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The transfer of land plays a crucial role in revitalizing land resources, acting as a catalyst for promoting the high-quality development of agriculture. The land transfer ratio is a crucial metric for assessing the progress of rural land transfer and the effective allocation of rural land resources. Thus, this study examines the rural land transfer ratio across 30 provinces in China from 2005 to 2020. The study explores the distribution characteristics of the ratio using the rank-size rule and trend surface analysis. The LISA space-time transition method is employed to analyze the spatial and temporal dynamics of the rural land transfer ratio and examine its convergence. The study aims to comprehensively analyze the spatial distribution characteristics and evolutionary patterns of rural land transfer in China, illustrating the convergence and influencing factors during the development process. The results indicate that: (1) The rural land transfer ratio in China is generally increasing, with a spatial pattern showing an upward trend from west to east and from north to south. The main spatial contrast is between the eastern and western regions, with a relatively minor distinction between the southern and northern regions. (2) The LISA space-time transition highlights a significant spatial locking effect in China's rural land transfer ratio, suggesting strong spatial integration in its evolution. (3) Clear indications of σ convergence, absolute β convergence, and club convergence are evident in China's rural land transfer ratio. This suggests a gradual reduction in internal disparities among provinces and regions, where areas with higher land transfer ratios influence spatial spillover effects on adjacent lower areas. (4) Factors such as transportation infrastructure, irrigation, water conservancy construction, and farmers' per capita income collectively influence the spatial and temporal evolution of China's rural land transfer ratio, with dominant driving factors varying across different periods. [ABSTRACT FROM AUTHOR]

Fast and accurate counting and positioning of flowers is the foundation of automated flower cultivation production. However, it remains a challenge to complete the counting and positioning of high-density flowers against a complex background. Therefore, this paper proposes a lightweight flower counting and positioning model, Light-FC-YOLO, based on YOLOv8s. By integrating lightweight convolution, the model is more portable and deployable. At the same time, a new efficient detection head, Efficient head, and the integration of the LSKA large kernel attention mechanism are proposed to enhance the model's feature detail extraction capability and change the weight ratio of the shallow edge and key point information in the network. Finally, the SIoU loss function with target angle deviation calculation is introduced to improve the model's detection accuracy and target positioning ability. Experimental results show that Light-FC-YOLO, with a model size reduction of 27.2% and a parameter reduction of 39.0%, has a Mean Average Precision (mAP) and recall that are 0.8% and 1.4% higher than YOLOv8s, respectively. In the counting comparison experiment, the coefficient of determination (R2) and Root Mean Squared Error (RMSE) of Light-FC-YOLO reached 0.9577 and 8.69, respectively, both superior to lightweight models such as YOLOv8s. The lightweight flower detection method proposed in this paper can efficiently complete flower positioning and counting tasks, providing technical support and reference solutions for automated flower production management. [ABSTRACT FROM AUTHOR]

In this work, high-frequency forced vibrations of lateral field excitation (LFE) devices with stepped electrodes based on monoclinic crystals GdCOB are modeled, and the influence laws of the device parameters (the step number, size, and thickness of the stepped electrodes) on the energy-trapping effects of the device are revealed. The results show that the step number has a significant effect on the energy-trapping effect of the device: with the increase in the step number, the stronger energy-trapping effect of the device can be obtained; with the increase in the thickness difference of two layers of electrodes, the energy-trapping effect of the device becomes stronger; with the increase in the difference of the electrode radius, the energy-trapping effect of the device is enhanced gradually. The results of this work can provide an important theoretical basis for the design of stepped-electrode LFE resonators and sensors with high-quality factors based on monoclinic crystals. [ABSTRACT FROM AUTHOR]

The influence of Ti addition (~0.10 wt%) on hot ductility of as-cast high-manganese austenitic steels has been examined over the temperature range 650–1,250 °C under a constant strain rate of 10−3 s−1 using Gleeble3500 thermal simulation testing machine. The fracture surfaces and particles precipitated at different tensile temperatures were characterized by means of scanning electron microscope and X-ray energy dispersive spectrometry (SEM–EDS). Hot ductility as a function of reduction curves shows that adding 0.10 wt% Ti made the ductility worse in the almost entire range of testing temperatures. The phases’ equilibrium diagrams of precipitates in Ti-bearing high-Mn austenitic steel were calculated by the Thermo-Calc software. The calculation result shows that 0.1 wt% Ti addition would cause Ti(C,N) precipitated at 1,499 °C, which is higher than the liquidus temperature of high-Mn austenitic steel. It indicated that Ti(C,N) particles start forming in the liquid high-Mn austenitic steel. The SEM–EDS results show that Ti(C,N) and TiC particles could be found along the austenite grain boundaries or at triple junction, and they would accelerate the extension of the cracks along the grain boundaries.

