bluuebunny/crossref_metadata_2025 huggingface dataset:
Ionic liquids behave as dilute electrolyte solutions
Authors: Gebbie Matthew A. , Valtiner Markus , Banquy Xavier , Fox Eric T. , Henderson Wesley A. , Israelachvili Jacob N.
Published: May 2013

We combine direct surface force measurements with thermodynamic arguments to demonstrate that pure ionic liquids are expected to behave as dilute weak electrolyte solutions, with typical effective dissociated ion concentrations of less than 0.1% at room temperature. We performed equilibrium force–distance measurements across the common ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C4mim][NTf2]) using a surface forces apparatus with in situ electrochemical control and quantitatively modeled these measurements using the van der Waals and electrostatic double-layer forces of the Derjaguin–Landau–Verwey–Overbeek theory with an additive repulsive steric (entropic) ion–surface binding force. Our results indicate that ionic liquids screen charged surfaces through the formation of both bound (Stern) and diffuse electric double layers, where the diffuse double layer is comprised of effectively dissociated ionic liquid ions. Additionally, we used the energetics of thermally dissociating ions in a dielectric medium to quantitatively predict the equilibrium for the effective dissociation reaction of [C4mim][NTf2] ions, in excellent agreement with the measured Debye length. Our results clearly demonstrate that, outside of the bound double layer, most of the ions in [C4mim][NTf2] are not effectively dissociated and thus do not contribute to electrostatic screening. We also provide a general, molecular-scale framework for designing ionic liquids with significantly increased dissociated charge densities via judiciously balancing ion pair interactions with bulk dielectric properties. Our results clear up several inconsistencies that have hampered scientific progress in this important area and guide the rational design of unique, high–free-ion density ionic liquids and ionic liquid blends.
Tension modulates actin filament polymerization mediated by formin and profilin
Authors: Courtemanche Naomi , Lee Ja Yil , Pollard Thomas D. , Greene Eric C.
Published: May 2013

Formins promote processive elongation of actin filaments for cytokinetic contractile rings and other cellular structures. In vivo, these structures are exposed to tension, but the effect of tension on these processes was unknown. Here we used single-molecule imaging to investigate the effects of tension on actin polymerization mediated by yeast formin Bni1p. Small forces on the filaments dramatically slowed formin-mediated polymerization in the absence of profilin, but resulted in faster polymerization in the presence of profilin. We propose that force shifts the conformational equilibrium of the end of a filament associated with formin homology 2 domains toward the closed state that precludes polymerization, but that profilin–actin associated with formin homology 1 domains reverses this effect. Thus, physical forces strongly influence actin assembly by formin Bni1p.
Asymptotic stability of the wave equation on compact manifolds and locally distributed viscoelastic dissipation
Authors: Cavalcanti Marcelo , Domingos Cavalcanti Valéria , F. Nascimento Flávio
Published: May 2013

We discuss the asymptotic stability of the wave equation on a compact Riemannian manifold

(
M
,
g
)

(M, \bf g)

subject to locally distributed viscoelastic effects on a subset

ω
⊂
M

\omega \subset M

. Assuming that the well-known geometric control condition

(
ω
,

T
0

)

(\omega , T_0)

holds and supposing that the relaxation function is bounded by a function that decays exponentially to zero, we show that the solutions of the corresponding partial viscoelastic model decay exponentially to zero. We give a new geometric proof extending the prior results in the literature from the Euclidean setting to compact Riemannian manifolds (with or without boundary).
HitPick: a web server for hit identification and target prediction of chemical screenings
Authors: Liu Xueping , Vogt Ingo , Haque Tanzeem , Campillos Mónica
Published: May 2013

Motivation: High-throughput phenotypic assays reveal information about the molecules that modulate biological processes, such as a disease phenotype and a signaling pathway. In these assays, the identification of hits along with their molecular targets is critical to understand the chemical activities modulating the biological system. Here, we present HitPick, a web server for identification of hits in high-throughput chemical screenings and prediction of their molecular targets. HitPick applies the B-score method for hit identification and a newly developed approach combining 1-nearest-neighbor (1NN) similarity searching and Laplacian-modified naïve Bayesian target models to predict targets of identified hits. The performance of the HitPick web server is presented and discussed.

Availability: The server can be accessed at http://mips.helmholtz-muenchen.de/proj/hitpick.

Contact:  monica.campillos@helmholtz-muenchen.de
EpiCombFlu: exploring known influenza epitopes and their combination to design a universal influenza vaccine
Authors: Jaiswal Varun , Chanumolu Sree K. , Sharma Pankaj , Chauhan Rajinder S. , Rout Chittaranjan
Published: May 2013

Motivation: Influenza is responsible for half a million deaths annually, and vaccination is the best preventive measure against this pervasive health problem. Influenza vaccines developed from surveillance data of each season are strain-specific, and therefore, are unable to provide protection against pandemic strains arising from antigenic shift and drift. Seasonal epidemics and occasional pandemics of influenza have created a need for a universal influenza vaccine (UIV). Researchers have shown that a combination of conserved epitopes has the potential to be used as a UIV.

