bluuebunny/crossref_metadata_2025 huggingface dataset:
Stereoselective determination of ginsenosides Rg3 and Rh2 epimers in rat plasma by LC‐MS/MS: Application to a pharmacokinetic study
Authors: Bae Soo Hyeon , Zheng Yu Fen , Yoo Young Hyo , Kim Jeom Yong , Kim Sun Ok , Jang Min Jung , Seo Jae Hong , Bae Soo Kyung
Published: April 2013

We developed and validated an accurate and sensitive LC–MS/MS method for the simultaneous quantitation of ginsenoside Rg3 and Rh2 epimers (R‐Rg3, S‐Rg3, R‐Rh2, and S‐Rh2) in rat plasma. Analytes were extracted from 0.1 mL aliquots of rat plasma by liquid–liquid extraction, using 2 mL of ethyl acetate. In this assay, dioscin (500 ng/mL) was used as an internal standard. Chromatographic separation was conducted using an Acclaim RSLC C18 column (150 × 2.1 mm, 2.2 μm) at 40°C, with a gradient mobile phase consisting of 0.1% formic acid in distilled water and in acetonitrile, a flow rate of 0.35 mL/min, and a total run time of 20 min. Detection and quantification were performed using a mass spectrometer in selected reaction‐monitoring mode with negative electrospray ionization at m/z 783.4 → 161.1 for R‐Rg3 and S‐Rg3, m/z 621.3 → 161.1 for R‐Rh2 and S‐Rh2, and m/z 867.2 → 761.5 for the internal standard. For R‐Rg3 and S‐Rg3, the lower limit of quantification was 5 ng/mL, with a linear range up to 500 ng/mL; for R‐Rh2 and S‐Rh2, the lower limit of quantification was 150 ng/mL, with a linear range up to 6000 ng/mL. The coefficient of variation for assay precision was less than 10.5%, with an accuracy of 86.4–112%. No relevant cross‐talk or matrix effect was observed. The method was successfully applied to a pharmacokinetic study after oral administration of 400 mg/kg and 2000 mg/kg of BST204, a fermented ginseng extract, to rats. We found that the S epimers exhibited significantly higher plasma concentrations and area under curve values for both Rg3 and Rh2. This is the first report on the separation and simultaneous quantification of R‐Rg3, S‐Rg3, R‐Rh2, and S‐Rh2 in rat plasma by LC‐MS/MS. The method should be useful in the clinical use of ginseng or its derivatives.
Geographic Information Systems in the Service of Alternative Tourism – Methods with Landscape Evaluation and Target Group Preference Weighting
Authors: Varjú Viktor , Suvák Andrea , Dombi Péter
Published: April 2013

There is a large variety of types of rural areas and many of them are rich in landscape beauty. However, their preserved culture and traditions are revalued in today's rapid transformation of lifestyles. Alternative tourism is thus an emerging potential to economically support these areas, at the same time helps to preserve natural and cultural heritage.

The methods provide sophisticated means to analyse the characteristics and the potential attractiveness of landscape and cultural attractions from the viewpoint of alternative tourism development. Homogenous tourism sub‐regions can be defined, and the most suitable development scenarios can be found to the certain areas. Copyright © 2013 John Wiley & Sons, Ltd.
Sex is not an independent risk factor for survival in differentiated thyroid cancer
Authors: Oyer Sam L. , Smith Valerie A. , Lentsch Eric J.
Published: April 2013

Objectives/Hypothesis

To determine the impact of sex on disease‐specific survival (DSS) in differentiated thyroid cancer.

Study Design

Retrospective analysis of population database.

Methods

Adult patients with papillary thyroid carcinoma (PTC) or follicular thyroid carcinoma (FTC) were identified from the Surveillance, Epidemiology, and End Results Database between 1988 and 2003. Patients were grouped according to tumor type (PTC or FTC), with age, sex, tumor size, extension, and nodal or distant metastases recorded. The Kaplan‐Meier method was used to compare DSS based on sex in each group.

Results

We identified 36,725 patients, of which 77% were female and 23% were male. PTC represented 91.3% of patients and FTC the remaining 8.7%. Males with PTC and FTC were diagnosed at an older age and were significantly more likely to present with advanced‐stage disease. In patients ≥45 years old, DSS was similar in male and female patients; however, in patients <45 years old, DSS was significantly worse in males. When compared by stage, DSS was similar among male and female patients with stage II PTC; however, males with stage I PTC had a minimally reduced DSS. Stage‐stratified analysis revealed no DSS difference between male and female patients with FTC.

Conclusions

Male sex does not portray an independent survival risk in differentiated thyroid cancer when survival is compared by disease stage. Men present at a later age with more advanced disease, which may explain their poorer survival seen in some studies.

Level of Evidence

4. Laryngoscope, 123:2913–2919, 2013
AMPK synergizes with the combined treatment of 1′‐acetoxychavicol acetate and sodium butyrate to upregulate phase II detoxifying enzyme activities
Authors: Yaku Keisuke , Matsui‐Yuasa Isao , Konishi Yotaro , Kojima‐Yuasa Akiko
Published: April 2013

Scope

Phase II enzymes play important roles in detoxifying xenobiotics. We previously reported that both 1’‐acetoxychavicol acetate (ACA) and sodium butyrate individually increased phase II enzyme activities. Here, we determined the combined action of ACA and sodium butyrate on phase II enzyme activities in intestinal epithelial cells (IEC 6).

