bluuebunny/crossref_metadata_2025 huggingface dataset:
Managerial Efficiency and Human Capital Information: Linkages with the Voluntary Disclosure of Labour Costs
Authors: LAJILI KAOUTHAR
Published: January 2008

This research paper examines the information content and managerial incentives for labour cost voluntary disclosures for a sample of United States publicly traded companies. We focus on labour productivity and managerial efficiency in labour usage and argue that these human capital indicators could provide valuable information to capital market participants seeking human resource‐type of performance measures and signals. Labour productivity and efficiency indicators are estimated following a production function approach and are included in logistic regressions to help explain and predict labour cost voluntary disclosure decisions. We find that labour productivity and managerial efficiency in labour use indicators are generally different between disclosing and non‐disclosing firms, and that proprietary information costs and political cost proxies are significantly related to labour costs voluntary disclosure, consistent with previous literature. These empirical results corroborate the ‘proprietary information’ hypothesis of voluntary disclosure where the strategic costs of disclosure outweigh the signaling benefit from disclosing human capital information.
A NOTE ON THE EXPIRATION DAY PRICE EFFECT IN THE AUSTRALIAN 90 DAY BANK ACCEPTED BILLS MARKET
Authors: Oliver B. , Tahir M.
Published: January 2008

This paper investigates the impact on the price volatility of Australian 90 day Bank Accepted Bills (BABs) when the futures contracts written on BABs expire. Using the absolute value of log price changes as a measure of volatility, and appropriate non‐parametric tests, the analysis does not detect any expiration day price effect, nor reversal in volatility between expiration Fridays and the following Mondays for the period 1 November 1979 to 1 November 1993. These findings are consistent with the results of those overseas studies which do not find evidence for expiration day effects.
Research Agendas for the New Millennium: Celebrating Methodological Diversity
Authors: Broadbent Jane
Published: January 2008

As the old century comes to an end and the new one begins, we can see a tendency to consider where we are as individuals, communities and nations. This is undertaken by both looking back at where we have come from and reflecting on where we might go. Whilst in some ways the turn of the century is a completely arbitrary boundary to use for such a purpose, the change seems to almost compel us to such reflection. In doing this we seek to make sense of what has passed and make plans for the future. In essence we seek to order our lives by labelling time and sorting our experiences. Historians demonstrate that the naming of time has always been commonplace, if also contested, perhaps as a way of making sense of the complexity of everyday life (Corfield 1996). As accountants of course we deal with issues of periodisation all the time. It forms the fundamental foundation of our calculations and is rarely cause for question. It is perhaps unsurprising that accountants are amongst those who are seeking to contemplate tire stale of their world as the new millennium approaches and this is one such attempt. The outcome of such reflections is manifest each year in the form of New Year Resolutions. The aim of this short paper is to argue the case for a New Millennium Resolution for the academic accounting community. That resolution is that we make active efforts to both encourage and value a broad range of approaches to research.
The Managerial Roles of Accounting: A Value‐Adding Perspective for the New Millennium
Authors: Dunk Alan
Published: January 2008

Considerable international attention is now focused on management accounting to deliver value‐adding services that facilitate effective decision making against the backdrop of complex and often unpredictable global structural changes. A review is made of a number of potential opportunities for accounting to contribute to organisational performance, together with a discussion of some possible shortcomings. One conclusion arising from this analysis is that management accounting must become organisationally proactive to ensure its value‐adding role.
The Professional Accounting Body in the 21st Century: The Global Franchise
Authors: Velayutham Sivakumar
Published: January 2008

This paper seeks to identify and describe the shape of the professional accounting body in the new millennium. It is argued that the professional accounting body is at the brink of major changes at the turn of the century, due to its traditional role of self‐regulation being threatened by other institutions within the accounting domain. The paper identifies the professional accounting body in the twenty‐first century to be similar to that of a franchise. This, it is highlighted, would lead to the emergence of the global franchise.
Trust in Financial Reporting
Authors: Whittington Geoffrey
Published: January 2008

Trust is an essential ingredient in facilitating financial transactions. The financial reporting process helps to create trust, but it, in turn, has to be trusted. Auditing and professional standards have been the traditional means by which trust in financial reporting has been fostered. Recently, these institutions have been put under great pressure by changes in the size and scope of financial markets. The consequence is likely to be a continuing change in the nature of trust and the means by which it is supported. In the future, personal trust is likely to be substituted increasingly by trust in systems supported by regulatory bodies. This does not mean that trust is no longer important, but rather that the form which it takes has changed. The importance of trust needs to be recognised by those engaged in shaping the future of financial reporting, if they are to meet the needs of users of financial information.
An Investigation of the Significance of Mandated Changes in Goodwill Amortisation Policy in Australia
Authors: Day Ron , Hartnett Neil
Published: January 2008

