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Photo-assisted Zn-air batteries can accelerate the kinetics of oxygen reduction and oxygen evolution reactions (ORR/OER); however, challenges such as rapid charge carrier recombination and continuous electrolyte evaporation remain. Herein, for the first time, piezoelectric catalysis is introduced in a photo-assisted Zn-air battery to improve carrier separation capability and accelerate the ORR/OER kinetics of the photoelectric cathode. The designed microhelical catalyst exploits simple harmonic vibrations to regenerate the built-in electric field continuously. Specifically, in the presence of the low-frequency kinetic energy that occurs during water flow, the piezoelectric-photocoupling catalyst of poly(vinylidene fluoride-co-trifluoroethylene)@ferric oxide(Fe@P(V-T)) is periodically deformed, generating a constant reconfiguration of the built-in electric field that separates photogenerated electrons and holes continuously. Further, on exposure to microvibrations, the gap between the charge and discharge potentials of the Fe@P(V-T)-based photo-assisted Zn-air battery is reduced by 1.7 times compared to that without piezoelectric assistance, indicating that piezoelectric catalysis is highly effective for enhancing photocatalytic efficiency. This study provides a thorough understanding of coupling piezoelectric polarization and photo-assisted strategy in the field of energy storage and opens a fresh perspective for the investigation of multi-field coupling-assisted Zn-air batteries.

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BACKGROUND: The consistency of pancreatic apparent diffusion coefficient (ADC) values and intravoxel incoherent motion (IVIM) parameter values across different magnetic resonance imaging (MRI) devices significantly impacts the patient's diagnosis and treatment. AIM: To explore consistency in image quality, ADC values, and IVIM parameter values among different MRI devices in pancreatic examinations. METHODS: This retrospective study was approved by the local ethics committee, and informed consent was obtained from all participants. In total, 22 healthy volunteers (10 males and 12 females) aged 24-61 years (mean, 28.9 ± 2.3 years) underwent pancreatic diffusion-weighted imaging using 3.0T MRI equipment from three vendors. Two independent observers subjectively scored image quality and measured the pancreas's overall ADC values and signal-to-noise ratios (SNRs). Subsequently, regions of interest (ROIs) were delineated for the IVIM parameters (true diffusion coefficient, pseudo-diffusion coefficient, and perfusion fraction) using post-processing software. These ROIs were on the head, body, and tail of the pancrease. The subjective image ratings were assessed using the kappa consistency test. Intraclass correlation coefficients (ICCs) and mixed linear models were used to evaluate each device's quantitative parameter values. Finally, a pairwise analysis of IVIM parameter values across each device was performed using Bland-Altman plots. RESULTS: The Kappa value for the subjective ratings of the different observers was 0.776 (P < 0.05). The ICC values for inter-observer and intra-observer agreements for the quantitative parameters were 0.803 [95% confidence interval (CI): 0.684-0.880] and 0.883 (95%CI: 0.760-0.945), respectively (P < 0.05). The ICCs for the SNR between different devices was comparable (P > 0.05), and the ICCs for the ADC values from different devices were 0.870, 0.707, and 0.808, respectively (P < 0.05). Notably, only a few statistically significant inter-device agreements were observed for different IVIM parameters, and among those, the ICC values were generally low. The mixed linear model results indicated differences (P < 0.05) in the f-value for the pancreas head, D-value for the pancreas body, and D-value for the pancreas tail obtained using different MRI machines. The Bland-Altman plots showed significant variability at some data points. CONCLUSION: ADC values are consistent among different devices, but the IVIM parameters' repeatability is moderate. Therefore, the variability in the IVIM parameter values may be associated with using different MRI machines. Thus, caution should be exercised when using IVIM parameter values to assess the pancreas.

