bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal stabilization of psychrophilic enzymes: A case study of the cold‐active hormone‐sensitive lipase from Psychrobacter sp. TA144
Authors: De Santi Concetta , Durante Lorenzo , Vecchio Pompea Del , Tutino Maria Luisa , Parrilli Ermenegilda , de Pascale Donatella 
Published: June 2012

AbstractCold‐adapted enzymes possess high specific activity at low and moderate temperatures with respect to their mesophilic and thermophilic homologs; it is accepted that they have a less rigid and more flexible structure in the region surrounding the active site. However, the low stability of such molecules could represent the main barrier for their application in some industrial bioprocesses. The aim of this article was to investigate the ability of the naturally occurring osmolytes to increase the thermal stability and the specific activity of the cold‐active lipase from Psychrobacter sp. TA144 (PsyHSL), which belongs to the hormone‐sensitive lipase group. The effect of trimethylamine N‐oxide (TMAO), betaine, and L‐proline addition on the activity and thermal stability of PsyHSL was investigated by means of biochemical and biophysical techniques. It turned out that in the presence of 3 M TMAO, the enzyme specific activity enhanced up to 250% at 50°C, while the addition of 1 M TMAO increased the thermostability fivefold at 45°C. Our experiments demonstrated that, even in the case of a psychrophilic enzyme, osmoprotectants, particularly TMAO, addition may be considered an efficient strategy to improve the protein thermal stability and specific activity at higher temperatures. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 28: 946–952, 2012
Energy, wealth, and human development: Why and how biomass pretreatment research must improve
Authors: Dale Bruce E. , Ong Rebecca G. 
Published: June 2012

AbstractA high level of human development is dependent on energy consumption (roughly 4 kW per person), and most developed countries that have reached this level have done so through the extensive use of fossil energy. However, given that fossil resources are finite, in order for developed countries to maintain their level of development and simultaneously allow developing countries to reach their potential, it is essential to develop viable renewable energy alternatives. Of particular importance are liquid fuel replacements for petroleum, the fossil resource that primarily drives commerce and economic growth. The intent of this article is to remind our fellow biofuel researchers, particularly those involved in lignocellulosic pretreatment, of these global issues and the serious nature of our work. We hope that this will inspire us to generate and report higher quality and more thorough data than has been done in the past. Only in this way can accurate comparisons and technoeconomic evaluations be made for the many different pretreatment technologies that are currently being researched. The data that primarily influence biorefinery economics can be subdivided into three main categories: yield, concentration, and rate. For these three categories we detail the specific data that should be reported for pretreatment research. In addition, there is other information that is needed to allow for a thorough comparison of pretreatment technologies. An overview of these criteria and our comparison of the current state of a number of pretreatment technologies with respect to these criteria are covered in the last section. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 28: 893–898, 2012
Melody transcatheter pulmonary valve implantation. Results from the registry of the Italian society of pediatric cardiology
Authors: Butera Gianfranco , Milanesi Ornella , Spadoni Isabella , Piazza Luciane , Donti Andrea , Ricci Christian , Agnoletti Gabriella , Pangrazi Alberta , Chessa Massimo , Carminati Mario 
Published: June 2012

Background and aimsPercutaneous implantation of pulmonary valve has been recently introduced in the clinical practice. Our aim was to analyze data of patients treated in Italy by using the Melody Medtronic valve.MethodsProspective, observational, multi‐centric survey by means of a web‐based database registry of the Italian Society of Pediatric Cardiology (SICP).ResultsBetween October 2007 and October 2010, 63 patients were included in the registry (median age: 24 years; range 11–65 years). Forty subjects were in NYHA class I–II while 23 were in NYHA class III–IV. Patients included had a history of a median three previous surgeries (range 1–5) and a median of one previous cardiac catheterization (range 0–4). A cono‐truncal disease was present in 39 patients, previous Ross operation in 9, and other diagnosis in 15. Indication to valve implantation was pure stenosis in 21 patients, pure regurgitation in 12, association of stenosis and regurgitation in 30. Implantation was performed in 61 subjects (97%). Pre‐stenting was performed in 85% of cases. Median procedure time was 170 minutes (range 85–360). No significant regurgitation was recorded after procedure while the trans‐pulmonary gradient reduced significantly. Early major complications occurred in seven subjects (11%). One death occurred in the early post‐operative period in a severely ill subject. At a median follow‐up of 30 months (range 12–48 months), three patients died due to underlying disease. Major complications occurred in six patients during follow‐up (external electric cardioversion: one patient; herpes virus encephalitis: two patients; Melody valve endocarditis needing surgical explant: two patients; major fractures of the stent and need second Melody valve implantation: two patients). Freedom from valve failure at latest follow‐up was 81.4% ± 9%.ConclusionEarly results of the SICP registry on transcatheter Melody pulmonary valve implantation show that the procedure is safe and successful. Major concerns are related to the occurrence of stent fracture and bacterial endocarditis. Longer follow‐up and larger series are needed. © 2012 Wiley Periodicals, Inc.
Octupolar Merocyanine Dyes: A New Class of Nonlinear Optical Chromophores
Authors: Poronik Yevgen M. , Hugues Vincent , Blanchard‐Desce Mireille , Gryko Daniel T. 
Published: June 2012