Result: In the present work, available data on strains, proteins, epitopes and their associated information were used to develop a Web resource, ‘EpiCombFlu’, which can explore different influenza epitopes and their combinations for conservation among different strains, population coverage and immune response for vaccine design. Forward selection algorithm was implemented in EpiCombFlu to select optimum combination of epitopes that may be expressed and evaluated as potential UIV.

Availability: The Web resource is freely available at http://117.211.115.67/influenza/home.html.

Contact:  chittaranjan.rout@juit.ac.in

Supplementary information:  Supplementary data are available at Bioinformatics online.
Tomato Below Ground–Above Ground Interactions: Trichoderma longibrachiatum Affects the Performance of Macrosiphum euphorbiae and Its Natural Antagonists
Authors: Battaglia Donatella , Bossi Simone , Cascone Pasquale , Digilio Maria Cristina , Prieto Juliana Duran , Fanti Paolo , Guerrieri Emilio , Iodice Luigi , Lingua Guido , Lorito Matteo , Maffei Massimo E. , Massa Nadia , Ruocco Michelina , Sasso Raffaele , Trotta Vincenzo
Published: May 2013

Below ground and above ground plant–insect–microorganism interactions are complex and regulate most of the developmental responses of important crop plants such as tomato. We investigated the influence of root colonization by a nonmycorrhizal plant-growth-promoting fungus on direct and indirect defenses of tomato plant against aphids. The multitrophic system included the plant Solanum lycopersicum (‘San Marzano nano’), the root-associated biocontrol fungus Trichoderma longibrachiatum strain MK1, the aphid Macrosiphum euphorbiae (a tomato pest), the aphid parasitoid Aphidius ervi, and the aphid predator Macrolophus pygmaeus. Laboratory bioassays were performed to assess the effect of T. longibrachiatum MK1, interacting with the tomato plant, on quantity and quality of volatile organic compounds (VOC) released by tomato plant, aphid development and reproduction, parasitoid behavior, and predator behavior and development. When compared with the uncolonized controls, plants whose roots were colonized by T. longibrachiatum MK1 showed quantitative differences in the release of specific VOC, better aphid population growth indices, a higher attractiveness toward the aphid parasitoid and the aphid predator, and a quicker development of aphid predator. These findings support the development of novel strategies of integrated control of aphid pests. The species-specific or strain-specific characteristics of these below ground–above ground interactions remain to be assessed.
The Rice Bacterial Pathogen Xanthomonas oryzae pv. oryzae Produces 3-Hydroxybenzoic Acid and 4-Hydroxybenzoic Acid via XanB2 for Use in Xanthomonadin, Ubiquinone, and Exopolysaccharide Biosynthesis
Authors: Zhou Lian , Huang Tin-Wei , Wang Jia-Yuan , Sun Shuang , Chen Gongyou , Poplawsky Alan , He Ya-Wen
Published: May 2013

Xanthomonas oryzae pv. oryzae, the causal agent of rice bacterial blight, produces membrane-bound yellow pigments, referred to as xanthomonadins. Xanthomonadins protect the pathogen from photodamage and host-induced perioxidation damage. They are also required for epiphytic survival and successful host plant infection. Here, we show that XanB2 encoded by PXO_3739 plays a key role in xanthomonadin and coenzyme Q8 biosynthesis in X. oryzae pv. oryzae PXO99A. A xanB2 deletion mutant exhibits a pleiotropic phenotype, including xanthomonadin deficiency, producing less exopolysaccharide (EPS), lower viability and H2O2 resistance, and lower virulence. We further demonstrate that X. oryzae pv. oryzae produces 3-hydroxybenzoic acid (3-HBA) and 4-hydroxybenzoic acid (4-HBA) via XanB2. 3-HBA is associated with xanthomonadin biosynthesis while 4-HBA is mainly used as a precursor for coenzyme Q (CoQ)8 biosynthesis. XanB2 is the alternative source of 4-HBA for CoQ8 biosynthesis in PXO99A. These findings suggest that the roles of XanB2 in PXO99A are generally consistent with those in X. campestris pv. campestris. The present study also demonstrated that X. oryzae pv. oryzae PXO99A has evolved several specific features in 3-HBA and 4-HBA signaling. First, our results showed that PXO99A produces less 3-HBA and 4-HBA than X. campestris pv. campestris and this is partially due to a degenerated 4-HBA efflux pump. Second, PXO99A has evolved unique xanthomonadin induction patterns via 3-HBA and 4-HBA. Third, our results showed that 3-HBA or 4-HBA positively regulates the expression of gum cluster to promote EPS production in PXO99A. Taken together, the results of this study indicate that XanB2 is a key metabolic enzyme linking xanthomonadin, CoQ, and EPS biosynthesis, which are collectively essential for X. oryzae pv. oryzae pathogenesis.
Occurrence of Meloidogyne fallax in North America, and Molecular Characterization of M. fallax and M. minor from U.S. Golf Course Greens
Authors: Nischwitz Claudia , Skantar Andrea , Handoo Zafar A. , Hult Maria N. , Schmitt Mark E. , McClure Michael A.
Published: May 2013

