BACKGROUND:Pulmonary aspiration of gastric contents during tracheal intubation is a lifethreatening complication in emergency patients.Rapid sequence intubation is commonly performed to prevent aspiration but is not a...BACKGROUND:Pulmonary aspiration of gastric contents during tracheal intubation is a lifethreatening complication in emergency patients.Rapid sequence intubation is commonly performed to prevent aspiration but is not associated with low risk of intubation related complications.Although it has been considered that aspiration can be prevented in the lateral position,few studies have evaluated the ability to prevent aspiration.Moreover,this position is not always a favorable position for tracheal intubation.If aspiration can be prevented in a clinically relevant semi-lateral position,it may be advantageous.We assessed the ability to prevent aspiration in the lateral position and various degrees of the semi-lateral position using a vomiting-regurgitation manikin model.METHODS:A manikin's head was placed in the neutral,simple extension,or sniffing position.The amount of aspirated saline into the bronchi during simulated vomiting was measured at semilateral position angles of 0°to 90° in 10° increments.The difference in the vertical height between the mouth corner and the inferior border of the vocal cord was measured radiologically at each semilateral position in the three head-neck positions.RESULTS:Pulmonary aspiration was prevented at the ≥70°,≥80°,and 90° semi-lateral positions in the neutral,simple extension,and sniffing positions,respectively.The mouth was lower than the vocal cord in the semi-lateral position in which aspiration was prevented.CONCLUSION:The lateral or excessive semi-lateral position was necessary to protect the lung from aspiration in the head-neck positions commonly used for tracheal intubation.Prevention of aspiration was difficult within clinically relevant semi-lateral positions.展开更多
BACKGROUND Massive esophageal variceal bleeding can be catastrophic,leading to high morbidity and mortality.Patients experiencing massive esophageal variceal bleeding are at high risk of aspiration and hemorrhagic sho...BACKGROUND Massive esophageal variceal bleeding can be catastrophic,leading to high morbidity and mortality.Patients experiencing massive esophageal variceal bleeding are at high risk of aspiration and hemorrhagic shock in acute episodes.Intubation and bleeding control are the two essential steps for resuscitation of these patients.CASE SUMMARY A 47-year-old male patient was admitted to our hospital with upper digestive tract bleeding.He was diagnosed with alcohol-induced liver cirrhosis and consequent esophagogastric varices.As he did not show a good response to somatostatin and Sengstaken-Blakemore tube placement,the patient was scheduled for endoscopic angiotherapy under anesthesia.Preoperative assessment showed an ASA physical status of III and Child-Pugh classification B.However,massive hemorrhage occurred just after induction of anesthesia.Intubation by video-guided laryngoscopy in the lateral decubitus position was attempted twice and was successful.After that,an experienced endoscopic ultrasound(EUS)specialist performed angiotherapy and occluded the culprit vessel.An ultra-thin gastroscope was then inserted into the endotracheal tube to extract the blood observed in the lobar bronchi.The patient suffered hemorrhagic shock with an estimated blood loss of 1500 mL in 20 min and remained in the intensive care unit for two days.The patient was discharged from our hospital eight days later without major complications.CONCLUSION Intubation in the lateral decubitus position and EUS-guided treatment can be lifesaving procedures in patients with massive upper gastrointestinal hemorrhage.展开更多
Objectives: This study aimed to evaluate operative benefits of artificial pnuemothorax in thoracoscopic esophagectomy in the left lateral decubitus position. Methods: We retrospectively analyzed short-term surgical ou...Objectives: This study aimed to evaluate operative benefits of artificial pnuemothorax in thoracoscopic esophagectomy in the left lateral decubitus position. Methods: We retrospectively analyzed short-term surgical outcomes including learning curve of 60 consecutive patients who underwent thoracoscopic esophagectomy with artificial pnuemothorax in the left lateral decubitus position between April 2010 and November 2012 in our department. Results: The median operation time and intraoperative blood loss were 443 min and 220 ml, respectively, and these values were 174 min and 95 ml, respectively, in the thoracic phase of surgery. The median number of harvested lymph node was 37. Only 1 patient required conversion to open esophagectomy. The postoperative 30-day mortality rate was 1.7%. The thoracic operation time significantly decreased after an experience of 10 cases and intraoperative blood loss during thoracic phasesignificantly decreased after an experience of 20 cases (p < 0.05), and operation time remained constant for the following cases. The number of harvested lymph nodes did not exhibit significant changes with an increase in the number of case experienced. Conclusions: Artificial pneumothorax provided the shorting of learning curve at the thoracoscopic esophagectomy in the left lateral decubitus position.展开更多
