bluuebunny/crossref_metadata_2025 huggingface dataset:
Permeability measurement and control for epoxy composites
Authors: Chang Tsun-Hsu , Tsai Cheng-Hung , Wong Wei-Syuan , Chen Yen-Ren , Chao Hsien-Wen
Published: August 2017

The coupling of the electric and magnetic fields leads to a strong interplay in materials' permittivity and permeability. Here, we proposed a specially designed cavity, called the mu cavity. The mu cavity, consisting of a mushroom structure inside a cylindrical resonator, is exclusively sensitive to permeability, but not to permittivity. It decouples materials' electromagnetic properties and allows an accurate measurement of the permeability. With the help of an epsilon cavity, these two cavities jointly determine the complex permeability and permittivity of the materials at microwave frequencies. Homemade epoxy-based composite materials were prepared and tested. Measurement and manipulation of the permeability and permittivity of the epoxy composites will be shown. The results will be compared with the effective medium theories.
A review on wax printed microfluidic paper-based devices for international health
Authors: Altundemir S. , Uguz A. K. , Ulgen K.
Published: August 2017

Paper-based microfluidics has attracted attention for the last ten years due to its advantages such as low sample volume requirement, ease of use, portability, high sensitivity, and no necessity to well-equipped laboratory equipment and well-trained manpower. These characteristics have made paper platforms a promising alternative for a variety of applications such as clinical diagnosis and quantitative analysis of chemical and biological substances. Among the wide range of fabrication methods for microfluidic paper-based analytical devices (μPADs), the wax printing method is suitable for high throughput production and requires only a commercial printer and a heating source to fabricate complex two or three-dimensional structures for multipurpose systems. μPADs can be used by anyone for in situ diagnosis and analysis; therefore, wax printed μPADs are promising especially in resource limited environments where people cannot get sensitive and fast diagnosis of their serious health problems and where food, water, and related products are not able to be screened for toxic elements. This review paper is focused on the applications of paper-based microfluidic devices fabricated by the wax printing technique and used for international health. Besides presenting the current limitations and advantages, the future directions of this technology including the commercial aspects are discussed. As a conclusion, the wax printing technology continues to overcome the current limitations and to be one of the promising fabrication techniques. In the near future, with the increase of the current interest of the industrial companies on the paper-based technology, the wax-printed paper-based platforms are expected to take place especially in the healthcare industry.
Comparison between conventional and inverted solar cells using open circuit voltage decay transients
Authors: Verma Upkar K. , Kumar Sunil , Mohapatra Y. N.
Published: August 2017

In the development of new structures for solar cells, it has become important to extract the true ideality factor of a diode, disentangling it from other loss mechanisms in the device. We use the open circuit voltage decay (OCVD) transient to obtain ideality factors and isolate the internal loss mechanisms in P3HT:PCBM bulk heterojunction solar cells. We compare two different structures using OCVD transients over more than six orders in timescale. The equivalent circuit parameters of diodes can be reliably extracted from such decays. Specifically, the numerical solution of the transient allows the determination of the diode ideality factor, and the saturation leakage current. In addition, this technique makes it possible to determine the diode current in the presence of excess carriers under photo irradiance, and hence, the light induced recombination current and shunt resistance can be separately extracted. We compare the decay transients of an efficient device with a leaky device and demonstrate that the diode current changes in the same manner in both the cases. We study in detail the intensity power-law dependence of the recombination current that controls the decay transient and observe that it increases significantly faster in leaky devices with light intensity.
Correlation consistent basis sets for actinides. II. The atoms Ac and Np–Lr
Authors: Feng Rulin , Peterson Kirk A.
Published: August 2017

New correlation consistent basis sets optimized using the all-electron third-order Douglas-Kroll-Hess (DKH3) scalar relativistic Hamiltonian are reported for the actinide elements Ac and Np through Lr. These complete the series of sets reported previously for Th–U [K. A. Peterson, J. Chem. Phys. 142, 074105 (2015); M. Vasiliu et al., J. Phys. Chem. A 119, 11422 (2015)]. The new sets range in size from double- to quadruple-zeta and encompass both those optimized for valence (6s6p5f7s6d) and outer-core electron correlations (valence + 5s5p5d). The final sets have been contracted for both the DKH3 and eXact 2-component (X2C) Hamiltonians, yielding cc-pVnZ-DK3/cc-pVnZ-X2C sets for valence correlation and cc-pwCVnZ-DK3/cc-pwCVnZ-X2C sets for outer-core correlation (n = D, T, Q in each case). In order to test the effectiveness of the new basis sets, both atomic and molecular benchmark calculations have been carried out. In the first case, the first three atomic ionization potentials (IPs) of all the actinide elements Ac–Lr have been calculated using the Feller-Peterson-Dixon (FPD) composite approach, primarily with the multireference configuration interaction (MRCI) method. Excellent convergence towards the respective complete basis set (CBS) limits is achieved with the new sets, leading to good agreement with experiment, where these exist, after accurately accounting for spin-orbit effects using the 4-component Dirac-Hartree-Fock method. For a molecular test, the IP and atomization energy (AE) of PuO2 have been calculated also using the FPD method but using a coupled cluster approach with spin-orbit coupling accounted for using the 4-component MRCI. The present calculations yield an IP0 for PuO2 of 159.8 kcal/mol, which is in excellent agreement with the experimental electron transfer bracketing value of 162 ± 3 kcal/mol. Likewise, the calculated 0 K AE of 305.6 kcal/mol is in very good agreement with the currently accepted experimental value of 303.1 ± 5 kcal/mol. The ground state of PuO2 is predicted to be the Σ0g+5 state.
The dynamics of nucleation and growth of a particle in the ternary alloy melt with anisotropic surface tension
Authors: Chen Ming-Wen , Li Lin-Yan , Guo Hui-Min
Published: August 2017

