Exchange

Distribution by Scientific Domains
Distribution within Chemistry

Kinds of Exchange

  • Athen stock exchange
  • acid exchange
  • amino acid exchange
  • anion exchange
  • australian stock exchange
  • carbon exchange
  • cation exchange
  • chemical exchange
  • chicago mercantile exchange
  • chromatid exchange
  • co2 exchange
  • conformational exchange
  • cultural exchange
  • d exchange
  • deuterium exchange
  • double exchange
  • ecosystem co2 exchange
  • ecosystem exchange
  • energy exchange
  • fast exchange
  • ferromagnetic exchange
  • financial future exchange
  • fluid exchange
  • foreign exchange
  • future exchange
  • gas exchange
  • gene exchange
  • genetic exchange
  • gift exchange
  • h exchange
  • h+ exchange
  • halogen exchange
  • heat exchange
  • hydrogen exchange
  • information exchange
  • international financial future exchange
  • ion exchange
  • isotope exchange
  • isotopic exchange
  • knowledge exchange
  • leader-member exchange
  • leaf gas exchange
  • ligand exchange
  • lithium exchange
  • little exchange
  • london international financial future exchange
  • london stock exchange
  • magnetic exchange
  • mass exchange
  • member exchange
  • mercantile exchange
  • momentum exchange
  • mutual exchange
  • na+/ca2+ exchange
  • na+/h+ exchange
  • net co2 exchange
  • net ecosystem co2 exchange
  • net ecosystem exchange
  • new york stock exchange
  • nucleotide exchange
  • option exchange
  • oxygen exchange
  • plasma exchange
  • rapid exchange
  • reciprocal exchange
  • sister chromatid exchange
  • social exchange
  • stock exchange
  • strand exchange
  • strong cation exchange
  • sydney future exchange
  • taiwan stock exchange
  • therapeutic plasma exchange
  • toronto stock exchange
  • water exchange
  • york stock exchange

  • Terms modified by Exchange

  • exchange activity
  • exchange bias
  • exchange capacity
  • exchange characteristic
  • exchange chromatography
  • exchange commission
  • exchange coupling
  • exchange coupling constant
  • exchange current
  • exchange data
  • exchange device
  • exchange economy
  • exchange efficiency
  • exchange energy
  • exchange event
  • exchange experiment
  • exchange factor
  • exchange inhibitor
  • exchange integral
  • exchange interaction
  • exchange intervention
  • exchange kinetics
  • exchange listing
  • exchange market
  • exchange market intervention
  • exchange measurement
  • exchange mechanism
  • exchange membrane
  • exchange membrane fuel cell
  • exchange model
  • exchange network
  • exchange option
  • exchange parameter
  • exchange process
  • exchange program
  • exchange programme
  • exchange property
  • exchange protein
  • exchange protocol
  • exchange rate
  • exchange rate appreciation
  • exchange rate arrangement
  • exchange rate change
  • exchange rate data
  • exchange rate depreciation
  • exchange rate dynamics
  • exchange rate fluctuation
  • exchange rate movement
  • exchange rate policy
  • exchange rate regime
  • exchange rate risk
  • exchange rate series
  • exchange rate system
  • exchange rate uncertainty
  • exchange rate variability
  • exchange rate volatility
  • exchange ratio
  • exchange reaction
  • exchange relationship
  • exchange relationships
  • exchange reserve
  • exchange resin
  • exchange response
  • exchange risk
  • exchange site
  • exchange student
  • exchange system
  • exchange theory
  • exchange therapy
  • exchange transfusion
  • exchange value

  • Selected Abstracts


    TRADING IN FOREIGN EXCHANGE

    ECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 2 2001
    TIFFANY HUTCHESON
    First page of article [source]


    SYRINGE EXCHANGE IN THE UNITED STATES: DOING THE SIMPLE THINGS BETTER?

