞ ramifies, there have been defined many functors representing strict equivalence classes of deformations of such a representation, e.g. by Mazur or Wiles in [15] or [26], with various conditions on the behaviour of the deformations at the places in Q and with the condition that the deformations are unramified outside Q. Those functors are known to be representable. For as above, our goal is to present a rather general class of global deformation functors that satisfy local deformation conditions and to investigate for those, under what conditions the global deformation functor is determined by the local deformation functors.

We will give precise conditions under which the local functors for all places in Q are sufficient to describe the global functor, first in a coarse form, then in a refined form using auxiliary primes as done by Taylor and Wiles in [24]. This has several consequences. The strongest is that one can derive ring theoretic results for the universal deformation space by Mazur if one uses results of Diamond and Wiles, cf. [11] and [26], and if one has a good understanding of all local situations. Furthermore it is easier to understand what happens under increasing the ramification as done by Boston and Ramakrishna in [6] and [20], [21]. Finally we shall reinterpret the results in the case of a tame representation by directly considering presentations of certain pro-l Galois groups and revisiting the prime-to-adjoint principle of Boston, cf. [5].
Castelnuovo-Mumford regularity bound for smooth threefolds in ℙ5 and extremal examples
Authors: Kwak Si-Jong
Published: June 2008

Let X be a nondegenerate integral subscheme of dimension n and degree d in ℙN defined over the complex number field ℂ. X is said to be k-regular if Hi(ℙN, ℐX (k – i)) = 0 for all i ≧ 1, where ℐX is the sheaf of ideals of ℐℙN and Castelnuovo-Mumford regularity reg(X) of X is defined as the least such k. There is a well-known conjecture concerning k-regularity: reg(X) ≦ deg(X) – codim(X) + 1. This regularity conjecture including the classification of borderline examples was verified for integral curves (Castelnuovo, Gruson, Lazarsfeld and Peskine), and an optimal bound was also obtained for smooth surfaces (Pinkham, Lazarsfeld). It will be shown here that reg(X) ≦ deg(X) – 1 for smooth threefolds X in ℙ5 and that the only extremal cases are the rational cubic scroll and the complete intersection of two quadrics. Furthermore, every smooth threefold X in ℙ5 is k-normal for all k ≧ deg(X) – 4, which is the optimal bound as the Palatini 3-fold of degree 7 shows. The same bound also holds for smooth regular surfaces in ℙ4 other than for the Veronese surface.
Nicht-invasive Diagnostik kolorektaler Tumore – Hat der Guaiac-Test ausgedient? / Non-invasive detection of colorectal cancer – do we still need the guaiac-based fecal occult blood test?
Authors: Stein Jürgen , Loitsch Stefan M. , Shastri Yogesh
Published: June 2008

Aufgrund der leichten Handhabung und des Nachweises einer Mortalitätssenkung gilt der Nachweis von okkultem Blut (FOBT) im Stuhl derzeit als das am weitesten verbreitete Screeningverfahren für das kolorektale Karzinom. Als nachteilig erweisen sich allerdings eine unzureichende Sensitivität, insbesondere beim Nachweis früher Stadien und eine nach wie vor geringe Akzeptanz in der Bevölkerung. Vorläufige Daten zum Nachweis von Calprotectin oder der Tumor-M2-PK im Stuhl ließen bessere Screeningeigenschaften erwarten. Aber auch hier schränkt die geringe Sensitivität für frühe Vorstufen und unzureichende Spezifität mit zu erwartenden hohen Folgekosten die Tauglichkeit der Tests deutlich ein. Die kürzlich entwickelten immunologischen FOBTs (I-FOBT) erweisen sich als spezifischer und sensitiver. Sie beruhen auf dem Nachweis von humanem Hämoglobin mittels spezifischer Antikörper und sind somit unabhängig von diätetischen oder medikamentösen Faktoren, was zu einer deutlich besseren Akzeptanz führt. Sie gelten derzeit als kosteneffektivste Verfahren unter den nichtinvasiven Screeningmaßnahmen. Der Nachweis von Tumor-DNA im Stuhl eröffnet eine neue Ära zum frühzeitigen Nachweis kolorektaler Karzinome. Erste kleinere Studien weisen auf eine sehr gute Sensitivität dieser Verfahren hin. Sie lagen für kolorektale Karzinome zwischen 62–91% und für Adenome zwischen 26–73% bei mit 93–100% sehr guter Spezifität. Als nachteilig im Vergleich zu den derzeit verfügbaren Screeningtests erweisen sich allerdings die vergleichsweise hohen Kosten.
Ankündigung/Announcement
Authors: Horstmann Frau K.
Published: June 2008

