bluuebunny/crossref_metadata_2025 huggingface dataset:
Measuring production and consumption efficiencies using the slack‐based measure network data envelopment analysis approach: the case of low‐cost carriers
Authors: Chang Yu‐Chun , Yu Ming‐Miin
Published: March 2012

One of the most important outcomes of the deregulation of air transportation policy is the emergence of low‐cost carriers (LCCs) around the world. Although LCC airlines have been in operation for more than 30 years, not every LCC is successful. In order to reduce the inefficiencies of LCCs, this paper measures the performance of LCCs by using slack‐based measure network data envelopment analysis. This model combines both the production process with input orientation and the consumption process with output orientation into a unified model. Furthermore, envelopment map analysis LCCs are performed to determine the reasons for the LCCs' inefficiency and how improvements can be made. A sample of 16 low‐cost airlines from Europe, the USA, and Asia were selected for operational performance analysis. The results show that the main reason for easyJet's, US Airways', and Virgin Blue's inefficiency is production inefficiency, so these LCCs should reduce their input quantities to increase efficiency. Jet2, Aer Lingus, and JetBlue were, by contrast, found to be consumption inefficient; these LCCs should increase their output quantities in order to enhance performance. Copyright © 2012 John Wiley & Sons, Ltd.
Signal setting with demand assignment: global optimization with day‐to‐day dynamic stability constraints
Authors: Cantarella Giulio Erberto , Velonà Pietro , Vitetta Antonino
Published: March 2012

This paper deals with traffic signal setting with demand assignment. All approaches proposed in literature to address this problem are based on equilibrium assignment, well established in literature as well as in practice. Still, it is widely acknowledged that there are some relevant issues that may not be effectively addressed under the equilibrium approach, mainly uniqueness and stability, sensitivity to parameters and/or starting state. These issues should be better dealt with a day‐to‐day dynamic approach, through deterministic (or stochastic) process models. This issue seems relevant because optimization of signal timings under equilibrium assumptions may not guarantee that an effective solution is obtained, because it may well be not an attractor of the evolution over time.

The main contributions of this paper are as follows:

A simple but still effective deterministic process models based on exponential smoothing filters, which also include effects of signal setting, this model allows to state local stability of fixed‐point states (consistent with equilibrium patterns) through the spectral analysis of the Jacobian matrix of the recursive equations modelling the evolution over time of the system.

An expression of equilibrium stability conditions that can be included as constraints within global optimization models for signal setting; such models guarantee that stability conditions are satisfied by obtained solution.

Results from an application to a toy network, supporting major theoretical findings, are also reported. The very simple example allows for graphical representation to develop a general method useful to address implementation at real scale. Copyright © 2012 John Wiley & Sons, Ltd.
Technology transfer to developing economies
Authors: Sapp Meghan
Published: March 2012

Meghan Sapp from PANGEA looks at the opportunities for technology transfer for bioenergy in developing economies and challenges some major misconceptions. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd
Simultaneous determination of atorvastatin and niacin in human plasma by LC‐MS/MS and its application to a human pharmacokinetic study
Authors: Ravi Vasu Babu , Mullangi Ramesh , Inamadugu Jaswanth Kumar , Pilli Nageswara Rao , Gajula Ramakrishna , Ponneri Venkateswarlu
Published: March 2012

A rapid, simple, sensitive and selective LC‐MS/MS method has been developed and validated for quantification of the atorvastatin (AT) and niacin (NA) in 250 μL human plasma. The analytical procedure involves a liquid–liquid extraction method using nevirapine as an internal standard (IS). The chromatographic separation was achieved on a Hypurity Advance (4.6 × 50 mm, 5 µm) column using a mobile phase consisting of 0.1% formic acid buffer–acetonitrile (20:80, v/v) at flow rate of 0.8 mL/min. The API‐4000 LC‐MS/MS was operated in the multiple‐reaction monitoring mode using electrospray ionization. The total run time of analysis was 3 min and elution of AT, NA and IS occurred at 1.06, 1.84 and 0.92 min, respectively. A detailed validation of the method was performed as per the US Food and Drug Administration guidelines and the standard curves found to be linear in the range of 0.10–30.0 ng/mL for AT and 20.2–6026 ng/mL for NA, with a coefficient of correlation of ≥0.99 for both the compounds. AT and NA were found to be stable in a battery of stability studies, viz. bench‐top, autosampler, re‐injection, wet‐extract and repeated freeze–thaw cycles. The developed assay method was successfully applied to a pharmacokinetic study in humans. Copyright © 2012 John Wiley & Sons, Ltd.
Rapid‐exchange guide catheter extension for extending the reach of an AL3 guide in a patient with a long, dilated ascending aorta
Authors: Roth Gregory A. , Dean Larry S. , Don Creighton W.
Published: March 2012

We describe the use of a rapid‐exchange style guide catheter extension to facilitate diagnostic coronary angiography in a patient with a long, dilated ascending aorta. The guide catheter extension is an easy to use device that can extend the reach of 110 cm catheters. There are several advantages to this “mother and child” guide catheter extension over the traditional telescoping catheter approach. © 2012 Wiley Periodicals, Inc.
Angiographic investigation of the pathophysiology of perioperative myocardial infarction
Authors: Duvall W. Lane , Sealove Brett , Pungoti Chetan , Katz Daniel , Moreno Pedro , Kim Michael
Published: March 2012

