bluuebunny/crossref_metadata_2025 huggingface dataset:
Successful antitakeover defenses, top management turnover and stock prices
Authors: Duggal Rakesh , Cudd Mike
Published: May 2007

Previous studies have not addressed the question of whether successful targets of hostile bids adopt specific defenses, or whether a relation exists between the type of defense and subsequent management turnover. This study finds that sale or buyback of stock is the most common‐and probably the most successful‐form of defense employed by targets to defeat hostile bidders, and that stock buyback leads to management retrenchment in the post‐defeat period. The management turnover announcement has no impact on the target stock price and appears to convey no new information to the market.
Intra‐industry structure and the response toward rivals
Authors: Peteraf Margaret A.
Published: May 2007

This paper is a study of the pricing behavior of airline monopolists toward potential entrant carriers from different strategic groups. The results suggest that formerly regulated carriers price lower when faced by potential entrants from the newly certified carrier group than they do when they face only potential entrants from their own group. These results are consistent with the heretofore‐untested hypothesis from Caves and Porter (1977) and Porter (1979) that rivalry is greater across groups than within groups.
Profit opportunities with the American put‐call parity when dividends are not expected
Authors: Frankfurter George M. , Leung W. K.
Published: May 2007

The objective of this research is to study borrowing and lending profit opportunities with the put‐call parity of American options when dividends on the stock are not expected. Studying profit opportunities embedded in the put‐call parity is intriguing because of their relative simplicity. The only assumptions necessary for the parity to hold are that option markets are frictionless and generate efficient prices of puts and calls around the underlying stock price. For this reason alone (parsimony of postulates) the put‐call parity is a tempting vehicle for studying option market efficiency. In this work it is shown that both synthetic lending and borrowing parities (before and after transaction costs), on average and ex post, have negative expected profits (i.e. put‐call parity implied rates are inferior to the observed riskless rate). When certain trading rules are established, however, empirical evidence of substantial profit opportunities with both lending and borrowing with the American parity (even after considering transaction costs) is observed. It is also shown that these opportunities are greater for some stocks than for others. The existence of these disparities might be an indication that the pricing mechanism of the respective options is not always in sync. The duration of disequilibrium between the options market and the stock market suggests that such occurrences are not just random bursts.
The effects of marginal changes of ownership on multi‐level objectives in corporate groups
Authors: Kornbluth J. S. H. , Salkin G. R.
Published: May 2007

Changes in the intra‐group linkages affect the ownership of members of the group by their parents and can have different effects on the various objectives of the group. This paper shows how one can use the standard formula for calculating ownership in a group of companies to derive a linear approximation to the marginal changes in the group structure as the result of changes in intra‐group linkages. These marginal effects can be used in linear multi‐objective and/or decentralized planning systems in the group. An example is provided on some tax‐planning effects of marginal changes of intra‐group ownership.
Supplier incentives and resource constraints under uncertainty
Authors: Seshadri Sudhindra
Published: May 2007

Procurement in environments of cost uncertainty and asymmetric information require special arrangements such as the linear incentive contract. Usually the buyer is motivated to make investments that can relieve temporary supplier resource constraints during the procurement. Special problems arise, however, due to interactions between investments in suppliers and the risk‐incentive trade‐off achieved by the incentive contract. A cost signaling model is proposed to overcome these problems, where a supplier offers an equity share in the profit from the incentive contract to the buyer in return for a priori investment. The equity share signals the supplier's private cost information, and forms the basis for the buyer's investment decision. Under equilibrium the buyer can expect to recover the entire amount provided to the supplier through his or her share of the profit.
Management's reporting strategy and imperfection of the capital market
Authors: Tzur Joseph , Yaari Varda (Lewinstein)
Published: May 2007

Since the decision on the reported outcome is delegated to the management of the firm, it is commonly held that when the capital market is imperfect the manager achieves consumption smoothing by smoothing the reports relative to the actual outcome. Modeling the firm as a principal‐agent contract shows the contrary. When the capital market is imperfect the firm's reporting strategy is conservative, as the manager never reports more than the actual outcome because of fear of an unfavorable future outcome. When the capital market is perfect the firm either smooths the report‐reports more than the actual outcome when the actual outcome is low and reports less than the actual outcome when the outcome is hig‐or reports more than the actual outcome in order to take advantage of the sharing rule being an increasing function of the report.
Price rigidity: An exploration of the demand side
Authors: Roufagalas John
Published: May 2007

This paper presents an exploration of the demand‐side effects of unanticipated price changes. Consumers faced with these changes may have to reoptimize their income allocation. Reoptimization is costly, and reoptimization costs result in kinked demand curves. The existence of such kinked demands provides an additional explanation of the observed nominal price rigidity. In addition, examination of unexpected nominal price changes during inflationary periods provides some justification as to why nominal price adjustments are large, infrequent and almost never downward.
International acquisitions in the united states: Evidence from returns to foreign bidders
Authors: Mathur Ike , Rangan Nanda , Chhachhi Indudeep , Sundaram Sridhar
Published: May 2007