Several species of root-knot nematodes (Meloidogyne spp.) are known to have significant presence on turfgrass in golf course greens, particularly in the western United States. Nematodes isolated from a golf course in King County, WA were identified as Meloidogyne minor based on analysis of the large ribosomal subunit (LSU 28S D2-D3 expansion segment), the internal transcribed spacers 1 and 2 (ITS rDNA), the intergenic spacer region 2 (IGS2), and the nuclear protein-coding gene Hsp90. Sequence-characterized amplified region (SCAR) primers that were originally designed to be specific for M. fallax were found to cross-react with M. minor. A population from California was determined to be M. fallax based on juvenile tail morphology and analysis of the ribosomal markers and Hsp90, comprising the first report of this species in North America. Using trees based on Hsp90 genomic alignments, the phylogenetic relationships of these populations and known root-knot nematode species were congruent with previous trees based on ribosomal genes. Resolution of M. fallax and M. chitwoodi using Hsp90 was equivalent to species separation obtained with 28S or 18S rDNA alignments. The strengths and weaknesses of ribosomal and Hsp90 markers, and the use of SCAR polymerase chain reaction as diagnostic tools are discussed.
First Report of “Candidatus Liberibacter solanacearum” on Tomato in Honduras
Authors: Aguilar E. , Sengoda V. G. , Bextine B. , McCue K. F. , Munyaneza J. E.
Published: May 2013

Tomato (Lycopersicum esculentum) crops grown in several departments of Honduras and heavily infested with the psyllid Bactericera cockerelli were observed in April of 2012 with plant symptoms suggestive of “Candidatus Liberibacter solanacearum” infection. B. cockerelli is a serious pest of potato, tomato, and other solanaceous plants and a vector of “Ca. L. solanacearum” (1,2,3,4). The symptoms included overall chlorosis, severe stunting, leaf cupping, excessive branching of axillary shoots, and leaf purpling and scorching (2,3). Disease incidence ranged from 5 to 50% symptomatic plants per field. Tomato (cv. Pony) plant samples were collected from two psyllid-infested commercial fields in the municipalities of Danli and Comayagua in the departments of El-Paraiso and Comayagua, respectively. Total DNA was extracted from leaf tissues of 50 and 20 symptomatic and asymptomatic plants, respectively, with the cetyltrimethylammonium bromide (CTAB) buffer extraction method (1,3). The DNA samples were tested for “Ca. L. solanacearum” by PCR with primer pairs specific for 16S rDNA (OA2 and OI2c) and the outer membrane protein gene (OMB 1482f and 2086r) of the bacterium (1,2). Ten (20%) of the 50 symptomatic tomato samples were positive for “Ca. L. solanacearum” using both primer pairs and the remaining samples were negative for the bacterium with both primer sets. None of the 20 asymptomatic plants tested positive for “Ca. L. solanacearum”. Amplicons from DNA of two plant samples (one plant/municipality) with each primer pair were cloned and four clones of each of the four amplicons were sequenced. BLASTn analysis of the 16S rDNA consensus sequences from the clones (deposited in GenBank as Accession Nos. KC768321 and KC768322) were identical for both locations and showed 99 to 100% identity to several “Ca. L. solanacearum” sequences in GenBank (e.g., JN848753, JN84856, and HM246509). The OMB consensus sequences from the two tomato plants (deposited in GenBank as KC768329 and KC768330) were 100% identical to OMB sequences of Lso in GenBank (CP002371 and JN48754, respectively). To our knowledge, this is the first report of “Ca. Liberibacter solanacearum” associated with tomato crops in Honduras. This bacterium has caused millions of dollars in losses to the tomato industry in the United States, Mexico, and New Zealand (2,3,4). Serious damages to tomato crops due to “Ca. L. solanacearum” could expand throughout Central America, especially in those countries where B. cockerelli occurs.

References: (1) J. M. Crosslin. Southwest. Entomol. 36:125, 2011. (2) L. W. Liefting et al. Plant Dis. 93:208, 2009. (3) J. E. Munyaneza et al. Plant Dis. 93:1076, 2009. (4) J. E. Munyaneza. Am. J. Pot. Res. 89:329, 2012.
Phomopsis Dieback: A Grapevine Trunk Disease Caused byPhomopsis viticolain California
Authors: Úrbez-Torres J. R. , Peduto F. , Smith R. J. , Gubler W. D.
Published: May 2013

Field surveys recently conducted in California and in other grape-growing regions in the United States showed Phomopsis viticola to be one of the most prevalent fungi isolated from grapevine perennial cankers in declining vines. The current study has not only confirmed the presence of P. viticola from grapevine cankers in California but also has for the first time revealed the occurrence of Diaporthe ambigua, D. eres, and D. neotheicola in symptomatic grapevine wood in California by means of morphological studies and multi-gene sequence analysis. Pathogenicity trials conducted on mature cordons of Vitis vinifera ‘Syrah’ and ‘Red Globe’, as well as on lignified Syrah dormant canes, showed P. viticola isolates from California to be capable of causing perennial cankers. Lengths of vascular discoloration caused by P. viticola were similar to those caused by Eutypa lata and several Botryosphaeriaceae spp., which are well-known grapevine trunk disease pathogens. Additionally, a lack of spring growth was commonly observed in dormant canes inoculated with P. viticola spore suspensions in two pathogenicity trials. As part of this study, V. vinifera ‘Cabernet Sauvignon’ and ‘Zinfandel’ wood was shown to be more susceptible to infection by P. viticola than ‘Barbera’, ‘Chardonnay’, ‘Merlot’, and ‘Thompson Seedless’ wood. After more than 40 years overlooking P. viticola as a grapevine wood pathogen, this study provides strong evidence of the role of P. viticola as a canker-causing organism, and suggests its addition to the fungi involved in the grapevine trunk disease complex. Results from this study suggest D. ambigua and D. neotheicola to be saprophytes or weak pathogens on grapevine wood.
Age-related effects on malaria parasite infection in wild chimpanzees
Authors: De Nys Hélène M. , Calvignac-Spencer Sébastien , Thiesen Ursula , Boesch Christophe , Wittig Roman M. , Mundry Roger , Leendertz Fabian H.
Published: May 2013

