bluuebunny/crossref_metadata_2025 huggingface dataset:
Hindering factors of beginning teachers' high performance in higher education Pakistan
Authors: Sarwar Shakeel , Danyal Aslam Hassan , Imran Rasheed Muhammad
Published: January 2012

Purpose

The aim of the researchers in this endeavor is to identify the challenges and obstacles faced by beginning teachers in higher education. This study also explores practical implications and what adaptation can be utilized in order to have high performance of the beginning teachers.

Design/methodology/approach

Researchers have applied qualitative and quantitative technique to collect and interpret data. Semi‐structured interviews were conducted from the 40 beginning teachers of the case study university in order to identify various hindering factors of high performance.

Findings

Research results indicate that by addressing the 11 major hindering factors of beginning teachers' high performance, i.e. less teaching exposure, overburden, strict evaluation, lack of training, insufficient material and supplies, lack of effective communication, student counseling problems, classroom discipline problems, difficulties in assessing students' work, least expectations of career in teaching and misbehavior of students, the performance level of beginning teachers in higher education can be enhanced.

Originality/value

The current research addresses the most neglected area about teachers' performance management, that is problems of higher education teachers in their early careers. This exploration of beginning teachers' hindering issues can play a vital role in developing human resource development strategies in universities. The present research can prove to be a significant initiator for beginning teachers as they will get a glimpse of what problem areas they could face.
Factors affecting the implementation of curriculum reform in Hong Kong
Authors: Cheung Alan C.K. , Man Wong Ping
Published: January 2012

Purpose

The objective of this paper was to examine key hindering and facilitating factors in schools during the first stage of the curriculum reform (2001‐2006) in Hong Kong and to identify key strategies to address these challenges.

Design/methodology/approach

A total of 150 primary and 120 secondary schools with 7,869 key stakeholders including principals, curriculum leaders, teachers, and students participated in the study. The data for this study was collected from the following two major methods: survey questionnaire and in‐depth interviews. The response rate was 95 percent.

Findings

In spite of the different roles played by each stakeholder in the curriculum reform, the perceptions of school principals, curriculum leaders, and teachers were very similar with regards to the factors that facilitated and hindered their successful implementation of the reform. Consistent with the current literature, the findings clearly indicated that the recent curriculum reform in Hong Kong was still facing several key obstacles and challenges that were common in many other countries, in the implementation stage, such as teachers' heavy workloads, learning diversity in class, and teachers' inadequate understanding of the reform.

Originality/value

The study is important in that this was the first large‐scale study ever conducted to examine the progress of the recent curriculum reform in Hong Kong. The findings of the results generate important policy recommendations that may improve the implementation of the curriculum reform in the next phase and contribute to the related literature in the areas of curriculum reform not only in Hong Kong but also other parts of the world.
A level playing field: social inclusion in public leisure
Authors: Hodgkinson Ian R. , Hughes Paul
Published: January 2012

Purpose

The transfer to partnership in public sector management has created significantly new modes of service delivery, and is suggested to be the best means of ensuring that disadvantaged groups are socially included. The purpose of this paper is to examine New Leisure Trust (NLT) structures in public leisure provision relative to direct, in‐house managed facilities and privately run Leisure Management Contractor (LMC) facilities. In particular, NLTs receive significant government funds and subsidies through tax breaks that are not forthcoming to rivals, which raises questions as to whether NLTs deserve such aid for delivering upon the social inclusion agenda of the government.

Design/methodology/approach

The research involved a national survey questionnaire to 1,060 public leisure service providers in England. Empirical testing through multiple analysis of variance and regression analysis was applied to the dataset.

Findings

The authors find that NLTs do not follow social orientation strategies to any significantly greater degree than rivals, nor seem to create social inclusion to any greater degree. Further, NLTs have the least to gain in terms of business performance from creating social inclusion, whilst in‐house (in particular) and LMC facilities stand to gain the most.

Practical implications

Though each approach to provision examined places a considerable strategic emphasis on being socially oriented, they are not effective at increasing the social inclusion of recreationally disadvantaged groups.

Originality/value

This paper calls for the current public leisure management playing field to be levelled in a rebalance of opportunity and investment through the removal of anti‐competitive measures.
Initial emergency response performance of fire fighters in Malaysia
Authors: Subramaniam Chandrakantan , Ali Hassan , Mohd Shamsudin Faridahwati
Published: January 2012

Purpose

The purpose of this paper is to identify the initial emergency response time of fire fighting teams in Malaysia.

Design/methodology/approach

In an emergency incident time is of the essence, and the basic philosophy of an emergency response agency is to respond as quickly as possible to minimize the loss of life and property damage. In the current study, emergency response performance refers to team members' speed in responding to emergency situations, which was measured as the time taken for the team members to get to the fire truck from the waiting room in selected fire stations in Malaysia. The data collection period lasted for five months.