This paper provides evidence on the minimally explored topic of abnormal returns earned by stockholders of foreign bidders seeking to acquire a target firm in the USA. Four sources of influence on abnormal returns are identified: changes in net wealth of the bidder associated with changes in exchange rates; possible value‐destroying managerial discretionary behavior by bidders with excess cash flows, as suggested by Jensen; comparative advantages for foreign bidders domiciled in relatively favorable tax jurisdictions; ownership status of the target, i.e. whether the target is an entire firm and whether it involves divested assets. The study includes 77 firms from 10 countries. The results show that stockholders of foreign bidders earn significant, negative abnormal returns surrounding the announcement of an acquisition in the USA. These abnormal returns become increasingly negative over the 15 days after the announcement of the acquisition, indicating that more information about the acquisition is revealed to investors subsequent to the initial announcement. Cross‐sectional regressions indicate that relative exchange rates and cash positions explain variation in abnormal returns. A decline in the value of the dollar increases abnormal returns for the foreign bidder, thus supporting the net wealth hypothesis. The results also show that cash‐rich foreign firms tend to enjoy higher abnormal returns when making acquisitions in the USA. The result provides support for the Froot and Stein cash‐constrained hypothesis rather than for Jensen's free‐cash‐flow theory.
Explaining Downstream Integration
Authors: Majumdar Sumit K. , Ramaswamy Venkatram
Published: May 2007

We examine the downstream integration decision by businesses, deriving hypotheses from the transaction cost literature which are empirically tested for a sample of 1392 businesses operating in a wide spectrum of industries. Our results provide corroboration for each dimension of the transaction cost framework in explaining why firms might integrate their downstream business activities. Given the large cross‐sectional sample, our results provide some evidence of the general validity of the transaction cost framework within the context of downstream integration.
R&D spillovers and innovative activity
Authors: Acs Zoltan J. , Audretsch David B. , Feldman Maryann P.
Published: May 2007

The new learning has raised a number of explanations why smaller enterprises may, in fact, tend to have an innovative advantage, at least in certain industries. The purpose of this paper is to identify the degree to which university and corporate R&D spills over to innovative activity at the state level. We find substantial evidence that spillovers are facilitated by the geographic coincidence of universities and research laboratories within the state.
The dividend policies of all‐equity firms: A direct test of the free cash flow theory
Authors: Agrawal Anup , Jayaraman Narayanan
Published: May 2007

This paper finds support for Jensen's (1986) hypothesis that dividends and debt are substitute mechanisms for controlling the agency costs of free cash flow. We find that dividend payout ratios of a sample of all‐equity firms are significantly higher than those of a control group of levered firms. Further, within the group of all‐equity firms, firms with lower managerial holdings have higher payout ratios. These results hold after controlling for free cash flow and growth rates. Overall, our evidence suggests that dividends and managerial ownership are substitute mechanisms for reducing agency costs in all‐equity firms.
Managerial efficiency and survivability in professional team sports
Authors: Scully Gerald W.
Published: May 2007

Students of organizational sociology tend to believe that managerial efficiency has less to do with individual talent than with the environment in which firms operate. Economists and fans know that this is not true in sports. Measures of managerial efficiency are constructed for baseball, basketball and football coaches. Survival analysis is utilized to measure coaching tenure probabilities in these sports and coaching tenure is shown to be related to managerial efficiency.
Major league baseball division standings, sports journalists' predictions and player salaries
Authors: Smyth David J. , Smyth Seamus J.
Published: May 2007

This paper analyzes the accuracy of predictions of division baseball winners and rankings for the 1982 to 1990 seasons. The forecasts in Sport, Sports Illustrated and the New York Times are more accurate than purely random forecasts except at predicting the National League winners. The journalists are better at predicting division winners, but not division rankings, than a naive model that assumes this season's rankings, will be the same as last seasons's. Combining the forecasts in the three publications does not result in greater forecasting accuracy. A model that uses the relative average salaries of teams significantly outperforms the journalists at predicting division rankings and, when allowance is made for ‘George Steinbrenner effect’, also at predicting division winners.
Bargaining power and the structure of salaries in major league Baseball
Authors: Marburger Daniel R.
Published: May 2007

The relationship between bargaining power and the structure of salaries in major league baseball has been a subject of much empirical study. The evidence provided in this paper suggests that eligibility for final‐offer arbitration does not result in a ‘fixed’ reduction in monopsonistic exploitation. Rather, the level of exploitation diminishes markedly in the first season of eligibility and continues to decrease in subsequent seasons. By the time the player reaches free agency eligibility, he can expect to earn the same single‐season salary that he would as a free agent.
Do anti‐ticket scalping laws make a difference?
Authors: Williams Andrew T.
Published: May 2007

