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Abstract Background Coronary artery bypass grafting (CABG) is often performed with hypothermic cardiopulmonary bypass (CPB) to reduce metabolic demands and protect the myocardium. However, hypothermia can increase bleeding risks and other complications. Methods This is a prospective, multi-center, randomized controlled trial. From September 2023 to December 2024, a total of 336 eligible patients planning to undergo on-pump CABG will be enrolled. All participants will be randomly divided into mild hypothermia CPB group (target oxygenator arterial outlet blood temperature at 32–33℃) or normothermia CPB group (target oxygenator arterial outlet blood temperature at 35–36℃). The primary endpoint is Universal Definition of Perioperative Bleeding (UDPB) class 2–4. Secondary endpoints are class of UDPB, levels of coagulation and inflammatory factors, in-hospital mortality, perioperative related complications, ICU length of stay, and hospital length of stay. Discussion This clinical trial aims to compare the effects of different target temperature during CPB on postoperative bleeding and to explore optimal temperature strategy to provide new clinical evidence. Trial registration Chictr.org.cn : ChiCTR2300075405. The trial was prospectively registered on 4 September 2023.

Background: Left ventricular (LV) overload is a frequent complication during VA-ECMO associated with poor outcomes. Many strategies of LV unloading have been documented but lack of evidence shows which is better. We conducted a network meta-analysis to compare different LV unloading strategies. Methods: We searched databases for all published studies on LV unloading strategies during VA-ECMO. The pre-defined primary outcome was all-cause mortality. Results: 45 observational studies (34235 patients) were included. The Surface Under the Cumulative Ranking values (SUCRA) demonstrated that compared to no unloading strategy (15.4 %), IABP (73.8 %), pLVAD (60.8 %), atrial septostomy (51.2 %), catheter venting (48.8 %) were all associated with decreased all-cause mortality, in which IABP and pLVAD existed statistical significance. For secondary outcomes, no unloading group had the shortest VA-ECMO duration, ICU and hospital length of stay, and the lower risk of complications compared with unloading strategies. IABP was associated with reducing VA-ECMO duration, ICU and hospital length of stay, and the risk of complications (except for hemolysis as the second best) compared with other unloading strategies. Conclusions: LV unloading strategies during VA-ECMO were associated with improved survival compared to no unloading, but the tendency to increase the risk of various complications deserves more consideration.

Abstrct: Objectives: The FUWAI-SAVE system is a modified low-priming cardiopulmonary bypass (CPB) system. The study aimed to explore whether the FUWAI-SAVE system can reduce the perioperative blood transfusion and its impact on other postoperative complications during cardiac surgery. Metohds: This study was a single-center, single-blind, randomized controlled trial, registered at the Chinese Clinical Trial Registry (identifier: ChiCTR2100050488). Adult patients undergoing cardiac surgery with CPB and intermediate risk for transfusion risk stratification were randomly assigned to an intervention group (FUWAI-SAVE group) or a control group (conventional group). The primary endpoint of the study was the peri-CPB red blood cell transfusion (RBC) rate. The secondary endpoints included the transfusion rate of other blood products, the amount of blood products transfused, the incidence of major complications, in-hospital mortality, and others. Results: 360 patients were randomized from December 9, 2021, to January 30, 2023. The rate of the primary endpoint was significantly lower in the FUWAI-SAVE group compared to the control group [ OR (95%CI): 0.649 (0.424–0.994)]. Meanwhile, the amount of RBC transfusion during the peri-CPB period was significantly lower in the FUWAI-SAVE group compared to the control group, with a mean difference of −0.626 (−1.176 to −0.076) units. The occurrence rate of major complications did not differ significantly between the two groups. Conclusions: Among adult patients undergoing cardiac surgery with CPB, the application of the FUWAI-SAVE system significantly reduced RBC transfusion rate and amount. The FUWAI-SAVE system can be considered an important component of comprehensive blood management strategies in cardiac surgery.

