bluuebunny/crossref_metadata_2025 huggingface dataset:
Epitaxial growth and structural analysis of AlN∕GaN heterostructures
Authors: Yao Z. Q. , Zou Y. S. , Yang Y. , Zhang W. J. , Lee S. T. , Zhang Y. Z. , Ye Z. Z.
Published: December 2007

Single crystal AlN thin films were epitaxially grown on GaN/sapphire (0001) substrates on a macroscopic scale by magnetron sputtering. The microscopic structure and orientation degree of the AlN epilayers were studied by high-resolution transmission electron microscopy, high-resolution x-ray diffraction, and reciprocal spacing mapping. It was revealed that the AlN epilayers have high in-plane and out-of-plane orientation degrees and low defect density. The electrical and optical properties of the AlN epilayers were also studied, and the results suggest that the AlN epilayers grown by sputtering may be employed in the fabrication of GaN-based light-emitting diode devices with increased efficiency.
Mechanism for generation of the phonon-energy-coupling enhancement effect for ultrathin oxides on silicon
Authors: Chen Zhi
Published: December 2007

Large leakage-current reduction of SiO2 due to the phonon-energy-coupling enhancement effect was confirmed by measuring the oxide thickness using a cross-sectional transmission electron microscopy. There is a critical temperature Tc. Rapid thermal processing (RTP) of SiO2 at T>Tc in pure N2 leads to a destructive structure with large leakage current, while RTP at T<Tc in pure N2 does not change the oxide structure. After introducing a little amount of oxygen during RTP, the destructive structure can be converted to a constructive one by repairing the defects created during RTP at T>Tc. This leads to reduced leakage current.
Enhanced friction of elastomer microfiber adhesives with spatulate tips
Authors: Kim Seok , Aksak Burak , Sitti Metin
Published: December 2007

Previous studies have demonstrated that gecko foot-hair inspired elastomer microfibers with spatulate tips have significant adhesion enhancement compared to the flat elastomer surface. In this study, we report the friction enhancement of these highly adhesive fibers and analyze the relation between adhesion and friction of elastomer microfiber arrays with spatulate tips. Fabricated polyurethane fiber arrays with spatulate tips demonstrate macroscale static friction pressures up to 41N∕cm2 for a preload pressure of 1.5N∕cm2 on a 6mm diameter smooth glass hemisphere.
Make a Kit, Make a Plan, Stay Informed: Using Social Marketing to Change the Population's Emergency Preparedness Behavior
Authors: Marshall Robert J. , Petrone Laurie , Takach Mary Jo , Sansonetti Shannon , Wah-Fitta Maria , Bagnall-Degos Andrea , Novais Ana
Published: December 2007

The population's response to a public health emergency can mean the difference between an incident and a tragedy. As the community's health educators, public health agencies promote “productive behaviors” to avoid panic during anxiety-producing situations. The Rhode Island Department of Health used a social marketing approach to identify the public's “wants and needs” in anticipation of an emergency. The formative research included age and race/ethnicity-specific focus groups and in-depth interviews with representatives of agencies serving special populations to determine information needs, preferred formats, trusted sources, and other aspects of emergency preparedness. Program staff used this information to design and bulk mail an initial pre-intervention awareness flyer and, months later, a 32-page informational booklet called “Make a Kit, Make a Plan, Stay Informed.” This “product” provided the population with three key preparedness behaviors out of the extensive range of options. Evaluation of the booklet indicated that an estimated 10% of the population changed their behavior by engaging in one of more of the preparedness activities. The authors conclude that social marketing provides a useful and systematic process for planning and implementing a project aimed at changing public health emergency preparedness behavior.
Capturing the Ripples: Addressing the Sustainability of the Impact of Social Marketing
Authors: Arulmani Gideon , Abdulla Agisa
Published: December 2007

This article reports the development and implementation of a social marketing campaign that was designed to address the interactions between employment seekers and employment providers in the Republic of Maldives. The campaign was implemented in an environment of negative mindsets among young people toward skill-based training and occupations. This in turn has resulted in employers preferring an expatriate workforce, leaving large numbers of Maldivian youth unemployed. Social marketing was used as a device to valorize the notion of work and career by promoting affirmative and positive attitudes toward work. A part of the overall strategy was a career counseling program which followed the campaign to build on this valorizing effect and provide a contextually grounded structure and system for making effective career choices. Based on the data gleaned from these interventions, the article examines the relative and combined impact of social marketing and career guidance on the targeted behaviors and attitudes. In its conclusion, the article discusses the role that social marketing could play along with a partner intervention to effect long-term behavioral and attitudinal change.
Metabolomics Reveals Novel Pathways and Differential Mechanistic and Elicitor-Specific Responses in Phenylpropanoid and Isoflavonoid Biosynthesis in Medicago truncatula Cell Cultures
Authors: Farag Mohamed A. , Huhman David V. , Dixon Richard A. , Sumner Lloyd W.
Published: December 2007

