bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous measurement of all thermoelectric properties of bulk materials in the temperature range 300–600 K
Authors: Kolb H. , Dasgupta T. , Zabrocki K. , Mueller E. , de Boor J.
Published: July 2015

Thermoelectric materials can directly convert heat into electrical energy. The characterization of different materials is an important part in thermoelectric materials research to improve their properties. Usually, different methods and setups are combined for the temperature dependent determination of all thermoelectric key quantities — Seebeck coefficient, electrical conductivity, and thermal conductivity. Here, we present a measurement system for the simultaneous determination of all of these quantities plus the direct determination of the figure of merit by means of the Harman method zTH in a temperature range from room temperature up to 600 K. A simultaneous measurement saves time and reduces the measurement error, and the change of all material properties can be monitored even for unstable materials. Thermal conductivity measurements are inherently affected by undesired thermal losses, in particular, through radiation at higher temperatures. We show a simple experimental approach to measure radiation losses and correct for those. Comparative measurements on traditional systems show good agreement for all measured quantities.
Implicit versus explicit momentum relaxation time solution for semiconductor nanowires
Authors: Marin E. G. , Ruiz F. G. , Godoy A. , Tienda-Luna I. M. , Gámiz F.
Published: July 2015

We discuss the necessity of the exact implicit Momentum Relaxation Time (MRT) solution of the Boltzmann transport equation in order to achieve reliable carrier mobility results in semiconductor nanowires. Firstly, the implicit solution for a 1D electron gas with a isotropic bandstructure is presented resulting in the formulation of a simple matrix system. Using this solution as a reference, the explicit approach is demonstrated to be inaccurate for the calculation of inelastic anisotropic mechanisms such as polar optical phonons, characteristic of III-V materials. Its validity for elastic and isotropic mechanisms is also evaluated. Finally, the implications of the MRT explicit approach inaccuracies on the total mobility of Si and III-V NWs are studied.
A self-consistent model for the saturation dynamics of the vortex shedding around the mean flow in the unstable cylinder wake
Authors: Mantič-Lugo Vladislav , Arratia Cristóbal , Gallaire François
Published: July 2015

The supercritical instability leading to the Bénard-von Karman vortex street in a cylinder wake is a well known example of supercritical Hopf bifurcation: the steady solution becomes linearly unstable and saturates into a periodic limit cycle. Nonetheless, a simplified physical formulation accurately predicting the transition dynamics of the saturation process is lacking. Building upon our previous work, we present here a simple self-consistent model that provides a clear description of the saturation mechanism in a quasi-steady manner by means of coupling the instantaneous mean flow with its most unstable eigenmode and its instantaneous amplitude through the Reynolds stress. The system is coupled for different oscillation amplitudes, providing an instantaneous mean flow as function of an equivalent time. A transient physical picture is described, wherein a harmonic perturbation grows and changes in amplitude, frequency, and structure due to the modification of the mean flow by the Reynolds stress forcing, saturating when the flow is marginally stable. Comparisons with direct numerical simulations show an accurate prediction of the instantaneous amplitude, frequency, and growth rate, as well as the saturated mean flow, the oscillation amplitude, frequency, and the resulting mean Reynolds stresses.
Ion-dust streaming instability with non-Maxwellian ions
Authors: Kählert Hanno
Published: July 2015

The influence of non-Maxwellian ions on the ion-dust streaming instability in a complex plasma is investigated. The ion susceptibility employed for the calculations self-consistently accounts for the acceleration of the ions by a homogeneous background electric field and their collisions with neutral gas particles via a Bhatnagar-Gross-Krook collision term [e.g., A. V. Ivlev et al., Phys. Rev. E 71, 016405 (2005)], leading to significant deviations from a shifted Maxwellian distribution. The dispersion relation and the properties of the most unstable mode are studied in detail and compared with the Maxwellian case. The largest deviations occur at low to intermediate ion-neutral damping. In particular, the growth rate of the instability for ion streaming below the Bohm speed is found to be lower than in the case of Maxwellian ions, yet remains on a significant level even for fast ion flows above the Bohm speed.
Linear magnetoresistance in three-dimensional carbon nanostructure with periodic spherical voids
Authors: Wang Leizhi , Yin Ming , Abdi Mohammed , Datta Timir
Published: July 2015

We report electrical transport properties of carbon nanostructures with close-packed spherical voids. Under zero magnetic field, a non-metallic behavior is observed. With increasing magnetic field, magnetoresistance (MR) crosses over from quadratic to linear dependence. Longitudinal response, typically negligible in most materials, exhibits the same value and field-temperature dependence as transverse MR. At intermediate angles (0°–90°) MR is also found to be independent of the direction of magnetic field. It is reasoned that orientation-insensitive, linear MR is due to distorted current flow in the 3-dimensional porous structures of this system.
Dipolar resonances in conductive carbon micro-fibers probed by near-field terahertz spectroscopy
Authors: Khromova I. , Navarro-Cía M. , Brener I. , Reno J. L. , Ponomarev A. , Mitrofanov O.
Published: July 2015

