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Background and Aims: Suitable N source supply is critical to improve plant growth and N uptake, but the importance of nitrate (NO3−) for rice (Oryza sativa L.) and microbiota is often neglected in acidic paddy soils where ammonium (NH4+) is dominant. This study aimed to explore the differential effects of NH4+ and NO3− on rice growth, fertilizer nitrogen recovery efficiency (FNRE), and rhizosphere bacterial community in acid soil. Methods: Two rice varieties, Kasalath (Al-sensitive indica) and Koshihikari (Al-tolerant japonica), were exposed to different N sources with or without lime in an acid soil. Results: Liming and NO3− application solely improved the growth and FNRE of the Al-sensitive rice, namely, by increasing soil pH and alleviating Al toxicity. Compared with liming and rice variety, N source had a more pronounced influence on rhizobacterial community composition. Of the two sources, NO3− had a stronger effect on the rhizobacterial community than NH4+. Remarkably, rice plants fed with NH4+ specifically recruited Desulfosporosinus and Desulfitobacterium associated with ferric NH4+ oxidation in the rhizosphere, whereas those exposed to NO3− recruited Alicyclobacillus with NO3−-reducing iron oxidation ability. Three keystone taxa were identified in a rhizobacterial co-occurrence network analysis: Alicyclobacillus, which was positively associated with rice growth and FNRE, and Acidobacteriales and WPS-2, both with negative associations. Conclusion: Compared with NH4+, NO3− enhances the growth and FNRE of Al-sensitive rice and exerts dominant effects on the rhizobacterial community, which indicates the importance of NO3− for rice and has instructive implications for N management in acid soil. [ABSTRACT FROM AUTHOR]

We study Choquard type equation of the form where N ≥ 3 , I α is the Riesz potential with α ∈ (0 , N) , p > 1 , q > 2 and ε ≥ 0 . Equations of this type describe collective behaviour of self-interacting many-body systems. The nonlocal nonlinear term represents long-range attraction while the local nonlinear term represents short-range repulsion. In the first part of the paper for a nearly optimal range of parameters we prove the existence and study regularity and qualitative properties of positive groundstates of (P 0) and of (P ε) with ε > 0 . We also study the existence of a compactly supported groundstate for an integral Thomas–Fermi type equation associated to (P ε) . In the second part of the paper, for ε → 0 we identify six different asymptotic regimes and provide a characterisation of the limit profiles of the groundstates of (P ε) in each of the regimes. We also outline three different asymptotic regimes in the case ε → ∞ . In one of the asymptotic regimes positive groundstates of (P ε) converge to a compactly supported Thomas–Fermi limit profile. This is a new and purely nonlocal phenomenon that can not be observed in the local prototype case of (P ε) with α = 0 . In particular, this provides a justification for the Thomas–Fermi approximation in astrophysical models of self-gravitating Bose–Einstein condensate. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the puncture accuracy and feasibility of contrast-enhanced ultrasound (CEUS) guided percutaneous nephrolithotomy (PCNL) in flank position for patients with no apparent hydronephrosis. Methods: Between May 2018 and June 2020, 72 kidney stone patients with no or mild hydronephrosis were randomized into two groups: a CEUS-guided PCNL group and a conventional ultrasound (US)-guided group. Patients' demographics and perioperative outcomes were compared, including the success rate of puncture via calyceal fornix, the success rate of a single-needle puncture, puncture time, operative time, postoperative hemoglobin loss, stone-free rate, incidence of complications and postoperative stay. Results: The success rate of puncture via calyceal fornix for CEUS-guided group was significantly higher than that for conventional US-guided group (86.1 vs. 47.2%, p = 0.002). Patients performed with CEUS-guided PCNL required shorter renal puncture time than those guided with conventional US (36.5 s vs. 61.0 s, p < 0.001). The median postoperative hemoglobin loss in the CEUS-guided group was significantly lower than that in conventional US-guided group (2.5 vs. 14.5 g/L, p < 0.01). There was no statistically significant difference in the success rate of a single-needle puncture, operative time, stone-free rate, incidence of complications and postoperative stay between the two groups. Conclusion: CEUS guidance facilitates identification of the renal calyx fornix, and benefits more precise renal puncture and less hemoglobin loss in PCNL. CEUS-guided PCNL in flank position is a feasible approach to the treatment of kidney stone patients with no apparent hydronephrosis. Trial registration number: ChiCTR1800015417. [ABSTRACT FROM AUTHOR]

