bluuebunny/crossref_metadata_2025 huggingface dataset:
Birth outcomes in women who have taken leflunomide during pregnancy
Authors: Chambers Christina D. , Johnson Diana L. , Robinson Luther K. , Braddock Stephen R. , Xu Ronghui , Lopez‐Jimenez Janina , Mirrasoul Nicole , Salas Elizabeth , Luo Yunjun J. , Jin Shelia , Jones Kenneth Lyons ,   Organization of Teratology Information Specialists Collaborative Research Group
Published: January 2010

Objective

In preclinical reproductive studies, leflunomide was found to be embryotoxic and teratogenic. Women treated with leflunomide are advised to avoid pregnancy; those who become pregnant are advised to reduce fetal exposure through a cholestyramine drug elimination procedure. The present study was undertaken to investigate pregnancy outcomes in women who received leflunomide and were treated with cholestyramine during pregnancy.

Methods

Sixty‐four pregnant women with rheumatoid arthritis (RA) who were treated with leflunomide during pregnancy (95.3% of whom received cholestyramine), 108 pregnant women with RA not treated with leflunomide, and 78 healthy pregnant women were enrolled in a prospective cohort study between 1999 and 2009. Information was collected via interview of the mothers, review of medical records, and specialized physical examination of infants.

Results

There were no significant differences in the overall rate of major structural defects in the exposed group (3 of 56 live births [5.4%]) relative to either comparison group (each 4.2%)(P = 0.13). The rate was similar to the 3–4% expected in the general population. There was no specific pattern of major or minor anomalies. Infants in both the leflunomide‐exposed and non–leflunomide‐exposed RA groups were born smaller and earlier relative to infants of healthy mothers; however, after adjustment for confounding factors, there were no significant differences between the leflunomide‐exposed and non–leflunomide‐exposed RA groups.

Conclusion

Although the sample size is small, these data do not support the notion that there is a substantial increased risk of adverse pregnancy outcomes due to leflunomide exposure among women who undergo cholestyramine elimination procedure early in pregnancy. These findings can provide some reassurance to women who inadvertently become pregnant while taking leflunomide and undergo the washout procedure.
Towards the Accurate Calculation of 183W NMR Chemical Shifts in Polyoxometalates: The Relevance of the Structure
Authors: Vilà‐Nadal Laia , Sarasa José Pedro , Rodríguez‐Fortea Antonio , Igual Joan , Kazansky Leonid P. , Poblet Josep M.
Published: January 2010

DFT calculations were carried out to study 183W NMR chemical shifts in the family of the Keggin anions with formula α‐[XW12O40]q− (X=B, Al, Si, P, Ga, Ge, As, Zn), in the β‐ and γ‐[SiW12O40]4− geometric isomers, in the derivative Dawson anion [P2W18O62]6−, and in the most symmetrical Lindqvist [W6O19]2− anion and its derivative [W10O32]4−. In this article, we show that the geometry employed in the calculation of NMR chemical shifts in polyoxotungstates is extremely important if we want to be quantitative. Using very large basis sets of QZ4P quality and taking into account the conductor‐like screening model (COSMO) to account for solvent effects (aqueous and organic solutions), good geometries were found for the polyoxoanions. From these optimal geometries the 183W NMR chemical shifts were computed with the more standard basis sets of TZP quality and including spin–orbit corrections inside the zero‐order regular approximation (ZORA) to describe the relativistic effects of the internal electrons. With this strategy the mean absolute error between experimental and theoretical values was found to be less than 10 ppm, which is similar to the experimental error. We also discuss how the geometry of the polyoxoanion influences on the shielding.
An Air Stable Moisture Resistant Titanium Triflate Complex as a Lewis Acid Catalyst for CC Bond Forming Reactions
Authors: Bull Steven D. , Davidson Matthew G. , Johnson Andrew L. , Mahon Mary F. , Robinson Diane E. J. E.
Published: January 2010

An air and moisture stable C3‐symmetric titanium(IV) triflate, supported by a tripodal amine‐(tris‐phenolate) ligand, has been synthesized and characterized by X‐ray crystallography and shown to be a good Lewis acid catalyst for a range of aza‐Diels–Alder, Diels–Alder, syn aldol, allylation, and alkylation reactions.
Total Synthesis Confirms Laetirobin as a Formal Diels–Alder Adduct
Authors: Simon Oliver , Reux Bastien , La Clair James J. , Lear Martin J.
Published: January 2010

Laetirobin, isolated from a parasitic fungus host–plant relationship, was synthesized in six practical steps with an overall yield of 12 % from commercially available 2,4‐dihydroxyacetophenone. Because the product is a pseudosymmetric tetramer of benzo[b]furans, each step of the synthesis was designed to involve tandem operations. Highlights include: 1) the double Sonogashira reaction of a bis(alkyne), 2) the practical copper(I)‐mediated formation of a bis(benzo[b]furan), and 3) the biomimetic [4+2] dimerization and unexpected cationic [5+2] annulation of gem‐diaryl alkene precursors. Preliminary structure–activity relationship data between the isomeric [4+2] and [5+2] tetramers revealed only the natural product to possess promising anticancer potential. Specifically, laetirobin is capable of blocking tumor cell division (mitosis) and invoking programmed cell death (apoptosis).
Tuned CH Functionalization to Construct Aza‐Podophyllotoxin/Aza‐Conidendrin Derivatives by Means of Domino Cyclization
Authors: Hu Yimin , Qu Yuan , Wu Fenghua , Gui Jinghan , Wei Yun , Hu Qiong , Wang Shaowu
Published: January 2010

