bluuebunny/crossref_metadata_2025 huggingface dataset:
P3HT/PCBM Bulk Heterojunction Solar Cells: Impact of Blend Composition and 3D Morphology on Device Performance
Authors: van Bavel Svetlana S. , Bärenklau Maik , de With Gijsbertus , Hoppe Harald , Loos Joachim
Published: April 2010

The performance of polymer solar cells (PSC) strongly depends on the 3D morphological organization of the donor and acceptor compounds within the bulk heterojunction active layer. The technique of electron tomography is a powerful tool for studying 3D morphology of the layers composed of poly(3‐hexylthiophene) (P3HT) and a fullerene derivative ([6,6]‐phenyl‐C61‐butyric acid methyl ester; PCBM), especially to quantify the amount and distribution of fibrillar P3HT nanocrystals throughout the volume of the active layer. In this study, electron tomography is used to characterize P3HT/PCBM layers with different blend compositions, both before and after thermal annealing. The power conversion efficiency of the corresponding PSCs is strongly dependent on the overall crystallinity of P3HT and the way P3HT crystals are distributed throughout the thickness of the active layer.
Highly Emissive and Electrochemically Stable Thienylene Vinylene Oligomers and Copolymers: An Unusual Effect of Alkylsulfanyl Substituents
Authors: Jeeva Shehzad , Lukoyanova Olena , Fox Athan , Dadvand Afshin , Rosei Federico , Perepichka Dmitrii F.
Published: April 2010

The synthesis, unexpected efficient photoluminescence, and reversible electrochemical p‐ and n‐doping of new conjugated thienylene vinylene materials functionalized with alkylsulfanyl substituents poly(trithienylene vinylene) (PTTV) and poly(dithienylvinyl‐co‐benzothiadiazole) (PDTVB) along with dithienylvinylene‐based oligomers is reported. The materials are studied by thermal and X‐ray diffraction analysis, optical spectroscopy, cyclic voltammetry, and spectroelectrochemistry. Organic field‐effect transistors (OFETs) are fabricated with PTTV and PDTVB. The polymers, prepared by Stille polycondensation, exhibit good thermal stability and a photoluminescent quantum yield in the range 34%–68%. Low bandgaps (1.5–1.8 eV), estimated by optical and electrochemical measurements along with high stability of both redox states, suggest that these structures are promising materials for photovoltaic applications. OFETs fabricated with PDTVB reveal a hole mobility of 7 × 10−3 cm2 V−1 s−1 with on/off ratio 105, which are comparatively high values for completely amorphous polymer semiconductors.
A Mutant D‐Fructose‐6‐Phosphate Aldolase (Ala129Ser) with Improved Affinity towards Dihydroxyacetone for the Synthesis of Polyhydroxylated Compounds
Authors: Castillo José A. , Guérard‐Hélaine Christine , Gutiérrez Mariana , Garrabou Xavier , Sancelme Martine , Schürmann Melanie , Inoue Tomoyuki , Hélaine Virgil , Charmantray Franck , Gefflaut Thierry , Hecquet Laurence , Joglar Jesús , Clapés Pere , Sprenger Georg A. , Lemaire Marielle
Published: April 2010

A mutant of D‐fructose‐6‐phosphate aldolase (FSA) of Escherichia coli, FSA A129S, with improved catalytic efficiency towards dihydroxyacetone (DHA), the donor substrate in aldol addition reactions, was explored for synthetic applications. The kcat/KM value for DHA was 17‐fold higher with FSA A129S than that with FSA wild type (FSA wt). On the other hand, for hydroxyacetone as donor substrate FSA A129S was found to be 3.5‐fold less efficient than FSA wt. Furthermore, FSA A129S also accepted glycolaldehyde (GA) as donor substrate with 3.3‐fold lower affinity than FSA wt. This differential selectivity of both FSA wt and FSA A129S for GA makes them complementary biocatalysts allowing a control over donor and acceptor roles, which is particularly useful in carboligation multi‐step cascade synthesis of polyhydroxylated complex compounds. Production of the mutant protein was also improved for its convenient use in synthesis. Several carbohydrates and nitrocyclitols were efficiently prepared, demonstrating the versatile potential of FSA A129S as biocatalyst in organic synthesis.
An Efficient Domino Synthesis of Quinoxalin‐2(1H)‐ones via an SNAr/Coupling/Demesylation Reaction Catalyzed by Copper(I) as Key Step
Authors: Chen Dingben , Bao Weiliang
Published: April 2010

An efficient copper‐catalyzed method for the synthesis of quinoxalin‐2(1 H)‐ones derivatives via domino SNAr/coupling/demesylation reaction of N‐(2‐halophenyl)methylsulfonamides with 2‐halo amides has been developed. Various quinoxalinones with diversity at three positions on their scaffold have been obained, and the method is valuable for the construction of this kind of molecules with biological and pharmaceutical activities.
Highly Efficient Asymmetric Three‐Component Vinylogous Mannich Reaction Catalyzed by a Chiral Scandium(III)‐ N,N′‐Dioxide Complex
Authors: Zhang Qi , Hui Yonghai , Zhou Xin , Lin Lili , Liu Xiaohua , Feng Xiaoming
Published: April 2010

The asymmetric three‐component vinylogous Mannich reaction of an acyclic silyl dienol ester, an aldehyde and 2‐aminophenol was accomplished using a chiral N,N′‐dioxide‐scandium(III) complex as the catalyst. A variety of aldehydes were found to be suitable substrates for the reaction and the desired δ‐amino‐α,β‐unsaturated esters were obtained in 90–99% yields with good to excellent enantioselectivities (up to >99% ee) and complete regioselectivities. Moreover, the simple experimental procedures were air‐tolerant and convenient. The present catalytic process provides the potential for large‐scale syntheses of the chiral δ‐amino‐α,β‐unsaturated esters.
Ferrocenyl‐Aryl Based trans‐Chelating Diphosphine Ligands: Synthesis, Molecular Structure and Application in Enantioselective Hydrogenation
Authors: Schuecker Raffael , Mereiter Kurt , Spindler Felix , Weissensteiner Walter
Published: April 2010