No Abstract available
Determination of CD4 lymphocyte percentages using a new simplified and affordable no lyse flow cytometric protocol: a pilot study / Bestimmung der Lymphozyten-abhängigen CD4-Prozentwerte mit Hilfe eines neuen, vereinfachten und kostengünstigen, durchflusszytometrischen Protokolls ohne Lyse: Eine Testuntersuchung
Authors: Greve Burkhard , Cassens Uwe , Baumann Claudia , Sibrowski Walter , Kuling Gudrun , Szabados Florian , Schlenke Peter , Reichelt Doris , Gebauer Wolfgang , Göhde Wolfgang
Published: June 2008

Although the pathogenesis of HIV infection is independent of age, specific considerations have to be taken into account for the treatment of infants, children and adolescents. In addition to more cautious drug therapy, it is proposed to follow up disease progression by repeated measurement of CD4 lymphocyte percentage (CD4%). Unfortunately, this requires complicated, expensive analytical techniques and complex sample preparation protocols. This is one of the reasons why treatment of the increasing number of children suffering from HIV/AIDS in developing countries remains a challenge. We evaluated a new and simplified no lyse no wash protocol to measure CD4% on a volumetric flow cytometer. Eight blood samples of healthy and HIV-infected individuals were sent to five German hospital laboratories (centres B–F) and were measured by their flow cytometric in-house techniques. The results were compared to those of centre A using the volumetric technique with the new sample preparation protocol. Comparative data with established protocols and flow cytometric techniques showed good correlations for the determination of leukocytes and for lymphocytes. Comparing CD4% results of centre A (new protocol and volumetric measuring technique) with the highest and lowest values of centres B–F by Bland-Altman analysis yielded a bias of –1.02% (SD 3.16) and 4.27% (SD 3.72) over the whole range (4.01%–70.56%), respectively. A comparably simple three-step protocol as introduced for absolute CD4+ cell count can be used to calculate CD4% only by the addition of two antibodies (CD4 and CD45). The cost per test is in the range of €2.50 and therefore far below current prices of €15.00–€40.00.
Monitoring of CMV-specific T-cell levels after organ transplantation / Monitoring CMV-spezifischer T-Zellen nach Organtransplantation
Authors: Sester Martina , Gärtner Barbara C. , Sester Urban
Published: June 2008

Based on the systemic and life-long need for immunosuppressive drug therapy, patients after organ transplantation suffer from an increased risk of infectious complications and disease due to primary infection or reactivation with the human cytomegalovirus (CMV). In contrast, CMV infections in immunocompetent individuals are usually clinically silent. In recent years, significant advances have been made in the development of novel experimental approaches to quantify antigen-specific T-cells on the single cell level. These assays have been extensively characterised and evaluated as a novel diagnostic measure to analyse the individual immunocompetence towards CMV in a clinical setting. A close correlation was found between decreasing frequencies of CMV-specific T-cells and increasing viral load, whereas CMV-specific T-cells were stable in the absence of viral replication. Due to easy technical performance, limited sample volume and short processing times, the combined monitoring of CMV-specific T-cells and viral load represents a valuable diagnostic tool to identify patients at risk for CMV-related complications after organ transplantation.
Vergleichende Untersuchung verschiedener D-Dimer-Tests zum Ausschluss thromboembolischer Erkrankungen unter klinischen Routinebedingungen / Comparative evaluation of different D-dimer assays for exclusion of venous thromboembolism in a clinical routine setting
Authors: Roggenbuck Lennart , Dörner Klaus
Published: June 2008

In einer prospektiven Studie an 246 konsekutiven Ambulanzpatienten mit Verdacht auf thromboembolische Erkrankung (VTE) untersuchten wir das aktuelle Leistungsvermögen von vier D-Dimer-Tests (D-Dimer plus, Stratus CS, Innovance, alle Siemens Medical Solutions Diagnostics sowie Tina-quant D-Dimer, Roche Diagnostics) zum Ausschluss von VTE. Ausgangspunkt unserer Untersuchung war das Auftreten von drei falsch negativen D-Dimerbefunden bei Ambulanzpatienten mit gesicherter VTE innerhalb kürzerer Zeit.