We observe dipole resonances in thin conductive carbon micro-fibers by detecting an enhanced electric field in the near-field of a single fiber at terahertz (THz) frequencies. Time-domain analysis of the electric field shows that each fiber sustains resonant current oscillations at the frequency defined by the fiber's length. Strong dependence of the observed resonance frequency and degree of field enhancement on the fibers' conductive properties enable direct non-contact probing of the THz conductivity in single carbon micro-fibers. We find the conductivity of the fibers to be within the range of 1–5×104 S/m. This approach is suitable for experimental characterization of individual doped semiconductor resonators for THz metamaterials and devices.
Chemical reactivity of twin-modified copper nanowire surfaces
Authors: Huang Chun-Lung , Liao Chien-Neng
Published: July 2015

Effect of twin boundary (TB) spacing on atomic surface structure and chemical reactivity of nanotwinned Cu nanowires (NWs) is investigated. Post-etching surface structure and wire diameter of Cu NWs were examined by transmission electron microscopy. When TB spacing is less than 10 nm, the Cu NWs remain almost intact after chemical attack and show faceted surface structures with low atomic step density. A mechanism based on surface tension torque acting on TB/surface triple junctions is proposed to explain the faceted structure formation and enhanced corrosion resistance of nanotwinned Cu NWs.
The disorder-induced Raman scattering in Au/MoS2 heterostructures
Authors: Gołasa K. , Grzeszczyk M. , Binder J. , Bożek R. , Wysmołek A. , Babiński A.
Published: July 2015

The Raman scattering has been studied in heterostructures composed of a thin MoS2 flake and a 1-1.5 nm layer of thermally evaporated gold (Au). There have been Au nanoislands detected in the heterostructure. It has been found that their surface density and the average size depend on the MoS2 thickness. The Raman scattering spectrum in the heterostructure with a few monolayer MoS2 only weakly depends on the excitation (resonant vs. non-resonant) mode. The overall Raman spectrum corresponds to the total density of phonon states, which is characteristic for disordered systems. The disorder in the MoS2 layer is related to the mechanical strain induced in the MoS2 layer by the Au nanoislands. The strain results in the localization of phonon modes, which leads to the relaxation of the momentum conservation rule in the scattering process. The relaxation allows phonons from the whole MoS2 Brillouin zone to interact with electronic excitations. Our results show that the Au nanoislands resulted from thermal evaporation of a thin metal layer introduce substantial disorder into the crystalline structure of the thin MoS2 layers.
Tunable photoluminescence from sheet-like black phosphorus crystal by electrochemical oxidation
Authors: Gan Z. X. , Sun L. L. , Wu X. L. , Meng M. , Shen J. C. , Chu Paul K.
Published: July 2015

An electrochemical method to prepare two-dimensional (2D) layered black phosphorus oxide with an inhomogeneous and non-stoichiometric structure is developed and described. The localized oxygen-related electronic states induce tunable photoluminescence (PL) between 620 and 670 nm. After oxidation, several new Raman modes with frequencies below 300 cm−1 emerge and the Ag1 mode splits into two sub-bands. The frequency difference between the two sub-bands (Δ) exhibits a monotonic dependence on the emission wavelength suggesting that PL is determined by the degree of oxidation. Similar to graphene oxide, phosphorene oxide is a promising 2D structure with many potential applications.
Cube-like Cu2MoS4 photocatalysts for visible light-driven degradation of methyl orange
Authors: Zhang Ke , Chen Wenxing , Wang Yu , Li Jiong , Chen Haiping , Gong Zhiyu , Chang Shuo , Ye Fei , Wang Tianxing , Chu Wangsheng , Zou Chongwen , Song Li
Published: July 2015

Cube-like Cu2MoS4 nanoparticles with low-index facets and high crystallinity were fabricated via a hydrothermal method. The as-obtained nanocubes with an average size of 40-60 nm are composed of stacking-Cu2MoS4 layers separated by a weak Van der Waals gap of 0.5 nm. A strong absorption at visible light region is observed in the nanocube aqueous solution, indicating its optical-band gap of 1.78 eV. The photocatalytic measurements reveal that the nanocubes can thoroughly induce the degradation of methyl orange under visible light irradiation with good structural stability. Our finding may provide a way in design and fabrication of transition metal dichalcogenide nanostructures for practical applications.
Drill-cored rock pools: an effective method of ecological enhancement on artificial structures
Authors: Evans Ally J. , Firth Louise B. , Hawkins Stephen J. , Morris Elisabeth S. , Goudge Harry , Moore Pippa J.
Published: July 2015

Coastal defences are proliferating in response to anticipated climate change and there is increasing need for ecologically sensitive design in their construction. Typically, these structures support lower biodiversity than natural rocky shores. Although several studies have tested habitat enhancement interventions that incorporate novel water-retaining features into coastal defences, there remains a need for additional long-term, fully replicated trials to identify alternative cost-effective designs. We created artificial rock pools of two depths (12cm, 5cm) by drill-coring into a shore-parallel intertidal granite breakwater, to investigate their potential as an intervention for delivering ecological enhancement. After 18 months the artificial rock pools supported greater species richness than adjacent granite rock surfaces on the breakwater, and similar species richness to natural rock pools on nearby rocky shores. Community composition was, however, different between artificial and natural pools. The depth of artificial rock pools did not affect richness or community structure. Although the novel habitats did not support the same communities as natural rock pools, they clearly provided important habitat for several species that were otherwise absent at mid-shore height on the breakwater. These findings reveal the potential of drill-cored rock pools as an affordable and easily replicated means of enhancing biodiversity on a variety of coastal defence structures, both at the design stage and retrospectively.
Influence of Smallmouth Bass Predation on Recruitment of Age-0 Yellow Perch in South Dakota Glacial Lakes
Authors: Dembkowski Daniel J. , Willis D. W. , Blackwell B. G. , Chipps S. R. , Bacula T. D. , Wuellner M. R.
Published: July 2015

