bluuebunny/crossref_metadata_2025 huggingface dataset:
Resolving the Nucleus of Centaurus A at Mid-Infrared Wavelengths
Authors: Burtscher Leonard , Meisenheimer Klaus , Jaffe Walter , Tristram Konrad R. W. , Rottgering Huub J. A.
Published: October 2010

We have observed Centaurus A with the Mid-Infrared Interferometric Instrument (MIDI) at the Very Large Telescope Interferometer at resolutions of 7–15 mas (at 12.5 μm) and filled gaps in the (u, v) coverage in comparison to earlier measurements. We are now able to describe the nuclear emission in terms of geometric components and derive their parameters by fitting models to the interferometric data. With simple geometrical models, the best fit is achieved for an elongated disk with flat intensity profile with diameter 76 ± 9 × 35 ± 2 mas (1.41 ± 0.17 × 0.65 ± 0.03 pc) whose major axis is oriented at a position angle (PA) of 10.1 ± 2.2° east of north. A point source contributes 47 ± 11% of the nuclear emission at 12.5 μm. There is also evidence that neither such a uniform nor a Gaussian disk are good fits to the data. This indicates that we are resolving more complicated small-scale structure in active galactic nuclei with MIDI, as has been seen in Seyfert galaxies previously observed with MIDI. The PA and inferred inclination i = of the dust emission are compared with observations of gas and dust at larger scales.
The Warped Disk of Centaurus A from a Radius of 2 to 6500 pc
Authors: Quillen Alice C. , Neumayer Nadine , Oosterloo Tom , Espada Daniel
Published: October 2010

We compile position and inclination angles for tilted ring fits to the warped dusty and gaseous disk of Cen A, spanning a radius of 1.8 to 6500 pc, from recent observations. For radii exterior to 1 kpc, tilted-ring orientations lie on an arc, on a plot of polar-inclination versus position-angle, suggesting that precession following a merger can account for the ring morphology. Three kinks in the ring orientations are seen on the polar plot, the one at radius of about 1.3 kpc we suspect corresponds to the location where self-gravity in the disk affects the ring precession rate. Another at a radius of about 600 pc may be associated with a gap in the gas distribution. A third kink is seen at a radius of 100 pc. A constant inclination tilted disk precessing about the jet axis may describe the disk between 100 and 20 pc but not interior to this. A model with disk orientation matching the molecular circumnuclear disk at 100 pc that decays at smaller radii to an inner flat disk perpendicular to the jet may account for disk orientations within 100 pc. Neither model would account for the cusps or changes in disk orientation at 100 or 600 pc.
Facilitating recruitment of Amphibolis as a novel approach to seagrass rehabilitation in hydrodynamically active waters
Authors: Wear Rachel J. , Tanner Jason E. , Hoare Sonja L.
Published: October 2010

Worldwide, 29% of seagrass habitats have been lost over the past century. Compared with large-scale losses, successful restoration programs are usually only small scale (a few hectares). One area of significant seagrass loss (>5200 ha) is Adelaide, South Australia. Improvements to wastewater management have raised the possibility of rehabilitation in this area. Traditional methods of seagrass restoration are expensive and have had limited success owing to high wave energy. We investigated a range of biodegradable substrates, mostly made of hessian (burlap), to enhance Amphibolis recruitment as an alternative. After 5 weeks, 16 514 seedlings, or 157 seedlings m–2, had recruited. Survival declined over the following 12 months to 31.4%, and down to 7.2% after 3 years, in part as a result of breakdown of the hessian, and the wave-exposed nature of the sites. During the initial 12 months, above- and belowground biomass increased 2.6- and 6.4-fold, respectively. The technique may represent a non-destructive, cost-effective (<AU$10 000 ha–1) method to restore Amphibolis over large spatial scales and in areas that are hydrodynamically too active for traditional techniques, thus helping ameliorate some of the large-scale losses of seagrasses that have occurred globally.
The influence of solar radiation on hydrogen peroxide concentrations in freshwater
Authors: Rusak Steven A. , Richard Luc E. , Peake Barrie M. , Cooper William J. , Bodeker Greg E.
Published: October 2010

Hydrogen peroxide (H2O2) is the most stable of the reactive oxygen species produced by photochemical reactions in natural waters. To relate H2O2 concentrations to solar irradiance, we made daily measurements of H2O2 in the Water of Leith, a freshwater stream in Dunedin, New Zealand, and co-located continuous measurements of the intensity of solar radiation, from September 2003 to March 2006. A simple model in the form of a first-order differential equation was fitted to the measurements. The model describes the H2O2 concentrations over time by using photochemical production rates from ultraviolet-B (UVB), UVA and photosynthetically active radiation (PAR), and loss rates from temperature-dependent and temperature-independent processes. The retrieved model terms confirmed that H2O2 is produced by both UVB and UVA radiation. These results demonstrated that changes in solar radiation reaching the study site were closely correlated with the observed seasonal pattern in H2O2 concentrations in the water.
The politicisation of sexuality and rise of homosexual movements in post-colonial Cameroon
Authors: Awondo Patrick
Published: October 2010

