bluuebunny/crossref_metadata_2025 huggingface dataset:
The formation of stereocomplex in asymmetric blends of PLLGA and PDLA and the effect of stereocomplex on PLLGA crystallization
Authors: Dong Jun , Wang Bing , Xiong Zuochun , Bai Wei , Xiong Chengdong
Published: June 2014

The isothermal and non‐isothermal crystallization behaviors of asymmetric poly(L‐ lactic acid‐ co‐ glycolic acid) (PLLGA)/poly(D‐lactic acid) (PDLA) blends was investigated at PDLA loadings of up to 10 wt%. A simple solvent‐casting procedure, was developed for the preparation of PLLGA/PDLA stereocomplex crystallites dispersed in a PLLGA matrix. The formation of stereocomplexes in the PLLGA matrix was verified by differential scanning calorimetry (DSC) and X‐ray diffraction (XRD). Non‐isothermal crystallization measurement demonstrated that the addition of PDLA significantly accelerates the crystallization of PLLGA. Subsequent assessment of the influence of PDLA content on the isothermal crystallization kinetics of PLLGA by the Avrami equation confirmed that the crystallization rate of PLLGA is enhanced by the addition of PDLA contents, with a reduction in the half crystallization time (t1/2) and increase in the crystallization rate constant (k) values. A PDLA content of 1–7 wt% was found to particularly enhance the crystallization rate of PLLGA, from which it is inferred that the PLLGA/PDLA stereocomplex crystals act as effective nucleus to enhance the crystallization of PLLGA.
Hollow Nanospheres Constructed by CoS2 Nanosheets with a Nitrogen‐Doped‐Carbon Coating for Energy‐Storage and Photocatalysis
Authors: Peng Shengjie , Li Linlin , Mhaisalkar Subodh G. , Srinivasan Madhavi , Ramakrishna Seeram , Yan Qingyu
Published: June 2014

Hierarchical CoS2 hollow nanospheres (HSs) with a nitrogen‐doped‐carbon coating (NC@CoS2) are fabricated by a simple solution method. The uniform 300 nm‐sized NC@CoS2 HSs are composed of ultrathin nanosheet subunits with a thickness of around 2 nm. It was found that polyvinylpyrrolidone and ethylenediamine not only controlled the morphology of the products, but also provided the sources of nitrogen‐doped carbon. Benefiting from their unique structural characteristics, hierarchical NC@CoS2 HSs can be applied in lithium‐ion batteries, supercapacitors, and photocatalysis. When evaluated as an electrode material, NC@CoS2 with a coating of optimal thickness showed a high lithium‐storage capability with a good cycling stability. Moreover, NC@CoS2 had a remarkable supercapacitive performance and photocatalytic activity. The attractive electrochemical and photocatalytic performances were attributed to the overall structural features of the NC@CoS2 hollow spheres: the N‐doped‐carbon (NC) coating, hollow interior, and ultrathin nanosheets.
Direct Synthesis of Fe3C‐Functionalized Graphene by High Temperature Autoclave Pyrolysis for Oxygen Reduction
Authors: Hu Yang , Jensen Jens Oluf , Zhang Wei , Huang Yunjie , Cleemann Lars N. , Xing Wei , Bjerrum Niels J. , Li Qingfeng
Published: June 2014

We present a novel approach to direct fabrication of few‐layer graphene sheets with encapsulated Fe3C nanoparticles from pyrolysis of volatile non‐graphitic precursors without any substrate. This one‐step autoclave approach is facile and potentially scalable for production. Tested as an electrocatalyst, the graphene‐based composite exhibited excellent catalytic activity towards the oxygen reduction reaction in alkaline solution with an onset potential of ca. 1.05 V (vs. the reversible hydrogen electrode) and a half‐wave potential of 0.83 V, which is comparable to the commercial Pt/C catalyst.
Towards realistic connectivity restoration in partitioned mobile sensor networks
Authors: Senturk I.F. , Akkaya K. , Janansefat S.
Published: June 2014

The connectivity of a disjoint mobile sensor network can be restored by moving a set of nodes to certain destinations. However, all of the existing works have assumed that the selected destinations can be reached via direct path movement, which may not be the case in real‐world applications because of obstacles or terrain elevation. In addition, even if direct path movement is successful, optimal energy efficiency cannot be attained by neglecting the elevation or friction of the terrain when determining the movement path of the nodes. Thus, in the recovery efforts, terrain type, elevation, obstacles, and possible localization errors should be considered in order to guarantee the connectivity restoration while minimizing the recovery cost in terms of energy. In this paper, we pick two sample distributed and centralized connectivity restoration approaches from the literature to show that these approaches fail to restore connectivity in many cases due to the lack of considering realistic issues. These approaches are re‐designed in order to determine movement trajectory based on a path planning algorithm, which considers the risk and elevation of the terrain sections. Experiment results reveal several issues regarding the performance in terms of energy consumption and recovery delay. Copyright © 2014 John Wiley & Sons, Ltd.
Modulating the MII/Pyrimidine‐4,6‐dicarboxylato System by Metal, Solvent and Temperature Variation
Authors: Cepeda Javier , Pérez‐Yáñez Sonia
Published: June 2014