Potentially trans‐chelating diphosphine ligands based on a ferrocenyl‐aryl backbone were synthesised in a four‐step sequence and the molecular structures in the solid state of two representatives were determined by X‐ray diffraction. High throughput screening of these ligands in rhodium‐, ruthenium‐ and iridium‐mediated hydrogenations of a variety of alkenes and ketones revealed that these ligands can deliver high enantioselectivity for alkenes (up to 98% ee) but are less selective when ketones are used as the substrates. The coordination behaviour of one ligand in its square planar palladium and platinum dichloride complexes was studied by 31P NMR and only trans‐chelated complexes, together with oligomeric by‐products, were observed. Reaction with the (p‐cymene)ruthenium dichloride dimer, [RuCl2(p‐cymene)]2, resulted in a mixture of diastereomeric complexes.
Efficient and General Synthesis of 3‐Aminoindolines and 3‐Aminoindoles via Copper‐Catalyzed Three‐Component Coupling Reaction
Authors: Chernyak Dmitri , Chernyak Natalia , Gevorgyan Vladimir
Published: April 2010

An efficient three‐component coupling (TCC) reaction toward a variety of 3‐aminoindoline and 3‐aminoindole derivatives has been developed. This cascade transformation proceeds via the copper‐catalyzed coupling reaction between 2‐aminobenzaldehyde, a secondary amine, and an alkyne leading to a propargylamine intermediate which, under the reaction conditions, undergoes cyclization into the indoline core. The latter, upon treatment with a base, smoothly isomerizes into the indole. Alternatively, the indole can directly be synthesized in a one‐pot sequential reaction.
Intangible effort and performance: the case of the French wine industry
Authors: Amadieu Paul , Viviani Jean‐Laurent
Published: April 2010

This study investigates to what extent intangible investments have a positive impact on French wine companies' financial performance. French wine companies are small‐ and medium‐sized enterprises (SMEs), so the task is (a) to measure their intangible expenses and capital, and (b) to estimate their impact on companies' performances. The authors then analyze the effect of property structures (cooperatives and corporations) and business activities on the intensity of the relationship between intangibility and performance.

Relationships between intangibles and performance were tested empirically by means of a questionnaire carried out in 2005–2006. Questionnaire data were completed using financial statements for 207 companies whose activity included one or more stages in the production and marketing of wine.

Using MANOVA and the production function approach, the authors found evidence that intangible proxies had a negative impact on the firms' economic performance measurements and a positive impact on commercial performance for intermediate values of intangible ratios. They also found that production functions were very different with regard to legal status and business activity, but that the negative impact of intangible proxies remained. © 2010 Wiley Periodicals, Inc.
Association of ZDHHC8 polymorphisms with smooth pursuit eye movement abnormality
Authors: Shin Hyoung Doo , Park Byung Lae , Bae Joon Seol , Park Tae Joon , Chun Ji Yong , Park Chul Soo , Sohn Jin‐Wook , Kim Bong‐Jo , Kang Yeo‐Hwa , Kim Jae Won , Kim Ki‐Hoon , Shin Tae‐Min , Woo Sung‐Il
Published: April 2010

The zinc finger DHHC domain‐containing protein 8 (ZDHHC8) is located in the 22q11 microdeletion region and may contribute to the behavioral deficit associated with 22q11 deletion syndrome. Although polymorphisms of ZDHHC8 have been reported to be associated with the risk of schizophrenia, those associations are still controversial. This study was performed to validate the genetic association of ZDHHC8 polymorphisms with the risk of schizophrenia, and also to scrutinize the association with smooth pursuit eye movement (SPEM) abnormality in a Korean population. Five SNPs of ZDHHC8 were genotyped by TaqMan assay. Their genetic effects on the risk of schizophrenia were analyzed in 354 patients and 396 controls using allele‐based χ2 analyses. Association of ZDHHC8 polymorphisms with SPEM abnormality among 166 schizophrenic patients were analyzed using multiple regressions. No ZDHHC8 polymorphisms were found to be associated with the risk of schizophrenia. However, four SNPs and one haplotype (ht4) were strongly associated with the risk of SPEM abnormality even after multiple correction (P = 0.00005–0.0007, Pcorr = 0.0001–0.002). The results of the present study provide the first evidence that ZDHHC8 on the 22q11 locus might have influence on SPEM function of schizophrenia patients in a Korean population and may provide a new clue for understanding differential effects of candidate genes in schizophrenia. © 2010 Wiley‐Liss, Inc.
Apoptosis‐inducing factor deficiency sensitizes dopaminergic neurons to parkinsonian neurotoxins
Authors: Perier Celine , Bové Jordi , Dehay Benjamin , Jackson‐Lewis Vernice , Rabinovitch Peter S. , Przedborski Serge , Vila Miquel
Published: April 2010

Objective

Mitochondrial complex I deficits have long been associated with Parkinson disease (PD). However, it remains unknown whether such defects represent a primary event in dopaminergic neurodegeneration.

Methods

Apoptosis‐inducing factor (AIF) is a mitochondrial protein that, independently of its proapoptotic properties, plays an essential physiologic role in maintaining a fully functional complex I. We used AIF‐deficient harlequin (Hq) mice, which exhibit structural deficits in assembled complex I, to determine whether primary complex I defects linked to AIF depletion may cause dopaminergic neurodegeneration.

