bluuebunny/crossref_metadata_2025 huggingface dataset:
Incompatible Length Scales in Nanostructured Cu2O Solar Cells
Authors: Musselman Kevin P. , Marin Andrew , Schmidt‐Mende Lukas , MacManus‐Driscoll Judith L.
Published: March 2012

Electrodeposited Cu2O‐ZnO heterojunctions are promising low‐cost solar cells. While nanostructured architectures improve charge collection in these devices, low open‐circuit voltages result. Bilayer and nanowire Cu2O‐ZnO heterojunction architectures are systematically studied as a function of the Cu2O layer thickness, ZnO nanowire length, and nanowire seed layer. It is shown that a thick depletion layer exists in the Cu2O layer of bilayer devices, owing to the low carrier density of electrodeposited Cu2O, such that the predominant charge transport mechanisms in the Cu2O and ZnO are drift and diffusion, respectively. This suggests that the low open‐circuit voltage of the nanowire cells is due to an incompatibility between the nanostructure spacing required for good charge collection (<1 μm) and the heterojunction thickness necessary to form the full built‐in potential that inhibits recombination (>2 μm). The work shows the way to improve low‐cost Cu2O cells: increasing the carrier concentration or mobility in Cu2O synthesized at low temperatures.
Greener Electrochemical Synthesis of High Quality Graphene Nanosheets Directly from Pencil and its SPR Sensing Application
Authors: Singh Virendra V. , Gupta Garima , Batra Anirudh , Nigam Anil K. , Boopathi Mannan , Gutch Pranav K. , Tripathi Brajesh K. , Srivastava Anchal , Samuel Merwyn , Agarwal Gauri S. , Singh Beer , Vijayaraghavan Rajagopalan
Published: March 2012

A green, simple, and cost effective electrochemical method to synthesize pure graphene oxide (GO) and graphene nanosheets (GNs) using pencil in ionic liquid medium is reported. The morphology and microstructure of prepared GNs and GO are examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), X‐ray diffraction (XRD), and Raman spectroscopy; the experiments confirm the formation of high quality graphene. The synthesized GO is used for the real‐time and label‐free surface plasmon resonance (SPR) sensing of the biological warfare agent Salmonella typhi.
Palladium‐Catalyzed Intramolecular Annulation of 3‐[2‐(2‐Iodobenzylamino)aryl]‐N‐arylpropiolamides: Synthesis of 3‐[5H‐Dibenzo[b,e]azepin‐11(6H)‐ylidene]indolin‐2‐ones
Authors: Zou Tao , Zhang Xing‐Guo , Li Jin‐Heng , Deng Chen‐Liang , Tang Ri‐Yuan
Published: March 2012

A novel palladium‐catalyzed intramolecular tandem annulation method is presented for the synthesis of 3‐[5H‐dibenzo[b,e]azepin‐11(6H)‐ylidene]indolin‐2‐ones. This method allows the conversion of various 3‐[2‐(2‐iodobenzylamino)aryl]‐N‐arylpropiolamides to the corresponding 3‐[5H‐dibenzo[b,e]azepin‐11(6H)‐ylidene]indolin‐2‐ones through the diarylation of an alkyne.
Cobalt(II) Phthalocyanine‐Catalyzed Highly Chemoselective Reductive Amination of Carbonyl Compounds in a Green Solvent
Authors: Kumar Vishal , Sharma Upendra , Verma Praveen K. , Kumar Neeraj , Singh Bikram
Published: March 2012

Cobalt phthalocyanine has been employed for the highly chemoselective reductive amination of aldehydes and ketones in ethanol as a green solvent. A large range of functional groups such as nitro, acid, amide, ester, nitrile, halogen, lactone, methoxy, hydroxy, alkene, N‐benzyl, O‐benzyl and heterocyclic rings were well tolerated under the present reaction conditions.
Palladium‐Catalyzed Oxidative Intramolecular CC Bond Formation via Double sp2 CH Activation between the 2‐Position of Imidazoles and a Benzene Ring
Authors: Sun Manman , Wu Huandong , Zheng Junnan , Bao Weiliang
Published: March 2012

Oxidative intramolecular CC bond formation via double sp2 CH activation between the 2‐position of imidazoles and a benzene ring catalyzed by palladium(II) has been developed, which provides an atom‐economical, concise and efficient methodology to synthesize imidazole‐ or benzimidazole‐fused isoquinoline polyheteroaromatic compounds.
Cyclopropanation of Strained Alkenes by Palladium‐Catalyzed Reaction of 3‐Trimethylsilyl‐ or 3‐Pinacolatoboryl‐1‐arylallyl Acetates
Authors: Horino Yoshikazu , Homura Naoki , Inoue Kana , Yoshikawa Saori
Published: March 2012

The palladium‐catalyzed cyclopropanation of strained alkenes with 3‐trimethylsilyl‐ or 3‐pinacolatoboryl‐1‐arylallyl acetate derivatives is described. This reaction gives cyclopropanation products in good to high yields with a single diastereomer, and the key step is likely to involve the formation of a palladacyclobutene complex from the α‐trimethylsilyl‐ or α‐pinacolatoboryl‐σ‐allylpalladium complex.
Copper(I)‐Catalyzed Allylic Substitution of Silyl Nucleophiles through SiSi Bond Activation
Authors: Ito Hajime , Horita Yuko , Sawamura Masaya
Published: March 2012

We report the first copper(I)‐catalyzed reaction between a disilane and allylic carbonates to produce allylsilanes. The silyl nucleophilic substitution proceeded primarily in a SN2 fashion whereas SN2′ products were also obtained through σ‐π‐σ isomerization of the copper(III) intermediate depending on the substrate’s steric bulk.
Palladium‐Catalyzed, Highly Efficient, Regiocontrolled Arylation of Electron‐Rich Allylamines with Aryl Halides
Authors: Deng Yuheng , Jiang Zhen , Yao Min , Xu Dan , Zhang Lingjuan , Li Huanrong , Tang Weijun , Xu Lijin
Published: March 2012

