bluuebunny/crossref_metadata_2025 huggingface dataset:
How to compare diffusion processes assessed by single-particle tracking and pulsed field gradient nuclear magnetic resonance
Authors: Bauer Michael , Valiullin Rustem , Radons Günter , Kärger Jörg
Published: October 2011

Heterogeneous diffusion processes occur in many different fields such as transport in living cells or diffusion in porous media. A characterization of the transport parameters of such processes can be achieved by ensemble-based methods, such as pulsed field gradient nuclear magnetic resonance (PFG NMR), or by trajectory-based methods obtained from single-particle tracking (SPT) experiments. In this paper, we study the general relationship between both methods and its application to heterogeneous systems. We derive analytical expressions for the distribution of diffusivities from SPT and further relate it to NMR spin-echo diffusion attenuation functions. To exemplify the applicability of this approach, we employ a well-established two-region exchange model, which has widely been used in the context of PFG NMR studies of multiphase systems subjected to interphase molecular exchange processes. This type of systems, which can also describe a layered liquid with layer-dependent self-diffusion coefficients, has also recently gained attention in SPT experiments. We reformulate the results of the two-region exchange model in terms of SPT-observables and compare its predictions to that obtained using the exact transformation which we derived.
Ferroic switching, avalanches, and the Larkin length: Needle domains in LaAlO3
Authors: Harrison Richard J. , Salje Ekhard K. H.
Published: October 2011

Propagation of wedge-shaped needle domains in LaAlO3 is driven mechanically and the change of wall shapes is observed. Twin walls remain smooth, whereas the one-dimensional front line of the needle tip shows “wiggles” when propagating through defect fields. The front line becomes highly distorted during approach to, or retraction from, the sample surface. Singularities of the characteristic (∼Larkin) length occur when the front line breaks. Elastic forces produce planar twin walls with very large Larkin lengths, whereas the front line is not restrained by the compatibility energy and displays considerably shorter Larkin lengths.
Simulations of the effect of waveguide cross-section on quantum dot–plasmon coupling
Authors: Vernon K. C. , Gomez D. E. , Davis T. J. , Tischler N.
Published: October 2011

Quantum dot–plasmon waveguide systems are of interest for the active control of plasmon propagation, and consequently, the development of active nanophotonic devices such as nano-sized optical transistors. This paper is concerned with how varying aspect ratio of the waveguide cross-section affects the quantum dot–plasmon coupling. We compare a stripe waveguide with an equivalent nanowire, illustrating that both waveguides have a similar coupling strength to a nearby quantum dot for small waveguide cross-section, thereby indicating that stripe lithographic waveguides have strong potential use in quantum dot–plasmon waveguide systems. We also demonstrate that changing the aspect ratio of both stripe and wire waveguides can increase the spontaneous emission rate of the quantum dot into the plasmon mode, by up to a factor of five. The results of this paper will contribute to the optimisation of quantum dot–plasmon waveguide systems and help pave the way for the development of active nanophotonics devices.
Electrical control of photoluminescence wavelength from semiconductor quantum dots in a ferroelectric polymer matrix
Authors: Korlacki Rafał , Saraf Ravi F. , Ducharme Stephen
Published: October 2011

We report controllable tuning of the room temperature photoluminescence band of CdSe semiconductor quantum dots embedded in thin films of ferroelectric copolymer of vinylidene fluoride and trifluoroethylene made by Langmuir-Blodgett deposition. The high breakdown strength of the polymer permits the application of electric fields of up to 400 MV/m and results in a shift in the photoluminescence peak by up to 9 nm, nearly half the fluorescence band width. Moreover, we found that at these high electric fields, the Stark effect exhibits unusual fourth power dependence.
Shear horizontal surface acoustic wave induced microfluidic flow
Authors: Brodie D. S. , Fu Y. Q. , Li Y. , Alghane M. , Reuben R. L. , Walton A. J.
Published: October 2011

In this letter, we demonstrate that surface acoustic waves (SAWs) excited on 36°Y-X LiTaO3 have both Rayleigh and shear horizontal components, which can result in different acoustic streaming patterns in micro-droplets. The shear horizontal surface acoustic wave streaming pattern exhibits a quasi-stable counterflow in the SAW propagation direction with velocities of up to 16 mm/s, with minimal damping observed within the droplets. A pumping function was realized at a threshold power of 30 dBm with a large rotation vector on hydrophobically treated devices.
Origin of the dark-current ideality factor in polymer:fullerene bulk heterojunction solar cells
Authors: Wetzelaer G. A. H. , Kuik M. , Lenes M. , Blom P. W. M.
Published: October 2011

In organic bulk heterojunction solar cells, a deviation of the ideality factor of the dark current from unity is commonly put forward as evidence for the presence of trap-assisted recombination. We demonstrate that the non-ideality of the dark characteristics is determined by deeply trapped carriers in the transport-dominating constituent of the donor:acceptor blend, rather than a trap-assisted recombination mechanism. The light-intensity dependence of the open-circuit voltage confirms the absence of trap-assisted recombination and demonstrates that the dominant recombination mechanism in the investigated polymer:fullerene solar cells is bimolecular.
ZnO nanowire transistor inverter using top-gate electrodes with different work functions
Authors: Tack Lee Young , Keun Kim Jong , Ha Ryong , Choi Heon-Jin , Im Seongil
Published: October 2011