Methods and results

ACA and sodium butyrate synergistically increased phase II enzyme activities. Protein levels of intranuclear transcription factor NF‐E2–related factor 2 (Nrf2) were increased by ACA or sodium butyrate treatment, but treatment with both did not produce a synergistic effect. Intranuclear p53 protein levels were increased by ACA but decreased by sodium butyrate alone or combined treatment with ACA and sodium butyrate. In contrast, p53 acetylation was promoted by sodium butyrate and the ACA and sodium butyrate combination. Inhibition of AMPK activity decreased phase II enzyme activities that were upregulated by treatment with ACA plus sodium butyrate or other phytochemicals, including kaempferol, quercetin, and epigallocatechin‐3‐gallate. Combined treatment with ACA and sodium butyrate increased phosphorylated AMPK levels.

Conclusion

These results suggest that ACA and sodium butyrate synergistically contribute to xenobiotics metabolism. The combined ACA and sodium butyrate treatment synergistically upregulated phase II enzyme activities through AMPK activation and p53 acetylation.
Benzin aus Ether
Authors: Otto Thomas N. , Zimmermann Michael , Dinjus Eckhard , Ceccarelli Christina
Published: April 2013

Flüssige Kohlenwasserstoffe für den Autotank lassen sich nicht nur aus Rohöl destillieren, sondern auch synthetisieren — aus Methanol zum Beispiel. Auch Dimethylether dient als Ausgangsprodukt. Modifizierte Zeolithe katalysieren die Reaktion.
Tanzelemente
Authors: Schoffers Elke
Published: April 2013

Dass es Chemiker gibt, die gerne tanzen, sollte niemanden wundern. Denn vor dem Klischee vom weltfremden Experimentator ohne Aussicht auf finanziellen Reichtum galt: Chemie ist Licht, Hoffnung und Fortschritt — und das wurde im Ballsaal gefeiert.
Nichteuklidische Geometrie in der Chemie?
Authors: Langhals Heinz
Published: April 2013

Eine groteske DFG‐Begutachtung zu einem chemischen Projekt mit einem Ausflug in die Physik zeigt die Realität und neue Wege zur Lösung stereochemischer Fragen. Der Gutachter weiß mehr.
Spinat macht Skeptiker stark
Authors: Groß Michael
Published: April 2013

Spinat enthält nicht viel mehr Eisen als andere grüne Gemüsesorten. Aber woher kam der Mythos vom außerordentlichen Eisenreichtum des Spinats, mit dem Generationen von Eltern ihre Kinder plagten? Waren ein Kommafehler oder das Trockengewicht des Grünzeugs schuld, und hat Popeye Beihilfe zur Irreführung der Kinder und Eltern geleistet?
Schweinefuttergrün war giftig
Authors: Guggolz Ernst
Published: April 2013

Die freien Radikalen sind wieder da. Und die chemisch wie sprachlich bemerkenswerteren Unfälle. Insgesamt war die Ausbeute im letzten Jahr apriltechnisch nicht ganz so groß; dafür ließ die Qualität etwas nach. Nicht überraschend: der große Anteil von leicht vergänglichen Stilblüten aus dem Internet.
Biologisch basierte Basismoleküle
Authors: Riesmeier Jörg
Published: April 2013

Aus Biomasse hergestellte Bausteine für höherwertige Chemikalien und Produkte gibt es immer häufiger. Bereits heute sind zirka 13 Prozent der in der deutschen chemischen Industrie eingesetzten Rohstoffe biobasiert. Wie wird die Entwicklung weitergehen?
Produktionsanlagen im Wandel
Authors: Bug Thorsten
Published: April 2013

Fallende Anteile der europäischen Chemieindustrie am Weltmarkt bereiten Sorgen. Zunehmende Investitionen in Deutschland signalisieren allerdings eine hohe globale Wettbewerbsfähigkeit. Dabei erlebt die Basischemie überraschenderweise einen Aufschwung.
Recycling lohnt sich
Authors: Hillebrand Thomas
Published: April 2013

Die Ökobilanz für Dosen, die Prepolymere für Polyurethanschaum enthalten, bestätigt den Vorteil einer kompletten Verwertung — sowohl von Dose als auch von Inhalt.
UHPLC‐HRMS‐Experimente planen und auswerten — Beispiel Thyroxin
Authors: Neu Volker , Bielow Chris , Schneider Peter , Braun Ralf , Stuppner Hermann , Reinert Knut , Huber Christian G.
Published: April 2013

Ultrahochleistungs‐Flüssigchromatographie und hochauflösende Massenspektrometrie geben neue und detaillierte Einblicke in die Zusammensetzung synthetischer pharmazeutischer Wirkstoffe. Die Geräte detektieren Spuren von Verunreinigungen und Abbauprodukten, und die Methoden machen Abbaumechanismen sichtbar.
A selective strategy for shakedown analysis of engineering structures
Authors: Simon J.‐W. , Kreimeier M. , Weichert D.
Published: April 2013

Determining the load‐bearing capacity of engineering structures is essential for their design. In the case of varying thermo‐mechanical loading beyond the elastic limit, the statical shakedown analysis constitutes a particularly suitable tool for this. The application of the statical shakedown theorem, however, leads to a nonlinear convex optimization problem, which is typically characterized by large numbers of variables and constraints. In the present work, this optimization problem is solved by a primal–dual interior‐point algorithm, which shows a remarkable performance due to its problem‐tailored formulation. Nevertheless, the solution procedure remains still a demanding task from computational point of view. Thus, the aim of this paper is to tackle the task of solving large‐scale problems by use of a new so‐called selective algorithm. This algorithm detects automatically the plastically most affected zones within the structure, which have the highest influence on the solution. The entire system is then reduced to a substructure consisting of these zones, based upon which a new optimization problem can be set up, which is solved with significantly less effort. Consequently, the running time decreases drastically, as is shown by application to numerical examples from the field of power plant engineering. Copyright © 2013 John Wiley & Sons, Ltd.
Sustaining International Partnerships: The European Master of Science Programme in Occupational Therapy, a Case Study
Authors: Ilott Irene , Kottorp Anders , la Cour Karen , van Nes Fenna , Jonsson Hans , Sadlo Gaynor
Published: April 2013