Results

Despite marked reductions in mitochondrial complex I protein levels, Hq mice did not display apparent alterations in the dopaminergic nigrostriatal system. However, these animals were much more susceptible to exogenous parkinsonian complex I inhibitors, such as 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP). Subtoxic doses of MPTP, unable to cause damage to wild‐type animals, produced marked nigrostriatal dopaminergic degeneration in Hq mice. This effect was associated with exacerbated complex I inhibition and increased production of mitochondrial‐derived reactive oxygen species (ROS) in Hq brain mitochondria. The antioxidant superoxide dismutase‐mimetic compound tempol was able to reverse the increased susceptibility of Hq mice to MPTP. Supporting an instrumental role for mitochondrial‐derived ROS in PD‐related neurodegeneration, transgenic mice overexpressing mitochondrially targeted catalase exhibited an attenuation of MPTP‐induced mitochondrial ROS and dopaminergic cell death.

Interpretation

Structural complex I alterations linked to AIF deficiency do not cause dopaminergic neurodegeneration but increase the susceptibility of dopaminergic neurons to exogenous parkinsonian neurotoxins, reinforcing the concept that genetic and environmental factors may interact in a common molecular pathway to trigger PD. ANN NEUROL 2010;68:184–192
Effect of organoclays on the properties of polyurethane/clay nanocomposite coatings
Authors: Jin Hua , Wie Jeong Jae , Kim Sung Chul
Published: April 2010

Linear, one‐binding‐site or two‐binding‐site (N+) organifiers with two hydroxyl end groups were synthesized, and novel organoclays were prepared through a cation‐exchange reaction between pristine sodium montmorillonite and the synthesized organifiers. After sonication of the as‐prepared organoclay in N,N′‐dimethylformamide for 10 min, the average size of the clay decreased to about 1 μm. The X‐ray diffraction patterns confirmed that the d‐spacing of the silicate layers of the organoclay expanded from 1.1 to about 1.9 nm and the peak intensity decreased with the molecular weight of the organifier increasing. Polyurethane/clay nanocomposites were synthesized by a one‐shot polymerization method. Both intercalated and exfoliated structures of the layered silicates in the polyurethane matrix were observed from transmission electron microscopy micrographs, and the d‐spacing ranged from 4 to 10 nm. The thermal and mechanical properties of the nanocomposite were enhanced by the introduction of the organoclay into the polyurethane matrix. An approximately 40–46°C increase in the onset decomposition temperature, a 200% increase in the tensile strength with a 0.5 wt % clay loading, and a 49% increase in Young's modulus with a 3 wt % clay loading were achieved. The effects of the molecular weight and the number of binding sites of the organifier on the properties of the nanocomposites were also evaluated. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Retracted: Mechanical and thermal properties enhancement of polycarbonate nanocomposites prepared by melt compounding
Authors: Nayak Sanjay K. , Mohanty Smita , Samal Sushanta K.
Published: April 2010

The following article from the Journal of Applied Polymer Science, “Mechanical and thermal properties enhancement of polycarbonate nanocomposites prepared by melt compounding” by Sanjay K. Nayak, Smita Mohanty, and Sushanta K. Samal, published online on 7 April 2010 in Wiley Online Library (J. Appl. Polym. Sci. 2010, 117, 2101; http://onlinelibrary.wiley.com/doi/10.1002/app.31222/full), has been retracted by agreement between the authors, the journal's editors, and Wiley Periodicals, Inc. The retraction has been agreed due to significant overlap with respect to another article, “Effect of hydrogen bonding on the rheology of polycarbonate/organoclay nanocomposites,” by Kyung Min Lee, and Chang Dae Han, published online on 19 June 2003 in Polymer (2003, 44, 4573).
Thermal, morphological, and mechanical characterization of novel carbon nanofiber‐filled bismaleimide composites
Authors: Faraz M. I. , Bhowmik S. , De Ruijter C. , Laoutid F. , Benedictus R. , Dubois Ph. , Page J. V. S. , Jeson S.
Published: April 2010

Novel carbon nanofiber (CNF) ‐filled bismalemide composites were fabricated by a thermokinetic mixing method. The thermal and mechanical properties of composites containing 1 wt % and 2 wt % CNFs were investigated. Thermogravimetric analysis demonstrated that minimal improvement in thermal stability of the nanocomposites was obtained by the addition of CNFs. Dynamic mechanical analysis showed an increase in storage modulus (E′) and glass transition temperature (Tg) upon incorporation of nanofibers. Limiting oxygen index (LOI) has also been found to increase with incorporation of CNFs. Morphological studies of fractured surfaces of the composites has been carried out by scanning electron microscopy to determine the effect of fiber content and dispersion on the failure mechanism. In general, good dispersion was observed, along with agglomeration at some points and some fiber matrix interfacial debonding. A decrease in mechanical strength has been observed and debonding was found as the main failure mechanism. Further research outlook is also presented. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Swelling kinetic study and characterization of crosslinked hydrogels containing silver nanoparticles
Authors: Ahmed Enas M. , Aggor Fatma S.
Published: April 2010

