bluuebunny/crossref_metadata_2025 huggingface dataset:
THE NONPARALLEL WEEKEND EFFECT IN THE STOCK AND BOND MARKETS
Authors: Singleton J. Clay , Wingender John R.
Published: August 2014

Explanations for the day‐of‐the‐week effect are either market‐specific conventions (timing delays in settlement and clearing, dividend payout arrangements) or cross‐market events (bad news delayed until the weekend). Although a market‐specific rational is confined to one market, cross‐market events affect at least two markets. In this research we investigate the weekend effect in the stock and Treasury markets. Our findings suggest the weekend effect is nonparallel across financial markets. Thus, the weekend effect is more likely due to unique features of the individual markets than to events affecting both stock and Treasury markets simultaneously.
COMMERCIAL BANK RISK: MARKET, INTEREST RATE, AND FOREIGN EXCHANGE
Authors: Wetmore Jill L. , Brick John R.
Published: August 2014

Because of recent structural changes in the balance sheets of banks, regulatory changes in the risk‐based capital requirements, and the recent adoption of mark‐to‐market accounting changes, interest rate risk remains an important issue for commercial banks and an important regulatory concern. Market, interest rate, and foreign exchange risk are estimated for a sample of commercial banks using ordinary least squares from 1986 to 1991. Consistent with earlier studies, the estimated coefficients continue to be unstable. We find that interest rate risk decreases and foreign exchange risk increases. Moreover, the results differ depending on practices of the bank (money center, superregional, or regional). We find evidence consistent with earlier studies that theorize foreign exchange risk is explained by unhedged foreign loan exposure.
TIME‐SERIES PROPERTIES OF THE EQUITY RISK PREMIUM
Authors: Clinebell John M. , Kahl Douglas R. , Stevens Jerry L.
Published: August 2014

In this paper we use time‐series models to investigate the presence of autoregression, random variation, and random walk movements of historic equity risk premiums. An autoregressive risk premium is found for 1926–58, but random variation around a much lower risk premium mean is found for 1959–90. This finding is not sensitive to holding‐period length, the choice of the risk‐free rate proxy, or January/July seasonal effects.
THE CHANGING RISK PROFILE OF U.S.‐BASED MULTINATIONAL CORPORATIONS EXPOSED TO EUROPEAN COMMUNITY MARKETS
Authors: Chambliss Karen , Madura Jeff , Wright Francis W.
Published: August 2014

In this study we investigate the risk characteristics of U.S.‐based multinational corporations (MNCs) that conduct much of their business in the European Community. Specifically, we assess the efficacy of a multifactor return‐generating model that incorporates the influence of U.S. and European markets. Our results demonstrate that the European market is a significant factor in explaining the time‐series behavior of MNC returns, and that the European market influence is stronger since the adoption of the Single European Act. In addition, the reduction in the sensitivity of MNCs to the U.S. market since the Single European Act is cross‐sectionally associated with changes in their proportional levels of European sales. The results suggest that the returns of other MNCs expanding into increasingly integrated regional blocs may experience similar changes in their systematic risk profile.
THE WEALTH EFFECTS OF ANNOUNCEMENTS OF R&D EXPENDITURE INCREASES
Authors: Zantout Zaher Z. , Tsetsekos George P.
Published: August 2014

We examine the effect of announcements of plans to increase R&D expenditures on the stock price of rival firms. We test two alternative hypotheses: the first‐to‐innovate hypothesis versus the free‐rider of spillovers hypothesis. Analysis of 114 announcements of increases in R&D expenditures indicates that rival firms suffer a statistically significant negative abnormal return at announcement, which supports the first‐to‐innovate hypothesis. This result provides a rationale for the potentially costly voluntary disclosure of R&D expenditures. A cross‐sectional analysis of the abnormal returns to rival firms reveals that a highly credible announcement has some spillover effects, and that the rival firm earns a much smaller but positive abnormal return. An important implication is that it is always strategically beneficial for the firm to disclose its future R&D plan.
OPEN MARKET STOCK REPURCHASE PROGRAMS AND LIQUIDITY
Authors: Wiggins James B.
Published: August 2014

In this paper I examine the behavior of bid and ask spreads and depths around announcements of open market stock repurchase programs. For a sample of 195 announcements from 1988 to 1990, I find statistically significant evidence of a small decline in spreads and no evidence of a shift in depths following the announcement date. Results are similar for a subsample of firms experiencing post‐announcement declines in the number of shares outstanding. I conclude that open market repurchase programs as used recently do not adversely affect market liquidity.
VARIANCE, RETURN, AND HIGH‐LOW PRICE SPREADS
Authors: Lin Ji‐Chai , Rozeff Michael S.
Published: August 2014

We report three new findings that rely upon the high‐low price range as an estimate of stock return variance. The predictability of variance is associated with persistence in high prices and with correlated shocks to high and low prices. Excess stock returns are positively related to anticipated variance and inversely related to unanticipated variance. Lagged squared residuals in GARCH(1,1) models have no incremental explanatory power in the presence of forecasts of conditional volatility generated from high‐low price spread models.
THE VALUATION EFFECTS OF FREQUENT COMMON STOCK ISSUANCES
Authors: McDaniel Wm R , Madura Jeff , Akhigbe Aigbe
Published: August 2014

