bluuebunny/crossref_metadata_2025 huggingface dataset:
Perspectives about Environmental Tobacco Smoke Exposure from Mothers of Premature Infants
Authors: Colvin Bryanne N. , Parker Margaret G. , Hwang Sunah S. , Forbes Emma S. , Brown Kyria , Colson Eve R.
Published: August 2021

Objective The study aimed to better understand the perceptions of mothers of preterm infants regarding smoking behaviors and environmental tobacco smoke (ETS) exposure using qualitative methodology.

Study Design Using a Grounded Theory approach, we conducted in-depth, semi-structured interviews with mothers of preterm infants, both smokers and nonsmokers. Using the Theory of Planned Behavior (TPB) as a conceptual framework for our questions, we conducted and analyzed interviews until theoretical saturation was reached. Analysis included an iterative coding process resulting in theme development.

Results Our key themes aligned with the TPB domains of attitudes, perceived control, and social norms. Regarding attitudes, mothers expressed that smoking was bad for their infants and that preterm infants were more vulnerable than term infants. Regarding perceived control, mothers commented on their perceived ability to avoid ETS exposure with subthemes including strategies utilized to mitigate ETS exposure risk. Some mothers expressed difficulty avoiding ETS exposure, for example, when residing in high-density housing. Regarding perceived social norms, mothers whose family and friends were nonsmokers expressed ease avoiding ETS, while mothers whose family and friends were smokers expressed more difficulty avoiding ETS.

Conclusion Mothers used a variety of behaviors within the domains of the TPB to reduce ETS exposures in their preterm infants which can inform future neonatal intensive care unit-based interventional strategies.

Key Points
A Comparison of Costoclavicular Block and Interscalene Block for Pain Relief after Arthroscopic Shoulder Surgery
Authors: Pradhan Kamalakanta , Jayasingh Sarat Chandra , Nanda Sikata , Routray Sidharth Sraban
Published: August 2021

Introduction Interscalene block (ISB) is commonly used for efficient pain relief after arthroscopic shoulder surgery. But, it is linked with a greater occurrence of unilateral diaphragmatic paralysis (UDP). This may add to patient dissatisfaction and also may not be tolerated well by patients having respiratory diseases. We have compared the efficacy of costoclavicular block (CCB) with ISB for postoperative analgesia in patients undergoing arthroscopic shoulder surgery.

Materials and Methods Fifty patients were divided into two groups of 25 each (ISB or CCB group). In total, 20 mL of 0.5% levobupivacaine along with 4 mg of dexamethasone as adjuvant was used during both ultrasound-guided ISB and CCB. Numerical rating scale (NRS) scores for pain were assessed at 0, 0.5, 1, 2, 3, 6, 12, and 24 hours in postoperative period. The mean onset time of block, time of first painkiller demand, total painkiller demand for 24 hours postoperatively, patient wellbeing, incidence of UDP, and any other complications were recorded.

Results NRS pain scores in both groups at 0, 0.5, 1, 2, 3, 6, 12, and 24 hours were comparable. (p > 0.05) Mean onset time of block was earlier in ISB group contrary to CCB group (p < 0.05). There was higher occurrence of UDP in ISB group contrary to CCB group (p < 0.05). There was no notable variation regarding the time of first painkiller demand and total painkiller demand in the first 24 hours. Patients were more satisfied in CCB group contrary to ISB group.

Conclusion As CCB provided equivalent analgesia in postoperative period like ISB without any risk of UDP, it can be a better substitute to ISB for pain relief in arthroscopic shoulder surgery.
Discrete shallow water equations preserving symmetries and conservation laws
Authors: Dorodnitsyn V. A. , Kaptsov E. I.
Published: August 2021

The one-dimensional shallow water equations in Eulerian coordinates are considered. Relations between symmetries and conservation laws for the potential form of the equations and symmetries and conservation laws in Eulerian coordinates are shown. An invariant difference scheme for equations in Eulerian coordinates with arbitrary bottom topography is constructed. It possesses all the finite-difference analogs of the conservation laws. Some bottom topographies require moving meshes in Eulerian coordinates, which are stationary meshes in mass Lagrangian coordinates. The developed invariant conservative difference schemes are verified numerically using examples of flow with various bottom topographies.
Enhanced ion acceleration using the high-energy petawatt PETAL laser
Authors: Raffestin D. , Lecherbourg L. , Lantuéjoul I. , Vauzour B. , Masson-Laborde P. E. , Davoine X. , Blanchot N. , Dubois J. L. , Vaisseau X. , d’Humières E. , Gremillet L. , Duval A. , Reverdin Ch. , Rosse B. , Boutoux G. , Ducret J. E. , Rousseaux Ch. , Tikhonchuk V. , Batani D.
Published: August 2021