The dynamics of nucleation and growth of a particle affected by anisotropic surface tension in the ternary alloy melt is studied. The uniformly valid asymptotic solution for temperature field, concentration field, and interface evolution of nucleation and particle growth is obtained by means of the multiple variable expansion method. The asymptotic solution reveals the critical radius of nucleation in the ternary alloy melt and an inward melting mechanism of the particle induced by the anisotropic effect of surface tension. The critical radius of nucleation is dependent on isotropic surface tension, temperature undercooling, and constitutional undercooling in the ternary alloy melt, and the solute diffusion melt decreases the critical radius of nucleation. Immediately after a nucleus forms in the initial stage of solidification, the anisotropic effect of surface tension makes some parts of its interface grow inward while some parts grow outward. Until the inward melting attains a certain distance (which is defined as “the melting depth”), these parts of interface start to grow outward with other parts. The interface of the particle evolves into an ear-like deformation, whose inner diameter may be less than two times the critical radius of nucleation within a short time in the initial stage of solidification. The solute diffusion in the ternary alloy melt decreases the effect of anisotropic surface tension on the interface deformation.
Numerical investigations of electrothermally actuated moving contact line dynamics: Effect of property contrasts
Authors: Kunti Golak , Bhattacharya Anandaroop , Chakraborty Suman
Published: August 2017

This article reports interfacial electro-thermo-chemical-hydrodynamics of binary fluids with contrasting viscosity, thermal conductivity, and electrical conductivity of fluids under AC electrokinetics, called alternating current electrothermal (ACET) mechanism, over wetted substrates. The interfacial kinetics of the two phases are modulated by the coupled influence of electrothermal, viscous, and capillary forces. Numerical investigations of contact line dynamics reveal that at low viscosity of displaced fluid, viscous drag force significantly reduces leading to faster progression of the contact line. Larger viscous drag force at higher viscosity of the displaced fluid resists the interface motion to travel along the capillary. ACET forces are the direct consequences of the thermal and electric fields. For low thermal conductivity of the displaced fluid, the temperature gradient becomes much stronger leading to higher ACET forces and contact line velocity. Below a threshold limit of thermal conductivity, stronger electrothermal forces cause misbalance between contact line velocity and bulk fluid velocity, which, in turn, trigger an interesting phenomena of interface breaking. Mismatch in electrical conductivity generates electrical stresses across the interface that deforms the interface profile and causes boosting impact across the interface leading to an increase in contact line velocity. The net force across the interface changes the direction depending on the deviation of electrical conductivity ratio from unity. Finally, we observe that larger channel height and wider electrode spacing decrease the net force on the bulk fluid and contact line velocity.
Dissociative recombination of HCl+
Authors: Larson Åsa , Fonseca dos Santos Samantha , E. Orel Ann
Published: August 2017

The dissociative recombination of HCl+, including both the direct and indirect mechanisms, is studied. For the direct process, the relevant electronic states are calculated ab initio by combining electron scattering calculations to obtain resonance positions and autoionization widths with multi-reference configuration interaction calculations of the ion and Rydberg states. The cross section for the direct dissociation along electronic resonant states is computed by solution of the time-dependent Schrödinger equation. For the indirect process, an upper bound value for the cross section is obtained using a vibrational frame transformation of the elements of the scattering matrix at energies just above the ionization threshold. Vibrational excitations of the ionic core from the ground vibrational state, v = 0, to the first three excited vibrational states, v = 1, v = 2, and  v = 3, are considered. Autoionization is neglected and the effect of the spin-orbit splitting of the ionic potential energy upon the indirect dissociative recombination cross section is considered. The calculated cross sections are compared to measurements.
Efficient parameterization of cardiac action potential models using a genetic algorithm
Authors: Cairns Darby I. , Fenton Flavio H. , Cherry E. M.
Published: August 2017