Background: The study of the pathophysiologic mechanism of perioperative myocardial infarctions is limited to two small autopsy studies suggesting a major role for plaque rupture and thrombosis. However, the perioperative period is characterized by increased cardiac metabolic demand that may lead to infarction in patients with otherwise stable obstructive coronary artery disease. The purpose of this study is to investigate the pathophysiology of perioperative myocardial infarctions. Methods: Hospital records and coronary angiograms from patients from 1998 to 2006 who underwent noncardiac surgery complicated by a perioperative myocardial infarction (MI) were reviewed. The culprit lesion was identified based on ECG, left ventriculography, and coronary angiography. Degree of stenosis, TIMI flow, ACC thrombus grade, calcification score, and lesion morphology were evaluated. Based on these criteria, MIs were categorized as thrombotic, demand, or nonobstructive. Results: Sixty‐six patients (average age, 71 years and 44% male), 77% of whom underwent an intermediate risk surgery with a 2% perioperative mortality, were identified. The distribution of demand, thrombotic, and nonobstructive MI was 55%, 26%, and 19%, respectively. There was neither statistical difference in the occurrence of prolonged hypotension or tachycardia between groups nor was there any difference in the use of antiplatelets, β‐blockers, or statins. Conclusion: This study identified demand ischemia as the predominant etiology of perioperative MIs in this cohort. An improved understanding of the pathophysiologic mechanism of perioperative MIs may facilitate the evaluation and management of preoperative patients. © 2012 Wiley Periodicals, Inc.
Impact of three‐dimensional transesophageal echocardiography on prosthesis sizing for transcatheter aortic valve implantation
Authors: Husser Oliver , Rauch Simon , Endemann Dierk H. , Resch Markus , Nunez Julio , Bodi Vicente , Hilker Michael , Schmid Christof , Riegger Günter A.J. , Luchner Andreas , Hengstenberg Christian
Published: March 2012

Objectives: To compare aortic annulus diameters obtained by 3D transesophageal echocardiography (TEE) with 2D‐TEE and the impact on prosthesis size selection in transcatheter aortic valve implantation (TAVI). Background: In TAVI the aortic annulus diameter determines prosthesis size. The ideal modality for annulus assessment has not been defined yet. Methods: Annulus diameters in 2D‐TEE (long‐axis view) and in 3D‐TEE (long‐axis view in multiple‐plane‐reconstruction) were compared in consecutive patients with aortic stenosis screened for TAVI. Prosthesis size was selected according to industry guidelines, integrating data from 3D‐TEE, angiography and computed tomography. The percentage of cases in which 2D‐TEE and 3D‐TEE correctly predicted final prosthesis size was calculated. Results: Forty‐nine patients were studied (Age 80 ± 5, 39% male, logistic EuroScore 17 ± 11%). Annulus diameters from 2D‐ and 3D‐TEE correlated (r = 0.808, P < 0.0001). Mean diameters were significantly larger on 3D‐ vs. 2D‐TEE (23.4 ± 2.2 vs. 22.1 ± 2.6 mm, P < 0.001) with a mean difference of 1.2 mm (limits of agreement: −1.8 to 4.3). The interobserver variability of 2D‐ and 3D‐TEE was 3.5 ± 5.6% and 0.9 ± 5.1%, respectively. Thirty‐nine patients underwent TAVI (27 CoreValve™, 12 Edwards Sapien™). The procedure was successful in 37 (95%) patients. Postprocedural regurgitation was none or mild in 89% of the cases with no severe insufficiency. Final prosthesis size was correctly predicted by 2D‐TEE in 67% while in 80% by 3D‐TEE. Overall, 3D‐TEE suggested a different prosthesis size in 26% of all cases compared to 2D‐TEE. Conclusions: Aortic annulus measurement by 3D‐TEE yields significantly larger diameters than 2D‐TEE. This impacts prosthesis size selection in a considerable percentage of cases. © 2012 Wiley Periodicals, Inc.
Chronic kidney disease and the risk of stent thrombosis after percutaneous coronary intervention with drug‐eluting stents
Authors: Miao Yu , Yu‐Jie Zhou , Zhi‐Jian Wang , Dong‐Mei Shi , Yu‐Yang Liu , Ying‐Xin Zhao , Fei Gao , Shi‐Wei Yang , De‐An Jia
Published: March 2012

Background

Chronic kidney disease (CKD) has been demonstrated to be associated with adverse clinical outcomes for patients with coronary artery disease (CAD). However, data on relation of CKD and stent thrombosis (ST) after drug‐eluting stent (DES) implantation are limited.

Objectives

This study was designed to examine whether CKD is associated with higher incidence of ST after elective coronary DES implantation compared with patients with normal renal function.

Methods

We consecutively enrolled 2,862 patients undergoing elective percutaneous coronary intervention (PCI) with DES. Demographic and clinical data were collected preoperatively. CKD was defined as estimated glomerular filtration rate (eGFR) < 60 ml/min, calculated using the modified MDRD equation. The primary outcome was 1‐year definite or probable ST.

Results

Four hundred and forty‐five participants (15.5%) had CKD before procedure. The incidence of 1‐year definite or probable ST was significantly higher in CKD patients compared with patients with normal renal function (1.8% vs. 0.6%, P = 0.014). After adjustment for multiple clinical and biochemical covariates, CKD was an independent predictor of 1‐year definite or probable ST (hazard rate [HR] 0.396, 95% CI 0.165–0.951, P = 0.038).