The high-energy petawatt PETAL laser system was commissioned at CEA’s Laser Mégajoule facility during the 2017–2018 period. This paper reports in detail on the first experimental results obtained at PETAL on energetic particle and photon generation from solid foil targets, with special emphasis on proton acceleration. Despite a moderately relativistic (<1019 W/cm2) laser intensity, proton energies as high as 51 MeV have been measured significantly above those expected from preliminary numerical simulations using idealized interaction conditions. Multidimensional hydrodynamic and kinetic simulations, taking into account the actual laser parameters, show the importance of the energetic electron production in the extended low-density preplasma created by the laser pedestal. This hot-electron generation occurs through two main pathways: (i) stimulated backscattering of the incoming laser light, triggering stochastic electron heating in the resulting counterpropagating laser beams; (ii) laser filamentation, leading to local intensifications of the laser field and plasma channeling, both of which tend to boost the electron acceleration. Moreover, owing to the large (∼100 μm) waist and picosecond duration of the PETAL beam, the hot electrons can sustain a high electrostatic field at the target rear side for an extended period, thus enabling efficient target normal sheath acceleration of the rear-side protons. The particle distributions predicted by our numerical simulations are consistent with the measurements.
Does mesoscopic elasticity control viscous slowing down in glassforming liquids?
Authors: Kapteijns Geert , Richard David , Bouchbinder Eran , Schrøder Thomas B. , Dyre Jeppe C. , Lerner Edan
Published: August 2021

The dramatic slowing down of relaxation dynamics of liquids approaching the glass transition remains a highly debated problem, where the crux of the puzzle resides in the elusive increase in the activation barrier ΔE(T) with decreasing temperature T. A class of theoretical frameworks—known as elastic models—attribute this temperature dependence to the variations of the liquid’s macroscopic elasticity, quantified by the high-frequency shear modulus G∞(T). While elastic models find some support in a number of experimental studies, these models do not take into account the spatial structures, length scales, and heterogeneity associated with structural relaxation in supercooled liquids. Here, we propose and test the possibility that viscous slowing down is controlled by a mesoscopic elastic stiffness κ(T), defined as the characteristic stiffness of response fields to local dipole forces in the liquid’s underlying inherent structures. First, we show that κ(T)—which is intimately related to the energy and length scales characterizing quasilocalized, nonphononic excitations in glasses—increases more strongly with decreasing T than the macroscopic inherent structure shear modulus G(T) [the glass counterpart of liquids’ G∞(T)] in several computer liquids. Second, we show that the simple relation ΔE(T) ∝ κ(T) holds remarkably well for some computer liquids, suggesting a direct connection between the liquid’s underlying mesoscopic elasticity and enthalpic energy barriers. On the other hand, we show that for other computer liquids, the above relation fails. Finally, we provide strong evidence that what distinguishes computer liquids in which the ΔE(T) ∝ κ(T) relation holds from those in which it does not is that the latter feature highly fragmented/granular potential energy landscapes, where many sub-basins separated by low activation barriers exist. Under such conditions, it appears that the sub-basins do not properly represent the landscape properties relevant for structural relaxation.
Effects of a velocity shear on double current sheet systems: Explosive reconnection and particle acceleration
Authors: Paul Arghyadeep , Vaidya Bhargav
Published: August 2021

The effect of a parallel velocity shear on the explosive phase of a double current sheet system is investigated within the 2D resistive magnetohydrodynamic framework. We further explore the effect of this shear on acceleration of test particles. The general evolution pattern of the double current sheets is similar for all sub-Alfvénic shears with respect to the initial transient phase, the onset of the plasmoid instability, and the final relaxation phase. We find that the theoretical scaling of the reconnection rate with shear holds if the rate is measured when the islands have a similar size. The larger island widths for lower shears greatly enhance the reconnection rate during the explosive phase. We have further examined the modification of the energy spectrum of the accelerated particles in the presence of a shear. Our results also show that the flow only modifies the high energy tail of the particle spectrum and has negligible effect on the power-law index. Individual particle trajectories help to explore the various mechanisms associated with the acceleration. Based on the location of the particles, the acceleration mechanisms are found to vary. We highlight the importance of the convective electric field in the inflow as well as the outflow region inside large magnetic islands in the acceleration of particles. The interaction and reflection of the particles with the reconnection exhausts inside the large scale primary magnetic islands is found to have a significant effect on the energization of the particles.
Charge-independent protein adsorption characteristics of epitaxial graphene field-effect transistor on SiC substrate
Authors: Nakai Hiroki , Akiyama Daiu , Taniguchi Yoshiaki , Kishinobu Iori , Wariishi Hiromichi , Ohno Yasuhide , Nagase Masao , Ikeda Takuya , Tabata Atsushi , Nagamune Hideaki
Published: August 2021

Charge-independent biomolecule detection using field-effect transistors (FETs) with single-crystal and large-area epitaxial graphene films fabricated on SiC substrates is demonstrated. To obtain clean graphene channel surfaces, FETs were fabricated using stencil mask lithography, which is a resist-free fabrication process. Proteins with various isoelectric points (pI: 5.6–9.9) were used as targets. Transfer characteristics [drain current (ID) vs solution-gate voltage (VG) characteristics] were measured by changing the pH of the buffer solution. The ID–VG characteristics exhibited a clear negative gate voltage shift for both positively and negatively charged proteins, indicating that the epitaxial graphene FETs could not detect the charge type of the protein and electrons were doped by the adsorption of both positively and negatively charged proteins. These results cannot be explained by conventional electrostatic effects. Therefore, it can be concluded that the detection of biomolecules by the epitaxial graphene FETs occurred through charge transfer from the proteins. Moreover, the dissociation constants between the proteins and epitaxial graphene films were as small as 100 pM, indicating the high sensitivity of the graphene FETs.
A conservative scaling analysis of Z-pinch dynamic Hohlraums for inertial confinement fusion
Authors: Xiao Delong , Mao Chongyang , Wen Wu , Wang Xiaoguang , Wang Guanqiong , Sun Shunkai , Zhao Yingkui , Ding Ning , Shu Xiaojian
Published: August 2021

