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The 2-nitroimidazole based 99mTc-radiopharmaceuticals are widely explored for imaging tumor hypoxia. Radiopharmaceuticals for targeting hypoxia are often lipophilic and therefore, show significant uptake in liver and other vital organs. In this context, lipophilic radiopharmaceuticals with design features enabling faster clearance from liver may be more desirable. A dipicolylamine-NCS bifunctional chelator that could generate a thiourea-bridge up on conjugation to primary amine bearing molecule was used to synthesize a 2-nitroimidazole-dipicolyl amine ligand for radiolabeling with 99mTc(CO)3 core. Corresponding Re(CO)3-analogue was prepared to establish the structure of 2-nitroimidazole-99mTc(CO)3 complex prepared in trace level. The 2-nitroimidazole-99mTc(CO)3 complex showed a hypoxic to normoxic ratio of ~2.5 in CHO cells at 3 h. In vivo, the complex showed accumulation and retention in tumor with high tumor to blood and tumor to muscle ratio. The study demonstrated the utility of metabolizable thiourea-bridge in 2-nitroimidazole-99mTc(CO)3 complex in inducing faster clearance of the radiotracer from liver. The dipicolylamine-NCS bifunctional chelator reported herein can also be used for radiolabeling other class of target specific molecules with 99mTc(CO)3 core.

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Health care disparities between high-income countries (HICs) and low- and middle-income countries (LMICs) are well established. The focus of the surgical aspect of health was identified in the early twenty-first century, and efforts to provide safe surgical intervention require the shift of resources from HICs to LMICs with specialized surgeons, anesthesiologists, and equipment. This intervention may make a difference on the short run; however, to achieve a long-term self-sustaining surgical service in the region of need, education and training of local physicians is key.

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For the first time, explicit stabilization of all the three conformers, viz. (cis,cis), (cis,trans) and (trans,trans), of a 'nano-sized' highly-flexible urea-bridged Zn(II)porphyrin dimer have been achieved via careful manipulations of external stimuli such as solvent dielectrics, temperature, anionic interactions, axial ligation and surface-induced stabilization. The conformers differ widely in their structures, chemical and photophysical properties and thus have vast potential applicability. X-ray structural characterizations have been reported for the (cis,cis) and (cis,trans)-conformers. While (cis,cis) conformer stabilized exclusively in dichloromethane, more polar solvents resulted in the stabilization of (cis,trans) and (trans,trans)-conformers. Low temperature promotes the stabilization of (cis,trans)-conformer while rise in temperature facilitates flipping to the (cis,cis) one. Significantly, exclusive stabilization of the (trans,trans)-isomer has been illustrated using acetate anion which facilitates H-bonding with the two amide linkages of the urea spacer. Remarkably, HOPG surface facilitates stabilization of the energetically challenging (trans,trans)-conformer via CH···p and p···p interactions with the solid surface to the porphyrinic cores. DFT calculations demonstrate that the relative stability of the conformers can be modulated upon slight external perturbations as also observed in the experiment. Several factors contributing towards the conformational landscape for the highly flexible urea-bridged porphyrin dimers have been mapped.

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This study introduces an approach for converting the current from a sensor into controllable voltage. To this end, a switched-capacitor structure was integrated to provide efficient current-to-voltage conversion. The generated voltage was further regulated by an operational amplifier current source, enhancing stability and precision. An n-type metal oxide semiconductor field-effect transistor structure under an H-bridge was integrated into the system to achieve fine-tuned control over current stimulation. This component contributed to voltage regulation and enabled bi-directional control of current flow, offering versatility in adjusting current amplitudes using working and counter electrodes. This dynamic control mechanism was pivotal for effectively controlling the intensity of current stimulation. We applied Verilog-A modeling to simulate the optical characteristics of Si nanowires. The proposed system efficiently converted sensor-derived current into voltage using a switched-capacitor structure. Simultaneously, the precision was enhanced via operational amplifier regulation and n-type metal-oxide-semiconductor field-effect transistor-based H-bridge control. The simulation showed a current stimulus amplitude ranging from 2 to 13 µA for a variable photocurrent of Si nanowires (Rex: 10 kΩ, pulse: 100 Hz, 1 ms). The ability to finely control current stimulation intensity holds promise for diverse applications requiring accurate and adjustable current manipulation. This study contributes to the growing field of sensor technology by offering a unique perspective on the integration of nanostructures and electronic components for an enhanced control and functionality.

