bluuebunny/crossref_metadata_2025 huggingface dataset:
Incorporating Sweeps and Ejections into Lagrangian Stochastic Models of Spore Trajectories Within Plant Canopy Turbulence: Modeled Contact Distributions Are Heavy-Tailed
Authors: Reynolds A. M.
Published: October 2012

The turbulent dispersal of fungal spores within plant canopies is very different from that within atmospheric boundary-layers and closely analogous to dispersal within turbulent mixing-layers. The process is dominated by the presence of large coherent flow structures, high-velocity downdrafts (sweeps) and updrafts (ejections), that punctuate otherwise quiescent flow. Turbulent dispersion within plant canopies is best predicted by Lagrangian stochastic (particle-tracking) models because other approaches (e.g., diffusion models and similarity theory) are either inappropriate or invalid. Nonetheless, attempts to construct such models have not been wholly successful. Accounting for sweeps and ejections has substantially worsened rather than improved model agreement with experimental dispersion data. Here we show how this long-standing difficulty with the formulation of Lagrangian stochastic models can be overcome. The new model is shown to be in good agreement with data from a carefully controlled, well-documented wind-tunnel study of scalar dispersion within plant canopy turbulence. Equally good agreement with this data is obtained using Thomson's (1987) Gaussian model. This bolsters confidence in the application of this simple model to the prediction of spore dispersal within plant canopy turbulence. Contact distributions—the probability distribution function for the distance of viable fungal spore movement until deposition—are predicted to have “heavy” inverse power-law tails. It is known that heavy-tailed contact distributions also characterize the dispersal of spores which pass through the canopy turbulence and enter into the overlying atmospheric boundary-layer. Plant disease epidemics due to the airborne dispersal of fungal spores are therefore predicted to develop as accelerating waves over a vast range of scales—from the within field scale to intercontinental scales. This prediction is consistent with recent analyses of field and historical data for rusts in wheat. Such plant disease epidemics are shown to be governed by space-fractional diffusion equations and by Lévy flights.
Structure and thermal expansion of sulfuric acid octahydrate
Authors: Maynard-Casely Helen E. , Brand Helen E. A. , Wallwork Kia S.
Published: October 2012

Synchrotron X-ray powder diffraction has been used to structurally characterize crystallization products from 37.8 and 40.5 wt% aqueous sulfuric acid solutions. It is confirmed that, despite speculation in the literature, the structure that predominately crystallized from these solutions is sulfuric acid octahydrate (SAO). The existence of an uncharacterized phase is also noted. It was found that existing models proposed for the crystal structure of SAO did not satisfactorily fit to the data acquired here, and hence a new structure solution was sought. It is reported here that the structure of SAO is contained within a unit cell withI2 symmetry witha= 7.44247 (11),b= 7.4450 (1),c= 26.1168 (3) Å, β = 125.0428 (7)°,V= 1184.78 (3) Å3at 80 K. Data were collected at temperatures between 80 and 198 K, which enabled determination of the thermal expansion of SAO.
Pitfalls of local and quantitative phase analysis in partially stabilized zirconia
Authors: Martin Stefan , Berek Harry , Aneziris Christos G. , Martin Ulrich , Rafaja David
Published: October 2012

The addition of selected elements into the host structure of ZrO2stabilizes the tetragonal and cubic phases of zirconia, which are, in their undoped binary form, only stable at high temperatures. From the crystallographic point of view, the increasing amount of the stabilizer causes a continuous transition of the tetragonal zirconia to its cubic modification. In partially stabilized zirconia, local concentration gradients of the stabilizer are frequently present as a consequence of the production process, which results in a coexistence of zirconia domains having different degrees of tetragonality. The presence of the local concentration gradients in such samples and the continuous nature of the phase transformation are features important for many technological applications, but their analysis is not straightforward. Furthermore, these features complicate the quantitative phase analysis in partially stabilized zirconia. For the example of zirconia partially stabilized by magnesium, this contribution illustrates the capabilities and limitations of X-ray and electron backscatter diffraction. In particular, the ability of these experimental methods to reveal the gradual lattice distortion that is associated with the cubic to tetragonal phase transformation in zirconia and the reliability of the quantitative phase analysis are discussed. In this context, it is shown to what extent the choice of the microstructure model influences the result of the phase analysis.
Diffraction microcomputed tomography of an Al-matrix SiC-monofilament composite
Authors: Stock Stuart R. , Almer Jonathan D.
Published: October 2012

