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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]

A characterization of non-metallic inclusions in Fe-Mn-Si-Al twinning-induced plasticity (TWIP) steels during argon oxygen decarburization-electroslag remelting-forging (AOD-ESR-forging) process has been performed. The two main kinds of inclusions found in TWIP-AOD ingots are single Al(O)N and MnS(Se)-Al(O)N aggregates. After the ESR process, Al(O)N and MnS(Se) inclusions in all size ranges significantly decrease while other kinds of inclusions show only minor changes. In the present study, the precipitation, growth, and dissolution of AlN and MnS inclusions have been analyzed by thermodynamics and kinetics. It is found that AlN inclusions in TWIP steels can already precipitate in the liquid. Furthermore, AlN inclusions precipitated in the liquid TWIP steels can act as the heterogeneous nuclei of MnS inclusions, and thus forming Al(O)N and MnS(Se) · Al(O)N clusters. After ESR refining, the precipitation temperature of AlN and MnS inclusions will be significantly decreased, and AlN inclusions cannot be formed in the liquid TWIP steels in particular. The kinetic analysis show that the growth of AlN inclusions will be difficult during the ESR process, because their growth rate decreases significantly, while the dissolution rate increases. [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]

Cardiac ischemia, hypoxia, arrhythmias, and heart failure share the common electrophysiological changes featured by the elevation of intracellular Ca 2+ (Ca 2+ overload) and inhibition of the inward rectifier potassium (I K1 ) channel. I K1 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 I K1 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 I K1 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 I K1 channel forward trafficking, deactivation of PKA signaling, and inhibition of intracellular calcium overload. Enhancing I K1 may play dual roles in anti-arrhythmia and antiventricular remodeling mediated by restoration of Ca 2+ homeostasis., (© 2022 The Authors. Pharmacology Research & Perspectives published by British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics and John Wiley & Sons Ltd.)

Liaoyu white cattle (LYWC) is a local breed in Liaoning Province, China. It has the advantages of grow quickly, high slaughter ratew, high meat quality and strong anti-stress ability. N 6 methyladenosine (m6A) is a methylation modification of N 6 position of RNA adenine, which is an important modification mechanism affecting physiological phenomena. In this study, we used the longissimus dorsi muscle of LYWC and SIMC for m6A-seq and RNA-seq high-throughput sequencing, and identified the key genes involved in muscle growth and m6A modification development by bioinformatics analysis. There were 31532 m6A peaks in the whole genome of LYWC and 47217 m6A peaks in the whole genome of SIMC. Compared with Simmental cattle group, LYWC group had 17,351 differentially expressed genes: 10,697 genes were up-regulated, 6,654 genes were down regulated, 620 differentially expressed genes were significant, while 16,731 differentially expressed genes were not significant. Among the 620 significantly differentially expressed genes, 295 genes were up-regulated and 325 genes were down regulated. In order to explore the relationship between m6A and mRNA expression in the muscles of LYWC and SIMC, the combined analysis of MeRIP-seq and RNA-seq revealed that 316 genes were m6A modified with mRNA expression. To identify differentially methylated genes related to muscle growth, four related genes were selected for quantitative verification in LYWC and SIMC. GO enrichment and KEGG analysis showed that the differentially expressed genes modified by m6A are mainly involved in skeletal muscle contraction, steroid biosynthesis process, redox process, PPAR pathway and fatty acid metabolism, and galactose metabolism. These results provide a theoretical basis for further research on the role of m6A in muscle growth and development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Dang, Dong, Wu, Yang, Sun, Cui, Xu, Zhao, Zhang, Li and Li.)

Rotational spectra of the 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP)···water complex were measured using a chirped pulse Fourier-transform microwave spectrometer. The spectral analyses, aided by density functional theory calculations, reveal two HFIP···water isomers: one previously reported, trans HFIP (HFIP t )···water ( Phys. Chem. Chem. Phys. 2015, 119, 5650-5657), and a new isomer, gauche HFIP (HFIP g )···water. To confirm the identity of the new isomer, rotational spectra of seven of its deuterated species were also measured and analyzed. Both the experimental and theoretical pieces of evidence indicate that the intermolecular interaction with water preferentially stabilizes the HFIP g monomer configuration over the global minimum configuration, HFIP t . The relative energy difference between these monomeric forms is 4.1 kJ mol -1 and decreases to 2.5 kJ mol -1 in the respective monohydrates at the B3LYP-D3(BJ)/def2-QZVP level of theory. Both rigid and relaxed potential energy surface scans were carried out to gain insights into the large-amplitude water motions in HFIP g ···water. The nonobservation of a water tunneling splitting in HFIP t ···water has been explained to be a result of a barrier-less (after zero-point-energy correction) pathway for the water motion, whereas in HFIP g ···water, a relatively large water tunneling barrier was identified as the cause of barely resolved water tunneling splittings. Noncovalent interaction and quantum theory of atoms and molecule analyses were used to evaluate the changes in HFIP g ···water when going from the minimum to the transition state in terms of attractive interactions such as the OH···H and OH···F contacts. The effect of fluorination is discussed by comparing the vastly different binding topologies of isopropanol···water and HFIP···water.