Conclusion

CKD is significantly associated with increased incidence of 1‐year definite or probable ST in patients undergoing PCI with DES. © 2012 Wiley Periodicals Inc.
Magnetic Nanoparticles of Ferrite Complex Oxides: A Cheap, Efficient, Recyclable Catalyst for Building the CN Bond under Ligand‐Free Conditions
Authors: Zhang Rongzhao , Miao Chengxia , Shen Zhiqiang , Wang Shoufeng , Xia Chungu , Sun Wei
Published: March 2012

A series of magnetic nanoparticles of ferrite complex oxides were simply prepared by using a citric acid complex method and characterized by using XRD, FT‐IR spectroscopy, TEM, the BET nitrogen adsorption/desorption technique, and a vibrating sample magnetometer. The magnetic nanoparticles were used for the N‐arylation of nitrogen nucleophiles to form new CN bonds. CuFe2O4 nanoparticles calcined at 850 °C exhibited the best activity with moderate to excellent yields under ligand‐free conditions. Notably, CuFe2O4 is completely recoverable with an external magnet and can be reused eight times without significant loss of catalytic activity.
Kinetic Study of Spent Nickel Catalyst Dissolution in HCl and Aqua Regia Medium
Authors: Hosseini S. A. , Khalilzadeh M. A. , Jamshidi A.
Published: March 2012

The leaching kinetics of spent nickel oxide catalysts in HCl and aqua regia solution is described. The considered parameters affecting nickel recovery are particle size, reaction time, acid concentration, and reaction temperature. Nickel could be extracted with HCl by ∼87.41 % and with aqua regia by ∼81.01 % using a spent catalyst with 200 mesh particle size at a reaction temperature of 100 °C. The reaction time was 360 min and the concentrations of HCl and aqua regia were 37 % and 80 %, respectively. The leaching kinetics indicates that shrinking sphere and diffusion were the rate‐controlling processes during the reactions with HCl and aqua regia, respectively. The activation energies for HCl and aqua regia were determined as 24.04 and 19.03 kJ mol–1, respectively.
Experimental and Kinetic Studies on a Homogeneous System for Diethyl Carbonate Synthesis by Transesterification
Authors: Zhang Y. , Ji Z. , Xu R. , Fang Y.
Published: March 2012

A synthesis of diethyl carbonate through transesterification of propylene carbonate and ethanol, coproducing useful propylene glycol, was carried out in the presence of sodium ethoxide as catalyst. The effects of reaction parameters such as catalyst concentration, mole ratio of ethanol to propylene carbonate and reaction temperature on the transesterfication reaction were investigated. The results showed that the reaction is reversible with a propylene carbonate equilibrium conversion of about 64 % at an ethanol to propylene carbonate mole ratio of 8.0 and a reaction temperature of 303 K. A kinetic model was proposed based on the reaction mechanism. The model parameters were estimated by the Runge‐Kutta method. The statistical test showed that the model calculation results were in good agreement with the experimental data.
Online Monitoring of Vinyl Chloride Polymerization in a Microreactor Using Raman Spectroscopy
Authors: Dorobantu Bodoc M. , Prat L. , Xuereb C. , Gourdon C. , Lasuye T.
Published: March 2012

A novel capillary‐based microfluidic device has been designed to follow the vinyl chloride polymerization reaction. Monodisperse droplets of 200 μm diameter could be obtained by means of a co‐flow generation system, each one being considered as a polymerization reactor. Monomer droplets were visualized in a microchannel with a high‐speed camera. At the end of the reaction, PVC grains were observed with a scanning electron microscopy technique. Real‐time non‐invasive Raman measurement was performed on stationary vinyl chloride monomer droplets and provided values of effective reaction orders and rate constants. This microdevice allowed reaction investigation under difficult conditions of pressure and temperature with a minimal amount of reagents.
Nitrogen‐Doped Carbon Monolith for Alkaline Supercapacitors and Understanding Nitrogen‐Induced Redox Transitions
Authors: Wang Da‐Wei , Li Feng , Yin Li‐Chang , Lu Xu , Chen Zhi‐Gang , Gentle Ian R. , Lu Gao Qing (Max) , Cheng Hui‐Ming
Published: March 2012

A nitrogen‐doped porous carbon monolith was synthesized as a pseudo‐capacitive electrode for use in alkaline supercapacitors. Ammonia‐assisted carbonization was used to dope the surface with nitrogen heteroatoms in a way that replaced carbon atoms but kept the oxygen content constant. Ammonia treatment expanded the micropore size‐distributions and increased the specific surface area from 383 m2 g−1 to 679 m2 g−1. The nitrogen‐containing porous carbon material showed a higher capacitance (246 F g−1) in comparison with the nitrogen‐free one (186 F g−1). Ex situ electrochemical spectroscopy was used to investigate the evolution of the nitrogen‐containing functional groups on the surface of the N‐doped carbon electrodes in a three‐electrode cell. In addition, first‐principles calculations were explored regarding the electronic structures of different nitrogen groups to determine their relative redox potentials. We proposed possible redox reaction pathways based on the calculated redox affinity of different groups and surface analysis, which involved the reversible attachment/detachment of hydroxy groups between pyridone and pyridine. The oxidation of nitrogen atoms in pyridine was also suggested as a possible reaction pathway.
ChemInform Abstract: Highly Enantioselective Michael Addition of Ketones to Nitroolefins with a Pyrrolidine‐Based Phthalimide as an Enamine‐Type Organocatalyst.
Authors: Ban Shu‐rong , Xie Hong‐yu , Zhu Xi‐xia , Li Qing‐shan
Published: March 2012

A new N‐(pyrrolidinylmethyl)phthalimide organocatalyst is successfully applied in the Michael addition reaction of nitroolefins towards cyclohexanone (I).
ChemInform Abstract: Co(I)‐ versus Ru(II)‐Catalyzed [2 + 2 + 2] Cycloadditions Involving Alkynyl Halides.
Authors: Iannazzo Laura , Kotera Naoko , Malacria Max , Aubert Corinne , Gandon Vincent
Published: March 2012

While Ru catalysts remain the best choice for [2 + 2 + 2] cycloaddition reactions of alkynyl chlorides and iodides, the cheap air‐stable cobalt complex under certain conditions proves efficient with alkynyl bromides.
ChemInform Abstract: N‐Heterocyclic Carbene Based Ruthenium‐Catalyzed Direct Amide Synthesis from Alcohols and Secondary Amines: Involvement of Esters.
Authors: Chen Cheng , Zhang Yao , Hong Soon Hyeok
Published: March 2012

