Joint Effect of Short-Term Exposure to Fine Particulate Matter and Ozone on Mortality: A Time Series Study in 272 Chinese Cities.

Short-term exposure to PM2.5 or O3 can increase mortality risk; however, limited studies have evaluated their interaction. A multicity time series study was conducted to investigate the synergistic effect of PM2.5 and O3 on mortality in China, using mortality data and high-resolution pollutant predictions from 272 cities in 2013-2015. Generalized additive models were applied to estimate associations of PM2.5 and O3 with mortality. Modification and interaction effects were explored by stratified analyses and synergistic indexes. Deaths attributable to PM2.5 and O3 were evaluated with or without modification of the other pollutant. The risk of total nonaccidental mortality increased by 0.70% for each 10 µg/m3 increase in PM2.5 when O3 levels were high, compared to 0.12% at low O3 levels. The effect of O3 on total nonaccidental mortality at high PM2.5 levels (1.26%) was also significantly higher than that at low PM2.5 levels (0.59%). Similar patterns were observed for cardiovascular or respiratory diseases. The relative excess risk of interaction and synergy index of PM2.5 and O3 on nonaccidental mortality were 0.69% and 1.31 with statistical significance, respectively. Nonaccidental deaths attributable to short-term exposure of PM2.5 or O3 when considering modification of the other pollutant were 28% and 31% higher than those without considering modification, respectively. Our results found synergistic effects of short-term coexposure to PM2.5 and O3 on mortality and suggested underestimations of attributable risks without considering their synergistic effects.

Research on Multiple-AUVs Collaborative Detection and Surrounding Attack Simulation.

Due to limitations in operational scope and efficiency, a single Autonomous Underwater Vehicle (AUV) falls short of meeting the demands of the contemporary marine working environment. Consequently, there is a growing interest in the coordination of multiple AUVs. To address the requirements of coordinated missions, this paper proposes a comprehensive solution for the coordinated development of multi-AUV formations, encompassing long-range ferrying, coordinated detection, and surrounding attack. In the initial phase, detection devices are deactivated, employing a path planning method based on the Rapidly Exploring Random Tree (RRT) algorithm to ensure collision-free AUV movement. During the coordinated detection phase, an artificial potential field method is applied to maintain AUV formation integrity and avoid obstacles, dynamically updating environmental probability based on formation movement. In the coordinated surroundings attack stage, predictive capabilities are enhanced using Long Short-Term Memory (LSTM) networks and reinforcement learning. Specifically, LSTM forecasts the target's position, while the Deep Deterministic Policy Gradient (DDPG) method controls AUV formation. The effectiveness of this coordinated solution is validated through an integrated simulation trajectory.

The Effect of Different Diameters of Fat Converters on Adipose Tissue and Its Cellular Components: Selection for Preparation of Nanofat.

BACKGROUND: Nanofat is an autologous product prepared mechanically from harvested fat. In nanofat grafting, converters are employed for mechanical emulsification to facilitate fat injection. To date, the study of different converters has received scant attention regarding whether they affect the characteristics of nanofat in terms of the practical applications and indications. OBJECTIVES: The authors set out to investigate the influence of different internal diameters of converters on biological functionality of nanofat during shuffling. METHODS: The 3-dimensional finite element method was employed to simulate the process of mechanical emulsification of fat and to research the stress with 5 different converters (3.76 mm, 2.00 mm, 1.20 mm, 1.00 mm, 0.80 mm). An assessment of the morphology of emulsified fat was conducted. Isolated stromal vascular fraction (SVF) was analyzed for cellular components, number, and viability through flowcytometry and live/ dead staining. Adipocytic and angiogenic differentiation assay allowed assessment of differentiation capacity of the SVF. RESULTS: The smaller the aperture of the converter, the greater the mechanical force on adipose tissue during mechanical emulsification, showing the different macroscopic and microscopic structure of the emulsified fat. No difference in viability or ratio of endothelial progenitor cells and other cells was found. Angiogenic and adipogenic differentiation capacity of the SVF significantly changed in 5 different converters. CONCLUSIONS: The mechanical emulsification from different apertures of converters exerts different effects of adipose tissue structure, cell content, and multipotency differentiation but not its viability. Converters with different apertures can be selected according to clinical needs.

Wnt5a regulates the cell proliferation and adipogenesis via MAPK-independent pathway in early stage of obesity.

