bluuebunny/crossref_metadata_2025 huggingface dataset:
Dual-mode characteristics of the Buneman instability in a bounded slab plasma
Authors: Hong Woo-Pyo , Jung Young-Dae
Published: June 2015

The dual-mode characteristics of the Buneman instability are investigated in a slab plasma, including the geometric effects. The dual symmetric and anti-symmetric dispersion modes of the Buneman instability are obtained by the plasma dielectric function with the spectral reflection conditions for the slab geometry. The result shows that the magnitudes of the growth rate for the symmetric mode are always greater than those for the anti-symmetric mode. It is also found that the geometric effect suppresses the position of the maximum growth rate for the Buneman instability in bounded slab plasmas since the maximum conditions for the symmetric and anti-symmetric modes of the Buneman instability are given by 0.60<kzv0/ωpe<0.65. The physical characteristics and properties of the dual modes of the Buneman instability are also discussed.
Radiation characteristics of femtosecond laser-induced plasma channel Vee antenna
Authors: Choe Yun-Sik , Hao Zuoqiang , Lin Jingquan
Published: June 2015

A virtual reconfigurable plasma Vee antenna consisting of a set of laser plasma filaments produced by femtosecond laser pulses in air is investigated in this paper. The calculation results show that radiation pattern becomes more complex and gain shows initially rapid rise but gradually saturate as the leg length increases, but the pattern and gain are not seriously affected by the plasma conductivity; particularly, the gain of the Vee antenna with plasma conductivity σ = 100S/m can reach about 80% of that of a copper antenna. Radiation efficiency of the antenna has shown a strong dependence on radius of the antenna leg, and an efficiency of 65%, considered to have a proper performance, can be obtained with the channel radius of about 10 mm. Apex angle variation can lead to significant change of the radiation pattern and influence the gain; the best apex angle corresponding to maximal gain and good directivity for the third resonance antenna leg length is found to be at 74° at 600 MHz and σ = 100 S/m. The calculation has shown that at terawatt laser power level, the plasma channel conductivity is close to that of conventional plasma antenna, and peak gain of the Vee antenna is more than 8 dB with a good directivity. In addition, the radiation pattern of special Vee antennas with apex angle 180°-dipole antennas, for first and third resonance leg lengths, is compared and underneath physics of the difference is given. The laser-induced plasma channel antenna is especially suitable for achieving good directivity and gain, which has advantage over conventional plasma antenna with gas discharge tube or metal antenna.
Influence of electron transport layer thickness on optical properties of organic light-emitting diodes
Authors: Liu Guohong , Liu Yong , Li Baojun , Zhou Xiang
Published: June 2015

We investigate experimentally and theoretically the influence of electron transport layer (ETL) thickness on properties of typical N,N′-diphenyl-N,N′-bis(1-naphthyl)-[1,1′-biphthyl]-4,4′-diamine (NPB)/tris-(8-hydroxyquinoline) aluminum (Alq3) heterojunction based organic light-emitting diodes (OLEDs), where the thickness of ETL is varied to adjust the distance between the emitting zone and the metal electrode. The devices showed a maximum current efficiency of 3.8 cd/A when the ETL thickness is around 50 nm corresponding to an emitter-cathode distance of 80 nm, and a second maximum current efficiency of 2.6 cd/A when the ETL thickness is around 210 nm corresponding to an emitter-cathode distance of 240 nm. We adopt a rigorous electromagnetic approach that takes parameters, such as dipole orientation, polarization, light emitting angle, exciton recombination zone, and diffusion length into account to model the optical properties of devices as a function of varying ETL thickness. Our simulation results are accurately consistent with the experimental results with a widely varying thickness of ETL, indicating that the theoretical model may be helpful to design high efficiency OLEDs.
Numerical identification of epidemic thresholds for susceptible-infected-recovered model on finite-size networks
Authors: Shu Panpan , Wang Wei , Tang Ming , Do Younghae
Published: June 2015

Epidemic threshold has always been a very hot topic for studying epidemic dynamics on complex networks. The previous studies have provided different theoretical predictions of the epidemic threshold for the susceptible-infected-recovered (SIR) model, but the numerical verification of these theoretical predictions is still lacking. Considering that the large fluctuation of the outbreak size occurs near the epidemic threshold, we propose a novel numerical identification method of SIR epidemic threshold by analyzing the peak of the epidemic variability. Extensive experiments on synthetic and real-world networks demonstrate that the variability measure can successfully give the numerical threshold for the SIR model. The heterogeneous mean-field prediction agrees very well with the numerical threshold, except the case that the networks are disassortative, in which the quenched mean-field prediction is relatively close to the numerical threshold. Moreover, the numerical method presented is also suitable for the susceptible-infected-susceptible model. This work helps to verify the theoretical analysis of epidemic threshold and would promote further studies on the phase transition of epidemic dynamics.
The liquid-vapor equilibria of TIP4P/2005 and BLYPSP-4F water models determined through direct simulations of the liquid-vapor interface
Authors: Hu Hongyi , Wang Feng
Published: June 2015