ZnO-nanowire field effect transistors (FETs) with a top gate Al2O3 dielectric and different metal electrodes were fabricated to form a low voltage electrical inverter. Two FETs with Pd and Ni/Ti gates whose respective work functions are so different as 5.3 and 4.3 eV were chosen to play as driver and load, since such different work functions lead to a threshold voltage (VT) difference of at least 1 V between the two FETs. Our FETs with Pd and Ni/Ti, respectively, showed 0.8 and −0.3 V for their VT values, while our inverter exhibited a desirable voltage transfer characteristics with voltage gain of over 15 during low voltage electrical gating.
Thermal emittance and response time of a cesium antimonide photocathode
Authors: Cultrera Luca , Bazarov Ivan , Bartnik Adam , Dunham Bruce , Karkare Siddharth , Merluzzi Richard , Nichols Matthew
Published: October 2011

Measurements of the intrinsic emittance and response time of a Cs3Sb photocathode are presented. The emittance is obtained with a solenoid scan technique using a high voltage dc photoemission gun. Photoemission response time is evaluated using a RF deflecting cavity synchronized to a picosecond laser pulse train. We find that Cs3Sb has both small mean transverse energy, 160 ± 10 meV at 532 nm laser wavelength, and a prompt response time (below the resolution of our measurement) making it a suitable material for high brightness electron photoinjectors.
Complexity of homeowner wildfire risk mitigation: an integration of hazard theories
Authors: McFarlane Bonita L. , McGee Tara K. , Faulkner Hilary
Published: October 2011

Each year wildfire affects communities in Canada, resulting in evacuations and, in some cases, loss of homes. Several Canadian wildfire management agencies have initiated mitigation programs aimed at reducing wildfire risk. Successful wildfire mitigation involves both community-level and homeowner action. This paper examines factors that influence wildfire mitigation by homeowners. We draw upon the general hazards and wildfire management literature to develop and test a theoretical model for homeowner wildfire mitigation that includes perceived risk, an evaluation of threat significance and the influence of perceived costs and benefits of mitigation. We used a mail survey to collect data from 1265 residents in six interface communities in the province of Alberta. Results showed a high level of completion for most mitigation activities. A structural equation model provided support for the hypothesis that the evaluation of threat involves weighing the negative effects of mitigation on homeowners’ feelings of connectedness to nature and the cost of mitigation with the positive influences of fear, a sense of responsibility and perceived effectiveness of mitigation. Considering the total effects, threat assessment had the greatest effect on mitigation by homeowners, followed by perceived effectiveness of mitigation in reducing damage and not having financial resources for mitigation.
Behaviour and effects of prescribed fire in masticated fuelbeds
Authors: Knapp Eric E. , Varner J. Morgan , Busse Matt D. , Skinner Carl N. , Shestak Carol J.
Published: October 2011

Mechanical mastication converts shrub and small tree fuels into surface fuels, and this method is being widely used as a treatment to reduce fire hazard. The compactness of these fuelbeds is thought to moderate fire behaviour, but whether standard fuel models can accurately predict fire behaviour and effects is poorly understood. Prescribed burns were conducted in young ponderosa pine (Pinus ponderosa Laws.) forests at two sites in northern California where the midstorey layer dominated by shrubs had been masticated. Surface fuels were raked from the base of a subset of trees before burning. Rate of spread and flame length were estimated for both backing and heading fires, soil heating measured with thermocouples and tree fire injury recorded. Standard fuel models often over-predicted rate of spread or under-predicted flame length. Custom models generally provided a better balance between the slow rates of spread and moderate flame lengths observed in prescribed burns. Post-fire tree mortality was most strongly associated with crown scorch and tree size; raking fuels from the base of trees did not improve survival. Under severe fire weather conditions, fire behaviour and effect models as well as observations from wildfires suggest that mastication may be more effective for moderating fire behaviour than reducing residual tree mortality. Treating masticated fuels with prescribed burns could potentially improve the resilience of stands to wildfire.
Soil N2O emissions in a Mediterranean shrubland disturbed by experimental fires
Authors: Fierro Angelo , Castaldi Simona
Published: October 2011