The early stage of obesity is an important stage in the development of obesity. However, there are few studies which explored the property or changes in obesity at early stage especially involving Wnt5a. The associated gene expression of Wnt5a on cell regeneration and the effect of Wnt5a on rat adipose-derived stem cell (rASC) proliferation and adipogenesis need additional study. Here, we investigated the changes in obesity at early stage and how Wnt5a regulates rASC regeneration, proliferation, and adipogenesis. Our data revealed that obesity at early stage measured by Lee index presented a state with impaired adipogenesis and more infiltrated inflammatory cells but without significant changes in adipocyte sizes and inflammatory factors. The process might be associated with anti-canonical Wnt pathway and a reciprocal Wnt5a/JNK pathway. Besides the gene expression of Wnt5a decreased from cell passage 1 to passage 3. The cell proliferation was regulated by increasing dose of Wnt5a with the maximal effect at 50 ng/mL and 50 ng/mL Wnt5a suppressed adipogenic differentiation at middle-late stage of adipogenesis via anti-ß-catenin and a mitogen-activated protein kinase (MAPK) signaling-independent manner. Accordingly, the research helps to gain further insights into the early stage of obesity and its associated changes on a cellular and molecular level.

Concentrated Growth Factor Enhanced Fat Graft Survival: A Comparative Study.

BACKGROUND: Concentrated growth factors (CGFs) belong to a new generation biomaterials that concentrate large number of growth factors and CD34 stem cells in small volume of plasma. OBJECTIVE: The purpose of this study was to evaluate the impact of the new technique, CGF, on fat graft survival, which compared with platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). MATERIALS AND METHODS: Nude mice received fat graft were divided into PRP group, PRF group, CGF group, and saline. The grafts were volumetrically and histologically evaluated at 4, 8, and 12 weeks after fat grafting. In vitro growth factor levels in PRP, PRF, and CGF were compared using enzyme-linked immunoassay method. Cell count and real-time polymerase chain reaction were used to evaluate the impact of CGF in medium on human adipose-derived stem cell (hADSC) proliferation and vascular differentiation, respectively. RESULTS: Fat graft weight was significantly higher in the CGF group than those in the other groups, and histologic evaluation revealed greater vascularity, fewer cysts, and less fibrosis. Adding CGF to the medium maximally promoted hADSC proliferation and expressing vascular endothelial growth factor and PECAM-1. CONCLUSION: In this preliminary study, CGF treatment improved the survival and quality of fat grafts.

Trading strategies of energy storage participation in day-ahead joint market based on Stackelberg game.

The goal of "carbon peak, carbon neutral" and the increasing expansion of new energy have helped to advance the development of energy storage. However, since the operating cost of energy storage is high, carbon emission trading and power market trading have emerged, effectively improving the efficiency. In this paper, a trading strategy and bidding framework of energy storage participation in the day-ahead joint market are studied. A market bidding model has been established in a framework based on the Stackelberg game. Finally, the "Day-Ahead and Intra-Day and Carbon Emission Trading (CET)" market clearing model has been constructed. It has been simplified to solve the equivalent mixed-integer linear programming (MILP) problem with equilibrium constraints through the use of the Karush-Kuhn-Tucker (KKT) optimality criterion and duality principle. The proposed model is validated through improved examples to obtain thermal unit output cuts of up to 32.2% during load trough periods, and up to 16.75% increase in clearing prices during peak load periods. The storage life is extended and the storage output variation is minimized.

Association of exposure to ultraviolet radiation and warm-season ozone air pollution with incident age-related macular degeneration: A nationwide cohort study in China.

BACKGROUND: As the leading cause of blindness, age-related macular degeneration (AMD) performs an adverse impact on human health and disability. AMD have been reported to be associated with environmental factors; however, the association between ultraviolet (UV) radiation, warm-season ambient ozone pollution, and incident AMD remains unclear. METHODS: In this study, 19,707 participants without AMD at baseline were included from a nationwide longitudinal cohort in China. UV radiation and warm-season ozone exposure were evaluated through satellite-based models. Incident AMD was diagnosed via ophthalmological fundus images. Cox proportional hazard regression models were employed to explore the association of UV radiation and warm-season ozone with incident AMD, and the hazard ratios (HRs) and 95 % confidence intervals (CIs) were reported. RESULTS: During 312,935 person-month of follow-up, 3774 participants developed to AMD. High exposure to both UV radiation and warm-season ozone was associated with increasing risk of incident AMD, with HRs and 95 % CIs of 1.32 (1.23, 1.41) and 1.20 (1.11, 1.29) in two-exposure models, respectively. Moreover, negative interaction between UV radiation and warm-season ozone was identified, and it was found that exposure to high UV radiation and low ozone presented the highest hazard for AMD. Subgroup analyses showed that the UV-AMD association was stronger in southern China, while the ozone-AMD association was greater in northern China and rural areas. CONCLUSION: Our study provides the first epidemiological evidence that both UV radiation and warm-season ozone would elevate the risk of incident AMD, and the hazard of higher UV radiation may be attenuated by exposure to ozone. Strategies for decreasing AMD burden should jointly consider environmental exposures and geographic locations.