We report herein the synthesis and physicochemical characterisation of seven new compounds employing divalent metal ions and pyrimidine‐4,6‐dicarboxylato ligand (pmdc): {[Cd(μ‐pmdc)(H2O)3]·2H2O}n (1), [Cd(phen)(μ3‐pmdc)]n (2), [Cd(μ5‐pmdc)]n (3), {[Ca(μ3‐pmdc)(H2O)3]·H2O}n (4), {[Mn(μ‐pmdc)(form)(H2O)]·2H2O}n (5), [Cu(μ‐pmdc)(DMSO)2]n (6), and {[Zn(μ‐pmdc)(DMF)(H2O)]·DMF}n (7) (where phen = 1,10‐phenanthroline, form = formamide, DMSO = dimethyl sulfoxide, DMF = dimethylformamide). These compounds are the result of three different approaches that share a common aim: to replace/eliminate coordination solvent molecules to force unusual coordination modes of pmdc that render MII‐pmdc polymers with different structural motifs. To this end, we have employed either metal ions that permit high coordination numbers or organic aprotic solvents that can also act as terminal ligands, while different thermal treatments have been applied to both the reaction mixtures as well as solid compounds. The crystal structure of compound 1 contains zig‐zag polymeric chains in which mer‐[Cd(H2O)3]2+ units are sequentially joined by means of bis‐chelating pmdc ligands. Compound 2 is made up of stacked neutral layers that are built up from the fusion of two independent centrosymmetric [Cd2(phen)2(μ3‐pmdc)2] dinuclear units. Hydrothermal treatment at higher temperature led to compound 3, which presents a three‐dimensional framework in which the pmdc ligand exhibits an unprecedented μ5‐κ2N,O:κ2N′,O′:κO′:κO″:κO″′ coordination mode. Moreover, thermogravimetric and thermodiffractometric analyses of 1 have also provided access to an alternative route to obtain higher dimensional frameworks with crystal structures that differ from those crystallised in dissolution. Compound 4 consists of neutral 2D [Ca(μ3‐pmdc)(H2O)3] sheets that are formed by the junction of calcium‐pmdc chains through carboxylate oxygen bridges, exhibiting a herringbone pattern. On the other hand, formamide, dimethyl sulfoxide, and dimethylformamide have been employed in compounds 5–7 to evaluate their effect on the resulting coordination polymer. A common feature in these compounds is the one‐dimensional structure displayed and the fact that at least one solvent molecule is coordinated to the metal atoms. Whereas the manganese and zinc compounds exhibit corrugated MII‐pmdc chains, the copper compound adopts the more typical planar arrangement. The disposition of the chains of compounds 5–7 has been rationalised on the basis of the steric hindrance imposed by the coordination of the ligands, which determines the more stable geometrical isomer in each case.
Non‐esterified fatty acids induce apoptosis via a ROS‐dependent mechanism involving the mitochondrial pathway in bovine abomasal smooth muscle cells
Authors: Wei Teng , Tian Wulin , Xie Guanghong
Published: June 2014

Increased blood non‐esterified fatty acid (NEFA) concentrations might be implicated as a factor that plays a role in the pathogenesis of gastrointestinal motility disorder, such as abomasal displacement. We sought to elucidate possible effects of high concentrations of NEFA on primary cultured bovine abomasal smooth muscle cells (BSMC). BSMC treated with high concentrations of NEFA resulted in decrease of cell viability and increase of cell apoptosis rate. NEFA treatment induced oxidative stress, as revealed by increased levels of ROS and MDA, while decreased the antioxidative abilities (SOD, CAT, GSH, and GSSG) in BSMC. Meanwhile, high concentrations of NEFA induced BSMC mitochondrial apoptotic cell death. Mitochondrial membrane potential decrease, increased Bax and decreased Bcl‐2, cytochrome c release, caspases activation, and apoptosis inducing factor (AIF) translocation were observed in NEFA‐treated cells. Pretreatment with the antioxidant N‐acetylcysteine (NAC) effectively reversed these NEFA‐induced events. In conclusion, these results show that NEFA induce BSMC apoptosis mainly via a ROS‐dependent mechanism involving the mitochondrial pathway.

The cytotoxicity of non‐esterified fatty acid (consist of oleic acid, linoleic acid, palmitic acid, stearic acid, and palmitoleic acid) on primary cultured bovine abomasal smooth muscle cell, and the underlying molecular mechanism.
Chemical Transformations and Photophysical Properties of meso‐Tetrathienyl‐Substituted Porphyrin Derivatives
Authors: Betoni Momo Patrícia , Pavani Christiane , Baptista Mauricio S. , Brocksom Timothy John , Thiago de Oliveira Kleber
Published: June 2014

The chemistry of meso‐tetrathienyl‐substituted porphyrin derivatives was explored, including synthesis and subsequent metalation, nitration and 1,3‐dipolar cycloaddition reactions. Mono‐ and tetra‐nitro‐meso‐tetrathienylporphyrins were prepared selectively under mild nitration conditions with NaNO2 and trifluoroacetic acid, and the corresponding chlorins and bacteriochlorins were also obtained by reaction with 1,3‐dipoles. The products were characterized in detail and their preliminary photophysical properties were evaluated.
Methanesulfonic Acid Mediated Cyclization and Meyer–Schuster Rearrangement of γ‐Amino‐ynones: Access to Enantiopure Pyrrolidine Exocyclic Vinylogous Amides
Authors: Vu Huy‐Dinh , Renault Jacques , Roisnel Thierry , Gouault Nicolas , Uriac Philippe
Published: June 2014

