bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of the sodiation/de-sodiation stability of Sn(C) by electrochemically inactive Na2Se
Authors: Dang Hoang X. , Meyerson Melissa L. , Heller Adam , Mullins C. Buddie
Published: September 2015

The cycling stability of similarly made Sn : C electrodes improves when Se, present as non-cycling Na2Se, is added.
A non-equilibrium state diagram for liquid/fluid/particle mixtures
Authors: Velankar Sachin S.
Published: September 2015

The equilibrium microstructures of ternary oil/water/surfactant mixtures are often classified within a triangular prism. This paper proposes a similar classification for non-equilibrium ternary liquid/fluid/particle mixtures. Distinct microstructures appear in different regions of the prism.
Nanostructured CuP2/C composites as high-performance anode materials for sodium ion batteries
Authors: Zhao Feipeng , Han Na , Huang Wenjing , Li Jiaojiao , Ye Hualin , Chen Fengjiao , Li Yanguang
Published: September 2015

CuP2/C composites obtained by high energy ball milling demonstrate potential as the anode material for sodium ion batteries.
Liquid-crystalline ionic liquids modified conductive polymers as a transparent electrode for indium-free polymer solar cells
Authors: Xiao Shuqin , Liu Cong , Chen Lie , Tan Licheng , Chen Yiwang
Published: September 2015

Ordered microstructure and high conductivity of poly(3,4-ethylenedioxythiophene):poly-(styrene sulfonate) films for transparent anode were obtained by liquid-crystalline ionic liquids modification.
Eye-friendly reduced graphene oxide circuits with nonlinear optical transparency on flexible poly(ethylene terephthalate) substrates
Authors: Yung Winco K. C. , Li Guijun , Liem Hai Ming , Choy Hang Shan , Cai Zhixiang
Published: September 2015

The fabrication of eye-friendly transparent microcircuitry patterned and reduced on graphene oxide using an industrial grade 1064 nm laser.
Protective effects of lithium against lead-induced toxicities in multiple systems of adult mouse
Authors: Wang Jiutao , Song Lingzhen , Li Kaikai , Yan Runchuan , Hu Xinde , Zhang Wei , Yin Yupeng , Zhao Shanting
Published: September 2015

Occupational and environmental exposures to lead (Pb), one of the toxic metal pollutants, is of global concern.
Increased expression of bone morphogenetic protein-7 and its related pathway provides an anti-fibrotic effect on silica induced fibrosis in vitro
Authors: Liang Di , Wang Yan , Zhu Zhonghui , Yang Gengxia , An Guoliang , Li Xiaoli , Niu Piye , Chen Li , Tian Lin
Published: September 2015

BMP-7 exerts an inhibitory effect on silica induced fibrosis in RLE-6TN cells via suppressing TGF-β signaling and activating BMP signaling.
Quinoid derivatives of the nevirapine metabolites 2-hydroxy- and 3-hydroxy-nevirapine: activation pathway to amino acid adducts
Authors: Harjivan Shrika G. , Pinheiro Pedro F. , Martins Inês L. , Godinho Ana L. , Wanke Riccardo , Santos Pedro P. , Pereira Sofia A. , Beland Frederick A. , Marques M. Matilde , Antunes Alexandra M. M.
Published: September 2015

Quinoid electrophiles from the nevirapine metabolites, 2-OH- and 3-OH-nevirapine, react with nitrogen-based bionucleophiles yielding covalent adducts.
Role of N-glycosylation in renal betaine transport
Authors: Schweikhard Eva S. , Burckhardt Birgitta C. , Joos Friedericke , Fenollar-Ferrer Cristina , Forrest Lucy R. , Kempson Stephen A. , Ziegler Christine
Published: September 2015

The osmolyte and folding chaperone betaine is transported by the renal Na+-coupled GABA (γ-aminobutyric acid) symporter BGT-1 (betaine/GABA transporter 1), a member of the SLC6 (solute carrier 6) family. Under hypertonic conditions, the transcription, translation and plasma membrane (PM) insertion of BGT-1 in kidney cells are significantly increased, resulting in elevated betaine and GABA transport. Re-establishing isotonicity involves PM depletion of BGT-1. The molecular mechanism of the regulated PM insertion of BGT-1 during changes in osmotic stress is unknown. In the present study, we reveal a link between regulated PM insertion and N-glycosylation. Based on homology modelling, we identified two sites (Asn171 and Asn183) in the extracellular loop 2 (EL2) of BGT-1, which were investigated with respect to trafficking, insertion and transport by immunogold-labelling, electron microscopy (EM), mutagenesis and two-electrode voltage clamp measurements in Xenopus laevis oocytes and uptake of radiolabelled substrate into MDCK (Madin–Darby canine kidney) and HEK293 (human embryonic kidney) cells. Trafficking and PM insertion of BGT-1 was clearly promoted by N-glycosylation in both oocytes and MDCK cells. Moreover, association with N-glycans at Asn171 and Asn183 contributed equally to protein activity and substrate affinity. Substitution of Asn171 and Asn183 by aspartate individually caused no loss of BGT-1 activity, whereas the double mutant was inactive, suggesting that N-glycosylation of at least one of the sites is required for function. Substitution by alanine or valine at either site caused a dramatic loss in transport activity. Furthermore, in MDCK cells PM insertion of N183D was no longer regulated by osmotic stress, highlighting the impact of N-glycosylation in regulation of this SLC6 transporter.
Expression profiles of miRNAs and involvement ofmiR-100andmiR-34in regulation of cell cycle arrest inArtemia
Authors: Zhao Ling-Ling , Jin Feng , Ye Xiang , Zhu Lin , Yang Jin-Shu , Yang Wei-Jun
Published: September 2015

