Rescue Method Research Articles

Identification of Endosonographic Features that Compromise EUS-FNB Diagnostic Accuracy in Pancreatic Masses.

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is highly accurate for diagnosing pancreatic mass. However, making diagnosis is challenging in 5-20% of patients. This study investigated the challenging features associated with reduced diagnostic performance in EUS-FNB and potential rescue methods that can improve the diagnostic rate. This single-center retrospective study included patients with solid pancreatic tumors who underwent EUS-FNB between January 1, 2019, and December 12, 2021. Patients without a computed tomography (CT) scan or definite diagnosis were excluded. Challenging features were features that reduced diagnostic accuracy in EUS-FNB, as determined through multivariate analysis. Rescue methods were methods that assisted operators in assessing lesions in patients with challenging features. Of 332 enrolled patients, an accurate diagnosis obtained using EUS-FNB was achieved in 286 (86.1%). Univariable analysis revealed that the diagnostic accuracy was lower in cases of pancreatic tumors with isoattenuation in CT images (77.3% vs. 89.8%, odds ratio [OR]: 0.39, p = 0.003), an ill-defined margin on EUS (61.2% vs. 92.5%, OR: 0.13, p < 0.001), or tumor size < 20mm (65.5% vs. 88.1%, OR: 0.26, p = 0.002). However, only ill-defined margins on EUS (OR: 0.14, p < 0.001) and tumor size < 20mm (OR: 0.25, p = 0.005) were independent predictors of inconclusive EUS-FNB in the multivariate analysis. The use of contrast (OR: 4.46, p = 0.026) and a highly experienced endosonographer (> 5cases/month; OR: 3.25, p = 0.034) improved diagnostic performance in difficult cases. Pancreatic tumors with ill-defined tumor margins on EUS or size < 20mm are challenging features in EUS-FNB. The use of contrast and a highly experienced endosonographer can improve diagnostic performance in difficult cases.

Endoscopic ultrasound-guided biliary rendezvous after failed cannulation, and comparison between benign vs malignant biliopancreatic disorders: outcomes at a single tertiary-care centre

Background Endoscopic ultrasound (EUS)-guided biliary rendezvous (RV) is an EUS-assisted technique described as a rescue method in cases of failed biliary cannulation via endoscopic retrograde cholangiography (ERC). Current literature remains unclear regarding its current role. The study aim was to evaluate the effectiveness for biliary EUS-RV, and comparison between benign vs malignant biliopancreatic disorders. Methods Retrospective observational study with prospective consecutive inclusion in a specific database from a tertiary-center. All patients with biliopancreatic diseases that underwent a EUS-assisted ERC between October-2010 and November-2022 for failed ERC were included. Main outcomes were technical/overall success. Secondary outcomes were safety, potential factors related to failure/success or safety; and a comparative analysis between EUS-RV and EUS-guided transmural drainage (TMD) in malignant cases. Results A total of 69 patients who underwent EUS-RV procedures, with benign and malignant pathologies (n = 40 vs n = 29), were included. Technical / overall success and related-adverse events (AEs) were 79.7% (95%CI, 68.3-88.4) / 74% (95%CI, 61-83.7) and 24% (95%CI, 15.1-36.5), respectively. Failed cases were mainly related with guidewire manipulation. Seven failed RV were successfully rescued by EUS-TMD. On multivariable analysis, EUS-RV and malignant pathology was associated with a greater failure rate (technical success: OR,0.21; 95%CI,0.05-0.72; p = 0.017), and higher AEs rate (OR,3.46; 95%CI,1.13-11.5; p = 0.034). Also, the EUS-TMD group had greater technical success (OR,16.96; 95%CI,4.69-81.62; p < 0.001) and overall success (OR, 3.09; 95%CI,1.18-8-16; p < 0.026) with a lower AEs rate (OR,0.30; 95%CI,0.11-0.78; p = 0.014) than EUS-RV in malignant disorders. Conclusions EUS-RV is a demanding technique with better outcomes in benign than in malignant biliopancreatic diseases. Comparison of the EUS-TMD group on malignant disorders showed worse outcomes with EUS-RV. Given these findings, maybe EUS-RV is not the best option for malignant biliopancreatic disorders.

