bluuebunny/crossref_metadata_2025 huggingface dataset:
Changing Management of the Patent Ductus Arteriosus: Effect on Neonatal Outcomes and Resource Utilization
Authors: Goel Veena , Palma Jonathan , Luh Thomas , Wang Nichole , Gaskari Shabnam , Punn Rajesh , Silverman Norman , Benitz William , Chock Valerie
Published: April 2017

Objective This historical cohort study investigated how a shift toward a more conservative approach of awaiting spontaneous closure of the patent ductus arteriosus (PDA) in preterm infants has affected neonatal outcomes and resource utilization.

Methods We retrospectively studied very low birth weight infants diagnosed with a PDA by echocardiogram (ECHO) in 2006–2008 (era 1), when medical or surgical PDA management was emphasized, to those born in 2010–2012 (era 2) when conservative PDA management was encouraged. Multiple regression analyses adjusted for gestational age were performed to assess differences in clinical outcomes and resource utilization between eras.

Results More infants in era 2 (35/89, 39%) compared with era 1 (22/120, 18%) had conservative PDA management (p < 0.01). Despite no difference in surgical ligation rate, infants in era 2 had ligation later (median 24 vs. 8 days, p < 0.0001). There was no difference in clinical outcomes between eras, while number of ECHOs per patient was the only resource measure that increased in era 2 (median 3 vs. 2 ECHOs, p = 0.003).

Conclusion In an era of more conservative PDA management, no increase in adverse clinical outcomes or significant change in resource utilization was found. Conservative PDA management may be a safe alternative for preterm infants.
Endoscopic resection of large duodenal and papillary lateral spreading lesions is clinically and economically advantageous compared with surgery
Authors: Klein Amir , Ahlenstiel Golo , Tate David , Burgess Nicholas , Richardson Arthur , Pang Tony , Byth Karen , Bourke Michael
Published: April 2017

Background and study aims Adenomas of the duodenum and ampulla are uncommon. For lesions ≤ 20 mm in size and confined to the papillary mound, endoscopic resection is well supported by systematic study. However, for large laterally spreading lesions of the duodenum or papilla (LSL-D/P), surgery is often performed despite substantial associated morbidity and mortality. We aimed to compare actual endoscopic outcomes of such lesions and costs with those predicted for surgery using validated prediction tools.

Patients and methods Patients who underwent endoscopic resection of LSL-D/P were analyzed. Two surgeons assigned the hypothetical surgical management. The National Surgical Quality Improvement Program (NSQIP), and the Portsmouth Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM) were used to predict morbidity, mortality, and length of hospital stay. Actual endoscopic and hypothetical surgical outcomes and costs were compared.

Results A total of 102 lesions were evaluated (mean age of patients 69 years, 52 % male, mean lesion size 40 mm). Complete endoscopic resection was achieved in 93.1 % at the index procedure. Endoscopic adverse events occurred in 18.6 %. Recurrence at first surveillance endoscopy was seen in 17.7 %. For patients with ≥ 2 surveillance endoscopies (n = 55), 90 % were clear of disease and considered cured (median follow-up 27 months). Compared with hypothetical surgical resection, endoscopic resection had less morbidity (18 % vs. 31 %; P = 0.001) and shorter hospital stay (median 1 vs. 4.75 days; P < 0.001), and was less costly than surgery (mean $ 11 093 vs. $ 19 358; P < 0.001).

Conclusion In experienced centers, even extensive LSL-D/P can be managed endoscopically with favorable morbidity and mortality profiles, and reduced costs, compared with surgery.
150 mW deep-ultraviolet light-emitting diodes with large-area AlN nanophotonic light-extraction structure emitting at 265 nm
Authors: Inoue Shin-ichiro , Tamari Naoki , Taniguchi Manabu
Published: April 2017

High-power 265 nm deep-ultraviolet (DUV) AlGaN-based light-emitting diodes (LEDs) with large-area AlN nanophotonic light-extraction structures that were fabricated by a nanoimprint lithography process are presented. Each DUV-LED has a large active area (mesa size of ∼0.35 mm2) and a uniform current spreading design that allows high injection current operation. We have shown that these DUV-LEDs with their large-area nanoimprinted AlN nanophotonic structures exhibit wider near-field emitting areas, stronger far-field extracted light intensities, and an approximately 20-fold increase in output power when compared with a conventional flat-surface DUV-LED. A large-area nanoimprinted single-chip DUV-LED operating in the UV-C wavelength regime has demonstrated a record continuous-wave output power in excess of 150 mW for an injection current of 850 mA at a peak emission wavelength of 265 nm.
Monte-Carlo modelling to determine optimum filter choices for sub-microsecond optical pyrometry
Authors: Ota Thomas A. , Chapman David J. , Eakins Daniel E.
Published: April 2017

When designing a spectral-band pyrometer for use at high time resolutions (sub-μs), there is ambiguity regarding the optimum characteristics for a spectral filter(s). In particular, while prior work has discussed uncertainties in spectral-band pyrometry, there has been little discussion of the effects of noise which is an important consideration in time-resolved, high speed experiments. Using a Monte-Carlo process to simulate the effects of noise, a model of collection from a black body has been developed to give insights into the optimum choices for centre wavelength and passband width. The model was validated and then used to explore the effects of centre wavelength and passband width on measurement uncertainty. This reveals a transition centre wavelength below which uncertainties in calculated temperature are high. To further investigate system performance, simultaneous variation of the centre wavelength and bandpass width of a filter is investigated. Using data reduction, the effects of temperature and noise levels are illustrated and an empirical approximation is determined. The results presented show that filter choice can significantly affect instrument performance and, while best practice requires detailed modelling to achieve optimal performance, the expression presented can be used to aid filter selection.
Exact analytical solution for large-amplitude oscillatory shear flow from Oldroyd 8-constant framework: Shear stress
Authors: Saengow C. , Giacomin A. J. , Kolitawong C.
Published: April 2017

