bluuebunny/crossref_metadata_2025 huggingface dataset:
Cholesterol‐/Estradiol‐Appended Alkynylplatinum(II) Complexes as Supramolecular Gelators: Synthesis, Characterization, Photophysical and Gelation Studies
Authors: Li Yongguang , Lam Elizabeth Suk‐Hang , Tam Anthony Yiu‐Yan , Wong Keith Man‐Chung , Lam Wai Han , Wu Lixin , Yam Vivian Wing‐Wah
Published: June 2013

A series of cholesterol‐/estradiol‐appended alkynylplatinum(II) complexes with tridentate N‐donor ligands, based on 2,6‐bis(1‐alkylpyrazol‐3‐yl)pyridine, has been synthesized and characterized by 1H NMR spectroscopy, FAB‐mass spectrometry, and elemental analysis. Their photophysical properties have also been investigated. Computational studies have been performed to provide insights into the nature of the electronic transitions. Some of the complexes have been found to form stable thermo‐ and mechanoresponsive supramolecular gels.
Intrinsic Structural Disorder in Cytoskeletal Proteins
Authors: Guharoy Mainak , Szabo Beata , Martos Sara Contreras , Kosol Simone , Tompa Peter
Published: June 2013

Cytoskeleton, the internal scaffold of the cell, displays an exceptional combination of stability and dynamics. It is composed of three major filamentous networks, microfilaments (actin filaments), intermediate filaments (neurofilaments), and microtubules. Together, they ensure the physical and structural stability of the cell, whereby also mediating its large‐scale structural rearrangements, motility, stress response, division, and internal transport. All three cytoskeletal systems are built upon the same basic design: they have a central repetitive scaffold assembled from folded building elements, surrounded and regulated by accessory regions/proteins that regulate its formation and mediate its countless interactions with its environment, serving to send regulatory signals to and from the cytoskeleton. Here, we elaborate on the idea that the opposing features of stability and dynamics are also manifest in the dichotomy of the structural status of its components, the core being highly structured and the accessory proteins/regions being highly disordered, and are responsible for most of the regulatory (post‐translational) input promoting adaptive responses and providing dynamics necessary for each of the cytoskeletal systems. This pattern entails special consequences, in which the manifold functional advantages of structural disorder, most pronounced in regulatory and signaling functions, are all exploited by nature. © 2013 Wiley Periodicals, Inc.
Detection of B‐cell populations with monotypic light chain expression in cerebrospinal fluid specimens from patients with multiple sclerosis by polychromatic flow cytometry
Authors: Vafaii Poopak , DiGiuseppe Joseph A.
Published: June 2013

Background

Flow cytometric immunophenotyping is an established method for the detection of occult leptomeningeal disease in patients with aggressive B‐cell non‐Hodgkin lymphoma, and is increasingly being used in the evaluation of patients without an established diagnosis of lymphoma who present with signs and/or symptoms referable to the central nervous system. However, the specificity of flow cytometric immunophenotyping in the identification of monoclonal B‐cell populations in cerebrospinal fluid (CSF) has not been systematically evaluated.

Methods

We searched a consecutive series of CSF specimens submitted to our laboratory for polychromatic (8‐color) flow cytometric immunophenotyping between June, 2010 and December, 2012 for cases in which a B‐cell population with monotypic immunoglobulin light chain expression was detected in patients without clinical or radiographic evidence of lymphoma.

Results

A B‐cell population with monotypic light chain expression was identified in CSF specimens from three patients whose subsequent clinical and radiologic evaluation provided no evidence for lymphoma. In all three patients, a diagnosis of multiple sclerosis was ultimately rendered upon completion of the clinical evaluation.

Conclusions

We conclude that the detection of a B‐cell population with monotypic light chain expression in CSF by polychromatic flow cytometry is not diagnostic of occult leptomeningeal involvement by a B‐cell non‐Hodgkin lymphoma. Moreover, these findings suggest that monotypic B‐cell populations detectable by polychromatic flow cytometry may be prevalent in patients with multiple sclerosis, and highlight the importance of clinicopathologic correlation in this application of polychromatic flow cytometry. © 2013 International Clinical Cytometry Society
A reconstructing approach to end‐to‐end network traffic based on multifractal wavelet model
Authors: Nie Laisen , Jiang Dingde , Guo Lei , Xu Zhengzheng
Published: June 2013

This paper studies the reconstructing method of end‐to‐end network traffic. Due to the development of current communication networks, our networks become more complex and heterogeneous. Meanwhile, because of time‐varying nature and spatio‐temporal correlations of the end‐to‐end network traffic, to obtain it accurately is a great challenge. We propose to exploit discrete wavelet transforms and multifractal analysis to reconstruct the end‐to‐end network traffic from time–frequency domain. First, its time–frequency properties can be characterized in detail by discrete wavelet transforms. And then, we combine discrete wavelet transforms and multifractal analysis to reconstruct end‐to‐end network traffic from link loads. Furthermore, our method needs to measure end‐to‐end network traffic to build the statistical model named multifractal wavelet model. Finally, simulation results from the real backbone networks suggest that our method can reconstruct the end‐to‐end network traffic more accurately than previous methods. Copyright © 2013 John Wiley & Sons, Ltd.
Efficient slice‐aware H.264/AVC video transmission over time‐driven priority networks
Authors: Baccaglini E. , Marchetto G. , Tillo T. , Olmo G.
Published: June 2013