The structure of an SiC-monofilament-reinforced Al-matrix composite was reconstructed using diffraction rings from these two phases. A 65 keV X-ray beam with 15 µm width (horizontal) and 150 µm length (vertical) was scanned across the specimen in 15 µm steps. A 2° rotation about the vertical rotation axis was used between projections, and filtered back projection reconstructions were created with 15 × 15 µm in-plane and 150 µm out-of-plane volume elements (voxels). The integrated intensities of the 11.0, 10.1 and 10.2 SiC and the 111, 200 and 220 Al diffraction rings were used to produce six independent reconstructions. The transmitted-intensity reconstruction agreed with that of higher resolution, absorption-contrast synchrotron microcomputed tomography. The Al reconstructions showed the effect of large grains, and the SiC reconstructions revealed the two microstructural zones in the fibers.
Anbar Abstracts Issue
Authors: Fojt Martin
Published: October 2012

This special “Anbar Abstracts” issue of the International Journal of Manpower is split into seven sections covering abstracts under the following headings: Human Resource Management; Career Planning & Recruitment; Women/Dependant Care; Health & Safety ; Education &Training ; Industrial Relations & Participation ; Redundancy.
Patron‐driven e‐book use and users' e‐book perceptions: a snapshot
Authors: McLure Merinda , Hoseth Amy
Published: October 2012

Purpose

This paper aims to provide a snapshot of student and staff attitudes towards e‐books, collected through a web‐based survey, as well as an analysis of use data for a specific universe of e‐books provided via a patron‐driven purchasing model and accessed during the survey timeframe.

Design/methodology/approach

This research analyzed survey responses collected from May 2010 to December 2010 and use data for the universe of e‐books made accessible via PDA, and used by library patrons, during this period.

Findings

E‐books are no longer a new phenomenon and the CSU Libraries have provided access to e‐books for many years, yet users' prior experience with e‐books, perspectives on desirable and undesirable e‐book characteristics, and preferences for print versus e‐books as provided by the libraries continue to vary. During the libraries' initial entry into PDA, e‐books made accessible to users via this model received more use through browsing than sustained use or download, but relatively little use overall. The study provides a starting point for the continued analysis of this library's PDA program, now the primary mechanism used to provide its academic user community with book access.

Practical implications

The authors present a review of the literature and research findings about academic users' interactions with, and preferences for, e‐books. They provide a point‐in‐time analysis of user interactions with e‐book titles made accessible via the libraries' PDA program and a subject‐level study of the use of these titles.

Originality/value

This paper presents point‐of‐use feedback regarding e‐books, from academic users, and detailed information about e‐book titles accessed via a PDA model.
Anbar Abstracts Issue
Authors: Fojt Martin
Published: October 2012

This special “Anbar Abstracts” issue of the International Journal of Bank Marketing is split into five sections covering abstracts under the following headings: Marketing Strategy and PR; Customer Service; Sales and Promotion; Product Development; Information Technology Strategies.
Strategies for service quality
Authors: Fojt Martin
Published: October 2012

That someone can make you feel good is a quality in itself. There has been much talk within British government circles for example, about the feel‐good factor, which is constantly reminding us that it is just around the corner! Whether or not we can believe in this is another matter, but it certainly displays an awareness that making other people feel good can also have positive benefits for you. How this can be achieved will differ depending on your particular line of business. Having a good quality product does not in itself guarantee success as service quality must also be taken into account. This is where the feel‐good factor comes into play. It is all very well, for example, going to a restaurant to have a top class meal, in that the food was good, only to have it thrown at you. Quality, therefore, must not be seen as a separate entity, but more as a package deal.
Industrial Training and Quality Initiatives
Authors: Sandelands Eric
Published: October 2012

Total quality management does improve organizational performance and remains the most viable long‐term business strategy around. These were the findings of a
recent report entitled “TQM: Forging a Need or Falling Behind?”, commissioned by Development Dimensions International of Pittsburgh, the Quality & Productivity Management Association of Schaumburg, Illinois, and Industry Week, which were based on interviews with 6,500 people in 84 organizations. However, on considering
the various elements which help or hinder TQM implementation, training emerged as the one successful theme in successful programmes.
Problematic customers and turnover intentions of customer service employees
Authors: Poddar Amit , Madupalli Ramana
Published: October 2012

Purpose

The purpose of this paper is to examine the effects of problematic customer behaviors on customer service employee attitudes and subsequent turnover intentions from the organization and also the occupation.

Design/methodology/approach

Data from five semi‐structured depth interviews and 215 quantitative surveys using structured questionnaires were used to develop and test the theoretical model. Customer service employees working in different call center companies serving American customers were approached using an established survey panel.

Findings

Results using the partial least squares (PLS) methodology showed that problematic customer behaviors drain customer service employees emotionally. Emotional exhaustion is negatively related to job satisfaction, and subsequently, employees' turnover intentions. The results also show that turnover intentions with organization and occupation are positively related to each other.

Research limitations/implications

As regards implications, this study provides an understanding of the relationship between problematic customer behaviors and employees' turnover intentions. Future researchers can utilize the findings from this study for investigating other consequences and antecedents of problematic customer behaviors. A limitation of the study is its use of cross‐sectional data.

