Air Leak Research Articles

TransitionalHemodynamicsinNeonatesBornThrough Meconium-Stained Amniotic Fluid: A Prospective Observational Study.

Neonates born through meconium-stained amniotic fluid (MSAF) are at increased risk of altered cardiopulmonary transition at birth. There is a paucity of literature evaluating the transitional hemodynamics in these neonates. We aimed to evaluate transitional hemodynamics via echocardiography in neonates born through MSAF, compared to healthy neonates. The primary objective was to assess pulmonary vascular resistance using left pulmonary artery-velocity time integral (LPA-VTI). The secondary objectives were to assess other pulmonary vascular parameters and myocardial function. We enrolled 35 MSAF-born and 35 healthy neonates. Echocardiography was performed at 24 and 48h of life by a pediatric cardiologist. Echocardiographic parameters were compared between MSAF-born and healthy neonates, and between MSAF-born neonates who developed meconium aspiration syndrome (MAS) and who did not (non-MAS). Among 35 MSAF-born neonates, 14 (40%) were non-vigorous, 18 (51%) required admission to neonatal intensive care unit, 8 (23%) developed MAS, 3 (9%) pulmonary hypertension and 1 (3%) air leak. On echocardiography, LPA-VTI (cm;mean ± SD) was significantly decreased at 24 and 48h in MSAF-born neonates (14.38 ± 2.48; 15.55 ± 2.48), compared to healthy neonates (16.60 ± 2.14; 17.66 ± 2.71), respectively. Further, LPA-VTI was significantly reduced at 24 and 48h among MAS (11.81 ± 3.0; 12.43 ± 2.5), compared to non-MAS neonates (15.15 ± 1.72; 16.48 ± 1.55), respectively. Other pulmonary vascular and myocardial function parameters were comparable between the two groups. Pulmonary adaptation was significantly delayed in neonates with MSAF, which was more pronounced in MAS neonates. Further studies should explore the utility of these parameters for early prediction of cardiorespiratory morbidities in this population.

Use of Densitometric Indicators Free DICOM-Viewer’s and Digital Data Processing Programs in Surgical Treatment of Patients with Pulmonary Tuberculosis

Objective — to determine the potential of using freely distributed specialised digital data processing programs and free DICOM-viewers for assessing densitometric indicators obtained from computed tomogra­phy of the thoracic organs. This aims to facilitate the planning of surgical treatment for patients with pulmonary tuberculosis and to substantiate methods for preventing pulmonary-pleural complications. Materials and methods. A retrospective analysis was conducted on the examination and treatment results of 103 patients with specific tuberculous lesions of the lungs. Histological examination of the resected material determined the degree of the specific inflammatory process in the affected tissue, based on which patients were categorised into groups. Group I included 32 patients with low activity of the specific inflammatory process, Group II comprised 37 patients with moderate activity and Group III included 34 patients with high activity. Using five common digital processing programs, densitometric indicators of the thoracic organs' structures were obtained. The accuracy of density indicators displayed by these programs was analysed in comparison with the results of histological examinations. Results and discussion. According to our data, the densitometric indicators obtained using free DICOM-viewers and digital data processing programs show a strong correlation with the reference standard and among themselves. The determined density indicators have a strong association with histological findings of emphysema and fibrosis of the lung parenchyma. These indicators are reliably identified both in cases of high activity of specific inflammation in the lung parenchyma and in inactive processes, allowing for patient stratification. It was found that the average density values of the mediastinal lymph nodes in cases of inactive specific inflammatory processes in 80 % of cases were (54.4 ± 17.8) HU. Values of (15.0 ± 2.5) HU characteri­sed high activity of specific inflammatory processes and the progressive phase of the disease. Clinically, 89 (86.4 %) of the patients with significant deviations in the densitometric density indicators of the lung parenchyma from the norm experienced prolonged air leakage in the postoperative period. In 96 (93.2 %) patients with altered density of mediastinal lymph nodes, prolonged postoperative exudation through pleural drains was noted. Patients with altered densitometric indicators had complicated intraoperative and postoperative courses. Changes in the density of the lung parenchyma detected on computed tomography of the thoracic organs were confirmed in 96.1 % of cases by histological examination of the resected material. These changes were reliably detected by all the programs studied. Conclusions. Densitometric indicators obtained using DICOM-viewers and digital data processing programs enable the planning of surgical treatment for patients with pulmonary tuberculosis and the reasoned application of methods to prevent pulmonary-pleural complications.