This paper proposes a multimedia streaming architecture that combines network and video technologies to handle video traffic over multi‐hop access networks. In this context, resource overprovision typical of current quality of service approaches will become a limiting factor because of the increasing spread of bandwidth‐intensive multimedia applications. The proposed scheme adopts a time‐driven priority scheduling at network nodes and exploits slice classification at the video encoder to differentiate packets. The service guarantees offered by time‐driven priority, together with the packet classification, significantly reduce congestion and increase the video quality at the receiver with respect to the traditional differentiated services (DiffServ) approach, also achieving high resource utilization. This is an important result, as current DiffServ‐based architectures are far from obtaining such resource utilization in conjunction with reasonable delays and jitters. Copyright © 2013 John Wiley & Sons, Ltd.
Europa wächst zusammen – auch in der Mauerwerksnormung (?)
Authors: Kranzler Thomas
Published: June 2013

Der Beitrag gibt einen kurzen Überblick über die Entwicklung der europäischen Prüf‐, Produkt‐ und Bemessungsnormen von und für Mauerwerksprodukte, beginnend mit der Bauproduktenrichtlinie 1988 bis hin zur Einführung der Eurocodes für Mauerwerksbau 2014. Stellvertretend für alle Mauerwerksprodukte/‐industrien wird aus Sicht der Mauerziegelindustrie dieser lange und bisweilen zähe Weg ausgehend von den deutschen Normen DIN 105 und DIN 1053 bis hin zu den europäischen Normen DIN EN 771‐1 und DIN EN 1996 (Eurocode 6) aufgezeigt.

Die Ende der 1980er‐Jahre bestehende Auffassung, bereits in wenigen Sitzungen europaweit akzeptierte Entwurfsfassungen der europäischen Normen vorzulegen, scheiterte an der Tatsache, dass sich verschiedene nationale Interessen in Form von unterschiedlichen Prüfverfahren, unterschiedlichen Anforderungen und Schutzniveaus, aber auch gänzlich unterschiedlichen Konzepten hinsichtlich der Beschreibung der Produkte gegenüberstanden.

In einem langwierigen und zähen Harmonisierungsprozess sahen sich die Vertreter der deutschen Mauerwerksindustrie einer Reihe von Fragestellungen und Unwägbarkeiten (technisch, vor allem aber “politisch“) gegenüber.

Das Ergebnis dieses mittlerweile knapp 25 Jahre andauernden Prozesses sind – ausgehend von rund 60 Seiten zu Beginn – über 500 (!) Seiten europäisch harmonisierte Prüf‐, Produkt‐ und Bemessungsnormen von und für Mauerziegel.

Europe is growing together – in the standardization of/for masonry as well (?). The article gives a short overview of the development of the European test‐, product‐ and design standards of masonry. It starts with the Construction Products Directive (CPD) and ends with the implementation of the Eurocode 6 in Germany. This lengthy proceeding will be shown by taking the example of the German clay masonry industry and their way, from the German standards DIN 105 and DIN 1053 through to the European standards EN 771‐1 and EN 1996 (Eurocode 6). Started on basis of around 60 pages of relevant national standards for clay masonry, the results of this by now 25 year long process are circa 500 (!) pages of relevant European harmonised standards.
Fire resistance assessment of masonry structures – Structural fire design of masonry buildings according to the Eurocodes
Authors: Meyer Udo
Published: June 2013

This paper summarizes a presentation given at the European Commission Workshop “Structural fire design” held on November 27th and 28th, 2012 in Brussels. For more information visit: http://eurocodes.jrc.ec.europa.eu/showpage.php?id=2012_11_WS_Fire

Feuerwiderstand von Mauerwerksbauten – Brandschutz‐Bemessung von Mauerwerk nach den Eurocodes. Der Beitrag ist die Schriftfassung eines Vortrags anlässlich des Workshops “Structural fire design“ der Europäischen Kommission am 27. und 28. November 2012 in Brüssel. Weitere Informationen unter: http://eurocodes.jrc.ec.europa.eu/showpage.php?id=2012_11_WS_Fire
Die europäische Normung von Kalksandsteinen in prEN 771‐2:2013 mit Blick auf die neue Bauproduktenverordnung
Authors: Schlundt Andreas
Published: June 2013

Die neue Bauproduktenverordnung tritt mit Geltung aller wesentlichen Artikel der Verordnung ab 01. Juli 2013 vollumfänglich in Kraft. Ab diesem Zeitpunkt ändert sich damit auch die “Deklaration“ von Kalksandsteinen. Neben dem bekannten CE‐Kennzeichen, mit dem die Produkte gekennzeichnet werden, ist nunmehr zusätzlich für jedes Produkt auch eine Leistungserklärung erforderlich. Hierzu waren in der europäischen Kalksandstein‐Norm EN 771‐2 einige Anpassungen erforderlich. Insbesondere wurde bei der Überarbeitung auch ein Kurzkennzeichen‐System entwickelt und genormt, mit dem zukünftig eine kurze und praktikable CE‐Kennzeichnung am Produkt möglich ist.

European standardization of calcium silicate units in prEN 771‐2: 2013 with a view to the new Construction Products Regulation. The new Construction Products Regulation including all essential articles becomes effective on 01. July 2013. Herewith the “declaration” of calcium silicate units changes from that date. In addition to the already known CE‐marking affixed to the products from now on a Declaration of Performance is required. For this purpose changes in the European standard for calcium silicate units were necessary. During the revision especially a designation system was developed and standardized, that will lead in the future to a short and practical CE‐marking on the product.
Brandschutz mit Mauerwerk: Veröffentlichung von DIN EN 1996‐1‐2/NA – Auswirkungen für die Baupraxis
Authors: Meyer Udo
Published: June 2013

Mit der DIN EN 1996‐1‐2 mit Nationalem Anhang wird der bisherige Stand der DIN 4102‐4 in Verbindung mit DIN 1053‐1 für Mauerwerk ohne wesentliche Änderung für das Bemessungsergebnis fortgeschrieben. Der Beitrag informiert über einige neue Begrifflichkeiten.

