bluuebunny/crossref_metadata_2025 huggingface dataset:
The P-element strikes again: the recent invasion of naturalDrosophila simulanspopulations
Authors: Kofler Robert , Hill Tom , Nolte Viola , Betancourt Andrea , Schlötterer Christian
Published: January 2015

The P-element is one of the best understood eukaryotic transposable elements. It invadedDrosophila melanogasterpopulations within a few decades, but was thought to be absent from close relatives, includingD. simulans. Five decades after the spread inD. melanogaster, we provide evidence that the P-element has also invadedD. simulans. P-elements inD. simulansappears to have been acquired recently fromD. melanogasterprobably via a single horizontal transfer event. Expression data indicate that the P-element is processed in the germline ofD. simulans, and genomic data show an enrichment of P-element insertions in putative origins of replication, similar to that seen inD. melanogaster. This ongoing spread of the P-element in natural populations provides an unique opportunity to understand the dynamics of transposable element spreads and the associated piRNA defense mechanisms.
Strong spurious transcription likely a cause of DNA insert bias in typical metagenomic clone libraries
Authors: Lam Kathy N. , Charles Trevor C.
Published: January 2015

Background

Clone libraries provide researchers with a powerful resource with which to study nucleic acid from diverse sources. Metagenomic clone libraries in particular have aided in studies of microbial biodiversity and function, as well as allowed the mining of novel enzymes for specific functions of interest. These libraries are often constructed by cloning large-inserts (∼30 kb) into a cosmid or fosmid vector. Recently, there have been reports of GC bias in fosmid metagenomic clone libraries, and it was speculated that the bias may be a result of fragmentation and loss of AT-rich sequences during the cloning process. However, evidence in the literature suggests that transcriptional activity or gene product toxicity may play a role in library bias.

Results

To explore the possible mechanisms responsible for sequence bias in clone libraries, and in particular whether fragmentation is involved, we constructed a cosmid clone library from a human microbiome sample, and sequenced DNA from three different steps of the library construction process: crude extract DNA, size-selected DNA, and cosmid library DNA. We confirmed a GC bias in the final constructed cosmid library, and we provide strong evidence that the sequence bias is not due to fragmentation and loss of AT-rich sequences but is likely occurring after the DNA is introduced intoE. coli. To investigate the influence of strong constitutive transcription, we searched the sequence data for consensus promoters and found thatrpoD/σ70promoter sequences were underrepresented in the cosmid library. Furthermore, when we examined the reference genomes of taxa that were differentially abundant in the cosmid library relative to the original sample, we found that the bias appears to be more closely correlated with the number ofrpoD/σ70consensus sequences in the genome than with simple GC content.

Conclusions

The GC bias of metagenomic clone libraries does not appear to be due to DNA fragmentation. Rather, analysis of promoter consensus sequences provides support for the hypothesis that strong constitutive transcription from sequences recognized asrpoD/σ70consensus-like inE. colimay lead to plasmid instability or loss of insert DNA. Our results suggest that despite widespread use ofE. colito propagate foreign DNA, the effects ofin vivotranscriptional activity may be under-appreciated. Further work is required to tease apart the effects of transcription from those of gene product toxicity.
ControllingE. coligene expression noise
Authors: Kim Kyung Hyuk , Choi Kiri , Bartley Bryan , Sauro Herbert M.
Published: January 2015

Intracellular protein copy numbers show significant cell-to-cell variability within an isogenic population due to the random nature of biological reactions. Here we show how the variability in copy number can be controlled by perturbing gene expression. Depending on the genetic network and host, different perturbations can be applied to control variability. To understand more fully how noise propagates and behaves in biochemical networks we developed stochastic control analysis (SCA) which is a sensitivity-based analysis framework for the study of noise control. Here we apply SCA to synthetic gene expression systems encoded on plasmids that are transformed intoEscherichia coli. We show that (1) dual control of transcription and translation efficiencies provides the most efficient way of noise-vs.-mean control. (2) The expressed proteins follow the gamma distribution function as found in chromosomal proteins. (3) One of the major sources of noise, leading to the cell-to-cell variability in protein copy numbers, is related to bursty translation. (4) By taking into account stochastic fluctuations in autofluorescence, the correct scaling relationship between the noise and mean levels of the protein copy numbers was recovered for the case of weak fluorescence signals.
SW#db: GPU-accelerated exact sequence similarity database search
Authors: Korpar Matija , Šošić Martin , Blažeka Dino , Šikić Mile
Published: January 2015