Previous empirical studies show that announcements of seasoned common stock registrations and issuances lead to significant reductions in common stock prices and shareholder wealth. Nevertheless, some firms issue common stock frequently. Our empirical study of nonutility firms that issued common stock four or more times within ten years shows that market reactions to announcements of offerings and to registrations are less unfavorable than typical reactions for infrequent issuers. A cross‐sectional analysis reveals no unique characteristics that distinguish frequent issuers from one‐time common equity issuers. In fact, the only detectable characteristic unique to the firms is that they issue common stock frequently.
THE INFLUENCE OF ORGANIZED OPTIONS TRADING ON STOCK PRICE BEHAVIOR FOLLOWING LARGE ONE‐DAY STOCK PRICE DECLINES
Authors: Peterson David R.
Published: August 2014

In this study I examine the effect of organized options trading on stock price behavior immediately following stock price declines of 10 percent or more. A matched‐pair sample of National Market System option and nonoption firms are analyzed from June 1985 through December 1992. After controlling for the bid‐ask bounce, firm size, share price, return standard deviation, and beta, I find that three‐day cumulative abnormal returns for option firms are approximately 1.57 percent less than those for nonoption firms. Thus, options trading enhances stock market efficiency and/or liquidity. However, no profitable trading strategies are indicated.
DETERMINANTS OF PERSISTENCE IN RELATIVE PERFORMANCE OF MUTUAL FUNDS
Authors: Volkman David A. , Wohar Mark E.
Published: August 2014

Similar to previous studies, we investigate the relation between past and future fund performance. However, we deviate from previous studies by investigating the relation between persistent fund performance and four systematic factors: size, goal, load, and management fee. Results indicate no consistent relation between fund size and persistent fund performance. The existence of a sales charge does not affect persistent fund performance. The goal of a fund does affect persistent fund performance, with high‐risk maximum capital gain funds' demonstrating a strong positive persistence in abnormal returns. In addition, funds with low management fees demonstrate significantly positive persistent fund performance, while funds with high management fees demonstrate significantly negative persistent fund performance. Further research into the relation between persistent fund performance and maximum capital gain funds indicates persistent fund performance in both inferior‐ and superior‐performing funds. However, persistence in funds with low management fees occurs only in funds with superior past performance.
MACROECONOMIC VARIABLES AND SEASONAL MEAN REVERSION IN STOCK RETURNS
Authors: Gangopadhyay Partha
Published: August 2014

In this paper I investigate whether seasonal mean reversion in stock portfolio returns is related to common macroeconomic risk factors. I decompose excess returns into explained and unexplained returns using a multifactor pricing model. The explained excess returns exhibit January mean reversion; the unexplained excess returns do not. The mean reversion can be attributed to the components of return related to unexpected inflation, bond default premium, and market risk. The results do not depend on the time‐series properties of the portfolio betas. Bond default premia and excess market returns are mean reverting in January.
LEVERAGE, RISK‐SHIFTING INCENTIVE, AND STOCK‐BASED COMPENSATION
Authors: Harikumar T.
Published: August 2014

Outstanding risky debt provides risk‐shifting incentives for managers fully aligned with stockholders. Earlier research shows that the risk‐shifting incentive can be eliminated by using a stock‐based compensation design to align managers' and stockholders' interests. I show that stock options as well as compensation designs that align managers' and bondholders' interests eliminate the risk‐shifting incentive. Although a stock‐based compensation design is not a unique mechanism to eliminate the pure risk‐shifting incentive, it is essential where managers of levered firms are known to consume a portion of the investment outlay as perquisites.
WEALTH EFFECTS OF ENFORCEMENT ACTIONS AGAINST FINANCIALLY DISTRESSED BANKS
Authors: Brous Peter A. , Leggett Keith
Published: August 2014

We examine the stock price reaction for a sample of commercial banks to the signing of cease‐and‐desist orders, written agreements, and formal agreements with bank regulators. These agreements restrict financially distressed institutions from certain activities that may be perceived by the capital markets as favorable or unfavorable. Our finding of a significantly negative mean signing‐day abnormal return suggests that these enforcement actions are not fully anticipated by the market and that, on average, these enforcement actions are perceived as being unfavorable for bank shareholders. Our cross‐sectional analysis suggests that at least part of the negative market reaction is caused by a reduction in the moral hazard problem associated with financially distressed federally insured commercial banks. Although these actions are beneficial to both the federal deposit insurer and ultimately taxpayers, we interpret the cross‐sectional findings as implying that regulators are not acting in a timely fashion to restore the financial health of these distressed “banks. Even though equity values fall, on average, when banks are faced with an enforcement action, our findings do not support the pre‐FIRREA policy not to publicly disclose the signing of enforcement actions because the enforcement action itself is not the source but is merely a reflection of the bank's problems.
WHO GAINS FROM CORPORATE ASSET SALES?
Authors: Datta Sudip , Iskandar‐Datta Mai E.
Published: August 2014

