bluuebunny/crossref_metadata_2025 huggingface dataset:
Sulodexide versus Control and the Risk of Thrombotic and Hemorrhagic Events: Meta-Analysis of Randomized Trials
Authors: Bikdeli Behnood , Chatterjee Saurav , Kirtane Ajay J. , Parikh Sahil A. , Andreozzi Giuseppe M. , Desai Nihar R. , Francese Dominic P. , Gibson C Michael , Piazza Gregory , Goldhaber Samuel Z. , Eikelboom John W. , Krumholz Harlan M. , Stone Gregg W.
Published: October 2020

Thrombotic cardiovascular disease (myocardial infarction [MI], stroke, and venous thromboembolism [VTE]) remains a major cause of death and disability. Sulodexide is an oral glycosaminoglycan containing heparan sulfate and dermatan sulfate. We conducted a systematic review and meta-analysis to determine the cardiovascular efficacy, and safety of sulodexide versus control in randomized controlled trials (RCTs). We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials for RCTs reporting cardiovascular outcomes in patients receiving sulodexide versus control (placebo or no treatment). Outcomes included all-cause mortality, cardiovascular mortality, MI, stroke, deep vein thrombosis (DVT), pulmonary embolism, and bleeding. We used inverse variance random-effects models with odds ratio (OR) as the effect measure. After screening 360 records, 6 RCTs including 7,596 patients (median follow-up duration: 11.6 months) were included. Patients were enrolled for history of MI, VTE, peripheral arterial disease, or cardiovascular risk factors plus nephropathy. Use of sulodexide compared with control was associated with reduced odds of all-cause mortality (OR 0.67, 95% confidence interval [CI] 0.52–0.85, p = 0.001), cardiovascular mortality (OR 0.44, 95% CI 0.22–0.89, p = 0.02), and MI (OR 0.70, 95% CI 0.51–0.96, p = 0.03), and nonsignificantly reduced odds of stroke (OR 0.78, 95% CI 0.45–1.35, p = 0.38). Sulodexide was associated with significantly reduced odds of VTE (OR 0.44, 95% CI 0.24–0.81, p = 0.008), including DVT (OR 0.41, 95% CI 0.26–0.65, p < 0.001), but not pulmonary embolism (OR 0.92, 95% CI 0.40–2.15, p = 0.86). Bleeding events were not significantly different in the two groups (OR 1.14, 95% CI 0.47–2.74, p = 0.48). In six RCTs across a variety of clinical indications, use of sulodexide compared with placebo or no treatment was associated with reduced odds of all-cause mortality, cardiovascular mortality, MI, and DVT, without a significant increase in bleeding. Additional studies with this agent are warranted.
Evaluation of 2% Chlorhexidine and 2% Sodium Fluoride as Endodontic Irrigating Solutions on Root Dentine Microhardness: An In Vitro Study
Authors: Kulkarni Sangeeta , Mustafa Mohammed , Ghatole Kiran , AlQahtani Ali Robaian , I. Asiri Faris Yahya , Alghomlas Ziyad Ibrahim , Alothman Tameem Abdullah , Alhajri Fawaz Fahad
Published: October 2020

Objectives The aim of this study was to evaluate the effects of 2% chlorhexidine gluconate (CHG) and 2% sodium fluoride (NaF) as endodontic irrigants on microhardness of root dentin.

Materials and Methods In this in vitro study, access cavity and root canal preparations were done on 24 freshly extracted anterior teeth. After sectioning into 24 dentin discs using hard tissue microtome in 2 mm thickness, all samples were immersed in solutions of 17% ethylenediamine tetra-acetic acid (EDTA) (2 minutes) followed by 2.5% of sodium hypochlorite (NaOCl) (10 minutes). Then samples were randomly divided into three groups based on the irrigant used: Group I: saline (control group); Group II: 2% NaF; Group III: 2% CHG for two minutes each. Dentin microhardness was measured before (pretreatment), during (after treatment with 17% EDTA and 2.5% NaOCl), and after the experimental period (after treatment with saline, 2% NaF, and 2% CHG) using a Vickers indenter. Statistical evaluation of the data was done using one-way analysis of variance (ANOVA) and the Student’s t-test, and the values are tabulated.

Results Specimens rinsed in 2% CHG showed a significant increase in Vickers hardness number (VHN) values (p < 0.05), as compared with EDTA and NaOCl groups, whereas saline and 2% NaF groups showed no significant difference.

Conclusions NaF did not show any significant effect on microhardness of the root dentin. CHG as an irrigant was seen to have a strengthening effect on dentin microhardness in comparison to NaOCl and EDTA, which has decreased the strength of root dentin.
Synthesis of Open-Cage Fullerenes with a Long Tail
Authors: Zhang Hao , Su Jie , Gan Liangbing
Published: October 2020

To explore potential applications for open-cage fullerenes, we employed 4-((6-bromohexyl)oxy)aniline to react with an open-cage fullerene precursor which has an 11-membered orifice and prepared open-cage fullerenes with an 18-membered orifice. The bromo atom at the end of the hexyl chain in these open-cage compounds could be easily replaced by alkoxyl groups to further extend the linear chain. The results also show that the presence of the alkyl chain slightly changes the reactivity of the orifice-expansion reaction.
Interpreting public policy dilemmas: discourse analytical insights
Authors: Wash Ian
Published: October 2020