Wild great apes are widely infected with a number of malaria parasites (
Plasmodium
spp.). Yet, nothing is known about the biology of these infections in the wild. Using faecal samples collected from wild chimpanzees, we investigated the effect of age on
Plasmodium
spp. detection rates. The data show a strong association between age and malaria parasite positivity, with significantly lower detection rates in adults. This suggests that, as in humans, individuals reaching adulthood have mounted an effective protective immunity against malaria parasites.
Canadian fishery closures provide a large-scale test of the impact of gillnet bycatch on seabird populations
Authors: Regular Paul , Montevecchi William , Hedd April , Robertson Gregory , Wilhelm Sabina
Published: May 2013

In 1992, the eastern Canadian gillnet fisheries for northern cod and Atlantic salmon were largely closed. These large-scale fishery closures resulted in the removal of tens of thousands of gillnets known to inflict high levels of seabird mortality. We used this unprecedented opportunity to test the effects of gillnet removal on seabird populations. Consistent with predictions, we show that the breeding populations of divers (auks, gannets; susceptible to gillnet bycatch) have increased from pre-closure levels, whereas the populations of scavenging surface-feeders (gulls; low vulnerability to gillnet bycatch but susceptible to removal of fisheries discards) have decreased. Using the most complete series of seabird census data for the species most vulnerable to bycatch, we demonstrate a positive population response of common murres to reduction in gillnet fishing within its foraging range. These findings support the widespread but seldom documented contention that fisheries bycatch negatively impacts populations of non-target large vertebrates.
Experimental evolution reveals trade-offs between mating and immunity
Authors: McNamara Kathryn B. , Wedell Nina , Simmons Leigh W.
Published: May 2013

Immune system maintenance and upregulation is costly. Sexual selection intensity, which increases male investment into reproductive traits, is expected to create trade-offs with immune function. We assayed phenoloxidase (PO) and lytic activity of individuals from populations of the Indian meal moth,
Plodia interpunctella
, which had been evolving under different intensities of sexual selection. We found significant divergence among populations, with males from female-biased populations having lower PO activity than males from balanced sex ratio or male-biased populations. There was no divergence in anti-bacterial lytic activity. Our data suggest that it is the increased male mating demands in female-biased populations that trades-off against immunity, and not the increased investment in sperm transfer per mating that characterizes male-biased populations.
To breed or not to breed: endocrine response to mercury contamination by an Arctic seabird
Authors: Tartu Sabrina , Goutte Aurélie , Bustamante Paco , Angelier Frédéric , Moe Børge , Clément-Chastel Céline , Bech Claus , Gabrielsen Geir Wing , Bustnes Jan Ove , Chastel Olivier
Published: May 2013

Mercury, a ubiquitous toxic element, is known to alter expression of sex steroids and to impair reproduction across vertebrates but the mechanisms underlying these effects are not clearly identified. We examined whether contamination by mercury predicts the probability to skip reproduction in black-legged kittiwakes (
Rissa tridactyla
) from Svalbard. We also manipulated the endocrine system to investigate the mechanism underlying this relationship. During the pre-laying period, we injected exogenous GnRH (gonadotropin-releasing hormone) to test the ability of the pituitary to release luteinizing hormone (LH, a key hormone for the release of sex steroids and hence breeding) in relation to mercury burden. Birds that skipped reproduction had significantly higher mercury concentration in blood than breeders. Endocrine profiles of these birds also varied based on breeding status (breeders versus non-breeders), mercury contamination and sex. Specifically, in skippers (birds that did not breed), baseline LH decreased with increasing mercury concentration in males, whereas it increased in females. GnRH-induced LH levels increased with increasing mercury concentration in both sexes. These results suggest that mercury contamination may disrupt GnRH input to the pituitary. Thus, high mercury concentration could affect the ability of long-lived birds to modulate their reproductive effort (skipping or breeding) according to ongoing environmental changes in the Arctic, thereby impacting population dynamics.
Ribosome flow model with positive feedback
Authors: Margaliot Michael , Tuller Tamir
Published: May 2013