The Ru‐complex in combination with KOtBu efficiently promotes the coupling of alcohols with secondary amines.
ChemInform Abstract: First Nucleophilic Addition of Acetylide to 1,3‐Diketonate Anions: Reaction of 1‐Aryl‐4,4,4‐trifluorobutane‐1,3‐diones with Sodium Acetylide.
Authors: Usachev Boris I.
Published: March 2012

Regioselective nucleophilic addition affords alkyne diols (III) which are converted into bisfurans (IV) via a novel double cyclization.
ChemInform Abstract: Palladium‐Catalyzed C—C Bond Formation of Arylhydrazines with Olefins via Carbon—Nitrogen Bond Cleavage.
Authors: Zhu Ming‐Kui , Zhao Jun‐Feng , Loh Teck‐Peng
Published: March 2012

The unactivated C—N bond of various aryl hydrazines (I), (IV), (VII), and (X) is cleaved under mild conditions by Pd(0) with the assistance of Pd(II).
ChemInform Abstract: Synthesis of Biaryls via AlCl3 Catalyzed Domino Reaction Involving Cyclization, Dehydration, and Oxidation.
Authors: Narender Tardigoppula , Sarkar Satinath , Rajendar Kandikonda , Tiwari Sriniwas
Published: March 2012

A novel method for the synthesis of biaryls (IV) and (VII) is elaborated using a prenylation reaction of aromatic ketones (I) and (V) and a subsequent AlCl3‐catalyzed domino reaction of resulting prenylated ketones (III) and (VI) respectively.
ChemInform Abstract: Catalytic Asymmetric Construction of Spirocyclopentaneoxindoles by a Combined Ru‐Catalyzed Cross‐Metathesis/Double Michael Addition Sequence.
Authors: Li Ying‐Mei , Li Xiang , Peng Fang‐Zhi , Li Ze‐Qian , Wu Shou‐Tao , Sun Zhong‐Wen , Zhang Hong‐Bin , Shao Zhi‐Hui
Published: March 2012

The ruthenium‐catalyzed cross‐metathesis of 3‐allyloxindoles (I) with ethyl acrylate followed by an asymmetric double‐Michael addition reaction of resulting oxindoles (III) with nitroolefins (IV) provides access to spirocyclopentaneoxindoles (V) with high diastereo‐ and enantioselectivity.
ChemInform Abstract: An Efficient and Convenient Approach for the Synthesis of Novel 2‐Hydroxy‐12‐aryl‐8,9,10,12‐tetrahydrobenzo[a]xanthene‐11‐ones Using p‐Toluenesulfonic Acid in Ethanol and Ionic Liquid.
Authors: Khurana Jitender M. , Nand Bhaskara , Sneha Sneha
Published: March 2012

The presented method is operationally convenient, gives excellent yields of the title compounds in high purity with easy work‐up.
ChemInform Abstract: New Spirocyclic Δ2‐Isoxazoline Derivatives Related to Selective Agonists of α7 Neuronal Nicotinic Acetylcholine Receptor.
Authors: Dallanoce Clelia , et al. et al.
Published: March 2012

Compounds (VI) and (XIV) exhibit an equal binding affinity in the nanomolar range at the α7 nAChRs as the reference compounds.
ChemInform Abstract: Catalysis Based on Nanocrystals with Well‐Defined Facets
Authors: Zhou Kebin , Li Yadong
Published: March 2012

Review: 79 refs.
ChemInform Abstract: N‐(Phosphonomethyl)iminodiacetic Acid in the Construction of Coordination Polymers
Authors: Almeida Paz Filipe A. , Rocha Joao
Published: March 2012

Review: 70 refs.
ChemInform Abstract: Polymorph Prediction of Small Organic Molecules, Co‐crystals and Salts
Authors: Leusen Frank J. J. , Kendrick John
Published: March 2012

Review: 130 refs.
Methodical Approaches to Experimental Investigations on Surface Filtration using Flexible Filter Media on a Standard Laboratory Filter Test Rig
Authors: Zhang Qian , Schmidt Eberhard
Published: March 2012

Die Partikelabscheidung aus Gasen mit Oberflächenfiltern ist sowohl bei der Emissionsminderung als auch bei der Wertstoffgewinnung ein bewährtes Standardverfahren. Experimentelle Untersuchungen zur Oberflächenfiltration werden häufig mit Testfiltern, die an Filteranlagen im Labormaßstab eingebaut sind, durchgeführt. Am Beispiel einer bekannten genormten Labor‐Filterprüfapparatur werden Ansatzpunkte zum methodischen Vorgehen bei experimentellen Untersuchungen zur Oberflächenfiltration mit flexiblen Filtermedien beschrieben und diskutiert, die einen schlüssigen quantitativen Vergleich der experimentellen Ergebnisse ermöglichen bzw. erleichtern sollen.
Impact of density gradients on the fluid flow inside a vibrating cavity subjected to soret effect
Authors: Parsa Aram , Srinivasan Seshasai , Saghir M. Ziad
Published: March 2012

Computational fluid dynamics simulations of thermovibrational flows in a square cavity filled with a water–isopropanol mixture has shown that inaccurate density calculations can predict very different flow behaviours. Specifically, comparison has been made between two density calculation models, viz., a weighted‐average scheme and the Perturbed Chain Statistical Associating Fluid Theory equation of state. While the latter approach predicts a stronger flow in the cavity due to the convective instabilities that are induced by the large spatial gradients in density, the weighted‐average scheme cannot predict this since it does not explicitly depend on the temperature of the mixture. © 2012 Canadian Society for Chemical Engineering
The Binding of a Hydroxy‐9,10‐anthraquinone CuII Complex to Calf Thymus DNA: Electrochemistry and UV/Vis Spectroscopy
Authors: Guin Partha S. , Mandal Parikshit C. , Das Saurabh
Published: March 2012