This study documents that sell‐offs, on average, are firm value enhancing, as both stockholders and bondholders gain from such transactions. Further, it reveals that sell‐offs can be wealth redistributing, value destroying, or value enhancing depending on the way the sale proceeds are distributed and the motive underlying the sell‐off. The wealth effects on stockholders and bondholders are not always symmetrical. Our results suggest that benefits from the sale of assets that do not strategically fit the firm's core business accrue primarily to stockholders, while benefits from distress‐related sell‐offs accrue to bondholders. Sell‐offs to thwart takeovers destroy firm value. We document that a significant proportion of sell‐offs results in wealth transfers between securityholders. Restrictive dividend covenants play an important role in protecting bondholders from wealth expropriation. Our analysis suggests that the relative size of the asset sale, the uses of the sale proceeds, and the degree of protection afforded bondholders via a dividend restriction may be relevant in explaining the direction of wealth transfer.
SKEWNESS AND KURTOSIS IN S&P 500 INDEX RETURNS IMPLIED BY OPTION PRICES
Authors: Corrado Charles J. , Su Tie
Published: August 2014

The Black‐Scholes (1973) model frequently misprices deep‐in‐the‐money and deep‐out‐of‐the‐money options. Practitioners popularly refer to these strike price biases as volatility smiles. In this paper we examine a method to extend the Black‐Scholes model to account for biases induced by nonnormal skewness and kurtosis in stock return distributions. The method adapts a Gram‐Charlier series expansion of the normal density function to provide skewness and kurtosis adjustment terms for the Black‐Scholes formula. Using this method, we estimate option‐implied coefficients of skewness and kurtosis in S&P 500 stock index returns. We find significant nonnormal skewness and kurtosis implied by option prices.
THE SURVIVAL OF INITIAL PUBLIC OFFERINGS IN THE AFTERMARKET
Authors: Hensler Douglas A. , Rutherford Ronald C. , Springer Thomas M.
Published: August 2014

We estimate an accelerated failure time (AFT) model to investigate the effects of several characteristics suggested as indicators of firm survival for initial public offerings (IPOs). The results indicate that the survival time for IPOs increases with size, age of the firm at the offering, the initial return, IPO activity level in the market, and the percentage of insider ownership, while the survival time decreases with increases in the general market level at the time of the offering and the number of risk characteristics. Additionally, the survival time is negatively affected if the IPO is in the computer and data, wholesale, restaurant, or airline industries and positively affected if the IPO is in the optical or drug industries.
THE VALUE OF A REGULATORY SEAL OF APPROVAL
Authors: Gupta Atul
Published: August 2014

I investigate whether obtaining a regulatory seal of approval adds to firm value. For a sample of thirty‐four firms that acquired the insured deposits of failed banks, I find a significantly greater price response for firms that could benefit from obtaining a regulatory seal of approval than for firms that had recently obtained a similar form of approval. Further, abnormal returns to winning bidders are significantly larger when a regulatory seal of approval is likely to be more valuable, i.e., when the industry faces severe economic problems. In addition, bidder gains are significant only in markets where regulatory certification of a firm's health is important—markets that have recently experienced several bank failures. Finally, wealth transfers from the FDIC insurance fund may contribute to bidder gains. The evidence suggests that obtaining a regulatory seal of approval can positively affect firm value.
COGNITIVE DISSONANCE AND MUTUAL FUND INVESTORS
Authors: Goetzmann William N. , Peles Nadav
Published: August 2014

We present evidence from questionnaire responses of mutual fund investors about recollections of past fund performance. We find that investor memories exhibit a positive bias, consistent with current psychological models. We find that the degree of bias is conditional upon previous investor choice, a phenomenon related to the well‐known theory of cognitive dissonance. Psychological and economic frictions in the mutual fund industry are examined via a cross‐sectional study of equity mutual funds. We find an unusually high frequency of poorly performing funds, consistent with investor “inertia.” We also examine the differential responses of investment dollars to past performance, controlling for survivorship. These show that the effect is confined to the top quartile. We find little evidence that the response to poor performance is unusual.
THE EFFECT OF FDICIA REGULATION ON BANK HOLDING COMPANIES
Authors: Carow Kenneth A. , Larsen Glen A.
Published: August 2014

We examine market reactions to legislative announcements surrounding the passage of the Federal Deposit Insurance Corporation Improvement Act (FDICIA) of 1991. Research shows that bank regulation adversely affects shareholder wealth on the one hand, yet often provides government subsidies on the other. The removal of Federal regulators' discretionary authority and the imposition of mandatory regulations in the FDICIA have an overall negative effect on our sample of bank holding companies. The results are consistent with either the costly regulation hypothesis or the decreased subsidies hypothesis.
BANKING RELATIONSHIPS AND THE EFFECT OF MONITORING ON LOAN PRICING
Authors: Blackwell David W. , Winters Drew B.
Published: August 2014

In a sample of bank loans to small firms we find a positive relation between the bank's monitoring effort and the loan's interest rate. We also observe an inverse relation between the closeness of banking relationships and interest rates. Further, we see that banks less frequently monitor firms with whom they have closer relationships. We conclude that banking relationships are valuable because firms can significantly reduce their costs of capital by establishing and maintaining close ties to a particular bank. As firms successfully complete loan transactions with banks, banks monitor them less frequently and, ultimately, charge them lower interest rates.
OPTIMAL BIDDING FOR TENDER OFFERS
Authors: Khanna Naveen
Published: August 2014