The ammonium persulfate induced polymerization of acrylamide in the presence of silver nitrate (AgNO3) and N,N′‐methylenebisacrylamide as a crosslinking agent were used to prepare crosslinked hydrogels containing silver ions. Subjecting this hydrogel to reduction with sodium hydroxide brought to focus the nanosilver hydrogel composites. Characterization of the latter, including proof of existence of silver nanoparticles in the hydrogel, was made. The number of silver nanoparticles embedded in the hydrogel matrix was higher at higher concentration of AgNO3 used in the preparation of the nanosilver hydrogel composite. The characterization was performed by the use of ultraviolet–visible spectroscopy and transmission electron microscopy. The swellability of the hydrogel containing nanosilver particles was also studied, and the dependence of the swellability on the abundance of silver nanoparticles in the hydrogel composite was verified. It was further disclosed that the kinetic model matched the experimental data; meanwhile, the diffusion of water into the hydrogel was non‐Fickian type. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Mycophenolic acid area under the curve correlates with disease activity in lupus patients treated with mycophenolate mofetil
Authors: Zahr Noël , Arnaud Laurent , Marquet Pierre , Haroche Julien , Costedoat‐Chalumeau Nathalie , Hulot Jean‐Sébastien , Funck‐Brentano Christian , Piette Jean‐Charles , Amoura Zahir
Published: April 2010

Objective

Mycophenolic acid (MPA) is the active metabolite of mycophenolate mofetil (MMF), which is widely used to treat systemic lupus erythematosus (SLE). In transplantation, MPA area under the plasma concentration–time curve from 0 to 12 hours (MPA AUC0–12) is correlated with clinical outcome. We undertook the present study to assess possible relationships between SLE activity and MPA AUC0–12.

Methods

Using a Bayesian estimator, MPA AUC0–12 was determined in 71 consecutive SLE patients (61 women and 10 men; mean ± SD age 34 ± 10 years) receiving a stable MMF dose. On the same day, SLE activity was assessed using the SLE Disease Activity Index (SLEDAI; active disease defined as a SLEDAI score ≥6) and the British Isles Lupus Assessment Group (BILAG) index (active disease defined as BILAG A or B).

Results

Two groups were studied: patients with active SLE (mean ± SD SLEDAI score 11.6 ± 4.4; n = 26) and patients with inactive SLE (mean ± SD SLEDAI score 1.9 ± 1.6; n = 45). MPA AUC0–12 correlated weakly with the dose of MMF (r = 0.33, P = 0.005). Mean ± SD MPA AUC0–12 in the group with active SLE was significantly lower than that in the group with inactive SLE (26.8 ± 13.6 μg.hour/ml versus 46.5 ± 16.3 μg.hour/ml; P < 0.0001). MPA AUC0–12 was negatively correlated with the SLEDAI (r = –0.64, P < 0.0001). In multivariate analysis, MPA AUC0–12 was the sole parameter associated with SLE activity (odds ratio 0.89 [95% confidence interval 0.83–0.96], P = 0.002). The MPA AUC0–12 threshold value of 35 μg.hour/ml was associated with the lowest risk of active SLE.

Conclusion

Our data show that SLE activity is strongly correlated with MPA AUC0–12. An individualized dosing regimen of MMF, with a target AUC0–12 of 35 μg.hour/ml, should be considered for SLE patients.
The programmed death 1/programmed death ligand 1 inhibitory pathway is up‐regulated in rheumatoid synovium and regulates peripheral T cell responses in human and murine arthritis
Authors: Raptopoulou Amalia P. , Bertsias George , Makrygiannakis Dimitrios , Verginis Panagiotis , Kritikos Iraklis , Tzardi Maria , Klareskog Lars , Catrina Anca I. , Sidiropoulos Prodromos , Boumpas Dimitrios T.
Published: April 2010

Objective

T cells play a major role in the pathogenesis of rheumatoid arthritis (RA). The programmed death 1 (PD‐1)/programmed death ligand 1 (PDL‐1) pathway is involved in peripheral tolerance through inhibition of T cells at the level of synovial tissue. The aim of this study was to examine the role of PD‐1/PDL‐1 in the regulation of human and murine RA.

Methods

In synovial tissue and synovial fluid (SF) mononuclear cells from patients with RA, expression of PD‐1/PDL‐1 was examined by immunohistochemistry and flow cytometry, while PD‐1 function was assessed in RA peripheral blood (PB) T cells after stimulation of the cells with anti‐CD3 and PDL‐1.Fc to crosslink PD‐1. Collagen‐induced arthritis (CIA) was induced in PD‐1−/− C57BL/6 mice, and recombinant PDL‐1.Fc was injected intraperitoneally to activate PD‐1 in vivo.

Results

RA synovium and RA SF were enriched with PD‐1+ T cells (mean ± SEM 24 ± 5% versus 4 ± 1% in osteoarthritis samples; P = 0.003) and enriched with PDL‐1+ monocyte/macrophages. PD‐1 crosslinking inhibited both T cell proliferation and production of interferon‐γ (IFNγ) in RA patients; PB T cells incubated with RA SF, as well as SF T cells from patients with active RA, exhibited reduced PD‐1–mediated inhibition of T cell proliferation at suboptimal, but not optimal, concentrations of PDL‐1.Fc. PD‐1−/− mice demonstrated increased incidence of CIA (73% versus 36% in wild‐type mice; P < 0.05) and greater severity of CIA (mean maximum arthritis score 5.0 versus 2.3 in wild‐type mice; P = 0.040), and this was associated with enhanced T cell proliferation and increased production of cytokines (IFNγ and interleukin‐17) in response to type II collagen. PDL‐1.Fc treatment ameliorated the severity of CIA and reduced T cell responses.