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The lack of stable solid-state electrolytes (SSEs) with high-ionic conductivity and rational design of electrode/electrolyte interfaces remains challenging for solid-state lithium batteries. Here, for the first time, a high-performance solid-state lithium-oxygen battery is developed based on the Li-ion-conducted hydrogen-bonded organic framework (LHOF) electrolyte and the core-shell HOF-DAT@CNT cathode with a few layers of HOF-DAT on surface of carbon nanotubes. Benefiting from the abundant dynamic hydrogen bonding network in LHOF-DAT SSEs, fast Li+ ion transport (2.2 × 10-4 S cm-1), a high Li+ transfer number (0.88), and a wide electrochemical window of 5.05 V are achieved. Symmetric batteries constructed with LHOF-DAT SSEs exhibit a stably cycled duration of over 1400 h, which mainly stems from the jumping sites that promote a uniformly high rate of Li+ flux and the hydrogen-bonding network structure that can relieve the structural changes during Li+ transport. LHOF-DAT SSEs-based Li-O2 batteries exhibit high specific capacity (10335 mAh g-1), and stable cycling life up to 150 cycles. Moreover, the solid-state lithium metal battery with LHOF-DAT SSEs endow good rate capability (128.8 mAh g-1 at 1 C), long-term discharge/charge stability (210 cycles). The design of LHOF-DAT SSEs opens an avenue for the development of novel SSEs-based solid-state lithium batteries.

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Chemically self-recharging zinc ion batteries (ZIBs), which are capable of auto-recharging in ambient air, are promising in self-powered battery systems. Nevertheless, the exclusive reliance on chemical energy from oxygen for ZIBs charging often would bring some obstacles in charging efficiency. Herein, we develop photo-assisted chemically self-recharging aqueous ZIBs with a heterojunction of MoS2/SnO2 cathode, which are favorable to enhancing both the charging and discharging efficiency as well as the chemical self-charging capabilities under illumination. The photo-assisted process promotes the electron transfer from MoS2/SnO2 to oxygen, accelerating the occurrence of the oxidation reaction during chemical self-charging. Furthermore, the electrons within the MoS2/SnO2 cathode exhibit a low transfer impedance under illumination, which is beneficial to reducing the migration barrier of Zn2+ within the cathode and thereby facilitating the uniform inserting of Zn2+ into MoS2/SnO2 cathode during discharging. This photo-assisted chemical self-recharging mechanism enables ZIBs to attain a maximum self-charging potential of 0.95 V within 3 hours, a considerable self-charging capacity of 202.5 mAh g-1 and excellent cycling performance in a self-charging mode. This work not only provides a route for optimizing chemical self-charging energy storage, but also broadens the potential application of aqueous ZIBs.

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Bouncing dynamics of a trailing drop off-center impacting a leading drop with varying time intervals and Weber numbers are investigated experimentally. Whether the trailing drop impacts during the spreading or receding process of the leading drop is determined by the time interval. For a short time interval of 0.15 ≤ Δt* ≤ 0.66, the trailing drop impacts during the spreading of the leading drop, and the drops completely coalesce and rebound; for a large time interval of 0.66 < Δt* ≤ 2.21, the trailing drop impacts during the receding process, and the drops partially coalesce and rebound. Whether the trailing drop directly impacts the surface or the liquid film of the leading drop is determined by the Weber number. The trailing drop impacts the surface directly at moderate Weber numbers of 16.22 ≤ We ≤ 45.42, while it impacts the liquid film at large Weber numbers of 45.42 < We ≤ 64.88. Intriguingly, when the trailing drop impacts the surface directly or the receding liquid film, the contact time increases linearly with the time interval but independent of the Weber number; when the trailing drop impacts the spreading liquid film, the contact time suddenly increases, showing that the force of the liquid film of the leading drop inhibits the receding of the trailing drop. Finally, a theoretical model of the contact time for the drops is established, which is suitable for different impact scenarios of the successive off-center impact. This study provides a quantitative relationship to calculate the contact time of drops successively impacting a superhydrophobic surface, facilitating the design of anti-icing surfaces.