In this paper, the surface tension and critical properties for the TIP4P/2005 and BLYPSP-4F models are reported. A clear dependence of surface tension on the van der Waals cutoff radius (rvdw) is shown when van der Waals interactions are modeled with a simple cutoff scheme. A linear extrapolation formula is proposed that can be used to determine the infinite rvdw surface tension through a few simulations with finite rvdw. A procedure for determining liquid and vapor densities is proposed that does not require fitting to a profile function. Although the critical temperature of water is also found to depend on the choice of rvdw, the dependence is weaker. We argue that a rvdw of 1.75 nm is a good compromise for water simulations when long-range van der Waals correction is not applied. Since the majority of computational programs do not support rigorous treatment of long-range dispersion, the establishment of a minimal acceptable rvdw is important for the simulation of a variety of inhomogeneous systems, such as water bubbles, and water in confined environments. The BLYPSP-4F model predicts room temperature surface tension marginally better than TIP4P/2005 but overestimates the critical temperature. This is expected since only liquid configurations were fit during the development of the BLYPSP-4F potential. The potential is expected to underestimate the stability of vapor and thus overestimate the region of stability for the liquid.
A compact design for the Josephson mixer: The lumped element circuit
Authors: Pillet J.-D. , Flurin E. , Mallet F. , Huard B.
Published: June 2015

We present a compact and efficient design in terms of gain, bandwidth, and dynamical range for the Josephson mixer, the superconducting circuit performing three-wave mixing at microwave frequencies. In an all lumped-element based circuit with galvanically coupled ports, we demonstrate nondegenerate amplification for microwave signals over a bandwidth up to 50 MHz for a power gain of 20 dB. The quantum efficiency of the mixer is shown to be about 70%, and its saturation power reaches −112 dBm.
Inverse spin Hall effect in Pt/(Ga,Mn)As
Authors: Nakayama H. , Chen L. , Chang H. W. , Ohno H. , Matsukura F.
Published: June 2015

We investigate dc voltages under ferromagnetic resonance in a Pt/(Ga,Mn)As bilayer structure. A part of the observed dc voltage is shown to originate from the inverse spin Hall effect. The sign of the inverse spin Hall voltage is the same as that in Py/Pt bilayer structure, even though the stacking order of ferromagnetic and nonmagnetic layers is opposite to each other. The spin mixing conductance at the Pt/(Ga,Mn)As interface is determined to be of the order of 1019 m−2, which is about ten times greater than that of (Ga,Mn)As/p-GaAs.
Increased p-type conductivity through use of an indium surfactant in the growth of Mg-doped GaN
Authors: Kyle Erin C. H. , Kaun Stephen W. , Young Erin C. , Speck James S.
Published: June 2015

We have examined the effect of an indium surfactant on the growth of p-type GaN by ammonia-based molecular beam epitaxy. p-type GaN was grown at temperatures ranging from 700 to 780 °C with and without an indium surfactant. The Mg concentration in all films in this study was 4.5–6 × 1019 cm−3 as measured by secondary ion mass spectroscopy. All p-type GaN films grown with an indium surfactant had higher p-type conductivities and higher hole concentrations than similar films grown without an indium surfactant. The lowest p-type GaN room temperature resistivity was 0.59 Ω-cm, and the highest room temperature carrier concentration was 1.6 × 1018 cm−3. Fits of the temperature-dependent carrier concentration data showed a one to two order of magnitude lower unintentional compensating defect concentration in samples grown with the indium surfactant. Samples grown at higher temperature had a lower active acceptor concentration. Improvements in band-edge luminescence were seen by cathodoluminescence for samples grown with the indium surfactant, confirming the trends seen in the Hall data.
Jamming and unjamming transition of oil-in-water emulsions under continuous temperature change
Authors: Choi Se Bin , Lee Joon Sang
Published: June 2015

To analyze the jamming and unjamming transition of oil-in-water emulsions under continuous temperature change, we simulated an emulsion system whose critical volume fraction was 0.3, which was validated with experimental results under oscillatory shear stress. In addition, we calculated the elastic modulus using the phase lag between strain and stress. Through heating and cooling, the emulsion experienced unjamming and jamming. A phenomenon—which is when the elastic modulus does not reach the expected value at the isothermal system—occurred when the emulsion system was cooled. We determined that this phenomenon was caused by the frequency being faster than the relaxation of the deformed droplets. We justified the relation between the frequency and relaxation by simulating the frequency dependency of the difference between the elastic modulus when cooled and the expected value at the same temperature.
Acetylenes from Aldehydes. Preparation of Ethynylphenols and Phenylacetylenes by Flash Vacuum Pyrolysis of Isoxazolones
Authors: Wentrup Curt , Wiedenstritt Maria , Winter Hans-Wilhelm
Published: June 2015

The flash vacuum pyrolysis method of synthesis of acetylenes from aldehydes via isoxazolones is a convenient method for the preparation of a variety of derivatives, including kinetically unstable, sensitive compounds such as the ethynylphenols.
Type IV pili mechanochemically regulate virulence factors in
Pseudomonas aeruginosa
Authors: Persat Alexandre , Inclan Yuki F. , Engel Joanne N. , Stone Howard A. , Gitai Zemer
Published: June 2015

Significance

In their natural environments, bacteria frequently transition from a free-swimming state to a surface-associated state, attached to a substratum. As they encounter a surface, they may initiate developmental programs to optimally colonize this new environment and induce pathways such as virulence. Here we demonstrate that the pathogen
Pseudomonas aeruginosa
uses fiber-like motorized appendages called type IV pili to sense initial contact with surfaces. This leads to a signaling cascade that results in the expression of hundreds of genes associated with pathogenicity and surface-specific twitching motility. Thus, bacteria use pili not only to attach and move, but also to sense mechanical features of their environment and regulate cellular processes of surface-associated lifestyles.
Adventure learning as a curricular approach that transcends geographies and connects people to place
Authors: Miller Brant G. , Cox Christopher J. , Hougham R. Justin , Walden Von P. , Eitel Karla Bradley , Albano Anthony D.
Published: June 2015