ABSTRACT Introduction: Postoperative thrombocytopenia is common in cardiac surgery with cardiopulmonary bypass, and its risk factors are unclear. Methods: This retrospective study enrolled 3,175 adult patients undergoing valve surgeries with cardiopulmonary bypass from January 1, 2017 to December 30, 2018 in our institute. Postoperative thrombocytopenia was defined as the first postoperative platelet count below the 10th quantile in all the enrolled patients. Outcomes between patients with and without postoperative thrombocytopenia were compared. The primary outcome was in-hospital mortality. Risk factors of postoperative thrombocytopenia were assessed by logistic regression analysis. Results: The 10th quantile of all enrolled patients (75×109/L) was defined as the threshold for postoperative thrombocytopenia. In-hospital mortality was comparable between thrombocytopenia and non-thrombocytopenia groups (0.9% vs. 0.6%, P=0.434). Patients in the thrombocytopenia group had higher rate of postoperative blood transfusion (5.9% vs. 3.2%, P=0.014), more chest drainage volume (735 [550-1080] vs. 560 [430-730] ml, P 60 years (odds ratio [OR] 2.25, 95% confidence interval [CI] 1.345-3.765, P=0.002], preoperative thrombocytopenia (OR 18.671, 95% CI 13.649-25.542, P 60 years, small BSA, preoperative thrombocytopenia, and cardiopulmonary bypass time. BSA and isolated mitral valve surgery were negative predictors.

BackgroundLaboratory activated partial thromboplastin time (LAB-aPTT) is a widely used laboratory assay for monitoring unfractionated heparin (UFH) therapy during extracorporeal membrane oxygenation (ECMO). But LAB-aPTT is confined to a central laboratory, and the procedure is time-consuming. In comparison, point-of-care aPTT (POC-aPTT) is a convenient and quick assay, which might be a promising method for anticoagulation monitoring in ECMO. This study was aimed to evaluate the agreement between POC-aPTT (hemochron Jr. Signature instruments) and LAB-aPTT for anticoagulation monitoring in adult ECMO patients.MethodsData of ECMO-supported adult patients anticoagulated with UFH in our institute from January 2017 to December 2020 was retrospectively reviewed. POC-aPTT and LAB-aPTT results measured simultaneously were paired and included in the analysis. The correlation between POC-aPTT and LAB-aPTT was assessed using Spearman’s correlation coefficient. Bias between POC-aPTT and LAB-aPTT were described with the Bland-Altman method. Influence factors for bias were identified using multinomial logistic regression analysis.ResultsA total 286 pairs of aPTT results from 63 patients were included in the analysis. POC-aPTT and LAB-aPTT correlated weakly (r = 0.385, P < 0.001). The overall bias between POC-aPTT and LAB-aPTT was 7.78 [95%CI (−32.49, 48.05)] s. The overall bias between POC-aPTT and LAB-aPTT ratio (to normal value) was 0.54 [95%CI (−0.68, 1.76)]. A higher plasma fibrinogen level [OR 1.353 (1.057, 1.733), P = 0.017] was associated with a higher chance of POC-aPTT underestimating LAB-aPTT. While a lower plasma fibrinogen level [OR 0.809 (0.679, 0.963), P = 0.017] and lower UFH rate [OR 0.928 (0.868, 0.992), P = 0.029] were associated with a higher chance of POC-aPTT overestimating LAB-aPTT.ConclusionThe present study showed poor agreement between POC-aPTT and LAB-aPTT. POC-aPTT was not suitable for anticoagulation monitoring in adult ECMO patients.