We estimated the influence of predation by Smallmouth Bass Micropterus dolomieu on recruitment of age-0 Yellow Perch Perca flavescens in two northeastern South Dakota glacial lakes. We estimated a likely range in consumption of age-0 Yellow Perch using Smallmouth Bass diet information from two time periods when age-0 Yellow Perch constituted high (2008) and low (2012 and 2013) proportions of Smallmouth Bass diets, and bass population size estimates as inputs in a bioenergetics model. The proportion of age-0 Yellow Perch consumed by the Smallmouth Bass populations was determined by comparing estimates of consumption with estimates of age-0 perch production. During 2008, age-0 Yellow Perch constituted between 0% and 42% of Smallmouth Bass diets by weight, whereas during 2012 and 2013, age-0 perch constituted between 0% and 20% of bass diets by weight. Across both lakes and time periods, production of age-0 Yellow Perch ranged from 0.32 to 1.78 kg·ha−1·week−1. Estimates of Smallmouth Bass consumption measured during the same intervals ranged from 0.06 to 0.33 kg·ha−1·week−1, equating to consumption of between 1% and 34% of the available Yellow Perch biomass. Given current conditions relative to Smallmouth Bass abundance and consumption dynamics and production of age-0 Yellow Perch, it does not appear that Smallmouth Bass predation acts as a singular factor limiting recruitment of age-0 Yellow Perch in our study lakes. However, future research and management initiatives should recognize that the long-term impact of Smallmouth Bass predation is not static and will likely fluctuate depending on environmental (e.g., temperature) and biotic (e.g., trends in macrophyte abundance, predator and prey population structure and abundance, and predatory fish assemblage dynamics) characteristics.

Received December 19, 2014; accepted April 20, 2015
University–industry linkages in the UK: emerging themes and ‘unanswered’ questions
Authors: Gilman Mark , Serbanica Cristina
Published: July 2015

With university–industry engagement forming an integral part of the policy agenda, this paper underlines current issues and emerging themes in the dedicated literature. It utilises a comprehensive literature review, based on evidence from peer-reviewed journals/public reports published after 2005 in the UK. The paper integrates a wide range of disparate studies on university–industry knowledge transfer patterns, determinants and impacts, and offers a panorama that could be useful to inform on the variety of issues underlying knowledge transfer. Given the importance/complexity of university–industry interactions, a comprehensive study fills an existing gap. Second, due to its focus on current issues, the study opens the way to reflections and debates on critically ‘unanswered’ questions: how to deal with diversity/heterogeneity? How to increase quality in supply/quantity in demand for knowledge? How to increase impact on academics, universities, firms, economy and society?
Contemplation of Smoking Cessation and Quit Attempts in Human Immunodeficiency Virus–Infected and Uninfected Veterans
Authors: Shahrir Shahida , Tindle Hilary A. , McGinnis Kathleen A. , Fiellin David A. , Goulet Joseph , Akgün Kathleen M. , Gibert Cynthia L. , Rodriguez-Barradas Maria C. , Crothers Kristina
Published: July 2015

Background

As antiretroviral treatments prolong life in human immunodeficiency virus (HIV)-infected patients, smoking cessation is now a top priority. However, studies of HIV-infected smokers have not been conducted with uninfected controls. In this study, researchers determined factors associated with contemplating smoking cessation and making a prior quit attempt among HIV-infected and uninfected smoking veterans.

Methods

Between 2005 and 2007, 1,027 HIV-infected and 794 uninfected smokers were identified as part of the Veterans Aging Cohort Study (VACS). Stratifying by HIV status, adjusted odds ratios (AORs) were calculated using logistic regression to identify factors associated with contemplating smoking cessation and making a prior quit attempt.

Results

Most participants (66 % of HIV-infected vs. 68 % of uninfected; P = .46) were contemplating cessation, and 56 % of both groups ( P = .99) had attempted to quit in the last year. In stratified multivariable analyses, HIV-infected smokers with recent pulmonary disease diagnoses were more likely to have made a quit attempt (AOR = 4.93, 95 % confidence interval [CI] = 1.41–17.17). Both HIV-infected and uninfected patients with unhealthy alcohol use were less likely to be contemplating cessation (AOR = 0.66, 95 % CI = 0.49–0.90 and 0.71, 95 % CI = 0.50–1.00). HIV-infected smokers who reported unhealthy alcohol use were also less likely to have made a quit attempt in the last year (AOR = 0.68, 95 % CI = 0.51–0.91).