Eukaryotic mRNAs usually form a circular structure; thus, ribosomes that terminatae translation at the 3′ end can diffuse with increased probability to the 5′ end of the transcript, initiating another cycle of translation. This phenomenon describes ribosomal flow with positive feedback—an increase in the flow of ribosomes terminating translating the open reading frame increases the ribosomal initiation rate. The aim of this paper is to model and rigorously analyse translation with feedback. We suggest a modified version of the ribosome flow model, called the
ribosome flow model with input and output
. In this model, the input is the initiation rate and the output is the translation rate. We analyse this model after closing the loop with a positive linear feedback. We show that the closed-loop system admits a unique globally asymptotically stable equilibrium point. From a biophysical point of view, this means that there exists a unique steady state of ribosome distributions along the mRNA, and thus a unique steady-state translation rate. The solution from any initial distribution will converge to this steady state. The steady-state distribution demonstrates a decrease in ribosome density along the coding sequence. For the case of constant elongation rates, we obtain expressions relating the model parameters to the equilibrium point. These results may perhaps be used to re-engineer the biological system in order to obtain a desired translation rate.
Engineering the acyltransferase substrate specificity of assembly line polyketide synthases
Authors: Dunn Briana J. , Khosla Chaitan
Published: May 2013

Polyketide natural products act as a broad range of therapeutics, including antibiotics, immunosuppressants and anti-cancer agents. This therapeutic diversity stems from the structural diversity of these small molecules, many of which are produced in an assembly line manner by modular polyketide synthases. The acyltransferase (AT) domains of these megasynthases are responsible for selection and incorporation of simple monomeric building blocks, and are thus responsible for a large amount of the resulting polyketide structural diversity. The substrate specificity of these domains is often targeted for engineering in the generation of novel, therapeutically active natural products. This review outlines recent developments that can be used in the successful engineering of these domains, including AT sequence and structural data, mechanistic insights and the production of a diverse pool of extender units. It also provides an overview of previous AT domain engineering attempts, and concludes with proposed engineering approaches that take advantage of current knowledge. These approaches may lead to successful production of biologically active ‘unnatural’ natural products.
Farmer to industrialist: Lister's antisepsis and the making of modern surgery in Germany
Authors: Schlich Thomas
Published: May 2013

This paper analyses what is possibly the most important long-term impact of Joseph Lister's method of antisepsis on surgery, namely its role in replacing surgery's traditional regime of the management of chance by what can be called a regime of modern risk management. It was a crucial step for the expansion of surgery and thus the formation of modern surgery, as we know it today. It put surgery on a par with contemporary trends in industry, transport technologies and science, and made it a component factor in the formation of a modern technology-oriented society. The paper uses the example of the German-speaking countries, which, because of the rapid and emphatic acceptance of Lister's antisepsis there, is particularly well suited for such an analysis. It shows how, in this context, risk management, as a way of dealing with uncertainty, was an integral part of the new techniques of antisepsis and asepsis.
On the fixation probability of superstars
Authors: Díaz Josep , Goldberg Leslie Ann , Mertzios George B. , Richerby David , Serna Maria , Spirakis Paul G.
Published: May 2013

The Moran process models the spread of genetic mutations through populations. A mutant with relative fitness
r
is introduced and the system evolves, either reaching fixation (an all-mutant population) or extinction (no mutants). In a widely cited paper, Lieberman
et al.
(2005 Evolutionary dynamics on graphs.
Nature
433
, 312–316) generalize the model to populations on the vertices of graphs. They describe a class of graphs (‘superstars’), with a parameter
k
and state that the fixation probability tends to 1−
r

−
k

as the graphs get larger: we show that this is untrue as stated. Specifically, for
k
=5, we show that the fixation probability (in the limit, as graphs get larger) cannot exceed 1−1/
j
(
r
), where
j
(
r
)=
Θ
(
r
4
), contrary to the claimed result. Our proof is fully rigorous, though we use a computer algebra package to invert a 31×31 symbolic matrix. We do believe the qualitative claim of Lieberman
et al.
—that superstar fixation probability tends to 1 as
k
increases—and that it can probably be proved similarly to their sketch. We were able to run larger simulations than the ones they presented. Simulations on graphs of around 40 000 vertices do not support their claim but these graphs might be too small to exhibit the limiting behaviour.
RICE SALT SENSITIVE3 Forms a Ternary Complex with JAZ and Class-C bHLH Factors and Regulates Jasmonate-Induced Gene Expression and Root Cell Elongation
Authors: Toda Yosuke , Tanaka Maiko , Ogawa Daisuke , Kurata Kyo , Kurotani Ken-ichi , Habu Yoshiki , Ando Tsuyu , Sugimoto Kazuhiko , Mitsuda Nobutaka , Katoh Etsuko , Abe Kiyomi , Miyao Akio , Hirochika Hirohiko , Hattori Tsukaho , Takeda Shin
Published: May 2013

Plasticity of root growth in response to environmental cues and stresses is a fundamental characteristic of land plants. However, the molecular basis underlying the regulation of root growth under stressful conditions is poorly understood. Here, we report that a rice nuclear factor, RICE SALT SENSITIVE3 (RSS3), regulates root cell elongation during adaptation to salinity. Loss of function of RSS3 only moderately inhibits cell elongation under normal conditions, but it provokes spontaneous root cell swelling, accompanied by severe root growth inhibition, under saline conditions. RSS3 is preferentially expressed in the root tip and forms a ternary complex with class-C basic helix-loop-helix (bHLH) transcription factors and JASMONATE ZIM-DOMAIN proteins, the latter of which are the key regulators of jasmonate (JA) signaling. The mutated protein arising from the rss3 allele fails to interact with bHLH factors, and the expression of a significant portion of JA-responsive genes is upregulated in rss3. These results, together with the known roles of JAs in root growth regulation, suggest that RSS3 modulates the expression of JA-responsive genes and plays a crucial role in a mechanism that sustains root cell elongation at appropriate rates under stressful conditions.
Optical design of the Short Pulse Soft X-ray Spectroscopy beamline at the Advanced Photon Source
Authors: Reininger R. , Keavney D. J. , Borland M. , Young L.
Published: May 2013