    ADDICTION, Issue 9 2009
    LISA MAHER
    No abstract is available for this article. [source]


    THE ROLE OF JOB EMBEDDEDNESS ON EMPLOYEE PERFORMANCE: THE INTERACTIVE EFFECTS WITH LEADER,MEMBER EXCHANGE AND ORGANIZATION-BASED SELF-ESTEEM

    PERSONNEL PSYCHOLOGY, Issue 4 2008
    TOMOKI SEKIGUCHI
    Although job embeddedness was originally conceptualized to explain job stability or "why people stay" in their organizations, this investigation examines the role of job embeddedness as a hypothesized moderator of relationships among leader,member exchange (LMX), organization-based self-esteem (OBSE), organizational citizenship behaviors (OCBs), and task performance. Findings from 2 studies involving 367 employees and 41 supervisors, 1 in a telecommunications company and another in a manufacturing setting, support hypotheses concerning job embeddedness as a moderator of the relationship between (a) LMX and task performance within a telecommunication sample and LMX and OCBs in a sample of manufacturing employees, and (b) OBSE and OCBs in a manufacturing sample. Further, a hypothesized 3-way interaction involving job embeddedness, LMX, and OBSE on task performance was found in a sample of manufacturing employees. The implications of these findings for studying and managing job embeddedness in relation to employee performance are discussed. [source]


    WORK VALUE CONGRUENCE AND INTRINSIC CAREER SUCCESS: THE COMPENSATORY ROLES OF LEADER-MEMBER EXCHANGE AND PERCEIVED ORGANIZATIONAL SUPPORT

    PERSONNEL PSYCHOLOGY, Issue 2 2004
    BERRIN ERDOGAN
    We hypothesized that leader-member exchange (LMX) and perceived organizational support (POS) would each interact with work value congruence in relation to intrinsic career success. In a sample of 520 teachers from 30 high schools in Turkey, we found that work value congruence was positively related to job and career satisfaction when POS was low but not related to job and career satisfaction when POS was high. Similarly, work value congruence was positively related to career satisfaction when LMX was low but not related when LMX was high. The results contribute to the POS, LMX, and person-organization fit literatures by demonstrating the compensatory nature of LMX and POS for low value congruence in its relation to job and career satisfaction. [source]


    SOCIAL EXCHANGE AND ORGANIZATIONAL COMMITMENT: DECISION-MAKING TRAINING FOR JOB CHOICE AS AN ALTERNATIVE TO THE REALISTIC JOB PREVIEW

    PERSONNEL PSYCHOLOGY, Issue 3 2002
    YOAV GANZACH
    This field experiment investigated the effects of exchange-inducing treatments on pre- and postentry commitment of military recruits. Behavioral (volunteering for combat service and turnover), intentional (willingness to commit to combat service), and attitudinal (commitment, satisfaction, perceived fairness, and perceived choice variety) outcomes are examined. Two exchange-inducing experimental groups, one receiving realistic job preview and another receiving decisionmaking training, were compared to 3 control groups. Results indicated that preentry commitment was significantly higher among participants in the exchange-inducing conditions. However, the effect of decisionmaking training lasted longer than the effect of realistic job preview. [source]


    INFORMATION EXCHANGE AND COMPETITION IN COMMUNICATIONS NETWORKS,

    THE JOURNAL OF INDUSTRIAL ECONOMICS, Issue 4 2008
    CARLO CAMBINI
    Interconnection; Access charges; Reception charges; Information exchange We develop a model of information exchange between calling parties. We characterize the equilibrium when two interconnected networks compete by charging both for outgoing and incoming calls. We show that networks have reduced incentives to use off-net price discrimination to induce a connectivity breakdown when calls originated and received are complements in the information exchange. This breakdown disappears if operators are allowed to negotiate reciprocal access charges. We also study the relationship between sending and receiving retail charges as a function of the level of access charges. We identify circumstances where private negotiations over access charges induce first-best retail prices. [source]