This article explains the value of discourse analysis for interpreting the construction and resolution of policy dilemmas in the field of international education. Its case material is drawn from official documents relating to international education policy, published by global bodies such as the United Nations and World Bank from 2000 to 2018, explored with two purposes in mind. The first is empirical, the analysis revealing how a dominant ‘liberal’ model governing international education was discursively constructed as a grand narrative about the purpose and intended outcomes in international education. This is achieved by applying an interpretive discourse analytical approach, customised for this particular policy puzzle, to the international education corpus. The article’s second purpose is methodological, to reflect on the various criticisms and supposed limitations of using discourse analysis as a tool of public policy analysis. This part of the article argues that the discourse approach can equip analysts with a reliable tool-kit for carrying out research into the subtle and often unrecognised ways in which ideas and beliefs inform global education policy practices. A systematic discourse analysis reveals the tensions and sometimes conflicting meanings that elite decision-makers possess about international education. Ultimately, it is argued that the discourse approach can offer both empirical insights and a range of policy recommendations from a discourse analysis that destabilises the dominant ‘liberal’ narrative about international education in the relevant documents.
The energy spectrum of reconnected vortex loops in He II
Authors: Andryushchenko V. A. , Kondaurova L. P.
Published: October 2020

The energy spectrum after reconnection of vortex loops at various temperatures of liquid (from a temperature close to absolute zero to T = 1.9 K) has been systematically studied. Initial conditions were varied at each temperature: the vortex loops were initially located in planes, the angle between which varied from 0 to π/2. A statistical approach was used to find the spectrum: the second-order longitudinal structure function of the velocity was calculated. In all the cases considered, the spectra E(k) ∝ (k)−3/2 were obtained, which are typical of a smooth vortex ring.
Photoluminescence of Tl4HgI6 single crystals
Authors: Kashuba A. I. , Solovyov M. V. , Franiv A. V. , Andriyevsky B. , Malyi T. S. , Tsyumra V. B. , Zhydachevskyy Ya. A. , Ilchuk H. A. , Fedula M. V.
Published: October 2020

The temperature behavior of Tl4HgI6 photoluminescence spectra is presented. The emission spectra are studied in the temperature range between 4.5 and 300 K and in the spectral range 350–650 nm. Two main emission bands at ∼551 nm and ∼448 nm are observed corresponding to the emissions of HgI2 and Tll impurity centers. It is assumed that the low-temperature emission band at ∼520 nm corresponds to the recombination of the exciton. The luminescence peaks observed in emission spectra in the range between 350 and 410 nm correspond to the phonon repetitions. The excitation spectra of emission bands are measured at 4.5 K and compared with the electron density of states.
The sign-changing solutions and ground states for planar Schrödinger–Newton system with an exponential critical growth
Authors: Wang Wenbo , Li Quanqing , Li Yongkun
Published: October 2020

In this paper, we study the planar Schrödinger–Newton system with a Coulomb potential where the nonlinearity is super-linear at zero and exponential critical at infinity. With a weaker condition than the Nehari type monotonic condition, we obtain a least-energy sign-changing solution via the variational method. Moreover, we obtain the existence of ground states, and the energy of any nodal solution is strictly larger than two times the least energy. We also give some convergence properties of the ground states.
Impact of spatiotemporal smoothing on the two-plasmon–decay instability
Authors: Turnbull D. , Maximov A. V. , Cao D. , Christopherson A. R. , Edgell D. H. , Follett R. K. , Gopalaswamy V. , Knauer J. P. , Palastro J. P. , Shvydky A. , Stoeckl C. , Wen H. , Froula D. H.
Published: October 2020

Higher levels of hot electrons from the two-plasmon–decay instability are observed when smoothing by spectral dispersion (SSD) is turned off in directly driven inertial confinement fusion experiments at the Omega Laser Facility. This finding is explained using a hot-spot model based on speckle statistics and simulation results from the laser–plasma simulation environment. The model accurately reproduces the relative increase in hot-electron activity at two different drive intensities although it slightly overestimates the absolute number of hot electrons in all cases. Extrapolating from the current ≈360-GHz system while adhering to the logic of the hot-spot model suggests that a larger SSD bandwidth should significantly mitigate hot-electron generation, and legacy 1-THz OMEGA experiments appear to support this conclusion. These results demonstrate that it is essential to account for laser speckles and spatiotemporal smoothing to obtain quantitative agreement with experiments. A compilation of hot-electron data from the past two decades reveals several other important points: (1) many prior experiments are more easily understood using recent results from multibeam absolute instability theory and (2) experiments with ignition-scale conditions produce less hot electrons compared to OMEGA spherical experiments for a given vacuum overlapped intensity, which is a promising result for validating performance predictions based on hydrodynamic scaling relations.
Effect of constant-DI pacing on single cell pacing dynamics
Authors: Parthiban P. , Newell S. , Tolkacheva E. G.
Published: October 2020

Cardiac alternans, beat-to-beat alternations in action potential duration, is a precursor to fatal arrhythmias such as ventricular fibrillation. Previous research has shown that voltage driven alternans can be suppressed by application of a constant diastolic interval (DI) pacing protocol. However, the effect of constant-DI pacing on cardiac cell dynamics and its interaction with the intracellular calcium cycle remains to be determined. Therefore, we aimed to examine the effects of constant-DI pacing on the dynamical behavior of a single-cell numerical model of cardiac action potential and the influence of voltage–calcium (V–Ca) coupling on it. Single cell dynamics were analyzed in the vicinity of the bifurcation point using a hybrid pacing protocol, a combination of constant-basic cycle length (BCL) and constant-DI pacing. We demonstrated that in a small region beneath the bifurcation point, constant-DI pacing caused the cardiac cell to remain alternans-free after switching to the constant-BCL pacing, thus introducing a region of bistability (RB). The size of the RB increased with stronger V–Ca coupling and was diminished with weaker V–Ca coupling. Overall, our findings demonstrate that the application of constant-DI pacing on cardiac cells with strong V–Ca coupling may induce permanent changes to cardiac cell dynamics increasing the utility of constant-DI pacing.
An improved path-integral method for golden-rule rates
Authors: Lawrence Joseph E. , Manolopoulos David E.
Published: October 2020