By modeling tender offers as auctions in which bidders arrive sequentially, I show that the first bidder includes a high premium in its opening bid in an attempt to freeze out potential competitors. When expected competition goes up, the premium offered increases as does target shareholder welfare, while bidders suffer. Also, total synergy gains generated increase with competition. Including a premium in the opening bid remains optimal for the first bidder when target management is permitted to resist. Target management's ability to resist, though, benefits target shareholders even when resistance is not actually observed. When agency costs are introduced, the effect of managerial resistance on target shareholder welfare becomes ambiguous.
CHANGES IN MARKET PERCEPTION OF RISKINESS: THE CASE OF TOO‐BIG‐TO‐FAIL
Authors: Black Harold A. , Collins M. Cary , Robinson Breck L. , Schweitzer Robert L.
Published: August 2014

In 1984, the Comptroller of the Currency stated that the eleven largest banking firms were “too big to fail,” implying they would receive de facto 100 percent deposit insurance. The question is whether this announcement altered the market's perception of the riskiness of all banking organizations, not just those included in the Comptroller's statement. We address this question with two tests. First, through the examination of changes in institutional equity ownership from 1980 through 1988, we find that the announcement is associated with increases in institutional ownership at a time when a comparable set of nonfinancial firms saw reductions in institutional holdings. Second, through the examination of stock returns behavior of bank holding companies around announcements of dividend cuts and omissions from 1974 through 1991, we find that the Comptroller's 1984 announcement altered the market's reaction to dividend cuts and omissions by bank holding companies not specifically included in the Comptroller's statement.
INVESTMENT OPPORTUNITIES AND MULTINATIONALITY: EVIDENCE FROM CAPITAL STRUCTURE CHANGES
Authors: Rahman Manzur
Published: August 2014

I examine shareholder valuation effects of capital structure changes for multinational (MNC) and domestic (DC) corporations. The internalization theory of foreign direct investment posits that MNCs create value by internalizing the market for their assets across national borders. If the financing decision is related to the rents from future investments, MNCs may have differential valuation effects to capital structure changes vis‐à‐vis DCs. I find that MNCs have lower (greater) excess returns for debt‐for‐equity (equity‐for‐debt) exchanges than DCs. The cross‐sectional analyses show that the valuation effects are differentially related to the investment opportunities of MNCs and DCs.
INTRA‐INDUSTRY EFFECTS OF BOND RATING ADJUSTMENTS
Authors: Akhigbe Aigbe , Madura Jeff , Whyte Ann Marie
Published: August 2014

Several studies find that bond rating downgrades cause negative valuation effects. Other studies find that signals conveyed by earnings releases, earnings forecasts, bankruptcies, and stock offerings of individual firms can be transmitted to their corresponding industries. By combining the two sets of studies, we hypothesize that bond rating changes may contain relevant information not only about the firm, but also about the corresponding industry. We find significantly negative valuation effects for rating downgrades, which are transmitted throughout the industry. Furthermore, we find that intra‐industry effects depend on particular characteristics of the bond downgrade, the downgraded firm, and industry rivals. Specifically, the negative intra‐industry effects are more pronounced when (1) the downgraded firm experiences a more severe share price response to the bond rating downgrade, (2) the downgraded firm is dominant in the industry, (3) the downgraded firm is more closely related to its rivals in the industry, and (4) the downgrade is due to a deterioration in the firm's financial prospects.
THE MARKET REACTION TO STRAIGHT DEBT ISSUES: THE EFFECTS OF FREE CASH FLOW
Authors: Howton Shawn D. , Howton Shelly W. , Perfect Steven B.
Published: August 2014

In this paper we measure the market reaction to 937 straight debt issues between 1983 and 1993. We find a negative and significant market reaction to a straight debt announcement. In addition, we find that the market reaction to a straight debt issue is directly related to the issuing firm's level of existing cash and inversely related to the issuing firm's investment opportunities.
INFORMATION TRANSMISSION IN THE SHANGHAI EQUITY MARKET
Authors: Long D. Michael , Payne Janet D. , Feng Chenyang
Published: August 2014

We examine market efficiency and the price‐volume relation in Class A and Class B shares on the Shanghai exchange relative to the U. S. equity market. Variance ratios and runs tests for market efficiency support the hypothesis that both Class A and Class B markets follow a random walk. In addition, the augmented Dickey‐Fuller test supports the null hypothesis that the Shanghai market follows a random‐walk process with drift. We also find a significantly positive relation between changes in volume and absolute price returns in both Class A and Class B shares, which is consistent with studies on U.S. equity markets. However, when using signed returns, our results are stronger than most U.S. studies on price‐volume relations. We find no significant difference between the price‐volume correlations in Class A and Class B shares. However, the price‐volume correlations in both Class A and Class B shares are significantly stronger than the price‐volume correlation in the U.S. market. This suggests volume may be more important to information transmission in China than in the U. S. markets.
MAINBANKS AND INVESTMENT EFFICIENCY IN FINANCIAL DISTRESS
Authors: Reeb David M. , Kwok Chuck C. Y.
Published: August 2014

We explore the effects of mainbanks on investment efficiency in financial distress. The previous literature argues that firms with close financial relationships with banks have lower costs of financial distress because of a reduced underinvestment problem. Although benefits may accrue to such close relationships, we contend shortcomings are possible as well. A firm in financial distress without a mainbank may be forced to reduce investment or sell assets to a buyer who has a higher value. However, for a firm with a mainbank, this disciplinary force is weakened. To firms with poor investment opportunities, the presence of mainbanks may actually induce an overinvestment problem. The empirical findings reported here are consistent with this idea.