Findings

This study found that the overall average initial emergency response time was 84 seconds, while the overall average weighted initial emergency response time was 3.71 seconds per meter. The current study has demonstrated that the average initial emergency response performed by fire fighting teams in Malaysia is apparently better than that reported by previous studies by other emergency responders.

Originality/value

This paper presents empirical evidence of the initial emergency response time of fire fighters in Malaysia, by taking into account the distance traveled by the responders. As such, the performance measure obtained gives a meaningful indicator. The finding of the current study is then compared to emergency response performance by other emergency response agencies in other countries.
The effects and interactions of fabrication parameters on the properties of selective laser sintered hydroxyapatite polyamide composite biomaterials
Authors: Savalani M.M. , Hao L. , Dickens P.M. , Zhang Y. , Tanner K.E. , Harris R.A.
Published: January 2012

Purpose

Hydroxyapatite‐polymer composite materials are being researched for the development of low‐load bearing implants because of their bioactive and osteoconductive properties, while avoiding modulus mismatch found in homogenous materials. For the direct production of hydroxyapatite‐polymer composite implants, selective laser sintering (SLS) has been used and various parameters and their effects on the physical properties (micro and macro morphologies) have been investigated. The purpose of this paper is to identify the most influential parameters on the micro and macro pore morphologies of sintered hydroxyapatite‐polymer composites.

Design/methodology/approach

A two‐level full factorial experiment was designed to evaluate the effects of the various processing parameters and their effects on the physical properties, including open porosity, average pore width and the percentage of pores which could enable potential bone regeneration and ingrowth of the sintered parts. The density of the sintered parts was measured by weight and volume; optical microscopy combined with the interception method was used to determine the average pore size and proportion of pores suitable to enable bone regeneration.

Findings

It was found that the effect of build layer thickness was the most influential parameter with respect to physical and pore morphology features. Consequently, it is found that the energy density equation with the layer thickness parameter provides a better estimation of part porosity of composite structures than the energy density equation without the layer thickness parameter. However, further work needs to be conducted to overcome the existing error of variance.

Originality/value

This work is the first step in identifying the most significant SLS parameters and their effects on the porosity, micro and macro pore morphologies of the fabricated parts. This is an important step in the further development of implants which may be required.
Statistical modeling and minimization of form error in SLS prototyping
Authors: Senthilkumaran K. , Pandey P.M. , Rao P.V.M.
Published: January 2012

Purpose

The purpose of this paper is to report experimental investigations performed to analyze the effect of process parameters on the shape accuracy of selective laser sintered (SLS) parts.

Design/methodology/approach

The effect of process parameters, namely build orientation, laser power, scan speed, cylinder diameter and build chamber temperature has been studied on shape accuracy by using geometric tolerances such as cylindricity and flatness. Central composite design (CCD) is used to plan the experiments and a second order regression model has been developed to predict flatness and cylindricity. The significance of process variables on flatness and cylindricity has been evaluated using analysis of variance technique.

Findings

It is observed that interaction effects are more dominant than individual effects. In case of cylindricity, it is found that the interaction between the scan speed and orientation is the dominant factor next to the orientation and quadratic effect of the geometry. In case of flatness, the interaction between build chamber temperature and scan speed is the dominant factor.

Research limitations/implications

The empirical models presented in this paper work within the range of values used for the experiments and most of these models need to be redeveloped for use with other materials.

Practical implications

The empirical models developed in this work would be useful in deciding the process parameters for parts with improved geometrical tolerances. The optimum parameters identified from the empirical model are found to yield accurate parts with minimum shape error.

Originality/value

The paper establishes the interactions between this build orientation, geometry and process parameters on the shape accuracy of SLS process.
Work experience and the generation of new business ideas among entrepreneurs
Authors: Gabrielsson Jonas , Politis Diamanto
Published: January 2012

Purpose

This paper seeks to develop an integrated framework to examine how entrepreneurs' work experience is associated with the generation of new business ideas. The framework combines human capital theory with theory and research on entrepreneurial learning.

Design/methodology/approach

A statistical analysis on a sample of 291 Swedish entrepreneurs is conducted.

Findings

The paper finds that a learning mind‐set that favors exploration is the strongest predictor of the generation of new business ideas. It also finds that breadth in functional work experience seems to favor the generation of new business ideas while deep industry work experience is negatively related to new business idea generation. In addition, the paper finds indications that a learning mind‐set that favors exploration is required to more fully benefit from investments in human capital.

Research limitations/implications

The study's findings add to knowledge of how investments in human capital via work experience, and the employment of a learning mindset that favors exploration, influence performance outcomes in the early stages of the entrepreneurial process.

Practical implications

The study's findings suggest that entrepreneurs should develop and nurture a learning mind‐set that favors exploration as this will increase their ability to generate more new business ideas. Moreover, movements across different functional work areas appear to have great potential as sources of ideas for new products and markets.