In the present work, post-burning soil N2O fluxes and related microbial processes were investigated in a Mediterranean shrubland subjected to experimental fires. Nine plots were selected, of which three were used as controls, three were burned with low-intensity fire and three with higher intensity fire. N2O fluxes, soil humidity and temperature were measured starting 2 days before burning and for 1 year after fire. Potential net nitrification, denitrification enzyme activity, mineral N and organic C were measured from soil samples collected periodically after burning. Cumulative data indicate a doubling of N2O production in burned plots over 1 year. Burned plots showed an increase of frequency of hot spots of N2O production. A slight detrimental effect of fire on the analysed biological activities was detected only immediately after burning. After 3 months, both potential net nitrification and denitrification enzyme activity had mostly recovered and potential net nitrification further increased over control levels in the following months. Fire seemed to induce a change in the main source of N2O, which in control plots was represented by heterotrophic activity (50–75%), whereas in burned plots it was mostly of autotrophic origin, most probably due to the significant increase of soil NH4+ after burning.
Mitochondrial Ribosomal Protein L12 selectively associates with human mitochondrial RNA polymerase to activate transcription
Authors: Surovtseva Yulia V. , Shutt Timothy E. , Cotney Justin , Cimen Huseyin , Chen Sophia Y. , Koc Emine C. , Shadel Gerald S.
Published: October 2011

Basal transcription of human mitochondrial DNA (mtDNA) in vitro requires the single-subunit, bacteriophage-related RNA polymerase, POLRMT, and transcription factor h-mtTFB2. This two-component system is activated differentially at mtDNA promoters by human mitochondrial transcription factor A (h-mtTFA). Mitochondrial ribosomal protein L7/L12 (MRPL12) binds directly to POLRMT, but whether it does so in the context of the ribosome or as a “free” protein in the matrix is unknown. Furthermore, existing evidence that MRPL12 activates mitochondrial transcription derives from overexpression studies in cultured cells and transcription experiments using crude mitochondrial lysates, precluding direct effects of MRPL12 on transcription to be assigned. Here, we report that depletion of MRPL12 from HeLa cells by shRNA results in decreased steady-state levels of mitochondrial transcripts, which are not accounted for by changes in RNA stability. We also show that a significant “free” pool of MRPL12 exists in human mitochondria not associated with ribosomes. “Free” MRPL12 binds selectively to POLRMT in vivo in a complex distinct from those containing h-mtTFB2. Finally, using a fully recombinant mitochondrial transcription system, we demonstrate that MRPL12 stimulates promoter-dependent and promoter-independent transcription directly in vitro. Based on these results, we propose that, when not associated with ribosomes, MRPL12 has a second function in transcription, perhaps acting to facilitate the transition from initiation to elongation. We speculate that this is one mechanism to coordinate mitochondrial ribosome biogenesis and transcription in human mitochondria, where transcription of rRNAs from the mtDNA presumably needs to be adjusted in accordance with the rate of import and assembly of the nucleus-encoded MRPs into ribosomes.
Sequential Monte Carlo multiple testing
Authors: Sandve Geir Kjetil , Ferkingstad Egil , Nygård Ståle
Published: October 2011

Motivation: In molecular biology, as in many other scientific fields, the scale of analyses is ever increasing. Often, complex Monte Carlo simulation is required, sometimes within a large-scale multiple testing setting. The resulting computational costs may be prohibitively high.

Results: We here present MCFDR, a simple, novel algorithm for false discovery rate (FDR) modulated sequential Monte Carlo (MC) multiple hypothesis testing. The algorithm iterates between adding MC samples across tests and calculating intermediate FDR values for the collection of tests. MC sampling is stopped either by sequential MC or based on a threshold on FDR. An essential property of the algorithm is that it limits the total number of MC samples whatever the number of true null hypotheses. We show on both real and simulated data that the proposed algorithm provides large gains in computational efficiency.

Availability: MCFDR is implemented in the Genomic HyperBrowser (http://hyperbrowser.uio.no/mcfdr), a web-based system for genome analysis. All input data and results are available and can be reproduced through a Galaxy Pages document at: http://hyperbrowser.uio.no/mcfdr/u/sandve/p/mcfdr.

Contact:  geirksa@ifi.uio.no
BDTcomparator: a program for comparing binary classifiers
Authors: Fijorek Kamil , Fijorek Damian , Wisniowska Barbara , Polak Sebastian
Published: October 2011

Summary: The BDTcomparator facilitates the selection of the best performing binary classification model or binary diagnostic procedure from the many possible alternatives by comparing their predictions with a known output, measured with the use of a system recognized as the gold standard. The program calculates the estimates of accuracy, sensitivity, specificity, predictive values and diagnostic likelihood ratios along with appropriate confidence intervals. Furthermore, all pairwise comparisons with respect to the above-mentioned measures are calculated. The formatted results can be exported to a text-file.

Availability and Implementation: BDTcomparator is distributed under the GNU GPLv3 license and is freely available for download from http://www.tox-portal.net. We provide programs for both Linux and Windows operating systems. The source code of the program is provided in our companion website http://code.google.com/p/bdtcomparator/.