The article analyses the emergence of ‘homosexual’ organisations in Cameroon. Originating in a controversy over lists of public figures ‘presumed to be homosexual’ published in three newspapers in 2006, it explores the link between a critical political analysis of the concept of homosexuality and the emergence of the homosexual movement in Cameroon. Two main organisations, the Association pour la
Défense des droits des homosexuels (the Association for the Defence of Homosexual Rights [ADEFHO]) and Alternatives-Cameroun, cover different areas of activity, one concerned with sexual rights and the other with sexual health. Their connectedness to the international systems in which such causes are categorised is analysed, and it is suggested that this connection operates as both a resource and a constraint. The role of the actors illustrates the political tensions at play: these include youth, organised collectively, who publicly reject homosexuality. The article sets out to give a critical analysis of the issues underlying this confrontation by demonstrating that it is also influenced by post-colonial tensions and their repercussions.
Rubicon and PLEKHM1 Negatively Regulate the Endocytic/Autophagic Pathway via a Novel Rab7-binding Domain
Authors: Tabata Keisuke , Matsunaga Kohichi , Sakane Ayuko , Sasaki Takuya , Noda Takeshi , Yoshimori Tamotsu
Published: October 2010

The endocytic and autophagic pathways are involved in the membrane trafficking of exogenous and endogenous materials to lysosomes. However, the mechanisms that regulate these pathways are largely unknown. We previously reported that Rubicon, a Beclin 1–binding protein, negatively regulates both the autophagic and endocytic pathways by unidentified mechanisms. In this study, we performed database searches to identify potential Rubicon homologues that share the common C-terminal domain, termed the RH domain. One of them, PLEKHM1, the causative gene of osteopetrosis, also suppresses endocytic transport but not autophagosome maturation. Rubicon and PLEKHM1 specifically and directly interact with Rab7 via their RH domain, and this interaction is critical for their function. Furthermore, we show that Rubicon but not PLEKHM1 uniquely regulates membrane trafficking via simultaneously binding both Rab7 and PI3-kinase.
The evolution of eusociality in allodapine bees: workers began by waiting
Authors: Schwarz Michael P. , Tierney Simon M. , Rehan Sandra M. , Chenoweth Luke B. , Cooper Steven J. B.
Published: October 2010

Understanding how sterile worker castes in social insects first evolved is one of the supreme puzzles in social evolution. Here, we show that in the bee tribe Allodapini, the earliest societies did not entail a foraging worker caste, but instead comprised females sharing a nest with supersedure of dominance. Subordinates delayed foraging until they became reproductively active, whereupon they provided food for their own brood as well as for those of previously dominant females. The earliest allodapine societies are, therefore, not consistent with an ‘evo-devo’ paradigm, where decoupling of foraging and reproductive tasks is proposed as a key early step in social evolution. Important features of these ancestral societies were insurance benefits for dominants, headstart benefits for subordinates and direct reproduction for both. The two lineages where morphologically distinct foraging worker castes evolved both occur in ecosystems with severe constraints on independent nesting and where brood rearing periods are very seasonally restricted. These conditions would have strongly curtailed dispersal options and increased the likelihood that dominance supersedure occurred after brood rearing opportunities were largely degraded. The origins of foraging castes, therefore, represented a shift towards assured fitness gains by subordinates, mediated by the dual constraints of social hierarchies and environmental harshness.
To breed or not to breed: a seabird's response to extreme climatic events
Authors: Cubaynes Sarah , Doherty Paul F. , Schreiber E. A. , Gimenez Olivier
Published: October 2010

Intermittent breeding is an important life-history strategy that has rarely been quantified in the wild and for which drivers remain unclear. It may be the result of a trade-off between survival and reproduction, with individuals skipping breeding when breeding conditions are below a certain threshold. Heterogeneity in individual quality can also lead to heterogeneity in intermittent breeding. We modelled survival, recruitment and breeding probability of the red-footed booby (
Sula sula
), using a 19 year mark–recapture dataset involving more than 11 000 birds. We showed that skipping breeding was more likely in El-Niño years, correlated with an increase in the local sea surface temperature, supporting the hypothesis that it may be partly an adaptive strategy of birds to face the trade-off between survival and reproduction owing to environmental constraints. We also showed that the age-specific probability of first breeding attempt was synchronized among different age-classes and higher in El-Niño years. This result suggested that pre-breeders may benefit from lowered competition with experienced breeders in years of high skipping probabilities.
Prediction of human protein–protein interaction by a mixed Bayesian model and its application to exploring underlying cancer-related pathway crosstalk
Authors: Xu Yan , Hu Wen , Chang Zhiqiang , DuanMu Huizi , Zhang Shanzhen , Li Zhenqi , Li Zihui , Yu Lili , Li Xia
Published: October 2010