The highly efficient and regioselective palladium‐catalyzed Heck coupling of aryl bromides with electron‐rich allylamine derivatives is described. It was found that the choice of solvent, olefin, ligand and additive had a fundamental influence on the regioselectivity and reactivity of the reaction. The combination of palladium acetate [Pd(OAc)2] and 1,3‐bis(diphenylphosphino)propane (dppp) in ethylene glycol (EG) constitutes a highly effective catalyst system for internal arylation of N‐Boc‐allylamine (tert‐butyl methyl allyliminodicarbonate) with aryl bromides to give good to excellent regioselectivities, while the catalyst system consisting of Pd(OAc)2, tetrabutylammonium bromide (TBAB) and 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO) additive allows for a variety of aryl bromides to react efficiently with N,N‐(Boc)2‐allylamine (di‐tert‐butyl allyliminodicarbonate) in water to exclusively afford the linear (E)‐allylamine products in high yields.
Transport in deformable hygroscopic porous media during microwave puffing
Authors: Rakesh Vineet , Datta Ashim K.
Published: March 2012

Microwave puffing is a process used to obtain low‐fat healthy foods by rapid heating of food products to develop high internal pressures in the material that cause significant structural changes. Two‐way coupling of complex multiphase transport and large deformations in the material, which is critical to simulate the puffing process accurately, was implemented. A porous media model that includes different phases, solid, liquid water, and gas, and incorporates pressure driven flow and evaporation was used to describe the transport processes in the material. Large deformations were included to model structural changes, with the material treated as hyperelastic. Arbitrary Lagrangian–Eulerian (ALE) framework was used. The model was validated using experimental temperature, moisture, and volume measurement and used to comprehensively understand the puffing process. Uncertainty analysis was carried out to estimate uncertainty in model prediction due to the choice of critical input parameters such as bulk modulus and permeabilities. © 2012 American Institute of Chemical Engineers AIChE J, 59: 33–45, 2013
Ammonia decomposition in catalytic membrane reactors: Simulation and experimental studies
Authors: Li Gang , Kanezashi Masakoto , Yoshioka Tomohisa , Tsuru Toshinori
Published: March 2012

Catalytic decomposition of NH3 with H2‐selective microporous silica membranes for COx‐free hydrogen production was studied theoretically and experimentally. The simulation study shows that NH3 conversion, H2 yield and H2 purity increase with the Damköhler number (Da), and their improvement is affected by the effect of H2 extraction as well as NH3 and N2 permeation through the membranes. The experimental study of NH3 decomposition was carried out in a bimodal catalytic membrane reactor (BCMR), consisting of a bimodal catalytic support and a H2‐selective silica layer. Catalytic membranes showed H2 permeances of 6.2–9.8 × 10−7 mol m−2 s−1 Pa−1, with H2/NH3 and H2/N2 permeance ratios of 110–200 and 200–700, respectively, at 773 K. The effect of operating conditions on membrane reactor performance with respect to NH3 conversion, H2 yield and H2 purity was investigated, and the results were in agreement with those calculated by the proposed simulation model. © 2012 American Institute of Chemical Engineers AIChE J, 59: 168–179, 2013
Effect of undernutrition on deciduous tooth emergence among Rajput children of Shimla District of Himachal Pradesh, India
Authors: Gaur Rajan , Kumar Pawan
Published: March 2012

This article examines the influence of nutritional status on the emergence of deciduous dentition in a cross‐sectional sample of 510 rural Rajput children from the Jubbal and Kotkhai Tehsils, Shimla District, Himachal Pradesh, India. The nutritional status of each child was evaluated using Z‐scores of height/supine length‐for‐age (HAZ), weight‐for‐age (WAZ), and weight‐for‐height (WHZ). The effects of sex and side on deciduous dental emergence were not statistically significant. Partial correlation indicates that the number of emerged teeth (T) was more strongly correlated with height than with other anthropometric variables. In most age groups, the stunted boys and girls (HAZ <−2) had fewer emerged teeth than nonstunted age peers (HAZ >−2). The mean T in underweight children was also less than that of the normal children, with a few exceptions. The stunted children have a significantly greater likelihood ofdelayed emergence of deciduous dentition. Measures of linear growth status are more closely related to dental development than measures of growth in mass. The findings indicate that even moderate undernutrition can delay deciduous tooth emergence. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.
Social tolerance in a despotic primate: Co‐feeding between consortship partners in rhesus macaques
Authors: Dubuc Constance , Hughes Kelly D. , Cascio Julie , Santos Laurie R.
Published: March 2012

Food sharing among nonkin—one of the most fascinating cooperative behaviors in humans—is not widespread in nonhuman primates. Over the past few years, a large body of work has investigated the contexts in which primates cooperate and share food with unrelated individuals. This work has successfully demonstrated that species‐specific differences in temperament constrain the extent to which food sharing emerges in experimental situations, with despotic species being less likely to share food than tolerant ones. However, little experimental work has examined the contexts that promote food sharing and cooperation within a species. Here, we examine whether one salient reproductive context—the consortship dyad—can allow the necessary social tolerance for co‐feeding to emerge in an extremely despotic species, the rhesus macaque (Macaca mulatta). We gave naturally formed male–female rhesus macaque pairs access to a monopolizable food site in the free‐ranging population at Cayo Santiago, Puerto Rico. Using this method, we were able to show that tolerated co‐feeding between unrelated adults can take place in this despotic species. Specifically, our results show that consort pairs co‐fed at the experimental food site more than nonconsort control pairs, leading females to obtain more food in this context. These results suggest that co‐feeding is possible even in the most despotic of primate species, but perhaps only in contexts that specifically promote the necessary social tolerance. Researchers might profit from exploring whether other kinds of within‐species contexts could also generate cooperative behaviors. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.
Totalsynthesen der Welwitindolinone mit Bicyclo[4.3.1]‐Kern
Authors: Huters Alexander D. , Styduhar Evan D. , Garg Neil K.
Published: March 2012