The deluge of next-generation sequencing (NGS) data and expanding database poses higher requirements for protein similarity search. State-of-the-art tools such as BLAST are not fast enough to cope with these requirements. Because of that it is necessary to create new algorithms that will be faster while keeping similar sensitivity levels. The majority of protein similarity search methods are based on a seed-and-extend approach which uses standard dynamic programming algorithms in the extend phase. In this paper we present a SW#db tool and library for exact similarity search. Although its running times, as standalone tool, are comparable to running times of BLAST it is primarily designed for the extend phase where there are reduced number of candidates in the database. It uses both GPU and CPU parallelization and when we measured multiple queries on Swiss-prot and Uniref90 databases SW#db was 4 time faster than SSEARCH, 6-10 times faster than CUDASW++ and more than 20 times faster than SSW.
Non-cyanobacterial diazotrophs mediate dinitrogen fixation in biological soil crusts during early crust formation
Authors: Pepe-Ranney Charles , Koechli Chantal , Potrafka Ruth , Andam Cheryl , Eggleston Erin , Garcia-Pichel Ferran , Buckley Daniel H
Published: January 2015

1

Biological soil crusts (BSC) are key components of ecosystem productivity in arid lands and they cover a substantial fraction of the terrestrial surface. In particular, BSC N2-fixation contributes significantly to the nitrogen (N) budget of arid land ecosystems. In mature crusts, N2-fixation is largely attributed to heterocystous cyanobacteria, however, early successional crusts possess few N2-fixing cyanobacteria and this suggests that microorganisms other than cyanobacteria mediate N2-fixation during the critical early stages of BSC development. DNA stable isotope probing (DNA-SIP) with15N2revealed thatClostridiaceaeandProteobacteriaare the most common microorganisms that assimilate15N2in early successional crusts. TheClostridiaceaeidentified are divergent from previously characterized isolates, though N2fixation has previously been observed in this family. The Proteobacteria identified share >98.5 %SSU rRNA gene sequence identity with isolates from genera known to possess diazotrophs (e.g.Pseudomonas,Klebsiella,Shigella, andIdeonella). The low abundance of these heterotrophic diazotrophs in BSC may explain why they have not been characterized previously. Diazotrophs play a critical role in BSC formation and characterization of these organisms represents a crucial step towards understanding how anthropogenic change will affect the formation and ecological function of BSC in arid ecosystems.
The LUX Score: A Metric for Lipidome Homology
Authors: Marella Chakravarthy , Torda Andrew , Schwudke Dominik
Published: January 2015

Motivation: We propose a method for estimating lipidome homologies analogous to the ones used in sequence analysis and phylogenetics. Results: Algorithms were developed to quantify the structural similarity between lipids and to compute chemical space models of sets of lipid structures and lipidomes. When all lipid molecules of the LIPIDMAPS structure database were mapped in such a chemical space, they automatically formed clusters corresponding to conventional chemical families. Homologies between the lipidomes of four yeast strains based on our LUX score reflected the genetic relationship, although the score is based solely on lipid structures. Source code availability: www.lux.fz-borstel.de
Model based normalization improves differential expression calling in low-depth RNA-seq
Authors: Zakharov Pavel N. , Sergushichev Alexey A. , Predeus Alexander V. , Artyomov Maxim N.
Published: January 2015

RNA-seq is a powerful tool for gene expression profiling and differential expression analysis. Its power depends on sequencing depth which limits its high-throughput potential, with 10-15 million reads considered as optimal balance between quality of differential expression calling and cost per sample. We observed, however, that some statistical features of the data, e.g. gene count distribution, are preserved well below 10-15M reads, and found that they improve differential expression analysis at low sequencing depths when distribution statistics is estimated by pooling individual samples to a combined higher-depth library. Using a novel gene-by-gene scaling technique, based on the fact that gene counts obey Pareto-like distribution1, we re-normalize samples towards bigger sequencing depth and show that this leads to significant improvement in differential expression calling, with only a marginal increase in false positive calls. This makes differential expression calling from 3-4M reads comparable to 10-15M reads, improving high-throughput of RNA-sequencing 3-4 fold.
Genome-wide chromatin footprinting reveals changes in replication origin architecture induced by pre-RC assembly
Authors: Belsky Jason A. , MacAlpine Heather K. , Lubelsky Yoav , Hartemink Alexander J. , MacAlpine David M.
Published: January 2015

Start sites of DNA replication are marked by the origin recognition complex (ORC), which coordinates Mcm2–7 helicase loading to form the prereplicative complex (pre-RC). Although pre-RC assembly is well characterized in vitro, the process is poorly understood within the local chromatin environment surrounding replication origins. To reveal how the chromatin architecture modulates origin selection and activation, we “footprinted” nucleosomes, transcription factors, and replication proteins at multiple points during the Saccharomyces cerevisiae cell cycle. Our nucleotide-resolution protein occupancy profiles resolved a precise ORC-dependent footprint at 269 origins in G2. A separate class of inefficient origins exhibited protein occupancy only in G1, suggesting that stable ORC chromatin association in G2 is a determinant of origin efficiency. G1 nucleosome remodeling concomitant with pre-RC assembly expanded the origin nucleosome-free region and enhanced activation efficiency. Finally, the local chromatin environment restricts the loading of the Mcm2–7 double hexamer either upstream of or downstream from the ARS consensus sequence (ACS).
The transcription factor Nerfin-1 prevents reversion of neurons into neural stem cells
Authors: Froldi Francesca , Szuperak Milan , Weng Chen-Fang , Shi Wei , Papenfuss Anthony T. , Cheng Louise Y.
Published: January 2015