Ticket scalping is the practice of buying tickets at one price and reselling them at a higher one. The practice is controversial and currently almost half the states regulate the resale of tickets to one degree or another. As with other laws that regulate economic activity, the question immediately arises: ‘Who benefits from the law?’ Economists typically view transactions between willing buyers and willing sellers, such as ticket scalping, as welfare improving. They also view any interference with free market transactions as suspect and as possible evidence of rent harvesting. In an attempt to quantify the economic impact of anti‐ticket scalping laws this paper presents a regression model of ticket price determination for National Football League teams and uses it to test the proposition ‘Do anti‐ticket scalping laws make a difference?’
A common‐trends and error‐correction approach to forecasting corporate bond returns
Authors: Taylor William M.
Published: May 2007

It is found that one unit root, common trend, is shared by the monthly price indices of the top four ratings of corporate bonds. Addition of an index of low‐grade bonds to the vector time series results in two common trends. Consistent results are provided by dynamic factor analyses. The returns for the system of cointegrated indices can be represpnted by an error‐correction model using past returns and cointegrating vectors. This model can provide more accurate forecasts than a common VAR that omits the cointegrating vectors. The common‐trends analysis provides specific linear combinations, or cointegrating portfolios, of the index price levels that are stationary. The cointegrating portfolios associated with the two common trends have returns that are related to T‐bill returns and unanticipated inflation.
The design of executive stock options
Authors: Young Leslie , Quintero Socorro M.
Published: May 2007

A contract between manager and shareholder comprising salary plus options which are sometimes out of the money implies less risky managerial income but weaker incentives than a contract comprising salary plus stocks (or options which are always in the money) which leaves the manager as well off. Increasing the exercise Price and the salary so that (1) there are some states where the options cannot be exercised but (2) the manager is as well off as before always leads initially to a reduction in effort which outweighs any gains from improved risk sharing, leaving the shareholder worse off.
Vertical mergers and the balance of trade
Authors: Pan Chih‐Min
Published: May 2007

This paper examines the relationship between the vertical merger and the balance of trade. Our results show that the effects of the vertical merger on the trade balance and consumers' welfare depend on the production technology adopted by the final good manufacturers. The vertical merger will improve both the trade balance and consumers' welfare when fixed‐coefficient technology is adopted. However, these positive effects could not be held when variable‐coefficient technology is used to produce the final good.
A model for risk classification of banks
Authors: Kumar Sameer , Arora Sant
Published: May 2007

This paper deals with designing a bank risk classification scheme based on readily available performance data. This risk rating is referred to as ‘Risk rating’. Due to non‐availability of data on CAMEL rating (C rating), R risk rating has potential for studying risk‐based premiums insurance policy and for determining optimal frequencies for variable frequency on‐site examination policy. A composite non‐performance measure is developed to estimate probability of failure of a bank based on performance data available in bank call reports by fitting a Logit curve and estimating its parameters using maximum likelihood method. Division of banks into healthy and watchful types is based on critical dividing value of probability of failure.
The impact of institutional stockholders and managerial interests on the capital structure of firms
Authors: Firth Michael
Published: May 2007

When the self‐interests of management and stockholders conflict, this is likely to manifest itself in different attitudes towards risk. Managers are hypothesized to desire low levels of debt in the firm's capital structure, while outside stockholders, who hold diversified portfolios, will tolerate higher debt ratios. Empirical results provide evidence in support of the hypotheses. The presence of institutional investors constrains management's discretion in setting capital structure and a positive relationship is identified between their fractional and dollar‐value ownership of a firm and debt‐assets ratios. Institutional investors will act in a manner that is consistent with the goals of other outside stockholders.
Strategic management under duopoly
Authors: Hwang Hong , Mai Chao‐Cheng
Published: May 2007

The purpose of this paper is to present a general conjectural variation model to provide an integrative treatment of strategic management under duopoly. It is shown that the nature of the desired distortion of managers' incentives depends critically on the magnitudes of the managers' conjectural variations with respect to outputs as well as the owners' conjectural variations with respect to incentives. In particular, it has been demonstrated that when the owners' conjectural variations with respect to incentives are zero, the owners will motivate their managers to maximize profits and provide no incentives for sales under consistent conjectures. However, the owners make their managers behave more (less) aggressively and produce more (less) than profit‐maximizers if the managers' conjectural variations with respect to outputs are larger (smaller) than the actual response.
Innovation, market structure and firm size: A simultaneous equations model
Authors: Koeller C. Timothy
Published: May 2007

This study uses a hwequation model and data for four‐digit SIC manufacturing industries to examine the joint endogeneily of output measures of innovation activity and market structure (industry concentration). Its results confirm recent studies finding high concentration to have a negative effect on innovation output (especially smabfinn innovations), and Anding that large‐firm innovations and small‐finn innovations respond Werently to economic and technological conditions. The study also reveals that, contrary to some previous research, and consistent with modern ‘Schumpeterian’ propositions, innovation output (especially largefirm innovations) has a significant positive effect on industry concentration.
Venture capitalist participation and the post‐issue operating performance of IPO firms
Authors: Jain Bharat A. , Kini Omesh
Published: May 2007