The Short Pulse X-ray facility planned for the Advanced Photon Source (APS) upgrade will provide two sectors with photon beams having picosecond pulse duration. The Short Pulse Soft X-ray Spectroscopy (SPSXS) beamline will cover the 150–2000 eV energy range using an APS bending magnet. SPSXS is designed to take full advantage of this new timing capability in addition to providing circular polarized radiation. Since the correlation between time and electron momentum is in the vertical plane, the monochromator disperses in the horizontal plane. The beamline is designed to maximize flux and preserve the time resolution by minimizing the number of optical components. The optical design allows the pulse duration to be varied from 1.5 to 100 ps full width at half-maximum (FWHM) without affecting the energy resolution, and the resolution to be changed with minimal effect on the pulse duration. More than 109 photons s−1will reach the sample with a resolving power of 2000 and a pulse duration of ∼2 ps for photon energies between 150 and 1750 eV. The spot size expected at the sample position will vary with pulse duration and exit slit opening. At 900 eV and at a resolving power of 2000 the spot will be ∼10 µm × 10 µm with a pulse duration of 2.3 ps FWHM.
The review of approaches to knowledge management system studies
Authors: Matayong Sureena , Kamil Mahmood Ahmad
Published: May 2013

Purpose

This paper reviews the current literature of knowledge management systems (KMS) studies in organizations. The authors systematically review the literature according to the principle of innovation studies approach, i.e. variance and process approaches. The purpose of this paper is to identify the current state of KMS studies in organizations. By doing this, the way is paved for the authors to find the research gaps, which would facilatively suggest the direction for future research. The authors hope that this review will be regarded as a source for those who share mutual interests in KMS research and could stimulate further research being conducted in the area with different approaches in the future.

Design/methodology/approach

Journal articles published within the period 2003‐2013 were collected. The articles were sourced mainly from Emerald, Science Direct, IEEE,MIS Quarterly, as well as some other academic databases. The search was conducted using such keywords as “knowledge management system” “knowledge repository” “knowledge management tools” “system for knowledge management” and “knowledge‐based system”.

Findings

It was found that the majority of KMS studies primarily pertain to adoption, diffusion, usage, and implementation, which are fundamentally based on a variance approach. The studies based on a process approach, however, are found to be scarce and still lacking. The authors highlight the findings and provide a critical review of the current approach, as well as commenting on the traditional theories that have been applied, unified, and modified for the studies of KMS in organizations. The authors also suggest some appropriate approaches to studying KMS in organizations and future directions for further research in this field.

Research limitations/implications

The paper has produced a certain result of review studies from the existing literature during the period 2003‐2013. However, the review mainly focused on different approaches that looked into the classification of study schemes and theories being applied for research, while not focusing on other aspects that may be relevant to the area of studies.

Originality/value

The result of this review highlights some gaps in the literature in terms of findings and critical observation of the theoretical and methodological approaches to the research of KMS studies in organizations. Directions for future research are suggested.
Determinants of knowledge sharing in a public sector organization
Authors: Titi Amayah Angela
Published: May 2013

Purpose

The purpose of this paper is to investigate the factors that affect knowledge sharing in a public sector organization.

Design/methodology/approach

The paper is based on quantitative research. The data were gathered through questionnaires and analyzed using multiple regression.

Findings

Community‐related considerations, normative considerations and personal benefits were three motivators found to have a unique contribution to the variance in knowledge sharing. The following enablers had a significant main effect on knowledge sharing: social interaction, rewards, and organizational support. Two barriers, degree of courage and degree of empathy, which measured organizational climate, were found to have a significant main effect on knowledge sharing. The interaction of normative consideration with social interaction, personal benefit with organizational support, and normative considerations with degree of courage, had a moderating effect on the relationship between motivating factors and knowledge sharing.

Research limitations/implications

The study was conducted in a single public sector organization, which limits the generalizability of the findings to other settings. Another limitation is that attitudes toward knowledge sharing, and knowledge‐sharing behaviors, vary across cultures. Finally, self‐reported data are subject to response bias.

Practical implications

Identifying factors that influence knowledge sharing could help practitioners create a knowledge‐sharing culture that is needed to support knowledge sharing and knowledge management within public sector organizations.