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Alzheimer's disease (AD) comprises a group of neurodegenerative disorders with some changes in the brain, which could lead to the deposition of certain proteins and result in the degeneration and death of brain cells. Patients with AD manifest primarily as cognitive decline, psychiatric symptoms, and behavioural disorders. Short-chain fatty acids (SCFAs) are a class of saturated fatty acids (SFAs) produced by gut microorganisms through the fermentation of dietary fibre ingested. SCFAs, as a significant mediator of signalling, can have diverse physiological and pathological roles in the brain through the gut-brain axis, and play a positive effect on AD via multiple pathways. Firstly, differences in SCFAs and microbial changes have been stated in AD cases of humans and mice in this paper. And then, mechanisms of three main SCFAs in treating with AD have been summarized, as well as differences of gut bacteria. Finally, functions of SCFAs played in regulating intestinal flora homeostasis, modulating the immune system, and the metabolic system, which were considered to be beneficial for the treatment of AD, have been elucidated, and the key roles of gut bacteria and SCFAs were pointed out. All in all, this paper provides an overview of SCFAs and gut bacteria in AD, and can help people to understand the importance of gut-brain axis in AD.

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Organoboron compounds demonstrate diverse applications in the fields of organic synthesis, materials science, and medicinal chemistry. Compared to the conventional hydroboration reaction, radical hydroboration serves as an alternative approach for the synthesis of organoborons via different mechanisms. In radical hydroboration, a boryl radical is initially generated from homolytic cleavage of a B-H or a B-B bond, which is then added to an unsaturated double bond to deliver a carbon radical. Subsequent hydrogen atom transfer or reduction of the carbon radical to form a carbanion followed by protonation gave the final product. Over the past few years, numerous efforts have been made for efficient synthesis of boryl radicals and the expansion of substrate scope of the radical hydroboration reaction. Here, we discuss the recent advancement of radical hydroboration and its associated mechanisms. Numerous radical hydroboration strategies employing N-heterocyclic carbene borane, bis(pinacolato)diboron and pinacolborane as the boron source were illustrated. Thermochemical, photochemical and electrochemical strategies for the generation of boryl radicals were also discussed in detail.

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Cascade radical cyclization constitutes an atom- and step-economic route for rapid assembly of polycyclic molecular skeletons. Although an array of redox-active metal catalysts has recently shown robust applications in enabling various catalytic cascade radical processes, the use of free organic radical as the catalyst, which is capable of triggering strategically distinct cascades, has rarely been developed. Here, we disclosed that the benzimidazolium-based N-heterocyclic carbene (NHC)-boryl radical is capable of catalyzing cascade cyclization reactions in both intra- and intermolecular pathways, assembling [5,5] fused bicyclic and [6,6,6] fused tricyclic molecules, respectively. The catalytic reactions start with the chemo- and regioselective addition of the boryl radical catalyst to a tethered alkene or alkyne moiety, followed by either an intramolecular formal [3+2] or an intermolecular [2+2+2] cycloaddition process to construct bicyclo[3.3.0]octane or tetrahydrophenanthridine skeletons, respectively. Eventually, a ß-elimination occurs to release the boryl radical catalyst, completing a catalytic cycle. High to excellent diastereoselectivity is achieved in both catalytic reactions under substrate control.

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INTRODUCTION: Pulmonary metastasectomy has been clarified in improving long-term survival in most primary malignancies with pulmonary metastasis, while the role of additional lymph node dissection remained controversial. We aimed to investigate the prognosis of lymph node involvement and identify the role of lymph node dissection during pulmonary metastasectomy in a real-world cohort. METHODS: We identified patients diagnosed with pulmonary metastases with ≤3 cm in size and received pulmonary metastasectomy between 2004 and 2017 in the Surveillance, Epidemiology, and End Results database. We compared the survival via Kaplan-Meier analysis and propensity score matching method, and the multivariable analysis was conducted by cox regression analysis. RESULTS: A total of 3452 patients were included, of which 2268(65.7%) received lymph node dissection, and the incidence of node-positive was 11.3%(256/2268). In total, the median overall survival was 62.8 months(interquartile range, 28.6-118.9 months), and the lymph node involvement was referred to an impaired survival compared to node-negative diseases(5-year overall survival rate, 58.0% versus 38.6%), with comparable survival between N1 and N2 diseases(P = 0.774). Lymph node dissection was associated with improved survival(HR = 0.80; 95%CI, 0.71-0.90; P < 0.001), and the survival benefits remained regardless of age, sex, the number of metastases, and surgical procedures, even in those with node-negative diseases. At least eight LNDs might lead to a significant improvement in survival, and additional survival benefits might be limited with additional dissected lymph nodes. CONCLUSIONS: Lymph node involvement was associated with impaired survival, and lymph node dissection during pulmonary metastasectomy could improve long-term survival and more accurate staging.