Effectively communicating scientific research has taken on greater importance as climate change impacts the world we live in. It is increasingly incumbent upon the science and education communities to produce and deliver curriculum that is timely, accessible, and scientifically accurate. In the summer of 2012, scientists and educators worked together to develop and conduct the Adventure Learning @ Greenland (AL@GL) project, which explored the capacity of hands‐on and web‐based climate science education experiences that occurred in Greenland and the US. The Adventure Learning approach and associated framework was used to design the learning experience during AL@GL activities. Participating students were from Greenland, Denmark, and the US; these students included participants who were diverse, rural, and traditionally underrepresented. Participating students worked closely with educators and scientists to learn about an atmospheric observatory at Summit Station, located on the Greenland Ice Sheet. The purpose of this article is to inform readers in how they may use Adventure Learning and the newly developed curriculum model called Content, Transition, Inquiry, and Synthesis for the education and outreach of research projects.
The Business of Prostitution in Early Renaissance Venice*
Authors: Clarke Paula C.
Published: June 2015

Between 1360 and 1460 the Venetian government established a system of legalized prostitution under the supervision of government officials and confined, in theory, to a limited area of the city. The authorities also attempted to concentrate the management of licit brothels in the hands of women, who thereby emerged as the effective entrepreneurs of the sex trade. This article describes the organization of Venetian prostitution in the late fourteenth and early fifteenth centuries and the relations among government officials, brothel-keepers, and prostitutes. It illustrates the mechanisms of debt and credit used in the sex trade, which often kept the prostitutes subservient to the brothel-keepers and to their other creditors. An effort is made to assess the degree to which sex workers might become integrated into local society and to suggest the general trends in Venetian policy toward prostitution into the sixteenth century.
Multipliers for noncommutative Walsh-Fourier series
Authors: Wu Lian
Published: June 2015

We consider multipliers for noncommutative Walsh-Fourier series. Let

R

\mathcal {R}

be the type

I

I
1

II_1

hyperfinite factor. For

x
∈

L
1

(

R

)

x \in L_1(\mathcal {R})

,

0
>
α
>
1

0>\alpha >1

, the multiplier transformation of

x
x

is defined by setting
\[
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper J Superscript alpha Baseline x equals sigma-summation Underscript gamma element-of script upper F Endscripts 2 Superscript minus gamma left-parenthesis 1 right-parenthesis alpha Baseline ModifyingAbove x With caret left-parenthesis gamma right-parenthesis w Subscript gamma Baseline comma">

J
α

x
=

∑

γ
∈

F

2

−
γ
(
1
)
α

x
^

(
γ
)

w
γ

,

J^\alpha x = \sum _{\gamma \in \mathcal {F}}2^{-\gamma (1)\alpha }\hat {x}(\gamma )w_\gamma ,

\]
where

(

w
γ

)

γ
∈

F

(w_\gamma )_{\gamma \in \mathcal {F}}

is the noncommutative Walsh system in

R

\mathcal {R}

and

∑

γ
∈

F

x
^

(
γ
)

w
γ

\sum _{\gamma \in \mathcal {F}}\hat {x}(\gamma )w_\gamma

is the Walsh-Fourier series of

x
x

. It is shown that
\[
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="double-vertical-bar upper J Superscript alpha Baseline x double-vertical-bar Subscript upper L Sub Subscript 1 slash left-parenthesis 1 minus alpha right-parenthesis comma normal infinity Subscript left-parenthesis script upper R right-parenthesis Baseline less-than-or-equal-to c double-vertical-bar x double-vertical-bar Subscript upper L 1 left-parenthesis script upper R right-parenthesis Baseline comma">

‖

J
α

x

‖

L

1

/

(
1
−
α
)
,
∞

(

R

)

≤
c
‖
x

‖

L
1

(

R

)

,

\|J^\alpha x\|_{L_{1/(1-\alpha ),\infty }(\mathcal {R})}\leq c \|x\|_{L_1(\mathcal {R})},

\]
where

c
c

is a constant depending only on

α
\alpha

. Via interpolations, we deduce that

J
α

J^\alpha

is bounded from

L

p

(

R

)

L_{p}(\mathcal {R})

into

L

q

(

R

)

L_{q}(\mathcal {R})

where

1
>
p
>
q

1>p>q

and

α
=
1

/

p
−
1

/

q

\alpha =1/p-1/q

, thus providing a noncommutative analogue of a classical result of Watari.
Nuclear pore complex integrity requires Lnp1, a regulator of cortical endoplasmic reticulum
Authors: Casey Amanda K. , Chen Shuliang , Novick Peter , Ferro-Novick Susan , Wente Susan R.
Published: June 2015

The nuclear envelope (NE) and endoplasmic reticulum (ER) are components of the same contiguous membrane system and yet have distinct cellular functions. Mounting evidence suggests roles for some ER proteins in the NE for proper nuclear pore complex (NPC) structure and function. In this study, we identify a NE role in Saccharomyces cerevisiae for Lnp1 and Sey1, proteins required for proper cortical ER formation. Both lnp1Δ and sey1Δ mutants exhibit synthetic genetic interactions with mutants in genes encoding key NPC structural components. Both Lnp1 and Sey1 physically associate with other ER components that have established NPC roles, including Rtn1, Yop1, Pom33, and Per33. Of interest, lnp1Δ rtn1Δ mutants but not rtn1Δ sey1Δ mutants exhibit defects in NPC distribution. Furthermore, the essential NPC assembly factor Ndc1 has altered interactions in the absence of Sey1. Lnp1 dimerizes in vitro via its C-terminal zinc finger motif, a property that is required for proper ER structure but not NPC integrity. These findings suggest that Lnp1's role in NPC integrity is separable from functions in the ER and is linked to Ndc1 and Rtn1 interactions.
Assembling short reads from jumping libraries with large insert sizes
Authors: Vasilinetc Irina , Prjibelski Andrey D. , Gurevich Alexey , Korobeynikov Anton , Pevzner Pavel A.
Published: June 2015

