bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphologic Pattern of Late Gadolinium Enhancement in Takotsubo Cardiomyopathy Detected by Early Cardiovascular Magnetic Resonance
Authors: Avegliano Gustavo , Huguet Marina , Costabel Juan P. , Ronderos Ricardo , Bijnens Bart , Kuschnir Paola , Thierer Jorge , Tobón‐Gomez Carolina , Martinez Guillermo Oller , Frangi Alejandro 
Published: March 2011

AbstractBackground:Takotsubo cardiomyopathy (TTC) presents clinically as an acute coronary syndrome. It is characterized by transient left ventricular wall dyskinesis‐akinesis, without significant epicardial coronary lesions. Late gadolinium enhancement (LGE) sequences on cardiac magnetic resonance (CMR) allow to clarify the pathophysiology in patients with chest pain, elevated troponin, and normal epicardial coronary arteries; in patients with TTC, previous studies have shown absence of LGE.Hypothesis:Early CMR in Takotsubo patients could show a morphological pattern of LGE improving clinical diagnosis.Methods:Between January 2005 and January 2007, 8 consecutive patients with TTC criteria underwent CMR within the first 3 days of admission. Cine, T2‐weighted, and LGE images were acquired. Patient follow‐up included clinical exam and imaging techniques: echocardiogram on days 3, 7, 30, and 60, and CMR at 3 months.Results:Six patients had experienced a previous stressful situation. No significant lesions were found on coronary angiography, and wall motion improvement was noted at 15 (7–30) days. Median EFs at admission and recovery were 46.5% and 65%, respectively. Dyskinesis was midapical in 6 cases, apical in 1 case, and mid‐ventricular in 1 case. Late gadolinium enhancement showed mild hyperenhancement in areas of abnormal wall motion, whereas normal segments had no contrast enhancement. On follow‐up CMR, wall motion was normal without late enhancement.Conclusions:Early CMR in TTC demonstrates a special morphological pattern of late gadolinium uptake that might correspond to localized inflammation and edema in the affected area, suggesting diffuse microcirculation damage rather than epicardial vessel involvement. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.
Surface waves on steady perfect‐fluid flows with vorticity
Authors: Burton G. R. , Toland J. F. 
Published: March 2011

AbstractThis is a theory of two‐dimensional steady periodic surface waves on flows under gravity in which the given data are three quantities that are independent of time in the corresponding evolution problem: the volume of fluid per period, the circulation per period on the free stream line, and the rearrangement class (equivalently, the distribution function) of the vorticity field. A minimizer of the total energy per period among flows satisfying these three constraints is shown to be a weak solution of the surface wave problem for which the vorticity is a decreasing function of the stream function. This decreasing function can be thought of as an infinite‐dimensional Lagrange multiplier corresponding to the vorticity rearrangement class being specified in the minimization problem. (Note that functional dependence of vorticity on the stream function was not specified a priori but is part of the solution to the problem and ensures the flow is steady.) To illustrate the idea with a minimum of technical difficulties, the existence of nontrivial waves on the surface of a fluid flowing with a prescribed distribution of vorticity and confined beneath an elastic sheet is proved. The theory applies equally to irrotational flows and to flows with locally square‐integrable vorticity. © 2011 Wiley Periodicals, Inc.
An optimal family of exponentially accurate one‐bit Sigma‐Delta quantization schemes
Authors: Deift Percy , Krahmer Felix , Güntürk C. Sınan 
Published: March 2011

