In recent years, with the aggravation of population aging and the change of lifestyle, the incidence of various spinal diseases has increased year by year. Surgical treatment can alleviate pain, correct deformity and ...In recent years, with the aggravation of population aging and the change of lifestyle, the incidence of various spinal diseases has increased year by year. Surgical treatment can alleviate pain, correct deformity and reconstruct spinal stability. With the increase of the amount and difficulty of spinal surgery, perioperative bleeding can not be ignored. Excessive bleeding can cause a variety of complications and even affect the prognosis of patients. Reducing bleeding is important not only to maintain the hemodynamic balance of patients, but also to observe the surgical field of vision. Therefore, how to effectively control the amount of intraoperative bleeding has always been the focus of spinal surgeons. It is particularly important to formulate an effective perioperative bleeding management plan. Preoperative operation plan and the use of various hemostatic drugs, materials and equipment have shown good results in safely reducing the amount of bleeding. The application of hemodilution technology and intraoperative autologous blood reinfusion technology also provides a guarantee for reducing the amount of bleeding and allogeneic blood transfusion.展开更多
This paper aims to obtain the thermodynamic characteristics of the air system control device sealing part in different compressor bleed air and ambient temperature.On the basis of considering the main factors affectin...This paper aims to obtain the thermodynamic characteristics of the air system control device sealing part in different compressor bleed air and ambient temperature.On the basis of considering the main factors affecting the heat exchange process and simplifying the physical model of the air system control device,the thermodynamic model of air system control device is established based on the basic theory of laminar flow heat transfer and heat conduction theory.Then the piston motion characteristics and the thermodynamic characteristics of the air system control device seal are simulated.The simulation results show that the valve actuation dynamic time of piston is about 0.13 s in the actual working conditions,and the temperature effect on the dynamic response of the piston rod is only 5 ms when the inlet air temperature at 300 ℃ and 370 ℃.The maximum temperature of the air system control device sealing part is not more than 290 ℃ under long time working condition of compressor air entraining.The highest temperature of the sealing part can reach up to 340 ℃ when the air flow temperature reaches the limit temperature of 370 ℃,and the longest duration working temperature limit is not more than 14 s.Therefore,the selection of control device sealing material should consider the work characteristic of instantaneous temperature limit.展开更多
BACKGROUND Laparoscopic liver resection(LLR)can be challenging due to the difficulty of establishing a retrohepatic tunnel under laparoscopy.Dissecting the third hepatic hilum before parenchymal transection often lead...BACKGROUND Laparoscopic liver resection(LLR)can be challenging due to the difficulty of establishing a retrohepatic tunnel under laparoscopy.Dissecting the third hepatic hilum before parenchymal transection often leads to significant liver mobilization,tumor compression,and bleeding from the short hepatic veins(SHVs).This study introduces a novel technique utilizing the ventral avascular area of the inferior vena cava(IVC),allowing SHVs to be addressed after parenchymal transection,thereby reducing surgical complexity and improving outcomes in in situ LLR.AIM To introduce and evaluate a novel LLR technique using the ventral avascular area of the IVC and compare its short-term outcomes with conventional methods.METHODS The clinical cohort data of patients with pathologically confirmed hepatocellular carcinoma or intrahepatic cholangiocarcinoma who underwent conventional LLR and novel LLR between July 2021 and July 2023 at the First Affiliated Hospital of Chongqing Medical University were retrospectively analyzed.In novel LLR,we initially separated the caudate lobe from the IVC using dissecting forceps along the ventral avascular area of the IVC.Then,we transected the parenchyma of the left and right caudate lobes from the caudal side to the cephalic side using the avascular area as a marker.Subsequently,we addressed the SHVs and finally dissected the root of the right hepatic vein or left hepatic vein.The short-term postoperative outcomes and oncological results of the two approaches were evaluated and compared.RESULTS A total of 256 patients were included,with 150(58.59%)undergoing conventional LLR and 106(41.41%)undergoing novel LLR.The novel technique resulted in significantly larger tumor resections(6.47±2.96 cm vs 4.01±2.33 cm,P<0.001),shorter operative times(199.57±60.37 minutes vs 262.33±83.90 minutes,P<0.001),less intraoperative blood loss(206.92±37.09 mL vs 363.34±131.27 mL,P<0.001),and greater resection volume(345.11±31.40 mL vs 264.38±31.98 mL,P<0.001)compared to conventional LLR.CONCLUSION This novel technique enhances liver resection outcomes by reducing intraoperative complications such as bleeding and tumor compression.It facilitates a safer,in situ removal of complex liver tumors,even in challenging anatomical locations.Compared to conventional methods,this technique offers significant advantages,including reduced operative time,blood loss,and improved overall surgical efficiency.展开更多