Previous studies have identified the value‐added potential of venture capitalist monitoring in the initial public offering (IPO) market. We test this proposition by comparing the post‐issue operating performance of venture capitalist‐backed IPOs with a matched sample of non‐venture capitalist‐backed IPOs. We find that venture capitalist‐backed IPO firms exhibit relatively superior post‐issue operating performance compared to non‐venture capital‐backed IPO firms. Further, the market appears to recognize the value of monitoring by venture capitalists as reflected in the higher valuations at the time of the IPO. Finally, we find that proxies for the quality of venture capitalist monitoring are positively related to post‐issue operating performance.
Insolvency, moral hazard and expense preference behavior: Evidence from US savings and loan associations
Authors: Gropper Daniel M. , Beard T. Randolph
Published: May 2007

This article applies the expense preference methodology to a study of determinants of employee compensation and occupancy costs for large samples of mutual and stock savings and loan associations. Strong evidence that insolvency is associated with significant increases in these costs is obtained. Further, we find that the effect of insolvency on managerial expense preference behavior is more pronounced for mutual than stock associations.
A classroom exercise on executive incentive compensation schemes
Authors: Elitzur R. Ramy
Published: May 2007

This paper describes a classroom exercise that has been used in several graduate courses. The exercise provides the students with a framework for understanding the rationale behind some of the mechanisms we observe in reality: incentive compensation plans for executives, Generally Accepted Accounting Principles (GAAP), auditing, and lawsuits against auditors. As such, the exercise provides some answers for several questions of ‘why’ before getting into the ‘how’ of reporting. The case can be used in courses dealing with financial accounting, managerial control and microeconomics in the MBA level.
Non‐isothermal plasticity model for cyclic behaviour of soils
Authors: Laloui L. , Cekerevac C.
Published: May 2007

On the one hand, it has been observed that liquefaction‐induced shear deformation of soils accumulates in a cycle‐by‐cycle pattern. On the other hand, it is known that heating could induce plastic hardening. This study deals with the constitutive modelling of the effect that heat may have on the cyclic mechanical properties of cohesive soils, a relatively new area of interest in soil mechanics. In this paper, after a presentation of the thermo‐mechanical framework, a non‐isothermal plasticity cyclic model formulation is presented and discussed. The model calibration is described based on data from laboratory sample tests. It includes numerical simulations of triaxial shear tests at various constant temperatures. Then, the model predictions are compared with experimental results and discussed in the final section. Both drained and undrained loading conditions are considered. The proposed constitutive model shows good ability to capture the characteristic features of behaviour. Copyright © 2007 John Wiley & Sons, Ltd.
Gain and overexpression of the oncostatin M receptor occur frequently in cervical squamous cell carcinoma and are associated with adverse clinical outcome
Authors: Ng G , Winder D , Muralidhar B , Gooding E , Roberts I , Pett M , Mukherjee G , Huang J , Coleman N
Published: May 2007

For many oncogenes, increased expression resulting from copy number gain confers a selective advantage to cells that consequently make up the tumour bulk. To identify oncogenes of potential biological significance in cervical squamous cell carcinoma (SCC), 36 primary samples and ten cell lines were screened by array comparative genomic hybridization (CGH). The most commonly occurring regions of copy number gain that also showed amplification were 5p15.2–14.3 (59%), 5p13.3 (65%), and 5p13.2–13.1 (63%). Gene copy numbers were significantly associated with expression levels for three candidate oncogenes at these loci: OSMR (oncostatin M receptor) (p = 0.03), PDZK3 (PDZ domain containing protein 3) (p = 0.04), and TRIO (triple functional domain) (p = 0.03). Further examination by fluorescence in situ hybridization on a tissue microarray of 110 primary cervical SCC samples revealed copy number gain frequencies of 60.9%, 57.3%, and 54.5% for OSMR, PDZK3, and TRIO, respectively, with OSMR adversely influencing overall patient survival independently of tumour stage (p = 0.046). By array CGH, copy number gain of OSMR was not seen in any of 40 microdissected precursor cervical squamous intraepithelial lesions (SILs). Moreover, global mRNA expression analysis, using Affymetrix U133A 2.0 Arrays, showed no overexpression of OSMR in SILs, suggesting that OSMR gain and overexpression are relatively late steps in cervical carcinogenesis. In the cervical SCC cell lines CaSki and SW756, exogenous OSM activated downstream‐signalling elements of OSMR including STAT3, p44/42 MAPK, and S6 ribosomal protein, and induced transcription of the angiogenic factor VEGF, effects that were reduced by OSMR depletion using RNA interference. We conclude that copy number gain of OSMR is frequently found in cervical SCC and is associated with adverse clinical outcome. As well as being a potential prognostic marker, OSMR is a candidate cell surface therapeutic target. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Evaluating instructional programs: How much is enough?
Authors: Markle Susan M.
Published: May 2007