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The Fenshui River Bridge is a steel-concrete composite girder bridge with a main span of 90 m. Due to the topographical constraints, the steel box girder was constructed without the use of auxiliary piers, employing incremental launching techniques. This article focuses on the construction technology used for the steel box girder of the Fenshui River Bridge. Firstly, using the influence matrix method, the cable force is determined based on the maximum cantilever state of the structure, with the vertical deformation of the front end of the guide beam and the horizontal deformation of the top of the tower as the control objectives. The unstressed cable length is then calculated based on the mechanical relationship between cable deformation and cable force. A calculation method for adaptive cable force is proposed, which is based on the variation of the stress-free cable length within the adaptive structural system. Next, the finite element analysis method was employed to determine the optimal layout position for the tower. The results indicate that during the incremental launching construction of the steel box girder, the calculated cable forces using the method proposed in this paper are in close agreement with the measured cable forces. At the maximum cantilever state of the structure, the calculated and measured values of the cable force resulted in a percentage difference of 3.96%. The calculated values of deformation and stress in key sections showed a percentage difference of 6.4% for deformation and 6.6% for stress. To maximize the effectiveness of the tower and cable, the tower should be positioned above the bridge pier when the guide beam crosses the maximum span. The findings of this paper can serve as a reference for the construction of similar types of bridges.

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Introduction: Heterotopic ossification of the Achilles tendon (HOTA) is a rare but consequential complication to an inflammatory event, often presenting challenges in diagnosis and management. Case Report: We report a case of a 42-year-old male with Type II diabetes mellitus, managed with Metformin, who presented with acute pain and swelling in the right ankle following a running activity. Clinical examination revealed tenderness and a visible swelling proximal to the calcaneum attachment of the tendon which was hard in consistency, and a positive Thompson test indicative of a potential Achilles tendon injury. Imaging, including X-ray and magnetic resonance imaging, confirmed a complete avulsion tear with cranial retraction of the torn tendon and heterotopic ossification seen proximal to the torn end of the tendon. Surgical intervention, employing a posterior paramedian approach under tourniquet control, involved tendon approximation using the Speed bridge technique, incision over the proximal tendon and removal of the ossified tendon, and repair of the incised tendon sheath. Postoperatively, the patient received a tailored medication regimen and was advised strict non-weight-bearing measures, wound management, and limb elevation. The patient was discharged in a stable condition. Conclusion: This case underscores the importance of early recognition and prompt surgical intervention in managing HOTA, particularly in patients with underlying risk factors. The presented surgical approach and postoperative management contribute to the evolving strategies for addressing this rare clinically significant condition.

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BACKGROUND: Severe obesity greatly influences the difficulty of colorectal cancer surgery and has been reported to prolong operative time, increase the rate of laparotomy, and elevate increase postoperative complications. We investigated the efficacy of laparoscopic sleeve gastrectomy (LSG) for preoperative weight loss to ensure safe colorectal cancer surgery. CASE PRESENTATION: A 51 year-old female with a body mass index of 43.5 kg/m2 was referred to our hospital due to a positive fecal occult blood test. She was diagnosed as having a laterally spreading tumor of the cecum by colonoscopy. Endoscopic submucosal dissection was attempted but proved difficult due to the size of the lesion and its proximity to the appendiceal orifice. We planned bariatric surgery prior to colorectal surgery, and she underwent LSG without any complications. Seven months after the LSG, she had lost 30.7 kg, and her final preoperative body mass index was 27.8 kg/m2. Single-incision laparoscopic ileocecal resection was then performed safely. The pathological diagnosis was adenocarcinoma in adenoma of the cecum, TisN0M0. CONCLUSION: LSG was effective in reducing visceral fat and making it possible to perform safe surgery for colorectal cancer in a severely obese patient.