Fire design with masonry: Publication of DIN EN 1996‐1‐2/NA – consequences for the application. DIN EN 1996‐1‐2/NA preserves the existing practice resulting from the design with DIN 4102‐4 in conjunction with DIN 1053‐1. The paper highlights some of the new definitions in the standard.
Zum Eurocode 6 – Fragen und Antworten
Authors: Jäger Wolfram
Published: June 2013

Unter dieser Rubrik werden Fragen beantwortet, die bei der Einarbeitung in den EC 6 entstehen. Die Wiedergabe erfolgt in jedem Falle anonymisiert. Sofern es um Verständnisfragen und Hintergrundinformationen geht, werden sie von den Beiratsmitgliedern beantwortet. Handelt es sich um Auslegungsfragen, wird der zuständige NABau‐Ausschuss NA 005‐06‐01 AA “Mauerwerksbau“ (Sp CEN/TC 125, CEN/TC 250/SC 6) mit einbezogen.

Mit dem Leserforum zum EC 6 soll der Praxis die Einarbeitung in das neue Normenpaket mit seinen Nationalen Anhängen erleichtert werden. Auch Sie können als Leser gern von dieser Rubrik Gebrauch machen und Ihre Fragen stellen (mauerwerk@ernst‐und‐sohn.de).

Questions concerning the introduction of the EC 6. Under this heading questions are answered, arising from the application of EC 6. The questions are expressing anonymous in all cases. Provided that they concern the understanding and background information the answers will be given by members of the editorial board. If the questions are dealing with the interpretation of clauses of EC 6 the responsible code committee NA 005‐06‐01 AA “Masonry construction” (Sp CEN/TC 125, CEN/TC 250/SC 6) will be involved.

The practice should get help for the adjustment in the EC 6 and its National Annexes with this new category of contributions. The readers are invited to avail oneself of this chance very active (mauerwerk@ernst‐und‐sohn.de).

Die nachfolgenden Fragen und Antworten beziehen sich auf den Teil 1‐1 [1] sowie Teil 3 [3] von DIN EN 1996 zusammen mit dem zugehörigen Nationalen Anhang [2] und [4].
Genetic by environment interactions affect plant–soil linkages
Authors: Pregitzer Clara C. , Bailey Joseph K. , Schweitzer Jennifer A.
Published: June 2013

The role of plant intraspecific variation in plant–soil linkages is poorly understood, especially in the context of natural environmental variation, but has important implications in evolutionary ecology. We utilized three 18‐ to 21‐year‐old common gardens across an elevational gradient, planted with replicates of five Populus angustifolia genotypes each, to address the hypothesis that tree genotype (G), environment (E), and G × E interactions would affect soil carbon and nitrogen dynamics beneath individual trees. We found that soil nitrogen and carbon varied by over 50% and 62%, respectively, across all common garden environments. We found that plant leaf litter (but not root) traits vary by genotype and environment while soil nutrient pools demonstrated genotype, environment, and sometimes G × E interactions, while process rates (net N mineralization and net nitrification) demonstrated G × E interactions. Plasticity in tree growth and litter chemistry was significantly related to the variation in soil nutrient pools and processes across environments, reflecting tight plant–soil linkages. These data overall suggest that plant genetic variation can have differential affects on carbon storage and nitrogen cycling, with implications for understanding the role of genetic variation in plant–soil feedback as well as management plans for conservation and restoration of forest habitats with a changing climate.
Changes in the genetic structure of Atlantic salmon populations over four decades reveal substantial impacts of stocking and potential resiliency
Authors: Perrier Charles , Guyomard René , Bagliniere Jean‐Luc , Nikolic Natacha , Evanno Guillaume
Published: June 2013

While the stocking of captive‐bred fish has been occurring for decades and has had substantial immediate genetic and evolutionary impacts on wild populations, its long‐term consequences have only been weakly investigated. Here, we conducted a spatiotemporal analysis of 1428 Atlantic salmon sampled from 1965 to 2006 in 25 populations throughout France to investigate the influence of stocking on the neutral genetic structure in wild Atlantic salmon (Salmo salar) populations. On the basis of the analysis of 11 microsatellite loci, we found that the overall genetic structure among populations dramatically decreased over the period studied. Admixture rates among populations were highly variable, ranging from a nearly undetectable contribution from donor stocks to total replacement of the native gene pool, suggesting extremely variable impacts of stocking. Depending on population, admixture rates either increased, remained stable, or decreased in samples collected between 1998 and 2006 compared to samples from 1965 to 1987, suggesting either rising, long‐lasting or short‐term impacts of stocking. We discuss the potential mechanisms contributing to this variability, including the reduced fitness of stocked fish and persistence of wild locally adapted individuals.
A Kinetic Study on the Substitution for Acetonitrile at the trans‐to‐μ‐Oxido Sites in a Bis(μ‐acetato)(μ‐oxido)diruthenium(III) Dipositive Complex: Dissociative–Associative Transition of the Activation Mode for the Substitution of Pyridine Derivatives
Authors: Ido Yohei , Sakaguchi Kiyoshi , Tasei Minako , Minami Suguru , Sawamoto Hiroki , Fujihara Takashi , Nagasawa Akira
Published: June 2013