International partnerships are a mechanism for supporting the academic development of occupational therapy and promoting cultural competence. This case study describes the factors that have helped to sustain a post‐qualifying programme implemented by five higher education institutions in Denmark, the Netherlands, Sweden, Switzerland and the UK since 1999. Data collection methods were documentary analysis and the reflections of a purposive sample of six key informants. Cohort and outcome data, from 193 students from 31 countries who enrolled between 1999 and 2011, are reported. Each cohort comprises students from an average of eight countries to optimize inter‐cultural dialogue. Four factors support sustainability. These are 1) supportive professional European networks; 2) timeliness and alignment with European higher education policy; 3) partnership structures and processes that emphasize joint decision making and accountability; and 4) the stimulus and satisfaction associated with internationalization. The main limitations are considering the OT‐EuroMaster as an intrinsic case study and using opportunistic data collection that undermines the rigor and transferability of the findings. Future opportunities include doctoral networks, transnational research and sharing our curricula design with other Regions to spread the collaborative, capacity building endeavours more widely. Copyright © 2013 John Wiley & Sons, Ltd.
Halo‐isocyanates as ‘transformation’ reagents
Authors: Bamsford Clement H. , Middleton Ian P. , Ai‐Lamee Kadem G. , Paprotny Jerzy
Published: April 2013

The advantages of halo‐isocyanates as ‘transformation’ reagents in the synthesis of block and graft copolymers are elaborated. These compounds permit polymeric blocks of vinyl units to be attached to a wide range of starting materials, natural or synthetic. Two stages are involved—isocyanation and grafting—and both may be carried out homogeneously or heterogeneously. Attention is here focused on poly(ether‐urethanes), e.g. Biomer, dextran and poly(ethylene glycol) to which chains of several water‐soluble polymers have been attached.
Morphologies and properties of polyblends. II: Blends of poly(methyl methacrylate) and a chlorine‐containing polycarbonate; effect of added copolymer
Authors: Eastmond G. C. , Jiang M. , Malinconico M.
Published: April 2013

This paper extends our previous study of the morphology and properties of polyblends of a polycarbonate and poly(methyl methacrylate) to an investigation of the influence of small amounts of added graft copolymer. The results demonstrate that, in spite of the complexity of the molecular species involved, graft copolymers can act as effective surfactants in polymer blends. The dominant effect is to form finer dispersions of one component in the other, with commensurate increases in interfacial area. A preliminary investigation of the influence of molecular parameters in the graft copolymer is reported; in all cases the molecular weight of the poly(methyl methacrylate) in the copolymer was kept constant and greater than that of the homopolymer whereas the molecular weight of the polycarbonate was varied. Finer dispersions and greater modifications to the relaxation behaviour were found as the molecular weights of the polycarbonate blocks in the copolymer increased and became comparable with the molecular weight of the homopolymer, and as the copolymer content increased.
Electron spin resonance studies of spin‐labelled polymers. 19. Spin‐labelled poly(vinyl acetate) plasticised with dibutyl phthalate
Authors: Cameron G. Gordon , Clark Peter W. , Bullock Anthony T.
Published: April 2013

E.s.r. spectra of spin‐labelled poly(vinyl acetate) plasticised to varying extents with dibutyl phthalate have been analysed to yield the temperature, T50G, at which the separation of the extrema is 50 G. As in the case of spin‐probed, plasticised poly(vinyl acetate), the reciprocal of T50G shows a linear dependence on the weight fraction of polymer. This observation supports the view that in the region of T50G the label responds to the glass‐to‐rubber relaxation. At temperatures immediately below T50G the low‐field peak in the spectrum is split, indicating that motion of the label occurs with a distribution of correlation times.
Use of poly(styrene‐divinylbenzene) packing materials and tetrahydrofuran for the g.p.c. analysis of cellulose derivatives
Authors: Lloyd Linda L. , White Charles A. , Brookes Alan P. , Kennedy John F. , Warner Frank P.
Published: April 2013

The g.p.c. analysis of nitrate and tricarbanilate derivatives of cellulose is described for the determination of molecular weight distribution. The method uses macroreticular poly(styrene‐divinylbenzene) packing materials with tetrahydrofuran as eluent. The full molecular weight distribution analysis with a three‐column system takes less than 30 min, making the method additionally suitable for the monitoring of industrial nitration processes. A simpler two‐column system is also described which is suitable for the analysis of lower molecular weight materials with improved resolution.
Lithiation, mercuriation, and thalliation of poly(N‐vinylcarbazole): Chemical transformations of the products
Authors: Al‐Kadhumi Ahmed A. H. A. , Hodge Philip , Thorpe F. Gordon
Published: April 2013

