bluuebunny/crossref_metadata_2025 huggingface dataset:
Metal complexation by organic ligands (L) in near-pristine estuarine waters: evidence for the identity of L
Authors: Murray Hollydawn , Meunier Guillaume , Stengel Dagmar B. , Cave Rachel
Published: April 2014

Environmental context Metal toxicity to marirne organisms is largely controlled by organic ligands (L) although the source, structure and stimuli of most ligands remain unknown. We studied trends in Cd and Zn complexing ligands in a near-pristine Irish estuary to gain clues on the identity of L in natural waters. The evidence suggests the naturally occurring Cd ligands include fulvic acids whereas the Zn ligands are likely to be exuded from seaweeds. Further research is required to determine their exact identity. Abstract Trace metal interactions with organic ligands largely control metal bioavailability in marine systems, although little is known about the identity of the ligands. To gain insight into the identity of metal complexing ligands (L), surface water and four species of brown seaweed were sampled from four sites in a region of the Lough Furnace Estuary, Ireland with varying salinity. We measured metal (Cd, Cu, Pb, Zn) speciation, complexing ligands, stability constants (log K′), glutathione (GSH), cysteine (Cys) and seaweed metal contents. Although prevalent in seaweed tissue, dissolved Cu and Pb concentrations in water were below the detection limits. Both Cd and Zn occurred in seaweed tissue. In water, both Cd and Zn occurred predominantly complexed to ligands. Levels of complexed Zn increased with decreasing salinity, increasing from 77% at high salinity to 100% at low salinity. Total dissolved Cd showed a mid-salinity decrease in complexation. The concentration of zinc ligands (LZn) ranged from 27.41nM at high salinity to 95.81nM at mid-salinity. Cd ligands (LCd) occurred in the highest concentration, 8.72nM, at mid-salinity. Comparison of the log K′ values with known ligands provided evidence of their identity: similarities were identified for LCd and fulvic acid, and LZn and macroalgal exudates.
Spatially-explicit modelling of grassland classes – an improved method of integrating a climate-based classification model with interpolated climate surfaces
Authors: Liu Xiaoni , Wang Hongxia , Guo Jing , Wei Jingqiong , Ren Zhengchao , Zhang Jinglan , Zhang Degang , Pan Dongrong , Wang Fengping
Published: April 2014

Spatially-explicit modelling of grassland classes is important to site-specific planning for improving grassland and environmental management over large areas. In this study, a climate-based grassland classification model, the Comprehensive and Sequential Classification System (CSCS) was integrated with spatially interpolated climate data to classify grassland in Gansu province, China. The study area is characterised by complex topographic features imposed by plateaus, high mountains, basins and deserts. To improve the quality of the interpolated climate data and the quality of the spatial classification over this complex topography, three linear regression methods, namely an analytic method based on multiple regression and residues (AMMRR), a modification of the AMMRR method through adding the effect of slope and aspect to the interpolation analysis (M-AMMRR) and a method which replaces the inverse distance-weighted approach for residue interpolation in M-AMMRR with an ordinary kriging approach (I-AMMRR), for interpolating climate variables were evaluated. The interpolation outcomes from the best interpolation method were then used in the CSCS model to classify the grassland in the study area. Climate variables interpolated included the annual cumulative temperature and annual total precipitation. The results indicated that the AMMRR and M-AMMRR methods generated acceptable climate surfaces but the best model fit and cross validation result were achieved by the I-AMMRR method. Twenty-six grassland classes were classified for the study area. The four grassland vegetation classes that covered more than half of the total study area were ‘cool temperate-arid temperate zonal semi-desert’, ‘cool temperate-humid forest steppe and deciduous broad-leaved forest’, ‘temperate-extra-arid temperate zonal desert’, and ‘frigid per-humid rain tundra and alpine meadow’. The vegetation classification map generated in this study provides spatial information on the locations and extents of the different grassland classes. This information can be used to facilitate government agencies’ decision-making in land-use planning and environmental management, and for vegetation and biodiversity conservation. The information can also be used to assist land managers in the estimation of safe carrying capacities, which will help to prevent overgrazing and land degradation.
Acoustically trapped colloidal crystals that are reconfigurable in real time
Authors: Caleap Mihai , Drinkwater Bruce W.
Published: April 2014

Significance

We have been working on metamaterials that are reconfigurable in real time with a view to creating genuinely active metamaterials. Such materials will allow researchers to gain unprecedented control over a range of optical and acoustic wave phenomena. To date, although numerous examples of metamaterials exist, none is reconfigurable in three dimensions. We have developed a method for creating three-dimensional colloidal crystals that are reconfigurable in real time. Our method uses acoustic assembly to trap a suspension of microspheres in patterns resembling crystal lattices. We show that it is possible to dynamically alter the geometry of the colloidal crystal and use our metamaterial as an ultrasonic filter that can be tuned in real time.
A review of early life history dynamics of Barents Sea cod (Gadus morhua)
Authors: Ottersen Geir , Bogstad Bjarte , Yaragina Natalia A. , Stige Leif Christian , Vikebø Frode B. , Dalpadado Padmini
Published: April 2014