Analysis of the influence of uneveneity of the sintering process of the barch on the operation of the sintering machine

Literature data on the unevenness of temperature and composition of the gas leaving the sintering bed across the width and length of it and their influence on the productivity of sinter machines are considered. An analysis of the technologies reasons for the unevenness of the sintering process was carried out. It is shown that the reasons for the width of the pallets include the distribution of the mix bed in the loading bin, air leaks into the ignition hearth, the wall effect at the side plates of the pallets, the shape and angle of inclination of the sides relative to the grates. Along the length of the sinter machine, the unevenness of gas flow and composition is due to a decrease in the gas-dynamic re-sistance of the bed during the sintering process, segregation of the mix and fuel along the height of the bed, completion of bed drying and gaps between pallets. Using an adapted mathematical model of the sintering process, a comparison was made of the parameters of the basic (non-uniform) and calculated uniform operating modes of the AKM-312 sinter machine of the Steel Plant NLMK. I It has been established that with the vertical installation of the pallet sides accepted in the calculations that an increased gas flow rate at the periphery of the bed is accompanied by an increase in gas temperature with a corresponding decrease in the suction before exhausters. It was found that during the transition from the base to the uniform mode of operation of the sinter machine, the gas temperature in front of the exhausters decreased from 99.6 to 85.1 °C, the suction increased from 13.54 to 14.26 kPa, and in the collecting collector – by 1.15 kPa. The productivity of the sinter machine increased by 4.1%. When installing pallet sides vertically, the effectiveness of increasing the height of the layer on its periphery instead of compacting it and constructive solutions has been justified. Its increase provided an additional productivity of the sinter machine by 1.8%, a total of 5.9%. It has been shown that due to the simultaneous increase in gas temperature over the entire width of the bed in the final period of the sintering process, with a uniform operating mode of the sinter machine, the maximum gas temperature at the end of the process increases with a lower one – in front of the exhausters. From the point of view of the capabilities of exhausters in terms of the created suction, the accepted representation of their gas-dynamic characteristics at a temperature of 150 °C, which is possible only with a high level of unevenness of the sintering process, is not reasoned

Treatment approach in bilateral pulmonary hydatid cysts: analysis of 107 consecutive cases.

Bilateral pulmonary involvement is observed in around 14% of cases of pulmonary hydatid cysts and the treatment can be challenging. This study evaluates the clinical characteristics and treatment strategies used for cases of bilateral pulmonary hydatid cysts. A retrospective examination was conducted on 107 consecutive cases of bilateral pulmonary hydatid cysts treated in our clinic between January 2003 and December 2023. Out of the 107 cases analyzed, 57 (53.3%) were male and 50 (46.7%) were female. Surgical intervention was performed for pulmonary hydatid cysts in 92 cases (86.0%), while medical treatment was prescribed for the remaining 15 cases (14.0%). Bilateral thoracotomies were consecutively conducted in 77 cases; in 11 cases, thoracotomy was carried out on one side and contralateral hydatid cysts were treated medically. Three cases underwent sternotomy, and one underwent bilateral thoracotomy during a single session. One case experienced postoperative hemorrhage, three cases had prolonged air leakage, two cases had empyema, one case had a wound infection, and one case had a recurrence of hydatid cyst. For bilaterally operated cases, albendazole treatment commenced after the second operation and was carried out in two 15-day cycles. Patients who declined, or were not eligible for surgery, were treated with albendazole for an extended period. Consecutive bilateral thoracotomy, followed by two cycles of albendazole therapy, is a highly effective treatment for patients with bilateral pulmonary hydatid cysts. In cases with widespread involvement, ruptured small cysts, or serious comorbidities, long-term medical treatment including albendazole administration may be applied.