Conclusion

The negative costimulatory PD‐1/PDL‐1 pathway regulates peripheral T cell responses in both human and murine RA. PD‐1/PDL‐1 in rheumatoid synovium may represent an additional target for immunomodulatory therapy in RA.
A comparative study on communication structures of Chinese journals in the social sciences
Authors: Zhou Ping , Su Xinning , Leydesdorff Loet
Published: April 2010

We argue that the communication structures in the Chinese social sciences have not yet been sufficiently reformed. Citation patterns among Chinese domestic journals in three subject areas—political science and Marxism, library and information science, and economics—are compared with their counterparts internationally. Like their colleagues in the natural and life sciences, Chinese scholars in the social sciences provide fewer references to journal publications than their international counterparts; like their international colleagues, social scientists provide fewer references than natural sciences. The resulting citation networks, therefore, are sparse. Nevertheless, the citation structures clearly suggest that the Chinese social sciences are far less specialized in terms of disciplinary delineations than their international counterparts. Marxism studies are more established than political science in China. In terms of the impact of the Chinese political system on academic fields, disciplines closely related to the political system are less specialized than those weakly related. In the discussion section, we explore reasons that may cause the current stagnation and provide policy recommendations.
The quality index for radar precipitation data: a tower of Babel?
Authors: Einfalt Thomas , Szturc Jan , Ośródka Katarzyna
Published: April 2010

One of the quantitative metrics of quality of radar measurements of precipitation is the quality index (QI): a field of numbers whose values depend on the quality. Such an approach is operationally used in some national meteorological services. Difficulties in using this approach can be observed due to hardware and software differences and continuous quality control algorithm improvement. An overall review of commonly used approaches and connected difficulties is made. The challenges in hydrological applications using the QI are listed, as the technique is used to generate precipitation field ensembles. Recommendations for future common considerations are suggested. Copyright © 2010 Royal Meteorological Society
Berechnung einer Kombinierten Pfahl‐Plattengründung am Beispiel des Hochhauses “Skyper” in Frankfurt/Main
Authors: Richter Thomas , Lutz Bernd
Published: April 2010

Am Bespiel des Hochhauses “Skyper” wurden durch den Unterausschuss “Kombinierte Pfahl‐Platten‐ und Pfahlgruppengründungen” des DIN verschiedene Berechnungsverfahren zur Berechnung einer Kombinierten Pfahl‐Plattengründung angewendet. Die Ergebnisse werden verglichen und diskutiert, wobei sich für den vorliegenden Fall herausstellte, dass sowohl numerische Verfahren als auch vereinfachte Verfahren, die auf der Halbraumtheorie basieren, akzeptable Ergebnisse liefern. Für eine Auswahl der geotechnischen Berechnungsverfahren wurden Federmodelle für die Abbildung der Reaktion der Baugrundoberfläche und der Pfähle abgeleitet und mit Ansatz dieser Federmodelle die Fundamentplatte bemessen. Auf dieser Grundlage gibt der Unterausschuss eine Empfehlung zur Anwendung von Berechnungsverfahren.

Calculation of a piled raft foundation as a case study for the high rise building “Skyper” in Frankfurt/Main. Various calculation methods were applied on the piled raft foundation of the high rise building ”Skyper“. The results are compared and discussed. Numerical methods as well as simplified methods based on the elastic half space theory lead in the actual case to reasonable results. With the derived subgrade reaction modulus and pile stiffness the raft reinforcement was computed. A recommendation for the application of numerical and simplified methods is given.
Der Bauingenieur Karl Bernhard
Authors: Dicleli Cengiz
Published: April 2010

Die AEG‐Turbinenhalle wurde 1909 fertiggestellt. Sie gilt allgemein als Werk des berühmten Architekten Peter Behrens, der 1907 bis 1914 Chef‐Designer und ‐Architekt der weltweit operierenden Firma AEG war. Anlässlich dieses Jahrestages wird der Ingenieur und Miterbauer der Halle, der Bauingenieur Karl Bernhard vorgestellt, der bei Konzeption und Errichtung des Bauwerkes konstruktiv und gestalterisch eine ganz entscheidende Rolle gespielt hat. Auch anhand von z. T. noch nicht veröffentlichten Untersuchungsergebnissen wird dargelegt, dass der Anteil von Karl Bernhard qualitativ und quantitativ viel größer ist, als es ihm seitens der Bau‐ und Kunstgeschichte bisher zugebilligt wird. Dabei geht es in erster Linie darum, dieses Phänomen als ein Ergebnis der unterschiedlichen Interessen von Architekten und Bauingenieuren, aber auch von Bau‐ und Kunsthistorikern zu verstehen.

Karl Bernhard — engineer and builder of the AEG‐Turbine Hall. The AEG‐Turbine Hall was realized in 1909. Generally the hall is considered to be the doing of the renowned architect Peter Behrens, who was the head designer and architect of the world wide operating company AEG. On the occasion of this anniversary the engineer and co‐builder will be presented, who relating to the construction and the design, played a very important part in developing the concept and realizing the building. Also, based on partly unreleased results of scientific studies the fact will be pointed out, that Bernard’s share of work was qualitatively and quantitatively much larger than conceded to him on part of art and building history. The point is to put across the fact, that this phenomena, is the result of different interests of architects and engineers and of building and art historians.
Morphological study of the fetal parotid duct and buccinator muscle and the relationship to salivary secretion
Authors: Amano Kaori , Moriyama Hiroshi , Shimada Kazuyuki , Matsumura George
Published: April 2010

The parotid glands secrete about 25% of all saliva produced. In the presence of a stimulus, the amount of saliva secreted from the parotid gland increases to 50%. A decrease in the amount of produced saliva due to aging and parotiditis results in a dry mouth. Therefore, the parotid duct is important to maintaining a healthy oral cavity. In human adults, the parotid duct, ∼6–8‐cm long, travels over the masseter muscle and penetrates the buccinator muscle to enter the oral cavity. Although there have been various studies regarding the parotid gland, only few suggest a functional role of the parotid duct, especially its area of penetration of the buccinator muscle. In this study, 34 fetal specimens ranging from 4 to 10 months of age at death were dissected for anatomical and histological examinations. The area of the parotid duct penetrating the buccinator muscle was fully formed in 5‐month‐old fetuses. This study found buccinator muscle fibers invading the parotid duct wall near its opening in 6‐month‐old fetuses and older. Our results support the claim that the buccinator muscle may act as a sphincter, playing a role in regulating and possibly preventing the reflux of salivary secretions into the parotid duct. Clin. Anat. 23:642–648, 2010. © 2010 Wiley‐Liss, Inc.
No Product Design without Process Design (Control)?
Authors: Stelzer T. , Ulrich J.
Published: April 2010