Motivation: Advances in Next-Generation Sequencing technologies and sample preparation recently enabled generation of high-quality jumping libraries that have a potential to significantly improve short read assemblies. However, assembly algorithms have to catch up with experimental innovations to benefit from them and to produce high-quality assemblies.

Results: We present a new algorithm that extends recently described exSPAnder universal repeat resolution approach to enable its applications to several challenging data types, including jumping libraries generated by the recently developed Illumina Nextera Mate Pair protocol. We demonstrate that, with these improvements, bacterial genomes often can be assembled in a few contigs using only a single Nextera Mate Pair library of short reads.

Availability and implementation: Described algorithms are implemented in C++ as a part of SPAdes genome assembler, which is freely available at bioinf.spbau.ru/en/spades.

Contact:  ap@bioinf.spbau.ru

Supplementary information:  Supplementary data are available at Bioinformatics online.
TiQuant: software for tissue analysis, quantification and surface reconstruction
Authors: Friebel Adrian , Neitsch Johannes , Johann Tim , Hammad Seddik , Hengstler Jan G. , Drasdo Dirk , Hoehme Stefan
Published: June 2015

Motivation: TiQuant is a modular software tool for efficient quantification of biological tissues based on volume data obtained by biomedical image modalities. It includes a number of versatile image and volume processing chains tailored to the analysis of different tissue types which have been experimentally verified. TiQuant implements a novel method for the reconstruction of three-dimensional surfaces of biological systems, data that often cannot be obtained experimentally but which is of utmost importance for tissue modelling in systems biology.

Availability and implementation: TiQuant is freely available for non-commercial use at msysbio.com/tiquant. Windows, OSX and Linux are supported.

Contact:  hoehme@uni-leipzig.de

Supplementary information:  Supplementary data are available at Bioinformatics online.
A young stellar environment for the superluminous supernova PTF12dam
Authors: Thöne C. C. , de Ugarte Postigo A. , García-Benito R. , Leloudas G. , Schulze S. , Amorín R.
Published: June 2015

The progenitors of superluminous supernovae (SLSNe) are still a mystery. Hydrogen-poor SLSN hosts are young, highly star-forming dwarf galaxies and the majority belongs to the class of ‘extreme emission line galaxies’. Here we present a resolved long-slit study of the host of the hydrogen-poor SLSN PTF12dam probing the kiloparsec environment of the SN site to determine the age of the progenitor. The SN occurred in a star-forming region in the head of a ‘tadpole’ galaxy with largely uniform properties. The galaxy experienced a recent starburst superimposed on an underlying old stellar population (SP). We determine a very young SP at the SN site of ∼3 Myr and a metallicity of 12+log(O/H)=8.0 but do not observe any Wolf–Rayet features. The progenitor of PTF12dam was likely a massive star of >60 M⊙ and one of the first stars exploding as an SN in the most recent starburst episode.
Shaping the X-ray spectrum of galaxy clusters with AGN feedback and turbulence
Authors: Gaspari M.
Published: June 2015

The hot plasma filling galaxy clusters emits copious X-ray radiation. The classic unheated and unperturbed cooling flow model predicts dramatic cooling rates and an isobaric X-ray spectrum with constant differential luminosity distribution. The observed cores of clusters (and groups) show instead a strong deficit of soft X-ray emission: dLx/dT ∝ (T/Thot)α = 2 ± 1. Using 3D hydrodynamic simulations, we show that such deficit arises from the tight self-regulation between thermal instability condensation and AGN outflow injection: condensing clouds boost the AGN outflows, which quench cooling as they thermalize through the core. The resultant average distribution slope is α ≃ 2, oscillating within the observed 1 < α < 3. In the absence of thermal instability, the X-ray spectrum remains isothermal (α ≳ 8), while unopposed cooling drives a too shallow slope, α < 1. AGN outflows deposit their energy inside-out, releasing more heat in the inner cooler phase; radially distributed heating alone induces a declining spectrum, 1 < α < 2. Turbulence further steepens the spectrum and increases the scatter: the turbulent Mach number in the hot phase is subsonic, while it becomes transonic in the cooler phase, making perturbations to depart from the isobaric mode. Such increase in dln P/dln T leads to α ≈ 3. Self-regulated AGN outflow feedback can address the soft X-ray problem through the interplay of heating and turbulence.
The dust mass in z > 6 normal star-forming galaxies
Authors: Mancini Mattia , Schneider Raffaella , Graziani Luca , Valiante Rosa , Dayal Pratika , Maio Umberto , Ciardi Benedetta , Hunt Leslie K.
Published: June 2015