High-performance liquid chromatography coupled to ultraviolet photodiode array detection and ion-trap mass spectrometry was used to analyze the intra- and extracellular secondary product metabolome of Medicago truncatula cell suspension cultures responding to yeast elicitor (YE) or methyl jasmonate (MeJA). Data analysis revealed three phases of intracellular response to YE: a transient response in mainly (iso)flavonoid metabolites such as formononetin and biochanin-A that peaked at 12 to 18 h following elicitation and then declined; a sustained response through 48 h for compounds such as medicarpin and daidzin; and a lesser delayed and protracted response starting at 24 h postelicitation, e.g. genistein diglucoside. In contrast, most compounds excreted to the culture medium reached maximum levels at 6 to 12 h postelicitation and returned to basal levels by 24 h. The response to MeJA differed significantly from that to YE. Although both resulted in accumulation of the phytoalexin medicarpin, coordinated increases in isoflavonoid precursors were only observed for YE and not MeJA-treated cells. However, MeJA treatment resulted in a correlated decline in isoflavone glucosides, and did not induce the secretion of metabolites into the culture medium. Three novel methylated isoflavones, 7-hydroxy-6,4′-dimethoxyisoflavone (afrormosin), 6-hydroxy-7,4′-dimethoxyisoflavone (alfalone), and 5,7-dihydroxy-4′,6-dimethoxy isoflavone (irisolidone), were induced by YE, and labeling studies indicated that the first two were derived from formononetin. Our results highlight the metabolic flexibility within the isoflavonoid pathway, suggest new pathways for complex isoflavonoid metabolism, and indicate differential mechanisms for medicarpin biosynthesis depending on the nature of elicitation.
Micro-Electrode Flux Estimation Confirms That the Solanum pimpinellifolium cu3 Mutant Still Responds to Systemin
Authors: Lanfermeijer Frank C. , Staal Marten , Malinowski Robert , Stratmann Johannes W. , Elzenga J. Theo M.
Published: December 2007

In this study, we introduce the Micro-Electrode Ion Flux Estimation technique as a sensitive and accurate technique to study systemin-induced changes in ion fluxes from isolated nearly intact plant tissues. Our results demonstrate the effectiveness and value of the Micro-Electrode Ion Flux Estimation technique to monitor and characterize those elicitor-induced ion flux changes from intact tissues. We used the method to monitor the systemin-induced changes in ion fluxes from leaf tissue of various plant species, including wild-type and cu3 mutant tomato (Solanum pimpinellifolium) plants, and confirm previous observations, but now in intact leaf tissue. Upon exposure of leaf tissue of plant species from the subtribe solaneae to systemin, the H+ influx and K+ efflux were transiently strongly increased. Plant species of other clades did not show a response upon systemin exposure. Although it has been reported that the gene containing the cu3 null mutation is identical to the SR160/tBRI1 gene, which encodes the systemin/brassinosteroid receptor and is essential in systemin and brassinosteroid perception, we observed no differences in the response of H+ and K+ fluxes from both wild-type and mutant leaf tissue to systemin. Also, the effects of various pharmacological effectors on systemin-induced flux changes were similar. Moreover, a SR160/tBRI1 transgene-containing tobacco (Nicotiana tabacum) line was insensitive to systemin, whereas both this line and its wild-type predecessor were responsive to the elicitor flg22. Our results support the conclusion that the Cu3 receptor of tomato is not the systemin receptor, and, hence, another receptor is the principal systemin receptor.
VPS9a, the Common Activator for Two Distinct Types of Rab5 GTPases, Is Essential for the Development of Arabidopsis thaliana
Authors: Goh Tatsuaki , Uchida Wakana , Arakawa Satoko , Ito Emi , Dainobu Tomoko , Ebine Kazuo , Takeuchi Masaki , Sato Ken , Ueda Takashi , Nakano Akihiko
Published: December 2007

Rab5, a subfamily of Rab GTPases, regulates a variety of endosomal functions as a molecular switch. Arabidopsis thaliana has two different types of Rab5-member GTPases: conventional type, ARA7 and RHA1, and a plant-specific type, ARA6. We found that only one guanine nucleotide exchange factor (GEF), named VPS9a, can activate all Rab5 members to GTP-bound forms in vitro in spite of their diverged structures. In the vps9a-1 mutant, whose GEF activity is completely lost, embryogenesis was arrested at the torpedo stage. Green fluorescent protein (GFP)–ARA7 and ARA6-GFP were diffused in cytosol like GDP-fixed mutants of Rab5 in vps9a-1, indicating that both types of GTPase are regulated by VPS9a. In the leaky vps9a-2 mutant, elongation of the primary root was severely affected. Overexpression of the GTP-fixed form of ARA7 suppressed the vps9a-2 mutation, but overexpression of ARA6 had no apparent effects. These results indicate that the two types of plant Rab5 members are functionally differentiated, even though they are regulated by the same activator, VPS9a.
Gender pay equity, wage fixation and industrial relations reform in Australia
Authors: Lyons Michael , Smith Meg
Published: December 2007

Purpose

The purpose of this paper is to discuss the impact on the new federal wage fixing system on gender pay equity in Australia.