Finding appropriate values for parameters in mathematical models of cardiac cells is a challenging task. Here, we show that it is possible to obtain good parameterizations in as little as 30–40 s when as many as 27 parameters are fit simultaneously using a genetic algorithm and two flexible phenomenological models of cardiac action potentials. We demonstrate how our implementation works by considering cases of “model recovery” in which we attempt to find parameter values that match model-derived action potential data from several cycle lengths. We assess performance by evaluating the parameter values obtained, action potentials at fit and non-fit cycle lengths, and bifurcation plots for fidelity to the truth as well as consistency across different runs of the algorithm. We also fit the models to action potentials recorded experimentally using microelectrodes and analyze performance. We find that our implementation can efficiently obtain model parameterizations that are in good agreement with the dynamics exhibited by the underlying systems that are included in the fitting process. However, the parameter values obtained in good parameterizations can exhibit a significant amount of variability, raising issues of parameter identifiability and sensitivity. Along similar lines, we also find that the two models differ in terms of the ease of obtaining parameterizations that reproduce model dynamics accurately, most likely reflecting different levels of parameter identifiability for the two models.
Influence of H2 and D2 plasmas on the work function of caesiated materials
Authors: Friedl R. , Fantz U.
Published: August 2017

Caesium-covered surfaces are used in negative hydrogen ion sources as a low work function converter for H–/D– surface production. The work function χ of the converter surface is one of the key parameters determining the performance of the ion source. Under idealized conditions, pure bulk Cs has 2.14 eV. However, residual gases at ion source background pressures of 10−7–10−6 mbar and the plasma surface interaction with the hydrogen discharge in front of the caesiated surface dynamically affect the actual surface work function. Necessary fundamental investigations on the resulting χ are performed at a dedicated laboratory experiment. Under the vacuum conditions of ion sources, the incorporation of impurities into the Cs layer leads to very stable Cs compounds. The result is a minimal work function of χvac ≈ 2.75 eV for Cs evaporation rates of up to 10 mg/h independent of substrate material and surface temperature (up to 260 °C). Moreover, a distinct degradation behavior can be observed in the absence of a Cs flux onto the surface leading to a deterioration of the work function by about 0.1 eV/h. However, in a hydrogen discharge with plasma parameters close to those of ion sources, fluxes of reactive hydrogen species and VUV photons impact on the surface which reduces the work function of the caesiated substrate down to about 2.6 eV even without Cs supply. Establishing a Cs flux onto the surface with ΓCs ≈ 1017 m−2 s−1 further enhances the work function obtaining values around 2.1 eV, which can be maintained stable for several hours of plasma exposure. Hence, Cs layers with work functions close to that of pure bulk Cs can be achieved for both H2 and D2 plasmas. Isotopic differences can be neglected within the measurement accuracy of about 0.1 eV due to comparable plasma parameters. Furthermore, after shutting down the Cs evaporation, continuing plasma exposure helps against degradation of the Cs layer resulting in a constant low work function for at least 1 h.
A bio-inspired method for direct measurement of local wall shear rates with micrometer localization using the multimeric protein von Willebrand factor as sensor molecule
Authors: Bonazza Klaus , Scheichl Bernhard , Frank Johannes , Rottensteiner Hanspeter , Schrenk Gerald , Friedbacher Gernot , Turecek Peter L. , Scheiflinger Friedrich , Allmaier Günter
Published: August 2017

Wall shear rates are critical for a broad variety of fluidic phenomena and are taken into account in nearly every experimental or simulation study. Generally, shear rates are not observable directly but rather derived from other parameters such as pressure and flow, often assuming somehow idealized systems. However, there is a biological system which is able to constantly measure the wall shear as a part of a regulatory circuit: The blood circulation system takes advantage of shear rate sensor (protein)molecules (multimeric forms of von Willebrand Factor, VWF), which are dissolved in the blood plasma and dramatically change their conformation under shear conditions. The conformational changes are accompanied by several functional variations and therefore interplay with the regulation of the coagulation system. In this study, we use a recombinantly produced and therefore well-defined multimeric form of VWF as a sensor which directly responds to shear rates. Shear rates, up to 32.000 s−1, were obtained using a kind of micro-plate-to-plate rheometer capable of adsorbing shear-stretched VWF oligomeric molecules on a surface to conserve their differently stretched conformation and so allow detection of their elongation by atomic force microscopy. The laminar flow in this geometrically simple device has been characterized by adopting classical fluid dynamical models, in order to ensure well-known, stable shear rates which could be correlated quantitatively with an observed stretching of sensor molecules.
First-principles study of conducting behavior of warm dense neon
Authors: Tang J. , Chen Q. F. , Fu Z. J. , Li Z. G. , Quan W. L. , Gu Y. J. , Zheng J.
Published: August 2017

The energy gap of solid neon increases with density, which is an opposite density dependency compared to other noble gases. In order to investigate whether this abnormal phenomenon survives in the warm dense region, where the conducting behavior is closely related to the energy gap, we calculated the electrical conductivity of fluid neon for temperatures of 103–105 K and densities of 1.50–10.0 g/cm3 with a first-principles method. Temperature and density dependencies of conductivity in this region were analyzed. The results indicate that the conducting behavior is sensitive to the temperature; there is a significant increase in the direct current (dc) conductivity from 10 000 to 20 000 K. Contrary to other noble gases, we found an abnormal density dependency of dc conductivity, which decreases with increasing density at a given temperature. This phenomenon is due to the elevating localization of electrons and the broadening of the energy gap based on the analyses of charge density distribution and electronic structure under these extreme conditions. Finally, an insulating-conducting fluid phase diagram was constructed using our simulation results, which confirmed the conclusion of the latest experiment results.
Investigation of formation mechanism of Li-P dual-acceptor doped p-type ZnO
Authors: Sharma Pankaj , Bhardwaj Ritesh , Singh Rohit , Kumar Shailendra , Mukherjee Shaibal
Published: August 2017

