bluuebunny/crossref_metadata_2025 huggingface dataset:
Étude cinétique de l’adsorption du rouge de Congo sur une bentonite
Authors: Guiza Sami , Bagane Mohamed
Published: August 2013

L’avancement industriel et technologique à l'échelle mondiale a introduit des polluants de natures diverses dans l'eau. Les polluants peuvent être des contaminants organiques et des métaux lourds. Leur présence dans des effluents industriels où l'eau potable est un problème de santé publique en raison de leur absorption et, par la suite, leur accumulation dans l’organisme humain. Les règlements de pollution de l'eau exigent que les industries textiles réduisent considérablement la quantité de colorants dans leurs rejets. L'adsorption, procédé de traitement des eaux usées, exploite la capacité de quelques solides pour concentrer certaines substances sur leurs surfaces. Généralement, l’adsorbant le plus utilisé pour le traitement des effluents textiles est le charbon activé. La capacité de la bentonite pour enlever la couleur a été reconnue il y a quelque temps. Dans ce travail, nous avons étudié la cinétique d’adsorption d’un colorant acide, le rouge de Congo, en solution aqueuse sur un matériau argileux naturel (bentonite) dans un processus en lots. La concentration initiale du colorant était de 30 mg•L‑1 déterminée par une méthode spectrophotométrique. L’influence de certains paramètres, comme la vitesse d’agitation, la masse d’argile en solution, la concentration initiale du colorant et la granulométrie a été étudiée. Les résultats ont montré pour la vitesse d’adsorption : (i) une augmentation avec la vitesse d’agitation et la masse d’argile et, (ii) une décroissance avec la concentration initiale en colorant et la granulométrie. Cinq modèles de transport externe ont été étudiés et ont montré que l’ordre de grandeur du coefficient, kf, se trouve dans la gamme de 10‑5 à 10‑4•ms‑1.
Influence des fluctuations hydro-pluviométriques sur la production des sédiments : cas du bassin de la Haute Tafna
Authors: Megnounif Abdesselam , Ghenim Abderrahmane Nekkache
Published: August 2013

Les bassins versants des régions semi-arides méditerranéennes sont soumis à une variété de perturbations, comme la variabilité des précipitations et la dégradation du couvert végétal et, par conséquent, le potentiel érosif. Dans ce contexte, la méthode des doubles cumuls est utilisée pour observer la tendance de la production des sédiments en suspension. L’étude est menée sur le bassin versant de la Haute Tafna, situé au nord-ouest de l’Algérie et d’une superficie de 256 km2. L’évolution de la charge solide est expliquée en fonction des séries chronologiques des précipitations et des apports en eau aux échelles annuelle et saisonnière.

À l’instar du nord de l’Afrique, la baisse de la pluviométrie, qui a sévi dans la région depuis le milieu des années 1970, a induit une dégradation progressive de la couverture végétale. De ce fait, les pluies s’abattent souvent sur des sols nus, compacts et desséchés générant des débits de pointe élevés et une forte érosion concentrée.

Par ailleurs, un changement de comportement des saisons est confirmé dès les années 1990. Quoique faibles et moins réguliers, les apports pluviométriques durant la saison sèche ont doublé, et ce, malgré une tendance globale à la baisse des apports annuels. La dégradation progressive du couvert végétal, combinée avec l’augmentation des orages estivaux, a induit des changements dans le fonctionnement du bassin versant avec une plus grande susceptibilité à l’érosion. Pour des années particulières, une pluviométrie modérée a généré des écoulements et des flux sédimentaires considérables. À partir de la fin des années 1980, la production annuelle des sédiments est devenue sept fois plus importante que celle de la période d’avant, avec une augmentation quatre fois plus importante du taux de contribution de la saison sèche.
Régionalisation d'une méthode de prédétermination de crue sur l'ensemble du territoire français : la méthode SHYREG
Authors: Organde Didier , Arnaud Patrick , Fine Jean-Alain , Fouchier Catherine , Folton Nathalie , Lavabre Jacques
Published: August 2013

La méthode SHYREG a été développée pour la connaissance régionale des quantiles de débits de crue (débit de pointe et lames d'eau maximales écoulées sur les durées de 1 h à 72 h) pour les périodes de retour de 2 à 100 ans suivant une approche spatialisée. Elle associe un simulateur de pluies horaires et une modélisation simple pluie-débit, mis en oeuvre à une résolution kilométrique. Les quantiles de débits se déduisent directement des distributions de fréquence empiriques des valeurs maximales extraites des très longues chroniques de débit simulées. On obtient alors une base de quantiles de crues que l'on peut agréger à l'échelle de n'importe quel bassin versant, moyennant une règle d'abattement avec la surface. La régionalisation de la méthode a été réalisée sur la France métropolitaine, à l'exclusion de la Corse, en exploitant les données hydrométriques de 1 359 stations de jaugeage et des caractéristiques hydro-climatiques et hydrogéologiques spatialisées permettant de décrire la variabilité du paramètre saisonnier du modèle. Au final, cette régionalisation permet la connaissance des quantiles de débits de crue en tout bassin versant de la France métropolitaine avec une bonne restitution des quantiles de débit de pointe et journalier, pour les périodes de retour comprises entre 2 et 10 ans : un critère de Nash minimum de 80 % est obtenu sur les quantiles de débit de pointe pseudo-spécifique et de débit journalier spécifique des bassins versants non utilisés pour la régionalisation.
Extraction du plomb (II) par des membranes polymères à inclusion en utilisant l’Aliquat 336 comme transporteur
Authors: Sabba Nassila , Arous Omar , Akretche Djamel Eddine
Published: August 2013

