bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Advances in Organic One‐Dimensional Composite Materials: Design, Construction, and Photonic Elements for Information Processing
Authors: Yan Yongli , Zhang Chuang , Yao Jiannian , Zhao Yong Sheng 
Published: May 2013

AbstractMany recent activities in the use of one‐dimensional nanostructures as photonic elements for optical information processing are explained by huge advantages that photonic circuits possess over traditional silicon‐based electronic ones in bandwidth, heat dissipation, and resistance to electromagnetic wave interference. Organic materials are a promising candidate to support these optical‐related applications, as they combine the properties of plastics with broad spectral tunability, high optical cross‐section, easy fabrication, as well as low cost. Their outstanding compatibility allows organic composite structures which are made of two or more kinds of materials combined together, showing great superiority to single‐component materials due to the introduced interactions among multiple constituents, such as energy transfer, electron transfer, exciton coupling, etc. The easy processability of organic 1D crystalline heterostructures enables a fine topological control of both composition and geometry, which offsets the intrinsic deficiencies of individual material. At the same time, the strong exciton‐photon coupling and exciton‐exciton interaction impart the excellent confinement of photons in organic microstructures, thus light can be manipulated according to our intention to realize specific functions. These collective properties indicate a potential utility of organic heterogeneous material for miniaturized photonic circuitry. Herein, focus is given on recent advances of 1D organic crystalline heterostructures, with special emphasis on the novel design, controllable construction, diverse performance, as well as wide applications in isolated photonic elements for integration. It is proposed that the highly coupled, hybrid optical networks would be an important material basis towards the creation of on‐chip optical information processing.
Core–Shell Noble Metal Nanostructures Templated by Gold Nanorods
Authors: Hou Shuai , Hu Xiaona , Wen Tao , Liu Wenqi , Wu Xiaochun 
Published: May 2013

AbstractThe main research progress in core–shell noble metal nanostructures templated by gold nanorods (Au NRs) is summarized regarding synthesis, optical, and catalytic properties. Design and fabrication of core–shell hybrid nanostructures are demonstrated to be effective not only for optimizing and expanding intrinsic properties but also for creating novel localized surface plasmon enhanced optical and catalytic functionalities, thus providing great prospects in both fundamental research and potential applications.
Micro‐gels for impact protection
Authors: Zhou Chao , Wang Bo , Zhang Fengtao , Xu Kun , Han Changyu , Hu Hong , Liu Yanpin , Wang Pixin , Xin John H. 
Published: May 2013

ABSTRACTA novel kind of impact protective material, named as impact protective micro‐gel (IPM), was synthesized via a precipitation copolymerization of a compound containing boron and silanol. Diphenylmethane diisocyanate (MDI) was introduced as the chain extender to enhance its impact protective performance. Its rheological properties and morphology were investigated. Three‐dimensional (3D) spacer warp‐knitted fabrics were dip‐coated with the IPM made with and without use of MDI, and the impact protective performance of 3D finished fabrics was assessed by drop impact tests. The results show that the adjustment of the MDI content can adjust the real cross‐linking density of the IPM due to the entanglement of polymer chains, and an appropriate cross‐linking density can endow dilatant properties to the IPM samples. The results also show that the impact protective performance of 3D spacer fabrics finished with the IPM can be significantly improved. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2345–2351, 2013
Differential leaf‐litter processing by native (Gammarus pulex) and invasive (Dikerogammarus villosus) freshwater crustaceans under environmental extremes
Authors: Truhlar Allison M. , Dodd Jennifer A. , Aldridge David C. 
Published: May 2013

