bluuebunny/crossref_metadata_2025 huggingface dataset:
Machine learning-based screening of complex molecules for polymer solar cells
Authors: Jørgensen Peter Bjørn , Mesta Murat , Shil Suranjan , García Lastra Juan Maria , Jacobsen Karsten Wedel , Thygesen Kristian Sommer , Schmidt Mikkel N.
Published: June 2018

Polymer solar cells admit numerous potential advantages including low energy payback time and scalable high-speed manufacturing, but the power conversion efficiency is currently lower than for their inorganic counterparts. In a Phenyl-C_61-Butyric-Acid-Methyl-Ester (PCBM)-based blended polymer solar cell, the optical gap of the polymer and the energetic alignment of the lowest unoccupied molecular orbital (LUMO) of the polymer and the PCBM are crucial for the device efficiency. Searching for new and better materials for polymer solar cells is a computationally costly affair using density functional theory (DFT) calculations. In this work, we propose a screening procedure using a simple string representation for a promising class of donor-acceptor polymers in conjunction with a grammar variational autoencoder. The model is trained on a dataset of 3989 monomers obtained from DFT calculations and is able to predict LUMO and the lowest optical transition energy for unseen molecules with mean absolute errors of 43 and 74 meV, respectively, without knowledge of the atomic positions. We demonstrate the merit of the model for generating new molecules with the desired LUMO and optical gap energies which increases the chance of finding suitable polymers by more than a factor of five in comparison to the randomised search used in gathering the training set.
Thickness dependence of crystal and optical characterization on ZnO thin film grown by atomic layer deposition
Authors: Baek Seung-Hye , Lee Hyun-Jin , Lee Sung-Nam
Published: June 2018

We studied the thickness dependence of the crystallographic and optical properties of ZnO thin films grown on c-plane sapphire substrate using atomic layer deposition. High-resolution X-ray diffraction (HR-XRD) revealed two peaks at 34.5° and 36.2° in the initial growth stage of ZnO on the sapphire substrate, corresponding to the (002) and (101) ZnO planes, respectively. However, as the thickness of the ZnO film increased, the XRD intensity of the (002) ZnO peak increased drastically, compared with that of the (101) ZnO peak. This indicated that (002) and (101) ZnO were simultaneously grown on the c-plane sapphire substrate in the initial growth stage, and that (002) ZnO was predominantly grown with the increase in the thickness of ZnO film. The ZnO thin film presented an anisotropic surface structure at the initial stage, whereas the isotropic surface morphology was developed with an increase in the film thickness of ZnO. These observations were consistent with the HR-XRD results.
Diffusion quantum Monte Carlo and density functional calculations of the structural stability of bilayer arsenene
Authors: Kadioglu Yelda , Santana Juan A. , Özaydin H. Duygu , Ersan Fatih , Aktürk O. Üzengi , Aktürk Ethem , Reboredo Fernando A.
Published: June 2018

We have studied the structural stability of monolayer and bilayer arsenene (As) in the buckled (b) and washboard (w) phases with diffusion quantum Monte Carlo (DMC) and density functional theory (DFT) calculations. DMC yields cohesive energies of 2.826(2) eV/atom for monolayer b-As and 2.792(3) eV/atom for w-As. In the case of bilayer As, DMC and DFT predict that AA-stacking is the more stable form of b-As, while AB is the most stable form of w-As. The DMC layer-layer binding energies for b-As-AA and w-As-AB are 30(1) and 53(1) meV/atom, respectively. The interlayer separations were estimated with DMC at 3.521(1) Å for b-As-AA and 3.145(1) Å for w-As-AB. A comparison of DMC and DFT results shows that the van der Waals density functional method yields energetic properties of arsenene close to DMC, while the DFT + D3 method closely reproduced the geometric properties from DMC. The electronic properties of monolayer and bilayer arsenene were explored with various DFT methods. The bandgap values vary significantly with the DFT method, but the results are generally qualitatively consistent. We expect the present work to be useful for future experiments attempting to prepare multilayer arsenene and for further development of DFT methods for weakly bonded systems.
Note: A well-confined pulsed low-energy ion beam: Test experiments of Ar+
Authors: Hu Jie , Wu Chun-Xiao , Tian Shan Xi
Published: June 2018

Here we report a pulsed low-energy ion beam source for ion-molecule reaction study, in which the ions produced by the pulsed electron impact are confined well in the spatial size of each bunch. In contrast to the ion focusing method to reduce the transverse section of the beam, the longitudinal section in the translational direction is compressed by introducing a second pulse in the ion time-of-flight system. The test experiments for the low-energy argon ions are performed. The present beam source is ready for applications in the ion-molecule reaction dynamics experiments, in particular, in combination with the ion velocity map imaging technique.
Discrete cosine and sine transforms generalized to honeycomb lattice
Authors: Hrivnák Jiří , Motlochová Lenka
Published: June 2018