Au cours de ce travail, nous avons étudié l’extraction liquide - liquide et le transport du plomb à travers des membranes polymériques en utilisant le chlorure de tricapryle ammonium (Aliquat 336) comme transporteur. L’extraction du plomb par Aliquat 336 nous a permis de mettre au point les conditions optimales d’extraction et de déterminer les rendements d’extraction. Les expériences d’extraction liquide - liquide ont montré qu’un maximum de rendement était obtenu après huit minutes d’agitation à une vitesse de 2 400 (rpm). Les pourcentages d’extraction obtenus varient entre 80 à 94 % et donc une très bonne élimination du plomb a été réalisée (la concentration initiale du plomb varie entre 2 10‑6 M et 30 10‑6 M). Nous avons préparé par la suite des membranes à base du polymère triacétate de cellulose (TAC) plastifiées par le tris-ethyl-hexyl-phosphate (TEHP) et modifiées par l’extractant Aliquat 336 utilisé comme transporteur. Les membranes élaborées ont été également caractérisées par spectroscopie infrarouge à transformée de Fourier (FTIR). Les valeurs obtenues pour les épaisseurs (entre 10 et 20 µm) et les densités sont tout à fait comparables à celles des supports commerciaux utilisés pour la préparation des membranes liquides supportées. L’ajout du plastifiant a donné une très bonne hydrophobie des membranes élaborées.

Les expériences du transfert du plomb à travers les nouvelles membranes ont montré que les flux augmentent considérablement avec la concentration du transporteur pour atteindre un maximum à partir de 10‑3 M. D’autres paramètres caractérisant le transport (concentration initiale du métal et le pH) ont été déterminés. Un bon rendement d’élimination du plomb a été obtenu dans la gamme de pH très acide (1 ≤ pH ≤ 2).
Traitement des effluents d’abattoir de viande rouge par électrocoagulation-flottation avec des électrodes en fer
Authors: Khennoussi Abdelaziz , Chaouch Mehdi , Chahlaoui Abdelkader
Published: August 2013

L’effluent de l’abattoir municipal de la ville de Meknès est caractérisé par une forte charge organique polluante et une coloration rouge due à la concentration élevée en sang. Les analyses physicochimiques et microbiologiques ont révélé des concentrations importantes en paramètres globaux de pollution, et une charge microbiologique marquée par la dominance des coliformes. La demande chimique en oxygène (DCO) moyenne est de 2 240 mg d’O2•L‑1. La concentration moyenne en azote total est de 290 mg•L‑1. Les orthophosphates sont à une concentration moyenne de 35 mg•L‑1. La matière extractible à l’hexane (MEH) varie entre 900 et 1 100 mg•L‑1. Les coliformes fécaux sont de 67•103 UFC•mL‑1.

Le traitement par électrocoagulation-flottation utilisant des électrodes plates de fer, avec une tension électrique de 12 V et un temps de contact de 25 min, a donné de bons résultats. Il a permis l’abattement de 92,6 % de DCO, 76,2 % d’azote total, et 95,4 % des orthophosphates. Les MEH sont éliminées à 62,5 % grâce au phénomène de flottation favorisé par le dégagement des bulles d’hydrogène issues de la réduction de l’eau à la cathode, et le brassage de l’effluent par agitation dans la cellule électrolytique. Ce processus a permis également la décoloration de cet effluent, illustrée par une diminution de l'absorption à 450 nm supérieure à 90 %, et une diminution remarquable de l'absorbance UV à 254 nm, traduisant l’élimination de matière organique dissoute par des mécanismes d'oxydation électrochimiques. Les coliformes fécaux sont réduits de trois unités logarithmiques.
Monitoring Change in Great Salt Lake
Authors: Naftz David , Angeroth Cory , Freeman Michael , Rowland Ryan , Carling Gregory
Published: August 2013

Great Salt Lake is the largest hypersaline lake in the Western Hemisphere and the fourth largest terminal lake in the world (Figure 1). The open water and adjacent wetlands of the Great Salt Lake ecosystem support millions of migratory waterfowl and shorebirds from throughout the Western Hemisphere [Aldrich and Paul, 2002]. In addition, the area is of important economic value: Brine shrimp (Artemia franciscana) residing in Great Salt Lake support an aquaculture shrimp cyst industry with annual revenues as high as $60 million.
Why freshwater organisms survived the asteroid that killed the dinosaurs
Authors: Schultz Colin
Published: August 2013

Roughly 65.5 million years ago, a massive asteroid smashed into present‐day Chicxulub, Mexico. The impact set fire to Earth's surface. Dust and ash darkened the sky, sending the planet into an “impact winter” that lasted months to years and caused the extinction of nonavian dinosaurs and half of ocean‐dwelling species. However, life in inland freshwater ecosystems largely escaped this fate. To try to understand why freshwater organisms held on while ocean life failed, Robertson et al. surveyed relevant research to understand how the mechanisms of extinction would have operated differently in the two environments.
Understanding the complexities of volcanoes that erupt just once
Authors: Schultz Colin
Published: August 2013

Most of the world's volcanoes erupt only once and, often, only for a short time—a few days to a couple of weeks. Because of the brevity of the eruptions and possibly because of a presumed docility, singly erupting volcanoes, known as monogenetic volcanoes, are not nearly as well studied as their polygenetic fellows. Traditionally, researchers have assumed that monogenetic volcanic eruptions are simple in their dynamics. A new investigation by Barde‐Cabusson et al., however, reveals that these volcanic eruptions can be highly complex, sometimes incorporating multiple phases and magma vents.
Warming climate increases rainfall extremes
Authors: Balcerak Ernie
Published: August 2013