A new diruthenium(III) complex [RuIII2(μ‐O)(μ‐CH3CO2)2(bpy)2(CH3CN)2](PF6)2 [1(PF6)2, bpy = 2,2′‐bipyridine] has been synthesized, and the dynamic behaviour of CH3CN at the trans‐to‐μ‐oxido sites were investigated by 1H NMR and UV/Vis spectroscopy at 0–60 °C under 0.101–147 MPa in CH3CN. The solvent exchange in CD3CN at 5 °C gave the rate constant k = 2.43 × 10–3 s–1 and the activation parameters ΔH‡ = 124 kJ mol–1 and ΔS‡ = +150 J K–1 mol–1, which point to a dissociative mechanism (Id or D). The ligand substitution of pyridine (py) in CD3CN at 30 °C, yielding [RuIII2(μ‐O)(μ‐CH3CO2)2(bpy)2(py)2](PF6)2 [2a(PF6)2], gave a rate constant per site of k = 1.56 × 10–2 M–1 s–1, and the activation parameters ΔH‡ = 81 kJ mol–1 and ΔS‡ = –13 J K–1 mol–1. The substitution of various pyridine derivatives (Rpy) for CH3CN in 1(PF6)2 exhibited varying activation parameters: ΔH‡ ranged from 66 to 92 kJ mol–1, ΔS‡ ranged from –51 to +22 J K–1 mol–1, and ΔV‡ (for Rpy with R = H, 3‐Ac, 4‐NH2, 4‐CN, 3‐CN) ranged from +1.3 to +3.2 cm3 mol–1. These results suggest an interchange (I) mechanism for the substitution of Rpy, for which its strong electron‐donating ability is responsible. A compensation effect is seen between ΔH‡ and ΔS‡, and both have linear relationships with the Hammett parameters. The substituent R electronically influences the strength of the interaction of Rpy with Ru center in the transition state to shift the activation mode to a dissociative (Id) or an associative (Ia) interchange.
Synthesis of an Octa‐tert‐butylphthalocyanine: A Low‐Aggregating and Photochemically Stable Photosensitizer
Authors: Gobo Nicholas R. S. , Brocksom Timothy J. , Zukerman‐Schpector Julio , de Oliveira Kleber T.
Published: June 2013

The synthesis of a new octa‐tert‐butylphthalocyanine is described. First, the 4,5‐di‐tert‐butylphthalonitrile building block was synthesized in a six‐step approach, in which the last step is a three reaction domino sequence. Then, this phthalonitrile was cyclotetramerized to furnish a new phthalocyanine dye, which presented no aggregation in solution and good photophysical properties.
Access to Di‐ and Trisubstituted Oxazoles by NBS‐Mediated Oxidative Cyclisation of N‐Acyl Amino Acid Derivatives
Authors: Bathula Surendar Reddy , Reddy Muktapuram Prathap , Viswanadham K. K. Durga Rao , Sathyanarayana Pochampalli , Reddy Maddi Sridhar
Published: June 2013

A remarkably simple method for the synthesis of di‐ and trisubstituted functionalised oxazoles under metal‐ and catalyst‐free conditions is described. An iterative bromination and debromination of N‐acylated amino acid derivatives with NBS as the sole reagent cleanly led to various substituted oxazoles.
(–)‐Isosteviol as a Versatile Ex‐Chiral‐Pool Building Block for Organic Chemistry
Authors: Lohoelter Christina , Weckbecker Magdalena , Waldvogel Siegfried R.
Published: June 2013

(–)‐Isosteviol is readily available in large quantities by the acidic treatment of a common alternative sweetener. The two functional groups of (–)‐isosteviol are presented on the same side of the ent‐beyerane scaffold with a mutual C–C distance of about 7 Å. Their unique concave arrangement experiences a strong asymmetric environment due to an adjacent methyl group. Consequently, this building block has found several applications in supramolecular chemistry and organocatalysis. These areas and the chemical modification of this scaffold as well as its biological activity are surveyed.
Amine‐Catalyzed Cascade Synthesis of 3,4‐Diunsubstituted Coumarins
Authors: Wei Jia , Wang Pengcheng , Jia Qianfa , Huang Jiaoyao , Du Zhiyun , Zhang Kun , Wang Jian
Published: June 2013

We disclose an efficient route to synthesize 3,4‐diunsubstituted coumarins through a cascade organocatalytic reaction. The reaction is catalyzed by using of a combination of benzylamine (10 mol‐%) and triethylamine (10 mol‐%). Various salicylaldehydes were tested, and the corresponding coumarin products were obtained in good to high yields under mild and metal‐free reaction conditions.
The effect of pH on the toxicity of zinc oxide nanoparticles to Folsomia candida in amended field soil
Authors: Waalewijn-Kool Pauline L. , Ortiz Maria Diez , Lofts Stephen , van Gestel Cornelis A.M.
Published: June 2013

The effect of soil pH on the toxicity of 30 nm ZnO to Folsomia candida was assessed in Dorset field soils with pHCaCl2 adjusted to 4.31, 5.71, and 6.39. To unravel the contribution of particle size and dissolved Zn, 200 nm ZnO and ZnCl2 were tested. Zinc sorption increased with increasing pH, and Freundlich kf values ranged from 98.9 (L/kg)1/n to 333 (L/kg)1/n for 30 nm ZnO and from 64.3 (L/kg)1/n to 187 (L/kg)1/n for ZnCl2. No effect of particle size was found on sorption, and little difference was found in toxicity between 30 nm and 200 nm ZnO. The effect on reproduction decreased with increasing pH for all Zn forms, with 28-d median effective concentrations (EC50s) of 553 mg Zn/kg, 1481 mg Zn/kg, and 3233 mg Zn/kg for 30 nm ZnO and 331 mg Zn/kg, 732 mg Zn/kg, and 1174 mg Zn/kg for ZnCl2 at pH 4.31, 5.71, and 6.39, respectively. The EC50s based on porewater Zn concentrations increased with increasing pH for 30 nm ZnO from 4.77 mg Zn/L to 18.5 mg Zn/L, while for ZnCl2 no consistent pH-related trend in EC50s was found (21.0–63.3 mg Zn/L). Porewater calcium levels were 10 times higher in ZnCl2-spiked soils than in ZnO-spiked soils. The authors' results suggest that the decreased toxicity of ZnCl2 compared with 30 nm ZnO based on porewater concentrations was because of a protective effect of calcium and not a particle effect. Environ Toxicol Chem 2013;32:2349–2355. © 2013 SETAC
Unique pattern of molt leads to low intraindividual variation in feather mercury concentrations in penguins
Authors: Brasso Rebecka L. , Drummond Bridgette E. , Borrett Stuart R. , Chiaradia André , Polito Michael J. , Rey Andrea Raya
Published: June 2013