Contact:  kamil.fijorek@uek.krakow.pl

Supplementary Information:  Supplementary data are available at Bioinformatics online.
Entropy Balancing for Causal Effects: A Multivariate Reweighting Method to Produce Balanced Samples in Observational Studies
Authors: Hainmueller Jens
Published: October 2011

This paper proposes entropy balancing, a data preprocessing method to achieve covariate balance in observational studies with binary treatments. Entropy balancing relies on a maximum entropy reweighting scheme that calibrates unit weights so that the reweighted treatment and control group satisfy a potentially large set of prespecified balance conditions that incorporate information about known sample moments. Entropy balancing thereby exactly adjusts inequalities in representation with respect to the first, second, and possibly higher moments of the covariate distributions. These balance improvements can reduce model dependence for the subsequent estimation of treatment effects. The method assures that balance improves on all covariate moments included in the reweighting. It also obviates the need for continual balance checking and iterative searching over propensity score models that may stochastically balance the covariate moments. We demonstrate the use of entropy balancing with Monte Carlo simulations and empirical applications.
LPS‐binding Protein Enables Intestinal Epithelial Restitution Despite LPS Exposure
Authors: Richter Juli M. , Schanbacher Brandon L. , Huang Hong , Xue Jianjing , Bauer John A. , Giannone Peter J.
Published: October 2011

Objectives:

Intestinal epithelial restitution is the first part in the process of mucosal repair after injury in the intestine. Integrity of the intestinal mucosal barrier is important as a first line of defense against bacteria and endotoxin. Necrotizing enterocolitis (NEC) is a major cause of morbidity and mortality in extremely‐low‐birth‐weight infants, but its mechanisms are not well defined. Abnormal bacterial colonization, immature barrier function, innate immunity activation, and inflammation likely play a role. Lipopolysaccharide (LPS)‐binding protein (LBP) is secreted by enterocytes in response to inflammatory stimuli and has concentration‐dependent effects. At basal concentrations, LBP stimulates the inflammatory response by presenting LPS to its receptor; however, at high concentrations, LBP is able to neutralize LPS and prevent an exaggerated inflammatory response. We sought to determine how LBP would affect wound healing in an in vitro model of intestinal cell restitution and protect against intestinal injury in a rodent model of NEC.

Methods:

Immature intestinal epithelial cells (IEC‐6) were seeded in poly‐L‐lysine–coated 8‐chamber slides and grown to confluence. A 500‐μm wound was created using a cell scraper mounted on the microscope to achieve uniform wounding. Media was replaced with media containing LPS ± LBP. Slide wells were imaged after 0, 8, and 24 hours and then fixed. Cellular restitution was evaluated via digital images captured on an inverted microscope and wound closure was determined by automated analysis. Toll‐like receptor 4 (TLR4) was determined by reverse transcriptase‐polymerase chain reaction after RNA isolation from wounded cells 24 hours after treatment.

Results:

LPS alone attenuated wound healing in immature intestinal epithelium. This attenuation is reversed by 24 hours with increasing concentrations of LBP so that wound healing is equivalent to control (P < 0.001). TLR4 was increased with LPS alone but levels returned to that of control after addition of LBP in the higher concentrations. LBP had no effect on the development of intestinal injury when given during our rodent model of NEC. Abnormal bacterial colonization and activation of innate immunity by LPS are likely involved in the pathogenesis of NEC.

The attenuation of wound healing was reversed when LBP was added to LPS but only in the higher concentrations. At these same concentrations of LBP, TLR4 was decreased to that of control.

Conclusions:

These results indicate that LBP may be a novel therapeutic strategy to facilitate wound healing after the acute phase of NEC and other forms of intestinal injury.
Risk Factors Associated With Biliary Pancreatitis in Children
Authors: Ma Michael H. , Bai Harrison X. , Park Alexander J. , Latif Sahibzada U. , Mistry Pramod K. , Pashankar Dinesh , Northrup Veronika S. , Bhandari Vineet , Husain Sohail Z.
Published: October 2011

Objectives:

Little is known about risk factors for biliary pancreatitis in children. We characterized cases of pediatric biliary pancreatitis, compared biliary with nonbiliary cases, examined differences in presentation between younger and older children, and studied features distinguishing gallstone‐ from sludge‐induced pancreatitis.

Methods:

We evaluated 76 episodes of biliary pancreatitis from 271 cases of acute pancreatitis in children admitted to a tertiary care hospital from 1994 to 2007.

Results:

Of the 76 cases, 55% had gallstones, 21% had sludge, and 24% had structural defects. Hispanic children had 2.85 (P = 0.01) and 5.59 (P = 0.003) times higher probability for biliary pancreatitis than white and black children, respectively. Median serum amylase and lipase in children with biliary pancreatitis were 64% and 49% higher, respectively, compared with other causes (P < 0.05). In multiple logistic regression, aspartate aminotransferase was an independent predictor of biliary pancreatitis (odds ratio 6.69, P = 0.001). When comparing gallstone‐ with sludge‐induced causes, obesity was an independent predictor (38% more prevalent, P < 0.01) of gallstone cases.