Protein–protein interaction (PPI) prediction method has provided an opportunity for elucidating potential biological processes and disease mechanisms. We integrated eight features involving proteomic, genomic, phenotype and functional annotation datasets by a mixed model consisting of full connected Bayesian (FCB) model and naive Bayesian model to predict human PPIs, resulting in 40 447 PPIs which contain 2740 common PPIs with the human protein reference database (HPRD) by a likelihood ratio cutoff of 512. Then we applied them to exploring underlying pathway crosstalk where pathways were derived from the pathway interaction database. Two pathway crosstalk networks (PCNs) were constructed based on PPI sets. The PPI sets were derived from two different sources. One source was strictly the HPRD database while the other source was a combination of HPRD and PPIs predicted by our mixed Bayesian method. We demonstrated that PCNs based on the mixed PPI set showed much more underlying pathway interactions than the HPRD PPI set. Furthermore, we mapped cancer-causing mutated somatic genes to PPIs between significant pathway crosstalk pairs. We extracted highly connected clusters from over-represented subnetworks of PCNs, which were enriched for mutated gene interactions that acted as crosstalk links. Most of the pathways in top ranking clusters were shown to play important roles in cancer. The clusters themselves showed coherent function categories pertaining to cancer development.
Stimulus-responsive liquids for encapsulation storage and controlled release of drugs from nano-shell capsules
Authors: Chang Ming-Wei , Stride Eleanor , Edirisinghe Mohan
Published: October 2010

Drug-delivery systems with a unique capability to respond to a given stimulus can improve therapeutic efficacy. However, development of such systems is currently heavily reliant on responsive polymeric materials and pursuing this singular strategy limits the potential for clinical translation. In this report, with a model system used for drug-release studies, we demonstrate a new strategy: how a temperature-responsive non-toxic, volatile liquid can be encapsulated and stored under ambient conditions and subsequently programmed for controlled drug release without relying on a smart polymer. When the stimulus temperature is reached, controlled encapsulation of different amounts of dye in the capsules is achieved and facilitates subsequent sustained release. With different ratios of the liquid (perfluorohexane): dye in the capsules, enhanced controlled release with real-time response is provided. Hence, our findings offer great potential for drug-delivery applications and provide new generic insights into the development of stimuli drug-release systems.
Targeting vaccination against novel infections: risk, age and spatial structure for pandemic influenza in Great Britain
Authors: Keeling Matt J. , White Peter J.
Published: October 2010

The emergence of a novel strain of H1N1 influenza virus in Mexico in 2009, and its subsequent worldwide spread, has focused attention to the question of optimal deployment of mass vaccination campaigns. Here, we use three relatively simple models to address three issues of primary concern in the targeting of any vaccine. The advantages of such simple models are that the underlying assumptions and effects of individual parameters are relatively clear, and the impact of uncertainty in the parametrization can be readily assessed in the early stages of an outbreak. In particular, we examine whether targeting risk-groups, age-groups or spatial regions could be optimal in terms of reducing the predicted number of cases or severe effects; and how these targeted strategies vary as the epidemic progresses. We examine the conditions under which it is optimal to initially target vaccination towards those individuals within the population who are most at risk of severe effects of infection. Using age-structured mixing matrices, we show that targeting vaccination towards the more epidemiologically important age groups (5–14 year olds and then 15–24 year olds) leads to the greatest reduction in the epidemic growth and hence reduces the total number of cases. Finally, we consider how spatially targeting the vaccine towards regions of country worst affected could provide an advantage. We discuss how all three of these priorities change as both the speed at which vaccination can be deployed and the start of the vaccination programme is varied.
Collapse mechanism maps for a hollow pyramidal lattice
Authors: Pingle S. M. , Fleck N. A. , Deshpande V. S. , Wadley H. N. G.
Published: October 2010

Cellular materials with hollow lattice truss topologies exhibit higher compressive strengths than equivalent structures with solid trusses owing to their greater resistance to plastic buckling. Consequently, hollow trusses have attracted interest as the cores for sandwich panels. Finite-element calculations are used to investigate the elastic–plastic compressive collapse of a metallic sandwich core made from vertical or inclined circular tubes, made from annealed AISI 304 stainless steel. First, the dependence of the axial compressive collapse mode upon tube geometry is determined for vertical tubes with built-in ends and is displayed in the form of a collapse mechanism map. Second, the approach is extended to inclined circular hollow tubes arranged as a pyramidal lattice core; the collapse modes are identified and the peak compressive strength is determined as a function of geometry. For a given relative density of hollow pyramidal core, the inclined tube geometry that maximizes peak strength is identified. The predicted collapse modes and loads for the pyramidal core are in excellent agreement with measurements for the limited set of experimentally investigated geometries.
Primate extinction risk and historical patterns of speciation and extinction in relation to body mass
Authors: Matthews Luke J. , Arnold Christian , Machanda Zarin , Nunn Charles L.
Published: October 2010