We interpret recent ALMA observations of z > 6 normal star-forming galaxies by means of a seminumerical method, which couples the output of a cosmological hydrodynamical simulation with a chemical evolution model which accounts for the contribution to dust enrichment from supernovae, asymptotic giant branch stars and grain growth in the interstellar medium. We find that while stellar sources dominate the dust mass of small galaxies, the higher level of metal enrichment experienced by galaxies with Mstar > 109 M⊙ allows efficient grain growth, which provides the dominant contribution to the dust mass. Even assuming maximally efficient supernova dust production, the observed dust mass of the z = 7.5 galaxy A1689-zD1 requires very efficient grain growth. This, in turn, implies that in this galaxy the average density of the cold and dense gas, where grain growth occurs, is comparable to that inferred from observations of quasar (QSO) host galaxies at similar redshifts. Although plausible, the upper limits on the dust continuum emission of galaxies at 6.5 < z < 7.5 show that these conditions must not apply to the bulk of the high-redshift galaxy population.
Rehabilitation of motor dysfunction in primary brain tumor patients†
Authors: Kushner David S. , Amidei Christina
Published: June 2015

In 2010 it was estimated that >688 000 Americans were living with a primary brain tumor (PBT) corresponding to a U.S. prevalence rate of approximately 221.8 per 100 000 people. Five-year survival is 96.1% in nonmalignant PBTs, 34% in malignant PBTs for all ages, and 71% in children [1985–2005]. Case fatality rates have decreased in the U.S. since the 1970's for nonmalignant PBTs and for medulloblastoma, oligodendroglioma, and astrocytoma. Statistics of increasing survival highlight the importance of rehabilitation interventions to improve function and quality of life in survivors. PBT motor dysfunction is multifactorial, occurring as a result of direct effects of tumor and/or swelling or as a result of treatments; etiologies include encephalopathy, myopathy, neuropathy, infection, poor nutrition, metabolic factors, emotional factors, impaired perception/vision/cognition and complications of immobility. Motor dysfunction may lead to: impaired mobility, impaired activities of daily living, risk for complications of immobility, falls, pain, anxiety/depression, and loss of functional independence and quality of life. Rehabilitation treatment strategies target specific causes of motor dysfunction to improve functional independence and quality of life. This article reviews current knowledge and controversy regarding the role of rehabilitation for motor disorders in PBT patients.
Incidence and Costs of Clostridium difficile Infections in Canada
Authors: Levy Adrian R. , Szabo Shelagh M. , Lozano-Ortega Greta , Lloyd-Smith Elisa , Leung Victor , Lawrence Robin , Romney Marc G.
Published: June 2015

Background.  Limited data are available on direct medical costs and lost productivity due to Clostridium difficile infection (CDI) in Canada.

Methods.  We developed an economic model to estimate the costs of managing hospitalized and community-dwelling patients with CDI in Canada. The number of episodes was projected based on publicly available national rates of hospital-associated CDI and the estimate that 64% of all CDI is hospital-associated. Clostridium difficile infection recurrences were classified as relapses or reinfections. Resource utilization data came from published literature, clinician interviews, and Canadian CDI surveillance programs, and this included the following: hospital length of stay, contact with healthcare providers, pharmacotherapy, laboratory testing, and in-hospital procedures. Lost productivity was considered for those under 65 years of age, and the economic impact was qua.jpegied using publicly available labor statistics. Unit costs were obtained from published sources and presented in 2012 Canadian dollars.

Results.  There were an estimated 37 900 CDI episodes in Canada in 2012; 7980 (21%) of these were relapses, out of a total of 10 900 (27%) episodes of recurrence. The total cost to society of CDI was estimated at $281 million; 92% ($260 million) was in-hospital costs, 4% ($12 million) was direct medical costs in the community, and 4% ($10 million) was due to lost productivity. Management of CDI relapses alone accounted for $65.1 million (23%).

Conclusions.  The largest proportion of costs due to CDI in Canada arise from extra days of hospitalization. Interventions reducing the severity of infection and/or relapses leading to rehospitalizations are likely to have the largest absolute effect on direct medical costs.
Appearance of the prolate and the toroidal magnetic field dominated stars: Analytic approach
Authors: Fujisawa Kotaro , Eriguchi Yoshiharu
Published: June 2015

We have analyzed magnetized equilibrium states and shown a condition for the appearance of the prolate and the toroidal magnetic field-dominated stars using analytic approaches. Both observations and numerical stability analysis support that the magnetized star would have prolate and large internal toroidal magnetic fields. In this context, many investigations concerning magnetized equilibrium states have been tried to obtain the prolate and the toroidal dominant solutions, but many of them have failed to obtain such configurations. Since the Lorentz force is a cross-product of current density and magnetic field, the prolate-shaped configurations and the large toroidal magnetic fields in stars require a special relation between current density and the Lorentz force. We have analyzed simple analytical solutions and found that the prolate and the toroidal-dominant configuration require non-force-free toroidal current density that flows in the opposite direction with respect to the bulk current within the star. Such current density results in the Lorentz force which makes the stellar shape prolate. Satisfying this special relation between the current density and the Lorentz force is a key to the appearance of the prolate and the toroidal magnetic field-dominated magnetized star.
Chemical feature of Eu abundance in the Draco dwarf spheroidal galaxy
Authors: Tsujimoto Takuji , Ishigaki Miho N. , Shigeyama Toshikazu , Aoki Wako
Published: June 2015