Proposal of an Effective Way of Rescuing People from a Cable Car

This study presents a proposal for procedures and recommendations for the evacuation of people from cable cars. The proposals and procedures were carried out in a specific facility located in the east of Slovakia. Cable cars represent a certain risk of endangering the lives and health of people. This threat can be caused by technical failures, meteorological conditions, or human factors. Despite the existing safety measures, which are at a high level today, extraordinary events occur on cable cars that require the intervention of the integrated rescue system. The rescue services themselves have their own specific rescue procedures and equipment for rescuing people from heights, and in this paper the most frequently used rescue procedures and methods performed by members of the Fire and Rescue Service will be presented. This paper summarizes individual rescue actions, activities, and technical equipment used in rescuing people from cable cars, as well as an analysis of individual rescue and evacuation techniques from the Skipark Erika cable car. The result of the contribution is a proposal for coordination and an evaluation of the best and most suitable method of rescue in terms of time and safety.

Puncture angle on an endoscopic ultrasound image is independently associated with unsuccessful guidewire manipulation of endoscopic ultrasound-guided hepaticogastrostomy: a retrospective study in Japan.

Although endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is performed globally, the procedure remains challenging. Guidewire manipulation is the most difficult step, and there are few reports on the factors associated with unsuccessful guidewire manipulation. This study aimed to assess the significance of the puncture angle on EUS images and identify the most effective guidewire rescue method for patients with unsuccessful guidewire manipulation. We retrospectively enrolled 115 patients who underwent EUS-HGS between May 2016 and April 2022 at two centers. The puncture angle between the needle and the intrahepatic bile duct was measured through EUS movie records. Guidewire manipulation was unsuccessful in 28 patients. Receiver operating characteristic (ROC) curves identified an optimal puncture angle cutoff value of 85° (cutoff value, 85°; area under the ROC curve, 0.826; sensitivity, 85.7%; specificity, 81.6%). Multivariate analysis demonstrated that a puncture angle <85° was a significant risk factor for unsuccessful guidewire manipulation (odds ratio, 19.8; 95% confidence interval, 6.42-61.5; p<0.001). Among the 28 unsuccessful cases, 24 patients (85.7%) achieved successful guidewire manipulation using various rescue methods. The puncture angle observed on EUS is crucial for guidewire manipulation. A puncture angle of <85° was associated with unsuccessful guidewire manipulation.

Genetic Algorithm-based Optimization Model for Emergency Shelters Location Allocation in Public Health Emergency Situations

Deploying emergency resources after a disaster is crucial for reducing the event’s impact. A multi-objective (MO) resource allocation (RA) method is developed to achieve efficient distribution of relief items and the best choice of transportation routes, taking into account the variable and persistent nature of rescue operations. The MO Cellular Genetical Approach (MOC-GA) addresses the concept by incorporating auxiliary populations and neighborhood architecture into the cellular automaton. The comparative experiment conclusively demonstrates that MOC-GA performs favorably compared to Particle Swarm Optimisation (PSO), Ant Colony Optimisation (ACO), and Dragon Fly Optimisation (DFO) in several metrics such as the Pareto Front (PF), hypervolume, mean objective function value, and PF ratios. The findings demonstrate that MOC-GA effectively addresses the MO dynamical emergency RA approach, offering decision-makers a more comprehensive range of superior and diversified candidate rescue strategies than alternative methods. This research analyzes the existing rescue methods and proposes a theoretical rescue strategy to aid decision-makers in making scientifically informed decisions.