    FROM SUSA TO ANURADHAPURA: RECONSTRUCTING ASPECTS OF TRADE AND EXCHANGE IN BITUMEN-COATED CERAMIC VESSELS BETWEEN IRAN AND SRI LANKA FROM THE THIRD TO THE NINTH CENTURIES AD*

    ARCHAEOMETRY, Issue 3 2008
    B. STERN
    In contrast with artefactual studies of long-distance trade and exchange in South Asia during the Prehistoric and Early Historic periods (Ardika et al. 1993; Gogte 1997; Krishnan and Coningham 1997; Tomber 2000; Gupta et al. 2001; Ford et al. 2005), few scientifically orientated analyses have focused on artefacts from the region's Historic period. During excavations at the ancient city of Anuradhapura, Sri Lanka, a number of buff ware ceramics with a putative organic coating on the interior were recovered (Coningham 2006). Dated stylistically to between the third and ninth centuries ad, analysis of the coatings using gas chromatography,mass spectrometry (GC,MS) and stable isotope analysis (carbon and deuterium) confirmed that the coatings are bitumen,an organic product associated with petroleum deposits. There are no known bitumen sources in Sri Lanka, and biomarker distributions and isotopic signatures suggest that the majority of the samples appear to have come from a single bitumen source near Susa in Iran. The relationship between the bitumen coatings and the vessels is discussed, and it is suggested that the coatings were used to seal permeable ceramic containers to allow them to transport liquid commodities. This study enhances our knowledge of networks of trade and exchange between Sri Lanka and western Asia during Historic times. [source]


    The determination of high-affinity protein/inhibitor binding constants by electrospray ionization hydrogen/deuterium exchange mass spectrometry

    RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 16 2006
    Lee Frego
    Recently, a hydrogen/deuterium exchange method termed SUPREX (Stability of Unpurified Proteins from Rates of hydrogen/deuterium EXchange), capable of measuring protein/ligand binding constants, which utilizes matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), has been reported. Unlike more conventional approaches, SUPREX is inherently capable of measuring Kd values of tight binding ligands. Here we present a SUPREX-based method, incorporating automation and electrospray ionization (ESI)-MS, to measure Kd values for very potent inhibitors of the kinase PKC,. The use of ESI offers an alternative to MALDI, with the advantages of improved mass measurement precision for larger proteins, and amenability to automation. Kd values generated by this method are in good agreement with those generated by a molecular protein kinase assay. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Empowering Automated Trading in Multi-Agent Environments

    COMPUTATIONAL INTELLIGENCE, Issue 4 2004
    David W. Ash
    Trading in the financial markets often requires that information be available in real time to be effectively processed. Furthermore, complete information is not always available about the reliability of data, or its timeliness,nevertheless, a decision must still be made about whether to trade or not. We propose a mechanism whereby different data sources are monitored, using Semantic Web facilities, by different agents, which communicate among each other to determine the presence of good trading opportunities. When a trading opportunity presents itself, the human traders are notified to determine whether or not to execute the trade. The Semantic Web, Web Services, and URML technologies are used to enable this mechanism. The human traders are notified of the trade at the optimal time so as not to either waste their resources or lose a good trading opportunity. We also have designed a rudimentary prototype system for simulating the interaction between the intelligent agents and the human beings, and show some results through experiments on this simulation for trading of the Chicago Board Options Exchange (CBOE) options. [source]