An efficient domino cyclization method for the construction of aza‐podophyllotoxin/aza‐conidendrin derivatives has been established. Reactions of different dienes with aryl halides in the presence of a palladium catalytic system produced different kinds of podophyllotoxin derivatives through a highly regioselective CH functionalization. Treatment of dienes with aryl halides that have electron‐withdrawing substituents on the phenyl ring created aza‐podophyllotoxin derivatives by means of the functionalization of the CH bonds ortho to the Chalide bonds of the incoming aryl halides. The reaction of dienes with 1‐iodobenzene or aryl halides that incorporate electron‐donating groups produced aza‐conidendrin derivatives by means of the functionalization of both sp3 CH and sp2 CH bonds. The regioselective CH functionalization for the formation of different pseudo‐podophyllotoxin/‐conidendrin derivatives is proven by analyses of the 1H NMR spectra of the products and selective X‐ray analyses of the structures of the products. Thus, the palladium‐catalyzed domino cyclization of 1,6‐dienes for the preparation of aza‐podophyllotoxin/aza‐conidendrin derivatives can be controlled by selectively controlling the CH functionalization.
Photoassisted Synthesis of Luminescent Mannose–Au Nanodots for the Detection of Thyroglobulin in Serum
Authors: Huang Chih‐Ching , Hung Yu‐Lun , Shiang Yen‐Chun , Lin Tai‐Yuan , Lin Yu‐Shen , Chen Chao‐Tsen , Chang Huan‐Tsung
Published: January 2010

We have employed mannose‐modified gold nanodots (Man–Au NDs) as a luminescence sensor for the detection of the thyroid‐cancer marker thyroglobulin (Tg) in homogeneous solutions. The luminescent Man–Au NDs are prepared through the reaction of 2.9 nm‐diameter gold nanoparticles (Au NPs) with 11‐mercapto‐3,6,9‐trioxaundecyl‐α‐D‐mannopyranoside (Man‐RSH) under the irradiation of a light‐emitting diode (LED). We have found that the irradiation enhances the quantum yield (∼11 %), alters the emission wavelength and lifetimes, and shortens the preparation time. A luminescence assay has been developed for Tg based on the competition between Tg and Man–Au NDs for the interaction with the concanavalin A (Con A). Because luminescence quenching of the Man–Au NDs by Con A is inhibited by Tg selectivity, we have obtained a highly sensitive and selective assay for Tg.
A Method for the Rapid Discovery of Naturally Occurring Products by Proteins Immobilized on Magnetic Beads and Reverse Affinity Chromatography
Authors: Arai Midori A. , Kobatake Eiji , Koyano Takashi , Kowithayakorn Thaworn , Kato Shigeaki , Ishibashi Masami
Published: January 2010

A highly efficient screening method for naturally occurring products that bind to a specific target protein was demonstrated by using hVDR magnetic beads. The native ligand 1α,25(OH)2 VD3 (1) was selectively bound by hVDR magnetic beads when present in a mixture of natural compounds. Furthermore, this method was shown to be applicable to the identification of natural products that interact with a specific protein immobilized on the beads from an extract of a natural resource. Two new natural compounds were isolated by this method. This approach will be helpful for the discovery of novel, naturally occurring products that bind to specific target proteins. This method has the further advantages that it can identify the HPLC peak corresponding to the target compound for isolation, as well as provide important UV, CD, or MS profile information.
Tautomycin’s Interactions with Protein Phosphatase 1
Authors: Sydnes Magne O. , Isobe Minoru
Published: January 2010

It has been a long journey since tautomycin (TTM) was isolated in 1987 and the discovery that it inhibited protein phosphatase 1 (PP1) more strongly than PP2A until finally the cocrystal structure of TTM and PP1 was presented early in 2009. The fact that TTM shows preference to inhibit PP1 over PP2A makes this compound unique among the known PP1 and PP2A inhibitors. A number of groups were involved in work aiming to unravel TTM’s interactions with PP1 and by doing so hoping to disentangle the secrets as to why TTM is a better inhibitor of PP1 than PP2A. This Focus Review looks back at the work conducted with TTM in order to establish its point of interaction with PP1 prior to X‐ray structure. Finally the conclusions before the X‐ray structure are compared with the real situation.
Conformational Polymorph of o‐Aminoanilinium(dibenzo[18]crown‐6) Supramolecules in [Ni(dmit)2]− Salts
Authors: Akutagawa Tomoyuki , Koshinaka Hiroyuki , Ye Qiong , Noro Shin‐ichiro , Kawamata Jun , Yamaki Hiroshi , Nakamura Takayoshi
Published: January 2010