Study Objective: We compared the effects of intraoperative body position on blood gas and fluid balance in patients undergoing a thoracoscopic esophagectomy as well as during operation and postoperative laboratory dat...Study Objective: We compared the effects of intraoperative body position on blood gas and fluid balance in patients undergoing a thoracoscopic esophagectomy as well as during operation and postoperative laboratory data. Design: Prospective study. Setting: Operating room and intensive care unit. Patients: ASA physical status 1 and 2 patients (n = 26), scheduled for elective thoracoscopic esophagectomy and immediate reconstruction under general anesthesia with one-lung ventilation were enrolled. Interventions: Patients were assigned to either the lateral (n = 16) or prone (n = 10) position groups based on the planned intraoperative body position. A pneumothorax procedure was concomitantly performed only in the prone position group. Measurements: Fluid balance, PaO2/FIO2 ratio (P/F ratio), and maximum PaCO2 during the operation and postoperative laboratory data were analyzed. Main Results: There were no significant differences between the groups for amount of blood loss, blood transfusion, fluid infusion, or urine output. The P/F ratio during one-lung ventilation was significantly higher in the prone than the lateral position group (379 ± 122 vs. 297 ± 67 mmHg, p = 0.017), as was maximum intraoperative PaCO2 (72.2 ± 15.6 vs. 48.3 ± 6.3 mmHg, p Conclusions: A thoracoscopic esophagectomy in the prone position performed concomitantly with a CO2 pneumothorax procedure resulted in a significantly better P/F ratio during one-lung ventilation as compared to the lateral position, indicating that the prone position is more advantageous for oxygenation.展开更多
With the advent of good designs of nails, straight and angled in the arena of treatment for fractures from surgical neck of humerus to approximately 5 cm above the olecranon fossa, nailing is gaining popularity in rec...With the advent of good designs of nails, straight and angled in the arena of treatment for fractures from surgical neck of humerus to approximately 5 cm above the olecranon fossa, nailing is gaining popularity in recent literature. Many different nails are available in market with different proximal and distal locking configurations. Beach chair and supine are the main principle positions for antegrade humerus nailing. Beach chair or supine is the preferred position by many, but there is always difficulty in distal locking by free hand technique as it is difficult to locate the distal locking hole due to rounded smooth anatomy of anterior distal humerus and fear of neurovascular complications in both anteroposterior and latero-medial locking. The aim of this article is to demonstrate the utility of lateral position in ease of nailing all types of humerus fractures. The technique and illustrations below describe the positioning of patient, image intensifier and free hand postero-anterior distal locking without injury to neurovascular structures.展开更多
Previously, we reported the efficacy of a newly developed inverted overtube in shortening the hemostatic time and obtaining a clear endoscopic view in emergency endoscopic hemostasis. This device also helped us to per...Previously, we reported the efficacy of a newly developed inverted overtube in shortening the hemostatic time and obtaining a clear endoscopic view in emergency endoscopic hemostasis. This device also helped us to perform gastric endoscopic submucosal dissection(ESD) more safely by changing the direction of gravity in the right lateral position. To perform a safe ESD, it is important to make an appropriate angle and distance between the electric knife and the gastric mucosa. In this position, the distance to gastric mucosa is reduced, and the angle of the electric knife changes from vertical to somewhat oblique, facilitating safer cutting.展开更多