Conclusions:

Hispanic ethnicity is a risk factor and aspartate aminotransferase is a biomarker for biliary pancreatitis over other causes. Furthermore, obesity can distinguish gallstone‐ from sludge‐induced pancreatitis. These findings may spur prospective studies to determine the optimal evaluation and management of children with biliary pancreatitis.
Enterococcus lactis sp. nov., from Italian raw milk cheeses
Authors: Morandi Stefano , Cremonesi Paola , Povolo Milena , Brasca Milena
Published: October 2011

Ten atypical

Enterococcus

strains were isolated from Italian raw milk cheeses. The 16S rRNA gene, phenylalanyl-tRNA synthase alpha subunit (pheS), RNA polymerase alpha subunit (rpoA) and the 16S–23S rRNA intergenic transcribed spacer (ITS) sequences, randomly amplified polymorphic DNA (RAPD) PCR and the phenotypic properties revealed that the isolates represent a novel enterococcal species. On the basis of 16S rRNA gene sequence analysis, the isolates were closely related to

Enterococcus hirae

ATCC 8043T,

Enterococcus durans

CECT 411T and

Enterococcus faecium

ATCC 19434T, with 98.8, 98.9 and 99.4 % sequence similarity, respectively. On the basis of sequence analysis of the housekeeping gene pheS, the reference strain, BT159T, occupied a position separate from

E. faecium

LMG 16198. The group of isolates could be easily differentiated from recognized species of the genus

Enterococcus

by 16S–23S rRNA ITS analysis, RAPD-PCR and phenotypic characteristics. The name Enterococcus lactis sp. nov. is proposed, with BT159T ( = DSM 23655T = LMG 25958T) as the type strain.
Halanaerobacter jeridensis sp. nov., isolated from a hypersaline lake
Authors: Mezghani M. , Alazard D. , Karray F. , Cayol J.-L. , Joseph M. , Postec A. , Fardeau M.-L. , Tholozan J.-L. , Sayadi S.
Published: October 2011

An obligatory anaerobic, moderately halophilic bacterium, designated strain CEJFG43T, was isolated from a sample of sediment collected below the salt crust on the hypersaline El Jerid lake, in southern Tunisia. The cells of this novel strain were Gram-staining-negative, non-sporulating, motile, short rods. They grew in media with 6–30 % (w/v) NaCl (optimum 15 %), at 20–60 °C (optimum 45 °C) and at pH 5.5–9.5 (optimum pH 8.3). The micro-organism fermented glucose, fructose, ribose, raffinose, galactose, mannose, sucrose, maltose, xylose, mannitol, pyruvate and glycerol. The products of glucose fermentation were lactate, ethanol, acetate, H2 and CO2. The genomic G+C DNA content of strain CEJFG43T was 33.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CEJFG43T belonged in the genus

Halanaerobacter

and was most closely related to

Halanaerobacter lacunarum

DSM 6640T (95.3 % gene sequence similarity) and

Halanaerobacter chitinivorans

DSM 9569T (95.3 %). The predominant cellular fatty acids were non-branched (C16 : 0 and C16 : 1). Based on the phylogenetic and phenotypic evidence, strain CEJFG43T represents a novel species in the genus

Halanaerobacter

for which the name Halanaerobacter jeridensis sp. nov. is proposed. The type strain is CEJFG43T ( = DSM 23230T = JCM 16696T).
Oceanisphaera arctica sp. nov., isolated from Arctic marine sediment, and emended description of the genus

Oceanisphaera
Authors: Srinivas T. N. R. , Reddy P. Vishnu Vardhan , Begum Z. , Manasa P. , Shivaji S.
Published: October 2011

A novel Gram-staining-negative, coccoid, non-motile bacterium, designated strain V1-41T, was isolated from a sample of marine sediment collected, at a depth of 200 m, from Kongsfjorden (an inlet on the west coast of Spitsbergen, an island that forms part of the Svalbard archipelago in the Arctic Ocean). The strain formed cream–brown colonies on marine agar. Cells of the novel strain were positive in tests for catalase, oxidase, lysine decarboxylase and ornithine decarboxylase activities but negative for gelatinase and lipase activities. They hydrolysed aesculin, starch and urea, but not casein or DNA. Most of the cellular fatty acids were medium-chain and saturated (37.1 %) or long-chain and unsaturated (27.8 %), with C12 : 0 (37.1 %), C18:1ω7c, and summed features 2 (19.3%) and 3 (24.1%) predominating. The major respiratory quinone was Q-8. The polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, two unidentified aminophospholipids, four unidentified phospholipids and one other unidentified lipid. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel strain’s closest known relatives were

Oceanisphaera litoralis

DSM 15406T (98.5 % sequence similarity) and

Oceanisphaera donghaensis

BL1T (98.3 %). In DNA–DNA hybridizations, however, the levels of relatedness between strain V1-41T and

O. litoralis

DSM 15406T and between the novel strain and

O. donghaensis

DSM 17589T were found to be only 19 % and 29 %, respectively. Based on these low levels of similarity at the DNA–DNA level and the phenotypic and chemotaxonomic differences from

O. litoralis

DSM 15406T and

O. donghaensis

DSM 17589T, strain V1-41T represents a novel species of the genus

Oceanisphaera

for which the name Oceanisphaera arctica sp. nov. is proposed. The type strain is V1-41T ( = CCUG 58690T = KCTC 23013T = NBRC 106171T).
Structural basis for histone H3 Lys 27 demethylation by UTX/KDM6A
Authors: Sengoku Toru , Yokoyama Shigeyuki
Published: October 2011