α‐ and β‐Amino‐ynones have been largely used to prepare heterocyclic rings in the presence of various electrophiles such as protic acids or gold(I). Herein we disclose the unprecedented formation of pyrrolidine exocyclic vinylogous amides, in place of the expected azepinones or piperidinones, starting from γ‐amino‐ynones derived from amino acids. The process involves a tandem 1,2‐addition of the protected nitrogen to the carbonyl group followed by a Meyer–Schuster rearrangement, which efficiently afforded enantiopure pyrrolidine exocyclic vinylogous amides. The sequence is poorly catalyzed by gold salts, but proved to be very efficient in the presence of methanesulfonic acid.
Dielectrophoretic separation of micron and submicron particles: A review
Authors: Dash Swagatika , Mohanty Swati
Published: June 2014

This paper provides an overview on separation of micron and submicron sized biological (cells, yeast, virus, bacteria, etc.) and nonbiological particles (latex, polystyrene, CNTs, metals, etc.) by dielectrophoresis (DEP), which finds wide applications in the field of medical and environmental science. Mathematical models to predict the electric field, flow profile, and concentration profiles of the particles under the influence of DEP force have also been covered in this review. In addition, advancements made primarily in the last decade, in the area of electrode design (shape and arrangement), new materials for electrode (carbon, silicon, polymers), and geometry of the microdevice, for efficient DEP separation of particles have been highlighted.
High‐throughput DNA separation in nanofilter arrays
Authors: Choi Sungup , Kim Ju Min , Ahn Kyung Hyun , Lee Seung Jong
Published: June 2014

We numerically investigated the dynamics of short double‐stranded DNA molecules moving through a deep‐shallow alternating nanofilter, by utilizing Brownian dynamics simulation. We propose a novel mechanism for high‐throughput DNA separation with a high electric field, which was originally predicted by Laachi et al. [Phys. Rev. Lett. 2007, 98, 098106]. In this work, we show that DNA molecules deterministically move along different electrophoretic streamlines according to their length, owing to geometric constraint at the exit of the shallow region. Consequently, it is more probable that long DNA molecules pass over a deep well region without significant lateral migration toward the bottom of the deep well, which is in contrast to the long dwelling time for short DNA molecules. We investigated the dynamics of DNA passage through a nanofilter facilitating electrophoretic field kinematics. The statistical distribution of the DNA molecules according to their size clearly corroborates our assumption. On the other hand, it was also found that the tapering angle between the shallow and deep regions significantly affects the DNA separation performance. The current results show that the nonuniform field effect combined with geometric constraint plays a key role in nanofilter‐based DNA separation. We expect that our results will be helpful in designing and operating nanofluidics‐based DNA separation devices and in understanding the polymer dynamics in confined geometries.
Ecomorphodynamics of rivers with converging boundaries
Authors: Perona Paolo , Crouzy Benoît , McLelland Stuart , Molnar Peter , Camporeale Carlo
Published: June 2014

Many rivers worldwide show converging sections where a characteristic limiting front for vegetation establishment on gravel bars is observed. An important conceptual model was advanced in 2006 by Gurnell and Petts, who demonstrated that for the convergent section of the Tagliamento River the downstream front of vegetation establishment can be explained by unit stream power. We introduce a theoretical framework based on 1D ecomorphodynamic equations modified to account for the biological dynamics of vegetation. We obtain the first analytical result explaining the position and river width where vegetation density is expected to vanish in relation to a characteristic streamflow magnitude and both hydraulic and biological parameters. We apply our model to a controlled experiment within a convergent flume channel with growing seedlings perturbed by periodic floods. For a range of timescales where hydrological and biological processes interact, we observe the formation of a front in the convergent section beyond which vegetation cannot survive, the location of which is explained by flow magnitude. This experiment confirms that the timescales of the involved processes and the unit stream power determine the existence and the position of the front within convergent river reaches, respectively. Copyright © 2014 John Wiley & Sons, Ltd.
Granitic coastal geomorphology: applying integrated terrestrial and bathymetric LiDAR with multibeam sonar to examine coastal landscape evolution
Authors: Kennedy David M. , Ierodiaconou Daniel , Schimel Alexandre
Published: June 2014

Coasts composed of resistant lithologies such as granite are generally highly resistant to erosion. They tend to evolve over multiple sea level cycles with highstands acting to remove subaerially weathered material. This often results in a landscape dominated by plunging cliffs with shore platforms rarely occurring. The long‐term evolution of these landforms means that throughout the Quaternary these coasts have been variably exposed to different sea level elevations which means erosion may have been concentrated at different elevations from today. Investigations of the submarine landscape of granitic coasts have however been hindered by an inability to accurately image the nearshore morphology. Only with the advent of multibeam sonar and aerial laser surveying can topographic data now be seamlessly collected from above and below sea level. This study tests the utility of these techniques and finds that very accurate measurements can be made of the nearshore thereby allowing researchers to study the submarine profile with the same accuracy as the subaerial profile. From a combination of terrestrial and marine LiDAR data with multibeam sonar data, it is found that the morphology of granite domes is virtually unaffected by erosion at sea level. It appears that evolution of these landscapes on the coast is a very slow process with modern sea level acting only to remove subaerially weathered debris. The size and orientation of the joints determines the erosional potential of the granite. Where joints are densely spaced (<2 m apart) or the bedrock is highly weathered can semi‐horizontal surfaces form. Copyright © 2014 John Wiley & Sons, Ltd.
Reconstructing historic Glacial Lake Outburst Floods through numerical modelling and geomorphological assessment: Extreme events in the Himalaya
Authors: Westoby Matthew J. , Glasser Neil F. , Hambrey Michael J. , Brasington James , Reynolds John M. , Hassan Mohamed A. A. M.
Published: June 2014