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OBJECTIVE: Impella 5.5 (Abiomed, Danvers, MA, USA) is a temporary mechanical circulatory support device used for patients in cardiogenic shock. This review provides a comprehensive overview of the device's clinical effectiveness, safety profile, patient outcomes, and relevant procedural considerations. METHODS: We conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed/MEDLINE database. The search query included articles available from October 6, 2022, through January 13, 2023. Our initial search identified 75 studies. All records were screened by 2 independent reviewers using the Covidence software for adherence to our inclusion criteria, and 8 retrospective cohort studies were identified as appropriate for inclusion. RESULTS: Across the included studies, the sample size ranged from 4 to 275, with predominantly male cohorts. Indications for Impella support varied, and the duration of support ranged from 9.8 to 70 days. Overall, Impella support appeared to be associated with favorable survival rates and manageable complications in various patient populations. Complications associated with Impella use included bleeding, stroke, and device malfunctions. Two studies compared prolonged and Food and Drug Administration-approved Impella support, showing similar outcomes and adverse events. CONCLUSIONS: Impella 5.5 continues to be an attractive option for bridging patients to definitive therapy. Survival during and after Impella 5.5 was favorable for patients regardless of initial indication. However, device use was associated with several important complications, which calls for judicious use and a precontemplated exit strategy. Limitations of this literature review include biases inherent to the retrospective studies included, such as selection and publication bias.

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Elevated stations are integral components of urban rail transit systems, significantly impacting passengers' travel experience and the operational efficiency of the transportation system. However, current elevated station designs often do not sufficiently consider the structural dynamic response under various operating conditions. This oversight can limit the operational efficiency of the stations and pose potential safety hazards. Addressing this issue, this study establishes a vehicle-bridge-station spatial coupling vibration simulation model utilizing the self-developed software GSAP V1.0, focusing on integrated station-bridge and combined station-bridge elevated station designs. The simulation results are meticulously compared with field data to ensure the fidelity of the model. Analyzing the dynamic response of the station in relation to train parameters reveals significant insights. Notably, under similar travel conditions, integrated stations exhibit lower vertical acceleration in the rail-bearing layer compared to combined stations, while the vertical acceleration patterns at the platform and hall layers demonstrate contrasting behaviors. At lower speeds, the vertical acceleration at the station concourse level is comparable for both station types, yet integrated stations exhibit notably higher platform-level acceleration. Conversely, under high-speed conditions, integrated stations show increased vertical acceleration at the platform and hall levels compared to combined stations, particularly under unloaded double-line working conditions, indicating a superior dynamic performance of combined stations in complex operational scenarios. However, challenges such as increased station height due to bridge box girder maintenance, track layer waterproofing, and track girder support maintenance exist for combined stations, warranting comprehensive evaluation for station selection. Further analysis of integrated station-bridge structures reveals that adjustments in the floor slab thickness at the rail-bearing and platform levels significantly reduce dynamic responses, whereas increasing the rail beam height notably diminishes displacement responses. Conversely, alterations in the waiting hall floor slab thickness and frame column cross-sections exhibit a minimal impact on the station dynamics. Overall, optimizing structural dimensions can effectively mitigate dynamic responses, offering valuable insights for station design and operation.

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Maglev vehicles apply the entire vehicle load uniformly onto bridges through levitation forces. In assessing the dynamic characteristics of the maglev train-bridge coupling system, it is reasonable to simplify the distributed levitation force as a concentrated force. This article theoretically derives the analytical response of bridge dynamics under the action of a single constant force and conducts numerical simulations for a moving single constant force and a series of equally spaced constant forces passing over simply supported beams and two-span continuous beams, respectively. The topic of discussion is the response of bridge dynamics when different degrees of force concentration are involved. High-precision displacement and acceleration sensors were utilized to conduct tests on the Shanghai maglev line to verify the accuracy of the simulation results. The results indicate that when simplifying the distributed levitation force into a concentrated force model, a frequency ratio can be used to analyze the conditions for resonance between the train and the bridge and to calculate the critical speed of the train; the levitation distribution force of a high-speed maglev vehicle can be simplified into four groups of concentrated forces based on the number of levitation frames to achieve sufficient accuracy, with the dynamic response of the bridge being close to that under distributed loads.