We study the Schrödinger–Poisson–Slater equation where p ∈ (2 , 3) , λ > 0 , V (x) ∈ C (R 3 , R +) and I 2 (x) : = (4 π | x |) - 1 is the Newtonian potential. We prove the nonexistence of nontrivial solutions, existence of positive nonradial (and radial) ground-state solutions, and mountain-pass-type solutions to (SPS), depending on the values of parameters p and λ . To our knowledge, this is the first study of the existence of ground-state solutions at positive energy levels when p ∈ (2 , 3) . Furthermore, we show that a symmetry breaking occurs for the ground-state solutions, which is a purely nonlocal phenomenon that cannot be observed in the local prototype case. [ABSTRACT FROM AUTHOR]

Although the ultra-large induced strain of ferroelectric polymers has been achieved under an electric field near breakdown strength, the high driving voltage has been a long-standing obstacle for their safety applications in the actuator, transducer, wearable devices. To resolve this issue, novel core–shell structured CNT–Al2O3 nanoparticles grown via atomic layer deposition are utilized to improve the electromechanical properties of P(VDF-TrFE)-based nanocomposites under low applied fields. The electric coercive field (Ec) of nanocomposites substantially decreased with increase in fillers, giving rise to the boosted polarization and induced strain at low electric field. Accordingly, the nanocomposite with 1.1 wt% CNT–Al2O3 exhibited a 600% increase in transverse induced strain than that of the neat P(VDF-TrFE). For an identical induced strain, the required driving voltage of the nanocomposite could be effectively reduced by up to 200%. By numerically calculating electric field distribution and polarization, it was revealed that the higher ferroelectric property and lower driving voltage resulted from the enhanced interfacial polarization and the reduced field intensity to switch the polarization of the nanocomposites. This study provides a new route to improve the performance of ferroelectric polymers and holds great promise for using ferroelectric nanocomposites with low operating voltage in practical applications, including portable microfluidic and electronic devices. To reduce the driving voltage, a novel core–shell structured CNT–Al2O3 nanoparticle filler was utilized to improve the electromechanical properties of P(VDF-TrFE)-based nanocomposites under the low applied electric field. The introduction of CNT–Al2O3 filler in nanocomposite could significantly reduce the required electric field intensity for switching the polarization. Owning to its lowest Ec and higher polarization, the transverse induced strain of 1.1 wt% nanocomposite increased by 600% than that of the neat P(VDF-TrFE). [ABSTRACT FROM AUTHOR]

This research focuses on the evolution of mechanical behavior of bimodal mixtures undergoing compaction and diametrical compression. The clusters were built and discrete element method (DEM) was used to investigate the densification process and micromechanics of bimodal mixtures. Additionally, a more comprehensive investigate of the respective breakage of the bimodal mixtures has been carried out. On this basis, qualitative and quantitative analysis of the compressive force, force chain, contact bonds and density field evolution characteristics of the clusters are investigated during the compression process. The entire loading process of the clusters is divided into three stages: rearrangement, breakage and elastic–plastic deformation. Additionally, there are differences in the evolution of micromechanics behavior of different particles in the bimodal mixture, with pregelatinized starch breakage and deformation occurring before microcrystalline cellulose. With the tablet deformation, the fragmentation process of the tablet started at the point of contact and extended toward the center, and the curvature of the force chain increased. This approach may potentially hold a valuable new information relevant to important transformation forms batch manufacturing to advanced manufacturing for the oral solid dosage form. [ABSTRACT FROM AUTHOR]

The SE Tibetan Plateau, tectonically situated in the eastern India-Eurasia oblique convergence zone, has experienced multiple stages of deformation since the Cenozoic. Three major tectonic boundaries—the Ailaoshan-Red River, Chongshan-Lincang-Inthanon, and Gaoligong-Mogok shear zones—delineate the first-order tectonic framework in this region. The most striking structural features in the block interiors are a series of NW- and NE-trending fault systems, such as the Dayingjiang, Longlin-Ruili, Nantinghe, Red River, Weixi-Qiaohou, and Lancang-Genma faults, which have conjugate geometric relationships. In this study, we review these structures' geometric and kinematic characteristics and deformation histories. A synthesis of existing geological observations, geomorphological analysis, and chronological data reveal three major Cenozoic tectonothermal events, including crustal shortening, strike-slip shearing, and kinematic reversal. The boundary structures controlled the tectonic extrusion of plateau material during the early Oligocene-early Miocene. In the mid-late Miocene, NW- and NE-trending fault systems mostly experienced diachronous slip-sense inversions. The onset and spatial trend of regional kinematic reversal are constrained by existing chronologic data. Together with geophysical and geodetic observations, the activity and geodynamic drivers of the major fault systems and regional deformation styles are explored, revealing that the SE Tibetan Plateau underwent a transition from discrete (lateral block extrusion) to diffuse deformation in the mid-late Miocene. The intracontinental crustal deformation and its coupling with dynamic processes at depth during the plateau growth are discussed in the context of the India-Eurasia convergence. [ABSTRACT FROM AUTHOR]