Design/methodology/approach

The article is divided into four parts. The first section briefly examines the policy approach to the issue of gender pay equity in other Anglophone counties and the history of pay (in)equity under the Australian tribunal based industrial relations system. The second section overviews the recent developments at the State level in Australia focused on gender pay equity. The third section discusses recent cases in State wage fixing systems in Australia designed to remedy the gender based undervaluation of children's services employees. The fourth and final section discusses the implications of the new “national” workplace relations laws in the context of gender pay equity in Australia.

Findings

The capacity of State tribunals to continue to apply gender free wage determinations is under threat because of the federal government's 2006 “reforms” to the Australian industrial relations and wage fixation systems.

Originality/value

The commissioned case studies and inquiries demonstrate that governments – and State Labor governments in particular – have placed the issue of the gender earnings gap on the policy agenda.
The changing nature of the HR function in UK local government and its role as “employee champion”
Authors: Harris Lynette
Published: December 2007

Purpose

Public sector reforms and external performance review has meant that the HR function in UK local government is not only expected to continuously review working practices but is also facing major changes in its role and its own service delivery. This paper explores how changes driven by the pursuit of efficiency and cost cutting may impact on the function's ability to fulfil the employee champion role that Ulrich identifies as essential to it making a valuable strategic contribution.

Design/methodology/approach

The findings are drawn from interviews, focus groups and desk research conducted in three large local authorities

Findings

The emergent concerns, tensions and dilemmas across the case study organisations suggest that changes, both planned and actual, to HR's role and services will impact on the function's ability to act as an “employee champion” due to reduced employee contact and more fragmented HR roles.

Research limitations/implications

The findings are based on three case studies, so there is an issue of their wider application – and they provided rather more insights into the views of HR staff and line managers than of other employee groups.

Practical implications

The devolved, decentralised, outsourced and self service models of HR service provision require careful internal evaluation as this study's findings indicate they may well have hidden costs in terms of promoting employee commitment in large public sector organisations.

Originality/value

A qualitative study of how changes to the HR function's role and service delivery can impact on the HR's responsibilities for employee relations rather than the more usual considerations of cost effectiveness and efficiency.
Training and cultural context in the Arab Emirates: fighting a losing battle?
Authors: Jones Stephanie
Published: December 2007

Purpose

The purpose of this paper is to explore the delivery of corporate objectives in customer service in the training of employees in a cultural context at odds with the proposed training outcomes.

Design/methodology/approach

A training program created to encourage collaborative and competitive styles in customer interaction, delivered in a major bank in the UAE, was the focus of the case.

Findings

A literature review suggests that collaborative and competitive styles (of all the five conflict mode preferences) are positively correlated with business performance. The overwhelming preference for compromising and avoiding styles found amongst trainees in this bank showed that specific cultural context can significantly modify the desired outcomes of Western‐style training programs. The conflict mode preferences seen to encourage collaborative and competitive styles were significantly below best‐practice averages in this case.

Research limitations/implications

Significant differences are discovered between the attitudes of the trainee group and the conflict mode preferences described in an international benchmarking study of excellence and quality in customer service.

Practical implications

The practical implications for training effectiveness in the Arab world (one of the largest consumers of corporate training worldwide) are explored, together with a study of how the current approaches to training in the region might be modified to improve training results.

Originality/value

This study of 70 UAE bank trainees suggests that in the task of trying to achieve corporate needs to increase efficiency, productivity and profitability, culture poses an important barrier. The paper provides further evidence of the importance of cultural context in management practices, in a little‐studied region of the world.
Creating a consumer market for scholarly journals
Authors: Nicholas David , Huntington Paul , Dobrowolski Tom , Rowlands Ian
Published: December 2007

Purpose

The purpose of this paper is to propose an alternative method for individuals to obtain documents using credits supplied by their institution to purchase at article level.

Design/methodology/approach

The paper draws on the experience and knowledge gained from the extensive work that CIBER has done in analyzing the usage of large‐scale journal databases.

Findings

It was found that such an approach has many advantages over the current librarian‐driven process.

Originality/value

Digital content is variously neglected, abused, free, and expensive. This paper is as much about stimulating some new thinking in this important area as about setting out a new scholarly communication market model.
Recent developments in Remote Document Supply (RDS) in the UK – 3
Authors: Prowse Stephen
Published: December 2007

Purpose

The purpose of this paper is to provide a review of recent developments in remote document supply and related matters in the UK.

Design/methodology/approach

The article is based on a range of articles, reports, papers and web sites.

Findings

With the decline in remote document supply the future participation of a key institution is called into question. While there are few other realistic options, the two leading alternatives are engaged in a battle for the same market. Furthermore, the future of key standard underpinning transactions is also uncertain.

Originality/value

The article provides an overview of current developments in UK document supply by an experienced practitioner.
On document supply in the digital world
Authors: Schöpfel Joachim , Gillet Jacqueline
Published: December 2007

Purpose

The purpose of this paper is to provide insight into the evolution of document supply from traditional print copy delivery to a modern service of resource discovery and secure electronic supply.