The discrete cosine and sine transforms are generalized to a triangular fragment of the honeycomb lattice. The honeycomb point sets are constructed by subtracting the root lattice from the weight lattice points of the crystallographic root system A2. The two-variable orbit functions of the Weyl group of A2, discretized simultaneously on the weight and root lattices, induce a novel parametric family of extended Weyl orbit functions. The periodicity and von Neumann and Dirichlet boundary properties of the extended Weyl orbit functions are detailed. Three types of discrete complex Fourier-Weyl transforms and real-valued Hartley-Weyl transforms are described. Unitary transform matrices and interpolating behavior of the discrete transforms are exemplified. Consequences of the developed discrete transforms for transversal eigenvibrations of the mechanical graphene model are discussed.
Charge and spin currents in graphene generated by tailored light with orbital angular momentum
Authors: Inglot M. , Dugaev V. K. , Berakdar J. , Sherman E. Ya. , Barnaś J.
Published: June 2018

We analyze the possibility of optical generation of charge and spin currents in graphene by light carrying an orbital angular momentum (OAM). The graphene is assumed to be deposited on a substrate that induces Rashba spin-orbit coupling. In addition, a weak external magnetic field is assumed to be applied in the plane of graphene. We show that the photon absorption and the magnitude of the generated charge and spin currents depend remarkably on the parameters characterizing the light with OAM.
Electromagnetically induced transparency in sinusoidal modulated ring resonator
Authors: Malik Jagannath , Oruganti Sai Kiran , Song Seongkyu , Ko Nak Young , Bien Franklin
Published: June 2018

In the present work, we demonstrate controlling the excitation of bright mode (continuum mode) resonance and dark mode (discrete mode) resonance in a planar metasurface made of sinusoidal modulation inside a closed rectangular metallic ring placed over a dielectric substrate. Unlike asymmetrical breaking of a meta-atom (often referred to as the unit cell) to achieve the dark mode response in regular metamaterials, in the present structure, the bright or dark mode resonance is achieved using even or odd half cycle modulation. The achieved dark-mode shows a sharp resonance for a particular polarization of the incident electric field, which results in an electromagnetically induced transparency like spectrum. The electromagnetic behavior of the proposed meta-atom has been investigated in the frequency domain using commercially available software and validated through experiments in the gigahertz regime.
Printed biomolecular templates for 2D material patterning
Authors: Muratore C. , Juhl A. T. , Stroud A. J. , Wenbi Lai D. , Jawaid A. M. , Burzynski K. M. , Dagher J. M. , Leuty G. M. , Harsch C. , Kim S. S. , Ngo Y. H. , Glavin N. R. , Berry R. J. , Durstock M. F. , Derosa P. A. , Roy A. K. , Heckman E. M. , Naik R. R.
Published: June 2018

An approach for printing micron-scale electronic devices built from two-dimensional materials is presented. Experimental phage display techniques and computational atomistic simulation approaches were used to identify a peptide molecule that effectively anchors to the basal plane surface of two-dimensional (2D) MoS2 to SiO2 surfaces. This peptide was suspended in water to develop an ink suitable for aerosol jet printing. The printed substrates were then dip coated with a suspension of liquid phase exfoliated 2D MoS2 particles. Strong adhesion of physically continuous lines of these particles was observed only on regions of the substrate patterned with the peptide-based ink, thereby enabling aerosol jet printing as a template for devices based on 2D materials. Graphene was also bound to SiO2 via a similar approach, but with a different peptide known from prior work to selectively adhere to the basal plane of graphene. Fundamental peptide-surface interactions for MoS2, graphene, and SiO2 were explored via simulation and experiment. This printing method is proposed as a route towards large-scale, low temperature patterning of 2D materials and devices. The electrical properties of continuous lines of MoS2 particles printed in a single pass of peptide ink printing were measured via transmission line measurements. The results indicate that this molecular attachment approach to printing possesses several advantages such as overcoming nozzle clogging due to nanomaterial aggregation, decoupling of particle size from any dimensions associated with the printer, and single-pass printing of electrically continuous films.
Composition and strain analysis of Si1-xGex core fiber with Raman spectroscopy
Authors: Wang Dongyang , Chen Na , Chen Zhenyi , Zhao Ziwen , Pang Fufei , Wang Tingyun
Published: June 2018

The fabrication and characterization of Si1-xGex core fiber have attracted much attention because of its great application potential in new optoelectronic devices. In this work, by assembling two semi-cylindrical monocrystalline Si and Ge rods into a silica tube, we present a fabrication method to draw Si1-xGex core silica clad fiber with graphite furnace. Raman spectra analysis reveals that in all regions of the core formed the Si1-xGex alloy. The optical microscopic photograph shows that in the core of a diameter of 36 μm distributed the bright and dark regions, where it was further proved by Raman spectroscopy that the bright regions are Ge-rich areas and the dark regions are rich in silicon. By recording the Raman spectra of consecutive regions, it was found that with the increase of Ge content (x<0.5) the peak intensity of Si-Ge mode obviously increases, similar to the intensity of Ge-Ge mode, while the peak intensity of Si-Si mode decreases. Then we made a quantitative analysis of the components and strain by mapping the Raman spectra of the fiber core. The experimental results show that the Ge content mainly distributes between 0.1 and 0.8, concentrating between 0.2 and 0.3, and the strain distribution on the surface is obtained at the same time.
Effect of initial time of forage supply on growth and rumen development in preweaning calves
Authors: Lin X. Y. , Wang Y. , Wang J. , Hou Q. L. , Hu Z. Y. , Shi K. R. , Yan Z. G. , Wang Z. H.
Published: June 2018