Effects on environmental conditions and limiting parameters for spontaneous combustion of residual coal in underground goaf

This study collected coal from the Meihuajing Coal Mine, Ningxia, China, and employed a temperature-programmed experimental setup to investigate the characteristics of coal spontaneous combustion (CSC) and determine the primary parameters influencing coal temperature in the goaf of this underground mine. The obtained results indicated that positive correlations existed between CO concentration, CO2 concentration, oxygen consumption rate, exothermic intensity, and coal temperature. Principal component analysis (PCA) was employed to examine the correlations of three limiting parameters—namely maximum air leakage intensity (Qmax), minimum oxygen volume fraction (Cmin), and minimum thickness of residual coal (Hmin)—with coal temperature (30–170 °C) during coal oxidation. The results of a PCA indicated that among these parameters, Qmax was most strongly correlated with coal temperature. In addition, gray correlation analysis (GCA) was adopted to examine the primary parameters influencing the occurrence of CSC during different stages. The results of GCA indicated that the primary parameter influencing the occurrence of CSC varied with the coal oxidation stage. At coal temperatures between 80 and 90 °C, Cmin and Hmin were the primary parameters influencing coal temperature. The correlation curves of Cmin and Hmin with respect to coal temperature fit well with the GaussMod model. The findings of this research provide a theoretical foundation for mitigating CSC in underground goafs.

Air-Leak-Management Supported by Ventilation-SPECT/CT: A New Perspective on a Long-Known Problem

Abstract Background Prolonged air leakage (PAL) is a common problem after lung surgery. Localization of air leaks (AL) remains challenging in some cases especially in minimally invasive surgery. Ventilation-SPECT/Computertomography (vSPECT/CT) has been reported as potential aid to identify and localize AL. Aims To evaluate vSPECT/CT as potential aid for the localization of AL and explore its use as support for PAL management. Methods Retrospective analysis of a case series of seven patients with PAL after minimally invasive thoracic surgery at our institution in 2023 for which vSPECT/CT was applied. Results Six patients underwent oncologic lung resections, one patient underwent thymectomy for a thymoma. In 5/7 cases an AL was spotted with vSPECT/CT (maximal AL ranged from 40-2000 ml/min). In the remaining two cases (with a maximal AL of 1900ml/min for 1 day, and 10 ml/min after more than 4 weeks and continuous clinical signs of PAL), the AL could neither be localized during revision surgery. Nevertheless, the AL ceased in all patients after revision surgery. In two cases the detected AL supported the continuance of conservative treatment as it confirmed a leak within the prior resection site (maximal AL 40ml/min and 200ml/min). These results are depicted in the attached visual abstract. Conclusion The use of vSPECT/CT for localizing ALs proved to be precise in all instances where an imaging spot was observed (5/5 cases). Additionally, in the two cases where no spot was detected, no AL was found during subsequent revision surgery. These initial results are promising and support further prospective studies of a broader group of cases, reinforcing the role of vSPECT/CT as valuable aid in managing PAL.

Risk Factors for Prolonged Air Leakage after Uniportal Anatomical Segmentectomy

Abstract Background As the population ages and comorbidities increase, minimal invasive anatomical segmentectomies are increasingly being performed. Complications are to be considered in this vulnerable population. Aims Our aim was to investigate the incidence and risk factors for prolonged air leak in patients undergoing minimally invasive single-port pulmonary segmentectomy at our institution. Methods Retrospective analysis of all patients undergoing uniportal segmentectomy in our department from March 2015 to August 2023. Prolonged air leak (PAL) was defined as an air leak that lasted longer than 5 days. Results 575 segmentectomies were performed using uniportal video-assisted thoracoscopic surgery (uVATS). 374 complex segmentectomies (65.0%) and 405 (70.4%) single segmentectomies were performed. Prolonged air leak occurred in 88 patients (15.3%). Length of stay and duration of drainage were 8.6 (±4.86) and 10.6 (±8.12) days in the PAL subgroup, whereas they wer 3.6 (±2.25) and 2.0 (±1.3) days in the non-PAL group, both statistically significant. Patients with COPD GOLD II/III were significantly more common in the PAL group. Using machine learning, two models were developed that predicted the occurrence of PAL with an accuracy of 70 %. The first model detected the following parameters as significant: removal of segment 2 or 8, diabetes, inhalers, squamous cell carcinoma. The second model recognized DLCO (%), pack-years, FEV1 (%) and operation time as parameters. Furthermore, we used recursive partitioning to develop a decision tree that stratified PAL risk by answering 1-3 yes/no questions. Patients with >28 pack-years and DLCO < 71% had a 77% probability of developing prolonged air leak. Conclusion Severe COPD, low DLCO and FEV1, increased pack-years, inhalers, diabetes, and segment 2 or 8 surgery were identified as risk factors for prolonged air leak. These findings may help in the planning of surgery and the use of sealants at the end of surgery in high-risk patients.