In this paper, physical issues of Z-pinch dynamic Hohlraums aimed at ignition are numerically investigated. Three-wave propagation, including the thermal wave, the ablation shock driven by radiation emitted by the nested tungsten wire-array plasma, and the main shock, is found to determine the Hohlraum formation at high currents. Based on requirements of high temperature radiation, three-wave isolation, and a suitable Hohlraum-capsule size ratio, a converter with an initial radius of 5 mm is suggested. As the rise time of the drive current is varied, two kinds of Hohlraum designs are examined. One is to fix the wire-array mass and vary the wire-array radius; the other is to fix the wire-array radius and vary the wire-array mass. In situations of long rise times, the first kind of Hohlraum design should be adopted. Preliminary simulations show that a radiation source with a peak temperature over 308 eV and large enough energy with longer pulse duration is critical for a volume capsule design. Based on the considerations of (1) not underestimating the magneto-Rayleigh–Taylor effect, (2) avoiding the direct shock thermalization on the axis, (3) using of a suitable converter radius, and (4) iteration of dynamic Hohlraum and capsule calculations, a conservative Hohlraum design is proposed. In this Hohlraum design, a radiation pulse with a peak temperature of 312 eV and an efficient time duration of ∼9 ns, which is cut before the main shock arrives at the axis, is produced to drive a two-shell capsule to generate over 10 MJ fusion yield in the case of 50 MA and 100 ns.
Single source chemical vapor deposition (ssCVD) for highly luminescent inorganic halide perovskite films
Authors: Ishteev Arthur , Luchnikov Lev , Muratov Dmitry S. , Voronova Marina , Forde Aaron , Inerbaev Talgat , Vanyushin Vladislav , Saranin Danila , Yusupov Khabib , Kuznetsov Denis , Di Carlo Aldo
Published: August 2021

Recent studies of lead halide perovskites demonstrate outstanding optoelectronic properties for thin-film semiconductor device application. Perovskite photovoltaic and light-emitting diodes are on the way to the mass production and spread in commercial semiconductor devices. The lab-to-fab transition of perovskite devices requires adaptation of perovskite deposition methods to industrial semiconductor fabrication standards. In this work, we demonstrated the formation of highly luminescence perovskite films by single-source chemical vapor deposition (ssCVD). Several stoichiometry compositions were prepared from inorganic precursors of CsBr and PbBr2 by dry mechanochemical synthesis with following evaporation. The combination of mechanochemical synthesis and ssCVD is an attractive approach due to the ability to scale up to industrial level and the precise control over the evaporation rate with a single source. Among all compositions CsBr:PbBr2, we show that CsPb2Br5 maintains phase composition and photoluminescent properties for powder and film. This work provides a comparative study of evaporated film properties (PL, XRD, TEM) and modeling calculations of interphase optical transitions.
Stable valley-layer coupling and design principle in 2D lattice
Authors: Xu Xilong , He Zhonglin , Dai Ying , Huang Baibiao , Kou Liangzhi , Ma Yandong
Published: August 2021

Stable valley-layer coupling, which can be against spin–orbit coupling (SOC), is of both fundamental and technological importance as it offers a design principle for 2D valleytronics; however, a reliable mechanism to achieve the goal is missing. In this Letter, a general rule to design such valley-layer coupling is mapped out from symmetry analysis. The degenerate valleys with valley-contrasted layer physics and protected valley-layer coupling can be present in bilayer lattice, when special symmetry operations between layers depending on the inversion center are satisfied. Such valley-layer coupling and its stability against SOC are further revealed in a real material of MnF4 based on first-principles. The distinctive properties, such as optical selection of valley and electric polarization of interlayer excitons, are observed in such a unique system. Our results not only provide a feasible principle to design materials with stable valley-layer coupling but also greatly enrich the physics and broaden the scientific impact of 2D valleytronics.
Piezoelectric unimorph microcantilevers for measuring direct and converse piezoelectric coefficients
Authors: Jikyo Genki , Onishi Kouta , Nishikado Takumi , Kanno Isaku , Kanda Kensuke
Published: August 2021

In this study, we propose a new piezoelectric measurement method using unimorph microcantilevers to evaluate precise values of direct and converse piezoelectric coefficients for piezoelectric microelectromechanical system applications. We fabricated unimorph microcantilevers comprising 3-μm-thick polycrystalline Pb(Zr,Ti)O3 (PZT) thin films on a 20-μm-thick silicon (Si) layer. The converse piezoelectric coefficient was measured as |e31,f| = 3.9–5.8 C/m2, which was in good agreement with the measurement results of PZT thin films without microfabrication. The direct piezoelectric properties of the PZT microcantilevers were measured at the resonance frequency of each microcantilever, and |e31,f| was ∼2 C/m2, which was consistent with previous reports on the piezoelectric properties of a PZT thin film on Si. Since the measurement results included the effects of the stress condition and microfabrication damage, the measurement method of this study can evaluate the actual piezoelectric coefficient of piezoelectric properties in microdevice structures.
Theory of molecular emission power spectra. II. Angle, frequency, and distance dependence of electromagnetic environment factor of a molecular emitter in plasmonic environments
Authors: Lee Ming-Wei , Chuang Yi-Ting , Hsu Liang-Yan
Published: August 2021

