bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zirconocene Alkoxides, Promising Precursors for MOCVD of Zirconium Dioxide Thin Films
Authors: Sartori Andrea , El Habra Naida , De Zorzi Chiara , Sitran Sergio , Casarin Maurizio , Cavinato Gianni , Sada Cinzia , Gerbasi Rosalba , Rossetto Gilberto 
Published: May 2012

AbstractSome new volatile bis‐cyclopentadienyl zirconium alkoxides of the type Cp2Zr(OR)(OtBu) (R = iPr, Et, Me) is synthesized by the reaction of the corresponding KOR with the intermediate Cp2ZrCl(OtBu). Moreover, an alternative and convenient synthesis of Cp2Zr(OtBu)2, based on the reaction of Cp2ZrCl2 with an excess of tert‐butanol and triethylamine, is reported. The obtained compounds are identified by chemical analyses, thermogravimetric measurements, infrared (IR), nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry (MS). Furthermore, a crystallographic study of Cp2ZrCl(OtBu) is also reported. Cp2Zr(OtBu)2 and Cp2Zr(OiPr)(OtBu) are then used for depositing zirconia thin films of high quality and purity on Si(100) and stainless steel AISI 316 substrates by metal‐organic (MO)CVD. The microstructure and composition of the deposits are investigated by X‐ray diffraction (XRD) and secondary ion mass spectrometry (SIMS), while their hardness and elastic recovery on the AISI 316 substrate are measured using load‐depth nano‐indentation tests. The outcomes are consistent with a significant increase in the Berkovich hardness of the coated samples compared to that of bulk AISI 316.
Production of Predominantly Anatase Thin Films on Various Grades of Steel and Other Metallic Substrates From TiCl4 and Ethyl Acetate by Atmospheric Pressure CVD
Authors: Cross Alison J. , Dunnill Charles W. , Parkin Ivan P. 
Published: May 2012

AbstractTiO2 thin films are deposited by atmospheric pressure (AP)CVD of TiCl4 and ethyl acetate on various substrates heated to 500 °C. The substrates investigated are four different grades of stainless steel (304, 304L, 316, and 316L), titanium metal, gold‐coated titanium metal, and gold‐coated stainless steel (316 grade). The TiO2 films are analyzed by Raman spectroscopy (RS) to determine the percentage of anatase present. Predominantly anatase films are produced on all the substrates, demonstrating the versatility of this method. Scanning electron microscopy (SEM) images reveal a marked difference in particle size between regions of high anatase content and lower anatase content, indicative of a difference in growth rate between anatase and rutile particles. Selected samples are shown to be photocatalytically active by degradation of resazurin dye by UV light. The rate of degradation is significantly faster than on the self‐cleaning Saint Gobain Bioclean™.
Enhancement of Photoelectrochemical Performance of AACVD‐produced TiO2 Electrodes by Microwave Irradiation while Preserving the Nanostructure
Authors: Tahir Asif Ali , Peiris T. A. Nirmal , Wijayantha K. G. Upul 
Published: May 2012

AbstractTiO2 electrodes are deposited on FTO‐glass substrates at 350 and 400 °C by aerosol‐assisted chemical vapour deposition (AACVD) and the deposited TiO2 electrodes are irradiated with microwave radiation (2.45 GHz) at various percentages (10, 25, 50, and 100%). X‐ray diffraction (XRD) pattern shows that the deposited electrodes have anatase phase TiO2 oriented in the (101) direction, and the crystallinity of these electrodes increases after microwave treatment. Field emission gun scanning electron microscopy (FEG‐SEM) surface topography analysis proves the preservation of the nanostructure after exposure to various percentages of microwave radiation. The photoelectrochemical (PEC) studies prove a threefold enhancement of photocurrent density of AACVD‐produced TiO2 electrodes after 100% microwave irradiation. This improved performance of PEC properties is attributed to improvements in the crystallinity and the particle‐necking properties. The results presented demonstrate that microwave processing is a promising alternative method to conventional sintering for TiO2 photoanodes.
Defining progressive stages in the commitment process leading to embryonic lens formation
Authors: Jin Hong , Fisher Marilyn , Grainger Robert M. 
Published: May 2012