BACKGROUND A limited number of studies have demonstrated that sleeping in the left lateral decubitus(LLD)decreases nocturnal reflux in patients with gastroesophageal reflux disease(GERD)compared to right lateral decub...BACKGROUND A limited number of studies have demonstrated that sleeping in the left lateral decubitus(LLD)decreases nocturnal reflux in patients with gastroesophageal reflux disease(GERD)compared to right lateral decubitus(RLD)and supine.AIM This systematic review summarizes the association between sleeping in the LLD position and nocturnal reflux in patients with GERD.METHODS Studies published up to July 17,2023,in MEDLINE,EMBASE,and CENTRAL were searched.Eligible studies were randomized and nonrandomized studies assessing the effect of sleeping in LLD compared to RLD and supine in reducing nocturnal reflux in GERD patients.Outcomes include the acid exposure time(AET)(%time in pH<4),acid clearance time(ACT)(in sec/episode),number of reflux episodes,and improvement in N-GSSIQ scores.RESULTS Two nonrandomized studies showed decreased AET and ACT in LLD sleep position in comparison to RLD(mean difference[MD]-2.03[95%CI:-3.62 to-0.45];-81.84[95%CI:-127.48 to-36.20],respectively)and supine position(MD-2.71[95%CI:-4.34 to-1.09];-74.47[95%CI:-116.26 to-32.69],respectively).There was no difference in AET and ACT between RLD sleep position and supine.Furthermore,one randomized controlled trial investigating the use of electronic sleep positional therapy,which increased the duration of LLD sleep and decreased the duration of RLD sleep compared to sham,showed nocturnal symptoms improvement(improved N-GSSIQ score,increased reflux-free nights,and resolution of nocturnal reflux symptoms).CONCLUSION Current evidence suggests that sleeping on the left side could reduce nocturnal reflux and improve GERD-related quality of life,therefore warranting interventions that promote LLD sleep position.展开更多
In this paper, a novel dual-gate and dielectric-inserted lateral trench insulated gate bipolar transistor （DGDI LTIGBT） structure, which features a double extended trench gate and a dielectric inserted in the drift ...In this paper, a novel dual-gate and dielectric-inserted lateral trench insulated gate bipolar transistor （DGDI LTIGBT） structure, which features a double extended trench gate and a dielectric inserted in the drift region, is proposed and discussed. The device can not only decrease the specific on-resistance Ron,sp , but also simultaneously improve the temperature performance. Simulation results show that the proposed LTIGBT achieves an ultra-low on-state voltage drop of 1.31 V at 700 A·cm-2 with a small half-cell pitch of 10.5 μm, a specific on-resistance R on,sp of 187 mΩ·mm2, and a high breakdown voltage of 250 V. The on-state voltage drop of the DGDI LTIGBT is 18% less than that of the DI LTIGBT and 30.3% less than that of the conventional LTIGBT. The proposed LTIGBT exhibits a good positive temperature coefficient for safety paralleling to handling larger currents and enhances the short-circuit capability while maintaining a low self-heating effect. Furthermore, it also shows a better tradeoff between the specific on-resistance and the turnoff loss, although it has a longer turnoff delay time.展开更多
A numerical method is used to model a capsule migration in a microchannel with small Reynolds number Re = 0.01. The capsule is modeled as a liquid drop sur- rounded by a neo-Hookean elastic membrane. The numer- ical m...A numerical method is used to model a capsule migration in a microchannel with small Reynolds number Re = 0.01. The capsule is modeled as a liquid drop sur- rounded by a neo-Hookean elastic membrane. The numer- ical model combines immersed boundary with lattice Boltz- mann method （IB-LBM）. The LBM is used to simulate fixed Cartesian grid while the IBM is utilized to implement the fluid-structure interaction by a set of Lagrangian moving grids for the membrane. The effect of shear elasticity and bending stiffness are both considered. The results show the significance of elastic modulus and initial lateral position on deformation and morphological properties of a circular cap- sule. The wall effect becomes stronger as the capsule ini- tial position gets closer to the channel wall. As the elastic modulus of membrane increases, the capsule undergoes less pronounced deformation and velocity in direction x is de- creased, thus, the capsule motion is slower than the back- ground flow. The best agreement between the present model and experiments for migration velocity takes place for the capsule with normal to moderate membrane elastic modulus. The results are in good agreement with experiment study of Coupier et al. and previous numerical studies. Therefore, the IB-LBM can be employed to make prediction in vitro and in vivo studies of capsule deformation.展开更多