Our previous study [S. Wang et al., J. Chem. Phys. 153, 184102 (2020)] has shown that in a complex dielectric environment, molecular emission power spectra can be expressed as the product of the lineshape function and the electromagnetic environment factor (EEF). In this work, we focus on EEFs in a vacuum–NaCl–silver system and investigate molecular emission power spectra in the strong exciton–polariton coupling regime. A numerical method based on computational electrodynamics is presented to calculate the EEFs of single-molecule emitters in a dispersive and lossy dielectric environment with arbitrary shapes. The EEFs in the far-field region depend on the detector position, emission frequency, and molecular orientation. We quantitatively analyze the asymptotic behavior of the EFFs in the far-field region and qualitatively provide a physical picture. The concept of EEF should be transferable to other types of spectra in a complex dielectric environment. Finally, our study indicates that molecular emission power spectra cannot be simply interpreted by the lineshape function (quantum dynamics of a molecular emitter), and the effect of the EEFs (photon propagation in a dielectric environment) has to be carefully considered.
Power electronics figure-of-merit of ScAlN
Authors: Fu Hanlin , Goodrich Justin C. , Ogidi-Ekoko Onoriode , Tansu Nelson
Published: August 2021

A power figure-of-merit (FOM) of ∼62.6–87.3 GW/cm2 is predicted for ScAlN, which represents a value 5–7 times larger than that of GaN. The parameters for the lattice-matched Sc0.18Al0.82N FOM calculation are investigated by first-principles density functional theory (DFT) calculations with the local density approximation. An energy gap of 5.65 eV and an electron effective mass of 0.46m0 are obtained from the DFT band structure calculation of Sc0.1875Al0.8125N. The electron mobility of Sc0.18Al0.82N is simulated based on Boltzmann transport equations, which consider scatterings by ionized impurities, dislocations, alloy scattering, acoustic phonons, and optical phonons. The remarkable power FOM shows that lattice-matched Sc0.18Al0.82N possesses a large breakdown voltage and low specific on-resistance, which suggests the great potential for Sc0.18Al0.82N to be implemented in high-voltage power electronics for improved device performance.
Focus of ultrasonic underwater sound with 3D printed phononic crystal
Authors: Li Zhaoxi , Yang Shenghui , Wang Danfeng , Shan Han , Chen Dongdong , Fei Chunlong , Xiao Meng , Yang Yintang
Published: August 2021

Ultrasound is widely used in various applications, ranging from ultrasound imaging to particle manipulation. Acoustic materials, such as phononic crystal (PC) and metamaterials, are designed to control the propagation and concentration of ultrasound. While traditional metal-based underwater PCs are usually limited to large 2D structures and used for low-frequency sound wave manipulation, it is difficult to reach the ultrasonic frequency region of the order of 1 MHz with cumbersome metallic structures. Here, in this work, we proposed a 3D printed gradient-index phononic crystal (GRIN PC) lens based on the hyperbolic secant index profile. With a huge impedance difference between air and the 3D printing materials, the GRIN PC lens adhered to the ultrasonic transducers can easily manipulate the propagation of acoustic waves and achieve wave focusing. This transparent and flat lens demonstrates the beam focusing in water even at a high frequency. The integration and miniaturization of transducer and lens make particle capture convenient in relevant medical applications.
Tuning magnetic and optical properties through strain in epitaxial LaCrO3 thin films
Authors: Sharma Yogesh , Paudel Binod , Lee Jegon , Choi Woo Seok , Yang Zhenzhong , Wang Han , Du Yingge , Kang Kyeong Tae , Pilania Ghanshyam , Chen Aiping
Published: August 2021

We report on the effect of epitaxial strain on magnetic and optical properties of perovskite LaCrO3 (LCO) single crystal thin films. Epitaxial LCO thin films are grown by pulsed laser deposition on proper choice of substrates to impose different strain states. A combined experimental and theoretical approach is used to demonstrate the direct correlation between lattice-strain and functional properties. The magnetization results show that the lattice anisotropy plays a critical role in controlling the magnetic behavior of LCO films. The strain induced tetragonality in the film lattice strongly affects the optical transitions and charge transfer gap in LCO. This study opens possibilities to tailor the functional properties of LCO and related materials by strain engineering in epitaxial growth.
Illuminating the complex role of the added mass during vortex induced vibration
Authors: Wang Zhicheng , Fan Dixia , Triantafyllou Michael S.
Published: August 2021

The role of the added mass coefficient in vortex induced vibration (VIV) of the bluff body is complex and elusive. It is certain that decoding the relationship between the added mass and the vibration pattern will benefit the prediction and prevention of VIV. We present a study on VIV of a long flexible cylinder and forced vibration of a rigid cylinder, in a combination of experimental optical measurements and high-fidelity numerical simulation. We focus on uniform flow over a uniform cylinder at a fixed Reynolds number, Red = 900, but systematically varied the motion amplitude in the in-line (Axd) and cross-flow direction (Ayd), as well as the phase angle (θ) between the motions. We show that θ∈[π2,3π2] is associated with negative added mass coefficients in the cross-flow direction (Cmy < 0), and there is a strong correlation between the vortex shedding mode of “2P” or “P+S” and Cmy < 0.
Ballistic heat conduction in semiconductor nanowires
Authors: Anufriev Roman , Wu Yunhui , Nomura Masahiro
Published: August 2021