The Barents Sea stock of Atlantic cod (Gadus morhua) is currently the world's largest cod stock. It is also a stock for which long time-series are available and much research has been carried out. With this review, we wish to present an overview and evaluation of the knowledge on Barents Sea cod early life dynamics. The focus is on the effects of the biotic and abiotic drivers, which jointly determine the strength of a year class. A stage-by-stage approach is employed. We summarize and assess the significance of the different processes described in the literature to be at play during each specific life stage, from spawning stock, through eggs, larvae, and pelagic juvenile, to demersal juvenile and recruitment at age 3. Also Russian work is included, some of which until now has not been available to non-Russian readers. Physical drivers examined include sea temperature, advection and dispersal, wind-induced turbulence, and light. Biotic mechanisms studied range from maternal effects and skipped spawning in the adult stock through egg quantity and quality, to prey availability for the larvae and effects of cannibalism on the juveniles. Finally, we evaluate the main hypotheses put forth by Johan Hjort a hundred years ago in the light of our synthesis of present knowledge. A main conclusion is that it is unlikely that there is any one single life stage during which recruitment with any generality is determined.
Influence of platelet-activating factor, lyso-platelet-activating factor and edelfosine on Langmuir monolayers imitating plasma membranes of cell lines differing in susceptibility to anti-cancer treatment: the effect of plasmalogen level
Authors: Flasiński Michał , Hąc-Wydro Katarzyna , Wydro Paweł , Dynarowicz-Łątka Patrycja
Published: April 2014

Three structurally related but differing in biological activities single-chained ether phospholipids (PAF (platelet-activating factor) and lyso-PAF) and an anti-cancer drug (edelfosine (ED)) were investigated in Langmuir monolayers imitating natural membranes. The aim of the undertaken experiments was to study the influence of these lipids on monolayers mimicking plasma membranes of cell lines differing in susceptibility to the anti-cancer activity of ED, i.e. promyelocytic leukaemia cells (HL-60) and promyeloblastic leukaemia cells (K-562). As these cells differ essentially in the cholesterol/phospholipid ratio and plasmalogen concentration in the membrane, we have carried out systematic investigations in artificial systems of various compositions. The results for model leukaemia cell membrane were compared with data acquired for systems imitating normal leucocytes. Our results show that the level of plasmalogens significantly modulates the influence of the single-chained phospholipids on the investigated systems. The experiments confirmed also that the interactions of ether lipids with a model membrane of HL-60 cells (in biological tests sensitive to ED) have opposite character when compared with K-562, being resistant to ED. Moreover, the values of the parameters characterizing monolayers serving as membrane models (strength of interactions, monolayers fluidity and morphology) proved both sensitivity of these cells to ED and lack of their susceptibility towards PAF. Interestingly, it has been found that lyso-PAF, which is usually described as an inactive precursor of PAF, displays a stronger effect on HL-60 model membranes than ED.
Exact model reduction with delays: closed-form distributions and extensions to fully bi-directional monomolecular reactions
Authors: Leier Andre , Barrio Manuel , Marquez-Lago Tatiana T.
Published: April 2014

In order to systematically understand the qualitative and quantitative behaviour of chemical reaction networks, scientists must derive and analyse associated mathematical models. However, biochemical systems are often very large, with reactions occurring at multiple time scales, as evidenced by signalling pathways and gene expression kinetics. Owing to the associated computational costs, it is then many times impractical, if not impossible, to solve or simulate these systems with an appropriate level of detail. By consequence, there is a growing interest in developing techniques for the simplification or reduction of complex biochemical systems. Here, we extend our recently presented methodology on exact reduction of linear chains of reactions with delay distributions in two ways. First, we report that it is now possible to deal with fully bi-directional monomolecular systems, including degradations, synthesis and generalized bypass reactions. Second, we provide all derivations of associated delays in analytical, closed form. Both advances have a major impact on further reducing computational costs, while still retaining full accuracy. Thus, we expect our new methodology to respond to current simulation needs in pharmaceutical, chemical and biological research.
On nonlinear viscoelastic deformations: a reappraisal of Fung's quasi-linear viscoelastic model
Authors: De Pascalis Riccardo , Abrahams I. David , Parnell William J.
Published: April 2014

This paper offers a reappraisal of Fung's model for quasi-linear viscoelasticity. It is shown that a number of negative features exhibited in other works, commonly attributed to the Fung approach, are merely a consequence of the way it has been applied. The approach outlined herein is shown to yield improved behaviour and offers a straightforward scheme for solving a wide range of models. Results from the new model are contrasted with those in the literature for the case of uniaxial elongation of a bar: for an imposed stretch of an incompressible bar and for an imposed load. In the latter case, a numerical solution to a Volterra integral equation is required to obtain the results. This is achieved by a high-order discretization scheme. Finally, the stretch of a compressible viscoelastic bar is determined for two distinct materials: Horgan–Murphy and Gent.
Randomly selected suppressor mutations in genes for NADH : quinone oxidoreductase-1, which rescue motility of a Salmonella ubiquinone-biosynthesis mutant strain
Authors: Barker Clive S. , Meshcheryakova Irina V. , Sasaki Toshio , Roy Michael C. , Sinha Prem Kumar , Yagi Takao , Samatey Fadel A.
Published: April 2014

