Long-term survival outcomes of esophagectomy with off-pump CABG versus esophagectomy alone.

BACKGROUND: This study aimed to evaluate the long-term survival outcomes of esophagectomy with off-pump coronary artery bypass grafting (OPCABG) vs. esophagectomy alone. METHODS: A total of 1798 patients who received esophagectomy between January 2010 and February 2020 were included and divided into the 38 patients who underwent OPCABG followed by esophagectomy (OP + ES group) and 1760 patients had only esophagectomy (ES group). Propensity score matching (PSM) and Cox multivariable analyses were performed to compare postoperative complications, disease-free survival (DFS), and overall survival (OS) between the two groups. RESULTS: There were 37 patients in the OP + ES group matched with 74 in the ES group. The matched OP + ES group had higher total postoperative complications than the ES group, especially more pulmonary infections (P = 0.001) and arrhythmias (P = 0.018), but no other postoperative complications were the difference. The DFS was similar and the OS was a significant difference between the matching 2 groups (log-rank, P = 0.132 and 0.04, respectively). Although pT 3/4 stage, pN (+), and tumor length > 3.0 cm were independently associated with worse OS and DFS in multivariable analysis, CAD and EF < 55% were also found to be a predictive factor for OS and DFS in univariate analysis. CONCLUSION: OPCABG followed by esophagectomy for esophageal cancer associated with coronary artery disease has equivalent DFS and recurrence pattern to esophagectomy for esophageal cancer alone, but with a disadvantage in OS.

Health risk assessment of drinking groundwater in rural areas of Ru village and surrounding areas in Wutai County, China.

Nitrate pollution in groundwater is a global environmental problem that poses risks to human health. We investigate the health risks of nitrate in rural drinking groundwater in Rucun Township and surrounding areas of Wutai County, and provide a basis for healthy drinking water. By using statistical analysis software (SPSS19) and hydrogeochemical analysis software (AqQA), a qualitative and quantitative evaluation of nitrate health risks was conducted among populations of different ages and genders through water sample collection, chemical analysis, and construction of a human health risk model (HHRA). Through research, it was found that the average concentration of nitrate in the study area is 43.99 mg/L. Groundwater is severely polluted by NO3-, and nitrate pollution areas are mainly concentrated in the main human activity areas, especially in the main agricultural production areas. The Quaternary loess layer, as a permeable layer, cannot prevent groundwater from being polluted by NO3-. Through evaluation, it is believed that there is a health risk of nitrate pollution in rural drinking groundwater in Rucun Township and surrounding areas. Health risk level: infants>children>adult females>adult males. The discovery and evaluation results can provide a basis for the prevention and control of nitrate pollution in groundwater.

Oxygen Plasma-Assisted Defect Engineering of Graphene Nanocomposites with Ultrasmall Co3O4 Nanocrystals for Monitoring Toxic Nitrogen Dioxide at Room Temperature.

Functional adjustment of graphene with metal oxide can in fact progress the affectability of graphene-based gas sensors. However, it could be a huge challenge to upgrade the detecting execution of nitrogen dioxide (NO2) sensors at room temperature. The ultrasmall size of nanocrystals (NCs) and copious defects are two key variables for moving forward gas detecting execution. Herein, we provide an effective strategy that the hydrothermal reaction is combined with room-temperature oxygen plasma treatment to prepare Co3O4 NCs and reduced graphene oxide (RGO) nanohybrids (Co3O4-RGO). Among all of Co3O4-RGO nanohybrids, Co3O4-RGO-60 W exhibits the most superior NO2 sensing properties and achieves the low-concentration detection of NO2. The sensitivity of Co3O4-RGO-60 W to 20 ppm NO2 at room temperature is the highest (72.36%). The excellent sensing properties can mainly depend on the change in the microstructure of Co3O4-RGO. Compared with Co3O4-RGO, Co3O4-RGO-60 W with oxygen plasma treatment shows more favorable properties for NO2 adsorption, including the smaller size of Co3O4 NCs, larger specific surface area, pore size, and more oxygen vacancies (OVs). Especially, OVs make the surface of NCs have a unique chemical state, which can increase active sites and improve the adsorption property of NO2. Besides, the agreeable impact of the p-p heterojunction (Co3O4 and RGO) and the doping of N molecule contribute to the improved NO2 detecting properties. It is demonstrated that the Co3O4-RGO-60 W sensor is expected to monitor NO2 at room temperature sensitively.