Originality/value

Prior empirical studies have not taken individual learning preferences among entrepreneurs into account. Nor have they explicitly tested the effect of depth versus breadth in work experience. The paper thus provides novel insights with respect to how these factors interact in the process of generating new business ideas.
Mental health service user involvement in policy development: social inclusion or disempowerment?
Authors: Cowan Sue , Banks David , Crawshaw Paul , Clifton Andrew
Published: January 2012

Purpose

The paper's purpose is to reopen a debate around the potential impact of narrow conceptualisations of inclusion, or participation, of service users in current mental health policy development and implementation.

Design/methodology/approach

The approach here is a conceptual analysis of the continuity of “‘New Labour’ thinking” and its connection to Putnam on social capital and citizenship, whilst also offering counter critiques drawing on Bourdieu, Rose, and Arnstein.

Findings

The findings show the potential for disempowerment and argue for alternative service user action, either contracting on “their own rules of engagement” or specifically taking up an oppositional stance to disempowering forms of involvement. The authors also draw attention to the influence of differing English and Scottish policy drivers which appear to offer potentially different forms of engagement.

Originality/value

The paper offers a fresh analysis that particularly points to the potential value of service user groups considering alternative forms of involvement, rather than those prescribed by “Third Way” or “Big Society” thinking.
The adoption of open innovation within the telecommunication industry
Authors: Bigliardi Barbara , Ivo Dormio Alberto , Galati Francesco
Published: January 2012

Purpose

The paper, covering the actual argument of open innovation, aims to answer two main research questions, namely: “Which open innovation approach is adopted by the companies belonging to the ICTs industry?” and “Which types of collaborations are carried out by the companies and which are the dynamics that characterize it?”.

Design/methodology/approach

In order to answer the research questions a multiple case study methodology is adopted. The research framework was structured in three main phases: first, a literature review on the matter of open innovation in general and within the ICTs industry in particular, as well as of the specific features of the industry investigated, was carried out. Second, a list of questions containing the main issues that arose from the previous step has been designed for the case study protocol, to be used in the following structured interviews. Finally, structured direct interviews were conducted on three important Italian companies active in the telecommunications area.

Findings

Results highlighted different ways to manage the open innovation processes, based on teamwork or task forces, and the different roles, more or less proactive, that an information communication technology (ICT) company may undertake within this process. Moreover, they show that ICT companies acquire external knowledge and skills mainly from universities and research centers, as well as from value chain's actors (suppliersin primis).

Originality/value

Still little attention has been paid to the understanding of the open innovation approach of Italian firms belonging to the ICT industry, thus the authors believe that this paper may represent a valuable basis for future research on the open innovation issues in the field of ICT.
Evolution of project teams for Generation Y workforce
Authors: Anantatmula Vittal S. , Shrivastav Bobbie
Published: January 2012

Purpose

The purpose of this paper is to develop a knowledge base for project managers to understand and deal with issues that arise out of Generation Y working with other generations. The research study is expected to generate interest among the research community for undertaking similar studies to advance understanding on this interesting and important topic.

Design/methodology/approach

This research method consists of analyzing literature review findings and survey results of an exploratory study of Generation Y working professionals. Both the literature review findings and the study results were analyzed to develop findings and recommendations.

Findings

Research results confirmed that the generation gap is an issue. Generation Y is viewed unfavorably and they face struggles in dealing with other generations. These generation gap issues might vary depending on the type of industry and composition of the workforce. People from each generation – raised in different social and technological contexts – bring different attitudes, values, and work ethics to the workplace and a project manager is required to manage these to improve project team effectiveness.

Research limitations/implications

The research study has a participant selection bias; only Gen Y working professionals from the USA participated in the study and people from other generations and Generation Y people from other countries were not included in the study. Therefore, study results do not reflect issues from the perspectives of other generations. A similar study that considers participation of people from real project teams consisting of different generations is recommended to validate the research results of this study.

Practical implications

The paper explored issues concerning project teams consisting of members from different generations. Results are expected to help project managers develop team management strategies. This study is also aimed to develop a foundation for future studies to examine how project management can deal with project teams consisting of people of different generations working together. The study findings and implications for practical use are limited due to participation bias.

Originality/value

The study is an original effort in examining some of the issues related to different generations working together in a project environment. Results are of relevance in today's corporate world. Project teams span many generations and present challenges in developing them into a high performing team. This paper addresses some of the challenges from the perspective of Generation Y.
Understanding PMs' activities in a coopetitive interorganizational multi‐project setting
Authors: Burström Thommie
Published: January 2012

Purpose

The purpose of this paper is to understand the character of activities performed by project managers (PMs) in the early phases of product development in an interorganizational, multi‐project setting. The aim is to contribute to the extant literature on boundary work in projects by providing a typology of boundary activities and by presenting a conceptual model in which the relationship between these boundary activities is established.

Design/methodology/approach

This study is based on an explorative, in‐depth case study of a multi‐project setting where PMs assigned to three projects developed new products while simultaneously competing and collaborating. Each project's concept phase was followed by participative observations and ongoing interviews over a 15‐week period at two sites and in two countries.