Ballistic thermal transport is a remarkable nanoscale phenomenon with possible applications in microelectronics. In the past decade, research on ballistic thermal transport focused on the measurements of length-dependent thermal conductivity in semiconductor nanowires. In this Perspective article, we review the experimental demonstrations of this phenomenon in nanowires of various materials and sizes and at different temperatures. Our literature analysis reveals a controversy between works reporting two distinct pictures of ballistic conduction: perfectly ballistic conduction even at room temperature and weak quasi-ballistic conduction mainly below room temperature. Simulations seem to support the weaker version of the effect. Thus, future experiments are expected to resolve this controversy.
Spatial and temporal dynamics of a supersonic mixing layer with a blunt base
Authors: Li Lantian , Li Hao
Published: August 2021

A supersonic mixing layer with a blunt base is of practical significance to engineering. Two flow configurations with splitter thicknesses of 1 mm (TN) and 5 mm (TK) are simulated using large eddy simulation. The cluster-based network model (CNM) projects the supersonic mixing layer into a ten-centroid based low-dimensional dynamical system. The CNM’s outputs of TN and TK cases are compared in order to better understand the spatial and temporal physics. The given baseline case (TN) demonstrates a quasi-steady dynamics with a periodic visit between ten centroids. Each cluster occupies a nearly uniform space region and is also populated with equal probability. The CNM identifies ten centroids associated with these two flow regimes observed in the TK case: Kelvin–Helmholtz vortex and vortex pairing. According to the resolved centroids, increasing the thickness of the splitter plate complicates the flow structures and expands the high-dimensional state space. The CNM presents probable state transitions, revealing that the temporal dynamics in the whole field exhibits highly intermittent behaviors, with large shape modifications but small fluctuations in turbulent kinetic energy. In the near-wake field, the reattachment point and shock wave behave similarly that they move downstream and upstream alternatively. The blunt base supersonic mixing layer, in aggregate, increases the turbulent kinetic energy by 20.5%.
Dexamethasone may inhibit placental growth by blocking glucocorticoid receptors via phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin and reactive oxygen species/AMP-activated protein kinase signalling pathways in human placental JEG-3 cells
Authors: Zhan Xin , Xie Yiran , Sun Liping , Si Qi , Shang Hongkai
Published: August 2021

This study explored the molecular mechanism underlying the effects of dexamethasone (DEX, 1 µM) on glucose transporters (GLUT) in JEG-3 human placental choriocarcinoma cells. JEG-3 cells were treated with DEX, an expression plasmid encoding human glucocorticoid receptor α (GRα), pcDNA3.1-GRα, GRα short interference (si) RNA, LY294002, xanthine oxidase (XO)/hypoxanthine (HX), rapamycin, insulin-like growth factor (IGF) 1, N-acetylcysteine (NAC) or phosphatidic acid (PA), and cell proliferation, apoptosis, mitochondrial membrane potential (MMP), human chorionic gonadotrophin (hCG) content, human placental lactogen (hPL) content, glucose uptake, reactive oxygen species levels and signalling pathway modulation were evaluated. Treatment of JEG-3 cells with DEX (1 µM), GRα siRNA, LY294002 (50 µM), XO/HX (7.2 µM/36 nM) or rapamycin (80 nM) inhibited cell proliferation, induced apoptosis, significantly decreased MMP and hCG and hPL content and increased ROS levels. In addition, glucose uptake was decreased through downregulation of the mRNA and protein expression of GRα, GLUT1 and GLUT3. Treatment of JEG-3 cells with GRα siRNA, LY294002, XO/HX or rapamycin inhibited phosphorylation of phosphatidylinositol 3-kinase (PI3K), Akt, glycogen synthase kinase 3 and mammalian target of rapamycin (mTOR) and induced the phosphorylation of AMP-activated protein kinase (AMPK) and tuberous sclerosis complex 2. The effects of GRα overexpression and IGF1 (100 nM), NAC (5 nM) or PA (100 µM) treatment on JEG-3 cells contrasted with those of DEX treatment. DEX blocked glucose uptake by downregulating GRα expression, which reduced GLUT1 and GLUT3 mRNA and protein expression, which, in turn, may have inhibited the PI3K/AKT/mTOR pathway and activated the ROS/AMPK pathway.
Evolution and seed dormancy shape plant genotypic structure through a successional cycle
Authors: Agrawal Anurag A. , Hastings Amy P. , Maron John L.
Published: August 2021

Significance

Studies that experimentally examine evolution have provided critical insight in biology. Indeed, rigorous and replicated laboratory experiments have revealed parallel evolution and have proved essential to understanding evolutionary processes. Nonetheless, a typical limitation of such work is the lack of ecological realism. We report on a decade-long field experiment with a native plant (common evening primrose) that advances our understanding of how populations adapt to environmental change. In particular, we address whether the common strategy of seed dormancy significantly alters the evolutionary trajectory of populations. We find that population genetic diversity is restored following a period of sustained dormancy. Nonetheless, the impact of past natural selection persisted under some conditions.
The strength of the Earth’s magnetic field from Pre-Pottery to Pottery Neolithic, Jordan
Authors: Di Chiara Anita , Tauxe Lisa , Levy Thomas E. , Najjar Mohammad , Florindo Fabio , Ben-Yosef Erez
Published: August 2021