The primary mobile electron-carrier in the aerobic respiratory chain ofSalmonellais ubiquinone. Demethylmenaquinone and menaquinone are alternative electron-carriers involved in anaerobic respiration. Ubiquinone biosynthesis was disrupted in strains bearing deletions of theubiAorubiEgenes. In soft tryptone agar both mutant strains swam poorly. However, theubiAdeletion mutant strain produced suppressor mutant strains with somewhat rescued motility and growth. Six independent suppressor mutants were purified and comparative genome sequence analysis revealed that they each bore a single new missense mutation, which localized to genes for subunits of NADH : quinone oxidoreductase-1. Four mutants bore an identicalnuoG(Q297K) mutation, one mutant bore anuoM(A254S) mutation and one mutant bore anuoN(A444E) mutation. The NuoG subunit is part of the hydrophilic domain of NADH : quinone oxidoreductase-1 and the NuoM and NuoN subunits are part of the hydrophobic membrane-embedded domain. Respiration was rescued and the suppressed mutant strains grew better in Luria–Bertani broth medium and could usel-malate as a sole carbon source. The quinone pool of the cytoplasmic membrane was characterized by reversed-phase HPLC. Wild-type cells made ubiquinone and menaquinone. Strains with aubiAdeletion mutation made demethylmenaquinone and menaquinone and theubiEdeletion mutant strain made demethylmenaquinone and 2-octaprenyl-6-methoxy-1,4-benzoquinone; the total quinone pool was reduced. Immunoblotting found increased NADH : quinone oxidoreductase-1 levels for ubiquinone-biosynthesis mutant strains and enzyme assays measured electron transfer from NADH to demethylmenaquinone or menaquinone. Under certain growth conditions the suppressor mutations improved electron flow activity of NADH : quinone oxidoreductase-1 for cells bearing aubiAdeletion mutation.
The Mitochondrial Sulfur Dioxygenase ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 Is Required for Amino Acid Catabolism during Carbohydrate Starvation and Embryo Development in Arabidopsis
Authors: Krüßel Lena , Junemann Johannes , Wirtz Markus , Birke Hannah , Thornton Jeremy D. , Browning Luke W. , Poschet Gernot , Hell Rüdiger , Balk Janneke , Braun Hans-Peter , Hildebrandt Tatjana M.
Published: April 2014

The sulfur dioxygenase ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 (ETHE1) catalyzes the oxidation of persulfides in the mitochondrial matrix and is essential for early embryo development in Arabidopsis (Arabidopsis thaliana). We investigated the biochemical and physiological functions of ETHE1 in plant metabolism using recombinant Arabidopsis ETHE1 and three transfer DNA insertion lines with 50% to 99% decreased sulfur dioxygenase activity. Our results identified a new mitochondrial pathway catalyzing the detoxification of reduced sulfur species derived from cysteine catabolism by oxidation to thiosulfate. Knockdown of the sulfur dioxygenase impaired embryo development and produced phenotypes of starvation-induced chlorosis during short-day growth conditions and extended darkness, indicating that ETHE1 has a key function in situations of high protein turnover, such as seed production and the use of amino acids as alternative respiratory substrates during carbohydrate starvation. The amino acid profile of mutant plants was similar to that caused by defects in the electron-transfer flavoprotein/electron-transfer flavoprotein:ubiquinone oxidoreductase complex and associated dehydrogenases. Thus, in addition to sulfur amino acid catabolism, ETHE1 also affects the oxidation of branched-chain amino acids and lysine.
Benchmarking and validation of aGeant4–SHADOWMonte Carlo simulation for dose calculations in microbeam radiation therapy
Authors: Cornelius Iwan , Guatelli Susanna , Fournier Pauline , Crosbie Jeffrey C. , Sanchez del Rio Manuel , Bräuer-Krisch Elke , Rosenfeld Anatoly , Lerch Michael
Published: April 2014