Conclusions

Patient-level interest and motivation are not major barriers to smoking cessation among HIV-infected veterans. Targeting HIV-infected smokers with a recent pulmonary disease diagnosis may improve sustained smoking cessation. Unhealthy alcohol use appears to be a key modifiable risk factor. Smoking cessation rates may be improved by combining interventions for smoking and alcohol use for HIV-infected patients.
Candida biomarkers in patients with candidaemia and bacteraemia
Authors: Martínez-Jiménez M. Carmen , Muñoz Patricia , Valerio Maricela , Alonso Roberto , Martos Carmen , Guinea Jesús , Bouza Emilio
Published: July 2015

Objectives

Microbiological strategies are necessary to help clinicians discontinue empirical antifungal therapy in patients with suspected invasive candidiasis. Culture methods and biomarkers each show low sensitivity. We analysed the value of combining different biomarkers as a decision-making tool for discontinuing empirical antifungal treatment.

Methods

We studied stored serum samples from 31 patients with candidaemia (Candida albicans 40%, Candida tropicalis 20%, Candida parapsilosis 18%, Candida glabrata 12% and other 10%) and 50 patients with bacteraemia at Gregorio Marañón Hospital, Madrid, Spain. C. albicans germ tube antibody (CAGTA), mannan antigens (MN), antimannan antibodies (AMN) and (1→3)-β-d-glucan (BDG) were assayed using the manufacturer's and alternative cut-offs to improve the accuracy of the tests.

Results

The sensitivity of the biomarkers when used alone was low (58%−84%), but specificity was high (65.8%−92.0%). The best combinations were CAGTA and BDG using cut-offs of 1/80 and 80 pg/mL, respectively (sensitivity 96.8% and specificity 84%), and CAGTA and MN using cut-offs of 1/80 and 75 pg/mL, respectively (sensitivity 93.5% and specificity 86.0%). The sensitivity of both combinations was 100% for C. albicans, C. tropicalis and C. parapsilosis, but only combinations including BDG detected Candida krusei. The negative predictive values (NPVs) of both combinations were, respectively, 97.7% and 95.6% (prevalence of candidaemia, 23.6%). For a prevalence of candidaemia of 5% and 10%, the NPV reached 99.8% and 99.6%.

Conclusions

The combinations of CAGTA and BDG or CAGTA and MN had a very high NPV at the alternative cut-offs and could be used in antifungal stewardship programmes as a decision-making tool for discontinuing unnecessary empirical therapy in patients with suspected candidaemia.
Activity of ceftazidime/avibactam against isogenic strains of Escherichia coli containing KPC and SHV β-lactamases with single amino acid substitutions in the Ω-loop
Authors: Winkler Marisa L. , Papp-Wallace Krisztina M. , Bonomo Robert A.
Published: July 2015

Objectives

The objective of this study was to explore the activity of ceftazidime and ceftazidime/avibactam against a collection of isogenic strains of Escherichia coli DH10B possessing SHV and KPC β-lactamases containing single amino acid substitutions in the Ω-loop (residues 164–179).

Methods

Ceftazidime and ceftazidime/avibactam MICs were determined by the agar dilution method for a panel of isogenic E. coli strains expressing SHV-1 and KPC-2 with amino acid substitutions at positions 164, 167, 169 or 179. Two KPC-2 β-lactamase variants that possessed elevated MICs of ceftazidime/avibactam were selected for further biochemical analyses.

Results

Avibactam restored susceptibility to ceftazidime for all Ω-loop variants of SHV-1 with MICs <8 mg/L. In contrast, several of the Arg164 and Asp179 variants of KPC-2 demonstrated MICs of ceftazidime/avibactam >8 mg/L. β-Lactamase kinetics showed that the Asp179Asn variant of KPC-2 demonstrated enhanced kinetic properties against ceftazidime. The Ki app, k2/K and koff of the Arg164Ala and Asp179Asn variant KPC-2 β-lactamases indicated that avibactam effectively inhibited these enzymes.

Conclusions

Several KPC-2 variants demonstrating ceftazidime resistance as a result of single amino acid substitutions in the Ω-loop were not susceptible to ceftazidime/avibactam (MICs >8 mg/L). We hypothesize that this observation is due to the stabilizing interactions (e.g. hydrogen bonds) of ceftazidime within the active site of variant β-lactamases that prevent avibactam from binding to and inhibiting the β-lactamase. As ceftazidime/avibactam is introduced into the clinic, monitoring for new KPC-2 variants that may exhibit increased ceftazidime kinetics as well as resistance to this novel antibiotic combination will be important.
Within-host diversity of MRSA antimicrobial resistances
Authors: Stanczak-Mrozek Kinga I. , Manne Anusha , Knight Gwenan M. , Gould Katherine , Witney Adam A. , Lindsay Jodi A.
Published: July 2015

Objectives

MRSA is a major antimicrobial resistance (AMR) pathogen. The reservoir of infecting isolates is colonization, which is the site of evolutionary selection. The aim was to identify if AMRs in colonizing MRSA populations diversified and potential mechanisms of resistance gene transfer in vivo.

Methods

Nasal swabs from 38 MRSA carriers admitted to hospital were plated and 20 individual colonies from each patient tested for phenotypic antibiotic susceptibility and genetically for lineage, carriage of four prophages and three plasmid families. Free bacteriophages were detected in swabs as well as their capacity for transducing resistance genes.