Introduction: The egg shell membrane (ESM) is always considered as waste, but recent studies have shown that it has the potential to yield rapid re-endothelialization in vitro. We hypothesized that ESM and heparin-conjugated ESM (HESM) can be used as arterial patch in a rat aortic angioplasty model.Method: Sprague-Dawley rat (200 g) abdominal aortic patch angioplasty model was used. Decellularized rat thoracic aorta (TA) patch was used as the control; ESM patch was made of raw chicken egg; heparin-coated ESM (HESM) patch was made by using dopamine; anticoagulation properties were verified using platelet adhesion tests; the TA, ESM, and HESM patches were implanted to the rat aorta and harvested at day 14; and the samples were examined by immunohistochemistry and immunofluorescence.Result: The ESM patch showed a similar healing process to the TA patch; the cells could migrate and infiltrate into both patches; there was a neointima with von Willebrand factor-positive endothelial cells; the endothelial cells acquired arterial identity with Ephrin-B2- and dll-4-positive cells; there were proliferating cell nuclear antigen (PCNA)-positive cells, and PCNA and alpha smooth muscle actin dual-positive cells in the neointima in both groups. Heparin was conjugated to the patch successfully and showed a strong anticoagulation property in vitro. HESM could decrease mural thrombus formation after rat aortic patch angioplasty.Conclusion: The ESM is a natural scaffold that can be used as a vascular patch; it showed a similar healing process to decellularized TA patch; HESM showed anticoagulation property both in vitro and in vivo; and the ESM may be a promising vascular graft in the clinic.

Background: This study sought to evaluate the incidence of acute kidney injury (AKI) defined by the Kidney Disease: Improving Global Outcomes (KDIGO) group in patients supported by veno-arterial extracorporeal membrane oxygenation (VA ECMO) after post-cardiotomy cardiogenic shock (PCS), and to identify the risk factors for AKI ≥3. Methods: Patients with and without AKI ≥3 were divided into two groups. Potential risk factors for developing AKI ≥3 were evaluated by univariate logistic regression analysis. Patient risk factors (p < 0.1) in the univariate analysis were entered into the multivariable logistic regression model. The tolerance and variance inflation factors (VIF) were calculated to evaluate the collinearity of the potential variables. Results: 136 patients with a mean age of 53.6 ± 13.9 years (66.9% male) were enrolled in the study. 80 patients (58.8%) developed AKI ≥3. Patients with AKI ≥3 required significantly longer mechanical ventilation (200.9 [128.0, 534.8] hours vs. 78.9 [13.0, 233.0] hours, p < 0.001). The ICU stay and hospital stay of patients with AKI ≥3 were much longer than patients with AKI

Background: Large animal models are developed to help understand physiology and explore clinical translational significance in the continuous development of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) technology. The purpose of this study was to investigate the establishment methods and management strategies in an ovine model of VA-ECMO.Methods: Seven sheep underwent VA-ECMO support for 7 days by cannulation via the right jugular vein and artery. The animals were transferred into the monitoring cages after surgery and were kept awake after anesthesia recovery. The hydraulic parameters of ECMO, basic hemodynamics, mental state, and fed state of sheep were observed in real time. Blood gas analysis and activated clotting time (ACT) were tested every 6 h, while the complete blood count, blood chemistry, and coagulation tests were monitored every day. Sheep were euthanized after 7 days. Necropsy was performed and the main organs were removed for histopathological evaluation.Results: Five sheep survived and successfully weaned from ECMO. Two sheep died within 24–48 h of ECMO support. One animal died of fungal pneumonia caused by reflux aspiration, and the other died of hemorrhagic shock caused by bleeding at the left jugular artery cannulation site used for hemodynamic monitoring. During the experiment, the hemodynamics of the five sheep were stable. The animals stayed awake and freely ate hay and feed pellets and drank water. With no need for additional nutrition support or transfusion, the hemoglobin concentration and platelet count were in the normal reference range. The ECMO flow remained stable and the oxygenation performance of the oxygenator was satisfactory. No major adverse pathological injury occurred.Conclusions: The perioperative management strategies and animal care are the key points of the VA-ECMO model in conscious sheep. This model could be a platform for further research of disease animal models, pathophysiology exploration, and new equipment verification.