Diagnostische Sensitivitäten und Spezifitäten sowie positive und negative prädiktive Werte der D-Dimer-Tests wurden auf Basis der herstellerempfohlenen Cut-off-Werte sowie der Obergrenze des jeweiligen 95%-Konfidenz-intervalls (95% CI) um diesen Cut-off berechnet.

Bei 46 Patienten (18,7%) ließ sich mit bildgebenden Verfahren eine VTE nachweisen. Der D-Dimer-plus-Test zeigte bei sieben (unter Berücksichtigung des 95% CI bei neun) von 46 Patienten falsch negative Ergebnisse (Sensitivität 84,8% bzw. 80,4%, negativer prädiktiver Wert 93,8% bzw. 93,0%) bei insgesamt niedriger Messsignaldynamik. Mit den drei alternativen Tests ließen sich in diesem Kollektiv keine falsch negativen Befunde nachweisen (Sensitivität und negativer prädiktiver Wert jeweils 100%).

Nur durch eine enge klinische Rückkopplung lassen sich Leistungsdefizite bereits etablierter Testsysteme erfassen. Bei entsprechendem Verdacht sind weitere Untersuchungen zur Klärung durch das Labor, auch in Übereinstimmung mit der aktuellen Akkreditierungsnorm DIN EN ISO 15189 zu fordern.
Natürliche Killerzellen und Natürliche Killer-T-Zellen bei Nierentransplantation / Natural killer cells and natural killer-T cells in patients with renal transplantation
Authors: Hoppe Anett , Kamprad Manja , Wegmann Claudia , Wötzel Michael , Hauss Johann , Emmrich Frank , Fangmann Josef , Sack Ulrich
Published: June 2008

Die Nierentransplantation als etabliertes Verfahren zur Behandlung des terminalen Nierenversagens birgt trotz hoher klinischer Standards besonders im postoperativen Bereich das Risiko zahlreicher Komplikationen. Dabei spielen besonders Rejektionsereignisse und bakterielle, virale sowie mykotische Infektionen eine Rolle. Oftmals sind deren rechtzeitige klinische sowie labordiagnostische Erkennung und die daraus resultierenden therapeutischen Konsequenzen zu ungenau. In der vorliegenden Arbeit wird daher ein praxisnahes Konzept für ein immunologisches Monitoring innerhalb von 28 Beobachtungstagen nach erfolgter Transplantation unter Einbeziehung der Natürlichen Killerzellen (NK) und Natürlichen Killer-T-Zellen (NKT-Zellen) beschrieben. Mittelpunkt des Monitorings ist dabei die durchflusszytometrische Bestimmung der funktionellen Marker NKp30, NKp44, NKp46, CD16 und CXCR3 auf NK- und NKT-Zellen. Beide Zellpopulationen wurden durch die Therapie beeinflusst. Während sich Lebend- und Leichenspende kaum unterschieden und keine signifikanten Unterschiede zwischen den verwendeten Immunsuppressiva gefunden wurden, ergaben sich insbesondere bei den NKT-Zellen Befunde, die eine diagnostische Nutzung dieser Zellen im Transplantatmonitoring möglich erscheinen lassen. Der Verlauf dieser Zellen nach Nierentransplantation weist typische Veränderungen unter Standardimmunsuppression auf und erlaubt die Erkennung von postoperativen Komplikationen.
Diagnostic value of peripheral blood markers for acute rejection in liver transplanted-patients receiving anti IL-2R antibodies / Diagnostik der akuten Rejektion mittels peripherer Blutparameter bei lebertransplantierten Patienten unter IL-2 Rezeptorantikörper basierter Immunsuppression
Authors: Weimann Andreas , Eisele Robert M. , Pawellek Sebastian , Hippler-Benscheid Michael , Rüggeberg Anne , Cammann Henning , Radke Cornelia , Müller Christian , Klupp Jochen , Sack Ulrich , Lun Andreas
Published: June 2008

Background: T-cell activation markers in peripheral blood are helpful to detect acute rejection in liver transplantation (LTX) patients with immunosuppression by Cyclosporin A or Tacrolimus. Immunosuppression including basiliximab may influence the diagnostic value of T-cell markers.