The Oldroyd 8-constant model is a continuum framework containing, as special cases, many important constitutive equations for elastic liquids. When polymeric liquids undergo large-amplitude oscillatory shear flow, the shear stress responds as a Fourier series, the higher harmonics of which are caused by the fluid nonlinearity. We choose this continuum framework for its rich diversity of special cases (we tabulate 14 of these). Deepening our understanding of this Oldroyd 8-constant framework thus at once deepens our understanding of every one of these special cases. Previously [C. Saengow et al., Macromol. Theory Simul. 24, 352 (2015)], we arrived at an exact analytical solution for the corotational Maxwell model. Here, we derive the exact analytical expression for the Oldroyd 8-constant framework for the shear stress response in large-amplitude oscillatory shear flow. Our exact solution reduces to our previous solution for the special case of the corotational Maxwell model, as it should. Our worked example uses the special case of the corotational Jeffreys model to explore the role of η∞ on the higher harmonics.
Covalent bonding in heavy metal oxides
Authors: Bagus Paul S. , Nelin Connie J. , Hrovat Dave A. , Ilton Eugene S.
Published: April 2017

Novel theoretical methods were used to quantify the magnitude and the energetic contributions of 4f/5f-O2p and 5d/6d-O2p interactions to covalent bonding in lanthanide and actinide oxides. Although many analyses have neglected the involvement of the frontier d orbitals, the present study shows that f and d covalencies are of comparable importance. Two trends are identified. As is expected, the covalent mixing is larger when the nominal oxidation state is higher. More subtly, the importance of the nf covalent mixing decreases sharply relative to (n + 1)d as the nf occupation increases. Atomic properties of the metal cations that drive these trends are identified.
A general theoretical description of the influence of isotropic chemical shift in dipolar recoupling experiments for solid-state NMR
Authors: Shankar Ravi , Ernst Matthias , Madhu P. K. , Vosegaard Thomas , Nielsen Niels Chr. , Nielsen Anders B.
Published: April 2017

We present a general theoretical description that allows us to describe the influence of isotropic chemical shift in homonuclear and heteronuclear dipolar recoupling experiments in magic-angle-spinning solid-state NMR. Through a transformation of the Hamiltonian into an interaction frame with the combined radio-frequency irradiation and the isotropic chemical shift, we determine an effective Hamiltonian to first order with respect to the relevant internal nuclear spin interactions. This unravels the essential resonance conditions for efficient dipolar recoupling. Furthermore, we propose how to handle situations where the resonance conditions are not exactly fulfilled. To verify the general theoretical description, we compare numerical simulations using a time-sliced time-dependent Hamiltonian with simulations using the calculated effective Hamiltonian for propagation. The comparisons are exemplified for the homonuclear dipolar recoupling experiments C721 and POST-C721.
Surface waves on currents with arbitrary vertical shear
Authors: Smeltzer Benjamin K. , Ellingsen Simen Å.
Published: April 2017

We study dispersion properties of linear surface gravity waves propagating in an arbitrary direction atop a current profile of depth-varying magnitude using a piecewise linear approximation and develop a robust numerical framework for practical calculation. The method has been much used in the past for the case of waves propagating along the same axis as the background current, and we herein extend and apply it to problems with an arbitrary angle between the wave propagation and current directions. Being valid for all wavelengths without loss of accuracy, the scheme is particularly well suited to solve problems involving a broad range of wave vectors, such as ship waves and Cauchy-Poisson initial value problems. We examine the group and phase velocities over different wavelength regimes and current profiles, highlighting characteristics due to the depth-variable vorticity. We show an example application to ship waves on an arbitrary current profile and demonstrate qualitative differences in the wake patterns between concave down and concave up profiles when compared to a constant shear profile with equal depth-averaged vorticity. We also discuss the nature of additional solutions to the dispersion relation when using the piecewise-linear model. These are vorticity waves, drifting vortical structures which are artifacts of the piecewise model. They are absent for a smooth profile and are spurious in the present context.
Tunneling effects in the unimolecular decay of (CH3)2COO Criegee intermediates to OH radical products
Authors: Fang Yi , Barber Victoria P. , Klippenstein Stephen J. , McCoy Anne B. , Lester Marsha I.
Published: April 2017

Unimolecular decay of the dimethyl substituted Criegee intermediate (CH3)2COO is observed at energies significantly below the transition state barrier associated with hydrogen atom transfer [Y. Fang et al., J. Chem. Phys. 144, 061102 (2016)] with time-resolved detection of the resultant OH radical products. (CH3)2COO is prepared at specific energies in the 3900-4600 cm−1 region through IR excitation of combination bands involving CH stretch and another lower frequency mode, and the OH products are detected by UV laser-induced fluorescence. OH appearance times on the order of microseconds are observed in this deep tunneling regime, which are about 100 times slower than that in the vicinity of the barrier. The experimental rates are in good accord with Rice–Ramsperger–Kassel–Marcus (RRKM) calculations of the microcanonical dissociation rates for (CH3)2COO that include tunneling. Master equation modeling based on these microcanonical rates is used to predict the thermal decay rate of (CH3)2COO to OH products under atmospheric conditions of 276 s−1 at 298 K (high pressure limit). Thermal unimolecular decay of (CH3)2COO to OH products is shown to have significant contributions from tunneling at energies much below the barrier to H-atom transfer.
Transformation of amorphous to crystallized carbon
Authors: Lee Ju Ho , Song Young Seok , Lim Eunju
Published: April 2017