Tri- and dimethylations of histone H3K9 (H3K9me3/2) and H3K27 (H3K27me3/2), both situated in the “A-R-Kme-S” sequence motif, mediate transcriptional repression of distinct genomic regions. H3K9me3/2 mainly governs constitutive heterochromatin formation, while H3K27me3/2 represses key developmental genes. The mechanisms by which histone-modifying enzymes selectively regulate the methylation states of H3K9 and H3K27 are poorly understood. Here we report the crystal structures of the catalytic fragment of UTX/KDM6A, an H3K27me3/2-specific demethylase, in the free and H3 peptide-bound forms. The catalytic jumonji domain binds H3 residues 25–33, recognizing H3R26, H3A29, and H3P30 in a sequence-specific manner, in addition to H3K27me3 in the catalytic pocket. A novel zinc-binding domain, conserved within the KDM6 family, binds residues 17–21 of H3. The zinc-binding domain changes its conformation upon H3 binding, and thereby recognizes the H3L20 side chain via a hydrophobic patch on its surface, which is inaccessible in the H3-free form. Mutational analyses showed that H3R17, H3L20, H3R26, H3A29, H3P30, and H3T32 are each important for demethylation. No other methyllysines in the histone tails have the same set of residues at the corresponding positions. Thus, we clarified how UTX discriminates H3K27me3/2 from the other methyllysines with distinct roles, including the near-cognate H3K9me3/2, in histones.
Scholarly impact measurements of LIS open access journals: based on citations and links
Authors: Yuan Shunbo , Hua Weina
Published: October 2011

Purpose

The main purpose of this paper is to measure the scholarly impact of LIS (Library and Information Science) open access journals (OA journals), most of which are not indexed by the Web of Science (WoS). In addition, the paper seeks to discuss measurement methods beyond citation analysis.

Design/methodology/approach

The study selected 97 LIS OA journals as a sample and measured their scholarly impact on the basis of citations and links. The citation counts in WoS, coverage in LISA, Web links, WIFs and Page Rank of the journals are retrieved and calculated, and correlations between citation counts, links, pages, WIFs, and Page Rank are also analyzed.

Findings

The results indicate that LIS OA journals have become a significant component of the scholarly communication system. TheJournal of the Medical Library Associationenjoys the highest citation counts in WoS. This journal, together withD‐Lib Magazine,Information Research,Ariadne, Cybermetrics, andFirst Mondayare the six most important LIS OA journals. With regard to coverage in LISA,Bulletin des Bibliothèques de France(2151) performs best. As a whole, the Page Rank is relatively high, mostly at 6, 7, or 8. The study finds that correlation between citation‐based measurements and link‐based measurements tends to be significant.

Originality/value

This paper uses the web as a global resource to measure the impact of LIS OA journals by analyzing citation, coverage, web links and Page Rank. The focus of this study is the value of the web as a source of impact indices, rather different from the traditional research methods. It contributes to the scholarly impact measurements of OA journals.
Determinants of digitally instigated insurance relationships
Authors: Gidhagen Mikael , Gebert Persson Sabine
Published: October 2011

Purpose

The purpose of this paper is to develop a conceptual model for explaining insurance customers' intentions towards using the internet as a channel for communication and interaction with insurance companies by integrating Technology Acceptance Model (TAM) and trust.

Design/methodology/approach

The paper seeks to conceptually develop an integrated framework for studying and measuring the perceptions of customers towards using the internet as a source of communication and interaction. The TAM model is taken as a point of departure where trust and trustworthiness, being essential in insurance relationships, have been included in the model. Trust is divided into perceived competence, perceived benevolence and perceived integrity, which in turn affect whether the customer will find the firm trustworthy or not. A second dimension that is developed in this paper is the disposition to trust, which is defined as a customer‐related factor. This disposition to trust is in turn affected by the customer's internet knowledge and product knowledge.

Findings

The paper contributes by developing the model for understanding and explaining factors that affect customers' attitudes and intentions towards on‐line interactions. By emphasizing internet‐, customer‐ and Ffrm‐related factors, it would arguably be possible to explain factors that affect trust, and trustworthiness, as well as the customer's attitudes towards the organization and the communication and distribution channel while also integrating the customer‐specific factors.

Research limitations

The model developed in this paper is conceptual and needs to be tested empirically.

Originality/value

The findings of this paper will serve as a basis for further research aiming at answering the research question on what factors affect customers' attitudes towards using the internet as an interface within the financial services sector. It also contributes to practices by identifying and defining factors that can affect trust in relationships as well as the choice of communication and distribution channels depending on customers' attitudes.
University librarians respond to changes in higher education: example of a medical school
Authors: Chang Sung‐Shan , Chen Kuan‐nien
Published: October 2011

Purpose

The purpose of this paper is to discuss three recent changes in higher education – the addition of technology to every aspect of the curriculum, the increase in the availability of electronic resources, and the introduction of constructivist pedagogy. In light of these changes, the authors aim to explore what university libraries and librarians should reinforce in terms of their concepts and competency and adjust the ways that they serve students.