ABSTRACT

There is increasing interest in understanding the implications of biological invasions within the context of ecosystem functioning. Non‐native crustaceans are of particular interest within fresh waters because of their important contributions to leaf‐litter processing. The alien amphipod Dikerogammarus villosus is spreading rapidly through Europe where it has displaced native gammarids including Gammarus pulex. The resultant change in shredder communities has considerable implications for the dynamics of resource availability within invaded systems.
The invasive success of D. villosus has been attributed to many characteristics, including its ability to tolerate a wide range of environmental conditions and to exploit a wide feeding niche. These characteristics are thought to give D. villosus an advantage over native species, especially in habitats subject to changing environmental conditions.
The leaf (Salix alba) shredding efficiency, defined as the leaf mass consumed over the 4‐day experiment per amphipod‐day, was measured for D. villosus and G. pulex under extreme temperature and conductivity conditions, in single species and mixed species aquaria.
At high temperatures (25°C), D. villosus shredded significantly more leaves than size‐matched G. pulex. Conductivity extremes had no species effect; overall leaf‐shredding efficiency was significantly greater at low conductivity (250 μS cm‐1) than high conductivity (1870 μS cm‐1).
An inspection of daily leaf disc consumption found that the two species showed significantly different leaf consumption patterns, with D. villosus consuming more leaves earlier in the experiment.
These results suggest that D. villosus invasion could lead to ecosystem‐level changes in leaf processing, such as greater leaf processing earlier in autumn and at higher temperatures, which could alter nutrient dynamics and community assemblages within invaded systems. Such effects may not be reflected in biotic indices used to assess ecological status, as these indices do not currently distinguish between native and invasive species in the same family. Copyright © 2013 John Wiley & Sons, Ltd.
Facile Synthesis of Aluminum‐Based Metal–Organic Frameworks with Different Morphologies and Structures through an OH−‐Assisted Method
Authors: Lin Yichao , Kong Chunlong , Chen Liang 
Published: May 2013

AbstractWe report the facile synthesis of aluminum‐based metal–organic frameworks (MOFs) with different morphologies and structures by tuning the OH− content in the reaction solution. MIL‐96 crystals with dodecahedral and hexagonal column shapes were successfully synthesized by tuning the OH− ion content of the synthesis solution. When the OH− ion content was further increased, MIL‐110 with a nanorod morphology appeared as the product. For the first time, we obtained pure MIL‐96 and MIL‐110 under basic conditions directly by using the 1,3,5‐benzenetricarboxylic acid (btc) linker. All samples show significant thermal stability, with a decomposition temperature above 300 °C. We found that the gas adsorption properties of MIL‐96 were directly dominated by the crystal morphology. At 0.4 °C and 30 bar, the dodecahedral and hexagonal MIL‐96 samples can adsorb 9.3 and 6.5 mmol g−1 CO2, respectively, although they possess similar surface areas and identical crystalline structures. The MIL‐110 nanorod shows a CO2 adsorption capacity of up to 16 mmol g−1 under the same conditions.
Direct CH Bond Arylation of Indoles with Aryl Boronic Acids Catalyzed by Palladium Nanoparticles Encapsulated in Mesoporous Metal–Organic Framework
Authors: Huang Yuanbiao , Ma Tao , Huang Ping , Wu Dongshuang , Lin Zujin , Cao Rong 
Published: May 2013

AbstractHighly dispersed Pd nanoparticles encapsulated in the mesoporous metal–organic framework MIL‐101 demonstrated high activity and selectivity for the direct C2 arylation of various indoles with aryl boronic acids using O2 or 2,2,6,6‐tetramethylpiperidine N‐oxyradical as an external oxidant in acidic media under mild conditions. The green catalyst is easily recoverable and can be reused six times without leaching and loss of activity.
Phosphate‐Tether‐Mediated Ring‐Closing Metathesis for the Preparation of Complex 1,3‐anti‐Diol‐Containing Subunits
Authors: Chegondi Rambabu , Maitra Soma , Markley Jana L. , Hanson Paul R. 
Published: May 2013

AbstractAn array of examples of diastereoselective, phosphate‐tether‐mediated ring‐closing metathesis reactions, which highlight the importance of product ring size and substrate stereochemical compatibility, as well as complexity, is reported. Studies focus primarily on the formation of bicyclo[n.3.1]phosphates, involving the coupling of C2‐symmetric dienediol subunits with a variety of simple, as well as complex, alcohol partners.
Simultaneously Probing Two Ultrafast Condensed‐Phase Molecular Symmetry Breaking Events by Two‐Dimensional Infrared Spectroscopy
Authors: Yang Fan , Yu Pengyun , Zhao Juan , Wang Jianping 
Published: May 2013