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Of the 100,000 railroad bridges in the United States, 50% are over 100 years old. Many of these bridges do not meet the minimum vertical clearance standards, making them susceptible to impact from over-height vehicles. The impact can cause structural damage and unwanted disruption to railroad bridge services; rapid notification of the railroad authorities is crucial to ensure that the bridges are safe for continued use and to affect timely repairs. Therefore, researchers have developed approaches to identify these impacts on railroad bridges. Some recent approaches use machine learning to more effectively identify impacts from the sensor data. Typically, the collected sensor data are transmitted to a central location for processing. However, the challenge with this centralized approach is that the transfer of data to a central location can take considerable time, which is undesirable for time-sensitive events, like impact detection, that require a rapid assessment and response to potential damage. To address the challenges posed by the centralized approach, this study develops a framework for edge implementation of machine-learning predictions on wireless smart sensors. Wireless sensors are used because of their ease of installation and lower costs compared to their wired counterparts. The framework is implemented on the Xnode wireless smart sensor platform, thus bringing artificial intelligence models directly to the sensor nodes and eliminating the need to transfer data to a central location for processing. This framework is demonstrated using data obtained from events on a railroad bridge near Chicago; results illustrate the efficacy of the proposed edge computing framework for such time-sensitive structural health monitoring applications.

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Precise finite element modeling is critically important for the construction and maintenance of long-span suspension bridges. During the process of modeling, shape-finding and model calibration directly impact the accuracy and reliability. Scholars have provided numerous alternative proposals for the shape-finding of main cables in suspension bridges from both theoretical and finite element analysis perspectives. However, it is difficult to apply these solutions to suspension bridges with special components. Seeking a viable solution for such suspension bridges holds practical significance. The Nanjing Qixiashan Yangtze River Bridge is the first three-span suspension bridge in China. To maintain the configuration of the main cable, the suspension bridge is equipped with specialized suspenders near the anchors, referred to as displacement-limiting suspenders. It is the first suspension bridge in China to use displacement-limiting suspenders and their anchorage system. Taking the suspension bridge as a research background, this paper introduces a refined finite element modeling approach considering the effect of geometric nonlinearity. Firstly, based on the loop adjustment and temperature correction, the shape-finding and force assessment of the main cables are carried out. On this basis, a nonlinear finite element model of the bridge was established and calibrated, taking into account factors such as pylon settlement and cable saddle precession. Finally, the static and dynamic characteristics of the suspension bridge were thoroughly investigated. This study aims to provide a reference for the design, construction and operation of the three-span continuous suspension bridge.

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A portable axial-flow polymer bridge pump with hydrodynamic bearings has been developed for bridge-to-bridge use. The pump is inexpensive to manufacture and disposable. It weighs 185 g and was verified to have a lifetime of 3 months with silent operation. For partial circulatory assist at a flow rate of 2 L/min, the clinical limit of hemolysis was verified for a rotational speed below 9000 rpm, at which a pressure of 100 mmHg was generated. In an anti-thrombogenic test, the pump stably operated for 6 h without thrombus formation.