Findings

It is understood that PMs in organizations collaborate and perform balancing activities. These balancing activities are part of a refinement process, which is created through three intertwined dimensions of boundary activities: administrative, sharing, and tuning. These, in turn, are constructed through complementary micro activities. These micro activities are politically colored and do not necessarily follow a prescribed and orderly path; instead, they are situation contingent and iterative in their character.

Research limitations/implications

The character of boundary activities in coopetitive project settings should be further studied to better understand the early phases of product development.

Practical implications

The political dimension of product development activities in the early phases of product development should be acknowledged. By acknowledging the presence of politics, PMs will be more prepared to deal with the complexity and ambiguity that follows when trying to collaborate and compete simultaneously.

Originality/value

This paper takes a practice perspective and focuses on what people do in interorganizational new product development in situations characterised by coopetition.
Redesigning a project‐oriented organization in a complex system
Authors: Staadt Jürgen
Published: January 2012

Purpose

The purpose of this paper is to demonstrate the usability of systems thinking in the process of redesigning a leading public housing provider within a problematic situation. The paper attempts to describe the influence of evolving negative internal socio‐political arrangements on the further development of the whole organization and suggests a purposeful activity model based on constant improvement and collaborative learning for the ongoing intervention.

Design/methodology/approach

The study combines soft systems methodology, as the leading or guiding methodology, with case study research and action research. This rather pluralistic approach made it possible to adequately respond to the varying tasks and intricacies of the different research phases within a power‐laden environment. Each phase or part of the process was informed by the analysis of the preceding one, thus creating a documented learning process.

Findings

The results reveal that further development within the project‐oriented organization was hindered or blocked by failure to address the oppressive socio‐political system. The proposed new design, based on systems thinking, allocates an important role to project management and its ability to cope with different paradigms and to address tame, messy as well as wicked problems. Consequently, the discipline of project management should further develop towards an equal appreciation of hard as well as soft systems thinking which emphasises a critical systems thinking approach.

Practical implications

The project management capabilities needed in the complex housing system go beyond the strategic and operational level since a greater understanding of complex social systems as well as their behaviour is of major importance. This puts emphasis on problem structuring methods and methodologies, as well as their combination, so as to support the debate about the nature of organizational as well as societal problems rather than to focus on their solution.

Originality/value

The paper describes the first soft systems methodology intervention in a predominantly francophone country within the European Union. It proposes a new avenue to the management of organizational as well as societal problems.
Economic Reform and Total Factor Productivity Growth in Indian Manufacturing Industries
Authors: Kim Sangho , Saravanakumar Muthusamy
Published: January 2012

A stochastic frontier production function model is applied to Indian manufacturing industries, to decompose the sources of total factor productivity growth into technical progress, technical efficiency, scale efficiency, and allocative efficiency. Empirical results based on data from 2000 to 2006 suggest that increased investment needs time to deliver increased productivity and efficiency, because new technology combined with fresh investment requires higher numbers of skilled workers, better managerial practices and an advanced input mix, all of which generally take time to develop. Thus, the Indian economy must boost technical efficiency by providing skilled workers and high quality managers to further economic reform.
Neuraminidase H275Y and hemagglutinin D222G mutations in a fatal case of 2009 pandemic influenza A (H1N1) virus infection
Authors: DeVries Aaron , Wotton Jason , Lees Christine , Boxrud David , Uyeki Timothy , Lynfield Ruth
Published: January 2012

Please cite this paper as: DeVries et al. (2012) Neuraminidase H275Y and hemagglutinin D222G mutations in a fatal case of 2009 pandemic influenza A (H1N1) virus infection. Influenza and Other Respiratory Viruses 6(601), e85–e88.

Oseltamivir‐resistant 2009 H1N1 influenza virus infections associated with neuraminidase (NA) H275Y have been identified sporadically. Strains possessing the hemagglutinin (HA) D222G mutation have been detected in small numbers of fatal 2009 H1N1 cases. We report the first clinical description of 2009 H1N1 virus infection with both NA‐H275Y and HA‐D222G mutations detected by pyrosequencing of bronchioalveolar lavage fluid obtained on symptom day 19. The 59‐year‐old immunosuppressed patient had multiple conditions conferring higher risk of prolonged viral replication and severe illness and died on symptom day 34. Further investigations are needed to determine the significance of infection with strains possessing NA‐H275Y and HA‐D222G.
Neural regulation of inflammation: no neural connection from the vagus to splenic sympathetic neurons
Authors: Bratton B. O. , Martelli D. , McKinley M. J. , Trevaks D. , Anderson C. R. , McAllen R. M.
Published: January 2012