    Auditor Quality and the Accuracy of Management Earnings Forecasts,

    CONTEMPORARY ACCOUNTING RESEARCH, Issue 4 2000
    PETER M. CLARKSON
    Abstract In this study, we appeal to insights and results from Davidson and Neu 1993 and McConomy 1998 to motivate empirical analyses designed to gain a better understanding of the relationship between auditor quality and forecast accuracy. We extend and refine Davidson and Neu's analysis of this relationship by introducing additional controls for business risk and by considering data from two distinct time periods: one in which the audit firm's responsibility respecting the earnings forecast was to provide review-level assurance, and one in which its responsibility was to provide audit-level assurance. Our sample data consist of Toronto Stock Exchange (TSE) initial public offerings (IPOs). The earnings forecast we consider is the one-year-ahead management earnings forecast included in the IPO offering prospectus. The results suggest that after the additional controls for business risk are introduced, the relationship between forecast accuracy and auditor quality for the review-level assurance period is no longer significant. The results also indicate that the shift in regimes alters the fundamental nature of the relationship. Using data from the audit-level assurance regime, we find a negative and significant relationship between forecast accuracy and auditor quality (i.e., we find Big 6 auditors to be associated with smaller absolute forecast errors than non-Big 6 auditors), and further, that the difference in the relationship between the two regimes is statistically significant. [source]


    An Emerging Market's Reaction to Initial Modified Audit Opinions: Evidence from the Shanghai Stock Exchange,

    CONTEMPORARY ACCOUNTING RESEARCH, Issue 3 2000
    CHARLES J. P. CHEN
    Abstract This study investigates the valuation effect of modified audit opinions (MAOs) on the emerging Chinese stock market. Here, the term MAO refers to both qualified opinions and unqualified opinions with explanatory notes. The latter can be considered an alternative form of a qualified opinion in China. The institutional setting in China enables us to find compelling evidence in support of the monitoring role of independent auditing as an institution. First, we find a significantly negative association between MAOs and cumulative abnormal returns after controlling for effects of other concurrent announcements. Further, results from a by-year analysis suggest that investors did not reach negative consensus about MAOs' valuation effect until the second year, exhibiting the learning process of a market without prior exposure to MAOs. Second, we do not observe significant differences between market reaction to non-GAAP- and GAAP-violation-related MAOs. Third, no significant difference is found between market reaction to qualified opinions and market reaction to unqualified opinions with explanatory notes. [source]


    Corporate Boards and Company Performance: review of research in light of recent reforms

    CORPORATE GOVERNANCE, Issue 5 2007
    David Finegold
    Recent US corporate governance reforms introduced extensive regulations and guidelines for public corporations, particularly corporate boards. This article evaluates the extent to which empirical research on corporate boards and firm performance supports these reforms. Building on the meta-analysis conducted by Zahra and Pearce (1989), we review 105 studies published between 1989 and 2005. We find most of the practices mandated by the Sarbanes-Oxley Act of 2002, and the regulations issued by the New York Stock Exchange (NYSE) and the NASDAQ, had not been subject to prior study. Where board characteristics have been studied, we find limited guidance for policymakers on identifying governance practices that result in more effective firm performance. In an effort to increase the relevance of future research on boards and firm performance, we provide a framework on corporate boards. [source]


    Ownership Concentration and Corporate Performance on the Budapest Stock Exchange: do too many cooks spoil the goulash?

    CORPORATE GOVERNANCE, Issue 2 2005
    John S. Earle
    We examine the impact of ownership concentration on firm performance using panel data for firms listed on the Budapest Stock Exchange, where ownership tends to be highly concentrated and frequently involves multiple blocks. Fixed-effects estimates imply that the size of the largest block increases profitability and efficiency strongly and monotonically, but the effects of total blockholdings are much smaller and statistically insignificant. Controlling for the size of the largest block, point estimates of the marginal effects of additional blocks are negative. The results suggest that the marginal costs of concentration may outweigh the benefits when the increased concentration involves "too many cooks". [source]


    Principles of Corporate Governance in Greece

    CORPORATE GOVERNANCE, Issue 2 2001
    Harilaos Mertzanis
    This article presents the reasons which led the business community in Greece to reconsider existing corporate governance practices of listed corporations in the Athens Stock Exchange, outlines the general rationale for the creation and adoption of specific recommendations for best corporate practice, presents the recommendations in full detail and finally provides suggestions for the required corporate legal reform. [source]