In this work, the dual-acceptor doping method has been used to produce low resistive and stable p-type ZnO thin films. The ZnO:(Li, P) films were deposited on n-type Si substrates by dual ion beam sputtering. The p-type conduction was achieved by thermal annealing at 800 °C for 20 min in N2 ambient. The lowest resistivity of 0.016 Ω cm with a hole concentration and a Hall mobility of 2.31 × 1020 cm−3 and 1.6 cm2/V s, respectively, were obtained at an optimal deposition temperature of 300 °C. X-ray photoelectron spectroscopic analysis confirmed the formation of LiZn and PZn-2VZn acceptor complexes along with a trace of PO defects resulting in a high hole concentration.
Revisiting summer infertility in the pig: could heat stress-induced sperm DNA damage negatively affect early embryo development?
Authors: Peña, Jr Santiago T. , Gummow Bruce , Parker Anthony J. , Paris Damien B. B. P.
Published: August 2017

Temperature is a crucial factor in mammalian spermatogenesis. The scrotum, pampiniform plexus, and cremaster and dartos muscles in mammals are specific adaptations to ensure sperm production in a regulated environment 4−6°C below internal body temperature. However, the limited endogenous antioxidant systems inherent in mammalian spermatozoa compounded by the loss of cytosolic repair mechanisms during spermatogenesis, make the DNA in these cells particularly vulnerable to oxidative damage. Boar sperm is likely to be more susceptible to the effects of heat stress and thus oxidative damage due to the relatively high unsaturated fatty acids in the plasma membrane, low antioxidant capacity in boar seminal plasma, and the boar’s non-pendulous scrotum. Heat stress has a significant negative impact on reproductive performance in piggeries, which manifests as summer infertility and results in productivity losses that amount to millions of dollars. This problem is particularly prevalent in tropical and subtropical regions where ambient temperatures rise beyond the animal’s zone of thermal comfort. Based on preliminary studies in the pig and other species, this article discusses whether heat stress could induce sufficient DNA damage in boar sperm to significantly contribute to the high rates of embryo loss and pregnancy failure observed in the sow during summer infertility. Heat stress-induced damage to sperm DNA can lead to disrupted expression of key developmental genes essential for the differentiation of early cell lineages, such as the trophectoderm, and can distort the timely formation of the blastocyst; resulting in a failure of implantation and ultimately pregnancy loss. Confirming such a link would prompt greater emphasis on boar management and strategies to mitigate summer infertility during periods of heat stress.
ASKBILL as a web-based program to enhance sheep well-being and productivity
Authors: Kahn L. P. , Johnson I. R. , Rowe J. B. , Hogan L. , Boshoff J.
Published: August 2017

ASKBILL is a web-based program that uses farm measurements, climate data and information on genetics to predict pasture growth, animal performance and animal health and climate risks. The program uses several biophysical models, which are customised by user inputs, localised daily weather updates and a dynamical probabilistic 90-day climate forecast to enhance sheep well-being and productivity. This approach can minimise the requirement for manual, auto and remote measurements, thus reducing labour requirements and complexity. In this article, the animal growth model provides an example of a biophysical model used to provide predictions. This is an energy-based model and the model parameterisation is designed to be physiologically meaningful and able to be customised for the genetic merit of the animal using a growth coefficient that calibrates growth of body components and energy requirements. A key feature of the animal growth model is its forecast projections, which are based on an ensemble of simulations. The model can estimate supplementary feeding rates required to achieve target liveweights and body condition scores and stocking rates required to achieve target pasture levels. The model can be customised for a farm and its livestock and is updated daily in response to climate data. This dynamic feature enables it to provide early stage alerts to users when animal production targets are unlikely to be met.
Ecosystem restoration: recent advances in theory and practice
Authors: Jones T. A.
Published: August 2017

Restoration of damaged ecosystems is receiving increasing attention worldwide as awareness increases that humanity must sustain ecosystem structure, functioning, and diversity for its own wellbeing. Restoration will become increasingly important because our planet will sustain an increasingly heavy human footprint as human populations continue to increase. Restoration efforts can improve desirable ecological functioning, even when restoration to a historic standard is not feasible with current practice. Debate as to whether restoration is feasible is coupled to long-standing disputes regarding the definition of restoration, whether more-damaged lands are worthy of restoration efforts given limited financial resources, and ongoing conflicts as to whether the novel ecosystem concept is a help or a hindrance to restoration efforts. A willingness to consider restoration options that have promise, yet would have previously been regarded as ‘taboo’ based on the precautionary principle, is increasing. Functional restoration is becoming more prominent in the scientific literature, as evidenced by an increased emphasis on functional traits, as opposed to a simple inventory of vascular plant species. Biodiversity continues to be important, but an increasingly expansive array of provenance options that are less stringent than the traditional ‘local is best’ is now being considered. Increased appreciation for soil health, plant–soil feedbacks, biological crusts, and water quality is evident. In the United States, restoration projects are becoming increasingly motivated by or tied to remediation of major environmental problems or recovery of fauna that are either charismatic, for example, the monarch butterfly, or deliver key ecosystem services, for example, hymenopteran pollinators.
Glucocorticoids promote Von Hippel Lindau degradation and Hif-1α stabilization
Authors: Vettori Andrea , Greenald David , Wilson Garrick K. , Peron Margherita , Facchinello Nicola , Markham Eleanor , Sinnakaruppan Mathavan , Matthews Laura C. , McKeating Jane A. , Argenton Francesco , van Eeden Fredericus J. M.
Published: August 2017