AbstractThe commitment of regions of the embryo to form particular tissues or organs is a central concept in development, but the mechanisms controlling this process remain elusive. The well‐studied model of lens induction is ideal for dissecting key phases of the commitment process. We find in Xenopus tropicalis, at the time of specification of the lens, i.e., when presumptive lens ectoderm (PLE) can be isolated, cultured, and will differentiate into a lens that the PLE is not yet irreversibly committed, or determined, to form a lens. When transplanted into the posterior of a host embryo lens development is prevented at this stage, while ∼ 3 h later, using the same assay, determination is complete. Interestingly, we find that specified lens ectoderm, when cultured, acquires the ability to become determined without further tissue interactions. Furthermore, we show that specified PLE has a different gene expression pattern than determined PLE, and that determined PLE can maintain expression of essential regulatory genes (e.g., foxe3, mafB) in an ectopic environment, while specified PLE cannot. These observations set the stage for a detailed mechanistic study of the genes and signals controlling tissue commitment. genesis 50:728–740, 2012. © 2012 Wiley Periodicals, Inc.
Selecting Policy Instruments for Better Environmental Regulation: a Critique and Future Research Agenda
Authors: Taylor Christopher , Pollard Simon , Rocks Sophie , Angus Andy 
Published: May 2012

ABSTRACTThere is a lack of evidence on regulatory effectiveness available to support policy makers with the selection of appropriate instruments to deliver better environmental regulation. We identify the types of evidence required to enable regulatory reform, characterize evidence gaps, and explore how these may be filled through future research. A typology of regulatory instruments is presented, and evidence of what has worked when and why is examined, drawing on international experience and recent cases from the United Kingdom (UK). Evidence of the capabilities of good environmental regulators for regulatory effectiveness is lacking, and it is proposed that ethnographic research that captures the nuances of regulatory practice will prove necessary to address this. This paper is of value to policy makers and regulators around the world considering the selection and deployment of the full range of environmental regulatory instruments to respond to environmental risks and in support of economic growth. It can inform the selection of suitable approaches and the design of institutions capable of delivering them. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.
Template‐Induced Structural Isomerism of Pyridine‐2,3‐dicarboxylate and PbII with Similar High Stability and Different Fluorescent Properties
Authors: Jia Yanyuan , Li Huijun , Guo Qianqian , Zhao Bei , Zhao Ying , Hou Hongwei , Fan Yaoting 
Published: May 2012

AbstractTwo template‐induced supramolecular isomers [Pb(2,3‐pyde)]n (1 and 2; 2,3‐pyde = pyridine‐2,3‐dicarboxylate) have been synthesized under hydrothermal conditions. Complex 1 displays a 2D network with a point symbol of (42·64)2, whereas complex 2 exhibits a 3D framework with a point symbol of (46·64)2. The study of the stability of the isomers demonstrates that they have high thermal stability and excellent chemical resistance to boiling water and common organic solvents. Interestingly, the two polymers evidently possess different fluorescent properties although they have the same chemical component.
An efficient and expeditious synthesis of phytostanyl esters in a solvent‐free system
Authors: Zhou Yang , Jia Chengsheng , Li Rui , Zhang Xiaoming , He Wensen , Li Jingjing , Feng Biao , Xia Qiuyu 
Published: May 2012

AbstractEsterification of natural phytostanols with various fatty acids by using Lewis acid‐surfactant combined catalyst was investigated. For synthesis of phytostanol esters of saturated fatty acids, cuprum dodecyl sulfate [Cu(DS)2] was the most desirable catalyst due to its high selectivity, reusability, activity, and less corrosivity, whereas stanol selectivity with other catalysts, such as ZnCl2 and tungstophosphoric acid. The substrate molar ratio of 1.2:1 (lauric acid/phytostanols) was the optimal. For synthesis of phytostanol esters of unsaturated fatty acids, cerium dodecyl sulfate [Ce(DS)3] was better than [Cu(DS)2] which was based on the oxidation of the unsaturated fatty acids during the reaction. The chemical structure of the sitostanyl stearate, sitostanyl oleate, and sitostanyl linoleate were confirmed by FTIR, MS, and NMR, respectively. As a result, the [Cu(DS)2] and [Ce(DS)3] were screened to synthesize phytostanyl esters of fatty acids for commercial production.Practical applications: Phytostanols are important for human health and nutrition. Unfortunately, due to the poor solubility of free stanols (unesterified) in fats and oils, there is a demand for a good way to improve the solubility or bioavailability of phytostanols, such as esterification of phytostanols with fatty acids. This study aims at finding an efficient and expeditious synthesis of phytostanyl esters. At the same time, environmental impact and the oxidation of the unsaturated fatty acids during the reaction should be considered.
Functionalized Phosphanyl‐Phosphonic Acids as Unusual Complexing Units as Analogues of Fosmidomycin
Authors: Montel Sonia , Midrier Camille , Volle Jean‐Noël , Braun Ralf , Haaf Klaus , Willms Lothar , Pirat Jean‐Luc , Virieux David 
Published: May 2012