AbstractA set of new octupolar merocyanine chromophores was designed and synthesized. These compounds were prepared from the reaction of 1,3,5‐triformyl‐2,4,6‐trihydroxybenzene with heterocyclic nucleophiles. Octupolar dyes were formed exclusively in their open‐dye form. The one‐ and two‐photon‐absorption spectra of the dyes consist of two bands: The long‐wavelength band in the two‐photon absorption spectrum (a few hundreds GM above 1000 nm) matches well with the intense, long‐wavelength‐absorption band that is located in the visible region in the linear spectrum. Interestingly, an additional, much‐more‐intense TPA band in the NIR region is observed at higher energy, which corresponds to a weakly allowed one‐photon electronic transition. Changing the peripheral heterocyclic moieties allows tuning of the optical properties to approach the cyanine limit (i.e., polymethine state), thus resulting in a red‐shift of the low‐energy one‐photon‐absorption band as well as to the rise of an intense two‐photon‐absorption band in the NIR region. To the best of our knowledge, this is the first synthesis and TPA characterization of octupolar merocyanine chromophores with typical low‐bond‐length alternation.
Can Chiroptical Spectroscopy be Used for the Analysis of Blood Plasma?
Authors: Tatarkovič Michal , Fišar Zdeněk , Raboch Jiří , Jirák Roman , Setnička Vladimír 
Published: June 2012

ABSTRACTAs an improvement on currently used methods of molecular spectroscopy, we used chiroptical techniques (electronic circular dichroism, fluorescence detected circular dichroism, and Raman optical activity [ROA]) to investigate the human blood plasma. To avoid the degradation of plasma samples, we measured them directly without any further preparation. We also tested cutoff weight filters (Amicon Ultra 100, 30, 10, and 3 kDa by Merck Millipore) to reduce undesirable fluorescence in the ROA and Raman spectra and also to remove the most abundant protein in the plasma—human serum albumin. The obtained spectra show that the ultrafiltration has a positive effect on undesirable fluorescence in ROA and Raman and also could reduce the amount of albumin in the plasma. Our results suggest that blood plasma can be successfully measured by the aforementioned methods. Therefore, these methods can potentially be useful for following research in the development of new, noninvasive, and reliable screening methods of clinical diagnostics. Chirality 24:951–955, 2012. © 2012 Wiley Periodicals, Inc.
Stereoselective Binding of Flurbiprofen Enantiomers and their Methyl Esters to Human Serum Albumin Studied by Time‐Resolved Phosphorescence
Authors: Lammers Ivonne , Lhiaubet‐Vallet Virginie , Consuelo Jiménez M. , Ariese Freek , Miranda Miguel A. , Gooijer Cees 
Published: June 2012