An Optimized Site Selection Method for Human-Life Search and Rescue in Inland Waters

An Optimized Site Selection Method for Human-Life Search and Rescue in Inland Waters

An Analysis of the Time Travel Device for Exploring Black-White Race Relations in Octavia E. Butler’s Kindred

The thesis focuses on Octavia E. Butler’s novel Kindred and employs close reading and textual analysis to explore the depiction of black-white race relations through the time travel device. It points out that Butler cleverly uses the method of temporal rescue to break the “grandmother paradox.” The dual-time setting allows Dana, while saving her white ancestors, to witness the harsh realities faced by her African American ancestors in American history. On this basis, the thesis reveals and critiques the historical roots of racial issues, highlighting the physiological and psychological experiences of racial injustice endured by African Americans, as well as the persistence and improvement of the legacy of slavery. It emphasizes the importance of African Americans confronting history to break the cycle of oppression and shape a more equitable future.

A Comparative Study of Transpancreatic Sphincterotomy, Double Guidewire Technique, and Precut Sphincterotomy in Difficult Naive Biliary Cannulations in a Tertiary Care Center in Western India

Abstract Introduction Difficult biliary cannulation leads to prolonged papillary manipulation and repeated attempts at cannulation are known to increase the risk of postendoscopic retrograde cholangiopancreatography (ERCP) pancreatitis. This study aims to compare the efficacy and complications of three rescue methods, transpancreatic biliary sphincterotomy (TP), double guidewire technique (DGW), and precut sphincterotomy (precut) in difficult common bile duct (CBD) cannulations. Methods Seventy-six patients (&gt;18 years of age) with a native papilla undergoing ERCP for biliary cannulation were recruited. Those who had inadvertent pancreatic duct cannulations (&gt;1) were included. A pancreatic stent was inserted in all cases. They underwent either DGW (n = 25), precut (n = 25), or TP (n = 26) as rescue methods and were compared in terms of the success of cannulation and post-ERCP complications. Results Of the total 76 cases, 82% were for benign indications, the most common being choledocholithiasis (69.7%). Jaundice was noted in 52% (n = 13/25), 60% (n = 15/25), and 38.5% (n = 10/26) of the DGW, precut, and TP cases, while 40% (n = 10/25), 12% (n = 3/25), and 30.8% (n = 8/26), respectively, were in cholangitis at presentation. The most common type of papilla was type 1 overall and each subgroup. While successful cannulation was achieved in 88.5% (n = 23/26) of TP and 84% (n = 21/25) of the DGW group, only 64% (n = 16/25) of the precut cases were cannulated. Three (n = 3/25) cases had mild bleeding and two mild pancreatitis, one severe pancreatitis, and one perforation were recorded in the precut group. One patient each had severe and mild pancreatitis in the DGW group, while one had mild pancreatitis and two had moderate pancreatitis in the TP group. All the patients were managed conservatively. Conclusion There was no significant difference in the technical success rate (p = 0.075) as well as complications (p = 0.117) between the three salvage methods for difficult naive CBD cannulations.

Structuring and Recommendations for Research on the Construction of Intelligent Multi-Industry and Multihazard Emergency Planning Systems

During production and operation, enterprises are faced with occurrences of production accidents. One of the prerequisites for enterprises to achieve sustainable development is building an intelligent emergency command platform. To establish a scientific and advanced emergency management information system and address the challenges related to managing emergency plans to ensure production safety, such as ambiguous roles and responsibilities, inefficient application processes, independent resources, and slow responses by enterprises with multiple types of operations and disasters, an intelligent emergency command platform was built for multiple types of operations and disasters, and this platform was extended to include rescue steps. The structure and digital management of emergency plans under multiple coupled disasters and multipoint cogeneration were determined. Similar emergency plans were automatically recommended by crawler technology and an SVM algorithm based on a public information data lake, and the effectiveness of the plans was evaluated via a fuzzy analytic hierarchy process to promote the preparation of more efficient and scientific emergency plans. Finally, the analysis of pipeline leakage and emergency drill scenarios proved that the system is scientific and reliable. The results are of great significance for improving the deep integration of modern emergency-related information technology and emergency management businesses, promoting institutional and mechanical innovation, to provide a reference for other multibusiness enterprises, wchih can also be integrated into methods for urban safety and rescue.