AbstractSigma‐delta modulation is a popular method for analog‐to‐digital conversion of bandlimited signals that employs coarse quantization coupled with oversampling. The standard mathematical model for the error analysis of the method measures the performance of a given scheme by the rate at which the associated reconstruction error decays as a function of the oversampling ratio λ. It was recently shown that exponential accuracy of the form O(2−rλ) can be achieved by appropriate one‐bit sigma‐delta modulation schemes. By general information‐entropy arguments, r must be less than 1. The current best‐known value for r is approximately 0:088. The schemes that were designed to achieve this accuracy employ the “greedy” quantization rule coupled with feedback filters that fall into a class we call “minimally supported.” In this paper, we study the discrete minimization problem that corresponds to optimizing the error decay rate for this class of feedback filters. We solve a relaxed version of this problem exactly and provide explicit asymptotics of the solutions. From these relaxed solutions, we find asymptotically optimal solutions of the original problem, which improve the best‐known exponential error decay rate to r ≈ 0.102. Our method draws from the theory of orthogonal polynomials; in particular, it relates the optimal filters to the zero sets of Chebyshev polynomials of the second kind. © 2011 Wiley Periodicals, Inc.
Saccharification of Natural Lignocellulose Biomass and Polysaccharides by Highly Negatively Charged Heteropolyacids in Concentrated Aqueous Solution
Authors: Ogasawara Yoshiyuki , Itagaki Shintaro , Yamaguchi Kazuya , Mizuno Noritaka 
Published: March 2011

AbstractHighly negatively charged heteropolyacids (HPAs), in particular H5BW12O40, efficiently promoted saccharification of crystalline cellulose into water‐soluble saccharides in concentrated aqueous solutions (e.g., 82 % total yield and 77 % glucose yield, based on cellulose with a 0.7 M H5BW12O40 solution); the performance was much better than those of previously reported systems with commonly utilized mineral acids (e.g., H2SO4 and HCl) and HPAs (e.g., H3PW12O40 and H4SiW12O40). Besides crystalline cellulose, the present system was applicable to the selective transformation of cellobiose, starch, and xylan to the corresponding monosaccharides such as glucose and xylose. In addition, one‐pot synthesis of levulinic acid and sorbitol directly from cellulose was realized by using concentrated HPA solutions. The present system, concentrated aqueous solutions of highly negatively charged HPAs, was further applicable to saccharification of natural (non‐purified) lignocellulose biomass, such as “rice plant straw”, “oil palm empty fruit bunch (palm EFB) fiber”, and “Japanese cedar sawdust”, giving a mixture of the corresponding water‐soluble saccharides, such as glucose (main product), galactose, mannose, xylose, arabinose, and cellobiose, in high yields (≥77 % total yields of saccharides based on holocellulose). Separation of the saccharides and H5BW12O40 was easy, and the retrieved H5BW12O40 could repeatedly be used without appreciable loss of the high performance.
Enabling live video streaming services realization in telecommunication networks using P2P technology
Authors: Efthymiopoulos Nikolaos , Tompros Spyridon L. , Christakidis Athanasios , Koutsopoulos Konstantinos , Denazis Spyros 
Published: March 2011

SUMMARYPeer‐to‐peer (P2P) systems enjoy wide adoption from internet users. Success of P2P architecture is due to its ability to scale and organize dynamically the traffic according to the user resources and requests. However, P2P adoption is constrained in non‐real time applications, like content distribution and file sharing. The major reason behind this fact is the inability of P2P to deliver content within user‐desired bit rates by making optimal use of network resources. In this paper we focus on the solution and implementation of technical problems toward a complete system implementation that delivers live multimedia streaming through P2P architecture by the use of IMS. The content indexing and discovery, the scalable management and the distributed optimization of the graph that connects participating peers, the distributed scheduling mechanisms for data exchange, a scalable monitoring architecture and a bandwidth control mechanism constitute the major components toward a complete scalable multimedia streaming system offering streaming stability and high performance. Copyright © 2011 John Wiley & Sons, Ltd.
Evaluating and Regulating the Impacts of Lobbying in theEU? The Case Study of Green Industries
Authors: Svendsen Gert Tinggaard 
Published: March 2011

ABSTRACTHow should we evaluate and regulate the impacts of lobbying in the European Union (EU)? The current lack of transparency around lobbying activities and the absence of formal regulation mean that a hidden lobbying problem may prevail. The tentative case study of green industries in the EU is illustrative. The wind turbine industry, for example, benefits from ambitious environmental target levels for greenhouse gas reductions that will increase the future market for renewable energy. In contrast, for example, no environmental target levels exist that increase the future market shares of organic farming. Rational choice theory suggests that lobbying and group size advantages can explain the observed difference in achieving environmental target levels. The EU may learn from the US legislation as a starting point for a best‐practice solution and future evaluation of impacts of lobbying in the EU. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment
Modification of Nanocrystalline TiO2 with Phosphonate‐ and Bis(phosphonate)‐Bearing Macrocyclic Complexes: Sorption and Stability Studies
Authors: Řehoř Ivan , Kubíček Vojtěch , Kotek Jan , Hermann Petr , Száková Jiřina , Lukeš Ivan 
Published: March 2011