AbstractFosmidomycin (1a) and FR‐90098 are potent inhibitors of 1‐deoxy‐D‐xylulose‐5‐phosphate reductoisomerase (DXR), the second enzyme of the non‐mevalonate (MEP) pathway responsible for the biosynthesis of isoprenoids. This paper describes the synthesis of four types of targets bearing a phosphanyl‐phosphonic acid motif as the common core for the inhibition of DXR. In these structures, the hydroxamic acid was replaced by various chelators based on a phosphinic acid linked to different functional groups capable of forming five‐ or six‐membered chelating rings.
Convenient Direct Syntheses of Selectively para‐Substituted Di‐, Tri‐ and Tetra‐Formylated Thiacalix[4]arenes
Authors: Yang Weiping , Wang Wei , Guo Rong , Gong Linbo , Gong Shuling 
Published: May 2012

AbstractAn efficient direct method for di‐, tri‐ and tetraformylation of thiacalix[4]arenes substituted on the para positions is described. Di‐ and triformylated thiacalix[4]arenes were obtained by formylation of partially propyl‐ or benzoyl‐substituted thiacalix[4]arenes. Complete para‐formylation was successfully achieved by formylation and dealkylation of tetraisopropoxythiacalix[4]arene conformers in one step. This experimental procedure is a simpler synthesis for completely formylated thiacalix[4]arene than the indirect method reported previously from brominated thiacalix[4]arene.
Modular Solid‐Phase Synthesis of Teroxazoles as a Class of α‐Helix Mimetics
Authors: Pinto Gomes Cristiano , Metz Alexander , Bats Jan W. , Gohlke Holger , Göbel Michael W. 
Published: May 2012

Abstractα‐Helices are ubiquitous structural elements of proteins and are important in molecular recognition. Small molecules mimicking α‐helices have proven to be valuable biophysical probes or modulators of protein‐protein interactions. Here, we present modeling studies and the modular solid‐phase synthesis of teroxazole derivatives as a new class of α‐helix mimetics. The synthesis is compatible with a variety of functional groups and should thus be generally applicable for generating diversely substituted oligo‐oxazole scaffolds. The teroxazole scaffold is predicted to be polar and to project peptidomimetic side chains at positions i, i+3, and i+6 of an α‐helix, which complements projection patterns of existing helix mimetics. The scaffold retains sufficient conformational flexibility to conform to induced‐fit models of protein‐protein interaction inhibition.
A method for semi‐automated objective quantification of linear bedforms from multi‐scale digital elevation models
Authors: Cazenave Pierre W. , Dix Justin K. , Lambkin David O. , McNeill Lisa C. 
Published: May 2012

ABSTRACTThe increasing availability of large, detailed digital representations of the Earth's surface demands the application of objective and quantitative analyses. Given recent advances in the understanding of the mechanisms of formation of linear bedform features from a range of environments, objective measurement of their wavelength, orientation, crest and trough positions, height and asymmetry is highly desirable. These parameters are also of use when determining observation‐based parameters for use in many applications such as numerical modelling, surface classification and sediment transport pathway analysis. Here, we (i) adapt and extend extant techniques to provide a suite of semi‐automatic tools which calculate crest orientation, wavelength, height, asymmetry direction and asymmetry ratios of bedforms, and then (ii) undertake sensitivity tests on synthetic data, increasingly complex seabeds and a very large‐scale (39 000 km2) aeolian dune system. The automated results are compared with traditional, manually derived, measurements at each stage. This new approach successfully analyses different types of topographic data (from aeolian and marine environments) from a range of sources, with tens of millions of data points being processed in a semi‐automated and objective manner within minutes rather than hours or days. The results from these analyses show there is significant variability in all measurable parameters in what might otherwise be considered uniform bedform fields. For example, the dunes of the Rub' al Khali on the Arabian peninsula are shown to exhibit deviations in dimensions from global trends. Morphological and dune asymmetry analysis of the Rub' al Khali suggests parts of the sand sea may be adjusting to a changed wind regime from that during their formation 100 to 10 ka BP. Copyright © 2012 John Wiley & Sons, Ltd.
NATURAL EXPERIMENT EVIDENCE ON THE EFFECT OF MIGRATION ON BLOOD PRESSURE AND HYPERTENSION
Authors: Gibson John , Stillman Steven , McKenzie David , Rohorua Halahingano 
Published: May 2012