AbstractIn condensed phases, a highly symmetric gas‐phase molecule lowers its symmetry under perturbation of the solvent, which is vital to a variety of structural chemistry related processes. However, the dynamical aspects of solvent‐mediated symmetry‐breaking events remain largely unknown. Herein, direct evidence for two types of solvent‐mediated symmetry‐breaking events that coexist on the picosecond timescale in a highly symmetric anion, namely, hexacyanocobaltate, is presented: 1) an equilibrium symmetry‐breaking event in which a solvent‐bound species having lowered symmetry undergoes a population exchange reaction with the symmetry‐retaining species; 2) a dynamic symmetry‐breaking event that is composed of many dynamic population‐exchange reactions under fluctuating solvent interactions. Ultrafast two‐dimensional infrared spectroscopy is used to simultaneously observe and dynamically characterize these two events. This work opens a new window into molecular symmetry and structural dynamics under equilibrium and non‐equilibrium conditions.
Polyethyleneimine‐Functionalized Polyamide Imide (Torlon) Hollow‐Fiber Sorbents for Post‐Combustion CO2 Capture
Authors: Li Fuyue Stephanie , Qiu Wulin , Lively Ryan P. , Lee Jong Suk , Rownaghi Ali A. , Koros William J. 
Published: May 2013

AbstractCarbon dioxide emitted from existing coal‐fired power plants is a major environmental concern due to possible links to global climate change. In this study, we expand upon previous work focused on aminosilane‐functionalized polymeric hollow‐fiber sorbents by introducing a new class of polyethyleneimine (PEI)‐functionalized polymeric hollow‐fiber sorbents for post‐combustion carbon dioxide capture. Different molecular weight PEIs (Mn≈600, 1800, 10 000, and 60 000) were studied as functional groups on polyamide imide (PAI, Torlon) hollow fibers. This imide ring‐opening modification introduces two amide functional groups and was confirmed by FTIR attenuated total reflectance spectroscopy. The carbon dioxide equilibrium sorption capacities of PEI‐functionalized Torlon materials were characterized by using both pressure decay and gravimetric sorption methods. For equivalent PEI concentrations, PAI functionalized with lower molecular weight PEI exhibited higher carbon dioxide capacities. The effect of water in the ring‐opening reaction was also studied. Up to a critical value, water in the reaction mixture enhanced the degree of functionalization of PEI to Torlon and resulted in higher carbon dioxide uptake within the functionalized material. Above the critical value, roughly 15 % w/w water, the fiber morphology was lost and the fiber was soluble in the solvent. PEI‐functionalized (Mn≈600) PAI under optimal reaction conditions was observed to have the highest CO2 uptake: 4.9 g CO2 per 100 g of polymer (1.1 mmol g−1) at 0.1 bar and 35 °C with dry 10 % CO2/90 % N2 feed for thermogravimetric analysis. By using water‐saturated feeds (10 % CO2/90 % N2 dry basis), CO2 sorption was observed to increase to 6.0 g CO2 per 100 g of sorbent (1.4 mmol g−1). This material also demonstrated stability in cyclic adsorption–desorption operations, even under wet conditions at which some highly effective sorbents tend to lose performance. Thus, PEI‐functionalized PAI fibers can be considered as promising material for post‐combustion CO2 capture.
Novel translinear differential implementation of rational functions with squared denominators
Authors: Carrasco‐Robles Manuel , Serrano Luis 
Published: May 2013

ABSTRACTThis paper presents a novel generic translinear differential output stage that is useful for the implementation of rational functions with a squared denominator. As a proof of concept, such output stage is used to implement the first derivative of a rational activation function. Simulated results are presented for an implementation on a 0.35 µm CMOS process showing an almost perfect fit with the theoretical expressions. Copyright © 2013 John Wiley & Sons, Ltd.
Synthesis and Pharmacological Evaluation of New Pyridazin‐Based Thioderivatives as Formyl Peptide Receptor (FPR) Agonists
Authors: Crocetti Letizia , Vergelli Claudia , Cilibrizzi Agostino , Graziano Alessia , Khlebnikov Andrei I. , Kirpotina Liliya N. , Schepetkin Igor A. , Quinn Mark T. , Giovannoni Maria Paola 
Published: May 2013