Die Welwitindolinone mit einem Bicyclo[4.3.1]‐Kern sind eine Klasse von Naturstoffen, die aufgrund ihrer faszinierenden Strukturen und ihrer vielversprechenden biologischen Eigenschaften bei Synthesechemikern großes Interesse hervorgerufen haben. Weltweit haben mehr als fünfzehn Laboratorien Fortschritte bei der Erforschung dieser empfindlichen Naturstoffe gemeldet. Hier werden aktuelle Untersuchungen zur Totalsynthese dieser anspruchsvollen Zielverbindungen dargelegt, und die beiden Synthesen von Welwitindolinonen mit einem Bicyclo[4.3.1]‐Kern, über die Rawal und Garg im Jahr 2011 berichteten, werden besprochen. Die beiden erst kürzlich vollendeten Ansätze beruhen auf der C4‐C11‐Bindungsbildung, wodurch das sterisch überladene bicyclische Gerüst dieser empfindlichen Naturstoffe zugänglich wird.
Relative contribution of small mountain ponds to regional richness of littoral macroinvertebrates and the implications for conservation
Authors: Martínez‐Sanz Carlos , Cenzano Cynthia S. S. , Fernández‐Aláez Margarita , García‐Criado Francisco
Published: March 2012

Biodiversity is a central concept in conservation programme design. Until recently, ponds were neglected habitats probably owing to their small size and to the ignorance of their real conservation value. The classical theory of species‐area relationship (SAR) might apparently support such a view by predicting low richness values in small habitat patches. SAR theory does not take into account the fact that groups of small habitat patches can significantly contribute to regional richness, regardless of their overall small area. This work intends to contribute to the SLOSS (single large or several small) debate with data on littoral macroinvertebrates from mountain ponds. Do groups of small ponds support communities with higher biodiversity than a single large lake?

Littoral macroinvertebrate richness, both local and regional, were measured in 17 ponds and one large lake from Sanabria Natural Park (NW Spain). In order to guarantee valid comparisons among systems, observed and estimated richness, as well as rarefaction methods were used.

Although local richness in the lake was much higher than in any single pond, regional richness of ponds widely exceeded the value measured in the lake regardless of their small overall area. Six to seven ponds were enough to obtain an accumulated average richness equivalent to that in the lake.

This pattern may be caused partly by increased habitat heterogeneity as proposed by the niche theory. Metacommunity theory might help to explain the high regional richness measured in the group of ponds in the study area.

Whatever the explanation, it is evident that groups of mountain ponds strongly contribute to regional richness, a conclusion that should be taken into account by management programmes. There is a gap in this respect in European legislation (the EC Habitats Directive and Water Framework Directive), which fails to include groups of ponds as an additional habitat category.

Copyright © 2012 John Wiley & Sons, Ltd.
Vascular Contrast Enhanced Micro‐CT Imaging of “Radiators” in the Brazilian Free‐Tailed Bat (Tadarida brasiliensis)
Authors: Reichard Jonathan D. , Kunz Thomas H. , Keller Charles , Prajapati Suresh I.
Published: March 2012

Thermal Infrared image of Brazilian free‐tailed bats. See Figure 1A in Reichard et al., on page 564, in this issue.
Charge Matching on Designing Neutral Cadmium–Lanthanide–Organic Open Frameworks for Luminescence Sensing
Authors: Yang Hui , Wang Fei , Tan Yan‐Xi , Kang Yao , Li Tie‐Hu , Zhang Jian
Published: March 2012

Through careful consideration of charge matching, a simple replacement of metal ion from Cd2+ to Ln3+ in a building unit successfully transforms an anionic microporous framework into a series of isostructural porous neutral heterometallic frameworks [Cd3Ln2(btc)4(H2O)6(dmf)4]⋅x(solvent) (1; Ln=Tb, Eu, Nd, Gd, Sm, dmf=N,N′‐dimethylformamide) by employing five different lanthanide ions. 1‐Tb and 1‐Eu exhibit interesting photoluminescent properties, and remarkably, 1‐Tb can act as a luminescent sensor to identify organic solvents and metal ions.
Formal Synthesis of (−)‐Englerin A and Cytotoxicity Studies of Truncated Englerins
Authors: Xu Jing , Caro‐Diaz Eduardo J. E. , Batova Ayse , Sullivan Steven D. E. , Theodorakis Emmanuel A.
Published: March 2012

An efficient formal synthesis of (−)‐englerin A (1) is reported. The target molecule is a recently isolated guaiane sesquiterpene that possesses highly potent and selective activity against renal cancer cell‐lines. Our enantioselective strategy involved the construction of the BC ring system of compound 1 through a RhII‐catalyzed [4+3] cycloaddition reaction followed by subsequent attachment of the A ring through an intramolecular aldol condensation reaction. As such, this strategy allows the synthesis of truncated englerins. Evaluation of these analogues with the A498 renal cancer cell‐line suggested that the A ring of englerin is crucial to its antiproliferative activity. Moreover, evaluation of these analogues led to the identification of potent growth‐inhibitors of CEM cells with GI50 values in the range 1–3 μM.
Image analysis in fluorescence microscopy: Bacterial dynamics as a case study
Authors: van Teeffelen Sven , Shaevitz Joshua W. , Gitai Zemer
Published: March 2012