Dual-color FISH analyses of xenogeneic human fibroblast sheets transplanted to repair lung pleural defects in an immunocompromised rat model

BackgroundPulmonary air leaks (PALs) due to visceral pleura injury during surgery is frequently observed after pulmonary resections and the complication is difficult to avoid in thoracic surgery. The development of postoperative PALs is the most common cause of prolonged hospitalization. Previously, we reported that PALs sealants using autologous dermal fibroblast sheets (DFSs) harvested from temperature-responsive culture dishes successfully closed intraoperative PALs during lung resection.ObjectiveIn this study, we investigated the fate of human DFSs xenogenetically transplanted onto lung surfaces to seal PALs of immunocompromised rat. Dual-color FISH analyses of human fibroblast was employed to detect transplantation human cells on the lung surface.ResultsOne month after transplantation, FISH analyses revealed that transplanted human fibroblasts still composed a sheet-structure, and histology also showed that beneath the sheet’s angiogenesis migrating into the sheets was observed from the recipient tissues. FISH analyses revealed that even at 3 months after transplantation, the transplanted human fibroblasts still remained in the sheet. Dual-color FISH analyses of the transplanted human fibroblasts were sparsely present as a result of the cells reaching the end of their lifespan, the cells producing extracellular matrix, and remained inside the cell sheet and did not invade the lungs of the host.ConclusionsDFS-transplanted human fibroblasts showed that they are retained within cell sheets and do not invade the lungs of the host.

Enhancing energy conservation in power generation in a coal fired thermal power plant through comprehensive energy audit

Current work presents salient insights from energy audit of a 1050 MW thermal power plant by BEE Certified Energy Auditors. It provides insights into grassroot level data instead of relying only on theoretical calculations, unlike previously published literature.Arresting the air leakages in air-preheater has given total saving of 10.72 million kWh/year, saved 398,978.97 kJ/year, thus saving of 25,322.80 MT of coal/year. Upgradation of insulation resulted in total saving of 6632.208 Million kJ/year, i.e. saving of 510 MT/year of coal. Replacing cooling tower blades material proposed saving of 15,242.4 kWh/year. Installation of Variable Speed Drives for pumps provided saving of 274,836 kWh/year. Replacement of old inefficient pumps with energy efficient pumps has saving potential of 739,632 kWh/year. Pressure reduction in compressors has given saving of 344,794 kWh/year.Thus, in total, this energy audit helped to conserve 12.098 Million kWh & 25,832.80 MT coal/year and consequently, 104,243 tCO2/year. Such savings not only help the plant management/decision makers on the monetary front but also identify the avenues for improvement and channelize the resources such time and investment, prudently. Consequently, it has been established that energy audit is a pragmatic tool to achieve energy conservation at grassroot level.

ASO Visual Abstract: Complications of Outpatient Chest Tube Management for Prolonged Air Leaks After Pulmonary Surgery.

ASO Visual Abstract: Complications of Outpatient Chest Tube Management for Prolonged Air Leaks After Pulmonary Surgery.

Analysis of distribution method of designed air quantity in coal mine ventilation—a case study

In a coal mine, air leakage exists in some roadways through doors and other ventilation structures inevitably. Based on this opinion, there are different views on whether these roadways must be assigned airflow in coal mine ventilation design. This paper analyses some relevant regulations and criteria on the designed air quantity of coal mines. Then, based on the ventilation design of the Guizhou Yizhong Coal Mine, through the study of the calculation of needed air quantity of every working place and its distribution method in coal mine ventilation design, this paper puts forward that explosion-proof door, safety exit, and other short distance roadways with ventilation structures need not assign airflow in coal mine ventilation design, while some long-distance roadways need. Additionally, it presents the main reason to support this opinion, gives the distribution method of inner air leakage quantity, which comes with the calculation of the designed mine total air quantity, puts forward the remedy method for the air leakage through ventilation structures in a coal mine ventilation system, then offers the mine operator with the basic opinions for the day-to-day planning and effective operation of a coal mine ventilation system.

Advancements in the Management of Postoperative Air Leak following Thoracic Surgery: From Traditional Practices to Innovative Therapies.