Regulation of the cell cycle is complex but critical for proper development, reproduction and stress resistance. To survive unfavourable environmental conditions, the crustacean Artemia produces diapause embryos whose metabolism is maintained at extremely low levels. In the present study, the expression profiles of miRNAs during Artemia diapause entry and termination were characterized using high-throughput sequencing. A total of 13 unclassified miRNAs and 370 miRNAs belonging to 87 families were identified; among them, 107 were differentially expressed during diapause entry and termination. We focused on the roles of two of these miRNAs, miR-100 and miR-34, in regulating cell cycle progression; during the various stages of diapause entry, these miRNAs displayed opposing patterns of expression. A functional analysis revealed that miR-100 and miR-34 regulate the cell cycle during diapause entry by targeting polo-like kinase 1 (PLK1), leading to activation of the mitogen-activated protein kinase kinase-extracellular signal-regulated kinase-ribosomal S6 kinase 2 (MEK-ERK-RSK2) pathway and cyclin K, leading to suppression of RNA polymerase II (RNAP II) activity respectively. The findings presented in the present study provide insights into the functions of miR-100 and miR-34 and suggest that the expression profiles of miRNAs in Artemia can be used to characterize their functions in cell cycle regulation.
Biased signalling: the instinctive skill of the cell in the selection of appropriate signalling pathways
Authors: Liu Ying , Yang Yang , Ward Richard , An Su , Guo Xiao-Xi , Li Wei , Xu Tian-Rui
Published: September 2015

GPCRs (G-protein-coupled receptors) are members of a family of proteins which are generally regarded as the largest group of therapeutic drug targets. Ligands of GPCRs do not usually activate all cellular signalling pathways linked to a particular seven-transmembrane receptor in a uniform manner. The fundamental idea behind this concept is that each ligand has its own ability, while interacting with the receptor, to activate different signalling pathways (or a particular set of signalling pathways) and it is this concept which is known as biased signalling. The importance of biased signalling is that it may selectively activate biological responses to favour therapeutically beneficial signalling pathways and to avoid adverse effects. There are two levels of biased signalling. First, bias can arise from the ability of GPCRs to couple to a subset of the available G-protein subtypes: Gαs, Gαq/11, Gαi/o or Gα12/13. These subtypes produce the diverse effects of GPCRs by targeting different effectors. Secondly, biased GPCRs may differentially activate G-proteins or β-arrestins. β-Arrestins are ubiquitously expressed and function to terminate or inhibit classic G-protein signalling and initiate distinct β-arrestin-mediated signalling processes. The interplay of G-protein and β-arrestin signalling largely determines the cellular consequences of the administration of GPCR-targeted drugs. In the present review, we highlight the particular functionalities of biased signalling and discuss its biological effects subsequent to GPCR activation. We consider that biased signalling is potentially allowing a choice between signalling through ‘beneficial’ pathways and the avoidance of ‘harmful’ ones.
The sequence Pro295–Thr311 of the hinge region of oestrogen receptor α is involved in ERK1/2 activation via GPR30 in leiomyoma cells
Authors: Leiber Denis , Burlina Fabienne , Byrne Cillian , Robin Philippe , Piesse Christophe , Gonzalez Lucie , Leclercq Guy , Tanfin Zahra , Jacquot Yves
Published: September 2015

The ERα (oestrogen receptor α)-derived peptide ERα17p activates rapid signalling events in breast carcinoma cells under steroid-deprived conditions. In the present study, we investigated its effects in ELT3 leiomyoma cells under similar conditions. We show that it activates ERK1/2 (extracellular-signal-regulated kinase 1/2), the Gαi protein, the trans-activation of EGFR (epidermal growth factor receptor) and, finally, cell proliferation. It is partially internalized in cells and induces membrane translocation of β-arrestins. The activation of ERK1/2 is abolished by the GPR30 (G-protein-coupled receptor 30) antagonist G15 and GPR30 siRNA. When ERα is down-regulated by prolonged treatment with E2 (oestradiol) or specific ERα siRNA, the peptide response is blunted. Thus the simultaneous presence of GPR30 and ERα is required for the action of ERα17p. In addition, its PLM sequence, which interferes with the formation of the ERα–calmodulin complex, appears to be requisite for the phosphorylation of ERK1/2 and cell proliferation. Hence ERα17p is, to our knowledge, the first known peptide targeting ERα–GPR30 membrane cross-talk and the subsequent receptor-mediated biological effects.
Dissecting signalling by individual Akt/PKB isoforms, three steps at once
Authors: Osorio-Fuentealba Cesar , Klip Amira
Published: September 2015