    Trust and Innovation: from Spin-Off Idea to Stock Exchange

    CREATIVITY AND INNOVATION MANAGEMENT, Issue 2 2004
    Marko Kohtamäki
    Trust among entrepreneurs, their co-workers and between the entrepreneurs and their business partners plays a key role in the early stages of formation of a new company. In this piece of research, trust is defined as a belief consisting of eight trusting beliefs, emphasising the rational consideration between these beliefs and other situational factors. The concept of trust is developed through objects, mechanisms and antecedents. The present paper is an empirical exploration of these phenomena in the context of innovativeness in a high-tech company. The goal is to describe the role, content and impact of trust at the different stages of a business evolution process. [source]


    Distance Learning Video Grid: Online Teacher Exchange,

    DECISION SCIENCES JOURNAL OF INNOVATIVE EDUCATION, Issue 2 2009
    Roger McHaney
    First page of article [source]


    Directed Matching and Monetary Exchange

    ECONOMETRICA, Issue 3 2003
    Dean Corbae
    We develop a model of monetary exchange where, as in the random matching literature, agents trade bilaterally and not through centralized markets. Rather than assuming they match exogenously and at random, however, we determine who meets whom as part of the equilibrium. We show how to formalize this process of directed matching in dynamic models with double coincidence problems, and present several examples and applications that illustrate how the approach can be used in monetary theory. Some of our results are similar to those in the random matching literature; others differ significantly. [source]


    The Role of Political Instability in Stock Market Development and Economic Growth: The Case of Greece

    ECONOMIC NOTES, Issue 3 2000
    Dimitrios Asteriou
    This article examines empirically the relationship between stock market development, political instability and economic growth in Greece. We measure socio-political instability by constructing an index which captures the occurrence of various phenomena of political violence using time-series data. The main advantages of analysing political instability in a case study framework using time-series, in contrast with the widely used cross-country empirical studies, are: (a) a more careful and in-depth examination of institutional and historical characteristics of a particular country; (b) the use of a data set comprised of the most appropriate and highest quality measures; and (c) a more detailed exposition of the dynamic evolution of the economy. The empirical results indicate the existence of a strong negative relationship between uncertain socio-political conditions and the general index of the Athens Stock Exchange (ASE) and support the theoretical hypothesis that uncertain socio-political conditions affect economic growth negatively, is true for the Greek case. (J.E.L.: G10, G14, O40, C32) [source]


    Going Dutch in London City Comedy: Economies of Sexual and Sacred Exchange in John Marston's The Dutch Courtesan (1605)

    ENGLISH LITERARY RENAISSANCE, Issue 1 2010
    Marjorie Rubright
    Conventional approaches to London city comedy have explored the genre's dependence upon character types. Through a consideration of the ways in which English and Dutch ethnicity is represented in city comedy, this essay reveals that a critical and methodological revision is necessary. In John Marston's The Dutch Courtesan and Thomas Middleton's The Family of Love, puns and double entendres vivify characterizations of Dutchness and Englishness as unstable and problematically proximate. What emerges is a study of the chiastic interplay of differences and similarities that constitute Englishness and Dutchness in London city comedy. I argue that across the Anglo-Dutch relation identity was more of an analogous phenomenon than a digital one. In tracing how English-identified characters "go Dutch," this essay argues that city comedy was actively exploring and keeping in play the fluidity of signifiers of ethnic difference, especially language, diet, and religious belief. (M.R.) [source]


    Methylmercury uptake and distribution kinetics in sheepshead minnows, Cyprinodon variegatus, after exposure to CH3Hg-spiked food