We present a simple method for the calculation of reaction rates in the Fermi golden-rule limit, which accurately captures the effects of tunneling and zero-point energy. The method is based on a modification of the recently proposed golden-rule quantum transition state theory (GR-QTST) of Thapa, Fang, and Richardson [J. Chem. Phys. 150, 104107 (2019)]. While GR-QTST is not size consistent, leading to the possibility of unbounded errors in the rate, our modified method has no such issue and so can be reliably applied to condensed phase systems. Both methods involve path-integral sampling in a constrained ensemble; the two methods differ, however, in the choice of constraint functional. We demonstrate numerically that our modified method is as accurate as GR-QTST for the one-dimensional model considered by Thapa and co-workers. We then study a multidimensional spin-boson model, for which our method accurately predicts the true quantum rate, while GR-QTST breaks down with an increasing number of boson modes in the discretization of the spectral density. Our method is able to accurately predict reaction rates in the Marcus inverted regime without the need for the analytic continuation required by Wolynes theory.
Optical absorption window in Na3Bi based three-dimensional Dirac electronic system
Authors: Li Q. N. , Xu W. , Xiao Y. M. , Ding L. , Van Duppen B. , Peeters F. M.
Published: October 2020

We present a detailed theoretical study of the optoelectronic properties of a Na3Bi based three-dimensional Dirac electronic system (3DDES). The optical conductivity is evaluated using the energy-balance equation derived from a Boltzmann equation, where the electron Hamiltonian is taken from a simplified k⋅p approach. We find that for short-wavelength irradiation, the optical absorption in Na3Bi is mainly due to inter-band electronic transitions. In contrast to the universal optical conductance observed for graphene, the optical conductivity for Na3Bi based 3DDES depends on the radiation frequency but not on temperature, carrier density, and electronic relaxation time. In the radiation wavelength regime of about 5μm<λ<200 μm, an optical absorption window is found. This is similar to what is observed in graphene. The position and width of the absorption window depend on the direction of the light polarization and sensitively on temperature, carrier density, and electronic relaxation time. Particularly, we demonstrate that the inter-band optical absorption channel can be switched on and off by applying the gate voltage. This implies that similar to graphene, Na3Bi based 3DDES can also be applied in infrared electro-optical modulators. Our theoretical findings are helpful in gaining an in-depth understanding of the basic optoelectronic properties of recently discovered 3DDESs.
Confirming the role of nuclear tunneling in aqueous ferrous–ferric electron transfer
Authors: Lawrence Joseph E. , Manolopoulos David E.
Published: October 2020

We revisit the well-known aqueous ferrous–ferric electron transfer reaction in order to address recent suggestions that nuclear tunneling can lead to significant deviation from the linear response assumption inherent in the Marcus picture of electron transfer. A recent study of this reaction by Richardson and co-workers [Phys. Chem. Chem. Phys. 22, 10687 (2020)] has found a large difference between their new path-integral method, golden-rule quantum transition state theory (GR-QTST), and the saddle point approximation of Wolynes (Wolynes theory). They suggested that this difference could be attributed to the existence of multiple tunneling pathways, leading Wolynes theory to significantly overestimate the rate. This was used to argue that the linear response assumptions of Marcus theory may break down for liquid systems when tunneling is important. If true, this would imply that the commonly used method for studying such systems, where the problem is mapped onto a spin-boson model, is invalid. However, we have recently shown that size inconsistency in GR-QTST can lead to poor predictions of the rate in systems with many degrees of freedom. We have also suggested an improved method, the path-integral linear golden-rule (LGR) approximation, which fixes this problem. Here, we demonstrate that the GR-QTST results for ferrous–ferric electron transfer are indeed dominated by its size consistency error. Furthermore, by comparing the LGR and Wolynes theory results, we confirm the established picture of nuclear tunneling in this system. Finally, by comparing our path-integral results to those obtained by mapping onto the spin-boson model, we reassess the importance of anharmonic effects and the accuracy of this commonly used mapping approach.
Axilenses: Refractive micro-optical elements with arbitrary exponential profiles
Authors: Gorelick Sergey , Paganin David M. , de Marco Alex
Published: October 2020

We report on the experimental demonstration of refractive micro-optical elements with arbitrary exponential surface profiles. Refractive optical elements such as lenses and axicons have parabolic (power-exponent of two) or conical (power-exponent of one) surface profiles, respectively. Here, we analyze micro-optical elements with non-parabolic surface profiles characterized by both integer and fractional power-exponents between 0.5 and 3.25. The experimentally measured beam shaping properties of the components were compared with numerical simulations and shown to be in excellent agreement. The generalized family of optical elements with non-parabolic power-exponent elements allows variation of the optical performance within the same device form-factor and enhancement of various optical properties, such as the extension of the depth-of-focus or resolution improvement.
Rayleigh analysis and dielectric dispersion in polycrystalline 0.5(Ba0.7Ca0.3)TiO3–0.5Ba(Zr0.2Ti0.8)O3 ferroelectric thin films by domain-wall pinning element modeling
Authors: Becker M. , Burkhardt C. J. , Schröppel B. , Kleiner R. , Koelle D.
Published: October 2020