This paper examines the controversy surrounding the use of the Inverted‐Sum‐Of‐Years‐Digits (ISOYD) method of goodwill amortisation and events leading to its banning by the Australian accounting regulatory bodies. Companies using the method claimed that a prohibition would reduce their share price and international competitiveness. On the other hand, efficient capital market proponents argued that the amortisation method was irrelevant to the economic position of a firm in the absence of any cash flow effects. This paper discusses these conflicting views and investigates possible motives for the choice of goodwill amortisation method through a cross‐company analysis of key characteristics. In addition, sharemarket reaction to key events leading to the change of policy was examined using conventional event‐study methodology. The cross‐company analysis revealed significant differences in the goodwill characteristics between ISOYD companies and non‐ISOYD companies which may have motivated their choice. The result of the event‐study found that no significant abnormal return could be unequivocally attributed to any of the key events or announcements.
Environmental Accounting in the New Zealand Contracting Industry: Comments on the Use of Mail Survey Method — A Rejoinder
Authors: Guilding Chris
Published: January 2008

Many of the survey design issues raised by Tung (2000) are revisited in the context of Guilding and Kirman's (1998) study. While several practical issues are raised, underlying this rejoinder is the message that when conducting questionnaire survey research, issues can arise that require the researcher to exercise a degree of subjective judgement. While the researcher should always attempt to observe the types of practice noted by Tung, the application of these practices can be compromised when one turns to the reality of operationalisalion in the context of a particular research question(s) and a particular sample.
Classification of Foreign Operations For Financial Reporting
Authors: Laswad Fawzi , Roush Melvin
Published: January 2008

Financial reporting standards on foreign currency translation in many countries such as New Zealand, US, Australia, and Canada and the international standard issued by the International Accounting Standards Committee require the classification of foreign operations for translation purposes into two mutually exclusive types: integrated or independent. This classification determines the translation method. In judging whether a foreign operation is either integrated or independent, the accounting standard requires the evaluation of five qualitative factors. The standard neither describes the judgement process nor identifies the relative importance of the determining factors. It has been asserted that this lack of clarity may yield dissimilar results for firms whose circumstances are similar and consequently may reduce the comparability of financial statements across firms. Using a repeated measures design, this paper examines the judgement of preparers of financial statements (financial controllers) in determining the designation of foreign operations for translation purposes. The results indicate that the relative importance of the determining factors is about equal. No support is found for the assertion that the use of qualitative factors in accounting standards results in dissimilar judgements (lack of consensus) across respondents. Further, the results show that the subjects demonstrated consistency and self‐insight in their judgements. The results also indicate that the judgements of respondents are not biased toward either classification of foreign operation. This suggests that the observed bias may be motivated by economic factors rather than the outcome of using the qualitative cues in the accounting standard. When the respondents were debriefed, several of them identified ‘managerial independence’ as another determining factor that has not been included in the standard.
Financial Leverage and Firm Response to Poor Performance
Authors: Whiting Rosalind , Gilkison Simon
Published: January 2008

This study tests the relationship between financial leverage and a firm's operational and financial short term responses to poor performance, based on Jensen's (1989) argument that higher predistress leverage increases a firm's incentive to respond more quickly to poor performance. This research is conducted on a sample of 45 poorly performing New Zealand firms between 1985 and 1994. The results indicate that higher leverage increases the probability of firms taking action in the short term. In particular, the evidence suggests that the probability of asset sales is positively associated with long‐term leverage, in addition to its relationship with the firm's stock return. Increased probability of management replacement is related to higher levels of short‐term leverage and surprisingly, the probability of dividend cuts decrease with higher levels of total and short‐term leverage. Poorly performing firms with higher leverage also appear to cut asset levels and dividends more aggressively than those with lower leverage levels.
Style Analysis: Is it Useful in Analysing New Zealand Managed Trusts?
Authors: Gronewoller Paul L. , McLeod Janet , Rose Lawrence C.
Published: January 2008

This study evaluates the practicability of style analysis in evaluating the risk‐adjusted performance of New Zealand's retail equity trusts. The size of the New Zealand market and the short history of data available generate doubts concerning the usefulness of style analysis under these conditions. Style analysis provides useful insight when applied to the New Zealand retail equity unit trust sector. Two prevalent styles are identified, a large cap style and a mid‐cap‐value/small cap style. Little variation in style was detected for the group of trusts that tracked the large‐cap equity index but substantial variation was indicated in relative performance versus a passive investment in their style benchmarks. Significant variation was detected, both in terms of style and relative performance of trusts that tracked a mid‐cap‐value/small‐cap index. A small number of New Zealand equity managers were able to maintain a consistent style, while meeting or beating the performance of their style benchmarks.
An Empirical Investigation of the Cross‐Industry Variation in Mean Reversion of Australian Stock Betas
Authors: BROOKS ROBERT , FAFF ROBERT , JOSEV TOM
Published: January 2008

In this paper we empirically investigate the tendency for beta risk to mean‐revert across industries. Using a sample of Australian stocks over the ten‐year period 1989 to 1998, our key results are as follows. We generally observe evidence of a mean reversion tendency — in particular, this seems most appropriate for the Gold, Energy, Finance and Consumer industry groupings. Moreover, there is some evidence that the mean reversion of beta is different across industries. Furthermore, we see that the maximum mean reversion beta occurs for the Gold industry — a value of approximately 1.4 (1.6) for the OLS (Scholes‐Williams) beta analysis. On the other hand, the minimum mean reversion beta based on the ‘All Stocks’ OLS analysis occurs for Miscellaneous Industries with a value of 0.4, while a similar minimum mean reversion beta based on the Scholes‐Williams analysis occurs for the Consumer industry grouping.
An Analysis of Corporate Lobbying on Australia's ED 49, Accounting for Identifiable Intangible Assets
Authors: Gerhardy Peter , Wyatt Lisa
Published: January 2008