Significance

An in vivo chemical screen in zebrafish identified glucocorticoids (GCs) as activators of hypoxia-inducible factor transcriptional responses in the liver. This cross-talk is conserved in human liver and requires glucocorticoid receptor signaling but not DNA binding. In human liver cells, GCs down-regulate Von Hippel Lindau expression at a posttranscriptional level most likely through c-src–mediated proteasomal degradation. Since the liver is an important regulator of blood glucose and hypoxia-inducible factors regulate gluconeogenesis/glycogen synthesis, cross-talk between these transcriptional regulators may be essential to control glucose metabolism in the liver. This identified, conserved, noncanonical pathway may have wider physiological significance in health and disease.
Teachers’ conceptualization and enactment of twenty‐first century competences: exploring dimensions for new curricula
Authors: van de Oudeweetering Karmijn , Voogt Joke
Published: August 2017

Despite the advocated importance of twenty‐first century competences in education, it appears that they are not systematically integrated in national curricula, school curricula and classroom activities. Potential explanations can be found in the current ambiguity of definitions for twenty‐first century competences and the absence of educational actors in curriculum development. Responding to both shortcomings, this study aims to explore how teachers’ conceptualization and enactment of twenty‐first century competences constitute dimensions that can inform curricular guidelines. An exploratory factor analysis of teachers’ self‐reported classroom activities that foster students’ twenty‐first century competences was conducted. The data comprised responses of 2,804 primary‐ and secondary‐school teachers to a web‐survey about the perceived occurrence of specific classroom activities targeting twenty‐first century competences. Results suggested six coherent dimensions of classroom activities that foster twenty‐first century competences: digital literacy, innovative thinking, critical thinking and communication, (digital) citizenship, self‐regulated learning, and (computer‐supported) collaborative learning. Nevertheless, there were substantial interrelationships among the six dimensions. This demonstrated that teachers did not perceive twenty‐first century competences to be fostered by disconnected classroom activities, but that they already have a more integrative conception of the curricular innovation. The implications of these findings for curricula, teaching practice and research are discussed.
Shoe drop reduction influences the lower limb biomechanics of children tennis players during an open stance forehand: A longitudinal study
Authors: Herbaut Alexis , Simoneau‐Buessinger Emilie , Barbier Franck , Gillet Christophe , Roux Maxime , Guéguen Nils , Chavet Pascale
Published: August 2017

Compared to traditional tennis shoes, using 0‐drop shoes was shown to induce an immediate switch from rear‐ to forefoot strike pattern to perform an open stance tennis forehand for 30% of children tennis players. The purpose of the study was to examine the long‐term effects of a gradual reduction in the shoe drop on the biomechanics of children tennis players performing open stance forehands. Thirty children tennis players participated in 2 laboratory biomechanical test sessions (intermediate: +4 months and final: +8 months) after an inclusion visit where they were randomly assigned to control (CON) or experimental (EXP) group. CON received 12‐mm‐drop shoes twice, whereas EXP received 8 mm then 4‐mm‐drop shoes. Strike index indicated that all CON were rearfoot strikers in intermediate and final test sessions. All EXP were rearfoot strikers in intermediate test session, but half the group switched towards a forefoot strike pattern in final test session. This switch resulted in a decreased loading rate of the ground reaction force (−73%, p = .005) but increased peak ankle plantarflexors moment (+47%, p = .050) and peak ankle power absorption (+107%, p = .005) for these participants compared with CON. Biomechanical changes associated with the long‐term use of partial minimalist shoes suggest a reduction in heel compressive forces but an increase in Achilles tendon tensile forces.
Metal assisted photochemical etching of 4H silicon
carbide
Authors: Leitgeb Markus , Zellner Christopher , Schneider Michael , Schwab Stefan , Hutter Herbert , Schmid Ulrich
Published: August 2017

Metal assisted photochemical etching (MAPCE) of 4H–silicon carbide (SiC) in
Na2S2O8/HF and
H2O2/HF aqueous solutions is investigated with platinum as
metallic cathode. The formation process of the resulting porous layer is studied
with respect to etching time, concentration and type of oxidizing agent. From
the experiments it is concluded that the porous layer formation is due to
electron hole pairs generated in the semiconductor, which stem from UV light
irradiation. The generated holes are consumed during the oxidation of
4H–SiC and the formed oxide is dissolved by HF. To maintain charge
balance, the oxidizing agent has to take up electrons at the Pt/etching solution
interface.