Topological transports of elastic waves have attracted much attention because of their unique immunity to defects and backscattering-suppression ability. Periodic lattice structures are ideal carriers of elastic-wave transports due to their ability to manipulate elastic waves. Compared with honeycomb-lattice structures, the wave-guide-path designs of triangular-lattice structures have higher flexibility. In this paper, topological transports of elastic waves in the periodic triangular-lattice structure are explored. It is shown that differences between intra-coupling and inter-coupling radii can cause the destruction of the effective spatial inversion symmetry, which gives rise to the valley Hall phase transition and the forming of topological edge states. Utilizing valley Hall effect, topological transports of elastic waves traveling along linear and Z-shaped waveguides are realized with low scattering and immunity to defects. On this basis, the path-selection function of transports of elastic waves in periodic triangular-lattice structures is obtained. Topological valley Hall edge states of elastic waves in periodic triangular-lattice structures have a good application prospects in elastic-wave manipulations and communications. [ABSTRACT FROM AUTHOR]

Cardiac ischemia, hypoxia, arrhythmias, and heart failure share the common electrophysiological changes featured by the elevation of intracellular Ca2+ (Ca2+ overload) and inhibition of the inward rectifier potassium (IK1) channel. IK1 channel agonists have been considered a new type of anti‐arrhythmia and cardioprotective agents. We predicted using a drug repurposing strategy that tetramisole (Tet), a known anthelminthic agent, was a new IK1 channel agonist. The present study aimed to experimentally identify the above prediction and further demonstrate that Tet has cardioprotective effects. Results of the whole‐cell patch clamp technique showed that Tet at 1–100 μmol/L enhanced IK1 current, hyperpolarized resting potential (RP), and shortened action potential duration (APD) in isolated rat cardiomyocytes, while without effects on other ion channels or transporters. In adult Sprague–Dawley (SD) rats in vivo, Tet showed anti‐arrhythmia and anticardiac remodeling effects, respectively, in the coronary ligation‐induced myocardial infarction model and isoproterenol (Iso, i.p., 3 mg/kg/day, 10 days) infusion‐induced cardiac remodeling model. Tet also showed anticardiomyocyte remodeling effect in Iso (1 μmol/L) infused adult rat ventricular myocytes or cultured H9c2 (2‐1) cardiomyocytes. Tet at 0.54 mg/kg in vivo or 30 μmol/L in vitro showed promising protections on acute ischemic arrhythmias, myocardial hypertrophy, and fibrosis. Molecular docking was performed and identified the selective binding of Tet with Kir2.1. The cardioprotection of Tet was associated with the facilitation of IK1 channel forward trafficking, deactivation of PKA signaling, and inhibition of intracellular calcium overload. Enhancing IK1 may play dual roles in anti‐arrhythmia and antiventricular remodeling mediated by restoration of Ca2+ homeostasis. [ABSTRACT FROM AUTHOR]

Rotational spectra of 2,2,3,3,3-pentafluoro-1-propanol (PFP) were measured using cavity and chirped pulse Fourier transform microwave spectrometers. Of the nine possible PFP configurations which include four mirror-imaged pairs and an achiral conformer, the two most stable monomeric PFP imaged pairs, i.e., PFPG+g+/G−g− and PFPTg+/Tg− were observed and assigned, along with the 13C, 18O and deuterated isotopologues of PFPG+g+/G−g−. The rotational transitions of PFPTg+/Tg− exhibit large tunnelling splittings and were analyzed in detail. CREST, a recently developed conformational search tool that was used for systematic conformational searches of possible binary PFP conformers and the subsequent DFT calculations at the B3LYP-D3(BJ)/def2-QZVP level produced nearly 80 stable, binary PFP geometries, where ten of them are within a narrow energy window of ∼1 kJ mol−1, highlighting the structural diversity of the system. Rotational spectra of five (PFP)2 conformers were assigned and were identified as the five most stable binary conformers predicted. A closer examination reveals that the assigned binary conformers are made exclusively of the two most stable PFP monomeric subunits observed experimentally. A combined kinetic and thermodynamic model was proposed to explain the observation or non-observation of low energy conformers, and the analysis was further verified by the 'argon test'. The non-covalent intermolecular interactions of PFP and its binary conformers are also discussed with the aid of quantum theory of atoms in molecules (QTAIM) and non-covalent interaction (NCI) analyses, as well as the effects of fluorination by comparing with 1-propanol and its dimers. [ABSTRACT FROM AUTHOR]