Background: Life-threatening bleeding is a major cause of trauma-related deaths. Stop the Bleed—Active bleeding control (ABC) program in Hyderabad recently showed that lay first responders can be effectively trained....Background: Life-threatening bleeding is a major cause of trauma-related deaths. Stop the Bleed—Active bleeding control (ABC) program in Hyderabad recently showed that lay first responders can be effectively trained. However, the willingness of high school students to train in bleeding control is unknown. We report Stop the Bleed training needs assessment from high schools in India and estimate the potential multiplier effect. Methods: A cross-sectional survey was conducted from 12 randomly selected schools in Hyderabad. The study was to understand current knowledge, skills and willingness to get trained and respond to life-threatening bleeding from injuries. 107 Participants (35 Teachers and 72 students) were purposively selected for telephonic interviews with a structured questionnaire. Results: Response rate was 93% overall. 80% of participants have never been trained in bleeding control. 84% reported willingness to be trained, train others and help bleeding victims. All the teachers reported that stop the bleed training would be useful in high schools. 70.6% of teachers recommended that training could start from middle school (10 to 15 years), 47% preferred the online training mode. Only 20% of participants had prior training in lifesaving first aid and 32% did not know the number of emergency medical services (EMS). Each trained participant has the potential to train 3 to 4 people at the household level and perhaps more at the community level. Conclusion: The surveyed schools in Hyderabad do not have the knowledge, skills, or training curriculum in Stop the Bleed. Students and teachers are willing to be trained and train others, with great potential for a “multiplier-effect” in the community.展开更多
Understanding and managing the bleeding＇s causes is essential for a good surgical practice in general. In fact, it is crucial to know how to manage and control this problem （sometimes simply annoying, but that may b...Understanding and managing the bleeding＇s causes is essential for a good surgical practice in general. In fact, it is crucial to know how to manage and control this problem （sometimes simply annoying, but that may be able to cause even dangerous consequences） with a comprehensive and multidisciplinary approach, trying to use all the means is available today. The goal of this paper is to describe, even through a brief review of the literature--the State of Art about the bleeding control in oral surgery, the proper use of surgical devices and the NOACs （new oral anticoagulants） appearance.展开更多
The hysteresis during the throat regulation process of a supersonic variable inlet is unconducive to restart.Hence,detailed experimental studies of such a hysteresis and its control are necessary.A throat variable sup...The hysteresis during the throat regulation process of a supersonic variable inlet is unconducive to restart.Hence,detailed experimental studies of such a hysteresis and its control are necessary.A throat variable supersonic inlet was designed at a shock-on-lip Mach number of 4.0 and an Internal Contraction Ratio(ICR)ranging over 1.21–2.94.Meanwhile,a distributed bleed system was proposed to suppress the hysteresis.The wind tunnel tests were conducted at Mach number 2.9.The throat regulation processes were recorded using a high-speed schlieren and dynamic pressure acquisition system.The results indicate that the unstart and restart ICRs during the uncontrolled inlet’s throat regulation process were 1.95 and 1.48,respectively,demonstrating an unstart-restart hysteresis.Four typical flowfields were summarized during the uncontrolled inlet’s restart process.The proposed bleed control increased the unstart and restart ICRs to 2.06 and 1.75,respectively,and the inlet realized the designed state as the ICR was further decreased to 1.67.The controlled inlet’s hysteresis loop was decreased compared to the uncontrolled inlet.Finally,the mechanism of the hysteresis,dominated by the entrance separation-induced wave system,was clarified.The mechanisms of the bleed control to broaden the unstart and restart boundaries and suppress the hysteresis were elucidated.展开更多
In this contribution a quasi-one-dimensional tool for stationary and transient simulations of post-stall flows in multistage axial compressors is presented. An adapted version of the 1D Euler equations with additional...In this contribution a quasi-one-dimensional tool for stationary and transient simulations of post-stall flows in multistage axial compressors is presented. An adapted version of the 1D Euler equations with additional source terms is discretized with a finite volume method and solved in time by a fourth-order Runge-Kutta scheme. The equations are discretized at midspan both inside the blade rows and the non-bladed regions. The source terms express the blade-flow interactions and are estimated by calculating the velocity triangles for each blade row. Loss and deviation correlations are implemented and compared to experimental data in normal flow, stalled flow and reversed flow regions. Transient simulations are carried out and a parameter study is presented to analyze the shape of the surge cycles and the frequency of the surge oscillations. At last, a bleeding control strategy is implemented to study the recoverability of the instabilities in a compression system.展开更多
文摘In recent years, with the aggravation of population aging and the change of lifestyle, the incidence of various spinal diseases has increased year by year. Surgical treatment can alleviate pain, correct deformity and reconstruct spinal stability. With the increase of the amount and difficulty of spinal surgery, perioperative bleeding can not be ignored. Excessive bleeding can cause a variety of complications and even affect the prognosis of patients. Reducing bleeding is important not only to maintain the hemodynamic balance of patients, but also to observe the surgical field of vision. Therefore, how to effectively control the amount of intraoperative bleeding has always been the focus of spinal surgeons. It is particularly important to formulate an effective perioperative bleeding management plan. Preoperative operation plan and the use of various hemostatic drugs, materials and equipment have shown good results in safely reducing the amount of bleeding. The application of hemodilution technology and intraoperative autologous blood reinfusion technology also provides a guarantee for reducing the amount of bleeding and allogeneic blood transfusion.