Comparative Analysis of Treatment Strategies for Postoperative Pulmonary Hypertensive Crisis in Congenital Heart Disease

Background: Pulmonary hypertensive crisis (PHC) is a serious life-threatening complication in children with congenital heart disease (CHD) after surgery, with acute onset and high mortality. However, there is still no effective means to deal with this complication. Therefore, our department developed the left atrium and right ventricle duct bridging technique to treat children with PHC, and compare its effects with conventional methods of treatment to determine the best solution for dealing with this complication. Methods: A retrospective analysis of 41 children with CHD surgery and postoperative PHC in our hospital from January 2015 to December 2022 was performed. According to the rescue method, the group with conventional therapy combined with left atrium to right ventricle duct bridging treatment vs. simple conventional therapy were defined as group A and group B respectively, with 13 cases and 28 cases in each group. The success rate of rescue, the complication rate, the length of intensive care unit stay, the delayed chest closure duration, the duration of PHC, the ratio of pulmonary circulation/systemic circulation pressure, the oxygenation index and the cardiac index at 30 min, 1 h, 2 h, 4 h and 6 h after rescue were compared between the two groups. Results: There was a higher success rate of rescue (84.62% vs. 68.86%; p &gt; 0.05), lower complication rate (15.38% vs. 21.43%; p &gt; 0.05), shorter duration of PHC (6.77 ± 2.13 min vs. 13.07 ± 4.05 min; p = 0.000), shorter duration of delayed sternal closure (32.23 ± 5.46 h vs. 38.14 ± 8.61 h; p = 0.029) and shorter length of ICU stay (81.69 ± 8.31 h vs. 93.57 ± 16.84 h; p = 0.021) in group A; After the rescue, the pulmonary artery pressure and cardiopulmonary function recovery rate in group A were faster than those in group B. Conclusions: In conclusion, left atrial to right ventricular duct bridging therapy is more effective in the treatment of PHC after surgery for CHD.

Material Testing of Historic Bricks and Mortars in Degraded Masonry Structures.

The subject of this article is material research carried out on the ruins of a medieval castle located in west-central Poland. This facility was built at the beginning of the 15th century by the Order of St. John, and during its long life, it was subjected to many reconstructions. Unfortunately, in 1975, it was destroyed by fire. Since then, it has been left in a state of advanced ruin, exposed to climatic influences without any protection. The subject of the research was to assess the possibility of maintaining such buildings in a severely degraded condition while ensuring their technical efficiency. The article discusses a particular instance of "consolidation" applied to a structure in a state of historical, architectural, and structural ruin. After the diagnosis, it was determined that the structure should be safeguarded using a minimally invasive method. The purpose of these activities was to answer the question of whether the structure could be left to continue operating despite failing to meet the requirements of current standards and regulations while posing an additional danger to itself and the environment,. This goal was achieved by obtaining a considerable amount of data on the condition of the materials embedded in the masonry structure, thanks to which the initial parameters for conducting an assessment of the technical condition of the damaged masonry structure and evaluating the degree of its danger were developed. The results of the research and analysis carried out and described in this article can be used in other similar situations where saving national heritage objects through "artificial modern" strengthening will be unsafe and will lead to a loss of their authenticity. We still have a long way to go to develop a comprehensive method for "in situ" diagnosis of heterogeneous masonry structures, so we should use possible techniques and knowledge to conduct such assessments and propose rescue methods for historically valuable objects in a way that could minimize the damage and that can "easily" disappear from our surroundings. Each study should have a specific purpose, not only research but also a long-term perspective, making it possible to leave material for further research and analysis, including testing new research methods in real conditions of its installation.