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BACKGROUND: Since United Network for Organ Sharing (UNOS) revised their heart allocation policy in 2018, usage of veno-arterial extracorporeal life support (VA-ECLS) has dramatically increased as a bridge to transplant. This study investigated outcomes of VA-ECLS patients bridged to simultaneous heart-kidney transplant (SHK) in the new policy era. METHODS: This study included 774 adult patients from the UNOS database who received SHK between 10/18/18 and 12/31/21 and compared patients bridged to transplant on VA-ECLS (n = 50) with those not bridged (n = 724). RESULTS: At baseline, SHK recipients bridged from VA-ECLS were younger (50.5 vs 58.0 years, p = 0.007), had higher estimated glomerular filtration rate (eGFR) at time of transplant (47.6 vs 30.1, p < 0.001), and spent fewer days on the waitlist (7.0 vs 33.5 days, p < 0.001). In the perioperative period, VA-ECLS was associated with higher rates of temporary dialysis (56.0% vs 28.0%, p < 0.001) but similar 2-year cumulative incidence of chronic dialysis (7.5% vs 5.4%, p = 0.800) and renal allograft failure (12.0% vs 8.1%, p = 0.500) compared to non-ECLS cohort. However, VA-ECLS patients had decreased survival to discharge (76.0% vs 92.7%, p < 0.001) and 2-year post-transplant survival (71.7% vs 83.0%, p = 0.004), as well as greater 2-year cumulative incidence of cardiac allograft failure (10.0% vs 2.7%, p = 0.002). Multivariable analyses found VA-ECLS at time of transplant to be independently associated with 2-year post-transplant mortality (HR [95% CI]: 3.40 [1.66-6.96], p = 0.001) and cardiac allograft failure (sub-distribution hazard ratio [SHR] [95% CI]: 8.51 [2.77-26.09], p < 0.001). CONCLUSION: Under the new allocation policy, patients bridged to SHK from VA-ECLS displayed greater early mortality and cardiac allograft failure but similar renal outcomes compared to non-ECLS counterparts.

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Girder shifting is a common form of seismic damage for girder bridges. Unseating could occur when the displacement of the girder is too large, especially for bridges near faults, because the velocity impulse effect leads to greater displacement responses of structures. Setting metal dampers between girders and piers is a useful way to control the seismic behavior and reduce the risk of unseating. Since metal dampers are inevitably exposed to the erosive service environments, their mechanical properties may degrade due to corrosion. In this paper, a U-shaped metal damper made of stainless steel instead of mild steel (i.e., U-shaped stainless steel damper, which could be named simply as USSSD) is proposed and applied to the seismic reduction design of girder bridges. First, the finite element model (FEM) of the USSSD is built by the ABAQUS, and its force-displacement relationship is obtained based on the skeleton curve, which is fitted by the trilinear kinematic strengthening model. Then, a multi-union long simply supported girder bridge is taken as an example. The FEM of the adopted bridge is established via the Midas Civil to verify the seismic mitigation effect of the proposed USSSD excited by near-fault ground motions. The numerical analyses demonstrate that the unseating may occur without the use of the USSSDs. The relative displacement between the girder and pier is effectively controlled by the USSSDs, and the reduction is more than 50 %. When the bridge is equipped with the USSSDs, both the curvature ductility coefficient of the pier bottom and the maximum drift of the pier tip increase by a limited amplitude, which do not cause additional damage to the piers.

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Tied-arch bridges, a vital component of modern infrastructure, are susceptible to various forms of damage, particularly hangers. The detection and identification of such damages are crucial for maintaining structural integrity and safety. However, traditional methods face challenges in terms of accuracy and efficiency. This study aims to develop a refined method for hanger damage identification in tied-arch bridges, to address the limitations of existing techniques. By focusing on deflection changes at the anchoring points between the hangers and tie beams, we sought to enhance the precision of damage detection. We propose an innovative approach based on the concept of influence lines, introducing the 'generalized deflection difference influence line'and the 'deflection difference influence matrix'. Then proposed a new identification index for identifying the damaged hanger after matrix. An actual tied-arch bridge was used to validate the proposed approach. A detailed three-dimensional finite element model of the bridge was developed and calibrated using dynamic and static response data. Thirty different hanger-damage conditions were simulated to evaluate the effectiveness of the proposed method. Our findings reveal that the deflection difference influence matrix offers more detailed and comprehensive information on bridge distribution points than traditional methods. Our method proved effective in identifying hanger damage, irrespective of its location on the bridge. In additionally, the identification efficiency of the method can be improved by adjusting the magnitude of the applied load, with larger loads amplifying the detectability of damage. This study highlights the potential of the deflection difference influence matrix to revolutionize hanger damage identification for tied-arch bridges. Its adaptability, accuracy, and efficiency are significant advancements over existing methods. This study successfully demonstrates an innovative and reliable method for hanger damage identification.