BACKGROUND Meralgia paresthetica(MP)is an entrapment mononeuropathy of the lateral femoral cutaneous nerve(LFCN).Although structural abnormalities in nerve tissues can be confirmed using ultrasonography,this is not ro...BACKGROUND Meralgia paresthetica(MP)is an entrapment mononeuropathy of the lateral femoral cutaneous nerve(LFCN).Although structural abnormalities in nerve tissues can be confirmed using ultrasonography,this is not routinely performed.CASE SUMMARY Herein,we present the case of a 52-year-old woman who developed MP after laparoscopic gynecological surgery.The patient was referred to our clinic from an obstetrics and gynecology clinic with symptoms of numbness and a tingling sensation in the left anterolateral thigh,which developed after surgery performed 5 mo earlier.Tests were performed to assess the disease status and determine the underlying causes.Ultrasonographic examination revealed an anatomical variation,where the left LFCN was entrapped within the inguinal ligament.This case suggests that performing ultrasonographic examination before and after surgery in the lithotomy position could help prevent MP.CONCLUSION This case demonstrates the value of ultrasonography in detecting anatomical variation and diagnosing persistent MP.Ultrasonography should be considered an adjunct to electromyography for optimal MP management.Further,this case would help other clinicians determine patient prognosis and decide on targeted treatment strategies.展开更多
Introduction:Awake fiberoptic bronchoscopy has long been considered the criterion standard for the management of difficult airways because of large thyroid malignancies.After an unsuccessful attempt to intubate with a...Introduction:Awake fiberoptic bronchoscopy has long been considered the criterion standard for the management of difficult airways because of large thyroid malignancies.After an unsuccessful attempt to intubate with a fiberoptic bronchoscope in the supine position,the decision to switch to the left lateral position was made.We present this case to propose the utilization of the lateral position for awake intubation.Case presentation:We report a rare case of a patient with a large papillary carcinoma of the thyroid planned for surgical excision.The patient presented to our hospital with complaints of difficulty breathing while lying down in the supine position and oozing blood from the necrotic tissue.The breathing difficulties subsided in the lateral position.Conclusion:We demonstrated how the left lateral position with an adjunct maneuver facilitates intubation in large thyroid malignancies.展开更多
Taking advantage of the lateral line organ, fish can navigate, feed, and avoid predators and obstacles by sensing surrounding flow fields. The lateral line organ provides an important reference for the development of ...Taking advantage of the lateral line organ, fish can navigate, feed, and avoid predators and obstacles by sensing surrounding flow fields. The lateral line organ provides an important reference for the development of new underwater detection technology. Inspired by the lateral line organ, in this paper, for the sake of localizing the target dipole source in three-dimensional underwater space, an artificial lateral line consisting of nine underwater pressure sensors forming a cross-shaped sensor array is applied. Combined with the method of gener- alized regression neural network, which is suitable for solving nonlinear pattern recognition problems, a corresponding experimental platform has been built to sample data for training the neural network from a 12 cm by 12 cm by 24 cm cuboid space. The experimental results indicate that the cross-shaped artificial lateral line can localize the target dipole source two body-lengths away. The well- performing perceptual distance is below 13 cm away from the sensing array. Moreover, decreasing the data sampling interval and in- creasing the number of sensors utilized can help improve the positioning accuracy.展开更多