Fluorescence microscopy is the primary tool for studying complex processes inside individual living cells. Technical advances in both molecular biology and microscopy have made it possible to image cells from many genetic and environmental backgrounds. These images contain a vast amount of information, which is often hidden behind various sources of noise, convoluted with other information and stochastic in nature. Accessing the desired biological information therefore requires new tools of computational image analysis and modeling. Here, we review some of the recent advances in computational analysis of images obtained from fluorescence microscopy, focusing on bacterial systems. We emphasize techniques that are readily available to molecular and cell biologists but also point out examples where problem‐specific image analyses are necessary. Thus, image analysis is not only a toolkit to be applied to new images but also an integral part of the design and implementation of a microscopy experiment.
Structure and transmembrane topology of slc11a1 TMD1–5 in lipid membranes
Authors: Li Jiantao , Wang Lingling , Wang Li , Li Fei
Published: March 2012

The importance of solute carrier family 11 (Slc11) in divalent metal‐ion transport has been well established. The core domains TMD1–5 and TMD6–10 of the proteins were modeled as a symmetric but inversely orientated arrangement with respect to membrane normal. In this article, the structures and transmembrane topologies of TMD1–5 of Slc11a1 incorporated with phospholipids 1‐palmitoyl‐2‐oleoyl‐ sn‐glycero‐3‐phosphocholine (POPC), 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐[phospho‐rac‐(1‐glycerol)] (sodium salt) (POPG), and POPC/POPG (3:1) were explored using circular dichroism, fluorescence, and attenuated total reflection Fourier transform infrared (ATR‐FTIR) spectroscopies. The segments TMD2–5 were inserted in lipid membranes mainly as an α‐helix with orientations of helices along membrane normal. The tilt angles of the helices were in an order of TMD3 > TMD4 > TMD2 > TMD5 in these membranes. In contrast, TMD1 was partly inserted in membranes, leaving partial segment at membrane surface. The amount of the lipid component with negatively charged headgroups had an effect on both the helicity and orientation of the transmembrane domains (TMDs). Nevertheless, the helices maintained similar topologies in various membranes. © 2011 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 98: 224–233, 2012.
Evaluation of five risk prediction models for elective abdominal aortic aneurysm repair using the UK National Vascular Database
Authors: Grant S W , Grayson A D , Mitchell D C , McCollum C N
Published: March 2012

Background

There is no consensus on the best risk prediction model for mortality following elective abdominal aortic aneurysm (AAA) repair. The objective was to evaluate the performance of five risk prediction models using the UK National Vascular Database (NVD).

Methods

Data on elective AAA repairs from the NVD between January 2008 and December 2010 were analysed. The models assessed were: Glasgow Aneurysm Score (GAS), Vascular Biochemical and Haematological Outcome Model (VBHOM), physiological component of the Vascular Physiological and Operative Severity Score for enUmeration of Mortality (V-POSSUM), Medicare and Vascular Governance North West (VGNW). Overall model discrimination and calibration in equally sized risk-group quintiles were assessed.

Results

The study cohort included 10 891 patients undergoing elective AAA repair (median age 74 years, 87·3 per cent men). The in-hospital mortality rates following endovascular and open repair were 1·3 and 4·7 per cent respectively (2·9 per cent overall). The Medicare and VGNW models both showed good discrimination (area under receiver operating characteristic (ROC) curve 0·71), whereas the GAS, VBHOM and V-POSSUM models showed poor discrimination (area under ROC curve 0·60, 0·61 and 0·62 respectively). The VGNW model was the only one to predict the overall mortality rate in the cohort (3·3 per cent predicted versus 2·9 per cent observed; P = 0·066). The VGNW model demonstrated good calibration, predicting risk accurately in four risk-group quintiles. The Medicare, V-POSSUM and VBHOM models accurately predicted risk in three, two and no risk-group quintiles respectively.

Conclusion

The Medicare and VGNW models contain similar risk factors and showed good discrimination when applied to the NVD. Both models would be suitable for risk prediction after elective AAA repair in the UK.
PKHD1 post‐transcriptionally modulated by miR‐365‐1 inhibits cell‐cell adhesion
Authors: Duan Jingjing , Huang Huizhe , Lv Xiaoyan , Wang Honglian , Tang Ziwei , Sun Huan , Li Qingwei , Ai Jianzhong , Tan Ruizhi , Liu Yuhang , Chen Mianzhi , Duan Weiwei , Wei Yuquan , Zhou Qin
Published: March 2012

Autosomal recessive polycystic kidney disease (ARPKD) is a severe inherited disorder with an incidence of 1/20 000 live births. Mutations of PKHD1 (polycystic kidney and hepatic disease gene 1) gene were identified to be responsible for ARPKD. However, the underlying molecular mechanisms remain largely unknown. MicroRNAs (miRNAs) are an abundant class of small RNAs with global effect on gene expression. Up to 30% of human protein coding genes may be regulated by miRNAs. However, to date, nothing is known regarding the role of miRNAs in PKHD1. In this study, we exploited bioinformatics to analyse the 3'UTR of PKHD1 gene and illustrated that the 3'UTR region of the gene is highly conserved in evolution. We identified about 35 candidate miRNAs within a 3738 bp window of the 3'UTR region. Of the 35 potential miRNAs, miR‐365‐1 emerged to post‐transcriptionally modulate the expression of PKHD1. Furthermore, we demonstrated that miR‐365‐1 modulated PKHD1 suppressed cell–cell adhesion in part through E‐cadherin. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of Temperature in Hydrocracking of Light Cycle Oil on a Noble Metal‐Supported Catalyst for Fuel Production
Authors: Gutiérrez A. , Arandes J. M. , Castaño P. , Olazar M. , Barona A. , Bilbao J.
Published: March 2012