In recent years there have been a number of prolonged heat waves and heavy rain events, and studies are showing that global climate warming is increasing the risk of extreme rainfall and drought. To add to the evidence linking climate warming and extreme precipitation and provide a regional as well as global perspective, Lau et al. analyzed projections from 14 different climate models that are part of the CMIP5 project, which is organized by the Intergovernmental Panel on Climate Change in preparation for its upcoming fifth assessment report.
Optically Transparent Antibacterial Films Capable of Healing Multiple Scratches
Authors: Wang Xu , Wang Yan , Bi Shuai , Wang Yongguo , Chen Xigao , Qiu Lingying , Sun Junqi
Published: August 2013

Optically transparent antibacterial films capable of healing scratches and restoring transparency are fabricated by exponential layer‐by‐layer assembly of branched polyethylenimine (bPEI)/poly(acrylic acid) (PAA) films and post‐diffusion of cetyltrimethylammonium bromide micelles encapsulated with antibacterial agent triclosan. The triclosan‐loaded bPEI/PAA transparent films can effectively inhibit the growth of gram‐positive and gram‐negative bacteria by the sustained release of triclosan molecules. Healing of multiple scratches on the triclosan‐loaded bPEI/PAA films can be conveniently achieved by immersing the films in water or spraying water on the damaged films, which also fully restores their transparency. The self‐healing ability of these transparent antibacterial films originates from the ability of bPEI and PAA to flow and recombine in the presence of water. The triclosan‐loaded bPEI/PAA films have satisfactory mechanical stability under ambient conditions, and thus show potential for application as transparent protective films with antibacterial properties.
Electrophilic Addition of Allylic Carbocations to 2‐Cyclopropylidene‐2‐arylethanols: A Strategy to 3‐Oxabicyclo[3.2.0]heptanes
Authors: Meng Bo , Huang Xian , Wu Luling
Published: August 2013

We have developed an electrophilic addition of allylic carbocations to 2‐cyclopropylidene‐2‐arylethanols constructing carbon‐carbon bonds with excellent regio‐ and stereoselectivities. The reaction affords 3‐oxabicyclo[3.2.0]heptanes in moderate to good yields via the electrophilic addition/ring‐opening/vinyl group shift/intramolecular cyclization sequence.

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Copper Oxide Nanoparticles Supported on Graphene Oxide‐ Catalyzed S‐Arylation: An Efficient and Ligand‐Free Synthesis of Aryl Sulfides
Authors: Kamal Ahmed , Srinivasulu Vunnam , Murty J. N. S. R. C , Shankaraiah Nagula , Nagesh Narayana , Srinivasa Reddy T. , Subba Rao A. V.
Published: August 2013

Copper oxide nanoparticles that are supported on graphene oxide as a catalytic system have been utilized for ligand‐free and solvent‐free CS cross‐coupling reactions with weak bases such as triethylamine. Symmetrical/unsymmetrical aryl sulfides have been synthesized by the coupling of different aryl halides with aromatic as well as aliphatic sulfides. Surprisingly, aryl chlorides also well reacted with different types of sulfides in the presence of dimethyl sulfoxide and cesium carbonate. Besides, this catalytic system is suitable for the synthesis of phenothiazines via cascade CS and CN cross‐coupling of ortho‐dihalides and ortho‐aminobenzothiazoles. In addition, this alternative approach is extremely useful for the synthesis of a variety of symmetrical diaryl sulfides by using thiourea as a sulfur source that is devoid of the foul smell of thiols. Indeed, the calculated E‐factor value of our present protocol is 2.52. Furthermore, this protocol is particularly attractive as an environmentally benign and practical method for the synthesis of different aryl sulfides. Moreover, the heterogeneous catalytic system described in this process represents not only a greener approach but retains its significant activity for up to six catalytic cycles.

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Atom‐Economic Synthesis of Optically Active Warfarin Anticoagulant over a Chiral MOF Organocatalyst
Authors: Shi Tao , Guo Zhiwei , Yu Huixian , Xie Jianwu , Zhong Yijun , Zhu Weidong
Published: August 2013

A novel chiral metal‐organic framework (MOF) organocatalyst has been developed, based on readily available MIL‐101 and the chiral primary diamine (1R,2R)‐1,2‐diphenylethylenediamine, by the post‐synthetic modification. Over the developed chiral heterogeneous catalyst the asymmetric synthesis of (S)‐warfarin with high enantioselectivity can be fulfilled on a gram‐scale (2.8 g) with excellent yield (92%) at low cost, making the synthesis method an ideal alternative to existing methods.

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Characterization of a French series of female cases of mesothelioma
Authors: Camiade Elodie , Gramond Celine , Jutand Marthe‐Aline , Audignon Sabyne , Rinaldo Mickael , Imbernon Ellen , Luce Daniele , Galateau‐Sallé Francoise , Astoul Philippe , Pairon Jean‐Claude , Brochard Patrick , Lacourt Aude
Published: August 2013

Background

More than 80% of mesothelioma cases in men are attributable to occupational asbestos exposure compared to only 40% in women. The objective of the study was to characterize a series of female pleural mesotheliomas according to known and suspected risk factors.

Methods

From the exhaustive recording of 318 female mesothelioma cases in the French National Mesothelioma Surveillance Program between 1998 and 2009, multiple correspondence analysis and hybrid clustering were performed to characterize these cases according to expert assessed occupational and non‐occupational exposure to asbestos and man‐made vitreous fibers, X‐ray exposure, and history of cancer and non‐malignant respiratory diseases.

Results

Four clusters were identified: (1) occupational exposure to asbestos and man‐made vitreous fibers (7.9% of subjects); (2) radiation exposure during radiotherapy (12.9%); (3) increased asbestos exposure (19.8%); and (4) “non‐exposure” characteristics (59.4%).