The protective effects of repetitive transcranial magnetic stimulation with different high frequencies on motor functions in MPTP/probenecid induced Parkinsonism mouse models.

BACKGROUND: High-frequency repeated transcranial magnetic stimulation (rTMS) stimulating the primary motor cortex (M1) is an alternative, adjunctive therapy for improving the motor symptoms of Parkinson's disease (PD). However, whether the high frequency of rTMS positively correlates to the improvement of motor symptoms of PD is still undecided. By controlling for other parameters, a disease animal model may be useful to compare the neuroprotective effects of different high frequencies of rTMS. OBJECTIVE: The current exploratory study was designed to compare the protective effects of four common high frequencies of rTMS (5, 10, 15, and 20 Hz) and iTBS (a special form of high-frequency rTMS) and explore the optimal high-frequency rTMS on an animal PD model. METHODS: Following high frequencies of rTMS application (twice a week for 5 weeks) in a MPTP/probenecid-induced chronic PD model, the effects of the five protocols on motor behavior as well as dopaminergic neuron degeneration levels were identified. The underlying molecular mechanisms were further explored. RESULTS: We found that all the high frequencies of rTMS had protective effects on the motor functions of PD models to varying degrees. Among them, the 10, 15, and 20 Hz rTMS interventions induced comparable preservation of motor function through the protection of nigrostriatal dopamine neurons. The enhancement of brain-derived neurotrophic factor (BDNF), dopamine transporter (DAT), and vesicular monoamine transporter 2 (VMAT-2) and the suppression of TNF-α and IL-1ß in the nigrostriatum were involved in the process. The efficacy of iTBS was inferior to that of the above three protocols. The effect of 5 Hz rTMS protocol was weakest. CONCLUSIONS: Combined with the results of the present study and the possible side effects induced by rTMS, we concluded that 10 Hz might be the optimal stimulation frequency for preserving the motor functions of PD models using rTMS treatment.

The Effect of Long-Term Passage on Porcine SMCs' Function and the Improvement of TGF-ß1 on Porcine SMCs' Secretory Function in Late Passage.

Cultured meat is one of the meat substitutes produced through tissue engineering and other technologies. Large-scale cell culture is the key for cultured meat products to enter the market. Therefore, this study is aimed to explore the effect of long-term passage in vitro on smooth muscle cells (SMCs) and the effect of transforming growth factor-ß1 (TGF-ß1) on SMCs in the late passage. Multiple passages lead to the decline of the proliferation rate of SMCs in the proliferation stage and the differentiation ability in the differentiation stage. Transcriptome results showed that the ECM pathway and aging-related signaling pathways were significantly up-regulated in the late passage period. TGF-ß1 did not promote SMCs of late passage proliferation at the proliferation stage but promoted the gene and protein expression of collagen as the main protein of the extracellular matrix proteins at the differentiation stage. In addition, proteomic analysis revealed that TGF-ß1 promoted the expression of cell adhesion molecules which activate the Hippo signaling pathway and the HIF-1 signaling pathway and further promoted the production of collagen-containing extracellular matrix proteins. This could provide ideas for large-scale production of cultured meat products using SMCs.

Toward Enhanced Aerosol Particle Adsorption in Never-Bursting Bubble via Acoustic Levitation and Controlled Liquid Compensation.

Bubbles in air are ephemeral because of gravity-induced drainage and liquid evaporation, which severely limits their applications, especially as intriguing bio/chemical reactors. In this work, a new approach using acoustic levitation combined with controlled liquid compensation to stabilize bubbles is proposed. Due to the suppression of drainage by sound field and prevention of capillary waves by liquid compensation, the bubbles can remain stable and intact permanently. It has been found that the acoustically levitated bubble shows a significantly enhanced particle adsorption ability because of the oscillation of the bubble and the presence of internal acoustic streaming. The results shed light on the development of novel air-purification techniques without consuming any solid filters.