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AIMS: Restricting access to means by installing physical barriers has been shown to be the most effective intervention in preventing jumping suicides on bridges. However, little is known about the effectiveness of partial restriction with interventions that still allow jumping from the bridge. METHODS: This study used a quasi-experimental design. Public sites that met our inclusion criteria were identified using Google search and data on jumping suicides on Bridge A (South Korea), Bridges B and C (the United States) and Bridge D (Canada) were obtained from the relevant datasets. Incidence rate ratios (IRRs) were estimated using Poisson regressions comparing suicide numbers before and after the installation of physical structures at each site. RESULTS: Fences with sensor wires and spinning handrails installed above existing railings on the Bridge A, and fences at each side of the entrances and the midpoint of main suspension cables on the Bridge D were associated with significant reductions in suicides (IRR 0.37, 95% Confidence Interval (CI) 0.26 - 0.54; 0.26, 95% CI 0.09 - 0.76). Installation of bird spike on the parapet on the Bridge B, and fences at the front of seating alcoves on the Bridge C were not associated with changes in suicides (1.21, 95% CI 0.88 - 1.68; 1.49, 95% CI 0.56 - 3.98). CONCLUSIONS: Partial means restriction (such as fences with sensor wires and spinning bars at the top, and partial fencing at selected points) on bridges appears to be helpful in preventing suicide. Although these interventions are unlikely to be as effective as interventions that fully secure the bridge and completely prevent jumping, they might best be thought of as temporary solutions before more complete or permanent structures are implemented.

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Myocardial bridging (MB) is a common anatomic variant in coronary arteries with unclear functional significance. We evaluated regional myocardial strain by speckle tracking during dobutamine stress echocardiography (DSE) in patients with MB in the left anterior descending coronary artery (LAD). We studied 11 patients with MB in the LAD and no obstructive coronary artery disease (CAD), 7 patients without MB, but obstructive CAD in the LAD, and 12 controls without MB or obstructive CAD. MB was defined as either > 1 mm (superficial) or > 2 mm (deep) intramyocardial course of the LAD in coronary CT angiography. Regional longitudinal, radial and circumferential strains and strain rates as well as post-systolic strain index (PSI) were measured at rest, peak stress, and early recovery (1 min after stress). Strain parameters during DSE were similar in the myocardium distal to MB and other myocardial regions of the same patients as well as the LAD territory in controls. However, patients with obstructive CAD showed impaired LS and strain rate as well as increased PSI at peak stress. None of the MB was associated with systolic compression in invasive coronary angiography and strain parameters were similar between superficial and deep MB. Stress myocardial blood flow by positron emission tomography correlated with LS and RS at peak stress in the myocardium distal to MB (r = - 0.73, p = 0.03, and r = 0.64, p = 0.04, respectively). Myocardial strain is not reduced during DSE in patients with MB in the LAD and no significant systolic compression.

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Intravital microscopy (IVM) is a valuable method for biomedical characterization of dynamic processes, which has been applied to many fields such as neuroscience, oncology, and immunology. During IVM, vibration suppression is a major challenge due to the inevitable respiration and heartbeat from live animals. In this study, taking liver IVM as an example, we have unraveled the vibration inhibition effect of liquid bridges by studying the friction characteristics of a moist surface on the mouse liver. We confirmed the presence of liquid bridges on the liver through fluorescence imaging, which can provide microscale and nondestructive liquid connections between adjacent surfaces. Liquid bridges were constructed to sufficiently stabilize the liver after abdominal dissection by covering it with a polymer film, taking advantage of the high adhesion properties of liquid bridges. We further prototyped a microscope-integrated vibration-damping device with adjustable film tension to simplify the sample preparation procedure, which remarkably decreased the liver vibration. In practical application scenarios, we observed the process of liposome phagocytosis by liver Kupffer cells with significantly improved image and video quality. Collectively, our method not only provided a feasible solution to vibration suppression in the field of IVM, but also has the potential to be applied to vibration damping of precision instruments or other fields that require nondestructive ″soft″ vibration damping.