Background: Postoperative air leak (PAL) is a frequent and potentially serious complication following thoracic surgery, characterized by the persistent escape of air from the lung into the pleural space. It is associated with extended hospitalizations, increased morbidity, and elevated healthcare costs. Understanding the mechanisms, risk factors, and effective management strategies for PAL is crucial in improving surgical outcomes. Aim: This review seeks to synthesize all known data concerning PAL, including its etiology, risk factors, diagnostic approaches, and the range of available treatments from conservative measures to surgical interventions, with a special focus on the use of autologous plasma. Materials and Methods: A comprehensive literature search of databases such as PubMed, Cochrane Library, and Google Scholar was conducted for studies and reviews published on PAL following thoracic surgery. The selection criteria aimed to include articles that provided insights into the incidence, mechanisms, risk assessment, diagnostic methods, and treatment options for PAL. Special attention was given to studies detailing the use of autologous plasma in managing this complication. Results: PAL is influenced by a variety of patient-related, surgical, and perioperative factors. Diagnosis primarily relies on clinical observation and imaging, with severity assessments guiding management decisions. Conservative treatments, including chest tube management and physiotherapy, serve as the initial approach, while persistent leaks may necessitate surgical intervention. Autologous plasma has emerged as a promising treatment, offering a novel mechanism for enhancing pleural healing and reducing air leak duration, although evidence is still evolving. Conclusions: Effective management of PAL requires a multifaceted approach tailored to the individual patient's needs and the specifics of their condition. Beyond the traditional treatment approaches, innovative treatment modalities offer the potential to improve outcomes for patients experiencing PAL after thoracic surgery. Further research is needed to optimize treatment protocols and integrate new therapies into clinical practice.

A Facile Scalable Strategy for Constructing Novel Robust Self‐Healing Glove Utilizing Nanoreinforced Thermoreversible Carboxylated Nitrile Butadiene Rubber

AbstractRecent decades have seen an increase in using self‐healing technology in fabricating multifunctional rubber materials, which incorporate intrinsic mechanisms. However, achieving commendable self‐healing efficiency while maintaining strength in thin rubber films remains challenging. Herewith, the preparation of self‐healing carboxylated nitrile butadiene rubber thin films is presented with 0.40 ± 0.05 mm thickness, reinforced with sustainable TEMPO‐oxidized cellulose nanofibers. The thin films are fabricated using wet mixing and casting methods and translated to prototype fabrication via dipping. The study involves the effect of varying zinc stearate and filler concentrations on healing efficiency via ionic mechanisms alongside other characterization techniques, such as chemical composition, surface morphology, cross‐link density, and thermal stability. The fabricated thin films exhibited a tensile strength of 5.38 MPa and an elongation‐at‐break of 518%. After undergoing a temperature‐induced healing process at 100 °C for 1 h, the healing efficiency for both properties reached 72% and 90%, respectively. Moreover, these films demonstrates the ability to heal repeatedly at the same fracture site over multiple cycles, maintaining a healing efficiency of over 45% after the third cycle. A glove prototype is fabricated and tested using water and air leakage tests to prove the self‐healing technology's successful transfer.

A New Functional Threshold for Minimally Invasive Lobectomy.

To assess the performance of a lower predicted postoperative (ppo) forced expiratory volume in 1 second (FEV1) or diffusion capacity of the lung for carbon monoxide (DLCO) (ppoFEV1/ppoDLCO) threshold to predict cardiopulmonary complications after minimally invasive surgery (MIS) lobectomy. Although MIS is associated with better postoperative outcomes than open surgery, MIS uses risk-assessment algorithms developed for open surgery. Moreover, several different definitions of cardiopulmonary complications are used for assessment. All patients who underwent MIS lobectomy for clinical stage I-II lung cancer from 2018 to 2022 at our institution were considered. The performance of a ppoFEV1/ppoDLCO threshold of <45% was compared against that of the current guideline threshold of <60%. Three different definitions of cardiopulmonary complications were compared: Society of Thoracic Surgeons (STS), European Society of Thoracic Surgeons (ESTS), and Berry et al. In 946 patients, the ppoFEV1/ppoDLCO threshold of <45% was associated with a higher proportion correctly classified (79% [95% CI, 76%-81%] vs. 65% [95% CI, 62%-68%]; P<0.001). The complication with the biggest difference in incidence between ppoFEV1/ppoDLCO of 45%-60% and >60% was prolonged air leak (33 [13%] vs. 34 [6%]; P<0.001). The predicted probability curves for cardiopulmonary complications were higher for the STS definition than for the ESTS or Berry definitions across ppoFEV1 and ppoDLCO values. The ppoFEV1/ppoDLCO threshold of <45% more accurately classified patients for cardiopulmonary complications after MIS lobectomy, emphasizing the need for updated risk-assessment guidelines for MIS lobectomy to optimize additional cardiopulmonary function evaluation.