Graphene has attracted much attention in materials science and electronics because of its high conductivity, strong mechanical strength, excellent flexible properties, etc. The favored fabrication method of graphene is using methane by chemical vapor deposition. Through this method high quality and large-scale monolayer graphene has been prepared. However, this graphene is not suitable for use in preparation of logical transistor devices, owing to the insufficient band gap. On the other hand, graphene nanoribbon has a finite band gap and a N-doped graphene monolayer shows a low on/off current ratio. Therefore, it is necessary to develop fabrication techniques for making graphene that is appropriate for logic devices. This paper introduces an easy fabrication method that does not need a methane source, where a solid phase source transformation to crystallize graphene is carried out on polycrystalline Copper foil, and a N-doped graphene layer is produced. Bilayer graphene is found to be achieved at most hydrogen flow rates.
Evaluating the control of a cylinder wake by the method of sensitivity analysis
Authors: Patino G. A. , Gioria R. S. , Meneghini J. R.
Published: April 2017

Numerical simulations and sensitivity analysis are carried out regarding control vortex shedding from a circular cylinder using small rotating and non-rotating control cylinders. Prediction of the changes in unsteady wake, instability growth rate, and frequency produced by the control devices is presented in the framework of sensitivity analysis to steady field force. In the case of the rotating cylinders, this prediction relies on the observation that the small control cylinders introduce a steady force whose direction is not aligned to the base flow direction. This external force direction depends on the control cylinders rotation rates having an additional parameter to attain flow control. The evaluation of the control cylinders rotation rate within the sensitivity analysis framework is a novel contribution in this work. The results of the sensitivity analysis to a steady force are then compared to direct numerical simulation computations of the flow fields serving as supporting data for discussion.
Self-driven visible-blind photodetector based on ferroelectric perovskite oxides
Authors: Li Jian-kun , Ge Chen , Jin Kui-juan , Du Jian-yu , Yang Jing-ting , Lu Hui-bin , Yang Guo-zhen
Published: April 2017

Ultraviolet photodetectors have attracted considerable interest for a variety of applications in health, industry, and science areas. Self-driven visible-blind photodetectors represent an appealing type of sensor, due to the reduced size and high flexibility. In this work, we employed BaTiO3 (BTO) single crystals with a bandgap of 3.2 eV for the realization of a self-driven ultraviolet detector, by utilizing the ferroelectric properties of BTO. We found that the sign of the photocurrent can be reversed by flipping the ferroelectric polarization, which makes the photodetector suitable for electrical manipulation. The photoelectric performance of this photodetector was systematically investigated in terms of rectification character, stability of short-circuit photocurrent, spectral response, and transient photoelectric response. Particularly, the self-driven photodetectors based on BTO showed an ultrafast response time about 200 ps. It is expected that the present work can provide a route for the design of photodetectors based on ferroelectric oxides.
Flexural wave suppression by an elastic metamaterial beam with zero bending
stiffness
Authors: Zhang Yong Yan , Wu Jiu Hui , Hu Guang Zhong , Wang Yu Chun
Published: April 2017

In this paper, different from Bragg scattering or local resonance mechanisms, a novel mechanism of an ultra-low-frequency broadband for flexural waves propagating in a one-dimensional elastic metamaterial beam with zero bending stiffness is proposed, which consists of periodic hinge-linked blocks. The dispersion relationship of this kind of metamaterial beam is derived and analyzed, from which we find that these hinge-linked blocks can produce the zero bending stiffness. Thus, the flexural waves within the metamaterial beam can be suppressed, and an ultra-low-frequency wide band-gap is formed in which the first branch is generated by the zero bending spring and the second branch by the negative velocity of the metamaterial beam. Numerical results show that the elastic metamaterial beams with zero bending stiffness can indeed generate an ultra-low-frequency wide band gap even starting from almost zero frequency, such as from 0 Hz to 525 Hz in our structure. Therefore, the puzzle of realizing an ultra-low-frequency broadband of flexural waves may have been better solved, which could be applied in controlling ultra-low-frequency elastic waves in engineering.

At the request of the Editor and the Publisher this article is being retracted. It was inadvertently published in Journal of Applied Physics due to the significant overlap of data, experimental approach, and results with another publication with no acknowledgment.
Vanadium in silicon: Lattice positions and electronic properties
Authors: Mullins Jack , Markevich Vladimir P. , Halsall Matthew P. , Peaker Anthony R.
Published: April 2017