Cellular dedifferentiation is the regression of a cell from a specialized state to a more multipotent state and is implicated in cancer. However, the transcriptional network that prevents differentiated cells from reacquiring stem cell fate is so far unclear. Neuroblasts (NBs), the Drosophila neural stem cells, are a model for the regulation of stem cell self-renewal and differentiation. Here we show that the Drosophila zinc finger transcription factor Nervous fingers 1 (Nerfin-1) locks neurons into differentiation, preventing their reversion into NBs. Following Prospero-dependent neuronal specification in the ganglion mother cell (GMC), a Nerfin-1-specific transcriptional program maintains differentiation in the post-mitotic neurons. The loss of Nerfin-1 causes reversion to multipotency and results in tumors in several neural lineages. Both the onset and rate of neuronal dedifferentiation in nerfin-1 mutant lineages are dependent on Myc- and target of rapamycin (Tor)-mediated cellular growth. In addition, Nerfin-1 is required for NB differentiation at the end of neurogenesis. RNA sequencing (RNA-seq) and chromatin immunoprecipitation (ChIP) analysis show that Nerfin-1 administers its function by repression of self-renewing-specific and activation of differentiation-specific genes. Our findings support the model of bidirectional interconvertibility between neural stem cells and their post-mitotic progeny and highlight the importance of the Nerfin-1-regulated transcriptional program in neuronal maintenance.
FBXL20-mediated Vps34 ubiquitination as a p53 controlled checkpoint in regulating autophagy and receptor degradation
Authors: Xiao Juan , Zhang Tao , Xu Daichao , Wang Huibing , Cai Yu , Jin Taijie , Liu Min , Jin Mingzhi , Wu Kejia , Yuan Junying
Published: January 2015

Vacuolar protein-sorting 34 (Vps34), the catalytic subunit in the class III PtdIns3 (phosphatidylinositol 3) kinase complexes, mediates the production of PtdIns3P, a key intracellular lipid involved in regulating autophagy and receptor degradation. However, the signal transduction pathways by which extracellular signals regulate Vps34 complexes and the downstream cellular mechanisms are not well understood. Here we show that DNA damage-activated mitotic arrest and CDK activation lead to the phosphorylation of Vps34, which provides a signal to promote its ubiquitination and proteasomal degradation mediated by FBXL20 (an F-box protein) and the associated Skp1 (S-phase kinase-associated protein-1)–Cullin1 complex, leading to inhibition of autophagy and receptor endocytosis. Furthermore, we show that the expression of FBXL20 is regulated by p53-dependent transcription. Our study provides a molecular pathway by which DNA damage regulates Vps34 complexes and its downstream mechanisms, including autophagy and receptor endocytosis, through SCF (Skp1–Cul1–F-box)-mediated ubiquitination and degradation. Since the expression of FBXL20 is regulated by p53-dependent transcription, the control of Vps34 ubiquitination and proteasomal degradation by FBXL20 and the associated SCF complex expression provides a novel checkpoint for p53 to regulate autophagy and receptor degradation in DNA damage response.
Characterization of Chloroplast Protein Import without Tic56, a Component of the 1-Megadalton Translocon at the Inner Envelope Membrane of Chloroplasts
Authors: Köhler Daniel , Montandon Cyril , Hause Gerd , Majovsky Petra , Kessler Felix , Baginsky Sacha , Agne Birgit
Published: January 2015

We report on the characterization of Tic56, a unique component of the recently identified 1-MD translocon at the inner envelope membrane of chloroplasts (TIC) in Arabidopsis (Arabidopsis thaliana) comprising Tic20, Tic100, and Tic214. We isolated Tic56 by copurification with Tandem Affinity Purification-tagged Toc159 in the absence of precursor protein, indicating spontaneous and translocation-independent formation of the translocon at the outer envelope membrane of chloroplasts (TOC) and TIC supercomplexes. Tic56 mutant plants have an albino phenotype and are unable to grow without an external carbon source. Using specific enrichment of protein amino termini, we analyzed the tic56-1 and plastid protein import2 (toc159) mutants to assess the in vivo import capacity of plastids in mutants of an outer and inner envelope component of the anticipated TOC-TIC supercomplex. In both mutants, we observed processing of several import substrates belonging to various pathways. Our results suggest that despite the severe developmental defects, protein import into Tic56-deficient plastids is functional to a considerable degree, indicating the existence of alternative translocases at the inner envelope membrane.
From community to public ownership: a tale of changing accountabilities
Authors: Fowler Carolyn J. , Cordery Carolyn J.
Published: January 2015

Purpose

– The purpose of this paper is to examine changes in accountability as the provision and control of education moved from private nonprofit organisations to a public sector provider.