Anthracyclines are broad‐spectrum antibiotics that are used against several human cancers. Hydroxy‐9,10‐anthraquinone compounds closely resemble anthracycline antibiotics from a structural and functional viewpoint. High cost and aspects of toxicity introduce limitations on its use. On complex formation the toxicities of anthracyclines decrease. A close analogue is sodium 1,4‐dihydroxy‐9,10‐anthraquinone‐2‐sulphonate (AS), which is a comparatively cheaper molecule and resembles a good number of anthracycline derivatives. It forms a complex with CuII, [Cu(AS)2]. The complex interacts with calf thymus DNA that was studied by UV/Vis spectroscopy and cyclic voltammetry. The experimental data obtained from the two techniques was analyzed for binding constant and size of the binding site. These results not only corroborate each other but also justify earlier data obtained using fluorescence spectroscopy. An important aspect to this study was that nonlinear curve fitting, which is usually applied for analyzing DNA interaction using fluorescence and absorption spectroscopy, was used for the first time to analyze the interaction of the complex with DNA using cyclic voltammetry by monitoring the change in the reduction peak current (Ip). The DNA binding data provides an insight into a probable mode of action of the hydroxy‐9,10‐anthraquinones within cells as modification of DNA that leads to cell death is an important aspect in cancer research.
An indicator kriging method for distributed estimation in wireless sensor networks
Authors: Liu Guiyun , Xu Bugong , Chen Hongbin
Published: March 2012

The problem of distributed estimation in a wireless sensor network with unknown observation noise distribution is investigated, where each sensor only sends quantized data to a fusion center. The sensing field is modeled as a spatially random field. The objective was to accurately estimate a hidden parameter at the location where no sensor exists, while minimizing the total energy consumption. Driven by the lack of a prior knowledge of the sensing field and the existence of some outliers, an indicator kriging estimator is developed for distributed estimation under imperfect communication channels between the sensors and the fusion center. The tradeoff between estimation performance and energy consumption is formulated as an optimization problem, and a global search algorithm is proposed to approximate the solution. The results show that the proposed indicator kriging estimator achieves better performance than the inverse distance estimator and the simple averaging estimator. Moreover, the proposed search algorithm can schedule the sensors to reach the tradeoff. Copyright © 2012 John Wiley & Sons, Ltd.
The expression profile of the tumor suppressor gene Lzts1 suggests a role in neuronal development
Authors: Kropp Marlene , Wilson Sara I.
Published: March 2012

Background: Neuronal circuit assembly comprises a number of developmental processes that ultimately underlie function. Identifying the molecular events that dictate these processes can give key insights into how neuronal circuit formation is coordinated. To begin to identify such molecular mechanisms, we have analysed the expression of a candidate gene of entirely unknown function within the nervous system. Here we reveal the spatial and temporal distribution of Lzts1 in mouse and chick embryonic spinal cord and propose potential biological functions. Results: Lzts1 mRNA is transiently expressed at the border of the ventricular and mantle zones in subsets of sensory and motor spinal neurons. The protein is localized to the cell body, axon, and trailing process of motor, commissural, and dorsal root neurons during development. Conclusions: Taken together, the spatial and temporal distribution of Lzts1 is consistent with a potential function(s) in cell cycle regulation, axon growth or guidance, and/or migration of neurons. Developmental Dynamics 241:984–994, 2012. © 2012 Wiley Periodicals, Inc.
Egg incubation temperature differently affects female and male hatching dynamics and larval fitness in a leafhopper
Authors: Chuche Julien , Thiéry Denis
Published: March 2012

Temperature effects on ectotherms are widely studied particularly in insects. However, the life‐history effects of temperature experienced during a window of embryonic development, that is egg stage, have rarely been considered. We simulated fluctuating temperatures and examined how this affects the operational sex ratio (OSR) of hatching as well as nymph and adult fitness in a leafhopper, Scaphoideus titanus. Specifically, after a warm or cold incubation we compared males and females hatching dynamics with their consequences on the sex ratio in the course of time, body size, weight, and developmental rate of the two populations, all reared on the same posthatching temperature. Males and females eggs respond differently, with females more sensitive to variation in incubation temperature. The different responses of both sexes have consequences on the sex ratio dynamic of hatchings with a weaker protandry after warm incubation. Temperatures experienced by eggs have more complex consequences on posthatching development. Later nymphal instars that hatched from eggs exposed to warm temperature were larger and bigger but developmental rate of the two populations was not affected. Our study demonstrates how incubation temperature could affect operational sex ratio and posthatching development in an insect and how this may be critical for population growth.
Dialkyl Rare Earth Complexes Supported by Potentially Tridentate Amidinate Ligands: Synthesis, Structures, and Catalytic Activity in Isoprene Polymerization
Authors: Rad'kov Vassily Yu. , Skvortsov Grigorii G. , Lyubov Dmitry M. , Cherkasov Anton V. , Fukin Georgy K. , Shavyrin Andrei S. , Cui Dongmei , Trifonov Alexander A.
Published: March 2012