The supramolecular (HOPD+)(DB[18]crown‐6) cation, in which HOPD+ and DB[18]crown‐6 are o‐aminoanilinium and dibenzo[18]crown‐6, respectively, was introduced into [Ni(dmit)2]− salts (dmit2−=2‐thioxo‐1,3‐dithiole‐4,5‐dithiolate). Conformational polymorphs were observed as tetragonal (HOPD+)(DB[18]crown‐6)[Ni(dmit)2]− (1) and monoclinic (HOPD+)(DB[18]crown‐6)[Ni(dmit)2]− (2). The ammonium group of HOPD+ in salts 1 and 2 formed the NH+⋅⋅⋅O hydrogen bonds at the bottom and upper positions of V‐shaped DB[18]crown‐6, respectively, thereby producing a different supramolecular conformation. The [Ni(dmit)2]− anion arrangements in salts 1 and 2 were 41‐helical π stacking and a two‐dimensional layer, respectively, depending on the conformation of the supramolecular cations. The magnetic behavior of salts 1 and 2 obeyed the Curie–Weiss law at room temperature with S=1/2 spin on the [Ni(dmit)2]− anion. However, the g value and line width in the electron resonance spectra of salt 1 showed a magnetic anomaly at 28 K, which was owing to antiferromagnetic ordering in the 41‐helical [Ni(dmit)2]− π stack. Large temperature‐ and frequency‐dependent dielectric responses were observed for salt 2 at temperatures above 200 K, whereas no particular dielectric responses were observed in salt 1. The molecular motion of HOPD+ within the cationic layer of salt 2 contributed to the dielectric response, and this was supported by ab initio calculations showing the potential‐energy curve for pendulum motion and by the large thermal parameters in the X‐ray crystal structure analysis. The fixed (HOPD+)(DB[18]crown‐6) arrangement in the crystal of salt 1 was consistent with the small dielectric response. The steric hindrance of the o‐amino group of HOPD+ in the supramolecular cation structure yielded the conformational polymorph with different dielectric and magnetic properties.
Morphological Stable Spirobifluorene/Oxadiazole Hybrids as Bipolar Host Materials for Efficient Green and Red Electrophosphorescence
Authors: Tao Youtian , Ao Liang , Wang Qiang , Zhong Cheng , Yang Chuluo , Qin Jingui , Ma Dongge
Published: January 2010

A series of 9,9′‐spirobifluorene/oxadiazole hybrids with various linkages between two components, namely SBF‐p‐OXD (1), SBF‐m‐OXD (2), and SBF‐o‐OXD (3) are designed and synthesized through Suzuki cross‐coupling reactions. The incorporation of a rigid and bulky spirobifluorene moiety greatly improves their thermal and morphological stability, with Td (decomposition temperature) and Tg (glass transition temperature) in the ranges of 401–480 °C and 136–210 °C, respectively. 2 and 3 with meta‐ and ortho‐linkage display higher triplet energy and blue‐shifted absorption and emission than their para‐linked analogue 1 owing to the decreasing π‐conjugation between the two components. Their HOMO and LUMO energy levels depend on the linkage modes within the range of 5.57–5.64 eV and 2.33–2.49 eV, respectively. Multilayer deep red electrophosphorescent devices with 1, 2, 3 as hosts were fabricated and their EL efficiencies follow the order of 3 (o)>2 (m)>1 (p), which correlates with their triplet energy and the separation of HOMO and LUMO distributions at molecular orbitals. The maximum external quantum efficiencies of 11.7 % for green and 9.8 % for deep red phosphorescent organic light‐emitting diodes (OLEDs) are achieved by using 2 and 3 as host materials, respectively.
Recent Advances in Multicatalyst Promoted Asymmetric Tandem Reactions
Authors: Zhou Jian
Published: January 2010

Multicatalyst promoted asymmetric tandem reactions have emerged as a powerful strategy to improve the synthetic efficiency. It enables the synthesis of complex molecules with high selectivity from simple starting materials in an almost biomimetic‐like way. The use of multiple catalyst systems can enlarge the substrate and reaction scope for the reaction design, improve the reactivity, and benefit the control of selectivity. In this Focus Review, the current achievement of this promising field is discussed, including the advantages and difficulties of this research, and the strategies applied to address these problems.
Synthesis of Gold Microplates Using Bovine Serum Albumin as a Reductant and a Stabilizer
Authors: Au Leslie , Lim Byungkwon , Colletti Peter , Jun Young‐Shin , Xia Younan
Published: January 2010

Gold microplates were synthesized in aqueous solutions by reducing HAuCl4 with the hydroxyl groups in both serine and threonine of bovine serum albumin (BSA), which is a globular protein in its native state. In this article, we systematically investigated the effects of temperature, pH value, the concentration of BSA, and ionic species on the reduction kinetics and thus the size and morphology of the final product. The optimal experimental conditions for producing uniform Au microplates include the following: an elevated temperature in the range of 55–65 °C, an acidic solution with pH≈3, and the presence of NaCl (0.14 M). We found that if any one of these parameters was deviated from the optimal condition, Au microplates would not be formed in high yields. We also found that the surfaces of the as‐synthesized Au microplates were covered by a dense array of BSA bumps.
Alternatives to Organoboron Reagents in Rhodium‐Catalyzed Conjugate Additions
Authors: Hargrave Jonathan D. , Allen Joseph C. , Frost Christopher G.
Published: January 2010