JEL classification: G31, G33, G34.
REGULATORY THREATS AND POLITICAL VULNERABILITY
Authors: Bowman Robert G. , Navissi Farshid , Burgess Richard C.
Published: August 2014

During the 1992 U.S. presidential campaign and immediately after, the pharmaceutical industry was subjected to regulatory threats. It was charged with high drug costs, high advertising expense, and insufficient expenditure on research and development (R&D) to develop better drugs. We examine whether firms' measures of political vulnerability (higher advertising expense and lower R&D expenditure) influence the equity value effects of the regulatory threats. We find negative announcement effects around three regulatory threats. We then extend the analysis and find evidence consistent with our hypotheses that measures of political vulnerability are associated with more negative abnormal returns in response to the regulatory threats.

JEL classification: G18, L50, L65.
A STATE‐SPACE MODEL OF SHORT‐ AND LONG‐HORIZON STOCK RETURNS
Authors: Zhou Chunsheng , Qing Chang
Published: August 2014

In this article we propose a new parsimonious state‐space model in which state variables characterize the stochastic movements of stock returns. Using the equally weighted and decile monthly stock returns, we show that (a) a parsimonious state‐space model characterizes the variation in expected returns at any horizon; (b) the extracted expected returns explain a substantial proportion of the variance in realized returns, and the magnitude of this proportion increases significantly with the horizon of returns; (c) the model successfully captures the empirical fact that returns of smaller firms have both stronger positive autocorrelations of short‐horizon returns and stronger negative autocorrelations of long‐horizon returns; and (d) the forecasts of asset returns obtained with the state‐space model subsume the information in other potential predictor variables such as dividend yields.

JEL classification: G10, G12.
BOOK REVIEWS
Authors: Vu Joseph D.
Published: August 2014

Floating‐Rate Securities, by Frank J. Fabozzi and Steven V. Mann. Frank J. Fabozzi Associates, 2000, 219 pages, suggested retail price $70.
VOLATILITY SPILLOVERS BETWEEN THE BLACK MARKET AND OFFICIAL MARKET FOR FOREIGN CURRENCY IN GREECE
Authors: Kanas Angelos , Kouretas Georgios P.
Published: August 2014

The issue of volatility spillovers between the black and official exchange markets for U.S. dollars in Greece for 1975–89 is examined. A vector error correction‐bivariate EGARCH model is developed and estimated to capture potential asymmetric effects of innovations and volatility. During the period under investigation, reciprocal spillovers are found between the black and official exchange markets for dollars. Furthermore, spillovers are asymmetric in that bad news in one market has a greater effect on the volatility of the other market than good news. Additionally, the size of spillover effects is greater from the official market to the black market. Finally, the removal of the foreign exchange controls in January 1986 made the volatility of the official exchange rate higher and changed the nature of volatility spillovers between the two markets.

JEL Classification: F31, F32
Understanding the Behavior of Native Point Defects in ZrC by First‐Principles Calculations
Authors: Zhang Yanhui , Wang Jiemin , Liu Bin , Wang Jingyang , Zhang Haibin
Published: August 2014

Phase stability and macroscopic performances of ZrC are closely related to the behavior of native point defects. In this study, structures and stabilities of native point defects in ZrC as well as diffusion of C‐related defects are investigated by first‐principles calculations. It is shown that the carbon vacancy (VC) and interstitials (Cis) are the dominant native point defects in ZrC. Six types of Ci configurations: two C‐trimers, one C‐tetrahedron, and three C‐dimers are identified with low defect formation energies. The VC has a high migration energy (4.39 eV) which suggests its low mobility in ZrC. The Cis have low diffusion energy barriers (from 0.26 to 1.29 eV) which lead to their high mobility. In addition, the impact of defects (VC, VZr, ZrC, and CZr) on bonding strengths of neighboring Zr–C bonds is discussed. Especially near VC, the 1NN (nearest neighboring) and 2NN Zr–C bonds are strengthened but 4NN Zr–C bonds are weakened. Interestingly, the 3NN Zr–C bonds are almost not affected by the presence of VC. These results may be closely related to the short‐range interactions and ordering of VC in nonstoichiometric ZrC.
A similar phylogeographical structure among sympatric North American birches (Betula) is better explained by introgression than by shared biogeographical history
Authors: Thomson Ashley M. , Dick Christopher W. , Dayanandan Selvadurai
Published: August 2014

Aim

A comparative analysis of the chloroplast (cp) DNA structure of eastern North American birches (Betula) was undertaken to infer the impacts of Quaternary climate change on the phylogeographical structure of these species.

Location

Eastern North America.

Methods

Genetic variation in chloroplast microsatellites (cpSSRs) and the psbA–trnH intergenic spacer in Betula papyrifera, Betula alleghaniensis and Betula lenta was analysed in samples from 65, 80 and 12 populations, respectively. Co‐occurring Betula uber, Betula populifolia and Betula cordifolia were also sampled to examine haplotype relationships and account for potential introgression. Haplotype networks, Bayesian analysis and comparisons of RST and GST values were used to evaluate the phylogeographical structure. Genetic diversity within and among species was compared using rarefaction analysis.