We use impedance spectroscopy to investigate the dielectric response in polycrystalline, lead-free 0.5(Ba0.7Ca0.3)TiO3–0.5Ba(Zr0.2Ti0.8)O3 (BCZT) ferroelectric thin films as a function of amplitude E0 and frequency f of an applied ac electric field. Impedance spectra from f=10 Hz to 1 MHz were collected at different E0 on polycrystalline BCZT capacitor stacks, grown by pulsed laser deposition on platinized Si substrates and covered with Au electrodes. Deconvolution of the spectra is achieved by fitting the measured impedance to the impedance of an equivalent-circuit model of the capacitor stacks, including a recently proposed domain-wall pinning element ZDW. From an extended data analysis, we quantify the coupling strength between dielectric nonlinearity and frequency dispersion in the BCZT thin films, and we obtain a schematic diagram of the different domain-wall-motion regimes. Our results indicate that the presence of grain boundaries in BCZT reduces the coupling strength and suppresses the motion of internal domain-wall segments and also the irreversible center-of-mass motion of the domain walls.
Piezoelectric-driven uniaxial pressure cell for muon spin relaxation and neutron scattering experiments
Authors: Ghosh Shreenanda , Brückner Felix , Nikitin Artem , Grinenko Vadim , Elender Matthias , Mackenzie Andrew P. , Luetkens Hubertus , Klauss Hans-Henning , Hicks Clifford W.
Published: October 2020

We present a piezoelectric-driven uniaxial pressure cell that is optimized for muon spin relaxation and neutron scattering experiments and that is operable over a wide temperature range including cryogenic temperatures. To accommodate the large samples required for these measurement techniques, the cell is designed to generate forces up to ∼1000 N. To minimize the background signal, the space around the sample is kept as open as possible. We demonstrate here that by mounting plate-like samples with epoxy, a uniaxial stress exceeding 1 GPa can be achieved in an active volume of at least 5 mm3. We show that for practical operation, it is important to monitor both the force and displacement applied to the sample. In addition, because time is critical during facility experiments, samples are mounted in detachable holders that can be rapidly exchanged. The piezoelectric actuators are likewise contained in an exchangeable cartridge.
High-efficiency narrow-band plasmonic hot electron conversion from nanoscale sodium–silicon heterostructures
Authors: Wen Long , Li Jiaxiang , Dong Yajin , Lou Zaizhu , Chen Qin
Published: October 2020

Plasmonic harvesting of hot electrons has stimulated intensive research activities for applications ranging from sub-bandgap photodetection to photocatalysis. Both high photoelectric conversion efficiency and tunable spectral response are pursued by manipulating resonant metal–semiconductor (M–S) nanostructures. Although noble plasmonic metals have been exclusively employed in hot electron conversion studies, exploring new materials may offer an additional degree of freedom to manipulate the hot electron generation, transport, and emission processes. In this paper, we propose to employ the low-loss alkali metal sodium as an alternate plasmonic material for developing a narrow-band resonant hot electron device. Based on a backside-illumination (BSI) configuration where plasmonic hot electrons generate locally at the M–S interface, the transport loss can be significantly suppressed. Thanks to its ultralow imaginary part of the permittivity, bringing Na into the BSI design allows for efficient shrinking of the resonant linewidth down to sub-20 nm. Another intriguing feature is that Na has more preferred electron density of state distribution for facilitating hot electron emission at the M–S junction. The optimized Na BSI device can yield a photocurrent responsivity up to 50 mA/W at a wavelength of 1400 nm as predicted by our electromagnetic simulation and theoretical model. Our study highlights that the alkali metal could be a promising alternative material for the development of high-Q resonant hot electron devices for near-infrared wavelengths.
A specially-designed electrostatic sensor for the condition monitoring of rolling bearings
Authors: Li Lin , Hu Hongli , Tang Kaihao
Published: October 2020

Abstract

The electrostatic method is a rapidly growing research field in the monitoring of rotating equipment. This article reports how a specially-designed integrated electrostatic sensor was utilized to monitor the working conditions of rolling bearings. We firstly analyzed the principle and mathematic modeling of inner current noise generated by cable vibration and deformation. To ensure the electrostatic monitoring avoided being affected by cable vibration and deformation, we designed a ring-shaped printed circuit board to integrate the electrostatic electrode and condition unit together, which can be mounted tightly beside the rolling bearings; in this way, the cable connecting the electrode with the condition unit is removed and the distance between the electrode and rollers is shortened. Experiments using this integrated sensor board were conducted to obtain the electrostatic signals of working bearings. Time features were analyzed in detail to show the differences of four working bearings across the whole process. Experimental results show that the proposed integrated electrostatic sensor has a good performance in the electrostatic monitoring of rolling bearings.
Deep learning-based medical image segmentation with limited labels
Authors: Chi Weicheng , Ma Lin , Wu Junjie , Chen Mingli , Lu Weiguo , Gu Xuejun
Published: October 2020