Body mass is thought to influence diversification rates, but previous studies have produced ambiguous results. We investigated patterns of diversification across 100 trees obtained from a new Bayesian inference of primate phylogeny that sampled trees in proportion to their posterior probabilities. First, we used simulations to assess the validity of previous studies that used linear models to investigate the links between IUCN Red List status and body mass. These analyses support the use of linear models for ordinal ranked data on threat status, and phylogenetic generalized linear models revealed a significant positive correlation between current extinction risk and body mass across our tree block. We then investigated historical patterns of speciation and extinction rates using a recently developed maximum-likelihood method. Specifically, we predicted that body mass correlates positively with extinction rate because larger bodied organisms reproduce more slowly, and body mass correlates negatively with speciation rate because smaller bodied organisms are better able to partition niche space. We failed to find evidence that extinction rates covary with body mass across primate phylogeny. Similarly, the speciation rate was generally unrelated to body mass, except in some tests that indicated an increase in the speciation rate with increasing body mass. Importantly, we discovered that our data violated a key assumption of sample randomness with respect to body mass. After correcting for this bias, we found no association between diversification rates and mass.
Individual differences in plasticity and sampling when playing behavioural games
Authors: Morand-Ferron Julie , Varennes Elisabeth , Giraldeau Luc-Alain
Published: October 2010

When engaged in behavioural games, animals can adjust their use of alternative tactics until groups reach stable equilibria. Recent theory on behavioural plasticity in games predicts that individuals should differ in their plasticity or responsiveness and hence in their degree of behavioural adjustment. Moreover, individuals are predicted to be consistent in their plasticity within and across biological contexts. These predictions have yet to be tested empirically and so we examine the behavioural adjustment of individual nutmeg mannikins (Lonchura punctulata), gregarious ground-feeding passerines, when playing two different social foraging games: producer–scrounger (PS) and patch-choice (PC) games. We found: (i) significant individual differences in plasticity and sampling behaviour in each of the two games, (ii) individual differences in sampling behaviour were consistent over different test conditions within a game (PC) and over a six month period (PS), (iii) but neither individual plasticity nor sampling behaviour was correlated from one social foraging game to another. The rate at which birds sampled alternative tactics was positively associated with seed intake in PS trials but negatively associated in PC trials. These results suggest that games with frequency dependence of pay-offs can maintain differences in behavioural plasticity but that an important component of this plasticity is group- and/or context-specific.
Smells like aphids: orchid flowers mimic aphid alarm pheromones to attract hoverflies for pollination
Authors: Stökl Johannes , Brodmann Jennifer , Dafni Amots , Ayasse Manfred , Hansson Bill S.
Published: October 2010

Most insects are dependent on chemical communication for activities such as mate finding or host location. Several plants, and especially orchids, mimic insect semiochemicals to attract insects for unrewarded pollination. Here, we present a new case of pheromone mimicry found in the terrestrial orchidEpipactis veratrifolia. Flowers are visited and pollinated by several species of aphidophagous hoverflies, the females of which also often lay eggs in the flowers. The oviposition behaviour of these hoverflies is mainly guided by aphid-derived kairomones. We show that the flowers produce α- and β-pinene, β-myrcene and β-phellandrene, and that these compounds attract and induce oviposition behaviour in female hoverflies. This floral odour profile is remarkably similar to the alarm pheromone released by several aphid species, such asMegoura viciae. We therefore suggest thatE. veratrifoliamimics aphid alarm pheromones to attract hoverflies for pollination; this is the first time, to our knowledge, that such a case of mimicry has been demonstrated.
Nocardioides iriomotensis sp. nov., an actinobacterium isolated from forest soil
Authors: Yamamura Hideki , Ohkubo Shin-ya , Nakagawa Youji , Ishida Yuumi , Hamada Moriyuki , Otoguro Misa , Tamura Tomohiko , Hayakawa Masayuki
Published: October 2010

An actinomycete strain, designated IR27-S3T, was isolated from a forest soil sample collected from Iriomote Island, Okinawa, Japan. Cells of the isolate were Gram-stain-positive, aerobic, non-sporulating, non-motile coccoids or short rods. The strain grew in the presence of 0–7 % (w/v) NaCl, at pH 6–8 and at 12–37 °C, with optimum growth at 30 °C. Chemotaxonomically, the strain contained ll-diaminopimelic acid as the diagnostic diamino acid and MK-8(H4) as the predominant menaquinone. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unknown phospholipid. The major cellular fatty acids were iso-C16 : 0, C17 : 1
cis-9, C15 : 0 and iso-C15 : 0. The DNA G+C content was 73.7 mol%. On the basis of 16S rRNA gene sequence analysis, strain IR27-S3T was closely related to Nocardioides mesophilus MSL-22T (98.1 % 16S rRNA gene sequence similarity), Marmoricola bigeumensis MSL-05T (97.2 %) and Nocardioides jensenii DSM 20641T (96.5 %). On the basis of fatty acid analysis, phylogenetic analysis and phenotypic data, the isolate should be classified in a novel species of the genus Nocardioides, for which the name Nocardioides iriomotensis sp. nov. is proposed. The type strain is IR27-S3T ( = NBRC 105384T  = KACC 14926T).
Marinobacter oulmenensis sp. nov., a moderately halophilic bacterium isolated from brine of a salt concentrator
Authors: Kharroub Karima , Aguilera Margarita , Jiménez-Pranteda María Luján , González-Paredes Ana , Ramos-Cormenzana Alberto , Monteoliva-Sánchez Mercedes
Published: October 2010