The effect of temperature has been studied in hydrocracking of light cycle oil (LCO), byproduct of fluidized catalytic cracking (FCC) units on a bifunctional catalyst (Pt‐Pd/HY zeolite). The increase in both temperature and H2 partial pressure have an important attenuating effect on catalyst deactivation, given that they decrease sulfur equilibrium adsorption and enhance hydrocracking of coke precursors. Therefore, the catalyst maintains significant hydrodesulfurization and hydrocracking activity. As the temperature is increased, hydrocracking conversion and naphtha selectivity increase, although there is no significant dearomatization of the medium distillate fraction in the range of the studied experimental conditions. 400 °C is the more suitable temperature for obtaining a high yield of naphtha with a high content of i‐paraffins.
Single‐Jet Precipitation of Silver Nanocrystals in the Presence of Poly(acrylic) Acid
Authors: Mikami T. , Nagahori T. , Saito J. , Hirasawa I.
Published: March 2012

Precipitation of silver nanocrystals was carried out in a poly(acrylic) acid (PAA) solution by using a single‐jet crystallizer. The influence of the feeding rate, the injection position and the PAA dosage on the crystal size distribution (CSD) was clarified. The precipitated silver nanocrystals agglomerate with each other, forming an agglomerated microcrystal. In the presented case, smaller feeding rates caused smaller crystal sizes and narrower CSD widths. PAA, which is a water‐soluble polyelectrolyte, successfully inhibited agglomeration and crystal growth, and decreased the crystal size and the CSD width. Thus, this idea may also facilitate the production of other nano‐/microcrystalline particles.
Filter Cake Washing of Mesoporous Particles
Authors: Noerpel S. , Siauw V. , Nirschl H.
Published: March 2012

Particle synthesis in liquid phase usually requires a subsequent washing step in order to remove undesirable impurities such as unreacted educts, byproducts, solvents and salts. In particular, the washing of mesoporous particles is a challenging task due to large specific surface areas and void volumes. The filter cake washing of mesoporous SiO2 particles contaminated either with an adsorbing fluorescent dye or sodium sulfate is presented. The effects of wash liquid mass flow rate, mean particle size, and mean pore size on the wash efficiency were investigated. Especially the interaction between impurities and the solid surface, and thereby the initial impurity distribution within the filter cake, led to distinctive washing behaviors.
Mesoporous Au/TiO2 Nanocomposite Microspheres for Visible‐Light Photocatalysis
Authors: Wang Guannan , Wang Xiaofei , Liu Junfeng , Sun Xiaoming
Published: March 2012

Mesoporous Au/TiO2 nanocomposite microspheres have been synthesized by using a microemulsion‐based bottom‐up self‐assembly (EBS) process starting from monodisperse gold and titania nanocrystals as building blocks. The microspheres had large surface areas (above 270 m2 g−1) and open mesopores (about 5 nm), which led to the adsorption‐driven concentration of organic molecules in the vicinity of the microspheres. Au nanoparticles, which were stably confined within the microspheres, enhanced the absorption over the broad UV/Vis/NIR spectroscopic range, owing to their strong surface plasmon resonance (SPR); as a result, the Au nanoparticles promoted the visible‐light photo‐induced degradation of organic compounds.
Synthesis of a Hierarchical Three‐Component Nanocomposite Structure System with Enhanced Electrocatalytic and Photoelectrical Properties
Authors: Zhao Zhenlu , Zhang Guo , Sun Lei , Gao Ying , Yang Xiuyun , Li Yunhui
Published: March 2012

Effective control over the morphology and size of Pd/Pt nanoparticles is currently of immense interest because their electronic, optical, and catalytic properties are superior to pure platinum nanoparticles. However, control over the nanoparticle shape is still challenging. Therefore, a novel design and synthetic route needs to be developed to obtain a high‐performance catalyst. Herein, a hierarchical three‐component nanocomposite structure system (HTNSS) composed of graphene, TiO2, and Pd@Pt core–shell nanoparticles was designed and synthesized by a sequential strategy that focuses on constructing the monolithic structure rather than limited single‐component counterparts. The resulting composites were characterized by various techniques, which showed that the Pd@Pt core–shell nanoparticles were preferentially deposited on the peripheral interface of the graphene and TiO2 nanoparticles. The photoelectrical and catalytic performances were obviously improved relative to the commercially available E‐TEK Pt/C owing to their synergistic effect.
Oligonuclear Molecular Models of Intermetallic Phases: A Case Study on [Pd2Zn6Ga2(Cp*)5(CH3)3]
Authors: Bollermann Timo , Molon Mariusz , Gemel Christian , Freitag Kerstin , Seidel Rüdiger W. , von Hopffgarten Moritz , Jerabek Paul , Frenking Gernot , Fischer Roland A.
Published: March 2012

The synthesis, characterization, and theoretical investigation by means of quantum‐chemical calculations of an oligonuclear metal‐rich compound are presented. The reaction of homoleptic dinuclear palladium compound [Pd2(μ‐GaCp*)3(GaCp*)2] with ZnMe2 resulted in the formation of unprecedented ternary Pd/Ga/Zn compound [Pd2Zn6Ga2(Cp*)5(CH3)3] (1), which was analyzed by 1H and 13C NMR spectroscopy, MS, elemental analysis, and single‐crystal X‐ray diffraction. Compound 1 consisted of two Cs‐symmetric molecular isomers, as revealed by NMR spectroscopy, at which distinct site‐preferences related to the Ga and Zn positions were observed by quantum‐chemical calculations. Structural characterization of compound 1 showed significantly different coordination environments for both palladium centers. Whilst one Pd atom sat in the central of a bi‐capped trigonal prism, thereby resulting in a formal 18‐valence electron fragment, {Pd(ZnMe)2(ZnCp*)4(GaMe)}, the other Pd atom occupied one capping unit, thereby resulting in a highly unsaturated 12‐valence electron fragment, {Pd(GaCp*)}. The bonding situation, as determined by atoms‐in‐molecules analysis (AIM), NBO partial charges, and molecular orbital (MO) analysis, pointed out that significant PdPd interactions had a large stake in the stabilization of this unusual molecule. The characterization and quantum‐chemical calculations of compound 1 revealed distinct similarities to related M/Zn/Ga Hume–Rothery intermetallic solid‐state compounds, such as Ga/Zn‐exchange reactions, the site‐preferences of the Zn/Ga positions, and direct MM bonding, which contributes to the overall stability of the metal‐rich compound.
Branched Mesoporous Mn3O4 Nanorods: Facile Synthesis and Catalysis in the Degradation of Methylene Blue
Authors: Bai Zhongchao , Sun Bo , Fan Na , Ju Zhicheng , Li Menghua , Xu Liqiang , Qian Yitai
Published: March 2012