Cu(In,Ga)Se2(CIGS) based multilayer heterojunction, as one of the best high efficiency thin film solar cells, has attracted great interest due to its outstanding features. However, the present studies are primarily fo...Cu(In,Ga)Se2(CIGS) based multilayer heterojunction, as one of the best high efficiency thin film solar cells, has attracted great interest due to its outstanding features. However, the present studies are primarily focused on the structure optimization and modulation in order to enhance the photoelectric conversion efficiency. Here, we exploit another application of this multilayer heterostructure in photoresistance-modulated position sensitive detector by introducing lateral photoresistance effect.The lateral photoresistance measurements show that this multilayer heterojunction exhibits a wide spectral response(~330 to ~1150 nm) and excellent bipolar photoresistance performances(position sensitivity of ~63.26 X/mm and nonlinearity <4.5%), and a fast response speed(rise and fall time of ~14.46 and^14.42 ms, respectively). More importantly, based on the lateral photoresistance effect, the CIGS heterostructure may also be developed as a position-dependent resistance memory device, which can be modulated by changing laser intensity, wavelength, and bias voltage with excellent stability and repeatability, and the position resolution reaches up to 1 lm. These results can be well explained by considering the diffusion and the drift model of carriers in the CIGS multilayer heterojunction. This work provides a new approach of achieving novel photoelectric sensors and memory devices based on the traditional photovoltaic heterostructures.展开更多
文摘BACKGROUND:Pulmonary aspiration of gastric contents during tracheal intubation is a lifethreatening complication in emergency patients.Rapid sequence intubation is commonly performed to prevent aspiration but is not associated with low risk of intubation related complications.Although it has been considered that aspiration can be prevented in the lateral position,few studies have evaluated the ability to prevent aspiration.Moreover,this position is not always a favorable position for tracheal intubation.If aspiration can be prevented in a clinically relevant semi-lateral position,it may be advantageous.We assessed the ability to prevent aspiration in the lateral position and various degrees of the semi-lateral position using a vomiting-regurgitation manikin model.METHODS:A manikin's head was placed in the neutral,simple extension,or sniffing position.The amount of aspirated saline into the bronchi during simulated vomiting was measured at semilateral position angles of 0°to 90° in 10° increments.The difference in the vertical height between the mouth corner and the inferior border of the vocal cord was measured radiologically at each semilateral position in the three head-neck positions.RESULTS:Pulmonary aspiration was prevented at the ≥70°,≥80°,and 90° semi-lateral positions in the neutral,simple extension,and sniffing positions,respectively.The mouth was lower than the vocal cord in the semi-lateral position in which aspiration was prevented.CONCLUSION:The lateral or excessive semi-lateral position was necessary to protect the lung from aspiration in the head-neck positions commonly used for tracheal intubation.Prevention of aspiration was difficult within clinically relevant semi-lateral positions.
基金National Natural Science Foundation of China to CBL,No.81971876National Key Research and Development Program of China to FXM,No.2018YFC2001900.
文摘BACKGROUND Massive esophageal variceal bleeding can be catastrophic,leading to high morbidity and mortality.Patients experiencing massive esophageal variceal bleeding are at high risk of aspiration and hemorrhagic shock in acute episodes.Intubation and bleeding control are the two essential steps for resuscitation of these patients.CASE SUMMARY A 47-year-old male patient was admitted to our hospital with upper digestive tract bleeding.He was diagnosed with alcohol-induced liver cirrhosis and consequent esophagogastric varices.As he did not show a good response to somatostatin and Sengstaken-Blakemore tube placement,the patient was scheduled for endoscopic angiotherapy under anesthesia.Preoperative assessment showed an ASA physical status of III and Child-Pugh classification B.However,massive hemorrhage occurred just after induction of anesthesia.Intubation by video-guided laryngoscopy in the lateral decubitus position was attempted twice and was successful.After that,an experienced endoscopic ultrasound(EUS)specialist performed angiotherapy and occluded the culprit vessel.An ultra-thin gastroscope was then inserted into the endotracheal tube to extract the blood observed in the lobar bronchi.The patient suffered hemorrhagic shock with an estimated blood loss of 1500 mL in 20 min and remained in the intensive care unit for two days.The patient was discharged from our hospital eight days later without major complications.CONCLUSION Intubation in the lateral decubitus position and EUS-guided treatment can be lifesaving procedures in patients with massive upper gastrointestinal hemorrhage.