N‐Vinylcarbazole was homopolymerised or was copolymerised with divinylbenzene (2% and 4%) using AIBN as initiator. The linear homopolymer was shown not to undergo direct lithiation using n‐butyllithium, but lithiation was achieved using n‐butyllithium and brominated linear poly(N‐vinylcarbazole). The polymers reacted smoothly with mercury (II) acetate or trifluoroacetate in THF or dichloromethane to give mercuriated polymers with high degrees of substitution (approx. 80%); with thallium (III) trifluoroacetate in dichloromethane a thalliated polymer was formed, but with a lower degree of substitution (approx. 20%). The mercuriated and thalliated polymers reacted with iodine (or potassium iodide) to give polymers containing an iodo‐substituent. All the metallated polymers reacted with borane to give polymer‐supported organoboranes which, on treatment with water or alkaline hydrogen peroxide, gave polymers containing boronic acid residues or phenolic residues, respectively. The lithio‐substituent in the linear polymer was converted into chloromercury and carboxylic acid groups.
Radical copolymerisation of maleic anhydride with trans‐stilbene
Authors: Ebdon John R. , Hunt Barry J. , Hussein Shamima
Published: April 2013

Radical copolymerisations of maleic anhydride and trarcs‐stilbene have been carried out in methyl ethyl ketone at 60°C using 2,2′‐azo‐bis‐isobutyronitrile as initiator. The copolymers formed at all feeds are slightly rich in maleic anhydride units but are heterogeneous with regard to both composition and molecular weight distribution. It is concluded that this effect is probably produced by phase separation during the copolymerisation and that any interpretation of copolymerisation rates or copolymer compositions in terms of mechanism is not straightforward.
Poly(n‐butyl α‐cyanoacrylate): A highly sensitive and high contrast resist for electron‐beam and X‐ray lithography
Authors: Eranian Armand , Datamanti Evelyne , Dubois Jean‐Claude , Serre Brigitte , Schué Francois , Montginoul Claude , Giral Louis
Published: April 2013

High molecular weight poly(n‐butyl α‐cyanoacrylate) has been obtained by zwitterionic polymerization. This polymer exhibits sensitivity to an electron beam (20 keV) about 25 times higher than that of PMMA, with a contrast of 3, and a sensitivity to X‐rays (λ = 13−34 Å) about 15 times higher than that of PMMA, with a contrast of 2 3.
Block polymerisation by interfacial coupling of immiscible polymers bearing mutually reactive end‐groups: Interfacial activity of ω‐functionalised polymers
Authors: Paulus Gerard , Jérôme Robert , Teyssié Philippe
Published: April 2013

The coupling of polymers bearing mutually reactive groups is generally prevented by the low concentration of end‐groups and the immiscibility of the polymers. This can be overcome by an interfacial technique concentrating the reactive groups in the interfacial region. This paper focuses on the effect that an end‐group has on the behaviour of a polymer of opposite philicity at a water‐toluene interface. Measurements of the reduction in interfacial tension promoted by poly(ethylene oxide) (PEO) end‐capped by a hydrophobic C10H18 group, and polystyrene (PS) terminated by an ammonium bromide group shed light on the role played by the end‐group in the polymer adsorption. Values of the equilibrium interfacial tension support the conclusion that the adsorption of the hydrophilic polymer (PEO) is largely independent of the C10H18 end‐group whereas the ammonium bromide effectively drives PS to the interfacial region.
Langmuir—Biodgett supermolecular assemblies
Authors: Barraud Andre
Published: April 2013

Molecular electronics and biomimetic chemistry are two promising fields of research which involve micro‐machineries at a molecular level. Such molecular assemblies have to be designed for a specific function and to exhibit selective properties. The Langmuir‐BIodgett (L.B.) method is the simplest and the best suited method to build up molecular assemblies tailored for a specific purpose.

Two examples of molecular assemblies are presented to illustrate the high versatility of this supermolecular engineering: the dioxygen trap, based on alternate L.B. layers, which exhibits biomimetic chemical properties; and lamellar conductors, which make extensive use of semi‐amphiphilic compounds and chemical film manipulations and are tailored for electronic properties.

The advantages of combining solid state chemistry and semi‐amphiphilic compounds are analysed and emphasised.
Cross‐linkable polyester imides
Authors: Serna Felipe J. , de Abajo Javier , de la Campa José G.
Published: April 2013

Aromatic polyesters containing imide pendant groups have been prepared from diphenols and 5‐imidoisophthaloyl chlorides by the interfacial polycondensation method. Linear polyesters without substituents have also been synthesized by the same method for comparative purposes.

The presence of side imide groups enhances the solubility of aromatic polyesters in organic solvents, and the thermal properties are greatly affected, with increases in the glass transition temperatures of up to 60°C, while the thermal resistance (t.g.a.) seems not to be so greatly affected.

When the imide pendant groups are unsaturated, as derived from maleimide, nadimide and tetrahydrophthalimide, the polyesters can be converted into crosslinked materials by means of the appropriate thermal treatment, either as a polymeric powder or as films. Properties such as solubility, thermal resistance and mechanical strength were investigated before and after the cross‐linking reaction.
Solution properties of polyelectrolytes. I. Exclusion chromatography of sodium polystyrene sulphonate in salt‐free water as eluent
Authors: Abad Concepción , Braco Lorenzo , Soria Vicente , García Rosa , Campos Agustín
Published: April 2013

The effect of concentration of sodium polystyrene sulphonate on the elution volume in exclusion chromatography has been investigated using salt‐free water as eluent. A non‐linear increase in the elution volume has been observed with increasing injected sample concentration. Concentration‐dependent calibrations have been obtained which approach the universal calibration for uncharged polymers (dextrans) as polyelectrolyte concentration increases. The separation mechanisms are interpreted in terms of electrostatic and hydrodynamic interactions. A semi‐empirical model is proposed to predict concentration effects of linear polyions in exclusion chromatography and good agreement has been found between experimental and calculated elution volumes.
Behaviour of composites used in the confinement of nuclear wastes. 3. Diffusion of ions through epoxide networks
Authors: Nicaise Elisabeth , Gandini Alessandro , Cheradame Hervé
Published: April 2013

