bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, Spectral, Thermal Studies of Co(II), Ni(II), Cu(II) and Zn(II)‐arginato Complexes. Crystal Structure of Monoaquabis(arginato‐κO,κN)copper(II). [Cu(arg)2(H2O)].NaNO3
Authors: Köse Dursun Ali , Toprak Emre , Avcı Emre , Avcı Gülçin Alp , Şahin Onur , Büyükgüngör Orhan 
Published: April 2014

AbstractTransition metal complexes of arginine (using Co(II), Ni(II), Cu(II) and Zn(II) cations separately) were synthesized and characterized by FTIR, TG/DTA‐DrTG, UV‐Vis spectroscopy and elemental analysis methods. Cu(II)‐Arg complex crystals was found suitable for x‐ray diffraction studies. It was contained, one mole CuII and Na+ ions, two arginate ligands, one coordinated aqua ligand and one solvent NO3− group in the asymmetric unit. The principle coordination sites of metal atom have been occupied by two N atoms of arginate ligands, two carboxylate O atoms, while the apical site was occupied by one O atom for CuII cation and two O atoms for CoII, NiII, ZnII atoms of aqua ligands. Although CuII ion adopts a square pyramidal geometry of the structure. CoII, NiII, ZnII cations have octahedral due to coordination number of these metals. Neighbouring chains were linked together to form a three‐dimensional network via hydrogen‐bonding between coordinated water molecule, amino atoms and O atoms of the bridging carboxylate groups. CuII complex was crystallized in the monoclinic space group P21, a = 8.4407(5) Å, b = 12.0976(5) Å, c = 10.2448(6) Å, V = 1041.03(10) Å3, Z = 2. Structures of the other metal complexes were similar to CuII complex, because of their spectroscopic studies have in agreement with each other. Copper complex has shown DNA like helix chain structure. Lastly, anti‐bacterial, anti‐microbial and anti‐fungal biological activities of complexes were investigated.
Determination of Factors Affecting the Enzymatic Hydrolysis of Low Severity Acid‐steam Pretreated Agro‐residue
Authors: Sen Biswarup 
Published: April 2014

AbstractAgro‐residues and their hydrolyzates are precursors for synthesis of biofuels and mesoporous carbons. However, factors like pH, biomass loading, temperature, and enzyme affect the recovery of carbon sugars, and limit the hydrolysis. This study determined the main factors affecting the hydrolysis by Principal Component Analysis (PCA). Corn cob was added to 1.2% hydrochloric acid and subjected to steam at 121 °C, 20 min (low‐severity, Step 1) following enzymatic hydrolysis (Step 2). Factor levels i.e., pH (4.5‐7.5), temperature (37, 45, 55 °C), biomass loading (50, 100, 200 g/L) and enzyme type (Viscozyme L and Cellulase, Sigma) were adjusted in Step 2. PCA of standardized measured variables (glucose, xylose, arabinose, reducing sugars (RS) and hydroxymethylfurfural (HMF) concentrations; and yields of glucose, xylose and RS) at various factor levels was performed. Principal component 1 and 2 could explain ca. 96% of the data variance (Fig. 1). Low biomass loading correlated with high yields of glucose, xylose and RS, whereas pH 5.5, 45 °C and cellulase correlated with high concentrations of glucose, xylose and RS. PCA can be an effective tool in the design of efficient hydrolysis method and evaluation of factors affecting pretreatment method.
Effect of Starvation upon Activity of Microorganisms Degrading 4‐Chlorophenol
Authors: Moreno‐Andrade Iván , Kumar Gopalakrishnan , Buitrón Germán 
Published: April 2014

AbstractThe variation of the microbial activity during starvation of microorganisms degrading 4‐chlorophenol was evaluated in a sequencing batch reactor. During the acclimation, a reduction in the degradation time and an increase in the specific degradation rate were observed. After the acclimation, the biomass was exposed to different starvation periods (8 to 36 h). The results showed that the starvation could decrease the microbial activity and composition. A reduction from 44 to 21% was observed on the specific removal rate, and from 35 to 26% on the specific oxygen uptake rate. The extension of the deacclimation of starved microorganisms was affected by the history of the culture. The effect of starvation on the degradation rate was less significant when microorganisms were starved, recovered and then starved again, than in the case where starvation is cyclically presented without a recovery period.
Silver Nitrate‐Catalyzed Selective Air Oxidation of Benzylic and Allylic Alcohols to Corresponding Aldehydes or Ketones
Authors: Wang Jiayi , Li Yuan , Peng Yanqing , Song Gonghua 
Published: April 2014