The chemical abundance of r-process elements in nearby dwarf spheroidal (dSph) galaxies is a powerful tool to probe the site of r-process since their small-mass scale can assess the potential rarity of events associated with the r-process production. A merger of binary neutron stars is a promising candidate for such a site. In faint, or less-massive, dSph galaxies such as the Draco, a few binary neutron star mergers are expected to have occurred at most over the whole past. We have measured the chemical abundance, including Eu and Ba, of three red giants in the Draco dSph by Subaru High-Dispersion Spectrograph observation. The Eu detection for one star with [Fe/H] = −1.45 confirms a broadly constant [Eu/H] of ∼ −1.3 for stars with [Fe/H] ${\buildrel {>} \over \sim}-2$. This feature is shared by other dSphs with similar masses, i.e., the Sculptor and the Carina, and suggests that a neutron star merger is the origin of r-process elements in terms of the rarity of this event. In addition, two very metal-poor stars with [Fe/H] = −2.12 and −2.51 are found to exhibit very low Eu abundances, such as [Eu/H] < −2, with the suggestion of a sudden increase of Eu abundance by more than 0.7 dex at [Fe/H] ≈ −2.2 in the Draco dSph. The detection of Ba abundances for these stars suggests that the r-process enrichment began no later than the time when only a few percent of stars in the present-day Draco dSph were formed. Though identifying the origin of an early Eu production inside the Draco dSph should be left until more abundant data of stars with [Fe/H] ${\buildrel {<} \over \sim }$−2 in Draco, as well as other faint dSphs, become available, the implied early emergence of an Eu production event might be reconciled with the presence of extremely metal-poor stars enriched by r-process elements in the Galactic halo.
Association between Withholding Angiotensin Receptor Blockers in the Early Postoperative Period and 30-day Mortality
Authors: Lee Susan M. , Takemoto Steven , Wallace Arthur W.
Published: June 2015

AbstractAbstract

In a review of over 30,000 inpatient surgical admissions of patients taking angiotensin receptor blockers (ARBs) in the Veterans Affairs Healthcare system between 1991 and 2011, ARBs were not resumed by day 2 after surgery in one third of subjects. Thirty-day mortality was increased approximately 50% in those without resumption of ARBs, and this effect was even greater in patients younger than 60 yr.

Supplemental Digital Content is available in the text.

Background:

Despite widespread use, there is limited information to guide perioperative management of angiotensin receptor blockers (ARBs).

Methods:

In this retrospective cohort study, the authors evaluated the patterns of postoperative ARB use in veterans regularly prescribed ARBs admitted for noncardiac surgery at the Veterans Affairs Healthcare system between 1999 and 2011. Multivariable and propensity score–matched Cox proportional hazards models were used to determine the independent effect of failure to resume ARB by postoperative day 2 on the primary outcome of all-cause 30-day mortality.

Results:

Out of 1,167,482 surgical admissions, 30,173 inpatient surgical admissions met inclusion criteria. Approximately 10,205 patients (33.8%) in the cohort did not resume ARB by day 2. Those that resumed ARB had a 30-day mortality rate of 1.3% (260 of 19,968), whereas 3.2% (323 of 10,205) died in the group that withheld ARB. The unadjusted hazard ratio (HR) for 30-day mortality was 2.45 (95% CI, 2.08 to 2.89; P < 0.001) for those that withheld ARB compared with those that resumed, whereas the multivariable adjusted HR was 1.74 (95% CI, 1.47 to 2.06; P < 0.001). When restricted to a propensity score–matched subset of 19,490, the HR was similar (1.47; 95% CI, 1.22 to 1.78; P < 0.001). Withholding ARB in younger patients increased mortality risk (HR = 2.52; 95% CI, 1.69 to 3.76; P < 0.001 for age <60 yr) compared with older patients (HR = 1.42; 95% CI, 1.09 to 1.85; P = 0.01 for age >75 yr).

Conclusions:

Postoperative delay in resuming ARB is common, particularly in patients who are frail after surgery. Withholding ARB is strongly associated with increased 30-day mortality, especially in younger patients, although residual confounding may be present.
Esophageal pH Monitoring in Children
Authors: Nowak Jan K. , Jonczyk‐Potoczna Katarzyna , Adamczak Daria M. , Lisowska Aleksandra , Walkowiak Jaroslaw
Published: June 2015

Correct pH probe placement is vital for the precision of esophageal pH monitoring. This study aimed at finding the optimal formula for placement of pH probe in the locus proposed by the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition European Pediatric Impedance Working Group, that is, 2 vertebrae above the diaphragm. An analysis of data regarding 353 children ages 0–18 years in whom the position of the pH sensor was determined radiographically revealed that a mathematical formula (3.2 + 0.2 × body length or height, centimeter) could guide the probe to within 1/12 of thoracic spine length of the desired location in 71.7% of all of the patients.
P‐Selectin (CD62P) Expression in Liver Tissue of Biliary Atresia
Authors: Sira Mostafa M. , Sira Ahmad M. , Ehsan Nermine A. , Mosbeh Asmaa
Published: June 2015

Objectives:

The etiology of biliary atresia (BA) is still elusive. Inflammation plays a key role in bile duct and liver injury. The recruitment and accumulation of inflammatory cells is largely dependent on adhesion molecules. We aimed to investigate P‐selectin (CD62P) expression in liver tissue in patients with BA compared with other neonatal cholestatic disorders.

Methods:

The study included 63 infants with neonatal cholestasis in 2 groups: BA group (n = 32) and non‐BA group (n = 31) with non‐BA cholestatic disorders as controls. Demographic, clinical, laboratory, ultrasonographic, and histopathological parameters were collected. P‐selectin immunostaining was performed. Immunostaining in bile duct epithelium, cellular infiltrate, and vascular endothelial cells were scored as positive or negative.