The rhodium‐catalyzed conjugate addition of organoboron reagents to alkene acceptors has emerged as an important methodology in organic synthesis. The process results in the formation of new carbon–carbon bonds, and in principle, can create new stereocenters at both the α and β carbon atoms of the acceptor. Other organometallics are known to participate in the key transmetalation to rhodium and are becoming more established in stereoselective synthesis (notably arylzinc reagents). This Focus Review will describe recent developments in the use of alternative organometallic donors to organoboron reagents in rhodium‐catalyzed conjugate addition reactions and their growing applications in synthesis.
Merging European and German Standards – Eurocode 7, DIN 1054 and DIN 4020
Authors: Schuppener Bernd , Ruppert Franz‐Reinhard
Published: January 2010

The German version of Eurocode 7 “Geotechnical Design” with its two parts DIN EN 1997‐1 “General Rules” and DIN EN 1997‐2 “Ground Investigation and Testing” will shortly be available. The two parts of this Eurocode compete to some extent with two fundamental German geotechnical standards: DIN 1054:2005‐1 “Ground – Verification of Safety of Earthworks and Foundations” and DIN 4020:2003‐09 “Geotechnical Investigations for Civil Engineering Purposes”.

According to the regulations of the European Union, standards competing with European standards have to be withdrawn after a harmonisation period of two years and a coexistence period of another 3 years. That is why in three to five years DIN 1054 and DIN 4020, in their present form, will have to be replaced by revised versions. The paper is describing the necessary adaptations as far as the content is concerned and how the specific German geotechnical experience will be conserved in the new system of European and German standards…
On the deformation behaviour of strip footings during the construction process of an adjacent diaphragm wall in soft clayey ground
Authors: Schäfer René , Triantafyllidis Theodor
Published: January 2010

The installation process of diaphragm walls in soft clayey soil deposits can produce considerable deformations on the adjacent ground, affecting the serviceability of nearby structures. This article highlights the influence of the stepwise D‐wall construction process on the development of settlements of neighbouring strip footings. For the simulation of the construction process, a three‐dimensional finite element model of a plain diaphragm wall section and an adjacent footing is assumed. The stress‐strain behaviour of the ground is described by an advanced constitutive model, which especially takes into account the rheological properties of the soft clay, like creep, relaxation and a rate‐dependent stiffness. Numerous calculations are performed, considering the impact of the panel geometry and the installation sequence of the diaphragm wall. Furthermore, the loading as well as the bending stiffness of the strip footing is varied. With respect to the serviceability of the footing, recommendations for the D‐wall construction are finally given, aiming at a prevention oriented construction technique.
Calculation of excavation walls with different methods: Girder model, non‐linear subgrade reaction model, finite‐element analysis
Authors: Hettler Achim , Ortiz Susana Vega , Mumme Britta
Published: January 2010

For a single propped excavation wall, different methods of calculation are compared: Girder model with fixed supporting points, non‐linear subgrade reaction and finite‐element‐analysis using hypoplasticity, respectively hypoplasticity with intergranular strain. Main interest of the investigations are the sectional forces, wall displacements and the embedment of the wall foot. The paper closes with recommendations for the use in practice.
The Uelzen I Lock – Hypoplastic finite‐element analysis of cyclic loading
Authors: von Wolffersdorff Peter‐Andreas , Schwab Radu
Published: January 2010

The Uelzen I lock is a very suitable case to analyse the soil‐structure interaction during cyclic loading, because its plate‐rib structure is very flexible, the amplitude of the load cycles during lock operation is high and an extensive geotechnical monitoring system was installed in 1992.

A 3D finite element simulation was used to predict the long‐term behaviour of the lock during cyclic loading. The main interest of the simulation was to choose an adequate constitutive law to simulate the quasi‐static cyclic behaviour of the soil. The adopted hypoplastic constitutive law with intergranular strain is briefly described in the paper. The computed results are compared with the measurements. The results of elastic‐perfect plastic Mohr‐Coulomb and hypoplastic simulations without intergranular strain are presented for comparison. Some interesting aspects are evidenced, such as the ‘stick‐slip’ reduction of the arching effect in the backfill due to cyclic loading.
Effective algorithm for parameter back calculation – Geotechnical applications
Authors: Meier Jörg , Rudolph Sebastian , Schanz Tom
Published: January 2010

When working with numerical models, it is essential to determine model parameters which are as realistic as possible. Optimization techniques are used more and more frequently to solve this task. However, using these methods may lead to very high time costs – in particular, if rather complicated forward calculations are involved. In this paper, we present a class of methods wich allows estimating the solution of this kind of optimization problems, based on relatively few sampling points. We put very weak constraints on the sampling point distribution; hence, they may be taken from previous forward calculations as well as from alternative sources.