The electronic properties of vanadium in silicon have been studied using deep level transient spectroscopy (DLTS), high resolution Laplace DLTS, capacitance voltage measurements and secondary ion mass spectroscopy (SIMS). Vanadium was implanted into float zone (FZ) grown n-type and FZ and Czochralski (Cz) grown p-type Si and implantation damage was removed through annealing between 700 and 900 °C. DLTS measurements were carried out to determine the electronic characteristics of vanadium-related defects in silicon. It is argued that the dominant electrically active defect is related to interstitial vanadium (Vi) atoms. The distribution of implanted vanadium is seen to differ between Czochralski and FZ silicon, with redistribution of vanadium atoms occurring significantly faster in Cz-Si. We suggest that in FZ-Si the Vi atoms interact with implantation induced vacancies and move to the substitutional site where they are much less mobile. At the peak concentration of vanadium, determined by SIMS to be ∼1015 cm−3 in FZ-Si, the electrically active fraction is significantly lower (∼1013 cm–3). As we see no evidence of precipitation occurring in the region close to the implant peak, it is concluded that a large portion of V atoms should be located at the substitutional site. Despite the ab-initio modeling predictions of substitutional vanadium, Vs, introducing a shallow acceptor level in the silicon band gap, no electrical activity associated with the Vs fraction has been observed in this work in spite of its concentration being at a measurable level. As such, our results indicate that substitutional vanadium is electrically inactive in silicon.
High pulsed current density β-Ga2O3 MOSFETs verified by an analytical model corrected for interface charge
Authors: Moser Neil A. , McCandless Jonathan P. , Crespo Antonio , Leedy Kevin D. , Green Andrew J. , Heller Eric R. , Chabak Kelson D. , Peixoto Nathalia , Jessen Gregg H.
Published: April 2017

We report on Sn-doped β-Ga2O3 MOSFETs grown by molecular beam epitaxy with as-grown carrier concentrations from 0.7 × 1018 to 1.6 × 1018 cm−3 and a fixed channel thickness of 200 nm. A pulsed current density of >450 mA/mm was achieved on the sample with the lowest sheet resistance and a gate length of 2 μm. Our results are explained using a simple analytical model with a measured gate voltage correction factor based on interface charges that accurately predict the electrical performance for all doping variations.
Two-dimensional time-resolved ultra-high speed imaging of K-alpha emission from short-pulse-laser interactions to observe electron recirculation
Authors: Nagel S. R. , Chen H. , Park J. , Foord M. , Hazi A. U. , Hilsabeck T. J. , Kerr S. M. , Marley E. V. , Williams G. J.
Published: April 2017

Time resolved x-ray images with 7 ps resolution are recorded on relativistic short-pulse laser-plasma experiments using the dilation x-ray imager, a high-speed x-ray framing camera, sensitive to x-rays in the range of ≈1−17 keV. This capability enables a series of 2D x-ray images to be recorded at picosecond scales, which allows for the investigation of fast electron transport within the target with unprecedented temporal resolution. An increase in the Kα-emission spot size over time was found for targets thinner than the recirculation limit and is absent for thicker targets. Together with the observed polarization dependence of the spot size increase, this indicates that electron recirculation is relevant for the x-ray production in thin targets.
Angle-resolved and polarization-dependent investigation of cross-shaped frequency-selective surface terahertz filters
Authors: Ferraro A. , Zografopoulos D. C. , Caputo R. , Beccherelli R.
Published: April 2017

The spectral response of a terahertz (THz) filter is investigated in detail for different angles of incidence and polarization of the incoming THz wave. The filter is fabricated by patterning an aluminum frequency-selective surface of cross-shaped apertures on a thin foil of the low-loss cyclo-olefin polymer Zeonor. Two different types of resonances are observed, namely, a broadline resonance stemming from the transmittance of the slot apertures and a series of narrowline guided-mode resonances, with the latter being investigated by employing the grating theory. Numerical simulations of the filter transmittance based on the finite-element method agree with experimental measurements by means of THz time domain spectroscopy (THz-TDS). The results reveal extensive possibilities for tuning the guided-mode resonances by mechanically adjusting the incidence or polarization angle, while the fundamental broadline resonance is not significantly affected. Such filters are envisaged as functional elements in emerging THz systems for filtering or sensing applications.
Frequency latching in nonlinear micromechanical resonators
Authors: Wei Xueyong , Zhang Tianyi , Jiang Zhuangde , Ren Juan , Huan Ronghua
Published: April 2017

The resonance frequency of a nonlinear micromechanical resonator has a dependence on its modal amplitude known as the A–f effect. Here, we experimentally demonstrated that the A–f effect can be limited by the mode interaction in micromechanical resonators. The clamped-clamped beam resonator investigated in this work has a nonlinear in-plane (IP) vibration mode and a linear out-of-plane (OOP) vibration mode. In the case of single ended driving with various Vdc, the resonance frequency of the IP mode tuned through the A–f effect reaches that of the OOP mode and is limited by the OOP mode due to the modal interaction and electrostatic softening effect. In the case of double ended driving, however, the resonance frequency of the IP mode is latched to that of the OOP mode after A–f tuning and a frequency stabilized region is observed. A theoretical model is also put forward to explain this phenomenon through numerical simulations.
The study of separation of crystal Fe and morphology for FeB nanoparticle: Molecular dynamics simulation
Authors: Huu Kien Pham , Thi Thuy Trang Giap , Khac Hung Pham
Published: April 2017

The separation of Fe crystal from amorphous nanoparticle (NP) has been studied using molecular dynamics simulation. The simulation shows that the NP is crystallized through three stages. In the first stage NP undergoes the relaxation which results in forming nucleation regions where the atomic arrangement is similar to the distorted crystalline lattice. During the first stage the nuclei are unstable and dissolve for short times. In the second stage the stable crystal clusters have been created and new nuclei are formed mainly in the boundary region of crystal cluster. The stable crystal cluster grows in the direction to cover the core and then spreads out to the surface of NP. For the third stage the crystal cluster grows slightly with times. Further study concerns the different morphologies of NP. We found that the crystalline NP comprises a Fe crystalline grain with defects and separate clusters of Am-atom. Comparing to the amorphous NP, the structure organization of crystalline NP is more complicated and cannot be described by the simple shell/core model.
Temperature effect on redox voltage in LixCo[Fe(CN)6]y
Authors: Magnússon Rögnvaldur Líndal , Kobayashi Wataru , Takachi Masamitsu , Moritomo Yutaka
Published: April 2017