In this paper content analysis is used to examine the lobbying positions of publicly listed companies making submissions on ED 49, Accounting for Identifiable Intangible Assets. A number of content analysis measures are used in an attempt to gain additional insights into the strength of lobbying positions held. The influence of debt contracting and political costs variables upon lobbying position on capitalisation and amortisation of identifiable intangible assets is investigated. Significant relationships are found with the explanatory variables interest coverage, company size, effective tax rate and membership of a politically sensitive industry. These relationships are most consistently observed when lobbying position is measured using more basic content analysis techniques, such as sentence counts and counting the number of supporting arguments presented in submissions. Use of apparently more sophisticated techniques of content analysis fail to perform as well, possibly due to the introduction of greater subjectivity to the process.
An Investigation of the Relationship between Stated Fund Management Policy and Market Timing Ability
Authors: Benson Karen , Pope Peter , Faff Robert
Published: January 2008

This paper examines the market timing ability of a sample of 62 Australian International equity funds using the returns‐based approach of Henriksson and Merton (1981) (H&M) and Treynor and Mazuy (1966) (T&M). Specifically, the primary focus is to investigate whether market timing ability bears any relationship to the stated fund allocation policy. Generally, the results indicate that fund managers do not successfully time the market. We also find that there is no relationship between the manager's stated level of activity on allocation and their market timing abilities as calculated using the H&M and T&M models. Managers are not successfully implementing their stated policies. These results are consistent with an irrelevance of perceived management style to fund policies and hence performance. Furthermore, it is indicative that fund managers are not successfully targeting particular classes of risk averse investors.
The Influence of Organisational Commitment on the Use of Financial Measures for Performance Evaluation
Authors: Lau Chong M. , Ng Jefferson
Published: January 2008

Prior studies on the interactive effects of performance evaluative style and budgetary participation on managers' budgetary performance have overlooked several important issues. First, the moderating effects of organisational commitment have largely been overlooked. Since managers, who are highly committed to their organisations, are likely to pursue their organizations' goals much more intensely than managers who are not committed to their organisations, the effects of performance evaluative style and budgetary participation on the budgetary performance of these two groups of managers are likely to differ. Second, prior studies in this research area have concentrated mainly on the manufacturing sector. The services sectors have received relatively little attention. Third, differences between privately owned service organisations and publicly funded service organisations and their effects on performance have also not been considered. To address these gaps in the literature, this study investigates the three‐way interaction between reliance on financial measures for performance evaluation, budgetary participation and organisational commitment affecting budgetary performance in the health services sector. Based on a sample of 170 managers, the results indicate that highly committed managers react very differently to reliance on financial measures for performance evaluation and budgetary participation from lowly committed managers. Differences were also found between managers from the privately funded service organisations and those from the publicly funded service organisations.
THE RESILIE
Authors: Williams Roger , Dale Barrie , Van der Wiele Ton
Published: January 2008

Like the reports of Mark Twain's death, the demise of total quality has been much exaggerated. Periodic changes of direction and drivers have given it new life and impetus during the time it has been popularized by western organizations. Each renewal brings with it a new set of measures to define and manage quality, each of which adds to a cumulative embedding of total quality in the way a business operates.
Finding and evaluating sources of evidence: nicotine replacement therapy as a case study
Authors: Booth Andrew
Published: January 2008

Although in many decision‐making contexts it may be a problem actually to find any evidence there are already a number of topics where the challenge is presented by the bewildering array of sources and formats in which published findings are made available. By focusing on just one of these areas, nicotine replacement therapy, and by exploring characteristics such as usability and authoritativeness with a group of health professionals, the author attempts to highlight some important issues in both finding and evaluating the evidence. The results of this opportunistic preliminary investigation are presented together with some suggestions for further research and implications for health information professionals in their quest for evidence.
National survey of UK clinical guidelines for the management of coronary heart disease, lung and breast cancer, asthma and depression
Authors: Cluzeau Françoise , Littlejohns Peter , Grimshaw Jeremy , Feder Gene
Published: January 2008

There is anecdotal evidence of a plethora of guidelines developed throughout the NHS. A national survey was carried out between March and June 1995 to identify the number of clinical guidelines produced in the UK in the clinical areas of coronary heart disease, asthma, breast cancer, lung cancer and depression. The response to the survey ranged from 95% (interest groups) to 10% (Ministry of Defence and prison hospitals). Four hundred and seventy two guidelines were identified in the survey. Most had been produced locally, only 21 guidelines were classified as national. Results confirm that there is a proliferation of guidelines in most parts of the UK. The survey illustrates the difficulties involved in conducting a UK survey of this kind, and highlights the need for national guideline coordination.
The Effect of Institutional Ownership on Board and Audit Committee Composition
Authors: Feldmann Dorothy A. , Schwarzkopf David L
Published: January 2008