Total dissolution of the porous layers is achieved when the oxidizing agent
concentration decreases during MAPCE. In combination with standard
photolithography, the definition of porous regions is possible. Furthermore
chemical micromachining of 4 H–SiC at room temperature is possible.
On extremizers for Strichartz estimates for higher order Schrödinger equations
Authors: Oliveira e Silva Diogo , Quilodrán René
Published: August 2017

For an appropriate class of convex functions

ϕ
\phi

, we study the Fourier extension operator on the surface {(𝑦,|𝑦|²+𝜙(𝑦)):𝑦∈ℝ

²}

equipped with projection measure. For the corresponding extension inequality, we compute optimal constants and prove that extremizers do not exist. The main tool is a new comparison principle for convolutions of certain singular measures that holds in all dimensions. Using tools of concentration-compactness flavor, we further investigate the behavior of general extremizing sequences. Our work is directly related to the study of extremizers and optimal constants for Strichartz estimates of certain higher order Schrödinger equations. In particular, we resolve a dichotomy from the recent literature concerning the existence of extremizers for a family of fourth order Schrödinger equations and compute the corresponding operator norms exactly where only lower bounds were previously known.
Incircular nets and confocal conics
Authors: Akopyan Arseniy , Bobenko Alexander
Published: August 2017

We consider congruences of straight lines in a plane with the combinatorics of the square grid, with all elementary quadrilaterals possessing an incircle. It is shown that all the vertices of such nets (we call them incircular or IC-nets) lie on confocal conics.

Our main new results are on checkerboard IC-nets in the plane. These are congruences of straight lines in the plane with the combinatorics of the square grid, combinatorially colored as a checkerboard, such that all black coordinate quadrilaterals possess inscribed circles. We show how this larger class of IC-nets appears quite naturally in Laguerre geometry of oriented planes and spheres and leads to new remarkable incidence theorems. Most of our results are valid in hyperbolic and spherical geometries as well. We present also generalizations in spaces of higher dimension, called checkerboard IS-nets. The construction of these nets is based on a new

9
9

inspheres incidence theorem.
Wall divisors and algebraically coisotropic subvarieties of irreducible holomorphic symplectic manifolds
Authors: Knutsen Andreas , Lelli-Chiesa Margherita , Mongardi Giovanni
Published: August 2017

Rational curves on Hilbert schemes of points on

K
3

K3

surfaces and generalised Kummer manifolds are constructed by using Brill–Noether theory on nodal curves on the underlying surface. It turns out that all wall divisors can be obtained, up to isometry, as dual divisors to such rational curves. The locus covered by the rational curves is then described, thus exhibiting algebraically coisotropic subvarieties. This provides strong evidence for a conjecture by Voisin concerning the Chow ring of irreducible holomorphic symplectic manifolds. Some general results concerning the birational geometry of irreducible holomorphic symplectic manifolds are also proved, such as a non-projective contractibility criterion for wall divisors.
Control of pseudodifferential operators by maximal functions via weighted inequalities
Authors: Beltran David
Published: August 2017

We establish general weighted

L
2

L^2

inequalities for pseudodifferential operators associated to the Hörmander symbol classes

S

ρ
,
δ

m

S^m_{\rho ,\delta }

. Such inequalities allow one to control these operators by fractional “non-tangential” maximal functions and subsume the optimal range of Lebesgue space bounds for pseudodifferential operators. As a corollary, several known Muckenhoupt-type bounds are recovered, and new bounds for weights lying in the intersection of the Muckenhoupt and reverse Hölder classes are obtained. The proof relies on a subdyadic decomposition of the frequency space, together with applications of the Cotlar–Stein almost orthogonality principle and a quantitative version of the symbolic calculus.
Entropy, topological transitivity, and dimensional properties of unique 𝑞-expansions
Authors: Alcaraz Barrera Rafael , Baker Simon , Kong Derong
Published: August 2017

LetMMbe a positive integer andq∈(1,M+1].q \in (1,M+1].We consider expansions of real numbers in baseqqover the alphabet{0,…,M}\{0,\ldots , M\}. In particular, we study the setUq\mathcal {U}_{q}of real numbers with a uniqueqq-expansion, and the setUq\mathbf {U}_qof corresponding sequences.

It was shown by Komornik, Kong, and Li that the functionHH, which associates to eachq∈(1,M+1]q\in (1, M+1]the topological entropy ofUq\mathcal {U}_q, is a Devil’s staircase. In this paper we explicitly determine the plateaus ofHH, and characterize the bifurcation setE\mathscr {E}ofqq’s where the functionHHis not locally constant. Moreover, we show thatE\mathscr {E}is a Cantor set of full Hausdorff dimension. We also investigate the topological transitivity of a naturally occurring subshift(Vq,σ),(\mathbf {V}_q, \sigma ),which has a close connection with open dynamical systems. Finally, we prove that the Hausdorff dimension and box dimension ofUq\mathcal {U}_qcoincide for allq∈(1,M+1]q\in (1,M+1].
Community development and Historic Preservation: Exploring intersections in Seattle’s Chinatown-International District
Authors: Ryberg-Webster Stephanie
Published: August 2017