AbstractThe liquid phase selective air oxidation of benzylic and allylic alcohols to corresponding aldehydes or ketones has been achieved in high yields with catalytic amount of AgNO3 and in the presence of Na2CO3.
Boundary Properties of Factorial Classes of Graphs
Authors: Lozin Vadim V. , Zamaraev Victor 
Published: April 2014

AbstractFor a class of graphs X, let be the number of graphs with vertex set in the class X, also known as the speed of X. It is known that in the family of hereditary classes (i.e. those that are closed under taking induced subgraphs) the speeds constitute discrete layers and the first four lower layers are constant, polynomial, exponential, and factorial. For each of these four layers a complete list of minimal classes is available, and this information allows to provide a global structural characterization for the first three of them. The minimal layer for which no such characterization is known is the factorial one. A possible approach to obtaining such a characterization could be through identifying all minimal superfactorial classes. However, no such class is known and possibly no such class exists. To overcome this difficulty, we employ the notion of boundary classes that has been recently introduced to study algorithmic graph problems and reveal the first few boundary classes for the factorial layer.
Distinct frequency dependent effects of whole‐body vibration on non‐fractured bone and fracture healing in mice
Authors: Wehrle Esther , Wehner Tim , Heilmann Aline , Bindl Ronny , Claes Lutz , Jakob Franz , Amling Michael , Ignatius Anita 
Published: April 2014

ABSTRACTLow‐magnitude high‐frequency vibration (LMHFV) provokes anabolic effects in non‐fractured bone; however, in fracture healing, inconsistent results were reported and optimum vibration conditions remain unidentified. Here, we investigated frequency dependent effects of LMHFV on fracture healing. Twelve‐week‐old, female C57BL/6 mice received a femur osteotomy stabilized using an external fixator. The mice received whole‐body vibrations (20 min/day) with 0.3g peak‐to‐peak acceleration and a frequency of either 35 or 45 Hz. After 10 and 21 days, the osteotomized femurs and intact bones (contra‐lateral femurs, lumbar spine) were evaluated using bending‐testing, µ‐computed tomography, and histomorphometry. In non‐fractured trabecular bone, vibration with 35 Hz significantly increased the relative amount of bone (+28%) and the trabecular number (+29%), whereas cortical bone was not influenced. LMHFV with 45 Hz failed to provoke anabolic effects in trabecular or cortical bone. Fracture healing was not significantly influenced by whole‐body vibration with 35 Hz, whereas 45 Hz significantly reduced bone formation (−64%) and flexural rigidity (−34%) of the callus. Although the exact mechanisms remain open, our results suggest that small vibration setting changes could considerably influence LMHFV effects on bone formation in remodeling and repair, and even disrupt fracture healing, implicating caution when treating patients with impaired fracture healing. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1006–1013, 2014.
Stakeholders' Perceptions about Fire Impacts on Lithuanian Protected Areas
Authors: Pereira Paulo , Mierauskas Pranas , Novara Agata 
Published: April 2014

AbstractThe aim of this work is to study Lithuanian stakeholders' perceptions of fire impacts in protected areas. For this study, the stakeholders consisted of foresters, ecologists and farmers. A clear understanding of the opinions of stakeholders about fire effects on environmental, social and economic aspects of Lithuanian protected areas will allow an assessment of the stakeholders' reaction to fire policy, including government measures towards fire prevention, suppression and application of prescribed fire to landscape management. The results showed that stakeholders in general think that fire is not a threat to Lithuania and to the ecological processes in the protected areas. However, they agree that fires have negative impacts on soil properties and fertility but are not to an irremediable or irrecoverable extent. Stakeholders disagree that fire has positive consequences for agricultural and cattle activities but agreed that vegetation recovers quickly. They do not see fire as a social and economic problem, do not agree that prescribed fire could be used to landscape management, and believe that mechanical thinning is a better management tool than prescribed fire. Stakeholders agree that fire does not have negative impacts on the biodiversity. These opinions depended on the age group of the respondent but especially on the respondent's professional occupation. Copyright © 2014 John Wiley & Sons, Ltd.
Facile Synthesis of Brush Poly(phosphoamidate)s via One‐Pot Tandem Ring‐Opening Metathesis Polymerization and Atom Transfer Radical Polymerization
Authors: Ding Liang , Qiu Jun , Wei Jun , Zhu Zhenshu 
Published: April 2014