Design/methodology/approach

The study is based on evidence from empirical data at INIST, as well as enquiries and case studies from other suppliers and customers.

Findings

Four topics are presented: the customers' needs, the use of new technologies in the front‐ and back‐office, resource sharing and networking on the national and international level, and the negotiation of copyright agreements with publishers.

Originality/value

Based on evidence, an overall synthesis is given on significant developments, providing outlines of the future of document supply.
Interlending and document supply: a review of the recent literature: 61
Authors: McGrath Mike
Published: December 2007

Purpose

The purpose of this paper is to provide a review of the most recent literature concerning document supply and related matters.

Design/methodology/approach

The approach is based on the reading of over 150 journals as well as monographs, reports and web sites.

Findings

It was found that the fundamental debate on the direction of scholarly publishing continues intensely. Electronic books remain a minority market but some commentators suggest that screen readability has improved significantly. The mass digitisation of books continues apace. Open Access continues to grow but with widely differing views on its impact – the publishers fight back.

Originality/value

The paper represents a useful source of information for librarians and others interested in document supply and related matters.
Mary Jackson's musings 2
Authors: Jackson Mary E.
Published: December 2007

Purpose

The purpose of this paper is to provide an overview of resource‐sharing trends in the USA and internationally.

Design/methodology/approach

The article uses personal experience and views supported with background literature.

Findings

The article highlights recent developments in resource‐sharing standards, updated resource‐sharing statistics, describes new initiatives, and explores the implications of recent corporate mergers and product withdrawals.

Originality/value

The article provides a high level, and personal view of selected trends in North American resource sharing.
The importance of aggregators for libraries in the digital era
Authors: Galyani Moghaddam Golnessa , Moballeghi Mostafa
Published: December 2007

Purpose

The purpose of this paper is to define different types of aggregators and discuss their importance for libraries in the digital era.

Design/methodology/approach

A review of literature on aggregators was carried out. The paper focuses mainly on the various aggregators and outlines their advantages and disadvantages for libraries.

Findings

Libraries have been working with publishers and aggregators for many years; however, the issues related to aggregators are not well documented. Aggregators have been helping libraries to facilitate their services to users but they have some disadvantages for libraries such as the lack of library influence in selecting individual titles; the lack of control over the contents of aggregator packages; and the confusion of library users when accessing different packages.

Originality/value

The paper provides a useful overview to researchers in any field, enabling them to achieve quickly a clear picture of aggregators in the electronic environment.
Dynamic evolution in public‐private partnerships
Authors: Joyner Kate
Published: December 2007

Purpose

This paper seeks to examine the insights that the individual agency perspective offers to the study of public‐private partnerships (P3s). It extends prior research, which has primarily adopted an economic and structural perspective, by considering the ways by which individual actors involved in these complex arrangements can shape their evolutionary path.

Design/methodology/approach

This conceptual paper identifies the key research issues and questions in the P3 literature and highlights how these concerns can be further illuminated by the insights offered through the individual agency perspective.

Findings

The paper identifies four key issues in the P3 literature questions as the antecedents of P3s, pre‐formation processes, governance models and mechanisms, and evolution and adaptation. Introduction of the individual agency perspective to these research concerns highlights additional potentially explanatory factors for P3 formation and successful adaptation. The paper demonstrates that considering this perspective alongside current explanations can extend our current thinking and usefully add depth, breadth and linkage to P3 research.

Practical implications

This research challenges the current conceptions of P3 governance as one of choosing the appropriate structural option. It offers agency considerations at each stage in the sequence of P3 process and argues that individual capability and action can influence the success and effectiveness of these arrangements.

Originality/value

This research introduces a managerial perspective to the study of P3s and reframes the current thinking around governance of these forms. This contrasts with the more economic and structural agendas of public policy research.
The process of governance: through a practice lens
Authors: Smallman Clive
Published: December 2007

Purpose

The paper's purpose is to identify the inappropriateness of the current model of regulation of corporate governance, which applies worldwide; and inherent paradoxes in the five areas of best practice in corporate governance.

Design/methodology/approach

This is a review paper building new conceptualization for research into governance. The paper identifies the origins of the issues with weaknesses in the ontological and epistemological base for theorizing about corporate governance and its regulation. It suggests an alternative theoretical basis, identifying ways forward for developing theoretically aligned best practice along with regulation that properly reflects the complexity of the post‐modern business world.

Findings

The paper calls for a fresh approach to governance theorizing for regulation and best‐practice through considering governance praxis rather than structure and the reconceptualization of governance as a process of systematically balancing out tensions in order to effect good governance.

Practical implications

Governance research and regulation requires reframing so that good theory can improve practice.

Originality/value

The paper goes against the conventional wisdom in governance research, falling in with more advanced thinking for practice‐based studies of organising.
Web accessibility at Kentucky's academic libraries
Authors: Providenti Michael , Zai Robert
Published: December 2007

Purpose

The purpose of this paper is to provide an update on the implementation of web accessibility guidelines at Kentucky academic library web sites.