Urban neighbourhoods are home to complex social interactions, cultural traditions and historic built environments that have accrued over time. Many community development corporations (CDCs) in the United States work in older, inner-city neighbourhoods, setting the stage for a possible alliance with historic preservation. This paper explores the intersection of community development and historic preservation, asking: In high-growth contexts, how do community developers working in neighbourhoods with strong cultural and ethnic identity use historic preservation? What are their motivations? And, how do they define, use, and/or adapt preservation to address the needs of their target communities? The article chronicles the Seattle Chinatown-International District Preservation Development Authority’s (SCIDpda) efforts to reverse neighbourhood decline while preserving the International District’s significant history, fostering its continued future as a Pan-Asian community, overcoming persistent barriers to development, and mitigating high growth pressures. The findings show that for community developers, preservation can serve as an oppositional strategy to demolition and incompatible new development, helping to attract outside financial resources, and providing a means to assert local symbolic ownership over neighbourhood space.
1. Aims, themes, and structure
Authors: Partington Martin
Published: August 2017

This chapter presents the aims, themes, and structure of this book. The book provides an introductory account of the English legal system, how it has developed in recent years, and how it may develop in future. Part II raises fundamental issues about the social functions of law and the legitimacy of law; and considers the institutional framework within which law is made. Part III looks at the different context in which law is developed and practised. Part IV looks at the delivery and funding of legal services. Part V returns to the theme of transformation and the challenges to be faced.
2. Law and society: the purposes and functions of law
Authors: Partington Martin
Published: August 2017

This chapter discusses social functions of law at the macro and micro levels. The macro functions of law cover law and public order, political order, social order, economic order, international order, and moral order. They also include the resolution of social problems, the regulation of human relationships, and the educative or ideological function of law. The micro functions of law include defining the limits of acceptable behaviour, the consequences of certain forms of behaviour, and processes for the transaction of business and other activities, as well as creating regulatory frameworks, giving authority to agents of the state to take actions against citizens, preventing the abuse of power by officials, giving power/authority to officials to assist the public, and prescribing procedures for the use of law.
4. Shaping the legal system: the role of government
Authors: Partington Martin
Published: August 2017

This chapter considers the principal government departments that have been shaping and will continue to shape the English legal system. The leading department is the Ministry of Justice which is responsible for running and developing the courts and tribunals system. The chapter provides an overview of its functions. The Home Office is responsible for many aspects of criminal justice policy. Mention is also made of the Department for Business Energy and Industrial Strategy, and other central government departments whose work impacts on the legal system.
6. The administrative justice system
Authors: Partington Martin
Published: August 2017

This chapter focuses on administrative justice. It reflects on the nature of administrative law and the role it plays in modern society. It then discusses the bodies and processes that make up the institutional framework of administrative justice. It also considers the responsibilities of Parliament in holding government to account. In addition, it asks who has general oversight of the system.
7. The family justice system
Authors: Partington Martin
Published: August 2017

This chapter discusses the family justice system. It considers the role law plays in regulating the family. It covers the institutional framework of family justice; creation of the family court; the remedies available in that court; adoption; other matrimonial matters. It considers policy relating to child support, and notes changes to ways of dealing with domestic violence. It considers the legal practitioners involved in family law issues and changes to legal aid for funding for family law cases.
9. Delivering legal services: practitioners, adjudicators, and legal scholars
Authors: Partington Martin
Published: August 2017

This chapter discusses the role both of those professionally qualified to practise law and of other groups who provide legal services but who are not formally qualified as lawyers. It examines how regulation of legal services providers has changed. It notes new forms of legal practice. It considers the adjudicators and other dispute resolvers who play a significant role in the working of the legal system. It reflects on the contribution made by law teachers, in universities and in private colleges, to the formation of the legal profession and to the practice of the law.
Small Aneurysms Account for the Majority and Increasing Percentage of Aneurysmal Subarachnoid Hemorrhage: A 25-Year, Single Institution Study
Authors: Bender Matthew T , Wendt Haley , Monarch Thomas , Beaty Narlin , Lin Li-Mei , Huang Judy , Coon Alexander , Tamargo Rafael J , Colby Geoffrey P
Published: August 2017

BACKGROUND

Prospective studies of unruptured aneurysms have shown very low rates of rupture for small aneurysms (<10 mm) and suggested that the risk of treatment outweighs benefit. However, common clinical practice shows that patients with aneurysmal subarachnoid hemorrhage (aSAH) frequently have small aneurysms.

OBJECTIVE

To investigate trends in size and location of ruptured aneurysms over a 25-yr period.

METHODS

A prospective, Institutional Review Board-approved database of all patients presenting to our institution with aSAH from 1991 to 2016 was analyzed. Cerebral angiography identified the source of hemorrhage. Patients with nonaneurysmal etiologies were excluded.

RESULTS

Complete data were available for 1306/1562 patients (84%) with aSAH from 1991 to 2016. The average age was 53 yr and 72% of patients were female. The average size of ruptured aneurysms over 25 yr was 8.0 mm. The average size of ruptured aneurysms decreased steadily with each 5-yr interval from 10.1 mm (1991-1996) to 6.6 mm (2012-2016; P < .001). Overall, very small aneurysms (<5 mm) were responsible for aSAH in 41% of patients. The percentage of very small ruptured aneurysms rose from 29% during the initial 5-yr period (1991-1996) to 50% in the most recent period. Likewise, the percentage of ruptured aneurysms that were 5 to 9 mm rose from 26% to 34% (P < .001). In the past 5 yr, aneurysms <10 mm accounted for 84% of aSAH. Vessel of origin (P = .097) and aneurysm location (P = .322) did not vary with time.