Two new amidines that contain a pendant Lewis base in the side arm, 2‐MeOC6H4NC(tBu)NH(2,6‐R2C6H3) (R = Me, iPr), were synthesized and successfully employed as tridentate ligands for the preparation of the dialkyl rare earth complexes [2‐MeOC6H4NC(tBu)N(2,6‐R2C6H3)]Ln(CH2SiMe3)2(L)n {Ln = Y, Lu; R = Me, iPr; L = thf (n = 2), dme (n = 1)}. These ligands provided enhanced stability for the complexes. The X‐ray structure determinations revealed that intramolecular coordination of the 2‐MeOC6H4 group is realized if a thf molecule is coordinated to the metal center (Ln = Y, Lu), which results in the coordination number of six. The treatment of complex [2‐MeOC6H4NC(tBu)N(2,6‐Me2C6H3)]Lu(CH2SiMe3)2(thf) with dme afforded a six‐coordinate dme adduct in which the methoxy group of the amidinate ligand has drifted out from the metal coordination sphere. The reaction of [2‐MeOC6H4NC(tBu)N(2,6‐iPr2C6H3)]Y(CH2SiMe3)2(thf) with 2,6‐diisopropylaniline in hexane at –70 °C, regardless of the ratio of the reagent, afforded the six‐coordinate diamido compound [2‐MeOC6H4NC(tBu)N(2,6‐iPr2C6H3)]Y(NHC6H3‐2,6‐iPr2)2(thf), for which intramolecular coordination of the oxygen atom of the side chain was detected by an X‐ray study. Complex [2‐MeOC6H4NC(tBu)N(2,6‐iPr2C6H3)]Y(CH2SiMe3)2(thf) was evaluated as a precatalyst for isoprene polymerization. The ternary system [2‐MeOC6H4NC(tBu)N(2,6‐iPr2C6H3)]Y(CH2SiMe3)2(thf)/[Ph3C][B(C6F5)4]/AliBu3provided isoprene polymerization with moderate activity but without control of the regioselectivity (3,4‐regularity was slightly predominant at 52 %). Nevertheless, high 1,4‐trans‐selectivity was found (96 %) for the 1,4‐polyisoprenes. The obtained polyisoprene has a Mn of 13.0 × 104 and moderate polydispersity (2.12).
[n]Borametalloarenophanes (n = 1, 2): Strained Systems with Uncommon Reactivity PatternsUnexpected Outcomes of the Oxidation of (Pentafluorophenyl)triphenylphosphanegold(I)The Question of cis versus trans Configuration in Octahedral Metal Diketonates: An In‐Depth Investigation on Diorganobis(4‐acyl‐5‐pyrazolonato)tin(IV) Complexes Chelating C4‐Bound Imidazolylidene Complexes through Oxidative Addition of Imidazolium Salts to Palladium(0) Ruthenium Acetate Complexes as Versatile Probes of Metal–Ligand Interactions: Insight into the Ligand Effects of Vinylidene, Carbene, Carbonyl, Nitrosyl and Isocyanide (Eur. J. Inorg. Chem. 9/2012)
Authors: Braunschweig Holger , Nevado Cristina , Hanna John V. , Marchetti Fabio , Pettinari Claudio , Albrecht Martin , Lynam Jason M.
Published: March 2012

The back cover picture comprises the contributions of Holger Braunschweig et al. (borametalloarenophanes), Cristina Nevado et al. (arylgold complexes), John V. Hanna, Fabio Marchetti, Claudio Pettinari et al. (organotin reagents), Martin Albrecht et al. (palladium–NHC compounds), and Jason M. Lynam et al. (ruthenium complexes), highlighting the variety of content from uncommon reactivity and unusual compounds to electronic properties. Thanks are due to these groups for providing the graphic designs that make up this cover.
Pin‐supported walls for enhancing the seismic performance of building structures
Authors: Qu Zhe , Wada Akira , Motoyui Shojiro , Sakata Hiroyasu , Kishiki Shoichi
Published: March 2012

An application of a pin‐supported wall‐frame system in retrofitting an eleven‐story steel reinforced concrete frame is introduced. The retrofit aims at enhancing integrity and avoiding weak story failure in an existing moment‐resisting frame. Seismic performance of the building before and after the retrofit is assessed through nonlinear dynamic analysis. The results show that the pin‐supported walls are effective in controlling the deformation pattern of the ductile frame and hence in avoiding weak story failure. With the well‐controlled deformation pattern, carefully arranged energy dissipating devices are able to concentrate energy dissipations so that damage to the rest of the structure can be significantly reduced. Copyright © 2012 John Wiley & Sons, Ltd.
Performance Evaluation and Parametric Optimization of a Proton Exchange Membrane Fuel Cell/heat‐driven Heat Pump Hybrid System
Authors: Zhang X. , Chen J.
Published: March 2012

With the help of the current models of proton exchange membrane (PEM) fuel cells and three‐heat‐source heat pumps, a generic model of a PEM fuel cell/heat‐driven heat pump hybrid system is established, so that the waste heat produced in the PEM fuel cell may be availably utilized. Based on the theory of electrochemistry and non‐equilibrium thermodynamics, expressions for the efficiency and power output of the PEM fuel cell, the coefficient of performance and rate of pumping heat of the heat‐driven heat pump, and the equivalent efficiency and power output of the hybrid system are derived. The curves of the equivalent efficiency and power output of the hybrid system varying with the electric current density and the equivalent power output versus efficiency curves are represented through numerical calculation. The general performance characteristics of the hybrid system are analyzed. The optimally operating regions of some important parameters of the hybrid system are determined. The influence of some main irreversible losses on the performance of the hybrid system is discussed in detail. The advantages of the hybrid system are revealed.
Pd/Co Bimetallic Nanoparticles: Coelectrodeposition under Protection of PVP and Enhanced Electrocatalytic Activity for Ethanol Electrooxidation
Authors: Yang Z.‐S. , Wu J.‐J.
Published: March 2012