Design/methodology/approach

– Analysis of nineteenth century archival documents from significant primary educational providers in a major early New Zealand settlement.

Findings

– The nonprofit education provider utilised public meetings including public examinations, whose effect was to develop trust based on the education values it shared with its community of stakeholders. It also published financial reports which, along with inspections and statistical returns, were preferred once the government became the education provider. Such publications and inspections indicated bureaucracy and control. Nevertheless, government funding, rather than the nonprofit organisation’s dependence on its community, made education provision sustainable.

Research limitations/implications

– It has been suggested that the differences between public sector and private sector accounting and accountability are not always sharply defined (Carnegie and Napier, 2012). However, this case study shows that a change of education provider did lead to a marked difference in accountability. While theory suggests that public sector accountability should enhance democracy, the party best meeting this brief was the nonprofit provider, with the public sector provider preferring hierarchical accountability. It could be argued that funding dependence drove these different approaches as community accountability was traded for financial security.

Originality/value

– Distinctive study of accountability practices to external stakeholders, in a mid-nineteenth century education context.
(Dis)engaging with sustainability: evidence from an Australian business faculty
Authors: Dyball Maria Cadiz , Wang Andy F. , Wright Sue
Published: January 2015

Purpose

– The purpose of this paper is to explore how the lack of staff engagement with a university’s strategy on sustainability could be an enabling lever for organisational change. It examines the attitudes and views of employees of a business faculty at an Australian metropolitan university as it attempts to adopt a holistic approach to sustainability.

Design/methodology/approach

– The paper opted for a case study using data from an on-line survey, semi-directed interviews with key management personnel and archival material. Responses were analysed using Piderit’s (2000) notion of ambivalence.

Findings

– The paper provides empirical insights into why staff lacked engagement with the university’s strategy on sustainability. It suggests that staff were ambivalent, displaying dissonance in their personal beliefs on sustainability, the university’s strategy and the extent of their intentions to support the university. Staff were willing to offer ideas on how the university could, in the future, change towards sustainability. These ideas allow the possibility for the university to learn to adjust the scope of the implementation of its sustainability strategy.

Research limitations/implications

– The research results may lack generalisability. Therefore, researchers are encouraged to further examine staff attitudes on sustainability in higher education using Piderit’s notion of ambivalence. In-depth interviews and focus group discussions could allow a better understanding of harmony and dissonance in cognition of and intention for university sustainability strategies and initiatives by academic, professional and sessional staff.

Practical implications

– The paper includes implications for staff engagement with sustainability in higher education.

Originality/value

– This paper fulfils an identified need to study how staff engagement with sustainability in higher education can be enabled for organisational learning.
Institutional contradictions at and around the annual general meeting
Authors: Johed Gustav , Catasús Bino
Published: January 2015

Purpose

– The purpose of this paper is to examine how a shareholder association prepares for and later act at the annual general meeting. It focusses on how the association evaluates corporate proposals to pay dividends and how they vote on equity distributions at the annual general meeting.

Design/methodology/approach

– This paper relies on observation of the shareholder association before the annual general meeting as well as at the meeting. The analysis is informed by institutional analysis as a way to make sense of how the association experience tension in the setting of the stock market and how it activates responses to these tensions.

Findings

– The shareholder association failed to target companies that comply with an institutionalized view of good ownership despite those companies distributing more equity than the association deems to be in line with sound governance. This the authors understand to result from institutional tensions between a traditional stewardship model of governance and the more recent financial investor logic that emphasizes equity distributions as mean to create shareholder wealth. As good ownership is often equated with long-term committed owners, which makes the association fail to target non-traditional companies that are similar to companies with traditional ownership in terms of dividend ratios.

Research limitations/implications

– The paper demonstrates how institutional logics influence micro-level action in offering guidance to individual members. There are two relevant aspects to this. First, it offers guidance in terms of how to identify whether a corporate proposal is in line with the associations’ policy. Second, institutional logics influence micro-level action because deviations from it require explanations.

Originality/value

– There are so far little qualitative research on how participants in governance mechanism use accounting to take decisions. In this way, the paper adds insight to both investor communities as well as behind the doors of the AGM.
The co-construction of NGO accountability
Authors: O'Dwyer Brendan , Boomsma Roel
Published: January 2015

Purpose

– The purpose of this paper is to deepen and advance the understanding of the construction of accountability within the relationship between government funders and development non-governmental organisations (NGOs).