Resynthesizing Brassica napus with race specific resistance genes and race non-specific QTLs to multiple races of Plasmodiophora brassicae

Clubroot disease in canola (Brassica napus) continues to spread across the Canadian prairies. Growing resistant cultivars is considered the most economical means of controlling the disease. However, sources of resistance to clubroot in B. napus are very limited. In this study, we conducted interspecific crosses using a B. rapa line (T19) carrying race-specific resistance genes and two B. oleracea lines, ECD11 and JL04, carrying race non-specific QTLs. Employing embryo rescue and conventional breeding methods, we successfully resynthesized a total of eight B. napus lines, with four derived from T19 × ECD11 and four from T19 × JL04. Additionally, four semi-resynthesized lines were developed through crosses with a canola line (DH16516). Testing for resistance to eight significant races of Plasmodiophora brassicae was conducted on seven resynthesized lines and four semi-resynthesized lines. All lines exhibited high resistance to the strains. Confirmation of the presence of clubroot resistance genes/QTLs was performed in the resynthesized lines using SNP markers linked to race-specific genes in T19 and race non-specific QTLs in ECD11. The developed B. napus germplasms containing clubroot resistance are highly valuable for the development of canola cultivars resistant to clubroot.

Maritime distress target detection algorithm based on YOLOv5s‐EFOE network

AbstractTraditional maritime search and rescue methods mainly rely on manual operation, which takes a long time to identify and results in poor search and rescue results. This paper applies computer vision technology to the field of maritime distress object detection and proposes an improved object detection algorithm YOLOv5s‐EFOE based on the YOLOv5s algorithm. Firstly, the authors change the detection head of the YOLOv5s algorithm to use a mixed channel strategy to build a more efficient decoupling head, reducing the number of 3 × 3 convolutional layers in the middle of the decoupling head to only one. The width of the head is scaled by the width multipliers of Backbone and Neck. Secondly, in conjunction with the SimOTA matching algorithm, the positive samples of the target to be tested are dynamically allocated to improve the recognition ability of different targets. Finally, considering the low pixel value of the maritime distress target from the perspective of unmanned aerial vehicles (UAV), the loss function CIoU in the original YOLOv5s is changed to EIoU. EIoU not only considers the distance and aspect ratio of the centre point, but also considers the true difference between the width and height of the prediction box and the real box, which improves the prediction accuracy of the anchor box. Experiments are conducted on a subset of the public dataset SeaDronesSee. The of the YOLOv5s‐EFOE model proposed in this paper reached 75.9%, reached 79.9%, and reached 44.5%. These indicators are superior to the original YOLOv5s model, YOLOv7 series models, and YOLOv8 series models. Compared with the original model, the YOLOv5s‐EFOE model has increased the by 5.4%, by 5.6%, and by 4.6%, improving the difficult to detect and missed detection situations. This model can be deployed on UAVs and can effectively identify maritime distress target, achieving the purpose of search and rescue.

Firefighters’ behavior via vertical shafts in natural-ventilated tunnels

Tunnel load traffic flows day and night, and is highly susceptible to catching tunnel fires. When a tunnel is on fire, occupants are endangered by the rapid deterioration of the tunnel environment during burning, and their self-evacuation is limited by their unfamiliarity with tunnels. Therefore, efficient and effective firefighting and rescue methods are urgently required to guarantee the safety of occupants during tunnel fires. During firefighting, one of the most important issues is that a fire brigade may encounter difficulties identifying the fire source. They have to deal with congestion and navigate cars piling into the tunnel, which wastes significant time. Therefore, this study provides an alternative approach for firefighters to access fire sources in naturally ventilated tunnels equipped with vertical shafts. This study explored three routes for firefighters from the ground to a fire source in a tunnel. The duration and speed of taking the three routes, along with the use of facilities, firefighters’ communication, and emotions, were presented and analyzed. This indicates that firefighting and rescue via vertical shafts is a feasible and optimized method for naturally ventilated tunnels because the estimated duration decreased by 56.2% (without smoke) and 60.0% (with smoke) compared to traditional routes when the minimum distance from the fire to the nearest exit is 2000 m. In addition, the study provides field experimental data on vertical firefighting in tunnels, which are expected to be used to build and calibrate models for firefighters in future studies.