The serine/threonine kinase Akt/PKB (protein kinase B) is key for mammalian cell growth, survival, metabolism and oncogenic transformation. The diverse level and tissue expression of its three isoforms, Akt1/PKBα, Akt2/PKBβ and Akt3/PKBγ, make it daunting to identify isoform-specific actions in vivo and even in isolated tissues/cells. To date, isoform-specific knockout and knockdown have been the best strategies to dissect their individual overall functions. In a recent article in the Biochemical Journal, Kajno et al. reported a new strategy to study isoform selectivity in cell lines. Individual Akt/PKB isoforms in 3T3-L1 pre-adipocytes are first silenced via shRNA and stable cellular clones lacking one or the other isoform are selected. The stably silenced isoform is then replaced by a mutant engineered to be refractory to inhibition by MK-2206 (Akt1W80A or Akt2W80A). Akt1W80A or Akt2W80A are functional and effectively recruited to the plasma membrane in response to insulin. The system affords the opportunity to acutely control the activity of the endogenous non-silenced isoform through timely addition of MK-2206. Using this approach, it is confirmed that Akt1/PKBα is the preferred isoform sustaining adipocyte differentiation, but both Akt1/PKBα and Akt2/PKBβ can indistinctly support insulin-dependent FoxO1 (forkhead box O1) nuclear exclusion. Surprisingly, either isoform can also support insulin-dependent glucose transporter (GLUT) 4 translocation to the membrane, in contrast with the preferential role of Akt2/PKBβ assessed by knockdown studies. The new strategy should allow analysis of the plurality of Akt/PKB functions in other cells and in response to other stimuli. It should also be amenable to high-throughput studies to speed up advances in signal transmission by this pivotal kinase.
GA signalling and cross-talk with other signalling pathways
Authors: Lor Vai S. , Olszewski Neil E.
Published: September 2015

Gibberellins (GAs) are phytohormones that regulate growth and development. DELLA proteins repress GA responses. GA binding to its receptor triggers a series of events that culminate in the destruction of DELLA proteins by the 26S proteasome, which removes the repression of GA signalling. DELLA proteins are transcription co-activators that induce the expression of genes which encode products that inhibit GA responses. In addition to repressing GA responses, DELLA proteins influence the activity of other signalling pathways and serve as a central hub from which other pathways influence GA signalling. In this role, DELLA proteins bind to and inhibit proteins, including transcription factors that act in the signalling pathways of other hormones and light. The binding of these proteins to DELLA proteins also inhibits DELLA activity. GA signalling is subject to homoeostatic regulation through GA-induced repression of GA biosynthesis gene expression, and increased production of the GA receptor and enzymes that catabolize bioactive GAs. This review also discusses the nature of mutant DELLA alleles that are used to produce high-yielding ‘Green Revolution’ cereal varieties, and highlights important gaps in our knowledge of GA signalling.
Improving Strategic Flexibility with Information Technologies: Insights for Firm Performance in an Emerging Economy
Authors: Chen Yang , Wang Yi , Nevo Saggi , Benitez Jose , Kou Gang
Published: September 2015

As the business environment becomes more turbulent, firms ponder how to become more flexible in reallocating or reconfiguring resources, processes, and strategies to respond more efficiently and effectively. In this context, the question of whether and how information technology (IT) can support strategic flexibility remains unresolved. This paper theorizes that firms that use IT to support core competencies will experience improved strategic flexibility, which may enhance their performance. It further theorizes that these effects are contingent on the form and nature of the firm's IT infrastructure, as well as its type of ownership - state-owned or private. Using data from a matched survey of IT and business executives in 148 Chinese manufacturing firms, we reveal positive, significant links between IT support for core competencies and strategic flexibility, and between strategic flexibility and firm performance. The findings further show that the effect of IT support for core competencies on performance is partially mediated by strategic flexibility, and that IT infrastructure positively moderates the link between IT support for core competencies and strategic flexibility. We also demonstrate that state-owned firms are less likely to apply IT applications to collect and analyse market information and thus surrender opportunities for achieving strategic flexibility and stronger firm performance.
Single-electron tunneling by using a two-dimensional Corbino nano-scale disk
Authors: Taira H. , Suzuki A.
Published: September 2015

We investigate a single-electron tunneling effect of two-dimensional electron systems formed in the Corbino nano-scale disk. By controlling bias and gate voltages, the transistor using this effect is able to control electrons one by one. The present study focuses on the electronic transmission probability affected by the charging energy in the Corbino-type single-electron transistor. We reformulated the Schrödinger equation for an electron in the Corbino disk in order to consider the effect of the curvature of the disk, taking into account the charging effect on the performance of the Corbino-type single-electron transistor. We formulated the transmission probability of the electron by applying the Wentzel-Kramers-Brillouin (WKB) method. The electron’s energy in the formula of the transmission probability is then associated to the energy eigenvalue of the Schrödinger equation for an electron in an effective confining potential. We numerically solved the Schrödinger equation to evaluate the transmission probability. Our results show that the transmission probability strongly depends on the charging energy stored in the Corbino disk depending on its size.
Determination of phonon decay rate in p-type silicon under Fano resonance by measurement of coherent phonons
Authors: Kato Keiko , Oguri Katsuya , Sanada Haruki , Tawara Takehiko , Sogawa Tetsuomi , Gotoh Hideki
Published: September 2015

We determine phonon decay rate by measuring the temperature dependence of coherent phonons in p-type Si under Fano resonance, where there is interference between the continuum and discrete states. As the temperature decreases, the decay rate of coherent phonons decreases, whereas that evaluated from the Raman linewidth increases. The former follows the anharmonic decay model, whereas the latter does not. The different temperature dependences of the phonon decay rate of the two methods originate from the way that the continuum state, which originates from the Fano resonance, modifies the time- and frequency-domain spectra. The observation of coherent phonons is useful for evaluating the phonon decay rate free from the interaction with the continuum state and clarifies that the anharmonic decay is dominant in p-type Si even under Fano resonance.
Influence of a short-term prepartum supplementation on beef cows and calves’ performance in pastoral conditions
Authors: Quintans G. , Scarsi A. , Roig G. , Carriquiry M. , Banchero G.
Published: September 2015