The diffusion of cesium and chloride ions through epoxide membranes was studied under a variety of conditions including self‐diffusion, the presence of other salts in the aqueous solution, an excess of either reagent used in the manufacture of the membrane, the addition of various fillers in the epoxide network and two temperatures. At 23°C, the diffusion coefficient D was (2–6) × 10‐13cm2s−1 for most systems, except when the epoxide was prepared with an excess of the dioxirane component or when untreated glass beads were added to the network. In the latter instance D increased and most notably with glass beads. On the contrary, addition of sand to the epoxide resulted in a more effective barrier against diffusion as shown by a decrease in D. It is concluded that most of these materials should be suitable for the confinement of low and medium activity nuclear wastes.
Photoluminescence and Raman spectroscopy of Cd(S,Se) under hydrostatic pressure
Authors: Sander Thomas , Rinn Markus S. , Klar Peter J.
Published: April 2013

A series of Cd(S,Se) crystals grown by a sublimation method ranging from pure CdS to CdSe were investigated by photoluminescence (PL) and Raman spectroscopy under hydrostatic pressure. The ternary alloy Cd(S,Se) crystallizes in a direct bandgap wurtzite structure at ambient pressure. It undergoes a phase transition to an indirect bandgap rocksalt structure between a pressure of 2 and 3.5 GPa. According to group theory the wurtzite structure possesses four Raman modes whereas the rocksalt structure does not exhibit any active first order Raman modes. Upon release of pressure the Raman signals are recovered whereas the PL signals do not reappear. This may indicate that small domains with rocksalt structure still exist after cycling through the phase transition and thus lead to a nonradiative recombination. The pressure dependence of the longitudinal optical phonons of the ternary alloy were estimated. The pressure slopes tend to increase with the selenium concentration in the samples. This effect can be explained by changing of the bulk modulus from small for CdSe to large for CdS. Furthermore, Grüneisen parameters have been calculated for Cd(S,Se), assuming a linear relationship between the bulk moduli of the pure materials CdS and CdSe.
Formation of the defect halo of swift heavy ion tracks in LiF due to spatial redistribution of valence holes
Authors: Medvedev N. A. , Schwartz K. , Trautmann C. , Volkov A. E.
Published: April 2013

The fundamental effect of the relaxation kinetics of the ensemble of generated valence holes on structure transformations in swift heavy ions tracks in alkali halides is demonstrated. The parameters of the spatial distributions of F‐color centers formed in the nanometric vicinities of the trajectories of different ions (from C to U) decelerated in LiF in the electronic stopping regime were extracted from the in situ spectroscopy experiments. Formation of these defects results from self‐trapping of valence holes appearing during material ionizations followed by creation and decay of self‐trapped excitons. The Monte‐Carlo model is applied in order to determine the initial radial distributions of valence holes in tracks of different ions. The detected large difference between the hole and defect distributions indicates fast and long‐range diffusion of valence holes from the ion trajectory before their self‐trapping. The averaged diffusion coefficient (Dh) of hot holes at the subpicosecond time scale after the projectile passage as well as the conversion efficiencies of valence holes into color centers (β) in relaxing tracks of different ions are estimated (Dh = 0.016–1.4 cm2 s−1, β = 0.01–0.04).
In Vitro Inhibition of the Transcription Factor NF‐κB and Cyclooxygenase by Bamboo Extracts
Authors: Van Hoyweghen Laura , De Bosscher Karolien , Haegeman Guy , Deforce Dieter , Heyerick Arne
Published: April 2013

Several bamboo species have been used in traditional medicine for the treatment of inflammatory conditions. The present study evaluates the in vitro anti‐inflammatory properties of the traditionally used bamboo species Phyllostachys nigra (Lodd.) Munro and Sasa veitchii (Carr.) Rehder to explore their future research opportunities and therapeutic potential as anti‐inflammatory agents. The extracts were evaluated for their potential inhibitory activity at the level of NF‐κB‐induced gene expression and suppression of cyclooxygenase (COX)‐1 and COX‐2 enzyme activities, representative pharmacological targets for the anti‐inflammatory action of glucocorticoids and non‐steroidal anti‐inflammatory drugs, respectively. The activity of P. nigra (Lodd.) Munro and S. veitchii (Carr.) Rehder was compared with bamboo species without traditional anti‐inflammatory indications. High‐performance liquid chromatography with diode‐array detection and liquid chromatography–tandem mass spectrometry analyses were performed to phytochemically characterize the extracts. P. nigra (Lodd.) Munro leaf extract potently inhibited NF‐κB‐induced gene expression, while S. veitchii (Carr.) Rehder leaf extract exerted a selective COX‐2 inhibition. The crude extracts consistently showed a more potent bioactivity than the solid phase extraction fractions. P. nigra (Lodd.) Munro and S. veitchii (Carr.) Rehder both exert anti‐inflammatory properties, but act via a different molecular mechanism. Copyright © 2013 John Wiley & Sons, Ltd.
The apparent paradox of maternal seropositivity as a risk factor for congenital cytomegalovirus infection: a population‐based prediction model
Authors: de Vries Jutte J. C. , van Zwet Erik W. , Dekker Friedo W. , Kroes Aloys C. M. , Verkerk Paul H. , Vossen Ann C. T. M.
Published: April 2013

Because maternal seropositivity for CMV is associated with substantial protection against congenital CMV infection, prevention measures have focused mainly on seronegative pregnant women for decades. However, population‐wide insight in the contribution of nonprimary infection (reactivation and/or re‐infection with a different strain) on the most common sequela, hearing loss, is missing.