Deep learning (DL)-based auto-segmentation has the potential for accurate organ delineation in radiotherapy applications but requires large amounts of clean labeled data to train a robust model. However, annotating medical images is extremely time-consuming and requires clinical expertise, especially for segmentation that demands voxel-wise labels. On the other hand, medical images without annotations are abundant and highly accessible. To alleviate the influence of the limited number of clean labels, we propose a weakly supervised DL training approach using deformable image registration (DIR)-based annotations, leveraging the abundance of unlabeled data. We generate pseudo-contours by utilizing DIR to propagate atlas contours onto abundant unlabeled images and train a robust DL-based segmentation model. With 10 labeled TCIA dataset and 50 unlabeled CT scans from our institution, our model achieved Dice similarity coefficient of 87.9%, 73.4%, 73.4%, 63.2% and 61.0% on mandible, left & right parotid glands and left & right submandibular glands of TCIA test set and competitive performance on our institutional clinical dataset and a third party (PDDCA) dataset. Experimental results demonstrated the proposed method outperformed traditional multi-atlas DIR methods and fully supervised limited data training and is promising for DL-based medical image segmentation application with limited annotated data.
Combined dual energy and iterative metal artefact reduction for PET/CT in head and neck cancer
Authors: Kovacs D G , Ladefoged C N , Berthelsen A K , Fischer B M , Andersen F L
Published: October 2020

Metal artefacts in PET/CT images hamper diagnostic accuracy in head and neck cancer (HNC). The aim of this study is to characterise the clinical effects of metal artefacts on PET/CT in HNC and to inform decision-making concerning implementation of MAR techniques. We study a combined dual energy CT and inpainting-based metal artefact reduction (DECT-I-MAR) technique for PET/CT in three settings: (A) A dental phantom with a removable amalgam-filled tooth to evaluate the PET error in comparison to a known reference. (B) PET-positive patients with metallic implants to demonstrate the relationship between CT metal artefacts and PET error. (C) Metabolic tumour volumes delineated in PET-positive patients with metal implants to evaluate the clinical impact. In (A) DECT-I-MAR reduced the PET error significantly. In (B) we demonstrate an increasing PET error with increasing CT artefact severity in patients. In (C) it is shown that the presence of artefacts in the same axial slices as the tumour significantly decreases biomarker stability and increase delineation variability. This work shows the practical feasibility of DECT-I-MAR-based PET/CT imaging, and indicates a positive clinical impact of using the technique routinely for HNC patients. The impact of CT artefacts on PET is considerable, especially in workflows where quantitative PET biomarkers and tumour volumes are used. In such cases, and for patients with tumours in proximity of metals, we recommend that a MAR technique for PET/CT is employed.
Omega transition accompanied by mechanically-induced twinned martensite
Authors: Du P J , Li Y J , Misra R D K , Wu D
Published: October 2020

We present here an analysis on omega transition process during martensitic transformation. Martensitic transformation occurred during deformation at room temperature, avoiding the influence of auto-tempering on metastable omega phase. Based on the crystallographic relationships of twinned crystals, the twin interface of twinned martensite was characterized by considering the effect of direction of incidence electron beam on diffraction patterns through pole figures. Omega phase only existed at the boundaries of twinned martensite with single variant. It was proposed that lattice invariant twin shear during the dynamic transformation of twinned martensite promoted the formation of omega phase.
Lanthanum and strontium modified bismuth ferrite based perovskites with ultra-narrow band gaps
Authors: Ning Huanpo , Yu Jian
Published: October 2020

The wide optical band gaps of ferroelectric perovskite oxides have restricted their light absorbing capacities in the photovoltaic devices. In this work, an ultra-narrow band gap E
g and wide optical absorption across the ultraviolet-visible-infrared sunlight spectrum was achieved in lanthanum and strontium atoms modified Bi(Fe, Mn)O3 perovskites by chemical substitution and defect engineering. XRD results show that the A and B site co-substituted samples are single phase. The XPS characterizations indicate the Fe ions are in the trivalent state for all the samples. The LM6 and SM6 samples exhibit an ultra-narrow band gap about 1.26 eV and 1.06 eV, respectively. The reduced E

g
was due to the defect states produced within the band gap, acting as a scaffold to give electrons to Fe 3d states and receive the electrons from O 2p states. Based on this research, these chemically modified BFO based perovskite could potentially extend its sunlight absorption deep into the infrared region.
An ultra-thin quad-band metamaterial inspired absorber using symmetric bent-arrow shaped resonator for sensing and imaging in defense applications
Authors: Singh Raghvenda Kumar , Gupta Ashish , Sharma Anand , Tyagi Utkarsh , Gupta Nishchay , Yadav Akash
Published: October 2020

In this paper, a novel compact quad-band polarization insensitive metamaterial absorber has been proposed to be employable in the microwave frequency regime. The unit-cell geometry comprises of four symmetric bent-arrow shaped resonators, where each arrow has been bounded by an open ring. The resultant structure is further surrounded by a closed ring to obtain an extra resonance band. Full-wave simulation with normal incidence depicts quad-band operation with absorption peaks at 3.24 GHz (S-band), 6.55 GHz (C-band), 15.22 GHz (Ku-Band), 15.94 GHz (Ku-band) and absorptivity levels of 99.57%, 99.94%, 96.10%, 98.65% correspondingly. It also shows full width half maximum (FWHM) bandwidth of 100 MHz, 200 MHz and 1210 MHz in the first, second and third bands respectively. Furthermore, the proposed structure is based on four-fold symmetry therefore exhibits polarization-insensitive behaviour unlike conventional absorbers. The structure is fabricated on 1 mm FR4 Glass Epoxy substrate equivalent to 0.0108 λ
0 hence, can be used as absorber coating for planar surfaces. The designed absorber has been fabricated and experimental results were in good agreement with the simulated responses enabling its wide application in various technologies like stealth technology, radar cross section reduction, anechoic chambers, electromagnetic interference/electromagnetic compatibility, and radio frequency identification.
OFM-recirculation and OFM-suction: advanced in-vivo open flow microperfusion (OFM) methods for direct and absolute quantification of albumin in interstitial fluid
Authors: Hummer Joanna , Schwingenschuh Simon , Raml Reingard , Boulgaropoulos Beate , Schwagerle Gerd , Augustin Thomas , Sinner Frank , Birngruber Thomas
Published: October 2020