Microbeam radiation therapy (MRT) is a synchrotron-based radiotherapy modality that uses high-intensity beams of spatially fractionated radiation to treat tumours. The rapid evolution of MRT towards clinical trials demands accurate treatment planning systems (TPS), as well as independent tools for the verification of TPS calculated dose distributions in order to ensure patient safety and treatment efficacy. Monte Carlo computer simulation represents the most accurate method of dose calculation in patient geometries and is best suited for the purpose of TPS verification. A Monte Carlo model of the ID17 biomedical beamline at the European Synchrotron Radiation Facility has been developed, including recent modifications, using theGeant4Monte Carlo toolkit interfaced with theSHADOWX-ray optics and ray-tracing libraries. The code was benchmarked by simulating dose profiles in water-equivalent phantoms subject to irradiation by broad-beam (without spatial fractionation) and microbeam (with spatial fractionation) fields, and comparing against those calculated with a previous model of the beamline developed using thePENELOPEcode. Validation against additional experimental dose profiles in water-equivalent phantoms subject to broad-beam irradiation was also performed. Good agreement between codes was observed, with the exception of out-of-field doses and toward the field edge for larger field sizes. Microbeam results showed good agreement between both codes and experimental results within uncertainties. Results of the experimental validation showed agreement for different beamline configurations. The asymmetry in the out-of-field dose profiles due to polarization effects was also investigated, yielding important information for the treatment planning process in MRT. This work represents an important step in the development of a Monte Carlo-based independent verification tool for treatment planning in MRT.
Polarization control of an X-ray free-electron laser with a diamond phase retarder
Authors: Suzuki Motohiro , Inubushi Yuichi , Yabashi Makina , Ishikawa Tetsuya
Published: April 2014

A diamond phase retarder was applied to control the polarization states of a hard X-ray free-electron laser (XFEL) in the photon energy range 5–20 keV. The horizontal polarization of the XFEL beam generated from the planar undulators of the SPring-8 Angstrom Compact Free-Electron Laser (SACLA) was converted into vertical or circular polarization of either helicity by adjusting the angular offset of the diamond crystal from the exact Bragg condition. Using a 1.5 mm-thick crystal, a high degree of circular polarization, 97%, was obtained for 11.56 keV monochromatic X-rays, whereas the degree of vertical polarization was 67%, both of which agreed with the estimations including the energy bandwidth of the Si 111 beamline monochromator.
Design of Experiments in a higher education setting
Authors: Antony Jiju , Sivanathan Laxman , Gijo E.V.
Published: April 2014

Purpose

– The purpose of this paper is to explore the use of Design of Experiments (DoE) in a higher education setting and to remove the misconception that it is only applied to a manufacturing environment. The authors demonstrate a simple case study here to illustrate its application in a typical non-manufacturing context.

Design/methodology/approach

– The methodology involves the execution of a simple study in the form of an experiment in the Faculty of Engineering, University of Strathclyde. The experiment was performed with the assistance of both undergraduate and postgraduate students in one department in the Faculty of Engineering.

Findings

– It was found from the experiment that postgraduate students prefer a case study approach of teaching with multiple speakers and prefer their classes in the morning. As for undergraduate students, similar results were obtained but would prefer their classes in the afternoon. Moreover further analysis shows that the postgraduate students prefer a 30 minutes introduction to the topic in a one hour lecture. Moreover the students prefer more time to be spent on the exercises and less time on the discussion.

Research limitations/implications

– The sample size of the experiment was considered small in the study although this was a pilot study to investigate the use of DoE in a higher education setting. The authors will continue to collect more data for further validity of results obtained from the pilot study. The authors will also explore the use of different designs as part of the future investigations.

Practical implications

– The outcome of this experiment would help everyone who is involved in teaching to understand the factors and their influences to improve students’ satisfaction scores during the delivery of teaching.

Originality/value

– This paper shows how DoE as a pure manufacturing technique can be extended to a higher education setting. The results of this study were quite an eye opener for the authors in terms of understanding the key factors which influence any process irrespective of the sector.
Heuristic semantic walk for concept chaining in collaborative networks
Authors: Franzoni Valentina , Milani Alfredo
Published: April 2014

Purpose

– In this work, a new general framework is proposed to guide navigation over a collaborative concept network, in order to discover paths between concepts. Finding semantic chains between concepts over a semantic network is an issue of great interest for many applications, such as explanation generation and query expansion. Collaborative concept networks over the web tend to have features such as large dimensions, high connectivity degree, dynamically evolution over the time, which represent special challenges for efficient graph search methods, since they result in huge memory requirements, high branching factors, unknown dimensions and high cost for accessing nodes. The paper aims to discuss these issues.

Design/methodology/approach

– The proposed framework is based on the novel notion of heuristic semantic walk (HSW). In the HSW framework, a semantic proximity measure among concepts, reflecting the collective knowledge embedded in search engines or other statistical sources, is used as a heuristic in order to guide the search in the collaborative network. Different search strategies, information sources and proximity measures, can be used to adapt HSW to the collaborative semantic network under consideration.

Findings

– Experiments held on the Wikipedia network and Bing search engine on a range of different semantic measures show that the proposed HSW approach with weighted randomized walk strategy outperforms state-of-the-art search methods.

Originality/value

– To the best of the authors' knowledge, the proposed HSW model is the first approach which uses search engine-based proximity measures as heuristic for semantic search.
DGIST: a digital game for international students' adjustment
Authors: Bisadi Maryam , Y.K. Chua Alton
Published: April 2014

Purpose

– This paper aims to explore the use of digital game to help international student to acquire adjustment-related information.