Methods: In the present study, 80 LTX patients receiving immunosuppressive treatment based on induction with basiliximab were monitored as well as clinical examination with conventional (liver enzymes, cholesterol, bilirubin, prothrombin time, leukocyte count and differentiation) and immunologic markers [soluble interleukin (IL)-2 receptor, IL-8, lymphocyte subpopulations] during the first 3 weeks after transplantation. In total, 15 patients suffered from acute rejection, 34 patients had no complications, and 31 patients suffered from other complications including infections, poor graft function or renal failure.

Results: Cholesterol, prothrombin time and CD3+/CD4–/CD8– lymphocytes allowed for discrimination between the group with acute rejection and patients suffering from other complications. Furthermore, significant time-dependent changes between both groups were found for alanine amino transferase (ALT), soluble IL-2 receptor (sIL-2R), eosinophils, lymphocytes and CD3+/CD4–/CD8– lymphocytes. In contrast, receiver operating characteristic (ROC) curve analysis for diagnostic relevance revealed only a Youden index >0.5 for prothrombin. When combining cholesterol, lymphocyte count, sIL-2R and time courses of ALT, eosinophils and sIL-2R, diagnostic efficacy could be maximized to a Youden index of 1.0.

Conclusion: Despite significant differences between several single parameters, diagnostic application of the laboratory results requires a combination of a broad panel including the analysis of time courses to distinguish groups suffering from acute rejection or other complications. The complexity of this approach may limit its application in clinical practice.
A variant of the IGF-I gene is associated with blood pressure but not with left heart dimensions at the age of 2 years: the Generation R Study
Authors: van Houten Vera A A , Mook-Kanamori Dennis O , van Osch-Gevers Lennie , Steegers Eric A P , Hofman Albert , Moll Henriëtte A , van Duijn Cornelia M , Helbing Willem A , Hokken-Koelega Anita C S , Jaddoe Vincent W V
Published: June 2008

Background and objective

A common variant of the IGF-I gene has been shown to be associated with cardiovascular disease in adulthood. The objective of this study was to examine whether this variant of the IGF-I gene is associated with blood pressure and left heart dimensions in early childhood.

Research design and methods

This study was embedded in the Generation R Study, a population-based prospective cohort study from foetal life onwards. IGF-I promoter region was genotyped in DNA obtained from cord blood. Blood pressure (systolic and diastolic) and echocardiography (left ventricular mass, left atrial diameter and aortic root diameter) measurements were performed at the age of 2 years. Analyses were performed in 538 subjects.

Results

Eight alleles of the IGF-I promoter region were identified. In total, 43% of the subjects were homozygous for the 192 bp allele (wild type), 46% were heterozygous and 11% were non-carriers. Significantly lower systolic and diastolic blood pressures were found in non-carrier subjects (difference compared with homozygous subjects: −4.4 (95% confidence interval (CI) −7.8 to −1.1) mmHg and −3.5 (95% CI: −6.9 to −0.1) mm respectively). No significant differences were found for left heart dimensions at the age of 2 years. No association was found when we used a previously proposed alternative classification of the IGF-I gene.

Conclusion

The variant type of the IGF-I promoter region is associated with lower blood pressure but not with left heart dimensions at the age of 2 years. Follow-up studies are needed to examine whether these differences persist in later life.
Amyloidosis induced colonic stricture. The first symptom of myeloma multiplex. A case report
Authors: Annaházi Anita , Németh István , Modok Szabolcs , Szentpáli Károly , Tiszlavicz László , Wittmann Tibor , Czakó László
Published: June 2008