To determine the effects of the initial timing of forage supply on growth, ruminal fermentation parameters and rumen development in preweaning calves, 18 7-day-old Holstein calves of 42 ± 3 kg were randomly divided into three treatment groups. The dietary treatments were (1) milk and commercial starter diet (MS) control, (2) milk and starter diet supplemented with oat hay at 2 weeks (MSO2), and (3) milk and starter diet supplemented with oat hay at 6 weeks (MSO6). Starter feed and oat hay were provided ad libitum, and 2 L of milk was provided twice daily. Samples were collected at 64 days of age. Supplementing with hay increased the dry-matter intake; P < 0.05). The height, body length, heart girth and cannon bone circumference were similar among the three treatments (P > 0.05). The concentrations of serum glucose (P = 0.07) and β-hydroxybutyric acid; P < 0.05) were lower in the MSO6 group than in the MS and MSO2 groups. Rumination time was longer, and time spent on non-nutritive oral behaviour (such as e.g. licking surfaces, tongue rolling, wood-shaving consumption) was lower for hay-supplemented calves than for the control (P < 0.05). Although ruminal pH of hay-supplemented calves was significantly higher than that of the control, total rumen fluid volatile fatty acid concentrations were not significantly different among treatments. Calves in the MSO2 group had a smaller ratio of empty weight to slaughter weight (P < 0.05) and a larger total digestive tract weight (P < 0.05); the empty gastrointestinal tract weights were similar among the three treatments, suggesting that MSO2 calf weight gain may have resulted from intestinal chyme accumulation. Compared with the control, hay-supplemented calves had reduced rumen papilla width and epithelium thickness (P < 0.05), and no discernable plaque formation. Hay supplementation in the diet of preweaning calves improved the overall dry-matter intake, improved rumination, reduced non-nutritive oral behaviours, improved rumen pH, and ensured healthy rumen development; furthermore, productivity and rumen development were better in calves supplemented with hay from the second week.
On the Formation of Modern Chinese Pseudo-Possessive-Object Constructions
Authors: Long Haiping
Published: June 2018

Modern Chinese Pseudo-Possessive-Object Constructions (shortened as Modern Chinese PPO constructions; e.g. ta shuo le wo de haohua (他说了我的好话) ‘he has put in a good word for me’ and ta chi le wo de doufu (他吃了我的豆腐) ‘he has taken advantage of me’) are actually constructions displaying possessor-affectee syncretism. They derive from Early Modern Chinese Real-Possessive-Object constructions in bridging contexts, some examples being wo ye quande liewei daren de jiu (我也劝得列位大人的酒), ‘I also urged all the magistrates here to finish drinking your wine’ and shi nage zai jie wo de duan li (是那个在揭我的短哩) ‘who is uncovering my demerits’. Di-transitive constructions in Middle Chinese and Early Modern Chinese (e.g. Changxing! quan er yibei jiu (长星，劝尔一杯酒) ‘Comet! I urge you (to finish drinking) a cup of wine’ and shuru gan jie wu duanchu (竖儒敢揭吾短处) ‘how dare the Confucius scholar uncover my demerits’) have provided structural templates for the formation of Modern Chinese PPO constructions. They also have led to a condition in which there are more examples of a maleficiary Modern Chinese PPO construction than examples of a beneficiary Modern Chinese PPO construction (e.g. ta chi le wo de doufu (他吃了我的豆腐) ‘he has taken advantage of me’ vs. ta shuo le wo de haohua (他说了我的好话) ‘he has put in a good word for me’). The grammaticalization pathway can also explain the formation of other constructions including another Modern Chinese PPO construction (e.g. ta chi le wo de kui (他吃了我的亏) ‘he has suffered the loss caused by me’), a Modern Chinese pseudo-object construction (e.g. wo ganxie ni de haoxin (我感谢你的好心) ‘I thank you for your kindness’), and a Modern Chinese pseudo-modifier construction (e.g. wo pa le yi xiawu de shan (我爬了一下午的山) ‘I did mountain-climbing for the whole afternoon’).
From #[Je]F suis Charlie to #JeSuisCharlie
Authors: Hamlaoui Fatima , Roussarie Laurent
Published: June 2018

Je suis Charliewas used over 619.000 times in the two days that have followed the attack ofCharlie Hebdoand has regularly been taken up in both written and spoken forms since. A number of variants of this meme (i.e.Nous sommes tous (des) Charlie) have also emerged among French speakers. We argue that this is primarily related to the fact that the structure ofJe suis Charlieactually clashes with its meaning. Whereas its word order and default rightmost sentence stress are compatible either with an all-focus reading or a narrow focusing ofCharlie, the solidarity/empathy message it communicates suggests that its subject is narrowly focused. We propose that two strategies have emerged to solve this conflict: (i) various alternative forms have appeared that allow proper subject focusing and (ii) speakers have reinterpreted the original structure so as to pragmatically retrieve the (additive) focused nature of the subject.
Effects of processing conditions on microstructure and mechanical properties of equal-channel-angular-pressed titanium
Authors: Shaat M.
Published: June 2018