The ‘inflammatory reflex’ acts through efferent neural connections from the central nervous system to lymphoid organs, particularly the spleen, that suppress the production of inflammatory cytokines. Stimulation of the efferent vagus has been shown to suppress inflammation in a manner dependent on the spleen and splenic nerves. The vagus does not innervate the spleen, so a synaptic connection from vagal preganglionic neurons to splenic sympathetic postganglionic neurons was suggested. We tested this idea in rats. In a preparatory operation, the anterograde tracer DiI was injected bilaterally into the dorsal motor nucleus of vagus and the retrograde tracer Fast Blue was injected into the spleen. On histological analysis 7–9 weeks later, 883 neurons were retrogradely labelled from the spleen with Fast Blue as follows: 89% in the suprarenal ganglia (65% left, 24% right); 11% in the left coeliac ganglion; but none in the right coeliac or either of the superior mesenteric ganglia. Vagal terminals anterogradely labelled with DiI were common in the coeliac but sparse in the suprarenal ganglia, and confocal analysis revealed no putative synaptic connection with any Fast Blue‐labelled cell in either ganglion. Electrophysiological experiments in anaesthetized rats revealed no effect of vagal efferent stimulation on splenic nerve activity or on that of 15 single splenic‐projecting neurons recorded in the suprarenal ganglion. Together, these findings indicate that vagal efferent neurons in the rat neither synapse with splenic sympathetic neurons nor drive their ongoing activity.
Magnetic Nanotubes Influence the Response of Dorsal Root Ganglion Neurons to Alternating Magnetic Fields
Authors: Xie Jining , Chen Linfeng , Varadan Vijay K. , Chetan Sahitya , Srivatsan Malathi
Published: January 2012

Magnetic nanotubes hold the potential for neuroscience applications because of the feasibility of controlling the orientation or movement of magnetic nanotubes and their ability to deliver chemicals or biomolecules by an external magnetic field, which can facilitate directed growth of neurites. Therefore, we sought to investigate the effects of laminin treated magnetic nanotubes and external alternating magnetic fields on the growth of dorsal root ganglion (DRG) neurons in cell culture. Magnetic nanotubes were synthesized by a hydrothermal method and characterized to confirm their hollow structure, the hematite and maghemite phases, and the magnetic properties. DRG neurons were cultured in the presence of laminin coupled magnetic nanotubes under alternating magnetic fields. Electron microscopy showed a close interaction between magnetic nanotubes and the growing neurites. Phase contrast microscopy revealed live growing neurons suggesting that the combination of the presence of magnetic nanotubes and the alternating magnetic field were tolerated by DRG neurons. The synergistic effects, from both laminin treated magnetic nanotubes and the applied magnetic field on the survival, growth, and electrical activities of the DRG neurons, are currently being investigated.
The Impact of the Bauschinger Effect on Stress Concentrations and Stress Intensity Factors for Eroded Autofrettaged Thick Cylindrical Pressure Vessels
Authors: Ma Q. , Levy C. , Perl M.
Published: January 2012

Our previous studies have shown that stress intensity factors (SIFs) are influenced considerably from the presence of the Bauschinger Effect (BE) in thick-walled pressurized cracked cylinders. For some types of pressure vessels, such as gun barrels, working in corrosive environment, in addition to acute temperature gradients and repetitive high-pressure impulses, erosions can be practically induced. Those erosions cause stress concentration at the bore, where cracks can readily initiate and propagate. In this study, the BE on the SIFs will be investigated for a crack emanating from an erosion’s deepest point in a multiply eroded autofrettaged, pressurized thick-walled cylinder. A commercial finite element package, ansys, was employed to perform this type of analysis. A two-dimensional model, analogous to the authors’ previous studies, has been adopted for this new investigation. Autofrettage with and without BE, based on von Mises yield criterion, is simulated by thermal loading and the SIFs are determined by the nodal displacement method. The SIFs are evaluated for a variety of relative crack lengths, a0/t = 0.01–0.45 emanating from the tip of the erosion of different geometries including (a) semicircular erosions of relative depths of 1%–10% of the cylinder’s wall thickness, t; (b) arc erosions for several dimensionless radii of curvature, r′/t = 0.05–0.4; and (c) semi-elliptical erosions with ellipticities of d/h = 0.5–1.5, and erosion span angle, α, from 6 deg to 360 deg. The effective SIFs for relatively short cracks are found to be increased by the presence of the erosion and further increased due to the BE, which may result in a significant decrease in the vessel’s fatigue life. Deep cracks are found to be almost unaffected by the erosion, but are considerably affected by BE.
Occurrence and Persistence of Bacterial Pathogens and Indicator Organisms in Beach Sand along the California Coast
Authors: Yamahara Kevan M. , Sassoubre Lauren M. , Goodwin Kelly D. , Boehm Alexandria B.
Published: January 2012