Liuwei Dihuang Decoction Drug-containing Serum Attenuates Transforming Growth Factor-ß1-induced Epithelial-mesenchymal Transition in HK-2 Cells by Inhibiting NF-κB/Snail Signaling Pathway.

OBJECTIVES: The nuclear factor-κB (NF-κB) signaling pathway plays an important role in regulating tubular epithelial-mesenchymal transition (EMT), an indispensable cellular programme for driving organ fibrosis and tumor progression. Liuwei Dihuang Decoction (LWD) is an effective Chinese formula for treating chronic renal failure. METHODS: First, by using morphological examination, immunofluorescence staining assay, RTqPCR, and Western blot analysis, in vitro experiments were designed to analyze NF-κB and EMT markers (including Snail, α-SMA, and E-cadherin) in transforming growth factor-ß1 (TGF-ß1) induced renal tubular epithelial cells (HK-2) and to detect the expression levels of LWD-CS cotreatment. Then, the recombinant lentiviral vector was overexpressed and knocked down by NF- κB and transfected into HK-2 cells. Cells were treated with TGF-ß1 (10 ng/ml) with blank serum or LWD-containing serum, respectively, and the expression of these molecules in the NF-κB/Snail signaling pathway was further evaluated. RESULTS: Our results confirmed that TGF-ß1 could induce EMT, nuclear translocation of NF-κB p65, and activate the NF-κB/Snail signaling pathway in HK-2 cells. Furthermore, NF-κB knocked-down dramatically increases the TGF-ß1-induced mRNA and protein expression level of E-cadherin and reduces the level of Snail and α-SMA; this is reversed by NF-κB overexpression. LWD can decrease the EMT levels through the NF-κB/Snail signaling activation in TGF-ß1-induced EMT of HK-2 cells. CONCLUSION: The present study provides evidence suggesting a novel mechanism that LWD exerts anti-fibrosis effects through inhibiting activation of the NF-κB/Snail signaling pathway and consequently downregulating the TGF-ß1-induced EMT in renal tubular epithelial cells.

Hydrogen bond donor functionalized poly(ionic liquids)@MIL-101 for the CO2 capture and improving the catalytic CO2 conversion with epoxide.

Hydrogen bond donor functionalized poly(ionic liquids) were incorporated into MIL-101 framework for synthesis of composites PIL-R@MIL-101 (R = COOH, OH, NH2). The effect of different hydrogen bond donors on CO2-epoxide cycloaddition reaction was discussed through XPS, NH3-TPD characterizations. Thereinto, PIL-COOH@MIL-101 showed efficient catalytic performance in the cycloaddition reaction of CO2 and epichlorohydrin, 92.7% substrate conversion was obtained under 70 °C, 1.0 MPa, cocatalyst- and solvent-free conditions for 2.5 h. The improved activity was benefited from the synergistic effects of Lewis acidic Cr centers, carboxyl group, and nucleophilic Br-, together with the high surface area (1178 m2/g), and good CO2 affinity. In addition, PIL-COOH@MIL-101 also showed facile recovery method by easy centrifugation and good recycling stability. Considering the good CO2 affinity, excellent catalytic performance in CO2 cycloaddition reaction, better thermal and recycling stabilities, the facilely prepared functionalized poly(ionic liquid)@MIL-101 composite would exhibit promising application prospect in CO2 capture and conversion.

Research on the innovation of time-honored brands from the perspective of dual ethical patterns.

Introduction: Innovation has become an important means to promote the high-quality development of time-honored brands. However, the research on how to stimulate innovation investment in time-honored brands, especially that conducted in the local context, is still rare. To supplement the research limitations, this study adopts the perspective of dual ethical patterns and is set in the domestic context to explore the ethical influence of traditional cultures and marketization on the innovation investment of time-honored brands. Methods: We proposed two complementary methods, which are OLS regression and fsQCA analysis respectively, to systematically analyze the mechanism and key path of the dual ethical pattern to promote the innovation of time-honored brands. Results: The results show that traditional culture and marketization level are both positively related to the innovation of time-honored brands. However, traditional culture and marketization level are mutually exclusive in their process of affecting the innovation of time-honored brands. Discussion: This paper advances time-honored brands literature by highlighting the dual ethic pattern formed by traditional culture and marketization level on the innovation investment of time-honored brands. The findings respond to the academic debate between traditional culture and the innovation of time-honored brands, while enriching the research scope on the innovation mechanism of time-honored brands in the local context.