A population‐based prediction model was developed to estimate the proportion of congenital CMV‐related hearing loss resulting from nonprimary maternal infection. Incorporated was a meta‐analysis of the risk of hearing loss, calculating pooled proportions of children with hearing loss after nonprimary and primary infection. Subsequently, the model was applied for worldwide present population seroprevalences (range 30–95%).

It was estimated that, for all population seroprevalences, nonprimary maternal infections are responsible for the majority of congenital CMV infections. This proportion increased with seroprevalence, ranging from 57% (95%CI 24–85%) to 96% (95% CI 88–99%) for seroprevalences of 30% to 95%. Our meta‐analysis (six reports) showed that the risk of hearing loss after nonprimary infection was 11% (28/253 children, 95% CI 7–15%) versus 13% (50/385 children, 95% CI 10–16%) after primary infection. Incorporating this risk into our model, we estimated that nonprimary infections also accounted for the majority of CMV‐related hearing loss. This proportion ranged from 53% (95% CI 13–86%) to 95% (95% CI 62–99%) for seroprevalences of 30% to 95%.

Our data underline the worldwide contribution of nonprimary infections in causing CMV‐related hearing loss. These results imply that prevention research such as vaccine and hygiene studies should not only be directed at seronegative but also seropositive pregnant women. Copyright © 2013 John Wiley & Sons, Ltd.
Interaction between ganglioside GM1 and diosgenin in langmuir monolayers at the air/water interface
Authors: Hao Changchun , Zhang Lei , Sun Runguang , Yang Jing , He Guangxiao
Published: April 2013

The interaction between ganglioside GM1 (GM1) and diosgenin (Dios) in mixed monolayers was investigated using surface pressure measurements and atomic force microscopy (AFM). The miscibility and stability of the mixed monolayer was evaluated both in a qualitative and quantitative way in terms of the excess mean molecular area (ΔAex), excess Gibbs energy (ΔGex). The ΔAex of mixed GM1/Dios monolayer was found to have positive deviations from ideality at low Dios mole fractions (XDios = 0.2). Above XDios = 0.2, there was a marked negative deviation from ideal mixing, indicating attractive interaction between GM1 and Dios. According to the values of excess Gibbs energy of mixing monolayers, the more stable monolayers assayed was: XDios = 0.6. The compressibility coefficient was assessed at various surface pressures. The monolayer of Dios was more elasticity or rigid than GM1. The AFM images for the mixed monolayers at 30 mN/m indicated there was obvious phase separation in the mixed monolayers. These findings will provide useful information for understanding the interaction between drug and lipids. SCANNING 36:218–223, 2014. © 2013 Wiley Periodicals, Inc.
Entwicklung von verklebten Holz‐Glaskonstruktionen, Bemessung und Anwendung
Authors: Hochhauser Werner , Winter Wolfgang , Fadai Alireza
Published: April 2013

Lastabtragende Verklebungen von Glas auf Metall haben sich beim Structural Sealant Glazing (SSG) z.B. im Fahrzeugbau bewährt. Das Bauwesen ist generell gegenüber tragenden Verklebungen skeptisch, hauptsächlich wegen des Langzeitverhaltens und wegen der Zwängungsspannungen, die bei Materialien mit unterschiedlichen Wärmedehnungen auftreten. Die Anwendungsregeln der ETAG 002 umfassen dazuhin keine Holzwerkstoffe, obwohl sich diese wegen der ähnlichen Wärmedehnungen von Glas und Holz gut eignen würden und im Fensterbau und im konstruktiven Holzbau genügend Erfahrungen mit tragenden Verklebungen vorliegen. In den letzten Jahren wurden Koppelrahmen aus Holzwerkstoffen entwickelt und getestet und es wurde versucht an die ETAG 002 angelehnte Qualitätskriterien und Bemessungsverfahren zu entwickeln. Diese werden im Überblick beschrieben und es wird kurz auf Fragen der Nachhaltigkeit eingegangen

Development of load bearing timber‐glass composites. Design and application. Structural sealant glazing is largely used in the automobile industry. The building sector is more reluctant mainly because of the long term behaviour and the stresses due to different thermic elongations of glass and metal profiles. Materials with comparable thermic elongations to glass as wood based profiles are not already included in the relevant technical guideline ETAG 002 but there exist considerable bonding experiences in the field of windows and structural applications. In the last years different types of wood based coupling frames had been developed and tested and quality criteria’s and design rules based on the ETAG 002 had been proposed. They are presented in an overview and aspects of sustainability are discussed.
Palacio de Comunicaciones ‐ frei geformtes Glasdach für das neue Rathaus in Madrid
Authors: Burkhardt Uwe , Schlaich Mike
Published: April 2013

Das Rathaus von Madrid ist 2011 endgültig in das aufwändig sanierte Gebäude der ehemaligen Hauptpost, den sogenannten “Palacio de Comunicaciones“, umgezogen. Zu den Umbaumaßnahmen gehörte die vollständige Überdachung des ca. 3000 m2 großen Innenhofs mit einem leichten Glasdach. Die Überdachung wurde als einlagige, doppelt gekrümmte Stabgitterschale mit einer Hauptspannweite von etwa 45 m ausgeführt, was sie zu einer der weitgespanntesten ihrer Art macht. Die einzelnen Stäbe des Dreiecksrasters wurden miteinander verschraubt. Nur durch moderne CNC Fertigung konnten die hohen Anforderungen an die Genauigkeit erreicht werden, die für eine so schlanke Stabgitterschale nötig sind.