Design/methodology/approach

– The paper presents a case study examining the process through which an influential Dutch development NGO, Oxfam Novib, constructed its own accountability while simultaneously seeking to influence shifts in government funder accountability requirements. It enrols a combination of comprehensive archival data on the Dutch government’s financing scheme for NGOs from 1965 to 2012 and in-depth interviews with Oxfam Novib managers and Dutch government officials. The co-evolution in accountability within Oxfam Novib and the government funding scheme is conceptualised using the notions of imposed, felt and adaptive accountability

Findings

– The case unveils the dynamics through which accountability within a major government funding scheme for NGOs was co-constructed by Oxfam Novib and the Dutch government’s development aid department. In particular, it reveals how this process was influenced by an internal evolution in Oxfam Novib’s organisational approach to accountability and an institutional context characterised by consensus-based economic and social policy making. The case also unveils the process through which Oxfam Novib’s influence declined as more demanding, narrowly focused government accountability requirements emerged in a setting that was increasingly critical of NGOs.

Originality/value

– The paper presents a rare example of a context where development NGOs have proactively sought and secured influence over the accountability demands of a key donor. It is unique in combining consideration of the internal evolution of accountability within an individual NGO (conceptualised as an evolution from felt to adaptive accountability) with a progression in the form of accountability required by governmental funders. The paper unveils the conditions under which NGO-preferred conceptions of accountability may gain (and lose) influence among key funders.
Electrical studies on biopolyurethane from cashew nut husk tannin
Authors: Sunija A.J. , Siva Ilango S. , Vinod Kumar K.P
Published: January 2015

Purpose

– This paper aims to focus on the evaluation of the electrical properties of bio-based polyurethane material derived from cashew nut husk tannin and also the effect of temperature and frequency on the dielectric values and alternate current (AC) conductivity.

Design/methodology/approach

– Bio-based polyurethane is prepared from cashew nut husk tannin as polyol, their dielectric constant and dielectric loss factor are measured using an inductance capacitance resistance (LCR) metre, and the AC conductivity is determined using dielectric constant and loss values.

Findings

– The dielectric constant values are high, and the values decrease with an increase in frequency but increase with an increase in temperature. The AC conductivity values are low; hence, the material can be categorized as insulators or semi-conductors. Because the polyurethanes have a good dielectric value and are cost-effective, as they are derived from renewable biomaterial waste, they have promising applications for the future.

Research limitations/implications

– The experiment is carried out up to the frequency of 200 KHz because of the limitation in the instrument. But for the institute of printed circuits (IPC) and other specifications, the values of dielectric loss and dielectric constant will be generally coated for 1 MHz.

Practical implications

– The high dielectric constant and loss values show that the polyurethane can be opted for use as capacitors in electronic devices, and the values are comparable to the requirements of IPC4101A/24IPC; hence, they are suitable for the application as printed circuit board (PCB) laminate.

Social implications

– The use of biomaterial waste in the production of polyurethane will bring down the dependence of polyurethane industry on fossil fuel reserve, reduce carbon dioxide foot print and reduce the cost of production.

Originality/value

– The motivation of the work was its ecological aspect and also aims on the use of an alternative bio-based material in the PCB industry.
Multiphysics coupling simulation of RDE for PCB manufacturing
Authors: Ji Linxian , Wang Chong , Wang Shouxu , He Wei , Xiao Dingjun , Tan Ze
Published: January 2015

Purpose

– The purpose of this paper is to optimize experimental parameters and gain further insights into the plating process in the fabrication of high-density interconnections of printed circuit boards (PCBs) by the rotating disc electrode (RDE) model. Via metallization by copper electrodeposition for interconnection of PCBs has become increasingly important. In this metallization technique, copper is directly filled into the vias using special additives. To investigate electrochemical reaction mechanisms of electrodeposition in aqueous solutions, using experiments on an RDE is common practice.

Design/methodology/approach

– An electrochemical model is presented to describe the kinetics of copper electrodeposition on an RDE, which builds a bridge between the theoretical and experimental study for non-uniform copper electrodeposition in PCB manufacturing. Comsol Multiphysics, a multiphysics simulation platform, is invited to modeling flow field and potential distribution based on a two-dimensional (2D) axisymmetric physical modeling. The flow pattern in the electrolyte is determined by the 2D Navier–Stokes equations. Primary, secondary and tertiary current distributions are performed by the finite element method of multiphysics coupling.