This review presents an investigation on effects of the processing conditions on the microstructural evolution and mechanical properties of commercial pure titanium processed by Equal Channel Angular Pressing (ECAP). An overview of ECAP processing is presented. A discussion on the microstructure evolution of ECAPed titanium emphasising effects of the ECAP-route type, processing temperature, number of ECAP passes, and mechanical/thermal treatments is presented. Moreover, the variations of the mechanical properties (yield strength, tensile strength, and ductility) of titanium as functions of the grain size are reported for the different conditions of ECAP processing. In addition, the best estimates of the Hall–Petch parameters for titanium processed by ECAP, ECAP followed by mechanical and/or thermal annealing are reported.
A Lichnerowicz estimate for the spectral gap of a sub-Laplacian
Authors: Berge Stine , Grong Erlend
Published: June 2018

For a second order operator on a compact manifold satisfying the strong Hörmander condition, we give a bound for the spectral gap analogous to the Lichnerowicz estimate for the Laplacian of a Riemannian manifold. We consider a wide class of such operators which includes horizontal lifts of the Laplacian on Riemannian submersions with minimal leaves.
Kato square root problem with unbounded leading coefficients
Authors: Escauriaza Luis , Hofmann Steve
Published: June 2018

We prove the Kato conjecture for elliptic operators,

L
=
−
∇
⋅

(
(

A

+

D

)
∇
 
)

L=-\nabla \cdot \left ((\mathbf A+\mathbf D)\nabla \ \right )

, with

A

\mathbf A

a complex measurable bounded coercive matrix and

D

\mathbf D

a measurable real-valued skew-symmetric matrix in

R

n

\mathbb {R}^n

with entries in

B
M
O
(

R

n

)

BMO(\mathbb {R}^n)

;  i.e., the domain of

L

\sqrt {L}\,

is the Sobolev space

H
˙

1

(

R

n

)

\dot H^1(\mathbb {R}^n)

in any dimension, with the estimate

‖

L

f

‖
2

≲
‖
∇
f

‖
2

\|\sqrt {L}\, f\|_2 \lesssim \| \nabla f\|_2

.
Uniform symbolic topologies in abelian extensions
Authors: Huneke Craig , Katz Daniel
Published: June 2018

In this paper we prove that, under mild conditions, an equicharacteristic integrally closed domain which is a finite abelian extension of a regular domain has the uniform symbolic topology property.
Doing science in difficult socioeconomic circumstances
Authors: Karasmanis Eva P.
Published: June 2018

Doing scientific research can be a challenging, but creative and rewarding career. However, the challenge of doing research is orders of magnitude more difficult for scientists lacking access to the necessary resources. Resource-scarce environments are quite common worldwide and are highly contingent on the financial and social climate of one’s location. Through the experiences of four scientists, this Perspective explores the challenges associated with doing research in disadvantaged socioeconomic circumstances. By reflecting on the humble beginnings of these scientists, we examine the motivation to stay in or leave one’s home country, and how hardships can be leveraged to cultivate passionate and productive researchers.
Review of applications of high-throughput sequencing in personalized medicine: barriers and facilitators of future progress in research and clinical application
Authors: Lightbody Gaye , Haberland Valeriia , Browne Fiona , Taggart Laura , Zheng Huiru , Parkes Eileen , Blayney Jaine K
Published: June 2018

There has been an exponential growth in the performance and output of sequencing technologies (omics data) with full genome sequencing now producing gigabases of reads on a daily basis. These data may hold the promise of personalized medicine, leading to routinely available sequencing tests that can guide patient treatment decisions. In the era of high-throughput sequencing (HTS), computational considerations, data governance and clinical translation are the greatest rate-limiting steps. To ensure that the analysis, management and interpretation of such extensive omics data is exploited to its full potential, key factors, including sample sourcing, technology selection and computational expertise and resources, need to be considered, leading to an integrated set of high-performance tools and systems. This article provides an up-to-date overview of the evolution of HTS and the accompanying tools, infrastructure and data management approaches that are emerging in this space, which, if used within in a multidisciplinary context, may ultimately facilitate the development of personalized medicine.
ImmunomeBrowser: a tool to aggregate and visualize complex and heterogeneous epitopes in reference proteins
Authors: Dhanda Sandeep Kumar , Vita Randi , Ha Brendan , Grifoni Alba , Peters Bjoern , Sette Alessandro
Published: June 2018

Motivation

Datasets that are derived from different studies (e.g. MHC ligand elution, MHC binding, B/T cell epitope screening etc.) often vary in terms of experimental approaches, sizes of peptides tested, including partial and or nested overlapping peptides and in the number of donors tested.

Results

We present a customized application of the Immune Epitope Database’s ImmunomeBrowser tool, which can be used to effectively aggregate and visualize heterogeneous immunological data. User provided peptide sets and associated response data is mapped to a user-provided protein reference sequence. The output consists of tables and figures representing the aggregated data represented by a Response Frequency score and associated estimated confidence interval. This allows the user to visualizing regions associated with dominant responses and their boundaries. The results are presented both as a user interactive javascript based web interface and a tabular format in a selected reference sequence.