The authors hypothesized that the catastrophic annual molt of penguins (Sphenisciformes) would lead to reduced intraindividual variation of mercury concentrations in body feathers. While mean mercury concentrations varied significantly among 8 penguin species, intraindividual variability did not differ among species and was 3 times lower than values observed in other seabirds. The findings of the present study suggest that a single body feather collected at random per individual can be adequate to estimate mercury exposure at the population level in penguins. Environ Toxicol Chem 2013;32:2331–2334. © 2013 SETAC
Effects of fluoride on growth, body composition, and serum biochemical profile in a freshwater teleost, Cyprinus carpio
Authors: Chen Jianjie , Cao Jinling , Wang Jundong , Jia Ruhui , Xue Wenjuan , Li Yundong , Luo Yongju , Xie Lingtian
Published: June 2013

Fluoride is ubiquitously distributed in natural waters. Elevated fluoride may cause histopathological changes and induce oxidative stress in the gills of the common carp (Cyprinus carpio). The present study further evaluates the effects of fluoride on growth performance, body composition, and biochemical measurements of C. carpio. The results showed that food intake, growth, serum osmolality, body composition, and biochemical measures in the blood were affected by fluoride. Weight gain rate and specific growth rate in the exposed fish decreased compared with those of the control fish. Levels of crude protein and crude lipids were reduced in the fluoride-exposed fish. The major ion levels in the sera of fluoride-exposed fish were severely disturbed, resulting in a lower osmolality. All the biochemical parameters measured in the blood were affected by the exposure to fluoride. Total protein, albumin, globulin, and glucose in fish exposed to 63.6 mg/L, 77.7 mg/L, and 124.4 mg/L were lower than those in the control fish. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were markedly increased in exposed fish compared with control. Taken together, the data showed that exposure to fluoride caused a suite of detrimental effects in C. carpio, which might lead to a decrease in growth and food utilization efficiency. The results of the present study indicated that high levels of fluoride could pose a threat to carp in the field. Environ Toxicol Chem 2013;32:2315–2321. © 2013 SETAC
Characterization of hyperalkaline fluids produced by low‐temperature serpentinization of mantle peridotites in the Oman and Ligurian ophiolites
Authors: Chavagnac Valérie , Monnin Christophe , Ceuleneer Georges , Boulart Cédric , Hoareau Guilhem
Published: June 2013

A regional survey of alkaline springs in Oman and Ligurian ophiolites shows that the alkaline water compositions significantly vary from one ophiolite to the other and within the same ophiolite. The first‐order correlation between the Na (and K) and Cl concentrations points to fluid compositions only partly due to evaporation. The scatter around the evaporation line implies that Na and Cl may not be conservative during the alteration of the ultramafic rocks. Mg is almost entirely depleted at pH > 10.5 as a result of serpentine formation within the ultramafic body and of brucite (and minor hydrotalcite) precipitation at the springs. Ca accumulates in the high‐pH fluids and is consumed by Ca‐carbonate formation at the springs, by mixing with river waters or by the CO2 supply from the atmosphere. Thermodynamic calculations show that brucite saturation is reached at pH values around 10.5 which triggers major changes in the water composition. The waters evolve from a quartz‐saturated low‐pH continental environment to a brucite‐dominated high‐pH serpentinizing system at low temperature. The highest water salinities are found in springs located along the basal thrust plane of the ophiolite. The highest Al concentrations are found in some springs located on the crustal side of the mantle/crust boundary. This poses the question of the hydrologic pathways and of the role of the mineralogical composition of the altered formations.
Lanthanide‐Catalyzed Selective Addition of Diethyl Phosphite to Chalcones
Authors: Zhang Aijiao , Cai Lijian , Yao Zhigang , Xu Fan , Shen Qi
Published: June 2013

Lanthanide‐catalyzed addition of diethyl phosphite with chalcones was achieved under mild conditions. The reaction exhibited good product selectivity using different catalysts. γ‐Oxophosphonates were obtained in high yields in the reactions catalyzed by Yb(OAr)3(THF)2, while those catalyzed by [(Me3Si)2N]3La(μ‐Cl)Li(THF)3 afforded 1,2‐oxaphospholane‐5‐phosphonates as the main products in moderate to good yields. This methodology provides facile and practical approaches to the corresponding organophosphorus compounds with biological interest.
Targeting the therapeutic effects of exercise on redox‐sensitive mechanisms in the vascular endothelium during tumor progression
Authors: Wolff Gretchen , Toborek Michal
Published: June 2013

The American Cancer Society estimated 1.5 million new cancer cases in the United States in 2012. Although the exact number is not known, it is estimated that brain metastases occur in 20–40% of cancer patients (39). Owing to the complexity of development and the variation in tumor etiology, therapy options have been limited for a number of cancers, whereas progressive treatments have been successful for some malignancies. Combining treatment strategies has shown potential to increase positive outcomes; however, cancer remains a formidable diagnosis with no true cure. Many researchers have focused on alternative forms of cancer prevention or treatment to slow cancer progression. Studies have shown that with moderate, regular exercise signaling pathways associated with increased antioxidant activity and cellular repair are upregulated in vascular tissue; however, the physiological mechanisms are poorly understood. The purpose of this review is to examine the current literature to better understand the impact of exercise on cancer progression and tumor metastasis and discuss potential redox‐related signaling in the vasculature that may be involved. © 2013 IUBMB Life, 65(7):565–571, 2013.
Transcription‐coupled DNA supercoiling in defined protein systems and inE. coli topAmutant strains
Authors: Fulcrand Geraldine , Zhi Xiaoduo , Leng Fenfei
Published: June 2013