Current Advances and Gaps in Knowledge on Personalizing Masks for Noninvasive Respiratory Support.

Noninvasive respiratory support delivered through a face mask has become a cornerstone treatment for adults and children with acute or chronic respiratory failure. However, an imperfect mask fit by using commercially available interfaces is frequently encountered, which may result in patient discomfort and treatment inefficiency or failure. To overcome this challenge, over the past decade, increasing attention has been given to the development of personalized face masks, which are custom-made to address the specific facial dimensions of an individual patient. With this scoping review, we aim to provide a comprehensive overview of the current advances and gaps in knowledge with regard to the personalization masks for CPAP and NIV. We performed a systematic search of the literature and identified and summarized a total of 23 studies. Most studies included were involved in the development of nasal masks. Studies that targeted adult respiratory care mainly focused on chronic (home) ventilation and included some clinical testing in a relevant subject population. In contrast, pediatric studies focused mostly on respiratory support in the acute setting, whereas testing was limited to bench or case studies only. Most studies were positive with regard to the performance (ie, comfort, level of air leak, and mask pressure applied to the skin) of personalized masks in bench testing or in human, healthy or patient, subjects. Advances in the field of 3-dimensional scanning and soft material printing were identified, but important gaps in knowledge remain. In particular, more insight into cushion materials, headgear design, clinical feasibility, and cost-effectiveness is needed before definite recommendations can be made with regard to implementation of large-scale clinical programs that personalize noninvasive respiratory support masks for adults and children.

Twenty four-month follow-up after bullectomy, unilateral and bilateral lung volume reduction surgery: a single-center retrospective analysis of consecutive cases

PurposeWhile pharmacologic therapy remains the cornerstone of lung emphysema treatment, surgery is an additional therapeutic option in selected patient groups with advanced emphysema. The aim of lung volume reduction surgery (LVRS) is to improve lung function, exercise capacity, quality of life and survival. We sought to determine the therapeutic value of surgical resection in specific patients with lung emphysema.Patients and methodsA retrospective study was performed consisting of 58 patients with lung emphysema who underwent surgical intervention over a 10-year period and were followed for 2 years postoperatively. The clinical characteristics recorded were FEV1 (forced expiratory volume in 1 s), the 6-min walk test (6-MWT), the Modified Medical Research Council (mMRC), body mass index (BMI) and quality of life prior to and 6, 12 and 24 months after surgical intervention. Moreover, all peri- and post-operative complications were noted.ResultsOut of 58 emphysema patients (72% male, FEV1 (L) 2.21 ± 0.17, RV (L) 3.39 ± 0.55), 19 underwent surgical bullectomy, 31 unilateral LVRS and 8 sequential bilateral LVRS. Six months after surgery, there was a statistically significant improvement in FEV1, RV, TLC, 6-MWT and mMRC. Over a period of 12 to 24 months postoperatively, clinical benefit gradually declines most likely due to COPD progression but patients still experienced a significant improvement in FEV1. The most common postoperative complications were persistent air leakage (> 7 days), arrhythmia and subcutaneous emphysema in 60%, 51.6% and 22.4%, respectively. No deaths were observed after surgical intervention.ConclusionIn a selected patient population, surgery led to significant improvement of lung function parameters, exercise capacity and quality of life. Over a period of 12 to 24 months postoperatively, clinical benefit gradually decreased most likely due to COPD progression.

Design, fabrication and experiment of soft fingers with double-chamber based on layer jamming

PurposeThe purpose of this paper is to propose a casting process for the production of double-chamber soft fingers, which avoids the problems of air leakage and fracture caused by multistep casting. This proposed method facilitates the simultaneous casting of the inflation chamber and the jamming chamber.Design/methodology/approachAn integrated molding technology based on the lost wax casting method is proposed for the manufacture of double-chamber soft fingers. The solid wax core is assembled with the mold, and then liquid silicone rubber is injected into it. After cooling and solidification, the mold is stripped off and heated in boiling water, so that the solid wax core melts and precipitates, and the integrated soft finger is obtained.FindingsThe performance and fatigue tests of the soft fingers produced by the proposed method have been carried out. The results show that the manufacturing method can significantly improve the fatigue resistance and stability of the soft fingers, while also avoiding the problems such as air leakage and cracking.Originality/valueThe improvement of the previous multistep casting method of soft fingers is proposed, and the integrated molding manufacturing method is proposed to avoid the problems caused by secondary bonding.