Palacio de Comunicaciones ‐ a glass roof for the new town hall of Madrid. The city of Madrid moved its town hall into the completely renovated “Palacio de Comunicaciones” in 2011. A part of this renovation was the covering of the courtyard with a lightweight glass roof to improve its usability. The structure is a single layer grid shell with a surface area of about 3000 m2 and a main span of approx. 45 m which makes it to one of the widest spanning single layer glass grid shells. The bars that form the triangular grid shell are connected by bolted nodes. Two bolt layers assure sufficient bending resistance and lead to speedy erection without the need for prestressing. State‐of‐the‐art CNC techniques for preparing the nodes and bars allowed to achieve the precision needed for such a slender single‐layer grid shell.
Effects of repetitive transcranial magnetic stimulation and transcranial direct current stimulation on posterior alpha wave
Authors: Puanhvuan Dilok , Nojima Kazuhisa , Wongsawat Yodchanan , Iramina Keiji
Published: April 2013

Because of the unclear conclusion of the repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) effects on the posterior electroencephalogram (EEG) alpha wave, this study is aimed at investigating these unclear effects. Transcranial stimulation effects are observed by analyzing a measured EEG at the occipital area between prestimulation and the poststimulation. The EEG alpha power and alpha coherence are calculated and analyzed in terms of the ratio between eyes closed and eyes open periods. The results reveal that alpha power ratio at the individual alpha frequency (IAF) significantly increases after the 1‐Hz rTMS and cathodal tDCS and slightly decreases after the anodal tDCS compared to the control and the sham conditions. The results also show that there is a significant difference between the inhibited and excited conditions. Similarities are observed in the patterns of the alpha coherence ratio and alpha power changes. The alpha coherence increases in the rTMS and cathodal tDCS conditions, and decreases in the anodal tDCS condition but these effects occur only when comparing across the hemispheres (O1–O2 and P3–P4). It can be summarized that the EEG alpha wave can be influenced by the transcranial stimulations. The rTMS and cathodal tDCS seem to facilitate the alpha activity and the anodal tDCS inhibits it. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Narratives of Participation, Identity, and Positionality: Two Cases of Saudi Learners of English in the United States
Authors: Giroir Shannon
Published: April 2013

This article reports a study that investigated how two Saudi Arabian men negotiated their positionality vis‐à‐vis a host community in the United States and how they engaged in different discursive practices in order to achieve fuller participation in the various worlds that became important to them. The study takes data from a larger research project that looked at the narrated experiences of nine adult learners enrolled in an intensive English program in the United States. Data were collected over a 6‐month period using ethnographic data collection tools such as classroom observations, individual interviews, and student‐designed second language (L2) photo narratives. The article focuses on the processes by which two language learners of a particularly politicized and racialized cultural group (Muslims of Arab descent) were able to renegotiate their peripherality through their ongoing interactions as “novices” in new L2 “expert” communities (Lave & Wenger, 1991). Although the two cases diverge in critical ways, the findings show not only how post‐9/11 discourses served as powerfully marginalizing structures, but also how the learners actively managed those structures in their bids for fuller participation in L2 communities.
How Do Wii Know: Anecdotal Records Go Digital
Authors: Bates C.C.
Published: April 2013

Anecdotal records have long been used as a means of formative assessment. This article explores how traditional anecdotal records can be enhanced with digital technology. Using a portable device and one of many available note‐taking applications, teachers have the opportunity to create a richer picture of the student. Highlighted in this Teaching Tip is information on how to take digital notes, how to organize them to assist in making instructional decisions, and ways to use the app's embedded media options to document student learning.
Using maintenance options to maximize the benefits of prognostics for wind farms
Authors: Haddad G. , Sandborn P. A. , Pecht M. G.
Published: April 2013

Many engineering systems incorporate prognostics and health management (PHM), which consists of technologies and methods to assess the reliability of a product in its actual life‐cycle conditions to determine the advent of failure and mitigate system risks. Wind turbines are among the systems that incorporate PHM to reduce life‐cycle costs and increase availability. Although cost–benefit models that quantify the value of implementing prognostics within systems exist for wind energy systems, they do not specifically quantify the value of decisions after a prognostic indication. This paper introduces maintenance options as a means to quantify the value of decisions after a prognostic indication. A case study on a US land‐based wind farm is discussed. An analysis of wind turbine maintenance data is presented, and the maintenance options methodology is then demonstrated to establish the value of the wait‐to‐maintain option. The value of waiting after a prognostic indication is determined using a model that quantifies the benefit that results from a PHM implementation that allows the decision maker to delay maintenance actions, thereby using the remaining life of the system components rather than throwing it away. Copyright © 2013 John Wiley & Sons, Ltd.
Wind gust detection and load mitigation using artificial neural networks assisted control
Authors: Carcangiu C.E. , Pujana‐Arrese A. , Mendizabal A. , Pineda I. , Landaluze J.
Published: April 2013

The design of a wind turbine implies the simulation of definite conditions as specified in the standards. Among those operational conditions, rare events such as extreme gusts or external faults are included, which may cause high structural loads. Such extreme design load cases usually drive the design of some of the main components of the wind turbine: tower, blades and mainframe. Two different strategies are hence presented to mitigate the loads, deriving from extreme load cases, on the basis of the detection of wind gusts by means of ad hoc synthesized artificial neural networks. This tool is embedded into the main control algorithm and allows it to detect the gust in advance, to anticipate the control reaction, and by doing so reducing extreme loads. One of the strategies performs a controlled stop when wind gust is detected. The other rides through wind gusts without stopping, i.e., without affecting the wind turbine normal operation. Aeroelastic simulations of the Alstom Wind's wind turbines using these techniques have shown significant reductions in the extreme loads for all standard IEC 61400‐1, edition 2 DLC 1.6 cases. In particular, the overall ultimate loads are largely reduced for blade root and tower base bending moments, with a direct impact on the structural design of those components. Copyright © 2013 John Wiley & Sons, Ltd.
Characterization of fractured reservoirs using tracer and flow‐rate data
Authors: Juliusson Egill , Horne Roland N.
Published: April 2013