Effectiveness of Strategy-Focused Training in Colorectal Endoscopic Submucosal Dissection: A Retrospective Observational Study.

Colorectal ESD, an advanced minimally invasive treatment, presents technical challenges, with globally varying training methods. We analyzed the learning curve of ESD training, emphasizing preoperative strategies, notably gravity traction, to guide ESD instructors and trainee programs. This retrospective study included 881 cases guided by an experienced supervisor. Six trainees received "strategy-focused" instruction. To evaluate the number of ESD experiences in steps, the following phases were classified based on ESD experiences of each trainees: Phase 0 (0-50 ESD), Phase 1 (51-100 ESD), Phase 2 (101-150 ESD), and Phase 3 (151-200 ESD). Lesion background, outcomes, and safety were compared across phases. Factors contributing to technical difficulty in early (Phase 0 and 1) and late phases (Phase 2 and 3) were identified, along with the utility of traction ESD with device assistance. Treatment outcomes were favorable, with 99.8% and 94.7% en bloc resection and curative resection rates, respectively. Approximately 90% self-completion rate could be achieved after experiencing about 50 cases (92.7% in Phase 1), signifying proficiency growth despite increased case difficulty. In early phases, factors such as left-sided colon, LST-NG morphology, and severe fibrosis pose challenges. In late phases, LST-NG morphology, mild and severe fibrosis remained significant. Traction-assisted ESD, utilized in 3% of cases, comprised planned (1.1%) and rescue (1.9%) methods. Planned traction aided specific lesions, while rescue traction was common in the right colon. "Strategy-focused" ESD training consistently yields successful outcomes, effectively adapting to varying difficulty factors in different proficient stages.

Bilateral Uterine Artery Embolization as a Rescue Method in a Rare Case of Cervical Ectopic Pregnancy

AbstractCervical pregnancy, being the second rarest form of ectopic pregnancy after abdominal pregnancy, is a difficult clinical entity to diagnose and manage in a young primigravida with no identifiable risk factors or associated symptoms. Further, early intervention is of utmost importance owing to the deleterious complications and high mortality associated with it if not addressed to. It is also difficult to choose a particular management approach for this out of the available options. We report a case of 23-year-old primigravida with 8 weeks of gestation, asymptomatic and with no underlying risk factors, diagnosed with cervical pregnancy during a routine antenatal scan. She was successfully managed with bilateral uterine artery embolization in conjunction with systemic methotrexate followed by suction and evacuation.

Emergency airway management in the prone position: an observational mannequin-based simulation study

IntroductionAccidental extubation during prone position can be a life-threatening emergency requiring rapid establishment of the airway. However, there is limited evidence of the best airway rescue method for this potentially catastrophic emergency. The aim of this study was to determine the most effective method to recover the airway in case of accidental extubation during prone positioning by comparing three techniques (supraglottic airway, video laryngoscopy, and fiber-optic bronchoscopy) in a simulated environment.MethodsEleven anesthesiologists and 12 anesthesia fellows performed the simulated airway management using 3 different techniques on a mannequin positioned prone in head pins. Time required for definitive airway management and the success rates were measured.ResultsThe success rates of airway rescue were 100% with the supraglottic airway device (SAD), 69.6% with the video laryngoscope (CMAC), and 91.3% with the FOB. The mean (SD) time to insertion was 18.1 (4.8) s for the supraglottic airway, 78.3 (32.0) s for the CMAC, and 57.3 (24.6) s for the FOB. There were significant differences in the time required for definitive airway management between the SAD and FOB (t = 5.79, p < 0.001, 95% CI = 25.92–52.38), the SAD and CMAC (t = 8.90, p < 0.001, 95% CI = 46.93–73.40), and the FOB and CMAC (t = 3.11, p = 0.003, 95% CI = 7.78–34.25).ConclusionThe results of this simulation-based study suggest that the SAD I-gel is the best technique to manage accidental extubation during prone position by establishing a temporary airway with excellent success rate and shorter procedure time. When comparing techniques for securing a definitive airway, the FOB was more successful than the CMAC.