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Minimally invasive surgery is a kind of surgical operation, which is performed by using professional surgical instruments and equipment to inactivate, resect, repair or reconstruct the pathological changes, deformities and wounds in human body through micro-trauma or micro-approach, in order to achieve the goal of treatment, its surgical effect is equivalent to the traditional open surgery, while avoiding the morbidity of conventional surgical wounds. In addition, it also has the advantages of less trauma, less blood loss during operation, less psychological burden and quick recovery on patients, and these minimally invasive techniques provide unique value for the examination and treatment of gastric cancer patients. Surgical minimally invasive surgical techniques have developed rapidly and offer numerous options for the treatment of early gastric cancer (EGC): endoscopic mucosal resection (EMR), underwater EMR (UEMR), endoscopic submucosal dissection (ESD), endoscopic full-thickness resection (EFTR), endoscopic submucosal excavation (ESE), submucosal tunnel endoscopic resection), laparoscopic and endoscopic cooperative surgery (LECS); Among them, EMR, EFTR and LECS technologies have a wide range of applications and different modifications have been derived from their respective surgical operations, such as band-assisted EMR (BA-EMR), conventional EMR (CEMR), over-the-scope clip-assisted EFTR, no-touch EFTR, the inverted LECS, closed LECS, and so on. These new and improved minimally invasive surgeries are more precise, specific and effective in treating different types of EGC.

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Electrochemistry that empowers innovative nanoscopic analysis has long been pursued. Here, the concept of aggregation-enabled electrochemistry (AEE) in a confined nanopore is proposed and devised by reactive oxygen species (ROS)-responsive aggregation of CdS quantum dots (QDs) within a functional nanopipette. Complementary Faradaic and non-Faradaic operations of the CdS QDs aggregate could be conducted to simultaneously induce the signal-on of the photocurrents and the signal-off of the ionic signals. Such a rationale permits the cross-checking of the mutually corroborated signals and thus delivers more reliable results for single-cell ROS analysis. Combined with the rich biomatter-light interplay, the concept of AEE can be extended to other stimuli-responsive aggregations for electrochemical innovations.

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Li-CO2 batteries have received significant attention owing to their advantages of combining greenhouse gas utilization and energy storage. However, the high kinetic barrier between gaseous CO2 and the Li2CO3 product leads to a low operating voltage (<2.5 V) and poor energy efficiency. In addition, the reversibility of Li2CO3 has always been questioned owing to the introduction of more decomposition paths caused by its higher charging plateau. Here, a novel "trinity" Li-CO2 battery system was developed by synergizing CO2, soluble redox mediator (2,2,6,6-tetramethylpiperidoxyl, as TEM RM), and reduced graphene oxide electrode to enable selective conversion of CO2 to Li2C2O4. The designed Li-CO2 battery exhibited an output plateau reaching up to 2.97 V, higher than the equilibrium potential of 2.80 V for Li2CO3, and an ultrahigh round-trip efficiency of 97.1 %. The superior performance of Li-CO2 batteries is attributed to the TEM RM-mediated preferential growth mechanism of Li2C2O4, which enhances the reaction kinetics and rechargeability. Such a unique design enables batteries to cope with sudden CO2-deficient environments, which provides an avenue for the rationally design of CO2 conversion reactions and a feasible guide for next-generation Li-CO2 batteries.