CONCLUSION

Ruptured small and very small aneurysms represent a majority and increasing share of aSAH. Identification and prophylactic treatment of these aneurysms remains an important clinical role for cerebrovascular neurosurgery.
Gaming for Health: Systematic Review and Meta-analysis of the Physical and Cognitive Effects of Active Computer Gaming in Older Adults
Authors: Howes Sarah C. , Charles Darryl K. , Marley Joanne , Pedlow Katy , McDonough Suzanne M.
Published: August 2017

Background

Active computer gaming (ACG) is a method of facilitating physical activity in older people to improve health outcomes.

Purpose

The purpose of this study was to update and extend a systematic review of the evidence for ACG to determine its effects on physical and cognitive health in older adults.

Data Sources

MEDLINE, EMBASE, CENTRAL in the Cochrane Library, and PsycINFO databases were searched from the date of the previous review (2011) to May 2016.

Study Selection

Eligible articles were randomized controlled trials (RCTs) investigating the effect of ACG in adults aged 65 and older.

Data Extraction

Thirty-five studies were eligible for inclusion. Two review authors independently conducted data extraction, risk-of-bias assessment, and coding of behavior change techniques. Outcomes of interest were analyzed as continuous data and pooled as standardized mean differences (SMD) and 95% confidence intervals (CI). The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to determine the quality of the evidence.

Data Synthesis

Behavior change techniques (N = 106) were coded in the included studies (mean = 3.02). Data were pooled for 5 main outcomes of interest. Significant moderate effects in favor of ACG were observed for balance (SMD = 0.52, 95% CI = 0.24 to 0.79; 17 studies; 743 participants), for functional exercise capacity when intervention delivery was >120 minutes per week (SMD = 0.53, 95% CI = 0.15 to 0.90; 5 studies; 116 participants), and for cognitive function (SMD = –0.48, 95% CI = –0.80 to 0.17; 8 studies; 459 participants). There was no significant effect observed for functional mobility or fear of falling.

Limitations

The quality of the evidence for all comparisons was graded low or very low.

Conclusions

At present there is very little confidence that ACG improves physical and cognitive outcomes in older adults.
Naloxegol for managing opioid-induced constipation
Authors: Shelton Krystal N. , Clements Jennifer N.
Published: August 2017

Naloxegol is a peripherally acting mu-opioid receptor antagonist for opioid-induced constipation in adults with chronic noncancer pain. This drug's once-daily oral formulation can be used as monotherapy and helps to decrease the constipating effects of opioid therapy; however, it has been associated with abdominal pain.
Stability of Auditory Steady State Responses Over Time
Authors: Van Eeckhoutte Maaike , Luke Robert , Wouters Jan , Francart Tom
Published: August 2017

Objectives:

Auditory steady state responses (ASSRs) are used in clinical practice for objective hearing assessments. The response is called steady state because it is assumed to be stable over time, and because it is evoked by a stimulus with a certain periodicity, which will lead to discrete frequency components that are stable in amplitude and phase over time. However, the stimuli commonly used to evoke ASSRs are also known to be able to induce loudness adaptation behaviorally. Researchers and clinicians using ASSRs assume that the response remains stable over time. This study investigates (1) the stability of ASSR amplitudes over time, within one recording, and (2) whether loudness adaptation can be reflected in ASSRs.

Design:

ASSRs were measured from 14 normal-hearing participants. The ASSRs were evoked by the stimuli that caused the most loudness adaptation in a previous behavioral study, that is, mixed-modulated sinusoids with carrier frequencies of either 500 or 2000 Hz, a modulation frequency of 40 Hz, and a low sensation level of 30 dB SL. For each carrier frequency and participant, 40 repetitions of 92 sec recordings were made. Two types of analyses were used to investigate the ASSR amplitudes over time: with the more traditionally used Fast Fourier Transform and with a novel Kalman filtering approach. Robust correlations between the ASSR amplitudes and behavioral loudness adaptation ratings were also calculated.

Results:

Overall, ASSR amplitudes were stable. Over all individual recordings, the median change of the amplitudes over time was −0.0001 μV/s. Based on group analysis, a significant but very weak decrease in amplitude over time was found, with the decrease in amplitude over time around −0.0002 μV/s. Correlation coefficients between ASSR amplitudes and behavioral loudness adaptation ratings were significant but low to moderate, withr= 0.27 andr= 0.39 for the 500 and 2000 Hz carrier frequency, respectively.

Conclusions:

The decrease in amplitude of ASSRs over time (92 sec) is small. Consequently, it is safe to use ASSRs in clinical practice, and additional correction factors for objective hearing assessments are not needed. Because only small decreases in amplitudes were found, loudness adaptation is probably not reflected by the ASSRs.