A Gram-negative, aerobic, moderately halophilic bacterium, designated Set74T, was isolated from brine of a salt concentrator at Ain Oulmene, Algeria. The strain grew optimally at 37–40 °C, at pH 6.5–7.0 and with 5–7.5 % (w/v) NaCl and used various organic compounds as sole carbon, nitrogen and energy sources. Ubiquinone 9 (Q-9) was the major lipoquinone. The main cellular fatty acids were C16 : 0, C18 : 1ω9c, summed feature 7 (ECL 18.846; C19 : 0 cyclo ω10c and/or C19 : 1ω6c), C12 : 0 3-OH, C16 : 1ω9c, C18 : 0 and C12 : 0. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. The G+C content of the genomic DNA was 57.4 mol%. The 16S rRNA gene sequence analysis indicated that strain Set74T was a member of the genus Marinobacter. The closest relatives of strain Set74T were Marinobacter santoriniensis NKSG1T (97.5 % 16S rRNA gene sequence similarity) and Marinobacter koreensis DD-M3T (97.4 %). DNA–DNA relatedness between strain Set74T and M. santoriniensis DSM 21262T and M. koreensis DSM 17924T was 45 and 37 %, respectively. On the basis of the phenotypic, chemotaxonomic and phylogenetic features, a novel species, Marinobacter oulmenensis sp. nov., is proposed. The type strain is Set74T ( = CECT 7499T  = DSM 22359T).
Rhabdothermus arcticus gen. nov., sp. nov., a member of the family Thermaceae isolated from a hydrothermal vent chimney in the Soria Moria vent field on the Arctic Mid-Ocean Ridge
Authors: Steinsbu Bjørn O. , Tindall Brian J. , Torsvik Vigdis L. , Thorseth Ingunn H. , Daae Frida L. , Pedersen Rolf B.
Published: October 2010

A novel thermophilic member of the familyThermaceae, designated strain 2M70-1T, was isolated from the wall of an active white smoker chimney collected in the Soria Moria vent field at 71 °N in the Norwegian–Greenland Sea. Cells of the strain were Gram-negative, non-motile rods. Growth was observed at 37–75 °C (optimum 65 °C), at pH 6–8 (optimum pH 7.3) and in 1–5 % (w/v) NaCl (optimum 2.5–3.5 %). The isolate was aerobic but could also grow anaerobically using nitrate or elemental sulfur as electron acceptors. The strain was obligately heterotrophic, growing on complex organic substrates like yeast extract, Casamino acids, tryptone and peptone. Pyruvate, acetate, butyrate, sucrose, rhamnose and maltodextrin were used as complementary substrates. The G+C content of the genomic DNA was 68 mol%. Cells possessed characteristic phospholipids and glycolipids. Major fatty acids constituted saturated and unsaturated iso-branched and saturated anteiso-branched forms. Menaquinone 8 was the sole respiratory lipoquinone. Phylogenetic analysis of 16S rRNA gene sequences placed the strain in the familyThermaceaein the phylum‘Deinococcus–Thermus’, which is consistent with the chemotaxonomic data. On the basis of phenotypic and phylogenetic data, strain 2M70-1T( = JCM 15963T = DSM 22268T) represents the type strain of a novel species of a novel genus, for which the nameRhabdothermus arcticusgen. nov., sp. nov. is proposed.
Assessing the effect of the CLPG mutation on the microRNA catalog of skeletal muscle using high-throughput sequencing
Authors: Caiment Florian , Charlier Carole , Hadfield Tracy , Cockett Noelle , Georges Michel , Baurain Denis
Published: October 2010

The callipyge phenotype is a monogenic muscular hypertrophy that is only expressed in heterozygous sheep receiving the CLPG mutation from their sire. The wild-type phenotype of CLPG/CLPG animals is thought to result from translational inhibition of paternally expressed DLK1 transcripts by maternally expressed miRNAs. To identify the miRNA responsible for this trans effect, we used high-throughput sequencing to exhaustively catalog miRNAs expressed in skeletal muscle of sheep of the four CLPG genotypes. We have identified 747 miRNA species of which 110 map to the DLK1–GTL2 or callipyge domain. We demonstrate that the latter are imprinted and preferentially expressed from the maternal allele. We show that the CLPG mutation affects their level of expression in cis (∼3.2-fold increase) as well as in trans (∼1.8-fold increase). In CLPG/CLPG animals, miRNAs from the DLK1–GTL2 domain account for ∼20% of miRNAs in skeletal muscle. We show that the CLPG genotype affects the levels of A-to-I editing of at least five pri-miRNAs of the DLK1–GTL2 domain, but that levels of editing of mature miRNAs are always minor. We present suggestive evidence that the miRNAs from the domain target the ORF of DLK1, thereby causing the trans inhibition underlying polar overdominance. We highlight the limitations of high-throughput sequencing for digital gene expression profiling as a result of biased and inconsistent amplification of specific miRNAs.
An Arabidopsis Pentatricopeptide Repeat Protein, SUPPRESSOR OF VARIEGATION7, Is Required for FtsH-Mediated Chloroplast Biogenesis
Authors: Liu Xiayan , Yu Fei , Rodermel Steve
Published: October 2010