Significance

The Earth’s magnetic field has changed significantly in the past with implications for related phenomena, such as deep-Earth processes and evolution of life. Accurate datasets of its past behavior also provide a dating tool. We present data from Neolithic ceramics and flint from Jordan. Our results are among the oldest in the Levant, covering a period of major changes in human history. The data help in refining the resolution of the archaeomagnetic curve, in turn enhancing its use as a dating tool and for understanding past field behavior. Moreover, we demonstrate the potential for the use of flint material, the most common raw material for the manufacturing of tools in the entire Paleolithic and younger periods, for archaeointensity investigations.
Global range expansion history of pepper (Capsicumspp.) revealed by over 10,000 genebank accessions
Authors: Tripodi Pasquale , Rabanus-Wallace Mark Timothy , Barchi Lorenzo , Kale Sandip , Esposito Salvatore , Acquadro Alberto , Schafleitner Roland , van Zonneveld Maarten , Prohens Jaime , Diez Maria José , Börner Andreas , Salinier Jérémy , Caromel Bernard , Bovy Arnaud , Boyaci Filiz , Pasev Gancho , Brandt Ronny , Himmelbach Axel , Portis Ezio , Finkers Richard , Lanteri Sergio , Paran Ilan , Lefebvre Véronique , Giuliano Giovanni , Stein Nils
Published: August 2021

Significance

This study provides a deep population genomic analysis of 10,000Capsicumaccessions held in genebanks and representing a frame of the global diversity of the genus. By combining single nucleotide polymorphisms (SNPs) based data and passport information, we investigated the genomic diversity and population structure of wild and domesticated peppers, tracing back to routes of evolution and providing a model ofCapsicum annuumdistribution, which reflects human trade and historical/cultural influences. Our results highlight west–east routes of expansion, shedding light on the links between South and Mesoamerica, Africa, and East/South Asia, the latter two constituting important diversification centers of pepper diversity. Finally, we outline a roadmap for genebank management and future direction for better exploitation of germplasm resources.
Electrophysiological characterization of the hERG R56Q LQTS variant and targeted rescue by the activator RPR260243
Authors: Kemp Jacob M. , Whittaker Dominic G. , Venkateshappa Ravichandra , Pang ZhaoKai , Johal Raj , Sergeev Valentine , Tibbits Glen F. , Mirams Gary R. , Claydon Thomas W.
Published: August 2021

Human Ether-à-go-go (hERG) channels contribute to cardiac repolarization, and inherited variants or drug block are associated with long QT syndrome type 2 (LQTS2) and arrhythmia. Therefore, hERG activator compounds present a therapeutic opportunity for targeted treatment of LQTS. However, a limiting concern is over-activation of hERG resurgent current during the action potential and abbreviated repolarization. Activators that slow deactivation gating (type I), such as RPR260243, may enhance repolarizing hERG current during the refractory period, thus ameliorating arrhythmogenicity with reduced early repolarization risk. Here, we show that, at physiological temperature, RPR260243 enhances hERG channel repolarizing currents conducted in the refractory period in response to premature depolarizations. This occurs with little effect on the resurgent hERG current during the action potential. The effects of RPR260243 were particularly evident in LQTS2-associated R56Q mutant channels, whereby RPR260243 restored WT-like repolarizing drive in the early refractory period and diastolic interval, combating attenuated protective currents. In silico kinetic modeling of channel gating predicted little effect of the R56Q mutation on hERG current conducted during the action potential and a reduced repolarizing protection against afterdepolarizations in the refractory period and diastolic interval, particularly at higher pacing rates. These simulations predicted partial rescue from the arrhythmic effects of R56Q by RPR260243 without risk of early repolarization. Our findings demonstrate that the pathogenicity of some hERG variants may result from reduced repolarizing protection during the refractory period and diastolic interval with limited effect on action potential duration, and that the hERG channel activator RPR260243 may provide targeted antiarrhythmic potential in these cases.
Detecting Pb2+ by a ‘turn-on’ fluorescence sensor based on DNA functionalized magnetic nanocomposites
Authors: Li Jiayi , Jin Yu , Wang Yaoqiang , Zhao Yilin , Su Haijia
Published: August 2021

Sensitive and selective detection of the lead ion (Pb2+) plays an important role in terms of both human health and environmental protection, as the heavy metal is fairly ubiquitous and highly toxic. The highly stable fluorescence biosensor is composed of Fe3O4@TiO2 core–shell nanocomposites, functionalized with a carboxyl fluorescein labeled DNA. The morphology, physical and chemical properties of the sensing nanomaterials were studied by transmission electron microscopy, FT-IR spectroscopy (FT-IR), x-ray powder diffraction and vibrating sample magnetometer. UV–visible and fluorescence spectroscopy were used to characterize the fluorescein functionalized magnetic nanoparticles. The performance of Pb2+ detection displayed an excellent linearity (R
2 = 0.995) in the range of 10−10 to 5 × 10−9 ppm with a detection limit of 10−10 ppm, based on the optimization of the fabrication process and aptamers’ specification. The fluorescence biosensor has an accurate response, excellent recoveries and high adsorbent capacities. It was successfully applied for the determination of Pb2+ in contaminated water and serum samples; the detection of limit in both media were 10−10 ppm. These features ensure the potential use of aptamer functionalized magnetic nanocomposites as a new class of non-toxic biocompatible sensors for biological and environmental applications.
Effect of Thai Silk Fibroin on Mechanical Properties of Bioactive Glass Silk Fibroin Hybrid Bone Scaffolds
Authors: Vejpongsa Ayuth , Thongnuek Peerapat
Published: August 2021