Findings

– The ion concentration gradient near the cathode and the thickness of the diffusion layer under different rotating velocities are achieved by the finite element method of multiphysics coupling. The calculated concentration and boundary layer thicknesses agree well with those from the theoretical Levich equation. The effect of fluid flow on the current distribution over the electrode surface is also investigated in this model. The results reveal the impact of flow parameters on the current density distribution and thickness of plating layer, which are most concerned in the production of PCBs.

Originality/value

– By RDE electrochemical model, we build a bridge between the theoretical and experimental study for control of uniformity of plating layer by concentration boundary layer in PCB manufacturing. By means of a multiphysics coupling platform, we can accurately analyze and forecast the characteristic of the entire electrochemical system. These results reveal theoretical connections of current density distribution and plating thickness, with controlled parameters in the plating process to further help us comprehensively understand the mechanism of copper electrodeposition.
Computing method of thermal conductivity of heat dissipation vias in printed circuit board and its optimization
Authors: Xiao Shuo , Zhao Yang , Cao Yuan , Jiang Haifeng , Zhu Wenliang
Published: January 2015

Purpose

– This paper aims to deduce a set of theory computational formula, and optimize and improve the heat conductivity of vias in printed circuit boards of electrical power apparatus.

Design/methodology/approach

– The authors adopted numerical simulation and experimental measurement to verify the reliability of this formula.

Findings

– Research result showed that 0.45 mm was the optimal bore diameter of vias; the conductivity had no obvious improvement when filling material was FR4 or Rogers, but if it was filled with texture of high thermal conductivity like soldering tine, the conductivity would improve a lot; the plating thickness of vias had a greater influence on thermal conductivity.

Originality/value

– Through the theory computational formula, this paper studied the influence of aperture of vias, filled materials and thickness of copper plated on vias on thermal conductivity.
Temperature simulation and its application in on-line temperature measurement of a micro drill bit
Authors: Shi Hongyan , Li Hui , Chen Shengzhi
Published: January 2015

Purpose

– The purpose of this paper is to obtain the micro drill bit temperature field distribution in micro-drilling process and the temperature drop in retracting process with simulation software. Meanwhile, the key factors that affect the micro drill bit temperature will be obtained as well. The results can also be used to improve the accuracy in on-line drilling temperature measurement.

Design/methodology/approach

– The purpose of this paper is to obtain the micro drill bit temperature field distribution in micro-drilling process and the temperature drop in retracting process with simulation software. Meanwhile, the key factors that affect the micro drill bit temperature will be obtained as well. The results can also be used to improve the accuracy in on-line drilling temperature measurement.

Findings

– Micro drill bit high-temperature area mainly concentrates in the cutting edge and chisel edge. With the increase of spindle speed and feed speed, the micro drill bit highest temperature increased. The micro drill bit temperature drop rate reaches 20° in the micro-drilling retraction process with certain parameters. The micro drill bit highest temperature detected by an infrared camera is lower by 22° than that in real drilling. The simulation results can be used to guide the actual industrial production.

Originality/value

– The simulation results can be applied to revise the temperature measurement by an infrared camera in the drilling process. Drilling experiments show that the simulation method is correct and has certain practical significance. The current temperature measurement method can satisfy most of the requirements of temperature measurements.
Trust in school: a pathway to inhibit teacher burnout?
Authors: Van Maele Dimitri , Van Houtte Mieke
Published: January 2015

Purpose

– The purpose of this paper is to consider trust as an important relational source in schools by exploring whether trust lowers teacher burnout. The authors examine how trust relationships with different school parties such as the principal relate to distinct dimensions of teacher burnout. The authors further analyze whether school-level trust additionally influences burnout. In doing this, the authors account for other teacher and school characteristics.

Design/methodology/approach

– The authors use quantitative data gathered during the 2008-2009 school year from 673 teachers across 58 elementary schools in Flanders (i.e. the northern Dutch-speaking region of Belgium). Because teacher and school characteristics are simultaneously related to burnout, multilevel modeling is applied.

Findings

– Trust can act as a buffer against teacher burnout. Teachers’ trust in students demonstrates the strongest association with burnout compared to trust in principals or colleagues. Exploring relationships of trust in distinct school parties with different burnout dimensions yield interesting additional insights such as the specific importance of teacher-principal trust for teachers’ emotional exhaustion. Burnout is further an individual teacher matter to which school-level factors are mainly unrelated.

Research limitations/implications

– Principals fulfill an important role in inhibiting emotional exhaustion among teachers. They are advised to create a school atmosphere that is conducive for different kinds of trust relationships to develop. Actions to strengthen trust and inhibit teacher burnout are necessary, although further qualitative and longitudinal research is desirable.