A series of Pd–Co bimetallic nanostructures with Co compositions ranging from 0 to 13 at.% were fabricated on glassy carbon electrode by one step electrodeposition in the presence of polyvinylpyrrolidone (PVP). The roles of PVP and Co have been systematically investigated by using combined techniques such as scanning electron microscopy, energy dispersive spectrometry, cyclic voltammetry, X‐ray diffraction, and chronoamperograms. PVP was used as an additive to stabilize the Pd nanoparticles and inhibit agglomeration during their formation. The prepared Pd100Co10 bimetallic nanostructures exhibited great catalytic activity towards ethanol oxidation in alkaline, which implies that low Co doping can be a convenient way to enhance the electrocatalytic property of Pd. The present study shows that the Pd/Co bimetallic nanoparticulate can be a promising catalyst for portable applications in direct ethanol fuel cell in alkaline solution.
Morphogenesis of the human laryngeal ventricles
Authors: Viejo Fermín , Pascual‐Font Arán , Rivas Luis , Hernández‐Morato Ignacio , Vázquez Teresa , Rodriguez‐Niedenführ Marc , McHanwell Stephen , Sanudo José R.
Published: March 2012

Background

Two theories explain the origin of human laryngeal ventricles: (1) ventricles derive from the fifth pharyngeal pouches; (2) development independent from the pouches.

Methods

In all, there were 21 serially sectioned human embryos from stages 15 to 23, and 11 fetuses of 9 to 18 weeks. Computer‐aided 3‐dimentional reconstructions were made.

Results

The cranial part of the laryngeal sulcus and future vestibule expands from the pharyngeal floor between the third and fourth pharyngeal pouches during stages 15 and 16 (33–37 days). The primordia of the ventricles appeared at stage 18 (44 days) as 2 lateral swellings in the caudal end of the future vestibule, limited by the third pharyngeal pouches. Active epithelial expansion and subsequent canalization during late embryonic and early fetal periods finalizes their development.

Conclusions

The laryngeal ventricles do not derive from the pharyngeal pouches but the median region of the pharyngeal floor between the third and fourth pharyngeal pouches and arches at the caudal end of the future vestibule. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Hippocampal theta‐driving cells revealed by Granger causality
Authors: Zhang Lu , Chen Guifen , Niu Ruifang , Wei Wei , Ma Xiaoyu , Xu Jiamin , Wang Jingyi , Wang Zhiru , Lin Longnian
Published: March 2012

The two‐dipole model of theta generation in hippocampal CA1 suggests that the inhibitory perisomatic theta dipole is generated by local GABAergic interneurons. Various CA1 interneurons fire preferentially at different theta phases, raising the question of how these theta‐locked interneurons contribute to the generation of theta oscillations. We here recorded interneurons in the hippocampal CA1 area of freely behaving mice, and identified a unique subset of theta‐locked interneurons by using the Granger causality approach. These cells fired in an extremely reliable theta‐burst pattern at high firing rates (∼90 Hz) during exploration and always locked to ascending phases of the theta waves. Among theta‐locked interneurons we recorded, only these cells generated strong Granger causal influences on local field potential (LFP) signals within the theta band (4–12 Hz), and the influences were persistent across behavioral states. Our results suggest that this unique type of theta‐locked interneurons serve as the local inhibitory theta dipole control cells in shaping hippocampal theta oscillations. © 2012 Wiley Periodicals, Inc.
Persistence of resinous cement residues in dentin treated with different chemical removal protocols
Authors: Kuga Milton Carlos , Só Marcus Vinicius Reis , De Faria‐júnior Norberto Batista , Keine Kátia Cristina , Faria Gisele , Fabricio Semíramis , Matsumoto Mariza Akemi
Published: March 2012

The aim of this study was to evaluate the persistence of resin cement residues after dentin surface cleaning with different alcohol‐based solutions or an essential oil (eucalyptol). Forty bovine teeth were sectioned in order to expose pulp chamber dentin to be washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% EDTA application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin‐based cement was rubbed onto the dentine surface with a microbrush applicator. After 15 min, the surface was scrubbed with a cotton pellet and moistened with different dentin cleaning solutions, compounding the following groups: G1—95% ethanol, G2—70% ethanol, G3—70% isopropyl alcohol, or G4—eucalyptol. The dentin was scrubbed until the cement residues could not be visually detected. Sections were then processed for SEM and evaluated at ×500 magnification. Scores were attributed to each image according to the area covered by residual sealer, and data were subjected to Kruskal–Wallis at 5% significance. Eucalyptol promoted the most adequate dentin cleaning, although no statistical difference was detected amongst the groups (P > 0.05), except between the eucalyptol and 70% ethanol groups (P < 0.05). All the evaluated dentin cleaning solutions were unable to completely remove the cement residues from the dentin surface. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
Virus present in the reproductive tract of asymptomatic drones of honey bee (Apis mellifera l.), and possible infection of queen during mating
Authors: Da Cruz‐Landim Carminda , Roat Thaisa C. , Fernadez Fernanda C.
Published: March 2012

Virus particles and viral inclusions were detected by transmission electron microscopy examination of sections of the seminal vesicles and mucus gland of asymptomatic young drones from colonies of Apis mellifera lightly infested by Varroa mite. In the mucus gland the infection was found in the muscular sheath and epithelium, while in the seminal vesicle in cells of the outer serosa. Isolated viral particles were also observed in the hemolymph occupying the intercellular spaces of the muscular sheath fibers. In the muscle the virus appeared as polygonal crystalloid inclusions, while in the epithelium mainly inside cytoplasmic vesicles. The infected cells apparently are not damaged. The virus particles are present in the hemolymph and forming more mature structures, as crystalloids, in the muscle. This suggests that the virus is liberated in the body fluid and infects the tissues penetrating the cells through endocytosis. The presence of virus in mucus gland epithelial vesicles raise the possibility of its transference to the gland secretion and therefore, to the semen. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
An Asymptotic Version of the Multigraph 1‐Factorization Conjecture
Authors: Vaughan E. R.
Published: March 2012