Objective: To implement OFM-recirculation and OFM-suction capable of direct and absolute in-vivo quantification of albumin in the ISF of pigs. Approach: OFM-recirculation and OFM-suction were used to collect ISF in-vivo in pigs and lymph was collected from the same pigs after OFM sampling. Blood was collected before and after OFM sampling, plasma was isolated and mean albumin plasma concentrations per pig were used to yield albumin ISF-to-plasma ratios. We characterized the quality of the collected undiluted ISF via (1) stable albumin ISF-to-plasma ratio in OFM-recirculation and in OFM-suction samples, (2) comparison of albumin ISF-to-plasma ratios from OFM-recirculation and OFM-suction and (3) comparison of normalized albumin concentrations in the ISF and lymph. Main results: Both advanced OFM methods were successfully implemented and albumin was quantified from the collected ISF samples. OFM-recirculation reached stable albumin ISF-to-plasma ratios after 20 recirculation cycles. Absolute ISF albumin concentrations were 11.2 mg ml−1 (OFM-recirculation) and 14.2 mg ml−1 (OFM-suction). Albumin ISF-to-plasma ratios were 0.39 ± 0.04 (OFM -recirculation) and 0.47 ± 0.1 (OFM-suction). Significance: Knowledge of the ISF protein content is of major importance when assessing PK/PD effects, especially of highly protein bound drugs. Up to now, only blood albumin values have been available to determine the degree of protein binding in several tissues. OFM-recirculation and OFM-suction allow direct, absolute quantification of albumin in ISF for the first time and enable investigation of the degree of protein binding of a drug directly in its target tissue.
The interacting effects of storm surge intensification and sea-level rise on coastal resiliency: a high-resolution turbulence resolving case study
Authors: Cheikh Mohamad Ibrahim , Momen Mostafa
Published: October 2020

Climate change and global warming will increase the risk of coastal floods and storm surges, which can highly jeopardize communities and infrastructures along shorelines. There are two main drivers for this increase: surge amplification, which is caused by the projected hurricane intensification, and global sea-level rise (SLR). Although both factors can simultaneously affect storm surges, current knowledge on their interacting effects on the resiliency of coastal infrastructure is limited. To address this knowledge gap, we investigate the impacts of multiple storm surge scenarios on vehicles and buildings by varying wave heights, periods, and sea levels under current mitigation strategies. These surges are highly turbulent due to their high speed and wave-wave/bathymetry interactions. Large-scale numerical simulations with low-resolution (∼1–5 km) and depth-integrated models that do not resolve turbulence cannot assess the thorough impacts of these storm surges on infrastructures accurately. Hence, we employ a high-resolution numerical approach that is capable of resolving turbulent eddies down to ∼3 cm and capturing fluid-structure interactions. The distribution of hydrodynamic loads is found to vary nonlinearly in all directions with surge amplification and can significantly exceed calculations from classical theories that neglect turbulence. Two approaches from previous experiments are employed in a novel way to evaluate the resiliency of vehicles and infrastructure during storm surges. Our results indicate that vehicle mobility on the considered road will be imperiled by moderate surges (4 m wave height), and the elevated building will fail by surge intensification (8 m waves). We found that some storm-surge wave heights that are relatively safe now (e.g., 2 m waves for vehicles and 6 m for the building) will become hazardous in the future with an SLR. Therefore, road and building safety regulations should account for the interacting effects of hurricane intensification and SLR when devising mitigation strategies.
In operando x-ray photoelectron spectroscopy studies of H2 oxidation and H2O electrolysis on gadolinia-doped ceria electrodes
Authors: Wang Lei , Yu Yi , Gaskell Karen J , Crumlin Ethan J , Liu Zhi , Eichhorn Bryan W , Jackson Gregory S
Published: October 2020

In operando, ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) has been used to evaluate surface states of gadolinia-doped ceria (GDC) thin-film electrodes during H2 oxidation and H2O electrolysis, on yttria-stabilized zirconia (YSZ)-supported solid oxide electrochemical cells (SOCs). Porous nickel (Ni) and gold (Au) overlayers deposited on separate GDC thin films served as current collectors and potential electrocatalysts to facilitate heterogeneous chemistry for H2 oxidation or H2O electrolysis. Electrochemical characterization of the GDC thin-film electrodes complemented in operando XPS measurements of the O 1s spectra to correlate electrochemical overpotentials with surface chemistry near the Ni/GDC and Au/GDC interfaces. Shifts in O 1s binding energies across the metal/GDC/YSZ interfaces signified changes of local surface potential and provided a means of estimating kinetic parameters associated with charge transfer reactions. Effective oxygen partial pressure and surface potential impacted oxide vacancy and ceria polaron concentrations in the GDC, resulting in different reactivities of the GDC under the tested conditions. Both the Ni/GDC and Au/GDC demonstrated much higher currents for H2O electrolysis vs. H2 oxidation for comparable metal/GDC overpotentials due to increased electronic conductivity of the GDC under positive potentials and associated spreading of the electrochemically active region away from the triple-phase boundary. Higher electrochemical activity of the Ni/GDC electrode is attributed to the increased H2 activation on Ni in promoting charge transfer reactions (particularly for H2 oxidation). These results provide a basis for developing more informed reaction mechanisms for both H2 oxidation and H2O electrolysis of GDC-based composite electrodes in SOCs.
Electro-analytical comparison of commercial mono-crystalline silicon and PERC solar cells to maximize performance
Authors: Tripathi Brijesh , Mahapatra Apurba , Verma Deepak , Kalam Abul , Pandey Manoj Kumar , Trivedi Suverna , Kumar Manoj
Published: October 2020