Starting from an introduction into the theoretical approach, a strategy for speeding up inverse optimization problems is introduced which is illustrated by an example from geomechanics.
Buckling of slender piles in soft soils
Authors: Vogt Norbert , Vogt Stefan , Kellner Christian
Published: January 2010

Buckling of piles is prevented by the surrounding soil. Therefore, in sufficiently stiff soils, there is no risk of pile buckling with conventional geometry (L/D ratio). National and international design codes require checks of the safety against buckling for slender piles in soils with undrained shear strengths of cu < 15 kPa or cu < 10 kPa, respectively. In practice, the codes imply that buckling failure does not occur at higher undrained shear strengths. However, using simple calculations, this assumption has been proven to be invalid for slender piles such as micropiles. For the reason, buckling tests on 4 m long micropiles were carried out in soft clay. Based on these results, a new concept with supporting documents for calculating buckling loads was derived, which covers all essential aspects observed in the tests. The proposed model accounts for material non‐linearity, as well as second order effects.
Absence of corneal endothelium injury in non‐human primates treated with and without ophthalmologic drugs and exposed to 2.8 GHz pulsed microwaves
Authors: Lu Shin‐Tsu , D'Andrea John , Chalfin Steven , Crane Carrie , Marchello Donald , Garay Robert , Hatcher Donald , Ziriax John
Published: January 2010

Microwave‐induced corneal endothelial damage was reported to have a low threshold (2.6 W/kg), and vasoactive ophthalmologic medications lowered the threshold by a factor of 10–0.26 W/kg. In an attempt to confirm these observations, four adult male Rhesus monkeys (Macaca mulatta) under propofol anesthesia were exposed to pulsed microwaves in the far field of a 2.8 GHz signal (1.43 ± 0.06 µs pulse width, 34 Hz pulse repetition frequency, 13.0 mW/cm2 spatial and temporal average, and 464 W/cm2 spatial and temporal peak (291 W/cm2 square wave equivalent) power densities). Corneal‐specific absorption rate was 5.07 W/kg (0.39 W/kg/mW/cm2). The exposure resulted in a 1.0–1.2 °C increase in eyelid temperature. In Experiment I, exposures were 4 h/day, 3 days/week for 3 weeks (nine exposures and 36 h total). In Experiment II, these subjects were pretreated with 0.5% Timolol maleate and 0.005% Xalatan® followed by 3 or 7 4‐h pulsed microwave exposures. Under ketamine–xylazine anesthesia, a non‐contact specular microscope was used to obtain corneal endothelium images, corneal endothelial cell density, and pachymetry at the center and four peripheral areas of the cornea. Ophthalmologic measurements were done before and 7, 30, 90, and 180 days after exposures. Pulsed microwave exposure did not cause alterations in corneal endothelial cell density and corneal thickness with or without ophthalmologic drugs. Therefore, previously reported changes in the cornea exposed to pulsed microwaves were not confirmed at exposure levels that are more than an order of magnitude higher. Bioelectromagnetics 31:324–333, 2010. Published 2010 Wiley‐Liss, Inc.
Power variations of wireless communication systems
Authors: Andersen J.B. , Mogensen P.E. , Pedersen G.F.
Published: January 2010

The use of wireless digital communication devices like GSM, WCDMA, HSPA, DECT, and WiFi changes the exposure of electromagnetic waves toward the user. Concentrating on the power variations on a slow and fast time scale, these new systems are discussed. Experimental results for both uplink and downlink are included for a sample of systems. The spectrum of the power fluctuations is seen as a convenient and compact way of describing very complex system behavior. The results are of interest for scientific studies of epidemiology and biological effects, and for general electromagnetic compatibility (EMC) aspects. Bioelectromagnetics 31:302–310, 2010. © 2010 Wiley‐Liss, Inc.
Richtungsanalyse von Fasern in Betonen auf Basis der Computer‐Tomographie
Authors: Schnell Jürgen , Schladitz Katja , Schuler Frank
Published: January 2010

Für die Festbetoneigenschaften von Faserbetonen sind die Fasermenge, Faserorientierung und Faserverteilung ausschlaggebend. Dies macht eine Überwachung dieser Parameter notwendig, sei es zur Qualitätssicherung auf der Baustelle oder im Bereich der Forschung zur Weiterentwicklung solcher Betone. Gegenüber bisher angewendeten Methoden zur Untersuchung dieser Einflussgrößen eröffnet die Computer‐Tomographie die Möglichkeit, für Betone mit Fasern und Gelegen aller Art die Faserorientierung und Faserverteilung im gesamten Volumen eines Probekörpers zu betrachten und zu analysieren.

Direction Analysis of Fibres in Concrete on Basis of Computed Tomography

Decisive factors for the improvement of the hardened concrete characteristics of fibre reinforced concrete are the fibre‐volumeratio, fibre‐orientation and fibre‐distribution. The application of fibre reinforced concrete mixtures requires an appropriate control of these characteristics in the context of quality control at the building site as well as in research work done to improve this kind of concretes. Compared to the methods used up to now, the computed tomography offers the possibility to examine and analyze fibre‐orientation and fibre‐distribution in the entire volume of a specimen.
Textilbeton verstärkte Platten unter Brandbelastung
Authors: Ehlig Daniel , Jesse Frank , Curbach Manfred
Published: January 2010

Im Rahmen experimenteller Untersuchungen wurden Stahlbetonplatten hergestellt, mit verschiedenen textilen Bewehrungen verstärkt, durch Belastung bis 125% Gebrauchslast vorgeschädigt und anschließend unter Gebrauchslast mit einer Brandbelastung nach der Einheitstemperaturkurve (ISO‐834, Cellulosic curve) beaufschlagt. Alle Platten hielten der Brandbelastung bei gleichzeitiger Biegebeanspruchung mehr als 60 Minuten stand und zeigten weder Betonabplatzungen noch andere optische Schädigungen auf. Die für dieses überraschend positive Ergebnis verantwortlichen Mechanismen werden diskutiert, sind aber noch nicht vollständig verstanden. Eine Schlüsselrolle spielt dabei vermutlich das gute Rissverhalten von Textilbeton und interne Lastumlagerungen zwischen Textil‐ und Stahlbewehrung.