Multiparous Aberdeen Angus × Hereford crossbred cows were used to evaluate the effect of supplementation during the last month of gestation on milk production and composition and cow and calf performance. Cows were assigned randomly to supplement (SUP; n = 18) or Control (CON; n = 17) treatments. Supplemented cows were offered (1 kg/100 kg bodyweight) a mix of sorghum grain and protein concentrated (67 : 33 as-fed basis; 16% crude protein, 11% acid detergent fibre) from (mean ± s.e.m.) 33 ± 1.4 days prepartum until calving. Before, during, and after the supplementation period, cows grazed together a native pasture paddock with average forage mass available of 1345 kg/ha of dry matter (10.4% crude protein, 45.2% acid detergent fibre). Cows were blood sampled weekly from –42 to 112 days postpartum (DPP) for serum progesterone and non-esterified fatty acids (NEFA) concentrations. Maximum follicle diameter was measured by ovarian ultrasound examination at 60 DPP. The breeding period lasted 60 days and started at 60 ± 1.4 DPP. There was an interaction between treatment and time on BCS (P < 0.0005). Before calving there were no differences in BCS between cows in SUP and in CON, but at calving SUP cows tended (P = 0.10) to present greater BCS and from calving to 84 DPP BCS was greater (P < 0.05) in SUP with respect to CON cows. There was an interaction between treatment and time on plasma NEFA concentrations (P < 0.0005). During the last month of gestation NEFA concentrations were reduced in SUP cows but there were no differences between treatments during the postpartum period. Milk production decreased linearly from 30 to 150 DPP but there was no effect of treatment on it. Calf bodyweight at birth and at weaning did not differ between treatments (37.5 ± 2.4 and 175.6 ± 2.4 kg, respectively). The probability of cows presenting follicles with diameter ≥10 mm was greater (P < 0.05) in SUP than CON cows. The length of the postpartum period did not differ between treatments. The probability of cows cycling during the first 90 DPP and pregnancy rate tended (P = 0.08) to be greater in SUP than in CON cows. Supplementation in winter and for only 30 days in the last month of gestation of beef cows under grazing conditions, increased cows’ BCS without increasing BW of calves, and tended to improve reproductive performance.
Geochemical controls on aluminium concentrations in coastal waters
Authors: Angel Brad M. , Apte Simon C. , Batley Graeme E. , Golding Lisa A.
Published: September 2015

Environmental context Aluminium may be released into coastal waters in dissolved and particulate forms from urban runoff, industrial discharges and acid sulfate soils. Aquatic organisms may experience toxic effects from exposure to dissolved and particulate aluminium. Therefore, the current study reports the geochemical controls such as speciation, precipitation and adsorption that influence the exposure to these aluminium forms in the field and the laboratory. Abstract A combination of field and laboratory investigations was conducted in order to gain an understanding of aluminium dynamics in coastal seawater environments. Filterable (<0.025 and <0.45µm) aluminium concentrations in waters collected from an industrialised coastal location at Gladstone, Central Queensland, Australia ranged from 0.8 to 39.4µgL–1. Size-based separation measurements made on field and laboratory-spiked coastal waters showed colloidal (>0.025 to <0.45µm) aluminium species were generally minimal, apart from one field sample collected close to a river mouth where aluminium was associated with iron-containing colloids. In seawater (pH 8.15, 22°C) spiked with small increments of aluminium so as not to attain supersaturation, the solubility limit was ~500µgL–1. However, at higher total aluminium concentrations the solution chemistry became highly dynamic. In the presence of aluminium precipitate it was not possible to measure a solubility limit over the 28-day duration of the experiment because the dissolved aluminium concentration varied with both reaction time and precipitate concentration. For instance, when seawater solutions were spiked with 10000µgL–1 of total aluminium, a pulse of dissolved aluminium up to 1250µgL–1 was sustained for several days before decreasing to below 100µgL–1 after 28 days. The initial precipitate appeared to be solely aluminium hydroxide and transformed over time to contain increasing magnesium, consistent with the formation of hydrotalcite (Mg6Al2CO3(OH)16·4H2O), reaching 21% of the precipitate mass after 28 days. Adsorption studies showed that at anticipated suspended particulate concentrations for coastal waters, natural particulate material has a fairly low affinity for dissolved aluminium. The results of the current study highlight the complex chemistry of aluminium in marine waters and the role of precipitation reactions.
Strong upslope shifts in Chimborazo's vegetation over two centuries since Humboldt
Authors: Morueta-Holme Naia , Engemann Kristine , Sandoval-Acuña Pablo , Jonas Jeremy D. , Segnitz R. Max , Svenning Jens-Christian
Published: September 2015

Significance

Tropical regions harbor the majority of the world’s biodiversity, but there is debate about whether montane species here are able to track global warming at the same rate as in temperate regions. By following in Humboldt's footsteps and revisiting his pioneering documentation of vegetation elevation ranges, we show that the limit of plant growth has already been strongly pushed upslope. Although the rate of plant range shifts matches that found in other studies, the total magnitude of change in vegetation and glacier coverage on Chimborazo is larger than expected from warming temperatures alone.
The B-cell antigen receptor integrates adaptive and innate immune signals
Authors: Otipoby Kevin L. , Waisman Ari , Derudder Emmanuel , Srinivasan Lakshmi , Franklin Andrew , Rajewsky Klaus
Published: September 2015