AbstractThe first systematic study of chemical adsorption/desorption of phosphonic acid and geminal bis(phosphonic acid) on/from the surface of anatase nanoparticles is reported. Stable TiO2 colloidal nanodispersions were used in the study. The colloidal stability is preserved upon nanoparticle modification. A macrocyclic lanthanide(III) complex, attached through a phosphonic/bis(phosphonic) group to the TiO2 surface allowed precise quantification of sorption parameters by means of inductively coupled plasma atomic emission spectroscopy (ICP‐AES). Results show different behavior of phosphonate and bis(phosphonate) groups. For phosphonate, a monomolecular layer formation was observed, and the desorption rate depends on the sorption conditions. It is probably caused by different phosphonate binding modes on the surface. Excess amounts of phosphate in the washing media accelerates the desorption rate of the phosphonate. The bis(phosphonate) is adsorbed on the surface in large quantities forming multilayers that resist desorption even in the presence of phosphate ions and, thus, the bis(phosphonate) moiety is a suitable group for anchoring other molecules on the TiO2 particle surface.
Metal–Metal Bonding in Bis(alkylthio)hexacarbonyldicobalt Complexes: Open Structures vs. Butterfly and Tetrahedrane Structures
Authors: Sárosi Menyhárt B. , Silaghi‐Dumitrescu Ioan , King R. Bruce 
Published: March 2011

AbstractDensity functional calculations on the Co2(CO)6(SR)2 compounds (R = CH3, CF3) predict both open and butterfly structure types of similar energies. The open Co2(CO)6(μ‐SR)2 structures have non‐planar central Co2S2 units with two bridging RS groups and ca. 3.4 Å Co···Co distances indicating a lack of direct metal–metal bonding. The butterfly Co2(CO)5(μ‐SR)(μ‐CO)(SR) structures have direct Co–Co bonds of lengths ca. 2.5 Å forming the “body” of the butterfly, one terminal RS group, one bridging RS group, and one bridging CO group. The lowest energy Co2(CO)6(SCH3)2 structure is an open isomer. However, this open isomer lies only 0.4 kcal/mol below the corresponding butterfly isomer. For the corresponding fluorinated derivative Co2(CO)6(SCF3)2 a butterfly structure with a direct Co–Co bond and a bridging CO group lies at a slightly lower energy than the lowest energy open structures. The relative energy difference between open and butterfly Co2(CO)6(SCF3)2 structures is more than five times higher than for the Co2(CO)6(SCH3)2 structures. The electronegativity of the RS group in the Co2(CO)6(SR)2 structures has little effect on the geometric parameters but exerts a significant influence on the atomic charge distribution. The butterfly structures with a direct metal–metal bond are predicted to be nearly isoenergetic to open structures without a Co–Co bond. Unsuccessful attempts to optimize a previously proposed Co2(CO)6(μ‐η2:η2‐S2R2) structure with a central Co2S2 tetrahedrane unit with one Co–Co bond, one S–S bond, and four Co–S bonds are consistent with the previous reformulation of the originally claimed Co2S2 tetrahedranes Co2(CO)6[μ‐η2:η2‐S2(C6X5)2] (X = F, Cl) as the trinuclear derivatives Co3(μ3‐S)(C6F5)(CO)8.
Role of Siloxides in Transition Metal Chemistry and Homogeneous Catalysis
Authors: Krempner Clemens 
Published: March 2011