The Arabidopsis (Arabidopsis thaliana) yellow variegated2 (var2) mutant has green- and white-sectored leaves due to loss of VAR2, a subunit of the chloroplast FtsH protease/chaperone complex. Suppressor screens are a valuable tool to gain insight into VAR2 function and the mechanism of var2 variegation. Here, we report the molecular characterization of 004-003, a line in which var2 variegation is suppressed. We found that the suppression phenotype in this line is caused by lack of a chloroplast pentatricopeptide repeat (PPR) protein that we named SUPPRESSOR OF VARIEGATION7 (SVR7). PPR proteins contain tandemly repeated PPR motifs that bind specific RNAs, and they are thought to be central regulators of chloroplast and mitochondrial nucleic acid metabolism in plants. The svr7 mutant has defects in chloroplast ribosomal RNA (rRNA) processing that are different from those in other svr mutants, and these defects are correlated with reductions in the accumulation of some chloroplast proteins, directly or indirectly. We also found that whereas var2 displays a leaf variegation phenotype at 22°C, it has a pronounced chlorosis phenotype at 8°C that is correlated with defects in chloroplast rRNA processing and a drastic reduction in chloroplast protein accumulation. Surprisingly, the cold-induced phenotype of var2 cannot be suppressed by svr7. Our results strengthen the previously established linkage between var2 variegation and chloroplast rRNA processing/chloroplast translation, and they also point toward the possibility that VAR2 mediates different activities in chloroplast biogenesis at normal and chilling temperatures.
Evidence for the Existence of One Antenna-Associated, Lipid-Dissolved and Two Protein-Bound Pools of Diadinoxanthin Cycle Pigments in Diatoms
Authors: Lepetit Bernard , Volke Daniela , Gilbert Matthias , Wilhelm Christian , Goss Reimund
Published: October 2010

We studied the localization of diadinoxanthin cycle pigments in the diatoms Cyclotella meneghiniana and Phaeodactylum tricornutum. Isolation of pigment protein complexes revealed that the majority of high-light-synthesized diadinoxanthin and diatoxanthin is associated with the fucoxanthin chlorophyll protein (FCP) complexes. The characterization of intact cells, thylakoid membranes, and pigment protein complexes by absorption and low-temperature fluorescence spectroscopy showed that the FCPs contain certain amounts of protein-bound diadinoxanthin cycle pigments, which are not significantly different in high-light and low-light cultures. The largest part of high-light-formed diadinoxanthin cycle pigments, however, is not bound to antenna apoproteins but located in a lipid shield around the FCPs, which is copurified with the complexes. This lipid shield is primarily composed of the thylakoid membrane lipid monogalactosyldiacylglycerol. We also show that the photosystem I (PSI) fraction contains a tightly connected FCP complex that is enriched in protein-bound diadinoxanthin cycle pigments. The peripheral FCP and the FCP associated with PSI are composed of different apoproteins. Tandem mass spectrometry analysis revealed that the peripheral FCP is composed mainly of the light-harvesting complex protein Lhcf and also significant amounts of Lhcr. The PSI fraction, on the other hand, shows an enrichment of Lhcr proteins, which are thus responsible for the diadinoxanthin cycle pigment binding. The existence of lipid-dissolved and protein-bound diadinoxanthin cycle pigments in the peripheral antenna and in PSI is discussed with respect to different specific functions of the xanthophylls.
Commitment to purpose – the catalyst for organisation change and performance
Authors: Pritchard Neville
Published: October 2010

Purpose

To demonstrate the significance ensuring the clarity and alignment of purpose to the achievement of organisation goals.

Design/methodology/approach

Through experience of working within a number of organisations across varied industries the author has formulated a link between the extent to which interpretation of organisation purpose is aligned within functional and individual objectives and the achievement of organisational goals. This paper intends to provide a series of checks and a framework of audit that ensures that an organisation can consider the extent of consistency and inform management of the potential for improvement.

Findings

The consideration that a consistent interpretation and deployment of organisation purpose can serve as a catalyst of well‐implemented change and achievement of intent. The extent of potential negative impact and the potential sources of disengagement can be identified through investigation of ten questions. The potential to address issues from within a considered framework of review will enable improved consistency and application.

Practical implications

Improved approaches to the monitoring of aligned and integrated business unit, functional, team and individual objectives will provide a greater potential for organisation initiative success.

Originality/value

The structured review of the extent of alignment and integration will provide valuable information on the potential success of strategic initiatives, operational improvement projects and organisation vision. It is valuable to heads of HR, Learning and Development, executive, senior and middle management involved in change and the achievement of strategy and vision.
Utilization of color change in the condition monitoring of synthetic hydraulic oils
Authors: Victor Ossia Chinwuba , Hosung Kong , Markova Lyiubov V.
Published: October 2010

Purpose

The purpose of this paper is to present an optical technique for the condition monitoring of synthetic hydraulic oil; a deviation from the current techniques based on electrical principles which could be masked by wear particles and polar contaminants in oil.