Airborne transmission of SARS-CoV-2 mostly occurs indoors, and effective mitigation strategies for specific building types are needed. Most guidance provided during the pandemic focused on general strategies that may not be applicable for all buildings. A systematic evaluation of infection risk mitigation strategies for different public and commercial buildings would facilitate their reopening process as well as post-pandemic operation. This study evaluates engineering mitigation strategies for five selected US Department of Energy prototype commercial buildings (i.e., Medium Office, Large Office, Small Hotel, Stand-Alone Retail, and Secondary School). The evaluation applied the multizone airflow and contaminant simulation software, CONTAM, with a newly developed CONTAM-quanta approach for infection risk assessment. The zone-to-zone quanta transmission and quanta fate were analyzed. The effectiveness of mechanical ventilation, and in-duct and in-room air treatment mitigation strategies were evaluated and compared. The efficacy of mitigation strategies was evaluated for full, 75%, 50% and 25% of design occupancy of these buildings under no-mask and mask-wearing conditions. Results suggested that for small spaces, in-duct air treatment would be insufficient for mitigating infection risks and additional in-room treatment devices would be needed. To avoid assessing mitigation strategies by simulating every building configuration, correlations of individual infection risk as a function of building mitigation parameters were developed upon extensive parametric studies.

Background: Extracorporeal membrane oxygenation (ECMO) provides cardiopulmonary support for critically ill patients. Portable ECMO devices can be applied in both in-hospital and out-of-hospital emergency conditions. We evaluated the safety and biocompatibility of a novel centrifugal pump and ECMO device of the OASSIST ECMO System (Jiangsu STMed Technologies Co., Suzhou, China) in a 168-h ovine ECMO model.Methods: The portable OASSIST ECMO system consists of the control console, the pump drive, and the disposable centrifugal pump. Ten healthy sheep were used to evaluate the OASSIST ECMO system. Five were supported on veno-venous ECMO and five on veno-arterial ECMO, each for 168 h. The systemic anticoagulation was achieved by continuous heparin infusion to maintain the activated clotting time (ACT) between 220 and 250 s. The rotary speed was set at 3,200–3,500 rpm. The ECMO configurations and ACT were recorded every 6 hours (h). The free hemoglobin (fHb), complete blood count, and coagulation action test were monitored, at the 6th h and every 24 h after the initiation of the ECMO. The dissection of the pump head and oxygenator were conducted to explore thrombosis.Results: Ten sheep successfully completed the study duration without device-related accidents. The pumps ran stably, and the ECMO flow ranged from 1.6 ± 0.1 to 2.0 ± 0.11 L/min in the V-V group, and from 1.8 ± 0.1 to 2.4 ± 0.14 L/min in the V-A group. The anticoagulation was well-performed. The ACT was maintained at 239.78 ± 36.31 s, no major bleeding or thrombosis was observed during the ECMO run or in the autopsy. 3/5 in the V-A group and 4/5 in the V-V group developed small thrombus in the bearing pedestal. No obvious thrombus formed in the oxygenator was observed. The hemolytic blood damage was not significant. The average fHb was 0.17 ± 0.12 g/L. Considering hemodilution, the hemoglobin, white blood cell, and platelets didn't reduce during the ECMO runs.Conclusions: The OASSIST ECMO system shows satisfactory safety and biocompatibility for the 168-h preclinical evaluation in the ovine model. The OASSIST ECMO system is promising to be applied in clinical conditions in the future.