We investigate the relationship between institutional shareholdings and the firm's corporate governance by looking at changes in the composition of the board of directors and audit committee while institutional ownership increases over time. Our comparison of 74 firms showing increased institutional ownership with a matched control group of 62 firms finds that increased institutional ownership is positively associated with a higher proportion of outsiders on the board and with audit committee and board members who are less entrenched. These factors are widely regarded as signs of a strengthened system of corporate governance and control, underscoring the important role that institutional ownership may play in the firm's corporate governance structure.
Is Earnings Management Affected by Human Development and Economic Freedom?
Authors: Riahi‐Belkaoui Ahmed
Published: January 2008

Based on the idea that insiders (i.e., managers and controlling shareholders) engage in earnings management to mask their diversion and rent seeking activities from outsiders, this paper presents international evidence supporting both a “diversion hypothesis” where earnings management is decreasing in economic freedom, and a “penalty hypothesis” where earnings management is increasing in human development.
Earnings Opacity and the Productivity of Nations
Authors: Riahi‐Belkaoui Ahmed
Published: January 2008

Output per worker varies significantly from one country to another. Why? Our analysis shows that differences in earnings opacity are important sources of this variation. Earnings opacity is a measure that reflects how little information there is in a firm's earnings number about its true, but unobservable, economic performance. According to our results, a high‐productivity country has the accounting quality associated with low earnings opacity. Results further suggest that the quality of accounting in general, and low earnings opacity in particular helps a country by stimulating the accumulation of human and physical capital and by raising its total factor productivity.
Leveling the informational Playing Field
Authors: Barron Orie E. , Byard Donal , Enis Charles R.
Published: January 2008

This study uses experimental data to compare the information generated by professional and nonprofessional investors when both groups receive access to the same financial disclosures. We also manipulate the disclosure level for both subject groups. Using the method developed by Barron, Kim, Lim and Stevens (1998), we then analyze the information contained in stock price forecasts that were made by the experimental subjects. Professionals on average inferred more information than nonprofessionals. The higher level of disclosure did not affect the information possessed by the professional investors. However, we find that a higher level of disclosure is associated with more private information being produced (or inferred) by nonprofessional investors. As a result, these subjects realized a significant improvement in the accuracy of their mean forecasts relative to their individual forecasts. This finding suggests that the enhanced capacity of firms to widely disclose information to all market participants via the Internet, together with the SEC's new “Fair Disclosure (FD)” regulation, has the potential to produce a significant increase in privately inferred information for on‐line nonprofessionals, potentially resulting in the aggregation of more diverse information into share prices.
Greenmail Share Repurchases and Alternative Corporate Performance Measures
Authors: Manry David , Stangeland David
Published: January 2008

This research uses accounting information to supplement abnormal returns evidence in order to gauge the performance of greenmailed firms. Our results support the management entrenchment hypothesis; target firm earnings are poor relative to industry in the years surrounding the greenmail event, and earnings do not significantly improve as would be expected under the shareholders' interest hypothesis. This result holds after adjusting for greenmail premia net of tax effects. Evidence on investment spending suggests firms that pay greenmail differ substantially from their industries, but in a negative direction. In contrast, the industry‐adjusted earnings of non‐greenmail repurchasing firms are significantly greater than the earnings of greenmailed firms. Together, these results are consistent with the contention that greenmailed firms are not managed in shareholders' interests; they underperform their industry, the poor operating results are not attributable to higher investment outlays associated with a long‐term strategic focus, and performance does not improve. This is consistent with observed negative abnormal returns being attributable to both a lost takeover premium and a lost opportunity for improved corporate performance.
The MVA‐EVA Relationship: Separation of Market Driven Versus Firm Driven Effects
Authors: Zaima Janis K. , Turetsky Howard F. , Cochran Bruce
Published: January 2008

Studies that examine the relationship of economic value added (EVA) to market value did not isolate the EVA effect in conjunction with controlling for the economic effect of the market. Since the EVA metric is viewed as value‐added apart from the market, operational managers will benefit from a procedure that separates the market driven versus firm driven (EVA) effects. Our paper examines the effects of the economy and EVA on MVA. The results indicate that EVA and GDP significantly affect MVA. Furthermore, the MVA‐EVA relationship shows a systematic bias between the largest MVA firms and the smallest MVA firms. Overall, our study provides implications for corporate executives utilizing EVA to evaluate managerial performance linked to MVA.
Change in Bid‐Ask Spread Around Earnings Announcements of U.S. — Listed Foreign Firms
Authors: Chan Kam C. , Li Chunyan
Published: January 2008

Prior studies find increased bid‐ask spread around earnings announcements of U.S. firms. These findings show that increased adverse selection cost is the dominant factor affecting bid‐ask spread. Using a sample of foreign firms that are cross‐listed on Nasdaq as American Depositary Receipts, we find that there is significant decrease in bid‐ask spread around earnings announcements of these foreign firms. The results suggest that increased trading volume is the dominant factor affecting the bid‐ask spread of American Depositary Receipts around earnings announcements.
Acute kidney injury in the rat causes cardiac remodelling and increases angiotensin‐converting enzyme 2 expression
Authors: Burchill L. , Velkoska E. , Dean R. G. , Lew R. A. , Smith A. I. , Levidiotis V. , Burrell L. M.
Published: January 2008