Method for expert evaluation of the technical con-dition of the cylinder-piston group of automotive engines after hydrolock

Problem: The study examines the thermogasdynamic process within an internal combustion engine cylinder during cold cranking mode while measuring compression. Analysis of various models and comparison of known data revealed unresolved challenges in constructing mathematical models of the engine operating cycle. The vast majority of practical data and recommendations for compression measurement in a cylinder are based on empirical knowledge, numerous experiments, and tests. Consequently, there arises a need for computational models of the compression measurement process and their theoretical justification, particularly in cases where engine damage occurs during hydrolock in a cylinder. Methodology. To address the identified issues, a mathematical model of the thermogasdynamic process within the cylinder during cold cranking while measuring compression was developed. Originality. Unlike existing models, this model describes the processes in the cylinder step by step, considering the real nature of intake-exhaust processes, air leakage through part interfaces, and heat exchange with the walls. Through modeling, the main patterns of compression changes depending on the modes and the nature of damage to associated parts of the valve mechanism and the cylinder-piston group were identified, including deformation of the connecting rod during hydraulic lock due to liquid entering the cylinder. Practical value. Based on the study results, it was concluded that the model's properties make it effectively applicable in diagnosing and monitoring the technical condition of automotive engines during operation.

Air Leakage Characteristics of Gas Boreholes in Deep Coal Seams and Application of Short-Hole Grouting and Plugging.

Drilling for gas extraction is widely used as the main approach to manage gas in mines. However, gas leakage during borehole extraction reduces the root cause of the effectiveness of gas extraction. Given that forming a normal hole in the prominent coal seam of the Qingdong Coal Mine is impossible and that air leakage leads to difficulties in prepumping gas in the coal seam, we selected coal seam 3# as the object of this study. First, qualitative analysis determined that the air leakage channel restricted effective gas extraction. Second, short-hole grouting and plugging were proposed to increase the concentration and efficiency of gas extraction from the coal wall, forming a barrier by blocking the fissure network in the plastic zone of the surrounding rock of the coal roadway and preventing the air inside the roadway from penetrating into the coal seam and gas extraction drill holes. Finally, evaluation of the gas extraction efficiency between the grouting test and comparison areas indicated that the initial gas extraction concentration of a single hole could reach 89% when the depth of the selected blocking hole was 15 m. Grouting slowly decreased the gas extraction concentration from 72 to 25%, which effectively improved the speed at which the gas content was reduced in the coal body. The study findings provide a field basis for similar mines to improve their gas extraction efficiency and extend their extraction time.

Joint ERS/EACTS/ESTS clinical practice guidelines on adults with spontaneous pneumothorax.

The optimal management for spontaneous pneumothorax (SP) remains contentious, with various proposed approaches. This joint clinical practice guideline from the ERS, EACTS and ESTS societies provides evidence-based recommendations for the management of SP. This multidisciplinary Task Force addressed 12 key clinical questions on the management of pneumothorax, using ERS methodology for guideline development. Systematic searches were performed in MEDLINE and Embase. Evidence was synthesised by conducting meta-analyses, if possible, or narratively. Certainty of evidence was rated with GRADE (Grading, Recommendation, Assessment, Development and Evaluation). The Evidence to Decision framework was used to decide on the direction and strength of the recommendations. The panel makes a conditional recommendation for conservative care of minimally symptomatic patients with primary spontaneous pneumothorax (PSP) who are clinically stable. We make a strong recommendation for needle aspiration over chest tube drain for initial PSP treatment. We make a conditional recommendation for ambulatory management for initial PSP treatment. We make a conditional recommendation for early surgical intervention for the initial treatment of PSP in patients who prioritise recurrence prevention. The panel makes a conditional recommendation for autologous blood patch in secondary SP patients with persistent air leak (PAL). The panel could not make recommendations for other interventions, including bronchial valves, suction, pleurodesis in addition to surgical resection or type of surgical pleurodesis. With this international guideline, the ERS, EACTS and ESTS societies provide clinical practice recommendations for SP management. We highlight evidence gaps for the management of PAL and recurrence prevention, with research recommendations made. This update of an ERS Task Force statement from 2015 provides a concise comprehensive update of the literature base. 24 evidence-based recommendations were made for management of pneumothorax, balancing clinical priorities and patient views.https://bit.ly/3TKGp9e.