A szisztémás amyloidosis gyakran érinti a gastrointestinalis rendszert fekély vagy polypoid elváltozás formájában, a vastagbelet körkörösen szűkítő folyamat azonban különösen ritka. Amyloidosis előfordulása a λ-könnyűláncot termelő myeloma multiplexes betegek kb. 10%-ában várható, szövettanilag AL típusú. A hematológiai betegség diagnózisa azonban szinte minden esetben megelőzi a gastrointestinalis tünetek jelentkezését.Esetismertetés:Egy 73 éves nőbeteget anémia, hasi fájdalom, haematochesia miatt vizsgáltunk. A kolonoszkópia során körkörös sigmabélstenosis igazolódott, mely neoplasia gyanúját vetette fel. A szűkület megoldására sigmaresectio történt rectosigmoidealis anastomosissal. A resecatum szövettani vizsgálata AA-amyloidosist állapított meg. A kivizsgálás során a subcutan zsírszöveti biopszia szisztémás amyloidosis lehetőségét vetette fel. Az immunelektroforézis emelkedett gamma-globulin-frakciót, ezen belül IgG-λ-monoclonalis komponenst és egy másik λ-típusú könnyűlánckomponenst állapított meg. Ezért Jamshidi-biopszia történt, mely myeloma multiplexet igazolt.Következtetések:Betegünknél a ritka, vastagbelet obstruáló, tumort utánzó bélfali amyloidosis vezetett el a myeloma multiplex diagnózisához. A hematológiai kórkép célzott kezelése mellett ilyen esetben szükséges lehet a körülírt szűkület endoszkópos stentelése vagy a sebészi terápia.
Treatment prospects of lysosomal storage disorders
Authors: Reismann Péter , Tulassay Zsolt
Published: June 2008

A lizoszómák enzimeinek hiánya vagy csökkent működése, illetve az enzimek és szubsztrátjaik transzportzavara okozza a lizoszomális tárolási rendellenességeket. A le nem bontott makromolekulák felhalmozódnak, károsítják a sejteket, ami különböző klinikai tüneteket okozhat. Ma megközelítőleg 40 különböző tárolási betegséget különítünk el. Kezelésükben az elmúlt évtizedekig csak szupportív módszereket alkalmaztunk. Az elmúlt évtizedek kutatási eredményei kiszélesítették a terápiás lehetőségeket. A közlemény bemutatja a lizoszomális tárolási betegségeket, áttekinti a terápiás lehetőségeket jelentő enzimpótló kezelést, a szubsztrátcsökkentő terápiát, a csontvelő-átültetést, és felveti a jövő lehetséges kezelését, az őssejtbeültetést és a génterápiát.
Nanomaterials in the environment: Behavior, fate, bioavailability, and effects
Authors: Klaine Stephen J , Alvarez Pedro J. J , Batley Graeme E , Fernandes Teresa F , Handy Richard D , Lyon Delina Y , Mahendra Shaily , McLaughlin Michael J , Lead Jamie R
Published: June 2008

The recent advances in nanotechnology and the corresponding increase in the use of nanomaterials in products in every sector of society have resulted in uncertainties regarding environmental impacts. The objectives of this review are to introduce the key aspects pertaining to nanomaterials in the environment and to discuss what is known concerning their fate, behavior, disposition, and toxicity, with a particular focus on those that make up manufactured nanomaterials. This review critiques existing nanomaterial research in freshwater, marine, and soil environments. It illustrates the paucity of existing research and demonstrates the need for additional research. Environmental scientists are encouraged to base this research on existing studies on colloidal behavior and toxicology. The need for standard reference and testing materials as well as methodology for suspension preparation and testing is also discussed.
A Global Approach to Asphaltene Deposition Problems
Authors: Izquierdo A. , Rivas O.
Published: June 2008

Asphaltene deposition causes serious problems in production operations, from the reservoir, through production tubing, and in surface facilities. This work presents a systematic approach, preventive and corrective, taken at Intevep S.A to handle asphaltenes deposition problems at the different stages of crude oil production A predictive tool has been developed at Intevep. It is a software based on thermodynamically considerations, SPLASH (Solid Phase fLASH). It requires as input data, PVT and dead oil characterization and delivers the phase diagram of the crude oil. Phase diagrams obtained are shown. If as a resuit of the simulation, asphaltenes deposition is expected, preventive actions are recommended. We have successfully used continuous down whole injection of dispersants. As in the case of surface facilities, dispersants are specifically selected for each crude. Additional production in 1995 was estimated in 900000 barrels. A reservoir simulator has been developed as well. This is an in-house modification of a compositional commercially available simulator. It allows to simulate the behavior of the reservoir under asphaltene precipitation conditions. A simulation example for a reservoir in eastern Venezuela is presented.
Intracerebroventricular Administration of Neuropeptide Y Induces Hepatic Insulin Resistance via Sympathetic Innervation
Authors: van den Hoek Anita M. , van Heijningen Caroline , Schröder-van der Elst Janny P. , Ouwens D. Margriet , Havekes Louis M. , Romijn Johannes A. , Kalsbeek Andries , Pijl Hanno
Published: June 2008