Significance

Clonal expansion of antigen-specific B cells during an immune response is necessary for effective antibody production. B cells must integrate signals from their clonally restricted B-cell antigen receptor (BCR) and from nonclonal coreceptors that provide contextual cues to the nature of the antigen. How this is accomplished is unclear. We found that B cells require expression of the BCR for mitogenic responses triggered by coreceptors that recognize innate or T-cell-derived signals. The signaling pathway used by the BCR to license coreceptor-induced proliferation is similar to the previously described BCR-dependent survival signal and, thus, couples B-cell survival and mitogenic responses in an unexpected manner that may have implications for B-cell lymphomagenesis.
Altered BCR and TLR signals promote enhanced positive selection of autoreactive transitional B cells in Wiskott-Aldrich syndrome
Authors: Kolhatkar Nikita S. , Brahmandam Archana , Thouvenel Christopher D. , Becker-Herman Shirly , Jacobs Holly M. , Schwartz Marc A. , Allenspach Eric J. , Khim Socheath , Panigrahi Anil K. , Luning Prak Eline T. , Thrasher Adrian J. , Notarangelo Luigi D. , Candotti Fabio , Torgerson Troy R. , Sanz Ignacio , Rawlings David J.
Published: September 2015

Wiskott-Aldrich syndrome (WAS) is an X-linked immunodeficiency disorder frequently associated with systemic autoimmunity, including autoantibody-mediated cytopenias. WAS protein (WASp)–deficient B cells have increased B cell receptor (BCR) and Toll-like receptor (TLR) signaling, suggesting that these pathways might impact establishment of the mature, naive BCR repertoire. To directly investigate this possibility, we evaluated naive B cell specificity and composition in WASp-deficient mice and WAS subjects (n = 12). High-throughput sequencing and single-cell cloning analysis of the BCR repertoire revealed altered heavy chain usage and enrichment for low-affinity self-reactive specificities in murine marginal zone and human naive B cells. Although negative selection mechanisms including deletion, anergy, and receptor editing were relatively unperturbed, WASp-deficient transitional B cells showed enhanced proliferation in vivo mediated by antigen- and Myd88-dependent signals. Finally, using both BCR sequencing and cell surface analysis with a monoclonal antibody recognizing an intrinsically autoreactive heavy chain, we show enrichment in self-reactive cells specifically at the transitional to naive mature B cell stage in WAS subjects. Our combined data support a model wherein modest alterations in B cell–intrinsic, BCR, and TLR signals in WAS, and likely other autoimmune disorders, are sufficient to alter B cell tolerance via positive selection of self-reactive transitional B cells.
Na,K-ATPase α2 activity in mammalian skeletal muscle T-tubules is acutely stimulated by extracellular K+
Authors: DiFranco Marino , Hakimjavadi Hesamedin , Lingrel Jerry B. , Heiny Judith A.
Published: September 2015

The Na,K-ATPase α2 isoform is the predominant Na,K-ATPase in adult skeletal muscle and the sole Na,K-ATPase in the transverse tubules (T-tubules). In quiescent muscles, the α2 isozyme operates substantially below its maximal transport capacity. Unlike the α1 isoform, the α2 isoform is not required for maintaining resting ion gradients or the resting membrane potential, canonical roles of the Na,K-ATPase in most other cells. However, α2 activity is stimulated immediately upon the start of contraction and, in working muscles, its contribution is crucial to maintaining excitation and resisting fatigue. Here, we show that α2 activity is determined in part by the K+ concentration in the T-tubules, through its K+ substrate affinity. Apparent K+ affinity was determined from measurements of the K1/2 for K+ activation of pump current in intact, voltage-clamped mouse flexor digitorum brevis muscle fibers. Pump current generated by the α2 Na,K-ATPase, Ip, was identified as the outward current activated by K+ and inhibited by micromolar ouabain. Ip was outward at all potentials studied (−90 to −30 mV) and increased with depolarization in the subthreshold range, −90 to −50 mV. The Q10 was 2.1 over the range of 22–37°C. The K1/2,K of Ip was 4.3 ± 0.3 mM at −90 mV and was relatively voltage independent. This K+ affinity is lower than that reported for other cell types but closely matches the dynamic range of extracellular K+ concentrations in the T-tubules. During muscle contraction, T-tubule luminal K+ increases in proportion to the frequency and duration of action potential firing. This K1/2,K predicts a low fractional occupancy of K+ substrate sites at the resting extracellular K+ concentration, with occupancy increasing in proportion to the frequency of membrane excitation. The stimulation of preexisting pumps by greater K+ site occupancy thus provides a rapid mechanism for increasing α2 activity in working muscles.
A lower bound and estimate of the lowest eigenvalue of a second order Floquet equation
Authors: Kriegsmann G.
Published: September 2015

A bound on the lowest eigenvalue of a second order Floquet problem is derived by applying the Cauchy Integral Theorem. Specifically, we chose a special function which depends on an arbitrary positive parameter

S
≥
1

S\ge 1

. We use the residue theorem and show that its residue at the origin determines an infinite sum composed of reciprocals of the eigenvalues raised to the

2
S

2S

power. A simple bound gives us our result. We show that the residue depends explicitly on the power series expansions, in the eigen-parameter, of the original equation’s fundamental solutions. The coefficients of these power series are computed recursively.