Instructional developers need to determine the degree of economically justifiable rigor for evaluating instructional products. Rigorous evaluation, involving outside evaluators, random assignment of masses of individuals from well‐defined populations, and massive amounts of data, is often beyond their means. At the opposite extreme, representing no evaluation at all desite the size of consumer market, are most standard educational materials. A successive approximations scheme to empirical determination of effectiveness is needed, with consumers aware of the risks involved. The fear to “teaching to the test” (recently termed “wholly indefensible”) conflics with the basic assumptions of the teachonology of instruction and with the achievement of accountability of the instructional system to its consumers.
Proteomics strategy based on liquid‐phase IEF and 2‐D DIGE: Application to bone marrow mesenchymal progenitor cells
Authors: Seshi Beerelli
Published: May 2007

Global comparative proteomics is a promising new approach with broad application in basic and clinical biological science. Recent advances include the development of 2‐D DIGE, a proteomic equivalent to mRNA differential display, in which differentially labeled samples are multiplexed and analyzed by high‐resolution 2‐DE. This study presents a new 2‐D DIGE protocol, in which complex protein samples from normal and leukemic human bone marrow mesenchymal progenitor cells were used as model samples for a novel combination of liquid‐phase IEF with 2‐D DIGE. Using liquid‐phase IEF, the normal and leukemic cells were pre‐fractionated into five subproteomes after multiplexing but prior to DIGE. Under these conditions, 2‐D DIGE resolved >5000 protein‐containing spots within the pH range 4.6–7.0. Differential labeling combined with subsequent MALDI‐MS/MS identified proteins that were differentially expressed in leukemic cells. This analysis mapped protein identities to 128 mesenchymal progenitor cell proteins with at least one unique peptide match at >95% confidence. Of these proteins, 72 (56%) were expressed more than 1.25‐fold higher or lower in leukemic cells compared with normal cells (p<0.05). These data were used to infer gene ontology biological processes that may be altered in leukemic bone marrow mesenchymal progenitor cells.
A rapid mass spectrometric strategy for the characterization of N‐ and O‐glycan chains in the diagnosis of defects in glycan biosynthesis
Authors: Faid Valegh , Chirat Frédéric , Seta Nathalie , Foulquier François , Morelle Willy
Published: May 2007

Glycosylation of proteins is a very complex process which involves numerous factors such as enzymes or transporters. A defect in one of these factors in glycan biosynthetic pathways leads to dramatic disorders named congenital disorders of glycosylation (CDG). CDG can affect the biosynthesis of not only protein N‐glycans but also O‐glycans. The structural analysis of glycans on serum glycoproteins is essential to solving the defect. For this reason, we propose in this paper a strategy for the simultaneous characterization of both N‐ and O‐glycan chains isolated from the serum glycoproteins. The serum (20 μL) is used for the characterization of N‐glycans which are released by enzymatic digestion with PNGase F. O‐glycans are chemically released by reductive elimination from whole serum glycoproteins using 10 μL of the serum. Using strategies based on mass spectrometric analysis, the structures of N‐ and O‐glycan chains are defined. These strategies were applied on the sera from one patient with CDG type IIa, and one patient with a mild form of congenital disorder of glycosylation type II (CDG‐II) that is caused by a deficiency in the Cog1 subunit of the complex.
Electronic states related to dislocations in silicon
Authors: Cavalcoli D. , Cavallini A.
Published: May 2007

Dislocations and impurities in silicon, even though studied since many years, are now subject of a renewed interest. Moreover, many question related to dislocation‐ related electronic states remain still unsolved. The present contribution reviews several results, obtained by the authors, on dislocation impurity interactions and their effects on the electronic properties of defect states in silicon. Dislocations introduced by plastic deformation and oxygen precipitation in p‐type Czochralski (Cz) silicon have been investigated by junction spectroscopy methods. A deep hole trap, named T1, has been associated to dislocation‐related impurity centers, while additional deep traps have been related to contamination by grown‐in transition metals and to clusters involving oxygen atoms. Moreover, experimental results obtained by junction spectroscopy assessed the existence of dislocation related shallow states. These were found to be located at 70 and 60 meV from the valence and conduction band edge, respectively. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Plasticity and deformation microstructure of 4H‐SiC below the brittle‐to‐ductile transition
Authors: Mussi A. , Rabier J. , Thilly L. , Demenet J. L.
Published: May 2007