Basic research investment, innovation capability improvement, and economic growth efficiency.

This study explores the relationship between the proportion of basic research investment in R&D expenditure and regional economic growth efficiency and its influence path. A panel of data from 31 China's provincial was analysed by the fixed-effects model over 2009 to 2019. Empirical results highlight that: (1) the increase in the proportion of basic research investment has a significant promoting effect on regional economic growth efficiency, but it presents an "inverted U-shaped" impact path. Meanwhile, the threshold effect model test results reveal that basic research investment plays a more significant role in promotion when the per capita income level exceeds a certain threshold. (2) The test results of the mediating effect model indicate that the improvement of the level of human capital is the intermediate channel through which the investment in basic research affects regional economic growth efficiency, while the mediating effect of the increase of knowledge storage on the process of the investment in basic research affecting regional economic growth efficiency is not supported by data. Potential policy measures are discussed.

Treatment effect analysis of curettage for jaw cysts based on volumetric assessment and image registration.

The study was conducted to develop a visual and intuitive quantitative evaluation method for maxillary cystic lesions after curettage. Mimics 16.0 and Geomagic Studio 2013 were used to form a precise reconstruction of the cystic lesion morphology of 60 cases; the average reduction rates and 95% confidence interval were calculated. Computed tomography (CT) registration was performed before and after surgery to observe morphology features of the bone regeneration of the cystic area. The average reduction rates (RR) of the cysts after curettage were (43.56 ± 16.79)%, (54.33 ± 17.15)% and (68.53 ± 15.99)% at 3 months, 6 months and 12 months after surgery, respectively. The average monthly reduction rates (MRR) were (12.07 ± 4.35)%, (8.16 ± 2.84)% and (5.35 ± 1.52)% at 3 months, 6 months and 12 months after surgery, respectively. Correlation analysis by comparing with each group showed that the effect of sex and age in the 3-month group and the initial size in the 12-month group on RR and MRR were statistically significant. Within the limitations of the study it seems that the chosen approach for quantitative evaluation of the therapeutic effect of curettage for jaw cystic lesions might facilitate visual and quantitative follow-up of cyst curettage and timely detection of recurrence.

YAP Promotes Cell Proliferation and Stemness Maintenance of Porcine Muscle Stem Cells under High-Density Condition.

Muscle stem cells (MuSCs) isolated ex vivo are essential original cells to produce cultured meat. Currently, one of the main obstacles for cultured meat production derives from the limited capacity of large-scale amplification of MuSCs, especially under high-density culture condition. Here, we show that at higher cell densities, proliferation and differentiation capacities of porcine MuSCs are impaired. We investigate the roles of Hippo-YAP signaling, which is important regulators in response to cell contact inhibition. Interestingly, abundant but not functional YAP proteins are accumulated in MuSCs seeded at high density. When treated with lysophosphatidic acid (LPA), the activator of YAP, porcine MuSCs exhibit increased proliferation and elevated differentiation potential compared with control cells. Moreover, constitutively active YAP with deactivated phosphorylation sites, but not intact YAP, promotes cell proliferation and stemness maintenance of MuSCs. Together, we reveal a potential molecular target that enables massive MuSCs expansion for large-scale cultured meat production under high-density condition.

Copper Tolerance Mediated by FgAceA and FgCrpA in Fusarium graminearum.

All organisms must secure essential trace elements (e.g., Cu) for survival and reproduction. However, excess trace element accumulation in cells is highly toxic. The maintenance of copper (Cu) homeostasis has been extensively studied in mammals, bacteria, and yeast but not in plant pathogens. In this study, we investigated the molecular mechanisms of copper tolerance in Fusarium graminearum, the important wheat head scab fungus. RNA-seq revealed induced expression of the P-type ATPase transporter FgCrpA and metallothionein (MT) FgCrdA after excess Cu treatment. Deletion of FgCrpA but not FgCrdA resulted in reduced tolerance to Cu toxicity. The "Cu fist" transcription factor FgAceA was involved in Cu detoxification through activation of FgCrpA. △FgAceA was more sensitive to copper toxicity than △FgCrpA and overexpression of FgCrpA restored copper tolerance in △FgAceA. FgAceA negatively regulated aurofusarin production and its biosynthetic gene expression. △FgCrpA and △FgAceA were reduced in virulence in flowering wheat heads and synthesized decreased amounts of the mycotoxin deoxynivalenol when challenged with excess Cu. Taken together, these results suggest that mediation of Cu tolerance in F. graminearum mainly relies on the Cu efflux pump and that FgAceA governs Cu detoxification through activation of FgCrpA.