Results:

The frequency of P‐selectin–positive endothelium, platelets, and bile duct epithelium was significantly higher in the BA group (72%, 72%, and 63%, respectively) than in the non‐BA group (32%, 16%, and 13%, respectively) with P of 0.002, <0.0001, and <0.0001, respectively. Few mononuclear cellular infiltrates in portal tract expressed P‐selectin and were comparable in both groups (P = 0.932). Of interest, the platelet count was significantly higher in the BA group (532 ± 172) than in the non‐BA group (406 ± 158), and 68.8% of the BA group had thrombocytosis versus 25% in the controls (P = 0.001 for both).

Conclusions:

The significant expression of P‐selectin in endothelium, platelets, and bile duct epithelium in patients with BA suggests a potential role for this adhesion molecule in the pathogenesis of this devastating neonatal hepatic disorder. It further suggests that platelets in BA are activated and may have a role in the inflammatory process in BA.
A semi-supervised approach uncovers thousands of intragenic enhancers differentially activated in human cells
Authors: González-Vallinas Juan , Pagés Amadis , Singh Babita , Eyras Eduardo
Published: June 2015

Background

Transcriptional enhancers are generally known to regulate gene transcription from afar. Their activation involves a series of changes in chromatin marks and recruitment of protein factors. These enhancers may also occur inside genes, but how many may be active in human cells and their effects on the regulation of the host gene remains unclear.

Results

We describe a novel semi-supervised method based on the relative enrichment of chromatin signals between 2 conditions to predict active enhancers. We applied this method to the tumoral K562 and the normal GM12878 cell lines to predict enhancers that are differentially active in one cell type. These predictions show enhancer-like properties according to positional distribution, correlation with gene expression and production of enhancer RNAs. Using this model, we predict 10,365 and 9,777 intragenic active enhancers in K562 and GM12878, respectively, and relate the differential activation of these enhancers to expression and splicing differences of the host genes.

Conclusions

We propose that the activation or silencing of intragenic transcriptional enhancers modulate the regulation of the host gene by means of a local change of the chromatin and the recruitment of enhancer-related factors that may interact with the RNA directly or through the interaction with RNA binding proteins. Predicted enhancers are available athttp://regulatorygenomics.upf.edu/Projects/enhancers.html
Evolution of ecological dominance of yeast species in high-sugar environments
Authors: Williams Kathryn M. , Liu Ping , Fay Justin C.
Published: June 2015

In budding yeasts, fermentation in the presence of oxygen evolved around the time of a whole genome duplication (WGD) and is thought to confer dominance in high-sugar environments because ethanol is toxic to many species. While there are many fermentative yeast species, onlySaccharomyces cerevisiaeconsistently dominates wine fermentations. In this study, we use co-culture experiments and intrinsic growth rate assays to examine the relative fitness of non-WGD and WGD yeast species across environments to assess whenS. cerevisiae’s ability to dominate high-sugar environments arose. We show thatS. cerevisiaedominates nearly all other non-WGD and WGD species except for its sibling speciesS. paradoxusin both grape juice and a high-sugar rich medium. Of the species we tested,S. cerevisiaeandS. paradoxushave evolved the highest ethanol tolerance and intrinsic growth rate in grape juice. However, the ability ofS. cerevisiaeandS. paradoxusto dominate certain species depends on the temperature and the type of high-sugar environment. Our results indicate that dominance of high-sugar environments evolved much more recently than the WGD, most likely just prior to or during the differentiation ofSaccharomycesspecies, and that evolution of multiple traits contributes toS. cerevisiae’s ability to dominate wine fermentations.
Rapid metagenomic identification of viral pathogens in clinical samples by real-time nanopore sequencing analysis
Authors: Greninger Alex L , Naccache Samia N , Federman Scot , Yu Guixia , Mbala Placide , Bres Vanessa , Bouquet Jerome , Stryke Doug , Somasekar Sneha , Linnen Jeffrey , Dodd Roger , Mulembakani Prime , Schneider Bradley , Muyembe Jean-Jacques , Stramer Susan , Chiu Charles Y
Published: June 2015

We report unbiased metagenomic detection of chikungunya virus (CHIKV), Ebola virus (EBOV), and hepatitis C virus (HCV) from four human blood samples by MinION nanopore sequencing coupled to a newly developed, web-based pipeline for real-time bioinformatics analysis on a computational server or laptop(MetaPORE). At titers ranging from 107-108 copies per milliliter, reads to EBOV from two patients with acute hemorrhagic fever and CHIKV from an asymptomatic blood donor were detected within 4 to 10 minutes of data acquisition, while lower titer HCV virus (1x105 copies per milliliter) was detected within 40 minutes. Analysis of mapped nanopore reads alone, despite an average individual error rate of 24% [range 8-49%], permitted identification of the correct viral strain in all 4 isolates, and 90% of the genome of CHIKV was recovered with >98% accuracy. Using nanopore sequencing, metagenomic detection of viral pathogens directly from clinical samples was performed within an unprecedented <6 hours sample-to-answer turnaround time and in a timeframe amenable for actionable clinical and public health diagnostics.
Ethylene-Mediated Regulation of A2-Type CYCLINs Modulates Hyponastic Growth in Arabidopsis
Authors: Polko Joanna K. , van Rooij Jop A. , Vanneste Steffen , Pierik Ronald , Ammerlaan Ankie M.H. , Vergeer-van Eijk Marleen H. , McLoughlin Fionn , Gühl Kerstin , Van Isterdael Gert , Voesenek Laurentius A.C.J. , Millenaar Frank F. , Beeckman Tom , Peeters Anton J.M. , Marée Athanasius F.M. , van Zanten Martijn
Published: June 2015