This paper discusses the planar closed orbits of the three-dimensional autonomous system where P, Q and R are polynomials with { P, Q, R} = 2. We demonstrate that this system would not have any planar closed orbit for some coefficients. [ABSTRACT FROM AUTHOR]

Objective: The aim was to assess the effects of various antiarrhythmic drugs on 2,4-dinitrophenol (DNP) induced outward current (IDNP), presumably the ATP sensitive K+ current (IK,ATP), of isolated cardiac cells and to discuss mechanisms involved in the hypoglycaemia which occurs in patients on these drugs. Methods: The quasi-steady state current-voltage relationship from the isolated guinea pig ventricular cells was measured using whole cell voltage clamp techniques with a ramp pulse programme. The effects of seven different antiarrhythmic drugs on IDNP were examined. Action potentials were elicited at a rate of 0.2 Hz by an intracellular current injection. Results: DNP (50 μmol·litre−1) increased the quasi-steady state outward current at potentials positive to about -60 mV. This current (IDNP) was completely inhibited by the subsequent application of glibenclamide (1 μmol·litre−1), thereby suggesting that the IDNP is probably IK,ATP. Cibenzoline (10 μmol·litre−1, class Ia), disopyramide (30 μmol·litre−1, class Ia), and procainamide (100 μmol·litre−1, class Ia) significantly inhibited the IDNP by 95.5(SD 11.3)%, 77.8(21.2)%, and 76.4(23.9)% respectively. Flecainide (class Ic) inhibited the IDNP by 66.9(23.9)% at 10 μmol·litre−1 but not at 2 μmol·litre−1. Mexiletine (30 μmol·litre−1, class Ib), pilsicainide (50 μmol·litre−1, class Ic), and E4031 (10 μmol·litre−1, class III) at concentrations as high as approximately fivefold the clinically effective blood levels, did not suppress IDNP. Except for 10 μmol·litre−1 flecainide, all the concentrations listed above which blocked IDNP were within twofold of the clinical blood concentrations ducumented to be effective for suppression of arrhythmias. Cibenzoline, disopyramide, and procainamide, but not flecainide, belong to class la antiarrhythmic drugs. All these class la antiarrhythmic drugs "shortened" the action potential duration of guinea pig ventricular cells, an opposite change to that noted for multicellular preparations, eg, guinea pig papillary muscles. Conclusions: Class la antiarrhythmic drugs (cibenzoline, disopyramide, and procainamide) inhibit IDNP (presumably IK,ATP) in guinea pig ventricular cells within a range of therapeutic concentrations. This inhibitory effect of IK,ATP can probably explain the hypoglycaemia which occurs in some patients receiving these drugs, and the prolongation of the action potential duration alleged to occur in "superfused" papillary muscles.Cardiovascular Research 1992;26:1095-1101 [ABSTRACT FROM PUBLISHER]

Arrhythmogenesis of chronic myocardial infarction (MI) is associated with the prolongation of action potential, reduction of inward rectifier potassium (I K1 , Kir) channels and hyper-activity of Calcium/calmodulin-dependent kinase II (CaMKII) in cardiomyocytes. Zacopride, a selective I K1 agonist, was applied to clarify the cardioprotection of I K1 agonism via a CaMKII signaling on arrhythmias post-MI. Male SD rats were implanted wireless transmitter in the abdominal cavity and subjected to left main coronary artery ligation or sham operation. The telemetric ECGs were monitored per day throughout 4 weeks. At the endpoint, isoproterenol (1.28 mg/kg, i.v.) was administered for provocation test. The expressions of Kir2.1 (dominant subunit of I K1 in ventricle) and CaMKII were detected by Western-blotting. In the telemetric rats post-MI, zacopride significantly reduced the episodes of atrioventricular conduction block (AVB), premature ventricular contraction (PVC), ventricular tachycardia (VT) and ventricular fibrillation (VF), without significant effect on superventricular premature contraction (SPVC). In provocation test, zacopride suppressed the onset of ventricular arrhythmias in conscious PMI or sham rats. The expression of Kir2.1 was significantly downregulated and p -CaMKII was upregulated post-MI, whereas both were restored by zacopride treatment. I K1 /Kir2.1 might be an attractive target for pharmacological controlling of lethal arrhythmias post MI. [ABSTRACT FROM AUTHOR]