Practical implications

This paper provides call center managers with an understanding of the effects of problematic customer behaviors on employee attitudes. It discusses the need for understanding problematic customers and ways to manage the effects of such experiences.

Originality/value

The study investigates an under‐researched phenomenon, i.e. problematic customer behaviors. The study provides evidence of the relationship between problematic customer behaviors and turnover intentions in service employees. This study is also one of very few in marketing to investigate the relationship between organizational and occupational turnover intentions.
Leadership style and team processes as predictors of organisational learning
Authors: Bhat Aruna B. , Verma Neha , Rangnekar S. , Barua M.K.
Published: October 2012

Purpose

This paper aims to explore the independent and interactive leadership style and team processes on organisational learning in an Indian context.

Design/methodology/approach

The methodology used is survey based. Primary data were collected from 36 Indian manufacturing sector executives and in total there were three teams (n=11, n=13 and n=12).

Findings

It was found that overall leadership style and transactional leadership had significant positive impact on organisational learning. Furthermore, team processes like cohesion and support and confrontation and problem solving were also found to be important predictors of organisational learning. The interactive effect of independent variables on dependent variable was also positive and significant.

Research limitations/implications

Discussions are performed and conclusions are drawn in the light of existing literature. The study bears implications for researchers to take on similar research in other contexts.

Practical implications

The study bears significant implications for executives working in manufacturing organisations. It is suggested that transactional leadership style should be employed to contribute towards organisational learning in such firms. Moreover, the use of team processes will also help in enhancing learning at the team and organisational levels.

Originality/value

This paper identifies two significant criterion variables to predict organisational learning. It is a pioneering effort to use team processes and leadership style together as predictors of organisational learning in Indian context.
Conflict management and effectiveness in virtual teams
Authors: Pazos Pilar
Published: October 2012

Purpose

This paper aims to explore the role of goal‐oriented attitudes and behaviors as antecedents of conflict management and the subsequent impact of conflict management on team outcomes in virtual teams. Of particular interest is the role of “commitment to team goals” as a predictor of successful conflict management and the subsequent impact of conflict management on team outcomes.

Design/methodology/approach

This paper describes the results from a quasi‐experimental study examining the relationships among commitment to team goals, conflict management and team outcomes in virtual teams. First, it provides an in depth review of relevant empirical findings. Next, it describes a study examining the relationships between three sets of variables: commitment to team goals; conflict management; and team outcomes (performance and attitudinal) in the context of virtual teams. Data were collected from 141 students grouped in 39 teams size 3 to 4 that were part of four cohorts of an Engineering Management course.

Findings

The results provide some preliminary evidence that conflict management mediated the relationships between goal commitment and team outcomes. Results suggest that commitment to team goals is a significant predictor of successful conflict management. Findings also suggest that teams that are more actively involved in preventing and solving their conflict experience a significant increase in the relationship between commitment to team goals and team performance, suggesting that use of effective conflict management can support team effectiveness in the context of virtual teams. Finally, limitations and suggestions for future research are presented.

Originality/value

This paper sheds some light into the role conflict as a mediator on the relationship between goal commitment and virtual team effectiveness. It provides preliminary evidence that conflict management plays a critical role in enhancing virtual team effectiveness.
Intellectual capital transformation evaluating model
Authors: Molodchik Mariya , Shakina Elena , Bykova Anna
Published: October 2012

Purpose

The purpose of this paper is to present a framework that is developed for analysis of intellectual capital transformation into companies’ value, including an identification of the key factors of this process.

Design/methodology/approach

The paper employs intellectual capital on the intersection of value‐based management (VBM) and the resource‐based view (RBV). Starting from a review of the results provided in the literature regarding intellectual capital (IC) evaluation and its link with firm performance, a system of proxy indicators related to IC transformation in both concepts has been designed. The evaluation ability of the developed model was justified using regression analyses.

Findings

A detailed algorithm for intellectual capital evaluation in terms of input‐outcome transformation. The intellectual capital transformation evaluating model (ICTEM) provides a holistic view of intellectual resources as companies’ strategic investments.

Research limitations/implications

The paper emphasizes that the ICTEM framework could be mostly applied for the analysis of a firm as a typical representative of the industry or the country. In that sense it is not applicable for specific feature analysis of a company.

Practical implications

The paper highlights the ICTEM as a tool of investment decisions, mostly taking into account common trends, the prospects of industries, and economies’ development.

Originality/value

The ICTEM provides the ostensive framework of intellectual capital transformation analysis using a statistical approach.
Intellectual capital as competitive advantage in emerging clusters in Latin America
Authors: Jardon Carlos M. , Susana Martos Maria
Published: October 2012

Purpose

Emerging clusters, formed by small to medium‐sized enterprises (SMEs) of slow growth and embryonic management systems present a different competitive advantage scheme. The purpose of this paper is to analyze relationships among components of intellectual capital within a model of competitive advantages in emerging clusters in a region of Latin America.