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2004
    Joy J. Leaner
    Abstract The distribution kinetics of methylmercury (CH3Hg[II]) was determined in sheepshead minnows (Cyprinodon variegatus) after a single dose of different CH3Hg(II)-spiked food to determine what factors influence the bioavailability, uptake, and redistribution of CH3Hg(II) to various organs of C. variegatus. The kinetics of CH3Hg(II) distribution was measured in the different organs during a period of 0.1 to 35 d after dosage. The CH3Hg(II) distribution kinetics in the different tissues was modeled using a simple multicompartmental pharmacokinetic model, which assumed that blood was the conduit linking the CH3Hg(II) exchange between the different organs. The CH3Hg(II) was taken up into the intestinal tissue within hours after feeding, followed by a slow release to the blood and the other organs of the body. Exchange between the blood and the visceral organs was relatively slow, with maximum CH3Hg(II) uptake in the liver and gill occurring at 1.5 d following dietary exposure. Subsequently, the majority of the CH3Hg(II) was channeled from the viscera to the rest of the body with a substantial lag time after feeding. However, the rate of transfer between tissues in the studies reported here were faster than those measured by others for larger fish. [source]


    Adjustment of Temporal Call Usage During Vocal Exchange of Coo Calls in Japanese Macaques

    ETHOLOGY, Issue 6 2007
    Hideki Sugiura
    Japanese macaques (Macaca fuscata) exchange coo calls with group members to maintain contact. I examined the relationship between the distance between group members and (1) the latency of vocal responses to spontaneous calls, and (2) the latency of spontaneous call repetition in the absence of vocal responses. After a subject monkey's spontaneous call, the latency of vocal response by another group member was longer when the subject was farther from the group members than when the subject was near the group members. Furthermore, subject repeated calls with longer intervals in the absence of vocal response, which suggests that they wait longer for the vocal responses of other group members when the expected response latency is longer. These results reveal that Japanese macaques flexibly alter the timing of their calls based on others' vocal responses. [source]


    On the Magnet Effect of Price Limits

    EUROPEAN FINANCIAL MANAGEMENT, Issue 5 2007
    David Abad
    G1; G14; D44 Abstract The ,magnet' or ,gravitational' effect hypothesis asserts that, when trading halts are rule-based, investors concerned with a likely impediment to trade advance trades in time. This behaviour actually pushes prices further towards the limit. Empirical studies about the magnet effect are scarce, most likely because of the unavailability of data on rule-based halts. In this paper, we use a large database from the Spanish Stock Exchange (SSE), which combines intraday stock specific price limits and short-lived rule-based call auctions to stabilise prices, to test this hypothesis. The SSE is particularly well suited to test the magnet effect hypothesis since trading halts are price-triggered and, therefore, predictable to some extent. Still, the SSE microstructure presents two particularities: (i) a limit-hit triggers an automatic switch to an alternative trading mechanism, a call auction, rather than a pure halt; (ii) the trading halt only lasts 5 minutes. We find that, even when prices are within a very short distance to the price limits, the probability of observing a limit-hit is unexpectedly low. Additionally, prices either initiate reversion (non limit-hit days) or slow down gradually (limit-hit days) as they come near the intraday limits. Finally, the most aggressive traders progressively become more patient as prices approach the limits. Therefore, both the price patterns and the trading behaviour reported near the limits do not agree with the price limits acting as magnetic fields. Consequently, we conclude that the switching mechanism implemented in the SSE does not induce traders to advance their trading programs in time. [source]


    The Effect of Crossing-Network Trading on Dealer Market's Bid-Ask Spreads

    EUROPEAN FINANCIAL MANAGEMENT, Issue 2 2006
    Carole Gresse
    G19 Abstract This article provides new insights into market competition between traditional exchanges and alternative trading systems in Europe. It investigates the relationship between the trading activity of a crossing network (CN) and the liquidity of a traditional dealer market (DM) by comparing data from the SEAQ quote-driven segment of the London Stock Exchange (LSE) and internal data from the POSIT crossing network. A cross-sectional analysis of bid-ask spreads shows that DM spreads are negatively related to CN executions. Risk-sharing benefits from CN trading dominate fragmentation and cream-skimming costs. Further, risk-sharing gains are found to be related to dealer trading in the CN. [source]