Poly(2‐(dimethylamino)ethyl methacrylate) (PDMAEMA)‐based brush poly(phosphoamidate)s are successfully synthesized by a combination of ring‐opening metathesis polymerization (ROMP) and atom transfer radical polymerization (ATRP) following either a commutative two‐step procedure or a straightforward one‐pot process using Grubbs ruthenium‐based catalysts for tandem catalysis. Compared with the traditional polymerization method, combining ROMP and ATRP in a one‐pot process allows the preparation of brush copolymers characterized by a relatively moderate molecular weight distribution and quantitative conversion of monomer. Moreover, the surface morphologies and aggregation behaviors of these polymers are studied by AFM and TEM measurements.
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The ultra‐relativistic Euler equations
Authors: Abdelrahman Mahmoud A.E. , Kunik Matthias 
Published: April 2014

AbstractWe study the ultra‐relativistic Euler equations for an ideal gas, which is a system of nonlinear hyperbolic conservation laws. We first analyze the single shocks and rarefaction waves and solve the Riemann problem in a constructive way. Especially, we develop an own parametrization for single shocks, which will be used to derive a new explicit shock interaction formula. This shock interaction formula plays an important role in the study of the ultra‐relativistic Euler equations. One application will be presented in this paper, namely, the construction of explicit solutions including shock fronts, which gives an interesting example for the non‐backward uniqueness of our hyperbolic system. Copyright © 2014 John Wiley & Sons, Ltd.
Some new nonlinear wave solutions and their convergence for the (2+1)‐dimensional Broer–Kau–Kupershmidt equation
Authors: Yan Weifang , Liu Zhengrong 
Published: April 2014

AbstractWe use the bifurcation method of dynamical systems to study the (2+1)‐dimensional Broer–Kau–Kupershmidt equation. We obtain some new nonlinear wave solutions, which contain solitary wave solutions, blow‐up wave solutions, periodic smooth wave solutions, periodic blow‐up wave solutions, and kink wave solutions. When the initial value vary, we also show the convergence of certain solutions, such as the solitary wave solutions converge to the kink wave solutions and the periodic blow‐up wave solutions converge to the solitary wave solutions. Copyright © 2014 John Wiley & Sons, Ltd.
Detection of dynamics and phase separation in polymers using 2D 1H NMR in solids
Authors: Wilhelm M. , Lehmann S. , Jäger C. , Spiess H. W. , Jerome R. 
Published: April 2014

AbstractIt has been demonstrated that 1H 2D NMR of solids allows the correlation of structural information [1H chemical shift via combined rotation and multiple pulse spectroscopy, (CRAMPS)] in one frequency dimension with information on the dynamics (1H wideline) in the second dimension. Furthermore, domain sizes of individual phases found in heterogeneous solids can be determined by modelling 1H‐1H spin diffusion occurring during a mixing period tm. The experiment was applied to a poly(ethylene oxide)—polystyrene (PEO‐b‐PS) diblock copolymer. With standard double resonance magic angle spinning equipment, mobile poly(ethylene oxide) and mainly rigid polystyrene blocks in the polymer can be discriminated. By calibration with small‐angle x‐ray scattering data for the diblock copolymer, the spin diffusion coefficient for a system of intermediate mobility can be established. Thereby one can to fill the gap within the series of spin diffusion coefficients of highly mobile systems on the one hand and rigid systems on the other. Further applications of the experiment are discussed.
Quantification of cerebral perfusion using dynamic quantitative susceptibility mapping
Authors: Xu Bo , Spincemaille Pascal , Liu Tian , Prince Martin R. , Dutruel Silvina , Gupta Ajay , Thimmappa Nanda Deepa , Wang Yi 
Published: April 2014