Design/methodology/approach

An intellectual capital model in a competitive advantage scheme is defined. A sequential method based in PLS technique is suggested to select the model and estimate the parameters. A sample of 113 wood manufacturing SMEs in a region of Argentina was selected.

Findings

The competitive advantage scheme in emerging clusters of SMEs proposes that resources affect organizational capabilities; territory and organizational capabilities affect strategic factors which improve performance. In this scheme, human capital affects structural capital and structural capital generates relational capital. SMEs organize tangible resources and relational capital to build organizational capabilities.

Research limitations/implications

The sample is a cross‐section. The performance is subjectively measured by the satisfaction of the entrepreneurs with different items.

Practical implications

The paper establishes suggestions to strategies of the SMEs in emerging clusters and politics of developing countries. This paper enables practitioners and scholars to comprehend and make legitimate decisions and conclusions that can foster business growth.

Originality/value

The authors tested the impact of dimensions of intellectual capital on performance in emerging clusters of developing countries within a competitive advantage scheme, showing relationships among intellectual capital dimensions and competitive advantages. The analysis differentiates between intellectual capital dimension and organizational capabilities.
Use of IC information in Japanese financial firms
Authors: Holland John , Henningsson Johan , Johanson Ulf , Koga Chitoshi , Sakakibara Shigeki
Published: October 2012

Purpose

The purpose of this paper is to explore the perceptions of: how Japanese financial firms (JFF) acquire and use company intellectual capital (IC) information in their common routine equity investment decisions, how this activity contributes to knowledge creation in the JFFs, and how investee company knowledge creation is affected by the JFFs.

Design/methodology/approach

The research employed a multi‐case design, using four JFF cases. The investigation was performed in terms of Nonaka and Toyama's “theory of the knowledge creating firm”.

Findings

IC information contributed to earnings estimates and company valuation. Emotional information contributed to JFF feelings and confidence in their information use and valuation. JFF knowledge was an important component of the key interacting and informed contexts used by JFFs. This generated opportunities to improve disclosure and accountability between JFFs and their investee companies. Common patterns of behaviour across the JFFs were counterbalanced by variety and differences noted in JFF behaviour.

Practical implications

The findings provide important insights into how JFF knowledge creating patterns could limit or progress a common language of communication between companies and markets on the subject of IC. This could impact on the quality of corporate disclosure and accountability processes.

Originality/value

The paper demonstrates that there is a need for further use of qualitative studies of financial market behavior. Especially in the area of understanding the communication of IC between firms and financial markets, the potential of using sociology of finance approaches appears to be considerable.
Intellectual capital disclosures by Indian and Australian information technology companies
Authors: Joshi Mahesh , Singh Ubha Dharminder , Sidhu Jasvinder
Published: October 2012

Purpose

The purpose of this paper is to investigate and compare the voluntary reporting of intellectual capital (IC) by the top 20 software and technology sector companies in a developing nation, India, and a developed nation, Australia. The paper aims to highlight the differences in IC disclosure practices of the companies operating in two different economies.

Design/methodology/approach

The study investigates the top 20 firms by market capitalisation listed on the Bombay Stock Exchange in India and the Australian Stock Exchange in Australia in the year 2007‐2008. Using the content analysis method, the paper reviews the annual reports of these firms to determine IC disclosure trends in India and Australia. Statistical tools and graphs have been used to compare and contrast ICD disclosures in two countries.

Findings

The study has identified IC disclosure differences between Indian and Australian firms, and reports disclosures by Indian companies are on a higher scale than Australian Software and Technology Sector companies. However, Levels of voluntary IC disclosure are found to be low in both the nations and most of the disclosures are declarative in nature.

Research limitations/implications

This lack of consistency in reporting practices makes comparisons across countries difficult. The paper emphasises the need for a uniform and consistent framework for the reporting of intellectual capital items.

Practical implications

The results of this exploratory study on the knowledge based industrial sector can be used by researchers to explore different types of IC reporting initiatives pursued across specifically knowledge based industrial sectors.

Originality/value

This study offers insights into comparative trends in IC disclosure practices of software and technology sector companies operating in a developed and a developing country.
The inter‐disciplinary modelling of supply chains in the context of collaborative multi‐structural cyber‐physical networks
Authors: Ivanov Dmitry , Sokolov Boris
Published: October 2012

Purpose

On modern markets, supply chains (SC) shape the competition landscape. At the same time, considerable research advancements have been recently achieved in the area of collaborative networks. Trends in information technology progress for networked systems include development of cyber‐physical networks, cloud service environments, etc. The purpose of this paper is to identify an inter‐disciplinary perspective and modelling tools for new generation SCs which will be collaborative cyber‐physical networks.

Design/methodology/approach

This study addresses the above‐mentioned research goal by first, developing a methodical vision of an inter‐disciplinary modelling framework for SCM based on the existing studies on SC operations, control and systems theories; and second, by integrating elements of different structures with structures dynamics within an adaptive framework based upon the authors' own research.