This report documents the presence of fecal indicators and bacterial pathogens in sand at 53 California marine beaches using both culture-dependent and -independent (PCR and quantitative PCR [QPCR]) methods. Fecal indicator bacteria were widespread in California beach sand, withEscherichia coliand enterococci detected at 68% and 94% of the beaches surveyed, respectively. Somatic coliphages and aBacteroidaleshuman-specific fecal marker were detected at 43% and 13% of the beaches, respectively. Dry sand samples from almost 30% of the beaches contained at least one of the following pathogens:Salmonellaspp.,Campylobacterspp.,Staphylococcus aureus, and methicillin-resistantStaphylococcus aureus(MRSA), which were detected at 15%, 13%, 14%, and 3% of tested beaches, respectively. Fecal indicators and pathogens were poorly correlated to one another and to land cover. Sands were dry at the time of collection, and those with relatively high moisture tended to have higher concentrations or a more frequent occurrence of both indicators and pathogens. Using culture-dependent assays, fecal indicators decayed faster than pathogens in microcosm experiments using unaltered beach sand seeded with sewage and assessed by culture-dependent assays. The following order of persistence was observed (listed from most to least persistent):Campylobacter>Salmonella> somatic coliphages > enterococci >E. coli> F+phages. In contrast, pathogens decayed faster than fecal indicators in culture-independent assays: enterococci >Bacteroidaleshuman-specific marker >Salmonella>Campylobacter. Microcosm experiments demonstrated that both indicators and pathogens were mobilized by wetting with seawater. Decay rates measured by QPCR were lower than those measured with culture-dependent methods. Enterococcal persistence and possible growth were observed for wetted microcosms relative to unwetted controls.
Unexpected Stability of Bacteroidetes and Firmicutes Communities in Laboratory Biogas Reactors Fed with Different Defined Substrates
Authors: Kampmann K. , Ratering S. , Kramer I. , Schmidt M. , Zerr W. , Schnell S.
Published: January 2012

In the present study, bacterial communities in 200-liter biogas reactors containing liquid manure consecutively fed with casein, starch, and cream were investigated over a period of up to 33 days. A 16S rRNA gene clone library identified
Bacteroidetes
and
Firmicutes
as the most abundant bacterial groups in the starting material, at 58.9% and 30.1% of sequences, respectively. The community development of both groups was monitored by real-time PCR and single-strand conformation polymorphism (SSCP) analysis. The
Firmicutes
and
Bacteroidetes
communities were unexpectedly stable and hardly influenced by batch-feeding events. The continuous feeding of starch led to community shifts that nevertheless contributed to a stable reactor performance. A longer starving period and a change in the pH value resulted in further community shifts within the
Bacteroidetes
but did not influence the
Firmicutes
. Predominant DNA bands from SSCP gels were cloned and sequenced. Sequences related to
Peptococcaceae
,
Cytophagales
, and
Petrimonas sulfuriphila
were found in all samples from all experiments. Real-time PCR demonstrated the abundance of members of the phylum
Bacteroidetes
and also reflected changes in gene copy numbers in conjunction with a changing pH value and acetate accumulation.
Influence of Anaerobiosis and Low Temperature on Bacillus cereus Growth, Metabolism, and Membrane Properties
Authors: de Sarrau Benoît , Clavel Thierry , Clerté Caroline , Carlin Frédéric , Giniès Christian , Nguyen-The Christophe
Published: January 2012

The impact of simultaneous anaerobiosis and low temperature on growth parameters, metabolism, and membrane properties of
Bacillus cereus
ATCC 14579 was studied. No growth was observed under anaerobiosis at 12°C. In bioreactors, growth rates and biomass production were drastically reduced by simultaneous anaerobiosis and low temperature (15°C). The two conditions had a synergistic effect on biomass reduction. In anaerobic cultures, fermentative metabolism was modified by low temperature, with a marked reduction in ethanol production leading to a lower ability to produce NAD
+
. Anaerobiosis reduced unsaturated fatty acids at both low optimal temperatures. In addition, simultaneous anaerobiosis and low temperatures markedly reduced levels of branched-chain fatty acids compared to all other conditions (accounting for 33% of total fatty acids against more 71% for low-temperature aerobiosis, optimal-temperature aerobiosis, and optimal-temperature anaerobiosis). This corresponded to high-melting-temperature lipids and to low-fluidity membranes, as indicated by differential scanning calorimetry, 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence anisotropy, and infrared spectroscopy. This is in contrast to requirements for cold adaptation. A link between modification in the synthesis of metabolites of fermentative metabolism and the reduction of branched-chain fatty acids at low temperature under anaerobiosis, through a modification of the oxidizing capacity, is assumed. This link may partly explain the impact of low temperature and anaerobiosis on membrane properties and growth performance.
A Novel Restriction-Modification System Is Responsible for Temperature-Dependent Phage Resistance in Listeria monocytogenes ECII
Authors: Kim Jae-Won , Dutta Vikrant , Elhanafi Driss , Lee Sangmi , Osborne Jason A. , Kathariou Sophia
Published: January 2012