Growth, vegetative rescue and vegetative propagation in Eucalyptus species and hybrids

The objective of the study was the evaluation of survival and productivity indicators in different species/hybrids of Eucalyptus in the adult stage, as well as the vegetative rescue of adult trees and cuttings, testing for species/hybrids, concentration of growth regulator and substrates in rooting. In the evaluation of species/hybrids, height (m), diameter at breast height (DBH, cm) and individual volume (m3 per individual) were measured, and survival was evaluated. In the vegetative rescue treatment, the number of shoots produced at 90, 120 and 210 days was evaluated. In the cutting experiments, the species that produced rescue shoots were tested, in addition to indole-3-butyric acid (IBA) doses (0, 1 500, 3 000 and 4 500 mg L−1) and four substrates for rooting cuttings. The experiments of IBA doses and substrates were carried out using Eucalyptus saligna plants. In the cutting experiments, after 120 days of cultivation, the following variables were evaluated: callus formation (%), survival (%), rooting (%), number and length of roots. The best results regarding survival and quantitative variables of the species/hybrids were obtained for E. dunnii, E. dunnii × E. grandis and E. pellita. In the vegetative rescue, E. dunnii × E. grandis and E. pellita had the highest formation of shoots and the girdling vegetative rescue method had the best results in terms of generated shoots. E. saligna had better results regarding the variables related to the rooting of cuttings. The substrate S3 and the use of 1 500 mg L−1 of IBA provided the highest survival rate and better variables related to the rooting of the cuttings.

Underwater Rescue Target Detection Based on Acoustic Images.

In order to effectively respond to floods and water emergencies that result in the drowning of missing persons, timely and effective search and rescue is a very critical step in underwater rescue. Due to the complex underwater environment and low visibility, unmanned underwater vehicles (UUVs) with sonar are more efficient than traditional manual search and rescue methods to conduct active searches using deep learning algorithms. In this paper, we constructed a sound-based rescue target dataset that encompasses both the source and target domains using deep transfer learning techniques. For the underwater acoustic rescue target detection of small targets, which lack image feature accuracy, this paper proposes a two-branch convolution module and improves the YOLOv5s algorithm model to design an acoustic rescue small target detection algorithm model. For an underwater rescue target dataset based on acoustic images with a small sample acoustic dataset, a direct fine-tuning using optical image pre-training lacks cross-domain adaptability due to the different statistical properties of optical and acoustic images. This paper therefore proposes a heterogeneous information hierarchical migration learning method. For the false detection of acoustic rescue targets in a complex underwater background, the network layer is frozen during the hierarchical migration of heterogeneous information to improve the detection accuracy. In addition, in order to be more applicable to the embedded devices carried by underwater UAVs, an underwater acoustic rescue target detection algorithm based on ShuffleNetv2 is proposed to improve the two-branch convolutional module and the backbone network of YOLOv5s algorithm, and to create a lightweight model based on hierarchical migration of heterogeneous information. Through extensive comparative experiments conducted on various acoustic images, we have thoroughly validated the feasibility and effectiveness of our method. Our approach has demonstrated state-of-the-art performance in underwater search and rescue target detection tasks.

Over-the-scope clip rescue method of endoscopic hemostasis for severe acute colonic diverticular bleeding.

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