ABSTRACTThe interaction of the nonsteroidal anti‐inflammatory drug flurbiprofen (FBP) with human serum albumin (HSA) hardly influences the fluorescence of the protein's single tryptophan (Trp). Therefore, in addition to fluorescence, heavy atom‐induced room‐temperature phosphorescence is used to study the stereoselective binding of FBP enantiomers and their methyl esters to HSA. Maximal HSA phosphorescence intensities were obtained at a KI concentration of 0.2 M. The quenching of the Trp phosphorescence by FBP is mainly dynamic and based on Dexter energy transfer. The Stern–Volmer plots based on the phosphorescence lifetimes indicate that (R)‐FBP causes a stronger Trp quenching than (S)‐FBP. For the methyl esters of FBP, the opposite is observed: (S)‐(FBPMe) quenches more than (R)‐FBPMe. The Stern–Volmer plots of (R)‐FBP and (R)‐FBPMe are similar although their high‐affinity binding sites are different. The methylation of (S)‐FBP causes a large change in its effect on the HSA phosphorescence lifetime. Furthermore, the quenching constants of 3.0 × 107 M−1 s−1 of the R‐enantiomers and 2.5 × 107 M−1 s−1 for the S‐enantiomers are not influenced by the methylation and indicate a stereoselectivity in the accessibility of the HSA Trp to these drugs. Chirality 24:840–846, 2012. © 2012 Wiley Periodicals, Inc.
Multiple threads and parallel challenges for large simulations to accelerate a general Navier–Stokes CFD code on massively parallel systems
Authors: Fournier Yvan , Bonelle Jerome , Vezolle Pascal , Heyman Jerry , D'Amora Bruce , Magerlein Karen , Magerlein John , Braudaway Gordon , Moulinec Charles , Sunderland Andrew 
Published: June 2012

SUMMARYComputational fluid dynamics is an increasingly important application domain for computational scientists. In this paper, we propose and analyze optimizations necessary to run CFD simulations consisting of multibillion‐cell mesh models on large processor systems. Our investigation leverages the general industrial Navier–Stokes CFD application, Code_Saturne, developed by Electricité de France for incompressible and nearly compressible flows. In this paper, we outline the main bottlenecks and challenges for massively parallel systems and emerging processor features such as many‐core, transactional memory, and thread level speculation. We also present an approach based on an octree search algorithm to facilitate the joining of mesh parts and to build complex larger unstructured meshes of several billion grid cells. We describe two parallel strategies of an algebraic multigrid solver and we detail how to introduce new levels of parallelism based on compiler directives with OpenMP, transactional memory and thread level speculation, for finite volume cell‐centered formulation and face‐based loops. A renumbering scheme for mesh faces is proposed to enhance thread‐level parallelism. Copyright © 2012 John Wiley & Sons, Ltd.
Quantized Electron‐Transfer Pathways at Nanoparticle–Redox Centre Hybrids
Authors: Cabo‐Fernández Laura , Bradley Dan F. , Romani Simon , Higgins Simon J. , Schiffrin David J. 
Published: June 2012

AbstractHexanethiolate gold monolayer‐protected clusters (C6‐MPCs) with an average core diameter of 1.8 nm and a capacitance of 0.6 aF are synthesised by a two‐phase method. These clusters are functionalised with (6‐ferrocenyl)‐1‐hexanethiol by a place exchange reaction at different molar ratios. The average number of ferrocene centres per cluster determined by 1H NMR is ten, seven and four. Differential pulse voltammetry and cyclic voltammetry measurements for cluster solutions in 0.1 M TBAPF6/Tol:AN (2:1) clearly show the response of the Fc+/Fc redox couple and of quantized double layer (QDL) charging events of the gold core. A transition from single to multiple electron‐transfer response for the redox couple is observed as the number of ferrocene units per cluster is increased. The distances between the redox moieties are estimated considering a homogeneous distribution of the redox sites on the nanoparticle ligand shell. In all the cases, the inter‐ferrocene average separation is too large to observe self‐exchange reactions and the most likely electron‐transfer pathway is by fast rotational diffusion. The oxidation of the ferrocene groups results in an electrostatic switching‐off of electron transfers between the electrode and the nanoparticle core.
Water‐in‐Oil Micro‐Emulsion Enhances the Secondary Structure of a Protein by Confinement
Authors: Shipovskov Stepan , Oliveira Cristiano L. P. , Hoffmann Søren Vrønning , Schauser Leif , Sutherland Duncan S. , Besenbacher Flemming , Pedersen Jan Skov 
Published: June 2012