Originality/value

– This paper offers a unique contribution by examining trust in different school parties as a relational buffer against teacher burnout. It indicates that principals can affect teacher burnout and prevent emotional exhaustion by nurturing trusting relationships in school.
Principals’ social interactions with teachers
Authors: Price Heather E.
Published: January 2015

Purpose

– The purpose of this paper is to link the social interactions between principals and their teachers to teachers’ perceptions of their students’ engagement with school, empirically testing the theoretical proposition that principals influence students through their teachers in the US charter school environment. The mediating influence of latent beliefs of trust and support are tested in this process.

Design/methodology/approach

– By analyzing pooled network and survey data collected in 15 Indianapolis charter schools using stepwise, fixed-effects regression techniques, this study tests the association between interactions of principals and teachers, on the one hand, and teachers’ perceptions of student engagement, on the other. The extent to which latent beliefs about teachers – in particular, trust in teachers and support of teachers by the administrators – mediate this relationship is also tested.

Findings

– Direct relationships between principal-teacher interactions and latent beliefs of trust and support are confirmed. Direct relationships between latent beliefs and perceptions of academic and school engagement are also confirmed. There is a relationship between principal-teacher interactions and teacher perceptions of student engagement, but the mediating effect of latent beliefs of trust and support accounts for much of the direct association. The reachability of the principal remains a significant and direct influence on teachers’ perceptions of academic engagement after accounting for trust and support.

Research limitations/implications

– Moving beyond principals’ personality dispositions in management and turning to the social relationships that they form with teachers adds to the understanding of how principal leadership affects student learning. Empirically distinguishing between the actual interactions and social dispositions of principals helps inform practical implications. Focussing on how principals’ social interactions with teachers influence teachers’ perceptions of students’ engagement provides a theoretical link as to how principals indirectly influence student achievement.

Practical implications

– The relationships that principals build with teachers have real implications on the beliefs of trust and support among teachers in a school and have a ripple effect on teachers’ perceptions of student engagement. These findings therefore suggest that frequently moving principals among schools is not an ideal policy.

Originality/value

– This study tests the theoretical boundaries of school organization research by using a within-schools design with charter schools. It also links leadership research to outcomes typically restricted to research on school culture and climate.
Faculty trust in the principal: an essential ingredient in high-performing schools
Authors: Tschannen-Moran Megan , Gareis Christopher R.
Published: January 2015

Purpose

– The purpose of this paper is to explore the relationships among faculty trust in the principal, principal leadership behaviors, school climate, and student achievement.

Design/methodology/approach

– Data from 64 elementary, middle, and high schools in two school districts formed the basis of the study (n=3,215 teachers), allowing for correlational and regression analyses of the variables.

Findings

– The authors found that faculty trust in the principal was related to perceptions of both collegial and instructional leadership, as well as to factors of school climate such as teacher professionalism, academic press, and community engagement. Student achievement was also correlated with trust, principal leadership behaviors, and school climate. The authors found that both of the composite variables, principal behaviors and school climate, made significant independent contributions to explaining variance in student achievement and that together they explained 75 percent of the variance in achievement.

Research limitations/implications

– Limitations of the study include the use of a single form to collect participants’ responses that may have elevated the degree of correlations, as well as the exclusion of rural schools from the sample.

Practical implications

– The findings of this study suggest that principals must foster and maintain trust in order to lead schools effectively. Importantly, trust has both interpersonal and task-oriented dimensions. Thus, principals must be prepared to engage collegially with teachers in ways that are consistently honest, open, and benevolent, while also dependably demonstrating sound knowledge and competent decision making associated with administering academic programs.

Originality/value

– Situated in a conceptual framework of systems theory, this study explored the interplay of faculty trust in the principal, principal behavior, school climate, and student achievement. The findings suggest that it is necessary for principals to evidence both interpersonal and task-oriented behaviors in order to be trusted by teachers. Furthermore, the strength of the relationships suggests that schools will not be successful in fostering student learning without trustworthy school leaders who are skillful in cultivating academic press, teacher professionalism, and community engagement in their schools.
The networked principal
Authors: Moolenaar Nienke M. , Sleegers Peter J. C.
Published: January 2015

Purpose

– While in everyday practice, school leaders are often involved in social relationships with a variety of stakeholders both within and outside their own schools, studies on school leaders’ networks often focus either on networks within or outside schools. The purpose of this paper is to investigate the extent to which principals occupy similar positions in their school’s network and the larger district network. In addition, the authors examined whether principals’ centrality in both networks can be attributed to demographic characteristics and transformational leadership (TL).

Design/methodology/approach

– Using social network analysis, correlational and regression analysis, and an advanced social network technique, namely p2 modeling, the authors analyzed data collected among 708 educators in 46 Dutch elementary schools. The authors also offer a visualization of the district social network to explore principals’ relationships with other principals in the district.

Findings

– Results suggest that principals who occupy a central position in their school’s advice network are also more likely to occupy a central position in their district’s collaborative leadership network. Moreover, TL was found to affect the extent to which principals are central in both networks.