Deep hypothermic circulatory arrest (DHCA) can induce systemic inflammatory response syndrome, including neuroinflammation. Finding suitable compounds is necessary for attenuating neuroinflammation and avoiding cerebral complications following DHCA. In the present study, we established DHCA rat models and monitored the vital signs during the surgical process. After surgery, we found significantly increased proinflammatory cytokines (IL-6, IL-1β, and TNF-α) in DHCA rats. Quantitative proteomics analysis was performed for exploring the differentially expressed proteins in hippocampus of DHCA rats and the data showed the adiponectin receptor 1 protein was upregulated. More importantly, administration of AdipoRon, a small-molecule adiponectin receptor agonist, could improve the basic vital signs and attenuate the increased IL-6, IL-1β, and TNF-α in DHCA rats. Furthermore, AdipoRon inhibits the activation of microglia (M1 state) and promotes their transition to an anti-inflammatory state, via promoting the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK), and downregulating nuclear factor kappa B (NF-κB) in DHCA rats. Consistently, we used LPS-treated BV2 cells to mimic the neuroinflammatory condition and found that AdipoRon dose-dependently decreased cytokines, along with increased phosphorylation of AMPK and downregulated NF-κB. In conclusion, our present data supported that AdipoRon inhibited DHCA-induced neuroinflammation via activating the hippocampal AMPK/NF-κB pathway.

Objective To investigate the use of the aortic balloon occlusion technique to assist total aortic arch replacement (TAR) with frozen elephant trunk (FET) to shorten the lower body circulatory arrest (CA) time and raise the nadir temperature during cardiopulmonary bypass. Methods This retrospective study reviewed consecutive patients that underwent aortic balloon occlusion to assist TAR with FET and patients that received conventional TAR with FET procedures. Preoperative characteristics, perioperative characteristics and postoperative outcomes were compared between the two groups. Results The study included130 patients treated with aortic balloon occlusion and 230 patients treated with conventional TAR with FET. The 30-day mortality rate was similar between the aortic balloon occlusion and conventional groups (4.62% versus 7.83%, respectively). Multivariate analysis showed that aortic balloon occlusion reduced the incidence of acute kidney injury, hepatic injury and red blood cell transfusion. The application of aortic balloon occlusion reduced the mean ± SD CA time from 17.24 ± 4.36 min to 6.33 ± 5.74 min, with the target nadir nasal temperature being increased from 25°C to 28°C. Conclusion The aortic balloon occlusion technique achieved significant improvements in reducing complications, but this did not translate into lower 30-day mortality.

Epstein-Barr virus-positive diffuse large B-cell lymphoma (EBV+DLBCL) is an aggressive malignancy that is largely resistant to current therapeutic regimens, and is an attractive target for immune-based therapies. Anti-programmed death-1 (PD-1) antibodies showed encouraging anti-tumor effects in both preclinical models and advanced solid and hematological malignancies, but its efficacy against EBV+DLBCL is unknown. Herein, we performed experiments using co-culture system with T cells and lymphoma cell lines including EBV+DLBCL and EBV-DLBCL [including germinal center B-cell like (GCB)-DLBCL and non-GCB-DLBCL] in vitro. We show that lymphoma cells augmented the expression of PD-1 on T cells, decreased the proliferation of T cells, and altered the secretion of multiple cytokines. However, through PD-1 blockade, these functions could be largely restored. Notbaly, the effect of PD-1 blockade on antitumor immunity was more effective in EBV+DLBCL than that in EBV-DLBCL in vitro. These results suggest that T-cell exhaustion and immune escape in microenvironment is one of the mechanisms underlying DLBCL; and PD-1 blockade could present as a efficacious immunotherapeutic treatment for EBV+DLBCL.