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Chiral diarylmethylamides are a privileged skeleton in many bioactive molecules. However, the enantioselective synthesis of such molecules remains a long-standing challenge in organic synthesis. Herein, we report a chiral bifunctional squaramide catalyzed asymmetric aza-Michael addition of amides to in situ generated ortho-quinomethanes, affording enantioenriched diarylmethylamides in good yields with excellent enantioselectivities. This work not only provides a new strategy for the construction of the diarylmethylamides but also represents the practicability of amides as nitrogen-nucleophiles in asymmetric organocatalysis.

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Enantioselective synthesis of eight-membered N-heterocycles represents a long-standing challenge in organic synthesis. Here, by combining the squaramide and DBU catalysis, a sequential asymmetric conjugate addition/cyclization reaction between benzofuran-derived azadienes and ynones has been well-developed, providing straightforward access to chiral eight-membered N-heterocycles in high yields with stereoselectivities. This protocol features the use of a bifunctional squaramide catalyst for controlling the enantioselectivity of products, while the DBU is utilized to achieve intramolecular cyclization and improve the diastereoselectivity of products.

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Aprotic lithium-oxygen (Li-O2) batteries are considered to be a promising alternative option to lithium-ion batteries for high gravimetric energy storage devices. However, the sluggish electrochemical kinetics, the passivation, and the structural damage to the cathode caused by the solid discharge products have greatly hindered the practical application of Li-O2 batteries. Herein, the nonsolid-state discharge products of the off-stoichiometric Li1-xO2 in the electrolyte solutions are achieved by iridium (Ir) single-atom-based porous organic polymers (termed as Ir/AP-POP) as a homogeneous, soluble electrocatalyst for Li-O2 batteries. In particular, the numerous atomic active sites act as the main nucleation sites of O2-related discharge reactions, which are favorable to interacting with O2-/LiO2 intermediates in the electrolyte solutions, owing to the highly similar lattice-matching effect between the in situ-formed Ir3Li and LiO2, achieving a nonsolid LiO2 as the final discharge product in the electrolyte solutions for Li-O2 batteries. Consequently, the Li-O2 battery with a soluble Ir/AP-POP electrocatalyst exhibits an ultrahigh discharge capacity of 12.8 mAh, an ultralow overpotential of 0.03 V, and a long cyclic life of 700 h with the carbon cloth cathode. The manipulation of nonsolid discharge products in aprotic Li-O2 batteries breaks the traditional growth mode of Li2O2, bringing Li-O2 batteries closer to being a viable technology.

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Reducing the contact time during the droplet impact on the surface is crucial for anti-icing, self-cleaning, and heat transfer optimization applications. This study aims to minimize the contact time by modifying the surface curvature to create an asymmetric impact process. Our experiments showed that the increase in Weber numbers (We) and the decrease in the ratio of surface diameter to droplet diameter (D*) intensify the asymmetry of the impact process, yielding four distinct rebound modes. Low asymmetry observes the liquid retract toward the central point (Rebound Modes 1 and 2), whereas high asymmetry yields a wing-like rebound (Rebound Modes 3 and 4). In Rebound Mode 1, increased asymmetry would lead to more extended contact due to the prolonged waiting period. Conversely, the reduction in contact time in Rebound Mode 2 occurs due to increased asymmetry with no waiting period. For Rebound Modes 3 and 4, the retraction time could be divided into three stages, generated by two liquid detachment modes from the surface. Analysis reveals that an increased asymmetry would reduce the retraction time during the first stage but prolong it during the third stage, with no significant effects on the second. Four correlations, each pertaining to a distinct impact mode, are proposed based on these analyses to describe the contact time concerning We and D* for droplets impacting a superhydrophobic cylindrical surface.