The electrochemical thermoelectric (TE) coefficient (SEC≡∂V∂T; V and T are the redox potential and temperature, respectively) is a significant material parameter, because it enable us to convert heat into electricity. Here, we systematically investigated the TE properties of cobalt hexacyanoferrate (Co-HCF), LixCo[Fe(CN)6]y, against the Li concentration (x). |SEC| is higher than the Seebeck coefficient (= 0.2 mV/K at room temperature) of Bi2Te3 and distributes from 0.2 to 0.8 mV/K. We further observed a sign reversal behavior of SEC: SEC is negative at y =0.71 while it is negative (positive) at x≤0.3 (x≥0.6) at y =0.90. Based on the ionic model, we qualitatively reproduced the sign reversal behavior by including the volume expansion effect. These arguments suggest that SEC in solid is mainly governed by the electrostatic energy.
Magnetic properties of polycrystalline cobalt nanoparticles
Authors: Bautin V. A. , Seferyan A. G. , Nesmeyanov M. S. , Usov N. A.
Published: April 2017

The energy diagram of stationary magnetization states existing in polycrystalline cobalt nanoparticles in the range of diameters 20 ≤ D ≤ 60 nm has been calculated by means of numerical simulation. It is shown that in polycrystalline cobalt nanoparticles in the range of diameters D ≥ 32 nm only vortex states with low average magnetization are present, whereas mostly quasi-uniform states are realized in nanoparticles with diameter D ≤ 24 nm. Thus, the effective single-domain diameter of polycrystalline cobalt nanoparticles is estimated to be Dc = 24 nm. It is approximately two times smaller than the actual single-domain diameter of monocrystalline cobalt nanoparticle, Dc0 = 45 nm. The hysteresis loops of a dilute assembly of polycrystalline cobalt nanoparticles in the range of diameters D ≤ Dc are characterized by a coercive force that is approximately 2.5 times less compared with that of the randomly oriented assembly of monocrystalline cobalt nanoparticles.
Thickness-dependent magnetic and electrical transport properties of epitaxial La0.7Sr0.3CoO3 films
Authors: Li Binzhi , Chopdekar Rajesh V. , Kane Alexander M. , Hoke Kyle , N’Diaye Alpha T. , Arenholz Elke , Takamura Yayoi
Published: April 2017

The thickness-dependent magnetic and electrical transport properties of nearly strain-free La0.7Sr0.3CoO3 (LSCO) films grown on (001)-oriented (LaAlO3)0.3 (Sr2AlTaO6)0.7 substrates were systematically studied. A crossover from ferromagnetic/metallic to non-magnetic/insulating behavior occurs at a critical thickness (∼8 nm) that is significantly smaller than LSCO films under larger strains in reported literature. X-ray absorption measurements revealed that the difference of functional properties at reduced film thicknesses was accompanied by changes in the valence state of Co ions at the film/substrate interface.
Erbium diffusion in titanium dioxide
Authors: Basse Louise , Hansen John Lundsgaard , Jensen Pia Bomholt , Julsgaard Brian
Published: April 2017

The diffusivity of erbium in the anatase phase of titanium dioxide (TiO2) has been studied for various temperatures ranging from 800 °C to 1, 000 °C. Samples of TiO2, with a 10 nm thick buried layer containing 0.5 at% erbium, were fabricated by radio-frequency magnetron sputtering and subsequently heat treated. The erbium concentration profiles were measured by secondary ion mass spectrometry, allowing for determination of the temperature-dependent diffusion coefficients. These were found to follow an Arrhenius law with an activation energy of (2.1±0.2) eV. X-ray diffraction revealed that the TiO2 films consisted of polycrystalline grains of size ≈ 100 nm.
Conductivity change of defective graphene by helium ion beams
Authors: Naitou Yuichi , Ogawa Shinichi
Published: April 2017

Applying a recently developed helium ion microscope, we demonstrated direct nano-patterning and Anderson localization of single-layer graphene (SLG) on SiO2/Si substrates. In this study, we clarified the spatial-resolution-limitation factor of direct nano-patterning of SLG. Analysis of scanning capacitance microscopy measurements reveals that the conductivity of helium ion (H+)-irradiated SLG nanostructures depends on their geometrical size, i.e., the smaller the H+-irradiated SLG region, the higher its conductivity becomes. This finding can be explained by the hopping carrier transport across strongly localized states of defective SLG.
Stylosanthes cv. Campo Grande silage and concentrate levels in diets for beef cattle
Authors: da Silva T. C. , Pereira O. G. , Martins R. M. , Agarussi M. C. N. , da Silva L. D. , Rufino L. D. A. , Filho S. C. Valadares , Ribeiro K. G.
Published: April 2017