Compression tests under confining pressure are performed with a Paterson press in order to deform 4H‐SiC plastically below the brittle‐to‐ductile transition temperature. Deformation microstructure in this regime is analysed using conventional and high resolution transmission electron microscopy and is compared with literature. Leading partial dislocations with carbon core and silicon core are observed on basal plane as well as perfect dislocations out of the basal plane. Double stacking faults are evidenced in the deformed microstructure. These original observations indicate that the deformation microstructures of 4H‐SiC in the brittle domain are more complex than previously reported. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative study of quantum efficiency of blue LED with different nanostructural arrangement
Authors: Greshnov A. A. , Chernyakov A. E. , Ber B. Y. , Davydov D. V. , Kovarskyi A. P. , Shmidt N. M. , Snegov F. M. , Soltanovich O. A. , Vergeles P. S. , Yakimov E. B. , Zakgeim A. L.
Published: May 2007

Current–voltage characteristics and quantum efficiency dependence on injected current for blue light emitting diodes with different nanostructural arrangement were studied. The Electron Beam Induced Current (EBIC) technique was used to monitor the hole recombination inside the quantum wells and to reveal the lateral inhomogeneities in the recombination velocity. The bright EBIC contrast associated with extended defects was revealed. This contrast was explained by a formation of channels with enhanced conductivity near the extended defects penetrating the active device region. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High resolution imaging of extended defects in GaN using wave function reconstruction
Authors: Niermann T. , Kocan M. , Roever M. , Mai D. , Malindretos J. , Rizzi A. , Seibt M.
Published: May 2007

Imaging of extended defects at atomic resolution using high‐resolution transmission electron micrography (HRTEM) is problematic due to the lens aberrations of an uncorrected microscope and the loss of the phase during recording of images. As a result, techniques to measure the strain fields of these defects can only be applied under distinct and well‐controlled conditions sometimes in a narrow window of specimen thickness and imaging conditions. Using a combination of focal series reconstruction and numerically correction of the lens aberrations a‐posteriori allows overcoming these limitations. Also the strain fields can be measured using geometrical phase analysis without further precaution. We will demonstrate the application of these techniques on extended defects found in GaN. A discrepancy between the theoretically predicted structure of the Ga‐terminated 90°‐partial and the experimentally observed one has been put in evidence. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bulk micro defects behaviour in not‐intentionally contaminated epi Si submitted to relaxation and segregation gettering
Authors: Frigeri C. , Gombia E. , Motta A.
Published: May 2007

An EBIC study of bulk micro defects (BMDs) in not‐intentionally contaminated epi Si submitted to both relaxation and segregation gettering and with an unknown initial contaminant concentration below the sensitivity of DLTS has been carried out. It allowed to establish which was the contaminant (Fe) and the possible range of its initial concentration. An evaluation of the behaviour of the BMDs during relaxation gettering and of the contribution of relaxation gettering to the overall gettering process was performed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dislocation‐related electronic states in partially strain‐relaxed InGaAs/GaAs heterostructures grown by MOVPE
Authors: Gelczuk Ł. , Dąbrowska‐Szata M. , Jóźwiak G. , Radziewicz D. , Serafińczuk J. , Dłużewski P.
Published: May 2007

By means of deep level transient spectroscopy (DLTS) a dislocation‐related deep‐level trap has been revealed in partially strain‐relaxed InGaAs/GaAs heterostructures, grown by MOVPE. On the basis of the specific criteria containing DLTS‐line shape and behaviour analysis as well as capture kinetics measurements, we were able to attribute the trap to “localized” states at the dislocation core or close to it. A direct comparison of DLTS concentration profiles and TEM results enable us to attribute the electron trap to 60° misfit dislocations lying at the heterostructure interface. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth peculiarities of silicon nanoparticles in an oxide matrix prepared by magnetron sputtering
Authors: Khomenkova L. , Bulakh B. , Korsunska N. , Stara T. , Goldstein Y. , Jedrzejewski J. , Savir E. , Sada C. , Bisello D. , Khomenkov V. , Emirov Yu.
Published: May 2007

The process of thermal decomposition of SiOx layers prepared by magnetron sputtering is studied by photoluminescence, AFM, Auger and SIMS methods. The dependence of the depth distribution of the chemical composition on excess silicon content is obtained. It is shown that as‐sputtered SiOx layers are characterized by homogeneous enough chemical composition and do not exhibit photoluminescence. High‐temperature annealing in nitrogen atmosphere stimulates not only Si nanoparticle formation but also the appearance of a Si depleted region near layer‐substrate interface. This last process is found to be dependent on excess Si content. The decrease of silicon content in the depth of the annealed layers is accompanied by the decrease of Si particle sizes as proved by the blue shift of the photoluminescence maximum. The mechanisms of SiOx decomposition and possible reasons for the appearance of the Si depleted region are discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of dislocation decoration with mobile donors on exciton luminescence in ZnO crystals
Authors: Markevich I. V. , Kushnirenko V. I. , Borkovska L. V. , Bulakh B. M. , Rusavsky A. V.
Published: May 2007