Design/methodology/approach

The authors analyze the related literature and identified technology, electronic resources, and constructivist pedagogy that interact with the new curriculum of universities in a broader way than in the past.

Findings

The three dimensions, separately and in combination, require considerable adjustments by librarians, teachers, students, and the school/university community in general. Collaboration among all members of staff, particularly between librarians and teachers, is essential. The emerging paradigm, still firmly based in constructivist principles, recognizes that there is a need for staff guidance of students though they are expected to become increasingly independent as they progress through the system. Meanwhile, two new core competencies have emerged for university librarians: information literacy and problem‐based learning (PBL).

Originality/value

The emergence of the two competencies has reminded librarians to learn, change and grow constantly to serve PBL students effectively.
Is social software really a “killer app” in the education of net generation students? Findings from a case study
Authors: Feuer Gabor
Published: October 2011

Purpose

Social software is increasingly viewed as the new “killer application” in higher education – a potential answer to needs ranging from active learning and student engagement, to faculty empowerment. The purpose of this study is to explore this potential in the context of participating net generation students in a science and technology oriented, laptop‐based university located in Southern Ontario. The study is interested in the efficacy and pedagogical impact of social software (SSW) technologies in the students' learning experience.

Design/methodology/approach

The research model used an exploratory, descriptive, quantitative case study. The focus of the study was on the impacts of SSW on students' information literacy skills. A quasi‐experimental model was used to compare the effects of SSW use in information literacy instruction with those of traditional educational technologies such as learning management systems (LMS).

Findings

A total of 80 students participated. Twenty‐four students in the treatment group used SSW during the instruction phase, while in the control group, 56 used the LMS. The pre‐test showed a relatively moderate use of SSW technologies among the participants, with the exception of social networking technologies. At the completion of the study, students showed moderate willingness to employ SSW to enhance their learning. Barriers to the adoption of these technologies were highlighted. The study findings could not demonstrate that the use of SSW, compared with more established technologies such as the LMS would lead to different information literacy scores.

Originality/value

This is a summary of my original PhD research completed in 2009. A shorter poster version was presented at the 2011 IATUL Conference in June 2011 at Warsaw, Poland.
The impact of relationship quality on attitude toward a sponsor
Authors: Kyoum Kim Yu , Jae Ko Yong , James Jeffery
Published: October 2011

Purpose

The purpose of the current study is to advance understanding of sponsorship effectiveness by investigating the impact of the quality of the relationship between a consumer and a sport property on sponsorship effectiveness.

Design/methodology/approach

A model was developed to examine linkages among relationship quality, sincerity, attitude toward sponsor and intention to purchase a sponsor's product. The measurement model was tested using confirmatory factory analysis. The relationships in the hypothesized model were tested using simultaneous equations.

Findings

The results indicate that positive attitude toward a sponsor and intention to purchase said sponsor's product(s) are more likely to occur among the customers who perceive a higher degree of relationship quality with the sport property and believe the sponsor motives are sincere.

Research limitations/implications

A conceptual model of sponsorship effectiveness was developed and empirically tested. The tested model provides an expanded view of relationship quality and its impact on key variables of sponsorship effectiveness.

Practical implications

Provided in this study is a framework for both sponsors and sport teams that can be used to understand some of the ways in which sponsorship works. The findings suggest that sponsors should leverage their activities to communicate sincere motives, not just “doing business”. For the sport property, the implication is developing quality relationships with consumers, and being able to promote such relationships to prospective sponsors.

Originality/value

Relationship quality has been previously shown to influence various behavioral aspects related to partners in business‐to‐business relationships. This study extends the literature by examining the effect of business‐to‐consumer relationship quality on the expected outcomes associated with a business‐to‐business relationship.
The influence of sport leagues on the business‐to‐business marketing of teams: the case of professional road cycling
Authors: Benijts Tim , Lagae Wim , Vanclooster Benedict
Published: October 2011

Purpose

This study seeks to examine how a sport league, a unique feature of professional sport, influences the business‐to‐business marketing of teams participating in the sport league.

Design/methodology/approach

This study uses a qualitative research design based on a single case study, the UCI ProTour in professional road cycling. The primary sources consist of 27 semi‐structured interviews complemented by written sources and controlled for construct validity, external validity and reliability.

Findings

From a theoretical point of view, a sport league is a marketing channel network (a specific type of an intentionally developed business network or IDBN). Theoretical analysis also reveals that the teams' business‐to‐business marketing is positively related to the network's value‐creating system. Empirically, it is argued that the introduction of a marketing channel network has a positive influence on the financial value of the teams' business‐to‐business market but does not result in a change in the business demographics of corporate sponsors.

Research limitations

The study has possible sport‐specific limitations.