Patients with kidney failure are at high risk of a cardiac death and frequently develop left ventricular hypertrophy (LVH). The mechanisms involved in the cardiac structural changes that occur in kidney failure are yet to be fully delineated. Angiotensin‐converting enzyme (ACE) 2 is a newly described enzyme that is expressed in the heart and plays an important role in cardiac function. This study assessed whether ACE2 plays a role in the cardiac remodelling that occurs in experimental acute kidney injury (AKI). Sprague–Dawley rats had sham (control) or subtotal nephrectomy surgery (STNx). Control rats received vehicle (n= 10), and STNx rats received the ACE inhibitor (ACEi) ramipril, 1 mg kg−1 day−1 (n= 15) or vehicle (n= 13) orally for 10 days after surgery. Rats with AKI had polyuria (P < 0.001), proteinuria (P < 0.001) and hypertension (P < 0.001). Cardiac structural changes were present and characterized by LVH (P < 0.001), fibrosis (P < 0.001) and increased cardiac brain natriuretic peptide (BNP) mRNA (P < 0.01). These changes occurred in association with a significant increase in cardiac ACE2 gene expression (P < 0.01) and ACE2 activity (P < 0.05). Ramipril decreased blood pressure (P < 0.001), LVH (P < 0.001), fibrosis (P < 0.01) and BNP mRNA (P < 0.01). These changes occurred in association with inhibition of cardiac ACE (P < 0.05) and a reduction in cardiac ACE2 activity (P < 0.01). These data suggest that AKI, even at 10 days, promotes cardiac injury that is characterized by hypertrophy, fibrosis and increased cardiac ACE2. Angiotensin‐converting enzyme 2, by promoting the production of the antifibrotic peptide angiotensin(1–7), may have a cardioprotective role in AKI, particularly since amelioration of adverse cardiac effects with ACE inhibition was associated with normalization of cardiac ACE2 activity.
Population Diversity of Yeasts and Lactic Acid Bacteria in Pig Feed Fermented with Whey, Wet Wheat Distillers' Grains, or Water at Different Temperatures
Authors: Olstorpe Matilda , Lyberg Karin , Lindberg Jan Erik , Schnürer Johan , Passoth Volkmar
Published: January 2008

The diversity of populations of yeast and lactic acid bacteria (LAB) in pig feeds fermented at 10, 15, or 20°C was characterized by rRNA gene sequencing of isolates. The feeds consisted of a cereal grain mix blended with wet wheat distillers' grains (WWDG feed), whey (W feed), or tap water (WAT feed). Fermentation proceeded for 5 days without disturbance, followed by 14 days of daily simulated feed outtakes, in which 80% of the contents were replaced with fresh feed mixtures. In WWDG feed,
Pichia galeiformis
became the dominant yeast species, independent of the fermentation temperature and feed change. The LAB population was dominated by
Pediococcus pentosaceus
at the start of the fermentation period. After 3 days, the
Lactobacillus plantarum
population started to increase in feeds at all temperatures. The diversity of LAB increased after the addition of fresh feed components. In W feed,
Kluyveromyces marxianus
dominated, but after the feed change, the population diversity increased. With increasing fermentation temperatures, there was a shift toward
Pichia membranifaciens
as the dominant species.
L
.
plantarum
was the most prevalent LAB in W feed. The WAT feed had a diverse microbial flora, and the yeast population changed throughout the whole fermentation period.
Pichia anomala
was the most prevalent yeast species, with increasing occurrence at higher fermentation temperatures.
Pediococcus pentosaceus
was the most prevalent LAB, but after the feed change,
L. plantarum
started to proliferate. The present study demonstrates that the species composition in fermented pig feed may vary considerably, even if viable cell counts indicate stable microbial populations.
CcpA Regulates Central Metabolism and Virulence Gene Expression in
Streptococcus mutans
Authors: Abranches Jacqueline , Nascimento Marcelle M. , Zeng Lin , Browngardt Christopher M. , Wen Zezhang T. , Rivera Mercedes F. , Burne Robert A.
Published: January 2008