基金supported by the National Major Special Projects for Gas Engine and Aero Engine(No.2017-V-0013)the Aviation Funds(No.20150653006)the Fundamental Research Funds for the Central Universities(No.G2017KY0003)
文摘This paper aims to obtain the thermodynamic characteristics of the air system control device sealing part in different compressor bleed air and ambient temperature.On the basis of considering the main factors affecting the heat exchange process and simplifying the physical model of the air system control device,the thermodynamic model of air system control device is established based on the basic theory of laminar flow heat transfer and heat conduction theory.Then the piston motion characteristics and the thermodynamic characteristics of the air system control device seal are simulated.The simulation results show that the valve actuation dynamic time of piston is about 0.13 s in the actual working conditions,and the temperature effect on the dynamic response of the piston rod is only 5 ms when the inlet air temperature at 300 ℃ and 370 ℃.The maximum temperature of the air system control device sealing part is not more than 290 ℃ under long time working condition of compressor air entraining.The highest temperature of the sealing part can reach up to 340 ℃ when the air flow temperature reaches the limit temperature of 370 ℃,and the longest duration working temperature limit is not more than 14 s.Therefore,the selection of control device sealing material should consider the work characteristic of instantaneous temperature limit.
基金Supported by the General Project of the Natural Science Foundation of Chongqing,No.cstc2021jcyj-msxmX0604.
文摘BACKGROUND Laparoscopic liver resection(LLR)can be challenging due to the difficulty of establishing a retrohepatic tunnel under laparoscopy.Dissecting the third hepatic hilum before parenchymal transection often leads to significant liver mobilization,tumor compression,and bleeding from the short hepatic veins(SHVs).This study introduces a novel technique utilizing the ventral avascular area of the inferior vena cava(IVC),allowing SHVs to be addressed after parenchymal transection,thereby reducing surgical complexity and improving outcomes in in situ LLR.AIM To introduce and evaluate a novel LLR technique using the ventral avascular area of the IVC and compare its short-term outcomes with conventional methods.METHODS The clinical cohort data of patients with pathologically confirmed hepatocellular carcinoma or intrahepatic cholangiocarcinoma who underwent conventional LLR and novel LLR between July 2021 and July 2023 at the First Affiliated Hospital of Chongqing Medical University were retrospectively analyzed.In novel LLR,we initially separated the caudate lobe from the IVC using dissecting forceps along the ventral avascular area of the IVC.Then,we transected the parenchyma of the left and right caudate lobes from the caudal side to the cephalic side using the avascular area as a marker.Subsequently,we addressed the SHVs and finally dissected the root of the right hepatic vein or left hepatic vein.The short-term postoperative outcomes and oncological results of the two approaches were evaluated and compared.RESULTS A total of 256 patients were included,with 150(58.59%)undergoing conventional LLR and 106(41.41%)undergoing novel LLR.The novel technique resulted in significantly larger tumor resections(6.47±2.96 cm vs 4.01±2.33 cm,P<0.001),shorter operative times(199.57±60.37 minutes vs 262.33±83.90 minutes,P<0.001),less intraoperative blood loss(206.92±37.09 mL vs 363.34±131.27 mL,P<0.001),and greater resection volume(345.11±31.40 mL vs 264.38±31.98 mL,P<0.001)compared to conventional LLR.CONCLUSION This novel technique enhances liver resection outcomes by reducing intraoperative complications such as bleeding and tumor compression.It facilitates a safer,in situ removal of complex liver tumors,even in challenging anatomical locations.Compared to conventional methods,this technique offers significant advantages,including reduced operative time,blood loss,and improved overall surgical efficiency.