For most commercial photodetectors (PDs), incident light is illuminated from the top or side of the device, but the opaque electrode (gold, copper, or aluminum, etc.) on the top will block part of the light from entering, wasting the efficiency of light utilization. Herein, to solve this issue, we introduced perovskite nanonet PDs with a hollow vertical structure by using a polystyrene microsphere template. Compared with ordinary thin film devices, our reticulated hollow vertical structure devices not only can enable easy entrance of the light from the reticulated hollow surface of the devices but also can reduce the reflection of light, resulting in better device performance. For our optimal CsPbBr 3 perovskite PDs, high photoelectric performances were achieved with the switching ratio up to 4.17 × 10 4 , a detectivity of 7.44 × 10 11 Jones, a linear dynamic range of 108 dB, and the rise/fall time of 0.1/0.16 ms. More importantly, because of the reticulated hollow structure, our device performance showed less reduction when the incident light was illuminated from the top than from the bottom. These results may be of great reference value for improving the photoelectric performance of silicon-based devices or deep ultraviolet PDs.

The structures and binding topologies of two binary van der Waals complexes 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP)···Ne and ···Ar were investigated. The rotational spectra of these two complexes including several isotopic species containing 20 Ne, 22 Ne, 40 Ar, 13 C, and hydroxyl D were measured using a chirped pulse Fourier transform microwave spectrometer and a cavity-based Fourier transform microwave spectrometer. While HFIP was shown to exist in both the gauche and trans configurations based on previous reports, the rare gas atom is predicted to attach to HFIP in several different binding topologies, leading to a total of nine possible structural isomers for each complex. Only one isomer was detected for each species, and it corresponds to the most stable one predicted, based on the comparison of the experimental rotational constants and electric dipole moment components with the theoretical predictions and on the isotopic data. We applied quantum theory of atoms in molecules (QTAIM) and electrostatic potential calculations to examine the different rare gas binding sites and to explore the nature of the interactions in these two complexes and several previously reported alcohol···Ar complexes. The effects of fluorination are also discussed by comparison with the binary complexes of isopropanol···Ne and ···Ar.

Inward rectifier potassium channels (I K1 , Kir) are known to play critical roles in arrhythmogenesis. Thus, how I K1 agonist affects reperfusion arrhythmias needs to be clarified, and its underlying mechanisms should be determined. Reperfusion arrhythmias were modeled by coronary ligation (ischemia, 15 minutes) and release (reperfusion, 15 minutes). Zacopride (1.5-50 μg/kg in vivo, or 0.1-10 μmol/Lex vivo) was applied in the settings of pretreatment (3 minutes before coronary ligation) and posttreatment (5 minutes after coronary ligation). Hypoxia (45 minutes) /reoxygenation (30 minutes) model was established in cultured H9c2 (2-1) cardiomyocytes. Zacopride or KN93 was applied before hypoxia (pretreatment). In the setting of pre- or posttreatment, zacopride at 15 μg/kg in vivo or 1 μmol/Lin vitro exhibited superlative protections on reperfusion arrhythmias or intracellular calcium overload. Western blot data from ex vivo hearts or H9c2 (2-1) cardiomyocytes showed that I/R (H/R) induced the inhibition of Kir2.1 (the dominant subunit of I K1 channel in ventricle), phosphorylation and oxidation of CaMKII, downregulation of SERCA2, phosphorylation of phospholamban (at Thr17), and activation of caspase-3. Zacopride treatment (1 μmol/L) was noted to strikingly restore the expression of Kir2.1 and SERCA2 and decrease the activity of CaMKII, phospholamban, and caspase-3. These effects were largely eliminated by co-application of I K1 blocker BaCl 2 . CaMKII inhibitor KN93 attenuated calcium overload and p-PLB (Thr17) in an I K1 -independent manner. I K1 -depedent inhibition of CaMKII activity is found to be a key cardiac salvage signaling under Ca 2+ dyshomeostasis and reactive oxygen species (ROS) stress. I K1 might be a novel target for pharmacological conditioning of reperfusion arrhythmia, especially for the application after unpredictable ischemia.