Recession of high‐mountain glaciers in response to climatic change frequently results in the development of moraine‐dammed glacial lakes. Moraine dam failure is often accompanied by the release of large volumes of water and sediment, termed a Glacial Lake Outburst Flood (GLOF). Chukhung Glacier is a small (~3 km2) receding valley glacier in Mt. Everest (Sagarmatha) National Park, Nepal. Unlike many Himalayan glaciers, which possess a thick mantle of supraglacial debris, its surface is relatively clean. The glacier terminus has receded 1.3 km from its maximum Holocene position, and in doing so provided the space for an ice‐contact moraine‐dammed lake to develop. The lake had a maximum volume of 5.5 × 105 m3 and drained as a result of breaching of the terminal moraine. An estimated 1.3 × 105 m3 of material was removed from the terminal moraine during breach development. Numerical dam‐breach modelling, implemented within a Generalised Likelihood Uncertainty Estimation (GLUE) framework, was used to investigate a range of moraine‐dam failure scenarios. Reconstructed outflow peak discharges, including failure via overtopping and piping mechanisms, are in the range 146–2200 m3 s‐1. Results from two‐dimensional hydrodynamic GLOF modelling indicate that maximum local flow depths may have exceeded 9 m, with maximum flow velocities exceeding 20 m s‐1 within 700 m of the breach. The floodwaters mobilised a significant amount of material, sourced mostly from the expanding breach, forming a 300 m long and 100 m wide debris fan originating at the breach exit. moraine‐dam. These results also suggest that inundation of the entire floodplain may have been achieved within ten minutes of initial breach development, suggesting that debris fan development was rapid. We discuss the key glaciological and geomorphological factors that have determined the evolution of a hazardous moraine‐dammed lake complex and the subsequent generation of a GLOF and its geomorphological impact. © 2014 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd.
Fate and effects of poly- and perfluoroalkyl substances in the aquatic environment: A review
Authors: Ahrens Lutz , Bundschuh Mirco
Published: June 2014

Polyfluoroalkyl and perfluoroalkyl substances (PFASs) are distributed ubiquitously in the aquatic environment, which raises concern for the flora and fauna in hydrosystems. The present critical review focuses on the fate and adverse effects of PFASs in the aquatic environment. The PFASs are continuously emitted into the environment from point and nonpoint sources such as sewage treatment plants and atmospheric deposition, respectively. Although concentrations of single substances may be too low to cause adverse effects, their mixtures can be of significant environmental concern. The production of C8-based PFASs (i.e., perfluorooctane sulfonate [PFOS] and perfluorooctanoate [PFOA]) is largely phased out; however, the emissions of other PFASs, in particular short-chain PFASs and PFAS precursors, are increasing. The PFAS precursors can finally degrade to persistent degradation products, which are, in particular, perfluoroalkane sulfonates (PFSAs) and perfluoroalkyl carboxylates (PFCAs). In the environment, PFSAs and PFCAs are subject to partitioning processes, whereby short-chain PFSAs and PFCAs are mainly distributed in the water phase, whereas long-chain PFSAs and PFCAs tend to bind to particles and have a substantial bioaccumulation potential. However, there are fundamental knowledge gaps about the interactive toxicity of PFAS precursors and their persistent degradation products but also interactions with other natural and anthropogenic stressors. Moreover, because of the continuous emission of PFASs, further information about their ecotoxicological potential among multiple generations, species interactions, and mixture toxicity seems fundamental to reliably assess the risks for PFASs to affect ecosystem structure and function in the aquatic environment. Environ Toxicol Chem 2014; 33:1921–1929. © 2014 SETAC
Analysis of phenolic compounds in commercial dried grape pomace by high‐performance liquid chromatography electrospray ionization mass spectrometry
Authors: Ramirez‐Lopez Lina M. , DeWitt Christina A. M.
Published: June 2014

By‐products obtained from winemaking processes still contain large amounts of phenolic compounds, especially phenolic acids, flavanols, flavonols, stilbenes, and flavonoids. Enzymatic hydrolysis was used for determination and characterization of phenolic acids, flavanols, flavonols, and stilbenes. Characterization of the flavonoids was achieved using acid hydrolysis with 0.1% hydrochloric acid. In addition, organic solvents as 50% methanol, 70% methanol, 50% acetone, 0.01% pectinase, and 100% petroleum ether were also evaluated. Reversed phase high‐performance liquid chromatography (RP‐HPLC) with diode array detector was used to identify phenolic compounds. Internal standard quantification was implemented using a five points of the UV‐visible absorption data collected at the wavelength of maximum absorbance. A total of 16 phenolic compounds were determined. The content differed from 1.19 to 1124 mg kg−1. Outcomes from HPLC study showed that gallic acid, (+) catechin hydrate, and (−) epicatechin gallate were the major phenolic compounds presented in the sample. Malvidin and pelargonidin 3‐O‐glucoside were the major anthocyanins monoglucosides.
Timed regulation of P-element-induced wimpy testis–interacting RNA expression during rat liver regeneration
Authors: Rizzo Francesca , Hashim Adnan , Marchese Giovanna , Ravo Maria , Tarallo Roberta , Nassa Giovanni , Giurato Giorgio , Rinaldi Antonio , Cordella Angela , Persico Marcello , Sulas Pia , Perra Andrea , Ledda-Columbano Giovanna M. , Columbano Amedeo , Weisz Alessandro
Published: June 2014