Ultrasonic-Assisted Method for the Preparation of Carbon Nanotube-Graphene/Polydimethylsiloxane Composites with Integrated Thermal Conductivity, Electromagnetic Interference Shielding, and Mechanical Performances.

Due to the rapid development of the miniaturization and portability of electronic devices, the demand for polymer composites with high thermal conductivity and mechanical flexibility has significantly increased. A carbon nanotube (CNT)-graphene (Gr)/polydimethylsiloxane (PDMS) composite with excellent thermal conductivity and mechanical flexibility is prepared by ultrasonic-assisted forced infiltration (UAFI). When the mass ratio of CNT and Gr reaches 3:1, the thermal conductivity of the CNT-Gr(3:1)/PDMS composite is 4.641 W/(m·K), which is 1619% higher than that of a pure PDMS matrix. In addition, the CNT-Gr(3:1)/PDMS composite also has excellent mechanical properties. The tensile strength and elongation at break of CNT-Gr(3:1)/PDMS composites are 3.29 MPa and 29.40%, respectively. The CNT-Gr/PDMS composite also shows good performance in terms of electromagnetic shielding and thermal stability. The PDMS composites have great potential in the thermal management of electronic devices.

Effects of konjac glucomannan/pomegranate peel extract composite coating on the quality and nutritional properties of fresh-cut kiwifruit and green bell pepper.

The effects of an edible coating, based on konjac glucomannan (KG) incorporated with pomegranate peel extracts (PE), on the physicochemical and nutritional properties of fresh-cut kiwifruit and green bell pepper during storage were investigated. The optimal extract time (40.6 min), temperature (54.5 °C), and ultrasound power (255.5 W) with response surface method, provided a high total antioxidant activity (TAA) of (92.31 ± 1.43)%. Fresh-cut kiwifruit and green bell pepper were coated by dipping using five treatments (distilled water, ascorbic acid, KG, PE, KG + PE), packed into polymeric film and stored for 8 days at 10 °C. Distilled water treatment was used as control. KG + PE treatment resulted in the highest total soluble solid and titratable acidity in fresh-cut kiwifruit, while the maximum firmness in fresh-cut green bell pepper. The weight loss was both effectively decreased in samples treated with KG or KG + PE. All samples treated with KG + PE had significantly higher contents of chlorophyll, ascorbic acid, total phenolic and TAA than others. Moreover, the KG + PE group had the lowest counts of microorganisms in all samples. KG coating incorporated with PE was proved to be efficient in maintaining the physico-chemical and nutritional properties of fresh-cut kiwifruit and green bell pepper during low temperature storage compared with control. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05006-7.

Measuring Mechanism and Applications of Polymer-Based Flexible Sensors.

A new type of flexible sensor, which could maintain the deformation consistency and achieve the real-time detection of the variation in load of the measured object, was proposed in this work. According to the principle of forced assembly, PDMS was used as the substrate of sensitive components and electrodes, while carbon fiber was added as a conductive medium to prepare a polymer-based flexible sensor, which effectively overcame the deformation limitation and output instability of conventional flexible sensors due to different substrates of sensitive components and the electrode. Combined with the sensor structure and the forced assembly method, a theoretical analysis of its conductive measurement mechanism was carried out. Meanwhile, an experimental test device was designed to test and analyze the output characteristics of the flexible sensor under a static and dynamic alternating load. The results show that the flexible sensor exhibited linear output under the dynamic alternating load of 10 kN to 60 kN and frequency of 3 Hz. Peak and valley value had the same phase with the load extremes. The dynamic and static experiments show that the resistance output signal and the sensitivity was in the range of 310~624.15 Ω and 171⁻183 N/Ω respectively. However, due to the hysteresis of the elastic recovery of the polymer, the output repeatability of the flexible sensor under the dynamic alternating load was 5.03% and 0.78% lower than that of the static load, respectively. Combined with the static and dynamic experiments, it was verified that the polymer-based flexible sensor can maintain the same deformation characteristics with the measured object, and at the same time outputted a resistance signal with a certain mapping relationship with the applied load. The repeatability of the output signal under dynamic and static experiments was within ±7%, which can meet the measurement requirements of the fatigue life of the measured body during periodic load.