AbstractThe role of siloxide ligands in the chemistry and catalysis of transition metals is reviewed. The first part deals with recent aspects of low‐valent transition metal siloxide chemistry, while the second part describes some developments in the chemistry of transition metal siloxides in high oxidation states, in particular with regard to the stability of the M–OSi bond. The third part highlights applications of well‐defined late and early transition metal siloxides as “single site” catalysts in homogeneous catalysis. Special emphasis is placed on the steric and electronic influence of the siloxide ligand on the activity, selectivity, and stability of the catalytically active metal species.
DNA Photocleavage and Cytotoxic Properties of Ferrocene Conjugates (Eur. J. Inorg. Chem. 9/2011)
Authors: Maity Basudev , Chakravarthi Balabhadrapatruni V. S. K. , Roy Mithun , Karande Anjali A. , Chakravarty Akhil R. 
Published: March 2011

AbstractThe cover picture shows “bioorganometallics in PDT” in which a ferrocene‐conjugated imidazophenanthroline derivative exhibits significant photocytotoxic effects in human cervical cancer HeLa cells in visible light, while being less cytotoxic in the unexposed state. The compound is also an efficient DNA snapper in visible light. Details are discussed in the article by A. R. Chakravarty et al. on p. 1379 ff.
Homocoupling of Terminal Alkynes Catalysed by Ultrafine Copper Nanoparticles on Titania
Authors: Alonso Francisco , Melkonian Taki , Moglie Yanina , Yus Miguel 
Published: March 2011

AbstractCopper nanoparticles on titania effectively catalyse the oxidative homocoupling of terminal alkynes in the presence of piperidine as a base in tetrahydrofuran (THF) or under solvent‐free conditions. A wide range of diynes have been synthesised in high yields using low catalyst loading (1 mol‐% Cu). The copper catalyst (mainly as Cu2O) has been characterised by different means, is easy to prepare, can be reutilised several times, works either in air or under inert atmosphere and was shown to be superior to other commercially available copper sources.
Linking ecology with economy: Insights into polyhydroxyalkanoate‐producing microorganisms
Authors: Koller Martin , Gasser Ilona , Schmid Florian , Berg Gabriele 
Published: March 2011

AbstractPolyhydroxyalkanoates (PHA) constitute a group of microbial biopolyesters with important ecosystem functions and a high biotechnological potential. During the past decade, the rapid development of new molecular and microscopic techniques resulted in novel insights into the ecology of PHA‐producing bacteria in aquatic and terrestrial microenvironments. Ecosystems showing fluctuating availability of carbon or transient limitation of essential nutrients, e.g. the rhizosphere of plants or estuarine sediments, contain a broad number of various PHA producers. PHA‐producing microorganisms show a widespread phylogenetic diversity and are often characterized by a symbiotic or syntrophic life style. PHA are already produced commercially in large‐scale fermentation. However, they have to compete economically with petrol‐based polymers. Hence, the development of low‐cost production strategies on the basis of diverse renewable materials is a crucial challenge. Ecological knowledge is required for these developments, which links both parts of the review together. The article highlights how a better understanding of the ecology of PHA‐producing microorganisms can lead to a broader application of microbial biopolymers on the basis of sustainable production processes. These processes have to be evaluated by means of life cycle assessment and Cleaner Production studies prior to their industrial implementation.
Disordered Eating Prevention Programme in Schools: A 30‐Month Follow‐up
Authors: González Marcela , Penelo Eva , Gutiérrez Teresa , Raich Rosa M. 
Published: March 2011

AbstractObjectiveThe present study aims to evaluate the long‐term effects of a school‐based prevention programme administered to adolescents; the purpose of the said programme was to reduce disordered eating attitudes and sociocultural influences on the internalisation of the aesthetical body ideal.MethodsA total of 254 girls and 189 boys were assigned to a control (n = 201) or to two experimental conditions: media literacy programme (n = 143) and media literacy plus nutrition awareness programme (n = 99). Pretest, post‐test (1 month later) and 7‐month and 30‐month follow‐up measurements were taken using the Eating Attitudes Test (EAT‐40) and the questionnaire on influences of aesthetic body ideal‐26/cuestionario de influencias del modelo estético corporal (CIMEC‐26). Linear mixed‐model analyses were conducted with a 2 × 3 × 3 ANOVA (sex × group × phase), adjusted by the baseline level.ResultsThe participants from both prevention programmes scored lower than the participants in the control group at follow‐up assessments on EAT‐40 and CIMEC‐26 scores.DiscussionBoth media literacy‐based programmes can be effective interventions reducing long‐term self‐reported disordered eating attitudes and internalisation of the aesthetic body ideal in a universal mixed‐sex school‐going adolescent population. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
A Psychometric Exploration of an Italian Translation of the SCOFF Questionnaire
Authors: Pannocchia Linda , Di Fiorino Mario , Giannini Marco , Vanderlinden Johan 
Published: March 2011