Product design is an active area of research. However, the term product design is non‐uniformly discussed in the literature, especially in the field of industrial crystallization. There is often a distinction between product design and process design. Due to that fact there is an unclear situation which leaves room for discussions. This review should help to find a more clear position. The problem is that the interrelation of product and process design quite often is underestimated in the literature. Therefore, the interrelations are highlighted here based on four examples. The examples selected are randomly taken from the entire field of crystallization (commodities, solvates, polymorphs, batch crystallization). The principles and conclusions discussed can, however, be transferred to other non‐touched areas where product and process design are considered. It is stated that “no product design is possible without process design (control)”.
The Diels–Alder Reaction of 4,6‐Dinitrobenzofuroxan with 1‐Trimethylsilyloxybuta‐1,3‐diene: A Case Example of a Stepwise Cycloaddition
Authors: Lakhdar Sami , Terrier François , Vichard Dominique , Berionni Guillaume , El Guesmi Nizar , Goumont Régis , Boubaker Taoufik
Published: April 2010

The reaction of 4,6‐dinitrobenzofuroxan (DNBF) with 1‐trimethylsilyloxybuta‐1,3‐diene (8) is shown to afford a mixture of [2+4] diastereomeric cycloadducts (10, 11) through stepwise addition–cyclization pathways. Zwitterionic intermediate σ‐adduct 9, which is involved in the processes, has been successfully characterized by 1H and 13C NMR spectroscopy and UV/visible spectrophotometry in acetonitrile. A kinetic study has been carried out in this solvent that revealed that the rate of formation of 9 nicely fits the three‐parameter equation log k=s(E+N) developed by Mayr to describe the feasibility of nucleophile–electrophile combinations. This significantly adds to the NMR spectroscopic evidence that the overall cycloadditions take place through a stepwise mechanism. The reaction has also been studied in dichloromethane and toluene. In these less polar solvents, the stability of 9 is not sufficient to allow direct characterization by spectroscopic methods, but a kinetic investigation supports the view that stepwise processes are still operating. An informative comparison of our reaction with previous interactions firmly identified as prototype stepwise cycloadditions is made on the basis of the global electrophilicity index, ω, defined by Parr within the density functional theory, and highlighted by Domingo et al. as a powerful tool for understanding Diels–Alder reactions.
Störeinfluss durch Schlieren bei der Tropfengrößenmessung an Zweistoffdüsen durch Laserbeugungsspektrometrie
Authors: Mescher A. , Walzel P.
Published: April 2010

Bei der Charakterisierung von Sprays aus Zweistoffdüsen mittels Laserbeugungsspektrometrie können verfälschte Messergebnisse durch lokal fluktuierende Brechungsindizes (Schlieren) im Gasstrahl auftreten. Sie bewirken eine Streuung des Laserlichtes, die nicht auf das Spray, sondern allein auf das Gas zurückzuführen ist. Es wird eine in der Praxis bewährte Methode für optimierte Messungen vorgestellt.
Opportunistic MAC layer design with stochastic Petri Nets for multimediaad hocnetworks
Authors: Escheikh M. , Barkaoui K.
Published: April 2010

Providing optimal resource utilization while minimizing costs involved for wireless networks remains a challenging issue. Particularly mobilead hocenvironments subject to multi‐path fading and characterized by a dynamic topology need better resource management mechanisms. The focus of this paper is the performance evaluation of IEEE 802.11e MAC layer modeling under slow time‐varying Rayleigh fading channel via both layered and multi‐layered design approaches via a non‐Markovian Stochastic Petri Nets modeling. We propose two MAC IEEE 802.11e models considering service differentiation features. The first one is non cross‐layer based, whereas the second is cross‐layer based. The cross‐layer design approach adopted permits us to deal with both collisions and fading. We show the impact of the virtual load on the expected throughput. Compared to the conventional approach, our cross‐layered design approach provides significant performance gains. Copyright © 2010 John Wiley & Sons, Ltd.
Power generation confirmation of induction motors and influence on islanding detection devices
Authors: Igarashi Hironobu , Sato Takashi , Miyamoto Kazunori , Kurokawa Kousuke
Published: April 2010

Photovoltaic generation systems must have protection devices and islanding detection devices if they are connected to utility lines of the electric power company. This is regulated in national technological requirement guidelines and the electric equipment technology standards. Islanding detection devices are installed to detect blackouts due to events such as ground faults and short circuits in utility lines. When an islanding detection device detects a power blackout, the photovoltaic generation system must be stopped immediately. It is known that islanding detection devices cannot detect islanding if induction motors are present among the loads. We investigated the influence of induction motors on islanding detection devices and found that when the frequency decreases after a utility line failure, induction motors change over to generator mode, thus compensating the active power imbalance and suppressing voltage variation. In addition, if the postfault frequency is adjusted by PLL control so as to maintain a fixed power factor, induction motors suppress this frequency change, thus extending islanding operation. It is clear from the above results that induction motors are more likely to produce islanding phenomena than static loads. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(4): 8–18, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20962
A proposal of a power distortion compensator using a matrix converter
Authors: Tamada Shunsuke , Itoh Jun‐ichi
Published: April 2010

Recently, renewable resource supplies, such as fuel cells, photovoltaic cells, wind power, and engine generators for distributed power systems have been studied intensely. Conventional compensators with switching devices are constructed based on a voltage source inverter using six arms. Therefore, conventional power quality compensators require a large electrolytic capacitor in the DC link part of the equipment. The use of a large capacitor hinders downsizing efforts and the lowering of equipment costs.