Phase-Controlled Synthesis of Nickel Phosphide Nanocrystals and Their Electrocatalytic Performance for the Hydrogen Evolution Reaction.

The phase of nanocrystals has a key role in the modulation of catalytic properties. Uniform and well-crystallized nickel phosphide nanocrystals with controlled phases (Ni5 P4 , Ni2 P, and Ni12 P5 ) and narrow size distributions are synthesized by a wet chemical method. The phases of the as-synthesized nickel phosphide nanocrystals are controlled by the P/Ni precursor molar ratio, heating process, and time of reaction. Rarely reported nearly monodisperse 5.6 nm Ni5 P4 nanocrystals are successfully synthesized and show superior hydrogen evolution reaction (HER) activity. Only a low overpotential of 103 mV is required to achieve the HER current of 10 mA cm-2 at a low catalyst loading of 0.12 mg cm-2 . The high HER activity is attributed to the high quality of the as-obtained Ni5 P4 nanocrystals, which have the electronic effect from the Ni5 P4 phase and also high surface area owing to the small particle size. A systematic study of the controlled synthesis of nickel phosphide nanocrystals is shown in this paper, and the HER catalytic activity is improved through the phase- and size-controlled synthesis of nanocrystals.

Highly stretchable and ultrathin nanopaper composites for epidermal strain sensors.

Multifunctional electronics are attracting great interest with the increasing demand and fast development of wearable electronic devices. Here, we describe an epidermal strain sensor based on an all-carbon conductive network made from multi-walled carbon nanotubes (MWCNTs) impregnated with poly(dimethyl siloxane) (PDMS) matrix through a vacuum filtration process. An ultrasonication treatment was performed to complete the penetration of PDMS resin in seconds. The entangled and overlapped MWCNT network largely enhances the electrical conductivity (1430 S m-1), uniformity (remaining stable on different layers), reliable sensing range (up to 80% strain), and cyclic stability of the strain sensor. The homogeneous dispersion of MWCNTs within the PDMS matrix leads to a strong interaction between the two phases and greatly improves the mechanical stability (ca. 160% strain at fracture). The flexible, reversible and ultrathin (<100 µm) film can be directly attached on human skin as epidermal strain sensors for high accuracy and real-time human motion detection.

Microfluidic-Based Single-Cell Study: Current Status and Future Perspective.

Investigation of cell behavior under different environments and manual operations can give information in specific cellular processes. Among all cell-based analysis, single-cell study occupies a peculiar position, while it can avoid the interaction effect within cell groups and provide more precise information. Microfluidic devices have played an increasingly important role in the field of single-cell study owing to their advantages: high efficiency, easy operation, and low cost. In this review, the applications of polymer-based microfluidics on cell manipulation, cell treatment, and cell analysis at single-cell level are detailed summarized. Moreover, three mainly types of manufacturing methods, i.e., replication, photodefining, and soft lithography methods for polymer-based microfluidics are also discussed.

Recent Progress in Metal-Based Nanoparticles Mediated Photodynamic Therapy.

Photodynamic therapy (PDT) is able to non-invasively treat and diagnose various cancers and nonmalignant diseases by combining light, oxygen, and photosensitizers (PSs). However, the application of PDT is hindered by poor water solubility and limited light-penetration depth of the currently available photosensitizers (PSs). Water solubility of PSs is crucial for designing pharmaceutical formulation and administration routes. Wavelength of light source at visible range normally has therapeutic depth less than 1 mm. In this review, focus is on the recent research progress of metal-based nanoparticles being applied in PDT. The potential toxicity of these nanoscales and future directions are further discussed.

The effect of budesonide-formoterol powder inhalation on cough and lung function following thoracoscopic pulmonary surgery: a retrospective cohort study.