Listeria monocytogenes
epidemic clone II (ECII) strains are unusual in being completely resistant to phage when grown at low temperatures (≤30°C). In the current study we constructed and characterized a
mariner
-based mutant (J46C) of the ECII strain H7550-Cd
S
that lacked temperature-dependent resistance to phage. The transposon was localized in LMOh7858_2753 (open reading frame [ORF] 2753), a member of a 12-ORF genomic island unique to ECII strains. ORF 2753 and ORF 2754 exhibited homologies to restriction endonucleases and methyltransferases associated with type II restriction-modification (RM) systems.
In silico
-based predictions of the recognition site for this putative RM system were supported by resistance of DNA from ECII strains to digestion by BfuI, a type II restriction enzyme specific for GTATCC (N6/5). Similarly to J46C, a mutant harboring an in-frame deletion of ORF 2753 was susceptible to phage regardless of temperature of growth (25°C or 37°C). Genetic complementation restored phage resistance in 25°C-grown cells of ORF 2753 mutants. Reverse transcription (RT) and quantitative real-time PCR data suggested enhanced transcription of ORF 2753 at low temperatures (≤25°C) compared to 37°C. In contrast, available transcriptional data suggested that the putative methyltransferase (ORF 2754) was constitutively expressed at all tested temperatures (4 to 37°C). Thus, temperature-dependent resistance of
L. monocytogenes
ECII to phage is mediated by temperature-dependent expression of the restriction endonuclease associated with a novel RM system (LmoH7) unique to this epidemic clone.
Extensive Manipulation of Caseicins A and B Highlights the Tolerance of These Antimicrobial Peptides to Change
Authors: Norberg Sarah , O'Connor Paula M. , Stanton Catherine , Ross R. Paul , Hill Colin , Fitzgerald Gerald F. , Cotter Paul D.
Published: January 2012

Caseicins A and B are low-molecular-weight antimicrobial peptides which are released by proteolytic digestion of sodium caseinate. Caseicin A (IKHQGLPQE) is a nine-amino-acid cationic peptide, and caseicin B (VLNENLLR) is a neutral eight-amino-acid peptide; both have previously been shown to exhibit antibacterial activity against a number of pathogens, including
Cronobacter sakazakii
. Previously, four variants of each caseicin which differed subtly from their natural counterparts were generated by peptide synthesis. Antimicrobial activity assays revealed that the importance of a number of the residues within the peptides was dependent on the strain being targeted. In this study, this engineering-based approach was expanded through the creation of a larger collection of 26 peptides which are altered in a variety of ways. The investigation highlights the generally greater tolerance of caseicin B to change, the fact that changes have a more detrimental impact on anti-Gram-negative activity, and the surprising number of variants which exhibit enhanced activity against
Staphylococcus aureus
.
Detection of Coxiella burnetii DNA on Small-Ruminant Farms during a Q Fever Outbreak in the Netherlands
Authors: de Bruin A. , van der Plaats R. Q. J. , de Heer L. , Paauwe R. , Schimmer B. , Vellema P. , van Rotterdam B. J. , van Duynhoven Y. T. H. P.
Published: January 2012

During large Q fever outbreaks in the Netherlands between 2007 and 2010, dairy goat farms were implicated as the primary source of human Q fever. The transmission of
Coxiella burnetii
to humans is thought to occur primarily via aerosols, although available data on
C. burnetii
in aerosols and other environmental matrices are limited. During the outbreak of 2009, 19 dairy goat farms and one dairy sheep farm were selected nationwide to investigate the presence of
C. burnetii
DNA in vaginal swabs, manure, surface area swabs, milk unit filters, and aerosols. Four of these farms had a positive status during the
Coxiella burnetii
bulk milk monitoring program in 2009 and additionally reported abortion waves in 2008 or 2009. Eleven farms were reported as having positive bulk milk only, and five selected (control) farms had a bulk milk-negative status in 2009 and no reported Q fever history. Screening by quantitative PCR (qPCR) revealed that on farms with a history of abortions related to
C. burnetii
and, to a lesser extent, on farms positive by bulk milk monitoring, generally higher proportions of positive samples and higher levels of
C. burnetii
DNA within positive samples were observed than on the control farms. The relatively high levels of
C. burnetii
DNA in surface area swabs and aerosols sampled in stables of bulk milk-positive farms, including farms with a Q fever-related abortion history, support the hypothesis that these farms can pose a risk for the transmission of
C. burnetii
to humans.
The Ustilago maydis Nit2 Homolog Regulates Nitrogen Utilization and Is Required for Efficient Induction of Filamentous Growth
Authors: Horst Robin J. , Zeh Christine , Saur Alexandra , Sonnewald Sophia , Sonnewald Uwe , Voll Lars M.
Published: January 2012