Textile Reinforced Concrete Strengthened Slabs under Fire Loading

Within an experimental study steel reinforced concrete slabs were produced and strengthened with different types of textile reinforcements. They were than pre‐damaged with 125% service load and subsequently exposed to fire loading (ISO‐834, Cellulosic curve) under simultaneous service load. The tests lasted up to 60 minutes with no specimen failed. The slabs did not show any visual damage nor concrete spalling. We discuss the presumably reasons for that surprisingly positive test result, although mechanisms are not yet fully understood. The excellent crack control of TRC and load redistribution between textile and steel reinforcement as well as load redistribution in the slabs are assumedly key mechanisms that contribute to the excellent fire resistance.
Introducing proteomics in the undergraduate curriculum: A simple 2D gel electrophoresis exercise with serum proteins
Authors: Kim Thomas D. , Craig Paul A.
Published: January 2010

Two‐dimensional gel electrophoresis (2DGE) remains an important tool in the study of biological systems by proteomics. While the use of 2DGE is commonplace in research publications, there are few instructional laboratories that address the use of 2DGE for analyzing complex protein samples. One reason for this lack is the fact that the preparation of samples for 2DGE is a complex and difficult process that can commonly yield gels of poor quality and resolution. In this experiment, we use a serum‐based sample to mitigate many of the sample preparation issues that occur in cell‐based sample preparations and incorporate a protein precipitation method that was developed to address the problem of high‐abundance proteins and dynamic range in serum proteomics research. By focusing on 2DGE apart from many other facets of proteomic experimental design, students have the opportunity to gain fruitful experience in the use of this workhorse proteomics technique. This simplified focus also makes this exercise accessible to biochemistry instructors who are not active in proteomics; the requisite techniques may require some new equipment (i.e. an isoelectric focusing apparatus), but this exercise focuses on using familiar techniques (primarily electrophoresis) to cross the threshold of a new field, proteomics.
Paternity testing in a PBL environment
Authors: Casla Alberto Vicario , Zubiaga Isabel Smith
Published: January 2010

Problem Based Learning (PBL) makes use of real‐life scenarios to stimulate students' prior knowledge and to provide a meaningful context that is also related to the student's future professional work. In this article, Paternity testing is presented using a PBL approach that involves a combination of classroom, laboratory, and out‐of‐class activities: in relation to a fictitious newborn found on the Campus, students design a PCR based protocol to determine their own genotype for two markers. Pooled class genotypes serve to calculate allelic frequencies and to assess Hardy–Weinberg equilibrium. Individual results are also evaluated for possible paternity. The goals of the activity and how each step in the process relates to learning outcomes are presented. Classroom discussions, group discussions, tutorial sessions, wiki sites, laboratory activities, and individual reports sum up the situations, in which the students' process of learning and learning outcomes can be evaluated.
Fetal development of the retrohepatic inferior vena cava and accessory hepatic veins: Re‐evaluation of the Alexander Barry's hypothesis
Authors: Jin Zhe Wu , Cho Baik Hwan , Murakami Gen , Fujimiya Mineko , Kimura Wataru , Yu Hee Chul
Published: January 2010

The retrohepatic inferior vena cava (IVC) is commonly considered to originate from the right vitelline or omphalomesenteric vein. In contrast, Alexander Barry hypothesized that one of the hepatic veins grows to merge with the subcardinal vein and develops into the retrohepatic IVC. We re‐examined fetal development of the retrohepatic IVC and other related veins using serial histological sections of 20 human fetuses between 6 and 16 weeks of gestation. At 6–7 weeks, when a basic configuration of the portal‐hepatic vein systems had just been established, one of hepatic veins (i.e., the posterocaudal vein in the present study) had grown caudally to reach the posterocaudal surface of the liver, and notably, extended into the primitive right adrenal gland (five of the eight early‐staged fetuses). Because the inferior right hepatic vein (IRHV) and retrohepatic IVC appeared at the same developmental stage, it is likely that any peripheral remnants of the posterocaudal vein would continue to function as primary drainage territory for the IRHV. The caudate vein developed rapidly in accordance with marked caudal and leftward extension of Spiegel's lobe at 12–16 weeks. Thin accessory hepatic veins developed later than the caudate vein and IRHV. The present results supported Barry's hypothesis. Clin. Anat. 23:297–303, 2010. © 2010 Wiley‐Liss, Inc.
Effects of Operating Parameters on the Cinnamaldehyde Content of Extracted Essential Oil Using Various Methods
Authors: Baseri H. , Haghighi‐Asl A. , Lotfollahi M. N.
Published: January 2010