OBJECTIVES: To explore whether portable budesonide-formoterol powder inhalation can ameliorate cough symptoms and improve pulmonary function recovery in patients who underwent thoracoscopic lung surgery. METHODS: Clinical data of patients who underwent thoracoscopic pulmonary resection at Henan Provincial People's Hospital between December 2022 and May 2023 were extracted. To evaluate the impact of continuous post-operative use of portable budesonide-formoterol powder inhalation, patients were divided into two groups: the control group and the case group. Next, we compared the Leicester cough score and pulmonary function indexes of the patients before surgery, one month and six month after the operation. RESULTS: A total of 188 cases were included, and the baseline demographic characteristics of both groups were well-balanced. The internal consistency of the LCQ-MC scale, as indicated by Cronbach's α coefficients, were all greater than 0.8, and there was no significant difference in LCQ-MC scores between the two groups before the operation (Z=-1.173, P=0.241). Postoperatively, the LCQ-MC score in the case group was significantly higher than that in the control group (18.66 vs. 16.79, P<0.01), with a notable statistically significant difference in the reduction of LCQ-MC scores between the two groups (1.32 vs. 3.30, P<0.01). Analysis of lung function revealed that patients in the case group exhibited significant improvements in FEV1/FVC, FVC, FEV1, PEF, MMEF75/25, MVV, DLCO and the RV/TLC indexes compared to the control group (P<0.01). CONCLUSIONS: Portable budesonide-formoterol powder inhalation can alleviate cough symptoms and promote pulmonary function recovery in patients following thoracoscopic lung surgery.

Enhancing Brain-Computer Interface Performance by Incorporating Brain-to-Brain Coupling.

Human cooperation relies on key features of social interaction in order to reach desirable outcomes. Similarly, human-robot interaction may benefit from integration with human-human interaction factors. In this paper, we aim to investigate brain-to-brain coupling during motor imagery (MI)-based brain-computer interface (BCI) training using eye-contact and hand-touch interaction. Twelve pairs of friends (experimental group) and 10 pairs of strangers (control group) were recruited for MI-based BCI tests concurrent with electroencephalography (EEG) hyperscanning. Event-related desynchronization (ERD) was estimated to measure cortical activation, and interbrain functional connectivity was assessed using multilevel statistical analysis. Furthermore, we compared BCI classification performance under different social interaction conditions. In the experimental group, greater ERD was found around the contralateral sensorimotor cortex under social interaction conditions compared with MI without any social interaction. Notably, EEG channels with decreased power were mainly distributed around the frontal, central, and occipital regions. A significant increase in interbrain coupling was also found under social interaction conditions. BCI decoding accuracies were significantly improved in the eye contact condition and eye and hand contact condition compared with the no-interaction condition. However, for the strangers' group, no positive effects were observed in comparisons of cortical activations between interaction and no-interaction conditions. These findings indicate that social interaction can improve the neural synchronization between familiar partners with enhanced brain activations and brain-to-brain coupling. This study may provide a novel method for enhancing MI-based BCI performance in conjunction with neural synchronization between users.

Multiscale Canonical Coherence for Functional Corticomuscular Coupling Analysis.

Functional corticomuscular coupling (FCMC) probes multi-level information communication in the sensorimotor system. The canonical Coherence (caCOH) method has been leveraged to measure the FCMC between two multivariate signals within the single scale. In this paper, we propose the concept of multiscale canonical Coherence (MS-caCOH) to disentangle complex multi-layer information and extract coupling features in multivariate spaces from multiple scales. Then, we verified the reliability and effectiveness of MS-caCOH on two types of data sets, i.e., a synthetic multivariate data set and a real-world multivariate data set. Our simulation results showed that compared with caCOH, MS-caCOH enhanced coupling detection and achieved lower pattern recovery errors at multiple frequency scales. Further analysis on experimental data demonstrated that the proposed MS-caCOH method could also capture detailed multiscale spatial-frequency characteristics. This study leverages the multiscale analysis framework and multivariate method to give a new insight into corticomuscular coupling analysis.

[Preparation and evaluation of chitosan-based light source-loaded soluble microneedles].

The combination of photodynamic therapy and drug delivery microneedle (MN) provides a safe and effective way to treat tumors. In this paper, we designed a controlled and sustained-release drug-loaded microneedle patch (LED-losartan-HEMA/CS-MN, LLH-CSMN) based on chitosan loaded with high-energy photons, investigated its preparation process, and characterized the morphology and size of the microneedle array with losartan as the model drug. The mechanical properties of LLH-CSMN, skin puncture properties, slow release properties and the photothermal properties of high energy photons under long-term operation were investigated. The experimental results showed that the chitosan-based microneedle patch loaded with high-energy photons can effectively open channels on the skin surface for drug delivery and photodynamic therapy. At the same time, the in vitro percutaneous diffusion experiment showed that the microneedles prepared with losartan as the model drug released about 30% of the drug within 1 h, about 60% of the drug in total within 1 d, followed by slow release, and finally released 93% of the drug after 6 d. LLH-CSMN has controllable slow-release characteristics and good long-term photoassisted therapy effect. It provides a new safe and effective way for tumor treatment.