Three typical examples are presented, and it is shown for these cases that the lower bound, derived in this paper, actually affords a good approximation to the first eigenvalue. We show this for the case only of

S
=
1

S=1

.
PyPDB: a Python API for the Protein Data Bank
Authors: Gilpin William
Published: September 2015

Summary: We have created a Python programming interface for the RCSB Protein Data Bank (PDB) that allows search and data retrieval for a wide range of result types, including BLAST and sequence motif queries. The API relies on the existing XML-based API and operates by creating custom XML requests from native Python types, allowing extensibility and straightforward modification. The package has the ability to perform many types of advanced search of the PDB that are otherwise only available through the PDB website.

Availability and implementation: PyPDB is implemented exclusively in Python 3 using standard libraries for maximal compatibility. The most up-to-date version, including iPython notebooks containing usage tutorials, is available free-of-charge under an open-source MIT license via GitHub at https://github.com/williamgilpin/pypdb, and the full API reference is at http://williamgilpin.github.io/pypdb_docs/html/. The latest stable release is also available on PyPI.

Contact:  wgilpin@stanford.edu
Clinicopathologic Characteristics of Microsatellite Instable Gastric Carcinomas Revisited: Urgent Need for Standardization
Authors: Mathiak Micaela , Warneke Viktoria S. , Behrens Hans-Michael , Haag Jochen , Böger Christine , Krüger Sandra , Röcken Christoph
Published: September 2015

Microsatellite instable gastric cancer (MSI-GC) is a specific molecular subtype of GC. We studied the phenotypes, genotypes, and clinicopathologic characteristics of MSI-GC in a white GC cohort and compared our findings with an extended literature review. The study cohort consisted of 482 patients. Specimens were available from 452 cases and were used for immunostaining (MLH1, PMS2, MSH2, MSH6) and molecular biological analyses (BAT-25, BAT-26, NR-21, NR-24, NR-27; Epstein-Barr virus in situ hybridization). Thirty-four (7.5%) GCs were MSI. Loss of MLH1 and/or PMS2 was found in 30 (88%) MSI-GC, 3 (9%) showed loss of MSH2 and/or MSH6. One (3%) MSI-GC was identified only by molecular biological testing. A single case was heterogeneous and contained microsatellite-stable and instable tumor areas. Twenty-one (62%) MSI-GCs showed unusual histologic features. MSI-GC was not found in diffuse-type or Epstein-Barr virus-positive GC. MSI-GC was significantly more prevalent in elderly patients, distal stomach, and was associated with a significantly lower number of lymph node metastases and a significantly better overall and tumor-specific survival. MSI-GC constitutes a small but relevant subgroup of GC with distinct clinicopathologic characteristics. Our literature review illustrates the shortcomings of missing standardized testing algorithms with prevalences of MSI-GC ranging from 0% to 44.5%. Future studies should test the hypothesis that patients with MSI-GCs may not need adjuvant/perioperative chemotherapy. However, this will require a standardized, quality-controlled diagnostic algorithm of MSI for GC.
Roseovarius aquimarinus sp. nov., a slightly halophilic bacterium isolated from seawater
Authors: Kang Hyeonji , Kim Jong-Hwa , Jeon Che Ok , Yoon Jung-Hoon , Kim Wonyong
Published: September 2015

A Gram-stain-negative, non-spore-forming, rod-shaped, motile, facultatively anaerobic bacterium, designated CAU 1059T, was isolated from a seawater sample from Jeju Island, Republic of Korea. The bacterium grew optimally at 37 °C, at pH 7.0 and in the presence of 2 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CAU 1059T belonged to the genus Roseovarius. It exhibited only 91.5–96.9 % sequence similarity to the type strains of recognized Roseovarius species. Similar to other species of the genus Roseovarius, strain CAU 1059T had ubiquinone-10 (Q-10) as the predominant ubiquinone and C16 : 0 and summed feature 8 (C18 : 1ω7c/ω6c) as the major fatty acids. The polar lipid pattern consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine; three unidentified phospholipids, two aminolipids, an aminophospholipid and nine other lipids were also found. The G+C content of the genomic DNA was 61.9 mol%. On the basis of the data provided, strain CAU 1059T should be classified as representing a novel species of the genus Roseovarius, for which the name Roseovarius aquimarinus sp. nov. is proposed. The type strain is CAU 1059T ( = KCTC 32014T = CCUG 64792T).
Rhodanobacter aciditrophus sp. nov., an acidophilic bacterium isolated from mine wastewater
Authors: Koh Hyeon-Woo , Hong Heeji , Min Ui-Gi , Kang Myung-Suk , Kim Song-Gun , Na Jeong-Geol , Rhee Sung-Keun , Park Soo-Je
Published: September 2015

A novel strain (designated sjH1T), characterized as aerobic, Gram-stain-negative, oxidase-positive, catalase-negative, motile and rod-shaped, was isolated from mine wastewater. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain sjH1T belonged to the genus Rhodanobacter. Strain sjH1T was closely related to Rhodanobacter thiooxydans LCS2T (98.0% 16S rRNA gene sequence similarity), Rhodanobacter denitrificans 2APBS1T (97.7%), Rhodanobacter soli DCY45T (97.2%) and Rhodanobacter caeni MJ01T (97.0%). The DNA G+C content of strain sjH1T was 69.2 mol%. DNA–DNA relatedness ( < 60%) indicated that strain sjH1T represents a distinct species that is separate from R. thiooxydans, R. denitrificans, R. soli and R. caeni. The major ubiquinone was Q-8, and major fatty acids were summed feature 9 (iso–C17 : 1ω9c and/or C16 : 0 10-methyl), iso-C15 : 0, iso-C17 : 0, iso-C16 : 0 and anteiso-C15 : 0. Based on data from this polyphasic study, it is proposed that sjH1T ( = KCTC 42660T = JCM 30774T) is the type strain of a novel species, Rhodanobacter aciditrophus sp. nov.
Evaluating the role of phage-shock protein A in Burkholderia pseudomallei
Authors: Southern Stephanie J. , Male Abigail , Milne Timothy , Sarkar-Tyson Mitali , Tavassoli Ali , Oyston Petra C. F.
Published: September 2015