Supercritical fluid extraction (SFE) of essential oils from commercial cinnamon bark was compared with essential oils that were obtained by hydrodistillation. Effects of operating parameters (pressure, temperature and extraction time of SFE) on the extraction yield and the composition of the extracted volatile oil were studied. Moreover, in the hydrodistillation process, the effect of the pH of the solvent on the concentration of cinnamaldehyde in the extracted volatile oil was studied. The maximum yield of extract in the SFE process is about 7.8 % at 70 °C and 240 bar. The maximum concentration of cinnamaldehyde in the SFE process was obtained at 70 °C and 160 bar, and the maximum concentration of this component in hydrodistillation was achieved at pH = 4.1.
Chitosan/titanate Nanotube Hybrid Membrane with Low Methanol Crossover for Direct Methanol Fuel Cells
Authors: Geng J. , Jiang Z. , Wang J. , Shi Y. , Yang D. , Xiao L.
Published: January 2010

Titanate nanotubes (TNTs) about 10 nm in diameter and 200–600 nm in length were hydrothermally synthesized, and then incorporated into a chitosan (CS) matrix to fabricate chitosan/titanate nanotube (CS/TNT) hybrid membranes for a direct methanol fuel cell (DMFC). These hybrid membranes were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray powder diffraction (XRD), thermogravimetry (TG), and positron annihilation lifetime spectroscopy (PALS). Moreover, their performances, including mechanical strength, water and methanol uptake, methanol permeability, and proton conductivity were determined. SEM results demonstrated that TNTs dispersed homogeneously in the hybrid membranes. Mechanical strength and TG measurements demonstrated that the mechanical and thermal stability of CS/TNT hybrid membranes were much higher than those of pure chitosan membranes. PALS analysis revealed that the fractional free volume (FFV) of CS/TNT hybrid membranes increased with the incorporation of TNTs and, thus, resulting in the reduction of methanol crossover. In all as‐prepared membranes, the hybrid membrane containing 15 wt % TNTs exhibited the highest mechanical strength of 85.0 MPa, low methanol permeability of 0.497 · 10–6 cm2·s–1, and proton conductivity of 0.0151 S·cm–1, which had the potential for DMFC applications.
A Case Study in the Pre‐Calculation of Henry Coefficients
Authors: Franke R. , Hannebauer B. , Jung S.
Published: January 2010

Gas solubilities belong to the class of property data that form the basis for a large number of technological applications. For example, they represent the property data basis for absorption processes and are important in the design of gas‐liquid reactors. In this paper, we determine Henry coefficients as a measure of gas solubility by means of a series of computational approaches used in industrial practice, and we compare the results to experimentally determined values. Temperature‐varied values for hydrocarbon‐alcohol systems constitute the object of the study. Of the methods employed, PSRK, UNIFAC(Do) and COSMO‐RS display the highest predictive capability.
Synthesis, Structure, and Physico‐optical Properties of Manganate(II)‐Based Ionic Liquids
Authors: Pitula Slawomir , Mudring Anja‐Verena
Published: February 2010

Several ionic liquids (ILs) based on complex manganate(II) anions with chloro, bromo, and bis(trifluoromethanesulfonyl)amido (Tf2N) ligands have been synthesized. As counterions, n‐alkyl‐methylimidazolium (Cnmim) cations of different chain length (alkyl=ethyl (C2), propyl (C3), butyl (C4), hexyl (C6)) were chosen. Except for the 1‐hexyl‐3‐methylimidazolium ILs, all of the prepared compounds could be obtained in a crystalline state at room temperature. However, each of the compounds displayed a strong tendency to form a supercooled liquid. Generally, solidification via a glass transition took place below −40 °C. Consequently, all of these compounds can be regarded as ionic liquids. Depending on the local coordination environment of Mn2+, green (tetrahedrally coordinated Mn2+) or red (octahedrally coordinated Mn2+) luminescence emission from the 4T(G) level is observed.1 The local coordination of the luminescent Mn2+ centre has been unequivocally established by UV/Vis as well as Raman and IR vibrational spectroscopies. Emission decay times measured at room temperature in the solid state (crystalline or powder) were generally a few ms, although, depending on the ligand, values of up to 25 ms were obtained. For the bromo compounds, the luminescence decay times proved to be almost independent of the physical state and the temperature. However, for the chloro‐ and bis(trifluoromethanesulfonyl)amido ILs, the emission decay times were found to be dependent on the temperature even in the solid state, indicating that the measured values are strongly influenced by nuclear motion and the vibration of the atoms. In the liquid state, the luminescence of tetrahedrally coordinated Mn2+ could only be observed when the tetrachloromanganate ILs were diluted with the respective halide ILs. However, for [C3mim][Mn(Tf2N)3], in which Mn2+ is in an octahedral coordination environment, a weak red emission from the pure compound was found even in the liquid state at elevated temperatures.
Understanding the Signatures of Secondary‐Structure Elements in Proteins with Raman Optical Activity Spectroscopy
Authors: Jacob Christoph R. , Luber Sandra , Reiher Markus
Published: January 2010