Results

The two most widespread species, B. papyrifera and B. alleghaniensis, showed high levels of haplotype diversity, while the Appalachian endemic B. lenta possessed a single haplotype. Bayesian analysis revealed three main phylogeographical groups for B. papyrifera and four groups for B. alleghaniensis, and these two species showed extensive regional haplotype sharing and a high introgression ratio.

Main conclusions

We postulate that at least three separate refugia contributed to the recolonization of B. papyrifera and B. alleghaniensis within eastern North America, while B. lenta appears to have recolonized from a single refugium. A high haplotype diversity of B. papyrifera and B. alleghaniensis in the Great Lakes region may reflect biogeographical contact between eastern and western lineages, with the potential influence of periglacial refugia. Similar phylogeographical patterns in the distantly related B. papyrifera and B. alleghaniensis represent a geographical turnover of the same locally shared haplotypes, pointing to introgression rather than shared biogeographical history as the mechanism. Although similar phylogeographical patterns are often interpreted as evidence for common biogeographical histories, our study demonstrates that such patterns can also arise through introgression.
Er:YAG laser versus scaling and root planing as alternative or adjuvant for chronic periodontitis treatment: a systematic review
Authors: Zhao Yanhui , Yin Yuanzheng , Tao Li , Nie Ping , Tang Yanmei , Zhu Min
Published: August 2014

Aim

To perform a systematic review to evaluate the erbium‐doped: yttrium, aluminium and garnet (Er:YAG) laser versus scaling and root planing (SRP) as alternative or adjuvant for chronic periodontitis treatment.

Material and Methods

We performed a literature search using six electronic databases and completed by manual searches up to July 2013. We conducted a meta‐analysis as well as heterogeneity, sensitivity, subgroup and power analyses to clarify and validate the pooled results. The 3‐, 6‐ and 12‐month clinical outcomes were evaluated.

Results

Twelve eligible randomized clinical trials were finally included. Our meta‐analysis showed that Er:YAG laser resulted in similar clinical improvements as SRP 3 months postoperatively. For subgroups by laser level, quality of trials and fluorescence feedback device, the results remained consistent. The 6‐ and 12‐month observations between Er:YaG laser and SRP demonstrated no difference but inconclusive, due to large heterogeneity. The advantage of Er:YAG laser adjuvant to SRP for periodontitis treatment was not significant.

Conclusions

This systematic review indicated that the clinical efficacy of Er:YAG laser was similar to SRP 3 months postoperatively. The clinical benefits of Er:YAG laser as adjuvant to SRP was still lacking. Since Er:YAG laser has certain advantages, it could be expected to be a novel short‐term alternative choice for chronic periodontitis.
Psychotic experiences co‐occur with sleep problems, negative affect and mental disorders in preadolescence
Authors: Jeppesen Pia , Clemmensen Lars , Munkholm Anja , Rimvall Martin K. , Rask Charlotte U. , Jørgensen Torben , Larsen Janne T. , Petersen Liselotte , van Os Jim , Skovgaard Anne M.
Published: August 2014

Background

Knowledge on the significance of childhood psychotic symptoms and experiences (PE) is still limited. This study aimed to investigate the prevalence and clinical significance of PE in preadolescent children from the general population by use of in‐depth psychopathological interviews and comprehensive diagnostic assessments.

Methods

We investigated 1,632 children from the general population‐based Copenhagen Child Cohort 2000. PE were measured by semistructured interviews using the K‐SADS‐PL‐items on psychotic and affective symptoms, each symptom scored as not present versus likely or definitely present. The Development and Well‐Being Assessment (DAWBA) was used independently to diagnose DSM‐IV‐mental disorders. Puberty development and sleep disturbance were self‐reported. The associations between PE (any lifetime hallucination and/or delusion) and various mental problems and disorders were examined by multivariable binomial regression analyses, adjusting for gender and onset of puberty.

Results

The weighted life time prevalence of PE at age 11–12 years was 10.9% (CI 9.1–12.7). The majority of children with PE (n = 172) either had a diagnosable DSM‐IV‐mental disorder (31.4%) or self‐reported mental health difficulties in absence of a diagnosis (31.4%). The risk of delusions increased with onset of puberty. The risk of PE increased with emotional and neurodevelopmental disorders, subthreshold depressive symptoms, sleep problems and lack of sleep, regardless of whether PE were expressed as hallucinations and/or delusions. The highest correlations were seen for emotional and multiple disorders.