Design/methodology/approach

– The study introduces a digital game called Digital Game for International Student Training (DGIST) which is intended to satisfy important aspects of international students' information needs. To evaluate the efficacy of DGIST, a before-and-after with control experimental design was adopted. The experimental group students were exposed to DGIST, while the control group was given a paper-based document. A total of 80 participants were involved in the study. They were from nine different countries with average age of 26. The analysis of covariance was used to analyze the data collected.

Findings

– Statistical analyses reveal that there was a significant difference between DGIST and paper-based document in helping international students acquire adjustment-related information on post-test score.

Originality/value

– Although digital games have been developed for various subject areas, little attention has been focused on using digital games to address international students' adjustment issues. This paper thus represents a step towards an uncharted research territory.
Turning theTitanic: inertia and the drivers of climate change education
Authors: J. Fahey Shireen , R. Labadie John , Meyers Noel
Published: April 2014

Purpose

– The aim of this paper is to present the challenges external drivers and internal inertia faced by curriculum designers and implementers at institutions of higher education. The challenges to academics from competing factors are presented: internal resistance to changing existing curricula vs the necessity to continuously evolve programmes to reflect a dynamic, uncertain future. The necessity to prepare future leaders to face global issues such as climate change, dictates changing curricula to reflect changing personal, environmental and societal needs.

Design/methodology/approach

– This paper uses the case study method to examine two models of climate change curriculum design and renewal. One model, from an Australian university, is based upon national education standards and the second is a non-standards-based curriculum design, developed and delivered by a partnership of four North American universities.

Findings

– The key findings from this study are that the highest level of participation by internal-to-the-programme academics and administrators is required. Programme quality, delivery and content alignment may be compromised with either stand-alone course delivery and learning outcomes, or if courses are developed independently of others in the programme. National educational standards can be effective tools to guide course and programme management, monitoring, review and updating.

Practical implications

– The paper includes implications for postgraduate level curricula design, implementation and programme evaluation.

Originality/value

– The paper is the first to compare, contrast and critique a national standards-based, higher education curriculum and a non-standards-based curriculum.
The effect of peer tutoring on academic achievement
Authors: Comfort Paul , James McMahon John
Published: April 2014

Purpose

– The purpose of this paper is to determine the effects of peer tutoring on the academic achievement, during practical assessments, of the tutors and tutees.

Design/methodology/approach

– Final year students on an undergraduate Sports Science degree programme provided optional peer tutored practical sessions, once per week (two hours per session) for 12 weeks, for second year students on the same undergraduate programme. Students were then assessed on their ability to demonstrate, coach and explain a range of dynamic resistance exercises.

Findings

– A one way analysis of variance with Bonferroni post hoc analysis demonstrated a significantly greater academic achievement in the peer tutoring group (73.64±10.26 per cent) compared to students that were not peer tutored (46.20±20.27, p=0.003) and compared to the previous years’ cohort that were not peer tutored (56.83±19.18, p<0.001). Moreover, tutors also demonstrated significantly (p<0.001) higher grades (82.00±11.01 per cent) compared to the students that did not act as peer tutors (64.88±8.82 per cent).

Practical implications

– This study demonstrates that peer tutoring during practical sessions in Sports Science programmes can enhance the development of practical skills and achievement of both tutees and tutors during practical assessments.

Originality/value

– To the authors knowledge this is the first study to determine the effects of peer tutoring on both the tutors and tutees, in a Sports Science setting.
Effectiveness of graduate programs in administrative and instructional leadership
Authors: Cozza Barbara , Blessinger Patrick , Mandracchia Marcella
Published: April 2014

Purpose

– The purpose of this paper is twofold: to assess the effectiveness of the school building and school district leadership programs within the School of Education at a large private university and to find areas for improvement in these programs.

Design/methodology/approach

– This study utilized a qualitative grounded theory research strategy using a case study approach of two campuses of the university. Each case study utilized the same data collection methods and data analysis procedures in order to increase validity.

Findings

– The key findings revealed that the graduates emphasized the importance of professional support via a cohort structure, a sound program philosophy, and a comprehensive and coherent curriculum. Recruitment and administrative internships were two effectiveness criteria not emphasized by the participants. Thus, the findings suggest the program could be enhanced by the creation of leadership portfolios and quality administrative internships. These findings are also consistent with the transfer of learning theory.

Research limitations/implications

– Educational leadership preparation programs continue to be highly relevant fields of study as society places greater expectations on school leaders for meeting learning outcomes and educational standards. Increased calls for accountability have initiated more research on conditions and other factors that lead to enhanced student learning in these programs. To the extent that other universities have similar programs in place, the findings may benefit them in developing or improving their own program(s).

Practical implications

– The paper includes implications for the development of innovative programs in administrative and instructional leadership. The findings of this study suggest the program could be enhanced by the creation of leadership portfolios (digital and non-digital) as a culminating experience to summarize accomplishments, demonstrate competencies, and to serve as an authentic form of assessment, as well as the creation of quality administrative internships to provide students with real-life opportunities while they go through the program.