AbstractA scheme is presented in which an organic solvent environment in combination with surfactants is used to confine a natively unfolded protein inside an inverse microemulsion droplet. This type of confinement allows a study that provides unique insight into the dynamic structure of an unfolded, flexible protein which is still solvated and thus under near‐physiological conditions. In a model system, the protein osteopontin (OPN) is used. It is a highly phosphorylated glycoprotein that is expressed in a wide range of cells and tissues for which limited structural analysis exists due to the high degree of flexibility and large number of post‐translational modifications. OPN is implicated in tissue functions, such as inflammation and mineralisation. It also has a key function in tumour metastasis and progression. Circular dichroism measurements show that confinement enhances the secondary structural features of the protein. Small‐angle X‐ray scattering and dynamic light scattering show that OPN changes from being a flexible protein in aqueous solution to adopting a less flexible and more compact structure inside the microemulsion droplets. This novel approach for confining proteins while they are still hydrated may aid in studying the structure of a wide range of natively unfolded proteins.
Three‐dimensional unsteady thermocapillary flow under rotating magnetic field
Authors: Yao Liping , Zeng Zhong , Zhang Yi , Qiu Zhouhua , Mizuseki Hiroshi , Kawazoe Yoshiyuki 
Published: June 2012

AbstractUnder a rotating magnetic filed (RMF), the instability of thermocapillary flow and its evolution with increasing Marangoni number (Ma) for semiconductor melt (Pr = 0.01) in a floating liquid bridge model (As = 1) are investigated numerically. Under 5 mT RMF, the thermocapillary flow is steady and axisymmetric with Ma < Mac, and the critical Marangoni number Mac for convection instability is 29.5, which is obtained by the direct numerical simulation. When the Ma is a little bit beyond the Mac, the thermocapillary flow loses stability to become a three‐dimensional rotating oscillatory convection, and a periodic oscillation is confirmed by the fast Fourier transform analysis, the oscillatory main frequency decays with increasing Ma. Under 1 mT–6 mT RMF, the Mac increases roughly with the magnetic strength except the Mac at 4 mT, where the corresponding change of flow mode after the instability is observed. The oscillatory convection occurs with a smaller Ma in the RMF than that without magnetic field. In addition, no instability toward a three‐dimensional steady convection, which is the state of thermocapillary flow without magnetic field after the first instability, is observed under the RMF.
Analysis and modeling of task scheduling in wireless sensor network based on divisible load theory
Authors: Dai Liang , Shen Zhong , Chen Ting , Chang Yilin 
Published: June 2012

SUMMARYIn this paper, we propose a novel task scheduling algorithm (Divisible Task scheduling Algorithm for Wireless sensor networks (DTAW)) based on divisible load theory in heterogeneous wireless sensor networks to complete the tasks within the shortest possible time and reduce the sensors' energy‐consuming. In DTAW, the tasks are distributed to the wireless sensor network by the (SINK) on the basis of the processing and communication capacity of each sensor. After receiving the subtasks, the intracluster sensors carry out its tasks simultaneously and send the results to cluster head sequentially. By removing communication interference between each sensor, reduced task completion time and improved network resource utilization are achieved. Each cluster head simultaneously finishes sending fused data to the SINK after fusing the data obtained from intracluster sensors. In this way, the overlap between the task performing and communication phase would be much better. Simulation results are presented to demonstrate the impacts of different network parameters on the makespan and energy consumption. The results show that the algorithm enables to reasonably distribute tasks to each sensor and then effectively reduces the time‐consuming and energy‐consuming. Copyright © 2012 John Wiley & Sons, Ltd.
Complex agro‐ecosystems for food security in a changing climate
Authors: Khumairoh Uma , Groot Jeroen C.J. , Lantinga Egbert A. 
Published: June 2012

AbstractAttempts to increase food crop yields by intensifying agricultural systems using high inputs of nonrenewable resources and chemicals frequently lead to de‐gradation of natural resources, whereas most technological innovations are not accessible for smallholders that represent the majority of farmers world wide. Alternatively, cocultures consisting of assemblages of plant and animal species can support ecological processes of nutrient cycling and pest control, which may lead to increasing yields and declining susceptibility to extreme weather conditions with increasing complexity of the systems. Here we show that enhancing the complexity of a rice production system by adding combinations of compost, azolla, ducks, and fish resulted in strongly increased grain yields and revenues in a season with extremely adverse weather conditions on East Java, Indonesia. We found that azolla, duck, and fish increased plant nutrient content, tillering and leaf area expansion, and strongly reduced the density of six different pests. In the most complex system comprising all components the highest grain yield was obtained. The net revenues of this system from sales of rice grain, fish, and ducks, after correction for extra costs, were 114% higher than rice cultivation with only compost as fertilizer. These results provide more insight in the agro‐ecological processes and demonstrate how complex agricultural systems can contribute to food security in a changing climate. If smallholders can be trained to manage these systems and are supported for initial investments by credits, their livelihoods can be improved while producing in an ecologically benign way.
Removing woody vegetation has little effect on conduit flow recharge
Authors: Bazan Roberto A. , Wilcox Bradford P. , Munster Clyde , Gary Marcus 
Published: June 2012