Small noncoding RNAs comprise a growing family of molecules that regulate key cellular processes, including messenger RNA (mRNA) degradation, translational repression, and transcriptional gene silencing. P-element-induced wimpy testis (PIWI)-interacting RNAs (piRNAs) represent a class of small RNAs initially identified in the germline of a variety of species, where they contribute to maintenance of genome stability, and recently found expressed also in stem and somatic cells, where their role and responsiveness to physiopathological signals remain elusive. Here, we investigated piRNA expression in rat liver and its response to the stimuli exerted by regenerative proliferation of this organ. Quantitative polymerase chain reaction analysis identify in the liver the RNAs encoding PIWIL2/HILI, PIWIL4/HIWI2, and other components of the piRNA biogenesis pathways, suggesting that this is indeed functional. RNA sequencing before, during, and after the wave of cell proliferation that follows partial hepatectomy (PH) identified ˜1,400 mammalian germline piRNAs expressed in rat liver, including 72 showing timed changes in expression 24-48 hours post-PH, a timing that corresponds to cell transition through the S phase, returning to basal levels by 168 hours, when organ regeneration is completed and hepatocytes reach quiescence. Conclusion: The piRNA pathway is active in somatic cells of the liver and is subject to regulation during the pathophysiological process of organ regeneration, when these molecules are available to exert their regulatory functions on the cell genome and transcriptome, as demonstrated by the identification of several liver mRNAs representing candidate targets of these regulatory RNAs. (Hepatology 2014;60:798–806)
Diffusive equilibrium in thin films provides evidence of suppression of hyporheic exchange and large‐scale nitrate transformation in a groundwater‐fed river
Authors: Byrne P. , Zhang H. , Ullah S. , Binley A. , Heathwaite A.L. , Heppell C.M. , Lansdown K. , Trimmer M.
Published: June 2014

The hyporheic zone of riverbed sediments has the potential to attenuate nitrate from upwelling, polluted groundwater. However, the coarse‐scale (5–10 cm) measurement of nitrogen biogeochemistry in the hyporheic zone can often mask fine‐scale (<1 cm) biogeochemical patterns, especially in near‐surface sediments, leading to incomplete or inaccurate representation of the capacity of the hyporheic zone to transform upwelling NO3−. In this study, we utilised diffusive equilibrium in thin‐films samplers to capture high resolution (cm‐scale) vertical concentration profiles of NO3−, SO42−, Fe and Mn in the upper 15 cm of armoured and permeable riverbed sediments. The goal was to test whether nitrate attenuation was occurring in a sub‐reach characterised by strong vertical (upwelling) water fluxes. The vertical concentration profiles obtained from diffusive equilibrium in thin‐films samplers indicate considerable cm‐scale variability in NO3− (4.4 ± 2.9 mg N/L), SO42− (9.9 ± 3.1 mg/l) and dissolved Fe (1.6 ± 2.1 mg/l) and Mn (0.2 ± 0.2 mg/l). However, the overall trend suggests the absence of substantial net chemical transformations and surface‐subsurface water mixing in the shallow sediments of our sub‐reach under baseflow conditions. The significance of this is that upwelling NO3−‐rich groundwater does not appear to be attenuated in the riverbed sediments at <15 cm depth as might occur where hyporheic exchange flows deliver organic matter to the sediments for metabolic processes. It would appear that the chemical patterns observed in the shallow sediments of our sub‐reach are not controlled exclusively by redox processes and/or hyporheic exchange flows. Deeper‐seated groundwater fluxes and hydro‐stratigraphy may be additional important drivers of chemical patterns in the shallow sediments of our study sub‐reach. © 2015 The Authors. Hydrological Processes Published by John Wiley & Sons Ltd.
Drug development for pediatric neurogenic bladder dysfunction: Dosing, endpoints, and study design
Authors: Momper Jeremiah D. , Karesh Alyson , Green Dionna J. , Hirsch Mark , Khurana Mona , Lee Jinoo , Kim Myong‐Jin , Mulugeta Yeruk , Sachs Hari C. , Yao Lynne , Burckart Gilbert J.
Published: June 2014

Pediatric drug development is challenging when a product is studied for a pediatric disease that has a different underlying etiology and pathophysiology compared to the adult disease. Neurogenic bladder dysfunction (NBD) is such a therapeutic area with multiple unsuccessful development programs. The objective of this study was to critically evaluate clinical trial design elements that may have contributed to unsuccessful drug development programs for pediatric NBD. Trial design elements of drugs tested for pediatric NBD were identified from trials submitted to the U.S. Food and Drug Administration. Data were extracted from publically available FDA reviews and labeling and included trial design, primary endpoints, enrollment eligibilities, and pharmacokinetic data. A total of four products were identified. Although all four programs potentially provided clinically useful information, only one drug (oxybutynin) demonstrated efficacy in children with NBD. The lack of demonstrable efficacy for the remainder of the products illustrates that future trials should give careful attention to testing a range of doses, using objectively measured, clinically meaningful endpoints, and selecting clinical trial designs that are both interpretable and feasible. Compiling the drug development experience with pediatric NBD will facilitate an improved approach for future drug development for this, and perhaps other, therapeutic areas.
Comparative study of the extraction methods for recovery of carotenoids from algae: extraction kinetics and effect of different extraction parameters
Authors: Mäki‐Arvela Päivi , Hachemi Imane , Murzin Dmitry Yu.
Published: June 2014