Design/methodology/approach

The academic library home pages of Bachelor‐degree granting institutions of Kentucky were tested for accessibility compliance using an online automated program. In addition, a series of manual accessibility tests were performed. Data were collected on errors against accessibility guidelines for each site. Data collected in 2003 were compared to data collected in 2007.

Findings

The number of library home pages complying with basic accessibility guidelines is increasing. However, most sites that score well are built to comply with checkpoints that can be tested automatically. Few institutions included accessibility features which required manual verification.

Research limitations/implications

This study relies largely on data collected with an imperfect accessibility‐checking software program. Some accessibility checkpoints can appear to be satisfied using automated accessibility tests despite the presence of accessibility barrier beings. Also, minor errors against accessibility guidelines are not distinguished from major accessibility barriers.

Practical implications

This study provides an impetus for web developers to aim higher than the automated accessibility checkpoints. It demonstrates a limited number of manual accessibility checkpoints that can be objectively tested.

Originality/value

This paper looks beyond accessibility guidelines that can be tested automatically to see if accessibility guidelines for which manual tests must be performed are being implemented. This study is one of the very few published follow‐up studies of web accessibility.
The evolution of paste pressure during stencil printing
Authors: Clements David J. , Desmulliez Marc P.Y. , Abraham Eitan
Published: December 2007

Purpose

The objective of this investigation is the derivation of a mathematical model that describes the pressure characteristics of paste during the stencil printing process. This model is intended to generalise a qualitative understanding of these effects using squeegees that can be curved but otherwise are standard in design.

Design/methodology/approach

This is an analytical treatment of the paste behaviour from the foundations of continuity of fluid flow and shear stresses that are imparted by the squeegee blade movement.

Findings

An equation is obtained that profiles the pressure generated by the squeegee movement which, for the case of a linear squeegee, shows very good agreement with predicted pressure profiles using experimental data.

Practical implications

This model provides a theoretical framework for a better understanding of how to overcome the failure modes inherent in stencil printing, such as over‐ or under‐filled stencil cavities.

Originality/value

This is a generalisation of a previously developed mesh printing model. It goes beyond flat squeegee designs to describe the printing process when the blade and stencil are in contact. In addition, it encompasses non‐Newtonian fluid behaviour.
The internet and international marketing
Authors: Alrawi K.
Published: December 2007

Purpose

This paper aims to provide a link between the concepts of internationalization and internetalization, since both have become an e‐business.

Design/methodology/approach

This study extends a model developed by Buttriss and Wilkinson which offers a starting‐point for classifying elements and identifying interactions in the internationalization process in global marketing. The objective has been achieved through the comparison between the Buttriss and Wilkinson model and a suggested model by the researcher.

Findings

The adoption of internationalization provides excellent opportunities in international marketing activities. It is suggested that e‐business is made up of many elements, such as business intelligence, supply chain management, customer relationship management, and enterprise resource planning. All of these existed in electronic form prior to the web but to a limited degree of penetration and below the level of sophistication that is prevailing today.

Originality/value

This paper fulfils and identifies resources needed and offers new thought to individuals in the field of management and probably IT.
Activity‐based life‐cycle costing in long‐range planning
Authors: Rodríguez Rivero Edilberto J. , Emblemsvåg Jan
Published: December 2007

Purpose

The aim of the paper is to present and illustrate a new approach for long‐range planning.

Design/methodology/approach

Building on well‐tested frameworks such as activity‐based costing (ABC), life‐cycle costing (LCC) and Monte Carlo methods as well as earlier case studies, an approach is developed further and tested using a real‐life case.

Findings

The effectiveness of the approach is confirmed using a process‐oriented framework (ABC) and introducing an LCC perspective. Monte Carlo methods are used to handle uncertainty and identify risks and critical success factors.

Research limitation/implications

The presented research is a starting‐point for developing a simple approach for budgeting that overcomes many of the problems with traditional budgeting.

Practical implications

The paper shows how long‐range planning can be performed in a realistic fashion without ending up in many of the traps of traditional budgeting.

Originality/value

The paper presents an approach that can help corporations anticipate the future much more realistically than before.
Alternative evidence on financial analysts' use of financial statement information
Authors: Byard Donal , Cebenoyan Fatma
Published: December 2007

Purpose

Financial analysts are frequently viewed as information intermediaries who process and interpret firms' financial reports for other market participants. Much recent research, however, has cast doubts on analysts' ability to fully utilize the information in firms' financial reports. Using an alternative approach, this study aims to provide evidence on how sophisticated analysts are at using information in firms' financial reports.

Design/methodology/approach

The paper estimates different measures of firms' operational efficiency, all of which are derived from financial statement data, and compares the strength of the association between these measures and analysts' absolute forecast errors. It then compares a sophisticated frontier‐based measure of firms' operational efficiency that evaluates firms' performance relative to their competitors with three more traditional efficiency measures; specifically the return on asset (ROA) ratio, industry‐adjusted ROA, and the return on equity ratio.