CcpA globally regulates transcription in response to carbohydrate availability in many gram-positive bacteria, but its role in
Streptococcus mutans
remains enigmatic. Using the fructan hydrolase (
fruA
) gene of
S. mutans
as a model, we demonstrated that CcpA plays a direct role in carbon catabolite repression (CCR). Subsequently, the expression of 170 genes was shown to be differently expressed (≥2-fold) in glucose-grown wild-type (UA159) and CcpA-deficient (TW1) strains (
P
≤ 0.001). However, there were differences in expression of only 96 genes between UA159 and TW1 when cells were cultivated with the poorly repressing substrate galactose. Interestingly, 90 genes were expressed differently in wild-type
S. mutans
when glucose- and galactose-grown cells were compared, but the expression of 515 genes was altered in the CcpA-deficient strain in a similar comparison. Overall, our results supported the hypothesis that CcpA has a major role in CCR and regulation of gene expression but revealed that in
S. mutans
there is a substantial CcpA-independent network that regulates gene expression in response to the carbohydrate source. Based on the genetic studies, biochemical and physiological experiments demonstrated that loss of CcpA impacts the ability of
S. mutans
to transport and grow on selected sugars. Also, the CcpA-deficient strain displayed an enhanced capacity to produce acid from intracellular stores of polysaccharides, could grow faster at pH 5.5, and could acidify the environment more rapidly and to a greater extent than the parental strain. Thus, CcpA directly modulates the pathogenic potential of
S. mutans
through global control of gene expression.
Regulation of Expression and Secretion of NleH, a New Non-Locus of Enterocyte Effacement-Encoded Effector in
Citrobacter rodentium
Authors: García-Angulo Víctor A. , Deng Wanyin , Thomas Nikhil A. , Finlay B. Brett , Puente Jose L.
Published: January 2008

Together with enterohemorrhagic
Escherichia coli
and enteropathogenic
Escherichia coli
,
Citrobacter rodentium
is a member of the attaching-and-effacing (A/E) family of bacterial pathogens. A/E pathogens use a type III secretion system (T3SS) to translocate an assortment of effector proteins, encoded both within and outside the locus of enterocyte effacement (LEE), into the colonized host cell, leading to the formation of A/E lesions and disease. Here we report the identification and characterization of a new non-LEE encoded effector, NleH, in
C. rodentium
. NleH is conserved among A/E pathogens and shares identity with OspG, a type III secreted effector protein in
Shigella flexneri
. Downstream of
nleH
, genes encoding homologues of the non-LEE-encoded effectors EspJ and NleG/NleI are found. NleH secretion and translocation into Caco-2 cells requires a functional T3SS and signals located at its amino-terminal domain. Transcription of
nleH
is not significantly reduced in mutants lacking the LEE-encoded regulators Ler and GrlA; however, NleH protein levels are highly reduced in these strains, as well as in
escN
and
cesT
mutants. Inactivation of Lon, but not of ClpP, protease restores NleH levels even in the absence of CesT. Our results indicate that the efficient engagement of NleH in active secretion is needed for its stability, thus establishing a posttranslational regulatory mechanism that coregulates NleH levels with the expression of LEE-encoded proteins. A
C. rodentium nleH
mutant shows a moderate defect during the colonization of C57BL/6 mice at early stages of infection.
Culture of
Campylobacter jejuni
with Sodium Deoxycholate Induces Virulence Gene Expression
Authors: Malik-Kale Preeti , Parker Craig T. , Konkel Michael E.
Published: January 2008

Campylobacter jejuni
, a spiral-shaped gram-negative bacterium, is a leading bacterial cause of human food-borne illness. Acute disease is associated with
C. jejuni
invasion of the intestinal epithelium. Further, maximal host cell invasion requires the secretion of proteins termed
Campylobacter
invasion antigens (Cia). As bile acids are known to alter the pathogenic behavior of other gastrointestinal pathogens, we hypothesized that the virulence potential of
Campylobacter
may be triggered by the bile acid deoxycholate (DOC). In support of this hypothesis, culturing
C. jejuni
with a physiologically relevant concentration of DOC significantly altered the kinetics of cell invasion, as shown by gentamicin protection assays. In contrast to
C. jejuni
harvested from Mueller-Hinton (MH) agar plates,
C. jejuni
harvested from MH agar plates supplemented with DOC secreted the Cia proteins, as judged by metabolic labeling experiments. DOC was also found to induce the expression of the
ciaB
gene, as determined by β-galactosidase reporter, real-time reverse transcription-PCR, and microarray analyses. Microarray analysis further revealed that DOC induced the expression of virulence genes (
ciaB, cmeABC, dccR
, and
tlyA
). In summary, we demonstrated that it is possible to enhance the pathogenic behavior of
C. jejuni
by modifying the culture conditions. These results provide a foundation for identifying genes expressed by
C. jejuni
in response to in vivo-like culture conditions.
RecO Is Essential for DNA Damage Repair in
Deinococcus radiodurans
Authors: Xu Guangzhi , Wang Liangyan , Chen Huan , Lu Huiming , Ying Nanjiao , Tian Bing , Hua Yuejin
Published: January 2008

Here we present direct evidence for the vital role of RecO in
Deinococcus radiodurans
's radioresistance. A
recO
null mutant was constructed using a deletion replacement method. The mutant exhibited a growth defect and extreme sensitivity to irradiation with gamma rays and UV light. These results suggest that DNA repair in this organism occurs mainly via the RecF pathway.
Polyhedral Dipalladaborane Chemistry. The Molecular Structure and Cluster Electron Count of [7,8-(PPh3)2-7,8-(μ-PPh2)-9,11-(OEt)2-nido-7,8-Pd2B9H8]
Authors: Bould Jonathan , Teat Simon J. , Kennedy John D.
Published: January 2008