Branched MnOOH nanorods with diameters in the range of 50–150 nm and lengths of up to tens of micrometers were prepared by using potassium permanganate (KMnO4) and PEG 400 (PEG=polyethylene glycol) as starting materials through a simple hydrothermal process at 160 °C. After annealing at 300 °C under a N2 atmosphere for 5 h, MnOOH nanorods became gradually dehydrated and transformed into mesoporous Mn3O4 nanorods with a slight size‐shrinking. The as‐obtained mesoporous Mn3O4 nanorods had an average surface area of 32.88 m2 g−1 and a mean pore size of 3.7 nm. Through tuning the experimental parameters, such as the annealing atmosphere and temperature, β‐MnO2, Mn2O3, Mn3O4, MnO, and Mn5O8 were selectively produced. Among these structures, mesoporous Mn3O4 nanorods were efficient for the catalytic degradation of methylene blue (MB) in the presence of H2O2 at 80 °C.
Scandium(III)‐Zeolites as New Heterogeneous Catalysts for Imino‐Diels–Alder Reactions
Authors: Olmos Andrea , Louis Benoit , Pale Patrick
Published: March 2012

This study demonstrates the first zeolite‐catalyzed synthesis of piperidine derivatives, including peptidomimetics and indoloquinolizidine alkaloids. The approach developed utilizes a highly effective one‐pot reaction cascade, through imine formation and imino‐Diels–Alder reactions, promoted by scandium‐loaded zeolites as a heterogeneous catalyst. The methodology described benefits from very low catalyst loadings (≤5 mol % of ScIII), commercially and readily available starting materials, and mild reaction conditions. Furthermore, the ScIII‐zeolite catalyst can be readily reused more than 10 times without any loss in efficiency.
Characterisation of Solute Mobility in Hypercross‐Linked Resins in Solvents of Different Polarity: Two Promising Supports for Catalysis
Authors: Bortolus Marco , Centomo Paolo , Zecca Marco , Sassi Alessandro , Jeřábek Karel , Maniero Anna Lisa , Corain Benedetto
Published: March 2012

Two hypercross‐linked resins stemming from a gel‐type poly‐chloromethylated styrene‐divinylbenzene resin (GT) in beaded form are investigated with a combination of spectroscopic techniques (EPR and time‐domain (TD)‐NMR spectroscopy) to evaluate their use as supports for the development of operationally flexible heterogeneous metal catalysts, suitable to be employed in liquid and gas phase. The first resin (HGT) is the direct product of the hypercross‐linking reaction, whereas the second one (HGS) is the sulphonated analogue of HGT obtained by exchanging approximately 3 wt % of the chloromethyl groups with sulphonic groups. HGT and HGS absorb both polar and apolar solvents in the permanent nanoporosity created by the hypercross‐linking, and NMR data highlight that the pore size is not affected by the different properties of the investigated liquid media. The EPR analysis of the dry resins reveals that during the hypercross‐linking process paramagnetic species are formed in the HGT beads, which persist in the sulphonated resin. The mobility of solutes inside the polymers framework was investigated with EPR spectroscopy upon soaking the resins with solutions of two spin probes (2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) and 4‐hydroxy‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPOL)) in THF, toluene, n‐heptane and water. The EPR spectra show that, depending on the solvent, the two resins can act as sorbents, able to trap the solutes in the polymer framework, or as simple supports that allow free diffusion of the solutes. Our results suggest that HGT and HGS are promising supporting materials for metal catalysts, provided one chooses carefully the solvent to be employed for the catalysed reaction as this choice strongly affects the mobility of the substrates and, thus their effective reactivity.
Efficacy of positive contrast imaging techniques for molecular MRI of tumor angiogenesis
Authors: Wolters M. , Oostendorp M. , Coolen B. F. , Post M. J. , Janssen J. M. H. , Strijkers G. J. , Kooi M. E. , Nicolay K. , Backes W. H.
Published: March 2012