PurposeThe purpose of this study is to develop a dynamic quantitative susceptibility mapping (QSM) technique with sufficient temporal resolution to map contrast agent concentration in cerebral perfusion imaging.MethodsThe dynamic QSM used a multiecho three‐dimensional (3D) spoiled gradient echo golden angle interleaved spiral sequence during contrast bolus injection. Four‐dimensional (4D) space‐time resolved magnetic field reconstruction was performed using the temporal resolution acceleration with constrained evolution reconstruction method. Deconvolution of the gadolinium‐induced field was performed at each time point with the morphology enabled dipole inversion method to generate a 4D gadolinium concentration map, from which three‐dimensional spatial distributions of cerebral blood volume and cerebral blood flow were computed.ResultsInitial in vivo brain imaging demonstrated the feasibility of using dynamic QSM for generating quantitative 4D contrast agent maps and imaging three‐dimensional perfusion. The cerebral blood flow obtained with dynamic QSM agreed with that obtained using arterial spin labeling.ConclusionDynamic QSM can be used to perform 4D mapping of contrast agent concentration in contrast‐enhanced magnetic resonance imaging. The perfusion parameters derived from this 4D contrast agent concentration map were in good agreement with those obtained using arterial spin labeling. Magn Reson Med 73:1540–1548, 2015. © 2014 Wiley Periodicals, Inc.
Evaluation of Anti‐oxidant and Acetylcholinesterase Activity and Identification of Polyphenolics of the Invasive Weed Dittrichia viscosa
Authors: Trimech Imen , Weiss Erika Krisztina , Chedea Veronica Sanda , Marin Daniela , Detsi Anastasia , Ioannou Efstathia , Roussis Vassilios , Kefalas Panagiotis 
Published: April 2014

ABSTRACTIntroductionThe bioactive metabolites derived from weeds have attracted the interest of the food and pharmaceutical industries due to their health benefits.ObjectiveTo evaluate the anti‐oxidant and acetylcholinesterase activity of Dittrichia viscosa extracts and characterise the polyphenolic metabolites using the LC coupled with diode‐array detection (DAD) and positive mode electrospray ionisation (ESI) MS method with a view to evaluating the exploitation potential of this invasive weed.Materials and methodsRoots and aerial parts of D. viscosa were extracted with solvents of increasing polarity and their major polyphenolic metabolites were identified by LC − DAD/ESI(+)/MS. The total phenolic content of the extracts was determined using the Folin–Ciocalteu method, while their anti‐oxidant activity was evaluated on the basis of their ability to scavenge the stable free radical 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and hydrogen peroxide. Thin‐layer chromatography was used to screen for acetylcholinesterase inhibitors.ResultsStem extracts gave the highest phenolic content, whereas the roots showed the lowest content. Twenty‐five polyphenolic constituents of the extracts were tentatively characterised according to their MS and UV spectroscopic data. Among the extracts studied, roots–ethyl acetate and flowers–diethyl ether revealed the highest activity according to the DPPH and chemiluminescence assays respectively.ConclusionThe metabolic profile of D. viscosa was studied and the structures of the major polyphenolic metabolites were tentatively assigned based on their MS and UV–vis spectra. The extracts exhibited high levels of anti‐oxidant and acetylcholinesterase inhibitory activity and the inhibitors are probably localised mainly in flowers and roots. Copyright © 2014 John Wiley & Sons, Ltd.
Piper betle Leaves: Profiling Phenolic Compounds by HPLC/DAD–ESI/MSn and Anti‐cholinesterase Activity
Authors: Ferreres Federico , Oliveira Andreia P. , Gil‐Izquierdo Angel , Valentão Patrícia , Andrade Paula B. 
Published: April 2014