Nitrogen catabolite repression (NCR) is a regulatory strategy found in microorganisms that restricts the utilization of complex and unfavored nitrogen sources in the presence of favored nitrogen sources. In fungi, this concept has been best studied in yeasts and filamentous ascomycetes, where the GATA transcription factors Gln3p and Gat1p (in yeasts) and Nit2/AreA (in ascomycetes) constitute the main positive regulators of NCR. The reason why functional Nit2 homologs of some phytopathogenic fungi are required for full virulence in their hosts has remained elusive. We have identified the Nit2 homolog in the basidiomycetous phytopathogen
Ustilago maydis
and show that it is a major, but not the exclusive, positive regulator of nitrogen utilization. By transcriptome analysis of sporidia grown on artificial media devoid of favored nitrogen sources, we show that only a subset of nitrogen-responsive genes are regulated by Nit2, including the Gal4-like transcription factor Ton1 (a target of Nit2). Ustilagic acid biosynthesis is not under the control of Nit2, while nitrogen starvation-induced filamentous growth is largely dependent on functional Nit2.
nit2
deletion mutants show the delayed initiation of filamentous growth on maize leaves and exhibit strongly compromised virulence, demonstrating that Nit2 is required to efficiently initiate the pathogenicity program of
U. maydis
.
Assessment and prevention of exercise-induced bronchoconstriction
Authors: Anderson Sandra D , Kippelen Pascale
Published: January 2012

The assessment of exercise-induced bronchoconstriction (EIB) in athletes requires the measurement of forced expiratory volume in 1 s (FEV1) before and after vigorous exercise or a surrogate of exercise such as eucapnic voluntary hyperpnoea (EVH) of dry air or mannitol dry powder. Exercise testing in a laboratory has a low sensitivity to identify EIB, and exercise testing in the field can be a challenge in itself particularly in cold weather athletes. The EVH test requires the subject to ventilate dry air containing ∼5% CO2for 6 min through a low-resistance circuit at a rate higher than that usually achieved on maximum exercise. A ≥10% reduction in FEV1is a positive response to exercise and EVH and, when sustained, is usually associated with release of inflammatory mediators of broncho constriction. Another surrogate, mannitol dry powder, given by inhalation in progressively increasing doses, is used to mimic the dehydrating stimulus of exercise hyperpnoea. A positive mannitol test is a 15% fall in FEV1at ≤635 mg and reveals potential for EIB. Mannitol has a high specificity for identifying a clinical diagnosis of asthma. Once a diagnosis of EIB is established, the athlete needs to know how to avoid EIB. Being treated daily with an inhaled corticosteroid to reduce airway inflammation, inhaling a β2agonist or a cromone immediately before exercise, or taking a leukotriene antagonist several hours before exercise, all inhibit or prevent EIB. Other strategies include warming up prior to exercise and reducing respiratory water and heat loss by using face masks or nasal breathing.
Airway dysfunction in swimmers: Table 1
Authors: Bougault Valérie , Boulet Louis-Philippe
Published: January 2012

Elite competitive swimmers are particularly affected by airway disorders that are probably related to regular and intense training sessions in a chlorinated environment. Upper and lower airway respiratory symptoms, rhinitis, airway hyper-responsiveness, and exercise-induced bronchoconstriction are highly prevalent in these athletes, but their influence on athletic performance is still unclear. The authors reviewed the main upper and lower respiratory ailments observed in competitive swimmers who train in indoor swimming pools, their pathophysiology, clinical significance and possible effects on performance. Issues regarding the screening of these disorders, their management and preventive measures are addressed.
Pericallosal artery aneurysm treatment using Y-configuration stent-assisted coil embolization: a report of four cases
Authors: Darkhabani Ziad M , Lazzaro Marc A , Zaidat Osama O
Published: January 2012

Background

Pericallosal artery aneurysms at the bifurcation represent a special endovascular technical challenge given their distal location, commonly wide-neck morphology, small parent vessel diameter and potentially high recurrence rate after coiling given the bifurcation location. Y-configuration stent-assisted coil embolization techniques have been reported for the treatment of wide-neck aneurysms located at other vascular bifurcations and only rarely with A2 bifurcation aneurysms.

Methods

A neurointerventional database was reviewed for identification of all cases of A2 bifurcation aneurysms that were treated with Y-stent configuration. The authors report clinical, technical and outcome data on four patients with pericallosal aneurysms who were treated with a Y-configuration stent-assisted coil embolization technique.

Results

A Y-configuration stent placement in the anterior cerebral artery/A2 bifurcation was successfully achieved in all four patients without significant technical difficulties. One patient presented with a previously ruptured and partially treated aneurysm and three patients with incidentally found aneurysms. All four patients had a Y-configuration stent placement in one setting. The Y-configuration allowed for complete occlusion of all four aneurysms with no recurrence or arterial occlusion on mean angiographic follow-up of 13.5 months (6–28).

Conclusion

Treating wide-neck pericallosal artery aneurysms at the bifurcation with Y-configuration stent placement is feasible and effective. This technique may be considered as a therapeutic option for wide-neck aneurysms that pose a difficult technical challenge.