Superparamagnetic iron oxide particles (SPIOs) are promising contrast agents for molecular MRI. To improve the in vivo detection of iron‐based contrast media, positive contrast imaging techniques have been developed. Here, the efficacy of two positive contrast techniques, white marker and susceptibility gradient mapping (SGM), were evaluated for molecular MRI of tumor angiogenesis and compared with conventional negative contrast gradient echo (GE) imaging. In vitro, cylindrical phantoms containing varying iron oxide concentrations were used to measure the response of positive contrast techniques. In vivo, tumor bearing mice were used as a model for tumor angiogenesis. Mice were injected with unlabeled SPIOs (n = 5) or SPIOs labeled with cyclic NGR peptide (cNGR) (n = 5), which homes specifically to angiogenic microvessels. Pre‐ and post‐contrast GE and white marker images were acquired. Subsequently, SGM images and R2* maps were calculated. For image analysis, the contrast‐to‐noise ratio (CNR) and the percentage of enhanced voxels (EVs) in the tumor rim and core were calculated. In vitro, the linear increases in MRI signal response for increasing iron oxide concentration were much stronger for SGM than white marker. In vivo, the CNR of GE, white marker and SGM imaging was 5.7, 1.2 and 6.2, respectively, with equal acquisition times. Significant differences in the percentage of EVs between the tumor rim and core were found using R2* mapping, GE and SGM (p < 0.05). The two contrast agents had significantly different percentages of EVs by R2* mapping and SGM in the rim (p < 0.001). The in vivo efficacy of white marker and SGM was evaluated for molecular MRI relative to GE imaging and R2* mapping. Only SGM, and not white marker, can be used to transfer the negative contrast from targeted SPIOs in a positive contrast signal without loss of CNR. Copyright © 2012 John Wiley & Sons, Ltd.
A radiolabeled nonapeptide probe targeting PC‐3 cells and bone metastases of prostate cancer in mice
Authors: Qinghua Wu , Jianli Xu , Lu Liu , Zexuan Yang , Guansheng Tong , Hailin Gao , Jianwei Jiang
Published: March 2012

Previous investigations showed that interleukin‐11 (IL‐11) and the IL‐11 receptor (IL‐11R) are correlated with regulation of tumor progression and may play significant roles in bone metastases. The nonapeptide structure c(CGRRAGGSC) is a phage‐display‐selected IL‐11 mimic that binds to IL‐11R. The aim of this study was to synthesize radiolabeled c(CGRRAGGSC) and to investigate the possible interaction between this radioactive probe and an IL‐11R‐positive bone metastasis model of PC‐3 prostate cancer. The molecular probe 99mTc–DTPA–c(CGRRAGGSC) was radiolabeled with 99mTc using the diethylenetriaminepentaacetic acid (DTPA) chelate. Counterstaining was performed with LSS670, a near‐infrared dye. The binding sites of the molecular probe in PC‐3 cells were observed under a fluorescence microscope. The binding characteristics of the labeled probe were analyzed using radioreceptor analysis. Single photon emission tomography imaging and biodistribution of the probe were investigated using xenografts of PC‐3 cells into tibias of nude mice. The labeled product, 99mTc–DTPA–c(CGRRAGGSC), was obtained with high labeling efficiency, high radiochemical purity and good stability. The molecular probe was combined with the PC‐3 cell membrane and cytoplasm through fluorescence tracing. In the saturation and competitive inhibition experiments performed in vitro, the Kd value was 0.32 ± 0.02 n m and the Bmax value was 754 ± 34 fmol mg−1 pro. The probe exhibited a high tumor uptake in vivo. The radioactive molecular probe 99mTc–DTPA–c(CGRRAGGSC) may be used as a specific molecular imaging agent for detecting IL‐11R overexpression in tumors and bone metastasis, such as prostate cancers. Copyright © 2012 John Wiley & Sons, Ltd.
Congruence of primary brain tumor patient and caregiver symptom report
Authors: Armstrong Terri S. , Wefel Jeffrey S. , Gning Ibrahima , Acquaye Alvina , Vera‐Bolanos Elizabeth , Gilbert Mark R. , Cleeland Charles S. , Mendoza Tito
Published: March 2012

BACKGROUND:

Evaluating the severity of symptoms in patients with primary brain tumors (PBTs) is important in clinical care and research but may be difficult due to patient neurocognitive (NC) impairment. This study was conducted to evaluate the congruence of symptom reporting in patient and caregiver dyads, examining potential impact of NC impairment and Karnofsky performance status (KPS).

METHODS:

PBT patients undergoing NC testing and their caregivers were included in this study. These dyads (paired patient and caregiver group) completed the MD Anderson Symptom Inventory‐Brain Tumor Module prior to testing, and impairment was categorized based on NC test scores. Concordance and equivalency was then assessed using Bland‐Altman analysis and 2 one‐sided techniques.

RESULTS:

A total of 115 dyads participated. Median patient and caregiver age was 49 and 51 years, respectively, and 63% of patients were male (73% female caregivers). Most patients had a good KPS (≥90, 66%) but were classified as NC impaired (58%). Caregiver's report of patient symptoms are congruent to the self‐report of the patient. Equivalency between patient and caregiver report were found using prespecified confidence intervals. KPS group (good, ≥90; poor, ≤80) comparisons of equivalency indicated no significant differences in symptoms and interference reporting between dyads (good = 0.49, P > .05; and poor = 0.3, P > .05) overall, but there was a tendency for higher report by caregivers if the patients had a poor KPS.

CONCLUSIONS:

Caregivers of PBT patients have similar assessments of symptom severity (highly congruent) with patient self‐report regardless of NC function or KPS. These findings suggest that caregivers may serve as proxy report of symptoms for primary brain tumor patients. Cancer 2012. © 2012 American Cancer Society.
Insurance and inpatient care
Authors: Bradley Cathy J. , Dahman Bassam , Bear Harry D.
Published: March 2012

BACKGROUND:

Early research demonstrated that patients' length‐of‐stay and inpatient costs varied according to their health insurance status. The authors of the current report studied a population‐based sample of privately insured, Medicaid‐insured, and uninsured inpatients ages 21 to 64 years who underwent surgical resection for either nonsmall cell lung cancer (NSCLC) (n = 781) or colorectal cancer (CRC) (n = 8190) or who underwent mastectomy (n = 6201) to compare length of stay and inpatient costs by insurance status.

METHODS:

Data for this study were derived from all civilian, acute‐care hospitals in Virginia from 1999 to 2005. Hierarchical generalized linear models were used to estimate the relation between the explanatory variables and lengths of stay and costs. All analyses controlled for patient characteristics and hospital random effects.