The phage-shock protein (Psp) response is an extracytoplasmic response system that is vital for maintenance of the cytoplasmic membrane when the cell encounters stressful conditions. The paradigm of the Psp response has been established in Escherichia coli. The response has been shown to be important for survival during the stationary phase, maintenance of the proton motive force across membranes and implicated in virulence. In this study, we identified a putative PspA homologue in Burkholderia pseudomallei, annotated as BPSL2105. Similar to the induction of PspA in E. coli, the expression of B. pseudomallei BPSL2105 was induced by heat shock. Deletion of BPSL2105 resulted in a survival defect in the late stationary phase coincident with dramatic changes in the pH of the culture medium. The B. pseudomallei BPSL2105 deletion mutant also displayed reduced survival in macrophage infection – the first indication that the Psp response plays a role during intracellular pathogenesis in this species. The purified protein formed large oligomeric structures similar to those observed for the PspA protein of E. coli, and PspA homologues in Bacillus, cyanobacteria and higher plants, providing further evidence to support the identification of BPSL2105 as a PspA-like protein in B. pseudomallei.
The rise and fall of stand-alone social reporting in a multinational subsidiary in Bangladesh
Authors: Belal Ataur , Owen David L
Published: September 2015

Purpose

– The purpose of this paper is to examine the underlying drivers for the development and subsequent discontinuation of stand-alone corporate social responsibility (CSR) reporting in a multinational subsidiary in Bangladesh.

Design/methodology/approach

– The research approach employed for this purpose is a case study using evidence from a series of in-depth interviews conducted during the period 2002-2010. Interview data are supplemented by examining other sources of information including annual reports, stand-alone social reports and relevant newspaper articles during the study period.

Findings

– It appears that the stand-alone CSR reporting process was initiated to give the subsidiary a formal space in which to legitimise its activities in Bangladesh where both tobacco control regulation and a strong anti-tobacco movement were gaining momentum. At the start of the process in 2002 corporate interviewees were very receptive of this initiative and strongly believed that it would not be a one off exercise. However, in the face of subsequent significant national policy shifts concerning tobacco control, irreconcilable stakeholder demands and increasing criticism of the CSR activities of the organisation at home and abroad the process was brought to an abrupt end in 2009.

Research limitations/implications

– The paper has a number of implications for policy makers concerning the future prospects for stand-alone social/sustainability reporting as a means of enhancing organisational transparency and accountability. In addition the paper discusses a number of theoretical implications for the development of legitimacy theory.

Originality/value

– Using the lens of legitimacy the paper theorises the circumstances leading to the initiation and subsequent cessation of CSR reporting in the organisation concerned. As far as the authors know this is the first study which theorises and provides significant fieldwork-based empirical evidence regarding the discontinuation of stand-alone social reporting by a multinational company operating in a developing country. Thus, it extends previous desk-based attempts at using legitimacy theory to explain a decrease (or discontinuity) in CSR disclosures by de Villiers and van Staden (2006) and Tilling and Tilt (2010).
Does stakeholder pressure influence corporate GHG emissions reporting? Empirical evidence from Europe
Authors: Liesen Andrea , Hoepner Andreas G. , Patten Dennis M. , Figge Frank
Published: September 2015

Purpose

– The purpose of this paper is to seek to shed light on the practice of incomplete corporate disclosure of quantitative Greenhouse gas (GHG) emissions and investigates whether external stakeholder pressure influences the existence, and separately, the completeness of voluntary GHG emissions disclosures by 431 European companies.

Design/methodology/approach

– A classification of reporting completeness is developed with respect to the scope, type and reporting boundary of GHG emissions based on the guidelines of the GHG Protocol, Global Reporting Initiative and the Carbon Disclosure Project. Logistic regression analysis is applied to examine whether proxies for exposure to climate change concerns from different stakeholder groups influence the existence and/or completeness of quantitative GHG emissions disclosure.

Findings

– From 2005 to 2009, on average only 15 percent of companies that disclose GHG emissions report them in a manner that the authors consider complete. Results of regression analyses suggest that external stakeholder pressure is a determinant of the existence but not the completeness of emissions disclosure. Findings are consistent with stakeholder theory arguments that companies respond to external stakeholder pressure to report GHG emissions, but also with legitimacy theory claims that firms can use carbon disclosure, in this case the incomplete reporting of emissions, as a symbolic act to address legitimacy exposures.

Practical implications

– Bringing corporate GHG emissions disclosure in line with recommended guidelines will require either more direct stakeholder pressure or, perhaps, a mandated disclosure regime. In the meantime, users of the data will need to carefully consider the relevance of the reported data and develop the necessary competencies to detect and control for its incompleteness. A more troubling concern is that stakeholders may instead grow to accept less than complete disclosure.