Design/methodology/approach

Color‐change detecting device was developed using light‐emitting diodes, optic fibers and photodiodes of three‐color‐sensing elements. Color ratio (CR) and total contamination parameters based on transmitted light intensity in red, green, and blue wavelengths were used for oil chemical and particulate contamination assessment.

Findings

CR criterion was found independent of the particulate contamination of oil; but depended on chemical degradation. Total contamination index of the device depended on both the chemical degradation and particulate contamination of the oil, being most sensitive in blue wavelength, and least in the red. Test results for synthetic hydraulic oils monitored corroborated with results of viscosity, total acid number, RDE emission spectrometry, particulate counts and UV‐Vis photospectrometry. CR showed a clearer indication of oil degradation, compared to key monitoring parameters such as total acid number, viscosity, RDE emission spectrometry and particle counts.

Originality/value

This paper demonstrates how oil chemical degradation and total contamination could be detected through the device, before incipient wear occurs at tribological interfaces. The results showed that the color‐change parameters are effective criteria for the condition monitoring of synthetic hydraulic oils.
The effect of natural frequency of the experimental set‐up on the wear rate
Authors: Asaduzzaman Chowdhury Mohammad
Published: October 2010

Purpose

The purpose of this paper is to investigate experimentally the effect of natural frequency of the experimental set‐up on wear rate of glass fiber‐reinforced plastic (GFRP).

Design/methodology/approach

Experimental and dimensional analysis. A pin‐on‐disc apparatus having facility of vibrating the test samples at different directions, amplitudes and frequencies was designed and fabricated. The natural frequency of the set‐up was varied by adding dead loads of the set‐up from 0 to 50 kg. At each added load, the wear rate has been measured.

Findings

The presence of natural frequency of vibration indeed affects the wear rate considerably. The values of wear rate increase with the increase of natural frequency of vibration of the experimental set‐up. As the wear rate increases with increasing natural frequency of vibration, therefore, maintaining appropriate level of natural frequency vibration wear may be kept to some lower value to improve mechanical processes. The empirical formula of wear rate is derived from the dimensionless analysis. The wear rate obtained from the correlation shows better relationship with experimental results.

Practical implications

It is expected that the applications of these results will contribute to the improvement of different concerned mechanical systems and machines.

Originality/value

Considering the lack of correlation among wear rate, natural frequency of the experimental set‐up and other operating parameters, the present research was started to find out suitable correlation and a way of reducing wear rate by applying known natural frequency of vibration at a particular direction. Therefore, in this paper, an attempt is made to investigate the wear behavior of GFRP under natural frequency of the experimental set‐up. It is expected that the applications of these results will contribute to the improvement of different concerned mechanical systems.
Learning, experienced emotions, relationships and innovation in HRD
Authors: Anderson Valerie , Gilmore Sarah
Published: October 2010

Purpose

This paper aims to explore the introduction of a new experience‐based learning process in the learning and teaching of human resource development (HRD) within a professionally accredited curriculum in a UK University.

Design/methodology/approach

An action enquiry approach is taken, and qualitative data gathered over a full academic year from tutors and students are analysed to examine how those involved made sense of and learned about HRD.

Findings

Influences on the experience of an innovative HRD pedagogy are identified as: assessment processes and expectations; relationships and behaviours within the learning and teaching process; the experienced emotions of those involved; and the extent to which students feel clarity about what is expected.

Research limitations/implications

The qualitative nature of the data and the focus on one particular UK institutional taught module limits the generalisability; in particular, the experience of full‐time students or those involved in courses that focus exclusively on HRD outside of UK are not incorporated.

Practical implications

Attention to assessment processes is an essential pre‐requisite to any pedagogic innovation, as is effective and transparent team‐working by tutors and careful thought about tutor behaviours in settings where experienced emotions and relationships directly affect the innovative process.

Originality/value

The inherent tension between the constructivist and exploratory HRD curriculum and the requirement for “performative clarity” in HRD pedagogy is explored. Experienced emotions and relationships are shown to mediate a student‐centred and critically reflexive HRD pedagogy, something that is currently insufficiently recognised in much of the literature.
Modern learning methods for HRD
Authors: Wootton Danielle , Stone Barras Kenneth
Published: October 2010

Purpose

The purpose of this paper is to explore how professional skills training in making ethical decisions for redundancy selection, can be utilised though interactive role play, in a virtual learning environment.

Design/methodology/approach

A pilot study was undertaken with a group of part time mature students pursuing a professional development programme. The pilot was based on the CLE concept using a virtual learning environment (VLE) and involved ethical decision making in a redundancy scenario. Data was gathered through the VLE “log” and through a focus group interview.

Findings

Evidence is provided of the suitability of the CLE approach in this context. Additionally, the findings suggest that the use of a virtual learning environment for CLE raises a number of different issues for the management and motivation of participants. Virtual interaction of this nature creates different timescales, degrees of confidence and levels of anonymity than found with more traditional face‐to‐face training. This has an impact on behaviour and requires recognition and management by HRD facilitators.