文摘Objectives: This study aimed to evaluate operative benefits of artificial pnuemothorax in thoracoscopic esophagectomy in the left lateral decubitus position. Methods: We retrospectively analyzed short-term surgical outcomes including learning curve of 60 consecutive patients who underwent thoracoscopic esophagectomy with artificial pnuemothorax in the left lateral decubitus position between April 2010 and November 2012 in our department. Results: The median operation time and intraoperative blood loss were 443 min and 220 ml, respectively, and these values were 174 min and 95 ml, respectively, in the thoracic phase of surgery. The median number of harvested lymph node was 37. Only 1 patient required conversion to open esophagectomy. The postoperative 30-day mortality rate was 1.7%. The thoracic operation time significantly decreased after an experience of 10 cases and intraoperative blood loss during thoracic phasesignificantly decreased after an experience of 20 cases (p < 0.05), and operation time remained constant for the following cases. The number of harvested lymph nodes did not exhibit significant changes with an increase in the number of case experienced. Conclusions: Artificial pneumothorax provided the shorting of learning curve at the thoracoscopic esophagectomy in the left lateral decubitus position.
文摘Study Objective: We compared the effects of intraoperative body position on blood gas and fluid balance in patients undergoing a thoracoscopic esophagectomy as well as during operation and postoperative laboratory data. Design: Prospective study. Setting: Operating room and intensive care unit. Patients: ASA physical status 1 and 2 patients (n = 26), scheduled for elective thoracoscopic esophagectomy and immediate reconstruction under general anesthesia with one-lung ventilation were enrolled. Interventions: Patients were assigned to either the lateral (n = 16) or prone (n = 10) position groups based on the planned intraoperative body position. A pneumothorax procedure was concomitantly performed only in the prone position group. Measurements: Fluid balance, PaO2/FIO2 ratio (P/F ratio), and maximum PaCO2 during the operation and postoperative laboratory data were analyzed. Main Results: There were no significant differences between the groups for amount of blood loss, blood transfusion, fluid infusion, or urine output. The P/F ratio during one-lung ventilation was significantly higher in the prone than the lateral position group (379 ± 122 vs. 297 ± 67 mmHg, p = 0.017), as was maximum intraoperative PaCO2 (72.2 ± 15.6 vs. 48.3 ± 6.3 mmHg, p Conclusions: A thoracoscopic esophagectomy in the prone position performed concomitantly with a CO2 pneumothorax procedure resulted in a significantly better P/F ratio during one-lung ventilation as compared to the lateral position, indicating that the prone position is more advantageous for oxygenation.
文摘With the advent of good designs of nails, straight and angled in the arena of treatment for fractures from surgical neck of humerus to approximately 5 cm above the olecranon fossa, nailing is gaining popularity in recent literature. Many different nails are available in market with different proximal and distal locking configurations. Beach chair and supine are the main principle positions for antegrade humerus nailing. Beach chair or supine is the preferred position by many, but there is always difficulty in distal locking by free hand technique as it is difficult to locate the distal locking hole due to rounded smooth anatomy of anterior distal humerus and fear of neurovascular complications in both anteroposterior and latero-medial locking. The aim of this article is to demonstrate the utility of lateral position in ease of nailing all types of humerus fractures. The technique and illustrations below describe the positioning of patient, image intensifier and free hand postero-anterior distal locking without injury to neurovascular structures.
文摘Previously, we reported the efficacy of a newly developed inverted overtube in shortening the hemostatic time and obtaining a clear endoscopic view in emergency endoscopic hemostasis. This device also helped us to perform gastric endoscopic submucosal dissection(ESD) more safely by changing the direction of gravity in the right lateral position. To perform a safe ESD, it is important to make an appropriate angle and distance between the electric knife and the gastric mucosa. In this position, the distance to gastric mucosa is reduced, and the angle of the electric knife changes from vertical to somewhat oblique, facilitating safer cutting.