    Competition on the London Stock Exchange

    EUROPEAN FINANCIAL MANAGEMENT, Issue 4 2002
    Nicholas Taylor
    This paper investigates the determinants of the level of competition on the order,driven market organised by the London Stock Exchange. In contrast to previous empirical market microstructure studies, we treat the level of competition as an endogenous variable. The statistical nature of the measures of competitive activity used in this paper necessitate use of a count regression model. Using a sample 50 stocks, we find that users of the system tend to follow the lead of other users (termed the ,herding effect') and that competition is greater during the period when the US exchanges are open (termed the ,US effect'). In addition, the level of competition is positively related to the bid,ask spread pertaining to a particular stock (termed the ,spread effect'). The latter result is most likely due to traders following a strategy where trade immediacy is traded off against price advantage. Finally, we find that the magnitude of the herding effect, the spread effect, and the fit of the count regression models (termed the ,fit effect') vary in a predictable manner across the liquidity of stocks. [source]


    Short-run Returns around the Trades of Corporate Insiders on the London Stock Exchange

    EUROPEAN FINANCIAL MANAGEMENT, Issue 1 2002
    Sylvain Friederich
    Previous work examined the long-run profitability of strategies mimicking the trades company directors in the shares of their own company, as a way of testing for market efficiency. The current paper examines patterns in abnormal returns in the days around these trades on the London Stock Exchange. We find movements in returns that are consistent with directors engaging in short-term market timing. We also report that some types of trades have superior predictive content over future returns. In particular, medium-sized trades are more informative for short-term returns than large ones, consistent with Barclay and Warner's (1993) ,stealth trading' hypothesis whereby informed traders avoid trading in blocks. Another contribution of this study is to properly adjust the abnormal return estimates for microstructure (spread) transactions costs using daily bid-ask spread data. On a net basis, we find that abnormal returns all but disappear. [source]


    [Re6Q7O(3,5-Me2PzH)6]Br2·3,5-Me2PzH (Q = S, Se) , New Octahedral Rhenium Cluster Complexes with Organic Ligands: Original Synthetic Approach and Unexpected Ligand Exchange in the Cluster Core

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 4 2005
    Yuri V. Mironov
    Abstract Two new octahedral rhenium cluster complexes, [Re6S7O(3,5-Me2PzH)6]Br2·3,5-Me2PzH (1) and [Re6Se7O(3,5-Me2PzH)6]Br2·3,5-Me2PzH (2), with the organic ligand 3,5-dimethylpyrazole (3,5-Me2PzH), have been synthesised by reaction of rhenium chalcobromides Cs3[Re6(µ3 -Q7Br)Br6] (Q = S, Se) with molten dimethylpyrazole. During the reaction, all six apical bromine ligands of the cluster complexes are substituted by the organic ligand, which is coordinated through the aromatic nitrogen atom N2. Additionally, the inner ligand µ3 -Br in the cluster core [Re6(µ3 -Q7Br)]3+ is substituted by oxygen, giving cluster cores [Re6(µ3 -Q7O)]2+ with mixed chalcogen/oxygen ligands. Compounds 1 and 2 have been characterised by single-crystal X-ray diffraction analysis. They are isostructural and crystallise with four formula units in the unit cell. Absorption spectra and luminescence characteristics of these two cluster compounds have been investigated in methanol. Absorption starts below 400 nm. For both compounds, broad emissions were found. The fluorescence decays of the two compounds follow a diexponential decay behaviour. The main fluorescence intensity decays have longer fluorescence lifetimes of 3.07 ± 0.03 (1) and 3.96 ± 0.02 µs (2). Studying the thermal stability of both compounds in vacuo showed that the release of 3,5-dimethylpyrazole ligands begins near 200 °C, and decomposition, with the removal of 7 molecules of 3,5-Me2PzH, is complete at 330 °C. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]