Originality/value

– This paper fulfils an identified need to study those program characteristics that have been shown to have the strongest relationship to school improvement.
The nexus between corporate governance and records management in private and public hospitals in Ghana
Authors: Mensah Monica , Adams Musah
Published: April 2014

Purpose

– The purpose of this paper is to examine the relationship between corporate governance and records management in private and public hospitals in Ghana, with the aim of finding out how the effective and efficient management of a hospital's records can facilitate its governance obligations, which includes but not limited to accountability, transparency and information security.

Design/methodology/approach

– The study was informed by the triangulation of the Stakeholders' and Records Continuum Theories. Data used for analysis were drawn from 90 respondents from four hospitals with the use of questionnaires and personal observations. A total of 82 questionaries' were returned in their complete forms and used for the analysis. Linear regressions were performed to establish the relationship between corporate governance and records management.

Findings

– The key finding of the study was that, the hospitals generated different types of records in the course of their business activities but existing records management standards, practices and systems were inadequate and undermined the contribution records could make in support of the governance function in the hospitals. Results of a linear regression also revealed that positive and significant relationships exist between corporate governance and records management. Furthermore, all variables used as predictors of corporate governance had positive and significant relationships with records management except information security.

Research limitations/implications

– Participants were from four hospitals in only one Region in Ghana, and as such the results could not be generalised to the whole country.

Practical implications

– The study has established the recognition of the essential but often ignored conditions necessary for an effective and efficient governance system for hospitals.

Originality/value

– The study has demonstrated that the effective management of hospital records is a critical factor in providing capacity for hospitals' efficiency, accountability, transparency, information security and indeed good governance. This research has also contributed towards bridging the theoretical gap identified in the study.
Agile at IBM: software developers teach a new dance step to management
Authors: M. Randall Robert
Published: April 2014

Purpose

– Explains how companies that are seeking to implement rapid innovation can adopt the Agile software development approach. In Agile, self-organizing teams work in short cycles called “sprints” and develop the features to enable the product to continuously evolve in the light of the experience they gain and through customer feedback.

Design/methodology/approach

– For insight into how Agile is being implemented at a leading software services firm with clients in hundreds of industries, Strategy & Leadership asked Rob Purdie, Agile Practice Lead for the IBM Design Lab, how Agile software development methods were contributing to the success of IBM's key digital marketing initiatives.

Findings

– The traditional approach to software development is to define, design, develop and test everything – before delivering anything. With Agile, managers can reduce waste by prioritizing features based on relative business value, evaluating and re-designing as the project proceeds.

Practical implications

– Agile requires leaders and teams to work and learn through problems, designs and options in an open and transparent environment. It places new demands on technical leaders in terms of negotiation and planning skills.

Originality/value

– Managers outside the software industry should note that Agile/Scrum is likely to be increasingly essential to the future of product development and manufacturing. Nowadays many products for consumers and businesses include embedded software systems, so developing products in the future will require deeper collaboration across multiple engineering disciplines and marketing teams and familiarity with the Agile approach.
Anti‐quorum sensing activity of Psidium guajava L. flavonoids against Chromobacterium violaceum and Pseudomonas aeruginosa PAO1
Authors: Vasavi Halkare Suryanarayana , Arun Ananthapadmanabha Bhagwath , Rekha Punchapady‐Devasya
Published: April 2014

Psidium guajava L., which has been used traditionally as a medicinal plant, was explored for anti‐quorum sensing (QS) activity. The anti‐QS activity of the flavonoid (FL) fraction of P. guajava leaves was determined using a biosensor bioassay with Chromobacterium violaceum CV026. Detailed investigation of the effects of the FL‐fraction on QS‐regulated violacein production in C. violaceum ATCC12472 and pyocyanin production, proteolytic, elastolytic activities, swarming motility and biofilm formation in Pseudomonas aeruginosa PAO1 was performed using standard methods. Possible mechanisms of QS‐inhibition were studied by assessing violacein production in response to N‐acyl homoserine lactone (AHL) synthesis in the presence of the FL‐fraction in C. violaceum ATCC31532 and by evaluating the induction of violacein in the mutant C. violaceum CV026 by AHL extracted from the culture supernatants of C. violaceum 31532. Active compounds in the FL‐fraction were identified by liquid chromatography–mass spectrometry (LC–MS). Inhibition of violacein production by the FL‐fraction in a C. violaceum CV026 biosensor bioassay indicated possible anti‐QS activity. The FL‐fraction showed concentration‐dependent decreases in violacein production in C. violaceum 12472 and inhibited pyocyanin production, proteolytic and elastolytic activities, swarming motility and biofilm formation in P. aeruginosa PAO1. Interestingly, the FL‐fraction did not inhibit AHL synthesis; AHL extracted from cultures of C. violaceum 31532 grown in the presence of the FL‐fraction induced violacein in the mutant C. violaceum CV026. LC–MS analysis revealed the presence of quercetin and quercetin‐3‐O‐arabinoside in the FL‐fraction. Both quercetin and quercetin‐3‐O‐arabinoside inhibited violacein production in C. violaceum 12472, at 50 and 100 μg/mL, respectively. Results of this study provide scope for further research to exploit these active molecules as anti‐QS agents.
Time‐lapse pre‐stack seismic data registration and inversion for CO2 sequestration study at Cranfield
Authors: Zhang Rui , Song Xiaolei , Fomel Sergey , Sen Mrinal K , Srinivasan Sanjay
Published: April 2014