[PdCl2(PPh3)2] and the [NHEt3]+ salt of [B10H10]2- in refluxing ethanol yield the dipalladaundecaborane cluster compound [7,8-(PPh3)2-7,8-(μ-PPh2)-9,11-(OC2H5)2-nido-7,8-Pd2B9H8] (1). An all-atom single-crystal synchrotron X-ray diffraction study shows a significant difference to four structurally characterised platinum congeners reported in the literature for which revised formulation is now necessary. The importance of taking into consideration the electron count in polyhedral boron-containing cluster systems in the course of their characterisation is emphasised.
The effect of girdling on starch accumulation in sour orange seedlings
Authors: Wallerstein I. , Goren R. , Monselise S. P.
Published: January 2008

Girdling of Citrus aurantium seedlings inhibited translocation of 14C-sucrose from leaves to roots, yet starch accumulation was observed in all parts of the seedlings including roots. Results indicated that girdling triggered starch accumulation in roots independent of carbohydrate transport from the leaves. The increase in starch content of leaves was accompanied by a decrease in the specific activity of the accumulated starch. Girdling also caused an increase in fresh weight in all parts of the seedling and a decrease in percentage dry weight of rootlets.
Electrogenic pumps in higher plant cells
Authors: Higinbotham N. , Anderson W. P.
Published: January 2008

The evidence for the existence of electrogenic pumps in higher plant cells is reviewed. A new theory of electrogenic transport is given. Which ion is pumped and the energy source for electrogenic transport are discussed.
Preparation of pycnidium-forming fungi for observation by scanning electron microscopy
Authors: Zeyen R. J. , Shearer B. L.
Published: January 2008

A procedure for the preparation of pycnidium-forming fungi, inside host tissues, for observation by scanning electron microscopy (SEM) has been developed, and consists of removal of mucilage from the pycnidium followed by fixation, embedding, and precision sectioning of pycnidia before final SEM preparation. The fungus tissues were fixed in glutaraldehyde and uranyl acetate. Tissues were prevented from collapsing by using glycerol substitution followed by air drying. The total procedure allows for direct comparisons, using the same sections, for light microscopy and SEM. Six species from the order Sphaeropsidales (Septoria avenae, S. avenae f, sp. triticea, S. nodorum, S. tritici, Darluca filum, and Phoma medicaginis) were used as experimental organisms; although only two species, S. avenae and S. tritici are pictorially represented.
Woody riparian vegetation of a Lake Superior tributary
Authors: Ericsson Kriste A. , Schimpf David J.
Published: January 2008

Woody vegetation along the lower 16 km of the Sucker River (a Lake Superior tributary in Minnesota) was surveyed as a precursor to leaf decomposition studies. Vegetation composition and its relation to the environment were assessed. The most abundant trees and shrubs were Alnus rugosa, Abies balsamea, Cornus stolonifera, and Fraxinus spp. The lower, steeper 10 km of the river was bordered by coniferous forest, above which was 3 km of Alnus thicket, then 3 km of mixed conifer–hardwoods along the flatter reaches farther inland. Alnus rugosa and Thuja occidentalis decreased dramatically in numbers a short distance from the river. Abies balsamea and Betula papyrifera showed the reverse trend. Polar ordinations revealed that riparian species composition was correlated with the gradient of the river but not with the aspect of the stream banks. The riparian vegetation was less distinct from the surrounding vegetation than is often the case with larger streams.
Culture characteristics and variation of Cronartium flaccidum isolates
Authors: Moricca S. , Ragazzi A.
Published: January 2008

Cultures of Cronartium flaccidum were established from aeciospores collected from Pinus halepensis and Pinus laricio growing at four Italian sites: one southern and one northern (north-central) site for each host species. The two southern and the two northern sites were also geographically separate. Colonies were incubated for 7 months and compared for growth rates, macroscopic and microscopic features of the colonies, presence or absence of sporulation, and spore type. Germ tubes exhibited negative geotropism and were light sensitive. Colonies from southern isolates generally remained white and fast growing throughout, whereas colonies from northern isolates tended to turn orange and become slow growing. The faster growing white colonies could be maintained in the same Petri dishes without undergoing morphological change for the entire incubation period, but the slow-growing orange colonies had to be transferred to fresh medium every month or they became covered with short, hyaline hyphae. Immature aeciospores, typical mature aeciospores, and teliospore-like bodies formed in culture. Spore ontogeny, capacity to be successfully subcultured, growth rate, and other evidence indicated the southern and north-central Italian isolates were distinct. The host species was not a factor in culture variation. The importance of the axenic technique in relation to rust disease research is discussed. Keywords: rust, in vitro growth, cultural variation, sporulation.
Urban geochemical mapping in the Campania region (Italy)
Authors: Cicchella D. , De Vivo B. , Lima A. , Albanese S. , Fedele L.
Published: January 2008