Findings

The results indicate that the more sophisticated frontier‐based measure is more strongly negatively associated with analysts' absolute forecast errors than the other three measures. The results thus suggest that analysts are capable of undertaking a sophisticated analysis of the information in firms' financial reports, at least as it pertains to operational efficiency.

Originality/value

To the extent that analysts serve as a key group of users of financial information, these results are likely to be of interest to accounting policy makers.
Shill‐bidding in private values auctions
Authors: Hlasny Vladimir
Published: December 2007

Purpose

The purpose of this paper is to present implications of the seller's ability to bid in the four classical auction forms, with independent private values: English, Dutch, first‐ and second‐price auctions.

Design/methodology/approach

Under each auction form, the identity of the winning bidder and the expected winning bid are compared between the case when the seller may bid and when he cannot, using equilibrium bidder strategies. The seller's incentive to bid is evaluated.

Findings

The strategies and the welfare results differ with auction type and underlying information assumptions – bidders are either aware or unaware of the seller's ability to bid. In the Dutch and the first‐price auctions, seller‐bidding does not affect any classical results. In the English and the second‐price auctions, it leads to no lower expected prices than without it and higher prices with positive probability. In the English and the second‐price auctions, the seller bids above his reservation value and may unintentionally win the auction. These auctions result in inefficiency with positive probability.

Practical implications

The English and the second‐price auctions are the most common real‐world auctions. In these auctions, the seller's ability to bid – secretly or publicly – redistributes welfare among participants and introduces a possibility of inefficiency. Making this ability publicly known does not solve the latter problem. Auctioneers must prevent the seller from bidding, or must select a different auction form when seller‐bidding is anticipated.

Originality/value

The paper clarifies to regulators, auction designers, bidders, and other readers which auction forms are susceptible to subversion by seller‐bidding and what the potential damages are.
MOS1 Osmosensor of
Metarhizium anisopliae
Is Required for Adaptation to Insect Host Hemolymph
Authors: Wang Chengshu , Duan Zhibing , St. Leger Raymond J.
Published: December 2007

Entomopathogenic fungi such as
Metarhizium anisopliae
infect insects by direct penetration of the cuticle, after which the fungus adapts to the high osmotic pressure of the hemolymph and multiplies. Here we characterize the
M. anisopliae Mos1
gene and demonstrate that it encodes the osmosensor required for this process. MOS1 contains transmembrane regions and a C-terminal Src homology 3 domain similar to those of yeast osmotic adaptor proteins, and homologs of MOS1 are widely distributed in the fungal kingdom. Reverse transcription-PCR demonstrated that
Mos1
is up-regulated in insect hemolymph as well as artificial media with high osmotic pressure. Transformants containing an antisense vector directed to the
Mos1
mRNA depleted transcript levels by 80%. This produced selective alterations in regulation of genes involved in hyphal body formation, cell membrane stiffness, and generation of intracellular turgor pressure, suggesting that these processes are mediated by MOS1. Consistent with a role in stress responses, transcript depletion of
Mos1
increased sensitivity to osmotic and oxidative stresses and to compounds that interfere with cell wall biosynthesis. It also disrupted developmental processes, including formation of appressoria and hyphal bodies. Insect bioassays confirmed that
Mos1
knockdown significantly reduces virulence. Overall, our data show that
M. anisopliae
MOS1 mediates cellular responses to high osmotic pressure and subsequent adaptations to colonize host hemolymph.
A Highly Conserved Protein of Unknown Function Is Required by
Sinorhizobium meliloti
for Symbiosis and Environmental Stress Protection
Authors: Davies Bryan W. , Walker Graham C.
Published: December 2007

We report here the first characterization of the
Sinorhizobium meliloti
open reading frame SMc01113. The SMc01113 protein is a member of a highly conserved protein family, universal among bacteria. We demonstrate that the SMc01113 gene is absolutely required for
S. meliloti
symbiosis with alfalfa and also for the protection of the bacterium from a wide range of environmental stresses.
Identification of Type 3 Fimbriae in UropathogenicEscherichia coliReveals a Role in Biofilm Formation
Authors: Ong Cheryl-Lynn Y. , Ulett Glen C. , Mabbett Amanda N. , Beatson Scott A. , Webb Richard I. , Monaghan Wayne , Nimmo Graeme R. , Looke David F. , McEwan Alastair G. , Schembri Mark A.
Published: December 2007