Bioactive glass (70 mol% Si and 30% Ca; 70S30C) has been used as tissue engineering scaffolds in various research despite its brittleness due to its easy-to-replicate formula, extensive interconnected pores and natural bone bonding property of bioactive glass (BG). Thai silk fibroin (SF) is natural polymer with many desirable properties; biocompatibility, mechanical strength, biodegradability. Using BG-SF hybrid scaffolds could employ the positive effects of both bioactive glass and silk fibroin. Serving as bone scaffolds, BG-SF scaffolds must resist compression and other types of mechanical load depending on the application. This study fabricates scaffolds with various ratios of BG:SF (BG:SF; 90:10, 80:20 with 100:0 as control), and their stress-strain profiles were investigated. As expected, the scaffolds with highest BG content exhibited the curve resembling that of porous foam while the elastomeric stress-strain profile was becoming more evident when the SF content was increased. This study hence demonstrated fine-tuning mechanical properties of the BG using locally enriched SF.
Multi-criteria Flood Susceptibility Assessment Using Remote Sensing and GIS-based Approaches in Chi River Basin, Thailand
Authors: Sakmongkoljit K , Homtong N , Surakotra N , Silaratana N
Published: August 2021

The flood susceptibility map is a comprehensive resource for forecasting and preventing floods worldwide, particularly where floods occur on a regular basis, which is missing in numerous developing-country basins. The recurring flood hazard in Thailand is an endless problem as there is still a lack of understanding of the underlying causative factors. This research provides an answer of certain flood-causative parameters and the effects on flood susceptibility in Chi River Basin (CRB), Thailand, using an Analytical Hierarchical Process (AHP) method. As the result, total of seven hydrogeomorphological parameters can be ranked by its influence on flood hazard in the CRB, as follows, the distance from the river, elevation, geology, soil type, land use, drainage density, and geomorphology, respectively. Combination of all flood-causative parameters based on their weights and ranks provided the flood susceptibility map. The map was evaluated as accurate relative to previous satellite-based flood maps using a binary classification test, providing a robust flood susceptibility map. The findings of this work have contributed to a decent understanding of the present problem of floods in the CRB in the context of its actual causes, which is beneficial for a water management scheme.
Reduction Of Chloride In Raw Water By Nanofiltration And Reverse Osmosis
Authors: Panwattanakul Suppakit , Kasikun Kasipong , Musikavong Charongpun , Sinyoung Suthatip
Published: August 2021

This research is aimed at determining the reduction of chloride in the raw water of a water supply plant using nanofiltration and reverse osmosis. Raw water was prepared by adding NaCl at the concentrations of 300 and 600 mg/L. This work used a PACl at 15 mg/L as the pre-treatment for removing turbidity and DOC. Coagulated water was filtered with GF/C filter as the filtration process for minimizing membrane blockage. At chloride concentrations of 300 and 600 mg/L, the flux values were in the range of 66.7-70.0 and 62.8–65.0 L/m 2-h for NF-270 and 17.2–20.6 and 18.3-20.8 L/m 2-h for TW-30, respectively. The performance capabilities of NF-270 and TW-30 for reducing chloride were significantly different. NF-270 and TW-30 membranes were able to reduce chloride by 67 % and 92 % at the added dose of 300 mg/L, respectively. At the added amount of 600 mg/L, NF-270 and TW-30 membranes could reduce chloride by 63 % and 85 %, respectively. In the case of chloride in raw water at a concentration lower than 600 mg/L, the nanofiltration is suitable for removing chloride in regards to the low operation costs compared with the reverse osmosis. Nanofiltration could reduce chloride to lower concentration levels than the water supply standards of the Provincial Waterworks Authority.
Hydrothermal blackening on AISI 4140 steel with and without hydrazine hydrate
Authors: Wiman P , Doungkaew K , Siripongsakul T
Published: August 2021

The blackening coating is a conversion coating with the black colour of crystallised magnetite (Fe 3O4) on the surface of steel. The coating is to be soaked with oil or wax to prevent the corrosive environment. Recently, the technique to synthesise the black coating, hydrothermal method is introduced. In the synthesis process, hydrazine hydrate (N2H4·H2O) is often recommended as a catalyst but it is also reported toxicity. In this work, AISI 4140 was hydrothermally immersed in the FeSO4·7H2O added NaOH solution with and without addition of hydrazine hydrate. During the process, the temperature and pressure of the chamber were controlled at 140°C and 2 bar, respectively. To confirm the formation of Fe 3O4, the samples were characterised by SEM and XRD. These results showed that the coatings were composed of octahedron morphology in all conditions and the thicknesses of the coating with hydrazine hydrate concentration of 0.0, 0.1, and 0.5M were 7.05, 9.25, and 8.75 μm, respectively. With hydrazine hydrate, the Fe3O4 layer can be easily formed. However, the results of the oxalic acid spot test and potentiodynamic polarisation indicated the equivalence in quality of the coating, despite the absence of hydrazine hydrate.
Machine learning could combat epidemic spread
Authors: Harris Margaret
Published: August 2021

A neural network has been used to test ways to eliminate a disease while isolating only part of the population, as Margaret Harris reports
Muons and streetlights
Authors: Crease Robert P
Published: August 2021

Robert P Crease explains why the new measurement of “g–2” was just the latest in a series of such experiments that stretches back more than 60 years
Light at the end of the tunnel
Authors: Appell David
Published: August 2021