Conclusion

These results will allow hypotheses to be generated about associations between mesothelioma and non‐occupational asbestos exposure, X‐ray exposure and history of respiratory disease. Am. J. Ind. Med. 56:1307–1316, 2013. © 2013 Wiley Periodicals, Inc.
Therapeutic advances in muscular dystrophy
Authors: Leung Doris G. , Wagner Kathryn R.
Published: August 2013

The muscular dystrophies comprise a heterogeneous group of genetic disorders that produce progressive skeletal muscle weakness and wasting. There has been rapid growth and change in our understanding of these disorders in recent years, and advances in basic science are being translated into increasing numbers of clinical trials. This review will discuss therapeutic developments in 3 of the most common forms of muscular dystrophy: Duchenne muscular dystrophy, facioscapulohumeral muscular dystrophy, and myotonic dystrophy. Each of these disorders represents a different class of genetic disease (monogenic, epigenetic, and repeat expansion disorders), and the approach to therapy addresses the diverse and complex molecular mechanisms involved in these diseases. The large number of novel pharmacologic agents in development with good biologic rationale and strong proof of concept suggests there will be an improved quality of life for individuals with muscular dystrophy. Ann Neurol 2013;74:404–411
Crystallization and mechanical properties of isotactic polypropylene/calcium carbonate nanocomposites with a stratified distribution of calcium carbonate
Authors: Wang Ming , Lin Lu , Peng Qicai , Ou Wenyong , Li Huilin
Published: August 2013

Isotactic polypropylene (iPP)/calcium carbonate (CaCO3) nanocomposites with a stratified distribution of CaCO3 were prepared by two‐step molding. The iPP and CaCO3 nanoparticles were first mixed by a batch mixer and then compressed into thin layers. Thin iPP/CaCO3 layers alternating with thin neat iPP layers were finally compressed together to form the stratified samples. The transcrystals were observed in the stratified samples by polarized optical microscopy and scanning electron microscopy. The transcrystals grew from the surfaces of the filled layers and occupied most of the space in the neat iPP layers. The β‐form crystals were found in the stratified samples with thick transcrystalline layers, whereas the thickness of the transcrystalline layer was dependent on the content of CaCO3 nanoparticles and the cooling rate of the processing. The relative crystallinity index of the conventional samples first increased and then decreased with the content of CaCO3 nanoparticles. However, the relative crystallinity index of the stratified samples deceased slightly with the content of CaCO3 nanoparticles because of the stratified distribution of the CaCO3 nanoparticles. The stratified samples, except for the samples with high β‐form contents, became more brittle than the conventional samples because of the transcrystal formation in the iPP layers. The stratified samples with high β‐form contents showed much better mechanical properties than the conventional samples. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39632.
Design strategy for waterborne polyurethane with sodium sulfonate groups on the soft segments
Authors: Xia Jianrong , Xu Ying , Gong Cuiran , Gao Dongshou
Published: August 2013

The field of waterborne polyurethane (WPU) is gaining a great deal of momentum from both a commercial and academic sense because of increasing environmental and sustainable awareness. For polyurethane (PU) to be dispersible in water, the hydrophilic groups are very important in the design of the polymer chains. Herein, we present a design strategy for WPU having hydrophilic groups on the soft segments through the reaction of as‐synthesized OH‐terminated poly(ε‐caprolactone) diols containing a sodium sulfonate group with diisocyanate. A stable aqueous dispersion was then obtained, and this was followed by a subsequent chain extension reaction and emulsification. We found that the PU dispersion particles were a core–shell structure with a good particle size distribution, and the obtained films exhibited a low tensile strength and a high elongation at break. This approach provided valuable information for fundamental research in the production, modification, property enhancement, and new applications of these materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39657.
EPR Characterisation of the Ferrous Nitrosyl Complex Formed within the Oxygenase Domain of NO Synthase
Authors: Santolini Jérôme , Maréchal Amandine , Boussac Alain , Dorlet Pierre
Published: August 2013

Nitric oxide is produced in mammals by a class of enzymes called NO synthases (NOSs). It plays a central role in cellular signalling but also has deleterious effects, as it leads to the production of reactive oxygen and nitrogen species. NO forms a relatively stable adduct with ferrous haem proteins, which, in the case of NOS, is also a key catalytic intermediate. Despite extensive studies on the ferrous nitrosyl complex of other haem proteins (in particular myoglobin), little characterisation has been performed in the case of NOS. We report here a temperature‐dependent EPR study of the ferrous nitrosyl complex of the inducible mammalian NOS and the bacterial NOS‐like protein from Bacillus subtilis. The results show that the overall behaviours are similar to those observed for other haem proteins, but with distinct ratios between axial and rhombic forms in the case of the two NOS proteins. The distal environment appears to control the existence of the axial form and the evolution of the rhombic form.
Effect of Visible‐Light Exposure and Electrolyte Oxygen Content on the Capacitance of Sulfur‐Doped Carbon
Authors: Singh Kavindra , Seredych Mykola , Rodriguez Castellon Enrique , Bandosz Teresa J.
Published: August 2013