The article discusses a single-center retrospective study on using veno-arterial extracorporeal membrane oxygenation (V-A ECMO) to support patients with fulminant myocarditis (FM). FM is a severe inflammatory cardiac disease that can lead to sudden heart failure or death. V-A ECMO has been effective in stabilizing hemodynamics, assisting patients through crises, and bridging them to recovery or advanced therapies. The study included 16 adult patients with FM who received V-A ECMO support, with 56.3% surviving and 43.8% expiring during hospitalization. The study highlights the effectiveness of V-A ECMO in supporting FM patients and the potential for bridging them to recovery or advanced therapies. [Extracted from the article]

Abstract Advanced biofabrication techniques can create tissue-like constructs that can be applied for reconstructive surgery or as in vitro three-dimensional (3D) models for disease modeling and drug screening. While various biofabrication techniques have recently been widely reviewed in the literature, acoustics-based technologies still need to be explored. The rapidly increasing number of publications in the past two decades exploring the application of acoustic technologies highlights the tremendous potential of these technologies. In this review, we contend that acoustics-based methods can address many limitations inherent in other biofabrication techniques due to their unique advantages: noncontact manipulation, biocompatibility, deep tissue penetrability, versatility, precision in-scaffold control, high-throughput capabilities, and the ability to assemble multilayered structures. We discuss the mechanisms by which acoustics directly dictate cell assembly across various biostructures and examine how the advent of novel acoustic technologies, along with their integration with traditional methods, offers innovative solutions for enhancing the functionality of organoids. Acoustic technologies are poised to address fundamental challenges in biofabrication and tissue engineering and show promise for advancing the field in the coming years.

Abstract Separating plasma from whole blood is an important sample processing technique required for fundamental biomedical research, medical diagnostics, and therapeutic applications. Traditional protocols for plasma isolation require multiple centrifugation steps or multiunit microfluidic processing to sequentially remove large red blood cells (RBCs) and white blood cells (WBCs), followed by the removal of small platelets. Here, we present an acoustofluidic platform capable of efficiently removing RBCs, WBCs, and platelets from whole blood in a single step. By leveraging differences in the acoustic impedances of fluids, our device generates significantly greater forces on suspended particles than conventional microfluidic approaches, enabling the removal of both large blood cells and smaller platelets in a single unit. As a result, undiluted human whole blood can be processed by our device to remove both blood cells and platelets (>90%) at low voltages (25 Vpp). The ability to successfully remove blood cells and platelets from plasma without altering the properties of the proteins and antibodies present creates numerous potential applications for our platform in biomedical research, as well as plasma-based diagnostics and therapeutics. Furthermore, the microfluidic nature of our device offers advantages such as portability, cost efficiency, and the ability to process small-volume samples.

Introduction: Postoperative thrombocytopenia is common in cardiac surgery with cardiopulmonary bypass, and its risk factors are unclear. Methods: This retrospective study enrolled 3,175 adult patients undergoing valve surgeries with cardiopulmonary bypass from January 1, 2017 to December 30, 2018 in our institute. Postoperative thrombocytopenia was defined as the first postoperative platelet count below the 10th quantile in all the enrolled patients. Outcomes between patients with and without postoperative thrombocytopenia were compared. The primary outcome was in-hospital mortality. Risk factors of postoperative thrombocytopenia were assessed by logistic regression analysis. Results: The 10th quantile of all enrolled patients (75×109/L) was defined as the threshold for postoperative thrombocytopenia. In-hospital mortality was comparable between thrombocytopenia and non-thrombocytopenia groups (0.9% vs. 0.6%, P=0.434). Patients in the thrombocytopenia group had higher rate of postoperative blood transfusion (5.9% vs. 3.2%, P=0.014), more chest drainage volume (735 [550-1080] vs. 560 [430-730] ml, P<0.001), and higher incidence of acute kidney injury (12.3% vs. 4.2%, P<0.001). Age > 60 years (odds ratio [OR] 2.25, 95% confidence interval [CI] 1.345-3.765, P=0.002], preoperative thrombocytopenia (OR 18.671, 95% CI 13.649-25.542, P<0.001), and cardiopulmonary bypass time (OR 1.088, 95% CI 1.059-1.117, P<0.001) were positively independently associated with postoperative thrombocytopenia. Body surface area (BSA) (OR 0.247, 95% CI 0.114-0.538, P<0.001) and isolated mitral valve surgery (OR 0.475, 95% CI 0.294-0.77) were negatively independently associated with postoperative thrombocytopenia. Conclusion: Positive predictors for thrombocytopenia after valve surgery included age > 60 years, small BSA, preoperative thrombocytopenia, and cardiopulmonary bypass time. BSA and isolated mitral valve surgery were negative predictors. [ABSTRACT FROM AUTHOR]