Abstract

Preclinical Research

A new series of pyridazinone‐based thioderivatives and pyridazine analogs was synthesized and tested for their ability to bind to the three human formyl peptide receptor (FPR) isoforms (FPR1, FPR2, and FPR3) and to activate intracellular calcium mobilization and chemotaxis in human neutrophils. Among the pyridazin‐3(2H)‐one derivatives tested, analogs 8b and 8c were mixed FPR1/FPR2 agonists, with median effective concentration values in the micromolar range, and were able to activate chemotaxis and Ca2+ flux in human neutrophils in the low micromolar range. Molecular docking studies showed that interaction of a ligand with Arg205 of FPR1 is important for FPR1 agonist activity. For FPR2, differences in activity between oxygen‐containing compounds and their thio‐analogs were due to steric bulkiness of sulfur‐containing groups.
Developmental trajectories and breakdown in F1 interpopulation hybrids of Tribolium castaneum
Authors: Drury Douglas W. , Ehmke Ross C. , Jideonwo Victoria N. , Wade Michael J. 
Published: May 2013

AbstractWhen hybrid inviability is an indirect by‐product of local adaptation, we expect its degree of severity between pairs of populations to vary and to be sensitive to the environment. While complete reciprocal hybrid inviability is the outcome of the gradual process of local adaptation, it is not representative of the process of accumulation of incompatibility. In the flour beetle, Tribolium castaneum, some pairs of populations exhibit complete, reciprocal F1 hybrid incompatibility while other pairs are fully or partially compatible. We characterize this naturally occurring variation in the degree and timing of expression of the hybrid incompatible phenotype to better understand the number of genes or developmental processes contributing to speciation. We assessed the morphological and developmental variation in four Tribolium castaneum populations and their 12 possible F1 hybrids at each life‐history stage from egg to adult. We find that the rate of hybrid larval development is affected in all interpopulation crosses, including those eventually producing viable, fertile adults. Hybrid incompatibility manifests early in development as changes in the duration of instars and diminished success in the transition between instars are relative to the parent populations. Parent populations with similar developmental profiles may produce hybrids with disrupted development. The degree and timing of expression of hybrid inviability depends upon populations crossed, direction of the cross, and environment in which hybrids are raised. Our findings suggest that the coordinated expression of genes involved in transitional periods of development is the underlying cause of hybrid incompatibility in this species.
On detecting non‐monotonic trends in environmental time series: a fusion of local regression and bootstrap
Authors: Lyubchich Vyacheslav , Gel Yulia R. , El‐Shaarawi Abdel 
Published: May 2013

AbstractIn this paper, we propose a new testing procedure for detecting smooth (non)monotonic trends embedded into a linear noise that possibly does not degenerate to a finite‐dimensional representation or into a conditionally heteroscedastic (autoregressive conditionally heteroscedastic/generalized autoregressive conditionally heteroscedastic (ARCH/GARCH)) noise. The proposed nonparametric trend test is local regression‐based, and we develop a flexible and computationally efficient hybrid bootstrap procedure to approximate its finite sample behavior. Because the proposed trend test does not assume prior knowledge on the dependence structure and probability distribution of the observed process, the new testing procedure is fully data‐driven and robust to misspecification of dependence structure and distributional assumptions, which is of particular importance for noisy environmental measurements. Moreover, because the proposed methodology allows to test for monotonic versus non‐monotonic trends and hence, to assess existence of extremums in the hypothesized trend function, the developed approach may be also employed for preliminary detection of regime shifts and change points in the observed environmental data series. Our simulation studies indicate competitive performance of the proposed nonparametric procedure for detection of (non)monotonic trends against conventional trend tests. Copyright © 2013 John Wiley & Sons, Ltd.
Use of a watershed hydrologic model to estimate interbasin groundwater flow in a Costa Rican rainforest
Authors: Zanon Carlo , Genereux David P. , Oberbauer Steven F. 
Published: May 2013

AbstractThe watershed hydrologic model TOPMODEL was used to estimate interbasin groundwater flow (IGF) into a small lowland rainforest watershed in Costa Rica. IGF is a common hydrological process but often difficult to quantify. Four‐year simulations (2006–2009) using three different model approaches gave estimates of IGF that were very similar to each other (10.1, 10.2, and 9.8 m/year) and to an earlier estimate (10.0 m/year) based on 1998–2002 data from a budget study that did not use a hydrologic simulation model, providing confidence in the new estimates and suggesting each of the three model approaches is viable. Results show no significant temporal variation in IGF during 2006–2009 (or between this period and the earlier study from 1998–2002). Simulations of the 16 consecutive 3‐month periods in 2006–2009 gave 16 values of IGF rate with a mean (10.1 m/year, standard deviation = 0.6 m/year) very similar to the estimates above from the 4‐year simulations. This suggests the modified version of TOPMODEL can be used to model stream discharge and estimate IGF for sub‐annual time periods during which change in water storage is not necessarily equal to zero. Thus, simple watershed models may be used to estimate IGF based on even relatively short calibration periods, making such models useful tools in the study of this widespread hydrological process that affects water and chemical fluxes and budgets but is often difficult and costly to quantify. Copyright © 2013 John Wiley & Sons, Ltd.
The role of the α7 subunit of the nicotinic acetylcholine receptor on motor coordination in mice treated with methyllycaconitine and anabasine
Authors: Welch K. D. , Pfister J. A. , Gardner D. R. , Green B. T. , Panter K. E. 
Published: May 2013