We give a self‐contained proof that for all positive integers r and all , there is an integer such that for all any regular multigraph of order 2n with multiplicity at most r and degree at least is 1‐factorizable. This generalizes results of Perković and Reed (Discrete Math 165/166 (1997), 567–578) and Plantholt and Tipnis (J London Math Soc 44 (1991), 393–400).
Alternative efficient tritium labeling of repaglinide
Authors: Vliegen Maarten , Haspeslagh Pieter , Verluyten Willy
Published: March 2012

There is a need for an efficient tritium labeling methodology for repaglinide to support numerous in vitro and in vivo studies. Numerous homogeneous and heterogeneous catalysts were screened for their capacity to tritiate repaglinide directly without the need to synthesize suitable precursors and to avoid multistep synthesis. In particular, boosting effects using a combination of homogeneous and heterogeneous catalysts were examined. Finally, a suitable method was selected for tritation and resulted in an efficient tritation of repaglinide via a heterogeneous catalyzed hydrogen–tritium exchange reaction with iridium black as the preferred catalyst.
Raman labeled nanoparticles: characterization of variability and improved method for unmixing
Authors: Kode Kranthi , Shachaf Cathy , Elchuri Sailaja , Nolan Garry , Paik David S.
Published: March 2012

Raman spectroscopy can differentiate the spectral fingerprints of many molecules, resulting in potentially high multiplexing capabilities of Raman‐tagged nanoparticles. However, an accurate quantitative unmixing of Raman spectra is challenging because of potential overlaps between Raman peaks from each molecule, as well as slight variations in the location, height, and width of very narrow peaks. If not accounted for properly, even minor fluctuations in the spectra may produce significant error that will ultimately result in poor unmixing accuracy. The objective of our study was to develop and validate a mathematical model of the Raman spectra of nanoparticles to unmix the contributions from each nanoparticle allowing simultaneous quantitation of several nanoparticle concentrations during sample characterization. We developed and evaluated an algorithm for quantitative unmixing of the spectra called narrow peak spectral algorithm (NPSA). Using NPSA, we were able to successfully unmix Raman spectra of up to seven Raman nanoparticles after correcting for spectral variations of 30% intensity and shifts in peak locations of up to 10 cm−1, which is equivalent to 50% of the full width at half maximum (FWHM). We compared the performance of NPSA to the conventional least squares (LS) analysis. Error in the NPSA is approximately 50% lower than in the LS. The error in estimating the relative contributions of each nanoparticle with the use of the NPSA are in the range of 10–16% for equal ratios and 13–19% for unequal ratios for the unmixing of seven composite organic–inorganic nanoparticles (COINs); whereas, the errors from using the traditional LS approach were in the range of 25–38% for equal ratios and 45–68% for unequal ratios. Here, we report for the first time the quantitative unmixing of seven nanoparticles with a maximum root mean square of the percentage error (RMS%) error of less than 20%. Copyright © 2012 John Wiley & Sons, Ltd.
Physical and sensory characteristics of cookies prepared with flaxseed flour
Authors: Khouryieh Hanna , Aramouni Fadi
Published: March 2012

BACKGROUND: Flaxseed has many health benefits and is considered a functional food ingredient. Flaxseed flour (0–18%) was used to partially replace wheat flour in cookies and its effects on the physical and sensory characteristics of the cookies were investigated. A correlation analysis was conducted between the instrumental and sensory data.

RESULTS: The cookie dough stickiness significantly (P < 0.05) decreased in relation to higher percentages of flaxseed flour. The 18% flaxseed cookies had the firmest texture, darkest color and lowest water activity. The 18% flaxseed cookies had the greatest spread ratio. However, this resulted in cookies of unacceptable quality properties. In consumer acceptance tests, cookies made with 6% and 12% flaxseed flour had the highest rating among all sensory attributes, while the 18% flaxseed cookies had the lowest sensory scores. The flavor attribute was most highly correlated with the overall acceptability (r = 0.90).

CONCLUSION: Results indicated that flaxseed flour can be incorporated in cookies as a partial replacement up to 12% of wheat flour without negatively affecting the physical and sensory quality. The correlation results suggest that the flaxseed flavor attributes best predict consumer preference for overall acceptability, though texture and color attributes also contribute. Copyright © 2012 Society of Chemical Industry
‘Fagiolo a Formella’, an Italian lima bean ecotype: biochemical and nutritional characterisation of dry and processed seeds
Authors: Piergiovanni Angela R , Sparvoli Francesca , Zaccardelli Massimo
Published: March 2012

BACKGROUND: An ecotype of the lima bean, named ‘fagiolo a Formella’, which, to the best of our knowledge, is the only example of an Italian lima bean (Phaseolus lunatus L.) ecotype, is cultivated in the Campania region of southern Italy. Physical, nutritional and processing traits of dry seeds were evaluated for two consecutive growing seasons (2009 and 2010). The canning quality was also investigated, but only for the harvest of 2010.

RESULTS: Sodium dodecyl sulfate–polyacrylamide gel electrophoresis of total seed proteins allowed the attribution of ‘fagiolo a Formella’ to the Mesoamerican gene pool and Sieva morphotype. Seeds have a trapezoid shape, white coat and 100‐seed weight greater than 42 g. Yield, protein, trypsin inhibitor and phytic acid values were found comparable with those reported for lima bean varieties cultivated in sub‐tropical areas. Moreover, we found that this ecotype is devoid of lectin.

CONCLUSIONS: The good adaptation to growing environment is indicated by the fact that ‘fagiolo a Formella’ seed quality is comparable to that of lima beans grown in America. Overall the canning quality was found satisfactory and canning significantly destroys the main anti‐nutritional compounds present in dry seeds. Copyright © 2012 Society of Chemical Industry