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This study investigates whether adding ridges to a superhydrophobic cylindrical surface can reduce contact times compared to those of ridged flat or cylindrical surfaces, inspired by the shortened contact time achieved by adding ridges to flat surfaces. The study focuses on studying azimuthal ridges on the cylinder through experimentation, emphasizing the impact dynamics and contact time characteristics under varying We (Weber number) and D* (dimensionless droplet diameter). Within the ultralow Weber number range (ULWR), low Weber number range (LWR), and medium Weber number range (MWR), the contact time is longer than on ridged flat surfaces. In the high Weber number range (HWR), the opposite is observed: increased inertial forces lead to the rupture of the liquid film above the ridges due to Rayleigh-Plateau instability. As a result, the primary droplet splits into two sections with curvature effects promoting its recoiling and rebounding. This study introduces a criterion, defined as C = We/D*, and finds that when C exceeds 2.42, not only is the contact time shorter than on ridged flat or cylindrical surfaces, but it also further decreases with an increase in We or a decrease in D*. The contact time characteristics observed in the HWR offer potential applications in areas such as anti-icing.

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Extensive research has shown that a superhydrophobic cylindrical substrate could lead to a noncircumferential symmetry of an impacting droplet, reducing the contact time accordingly. It is of practical significance in applications, such as anti-icing, anticorrosion, and antifogging. However, few accounts have adequately addressed the off-centered impact of the droplet, despite it being more common in practice. This work investigates the dynamic behavior of a droplet off-centered impacting a superhydrophobic cylinder via the lattice Boltzmann method. The effect of the off-centered distance is primarily discussed for droplets taking various Weber numbers and cylinder sizes. The results show that the imposition of an off-center distance can further disrupt the droplet symmetry during the impact. As the off-center distance increases, the droplet movement is gradually tilted toward the offset side until it tangentially passes the cylinder side, resulting in a direct dripping mode. The dynamic features, focusing mainly on maximum spreading in the axial direction and contact time, are specifically explored. A quantitative model of the maximum spreading factor is proposed based on the equivalent transformation from the off-center impact into oblique hitting, considering the full range of off-centered distance. A preliminary contact time model is established for droplet off-centered impacting superhydrophobic cylinders by substituting the maximum spreading and the effective velocity of the liquid moving. This work aims to make an original contribution to the fundamental knowledge of droplet impact and could be of value for related applications.

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The development of functionally distinct catalysts for enantioselective synthesis is a prominent yet challenging goal of synthetic chemistry. In this work, we report a family of chiral N-heterocyclic carbene (NHC)-ligated boryl radicals as catalysts that enable catalytic asymmetric radical cycloisomerization reactions. The radical catalysts can be generated from easily prepared NHC-borane complexes, and the broad availability of the chiral NHC component provides substantial benefits for stereochemical control. Mechanistic studies support a catalytic cycle comprising a sequence of boryl radical addition, hydrogen atom transfer, cyclization, and elimination of the boryl radical catalyst, wherein the chiral NHC subunit determines the enantioselectivity of the radical cyclization. This catalysis allows asymmetric construction of valuable chiral heterocyclic products from simple starting materials.

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Using molecular dynamics simulations, we investigate the air hole formation of water nanodroplets impacting hydrophilic to hydrophobic surfaces in the range of static contact angles from 30° to 140° with different initial surface temperatures ranging from 300 to 1000 K. We show that the hole dynamics of nanodroplets are different from those observed in millimeter-sized droplets. The hole formation can be observed on smooth surfaces for nanodroplets; however, it only occurs on nonsmooth surfaces for millimeter-sized droplets. We clarify that the hole formation of nanodroplets is triggered by a nucleated vapor bubble due to thermodynamic instability, whereas it is initiated by air bubble entrapment during impact due to hydrodynamic instability for millimeter-sized droplets. The hole formation of nanodroplets relies heavily on the surface temperature and surface wettability, because the nucleated vapor bubble more easily occurs and grows on the surface with high initial temperatures and hydrophobic surfaces. Based on the thermal stability analysis, a criterion is developed to predict the hole formation of nanodroplets, which verifies the dependence of hole formation on the surface temperature and wettability. Furthermore, we show that the ring-bouncing of nanodroplets is triggered by the nucleated vapor bubble. We clarify the reasons for the reduced contact time of nanodroplets caused by the ring-bouncing.