In this article detailed electro-analytical comparison of the commercial mono-crystalline silicon and passivated emitter and rear contact (PERC) solar cells has been presented that can help in device optimization during manufacturing process. This study indicates fundamental differences between these two technologies in terms of the series resistance, shunt resistance and junction quality including ideality factor and doping concentration. Impedance spectroscopic analysis revealed a value of series resistance of 1 Ω for both the devices with no substantial difference, which suggest that employed metal contacts and base layer conductivity in both the solar cells have comparable electrical characteristics. The shunt resistance of 190 Ω cm2 and 98 Ω cm2 have been obtained for PERC and reference solar cells. The ideality factors of 1.9 and 2.2 have been obtained for PERC and reference solar cells, which indicate a better junction quality in PERC solar cells. From Mott-Schottky analysis a value of 0.65 V built-in potential has been obtained for both the solar cells. A doping density of 2.31 × 1016 cm−3 and 4.494 × 1016 cm−3 has been obtained for reference and PERC solar cells. This study intends to provide a basis for development of better optimization strategies to improve the performance of solar cells.
On the Ramanujan conjecture for automorphic forms over function fields I. Geometry
Authors: Sawin Will , Templier Nicolas
Published: October 2020

Let

G
G

be a split semisimple group over a function field. We prove the temperedness at unramified places of automorphic representations of

G
G

, subject to a local assumption at one place, stronger than supercuspidality, and assuming the existence of cyclic base change with good properties. Our method relies on the geometry of

Bun
G

\operatorname {Bun}_G

. It is independent of the work of Lafforgue on the global Langlands correspondence.
Stability and instability issues of the Weinstock inequality
Authors: Bucur Dorin , Nahon Mickaël
Published: October 2020

Given two planar, conformal, smooth open sets

Ω
\Omega

and

ω
\omega

, we prove the existence of a sequence of smooth sets

(

Ω
ϵ

)

(\Omega _\epsilon )

which geometrically converges to

Ω
\Omega

and such that the (perimeter normalized) Steklov eigenvalues of

(

Ω
ϵ

)

(\Omega _\epsilon )

converge to the ones of

ω
\omega

. As a consequence, we answer a question raised by Girouard and Polterovich on the stability of the Weinstock inequality and prove that the inequality is genuinely unstable. However, under some a priori knowledge of the geometry related to the oscillations of the boundaries, stability may occur.
A Shared Toxic History
Authors: Roller Heather F.
Published: October 2020

This essay is about the search for answers in family histories of illness, a search that may never end. It also explores how toxic exposure connects people—mothers and daughters, teachers and students—in unexpected ways. In the history classroom, the author finds new insights about environmental health in the shared experiences of course text authors, students, and families.
The paradoxical in vivo activity of β-lactams against metallo-β-lactamase-producing Enterobacterales is not restricted to carbapenems
Authors: Abdelraouf Kamilia , Reyes Sergio , Nicolau David P
Published: October 2020

Background

Using murine models of infection, we previously reported the potent in vivo activity of carbapenems against MBL-producing Enterobacterales despite the observed resistance in vitro. In the current study, we examined the in vivo activity of a cefepime human-simulated regimen against MBL-producing Enterobacterales in a murine thigh infection model.

Methods

A population of clinical isolates and isogenic engineered MBL-producing Enterobacterales transformants expressing MBLs but no detectable cefepime-hydrolysing serine β-lactamases were utilized. KPC-producing isolates were included as positive controls. Cefepime, piperacillin/tazobactam and meropenem MICs were determined using broth microdilution in conventional CAMHB and EDTA-supplemented (zinc-limited) broth. In vivo efficacy of a cefepime human-simulated regimen (2 g q8h as a 2 h infusion) was determined in the neutropenic murine thigh infection model against the test strains. Efficacy was measured as the change in log10 cfu/thigh at 24 h compared with 0 h controls.

Results

MBL-producing Enterobacterales strains were found to be cefepime, piperacillin/tazobactam and meropenem non-susceptible in conventional broth. Supplementation with EDTA at a concentration of 300 mg/L resulted in multi-fold reduction in the MICs and restoration of susceptibility. In accordance with the MICs generated in zinc-limited broth, administration of a cefepime human-simulated regimen was associated with substantial bacterial reductions among mice infected with MBL-producing Enterobacterales. Absence of MIC reduction in zinc-limited broth and lack of efficacy among mice infected with KPC-producing isolates were observed.