Abstract Hepatocellular carcinoma (HCC) is a prevalent primary liver cancer often associated with chronic hepatitis B virus infection (CHB) and liver cirrhosis (LC), underscoring the critical need for biomarker discovery to improve patient outcomes. Emerging as a promising avenue for biomarker development, proteomic technology leveraging liquid biopsy from small extracellular vesicles (sEV) offers new insights. Here, we evaluated various methods for sEV isolation and identified polysaccharide chitosan (CS) as an optimal approach. Subsequently, we employed optimized CS‐based magnetic beads (Mag‐CS) for sEV separation from serum samples of healthy controls, CHB, LC, and HBV‐HCC patients. Leveraging data‐independent acquisition mass spectrometry coupled with machine learning, we uncovered potential vesicular protein biomarker signatures (KNG1, F11, KLKB1, CAPNS1, CDH1, CPN2, NME2) capable of distinguishing HBV‐HCC from CHB, LC, and non‐HCC conditions. Collectively, our findings highlight the utility of Mag‐CS‐based sEV isolation for identifying early detection biomarkers in HBV‐HCC.

Urban ecological security is not only a basic safety requirement for human security and development, but also an important part of national security and other security and infrastructure carriers. Protecting the environment is an important factor in the construction of China's natural civilization. In recent years, with the deterioration of the environment, the region and its people have paid more and more attention to the safety of urban ecological environment, which has become one of the hottest issues in current research. Land use/cover rate change (LUCC) affects the environment, which will also affect environmental safety, and changes in its appearance will also affect nature and the environment, providing a positive impetus for the control of natural processes. In this paper, researches on the above problems in City K and Zhengzhou are carried out, using MSPA and visual image forms to better connect local resources, and through the MCR model based on ecological control, a weight-based multi-structure network model is established, which is conducive to the establishment of a multi-structure network model based on ecological control. Build a city of environmental science network. The GIS control line was explored, and the concept of the control line was filled to a certain extent. At the same time, taking City K and Zhengzhou as examples, determining the breadth of their layout and management, as well as the control strategy of their environmental control lines, provides a specific reference angle for the layout and research of other cities. Urban ecological security is very important to each of us living in cities. It is a difficult problem at this stage to establish an ecological security model to open a new security pattern.

Abstract The addition of surface acoustic wave (SAW) technologies to microfluidics has greatly advanced lab-on-a-chip applications due to their unique and powerful attributes, including high-precision manipulation, versatility, integrability, biocompatibility, contactless nature, and rapid actuation. However, the development of SAW microfluidic devices is limited by complex and time-consuming micro/nanofabrication techniques and access to cleanroom facilities for multistep photolithography and vacuum-based processing. To simplify the fabrication of SAW microfluidic devices with customizable dimensions and functions, we utilized the additive manufacturing technique of aerosol jet printing. We successfully fabricated customized SAW microfluidic devices of varying materials, including silver nanowires, graphene, and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). To characterize and compare the acoustic actuation performance of these aerosol jet printed SAW microfluidic devices with their cleanroom-fabricated counterparts, the wave displacements and resonant frequencies of the different fabricated devices were directly measured through scanning laser Doppler vibrometry. Finally, to exhibit the capability of the aerosol jet printed devices for lab-on-a-chip applications, we successfully conducted acoustic streaming and particle concentration experiments. Overall, we demonstrated a novel solution-based, direct-write, single-step, cleanroom-free additive manufacturing technique to rapidly develop SAW microfluidic devices that shows viability for applications in the fields of biology, chemistry, engineering, and medicine.