Originality/value

This empirical study will contribute to the theoretical knowledge on knowledge sharing in the public sector, which has been neglected in knowledge‐sharing research.
Protection, Resilience and Empowerment: United Nations Peacekeeping and Violence against Civilians in Contemporary War Zones
Authors: Williams Paul D.
Published: May 2013

Civilian protection mandates in United Nations (UN) peacekeeping operations have become increasingly common since 1999. This article suggests that these mandates should be recalibrated to help build resilient local communities and empower civilian populations to have a greater say in their national governance structures. However, while peacekeepers could reasonably give greater emphasis to building local resilience, the empowerment agenda is largely beyond their means. This leaves some UN peacekeeping operations in the perilous position of working to protect civilians at the operational level without addressing some of the key structural conditions that give rise to violence against civilians.
Spatial Integration in the Spanish Mackerel Market
Authors: García‐Enríquez Javier , Hualde Javier , Arteche Josu , Murillas‐Maza Arantza
Published: May 2013

This article analyses the potential links between regional first‐sale markets for mackerel in Spain using fractional cointegration techniques. The results indicate that this is not an integrated market, and we demonstrate that there are no links, at least in the long term, between any of Spain's five regional markets. This result has significant implications in policy terms, as local, regional and European authorities must take into account the need to apply distinct local policies.
Correlation of articular involvement, skin disfigurement and unemployment with depressive symptoms in patients with systemic sclerosis: a hospital sample
Authors: Tedeschini Enrico , Pingani Luca , Simoni Elena , Ferrari Daniela , Giubbarelli Cinzia , Giuggioli Dilia , Lumetti Federica , Rigatelli Marco , Ferri Clodoveo , Ferrari Silvia
Published: May 2013

Background

Systemic sclerosis (SSc) is a connective tissue disease associated with increased functional impairment, body image distress due to skin lesions, and psychosocial comorbidity, particularly depression. Prevalence of depressive symptoms in SSc patients ranges from 36% to 65% and it contributes to the worsening of any aspect of the disease. The aim of this study was to investigate the prevalence and clinical and non‐clinical correlates of depressive symptoms in a sample of outpatients with SSc.

Methods

Seventy‐eight consecutive SSc outpatients were recruited from February 2005 to July 2007. Socio‐demographic and SSc‐related clinical data were collected, including a modified Rodnan Skin Score, the Valentini Disease Activity Index and psycho‐metric assessment of disability and pain. Depressive symptoms were assessed using the Beck Depression Inventory (BDI). Two questions on perception of support from relatives and impact of disfigurements were also directly addressed to subjects.

Results

The BDI mean score was 10.5 (± 8.3), with 36 subjects (46.2%) scoring above clinical significance. Unemployment, increased disability, pain, disease activity and articular involvement were significantly associated with more depressive symptoms. Older age, unemployment and more depressive symptoms were also related with complaints of disfigurements due to skin involvement.

Conclusions

Depression is an influential prognostic factor in SSc. The present study contributes to the knowledge of the relationship between depression and clinical features routinely collected in rheumatology settings in order to develop a standardized assessment of psychosocial distress in routine rheumatologic procedures.
Pemetrexed plus carboplatin as adjuvant chemotherapy in patients with curative resected non‐squamous non‐small cell lung cancer
Authors: Zhang Liang , Ou Wei , Liu Qianwen , Li Ning , Liu Li , Wang Siyu
Published: May 2013

Background

Cisplatin‐based adjuvant chemotherapy provided a significant advantage in the overall survival (OS) of patients with stage II and III non‐small cell lung cancer (NSCLC). However, the compliance and toxicity in cisplatin‐based treatment were not always satisfactory. Pemetrexed plus carboplatin (PC) had better chemotherapy compliance and efficiency in advanced non‐squamous NSCLC patients. The aim of our study was to investigate the feasibility and efficacy of PC as adjuvant chemotherapy in patients with completely resected non‐squamous NSCLC.

Methods

Eighty‐two eligible non‐squamous NSCLC patients operated on with pathological stage II or IIIA were enrolled in this trial. Adjuvant chemotherapy was initiated between one and four weeks after surgery, and consisted of four cycles of pemetrexed (500 mg/m2) plus carboplatin (AUC = 5) every three weeks. The primary endpoint was the compliance of the regimen and the second endpoint was disease‐free survival (DFS).

Results

Patient demographics were median age 58 years (range 32 to 78) and gender ratio 68.3% male/31.7% female. Forty‐eight (58.5%) of the patients were at stage II, and the other thirty‐four (41.5%) patients were at stage IIIA. Seventy patients (85.4%) received four cycles of therapy over a 12‐week period. Reasons for discontinuing therapy included: patient's refusal (n = 10); severe adverse events (n = 1); and surgical complications (n = 1). The primary grade 3 to 4 adverse reaction was hematologic toxicity: neutropenia (13.4%); leucopenia (7.3%); anemia (3.7%); and thrombocytopenia (2.4%). Non‐hematological adverse events were mild. No treatment related deaths were observed. Median DFS for stage II and IIIA patients were 38.0 months (95% confidence interval (CI): 28.1 to 47.9 months) and 21.0 months (95%CI: 13.7 to 28.3 months), respectively.

Conclusion

Adjuvant PC chemotherapy was an acceptable regimen in resected non‐squamous NSCLC patients.
Gambling in Spain: update on experience, research and policy
Authors: Jiménez‐Murcia Susana , Fernández‐Aranda Fernando , Granero Roser , Menchón Jose Manuel
Published: May 2013

Aims

To describe the current situation of gambling in Spain, sketching its history and discussing the regulations and legislation currently in force within the framework of the European Union (EU), and to review the epidemiology of gambling in Spain, the self‐help groups and professional treatments available, and their potential effectiveness.

Methods

A systematic computerized search was performed in three databases (EMBASE, PubMed and PsychINFO, including articles and chapters) and the reference lists from previous reviews to obtain some of the most relevant studies published up to now on the topic of pathologic gambling in Spain.