Findings

The inter‐disciplinary modelling framework for multi‐structural SCs has been developed. A new inter‐disciplinary level of model‐based decision‐making support in those SCs is claimed based on the integration of previously isolated problems and modelling tools developed in such disciplines like operations research, control theory, system dynamics, and artificial intelligence.

Originality/value

The novelty of this paper is the consideration of SC modelling in the context of collaborative cyber‐physical systems. This topic is particularly relevant for researchers and practitioners who are interested in future generation SCs. Particular focus is directed towards the multi‐structural SC modelling, structure dynamics, and inter‐disciplinary problems and models in future SCs. Challenges of integrated optimization in the organizational and informational context are discussed.
Appraising interdisciplinary contributions to theory for collaborative (manufacturing) networks
Authors: Dekkers Rob , Kühnle Hermann
Published: October 2012

Purpose

Progress in theory building in the field of collaborative networks in manufacturing is preponderantly seen in contributions from disciplines outside manufacturing science. Interdisciplinary research is one way of accelerating the development of appropriate theory for this emerging domain where industrial practice has moved beyond the state of the art of scientific knowledge for establishing workable, competitive solutions. The purpose of this paper is to examine to what extent interdisciplinary research has contributed to a better understanding of collaborative (manufacturing) networks.

Design/methodology/approach

To find out more about provenances of on‐going studies, to identify clusters of contributions and to provide direction for future work of researchers in this domain, publications of the past 22 years have been evaluated. To retrieve these contributions, a structured literature review has been undertaken by applying keywords to selected databases and using a strictly defined stepwise procedure. In total, 202 publications of all kinds have been evaluated.

Findings

From the analysis of the results, it appears that most interdisciplinary contributions to collaborative (manufacturing) networks rely on one original outside discipline for either developing solutions or advancing theoretical insight. Consequently, and after further analysis, it seems that researchers in collaborative networks hardly resort to multi‐disciplinary approaches, unless “natural”; further advances might arrive from stimulating these multi‐disciplinary avenues rather than sticking to more mono‐disciplinary, and less risky, takes on both applications and theoretical insight. A more detailed investigation of the value of contributions reveals that efforts to make interdisciplinary advances are either difficult or limited. Also, the findings indicate that researchers tend to follow a more “technical” approach to decision making by actors in networks rather than searching for a shift in paradigm.

Originality/value

While setting out these directions for future research and guiding research, this first‐of‐its‐kind review introduces the collaboration model as a systematic approach to collaborative (manufacturing) networks. This model might serve as a reference model to integrate disciplines for addressing the characteristics of Collaborative Networks. Its use in the review led to the finding that typical traits of networks, such as changeability, supplementary assets and decentralisation of decision making, are under‐researched.
Lessons learned from the lifecycle management of collaborative enterprises networks
Authors: Cheikhrouhou Naoufel , Pouly Michel , Huber Charles , Beeler Jean
Published: October 2012

Purpose

Research on the dynamics of Collaborative Enterprises Networks (CEN) lacks consistency and industrial feedback. The purpose of this paper is to present insights and lessons learned from an industrial case study dealing with the practical experience gathered during the creation, alliance development, and business operation phases of a CEN.

Design/methodology/approach

The proposed research methodology relies on qualitative approach, using unstructured interviews with the main decision makers in the network. The objective of the interviews is to highlight the most important events in the lifecycle of the network. From the important elements discussed, success and failure key factors are identified.

Findings

Through the case study, the authors identify the main success and failure key factors to consider in CENs. Furthermore, relying on the current state of the art, they highlight the main research directions, particularly with respect to the development of modelling approaches capturing the dynamics of these systems.

Originality/value

The identification of the success and failure key factors and their corresponding technologies, systems and human perspectives is aimed at providing links between theoretical models and practical implications to both academics and industrialists. The challenges and developmental areas proposed provide the basis for new models capturing the dynamics and the evolution of CENs.
Chinese online literature: creative consumers and evolving business models
Authors: Ren Xiang , Montgomery Lucy
Published: October 2012

Purpose

The internet is transforming possibilities for creative interaction, experimentation and cultural consumption in China and raising important questions about the role that “publishers” might play in an open and networked digital world. The purpose of this paper is to consider the role that copyright is playing in the growth of a publishing industry that is being “born digital”.

Design/methodology/approach

The paper approaches online literature as an example of a creative industry that is generating value for a wider creative economy through its social network market functions. It builds on the social network market definition of the creative industries proposed by Pottset al.and uses this definition to interrogate the role that copyright plays in a rapidly‐evolving creative economy.

Findings

The rapid growth of a market for crowd‐sourced content is combining with growing commercial freedom in cultural space to produce a dynamic landscape of business model experimentation. Using the social web to engage audiences, generate content, establish popularity and build reputation and then converting those assets into profit through less networked channels appears to be a driving strategy in the expansion of wider creative industries markets in China.