Transcription by RNA polymerases can stimulate (−) DNA supercoiling bothin vitroand inEscherichia coli topAstrains. This phenomenon has been successfully explained by a “twin‐supercoiled‐domain” model of transcription in which (+) supercoils are produced in front of the transcribing RNA polymerase and (−) supercoils behind it. Previously, it has been shown that certain sequence‐specific DNA‐binding proteins potently stimulate transcription‐coupled DNA supercoiling (TCDS) in anin vitroprotein system. These results are consistent with a topological barrier model where certain nucleoprotein complexes can form topological barriers that impede the diffusion and merger of independent chromosomal supercoil domains. Indeed, recent biochemical and single‐molecule results demonstrated the existence of nucleoprotein‐based DNA topological barriers, which are capable of dividing a DNA molecule into different topological domains. Additionally, recentin vivostudies showed that a transcriptional ensemble (including the transcribing RNA polymerase and the RNA transcript) alone is sufficient to cause a change in local DNA superhelicity. This topological change in local chromosome structure should have a great impact on the conformation and function of critical DNA sequence elements, such as promoters and DNA replication origins. In this article, we will also review recent progress by which TCDS is a critical stimulating force to activate transcription initiation from weak promoters, such as theSalmonella typhimurium leu‐500promoter. © 2013 IUBMB Life, 65(7):615–622, 2013.
Limitations of Global Morphometry in Predicting Trabecular Bone Failure
Authors: Stauber Martin , Nazarian Ara , Müller Ralph
Published: June 2013

Efforts in finding independent measures for accurate and reliable prediction of trabecular bone failure have led to the development of a number of morphometric indices characterizing trabecular bone microstructure. Generally, these indices assume a high homogeneity within the bone specimen. However, in the present study we found that the variance in bone volume fraction (BV/TV) in a single bone specimen can be relatively large (CV = 9.07% to 28.23%). To assess the limitations of morphometric indices in the prediction of bone failure for specimens in which the assumption of homogeneity is not met, we harvested 13 cadaveric samples from a single human spine. We tested these cylindrical samples using image-guided failure assessment (IGFA), a technique combining stepwise microcompression and time-lapsed micro–computed tomography (µCT). Additionally, we computed morphometric indices for the entire sample as well as for 10 equal subregions along the anatomical axis. We found that ultimate strength was equally well predicted by BV/TV of the entire sample (R2 = 0.55) and BV/TV of the weakest subregion (R2 = 0.57). Investigating three-dimensional animations of structural bone failure, we showed that two main failure mechanisms determine the competence of trabecular bone samples; in homogeneous, isotropic trabecular bone samples, competence is determined by a whole set of trabecular elements, whereas in inhomogeneous, anisotropic bone samples a single or a missing trabeculae may induce catastrophic failure. The latter failure mechanism cannot be described by conventional morphometry, indicating the need for novel morphometric indices also applicable to the prediction of failure in inhomogeneous bone samples. © 2014 American Society for Bone and Mineral Research.
Predictors of Fracture While on Treatment With Oral Bisphosphonates: A Population-Based Cohort Study
Authors: Prieto-Alhambra Daniel , Pagès-Castellà Aina , Wallace Gemma , Javaid M Kassim , Judge Andrew , Nogués Xavier , Arden Nigel K , Cooper Cyrus , Diez-Perez Adolfo
Published: June 2013

Although oral bisphosphonates (BPs) are highly effective in preventing fractures, some patients will fracture while on treatment. We identified predictors of such fractures in a population-based cohort of incident users of oral BPs. We screened the Sistema d‘Informació per al Desenvolupament de l‘Investigació en Atenció Primària (SIDIAP) database to identify new users of oral BPs in 2006–2007. SIDIAP includes pharmacy invoice data and primary care electronic medical records for a representative 5 million people in Catalonia (Spain). Exclusion criteria were the following: Paget disease; <40 years of age; and any antiosteoporosis treatment in the previous year. A priori defined risk factors included age, gender, body mass index, vitamin D deficiency, smoking, alcohol drinking, preexisting comorbidities, and medications. Fractures were considered if they appeared at least 6 months after treatment initiation. “Fractures while on treatment” were defined as those occurring among participants persisting for at least 6 months and with an overall high compliance (medication possession ratio ≥80%). Fine and Gray survival models accounting for competing risk with therapy discontinuation were fitted to identify key predictors. Only 7449 of 21,385 (34.8%) participants completed >6 months of therapy. Incidence of fracture while on treatment was 3.4/100 person-years (95% confidence interval [CI], 3.1–3.7). Predictors of these among patients persisting and adhering to treatment included: older age (subhazard ratio [SHR] for 60 to <80 years, 2.18 [95% CI, 1.70–2.80]; for ≥80 years, 2.5 [95% CI, 1.82–3.43]); previous fracture (1.75 [95% CI, 1.39–2.20] and 2.49 [95% CI, 1.98–3.13], in the last 6 months and longer, respectively); underweight, 2.11 (95% CI, 1.14–3.92); inflammatory arthritis, 1.46 (95% CI, 1.02–2.10); use of proton pump inhibitors (PPIs), 1.22 (95% CI, 1.02–1.46); and vitamin D deficiency, 2.69 (95% CI, 1.27–5.72). Even among high compliers, 3.4% of oral BP users will fracture every year. Older age, underweight, vitamin D deficiency, PPI use, previous fracture, and inflammatory arthritides increase risk. Monitoring strategies and/or alternative therapies should be considered for these patients. © 2014 American Society for Bone and Mineral Research.
Rigid Steiner Triple Systems Obtained from Projective Triple Systems
Authors: Grannell M. J. , Knor M.
Published: June 2013

It was shown by Babai in 1980 that almost all Steiner triple systems are rigid; that is, their only automorphism is the identity permutation. Those Steiner triple systems with the largest automorphism groups are the projective systems of orders. In this paper, we show that each such projective system may be transformed to a rigid Steiner triple system by at mostnPasch trades whenever.
Electrochemical synthesis of hydrogen peroxide with a three‐dimensional rotating cylinder electrode
Authors: González Pérez Omar , Bisang José M.
Published: June 2013

BACKGROUND

This work analyzes the synthesis of H2O2 from dilute NaOH solutions under 0.1 MPa O2 using a batch reactor with a three‐dimensional rotating cylinder electrode. The centrifugal force produces a radial co‐current flow of the gas and liquid phases. Thus, good mass transfer conditions are achieved and the O2 reduced to H2O2 is easily replenished in the liquid phase.