Results

Nine (24%) patients carried phenotypic AMR variants and 24 (63%) carried prophage and plasmid variants. If a single colony was selected for testing, the probability of detecting all AMR in that patient was 87%. Sixty-four different AMR and mobile genetic element (MGE) profiles were detected, mostly in the MRSA CC22 background (where CC stands for clonal complex), with up to 8 profiles per patient. Nearly half of the patients carried detectable free bacteriophages and phages successfully transduced resistance genes between laboratory and patient isolates in vitro. WGS showed MRSA core genomes were stable, while AMR and MGEs varied.

Conclusions

‘Clouds’ of MRSA variants that have acquired or lost AMR and MGEs are common in nasal colonizing populations and bacteriophages may play an important role in gene transfer. Accurate estimation of AMR and genetic variability has implications for diagnostics, epidemiology, antimicrobial stewardship and understanding the evolutionary selection of AMR in colonizing populations.
Functional Properties of Submicron‐Scale Rice Flour Produced by Wet Media Grinding
Authors: Hossen Md. Sharif , Sotome Itaru , Nanayama Kazuko , Sasaki Tomoko , Okadome Hiroshi
Published: July 2015

The digestibility and hydration properties of wet‐ground submicron‐scale rice flour were compared with those of dry‐ground coarser microscale flours. The submicron flour (mean size 0.6 µm) was produced in a wet‐media mill with 0.3 mm zirconia beads by continuous 24 h pulverization. The solubility, water absorption index, and swelling power increased as the mean particle size decreased, reaching maximum values in the submicron flour. Starch damage was high in the submicron flour, with the absence of intact starch granules. The digestibility also increased as the particle size decreased, and it was highest in the submicron flour. These results show that wet‐ground submicron rice flour has different functional properties from dry‐ground coarser flour. The digestibility was more strongly influenced by starch damage and the water absorption index than by the mean particle size.
Virulence, Host-Selective Toxin Production, and Development of Three Cochliobolus Phytopathogens Lacking the Sfp-Type 4′-Phosphopantetheinyl Transferase Ppt1
Authors: Zainudin Nur Ain Izzati Mohd , Condon Bradford , De Bruyne Lieselotte , Van Poucke Christof , Bi Qing , Li Wei , Höfte Monica , Turgeon B. Gillian
Published: July 2015

The Sfp-type 4′-phosphopantetheinyl transferase Ppt1 is required for activation of nonribosomal peptide synthetases, including α-aminoadipate reductase (AAR) for lysine biosynthesis and polyketide synthases, enzymes that biosynthesize peptide and polyketide secondary metabolites, respectively. Deletion of the PPT1 gene, from the maize pathogen Cochliobolus heterostrophus and the rice pathogen Cochliobolus miyabeanus, yielded strains that were significantly reduced in virulence to their hosts. In addition, ppt1 mutants of C. heterostrophus race T and Cochliobolus victoriae were unable to biosynthesize the host-selective toxins (HST) T-toxin and victorin, respectively, as judged by bioassays. Interestingly, ppt1 mutants of C. miyabeanus were shown to produce tenfold higher levels of the sesterterpene-type non-HST ophiobolin A, as compared with the wild-type strain. The ppt1 strains of all species were also reduced in tolerance to oxidative stress and iron depletion; both phenotypes are associated with inability to produce extracellular siderophores biosynthesized by the nonribosomal peptide synthetase Nps6. Colony surfaces were hydrophilic, a trait previously associated with absence of C. heterostrophus Nps4. Mutants were decreased in asexual sporulation and C. heterostrophus strains were female-sterile in sexual crosses; the latter phenotype was observed previously with mutants lacking Nps2, which produces an intracellular siderophore. As expected, mutants were albino, since they cannot produce the polyketide melanin and were auxotrophic for lysine because they lack an AAR.
Quantifying the Effects of Wheat Residue on Severity of Stagonospora nodorum Blotch and Yield in Winter Wheat
Authors: Mehra L. K. , Cowger C. , Weisz R. , Ojiambo P. S.
Published: July 2015

Stagonospora nodorum blotch (SNB), caused by the fungus Parastagonospora nodorum, is a major disease of wheat (Triticum aestivum). Residue from a previously infected wheat crop can be an important source of initial inoculum, but the effects of infected residue on disease severity and yield have not previously been quantified. Experiments were conducted in Raleigh and Salisbury, North Carolina, in 2012, 2013, and 2014 using the moderately susceptible winter wheat cultivar DG Shirley. In 2014, the highly susceptible cultivar DG 9012 was added to the experiment and the study was conducted at an additional site in Tyner, North Carolina. Four (2012) or six (2013 and 2014) wheat residue treatments were applied in the field in a randomized complete block design with five replicates. Treatments in 2012 were 0, 30, 60, and 90% residue coverage of the soil surface, while 10 and 20% residue treatments were added in 2013 and 2014. Across site-years, disease severity ranged from 0 to 50% and increased nonlinearly (P < 0.05) as residue level increased, with a rapid rise to an upper limit and showing little change in severity above 20 to 30% soil surface coverage. Residue coverage had a significant (P < 0.05) effect on disease severity in all site-years. The effect of residue coverage on yield was only significant (P < 0.05) for DG Shirley at Raleigh and Salisbury in 2012 and for DG 9012 at Salisbury in 2014. Similarly, residue coverage significantly (P < 0.05) affected thousand-kernel weight only of DG 9012 in 2014 at Raleigh and Salisbury. Our results showed that when wheat residue was sparse, small additions to residue density produced greater increases in SNB than when residue was abundant. SNB only led to effects on yield and test weight in the most disease-conducive environments, suggesting that the economic threshold for the disease may be higher than previously assumed and warrants review.
Maize pan-transcriptome provides novel insights into genome complexity and quantitative trait variation
Authors: Jin Minliang , Liu Haijun , He Cheng , Fu Junjie , Xiao Yingjie , Wang Yuebin , Xie Weibo , Wang Guoying , Yan Jianbing
Published: July 2015