In ZnO single crystals, the influence of grown‐in and introduced by mechanical damage dislocations on room temperature exciton luminescence was investigated. It was found that the higher dislocation density the weaker the luminescence and the lower the intensity of its short‐wavelength side with respect to that of long‐wavelength one. After introduction of dislocations, gradual quenching of exciton luminescence and the suppression of its short‐wavelength side took place. Observed effects were accounted for by the formation of optical absorption “tail” due to decoration of dislocations with mobile shallow donors, which resulted in the increase of reabsorption of emitted light in the crystal. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evolution of nitrogen pairs and nitrogen‐oxygen complexes in nitrogen‐doped Czochralski silicon
Authors: Li Ming , Yang Deren , Ma Xiangyang , Cui Can , Que Duanlin
Published: May 2007

By means of Fourier‐transform infrared absorption spectroscopy, the evolution of nitrogen pairs (N‐N) and nitrogen‐oxygen complex (NNO) in nitrogen doped Czochralski (NCZ) silicon annealed at 650 °C has been investigated. The evolution of N‐N pairs and NNO complexes has been semi‐quantitatively elucidated based on the diffusion‐limited reaction theory. It is pointed out that the N‐O pairs and NNO complexes react with the interstitial atoms, leading to NNOx (x ≥ 1) particles, which serve as the nuclei of oxygen precipitate. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Plastic deformation of silicon between 20 °C and 425 °C
Authors: Rabier J. , Renault P. O. , Eyidi D. , Demenet J. L. , Chen J. , Couvy H. , Wang L.
Published: May 2007

Mechanical data have been obtained on silicon single crystal under hydrostatic pressure between room temperature and 450 °C. This temperature domain corresponds to the regime where perfect dislocations control plastic deformation. This was achieved using a D‐DIA apparatus in the synchrotron beam of NSLS. Stress strain curves were deduced from X Ray diffraction and sample imaging under 5 GPa and a strain rate of 2.5 10–5 s–1. Yield stresses as a function of temperature exhibit different temperature dependence when deformation is controlled by perfect dislocations. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Chlorotrityl Chloride (CTC) Resin as a Reusable Carboxyl Protecting Group
Authors: García‐Martín Fayna , Bayó‐Puxan Núria , Cruz Luis J. , Bohling James C. , Albericio Fernando
Published: May 2007

Chlorotrityl Chloride (CTC) resin is one of the most useful resins for the solid‐phase synthesis of C‐terminal acid peptides. CTC resin can be used for the preparation of both protected and unprotected peptides. Herein, the use of CTC resin as a reusable mild protecting group of carboxylic acids is introduced. Temporary protection of carboxylic acids in solution is not a straightforward process, but the use of CTC resin is shown to be an alternative to classic solution procedures. Regeneration of the CTC resin after cleavage of the target compounds is feasible, which allows the reuse of the resin. Applications described herein encompass the preparation of noncommercial amino acids as well as complex dipeptides.
New antidepressants and the biology of depression
Authors: Leonard B. E.
Published: May 2007

This review begins by summarizing the evidence to show how the neuroendocrine and central neurotransmitter systems are interconnected in the adaptation of the mammal to environmental stress. Depression may result from a failure of such systems to adapt and evidence is provided showing that these systems are abnormal in the depressed patient. The function of antidepressant therapy, whether by drug or ECT, is largely to normalize noradrenergic and serotonergic receptor responsiveness. There is little convincing evidence to suggest that the qualitative effects of any of the antidepressants differ following their chronic administration despite their well‐established differences after acute administration to animals. The superiority of the new antidepressants lies almost entirely in their greater safety.
The doctor as a placebo
Authors: Clyne M. B.
Published: May 2007

‘Placebo’ and ‘placebo effect’ have different meanings in pharmacology and in clinical practice. The action of almost all drugs, especially of psychopharmaca, has a placebo component. Drug effects are altered by relationship and emotional concomitants, especially by the doctor, one of the most powerful ‘drugs’. Human responses to psychopharmaca are often inexplicably variable, and cannot be understood without taking into account the effect of the doctor and of the relationship between the doctor and the patient. It is therefore of the utmost importance to study the pharmacology of the drug ‘doctor’ in therapeutics, both in isolation and in its relationship to medicaments. Drugs, ie chemical compounds administered for therapeutic purposes, and not only psychopharmaca, are also able to affect relationships and emotions. These effects, often disregarded, should also be studied, not least because the alteration of relationship (eg the doctor—patient relationship) and emotions will secondarily influence the pharmacological action of the pharmaca.
The stress and strain of pain
Authors: Haward Lionel R. C.
Published: May 2007