Key Points

Efficient method to characterize fractured reservoirs

Estimation and prediction of tracer transport at variable flow‐rates

Novel inversion methodology for tracer transport data
An accurate method for transient particle tracking
Authors: Maier Uli , Bürger Claudius M.
Published: April 2013

Key Points

we extend finite difference particle tracking to fully transient

using an exact analytical expresssion on rectangular grid

full reversal of flow direction can be handled
On holographic thermalization and gravitational collapse of tachyonic scalar fields
Authors: Wu Bin
Published: April 2013

Abstract

In this paper we study the thermalization of a spatially homogeneous system in a strongly coupled CFT. The non-equilibrium initial state is created by switching on a relevant perturbation in the CFT vacuum during Δt ≳ t ≳ − Δt. Via AdS/CFT, the thermalization process corresponds to the gravitational collapse of a tachyonic scalar field (m
2 = −3) in the Poincare patch of AdS
5. In the limit
$ \varDelta t<\frac{0.02 }{T} $
, the thermalization time t

T
is found to be quantitatively the same as that of a non-equilibrium state created by a marginal perturbation discussed in ref. [5]. In the case
$ \varDelta t\gtrsim \frac{1}{T} $
we also obtain double- collapse solutions but with a non-equilibrium intermediate state at t = 0. In all the cases our results show that the system thermalizes in a typical time
$ {t_T}\simeq \frac{O(1) }{T} $
. Besides, a conserved energy-moment current in the bulk is found, which helps understand the qualitative difference of the collapse process in the Poincare patch from that in global AdS [10, 11].
Severe Postoperative Complications Adversely Affect Long‐Term Survival After R1 Resection for Pancreatic Head Adenocarcinoma
Authors: Petermann David , Demartines Nicolas , Schäfer Markus
Published: April 2013

Background

Survival after pancreatic head adenocarcinoma surgery is determined by tumor characteristics, resection margins, and adjuvant chemotherapy. Few studies have analyzed the long‐term impact of postoperative morbidity. The aim of the present study was to assess the impact of postoperative complications on long‐term survival after pancreaticoduodenectomy for cancer.

Methods

Of 294 consecutive pancreatectomies performed between January 2000 and July 2011, a total of 101 pancreatic head resections for pancreatic ductal adenocarcinoma were retrospectively analyzed. Postoperative complications were classified on a five‐grade validated scale and were correlated with long‐term survival. Grade IIIb to IVb complications were defined as severe.

Results

Postoperative mortality and morbidity were 5 and 57 %, respectively. Severe postoperative complications occurred in 16 patients (16 %). Median overall survival was 1.4 years. Significant prognostic factors of survival were the N‐stage of the tumor (median survival 3.4 years for N0 vs. 1.3 years for N1, p = 0.018) and R status of the resection (median survival 1.6 years for R0 vs. 1.2 years for R1, p = 0.038). Median survival after severe postoperative complications was decreased from 1.9 to 1.2 years (p = 0.06). Median survival for N0 or N1 tumor or after R0 resection was not influenced by the occurrence and severity of complications, but patients with a R1 resection and severe complications showed a worsened median survival of 0.6 vs. 2.0 years without severe complications (p = 0.0005).

Conclusions

Postoperative severe morbidity per se had no impact on long‐term survival except in patients with R1 tumor resection. These results suggest that severe complications after R1 resection predict poor outcome.
Characterizing the communication in the Amazon rainforest: towards a realistic simulation
Authors: Ribas Afonso D. , Carvalho Antonio R. , Figueiredo Carlos M. S. , Nakamura Eduardo F.
Published: April 2013

Many literature papers evaluate solutions in wireless sensor networks by simulation experiments. However, little attention is given to the adequacy of the simulator propagation models to the environment in which such solutions are employed. This can lead to imprecise or inconsistent results in relation to the real world. This paper presents a methodology for adjusting the parameters of these models. In particular, we present experimental results for rainforest environments, which can be the goal of many sensor networks monitoring applications. The impact of the proposed approach is shown by evaluating a localization solution. The results show that this procedure is necessary for a higher fidelity of simulation experiments.
Compactness properties of critical nonlinearities and nonlinear Schrödinger equations
Authors: Costa David G. , Marcos do Ó João , Tintarev K.
Published: April 2013

We prove the compactness of critical Sobolev embeddings with applications to nonlinear singular Schrödinger equations and provide a unified treatment in dimensions N > 2 and N = 2, based on a somewhat unexpectedly broad array of parallel properties between spaces $\smash{\mathcal{D}^{1,2}(\mathbb{R}^N)}$ and H10 of the unit disc. These properties include Leray inequality for N = 2 as a counterpart of Hardy inequality for N > 2, pointwise estimates by ground states r(2−N)/2 and $\smash{\sqrt{\log(1/r)}}$ of the respective Hardy-type inequalities, as well as compactness of the limiting Sobolev embeddings once the Sobolev norm is appended by a potential term whose growth at singularities exceeds that of the corresponding Hardy-type potential.