Originality/value

At a moment when publishing industries all over the world are struggling to come to terms with digital technology, the emergence of a rapidly‐growing area of publishing that is being born digital offers important clues about the future of publishing and what social network markets might mean for the role of copyright in a digital age.
Cultural consumption and souvenirs: an ethical framework
Authors: Brennan Linda , Savage Theresa
Published: October 2012

Purpose

The purpose of this paper is to propose guidelines for business enterprises engaging with indigenous communities to protect their intellectual property rights, particularly indigenous art works produced for the souvenir industry.

Design/methodology/approach

Literature on indigenous art and souvenirs demonstrating exploitation of indigenous communities’ intellectual property was facilitated by a lack of knowledge of how to otherwise behave. The proposed guidelines for commercial entities wishing to engage ethically with indigenous communities draws on international exemplars.

Findings

A twelve‐point framework for ethical commerce in indigenous souvenirs between indigenous communities and businesses is proposed to ensure populations lacking economic and social power are not disenfranchised by limited experience in a market society.

Social implications

The proposed guidelines contribute to achieving reconciliation between mainstream and indigenous people in various countries throughout the world.

Originality/value

This paper assists development of guidelines enabling ethical decision‐making in the souvenir industry applying a critical approach to the principles of corporate responsibility.
Metabolomics of hexachlorocyclohexane (HCH) transformation: ratio of LinA to LinB determines metabolic fate of HCH isomers
Authors: Geueke Birgit , Garg Nidhi , Ghosh Sneha , Fleischmann Thomas , Holliger Christof , Lal Rup , Kohler Hans‐Peter E.
Published: October 2012

Although the production and use of technical hexachlorocyclohexane (HCH) and lindane (the purified insecticidal isomer γ‐HCH) are prohibited in most countries, residual concentrations still constitute an immense environmental burden. Many studies describe the mineralization of γ‐HCH by bacterial strains under aerobic conditions. However, the metabolic fate of the other HCH isomers is not well known. In this study, we investigated the transformation of α‐, β‐, γ‐, δ‐, ε‐HCH, and a heptachlorocyclohexane isomer in the presence of varying ratios of the two enzymes that initiate γ‐HCH degradation, a dehydrochlorinase (LinA) and a haloalkane dehalogenase (LinB). Each substrate yielded a unique metabolic profile that was strongly dependent on the enzyme ratio. Comparison of these results to those of in vivo experiments with different bacterial isolates showed that HCH transformation in the tested strains was highly optimized towards productive metabolism of γ‐HCH and that under these conditions other HCH‐isomers were metabolized to mixtures of dehydrochlorinated and hydroxylated side‐products. In view of these results, bioremediation efforts need very careful planning and toxicities of accumulating metabolites need to be evaluated.
Dryland biological soil crust cyanobacteria show unexpected decreases in abundance under long‐term elevated CO2
Authors: Steven Blaire , Gallegos‐Graves La Verne , Yeager Chris M. , Belnap Jayne , Evans R. David , Kuske Cheryl R.
Published: October 2012

Biological soil crusts (biocrusts) cover soil surfaces in many drylands globally. The impacts of 10 years of elevated atmospheric CO2 on the cyanobacteria in biocrusts of an arid shrubland were examined at a large manipulated experiment in Nevada, USA. Cyanobacteria‐specific quantitative PCR surveys of cyanobacteria small‐subunit (SSU) rRNA genes suggested a reduction in biocrust cyanobacterial biomass in the elevated CO2 treatment relative to the ambient controls. Additionally, SSU rRNA gene libraries and shotgun metagenomes showed reduced representation of cyanobacteria in the total microbial community. Taxonomic composition of the cyanobacteria was similar under ambient and elevated CO2 conditions, indicating the decline was manifest across multiple cyanobacterial lineages. Recruitment of cyanobacteria sequences from replicate shotgun metagenomes to cyanobacterial genomes representing major biocrust orders also suggested decreased abundance of cyanobacteria sequences across the majority of genomes tested. Functional assignment of cyanobacteria‐related shotgun metagenome sequences indicated that four subsystem categories, three related to oxidative stress, were differentially abundant in relation to the elevated CO2 treatment. Taken together, these results suggest that elevated CO2 affected a generalized decrease in cyanobacteria in the biocrusts and may have favoured cyanobacteria with altered gene inventories for coping with oxidative stress.
Pyoverdine biosynthesis and secretion in Pseudomonas aeruginosa: implications for metal homeostasis
Authors: Schalk Isabelle J. , Guillon Laurent
Published: October 2012