AbstractThe SCOFF is a quick and simple screening tool for eating disorders (EDs), intended for use by those who are not specialists in the field. The purpose of the present study is to explore the psychometric properties of an Italian version of the instrument. An Italian translation of the SCOFF was administered, together with a part of the Italian version of the Eating Disorders Inventory‐3, to the following: (i) a sample of psychiatric patients diagnosed with ED according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition; (ii) a sample of female psychiatric controls with no ED symptoms; and (iii) a sample of female normal controls without EDs from the general population. Results suggest that the Italian version of the SCOFF provides a reliable and valid tool for screening EDs. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
Daily FX Volatility Forecasts: Can the GARCH(1,1) Model be Beaten using High‐Frequency Data?
Authors: Mcmillan David G. , Speight Alan E. H. 
Published: March 2011

ABSTRACTVolatility forecasting remains an active area of research with no current consensus as to the model that provides the most accurate forecasts, though Hansen and Lunde (2005) have argued that in the context of daily exchange rate returns nothing can beat a GARCH(1,1) model. This paper extends that line of research by utilizing intra‐day data and obtaining daily volatility forecasts from a range of models based upon the higher‐frequency data. The volatility forecasts are appraised using four different measures of ‘true’ volatility and further evaluated using regression tests of predictive power, forecast encompassing and forecast combination. Our results show that the daily GARCH(1,1) model is largely inferior to all other models, whereas the intra‐day unadjusted‐data GARCH(1,1) model generally provides superior forecasts compared to all other models. Hence, while it appears that a daily GARCH(1,1) model can be beaten in obtaining accurate daily volatility forecasts, an intra‐day GARCH(1,1) model cannot be. Copyright © 2011 John Wiley & Sons, Ltd.
Forecasting Aggregated Moving Average Processes with an Application to the Euro Area Real Interest Rate
Authors: Sbrana Giacomo 
Published: March 2011

ABSTRACTThis paper focuses on the contemporaneous aggregation of moving average processes. It is shown that aggregating across second (or first)‐order (integrated) moving average processes leads to a macro process whose parameters are exact functions of the parameters of its generation process. Similar results are obtained at single equation level when a vector moving average framework is considered. In addition, the out‐of‐sample forecasting properties of aggregate and disaggregate procedures to forecast the aggregate variable are provided. Moreover, it is shown that the condition of equality of aggregate and disaggregate predictors is not necessary for the equality of their mean squared errors. Finally, an application to the euro area real interest rate is presented and discussed. Copyright © 2011 John Wiley & Sons, Ltd.
Do Long‐Run Theory Restrictions Help in Forecasting?
Authors: Mahdi Barakchian S. 
Published: March 2011

ABSTRACTDo long‐run equilibrium relations suggested by economic theory help to improve the forecasting performance of a cointegrated vector error correction model (VECM)? In this paper we try to answer this question in the context of a two‐country model developed for the Canadian and US economies. We compare the forecasting performance of the exactly identified cointegrated VECMs to the performance of the over‐identified VECMs with the long‐run theory restrictions imposed. We allow for model uncertainty and conduct this comparison for every possible combination of the cointegration ranks of the Canadian and US models. We show that the over‐identified structural cointegrated models generally outperform the exactly identified models in forecasting Canadian macroeconomic variables. We also show that the pooled forecasts generated from the over‐identified models beat most of the individual exactly identified and over‐identified models as well as the VARs in levels and in differences. Copyright © 2011 John Wiley & Sons, Ltd.