Variation in gene expression contributes to the diversity of phenotype. The construction of the pan-transcriptome is especially necessary for species with complex genomes, such as maize. However, knowledge of the regulation mechanisms and functional consequences of the pan-transcriptome is limited. In this study, we identified 13,382 nuclear expression presence and absence variation candidates (ePAVs, expressed in 5%~95% lines; based on the reference genome) by re-analyzing the RNA sequencing data from the kernels (15 days after pollination) of 368 maize diverse inbreds. It was estimated that only ~1% of the ePAVs are explained by DNA sequence presence and absence variations (PAV). The ePAV genes tend to be regulated by distant eQTLs when compared with non-ePAV genes (called here core expression genes, expressed in more than 95% lines). When the expression presence/absence status was used as the “ genotype” to perform genome-wide association study, 56 (0.42%) ePAVs were significantly associated with 15 agronomic traits and 1,967 (14.74%) with 526 metabolic traits, measured from the mature kernels. While the above was majorly based on the reference genome, by using a modified ‘assemble-then-align’ strategy, 2,355 high confidence novel sequences with a total length of 1.9Mb were found absent in the current B73 reference genome (v2). Ten randomly selected novel sequences were validated with genomic PCR. A simulation analysis suggested that the pan-transcriptome of the maize whole kernel is approaching a maximum value of 63,000 genes. Two novel validated sequences annotated as NBS_LRR like genes were found to associate with flavonoid content and their homologs in rice were also found to affect flavonoids and disease-resistance. Novel sequences absent in the present reference genome might be functionally important and deserve more attentions. This study provides novel perspectives and resources to discover maize quantitative trait variations and help us to better understand the kernel regulation networks, thus enhancing maize breeding.
Haplotypes of common SNPs can explain missing heritability of complex diseases
Authors: Bhatia Gaurav , Gusev Alexander , Loh Po-Ru , Vilhjálmsson Bjarni J. , Ripke Stephan ,   Schizophrenia Working Group of the Psychiatric Genomics Consortium, Purcell Shaun , Stahl Eli , Daly Mark , Candia Teresa R de , Kendler Kenneth S. , O’Donovan Michael C , Lee Sang Hong , Wray Naomi R. , Neale Benjamin M , Keller Matthew C. , Zaitlen Noah A. , Pasaniuc Bogdan , Yang Jian , Price Alkes L.
Published: July 2015

While genome-wide significant associations generally explain only a small proportion of the narrow-sense heritability of complex disease (h2), recent work has shown that more heritability is explained by all genotyped SNPs (hg2). However, much of the heritability is still missing (hg2<h2). For example, for schizophrenia,h2is estimated at 0.7-0.8 buthg2is estimated at ∼0.3. Efforts at increasing coverage through accurately imputed variants have yielded only small increases in the heritability explained, and poorly imputed variants can lead to assay artifacts for case-control traits. We propose to estimate the heritability explained by a set of haplotype variants (haploSNPs) constructed directly from the study sample (hhap2). Our method constructs a set of haplotypes from phased genotypes by extending shared haplotypes subject to the 4-gamete test. In a large schizophrenia data set (PGC2-SCZ), haploSNPs with MAF > 0.1% explained substantially more phenotypic variance (hhap2= 0.64 (S.E. 0.084)) than genotyped SNPs alone (hg2= 0.32 (S.E. 0.029)). These estimates were based on cross-cohort comparisons, ensuring that cohort-specific assay artifacts did not contribute to our estimates. In a large multiple sclerosis data set (WTCCC2-MS), we observed an even larger difference betweenhhap2andhg2, though data from other cohorts will be required to validate this result. Overall, our results suggest that haplotypes of common SNPs can explain a large fraction of missing heritability of complex disease, shedding light on genetic architecture and informing disease mapping strategies.
A novel imaging tool for hepatic portal system using phase contrast technique with hydrogen peroxide-generated O2gas
Authors: Tang Rongbiao , Yan Fuhua , Chai Wei-Min , Huang Wei , Fu Yanan , Yang Guo-Yuan , Chen Ke-Min
Published: July 2015

The objective of this study was to investigate the potential of hydrogen peroxide-generated oxygen gas-based phase contrast imaging (PCI) for visualizing mouse hepatic portal veins. The O2gas was made from the reaction between H2O2and catalase. The gas production was imaged by PCI in real time. The H2O2was injected into the enteric cavity of the lower sigmoid colon to produce O2in the submucosal venous plexus. The generated O2gas could be finally drained into hepatic portal veins. Absorption contrast imaging (ACI) and PCI of O2-filled portal veins were performed and compared. PCI offers high resolution and real-time visualization of the O2gas production. Compared with O2-based ACI, O2-based PCI significantly enhanced the revealing of the portal veinin vivo. It is concluded that O2-based PCI is a novel and promising imaging modality for future studies of portal venous disorders in mice models.
A soft X-ray plane-grating monochromator optimized for elliptical dipole radiation from modern sources
Authors: Kachel Torsten , Eggenstein Frank , Follath Rolf
Published: July 2015

