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• Vegetation changes modulate temperature dynamics across 304 Chinese cities. • Vegetation impacts on urban-rural temperature gradients, 2000–2020, assessed. • 96 % of urban areas cool as vegetation increases, effect fades toward rural zones. • Urban afforestation rose by 4.35 %, cooling 67 % of cities by 0.58 °C from 2000 to 2020. • Vegetation alters urban cooling and rural warming, reducing UHI by 0.56 ± 0.35 °C. City afforestation serves as a robust strategy for thermal mitigation. Employing multisource satellite data, we explored the impact of vegetation cover on temperature dynamics across urban and rural sectors in Chinese cities. Our analysis reveals that a 1 % increase in vegetation coverage corresponds to a reduction in surface temperature by 0.099 °C to 0.102 °C in urban environments. However, the cooling effect diminishes from urban to rural areas, where increased vegetation occasionally results in warming. Further, the temperature reduction tends to stabilize at higher vegetation levels, as demonstrated in grid-based evaluations. Significantly, variations in urban population density substantially modulate these cooling effects. Over the period 2000–2020, afforestation increased vegetation coverage by 4.35 % in urban areas, which led to cooling in 67.43 % of the analyzed cities, with an average surface temperature decline of 0.58 °C. Additionally, our findings document a notable attenuation of the urban heat island (UHI) effect over time, with an average decrease of 0.56 ± 0.35 °C. This reduction primarily results from the thermoregulatory effects of changes in vegetation coverage, which cool urban areas and may warm rural ones. Our study underscores the critical role of afforestation in urban climate management and its efficacy in attenuating urban heat waves and UHI effects. [ABSTRACT FROM AUTHOR]

• An analytical framework for soft modes of rotation-cross vector metamaterial chains is proposed. • An anomalous nonlinear phenomenon is found: the polarization index of all nodes are equal. • Through adjusting the polarization index, the morphology of the vector boundary mode can be tuned. • Existence conditions of static-topological-soliton vector boundary modes are clarified. • Different collision responses of boundary modes are revealed for even- and odd-nodes chains. The boundary modes of highly distorted mechanical metamaterials exhibit obvious nonlinear effects. However the characteristics of vector boundary modes (boundary modes with two coupled components—translation and rotation) of nonlinear mechanical metamaterials have not been revealed, which severely limits their applications in vector deformation controls of robots and intelligent structures. In this work, by building the continuous and discrete models of nonlinear mechanical metamaterials with vector couplings, an analytical framework for soft modes of rotation-cross vector metamaterial chains is proposed. An anomalous nonlinear phenomenon is found, namely, the polarization indices (the ratio of displacement to the increment of rotation angle) of all nodes are equal, which is further verified by the experiment. Specially, the results show that the morphology of the vector boundary mode can be tuned through adjusting the polarization index. Based on this, existence conditions of static-topological-soliton boundary modes under couplings of translation and rotation are revealed explicitly, and the results further show that the vector boundary modes based on static-topological-solitons are robust and immune to structural imperfections, which is crucial to achieve precise vector deformation controls. These novel rules and phenomena presented in this work can provide new ideas and important bases for vector deformation controls of nonlinear mechanical metamaterials and their applications in lightweight robots and intelligent structures. [Display omitted] [ABSTRACT FROM AUTHOR]

The COVID-19 outbreak has injured the global industrial supply chain, especially China as the world's largest manufacturing base. Since 2020, China has implemented a rigorous lockdown policy, which has sternly damaged sectoral trade in export-oriented coastal areas. Fujian Province, which mainly processes imported materials, has a more profound influence. Although the COVID-19 lockdown has had some detrimental consequences on the world economy, it also had some favorable benefits on the global ecology. Previous studies have shown that the lockdown has altered the physical water quantity and quality, but the lack of total, virtual, and physical water research that combines water quantity and water quality simultaneously to pinpoint the subject and responsibility of water resources consumption and pollution. This research quantified the physical, virtual, and total water consumption and water pollution among 30 sectors in Fujian Province based on the theory of water footprint and the Economic Input-Output Life Cycle Assessment model. SDA model was then used to investigate the socioeconomic elements that underpin variations in the water footprint. The results show that after the lockdown, the physical water quantity and the physical grey WF in Fujian Province decreased by 2.6 Gm3 (−6.7%) and 0.4 Gm3 (−1.3%) respectively. The virtual water quantity decreased by 2.3 Gm3 (−4.5%), whereas the virtual grey WF rose by 1.5 Gm3 (4.3%). The total water quantity dropped by 3.3 Gm3 (−4.9%), while the grey WF increased by 1.2 Gm3 (2.5%), i.e. the COVID-19 lockdown decreases physical water quantity and improves local water quality. More than 50% of the water comes from virtual water trade outside the province (virtual water is highly dependent on external), and around 60% of the grey WF comes from physical sewage in the province. The COVID-19 lockdown reduced water outsourcing across the province (paid nonlocally decrease) but increased pollution outsourcing (paid nonlocally increase). And gross capital formation's contribution to the growth in water footprint will continue to rise. As a result, this study suggested that Fujian should take advantage of sectoral trade network to enhance the transaction of green water-intensive intermediate products, reduce the physical water consumption of blue water-intensive sectors, and reduce the external dependence on water consumption. Achieving the shared responsibility of upstream and downstream water consumption and reducing the external dependence on water in water-rich regions is crucial to solving the world's water problems. This research provides empirical evidence for the long-term effects of COVID-19 lockdown on the physical and virtual water environment. [Display omitted] • The impact of the COVID-19 lockdown on Fujian's water footprints (WFs) is explored. • The lockdown measures reduce physical water consumption with water quality improved. • Over 50% of water consumption is external and 60% of grey WF is local-based. • Fujian should leverage sectoral trade network to enhance its water sustainability. [ABSTRACT FROM AUTHOR]

Objectives The incidence of arrhythmia is associated with autoantibodies against the second extracellular loop of β 1 -adrenergic receptor (β 1 -AAbs). The current study was designed to determine the mechanisms by which arrhythmia experimentally might be induced by β 1 -AAbs. Methods Blood samples were collected from patients with varied arrhythmias or coronary heart disease (CHD) and healthy subjects. The titer of β 1 -AAbs was assessed. Passive immunization rat models with β 1 -AAbs were established to determine whether β 1 -AAbs induced arrhythmia. Conventional intracellular microelectrode technique and whole cell patch clamp were employed to record action potential duration (APD), resting potential (RP), L-type calcium current ( I Ca-L ), sodium–calcium exchange current (INCX), transient outward potassium current ( I to ), inward rectifier potassium current ( I k1 ) and delayed rectifier potassium current ( I k ). Results High levels of β 1 -AAbs were found in the sera of heart disease patients, especially in ventricular arrhythmia (VA). Transfusion with β 1 -AAbs could induce arrhythmias in normal rats in vivo. β 1 -AAbs purified from the sera of active immunized rats induced triggered activity (TA), delayed after depolarization (DAD), and prolonged APD in the papillary muscles of rats. β 1 -AAbs prolonged QT interval, increased I Ca-L and decreased I K1 , I to and I Na–Ca in rat ventricular myocytes in vitro. All these effects can be inhibited by β 1 -AR blocker metoprolol. Conclusions These results demonstrate for the first time that β 1 -AAbs could directly induce ventricular arrhythmia by prolonging QT interval. [ABSTRACT FROM AUTHOR]

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]