RESULTS:

Medicaid‐insured patients with NSCLC had longer lengths of stay (39% or 2.64 days longer) and higher inpatient costs (20% or $2479 higher costs). Uninsured and Medicaid‐insured patients with CRC had longer lengths of stay and higher inpatient costs. In contrast, uninsured patients with breast cancer had 11% shorter lengths of stay and 12% lower inpatient costs than privately insured patients. Medicaid‐insured patients had 10% lower inpatient costs than privately insured patients. Differences were no longer statistically significant when reconstruction was added to the models.

CONCLUSIONS:

Health insurance affected the need for health care and the amount of health care received. Uninsured and Medicaid‐insured patients with lung cancer and colon cancer who underwent resection had longer lengths of stay and higher inpatient costs than privately insured patients, but they had shorter lengths of stay when reconstruction was not provided. Among the patients with breast cancer, patients and/or providers economized on discretionary procedures. Cancer 2012. © 2012 American Cancer Society.
From Single Molecule to Crystal: Mapping Out the Conformations of Tartaric Acids and Their Derivatives
Authors: Janiak Agnieszka , Rychlewska Urszula , Kwit Marcin , Stępień Urszula , Gawrońska Krystyna , Gawroński Jacek
Published: March 2012

Stereoisomers of one of the most important organic compounds, tartaric acid, optically active and meso as well as the ester or amide derivatives, can show diverse structures related to the rotation around the three carbon–carbon bonds. This study determines the controlling factors for conformational changes of these molecules in vacuo, in solution, and in the crystalline state using DFT calculations, spectroscopic measurements, and X‐ray diffraction. All structural variations can be logically accounted for by the possibility of formation and breaking of hydrogen bonds between the hydroxy or amide donors and oxygen acceptors, among these the hydrogen bonds that close five‐membered rings being the most stable. These findings are useful in designing molecular and crystal structures of highly polar, polyfunctional, chiral compounds.
Permethylated Salts and Radicals Derived from Azo peri‐Naphthalenes
Authors: Bohle D. Scott , Chua Zhijie , Johnstone Timothy , Moiseev Andrey G. , Perepichka Inna , Rosadiuk Kristopher A.
Published: March 2012

By careful choice of reaction conditions 1‐methylnaphtho[1,8‐de]‐1,2,3‐triazine and 1,3‐dimethylnaphtho[1,8‐de]‐1,2,3‐triazinium triflate are readily prepared by the alkylation of 1H‐naphtho[1,8‐de]‐1,2,3‐triazine. The electronic spectra for these bathochromically shifted dyes are reported for a range of solvents as are their vibrational spectra and theoretical structures from density functional theory, B3LYP/6‐311++G**. The 15N substitution into the middle nitrogen atom allows for the identification of strong azine bands in the IR and Raman spectra as well as in the 15N NMR spectrum. X‐ray crystallography is used to characterize the solid‐state structures of two of these new triazine derivatives and these structures are used to benchmark the theoretical and spectroscopic discussions. The corresponding 1,3‐dimethyltriazinium radical is prepared and characterized by cyclic voltammetry, spectroelectrochemistry, and EPR spectroscopy. Unlike the related transient 1,2,4‐triazene radicals, the 1,3‐dimethyl‐1,2,3‐naphthotriazyl radical is markedly more stable.
The reorganized brain: How treatment strategies for stroke and amblyopia can inform our knowledge of plasticity throughout the lifespan
Authors: Vida M.D. , Vingilis‐Jaremko L. , Butler B.E. , Gibson L.C. , Monteiro S.
Published: March 2012

Neural plasticity plays a crucial role in human development. During development, neural networks are shaped by experience‐dependent processes that selectively strengthen and prune connections so that those that remain match the environment and process it optimally. Over time, neural connections become more stable, forming widely distributed, interconnected networks involving balanced excitation and inhibition and structural stabilizers like myelin. It was long believed that the potential for organization or reorganization existed only during early development. However, the successful treatments for adults with stroke or amblyopia discussed in this issue suggest that the potential for significant reorganization persists well into adulthood. Thus, development can be thought of as the stabilization of connections to match the current environment but with considerable residual plasticity that can be revealed if there is a shift in the excitatory: inhibitory balance or the removal of the structural stabilizers. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 54:357‐368, 2012.
Sensitive periods for language and recovery from stroke: Conceptual and practical parallels
Authors: Zevin Jason D. , Datta Hia , Skipper Jeremy I.
Published: March 2012

In this review, we consider the literature on sensitive periods for language acquisition from the perspective of the stroke recovery literature treated in this Special Issue. Conceptually, the two areas of study are linked in a number of ways. For example, the fact that learning itself can set the stage for future failures to learn (in second language learning) or to remediate (as described in constraint therapy) is an important insight in both areas, as is the increasing awareness that limits on learning can be overcome by creating the appropriate environmental context. Similar practical issues, such as distinguishing native‐like language acquisition or recovery of function from compensatory mechanisms, arise in both areas as well. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 54:332‐342, 2012.
The effects of injury to dynamic neural networks in the mature and developing brain
Authors: Stiles Joan
Published: March 2012

This special section emphasizes three key factors relevant to understanding brain responses to injury. First, it is important to consider the impact of injury on brain networks rather then just the localized neuropathology. In contrast to older localizationist models, neural systems views emphasize that the effects of localized injury cascade through the neural system altering function at multiple levels. Thus, effective remediation must accommodate the multiple effects of brain injury. Second, the role of neural plasticity in the brain response to injury is critical. Rehabilitation implies that neural system is adaptive and capable of changing in response to input. Thus exploiting the brain's inherent plasticity is central to remediation. Finally, the timing of injury is an essential consideration. Adult injury disrupts stable neural systems and plasticity operates to regain functional balance. In contrast, early injury affects fundamental development processes and alters the emerging organization and functioning of neural systems. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 54:343‐349, 2012.