文摘BACKGROUND A limited number of studies have demonstrated that sleeping in the left lateral decubitus(LLD)decreases nocturnal reflux in patients with gastroesophageal reflux disease(GERD)compared to right lateral decubitus(RLD)and supine.AIM This systematic review summarizes the association between sleeping in the LLD position and nocturnal reflux in patients with GERD.METHODS Studies published up to July 17,2023,in MEDLINE,EMBASE,and CENTRAL were searched.Eligible studies were randomized and nonrandomized studies assessing the effect of sleeping in LLD compared to RLD and supine in reducing nocturnal reflux in GERD patients.Outcomes include the acid exposure time(AET)(%time in pH<4),acid clearance time(ACT)(in sec/episode),number of reflux episodes,and improvement in N-GSSIQ scores.RESULTS Two nonrandomized studies showed decreased AET and ACT in LLD sleep position in comparison to RLD(mean difference[MD]-2.03[95%CI:-3.62 to-0.45];-81.84[95%CI:-127.48 to-36.20],respectively)and supine position(MD-2.71[95%CI:-4.34 to-1.09];-74.47[95%CI:-116.26 to-32.69],respectively).There was no difference in AET and ACT between RLD sleep position and supine.Furthermore,one randomized controlled trial investigating the use of electronic sleep positional therapy,which increased the duration of LLD sleep and decreased the duration of RLD sleep compared to sham,showed nocturnal symptoms improvement(improved N-GSSIQ score,increased reflux-free nights,and resolution of nocturnal reflux symptoms).CONCLUSION Current evidence suggests that sleeping on the left side could reduce nocturnal reflux and improve GERD-related quality of life,therefore warranting interventions that promote LLD sleep position.
基金the Major Program of the National Natural Science Foundation of China(Grant No.2009ZX02305-006)the National Natural Science Foundation of China(Grant No.61076082)
文摘In this paper, a novel dual-gate and dielectric-inserted lateral trench insulated gate bipolar transistor （DGDI LTIGBT） structure, which features a double extended trench gate and a dielectric inserted in the drift region, is proposed and discussed. The device can not only decrease the specific on-resistance Ron,sp , but also simultaneously improve the temperature performance. Simulation results show that the proposed LTIGBT achieves an ultra-low on-state voltage drop of 1.31 V at 700 A·cm-2 with a small half-cell pitch of 10.5 μm, a specific on-resistance R on,sp of 187 mΩ·mm2, and a high breakdown voltage of 250 V. The on-state voltage drop of the DGDI LTIGBT is 18% less than that of the DI LTIGBT and 30.3% less than that of the conventional LTIGBT. The proposed LTIGBT exhibits a good positive temperature coefficient for safety paralleling to handling larger currents and enhances the short-circuit capability while maintaining a low self-heating effect. Furthermore, it also shows a better tradeoff between the specific on-resistance and the turnoff loss, although it has a longer turnoff delay time.
文摘A numerical method is used to model a capsule migration in a microchannel with small Reynolds number Re = 0.01. The capsule is modeled as a liquid drop sur- rounded by a neo-Hookean elastic membrane. The numer- ical model combines immersed boundary with lattice Boltz- mann method （IB-LBM）. The LBM is used to simulate fixed Cartesian grid while the IBM is utilized to implement the fluid-structure interaction by a set of Lagrangian moving grids for the membrane. The effect of shear elasticity and bending stiffness are both considered. The results show the significance of elastic modulus and initial lateral position on deformation and morphological properties of a circular cap- sule. The wall effect becomes stronger as the capsule ini- tial position gets closer to the channel wall. As the elastic modulus of membrane increases, the capsule undergoes less pronounced deformation and velocity in direction x is de- creased, thus, the capsule motion is slower than the back- ground flow. The best agreement between the present model and experiments for migration velocity takes place for the capsule with normal to moderate membrane elastic modulus. The results are in good agreement with experiment study of Coupier et al. and previous numerical studies. Therefore, the IB-LBM can be employed to make prediction in vitro and in vivo studies of capsule deformation.