This work reviews the results of research conducted in the last five years on urban soils of the Campania region, southern Italy. Approximately 2000 topsoil samples were collected and analysed for 40 elements, among which are included the potentially harmful elements (PHE). The two most relevant objectives achieved were the determination of background levels for each element, using concentration–area (C–A) and separation–anomaly (S-A) algorithms, and the production of an extensive cartography, published in a series of geochemical atlases. The latter show that high PHE concentrations, exceeding many times the local natural backgrounds (especially Pb, Hg, Sb, Zn), are found in the most densely populated areas, often affected by heavy vehicular traffic and industrial activities. Many soil samples exceed the limits set for PHE by the Italian Ministry of the Environment in law DM 471/99 for residential land use. The geochemical maps can prove to be very useful both for scientists and professionals working towards the restoration of contaminated areas, as well as serving to refine the Italian environmental legislation to be more effective in local situations.
Complexation of platinum, palladium and rhodium with inorganic ligands in the environment
Authors: Colombo C. , Oates C.J. , Monhemius A.J. , Plant J.A.
Published: January 2008

Platinum (Pt), palladium (Pd) and rhodium (Rh) are emitted by vehicle exhaust catalysts (VECs) and their concentrations have increased significantly in various environmental compartments, including airborne particulate matter, soil, roadside dust, vegetation, rivers and oceanic environments, over the last two decades as the use of VECs has increased. However, data on the chemical speciation of the platinum-group elements (PGEs) and their bioavailabilities are limited. In this paper, the thermodynamic computer model, HSC, has been used to predict the interactions of Pt, Pd and Rh with different inorganic ligands and to estimate the thermodynamic stability of these species in the environment. Eh–pH diagrams for the PGEs in aqueous systems under ambient conditions (25°C and 1 bar) in the presence of Cl, N and S species have been prepared. The results indicate that Pt, Pd and Rh can form complexes with all of the inorganic ions studied, suggesting that they are capable of mobilizing the PGEs as aqueous complexes that can be transported easily in environmental and biological systems and that are able to enter the food chain. Hydroxide species can contribute to the transport of PGEs in oxidizing environments such as road-runoff waters, freshwater, seawater and soil solutions, whereas bisulphide complexes could transport Pt and Pd in reducing environments. Ammonia species appear to be significant under near-neutral to basic oxidizing conditions. Chloride species are likely to be important under oxidizing, acidic and saline environments such as seawater and road-runoff waters in snowmelt conditions. Mixed ammonia–chloride species may also contribute to the transport of Pt and Pd in highly saline solutions.
Anthropogenic and natural lead isotopes in Fe-hydroxides and Fe-sulphates in a watershed associated with arsenic-enriched groundwater, Maine, USA
Authors: Ayuso R.A. , Foley N.K.
Published: January 2008

A survey of the natural and anthropogenic sources of lead contributing to secondary minerals in sulphidic schists associated with arsenic-enriched groundwater in Coastal Maine shows that the most likely source is natural Pb, particularly from coexisting sulphide minerals. The secondary minerals also reflect notable contributions from anthropogenic Pb. The Pb isotopes establish pathways by which Pb, and by inference As, could have been transported from As-bearing minerals (arsenian pyrite, arsenopyrite, lollingite, orpiment, arsenic oxide and others), via sulphide oxidation or carbonation reactions into multiple generations of secondary minerals (goethite, hematite, jarosite, natrojarosite and others). Lead isotopic compositions of the sulphides and secondary minerals determined by thermal ionization mass spectrometry (
n
=53) range widely. Lead and As contents of the sulphides and secondary minerals overlap, and are generally positively correlated. Pyrite, the dominant sulphide in sulphidic schists associated with As-enriched groundwater in Coastal Maine, has values of
206
Pb/
204
Pb from 18.186 to 18.391,
207
Pb/
204
Pb from 15.617 to 15.657,
208
Pb/
204
Pb from 38.052 to 38.210,
206
Pb/
207
Pb from
c
. 1.1625 to 1.1760 and
208
Pb/
207
Pb from
c
. 2.4276 to 2.4394. Mixtures of Fe-hydroxide and oxide minerals (predominantly goethite and hematite) and secondary Fe-sulphate minerals (jarosite, natrojarosite, rozenite and melanterite) in the sulphidic schists have overlapping but generally higher values of
206
Pb/
204
Pb from 18.495 to 19.747 (one sample at 21.495),
207
Pb/
204
Pb from 15.595 to 15.722 (one sample at 15.839),
208
Pb/
204
Pb from 38.186 to 39.162,
206
Pb/
207
Pb from
c.
1.1860 to 1.2575 (one sample at 1.3855) and
208
Pb/
207
Pb from
c
. 2.4441 to 2.4865 than the sulphides. Sulphides from Zn-Pb metal mines are somewhat less radiogenic than sulphides from the schists. Other sulphides (mostly pyrite) associated with pegmatites and granitic rocks are heterogeneous and more radiogenic than the pyrite-rich sulphidic schists. Sulphides from other regional bedrock units also have heterogeneous isotope values. Lead isotopic compositions of the sulphides from the sulphidic schists and coexisting Fe-oxides and Fe-sulphates produced by weathering and alteration overlap, but the secondary minerals extend toward more radiogenic values that broadly indicate the addition of Pb from anthropogenic origin. As a component of Pb from extensively used arsenical pesticides may also be present in the secondary minerals, the range in Pb isotope values is consistent with multiple sources: natural Pb from the schists and anthropogenic Pb (industrial and possibly from agricultural activities). Contributions from past mining activities or from other bedrock sources are not implicated.