ABSTRACTOver 200 million people worldwide live outside their country of birth and typically experience large gains in material well‐being by moving to where wages are higher. But, the effect of this migration on other dimensions of well‐being such as health are less clear and existing evidence is ambiguous because of potential for self‐selection bias. In this paper, we use a natural experiment, comparing successful and unsuccessful applicants to a migration lottery to experimentally estimate the impact of migration on measured blood pressure and hypertension. Hypertension is a leading global health problem, as well as being an important health measure that responds quickly to migration. We use various econometric estimators to form bounds on the treatment effects because there appears to be selective non‐compliance in the natural experiment. Even with these bounds, the results suggest significant and persistent increases in blood pressure and hypertension, which are likely to have implications for future health budgets given recent increases in developing to developed country migration. Copyright © 2012 John Wiley & Sons, Ltd.
Multi‐Criteria Usability Evaluation of Electronic Devices in a Fuzzy Environment
Authors: Atalay Kumru Didem , Eraslan Ergün 
Published: May 2012

AbstractThe user‐oriented design is the most important competition issue in today's market. In recent years, user‐oriented design (i.e., usability) has become expected, particularly in electronic devices. Usability considers high user satisfaction in conjunction with user performance. Usability of electronic products is essential for high customer satisfaction as well as product life cycles in companies. Therefore, MP3 players were selected among the electronic products. Designing usable MP3 players is extremely important for users who have close interaction with them. In this study, MP3 players of different types and sizes were selected and their usability evaluated. The usability criteria used in the MP3 players' evaluation were divided into two major categories: performance and emotional expectations. The alternatives were ranked with fuzzy multi‐criteria decision‐making methods, namely, Fuzzy TOPSIS (FTOPSIS), Fuzzy Analytic Hierarchy Process (FAHP), and Fuzzy Axiomatic Design Theory (FADT), and the results were compared. Although the same decision matrices and data obtained from semantic differential experiment were used for all fuzzy multi‐criteria decision‐making methods, it is shown that different rankings were obtained. © 2012 Wiley Periodicals, Inc.
Structural informatics, modeling, and design with an open‐source Molecular Software Library (MSL)
Authors: Kulp Daniel W. , Subramaniam Sabareesh , Donald Jason E. , Hannigan Brett T. , Mueller Benjamin K. , Grigoryan Gevorg , Senes Alessandro 
Published: May 2012

AbstractWe present the Molecular Software Library (MSL), a C++ library for molecular modeling. MSL is a set of tools that supports a large variety of algorithms for the design, modeling, and analysis of macromolecules. Among the main features supported by the library are methods for applying geometric transformations and alignments, the implementation of a rich set of energy functions, side chain optimization, backbone manipulation, calculation of solvent accessible surface area, and other tools. MSL has a number of unique features, such as the ability of storing alternative atomic coordinates (for modeling) and multiple amino acid identities at the same backbone position (for design). It has a straightforward mechanism for extending its energy functions and can work with any type of molecules. Although the code base is large, MSL was created with ease of developing in mind. It allows the rapid implementation of simple tasks while fully supporting the creation of complex applications. Some of the potentialities of the software are demonstrated here with examples that show how to program complex and essential modeling tasks with few lines of code. MSL is an ongoing and evolving project, with new features and improvements being introduced regularly, but it is mature and suitable for production and has been used in numerous protein modeling and design projects. MSL is open‐source software, freely downloadable at http://msl‐libraries.org. We propose it as a common platform for the development of new molecular algorithms and to promote the distribution, sharing, and reutilization of computational methods. © 2012 Wiley Periodicals, Inc.
Contrast‐enhanced multidetector‐row computed tomography vs. Time‐resolved magnetic resonance angiography vs. contrast‐enhanced perfusion MRI: Assessment of treatment response by patients with inoperable chronic thromboembolic pulmonary hypertension
Authors: Ohno Yoshiharu , Koyama Hisanobu , Yoshikawa Takeshi , Nishio Mizuho , Matsumoto Sumiaki , Matsumoto Keiko , Aoyama Nobukazu , Nogami Munenobu , Murase Kenya , Sugimura Kazuro 
Published: May 2012