Results

Similar to other EU countries, Spain has a high prevalence of pathologic gambling, focused on specific culturally bounded types of gambling. Expenditure in online gaming has risen significantly in the last few years, prompting the Spanish government to draft new legislation to regulate gaming.

Conclusions

The gaming industry is expected to be one of the fastest growing sectors in Spain in the coming years owing to the rise of new technologies and the development of online gaming.
Simvastatin local drug delivery in smokers with chronic periodontitis: a randomized controlled clinical trial
Authors: Rao NS , Pradeep AR , Bajaj P , Kumari M , Naik SB
Published: May 2013

Background

Simvastatin (SMV) is a specific competitive inhibitor of 3‐hydroxy‐2‐methyl‐glutaryl coenzyme A reductase. Statins have recently been shown to promote bone formation. This study was designed to investigate the effectiveness of SMV 1.2% in an indigenously prepared biodegradable controlled release gel as an adjunct to scaling and root planing (SRP) in the treatment of smokers with chronic periodontitis.

Methods

Forty patients were categorized into two treatment groups: SRP plus SMV 1.2% and SRP plus placebo. Clinical parameters were recorded at baseline and at 3, 6 and 9 months; they included modified sulcus bleeding index (mSBI), probing depth (PD) and clinical attachment level (CAL). At baseline, after 6 months and 9 months, radiologic assessment of intrabony defect (IBD) fill was done using computer‐aided software.

Results

Mean probing depth reduction and mean clinical attachment level gain was greater in the SMV group than the placebo group at all visits. Furthermore, significantly greater mean percentage of bone fill was found in the SMV group (32.37 ± 10.23%) compared to the placebo (4.18 ± 5.39%).

Conclusions

There was a greater decrease in mSBI and PD and more CAL gain with significant IBD fill at sites treated with SRP plus locally delivered SMV in smokers with chronic periodontitis.
Assessing the impact of menopause on salivary flow and xerostomia
Authors: Minicucci EM , Pires RBC , Vieira RA , Miot HA , Sposto MR
Published: May 2013

Background

The aim of this study was to evaluate the symptoms of dry mouth and salivary flow in menarche and menopausal women.

Methods

Objective and subjective assessment of salivary function were analysed by Xerostomia Inventory and Visual Analogue Scale questionnaire in menopausal and menarche women (control group). Salivary flow was evaluated by a chemical absorption stimulation test. Each subject provided three saliva samples: S1, non‐stimulated saliva; S2, saliva initially stimulated with two drops of citric acid 2.5%; and S3, saliva super‐stimulated with two drops of citric acid 2.5% every 30 seconds for two minutes.

Results

No intergroup association was observed between Xerostomia Inventory and Visual Analogue Scale questionnaire. In both groups, the salivary flow was greatest at S3, followed by S2 and finally S1. Salivary flow was lower in the menopausal group compared to the control group only in S2 and S3.

Conclusions

In the menopausal group, the salivary flow showed reduction but without clinical symptoms of dry mouth. It is important to normalize salivary flow to prevent oral abnormalities and maintain oral health.
Partial luxation and displacement of tooth during treatment of malocclusion using light‐wire fixed appliances – therapeutic procedure
Authors: Malinowska‐Jedraszczyk A , Wozniak K
Published: May 2013

Facial trauma sustained during an accident by a 17‐year‐old female patient who wore thin‐wire fixed appliances caused partial luxation and displacement of tooth 21. Because it was attached to a fixed appliance, the tooth did not lose contact with the socket, which significantly improved the prognosis. This study describes the method, course and result of the treatment carried out over a two‐year period after the trauma occurred.
Evaluation of air‐particle abrasion of Y‐TZPwith different particles using microstructural analysis
Authors: Turp V , Sen D , Tuncelli B , Goller G , Özcan M
Published: May 2013

Background

This study evaluated the effect of air‐particle abrasion with different particle sizes on the surface roughness and phase transformation of yttria‐stabilized tetragonal zirconia ceramics (Y‐TZP).

Methods

Eighty‐four Y‐TZPdiscs of 15 mm diameter and 1.0 mm thickness were fabricated. The samples were divided into four groups (n = 21): (1) air‐particle abrasion with 30 μm CoJet sand blast coating agent (CoJet, 3MESPE); (2) 50 μm Al2O3particles; (3) 110 μm Al2O3particles; and (4) 250 μm Al2O3particles. Each group was further divided into three subgroups each (n = 7) and treated for 5 seconds, 15 seconds and 30 seconds. Mean surface roughness was determined using a profilometer. The surfaces were analysed with a scanning electron microscope.XRDanalysis was employed and the relative amount of the monoclinic phase was calculated. The results were statistically analysed by two‐way analysis of variance (ANOVA, p < 0.05).

Results

Air‐particle abrasion with 250 μm Al2O3particles for 30 seconds had the highest surface roughness (p < 0.001) and a significantly higher amount of monoclinic phase compared to air‐particle abrasion with 30 μm, 50 μm and 110 μm particles (p < 0.001).

Conclusions

Duration and particle size of air‐particle abrasion affects the roughness and phase transformation of Y‐TZP. Longer treatment times with larger particles may result in degradation of material.