A prerequisite for the understanding of functional molecules like proteins is the elucidation of their structure under reaction conditions. Chiral vibrational spectroscopy is one option for this purpose, but provides only indirect access to this structural information. By first‐principles calculations, we investigate how Raman optical activity (ROA) signals in proteins are generated and how signatures of specific secondary‐structure elements arise. As a first target we focus on helical motifs and consider polypeptides consisting of twenty alanine residues to represent α‐helical and 310‐helical secondary‐structure elements. Although ROA calculations on such large molecules have not been carried out before, our main goal is the stepwise reconstruction of the ROA signals. By analyzing the calculated ROA spectra in terms of rigorously defined localized vibrations, we investigate in detail how total band intensities and band shapes emerge. We find that the total band intensities can be understood in terms of the reconstructed localized vibrations on individual amino acid residues. Two different basic mechanisms determining the total band intensities can be established, and it is explained how structural changes affect the total band intensities. The band shapes can be rationalized in terms of the coupling between the localized vibrations on different residues, and we show how different band shapes arise as a consequence of different coupling patterns. As a result, it is demonstrated for the chiral variant of Raman spectroscopy how collective vibrations in proteins can be understood in terms of well‐defined localized vibrations. Based on our calculations, we extract characteristic ROA signatures of α helices and of 310‐helices, which our analysis directly relates to differences in secondary structure.
Nocardiopsins: New FKBP12‐Binding Macrolide Polyketides from an Australian Marine‐Derived Actinomycete, Nocardiopsis sp.
Authors: Raju Ritesh , Piggott Andrew M. , Conte Melissa , Tnimov Zakir , Alexandrov Kirill , Capon Robert J.
Published: January 2010

A marine‐derived actinomycete, Nocardiopsis sp. (CMB‐M0232), obtained from a sediment sample collected at a depth of 55 m off the coast of Brisbane, Australia, yielded two new macrolide polyketides. Structures for nocardiopsins A and B were assigned by detailed spectroscopic analysis, degradation and chemical derivatization. A Marfey’s analysis revealed an unexpected acid‐mediated partial racemization of the L‐pipecolic acid incorporated within the nocardiopsins. The scope of this racemization was assessed against a selection of natural and synthetic N‐acyl pipecolic acids. While the nocardiopsins are not antibacterial, antifungal or cytotoxic, they do exhibit low‐micromolar binding to the immunophilin FKBP12, consistent with their structural and biosynthetic relationship to the immunosuppressive agents FK506 and rapamycin. The nocardiopsins represent a new point of entry into what has been a valuable, exclusive and reclusive region of bioactive chemical space—that surrounding the FK506/rapamycin pharmacophore.
ChemInform Abstract: Spin Glass Behavior of Isolated, Geometrically Frustrated Tetrahedra of Iron Atoms in the Intermetallic La21Fe8Sn7C12.
Authors: Benbow Evan M. , Dalal Naresh S. , Latturner Susan E.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Suboxides with Complex Anions: The Suboxoindate Cs9InO4.
Authors: Hoch Constantin , Bender Johannes , Simon Arndt
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Tetrahedral [Tt4]4‐ Zintl Anions Through Solution Chemistry: Syntheses and Crystal Structures of the Ammoniates Rb4Sn4·2NH3, Cs4Sn4·2NH3, and Rb4Pb4·2NH3.
Authors: Wiesler Katharina , Brandl Karoline , Fleischmann Andrea , Korber Nikolaus
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Highly Active Heterogeneous Palladium Catalyst Supported on a Synthetic Adsorbent.
Authors: Monguchi Yasunari , Fujita Yuki , Endo Koichi , Takao Shinobu , Yoshimura Masatoshi , Takagi Yukio , Maegawa Tomohiro , Sajiki Hironao
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: FeCl3‐Catalyzed Reduction of Ketones and Aldehydes to Alkane Compounds.
Authors: Dal Zotto Christophe , Virieux David , Campagne Jean‐Marc
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: N‐Arylation of Nitrogen Heterocycles with 2,4‐Difluoroiodobenzene.
Authors: Jitchati Rukkiat , Batsanov Andrei S. , Bryce Martin R.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Amide Synthesis from Alcohols and Amines by the Extrusion of Dihydrogen.
Authors: Nordstroem Lars Ulrik , Vogt Henning , Madsen Robert
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Catalytic Method for the Preparation of Polysubstituted Cyclopentanes: [3 + 2] Cycloaddition of Vinylidenecyclopropanes with Activated Olefins Catalyzed by Triflic Imide.
Authors: Li Wei , Shi Min
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Novel Simple and Efficient Bromination Protocol for Activated Arenes.
Authors: Tsoukala Anna , Liguori Lucia , Occhipinti Giovanni , Bjoersvik Hans‐Rene
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Pyridinium 1,1′‐Binaphthyl‐2,2′‐disulfonates as Highly Effective Chiral Broensted Acid—Base Combined Salt Catalysts for Enantioselective Mannich‐Type Reaction.
Authors: Hatano Manabu , Maki Toshikatsu , Moriyama Katsuhiko , Arinobe Manabu , Ishihara Kazuaki
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Asymmetric Hydrogenation of Ketones Using Ir(III) Complexes of N‐Alkyl‐N′‐tosyl‐1,2‐ethanediamine Ligands.
Authors: Martins Jose E. D. , Morris David J. , Wills Martin
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Azidosulfonylation of Alkenes, Dienes, and Enynes.
Authors: Mantrand Nathalie , Renaud Philippe
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: 1‐Phosphabarrelene Complexes of Palladium and Their Use in Suzuki—Miyaura Coupling Reactions.
Authors: Blug Matthias , Guibert Clement , Le Goff Xavier‐Frederic , Mezailles Nicolas , Le Floch Pascal
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.