AbstractPurpose:To compare therapeutic effect assessment capability of multidetector‐row computed tomography (MDCT), magnetic resonance angiography (MRA), and dynamic perfusion MRI for chronic thromboembolic pulmonary hypertension (CTEPH) patients.Materials and Methods:Twenty‐four consecutive CTEPH patients treated with conventional therapy underwent pre‐ and posttherapeutic MDCT, MRA, dynamic perfusion MRI, 6‐minute walk distance (6‐MWD), cardiac ultrasound (US), and right heart catheterization. According to therapeutic results, all patients were divided into response (n = 13) and nonresponse (n = 11) groups. CTEPH indexes for MDCT (CTEPHCT) and MRA (CTEPHMRA) were calculated on the basis of embolic burden. Pulmonary perfusion parameter maps were generated from all perfusion MR data, followed by determination of improvements in mean perfusion parameter at regions of interest (ROIs) for each patient. Receiver operating characteristic (ROC)‐based positive tests were performed to determine the feasible threshold values for distinguishing two groups. Finally, diagnostic capabilities were compared by means of McNemar's test.Results:When feasible threshold values adapted, specificity (90.9 〈10/11〉%, P < 0.05) and accuracy (95.8 〈23/24〉%, P < 0.05) for improvement in pulmonary blood flow were significantly higher than those for CTEPHCTA (specificity: 36.4 〈4/11〉%, accuracy: 70.8 〈17/24〉%).Conclusion:Dynamic perfusion MRI has better capability for assessment of therapeutic effect on CTEPH patients than does MDCT. J. Magn. Reson. Imaging 2012;36:612–623. © 2012 Wiley Periodicals, Inc.
Ferric ion could facilitate osteoclast differentiation and bone resorption through the production of reactive oxygen species
Authors: Jia Peng , Xu You Jia , Zhang Zeng Li , Li Kai , Li Bingyan , Zhang Wen , Yang Huilin 
Published: May 2012

AbstractIron overload is widely regarded as a risk factor for osteoporosis. It has been demonstrated that iron can inhibit osteoblast differentiation. However, the effects of iron on osteoclast differentiation and bone resorption remain controversial. In this study, we found that ferric ion promoted Receptor Activator of Nuclear Factor κ B Ligand (RANKL)‐induced osteoclast (OC) formation in both RAW264.7 cells and bone marrow‐derived macrophages (BMMs), and this effect was accompanied by elevated levels of reactive oxygen species (ROS) and oxidative stress. Moreover, this effect was attenuated by the administration of antioxidant N‐acetyl‐L‐cysteine (NAC). Therefore, we conclude that ferric ion can promote osteoclast differentiation and bone resorption through the production of ROS. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1843–1852, 2012
INTRODUCED EUCALYPTUS UROPHYLLA PLANTATIONS CHANGE THE COMPOSITION OF THE SOIL MICROBIAL COMMUNITY IN SUBTROPICAL CHINA
Authors: Wu J. P. , Liu Z. F. , Sun Y. X. , Zhou L. X. , Lin Y. B. , Fu S. L. 
Published: May 2012

ABSTRACTFast‐growing tree species are widely used as pioneers for reforestation. These plantations strongly affect the ecosystem productivity and nutrient cycling, whereas their effect on the soil microbial community is still unclear. In a reforestation chronosequence in subtropical China consisting of Eucalyptus plantation with ages of 1, 2, 4 or 5 years, we examined the response of the soil microbial community and its function. The results showed that soil bulk density and dissolved organic carbon decreased significantly along the chronosequence. Soil pH was highest in the 5‐year‐old plantation. The amount of bacterial phospholipid fatty acids (PLFAs) and arbuscular mycorrhizal fungal PLFAs increased, but the ratio of fungal‐to‐bacterial PLFAs decreased with increasing forest age. The composition of the soil microbial community obviously changed after 5 years' development. Redundancy analysis showed that dissolved organic carbon was the major factor associated with the changes of soil microbial community composition. The short‐rotation Eucalyptus plantation could affect the composition of soil microbial communities through changing soil available carbon when planted in subtropical region at the early developmental stage. We suggest that soil microbial community composition should be taken into consideration in the large‐scale reforestation activities. Copyright © 2012 John Wiley & Sons, Ltd.