Availability and implementation

The ‘ImmunomeBrowser’ has been a longstanding feature of the IEDB (http://www.iedb.org). The present application extends the use of this tool to work with user-provided datasets, rather than the output of IEDB queries. This new server version of the ImmunomeBrowser is freely accessible at http://tools.iedb.org/immunomebrowser/.
Partitioned time-stepping scheme for an MHD system with temperature-dependent coefficients
Authors: Ravindran S S
Published: June 2018

In this paper, a partitioned time-stepping scheme for transient electromagnetically and thermally driven flow is analysed. The flow is modeled by coupled evolutionary magneto-hydrodynamic (MHD) equations with temperature-dependent coefficients. The partitioned scheme requires solving only one uncoupled MHD equation and one heat transfer equation per time step. It is based on Crank–Nicolson discretization in time and extrapolated treatment of the coupling and nonlinear terms such that skew-symmetry properties of the nonlinear terms are preserved. We prove that the proposed time-stepping scheme is unconditionally stable and derive error estimates for the fully discretized scheme using finite element spatial discretization in suitable norms. Numerical examples are presented that illustrate the accuracy and efficiency of the scheme.
The harmonic virtual element method: stabilization and exponential convergence for the Laplace problem on polygonal domains
Authors: Chernov Alexey , Mascotto Lorenzo
Published: June 2018

We introduce the harmonic virtual element method (VEM) (harmonic VEM), a modification of the VEM (Beirão da Veiga et al. (2013) Basic principles of virtual element methods. Math. Models Methods Appl. Sci., 23, 199–214.) for the approximation of the two-dimensional Laplace equation using polygonal meshes. The main difference between the harmonic VEM and the VEM is that in the former method only boundary degrees of freedom are employed. Such degrees of freedom suffice for the construction of a proper energy projector on (piecewise harmonic) polynomial spaces. The harmonic VEM can also be regarded as an ‘$H^1$-conformisation’ of the Trefftz discontinuous Galerkin-finite element method (TDG-FEM) (Hiptmair et al. (2014) Approximation by harmonic polynomials in starshaped domains and exponential convergence of Trefftz hp-DGFEM. ESAIM Math. Model. Numer. Anal., 48, 727–752.). We address the stabilization of the proposed method and develop an hp version of harmonic VEM for the Laplace equation on polygonal domains. As in TDG-FEM, the asymptotic convergence rate of harmonic VEM is exponential and reaches order $\mathscr{O}(\exp (-b\sqrt [2]{N}))$, where $N$ is the number of degrees of freedom. This result overperforms its counterparts in the framework of hp FEM (Schwab, C. (1998)p- and hp-Finite Element Methods: Theory and Applications in Solid and Fluid Mechanics. Clarendon Press Oxford.) and hp VEM (Beirão da Veiga et al. (2018) Exponential convergence of the hp virtual element method with corner singularity. Numer. Math., 138, 581–613.), where the asymptotic rate of convergence is of order $\mathscr{O}(\exp(-b\sqrt [3]{N}))$.
Contractions of Representations and Algebraic Families of Harish-Chandra Modules
Authors: Bernstein Joseph , Higson Nigel , Subag Eyal
Published: June 2018

We examine from an algebraic point of view some families of unitary group representations that arise in mathematical physics and are associated to contraction families of Lie groups. The contraction families of groups relate different real forms of a reductive group and are continuously parametrized, but the unitary representations are defined over a parameter subspace that includes both discrete and continuous parts. Both finite- and infinite-dimensional representations can occur, even within the same family. We shall study the simplest nontrivial examples and use the concepts of algebraic families of Harish-Chandra pairs and Harish-Chandra modules, introduced in a previous paper, together with the Jantzen filtration, to construct these families of unitary representations algebraically.
Algebraic Families of Harish-Chandra Pairs
Authors: Bernstein Joseph , Higson Nigel , Subag Eyal
Published: June 2018

Mathematical physicists have studied degenerations of Lie groups and their representations, which they call contractions. In this paper we study these contractions, and also other families, within the framework of algebraic families of Harish-Chandra modules. We construct a family that incorporates both a real reductive group and its compact form, separate parts of which have been studied individually as contractions. We give a complete classification of generically irreducible families of Harish-Chandra modules in the case of the family associated to $SL(2,\mathbb{R})$.
Information Criterion for Nonparametric Model-Assisted Survey Estimators
Authors: James Addison , Xue Lan , Lesser Virginia
Published: June 2018

Nonparametric model-assisted estimators have been proposed to improve estimates of finite population parameters. Flexible nonparametric models provide more reliable estimators when a parametric model is misspecified. In this article, we propose an information criterion to select appropriate auxiliary variables to use in an additive model-assisted method. We approximate the additive nonparametric components using polynomial splines and extend the Bayesian Information Criterion (BIC) for finite populations. By removing irrelevant auxiliary variables, our method reduces model complexity and decreases estimator variance. We establish that the proposed BIC is asymptotically consistent in selecting the important explanatory variables when the true model is additive without interactions, a result supported by our numerical study. Our proposed method is easier to implement and better justified theoretically than the existing method proposed in the literature.
Impact of Powdered Vancomycin on Preventing Surgical Site Infections in Neurosurgery: A Systematic Review and Meta-analysis
Authors: Texakalidis Pavlos , Lu Victor M , Yolcu Yagiz , Kerezoudis Panagiotis , Alvi Mohammed Ali , Parney Ian F , Fogelson Jeremy L , Bydon Mohamad
Published: June 2018

BACKGROUND

Surgical site infections (SSIs) after spine and brain surgery present a major burden to patients and hospitals by increasing morbidity, mortality, and healthcare costs.