Explainable Deep-Learning Prediction for Brain-Computer Interfaces Supported Lower Extremity Motor Gains Based on Multistate Fusion.

Predicting the potential for recovery of motor function in stroke patients who undergo specific rehabilitation treatments is an important and major challenge. Recently, electroencephalography (EEG) has shown potential in helping to determine the relationship between cortical neural activity and motor recovery. EEG recorded in different states could more accurately predict motor recovery than single-state recordings. Here, we design a multi-state (combining eyes closed, EC, and eyes open, EO) fusion neural network for predicting the motor recovery of patients with stroke after EEG-brain-computer-interface (BCI) rehabilitation training and use an explainable deep learning method to identify the most important features of EEG power spectral density and functional connectivity contributing to prediction. The prediction accuracy of the multi-states fusion network was 82%, significantly improved compared with a single-state model. The neural network explanation result demonstrated the important region and frequency oscillation bands. Specifically, in those two states, power spectral density and functional connectivity were shown as the regions and bands related to motor recovery in frontal, central, and occipital. Moreover, the motor recovery relation in bands, the power spectrum density shows the bands at delta and alpha bands. The functional connectivity shows the delta, theta, and alpha bands in the EC state; delta, theta, and beta mid at the EO state are related to motor recovery. Multi-state fusion neural networks, which combine multiple states of EEG signals into a single network, can increase the accuracy of predicting motor recovery after BCI training, and reveal the underlying mechanisms of motor recovery in brain activity.

Enhancement of EEG-EMG coupling detection using corticomuscular coherence with spatial-temporal optimization.

Objective. Corticomuscular coherence (CMC) is widely used to detect and quantify the coupling between motor cortex and effector muscles. It is promisingly used in human-machine interaction (HMI) supported rehabilitation training to promote the closed-loop motor control for stroke patients. However, suffering from weak coherence features and low accuracy in contingent neurofeedback, its application to HMI rehabilitation robots is currently limited. In this paper, we propose the concept of spatial-temporal CMC (STCMC), which is the coherence by refining CMC with delay compensation and spatial optimization.Approach. The proposed STCMC method measures the coherence between electroencephalogram (EEG) and electromyogram (EMG) in the multivariate spaces. Specifically, we combined delay compensation and spatial optimization to maximize the absolute value of the coherence. Then, we tested the reliability and effectiveness of STCMC on neurophysiological data of force tracking tasks.Main results. Compared with CMC, STCMC not only enhanced the coherence significantly between brain and muscle signals, but also produced higher classification accuracy. Further analysis showed that temporal and spatial parameters estimated by the STCMC reflected more detailed brain topographical patterns, which emphasized the different roles between the contralateral and ipsilateral hemisphere.Significance. This study integrates delay compensation and spatial optimization to give a new perspective for corticomuscular coupling analysis. It is also feasible to design robotic neurorehabilitation paradigms by the proposed method.

Treatment of atrazine-containing wastewater by algae-bacteria consortia: Signal transmission and metabolic mechanism.

Atrazine is a toxic endocrine disruptor. Biological treatment methods are considered to be effective. In the present study, a modified version of the algae-bacteria consortia (ABC) was established and a control was simultaneously set up to investigate the synergistic relationship between bacteria and algae and the mechanism by which atrazine is metabolized by those microorganisms. The total nitrogen (TN) removal efficiency of the ABC reached 89.24% and the atrazine concentration was reduced to below the level recommended by the Environment Protection Agency (EPA) regulatory standards within 25 days. The protein signal released from the extracellular polymeric substances (EPS) secreted by the microorganisms triggered the resistance mechanism of the algae, and the conversion of humic acid to fulvic acid and electron transfer constituted the synergistic mechanism between the bacteria and algae. The mechanism by which atrazine is metabolized by the ABC mainly consists of hydrogen bonding, H-pi interactions, and cation exchange with atzA for hydrolysis, followed by a reaction with atzC for decomposition to non-toxic cyanuric acid. Proteobacteria was the dominant phylum for bacterial community evolution under atrazine stress, and the analysis revealed that the removal of atrazine within the ABC was mainly dependent on the proportion of Proteobacteria and the expression of degradation genes (p < 0.01). EPS played a major role in the removal of atrazine within the single bacteria group (p < 0.01).