Pyoverdines are siderophores produced by fluorescent Pseudomonads to acquire iron. At least 60 different pyoverdines produced by diverse strains have been chemically characterized. They all consist of a dihydroquinoline‐type chromophore linked to a peptide. These peptides are of various lengths and the sequences are strain specific. Pyoverdine biosynthesis in Pseudomonas aeruginosa and fluorescent Pseudomonads is a complex process involving at least 12 different proteins, starting in the cytoplasm and ending in the periplasm. The cellular localization of pyoverdine precursors was recently shown to be consistent with their biosynthetic enzymes. In the cytoplasm, pyoverdine appears to be assembled at the inner membrane and particularly at the old cell pole of the bacterium. Mature pyoverdine is uniformly distributed throughout the periplasm, like the periplasmic enzyme PvdQ. Secretion of pyoverdine involves a recently identified ATP‐dependent efflux pump, PvdRT‐OpmQ. This efflux system does not only secrete newly synthesized pyoverdine but also pyoverdine that already transported iron into the bacterial periplasm and any pyoverdine–metal complex other than ferri‐pyoverdine present in the periplasm. This review considers how these new insights into pyoverdine biosynthesis and secretion contribute to our understanding of the role of pyoverdine in iron and metal homeostasis in fluorescent Pseudomonads.
TheTOLnetwork ofPseudomonas putidamt‐2 processes multiple environmental inputs into a narrowresponse space
Authors: Silva‐Rocha Rafael , de Lorenzo Víctor
Published: October 2012

TheTOLsystem encoded by plasmidpWW0ofPseudomonas putidamt‐2 is able to sense a large number of both exogenous and endogenous signals as inputs for the genetic and metabolic circuit that determines the biodegradation ofm‐xylene. However, whether the enormous combinatorial space of inputs is translated into an equally variable response landscape or is processed into very few outcomes remains unclear. To address this question, we set out to define the number of states that can be obtained by a network of a given set of genes under the control of a specified regulatory circuit that is exposed to all possible combinations of inputs. To this end, theTOLnetwork and its regulatory wiring were formalized as a synchronous logicBoolean circuit that had 10 signals (i.e. pathway substrates, temperature, sugars, amino acids, metabolic regimes and global regulators) as possible inputs. The analysis of the attractors of the circuit using a satisfiability (SAT) algorithm revealed that only eight transcriptional states are reached in response to the 1024 possible combinations of stimuli. The experimental validation resulted in a refinement of the model through the addition of a previously unknown interaction that controls themetacatabolic pathway. The full induction of the twoxyloperons occurred with only 1.6% of the input combinations, which suggests that the architecture of the network allows the expression of thexylgenes only under a very narrow range of conditions. These data not only explain much of the unusual layout of theTOLcircuit but also strengthen the view of the regulatory circuits of environmental bacteria as digital decision‐making devices.
Active sulfur cycling by diverse mesophilic and thermophilic microorganisms in terrestrial mud volcanoes of Azerbaijan
Authors: Green‐Saxena A. , Feyzullayev A. , Hubert C. R. J. , Kallmeyer J. , Krueger M. , Sauer P. , Schulz H.‐M. , Orphan V. J.
Published: October 2012

Terrestrial mud volcanoes (TMVs) represent geochemically diverse habitats with varying sulfur sources and yet sulfur cycling in these environments remains largely unexplored. Here we characterized the sulfur‐metabolizing microorganisms and activity in four TMVs in Azerbaijan. A combination of geochemical analyses, biological rate measurements and molecular diversity surveys (targeting metabolic genes aprA and dsrA and SSU ribosomal RNA) supported the presence of active sulfur‐oxidizing and sulfate‐reducing guilds in all four TMVs across a range of physiochemical conditions, with diversity of these guilds being unique to each TMV. The TMVs varied in potential sulfate reduction rates (SRR) by up to four orders of magnitude with highest SRR observed in sediments where in situ sulfate concentrations were highest. Maximum temperatures at which SRR were measured was 60°C in two TMVs. Corresponding with these trends in SRR, members of the potentially thermophilic, spore‐forming, Desulfotomaculum were detected in these TMVs by targeted 16S rRNA analysis. Additional sulfate‐reducing bacterial lineages included members of the Desulfobacteraceae and Desulfobulbaceae detected by aprA and dsrA analyses and likely contributing to the mesophilic SRR measured. Phylotypes affiliated with sulfide‐oxidizing Gamma‐ and Betaproteobacteria were abundant in aprA libraries from low sulfate TMVs, while the highest sulfate TMV harboured 16S rRNA phylotypes associated with sulfur‐oxidizing Epsilonproteobacteria. Altogether, the biogeochemical and microbiological data indicate these unique terrestrial habitats support diverse active sulfur‐cycling microorganisms reflecting the in situ geochemical environment.
Fine‐scale degrader community profiling over an aerobic/anaerobic redox gradient in a toluene‐contaminated aquifer
Authors: Larentis Michael , Hoermann Katrin , Lueders Tillmann
Published: October 2012