A high‐density and low‐surface‐area sulfur‐doped carbon material is tested as a supercapacitor in acidic and neutral media. The electrolytes that are used are either oxygenated or are exposed to atmospheric oxygen. The electrochemical capacitance is measured both in dark conditions and under simulated solar irradiation. The capacitance values are calculated after the first and the 20th cycles. After cycling, a significant increase in the capacitance is observed in both electrolytes, which is accompanied by clear oxidation of the carbon surface. Oxygen in the system and visible‐light irradiation considerably increases the performance. The enhancement in the capacitance is linked to the carbon texture and chemistry. Reduced sulfur that is incorporated into the carbon matrix promotes photogeneration of electrons and holes, and the latter have a positive effect on oxygen reduction reactions as the holes contribute to the oxidation of water and the formation of radicals. These processes lead to the oxidation of the carbon surface and the formation of pores in which charge can be stored. Changes in the chemistry of sulfur lead to a clear pseudocapacitive contribution, increasing the capacitance in the acidic medium.
Orthogonal Functionalisation of Upconverting NaYF4 Nanocrystals
Authors: Voliani Valerio , González‐Béjar María , Herranz‐Pérez Vicente , Duran‐Moreno Maria , Signore Giovanni , Garcia‐Verdugo Jose M. , Pérez‐Prieto Julia
Published: August 2013

A simple and straightforward method for the orthogonal functionalisation of upconverting NaYF4 nanocrystals (UCNCs)—doped withYb3+ and Er3+—based on N‐(3‐dimethylaminopropyl)‐N′‐ethylcarbodiimide/N‐hydroxysuccinimide (EDC/NHS) selective reactions between two dyes and two different reactive groups present at the periphery of the upconverting nanocrystals is reported. Organic‐soluble UCNCs of 10 and 50 nm in size are encapsulated efficiently in a 1:1 mixture of two commercial 3000 Da poly(ethylene glycol) derivatives with two different reactive groups (amino and carboxylic groups). The water‐dispersible UCNCs are non‐cytotoxic, stable in the physiological environment, and present free amine and carboxylic reactive groups on their periphery, allowing rapid, selective, and modular covalent conjugation to payloads through EDC/NHS reactions. PEG‐encapsulated UCNCs with and without covalent conjugation to payloads are characterised in vitro through spectroscopic, dynamic light scattering, and electron microscopy measurements. Living cell analyses coupled with TEM measurements confirm the uptake and low cytotoxicity of the coated UCNCs. They are linked covalently to two different dyes, internalised by living cells, and analysed by confocal microscopy. The related colocalisation measurements prove the reactivity of both amines and carboxylic acids on the periphery of the nanocrystals. This approach demonstrates that it is possible to produce water‐dispersible and cyto‐compatible dual‐functional UCNCs.
Custom‐Fit Ruthenium(II) Metallopeptides: A New Twist to DNA Binding With Coordination Compounds
Authors: Gamba Ilaria , Salvadó Iria , Rama Gustavo , Bertazzon Miriam , Sánchez Mateo I. , Sánchez‐Pedregal Víctor M. , Martínez‐Costas José , Brissos Rosa F. , Gamez Patrick , Mascareñas José L. , Vázquez López Miguel , Vázquez M. Eugenio
Published: August 2013

A new bipyridine building block has been used for the solid‐phase synthesis of dinuclear DNA‐binding ruthenium(II) metallopeptides. Detailed spectroscopic studies suggest that these compounds bind to the DNA by insertion into the DNA minor groove. Moreover, the potential of the solid‐phase peptide synthesis approach is demonstrated by the straightforward synthesis of an octaarginine derivative that shows effective cellular internalization and cytotoxicity linked with strong DNA interaction, as evidenced by steady‐state fluorescence spectroscopy and AFM studies.
Cooperative Use of VCD and XRD for the Determination of Tetrahydrobenzoisoquinolines Absolute Configuration: A Reliable Proof of Memory of Chirality and Retention of Configuration in Enediyne Rearrangements
Authors: Mondal Shovan , Naubron Jean‐Valère , Campolo Damien , Giorgi Michel , Bertrand Michéle P. , Nechab Malek
Published: August 2013

The absolute configurations (AC) of azaheterocylic compounds resulting from the cascade rearrangement of enediynes involving only light atoms were unambiguously assigned by the joint use of vibrational circular dichroism (VCD) and copper radiation single crystal X‐ray diffraction (XRD). These AC determinations proved that the rearrangements of enediynes proceeded with memory of chirality and retention of configuration. Chirality 25:832–839, 2013. © 2013 Wiley Periodicals, Inc.
The synthesis of novel zeolite Y nanoparticles using mesoporous silica with a temperature controlling method
Authors: Karami Davood , Mahinpey Nader
Published: August 2013

Porous nanoparticles aggregated from primary zeolite sodium‐form Y (NaY) nanocrystals were hydrothermally synthesised using porous precipitated silica as the silica source via a three‐stage temperature control strategy, using tetramethylammonium hydroxide (TMAOH) as an organic additive. The synthesised samples were characterised using powder X‐ray diffraction, energy dispersive X‐ray spectroscopy, nitrogen (N2) sorption, and particle size analysis. The results show that the zeolite aggregate particles with sizes of 150–600 nm were composed of highly crystalline zeolite NaY nanoparticles in the size range of 2–4 nm. The particle sizes of porous aggregates can be readily tuned by varying the additive amounts of the zeolite precursor gel without notably changing the sizes of the primary zeolite nanocrystals. The N2 sorption results show that the zeolite NaY aggregate particles had high microporosity with no clear mesoporosity. The zeolite particles exhibited very good resistance to mechanical conglomeration and remained intact after several months.
Changes in the availability of screening mammography, 2000–2010
Authors: Elkin Elena B. , Atoria Coral L. , Leoce Nicole , Bach Peter B. , Schrag Deborah
Published: August 2013

BACKGROUND

Rates of screening mammography have plateaued, and the number of mammography facilities has declined in the past decade. The objective of this study was to assess changes over time and geographic disparities in the availability of mammography services.

METHODS

Using information from the US Food and Drug Administration and the US Census, county‐level mammography capacity was defined as the number of mammography machines per 10,000 women aged ≥ 40 years. Cross‐sectional variation and longitudinal changes in capacity were examined in relation to county characteristics.