    Transition-Metal-Free Synthesis of Perdeuterated Imidazolium Ionic Liquids by Alkylation and H/D Exchange

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 17 2008
    Ralf Giernoth
    Abstract Economic, transition-metal-free syntheses of partially or completely deuterated imidazolium ionic liquids (ILs) were developed. Double alkylation starting from imidazole afforded side-chain deuterated imidazolium ionic liquids, which subsequently were fully deuterated by H/D-exchange on the cation ring. Isotopic exchange was studied for a range of ionic liquids, solvents and bases. Here, the presence of small amounts of basic impurities was found to significantly affect the exchange behaviour.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Protective Effect of HOE642, a Selective Blocker of Na+ -H+ Exchange, Against the Development of Rigor Contracture in Rat Ventricular Myocytes

    EXPERIMENTAL PHYSIOLOGY, Issue 1 2000
    Marisol Ruiz-Meana
    The objective of this study was to investigate the effect of Na+ -H+ exchange (NHE) and HCO3, -Na+ symport inhibition on the development of rigor contracture. Freshly isolated adult rat cardiomyocytes were subjected to 60 min metabolic inhibition (MI) and 5 min re-energization (Rx). The effects of perfusion of HCO3, or HCO3, -free buffer with or without the NHE inhibitor HOE642 (7 ,M) were investigated during MI and Rx. In HCO3, -free conditions, HOE642 reduced the percentage of cells developing rigor during MI from 79 ± 1% to 40 ± 4% (P < 0.001) without modifying the time at which rigor appeared. This resulted in a 30% reduction of hypercontracture during Rx (P < 0.01). The presence of HCO3, abolished the protective effect of HOE642 against rigor. Cells that had developed rigor underwent hypercontracture during Rx independently of treatment allocation. Ratiofluorescence measurement demonstrated that the rise in cytosolic Ca2+ (fura-2) occurred only after the onset of rigor, and was not influenced by HOE642. NHE inhibition did not modify Na+ rise (SBFI) during MI, but exaggerated the initial fall of intracellular pH (BCEFC). In conclusion, HOE642 has a protective effect against rigor during energy deprivation, but only when HCO3, -dependent transporters are inhibited. This effect is independent of changes in cytosolic Na+ or Ca2+ concentrations. [source]


    Limit Order Adjustment Mechanisms and Ex-Dividend Day Stock Price Behavior

    FINANCIAL MANAGEMENT, Issue 3 2005
    Keith Jakob
    Unlike the NYSE, the Toronto Stock Exchange (TSX) does not adjust prices in the outstanding limit orders on ex-dividend days. We find that TSX ex-day stock price behavior differs from that on the NYSE in several key aspects. In each case, the TSX ex-day behavior is consistent with the lack of a limit order adjustment mechanism. Our findings confirm that market microstructure is an important factor that contributes to the observed Canadian ex-day price behavior. Our findings also resolve the puzzle of the relatively small ex-day price drop in Canada. [source]


    Determinants of Investor Demand for Cross-Listed Firms

    FINANCIAL MARKETS, INSTITUTIONS & INSTRUMENTS, Issue 3 2010
    George Athanassakos
    G11; G12; G15 By focusing on the decisions of investors to invest in cross-listed stocks, this paper presents new evidence on why we observe striking differences in the percentage of trade in foreign markets for cross-listed stocks. With a large sample of Toronto Stock Exchange (TSX) stocks cross-listed in the U.S. and Canada, we document the effect of investor recognition and risk characteristics on the distribution of trading volume. Firms that are more visible to American investors are traded more heavily in the U.S. At the same time, firms that offer diverse risk characteristics are attractive to Americans. While investors understand the benefits of international diversification, as they are attracted to stocks that are different (e.g., the stock of small firms with few assets in the U.S.), they also seek stocks that provide them with high returns. [source]