A new but yet well proven way of making elliptically polarized dipole radiation from the BESSY II storage ring applicable to the SX700-type collimated plane-grating monochromator PM3 is described. It is shown that due to the limited vertical acceptance of the grating a simple use of vertical apertures is not possible in this case. Rather, deflecting the beam upwards or downwards by rotating the vertically collimating toroidal mirror M1 around the light axis leads to excellent performance. The resulting detuning of the photon energy can be taken into account by a readjustment of the monochromator internal plane mirror M2. The energy resolution of the beamline is not affected by the non-zero `roll' of the collimating mirror.
How strategy changes in different monetary policy conditions
Authors: Yang Yan , Wang Fengli , Chen Shou
Published: July 2015

Purpose

– The paper aims to address how firms make strategic adjustment to the changing resource availability in different monetary policy conditions and how the stickiness of cost influences the strategic adjustment, and to dig out the major internal and industrial factors that influence the relationship between strategic change and monetary policy conditions.

Design/methodology/approach

– The mechanism of how monetary policy affects strategic change is expounded by resource-based view and transaction cost theory. The balanced panel data of 422 companies of manufacturing industry listed in Chinese A share market before the end of 2003 from 2004-2013 are selected as sample to test the theoretic hypotheses.

Findings

– It was found that looser monetary policy results in greater strategic change than the tighter one for the high adjustment cost. External capital dependence and industrial competition intensity strengthen the positive correlation between monetary policy condition and strategic change. Private firms are more susceptible to money supply condition change compared with state-owned enterprises. Companies tend to expand investment on fixed asset but to shrink investment on R & D and trademark in looser money supply condition.

Practical implications

– Companies make bigger strategic adjustment in looser monetary policy condition for the greater availability of financial resources and lower market risk, but smaller adjustment in the tight one. However, owing to the sunk cost and the high adjustment cost, companies are not suggested to make aggressive strategic adjustment in the loose monetary conditions so as to avoid overcapacity and financial risk in tight monetary policy condition. For the policy-maker, as loose monetary policy cannot stimulate innovation but boost expansion on capacity, it is better to strengthen the resources configuration mechanism of monetary policy when making monetary policy.

Originality/value

– This paper fulfils a theoretic gap to study the mechanism of how monetary policy influence corporate strategic resource reconfiguration via affecting the resource base of a company by combining resource-based view and transaction cost theory.
Mandatory and voluntary information disclosure and the effects on financial analysts
Authors: Wang Shengnian , Han Liang , Gao Weiting
Published: July 2015

Purpose

– This paper aims to make a comparison, different from existing literature solely focusing on voluntary earnings forecasts and ex post earnings surprise, between the effects of mandatory earnings surprise warnings and voluntary information disclosure issued by management teams on financial analysts in terms of the number of followings and the accuracy of earnings forecasts.

Design/methodology/approach

– This paper uses panel data analysis with fixed effects on data collected from Chinese public firms between 2006 and 2010. It uses an exogenous regulation enforcement to minimise the endogeneity problem.

Findings

– This paper finds that financial analysts are less likely to follow firms which mandatorily issue earnings surprise warnings ex ante than those voluntarily issue earnings forecasts. Moreover, ex post, they issue less accurate and more dispersed forecasts on former firms. The results support Brown et al.’s (2009) finding in the USA and suggest that the earnings surprise warnings affect information asymmetries.

Practical implications

– This paper justifies the mandatory earnings surprise warnings policy issued by Chinese Securities Regulatory Commission in 2006.

Originality/value

– Mandatory earnings surprise is a unique practical regulation for publicly listed firms in China. This paper, for the first time, provides empirical evaluation on the effectiveness of a mandatory information disclosure policy in China. Consistent with existing literature on information disclosure by public firms in other countries, this paper finds that, in China, voluntary information disclosure captures more private information than mandatory information disclosure on corporate earnings ability.
Dynamics between currency and equity in Chinese markets
Authors: Aftab Muhammad , Ahmad Rubi , Ismail Izlin
Published: July 2015

Purpose

– This study aims to examine the dynamics between exchange rate and equities contextualizing the current liberal currency regime in China. This investigation also extends the analysis to explore the potential important factors influencing the interactions between these two markets. After exchange rate reforms, currency issue has emerged as a new dimension in portfolio decisions and diversification strategies in Chinese equity markets.

Design/methodology/approach

– This research uses the dynamic conditional correlation generalized autoregressive conditional heteroskedasticity model proposed by Engle (2002) to explore the dynamic interactions between the currency and stock markets. Further, the paper uses regression analysis to explore the explanatory channels of the correlation. The sample comprises 1,265 listed companies over the period 2005-2012 with daily, weekly and monthly observations. To make analysis robust, the study also considers different exchange rates and equities belonging to different industries.