Originality/value

– The paper represents the first large-scale empirical study into the completeness of companies’ disclosure of quantitative GHG emissions and is the first to analyze these disclosures in the context of stakeholder pressure and its relation to legitimation.
Differences in organizational web site design across cultures
Authors: Wang Valerie , Lou Hao , Wang Yong , Guo Chiquan
Published: September 2015

Purpose

– The purpose of this paper is to compare organizational web site design attributes between US and Chinese small- and medium-sized enterprises (SMEs).

Design/methodology/approach

– The study uses 18 web site design variables identified by previous research.

Findings

– The results show that US and Chinese SME corporate web sites have both similarities and differences in terms of web site design attributes. The design differences are not much affected by the impacts of macro-economy and technology gaps. However, US and Chinese SMEs may differ in terms of their marketing practices and cultural orientations, and as a result, web site design attributes still remain significantly different.

Originality/value

– Marketing and cultural factors are found to be important determinants in SMEs’ organizational web site design across the two countries.
Benefits, criteria and activities of supplier development: a categorical literature review
Authors: Dalvi Manojkumar Vithalrao , Kant Ravi
Published: September 2015

Purpose

– Supplier development (SD) is a kind of collaboration among a buyer and a supplier to seek constant improvement in supplier performance and capabilities to provide better quality, on-time delivery of products and services at lower cost. The purpose of this paper is to exhibit and summarize the important aspects of SD benefits, SD criteria and SD activities.

Design/methodology/approach

– The review of SD aspects is based on 72 papers published from 1991 to till date in academic databases namely Science Direct, Emerald, Springer-Link Journals and IEEE Xplore with “supplier development” and “vendor development” as keywords.

Findings

– Through the literature review, this paper brings up the analysis of aforementioned aspect of SD in detail and put forth 43 SD benefits, 23 SD criteria and 9 SD activities. This paper also presents the important SD benefits, SD criteria and SD activities based on the occurrence in literature.

Research limitations/implications

– The literature on practical difficulties for implementation of SD activities, and trade-off between benefits and risk associated with SD activities are seldom available.

Originality/value

– This paper presents a literature review on three crucial aspects namely SD benefits, SD criteria and SD activities. The SD benefits, SD criteria and SD activities are identified according to their level of importance. The main contribution of this paper is to draw together three above mentioned important aspects of SD.
Measuring attitudes toward plagiarism: issues and psychometric solutions
Authors: Ehrich John , Howard Steven , Tognolini James , Bokosmaty Sahar
Published: September 2015

Purpose

– The purpose of this paper is to address the issue of failing to psychometrically test questionnaire instruments when measuring university students’ attitudes towards plagiarism. These issues are highlighted by a psychometric evaluation of a commonly used (but previously untested) plagiarism attitudinal scale.

Design/methodology/approach

– The importance of psychometric testing is shown through an analysis of a commonly used scale using modern techniques (e.g. Rasch analysis) on 131 undergraduate education students at an Australian university.

Findings

– Psychometric analysis revealed the scale to be unreliable in its present form. However, when reduced to an eight-item subscale it became marginally reliable.

Research limitations/implications

– The main implication of this paper is that questionnaire instruments cannot be assumed to function as they are intended without thorough psychometric testing.

Practical implications

– The paper offers valuable insight into the psychometric properties of a previously untested but commonly used plagiarism attitudinal scale.

Originality/value

– The paper offers a straightforward and easy to understand introduction to researchers in higher education who use questionnaires/surveys in their research but lack an understanding of why psychometric testing is so critical. While similar papers have been written in other fields which advocate psychometric approaches, such as Rasch analysis, this has not been the case in higher educational research (or mainstream educational research for that matter).
The use of eportfolios as a pedagogical tool for leadership preparation and development in education
Authors: Giles David , Bell Michael
Published: September 2015

Purpose

– A critical function of leadership formation is the leader’s deepening sensitivity, reflexivity, and self-reflection on one’s own, and others, practice. A particular tool that has potential to support such endeavour is the eportfolio (EP) (currently referred to as a personal learning space). The paper aims to discuss these issues.

Design/methodology/approach

– The paper presents a personal report from a collaborative self-study which focused on the usefulness and potential of EPs as a tool for leadership formation that might: first, support learning enquiries, second, enable contemplative thinking and reflection, and third, coordinate personal representations of “who” we are.

Findings

– Having engaged as academics in a collaborative quest to embrace the technology of EPs in the everyday professional lives, while also critiquing the influence and power of the tool, the authors present a personal position for the use of EPs in leadership programmes as well as some critical dimensions that appear to awaken and enable self-reflective practices.

Originality/value

– As a tool which can enable leadership formation, EPs can evoke individual and collective voice within a generative and shared space.
Crowding at the frontier: boundary spanners, gatekeepers and knowledge brokers
Authors: Haas Aurore
Published: September 2015

Purpose

– This paper aims to contribute to defining the concepts of boundary spanner, gatekeeper and knowledge broker.

Design/methodology/approach

– A review of the literature covering more than 100 sources.

Findings

– A review of past research leads to proposing a set of new definitions and also to the detection of six research avenues.

Originality/value

– The ability of organizations to recognize, source and integrate key information or knowledge is important for their strategy, innovation and performance over time. Three types of individuals have information gathering and knowledge dissemination roles at the frontier of organizations and groups: boundary spanners, gatekeepers and knowledge brokers. Although research on these individuals is well-developed, we found that in practice, the definitions of the concepts overlap and still need a clarification. So far, no systematic comparison of these roles has been undertaken.