Conclusions

For MBL-producing Enterobacterales, susceptibility testing with Mueller–Hinton broth, a zinc-rich testing medium, is flawed since it does not recapitulate the host environment, in which zinc concentrations are low.
RNF219 interacts with CCR4–NOT in regulating stem cell differentiation
Authors: Du Hao , Chen Chen , Wang Yan , Yang Yang , Che Zhuanzhuan , Liu Xiaoxu , Meng Siyan , Guo Chenghao , Xu Manman , Fang Haitong , Wang Fengchao , Lin Chengqi , Luo Zhuojuan
Published: October 2020

Regulation of RNA stability plays a crucial role in gene expression control. Deadenylation is the initial rate-limiting step for the majority of RNA decay events. Here, we show that RING finger protein 219 (RNF219) interacts with the CCR4–NOT deadenylase complex. RNF219–CCR4–NOT exhibits deadenylation activity in vitro. RNA-seq analyses identify some of the 2-cell-specific genes and the neuronal genes significantly downregulated upon RNF219 knockdown, while upregulated after depletion of the CCR4–NOT subunit CNOT10 in mouse embryonic stem (ES) cells. RNF219 depletion leads to impaired neuronal lineage commitment during ES cell differentiation. Our study suggests that RNF219 is a novel interacting partner of CCR4–NOT and required for maintenance of ES cell pluripotency.
Measuring the fine structure constant on a white dwarf surface; a detailed analysis of Fe V absorption in G191-B2B
Authors: Hu J , Webb J K , Ayres T R , Bainbridge M B , Barrow J D , Barstow M A , Berengut J C , Carswell R F , Dumont V , Dzuba V , Flambaum V V , Lee C C , Reindl N , Preval S P , Tchang-Brillet W-Ü L
Published: October 2020

The gravitational potential φ = GM/Rc2 at the surface of the white dwarf G191-B2B is 10,000 times stronger than that at the Earth’s surface. Numerous photospheric absorption features are detected, making this a suitable environment to test theories in which the fundamental constants depend on gravity. We have measured the fine structure constant, α, at the white dwarf surface, used a newly calibrated Hubble Space Telescope STIS spectrum of G191-B2B, two new independent sets of laboratory Fe V wavelengths, and new atomic calculations of the sensitivity parameters that quantify Fe V wavelength dependency on α. The two results obtained are: Δα/α0 = (6.36 ± 0.35stat ± 1.84sys) × 10−5 and Δα/α0 = (4.21 ± 0.48stat ± 2.25sys) × 10−5. The measurements hint that the fine structure constant increases slightly in the presence of strong gravitational fields. A comprehensive search for systematic errors is summarised, including possible effects from line misidentifications, line blending, stratification of the white dwarf atmosphere, the quadratic Zeeman effect and electric field effects, photospheric velocity flows, long-range wavelength distortions in the HST spectrum, and variations in the relative Fe isotopic abundances. None fully account for the observed deviation but the systematic uncertainties are heavily dominated by laboratory wavelength measurement precision.
Searching for the radio remnants of short-duration gamma-ray bursts
Authors: Ricci R , Troja E , Bruni G , Matsumoto T , Piro L , O’Connor B , Piran T , Navaieelavasani N , Corsi A , Giacomazzo B , Wieringa M H
Published: October 2020

Neutron star mergers produce a substantial amount of fast-moving ejecta, expanding outwardly for years after the merger. The interaction of these ejecta with the surrounding medium may produce a weak isotropic radio remnant, detectable in relatively nearby events. We use late-time radio observations of short duration gamma-ray bursts (sGRBs) to constrain this model. Two samples of events were studied: four sGRBs that are possibly in the local (<200 Mpc) Universe were selected to constrain the remnant non-thermal emission from the sub-relativistic ejecta, whereas 17 sGRBs at cosmological distances were used to constrain the presence of a proto-magnetar central engine, possibly re-energizing the merger ejecta. We consider the case of GRB 170817A/GW170817 and find that in this case the early radio emission may be quenched by the jet blast-wave. In all cases, for ejecta mass range of ${M}_{\rm {ej}}\lesssim 10^{-2}\, (5\times 10^{-2})\, \mathrm{M}_\odot$, we can rule out very energetic merger ejecta ${E}_{\rm {ej}}\gtrsim 5\times 10^{52}\, (10^{53})\, \rm erg$, thus excluding the presence of a powerful magnetar as a merger remnant.
The most common habitable planets – II. Salty oceans in low-mass habitable planets and global climate evolution
Authors: Pinotti R , Porto de Mello G F
Published: October 2020

Global climate evolution models for habitable Earth-like planets do not consider the effect of ocean salinity on land ice formation through the hydrological cycle. We consider two categories of such planets: planets with deep oceans, but intrinsically high salinities due to the weaker salt removal process by hydrothermal vents; and planets with shallow oceans, where the increase in salt content and decrease in ocean area during the onset of glaciation cause a negative feedback, helping delay the spread of land ice. We developed a toy climate model of a habitable planet on the verge of an ice age, using a range of initial salt concentrations. Planets with deep oceans and high salinity show considerable increase in the time necessary to fill arctic land with ice sheets, up to 23 per cent considering the maximum salinity range. For planets with shallow oceans, the effect of intrinsic high salinity is reinforced by the negative feedback, counteracting positive feedbacks like the ice–albedo and Croll–Milankovitch perturbations, to the point of effectively terminating land ice sheet growth rate during the simulated time-scale. We also apply this model to the putative ocean of early Mars, finding intermediate results: salinity probably did not play a role in the evolution of Mars´ climate, considering the time-scale of its ice ages. We conclude that this phenomenon is essentially an abiotic self-regulation mechanism against ice ages and should be regarded in the context of habitable planets smaller and drier than the Earth, which may well represent the bulk of habitable planets.