Catheter-associated urinary tract infection (CAUTI) is the most common nosocomial infection in the United States. UropathogenicEscherichia coli(UPEC), the most common cause of CAUTI, can form biofilms on indwelling catheters. Here, we identify and characterize novel factors that affect biofilm formation by UPEC strains that cause CAUTI. Sixty-five CAUTI UPEC isolates were characterized for phenotypic markers of urovirulence, including agglutination and biofilm formation. One isolate,E. coliMS2027, was uniquely proficient at biofilm growth despite the absence of adhesins known to promote this phenotype. Mini-Tn5mutagenesis ofE. coliMS2027 identified several mutants with altered biofilm growth. Mutants containing insertions in genes involved in O antigen synthesis (rmlCandmanB) and capsule synthesis (kpsM) possessed enhanced biofilm phenotypes. Three independent mutants deficient in biofilm growth contained an insertion in a gene locus homologous to the type 3 chaperone-usher class fimbrial genes ofKlebsiella pneumoniae. These type 3 fimbrial genes (mrkABCDF), which were located on a conjugative plasmid, were cloned fromE. coliMS2027 and could complement the biofilm-deficient transconjugants when reintroduced on a plasmid. Primers targeting themrkBchaperone-encoding gene revealed its presence in CAUTI strains ofCitrobacter koseri,Citrobacter freundii,Klebsiella pneumoniae, andKlebsiella oxytoca. All of thesemrkB-positive strains caused type 3 fimbria-specific agglutination of tannic acid-treated red blood cells. This is the first description of type 3 fimbriae inE. coli,C. koseri, andC. freundii. Our data suggest that type 3 fimbriae may contribute to biofilm formation by different gram-negative nosocomial pathogens.
Identification of Two Catalases in
Azotobacter vinelandii
: a KatG Homologue and a Novel Bacterial Cytochrome
c
Catalase, CCC

Av
Authors: Sandercock James R. , Page William J.
Published: December 2007

Azotobacter vinelandii
produces two detectable catalases during growth on minimal medium. The heat-labile catalase expressed during exponential growth phase was identified as a KatG homologue by liquid chromatography-tandem mass spectrometry (LC-MS/MS) using a mixed protein sample. The second catalase was heat resistant and had substantial residual activity after treatment at 90°C. This enzyme was purified by anion-exchange and size exclusion chromatography and was found to exhibit strong absorption at 407 nm, which is often indicative of associated heme moieties. The purified protein was fragmented by proteinase K and identified by LC-MS/MS. Some identity was shared with the MauG/bacterial cytochrome
c
peroxidase (BCCP) protein family, but the enzyme exhibited a strong catalase activity never before observed in this family. Because two putative
c
-type heme sites (CXXCH) were predicted in the peptide sequence and were demonstrated experimentally, the enzyme was designated a cytochrome
c
catalase (CCC

Av

). However, the local organization of the CCC

Av

heme motifs differed significantly from that of the BCCPs as the sites were confined to the C-terminal half of the catalase. A possible Ca
2+
binding motif, previously described in the BCCPs, is also present in the CCC

Av

peptide sequence. Some instability in the presence of EGTA was observed. Expression of the catalase was abolished in
cccA
mutants, resulting in a nearly 8,700-fold reduction in peroxide resistance in stationary phase.
Roles of the Major, Small, Acid-Soluble Spore Proteins and Spore-Specific and Universal DNA Repair Mechanisms in Resistance of
Bacillus subtilis
Spores to Ionizing Radiation from X Rays and High-Energy Charged-Particle Bombardment
Authors: Moeller Ralf , Setlow Peter , Horneck Gerda , Berger Thomas , Reitz Günther , Rettberg Petra , Doherty Aidan J. , Okayasu Ryuichi , Nicholson Wayne L.
Published: December 2007

The role of DNA repair by nonhomologous end joining (NHEJ), homologous recombination, spore photoproduct lyase, and DNA polymerase I and genome protection via α/β-type small, acid-soluble spore proteins (SASP) in
Bacillus subtilis
spore resistance to accelerated heavy ions (high-energy charged [HZE] particles) and X rays has been studied. Spores deficient in NHEJ and α/β-type SASP were significantly more sensitive to HZE particle bombardment and X-ray irradiation than were the
recA, polA
, and
splB
mutant and wild-type spores, indicating that NHEJ provides an efficient DNA double-strand break repair pathway during spore germination and that the loss of the α/β-type SASP leads to a significant radiosensitivity to ionizing radiation, suggesting the essential function of these spore proteins as protectants of spore DNA against ionizing radiation.
In vivo reactive oxygen species production induced by ischemia in muscle arterioles of mice: involvement of xanthine oxidase and mitochondria
Authors: Baudry Nathalie , Laemmel Elisabeth , Vicaut Eric
Published: December 2007

Reactive oxygen species (ROS) participate in tissue injury after ischemia-reperfusion. Their implication in leukocyte adherence and increase in permeability at the venular side of the microcirculation have been reported, but very little is known about ROS production in arterioles. The objective of this work was to evaluate, in the arteriole wall in vivo, the temporal changes in superoxide anion production during ischemia and reperfusion and to identify the source of this production. Mouse cremaster muscle was exposed to 1 h of ischemia followed by 30 min of reperfusion, and superoxide anion production was assessed by a fluorescent probe, i.e., intracellular dihydroethidium oxidation. During ischemia, we found a significant increase in dihydroethidium oxidation; however, we observed no additional increase in fluorescence during the subsequent reperfusion. This phenomenon was significantly inhibited by pretreatment with superoxide dismutase. Allopurinol (xanthine oxidase inhibitor) or stigmatellin [Qo-site (oriented toward the intermembrane space) inhibitor of mitochondrial complex III] or simultaneous administration of these two inhibitors significantly reduced superoxide production during ischemia to 80%, 88%, and 72%, respectively, of that measured in the untreated ischemia-reperfusion group. By contrast, no significant inhibition was found when NADPH oxidase was inhibited by apocynin or when mitochondrial complex I or complex II was inhibited by rotenone or thenoyltrifluoroacetone. A significant increase in ROS was found with antimycin A [Qi-site (located in the inner membrane and facing the mitochondrial matrix) inhibitor of mitochondrial complex III]. We conclude that a significant increase in ROS production occurs during ischemia in the arteriolar wall. This increased production involves both a cytoplasmic source (i.e., xanthine oxidase) and the mitochondrial complex III at the Qo site.
Astrocytes are a key conduit for upstream signaling of vasodilation during cerebral cortical neuronal activation in vivo
Authors: Xu Hao-Liang , Mao Lizhen , Ye Shuhua , Paisansathan Chanannait , Vetri Francesco , Pelligrino Dale A.
Published: December 2007