Carotenoid extraction from algae is currently under intensive research due to the increased demand for naturally occurring compounds, which are especially rich in biologically active isomers. Furthermore, natural carotenoids exhibit greater stability than synthetic ones. Conventional liquid extraction suffers from several drawbacks, such as use of high amounts of solvent, and several extraction steps. In this work carotenoid extraction from algae using different methods, such as microwave and ultrasound assisted extraction as well as pressurized liquid extraction and extraction with supercritical CO2 and ethane, is summarized together with modelling of extraction kinetics. In addition carotenoid availability, algae pretreatment, stability of extracts, their antioxidative and antimicrobial activities as well as downstream processing and storage of algae extracts have been reviewed. As a conclusion it can be stated that carotenoid extraction is complex, demanding optimization of the carotenoid yield and antioxidative stability, which are often inversely proportional. © 2014 Society of Chemical Industry
Online prediction of product titer and solubility of recombinant proteins in Escherichia coli fed‐batch cultivations
Authors: Luchner Markus , Striedner Gerald , Cserjan‐Puschmann Monika , Strobl Florian , Bayer Karl
Published: June 2014

BACKGROUND

A goal in the production of biopharmaceuticals is to replace the cost‐intensive, empirical ‘quality by testing’ approach with rational, knowledge‐based ‘quality by design’ concepts. The major challenges in this context are the complexity of bioprocesses and the limited online access to process variables related to product quality. The implementation of advanced monitoring strategies combined with chemometric‐based approaches represents a strategy to overcome this bottleneck.

RESULTS

A series of recombinant E. coli fed‐batch production processes was conducted to provide an accurate data set for development of predictive statistical models. The applicability of partial least squares regression and radial basis function artificial neural network‐based models to predict gene dosage, product titer, and solubility of the target protein was evaluated. In addition to signals from standard online measurements, multi‐wavelength fluorescence signals turned out to provide essential information for prediction of product titer and quality.

CONCLUSIONS

The application of advanced process monitoring concepts comprising recently established analytical targets and statistical modeling allows for real‐time prediction of product related not directly accessible process variables. Availability of such process information facilitates design of advanced process‐control strategies and will strongly support the implementation of quality by design in biopharmaceutical production. © 2014 Society of Chemical Industry
Synthesis and Structural Characterization of Ethynylene‐Bridged Bisazines Featuring Various α‐Substitution
Authors: Hübscher Jörg , Seichter Wilhelm , Gruber Thomas , Kortus Jens , Weber Edwin
Published: June 2014

A series of bispyridines and bispyrimidines 1a, 1b, 1c, 1d, 1e showing the heterocycles attached to both ends of an ethynylene unit and being α‐substituted with chloro, tert‐butylthio, and methoxy groups have been synthesized via cross‐coupling technique and their crystal structures studied by X‐ray diffraction analysis. Supramolecular interactions of C–H···N and π···π stacking type were found to largely dominate the structures according to the compound species. A trial was given to deduce the markedly differing temperatures of melting among the compounds from special features of the crystal structures.
Chambered cuticle, pellicles, strange sensilla, and extraordinary muscle arrangements: A study of the micropterigid larval trunk (Lepidoptera: Micropterigidae)
Authors: Dupont Steen T.K.
Published: June 2014

Cover illustration. The cover image shows the dorsal habitus of the elusive larvae of Sabatinca chalcophanes, Micropterigidae which has long been considered the sister group to the Lepidoptera. The head morphology of the larvae shows rather plesiomorphic characters, but the postcephalic trunk of these animals whose slug‐like creeping gait is so unlike that of typical caterpillars must be considered a suite of autapomorphic characters. In this issue of the Journal of Morphology, Steen Dupont (pp. 797–82110.1002/jmor.20264) presents a detailed morphological analysis of the unusual morphology of these larvae and analyzes it in the context of phylogeny.
Biocontrol agents‐mediated suppression of oxalic acid induced cell death during Sclerotinia sclerotiorum–pea interaction
Authors: Jain Akansha , Singh Akanksha , Singh Surendra , Sarma Birinchi Kumar , Singh Harikesh Bahadur
Published: June 2014

Oxalic acid (OA) is an important pathogenic factor during early Sclerotinia sclerotiorum‐host interaction and might work by reducing hydrogen peroxide production (H2O2). In the present investigation, oxalic acid‐induced cell death in pea was studied. Pea plants treated with biocontrol agents (BCAs) viz., Pseudomonas aeruginosa PJHU15, Bacillus subtilis BHHU100, and Trichoderma harzianum TNHU27 either singly and/or in consortium acted on S. sclerotiorum indirectly by enabling plants to inhibit the OA‐mediated suppression of oxidative burst via induction of H2O2. Our results showed that BCA treated plants upon treatment with culture filtrate of the pathogen, conferred the resistance via. significantly decreasing relative cell death of pea against S. sclerotiorum compared to control plants without BCA treatment but treated with the culture filtrate of the pathogen. The results obtained from the present study indicate that the microbes especially in consortia play significant role in protection against S. sclerotiorum by modulating oxidative burst and partially enhancing tolerance by increasing the H2O2 generation, which is otherwise suppressed by OA produced by the pathogen.
Extraction of functional ingredients from spinach (Spinacia oleracea L.) using liquid solvent and supercritical CO2 extraction
Authors: Jaime Laura , Vázquez Erika , Fornari Tiziana , López‐Hazas María del Carmen , García‐Risco Mónica R , Santoyo Susana , Reglero Guillermo
Published: June 2014

BACKGROUND

In this work three different techniques were applied to extract dry leaves of spinach (Spinacia oleracea): solid–liquid extraction (SLE), pressurised liquid extraction (PLE) and supercritical fluid extraction (SFE) to investigate the influence of extraction solvent and technique on extracts composition and antioxidant activity. Moreover, the influence of carotenoids and phenolic compounds on the antioxidant and anti‐inflammatory activities of spinach extracts was also studied.