Direct converters, which do not have a large electrolytic capacitor and an initial charge circuit, can be used to realize downsizing and lowering of equipment costs, when compared with conventional converters.

This paper proposes a new application of a matrix converter to a PM generator for power quality compensation, such as reactive power compensation, harmonic current, and power interruption. The novel point of this work is that the matrix converter provides reactive power with harmonic current. Simulated and experimental results confirm that the matrix converter can maintain high performance the same as a conventional active filter and an uninterruptible power supply (UPS). © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(4): 37–44, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20972
Neural network‐based PID gain tuning of chemical plant controller
Authors: Abe Yoshihiro , Konishi Masami , Imai Jun , Hasegawa Ryusaku , Watanabe Masanori , Kamijo Hiroaki
Published: April 2010

Plant control systems are now highly automated and are used in many industries. The control performance changes with the passage of time because of deterioration of plant facilities. For this reason, human experts tune the control system to improve overall plant performance. In this study, a PID control system for the oil refining chemical plant process is discussed. In oil refining, thousands of control loops are used in plants in order to keep the product quality at the desired value and to assure the safety of plant operation. Due to the ambiguity of the interference between control loops, it is difficult to estimate the plant dynamical model accurately. Using a neuro emulator and a recurrent neural networks model (RNN model) for emulation and tuning of parameters, a PID gain tuning system for a chemical plant controller is constructed. Numerical experiments using actual plant data demonstrate the effect of the proposed method. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(4): 28–36, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20973
Thermal characteristics of 3kV, 600A 4H‐SiC flat‐package pn diodes
Authors: Ogata Syuji , Takayama Daisuke , Asano Katsunori , Sugawara Yoshitaka
Published: April 2010

3kV, 600A 4H‐SiC high‐temperature flat‐package diodes have been developed for use in electricity supply. They consist of a pressure contact flat package and include five 6 mm × 6 mm SiC diode chips. These flat‐package diodes have a thermal resistance of 0.21 deg/W, which is ten times the silicon thermal resistance, because the SiC diode chip is smaller than a Si diode chip. In order to lower the thermal resistance, it is necessary to increase the number of SiC chips in the flat package due to the difficulty of making a large‐area SiC chip. The SiC pn flat package diode can achieve the same thermal resistance value at only half the chip area. The transient thermal impedance becomes saturated at nearly 1 s. In contrast, the Si diode's transient thermal impedance is saturated at 50 s. If a short circuit current flows for 50 ms, the SiC pn flat package diode withstands greater pulse loads than the Si diode at temperatures above$\hbox{Tjmax} = 200 \ ^{\circ}\hbox{C}$. For example, the SiC diode withstands 2.3 times as much energy as the Si diode at$\hbox{Tjmax} = 500 \ ^{\circ}\hbox{C}$. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(4): 1–7, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20978
Functional plasticity and robustness are essential characteristics of biological systems: Lessons learned from KLRG1‐deficient mice
Authors: Jonjic Stipan
Published: April 2010

Killer cell lectin‐like receptor G1 (KLRG1) receptor is considered to be a marker of terminally differentiated NK and T cells and is strongly induced by viral and other infections. KLRG1 is a C‐type lectin‐like inhibitory receptor, which interacts with members of the cadherin family of molecules leading to the inhibition of T‐ and NK‐cell function. A study in this issue of the European Journal of Immunology addresses the role of KLRG1 in the maturation and differentiation of NK and T cells in vivo. Using KLRG1‐deficient mice generated by homologous recombination, the study reveals that KLRG1 is dispensable for NK‐ and CD8+ T‐cell differentiation and function in vivo. This interesting finding is discussed in this Commentary in light of the plasticity and robustness of immune response mechanisms.
Magnesium Triimidosulfonates from Grignard Reagents
Authors: Schulz Thomas , Stalke Dietmar
Published: April 2010

The triimidosulfonate complexes [(thf)MgX(NtBu)3SR]2 (1: R = methyl, X = Br; 2: R = n‐butyl, X = Cl; 3: R = phenyl, X = Cl; 4: R = benzyl, X = Cl) can be obtained very pure and in good yield upon treatment of the sulfur triimide S(NtBu)3 with the appropriate Grignard reagent RMgX. Changing the solvent from thf to toluene results in elimination of MgBr2 from 1 and generates the new complex [Mg{(NtBu)3SMe}2] (5). Complexes 1–5 should be good precursors for a variety of heterobimetallic complexes since transmetallation reactions are well established for this compound class and the third imido group is in an ideal position to coordinate a second metal. The triimidosulfinate ligands accommodate the requirements of the added organic group by either changing the twist between both ligands in the dimer or even changing the structural motif, as exemplified by 3. NMR investigations in solution confirm this conformational freedom and the adaptability of these ligands to a metal as electronically "hard" as magnesium.
Retro‐Claisen Condensation with FeIII as Catalyst under Solvent‐Free Conditions
Authors: Rao Chitturi Bhujanga , Rao Dasireddi Chandra , Babu Dokuburra Chanti , Venkateswarlu Yenamandra
Published: April 2010