RESULTS

Experiments with a glassy carbon rotating disc electrode identified 0.5 mol L‐1 NaOH at 30°C as suitable operating conditions. Galvanostatic experiments with three‐dimensional rotating electrodes concluded that the best performance was obtained for a reticulated vitreous carbon structure of 100 ppi, at 40 mA cm‐2 of macrokinetic current density and 1000 rpm rotation speed. Long‐term experiments showed 79% current efficiency and 8.2 kWh kg‐1 specific energy consumption until 6 h of electrolysis, with 8.4 g L‐1 H2O2 concentration. However, the current efficiency decreases for longer electrolysis times and consequently the specific energy consumption is increased. Thus after 10 h electrolysis the concentrations were H2O2 10.4 g L‐1 and NaOH 1.41 mol L‐1.

CONCLUSION

A reactor having a three‐dimensional rotating cylinder electrode with co‐current oxygen and liquid flows inside the structure showed promising performance for H2O2 production. © 2013 Society of Chemical Industry
Beneficial metal stabilization mechanisms using simulated sludge incineration ash for ceramic products
Authors: Tang Yuanyuan , Liu Chengshuai , Shih Kaimin
Published: June 2013

BACKGROUND

This study explored the feasibility of a waste to resource strategy by using incineration ash of sewage/waste‐water treatment sludge as part of the raw materials for ceramic processing. Reactions between metal oxides (CuO, ZnO), common metal containing form in incineration ash, and kaolinite based ceramic raw materials (kaolinite, mullite) were observed. The metal incorporation behavior was determined using quantitative X‐ray diffraction analysis.

RESULTS

The optimal sintering temperature for copper incorporation was 1000°C, with CuAl2O4 phase dominating the system. For zinc incorporation, ZnAl2O4 and Zn2SiO4 formed in competition, with ZnAl2O4 found to predominate at temperatures higher than 1150°C. To determine the preferred phases for long‐term metal stability, a prolonged toxicity characteristic leaching procedure was carried out to quantify metal leaching performance and explore the leaching behavior. Metal leaching following incorporation in spinel leachates was significantly lower than those in oxide and silicate leachates, and the surface leaching behavior was also analyzed for the consideration of long‐term metal stability.

CONCLUSION

The overall results indicate that spinel formation is a preferred metal stabilization mechanism when incorporating sludge incineration ash into ceramic products and is also a key control step to safely implement this waste to resource strategy for a more sustainable engineering solution. © 2013 Society of Chemical Industry
Bacterial contamination of healthcare workers' uniforms: A randomized controlled trial of antimicrobial scrubs
Authors: Burden Marisha , Keniston Angela , Frank Maria G. , Brown Carrie A. , Zoucha Jeff , Cervantes Lilia , Weed Diane , Boyle Kathy , Price Connie , Albert Richard K.
Published: June 2013

BACKGROUND

Healthcare workers' (HCWs) uniforms become contaminated with bacteria during normal use, and this may contribute to hospital‐acquired infections. Antimicrobial uniforms are currently marketed as a means of reducing this contamination.

OBJECTIVE

To compare the extent of bacterial contamination of uniforms and skin when HCWs wear 1 of 2 antimicrobial scrubs or standard scrubs.

DESIGN

Prospective, randomized, controlled trial.

SETTING

University‐affiliated, public safety net hospital

PARTICIPANTS

Hospitalist physicians, nurse practitioners, physician assistants, housestaff, and nurses (total N = 105) working on internal medicine units.

INTERVENTION

Subjects were randomized to wear standard scrubs or 1 of 2 antimicrobial scrubs.

MEASUREMENTS

Bacterial colony counts in cultures taken from the HCWs' scrubs and wrists after an 8‐hour workday.

RESULTS

The median (interquartile range) total colony counts was 99 (66–182) for standard scrubs, 137 (84–289) for antimicrobial scrub type A, and 138 (62–274) for antimicrobial scrub type B (P = 0.36). Colony counts from participants' wrists were 16 (5–40) when they wore standard scrubs and 23 (4–42) and 15 (6–54) when they wore antimicrobial scrubs A and B, respectively (P = 0.92). Resistant organisms were cultured from 3 HCWs (4.3%) randomized to antimicrobial scrubs and none randomized to standard scrubs (P = 0.55). Six participants (5.7%) reported side effects to wearing scrubs, all of whom wore antimicrobial scrubs (P = 0.18).