OBJECTIVE

To review available literature investigating the role of intrawound powdered vancomycin against SSIs after neurosurgical operations.

METHODS

All randomized and observational English language studies of intrawound powdered vancomycin use in spinal and cranial surgery were included and analyzed using random-effects modeling.

RESULTS

In spine surgery (25 studies with 16 369 patients), patients in the vancomycin group had a significantly lower risk for any SSI (odds ratio [OR]: 0.41; 95% confidence interval [CI]: 0.30-0.57; P < .001; I2 = 47%). However, when separate analyses were conducted for superficial and deep SSIs, a significant difference was found only for deep (OR: 0.31; 95% CI: 0.22-0.45; P < .001; I2 = 29%). Subgroup analyses for different vancomycin powder dosages (1 g vs 2 g vs composite dose) did not point to any dose-related effect of vancomycin. In cranial surgery (6 studies with 1777 patients), use of vancomycin was associated with a significantly lower risk for SSIs (OR: 0.33; 95% CI: 0.18-0.60; P = .0003; I2 = 45%). In meta-regression analysis, trial-level variability of diabetes had no influence on the association of vancomycin powder use with SSIs.

CONCLUSION

Use of vancomycin powder in spinal and cranial surgery might be protective against SSIs, especially against deep SSIs. No dose-related effect of vancomycin powder was identified. However, caution is needed in the clinical interpretation of these results, owing to the observational design of the included studies in this meta-analysis.
Effectiveness of Nontarped Broadcast Fumigation and Root Removal on Root Lesion Nematode and Fusarium and Pythium Species in a Red Raspberry System
Authors: DeVetter Lisa W. , Watkinson Sean , Zasada Inga A. , Weiland Jerry E. , Hesse Cedar , Walters Thomas W.
Published: June 2018

Improved methods for the management of soil-borne pathogens are needed in the raspberry production system in the Pacific Northwest. A multiyear experiment was conducted in a commercial raspberry field in northwest Washington with the following objectives: (i) to determine if the standard industry fumigation treatment of nontarped broadcast application of 1,3-dichloropropene/chloropicrin (Telone C-35) is effective against Pratylenchus penetrans and Pythium and Fusarium species; (ii) to determine if root removal prior to nontarped broadcast fumigation with Telone C-35 improves management of P. penetrans and Fusarium and Pythium species; and (iii) to identify microbes that have the potential to be soil-borne pathogens through microbial community analysis. Fumigation alone briefly reduced population densities of P. penetrans but was ineffective at reducing existing, pretreatment populations of Fusarium and Pythium. However, populations of these two genera were lower in fumigated than in nonfumigated plots for at least 6 months after fumigation. Root removal did not enhance fumigant efficacy under the conditions of the experiment. Ilyonectria (Cylindrocarpon) was found to be more dominant in the fungal community of nonfumigated roots and rhizosphere soil compared with fumigated. These results demonstrate that P. penetrans, Fusarium, and Pythium rapidly rebound after nontarped broadcast fumigation in raspberry with the industry standard Telone C-35.
Attention Deficit-Hyperactivity Disorder Group Visits Improve Parental Emotional Health and Perceptions of Child Behavior
Authors: Bauer Nerissa S. , Sullivan Paula D. , Szczepaniak Dorota , Stelzner Sarah M. , Pottenger Amy , Ofner Susan , Downs Stephen M. , Carroll Aaron E.
Published: June 2018

Objective:

Group visits (GVs) are a promising intervention, but more work is needed to establish intervention effects. The objective was to evaluate the effectiveness of GVs and compare them with individual visits (INDs) for chronic care of attention deficit-hyperactivity disorder (ADHD).

Methods:

Caregivers and children (6–12 yrs) with ADHD participated in a comparative effectiveness trial from April 2014 to June 2015. Families were offered ADHD follow-up every 3 months as GVs versus INDs. Outcomes included ADHD core symptoms, child functioning at home, quality of life, perceived social support, and ADHD-related parenting challenges. Change scores from baseline to the study end were examined for parent and child outcomes within and between treatment conditions.

Results:

Ninety-one children from 84 families participated. Eighteen families withdrew or were lost to follow-up. GV families attended more visits over 12 months, had significant improvement in mean parental emotional health (p = 0.04), and had a greater decrease in challenges related to misbehavior compared with IND families (p < 0.03). GV families experienced significant improvements in child functioning at home (p = 0.01) and reported more time for themselves, other siblings, and routine household activities (p < 0.01). Children receiving care as INDs reported a significant drop in mean emotional health. There were no significant changes in other outcomes.

Conclusion:

Families participating in GVs experienced multiple improvements related to family functioning and attended more follow-up visits. Findings confirm the effectiveness of the GV intervention in delivering critical parenting support as part of ADHD management.
Maternal Anxiety and Separation Anxiety in Children Aged Between 3 and 6 Years: The Mediating Role of Parenting Style
Authors: Orgilés Mireia , Penosa Patricia , Morales Alexandra , Fernández-Martínez Iván , Espada José P.
Published: June 2018

Objective:

Maternal anxiety is known to be associated with childhood separation anxiety. However, there is little research on the mediating factors of this relationship, despite the possible consequences separation anxiety might have for children's development and autonomy. The objective of this study was to analyze the possible mediating effects of 4 parenting styles (overprotective, assertive, punitive, and inhibited) on the relationship between maternal anxiety and child separation anxiety.