Pre‐stack seismic data are indicative of subsurface elastic properties within the amplitude versus offset characteristic and can be used to detect elastic rock property changes caused by injection. We perform time‐lapse pre‐stack 3‐D seismic data analysis for monitoring sequestration at Cranfield. The time‐lapse amplitude differences of Cranfield datasets are found entangled with time‐shifts. To disentangle these two characters, we apply a local‐correlation‐based warping method to register the time‐lapse pre‐stack datasets, which can effectively separate the time‐shift from the time‐lapse seismic amplitude difference without changing the original amplitudes. We demonstrate the effectiveness of our registration method by evaluating the inverted elastic properties. These inverted time‐lapse elastic properties can be reliably used for monitoring plumes.
User‐friendly and evidence‐based tool to evaluate probability of eradication of aquatic non‐indigenous species
Authors: Drolet David , Locke Andrea , Lewis Mark A. , Davidson Jeff
Published: April 2014

The gap between practitioners and conservation or environmental management science is difficult to bridge. Managers sometimes use limited scientific information in their decision‐making process, mainly because they have little time to review primary literature before making a decision. Making data readily available to managers is expected to improve the overall efficiency of management interventions. Here, we present an approach to develop user‐friendly applications for evidence‐based management and illustrate the concept by presenting a simple computer program designed to evaluate the probability of eradication of aquatic non‐indigenous species.

We conducted a review of case studies that attempted to control aquatic non‐indigenous species and used a statistical model to relate the outcome (eradication or non‐eradication) to characteristics of the populations and interventions conducted. Based on a few key variables, the model returned accurate probabilities of eradication as evaluated with a receiver operating characteristic curve and jackknife and cross‐validation procedures.

We packaged the statistical model in a user‐friendly computer program that can be used by managers to (i) rapidly calculate the probability of success of a planned intervention with associated uncertainty, (ii) compare the success probabilities of different possible interventions and (iii) prioritize what information should be collected to increase the reliability of estimates.

Synthesis and applications. Our decision support tool is easy to implement, statistically flexible and could be used for any type of conservation or management intervention, given a sufficient number of case studies available in the literature. We recommend that scientists develop such tools whenever they conduct reviews of effectiveness of intervention. This is likely to result in greater use of data by practitioners, increased reliability of cost–benefit analyses and an overall increase in efficiency in conservation and environmental management.
Host compatibility as a critical factor in management unit recognition: population‐level differences in mussel–fish relationships
Authors: Douda Karel , Sell Jerzy , Kubíková‐Peláková Lucie , Horký Pavel , Kaczmarczyk Agnieszka , Mioduchowska Monika
Published: April 2014

The recognition of management units (MUs) that respect interpopulation distinctions in management needs is central to many biological applications addressing species conservation, biological invasions and ecosystem processes.

We present a methodological approach for the evaluation of population‐level differences in the host compatibility of natural populations of affiliate (dependent) species. Two experiments were performed to diagnose the sources of variability in the relationships between an endangered freshwater mussel Unio crassus and its host fish species in a fragmented river system in Central Europe.

Despite the common approach applied to the conservation of U. crassus throughout the study area, we identified differences in the ability of U. crassus to infest particular host fish species between nearby and recently isolated mussel populations. These differences could strongly influence their reproductive success under a constant conservation regime.

The observed differences were accompanied by genetic and morphometric distinctions, as revealed by microsatellite, mtDNA and elliptic Fourier descriptor analyses. The genetic data indicated substantial reproductive isolation, which could have resulted in adaptive or random changes responsible for the differences in host compatibility.

We showed that experimental testing of physiological host compatibility can be effectively used for the detection of different MUs of U. crassus, with direct implications for the management of host populations. In combination with traditional genetic and morphometric techniques, this approach may provide a general framework for the recognition and care of management units of affiliate species.