RESULTS

Between 2000 and 2010, the number of mammography facilities declined 10% from 9434 to 8469, the number of mammography machines declined 10% from 13,100 to 11,762, and the median county mammography capacity decreased nearly 20% from 1.77 to 1.42 machines per 10,000 women aged ≥ 40 years. In cross‐sectional analysis, counties with greater percentages of uninsured residents, less educated residents, greater population density, and higher managed care penetration had lower mammography capacity. Conversely, counties with more hospital beds per 100,000 population had higher capacity. High initial mammography capacity, growth in both the percentage of the population aged ≥ 65 years and the percentage living in poverty, and increased managed care penetration were all associated with a decrease in mammography capacity between 2000 and 2010. Only the percentage of rural residents was associated with an increase in capacity.

CONCLUSIONS

Geographic variation in mammography capacity and declines in capacity over time are associated with demographic, socioeconomic, and health care market characteristics. Maldistribution of mammography resources may explain geographic disparities in breast cancer screening rates. Cancer 2013;119:3847–3853. © 2013 American Cancer Society.
Myelosuppression after frontline fludarabine, cyclophosphamide, and rituximab in patients with chronic lymphocytic leukemia
Authors: Strati Paolo , Wierda William , Burger Jan , Ferrajoli Alessandra , Tam Constantine , Lerner Susan , Keating Michael J. , O'Brien Susan
Published: August 2013

BACKGROUND

The combination of fludarabine, cyclophosphamide, and rituximab (FCR) has produced improved response rates and a prolonged survival in patients with chronic lymphocytic leukemia (CLL). However, its therapeutic power is counterbalanced by significant hematologic toxicity. Persistent and new‐onset cytopenia after the completion of FCR raise concern about disease recurrence, the development of therapy‐related myeloid malignancies (TRMM), and infections.

METHODS

A total of 207 patients with CLL who achieved complete response, complete response with incomplete bone marrow recovery, or nodular partial remission were analyzed after frontline FCR therapy.

RESULTS

Three months after the completion of therapy, 35% of patients had developed grade 2 to 4 cytopenia (according to Common Terminology Criteria for Adverse Events [version 4.0]). Factors found to be associated with cytopenia at 3 months after therapy were older age, advanced Rai stage disease, and lower baseline blood counts. Moreover, patients with cytopenia were less likely to have completed 6 courses of therapy with FCR. At 6 months and 9 months after therapy, the prevalence of grade 2 to 4 cytopenia was 24% and 12%, respectively. No differences in progression‐free survival and overall survival were noted between cytopenic and noncytopenic patients or between patients with persistent and new‐onset cytopenia. The prevalence of TRMM was 2.3% and did not differ significantly between cytopenic and noncytopenic patients or between those with persistent and new‐onset disease. Late infections were more common in patients who were cytopenic at 9 months (38%) and were mostly bacterial (67%).

CONCLUSIONS

Cytopenia after the completion of therapy is a common complication of frontline FCR that improves over time, particularly for new‐onset cases. The presence of persistent cytopenia (lasting up to 9 months after the completion of therapy) should not raise concern about CLL recurrence of the development of TRMM, but should encourage surveillance for bacterial infections for an additional 9 months. Cancer 2013;119:3805–3811. © 2013 American Cancer Society.
Subtyping of pulmonary adenocarcinoma in cytologic specimens
Authors: Moreira Andre L.
Published: August 2013

The last World Health Organization classification recognized that pulmonary adenocarcinomas are heterogeneous and hinted at the possibility that different patterns of adenocarcinoma were associated with certain prognostic value. This concept was expanded and is now the basis for the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification.
Structural Characterization of Alumina‐Supported Rh Catalysts: Effects of Ceriation and Zirconiation by using Metal–Organic Precursors
Authors: Kroner Anna B. , Newton Mark A. , Tromp Moniek , Russell Andrea E. , Dent Andrew J. , Evans John
Published: August 2013

The effects of the addition of ceria and zirconia on the structural properties of supported rhodium catalysts (1.6 and 4 wt % Rh/γ‐Al2O3) are studied. Ceria and zirconia are deposited by using two preparation methods. Method I involves the deposition of ceria on γ‐Al2O3 from Ce(acac)3, and the rhodium metal is subsequently added, whereas method II is based on a controlled surface reaction technique, that is, the decomposition of metal–organic M(acac)x (in which M=Ce, x=3 and M=Zr, x=4) on Rh/γ‐Al2O3. The structures of the prepared catalyst materials are characterized ex situ by using N2 physisorption, transmission electron microscopy, high‐angle annular dark‐field scanning transmission election microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy (XPS), and X‐ray absorption fine structure spectroscopy (XAFS). All supported rhodium systems readily oxidize in air at room temperature. By using ceriated and zirconiated precursors, a larger rhodium‐based metallic core fraction is obtained in comparison to the undoped rhodium catalysts, suggesting that ceria and zirconia protect the rhodium particles against extensive oxidation. XPS results indicate that after the calcination and reduction treatments, a small amount of chlorine is retained on the support of all rhodium catalysts. EXAFS analysis shows significant RhCl interactions for Rh/Al2O3 and Rh/CeOx/Al2O3 (method I) catalysts. After reaction with H2/He in situ, for series of samples with 1.6 wt % Rh, the EXAFS first shell analysis affords a mean size of approximately 30 atoms. A broader spread is evident with a 4 wt % rhodium loading (ca. 30–110 atoms), with the incorporation of zirconium providing the largest particle sizes.
Synthesis of the Natural Product Building Block 5‐(3‐Bromophenyl)‐4‐hydroxy‐5‐methylhexan‐2‐one and its Chiral Characterization by Using Chiroptical Spectroscopy
Authors: De Gussem Ewoud , Cornelus Jelle , Pieters Sam , Van den Bossche Dries , Van der Eycken Johan , Herrebout Wouter , Bultinck Patrick
Published: August 2013