Research limitations/implications

The study was based on a small‐scale pilot and has not been retested.

Practical implications

The findings provide practical implications for further design in using CLE in redundancy selection. Furthermore, clinics for a variety of scenarios both in the workplace and educational settings could be based on this approach.

Originality/value

The paper provides discussion of an innovative approach in an HRD context. These concepts have been not used extensively in the HRD field when trying to address learning and skills development in ethical decision making in practice.
The online oxymoron: teaching HRD through an impersonal medium
Authors: Callahan Jamie
Published: October 2010

Purpose

This paper aims to present an alternative and critical view of online learning for and by HRD professionals.

Design/methodology/approach

This paper is positioned as a conceptual reflection regarding practical implications not frequently considered with regard to implementing online learning systems.

Findings

This paper contends that many of the practical reasons for implementing online learning (accessibility, power equalization, and cost reduction) have fatal flaws.

Research limitations/implications

This paper suggests that researchers broaden their perspectives beyond the assumption that using online learning is the goal to be achieved with regard to teaching and learning HRD. Both traditional and critical perspectives of online learning should be more thoroughly explored through empirical research.

Originality/value

Few conceptual or empirical works challenge the unquestioned hegemony of the appeal of online learning, especially within the field of HRD. This reflection will hopefully serve as a catalyst for research that challenges unquestioned assumptions about online learning as a cutting edge innovation for teaching and learning HRD.
Toward an understanding of consumer perspectives on experiences
Authors: Baron Steve , Harris Kim
Published: October 2010

Purpose

The purpose of this paper is to offer a consumer‐centric perspective on experiences and interactions that is consistent with the foundational premises of the service‐dominant logic of marketing, and which incorporates an increased understanding of the value derived from consumer‐to‐consumer (C2C) interactions.

Design/methodology/approach

The paper offers a reoriented framework and process consumer experience modeling (CEM) for analyzing consumer interactions in experience domains. CEM uses qualitative analysis methods and software, underpinned by constructs relating to first‐, second‐ and third‐order interactions undertaken by consumers. It is illustrated with reference to the “gap year travel” experience domain.

Findings

The approach offers a means for identifying value enhancers and inhibitors for consumers. It provides, for organizations, a representation of consumer perspectives on interactions, giving due regard to C2C interactions. The example of the gap year travel experience demonstrates how this information can be used to inform the nature and emphasis of future marketing initiatives of organizations that are operating within the experience domain.

Research limitations/implications

The framework and some of its key concepts require verification in other experience domains to test their robustness. The increased availability of consumer “voice” data (via blogs, etc.) offers great opportunities for the development of consumer‐centric approaches to experience analysis.

Originality/value

This work represents one of the first reported attempts to adopt an empirical approach to issues that have been raised by the foundational premises of the service‐dominant logic of marketing, and consider, and provide a structure to interactions and experiences from a consumer perspective.
Causes for complaining behaviour intentions: the moderator effect of previous customer experience of the restaurant
Authors: Moliner Velázquez Beatriz , Fuentes Blasco María , Gil Saura Irene , Berenguer Contrí Gloria
Published: October 2010

Purpose

The purpose of this paper is to examine the main causes for complaining behaviour intentions expressed in three dimensions: private response, complaining response and complaining to third parties. The objectives are, first to study the direct influence of a set of antecedents and complaining behaviour intentions and second, to analyse the moderator effect of previous restaurant experience on subsequent relations.

Design/methodology/approach

A quantitative research method was used based on a self‐administered ad‐hoc questionnaire on a sample of 388 individuals who remembered an unsatisfactory experience in a restaurant.

Findings

The results show that the following variables have significant effects on intentions: attitudes towards complaining, level of information and complaining experience, level of dissatisfaction and likelihood of success with the complaint. An increased effect of attitudes towards complaining has been found in customers with no previous experience of the restaurant.

Originality/value

This work shows that the customer's previous experience is important in the formation of complaining behaviour intentions and therefore research is needed on new variables which may play a moderator role.
Quality management benchmarking: FDA compliance in pharmaceutical industry
Authors: Jochem Roland , Landgraf Katja
Published: October 2010

Purpose

By analyzing and comparing industry and business best practice, processes can be optimized and become more successful mainly because efficiency and competitiveness increase. This paper aims to focus on some examples.

Design/methodology/approach

Case studies are used to show knowledge exchange in the pharmaceutical industry. Best practice solutions were identified in two companies using a benchmarking method and five‐stage model.

Findings

Despite large administrations, there is much potential regarding business process organization. This project makes it possible for participants to fully understand their business processes. The benchmarking method gives an opportunity to critically analyze value chains (a string of companies or players working together to satisfy market demands for a special product).

Practical implications

Knowledge exchange is interesting for companies that like to be global players. Benchmarking supports information exchange and improves competitive ability between different enterprises. Findings suggest that the five‐stage model improves efficiency and effectiveness. Furthermore, the model increases the chances for reaching targets. The method gives security to partners that did not have benchmarking experience.

Originality/value

The study identifies new quality management procedures. Process management and especially benchmarking is shown to support pharmaceutical industry improvements.