OBJECTIVE—We recently showed that intracerebroventricular infusion of neuropeptide Y (NPY) hampers inhibition of endogenous glucose production (EGP) by insulin in mice. The downstream mechanisms responsible for these effects of NPY remain to be elucidated. Therefore, the aim of this study was to establish whether intracerebroventricular NPY administration modulates the suppressive action of insulin on EGP via hepatic sympathetic or parasympathetic innervation.

RESEARCH DESIGN AND METHODS—The effects of a continuous intracerebroventricular infusion of NPY on glucose turnover were determined in rats during a hyperinsulinemic-euglycemic clamp. Either rats were sham operated, or the liver was sympathetically (hepatic sympathectomy) or parasympathetically (hepatic parasympathectomy) denervated.

RESULTS—Sympathectomy or parasympathectomy did not affect the capacity of insulin to suppress EGP in intracerebroventricular vehicle–infused animals (50 ± 8 vs. 49 ± 6 vs. 55 ± 6%, in hepatic sympathectomy vs. hepatic parasympathectomy vs. sham, respectively). Intracerebroventricular infusion of NPY significantly hampered the suppression of EGP by insulin in sham-denervated animals (29 ± 9 vs. 55 ± 6% for NPY/sham vs. vehicle/sham, respectively, P = 0.038). Selective sympathetic denervation of the liver completely blocked the effect of intracerebroventricular NPY administration on insulin action to suppress EGP (NPY/hepatic sympathectomy, 57 ± 7%), whereas selective parasympathetic denervation had no effect (NPY/hepatic parasympathectomy, 29 ± 7%).

CONCLUSIONS—Intracerebroventricular administration of NPY acutely induces insulin resistance of EGP via activation of sympathetic output to the liver.
Extension of Type 2 Diabetes Genome-Wide Association Scan Results in the Diabetes Prevention Program
Authors: Moore Allan F. , Jablonski Kathleen A. , McAteer Jarred B. , Saxena Richa , Pollin Toni I. , Franks Paul W. , Hanson Robert L. , Shuldiner Alan R. , Knowler William C. , Altshuler David , Florez Jose C. ,   for the Diabetes Prevention Program Research Group
Published: June 2008

OBJECTIVE— Genome-wide association scans (GWASs) have identified novel diabetes-associated genes. We evaluated how these variants impact diabetes incidence, quantitative glycemic traits, and response to preventive interventions in 3,548 subjects at high risk of type 2 diabetes enrolled in the Diabetes Prevention Program (DPP), which examined the effects of lifestyle intervention, metformin, and troglitazone versus placebo.

RESEARCH DESIGN AND METHODS— We genotyped selected single nucleotide polymorphisms (SNPs) in or near diabetes-associated loci, including EXT2, CDKAL1, CDKN2A/B, IGF2BP2, HHEX, LOC387761, and SLC30A8 in DPP participants and performed Cox regression analyses using genotype, intervention, and their interactions as predictors of diabetes incidence. We evaluated their effect on insulin resistance and secretion at 1 year.

RESULTS— None of the selected SNPs were associated with increased diabetes incidence in this population. After adjustments for ethnicity, baseline insulin secretion was lower in subjects with the risk genotype at HHEX rs1111875 (P = 0.01); there were no significant differences in baseline insulin sensitivity. Both at baseline and at 1 year, subjects with the risk genotype at LOC387761 had paradoxically increased insulin secretion; adjustment for self-reported ethnicity abolished these differences. In ethnicity-adjusted analyses, we noted a nominal differential improvement in β-cell function for carriers of the protective genotype at CDKN2A/B after 1 year of troglitazone treatment (P = 0.01) and possibly lifestyle modification (P = 0.05).