RESULTS

The higher concentrations of carotenoids and the lower content of phenolic compounds were observed in the supercritical CO2 extracts; whereas water and/or ethanol PLE extracts presented low amounts of carotenoids and the higher concentrations of phenolic compounds. PLE extract with the highest content of phenolic compounds showed the highest antioxidant activity, although SFE carotenoid rich extract also showed a high antioxidant activity. Moreover, both extracts presented an important anti‐inflammatory activity.

CONCLUSION

PLE seems to be a good technique for the extraction of antioxidant and anti‐inflammatory compounds from spinach leaves. Moreover, spinach phenolic compounds and carotenoids present a high antioxidant activity, whereas spinach carotenoids seem to show a higher anti‐inflammatory activity than phenolic compounds. It is worth noting that of our knowledge this is the first time the anti‐inflammatory activity of lipophilic extracts from spinach leaves is reported. © 2014 Society of Chemical Industry
Farmers' Perceptions about the Influence of Land Quality, Land Fragmentation and Tenure Systems on Sustainable Land Management in the North Western Ethiopian Highlands
Authors: Teshome Akalu , de Graaff Jan , Ritsema Coen , Kassie Menale
Published: June 2014

Land is a scarce resource in the highlands of Ethiopia. Its sustainable use is highly affected by bio‐physical and institutional factors. The purpose of this research is to investigate farmers' perceptions about land quality, land fragmentation and tenure systems and their influences on sustainable land management (SLM) investments in the North Western Ethiopian Highlands. The study is based on a detailed farm survey among 300 households and 1,700 parcels in three watersheds. Simple descriptive statistics were applied to analyse the perception of farmers about land‐related factors. A multivariate probit (MVP) model was used to analyse the effect of land‐related factors on the interdependent investment decisions of SLM practices (Bunds, Compost/Manure and Fertilizer) using a multiple parcel‐level survey. The study shows that on average, sample households managed 4·54 parcels in different locations with an average parcel size of 0·26 ha. The MVP model analysis indicates that farmers invest a combination of practices at parcel level by considering substitution and complementarity effects of the practices. The results also reveal how land quality (e.g. slope and soil fertility status), land fragmentation (parcel size and distance of parcel from homestead) and tenure arrangements influence farmers' investments in SLM practices. The overall results indicate that farm land attributes promote or hinder investments, and tenure systems regulate the decisions about investments. Policy makers should take into consideration these various land‐related factors in designing and implementing SLM policies and programmes. Copyright © 2014 John Wiley & Sons, Ltd.
One‐Pot Fabrication of Rattle‐Like Capsules with Multicores by Pickering‐Based Polymerization with Nanoparticle Nucleation
Authors: Zou Shengwen , Hu Yang , Wang Chaoyang
Published: June 2014

Rattle‐like polymer capsules with multicores in one shell are facilely fabricated by oil‐in‐water Pickering emulsion polymerization for the first time. The oil phase contains hydrophobic silica nanoparticles dispersed in polymerizable monomer, styrene, and unpolymerizable solvent, hexadecane. The multicore rattle‐like capsules are facilely produced after the polymerization of monomers in the oil droplets. The key point of this one‐pot method lies in the nucleation of hydrophobic silica and the phase separation between the resulting polystyrene and hexadecane. The influences of the contents of silica, hexadecane, cross‐linker, and stabilizer on the structure and morphology of rattle‐like capsules are systematically investigated. Moreover, functionalization of the rattle‐like capsules can be developed easily by varying hydrophobic nucleation nanoparticles in the oil phase. This work opens up a new route to fabricate multilevel capsules or spheres.

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Brief overview on2H NMR studies of polysiloxane‐based side‐chain nematic elastomers
Authors: Domenici Valentina , Milavec Jerneja , Zupančič Blaž , Bubnov Alexej , Hamplova Vera , Zalar Boštjan
Published: June 2014

This is a brief overview on recent studies on liquid crystalline elastomers (LCEs) based on polysiloxane chain, in the form of monodomain films, selectively2H‐labeled in different parts of the LCE samples, i.e. on the crosslinker or mesogenic units.2H NMR spectroscopic techniques were used to measure the temperature dependence of the quadrupolar splittings, line widths and relaxation times,T1andT2. From these data, several information about the orientational order parameter,S, of various LCE fragments, thermodynamic features of the isotropic–nematic transition and main motional processes could be generalized for this type of elastomers. Copyright © 2014 John Wiley & Sons, Ltd.
Web‐spline‐based finite element approximation of some quasi‐newtonian flows: Existence‐uniqueness and error bound
Authors: Chaudhary Sudhakar , Kumar V. V. K. Srinivas
Published: June 2014

This article deals with the web‐spline‐based finite element approximation of quasi‐Newtonian flows. First, we consider the scalar elliptic p‐Laplace problem. Then, we consider quasi‐Newtonian flows where viscosity obeys power law or Carreau law. We prove well‐posedness at the continuous as well as the discrete level. We give some error bounds for the solution of quasi‐Newtonian flow problem based on the web‐spline method. Finally, we provide the numerical results for the p‐Laplace problem. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq31: 54–77, 2015
Agenesis of ductus venosus in sequential first and second trimester screening
Authors: Iliescu D. G. , Cara M. L. , Tudorache S. , Antsaklis P. , Novac L. V. , Antsaklis A. , Cernea N.
Published: June 2014

Objective

The goal of this study is to evaluate the potential of first trimester (FT) screening in the diagnosis of agenesis of the ductus venosus (ADV) and to study its prevalence in a low‐risk population, the associated conditions, and pregnancy outcome.