ABSTRACTThe adverse effects of methyllycaconitine (MLA) have been attributed to competitive antagonism of nicotinic acetylcholine receptors (nAChR). Research has indicated a correlation between the LD50 of MLA and the amount of α7 nAChR in various mouse strains, suggesting that mice with more α7 nAChR require more MLA to be poisoned. However, recent research demonstrated that there was no difference in the acute lethality (LD50) to MLA in mice lacking the α7 nAChR subunit compared with wild‐type mice. The objective of this study was to determine if the α7 nAChR subunit plays a role in motor coordination deficiencies that result from exposure to nAChR antagonists and agonists. We compared the motor function and coordination in wild‐type mice to mice lacking the α7 subunit of the nAChR, after treating them with a non‐lethal dose of MLA or anabasine, using the following tests: balance beam, grip strength, rotarod, open field and tremor monitor. Analysis of the data indicated that overall there was no difference between the wild‐type and knockout mice (P = 0.39 for grip strength; P = 0.21 for rotarod; P = 0.41 for balance beam; P = 0.22 for open field; and P = 0.62 for tremors). Thus results from this study suggest that α7 nAChR does not play an integral role in the acute effects of MLA or anabasine on motor function/coordination. Consequently other subunits of nAChRs found in the neuromuscular junction are likely the primary target for MLA and anabasine resulting in motor coordination deficiencies and acute toxicosis. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Sclerostin antibody stimulates bone regeneration after experimental periodontitis
Authors: Taut Andrei D , Jin Qiming , Chung Jong-Hyuk , Galindo-Moreno Pablo , Yi Erica S , Sugai James V , Ke Hua Z , Liu Min , Giannobile William V 
Published: May 2013

ABSTRACT

The reconstruction of large osseous defects due to periodontitis is a challenge in regenerative therapy. Sclerostin, secreted by osteocytes, is a key physiological inhibitor of osteogenesis. Pharmacologic inhibition of sclerostin using sclerostin-neutralizing monoclonal antibody (Scl-Ab) thus increases bone formation, bone mass and bone strength in models of osteopenia and fracture repair. This study assessed the therapeutic potential of Scl-Ab to stimulate alveolar bone regeneration following experimental periodontitis (EP). Ligature-induced EP was induced in rats to generate localized alveolar bone defects. Following 4 weeks of disease induction, Scl-Ab (+EP) or vehicle (+/− EP) were systemically delivered, twice weekly for up to 6 wks to determine the ability of Scl-Ab to regenerate bone around tooth-supporting osseous defects. 3 and 6 wks after the initiation of Scl-Ab or vehicle treatment, femur and maxillary jawbones were harvested for histology, histomorphometry, and micro-computed tomography (micro-CT) of linear alveolar bone loss (ABL) and volumetric measures of bone support, including bone volume fraction (BVF) and tissue mineral density (TMD). Serum was analyzed to examine bone turnover markers during disease and regenerative therapy. Vehicle + EP animals exhibited maxillary bone loss (BVF, TMD and ABL) at ligature removal and thereafter. 6 weeks of Scl-Ab significantly improved maxillary bone healing, as measured by BVF, TMD and ABL, when compared to vehicle + EP. After 6 weeks of treatment, BVF and TMD values in the Scl-Ab + EP group were similar to those of healthy controls. Serum analysis demonstrated higher levels of bone formation markers osteocalcin and PINP in Scl-Ab treatment groups. Scl-Ab restored alveolar bone mass following experimental periodontitis. These findings warrant further exploration of Scl-Ab therapy in this and other oral bone defect disease scenarios. © 2013 American Society for Bone and Mineral Research.