Astrocytes play an important role in the coupling between neuronal activity and brain blood flow via their capacity to “sense” neuronal activity and transmit that information to parenchymal arterioles. Here we show another role for astrocytes in neurovascular coupling: the ability to act as a signaling conduit for the vitally important process of upstream vasodilation (represented by pial arterioles) during both excessive (seizure) and physiological (sciatic nerve stimulation) increases in cerebral cortical neuronal activity. The predominance of an astrocytic rather than a vascular route was indicated by data showing that pial arteriolar-dilating responses to neuronal activation were completely blocked following selective disruption of the superficial glia limitans, whereas interference with interendothelial signaling was without effect. Results also revealed contributions from connexin 43, implying a role for gap junctions and/or hemichannels in the signaling process and that signaling from the glia limitans to pial arterioles may involve a diffusible mediator.
Peroxynitrite inhibits the expression of Giα protein and adenylyl cyclase signaling in vascular smooth muscle cells
Authors: Bassil Marcel , Li Yuan , Anand-Srivastava Madhu B.
Published: December 2007

We previously showed that S-nitroso- N-acetylpenicillamine, a nitric oxide donor, decreased the levels and functions of Giα proteins by formation of peroxynitrite (ONOO−) in vascular smooth muscle cells (VSMC). The present studies were undertaken to investigate whether ONOO−can modulate the expression of Giα protein and associated adenylyl cyclase signaling in VSMC. Treatment of A-10 and aortic VSMC with ONOO−for 24 h decreased the expression of Giα-2 and Giα-3, but not Gsα, protein in a concentration-dependent manner; expression was restored toward control levels by111Mn-tetralis(benzoic acid porphyrin) and uric acid, but not by 1 H[1,2,4]oxadiazole[4,3-a]quinoxaline-1-one (ODQ) and KT-5823. cGMP levels were increased by ∼50% and 150% by 0.1 and 0.5 mM ONOO−, respectively, and attenuated toward control levels by ODQ. In addition, 0.5 mM ONOO−attenuated the inhibition of adenylyl cyclase by ANG II and C-type atrial natriuretic peptide (C-ANP4–23), as well as the inhibition of forskolin-stimulated adenylyl cyclase activity by GTPγS, whereas, the Gs-mediated stimulations were augmented. In addition, 0.5 mM ONOO−decreased phosphorylation of ERK1/2 and p38 MAP kinase and enhanced JNK phosphorylation but did not affect AKT1/3 phosphorylation. These results suggest that ONOO−decreased the expression of Giproteins and associated functions in VSMC through a cGMP-independent mechanism and may involve the MAP kinase signaling pathway.
Pathophysiology of hypertension during preeclampsia: linking placental ischemia with endothelial dysfunction
Authors: Gilbert Jeffrey S. , Ryan Michael J. , LaMarca Babbette B. , Sedeek Mona , Murphy Sydney R. , Granger Joey P.
Published: December 2007

Studies over the last decade have provided exciting new insights into potential mechanisms underlying the pathogenesis of preeclampsia. The initiating event in preeclampsia is generally regarded to be placental ischemia/hypoxia, which in turn results in the elaboration of a variety of factors from the placenta that generates profound effects on the cardiovascular system. This host of molecules includes factors such as soluble fms-like tyrosine kinase-1, the angiotensin II type 1 receptor autoantibody, and cytokines such as tumor necrosis factor-α, which generate widespread dysfunction of the maternal vascular endothelium. This dysfunction manifests as enhanced formation of factors such as endothelin, reactive oxygen species, and augmented vascular sensitivity to angiotensin II. Alternatively, the preeclampsia syndrome may also be evidenced as decreased formation of vasodilators such as nitric oxide and prostacyclin. Taken together, these alterations cause hypertension by impairing renal pressure natriuresis and increasing total peripheral resistance. Moreover, the quantitative importance of the various endothelial and humoral factors that mediate vasoconstriction and elevation of arterial pressure during preeclampsia remains to be elucidated. Thus identifying the connection between placental ischemia/hypoxia and maternal cardiovascular abnormalities in hopes of revealing potential therapeutic regimens remains an important area of investigation and will be the focus of this review.