Conclusions

Psychotic experiences are particularly prevalent in the context of affective dysregulation and sleep disturbance, increase with onset of puberty and represent a trans‐diagnostic marker of psychopathology.
Target and non‐target effects of a spider venom toxin produced in transgenic cotton and tobacco plants
Authors: Ullah I. , Hagenbucher S. , Álvarez‐Alfageme F. , Ashfaq M. , Romeis J.
Published: August 2014

The peptide ω‐Hexatoxin‐Hv1a (Hvt) is one of the most studied spider toxins. Its insecticidal potential has been reported against species belonging to the arthropod orders Lepidoptera, Diptera and Orthoptera. The gene encoding Hvt has been transformed into cotton and tobacco to protect the plants from damage by lepidopteran pests. This study evaluated the expression of the ω‐HXTX‐Hv1a gene in transgenic plants, and the toxicity of plant‐expressed and purified Hvt on target lepidopteran insects and on several non‐target species. Transgenic Bollgard II cotton plants, which produce Cry1Ac and Cry2Ab2 and purified Cry2Ab2 protein were included in the study as comparators. LC95 values of purified Hvt against Spodoptera littoralis and Heliothis virescens were 28.31 and 27.57 μg/ml of artificial diet, respectively. Larval mortality was 100% on Hvt‐transgenic tobacco plants but not on Hvt‐transgenic cotton, probably because of the significantly lower toxin expression level in the transgenic cotton line. Non‐target studies were conducted with larvae of the predators Chrysoperla carnea and Coccinella septempunctata, adults of the aphid parasitoid Aphidius colemani, and adult workers of the honey bee, Apis mellifera. Even at 40 μg/ml, Hvt did not adversely affect the four non‐target species. Purified Cry2Ab2 at 10 μg/ml also did not adversely affect any of the non‐target species. Our results show that Hvt might be useful for developing insecticidal plant varieties to control pest Lepidoptera.
Immunogenicity of hepatitis B vaccine in patients with inflammatory bowel disease and the benefits of revaccination
Authors: Cossio‐Gil Yolima , Martínez‐Gómez Xavier , Campins‐Martí Magda , Rodrigo‐Pendás José Ángel , Borruel‐Sainz Natalia , Rodríguez‐Frías Francisco , Casellas‐Jordà Francesc
Published: August 2014

Background and Aim

The vaccination against hepatitis B virus (HBV) is recommended in patients with inflammatory bowel disease (IBD). However, the response to this vaccine seems to be lower in IBD patients than in the general population. This study aims to evaluate the immunogenicity of the HBV vaccine in a cohort of patients with IBD, to associate factors with the response and to analyze the effects of a second schedule vaccination.

Methods

We conducted a retrospective cohort study of adults with IBD, susceptible to HBV infection. All patients received a three‐dose standard schedule of HBV vaccine. Non‐responders were revaccinated with a second three‐dose standard schedule. Adequate immunity to HBV was defined as antibodies against hepatitis B surface antigen (anti‐HBs) ≥ 10 mIU/mL. Age, comorbidities, treatment, and other variables were collected.

Results

One hundred seventy‐two patients were included and received the first HBV vaccine schedule. Eighty‐seven developed anti‐HBs ≥ 10 mIU/mL (50.6%; 95% confidence interval [CI]: 42.9–58.3). From the non‐responders, 53 were revaccinated and 28 showed an adequate serological response (52.8%; 95% CI: 38.6–66.7). Age older than 55 years (OR: 3.6; 95% CI: 1.3–10.2) and comorbidities (OR: 2.8; 95% CI: 1.1–7.1) were associated with suboptimal response. In the multivariate analysis, only age was a predictor of non‐response (age higher than 55 years; OR: 3.9; 95% CI: 1.3–11.9)

Conclusion

The response rate to the HBV vaccine is lower in patients with IBD compared with the general population, especially in those older than 55 years. Revaccination improved response rate by 50%.
Peace and Power: A Theory of Emancipatory Group Process
Authors: Chinn Peggy L. , Falk‐Rafael Adeline
Published: August 2014

Purpose

To present the theoretical basis for the group process known as “Peace and Power.”

Organizing Construct

A dialectic between two dominant forms of power—peace powers and power‐over powers—forms the basis for a synthesis that yields an emancipatory group process characterized by praxis, empowerment, awareness, cooperation, and evolvement for individuals and groups.

Methods

Critical analysis of prevailing competitive group dynamics and the ideals of cooperative group dynamics was conducted to project the potential for achieving group interactions that yield profound changes in the direction of justice, empowerment, and well‐being for all.

Conclusions

The theoretical framework of “Peace and Power” is consistent with characteristics of emancipatory integrity that are vital for social change.

Clinical Relevance

The processes of “Peace and Power” can be used to create peaceful, cooperative interactions among nurses, with other health professionals, with patients and families, and in communities.
Career Cartography: A Conceptualization of Career Development to Advance Health and Policy
Authors: Feetham Suzanne , Doering Jennifer J.
Published: August 2014

Purpose

The purpose of this article is to propose a conceptualization of career development that emphasizes the interdependence between research, practice, and policy.

Organizing Construct

Career cartography applies three decades of career development experience to lay out a systematic, comprehensive, and iterative approach for planning and communicating the outcomes of science at any career stage. To inform practice and policy, nurse researchers must be clear on the intended destination and trajectory of the science, and be skilled in communicating that science and vision to diverse stakeholders. Career cartography builds on the science of cartography, is developed within the context of public and health policy, and is composed of several components, including a destination statement, career mapping, a supportive career cartography team, and use of communication and dissemination strategies.

Conclusions

The successful utilization of career cartography may accelerate advancement of individual careers, scientific impact, and the discipline as a whole by guiding nurse researchers to be deliberative in career planning and to communicate successfully the outcomes of research across a wide variety of stakeholders. Career cartography provides a framework for planning a nurse researcher's program of research and scholarship to advance science, policy, and health of the public.