Method

Prospective, sequential screening study at two tertiary units with morpho‐functional evaluation of the ductus venosus during the first and second trimester screening. We quantified the FT detection rate, prevalence, and associated conditions: umbilical shunting type, concomitant anomalies, and outcome.

Results

In 6114 consecutive pregnancies, we identified 11 cases of ADV. Ten (91%) were identified during the FT examination. The prevalence was 1 in 556, similar for both centers (1/478 vs. 1/691). Major structural defects and fetal effusions were detected in 8 (73%). twenty two percent had a major chromosomal abnormality. In 3 cases, the anomaly was isolated and had normal outcome, independent of liver by‐pass, caliber of the shunt, and NT thickness.

Conclusions

Agenesis of the ductus venosus can be detected during FT. The early detection of ADV is important given its high association with major abnormalities. © 2014 John Wiley & Sons, Ltd.
High‐Density Lipoprotein Nanoparticles Deliver RNAi to Endothelial Cells to Inhibit Angiogenesis
Authors: Tripathy Sushant , Vinokour Elena , McMahon Kaylin M. , Volpert Olga V. , Thaxton C. Shad
Published: June 2014

Systemic delivery of therapeutic nucleic acids to target cells and tissues outside of the liver remains a major challenge. A biomimetic high‐density lipoprotein nanoparticle (HDL NP) is synthesized for delivery of a cholesteryl‐modified therapeutic nucleic acid to vascular endothelial cells (ECs), a cell type naturally targeted by HDL. HDL NPs adsorb cholesteryl‐modified oligonucleotides and protect them from nuclease degradation. As proof of principle, we deliver RNAi targeting vascular endothelial growth factor receptor 2 (VEGFR2) to ECs to effectively silence target mRNA and protein expression in vitro. In addition, data show that treatment strongly attenuates in vivo neovascularization measured using a standard angiogenesis assay and in hypervascular tumor allografts where a striking reduction in tumor growth is observed. For effective delivery, HDL NPs require the expression of the cell surface protein scavenger receptor type‐B1 (SR‐B1). No toxicity of HDL NPs is measured in vitro or after in vivo administration. Thus, by using a biomimetic approach to nucleic acid delivery, data demonstrate that systemically administered RNAi–HDL NPs target SR‐B1 expressing ECs to deliver functional anti‐angiogenic RNAi as a potential treatment of cancer and other neovascular diseases.
Temporin‐SHa peptides grafted on gold surfaces display antibacterial activity
Authors: Lombana Andres , Raja Zahid , Casale Sandra , Pradier Claire‐Marie , Foulon Thierry , Ladram Ali , Humblot Vincent
Published: June 2014

Development of resistant bacteria onto biomaterials is a major problem leading to nosocomial infections. Antimicrobial peptides are good candidates for the generation of antimicrobial surfaces because of their broad‐spectrum activity and their original mechanism of action (i.e. rapid lysis of the bacterial membrane) making them less susceptible to the development of bacterial resistance. In this study, we report on the covalent immobilisation of temporin‐SHa on a gold surface modified by a thiolated self‐assembled monolayer. Temporin‐SHa (FLSGIVGMLGKLFamide) is a small hydrophobic and low cationic antimicrobial peptide with potent and very broad‐spectrum activity against Gram‐positive and Gram‐negative bacteria, yeasts and parasites. We have analysed the influence of the binding mode of temporin‐SHa on the antibacterial efficiency by using a covalent binding either via the peptide NH2 groups (random grafting of α‐ and ε‐NH2 to the surface) or via its C‐terminal end (oriented grafting using the analogue temporin‐SHa‐COOH). The surface functionalization was characterised by IR spectroscopy (polarisation modulation reflection absorption IR spectroscopy) while antibacterial activity against Listeria ivanovii was assessed by microscopy techniques, such as atomic force microscopy and scanning electron microscopy equipped with a field emission gun. Our results revealed that temporin‐SHa retains its antimicrobial activity after covalent grafting. A higher amount of bound temporin‐SHa is observed for the C‐terminally oriented grafting compared with the random grafting (NH2 groups). Temporin‐SHa therefore represents an attractive candidate as antimicrobial coating agent. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.
A Nonparametric Phase I Control Chart for Individual Observations Based on Empirical Likelihood Ratio
Authors: Ning Wei , Yeh Arthur B. , Wu Xinqi , Wang Boxiang
Published: June 2014

One common challenge in nonmanufacturing control chart applications is that many of the nonmanufacturing quality characteristics are not normally distributed. In these applications, normal transformation of the observations is certainly feasible; however, it will be done at the expense of the interpretability of the analysis that is particularly important to control chart users in nonmanufacturing industries.

Most of the existing nonparametric control charts are designed for Phase II monitoring. Little has been done in developing nonparametric Phase I control charts especially for individual observations that are prevalent in nonmanufacturing applications. In this work, we propose a new nonparametric Phase I control chart for monitoring the location parameter whose construction is essentially based on the empirical likelihood ratio test. The performance of the proposed chart, in terms of the signal probability, compares favorably with the recently developed charts for individual observations. A nonmanufacturing example is included in which the proposed chart and the other competing charts are applied and compared. Copyright © 2014 John Wiley & Sons, Ltd.