Findings

– The findings suggest that exchange rate and stock price are related negatively. This conduit increases during the financial crisis period. This association is more prominent at monthly frequency than that of daily and weekly frequencies, which may refer to the noise factor in the high-frequency data. For a portfolio diversification point of view, currency may be considered an alternative diversifier against equity in China. The results also suggest a weak influence of market forces on the association between the currency and stock markets.

Originality/value

– Much of the related past research is based on co-integration approaches and limited to the relationship between currency and equity markets without exploring the determining channels of this important connection. This study uses a more suitable approach to examine the topic and also investigates the determinants. Besides, previous studies take index data which may be poor to depict the overall market outlook. This paper proceeds with firm-level data which are more appropriate to expose the overall market outlook and investor behavior. This research also draws valuable implications.
Business strategy, market competition and earnings management
Authors: Wu Peng , Gao Lei , Gu Tingting
Published: July 2015

Purpose

– The purpose of this study is to explore the relationships among business strategy, market competition and earnings management.

Design/methodology/approach

– This paper uses 2,037 Chinese A-share listed firms from 2010 to 2012 to test the research questions using regression analyses.

Findings

– The firms that follow cost leadership strategy (cost leaders) are more likely to have a higher level of real earnings management. The firms that follow differentiation strategy (differentiators) are less likely to use real earnings management. For cost leaders, the market competition further increases the level of real earnings management, whereas the level of earnings management of differentiators is not significantly impacted by the market competition.

Practical implications

– Results of this study indicate the feasibility of differentiation strategy in China and suggest that management should be encouraged to use such a strategy or to use a hybrid strategy to achieve its operational and financial goals.

Originality/value

– The study contributes to the research of earning management by providing evidence on that business strategy has significant impacts on earnings management. It also shows an incremental influence of market competition on earnings management through its impacts on business strategy.
A sociological theory of corporate finance
Authors: Li Yuanhui , Foo Check Teck
Published: July 2015

Purpose

– The paper aims to investigate the relationship between social responsibility and equity in China. In the process, the authors utilize data on corporate social responsibility (CSR) reports (in particular, information disclosure) and equity capital (focusing on cost). The overarching hypothesis may be phrased simply as: is CSR reporting rewarded by the capital market in China?

Design/methodology/approach

– The data of 3,012 list corporations in China securities are used and 1,015 CSR report quality scores (Rankins CSR Ratings) are hand-gathered from HEXUN (Web site) and utilized in the process of developing the model; financial and stock market information is obtained from the Wind database and the China Stock Market and Accounting Research database.

Findings

– The authors’ results suggest that overall the quality of CSR report is strongly, negatively related with the cost of capital: the higher the quality of social responsibility information disclosure, the lower the cost of equity capital. Most intriguingly, the authors find a sharp contrast between the government-owned corporations (state-owned enterprises) and privately owned, listed corporations. The quality of CSR reporting has a much higher impact in lowering the cost of equity capital for privately owned corporations. In contrasting the results for mandatory versus voluntary CSR disclosure, the quality of CSR reporting for the latter does not have any higher impact in lowering the cost of equity.

Practical implications

– Good social responsibility behavior by corporations and their subsequent information disclosure has beneficial financial impacts. In the authors’ research, the authors showed its immediate impact to be in the lowering of the overall corporate cost of equity. In this regard, the authors would recommend that chief executive officers pay more attention to CSR practice and its disclosure. Private firms issuing CSR reports will benefit from much lower financing costs through the capital market.

Originality/value

– Due to the structure of capital markets in China, the authors are able to show that CSR reporting of privately owned, listed corporations have much more effective signaling power. On the basis of the authors’ empirical findings in relation to the quality of CSR reporting and its impact on cost of capital, the authors suggest there is greater scope for research which takes a “finance and society” perspective. Based on more extensive research, such a perspective may enable scholars to orientate finance and finance research toward a model of “socio-capitalism”.
“Passivity”: a model of grocery retail price decision-making practice
Authors: Watson Iain , Wood Steve , Fernie John
Published: July 2015

Purpose

– This paper aims to explore the applied context of grocery retail pricing practice to understand how pricing executives approach “regular price” decision-making (as opposed to promotional pricing). The study seeks to inductively develop a model of regular price decision-making in grocery retailing.

Design/methodology/approach

– The research uses an inductive methodology involving interviews with pricing executives working for grocery retailers that account for approximately 85 per cent of the UK, and 64 per cent of USA, grocery market retail sales. The approach is appropriate given the underdeveloped research insights into regular pricing within food retailers.

Findings

– It is found that regular pricing is undertaken with little sophistication, typically, on the basis of simple, inflexible rules that result in conflicting goals. A typology of three pricing roles was identified, although all share an underdeveloped understanding of the effects of price changes on customer demand and the implications of competitor reactions. These contexts, causes and conditions lead to a range of consequences; notably, a degree of pricing inertia, “customer-less” pricing and “enforced symbiosis” – coping outcomes. Taken together, a theory of “passivity” pricing is identified.

Originality/value

– The research presents a contribution to new knowledge in the field of retail marketing by developing theory in retail pricing. In contrast to much extant research on grocery pricing, this paper accesses the insights and opinions of the pricing executives themselves. It exposes the realities of regular price decision-making across two developed retail markets and offers managerial insights.