FgIlv3a is crucial in branched-chain amino acid biosynthesis, vegetative differentiation, and virulence in Fusarium graminearum.

Dihydroxyacid dehydratase (DHAD), encoded by ILV3, catalyses the third step in the biosynthetic pathway of branched-chain amino acids (BCAAs), which include isoleucine (Ile), leucine (Leu), and valine (Val). Enzymes involved in BCAA biosynthesis exist in bacteria, plants, and fungi but not in mammals and are therefore attractive targets for antimicrobial or herbicide development. In this study, three paralogous ILV3 genes (FgILV3A, FgILV3B, and FgILV3C) were identified in the genome of Fusarium graminearum, the causal agent of Fusarium head blight (FHB). Deletion of FgILV3A alone or combined with FgILV3B or FgILV3C indicated an important role for FgILV3A in BCAA biosynthesis. FgILV3A deletion mutants lost the ability to grow on medium lacking amino acids. Exogenous supplementation of 1 mM Ile and Val rescued the auxotrophy of ΔFgIlv3A, though 5 mM was required to recover the growth defects in ΔFgIlv3AB and ΔFgIlv3AC strains, indicating that FgIlv3b and FgIlv3c exhibit redundant but accessory roles with FgIlv3a in BCAA biosynthesis. The auxotrophy of ΔFgIlv3A resulted in pleiotropic defects in aerial hyphal growth, in conidial formation and germination, and in aurofusarin accumulation. In addition, the mutants showed reduced virulence and deoxynivalenol production. Overall, our study demonstrates that FgIlv3a is crucial for BCAA biosynthesis in F. graminearum and a candidate fungicide target for FHB management.

SecureLR: Secure Logistic Regression Model via a Hybrid Cryptographic Protocol.

Machine learning applications are intensively utilized in various science fields, and increasingly the biomedical and healthcare sector. Applying predictive modeling to biomedical data introduces privacy and security concerns requiring additional protection to prevent accidental disclosure or leakage of sensitive patient information. Significant advancements in secure computing methods have emerged in recent years, however, many of which require substantial computational and/or communication overheads, which might hinder their adoption in biomedical applications. In this work, we propose SecureLR, a novel framework allowing researchers to leverage both the computational and storage capacity of Public Cloud Servers to conduct learning and predictions on biomedical data without compromising data security or efficiency. Our model builds upon homomorphic encryption methodologies with hardware-based security reinforcement through Software Guard Extensions (SGX), and our implementation demonstrates a practical hybrid cryptographic solution to address important concerns in conducting machine learning with public clouds.

Comparison of the Microstructures and Properties of Different Microcannulas for Hyaluronic Acid Injection.

BACKGROUND: Microcannulas are used for hyaluronic acid and other filler injections and reduce the side effects and complications. There are several microcannulas and the differences between microcannulas have not been carefully investigated. The purpose of this study was to compare the microstructures and properties of different microcannulas by several trials and provide guidance for clinical application. METHODS: Nine types of microcannulas from different manufacturers were chosen. Scanning electron microscopy was used to obtain high-definition images of microstructures, chemical composition analyzers were used to test the chemical composition of the tips, and a universal testing machine was used to measure mechanical properties. The injection speed test recorded the time spent for the weight to push hyaluronic acid out of microcannulas. The vessel piercing force test was conducted to simulate the process of puncturing the vessels in vitro. RESULTS: The scanning electron microscopic images showed the tip shapes and inner surfaces that may relate to the characteristics. The chemical composition of most microcannulas met the American Society for Testing and Materials standards basically. The mechanical properties were obviously different. The results of the injection speed test were discrepant more than seven times. The vessel piercing test showed which microcannula was the most difficult and easiest to puncture the aorta. CONCLUSIONS: The results indicated that there are significant differences between different microcannulas. The differences are instructive to physicians for selecting suitable microcannulas to improve the injection effect and reduce discomfort and complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.