Methods:

Participants were 235 mothers with children aged 3 to 6 years, recruited from 6 preschools in the southeast of Spain. Maternal trait anxiety, maternal parenting style, and child separation anxiety were evaluated.

Results:

A parallel multiple-mediation analysis revealed that the overprotective parenting style was a significant mediator of the relationship between maternal trait anxiety and child separation anxiety. In addition, mothers with higher trait anxiety scores exhibited a greater likelihood of using an overprotective, punitive, or less assertive parenting style. Younger mothers were more likely to use an overprotective parenting style, and compared with girls, boys were more exposed to the assertive style.

Conclusion:

This study provides initial evidence that parenting style acts as a mediator of the relationship between maternal anxiety and child separation anxiety.
Sustained Benefit After Treatment of Acne Vulgaris Using Only a Novel Combination of Long-Pulsed and Q-Switched 1064-nm Nd:YAG Lasers
Authors: Bakus Abnoeal D. , Yaghmai Dina , Massa Mary C. , Garden Benjamin C. , Garden Jerome M.
Published: June 2018

BACKGROUND

Acne vulgaris remains a challenging disease to treat in many patients. Traditional therapies may have limited successes with potential side effects. Laser and light energy devices may offer a desirable alternative.

OBJECTIVE

To evaluate the effectiveness and safety in using a combination laser approach with both long-pulsed (LP) and Q-switched (QS) Nd:YAG lasers in the treatment of active acne.

METHODS

Twenty patients with moderate to severe inflammatory acne were treated with LP YAG laser followed immediately with QS YAG laser. Patients received at least 8 treatments. Follow-up evaluation occurred at a minimum of 12 months. Pre- and post-treatment photographs were graded by blinded physicians. All topical acne medications and oral antibiotics were discontinued throughout the therapy and follow-up period.

RESULTS

There was a 81% reduction in acne lesions, with 60% of patients having 90% or greater reduction. Overall appearance was graded at 84% improvement at follow-up. Follow-up occurred at a mean of 22.7 months after completion of therapy. Aside from transient erythema, there were no other adverse effects.

CONCLUSION

Active acne can be treated successfully with a combination of LP and QS YAG lasers with patients remaining off acne medications throughout laser therapy and the follow-up period.
CAPILLARY NETWORK ALTERATIONS IN X-LINKED RETINOSCHISIS IMAGED ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY
Authors: Romano Francesco , Arrigo Alessandro , Ch'ng Soon Wai , Battaglia Parodi Maurizio , Manitto Maria Pia , Martina Elisabetta , Bandello Francesco , Stanga Paulo E.
Published: June 2018

Purpose:

To assess foveal and parafoveal vasculature at the superficial capillary plexus, deep capillary plexus, and choriocapillaris of patients with X-linked retinoschisis by means of optical coherence tomography angiography.

Methods:

Six patients with X-linked retinoschisis (12 eyes) and seven healthy controls (14 eyes) were recruited and underwent complete ophthalmologic examination, including best-corrected visual acuity, dilated fundoscopy, and 3 × 3-mm optical coherence tomography angiography macular scans (DRI OCT Triton; Topcon Corp). After segmentation and quality review, optical coherence tomography angiography slabs were imported into ImageJ 1.50 (NIH; Bethesda) and digitally binarized. Quantification of vessel density was performed after foveal avascular zone area measurement and exclusion. Patients were additionally divided into “responders” and “nonresponders” to dorzolamide therapy.

Results:

Foveal avascular zone area resulted markedly enlarged at the deep capillary plexus (P < 0.001), particularly in nonresponders. Moreover, patients disclosed a significant deep capillary plexus rarefaction, when compared with controls (P: 0.04); however, a subanalysis revealed that this damage was limited to the fovea (P: 0.006). Finally, the enlargement of foveal avascular zone area positively correlated with a decline in best-corrected visual acuity (P: 0.01).

Conclusion:

Prominent foveal vascular impairment is detectable in the deep capillary plexus of patients with X-linked retinoschisis. Our results correlate with functional outcomes, suggesting a possible vascular role in X-linked retinoschisis clinical manifestations.
Sex Differences in Acute Myocardial Infarction Hospital Management and Outcomes
Authors: Romero Tomás , Greenwood Kristina L. , Glaser Dale
Published: June 2018

Background:

Acute myocardial infarction (AMI) sex disparities in management and outcomes have long been attributed to multiple factors, although questions regarding their relevance have not been fully addressed.

Objective:

The aim of this study was to identify current factors associated with sex-related AMI management and outcomes disparities in hospitals with comparable quality care standards.

Methods:

This is a cross-sectional study of 299 women and 540 men with AMI discharged in 2013 from 3 southern California hospitals with tertiary cardiac care. Outcomes (adjusted by demographic/clinical variables using multiple logistic regression) included mortality (in-hospital, 30 days), 30-day readmissions, invasive/revascularization procedures, and quality medication performance measures (aspirin, statins/antilipids, β-blockers, angiotensin-converting enzyme inhibitors, <90-minute door-balloon time).