Upward leaf movement (hyponastic growth) is frequently observed in response to changing environmental conditions and can be induced by the phytohormone ethylene. Hyponasty results from differential growth (i.e. enhanced cell elongation at the proximal abaxial side of the petiole relative to the adaxial side). Here, we characterize Enhanced Hyponasty-d, an activation-tagged Arabidopsis (Arabidopsis thaliana) line with exaggerated hyponasty. This phenotype is associated with overexpression of the mitotic cyclin CYCLINA2;1 (CYCA2;1), which hints at a role for cell divisions in regulating hyponasty. Indeed, mathematical analysis suggested that the observed changes in abaxial cell elongation rates during ethylene treatment should result in a larger hyponastic amplitude than observed, unless a decrease in cell proliferation rate at the proximal abaxial side of the petiole relative to the adaxial side was implemented. Our model predicts that when this differential proliferation mechanism is disrupted by either ectopic overexpression or mutation of CYCA2;1, the hyponastic growth response becomes exaggerated. This is in accordance with experimental observations on CYCA2;1 overexpression lines and cyca2;1 knockouts. We therefore propose a bipartite mechanism controlling leaf movement: ethylene induces longitudinal cell expansion in the abaxial petiole epidermis to induce hyponasty and simultaneously affects its amplitude by controlling cell proliferation through CYCA2;1. Further corroborating the model, we found that ethylene treatment results in transcriptional down-regulation of A2-type CYCLINs and propose that this, and possibly other regulatory mechanisms affecting CYCA2;1, may contribute to this attenuation of hyponastic growth.
Explore the feasibility of adopting crowdsourcing for innovative problem solving
Authors: Lee C.K.M. , Chan CY , Ho Sophie , Choy KL , Ip WH
Published: June 2015

Purpose

– The purpose of this paper is to explore the feasibility of adopting crowdsourcing for enhancing innovative problem solving through task design on task attributes. Task attributes have been proven to be an important factor influencing participation and engagement of crowdworkers.

Design/methodology/approach

– A survey questionnaire was developed and data from potential and experienced crowdworkers was collected and analyzed to identify the influence of task attributes on the quantity and quality of innovative solutions from crowds. This study finds that extrinsic and intrinsic motivation of task attributes are linked to psychological participation attention and the contribution of innovative solutions.

Findings

– It is found that crowdsourcing projects with higher awards and recognition as extrinsic motivation is positively associated with the quantity of solution. Competitive selection with performance feedback, problems with diversity of knowledge and job autonomy with more information from sponsors are positive associate with the quality of innovative solutions. These results can complement existing research studies on how task attributes influence the performance of existing crowdworkers in crowdsourcing and can also be a starting point for analyzing potential crowdworkers’ psychological perspectives.

Originality/value

– The novelty of this paper is that it illustrates the influential effects of five selected task attributes – monetary rewards and recognition, competitive selection, knowledge diversity, task complexity and autonomy – to enhance extrinsic and intrinsic motivation toward crowdsourcing feasibility in terms of quantity and quality of innovative solutions.
Franchising decision support system for formulating a center positioning strategy
Authors: Wu C.H. , Ho G.T.S. , Lam Cathy H. Y. , Ip W.H.
Published: June 2015

Purpose

– The purpose of this paper is to propose a franchising decision support system (FDSS) for future development planning by center positioning strategy formulation under a franchising business model.

Design/methodology/approach

– The system makes use of data collected from the franchising business and external environment analysis for decision making in center positioning problems. The fuzzy logic approach is integrated into the system for analyzing the geographical market dynamics including profitability and competitiveness in the district concerned. To demonstrate the application of the proposed FDSS, a case study is conducted in a Hong Kong-based franchising private education center, i.e. Dr I-Kids Education Center.

Findings

– The tailor made FDSS helps to facilitate the business operations of the franchising education center and develops a district positioning model for the centers located in the 18 districts of Hong Kong. The findings provide a solid foundation for marketing strategy and expansion direction formulation.

Originality/value

– Due to the globalization of business, managing a growing franchising business model becomes challenging to the franchisor. In order to fully leverage the merits of the franchising system, an intelligent decision support model, focusing on making strategic development plans, is needed so as to expand the scale of business efficiently.
An exploratory analysis of the relations between the rate of physiological habituation, the acquired capability for suicide, and acute risk factors for suicide
Authors: Smith Phillip N , Wolford-Clevenger Caitlin , Selwyn Candice N , Poindexter Erin , Lechner William , Grant DeMond M. , Cukrowicz Kelly C
Published: June 2015

Purpose

– The interpersonal theory of suicide proposes that an individual must acquire the capability for suicide to carry out a near-lethal or lethal suicide attempt. This capability develops via habituation in response to painful and provocative life events. Some individuals might be more vulnerable to developing the capability for suicide because they habituate more quickly to stimuli. The purpose of this paper is to examine the relations between the rate of physiological habituation and acquired capability, proxies for acquired capability, and acute risk factors for suicide.

Design/methodology/approach

– Depressed, suicidal individuals completed self-report assessments and a startle reflex task assessing the rate or speed of physiological habituation in response to repeated bursts of white noise.

Findings

– Slower habituation was associated with hopelessness and negative stressors. The rate of habituation was not associated with acquired capability.

Originality/value

– The current study informs the understanding of how physiological habituation is related to suicide risk factors.