The objective of this study was to evaluate the ruminal and intestinal digestion, the ruminal fermentation and the performance of beef cattle fed diets containing Stylosanthes silage (StS) and corn silage (CS). The treatments consisted of diets containing StS with different concentrate levels, based on dry matter (DM) (g/kg): 200 (StS-200), 400 (StS-400), 60 (StS-600), and a Control treatment with 600 g/kg CS and 400 g/kg concentrate (CS-400). In Experiment 1, 32 Nellore bulls, 364.28 ± 2.82 kg bodyweight, were distributed in a complete randomised design with eight replicates. Four Holstein × Zebu bulls (average bodyweight of 429 ± 15 kg) were used in Experiment 2, distributed in a 4 × 4 Latin square design. Nutrient intake was similar between StS-400 and CS-400 (P > 0.05), however, only StS-600 showed the same intake of total digestible nutrients as CS-400 (P < 0.05). Only the animals fed the StS-600 diet had similar (P > 0.05) average daily gain of carcass in comparison with those fed the Control diet. The StS-200 and StS-400 diets showed lower (P < 0.05) total tract digestibility of DM and crude protein than CS-400 (P < 0.05). Ruminal pH values of StS-200 and SE-400 were higher (P < 0.05) than in CS-400. The StS-600 diet showed a similar productive performance to CS in diets with 600 g/kg of concentrate, highlighting the potential use of this legume in diets for beef cattle in tropical conditions.
Production responses in young bulls fed glycerin as a replacement for concentrates in feedlot diets
Authors: de. Barros A. C. B. , Neiva J. N. M. , Restle J. , Missio R. L. , Miotto F. R. C. , Elejalde D. A. G. , Maciel R. P.
Published: April 2017

We assessed the productive performance, blood parameters, and carcass characteristics of young crossbreed dairy bulls kept in feedlots and fed with diets containing 0, 60, 120, and 240 g/kg of crude glycerin, replacing a mixture of ground pearl millet grain (50%) and babassu mesocarp bran (50%). Twenty-four bulls with an average age of 24 months and an average initial weight of 390 ± 31.5 kg were used. The experimental design was completely randomised with six replications. Dry matter and digestible energy intake were not influenced by diets. Feed conversion linearly decreased with increasing glycerin levels. The increase in the levels of glycerin resulted in a linear increase in blood glucose and in average daily weight gain. Carcass weight was not affected, but trimming fat increased and carcass yield decreased linearly, with increasing glycerin levels. The addition of crude glycerin at levels up to 240 g/kg of dry matter to diets containing babassu mesocarp bran and ground pearl millet grain increased the performance of young feedlot bulls, and improved feed efficiency and carcass subcutaneous fat thickness.
A phytosociological analysis of Butia yatay (Arecaceae) palm groves and gallery forests in Entre Rios, Argentina
Authors: Rodriguez Estela E. , Aceñolaza Pablo G. , Perea Eliana Linares , Galán de Mera Antonio
Published: April 2017

Multivariate floristic analyses of Butia yatay palm groves and gallery forest associated with the Uruguay River basin of Entre Rios Province (Argentina) were performed, including vegetation stands of Rio Grande do Sul State (Brazil). Several new phytosociological associations were identified. These include Eugenio myrcianthis–Butietum yatay association, which represents palm groves on sandy soils evolved from ancient river deposits, and Bignonio callistegioidis–Terminalietum australis association, which represents some gallery forests on regular floodplains of the Uruguay River. Both are placed in the new Pampean alliance Guettardo uruguensis–Bution yatay, which is part of the Dyckio brevifoliae–Terminalietalia australis order and Sebastianio schottiae–Terminalietea australis class, which has been described for Brazil.
Construction of Z-Scheme Bi2WO6/g-C3N4 Heterojunction Photocatalysts with Enhanced Visible-Light Photocatalytic Activity
Authors: Zhang Chunjiao , Li Rong , Zhao Yu , Wang Mei
Published: April 2017

Highly efficient visible-light-induced Z-scheme Bi2WO6/g-C3N4 heterojunction photocatalysts were synthesised by means of a simple hydrothermal method. The prepared Bi2WO6/g-C3N4 composite materials were characterised by means of X-ray diffraction, UV-vis diffuse reflectance spectroscopy, scanning electron microscopy, transmission electron microscopy, and photoluminescence. The photocatalytic activity of the Bi2WO6/g-C3N4 composite materials was determined through the degradation of Rhodamine B (RhB) solution as a target pollutant. The results of the experiment revealed that the active species O2•− and h+ play a crucial role in the scavenging system. The Bi2WO6/g-C3N4 composites showed an obviously improved photocatalytic performance compared with pure g-C3N4 and Bi2WO6 in the RhB degradation under visible light irradiation. The 10 wt-% Bi2WO6/g-C3N4 displayed the highest photocatalytic activity, and could completely degrade RhB within 75 min. It gave a reaction rate constant of 0.0439 min−1, which is 5.22 and 2.58 times higher than pure Bi2WO6 and g-C3N4, respectively. The intimate contact interface between the Bi2WO6 and g-C3N4 leads to effective separation of charge carriers and hinders the recombination efficiency of electrons and holes. Hence the photocatalytic activities of the Bi2WO6/g-C3N4 composite materials are significantly improved.
Evaluation and application of a targeted SPE-LC-MS method for quantifying plant hormones and phenolics in Arabidopsis
Authors: Guérard Florence , de Bont Linda , Gakière Bertrand , Tcherkez Guillaume
Published: April 2017