CONCLUSIONS— We were unable to replicate the GWAS findings regarding diabetes risk in the DPP. We did observe genotype associations with differences in baseline insulin secretion at the HHEX locus and a possible pharmacogenetic interaction at CDKNA2/B.
Beyond Reference and Designation: On Interactive Implications of the Pronoun I in English
Authors: Hrisonopulo Katherine
Published: June 2008

Beyond Reference and Designation: On Interactive Implications of the Pronoun I in English

Using English-language material the paper aims to elaborate a theoretical model for the study of personal pronouns which could account for those uses of pronouns that go beyond their typical deictic (or referential) function of indicating speech-event participants. The proposed analysis focuses on the following two usage types of the pronoun I: (1) I say, there are lots of places to see there; (2) I tell you, John is the one to rely on. It is argued that despite idiomatic boundedness of the pronoun I in the expressions I say and I tell you the pronoun does contribute to the pragmatic effects of the utterances in (1) and (2), namely, the effects of attention seeking and persuasion respectively. It is assumed that these effects could be attributed to interactive implications of the pronoun I that typically emerge in situations of dialogic discourse. To account for interactive orientedness of the first-person pronoun the paper puts forward two interrelated hypotheses. First, it is supposed that the first-person pronoun functions as a sign which is indexed to four regular contexts: referential context, perceptual context, the context of the speaker's subjective experiences, the context of interaction. Second, it is hypothesized that interactive implications of the pronoun I are introduced into oral discourse due to the interplay of two or more of the postulated contexts. Both hypotheses are further substantiated with reference to examples of oral discourse drawn from English-language fiction.
Developing Citizens: The Impact of Civic Learning Opportunities on Students’ Commitment to Civic Participation
Authors: Kahne Joseph E. , Sporte Susan E.
Published: June 2008

This study of 4,057 students from 52 high schools in Chicago finds that a set of specific kinds of civic learning opportunities fosters notable improvements in students’ commitments to civic participation. The study controls for demographic factors, preexisting civic commitments, and academic test scores. Prior large-scale studies that found limited impact from school-based civic education often did not focus on the content and style of the curriculum and instruction. Discussing civic and political issues with one’s parents, extracurricular activities other than sports, and living in a civically responsive neighborhood also appear to meaningfully support this goal. Other school characteristics appear less influential.
Teacher Effectiveness in First Grade: The Importance of Background Qualifications, Attitudes, and Instructional Practices for Student Learning
Authors: Palardy Gregory J. , Rumberger Russell W.
Published: June 2008

This study uses Early Childhood Longitudinal Study data to investigate the importance of three general aspects of teacher effects—teacher background qualifications, attitudes, and instructional practices—to reading and math achievement gains in first grade. The results indicate that compared with instructional practices, background qualifications have less robust associations with achievement gains. These findings suggest that the No Child Left Behind Act’s “highly qualified teacher” provision, which screens teachers on the basis of their background qualifications, is insufficient for ensuring that classrooms are led by teachers who are effective in raising student achievement. To meet that objective, educational policy needs to be directed toward improving aspects of teaching, such as instructional practices and teacher attitudes.
Accountability Texas-Style: The Progress and Learning of Urban Minority Students in a High-Stakes Testing Context
Authors: Heilig Julian Vasquez , Darling-Hammond Linda
Published: June 2008

This study examines longitudinal student progress and achievement on the elementary, middle, and high school levels in relation to accountability policy incentives in a large urban district in Texas. Using quantitative analyses supplemented by qualitative interviews, the authors found that high-stakes testing policies that rewarded and punished schools based on average student scores created incentives for schools to “game the system” by excluding students from testing and, ultimately, school. In the elementary grades, low-achieving students were disproportionately excluded from taking the high-stakes Texas Assessment of Academic Skills tests, demonstrating gains not reflected on the low-stakes Stanford Achievement Test–Ninth Edition. Student exclusion at the elementary level occurred through special education and language exemptions and missing scores. Furthermore, gaming strategies reduced educational opportunity for African American and Latino high school students. Sharp increases in 9th-grade student retention and disappearance were associated with increases in 10th-grade test scores and related accountability ratings.