An iron(III) salt catalyzed retro‐Claisen condensation between an alcohol and a 1,3‐diketone was investigated. The mechanism involves the formation of a metal‐induced six‐membered cyclic transition state and cleavage of the C–C bond. Regioselective esterification and one‐pot conversion of silyl ethers into esters with good yields was observed. Simple reaction conditions, high yields, and broad scope of the reaction illustrate the good synthetic utility of this method.
Chiral Ionic Liquids Bearing O‐Silylated α,α‐Diphenyl (S)‐ or (R)‐Prolinol Units: Recoverable Organocatalysts for Asymmetric Michael Addition of Nitroalkanes to α,β‐Enals
Authors: Maltsev Oleg V. , Kucherenko Alexandr S. , Beletskaya Irina P. , Tartakovsky Vladimir A. , Zlotin Sergei G.
Published: April 2010

Chiral ionic liquids bearing O‐silylated α,α‐diphenyl (S)‐ or (R)‐prolinol units tagged to the imidazolium cation were synthesized and their activity as catalysts in the Michael addition of nitroalkanes to α,β‐unsaturated aldehydes was evaluated. Respective (S) or (R) adducts were obtained in the reactions in high yields (up to 95 %) and with high enantioselectivity (up to 99 % ee). Remarkably, the immobilized organocatalysts could be used five times without any decrease in product yields or ee values. (R)‐Michael adducts could be easily transformed into the most active (R) enantiomers of medications Phenibut, Baclofen, and Rolipram for the treatment of CNS disorders.
Stereoselective determination of midodrine and desglymidodrine in culture medium: Application to a biotransformation study employing endophytic fungi
Authors: Barth Thiago , Pupo Mônica Tallarico , Borges Keyller Bastos , Okano Laura Tiemi , Bonato Pierina Sueli
Published: April 2010

A CE method was developed and validated for the stereoselective determination of midodrine and desglymidodrine in Czapek culture medium to be applied to a stereoselective biotransformation study employing endophytic fungi. The electrophoretic analyses were performed using an uncoated fused‐silica capillary and 70 mmol/L sodium acetate buffer solution (pH 5.0) containing 30 mmol/L heptakis (2, 3, 6‐tri‐O‐methyl)‐β‐CD as running electrolyte. The applied voltage and temperature used were 15 kV and 15°C, respectively. The UV detector was set at 200 nm. The sample preparation was carried out by liquid–liquid extraction using ethyl acetate as extractor solvent. The method was linear over the concentration range of 0.1–12 μg/mL for each enantiomer of midodrine and desglymidodrine (r≥0.9975). Within‐day and between‐day precision and accuracy evaluated by RSDs and relative errors, respectively, were lower than 15% for all analytes. The method proved to be robust by a fractional factorial design evaluation. The validated method was used to assess the midodrine biotransformation to desglymidodrine by the fungus Phomopsis sp. (TD2), which biotransformed 1.1% of (−)‐midodrine to (−)‐desglymidodrine and 6.1% of (+)‐midodrine to (+)‐desglymidodrine.
Preparation, characterization, and boron adsorption behavior of gluconate‐intercalated hydrotalcite
Authors: Yan Chun‐Yan , Yi Wen‐Tao
Published: April 2010

Gluconate‐intercalated hydrotalcites were prepared from precursor by ion‐exchange method. The products were characterized by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and energy dispersive spectroscopy (EDS) studies. This kind of new adsorbent was applied to adsorb boron in the refined brine, and the conditions influencing its adsorption amount were investigated. The experimental results showed that the adsorbent synthesized in this article had higher adsorption amount of boron than the precursor without gluconate intercalation, and the adsorption amount increased with increasing the contact time, boron concentration, and the pH whereas decreased with increasing chloride concentration and temperature. The adsorbent can be well regenerated by calcination and reintercalation of the gluconate into the calcinated product. Furthermore, the kinetic studies were also investigated. The pseudo‐first‐order, pseudo‐second‐order, and intraparticle diffusion models were used to fit the experimental data, and the results showed that the pseudo‐first‐order model best described the boron adsorption process. © 2010 American Institute of Chemical Engineers Environ Prog, 2010
Antimicrobial activity of essential oils: the possibilities of TLC–bioautography
Authors: Horváth Györgyi , Jámbor Noémi , Végh Anna , Böszörményi Andrea , Lemberkovics Éva , Héthelyi Éva , Kovács Krisztina , Kocsis Béla
Published: April 2010

Essential oils are well‐known for their antimicrobial activity against different plant and human pathogenic microorganisms. The results of the most commonly used antimicrobial assays are very different; sometimes their reliability is questionable, therefore standardized methods need to be used to solve this problem. The present study aims at the phytochemical characterization of some essential oils (thyme, lavender, eucalyptus, spearmint and cinnamon) that are important from the therapeutic and economic aspects and the optimized microbiological investigation of the effect of essential oils on human and plant pathogenic microorganisms. The chemical composition of the essential oils was analysed with thin‐layer chromatography (TLC) and their composition was controlled by gas chromatography (GC). The antibacterial effect was investigated using the TLC‐bioautographic method. The solvents applied in TLC developing systems were also tested. Our results showed that toluene, ethyl acetate, ethanol and chloroform as solvents used in the assay had no inhibiting effect on the test bacteria. The antibacterial activity of thyme, lavender and cinnamon oils and their main components (thymol, carvacrol, linalool, eugenol) was observed in the case of two plant pathogenic bacteria (Xanthomonas campestris pv. vesicatoria and Pseudomonas syringae pv. phaseolicola) and some human pathogens (Staphylococcus epidermidis, S. saprophyticus and two strains of S. aureus, including one methicillin‐resistant strain). On the whole, the antibacterial activity of essential oils can be related to their most abundant components, but the effect of the minor components should also be taken into consideration. Direct bioautography is more cost‐effective and compares better with traditional microbiological laboratory methods (e.g. disc‐diffusion, agar‐plate technique). Copyright © 2010 John Wiley & Sons, Ltd.