Practical implications

Business‐to‐business marketers and sport league managers should pay attention to the characteristics of the sport league as these influence the teams' business‐to‐business market. This is especially valid for sports in which teams rely strongly on sport sponsoring and, to a lesser extend, on gate revenues, television rights and prize money.

Originality/value

For the first time, this study examines and provides data on the business‐to‐business environment of teams in professional road cycling. It contributes to the literature of international sport marketing and professional road cycling, a sport gaining momentum in various countries and which is understudied in comparison to other sports.
The influence of culture and market orientation on services brands: insights from Irish banking and retail firms
Authors: Wallace Elaine , de Chernatony Leslie
Published: October 2011

Purpose

This paper aims to examine the influence of the culture of the service firm on its interpretation of the role of the brand and on the development and implementation of its brand values.

Design/methodology/approach

A grounded theory approach was used. Interviews were conducted with 20 managers within two leading banking firms in Ireland and two leading grocery retailers in Ireland.

Findings

The development of the brand, and its role within the firm, is closely related to the firm's culture. The research shows obstacles and opportunities created by the cultural context of firms wishing to disseminate and embed a set of brand values. The paper presents an “involvement model” of brand values implementation and outlines changes required to implement brand values.

Research limitations/implications

The study was bound by access to firms, and managers' availability. The authors sought an insight into the relationship between each firm's culture and its brands. They advocate quantitative research to further investigate the findings within these service sectors and to test proposed antecedents (transformational leadership, employee involvement) and outcomes (employee‐based brand equity and consumer‐based brand equity) of values adoption.

Practical implications

The paper identifies aspects of retail and banking cultures which support or detract from brand development. In particular, it presents the learnings from successful brand values implementation in a clan culture, aspects of which are applicable across other cultures.

Originality/value

The paper provides valuable insights into the role of the brand within the service firm and the positive and negative influence of context on brand values and their development and implementation.
Modeling service friendship and customer compliance in high‐contact service relationships
Authors: Lin Jiun‐Sheng Chris , Hsieh Chia‐Chuan
Published: October 2011

Purpose

The success of many high‐contact services depends on customers' compliance with providers' instructions. While existing service marketing literature urges increased attention to customer compliance, there is, to date, little research investigating its role of compliance in service settings. Based on social cognitive theory, this study aims to fill this important research gap, developing and testing a model to explore the antecedents and consequences of customer compliance in high‐contact service settings. Service friendship is included as a mediator between the antecedents and compliance. Two control variables, relationship duration and contact frequency, were also included in the model.

Design/methodology/approach

A research framework is proposed to suggest the antecedents and consequences of both service friendship and customer compliance. Extant research from various research streams is reviewed, deriving 11 hypotheses. Data collected from customers of high‐contact service industries are examined through structural equation modeling.

Findings

Results show that the service provider's social skills, customer orientation, and expertise are positively related to service friendship and customer compliance, which in turn affect customer satisfaction and anticipated future interaction. The control variables are also both positively associated with service friendship and anticipated future interaction.

Research limitations/implications

This research represents an early attempt at explaining what affects customer compliance in high‐contact service settings. Future research directions are discussed, with emphasis on incorporating customer characteristics, service interaction characteristics, and employee viewpoints to better understand service friendship and compliance in different service settings.

Practical implications

Customer compliance is a vital component of high‐contact service interactions between employees and customers. Service managers should encourage the formation of customer compliance in conjunction with service friendship to achieve better service outcomes.

Originality/value

This study represents the first study in the service marketing literature to establish a model that explains the mechanism of customer compliance in general service settings. The addition of two control variables representing relationship quantity also enhances the originality and contribution of this study.
Primary product network size on complementary product sales
Authors: Mai Enping (Shirley) , Yang Jun , Chen Haozhe
Published: October 2011

Purpose

The purpose of this paper is to examine the relationship between primary product network size and the sales of complementary products, and to suggest customer characteristics moderating this relationship.

Design/methodology/approach

A panel dataset in the online video game industry was used to verify the proposed theoretical framework. Two‐level hierarchical linear modeling is used to test several hypotheses.

Findings

The authors' analysis results suggest there is a positive relationship between the primary product network size and the sales of complementary products. Also, two customer characteristics (previous transaction value and customer purchase frequency) were found to positively influence the complementary product sales. The primary product's network size has a stronger impact on complementary product sales for light buyers compared to heavy buyers.

Research limitations/implications

This study only focused on online video industry, and the price differentiation of the products might not be adequately significant. Other relevant factors (such as word‐of‐mouth (WOM)) or other customer characteristics could also be relevant to complementary product sales. Therefore, future research could use data triangulation to collect data in different contexts, through a longer period of time, to test and verify the proposed relationships.

Practical implications

Product managers need to better understand the relationship between the primary product network size and the complementary product sales. They should adjust the marketing strategies toward different customer purchase frequency segments correspondingly. For example, to benefit further from the primary product network size, complementary product retailers can create online forums for all primary product users to influence light complementary product buyers.

Originality/value

This research is one of the first empirical investigations of establishing the relationship between primary product network size and complementary product sales, with customer characteristics as moderators.