ABSTRACTIn drylands across the globe, grasslands and savannas have succumbed to encroachment by woody plants. There is a concern that, in some cases, these changes may lead to lower groundwater recharge and streamflow. In karst landscapes, the effect of woody plants on recharge is difficult to determine because of the shallow and rocky soils. In our study, we estimated the amount of water entering a shallow cave (3–5 m deep) as a surrogate measurement for groundwater recharge, to evaluate whether the removal of Ashe juniper (Juniperus ashei) above the cave would affect recharge. Three sets of large‐scale rainfall simulations were conducted in 2005, before removal of the overstory juniper; seven were conducted in 2008, soon after the juniper were removed; and two were conducted in 2009, one year after juniper removal. We found that recharge occurred mainly via conduits or macropores and, as such, was extremely dynamic and responsive to rainfall. The amount of recharge ranged from 3% to 17% of the water applied, the higher percentages being measured when antecedent soil conditions were wet. At least in this case of recharge taking place via conduit flow, removal of the juniper had little if any effect. Copyright © 2012 John Wiley & Sons, Ltd.
Cyano‐Bridged 4f‐3d Assemblies with Achiral Helical Chains: Syntheses, Structures, and Magnetic Properties
Authors: Yu Deng‐Yong , Li Li , Zhou Hu , Yuan Ai‐Hua , Li Yi‐Zhi 
Published: June 2012

AbstractThe self‐assembly reaction of [Cr(CN)6]3–, Ln3+, and a chelated phen ligand resulted in the first examples of cyano‐bridged 3d‐4f helical chains [Ln(phen)3(H2O)][Cr(CN)6]·3H2O [Ln = La (1), Ce (2), Pr (3) and Nd (4)], in which the lanthanide center was coordinated unusually by three molecules of a bidentate ligand. The magnetic properties of compounds 2–4 were also investigated.
Antibacterial Activity of Silver‐Loaded “Green Zeolites”
Authors: Saint‐Cricq Philippe , Kamimura Yoshihiro , Itabashi Keiji , Sugawara‐Narutaki Ayae , Shimojima Atsushi , Okubo Tatsuya 
Published: June 2012

Abstract“Green Zeolites” were prepared, without the use of organic structure‐directing agents (OSDAs), by the seed‐assisted method and were loaded with silver by a simple ion‐exchange procedure. The silver‐loaded zeolites were characterized by XRD, transmission electron microscopy and inductively coupled plasma atomic emission spectroscopy, which reveals that the ion‐exchange procedure does not affect the structure of the zeolites and the presence of silver cations inside the aluminosilicate matrix. Two types of zeolites presenting different pore arrangements were studied: the beta‐type with three‐dimensionally interconnected pores and the MTW‐type with one‐dimensionally interconnected pores. Their activity against E. coli was studied and compared with a commercial zeolite. The influence of the arrangement of the pore channels and the amount of silver loaded were studied. Comparison with the commercial product shows that a smaller amount of silver inside the zeolite is necessary to achieve a similar antibacterial performance within one hour.
Luminescence of ortho‐Metalated Iridium Complexes Encapsulated in Zeolite Supercages by the Ship‐in‐a‐Bottle Method (Eur. J. Inorg. Chem. 19/2012)
Authors: Xu Chen , Mochizuki Dai , Hashimoto Yuta , Honda Takehisa , Tsukahara Yasunori , Yamauchi Tomohisa , Wada Yuji 
Published: June 2012

AbstractThe cover picture shows the encapsulation of iridium(III) complexes in the supercages of faujasite‐type zeolites. Iridium–carbon σ‐bond formation in the zeolites is achieved by using a microwave‐assisted ship‐in‐a‐bottle synthesis. A successive reaction of IrIII cations in the zeolite with the two ligands leads to the coexistence of two individual types of complexes in the different supercages, and the emission colors emitted from the IrIII complexes in the zeolites can be tuned and range from blue to green. Details are discussed in the article by Y. Wada et al. on p. 3113 ff. magnified image