ABSTRACTIntroductionPiper betle L. is a widely distributed plant in the tropical and subtropical regions, its leaves being largely consumed as a masticator and mouth freshener.ObjectiveThe purposes of this work were to characterise the phenolic profile of this species and to improve knowledge of its anti‐cholinesterase properties.MethodsThe phenolic composition of P. betle leaf aqueous and ethanol extracts was characterised by HPLC coupled with a diode‐array detector and combined with electrospray ionisation tandem MS, and in vitro cholinesterase inhibitory capacity of both extracts was assessed by spectrophotometric microassays. The effect on neuronal cells (SH‐SY5Y) viability was evaluated by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide reduction and lactate dehydrogenase leakage.ResultsTwelve phenolic compounds, comprising a phenylpropanoid, five cinnamoyl and six flavonoids derivatives were identified in P. betle leaves. Hydroxychavicol was the major compound in both extracts; however, the aqueous extract presented a greater diversity of compounds. Both extracts showed strong activity against both acetyl‐ and butyrylcholinesterase, which can be due, at least partially, to the phenolic composition. Furthermore, the aqueous extract proved to be cytotoxic to human neuroblastoma cells at concentrations higher than 500 µg/mL.ConclusionThe results suggest that the consumption of P. betle leaves as an infusion can have a positive impact in the prevention and treatment of neurodegenerative diseases. Apigenin and luteolin derivatives are reported for the first time in this species. Copyright © 2014 John Wiley & Sons, Ltd.
Optimisation of the Microplate Resazurin Assay for Screening and Bioassay‐guided Fractionation of Phytochemical Extracts against Mycobacterium tuberculosis
Authors: O'Neill Taryn E. , Li Haoxin , Colquhoun Caitlyn D. , Johnson John A. , Webster Duncan , Gray Christopher A. 
Published: April 2014

ABSTRACTIntroductionBecause of increased resistance to current drugs, there is an urgent need to discover new anti‐mycobacterial compounds for the development of novel anti‐tuberculosis drugs. The microplate resazurin assay (MRA) is commonly used to evaluate natural products and synthetic compounds for anti‐mycobacterial activity. However, the assay can be problematic and unreliable when screening methanolic phytochemical extracts.ObjectiveTo optimise the MRA for the screening and bioassay‐guided fractionation of phytochemical extracts using Mycobacterium tuberculosis H37Ra.MethodsThe effects of varying assay duration, resazurin solution composition, solvent (dimethyl sulphoxide – DMSO) concentration and type of microtitre plate used on the results and reliability of the MRA were investigated. The optimal bioassay protocol was applied to methanolic extracts of medicinal plants that have been reported to possess anti‐mycobacterial activity.ResultsThe variables investigated were found to have significant effects on the results obtained with the MRA. A standardised procedure that can reliably quantify anti‐mycobacterial activity of phytochemical extracts in as little as 48 h was identified. The optimised MRA uses 2% aqueous DMSO, with an indicator solution of 62.5 µg/mL resazurin in 5% aqueous Tween 80 over 96 h incubation.ConclusionThe study has identified an optimal procedure for the MRA when used with M. tuberculosis H37Ra that gives rapid, reliable and consistent results. The assay procedure has been used successfully for the screening and bioassay‐guided fractionation of anti‐mycobacterial compounds from methanol extracts of Canadian medicinal plants. Copyright © 2014 John Wiley & Sons, Ltd.
A constrained tracking control algorithm for linear systems based on a spline‐type parameter‐dependent Lyapunov function
Authors: Wada N. , Saeki M. , Masubuchi I. 
Published: April 2014

SummaryIn this paper, we propose a design method of a tracking control law for discrete‐time linear systems with actuator saturation. The feedback gain of the control law is actively changed online so that the control performance is improved based on the information of the state variable and the reference signal. The control law is designed with considering the rate of convergence of the tracking error. The design condition of the control law is derived as polynomially parameter‐dependent matrix inequalities, and a spline‐type parameter‐dependent Lyapunov function and a convex polytope are used to reduce the design condition to a finite number of LMIs. Three numerical examples are provided to illustrate effectiveness of the method. Copyright © 2014 John Wiley & Sons, Ltd.
Louvre Lens – Einfachheit und Komplexität
Authors: Pfanner Daniel , Grohmann Manfred , Bollinger Klaus 
Published: April 2014

AbstractDie Gebäudehüllen des Louvre Lens in Nordfrankreich vereinen nicht nur höchste gestalterische und materielle Anforderungen, sondern reagieren auch auf die strukturellen und bauphysikalischen Besonderheiten der schlanken, eingeschossigen Museumsbauten. Insbesondere die hohen Herausforderungen in der Planung der verglasten Gebäudehüllen werden beschrieben und die während des siebenjährigen Prozesses entwickelten Lösungsansätze erläutert.Louvre Lens – Simplicity and Complexity. The building envelopes of the Louvre museum in Lens in Northern France combine highest aesthetic and material requirements. They respond to the structural and physical characteristics of the slender single‐storey buildings. The façade engineering of the envelopes will be described with regard to the high requirements and to the seven year process from scratch to inauguration, with main focus on the glazed parts.