Results:

Performance was similar to the top 10% National Inpatient Quality AMI Measures. Women had similar mortality, 30-day readmission rates, and performance on medication quality measures compared with men; readmissions were higher in patients with County Services/Medicaid or no medical insurance regardless of sex. Women had similar cardiac catheterization and ST-segment elevation myocardial infarction percutaneous coronary intervention rates but significantly less percutaneous coronary intervention for non–ST-segment elevation myocardial infarction (39.1% vs 52.1%, P = .008) and coronary artery bypass graft (6.7% vs 14.1%, P < .001) than men.

Conclusions:

Women with AMI had similar early mortality, 30-day readmissions and quality performance measures compared with men across hospitals with current quality care standards. Type of medical insurance influenced readmission rates for both sexes. Sex disparities in coronary revascularization procedures were likely determined by differences in AMI type and coronary disease vascular expression.
The Effectiveness of Function-Focused Care Interventions in Nursing Homes: A Systematic Review
Authors: LEE Su Jung , KIM Mi So , JUNG You Jin , CHANG Sung Ok
Published: June 2018

Background:

Since the Omnibus Budget and Reconciliation Act was passed in South Korea in 1987, function-focused care (FFC) has been used in long-term care to achieve the highest possible levels of self-care and independence for older adults. However, many perceive nursing home residents with cognitive function impairments as having little restorative potential.

Purpose:

The purpose of this review is to report on evidence and strategies relating to FFC interventions in nursing home settings and to summarize the effects of FFC on the functional abilities of resident subgroups.

Methods:

A literature review using EMBASE, MEDLINE, and Cumulative Index to Nursing and Allied Health Literature was conducted for articles published between January 1, 2000, and February 20, 2016. Twenty-two eligible studies were identified. Relevant data were extracted, and the results were synthesized into an integrated literature review. Study quality was appraised using the Cochrane Risk of Bias tool and the Risk of Bias Assessment tool for Non-randomized Studies.

Results:

This review included 22 trials that were of moderate to high quality. Our systematic review confirmed the FFC interventions as integrated and dedicated processes; the five key strategies underpinning effective FFC interventions; and the effectiveness of FFC interventions on physical, psychosocial, and cognitive functions. The five key strategies underpinning FFC interventions included interactive learning for caregivers, the content of learning programs for caregivers, residents’ preferences and interests, optimizing approaches according to residents’ functional status, and the conceptual frameworks of FFC interventions. Most of the studies (n = 15) evaluated psychosocial functions and found significant improvements in aspects such as mood, affect, and behavioral problems. Likewise, the 13 studies assessing physical function found significant improvements in effectiveness in aspects such as movement, balance, and activities of daily living. Only four studies looked at cognitive function effectiveness, using measures such as place finding, verbal use, and memory.

Conclusions/Implications for Practice:

Our review found scientific evidence that FFC interventions improve functional abilities across various levels of cognitive function in nursing homes. Nursing homes may employ effective strategies to maximize the effects of FFC interventions and use educational materials to teach caregivers to implement FFC interventions competently.
Emergence Delirium in Children: Review and Rationale for the Use of Dexmedetomidine for Prevention
Authors: Whitman Tina M.
Published: June 2018

Pediatric emergence delirium is a problematic condition affecting children emerging from general anesthesia. Young children specifically have an increased probability of developing this condition; risk factors such as gender, surgical procedure, pain, and/or anesthetic technique pose an increased susceptibility to emergence delirium. Dexmedetomidine, an alpha-2 agonist, has been shown to be effective in reducing the incidence of pediatric emergence delirium in a variety of administrative methods. This article presents a review of emergence delirium and rationale for its prevention with dexmedetomidine. There are presently many pharmacological methods of treating and avoiding emergence delirium. However, dexmedetomidine has been shown to be a safe and effective choice above the current pharmacological alternatives in the pediatric population.
Building a Pediatric Perioperative Surgical Home
Authors: Robinson Renee , Schriefer Jan , Gloff Marjorie , Michels Julie , Webber Audra , Hilt Suzanne , Sanders James , Herman Emily
Published: June 2018

Introduction

The pediatric perioperative surgical home (PPSH) is a population health management model designed to provide a seamless experience for children and their families undergoing surgical procedures. The purpose of this quality improvement project is to evaluate the feasibility and utility of implementing a PPSH at an academic medical center.

Method

A multidisciplinary team was formed, composed of representatives from nursing, surgery, anesthesiology, and perioperative medicine. This group developed a comprehensive preoperative screening tool designed for early identification of patient barriers before elective surgery.

The screening tool was developed with input from multiple pediatric subspecialists. At the initial surgical visit, patients and families are encouraged to complete this screening tool. The screening tool was piloted to 74 patients (46 completed) in a pediatric orthopedic clinic for an 8-month period. Existing tools in the electronic medical record system were identified to assist with care coordination perioperatively.

Result

In comparing our baseline period (2016, n = 174) with the early implementation phase of our PPSH (2017, n = 188), unplanned readmission rates decreased from 4.0% to 2% (p = .011), and surgical site infections decreased from 3.5% to 2.3% (p = .002), whereas unplanned return to operating room and average length of stay remained the same.

Conclusion

Information obtained within a PPSH informs the entire team of important factors that could influence perioperative care. A PPSH serves to make the health care team more efficient and may also be associated with a reduction in complications, cost, and time spent in the hospital.