Synthesis and applications. Population‐level evaluations of host compatibility should be utilized in management unit recognition and the formulation of management targets for affiliate species. We demonstrated that small‐scale cross‐compatibility testing can be effectively used to diagnose the sources of variability in host relationships with direct management implications. This approach can enhance the targeting of management actions in many biological applications addressing species conservation, biological invasions and ecosystem processes.
Prevalence of phylogenetic clustering at multiple scales in an African rain forest tree community
Authors: Parmentier Ingrid , Réjou‐Méchain Maxime , Chave Jérôme , Vleminckx Jason , Thomas Duncan W. , Kenfack David , Chuyong George B. , Hardy Olivier J.
Published: April 2014

In highly diverse ecosystems, such as tropical forests, the relative importance of mechanisms underlying species coexistence (e.g. habitat filtering, competitive exclusion, neutral dynamics) is still poorly known and probably varies depending on spatial and phylogenetic scales.

Here, we develop new approaches for dissecting simultaneously the phylogenetic structure of communities at different phylogenetic depths and spatial scales. We tested with simulations that our method is able to disentangle overdispersion and clustering effects occurring at contrasted phylogenetic depths.

We applied our approaches to a 50 ha Forest Dynamic Plot located in Korup National Park (Cameroon) where 329,000 tree stems ≥ 1 cm in diameter were identified and mapped, and using a newly generated dated molecular phylogenetic tree based on 2 plastid loci (rbcL and matK), including 272 species from Korup (97% of the individuals).

Significant patterns of phylogenetic turnover were detected across 20 × 20 m2 quadrats at most spatial scales, with higher turnover between topographic habitats than within habitats, indicating the prevalence of habitat filtering processes. Spatial phylogenetic clustering was detected over the entire range of phylogenetic depths indicating that competitive exclusion does not generate a pattern of phylogenetic overdispersion at this scale, even at a shallow phylogenetic depth.

Using an individual‐based approach, we also show that closely related species tended to aggregate spatially until a scale of 1 m. However, the signal vanishes at smaller distance, suggesting that competitive exclusion can balance the impact of environmental filtering at a very fine spatial scale.

Synthesis. Using new methods to characterize the structure of communities across spatial and phylogenetic scales, we inferred the relative importance of the mechanisms underlying species coexistence in tropical forests. Our analysis confirms that environmental filtering processes are key in the structuring of natural communities at most spatial scales. Although negative‐density tends to limit coexistence of closely related species at very short distance (<1 m), its influence is largely veiled by environmental filtering at larger distances.
Arsenic hypertolerance in the protist Euglena mutabilis is mediated by specific transporters and functional integrity maintenance mechanisms
Authors: Halter David , Andres Jérémy , Plewniak Frédéric , Poulain Julie , Da Silva Corinne , Arsène‐Ploetze Florence , Bertin Philippe N.
Published: April 2014

Arsenic is a toxic metalloid known to cause multiple and severe cellular damages, including lipid peroxidation, protein misfolding, mutagenesis and double and single‐stranded DNA breaks. Thus, exposure to this compound is lethal for most organisms but some species such as the photosynthetic protist Euglena mutabilis are able to cope with very high concentrations of this metalloid. Our comparative transcriptomic approaches performed on both an arsenic hypertolerant protist, i.e. E. mutabilis, and a more sensitive one, i.e. E. gracilis, revealed multiple mechanisms involved in arsenic tolerance. Indeed, E. mutabilis prevents efficiently the accumulation of arsenic in the cell through the expression of several transporters. More surprisingly, this protist induced the expression of active DNA reparation and protein turnover mechanisms, which allow E. mutabilis to maintain functional integrity of the cell under challenging conditions. Our observations suggest that this protist has acquired specific functions regarding arsenic and has developed an original metabolism to cope with acid mine drainages‐related stresses.
FDG PET in early stage cutaneous malignant melanoma
Authors: McIvor Jody , Siew Teck , Campbell Andrew , McCarthy Michael
Published: April 2014

Introduction

Fluorodeoxyglucose positron emission tomography (FDG PET) is not recommended in early stage melanoma; however, a significant number of cases are referred to our institution for FDG PET. We refer to early stage disease as American Joint Committee on Cancer (AJCC) stage I and II, which includes all cases without metastases. A retrospective review was undertaken to determine the clinical utility of FDG PET in this patient group.

Methods

A retrospective study of FDG scans on all patients presenting to the WA PET Centre with early stage melanoma over a 5½ year period was undertaken. The positivity rate of the initial study for detection of malignant melanoma was determined. In patients with an initially negative FDG PET, the time from initial diagnosis to a positive surveillance study was determined. Both the initial positivity rate and time to a positive study were correlated with Breslow staging.

Results

Three hundred twenty‐two patients were included in the study, of which 74 had initial positive FDG PET scans (23%). Adequate follow‐up was available in 51 patients with the PET result confirmed as true positive in 37 (positive predictive value 73%). One hundred eight of 248 patients initially negative had follow‐up scans during the follow‐up period, of which 48 became positive. The 73% of recurrences were over 12 months post‐diagnosis. No correlation with Breslow thickness was demonstrated.

Conclusion

Despite FDG PET not being recommended for early cutaneous malignant melanoma, 27% of melanoma cases referred for FDG PET during the study period were AJCC stage I or II. Our results suggest FDG PET in early stage melanoma demonstrates occult disease in 17% of cases.