Originality/value

– The study is unique as it simultaneously explores principals’ social relationships in schools and the larger district. Moreover, the authors advance the knowledge of TL as a possible mechanism that may shape the pattern of these relationships, thereby connecting two streams of literature that were until now largely disconnected. Limitations to the study warrant further qualitative and longitudinal research on principals’ social relationships in schools, districts, and the larger community.
Administrative context and novice teacher-mentor interactions
Authors: Pogodzinski Ben
Published: January 2015

Purpose

– Mentoring can improve novice teacher effectiveness and reduce teacher attrition, yet the depth and breadth of mentoring can vary greatly within and between schools. The purpose of this paper is to identify the extent to which a school’s administrative context is associated with the focus and frequency of novice teacher-mentor interactions.

Design/methodology/approach

– By estimating logistic regression models, the author identified the association between novices’ perceptions of their working conditions and the content and frequency of interactions with their formally assigned mentors.

Findings

– When novice teachers perceived positive administrator-teacher relations in their schools and reported that administrative duties did not interfere with their core work as teachers, they were more likely to frequently interact with their mentors around issues of curriculum.

Research limitations/implications

– Studies of new teacher induction need to more fully account for elements of school-level organizational context which influence novice teacher-mentor interactions, specifically related to administrative decision making and climate. Future research should seek to identify the extent to which formal policy related to new teacher induction is supported by broader elements of the organizational context.

Practical implications

– In addition to implementing sound formal policies related to teacher mentoring, school administrators should seek to foster a school climate that promotes administrator-teacher and teacher-teacher collaboration to promote improved teacher mentoring.

Originality/value

– This study builds upon previous research by drawing attention to the association between broad measures of school-level administrative context related to the quality of working conditions and teacher mentoring.
The dilemma of internal audit function adaptation
Authors: Elbardan Hany , Ali Maged , Ghoneim Ahmad
Published: January 2015

Purpose

– The purpose of this paper is to provide a conceptual framework that helps to investigate how the internal audit function (IAF) responds to both the introduction of the control logic of Enterprise Resource Planning (ERP) systems, and corporate governance’s (CG) institutional pressures. Furthermore, the paper aims to articulate the concurrence between the external pressures of CG and internal control logic of ERP systems.

Design/methodology/approach

– The paper presents a review of the normative literature pertaining to the increase in significance of CG in the light of the worldwide economic crisis. The paper highlights a literature gap related to the lack of studies focusing on the impact of ERP systems implementation on the IAF practices.

Findings

– The authors articulate institutional theory to formulate a conceptual framework that explains the reciprocal interplay between the macro external governance pressures, micro internal institutional logics inscribed in the ERP systems and their effect on IAF practices and structure within organisations.

Research limitations/implications

– The paper is conceptual in nature and therefore the proposed framework will be subsequently validated using a qualitative research approach in future research.

Practical implications

– The conceptual framework would offer the internal auditors some strategies for enabling adaptation to the different internal and external pressures. Also the paper provides a platform for research community to investigate the influence of CG and ERP systems implementation on IAF adaptation.

Originality/value

– The paper provides a clearer articulation of the various constructs that affect the IAF, which has gained great attention for assuring good CG.
The critical success factors (CSFs) for Enterprise Software contract negotiations
Authors: Palanisamy Ramaraj , Verville Jacques , Taskin Nazim
Published: January 2015

Purpose

– As the wrong Enterprise Software (ES) acquisition can lead an organization with chronically exceeded budgets and settling for minimum returns, so can an unfavorable contractual agreement. Often the acquiring organizations become vulnerable to risks and mistakes as the software contracts are habitually written using legal terminologies and mainly to the advantage of the vendor. To avoid costly ES contracting mistakes, the purpose of this paper is to empirically identify the critical success factors (CSFs) of contracting in the context of ES acquisition.

Design/methodology/approach

– A questionnaire survey was conducted to gather the data for this study. Statistical analysis conducted for this study include descriptive statistics, factor analysis with reliability and validity tests and nonparametric test.

Findings

– The five key factors are: contractual assurance, forward compatibility and licensing; right to use, own and use of own, confidentiality and payment; software acceptance; license assignment; and vendor obligation for intellectual property. The research and managerial implications of these factors are given in discussion.

Research limitations/implications

– As with most empirical studies, the subjectivity of the opinion of respondents from only two industries presents some limitations to generalization. Another limitation is the respondent has been asked for the degree of criticality for each of the contracting issue given in the questionnaire. There could be critical issues other than the listed ones which are more specific to the organization.

Practical implications

– The results can be used by managers to improve their understanding on the critical contractual issues in ES acquisition negotiations.

Originality/value

– The significant value of this study identifies the CSFs for ES contract negotiations while acquiring the software.