The absolute configuration of 5‐(3‐bromophenyl)‐4‐hydroxy‐5‐methylhexan‐2‐one, an intermediate in the synthesis of various natural products, is assigned by using vibrational circular dichroism (VCD), electronic circular dichroism (ECD), and optical rotatory dispersion (ORD). Experimental spectra were compared to density functional theory (DFT) calculations of the molecule with known configuration. These three techniques independently confirm that the absolute configuration is (S)‐5‐(3‐bromophenyl)‐4‐hydroxy‐5‐methylhexan‐2‐one, thus enabling us to assign the absolute configuration with high reliability. The reliability of the VCD analysis was assessed quantitatively by using the CompareVOA program. We found that, in cases in which the agreement between theory and experiment was very good, a value of 10 cm−1 for the triangular weighting function gave a more‐realistic discriminative power between enantiomers than the default value of 20 cm−1.
Generation and Dissociation of RCOOCaCl2− and other Carboxylate‐Substituted Superhalogens: CO2 Capture and Implications for Structure Analysis
Authors: Rodríguez‐Blanco Giovanny , Jobst Karl J. , Luider Theo M. , Terlouw Johan K. , Burgers Peter C.
Published: August 2013

Carboxylate‐substituted superhalogens of the type RCOOMX2− (M=Mg, Ca, Sr, Ba, Mn, Co, Ni, Zn; X=Cl, Br) are easily accessible in the gas phase by electrospray ionisation. Their collision‐induced dissociation (CID) characteristics have been probed by using ion‐trap and triple‐quadrupole mass analysers with particular emphasis on the behaviour of RCOOCaCl2−‐type ions. In the ion trap these appear to react readily with residual water to yield HOCaCl2− as the hydrolysis product. In the absence of water, a collision‐induced McLafferty‐type rearrangement takes over to produce HCaCl2− with the expulsion of an olefin and CO2. A brief computational analysis using the CBS‐QB3 model chemistry provides a satisfactory rationale for these observations. If complexed with MX2 (M=Mg, Ca, Sr, Ba), long‐chain unsaturated aliphatic carboxylate anions undergo various backbone cleavages upon collision. These lead to structure‐diagnostic olefin losses because the position of the double bonds remains intact. Such cleavages are absent in the bare ion RCOO−. The long‐chain ions RCOOMX2− also produce the intriguing species [CO2]MX2−.. These have been characterised by CID experiments, and theory indicates that they may be viewed as a CO2 molecule captured by the salt anion MX2−.. Finally, it is shown that the CID spectra of RCOOCaCl2− ions derived from all‐trans retinoic acid, a compound of current interest in biochemistry and medicine, show a unique structure‐diagnostic dissociation that may greatly aid its qualitative and quantitative analysis.
Can Semi‐empirical Calculations Help Solve Mass Spectrometry Problems? Protonation Sites and Proton Affinities of Amino Acids
Authors: Amorim Madeira Paulo J. , Vaz Pedro D. , Bettencourt da Silva R. J. N. , Florêncio M. Helena
Published: August 2013

Owing to the recent development of the PM6 and PM6‐DH+ semi‐empirical methodologies, which belong to the neglect of diatomic differential overlap (NDDO) family, it was decided to carry out a study to assess whether these inexpensive and fast methodologies could be used with confidence to help solve mass spectrometry problems. As such, a report on the feasibility of using semi‐empirical calculations to identify probable protonation sites in amino acids is presented. The optimised geometries obtained by the semi‐empirical calculations were compared to several structures reported in the literature (obtained through high‐level theoretical calculations) and reasonable agreement was found. The proton affinities derived from semi‐empirical calculations were also compared with experimental data and benchmarked as well with predicted values from the literature (also obtained through high‐level theoretical calculations). Semi‐empirical calculations accurately predicted the most probable protonation site for all amino acids considered; thus leading to results comparable to those obtained by high‐level calculations at an extremely low computational cost. Regarding the proton affinity estimates, deviations from the available experimental values are greater for the semi‐empirical proton affinities than for those observed for high‐level calculations. A statistical analysis of the data, at a confidence level of 99 %, also showed that the semi‐empirical proton affinities were different from experimental values and high‐level proton affinities were equivalent to experimental values. Nevertheless, the overall correlation of the semi‐empirical data with experimental values is, at least, satisfactory. We believe therefore that this paper shows that semi‐empirical methodologies, which are fast and inexpensive, can indeed solve mass spectrometry problems, or at least, facilitate a quicker path to the solution.
Identification of molecular and physiological responses to chronic environmental challenge in an invasive species: the Pacific oyster, Crassostrea gigas
Authors: Clark Melody S. , Thorne Michael A. S. , Amaral Ana , Vieira Florbela , Batista Frederico M. , Reis João , Power Deborah M.
Published: August 2013