Spatiotemporal evolution of dissolved organic matter (DOM) and its response to environmental factors and human activities.

The South-to-North Water Diversion East Project (SNWDP-E) is an effective way to realize the optimal allocation of water resources in China. The North Dasha River (NDR) is the reverse recharge section that receives water from the Yufu River to the Wohushan Reservoir transfer project line in the SNWDP. However, the dissolved organic matter (DOM) evolution mechanism of seasonal water transfer projects on tributary waters has not been fully elucidated. In this paper, the NDR is the main object, and the changes in the composition and distribution of spectral characteristics during the winter water transfer period (WT) as well as during the summer non-water transfer period (NWT) are investigated by parallel factor analysis (PARAFAC). The results showed that the water connectivity caused by water transfer reduces the environmental heterogeneity of waters in the basin, as evidenced by the ammonia nitrogen (NH4+-N) and total phosphorus (TP) in the water body were significantly lower (p<0.05, p<0.01) during the water transfer period than the non-water transfer period. In addition, the fluorescence intensity of DOM was significantly lower in the WT than the NWT (p<0.05) and was mainly composed of humic substances generated from endogenous sources with high stability. While the NWT was disturbed by anthropogenic activities leading to significant differences in DOM composition in different functional areas. Based on the redundancy analysis (RDA) and multiple regression analysis, it was found that the evolution of the protein-like components is dominated by chemical oxygen demand (COD) and NH4+-N factors during the WT. While the NWT is mainly dominated by total nitrogen (TN) and TP factors for the evolution of the humic-like components. This study helps to elucidate the impact of water transfer projects on the trunk basin and contribute to the regulation and management of inter-basin water transfer projects.

Water Availability, Soil Characteristics, and Confounding Effects on the Patterns of Biocrust Diversity in the Desert Regions of Northern China.

The species diversity of biocrusts is an important community characteristic in determining their multiple ecosystem functions. Hence, understanding the diversity patterns of biocrusts and their environmental drivers is of fundamental importance. However, explain variables often correlated with each other; thus, the confounding effects among them may arise and result in spurious causal relationships and biased ecological inferences. In this study, we investigated the richness of three biocrust-forming components (mosses, lichens, and cyanobacteria-algae) and their environmental variables across six desert regions of northern China. A comparison between conventional redundancy analysis (RDA) and structural equation model (SEM) was conducted to study the environmental driver-richness relationship and the confounding effects. Our results showed that three latent variables related to water availability, soil texture, and soil salinity and sodicity, could account for the main environmental variations and explain the diversity patterns of biocrusts at the intracontinental scale. Water availability was positively and negatively related to the richness of mosses and cyanobacteria-algae, respectively, while soil texture was positively related to the richness of lichens. In addition, environmental variables confounded with each other caused distinct driver-richness relationships between results of RDA and SEM. Therefore, we suggest that future multivariable studies should utilize path analysis in conjunction with conventional canonical ordination to facilitate more rigorous ecological inferences.

[Preparation and transdermal effect of a tip-loaded bubble-soluble microneedle].

As a new transdermal drug delivery technology, bubble microneedle could achieve painless and precise drug delivery, which has attracted great attention from researchers. In order to improve the utilization rate of the drug carried by microneedle, we proposed a method for preparing a tip-loaded bubble-soluble microneedle. During the molding process of the microneedle, air bubbles were formed in the needle body, and the drug was concentrated on the needle tip. The preparation process of the bubble microneedle was optimized. The effects of foaming agent concentration, drying temperature, and solution viscosity on the forming of bubble microneedles were explored. Furthermore, the transdermal effect of the product was analyzed. The experimental results showed that the bubble microneedle forming process was stable, with the forming rate above 90% and the forming cycle shortened to about 4 h. The drug was mainly concentrated on the tip of the microneedle, with a length of 180 µm, and the length of the bubble was 250 µm. Moreover, the microneedle array can create microchannels on the mouse skin, and the needle bodies can be rapidly dissolved within 5 min. The bubble microneedle could rapidly release about 48% of the drug within 1 min and about 91% of the drug within 5 min. The bubble microstructure of the microneedle array hindered the diffusion of the drug to the substrate, which improves the utilization rate of the drug. This study provides a technical basis for the practical application of microneedle for transdermal drug delivery.