Hydrocarbon contaminants in groundwater can be degraded by microbes under different redox settings, forming hot spots of degradation especially at the fringes of contaminant plumes. At a tar‐oil‐contaminated aquifer in Germany, it was previously shown that the distribution of anaerobic toluene degraders as traced via catabolic and ribosomal marker genes is highly correlated to zones of increased anaerobic degradation at the lower fringe of the plume. Here, we trace the respective distribution of aerobic toluene degraders over a fine‐scale depth transect of sediments taken at the upper fringe of the plume and below, based on the analysis of 16S rRNA genes as well as catabolic markers in intervals of 3–10 cm. Well‐defined small‐scale distribution maxima of typical aerobic degrader lineages within the Pseudomonadaceae, Comamonadaceae and Burkholderiaceae are revealed over the redox gradient. An unexpected maximal abundance of 9.2 × 106 toluene monooxygenase (tmoA) genes per g of sediment was detected in the strongly reduced plume core, and gene counts did not increase towards the more oxidized upper plume fringe. This may point towards unusual ecological controls of these yet unidentified aerobic degraders, and indicates that competitive niche partitioning between aerobic and anaerobic hydrocarbon degraders in the field is not yet fully understood. These findings demonstrate the potential of catabolic marker gene assays in elaborating the ecology of contaminant plumes, which is a prerequisite for developing integrated monitoring strategies for natural attenuation.
Office Size of Big 4 Auditors and Client Restatements
Authors: Francis Jere R. , Michas Paul N. , Yu Michael D.
Published: October 2012

Francis and Yu (2009) and Choi, Kim, Kim, and Zang (2010) report evidence that Big 4 audits are of higher quality when the engagement office is of larger size. Specifically, client earnings quality is higher and auditors in larger offices are more likely to issue going‐concern audit reports. We extend this line of research to test if larger Big 4 offices have fewer client restatements. A client restatement provides more direct evidence of a low‐quality audit than earnings quality metrics or going‐concern reports, because a restatement indicates the client's auditor did not effectively enforce the correct application of GAAP at the time the original financial statements were issued. We analyze 2,557 firm‐year restatements in a sample of 23,190 financial statements originally issued by U.S. firms from 2003 to 2008. We find that Big 4 office size is associated with fewer client restatements after controlling for innate client characteristics that may affect restatements (client size, financial performance, industry membership, nonfinancial measures, off‐balance sheet activities, and market‐related measures), and a set of controls for other auditor factors such as fees and industry expertise. The study raises important questions about the ability of smaller offices to deliver high‐quality audits for SEC registrants.
Neuropeptides and diabetic retinopathy
Authors: Gábriel Robert
Published: October 2012

Diabetic retinopathy, a common complication of diabetes, develops in 75% of patients with type 1 and 50% of patients with type 2 diabetes, progressing to legal blindness in about 5%. In the recent years, considerable efforts have been put into finding treatments for this condition. It has been discovered that peptidergic mechanisms (neuropeptides and their analogues, activating a diverse array of signal transduction pathways through their multiple receptors) are potentially important for consideration in drug development strategies. A considerable amount of knowledge has been accumulated over the last three decades on human retinal neuropeptides and those elements in the pathomechanisms of diabetic retinopathy which might be related to peptidergic signal transduction. Here, human retinal neuropeptides and their receptors are reviewed, along with the theories relevant to the pathogenesis of diabetic retinopathy both in humans and in experimental models. By collating this information, the curative potential of certain neupeptides and their analogues/antagonists can also be discussed, along with the existing clinical treatments of diabetic retinopathy. The most promising peptidergic pathways for which treatment strategies may be developed at present are stimulation of the somatostatin‐related pathway and the pituitary adenylyl cyclase‐activating polypeptide‐related pathway or inhibition of angiotensinergic mechanisms. These approaches may result in the inhibition of vascular endothelial growth factor production and neuronal apoptosis; therefore, both the optical quality of the image and the processing capability of the neural circuit in the retina may be saved.
Revealing children's implicit spelling representations
Authors: Critten Sarah , Pine Karen J. , Messer David J.
Published: October 2012

Conceptualizing the underlying representations and cognitive mechanisms of children's spelling development is a key challenge for literacy researchers. Using the Representational Redescription model (Karmiloff‐Smith), Critten, Pine and Steffler (2007) demonstrated that the acquisition of phonological and morphological knowledge may be underpinned by increasingly explicit levels of spelling representation. However, their proposal that implicit representations may underlie early ‘visually based’ spelling remains unresolved. Children (N = 101, aged 4–6 years) were given a recognition task (Critten et al., 2007) and a novel production task, both involving verbal justifications of why spellings are correct/incorrect, strategy use and word pattern similarity. Results for both tasks supported an implicit level of spelling characterized by the ability to correctly recognize/produce words but the inability to explain operational strategies or generalize knowledge. Explicit levels and multiple representations were also in evidence across the two tasks. Implications for cognitive mechanisms underlying spelling development are discussed.