Application of metabolomics techniques to plant physiology is now considerable, and LC-MS is often being used for non-targeted, semi-quantitative analysis of effects caused by mutations or environmental conditions. However, examination of signalling metabolites like hormones require absolute rather than semi-quantitative quantitation, since their effect in planta is strongly dependent upon concentration. Further, plant hormones belong to different chemical classes and thus simultaneous quantitation remains highly challenging. Here we present an LC-MS method that allows the simultaneous absolute quantitation of six hormone families as well as selected phenolics. The technique requires solid phase extraction with a sulfonated cation exchange phase before analysis, and use calibration curves instead of isotopically labelled standards, which are indeed not commercially available for many hormonal molecules. The use of the total signal (including adducts) rather than a single quantifying mass appears to be crucial to avoid quantification errors because the ion distribution between adducts is found to be concentration-dependent. The different hormones considered appear to have contrasted ionisation efficiency due to their physical properties. However, the relatively low variability and the satisfactory response to standard additions show that the technique is accurate and reproducible. It is applied to Arabidopsis plants subjected to water stress, using either the wild-type or lines with altered NAD biosynthesis causing changes in salicylate signalling and phenylpropanoid levels. As expected, analyses show an increase in abscisic acid upon water stress and a consistent modification of phenolic compounds (including salicylate) in mutants.
Beer: old’s now new again
Authors: Rogers Peter
Published: April 2017

In the ‘Executive Style' section of a recent edition1 of The Age newspaper there was a list of the top 100 craft beers in 2016. That’s a ranking out of 300 or more national craft beers. The craft boom is driving a renewal in technical training, career opportunities and a deeper understanding of the underlying scientific basis of traditional brewing approaches.
Endogenous lysophosphatidic acid participates in vascularisation and decidualisation at the maternal–fetal interface in the rat
Authors: Sordelli Micaela S. , Beltrame Jimena S. , Zotta Elsa , Gomez Natalia , Dmytrenko Ganna , Sales María Elena , Blois Sandra M. , Davio Carlos , Martinez Silvina Perez , Franchi Ana M. , Ribeiro María L.
Published: April 2017

Lysophosphatidic acid (LPA) affects several female reproductive functions through G-protein-coupled receptors. LPA contributes to embryo implantation via the lysophospholipid LPA3 receptor. In the present study we investigated the participation of endogenous LPA signalling through the LPA3 receptor in vascularisation and decidualisation, two crucial events at the maternal–fetal interface. Pregnant rats were treated with diacylglycerol pyrophosphate (DGPP), a highly selective antagonist of LPA3 receptors, on Day 5 of gestation. Pregnant rats received intrauterine (i.u.) injections of single doses of DGPP (0.1 mg kg−1) in a total volume of 2 μL in the left horn (treated horn) in the morning of GD5. DGPP treatment produced aberrant embryo spacing and increased embryo resorption. The LPA3 receptor antagonist decreased the cross-sectional length of the uterine and arcuate arteries and induced histological anomalies in the decidua and placentas. Marked haemorrhagic processes, infiltration of immune cells and tissue disorganisation were observed in decidual and placental tissues from sites of resorption. The mRNA expression of three vascularisation markers, namely interleukin 10 (Il10), vascular endothelial growth factor (Vegfa) and vascular endothelial growth factor receptor 1 (Vegfr1), was reduced at sites of resorption from Day 8. The results show that the disruption of endogenous LPA signalling by blocking the LPA3 receptor modified the development of uterine vessels with consequences in the formation of the decidua and placenta and in the growth of embryos.
Spatial scales influence long-term response of herbivores to prescribed burning in a savanna ecosystem
Authors: Kimuyu Duncan M. , Sensenig Ryan L. , Chira Robert M. , Githaiga John M. , Young Truman P.
Published: April 2017

Both wild and prescribed fire in savanna ecosystems influence habitat use by herbivores by creating or maintaining spatial and temporal heterogeneity in forage quality and vegetation cover. Yet little is known about how spatial scales influence long-term persistence of fire effects. We examined changes over a 6-year period in herbivore preference for experimentally burned patches that varied in spatial extent and grain. Avoidance for the burns by elephants and preference for the burns by impala and Grant’s gazelle decreased significantly. For the rest of the species (zebra, eland, oryx, hartebeest, warthog and hare), there were no significant changes in preference for the burns. Changes in preference for the burned areas depended on the spatial extent and grain of the burn, with intermediate-size (9-ha) burns and large (8-ha) patchy burns being more preferred 6–7 years after fire. Grain, but not the spatial extent of the burned area, influenced changes in grass height. Fire resulted in a delayed reduced tree density irrespective of the spatial scale of the burn. Results of this study indicate that, depending on the scale of fire prescription, the impacts of fire on herbivores may last longer than previous studies suggest.
Air quality policy and fire management responses addressing smoke from wildland fires in the United States and Australia
Authors: Hyde Joshua C. , Yedinak Kara M. , Talhelm Alan F. , Smith Alistair M. S. , Bowman David M. J. S. , Johnston Fay H. , Lahm Peter , Fitch Mark , Tinkham Wade T.
Published: April 2017

Wildland fire emissions degrade air quality and visibility, having adverse economic, health and visibility impacts at large spatial scales globally. Air quality regulations can constrain the goals of landscape resilience and management of fire-dependent ecosystems. Here, we review the air quality regulatory framework in the United States, comparing this framework with that of Australia. In the United States, wildland fire management and air quality policies have evolved independently, yet interact to meet diverse public needs. Australian policy development is more recent and decentralised. We find that (1) for maxiumum effectiveness, smoke and fire regulatory frameworks must keep pace with scientific evidence, environmental and social change, and be accompanied by clear regulatory guidance; (2) episodic, non-stationary qualities of fire, and its role in ecosystems, pose specific challenges to regulators and policy-makers; and (3) the complexity of industry-focused air quality policies often leads to unintended consequences for fire management. More research is needed to create and implement more effective fire and air policies and better prepare social-ecological systems to address the challenges of climate change mitigation. These insights may be helpful for countries initially developing complementary fire and air policies, especially as the role of fire becomes more important geopolitically and globally.
Quantitative criticism of literary relationships
Authors: Dexter Joseph P. , Katz Theodore , Tripuraneni Nilesh , Dasgupta Tathagata , Kannan Ajay , Brofos James A. , Bonilla Lopez Jorge A. , Schroeder Lea A. , Casarez Adriana , Rabinovich Maxim , Haimson Lushkov Ayelet , Chaudhuri Pramit
Published: April 2017