Clinical Relevance

Career cartography guides nurse researchers to realize their full potential to advance the health of the public and inform public and health policy in academic and practice environments.
Effects of patient position on lower extremity venous pressure during different types of hysterectomy
Authors: Liu Xiaoxia , Wang Xiaohong , Meng Xianhua , Wang Hongping , An Zengshun
Published: August 2014

Aim

To explore the effects of different types of hysterectomy on lower extremity venous pressure.

Methods

Ninety‐nine patients with benign uterine diseases who were indicated for hysterectomy were included in the present prospective study. Patients were divided into three groups according to their preferences: (i) total laparoscopic hysterectomy (TLH) group (n = 36); (ii) transvaginal hysterectomy (TVH) group (n = 32); and (iii) transabdominal hysterectomy (TAH) group (n = 31). Lower extremity venous pressure was monitored using a pressure sensor during the surgery.

Results

Compared with the supine position (TAH group, lower extremity venous pressure of intraoperative 16.50 cmH2O), lower extremity venous pressure of the improved lithotomy position (TLH group, lower extremity venous pressure of intraoperative 53.27 cmH2O) and conventional lithotomy position (TVH group, lower extremity venous pressure of intraoperative 42.09 cmH2O) were significantly increased (P < 0.01).Venous pressure was reduced when patients lowered their heads by 15° or 5° in modified or conventional lithotomy positions, respectively (P < 0.01). Venous pressure was increased significantly after the establishment of pneumoperitoneum in the TLH group (P < 0.01).

Conclusion

Modified lithotomy position (TLH group) and conventional lithotomy position (TVH group) and CO2 pneumoperitoneum may result in increased lower extremity venous pressure during hysterectomy. Furthermore, elevated venous pressure can be altered by changing the intraoperative position. Specifically, intraoperative positioning of the lower extremities represents a modifiable risk factor for deep venous thrombosis.
On the Centrality of Action: Social Science, Historical Logics, and Max Weber's Legacy
Authors: Malczewski Eric
Published: August 2014

This article draws attention to the fundamental centrality of “action” – i.e. symbolically constituted behavior – for the historical and social sciences. The work of Max Weber and contemporary American historian and theorist William H. Sewell, Jr. are examined, so as to shed light on the debate concerning social science's central subject matter as well as on the implications of this work for sociological and historical theory. The examination of Sewell's view leverages the importance of the concept of action underlying Weber's concept of “social action.” Weber's position on action and social action is of great interest not only to general theory but also to the field of cultural sociology, which has neglected to develop systematically upon the theoretical purchase Weber offers to it.
Genitourinary Syndrome of Menopause: New Terminology for Vulvovaginal Atrophy from the International Society for the Study of Women's Sexual Health and The North American Menopause Society
Authors: Portman David J. , Gass Margery L.S. , Vulvovaginal Atrophy Terminology Consensus Conference Panel
Published: August 2014

Introduction

The terminology for the genitourinary tract symptoms related to menopause was vulvovaginal atrophy, which does not accurately describe the symptoms nor is a term that resonates well with patients.

Aim

In 2012, the Board of Directors of the International Society for the Study of Women's Sexual Health (ISSWSH) and the Board of Trustees of The North American Menopause Society (NAMS) acknowledged the need to review current terminology associated with genitourinary tract symptoms related to menopause.

Methods

The two societies cosponsored a terminology consensus conference, which was held in May 2013.

Main Outcome Measure

The development of a new terminology that more accurately described the genitourinary tract symptoms related to menopause.

Results

Members of the consensus conference agreed that the term genitourinary syndrome of menopause (GSM) is a medically more accurate, all-encompassing, and publicly acceptable term than vulvovaginal atrophy. GSM is defined as a collection of symptoms and signs associated with a decrease in estrogen and other sex steroids involving changes to the labia majora/minora, clitoris, vestibule/introitus, vagina, urethra, and bladder. The syndrome may include but is not limited to genital symptoms of dryness, burning, and irritation; sexual symptoms of lack of lubrication, discomfort or pain, and impaired function; and urinary symptoms of urgency, dysuria, and recurrent urinary tract infections. Women may present with some or all of the signs and symptoms, which must be bothersome and should not be better accounted for by another diagnosis.

Conclusion

The term GSM was presented and discussed at the annual meeting of each society. The respective Boards of NAMS and ISSWSH formally endorsed the new terminology—genitourinary syndrome of menopause—in 2014.
Languages As Categories: Reframing the “One Language or Two” Question in Early Bilingual Development
Authors: Byers‐Heinlein Krista
Published: August 2014

One of the most enduring questions in the field of bilingualism is whether bilingual infants and children initially have one language system or two. Research with adults indicates that, while bilinguals do not represent their languages in two fully encapsulated language systems, they are able to functionally differentiate their languages. This article proposes that bilinguals differentiate their languages insofar as they can treat elements of their languages as belonging to different categories. Several lines of research with bilingual adults and children are considered in the context of perceptual and conceptual language categories. The article ends with a discussion of how language categories might emerge over the course of early bilingual development and outlines directions for future research.