CONCLUSIONS

We found no evidence that either antimicrobial scrub product decreased bacterial contamination of HCWs' uniforms or skin after an 8‐hour workday. Journal of Hospital Medicine 2013;8:380–385. © 2013 Society of Hospital Medicine
FUTURE: New strategies for hospitalists to overcome challenges in teaching on today's wards
Authors: Martin Shannon K. , Farnan Jeanne M. , Arora Vineet M.
Published: June 2013

Changes in the clinical learning environment under resident duty hours restrictions have introduced a number of challenges on today's wards. Additionally, the current group of medical trainees is largely represented by the Millennial Generation, a generation characterized by an affinity for technology, interaction, and group‐based learning. Special attention must be paid to take into account the learning needs of a generation that has only ever known life with duty hours. A mnemonic for strategies to augment teaching rounds for hospitalists was created using an approach that considers time limitations due to duty hours as well as the preferences of Millennial learners. These strategies to enhance learning during teaching rounds are Flipping the Wards, Using Documentation to Teach, Technology‐Enabled Teaching, Using Guerilla Teaching Tactics, Rainy Day Teaching, and Embedding Teaching Moments into Rounds (FUTURE). Hospitalists serving as teaching attendings should consider these possible strategies as ways to enhance teaching in the post‐duty hours era. These techniques appeal to the preferences of today's learners in an environment often limited by time constraints. Hospitalists are well positioned to champion innovative approaches to teaching in a dynamic and evolving clinical learning environment. Journal of Hospital Medicine 2013;8:409–413. © 2013 Society of Hospital Medicine
Ultra‐performance liquid chromatography MS/MS method for the determination of parabens in compost from sewage sludge: Comparison of the efficiency of two extraction techniques
Authors: Benítez‐Villalba Julio César , Zafra‐Gómez Alberto , Dorival‐García Noemí , Javier Camino‐Sánchez Francisco , Cantarero Samuel , Vílchez José Luis
Published: June 2013

The efficiency of two extraction techniques—ultrasound‐assisted extraction and pressurized liquid extraction—are compared and evaluated in the determination of parabens in compost samples. The extraction parameters for each technique were accurately optimized. The selected compounds were detected and quantified using ultra‐performance LC MS/MS, operating in negative ESI and in SRM mode. The analytes were separated in less than 5 min. Ethylparaben (ring‐13C6 labeled) was used as an internal standard. Two selective, sensitive, and accurate analytical methods were developed and validated. The LODs of the methods ranged from 3 to 7 ng/g and the LOQs from 10 to 23 ng/g, while inter‐ and intraday variability was under 6% in all cases. The methods were validated separately by using matrix‐matched calibration and recovery assays with spiked samples. Recovery rates ranged from 94.0 to 105.0%. Compost samples were taken from different composting plants. Although the statistical comparison demonstrated no statistically significant differences between the two extraction techniques, the method based on pressurized liquid extraction was more sensitive than the ultrasound extraction based method.
A direct sensitivity comparison between flow‐modulated comprehensive 2D and 1D GC in untargeted and targeted MS‐based experiments
Authors: Tranchida Peter Q. , Franchina Flavio A. , Zoccali Mariosimone , Bonaccorsi Ivana , Cacciola Francesco , Mondello Luigi
Published: June 2013

The present contribution is focused on the measurement of the analytical sensitivity attained in untargeted/targeted MS/MS experiments, performed using flow‐modulator comprehensive 2D and 1D GC. The comprehensive 2D experiment was performed by diverting part of the high flow (circa 80%) to flush the accumulation loop (about 28 mL/min) to waste, to reduce the gas flow entering the ion source. 1D analyses were performed through: (i) unmodulated and (ii) single column applications. An equivalent temperature program was applied in the modulated and unmodulated analyses, while a faster one was employed in the single column one. In all application types, the (same) triple quadrupole instrument was operated in the full‐scan and multiple reaction monitoring modes. A genuine sweet orange oil and the same sample spiked with 20 phytosanitary compounds were employed to reach the research objective. The results highlight the problems related to the flow modulation–MS combination. Specifically, it was found that sensitivity was on average three to four times higher in unmodulated and optimized single‐column applications.
Transient Absorption Spectroscopy Studies on Polythiophene–Fullerene Bulk Heterojunction Organic Blend Films Sensitized with a Low‐Bandgap Polymer
Authors: Löslein Heiko , Ameri Tayebeh , Matt Gebhard J. , Koppe Markus , Egelhaaf Hans J. , Troeger Anna , Sgobba Vito , Guldi Dirk M. , Brabec Christoph J.
Published: June 2013

Recently, the concept of near‐infrared sensitization is successfully employed to increase the light harvesting in large‐bandgap polymer‐based solar cells. To gain deeper insights into the operation mechanism of ternary organic solar cells, a comprehensive understanding of charge transfer–charge transport in ternary blends is a necessity. Herein, P3HT:PCPDTBT:PCBM ternary blend films are investigated by transient absorption spectroscopy. Hole transfer from PCPDTBT‐positive polarons to P3HT in the P3HT:PCPDTBT:PCBM 0.9:0.1:1 blend film can be visualized. This process evolves within 140 ps and is discussed with respect to the proposed charge‐generation mechanisms.

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Facile Synthesis of Free‐Standing Polymer Brush Films Based on a Colorless Polydopamine Thin Layer
Authors: Kohri Michinari , Shinoda Yoshihiro , Kohma Hiroto , Nannichi Yuri , Yamauchi Mitsuaki , Yagai Shiki , Kojima Takashi , Taniguchi Tatsuo , Kishikawa Keiki
Published: June 2013

A free‐standing polymer brush film with tailored thicknesses based on a colorless polydopamine (PDA) thin layer is prepared and characterized. The surface‐initiated atom transfer radical polymerization (ATRP) of 2‐hydroxyethyl methacrylate (HEMA) is performed on a PDA layer with thickness of ca. 6 nm, which generated an optically transparent and colorless free‐standing PHEMA brush film (1.5 cm × 1.5 cm). Because the cross‐linked PDA layer is used as the base for the polymer brushes, the reported method does not require cross‐linking the polymer brushes. The free‐standing film thicknesses of ≈16–75 nm are controlled by simply changing the ATRP reaction time. The results show that the free‐standing PHEMA brush film transferred onto a plate exhibits a relatively smooth surface and is stable in any solvent.

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