Background: Zacopride, a potent antagonist of 5-HT3 receptors and an agonist of 5-HT4 receptors, is a gastrointestinal prokinetic agent. In a previous study, we discovered that zacopride selectively stimulated the inward rectifier potassium current (IK1) in the rat and that agonizing IK1 prevented or eliminated aconitine-induced arrhythmias in rats., Objective: Our aims were to confirm that the antiarrhythmic effects of zacopride are mediated by selectively enhancing IK1 in rabbits., Methods: The effects of zacopride on the function of the main ion channels were investigated using a whole-cell patch-clamp technique in rabbits. Effects of zacopride on cardiac arrhythmias were also explored experimentally both in vivo and in vitro., Results: Zacopride moderately enhanced cardiac IK1 but had no apparent action on voltage-gated sodium current (INa), L- type calcium current (ICa-L), sodium-calcium exchange current (INa/Ca), transient outward potassium current (Ito), or delayed rectifier potassium current (IK) in rabbits. Zacopride also had a marked antiarrhythmic effect in vivo and in vitro. We proved that the resting membrane potential (RMP) was hyperpolarized in the presence of 1 μmol/L zacopride, and the action potential duration (APD) at 90% repolarization (APD90) was shortened by zacopride (0.1-10 μmol/L) in a concentration- dependent manner. Furthermore, zacopride at 1 μmol/L significantly decreased the incidence of drug-induced early afterdepolarization (EAD) in rabbit ventricular myocytes., Conclusion: Zacopride is a selective agonist of rabbit cardiac IK1 and that IK1 enhancement exerts potential antiarrhythmic effects., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Metal-organic frameworks (MOFs) are promising gas adsorbents. Knowledge of the behavior of gas molecules adsorbed inside MOFs is crucial for advancing MOFs as gas capture materials. However, their behavior is not always well understood. In this work, carbon dioxide (CO 2 ) adsorption in the microporous α-Zn 3 (HCOO) 6 MOF was investigated. The behavior of the CO 2 molecules inside the MOF was comprehensively studied by a combination of single-crystal X-ray diffraction (SCXRD) and multinuclear solid-state magnetic resonance spectroscopy. The locations of CO 2 molecules adsorbed inside the channels of the framework were accurately determined using SCXRD, and the framework hydrogens from the formate linkers were found to act as adsorption sites. 67 Zn solid-state NMR (SSNMR) results suggest that CO 2 adsorption does not significantly affect the metal center environment. Variable-temperature 13 C SSNMR experiments were performed to quantitatively examine guest dynamics. The results indicate that CO 2 molecules adsorbed inside the MOF channel undergo two types of anisotropic motions: a localized rotation (or wobbling) upon the adsorption site and a twofold hopping between adjacent sites located along the MOF channel. Interestingly, 13 C SSNMR spectroscopy targeting adsorbed CO 2 reveals negative thermal expansion (NTE) of the framework as the temperature rose past ca. 293 K. A comparative study shows that carbon monoxide (CO) adsorption does not induce framework shrinkage at high temperatures, suggesting that the NTE effect is guest-specific., Competing Interests: The authors declare no competing financial interest.

The changes in excitability and autorhthmicity of bladder detrusor in experimental non-insulin dependent diabetes mellitus (NIDDM) rats were observed. Sixty-nine NIDDM rats as NIDDM group and 69 normal rats as control group were enrolled into this experimental study. At 6th, 10th, 14th, 18th, 22nd and 26th week after the rats were injected last time, the changes in the excitability and autorhthmicity of detrusor strips in vitro were observed. The results showed that the threshold of the tension which made the detrusor strips contract was significantly higher in NIDDM group (0.716 +/- 0.325 g) than in control group (0.323 +/- 0.177 g) (F = 59.63, P < 0.001). At different stages, the threshold of the tension resulting the contract of the detrusor strips in NIDDM group was also higher than in control group. At 18th week after STZ injection, the frequency of spontaneous contract of the detrusor strips in NIDDM was significantly higher than in control group (P < 0.05), whereas at 22nd week, that in NIDDM group was significantly lower than in control group (P < 0.05). It was concluded that the decreased excitability of the bladder detrusor was the earliest and most obvious changes in bladder function in diabetes rats and the autorhthmicity had also changed at the early stage of diabetic bladder.

Objective: To investigate the importance of autoimmunity against beta(1)-adrenoreceptor in the pathogenesis of dilated cardiomyopathy (DCM)., Methods: Fourteen rabbits were divided equally into two groups. Rabbits in the immunized group (n = 7) were immunized monthly for one year with synthetic peptide corresponding to the second extracellular loop of the beta(1)-adrenoreceptor and adjuvant. Control rabbits received the mixture with the same procedure as described except with a substitution of saline for the corresponding peptide. During the study period, all rabbits were bled to assay the titers of antipeptide antibody and left ventricular ejection fractions (LVEFs) were measured by emission computed tomography. At the end of experiment, invasive cardiac function was measured and morphologic examinations were done., Results: High titers of antipeptide antibody were found in the sera from immunized rabbits throughout the study period in contrast to those from control rabbits. LVEFs were significantly higher in immunized rabbits than those of the control group at the 4th and 6th month. At the end of the experiment, the maximal rates of rise and decline of ventricular pressure of the immunized group were significantly lower than those of the control group. Morphological changes were found in immunized rabbits such as the enlargement of ventricles, myofibrillar lysis and necrosis, mitochondria swelling and condensation. No obvious alterations were noted in hearts of control rabbits., Conclusion: Autoimmunity against the beta(1)-adrenoreceptor may be involved in the pathogenesis of dilated cardiomyopathy and beta(1)-adrenoreceptor antibody may play a role in the process.