文摘Background: Life-threatening bleeding is a major cause of trauma-related deaths. Stop the Bleed—Active bleeding control (ABC) program in Hyderabad recently showed that lay first responders can be effectively trained. However, the willingness of high school students to train in bleeding control is unknown. We report Stop the Bleed training needs assessment from high schools in India and estimate the potential multiplier effect. Methods: A cross-sectional survey was conducted from 12 randomly selected schools in Hyderabad. The study was to understand current knowledge, skills and willingness to get trained and respond to life-threatening bleeding from injuries. 107 Participants (35 Teachers and 72 students) were purposively selected for telephonic interviews with a structured questionnaire. Results: Response rate was 93% overall. 80% of participants have never been trained in bleeding control. 84% reported willingness to be trained, train others and help bleeding victims. All the teachers reported that stop the bleed training would be useful in high schools. 70.6% of teachers recommended that training could start from middle school (10 to 15 years), 47% preferred the online training mode. Only 20% of participants had prior training in lifesaving first aid and 32% did not know the number of emergency medical services (EMS). Each trained participant has the potential to train 3 to 4 people at the household level and perhaps more at the community level. Conclusion: The surveyed schools in Hyderabad do not have the knowledge, skills, or training curriculum in Stop the Bleed. Students and teachers are willing to be trained and train others, with great potential for a “multiplier-effect” in the community.
文摘Understanding and managing the bleeding＇s causes is essential for a good surgical practice in general. In fact, it is crucial to know how to manage and control this problem （sometimes simply annoying, but that may be able to cause even dangerous consequences） with a comprehensive and multidisciplinary approach, trying to use all the means is available today. The goal of this paper is to describe, even through a brief review of the literature--the State of Art about the bleeding control in oral surgery, the proper use of surgical devices and the NOACs （new oral anticoagulants） appearance.
基金This work was co-funded by the National Natural Science Foundation of China(Nos.U20A2070,12025202,and 12172175)the National Science and Technology Major Project,China(No.J2019-II-0014-0035).
文摘The hysteresis during the throat regulation process of a supersonic variable inlet is unconducive to restart.Hence,detailed experimental studies of such a hysteresis and its control are necessary.A throat variable supersonic inlet was designed at a shock-on-lip Mach number of 4.0 and an Internal Contraction Ratio(ICR)ranging over 1.21–2.94.Meanwhile,a distributed bleed system was proposed to suppress the hysteresis.The wind tunnel tests were conducted at Mach number 2.9.The throat regulation processes were recorded using a high-speed schlieren and dynamic pressure acquisition system.The results indicate that the unstart and restart ICRs during the uncontrolled inlet’s throat regulation process were 1.95 and 1.48,respectively,demonstrating an unstart-restart hysteresis.Four typical flowfields were summarized during the uncontrolled inlet’s restart process.The proposed bleed control increased the unstart and restart ICRs to 2.06 and 1.75,respectively,and the inlet realized the designed state as the ICR was further decreased to 1.67.The controlled inlet’s hysteresis loop was decreased compared to the uncontrolled inlet.Finally,the mechanism of the hysteresis,dominated by the entrance separation-induced wave system,was clarified.The mechanisms of the bleed control to broaden the unstart and restart boundaries and suppress the hysteresis were elucidated.
文摘In this contribution a quasi-one-dimensional tool for stationary and transient simulations of post-stall flows in multistage axial compressors is presented. An adapted version of the 1D Euler equations with additional source terms is discretized with a finite volume method and solved in time by a fourth-order Runge-Kutta scheme. The equations are discretized at midspan both inside the blade rows and the non-bladed regions. The source terms express the blade-flow interactions and are estimated by calculating the velocity triangles for each blade row. Loss and deviation correlations are implemented and compared to experimental data in normal flow, stalled flow and reversed flow regions. Transient simulations are carried out and a parameter study is presented to analyze the shape of the surge cycles and the frequency of the surge oscillations. At last, a bleeding control strategy is implemented to study the recoverability of the instabilities in a compression system.