Understanding the environmental responses of an invasive species is critical in predicting how ecosystem composition may be transformed in the future, especially under climate change. In this study, Crassostrea gigas, a species well adapted to the highly variable intertidal environment, was exposed to the chronic environmental challenges of temperature (19 and 24°C) and pH (ambient seawater and a reduction of 0.4 pH units) in an extended 3‐month laboratory‐based study. Physiological parameters were measured (condition index, shell growth, respiration, excretion rates, O:N ratios, and ability to repair shell damage) alongside molecular analyses. Temperature was by far the most important stressor, as demonstrated by reduced condition indexes and shell growth at 24°C, with relatively little effect detected for pH. Transcriptional profiling using candidate genes and SOLiD sequencing of mantle tissue revealed that classical “stress” genes, previously reported to be upregulated under acute temperature challenges, were not significantly expressed in any of the treatments, emphasizing the different response between acute and longer term chronic stress. The transcriptional profiling also elaborated on the cellular responses underpinning the physiological results, including the identification of the PI3K/AKT/mTOR pathway as a potentially novel marker for chronic environmental challenge. This study represents a first attempt to understand the energetic consequences of cumulative thermal stress on the intertidal C. gigas which could significantly impact on coastal ecosystem biodiversity and function in the future.
Energy intensity and global warming potential of corn grain ethanol production in Wisconsin (USA)
Authors: Kraatz Simone , Sinistore Julie C. , Reinemann Douglas J.
Published: August 2013

Increasing demand for renewable alternative fuels, such as ethanol, is driven by decreasing availability of fossil resources and increasing attention to climate change. Life cycle assessment (LCA) is the tool used to evaluate environmental impacts, such as energy intensity (EI) and global warming potential (GWP), from ethanol production, but the application of this tool varies greatly. The goals of this study were to enumerate the life cycle EI, net energy value (NEV), and GWP of corn grain ethanol production in Wisconsin, to explore ethanol production scenarios which differ at the treatment of the whole stillage (WS) coproduct, and to evaluate the various solutions to the multifunctionality problem which arises in LCA. In Scenario 1, all suggested solutions to the multifunctionality problem are considered by transforming WS into the animal feed dried distillers grains with solubles (DDGS). Scenario 2 avoids allocation using an integrated system which recycles the WS with an anaerobic biodigester and a combined heat and power (CHP) plant to provide electricity and steam to the ethanol refinery and returns the residue to the land as fertilizer. Based on the Scenario 1 analysis, we recommend the use of the subdivision (SD) solution to the multifunctionality problem because it enables clear comparisons between different ethanol production systems, it distinguishes between the environmental impacts from ethanol production and coproduct processing and it reduces the number of assumptions in the LCA calculations. From the comparison of both scenarios, we find that recycling the WS into electricity, heat, and fertilizer is the most environmentally beneficial coproduct use because it results in a 54% lower EI and a 67% lower GWP than the processing of WS into DDGS.
Common use of high doses of antipsychotic medications in older Asian patients with schizophrenia (2001–2009)
Authors: Xiang Yu‐Tao , Li Yan , Correll Christoph U. , Ungvari Gabor S. , Chiu Helen F.K. , Lai Kelly Y. C. , Tang Quan‐Sheng , Hao Wei , Si Tian‐Mei , Wang Chuan‐Yue , Lee Edwin H. M , He Yan‐Ling , Yang Shu‐Yu , Chong Mian‐Yoon , Kua Ee‐Heok , Fujii Senta , Sim Kang , Yong Michael K.H. , Trivedi Jitendra K. , Chung Eun‐Kee , Udomratn Pichet , Chee Kok‐Yoon , Sartorius Norman , Tan Chay‐Hoon , Shinfuku Naotaka
Published: August 2013

Objective

This study aimed to examine the use of high doses of antipsychotic medications (≥600 mg/day chlorpromazine equivalent) in older Asian patients with schizophrenia and its demographic and clinical correlates.

Method

Information on hospitalized patients with schizophrenia aged ≥50 years was extracted from the database of the Research on Asian Psychotropic Prescription Patterns study (2001–2009). Data on 2203 patients in six Asian countries and territories, including China, Hong Kong, Japan, Korea, Singapore and Taiwan, were analyzed. Socio‐demographic and clinical characteristics and antipsychotic prescriptions were recorded.

Results

The frequency for high‐dose antipsychotic medications was 36.0% overall, with 38.4% in 2001, 33.3% in 2004 and 36.0% in 2009. Multiple logistic regression analysis of the whole sample showed that compared to patients receiving low‐medium antipsychotic doses, those on high doses had a longer illness duration (odds ratio (OR): 2.0, 95% confidence interval (CI):1.2–3.3, p = 0.008), were more likely in the 50–59‐year group (OR: 0.95, 95% CI: 0.94–0.97, p < 0.001), more often had current positive (OR: 1.5, 95% CI: 1.2–1.8, p < 0.001) or negative symptoms (OR: 1.3, 95% CI: 1.03–1.6, p = 0.03), and more commonly received antipsychotic polypharmacy (OR: 5.3, 95% CI: 4.1–6.7, p < 0.001). Extrapyramidal symptoms (p = 0.25) and tardive dyskinesia (p = 0.92) were not more frequent in the high‐dose group.

Conclusions

High doses of antipsychotic medications were used in more than one third of older Asian patients with schizophrenia. The reasons for the frequent use of high antipsychotic doses in older Asian patients warrant further investigation. Copyright © 2013 John Wiley & Sons, Ltd.
Hydrogen Bonding Modules for Use in Supramolecular Polymers
Authors: Yang Si Kyung , Zimmerman Steven C.
Published: August 2013

Supramolecular polymer chemistry has emerged as a major research focus within polymer science, because of the potential to improve material properties, through the combination of noncovalent interactions and synthetic polymers. As a supramolecular handle, the most useful noncovalent interaction is hydrogen bonding, which has been used extensively, because of advantages such as synthetic accessibility, directionality, fidelity, and, most importantly, responsiveness to external stimuli. This review introduces recent advances in the development of hydrogen bonding modules that can be useful for creating a variety of supramolecular polymers. Furthermore, we present selected examples of hydrogen bonded supramolecular polymers from the literature, by dividing them into three categories: supramolecular polymers assembled from small molecules, and main‐chain and side‐chain supramolecular polymers.