Significance

Famous works of literature can serve as cultural touchstones, inviting creative adaptations in subsequent writing. To understand a poem, play, or novel, critics often catalog and analyze these intertextual relationships. The study of such relationships is challenging because intertextuality can take many forms, from direct quotation to literary imitation. Here, we show that techniques from authorship attribution studies, including stylometry and machine learning, can shed light on inexact literary relationships involving little explicit text reuse. We trace the evolution of features not tied to individual words across diverse corpora and provide statistical evidence to support interpretive hypotheses of literary critical interest. The significance of this approach is the integration of quantitative and humanistic methods to address aspects of cultural evolution.
Effects of systemic multiexon skipping with peptide-conjugated morpholinos in the heart of a dog model of Duchenne muscular dystrophy
Authors: Echigoya Yusuke , Nakamura Akinori , Nagata Tetsuya , Urasawa Nobuyuki , Lim Kenji Rowel Q. , Trieu Nhu , Panesar Dharminder , Kuraoka Mutsuki , Moulton Hong M. , Saito Takashi , Aoki Yoshitsugu , Iversen Patrick , Sazani Peter , Kole Ryszard , Maruyama Rika , Partridge Terry , Takeda Shin’ichi , Yokota Toshifumi
Published: April 2017

Significance

Duchenne muscular dystrophy (DMD) is a lethal genetic disorder caused by a lack of dystrophin protein. Cardiomyopathy is a leading cause of death in DMD. Although exon skipping with antisense morpholino oligonucleotides is very promising, morpholino-mediated exon skipping has induced barely detectable dystrophin levels in the hearts of DMD animal models. Here, we show that systemic multiexon skipping using a cocktail of peptide-conjugated morpholinos (PPMOs) rescued dystrophin expression in the myocardium and cardiac Purkinje fibers in a dystrophic dog model. The treatment reduced vacuole degeneration in Purkinje fibers and improved electrocardiogram abnormalities without apparent toxicity. These results indicate that PPMO-mediated multiexon skipping is a therapeutic approach for treating cardiac conduction abnormalities in DMD.
Unraveling the disease consequences and mechanisms of modular structure in animal social networks
Authors: Sah Pratha , Leu Stephan T. , Cross Paul C. , Hudson Peter J. , Bansal Shweta
Published: April 2017

Significance

Modular organization in animal social networks is hypothesized to alleviate the cost of disease burden in group-living species. However, our analysis of empirical social networks of 43 animal species along with theoretical networks demonstrates that infectious disease spread is largely unaffected by the underlying modular organization, except when social networks are extremely subdivided. We show that high fragmentation and high subgroup cohesion, which are both associated with high modularity in social networks, induce structural delay and trapping of infections that spread through these networks, reducing disease burden. We validate our results using real animal social networks and recommend the use of appropriate null network models when data-limited estimates of epidemic consequences are necessary.
Parathyroid hormone controls paracellular Ca
2+
transport in the thick ascending limb by regulating the tight-junction protein Claudin14
Authors: Sato Tadatoshi , Courbebaisse Marie , Ide Noriko , Fan Yi , Hanai Jun-ichi , Kaludjerovic Jovana , Densmore Michael J. , Yuan Quan , Toka Hakan R. , Pollak Martin R. , Hou Jianghui , Lanske Beate
Published: April 2017

Significance

Renal calcium reabsorption is a critical process for maintaining systemic calcium homeostasis. Although the role of parathyroid hormone (PTH) in the regulation of transcellular Ca
2+
reabsorption in distal convoluted tubules is well understood, its potential role in controlling the paracellular Ca
2+
transport in the thick ascending limb of Henle (TAL) has not been investigated. We now present data demonstrating that PTH/PTHrP receptor (PTH1R) signaling directly and indirectly controls the levels of Claudin14 (CLDN14), a tight-junction protein responsible for paracellular Ca
2+
transport in the TAL. Our findings suggest that down-regulation of Claudin14 could provide a potential treatment option to correct urinary Ca
2+
loss, particularly in patients with hypoparathyroidism.
Providing driver’s licenses to unauthorized immigrants in California improves traffic safety
Authors: Lueders Hans , Hainmueller Jens , Lawrence Duncan
Published: April 2017

Significance

Several states have experimented with more inclusive policies toward immigrants. There is little empirical evidence related to their impact. Our study examines the short-term traffic safety effects of one of the largest-scale state policies focused on the integration of unauthorized immigrants: California’s extension of driving privileges to unauthorized immigrants. We find that this policy did not increase the total number of accidents or the occurrence of fatal accidents, but it did reduce the likelihood of hit and run accidents, thereby improving traffic safety and reducing costs for California drivers. Our findings have important implications for policymakers: providing unauthorized immigrants with access to driver’s licenses can create positive externalities for the communities in which they live.