The definition of stress is briefly discussed, and a plea is made for scientific consistency in terminology. Operational definitions of stress and strain are provided. The physical and psychological components of pain stress are then examined, and pain stress is held to comprise the complete process from onset of tissue damage or other noxious condition to the experience of pain itself. The pain‐gate theory as an explanation for the psychological anomalies of pain is briefly described. A distinction is then made between conditions of acute and chronic pain: the former presents with a pattern of anxiety, while the latter matches a psychiatric depressive condition. Chronic pain and depression are inextricably interwoven and interactive, and exist as a discrete and identifiable syndrome. Psychological pain management techniques have a minimal part to play in the treatment of acute pain, but become of increasing relevance and importance as the duration of the pain increases. Various types of psychological intervention for pain relief are listed, and it is suggested that the psychologist's most useful role is that of detailed comprehensive appraisal of the pain patient and the planning of a programme of psychological treatment specific to the individual concerned. Such therapy to reduce pain stress and eliminate pain strain can then be carried out by appropriate trained health care workers under medical supervision.
Stress factors in dermatology
Authors: Walton Robert G.
Published: May 2007

The changes occurring in the skin as a result of stress are initially physiological and temporary. However, if repeated frequently enough, they eventually become permanent and so pathological. It has been estimated that, in 34 per cent of cases of dermatological disease, stress was the precipitating factor.

Dermatological stress disorders can be classified into the following: exclusively emotional; partly organic and partly psychological; emotional predisposing, perpetuating or precipitating factors; and unsightly diseases affecting the psyche.

Pruritus is an important factor in many diseases, since it produces the itch‐scratch vicious cycle. No matter what the cause of the itch, the current emotional state, including anxiety, tension and fear, are factors which influence it.
Occupational stress among word process operators
Authors: Cooper Cary L. , Cox Anna
Published: May 2007

This study assessed the link between work stress and mental health/job satisfaction among a group of 166 word process operators and copy typists. It was found that word process operators perceived more aspects of their job as stressful, and were more job dissatisfied, than copy typist—secretaries. More importantly, ‘lack of role clarity’ was the single most significant predictor of mental ill‐health and job dissatisfaction among word process operators, together with ‘limited career prospects’. The implications of these and other findings are discussed.
Endocrine associations with mood and sleep
Authors: Jenner D. A. , Anderson A. W. , Harrison G. A.
Published: May 2007

In a sample of 74 men and 82 women residing in a suburban area of Oxford, UK, 24‐hour urine samples were collected over a period during which they were engaged in normal daily activities. Questionnaires were used to obtain subjective mood ratings and information on sleep latency, quality and duration. Interrelationships between mood and sleep variables and urinary excretion of catecholamines and corticosteroids were investigated.

A checklist of 57 mood adjectives based on previous checklists developed by MacKay et al. and McNair and Lorr was used. Predefined factors derived by the previous authors showed some association with features of sleep but little association with hormone excretion. Factors derived from the actual patterns of responses of the present population showed stronger associations with hormone excretion.
Stress in aircrew
Authors: Haward L. R. C.
Published: May 2007

Professional aircrew, pilots especially, are subjected to a cumulative complexity of stresses unique in occupational medicine. The assessment of strain and of ‘stress thresholds’ and the prediction of breakdown under stress by psychophysiological techniques are areas of contemporary aeromedical research.

Stress management techniques have been applied to aircrew members, both prophylactically and as therapy, with some measure of success. Existing techniques can provide a practical and useful screening device by which the more stress‐vulnerable members of aircrew can be detected.
Stress and obesity
Authors: Rand Colleen S. W. , Kuldau John M.
Published: May 2007

In this paper, we briefly discuss certain medical‐psychiatric implications of obesity. The stressful effects of being obese are then presented. Next, we focus on stress in its relationship to overeating, obesity and eating disorders. Then we discuss the stress associated with dieting and maintenance of weight loss. Finally, we present a clinical framework for assessing the roles of obesity, weight concerns and stress.
Menstrual stress
Authors: Dalton Katharina
Published: May 2007

Menstruation and stress are closely related. Stress can cause alterations of menstruation, while alterations of menstruation can result in stress. The normal menstrual pattern shows wide variations in cycle length from 21 to 36 days and the duration of menstrual flow may last from two to eight days, and there are variations both within and between individuals. The effect of the same stress on the menstrual pattern may be different and opposite in individuals, but the same response tends to continue throughout the menstrual lifespan. Menstrual synchrony can occur among those living closely together, while the male may influence the length of the woman's menstrual cycle depending on the frequency of contact.

Formerly, many menstrual disorders for which no structural abnormality could be detected were regarded as being of psychological origin. With increasing knowledge of hormonal interactions, neurohormones, receptors and binding mechanisms, and with improved investigative techniques, such as radioimmunoassays, ultrasonic pelvic scan and laparoscopy, today many hormone abnormalities have been uncovered to account for menstrual disorders. Thus premenstrual syndrome is now known to be caused by a deficiency of progesterone, spasmodic dysmenorrhoea by an excess of prostaglandin F2 alpha and menopausal symptoms by oestrogen deficiency. These hormonal abnormalities can be corrected by appropriate therapy and should therefore now be recognized as coming within the ambiance of gynaecological endocrinologists.