David Appell reviews Lightspeed: the Ghostly Aether and the Race to Measure the Speed of Light by John Spence
Learning from the impossible
Authors: Ball Philip
Published: August 2021

Philip Ball reviews The Science of Can and Can’t by Chiara Marletto
Native multiqubit Toffoli gates on ion trap quantum computers
Authors: Goel Nilesh , Freericks J K
Published: August 2021

We examine the detailed scenario for implementing n-control-qubit Toffoli gates and select gates on ion-trap quantum computers, especially those that shuttle ions into interaction zones. We determine expected performance of these gates with realistic parameters for an ion-trap quantum computer and taking into account the time variation of the exchange integrals. This allows us to estimate the errors due to spin–phonon entanglement as well. While there are challenges with implementing these gates, because their performance always has some degree of error, they should be feasible on current hardware, but they may be too slow to be used efficiently in quantum codes on noisy intermediate scale quantum computers. Here, we estimate these gate times for Yb-based ion trap quantum computers.
Effects of initial invasive vs. initial conservative treatment strategies on recurrent and total cardiovascular events in the ISCHEMIA trial
Authors: Lopez-Sendon Jose L , Cyr Derek D , Mark Daniel B , Bangalore Sripal , Huang Zhen , White Harvey D , Alexander Karen P , Li Jianghao , Nair Rajesh Goplan , Demkow Marcin , Peteiro Jesus , Wander Gurpreet S , Demchenko Elena A , Gamma Reto , Gadkari Milind , Poh Kian Keong , Nageh Thuraia , Stone Peter H , Keltai Matyas , Sidhu Mandeep , Newman Jonathan D , Boden William E , Reynolds Harmony R , Chaitman Bernard R , Hochman Judith S , Maron David J , O’Brien Sean M
Published: August 2021

Aims

The International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial prespecified an analysis to determine whether accounting for recurrent cardiovascular events in addition to first events modified understanding of the treatment effects.

Methods and results

Patients with stable coronary artery disease (CAD) and moderate or severe ischaemia on stress testing were randomized to either initial invasive (INV) or initial conservative (CON) management. The primary outcome was a composite of cardiovascular death, myocardial infarction (MI), and hospitalization for unstable angina, heart failure, or cardiac arrest. The Ghosh–Lin method was used to estimate mean cumulative incidence of total events with death as a competing risk. The 5179 ISCHEMIA patients experienced 670 index events (318 INV, 352 CON) and 203 recurrent events (102 INV, 101 CON). A single primary event was observed in 9.8% of INV and 10.8% of CON patients while ≥2 primary events were observed in 2.5% and 2.8%, respectively. Patients with recurrent events were older; had more frequent hypertension, diabetes, prior MI, or cerebrovascular disease; and had more multivessel CAD. The average number of primary endpoint events per 100 patients over 4 years was 18.2 in INV [95% confidence interval (CI) 15.8–20.9] and 19.7 in CON (95% CI 17.5–22.2), difference −1.5 (95% CI −5.0 to 2.0, P = 0.398). Comparable results were obtained when all-cause death was substituted for cardiovascular death and when stroke was added as an event.

Conclusions

In stable CAD patients with moderate or severe myocardial ischaemia enrolled in ISCHEMIA, an initial INV treatment strategy did not prevent either net recurrent events or net total events more effectively than an initial CON strategy.

Clinical trial registration

ISCHEMIA ClinicalTrials.gov number, NCT01471522, https://clinicaltrials.gov/ct2/show/NCT01471522.
Relationships between work, lifestyles, and obesity: cross-sectional study based on the 2017 Spanish National Health Survey
Authors: de Pedro-Jiménez Domingo , Romero-Saldaña Manuel , Molina-Recio Guillermo , de Diego-Cordero Rocío , Cantón-Habas Vanesa , Molina-Luque Rafael
Published: August 2021

Aims

Overweight and obesity are affected by factors such as dietary transgressions and lack of exercise, as well as less obvious factors such as shift work and sedentary working. (i) To explore the associations between overweight and obesity (O/O) with working conditions such as type of job position, and work shifts; (ii) to know the associations between O/O with lifestyles (physical activity, eating habits, and tobacco and alcohol consumption).

Methods and results

A cross-sectional, population-based design was used based on the Spanish National Health Survey. The final sample consisted of 9097 workers aged between 18 and 65. The influence of the explanatory variables on the outcome variable (body mass index) was examined using logistic regression. The prevalence of O/O increased by 4% for every additional year of age (P < 0.001) and was 3.1 times more frequent among men (P < 0.001). It also was 20% higher in night work or rotating shifts (P < 0.01), and 14.9% lower in sedentary job positions (P < 0.05). Low consumption of the following foods was significantly associated with a reduction in O/O: meat (16.2%), fish (75.4%), cured meats (35.1%), dairy products (33.3%), and snacks (47.1%).

Conclusion

Age, men, engaging in moderate or low levels of physical activity, being an ex-smoker, working during the night or rotating shifts, holding a non-sedentary job position, having a low to moderate consumption of pasta, potatoes, and rice, a moderate consumption of bread and cereals, as well as dairy products, vegetables, sugary foods, and fast food, have been significantly associated with a higher prevalence of O/O. No relationships were identified between the consumption of alcohol, fruit, eggs, pulses, and sugary soft drinks.