文摘BACKGROUND Meralgia paresthetica(MP)is an entrapment mononeuropathy of the lateral femoral cutaneous nerve(LFCN).Although structural abnormalities in nerve tissues can be confirmed using ultrasonography,this is not routinely performed.CASE SUMMARY Herein,we present the case of a 52-year-old woman who developed MP after laparoscopic gynecological surgery.The patient was referred to our clinic from an obstetrics and gynecology clinic with symptoms of numbness and a tingling sensation in the left anterolateral thigh,which developed after surgery performed 5 mo earlier.Tests were performed to assess the disease status and determine the underlying causes.Ultrasonographic examination revealed an anatomical variation,where the left LFCN was entrapped within the inguinal ligament.This case suggests that performing ultrasonographic examination before and after surgery in the lithotomy position could help prevent MP.CONCLUSION This case demonstrates the value of ultrasonography in detecting anatomical variation and diagnosing persistent MP.Ultrasonography should be considered an adjunct to electromyography for optimal MP management.Further,this case would help other clinicians determine patient prognosis and decide on targeted treatment strategies.
文摘Introduction:Awake fiberoptic bronchoscopy has long been considered the criterion standard for the management of difficult airways because of large thyroid malignancies.After an unsuccessful attempt to intubate with a fiberoptic bronchoscope in the supine position,the decision to switch to the left lateral position was made.We present this case to propose the utilization of the lateral position for awake intubation.Case presentation:We report a rare case of a patient with a large papillary carcinoma of the thyroid planned for surgical excision.The patient presented to our hospital with complaints of difficulty breathing while lying down in the supine position and oozing blood from the necrotic tissue.The breathing difficulties subsided in the lateral position.Conclusion:We demonstrated how the left lateral position with an adjunct maneuver facilitates intubation in large thyroid malignancies.
基金The author appreciates the support of the National Natural Science Foundation of China （Grant Nos. 51675528 and 51605482 as well as the National Key R＆D Program of China （Grant No. 2016YFF0203400）. The author also thanks Kehong Lv and Peng Yang for guiding in the design of the experimental platform. Besides, the author thanks Qin Wang and Bailiang Chen for assisting in the fabrication of the sensor array and the experimental platform.
文摘Taking advantage of the lateral line organ, fish can navigate, feed, and avoid predators and obstacles by sensing surrounding flow fields. The lateral line organ provides an important reference for the development of new underwater detection technology. Inspired by the lateral line organ, in this paper, for the sake of localizing the target dipole source in three-dimensional underwater space, an artificial lateral line consisting of nine underwater pressure sensors forming a cross-shaped sensor array is applied. Combined with the method of gener- alized regression neural network, which is suitable for solving nonlinear pattern recognition problems, a corresponding experimental platform has been built to sample data for training the neural network from a 12 cm by 12 cm by 24 cm cuboid space. The experimental results indicate that the cross-shaped artificial lateral line can localize the target dipole source two body-lengths away. The well- performing perceptual distance is below 13 cm away from the sensing array. Moreover, decreasing the data sampling interval and in- creasing the number of sensors utilized can help improve the positioning accuracy.
基金supported by the National Natural Science Foundation of China (11704094, 11504076, 51372064, 61405040, 51622205, 61675027, 51432005, and 61505010)the Natural Science Foundation of Hebei Province (F2019201047, F2018201198, F2017201141, and E2017201227)the Natural Science Foundation for Distinguished Young Scholars of Hebei University (2015JQ03)。
文摘Cu(In,Ga)Se2(CIGS) based multilayer heterojunction, as one of the best high efficiency thin film solar cells, has attracted great interest due to its outstanding features. However, the present studies are primarily focused on the structure optimization and modulation in order to enhance the photoelectric conversion efficiency. Here, we exploit another application of this multilayer heterostructure in photoresistance-modulated position sensitive detector by introducing lateral photoresistance effect.The lateral photoresistance measurements show that this multilayer heterojunction exhibits a wide spectral response(~330 to ~1150 nm) and excellent bipolar photoresistance performances(position sensitivity of ~63.26 X/mm and nonlinearity <4.5%), and a fast response speed(rise and fall time of ~14.46 and^14.42 ms, respectively). More importantly, based on the lateral photoresistance effect, the CIGS heterostructure may also be developed as a position-dependent resistance memory device, which can be modulated by changing laser intensity, wavelength, and bias voltage with excellent stability and repeatability, and the position resolution reaches up to 1 lm. These results can be well explained by considering the diffusion and the drift model of carriers in the CIGS multilayer heterojunction. This work provides a new approach of achieving novel photoelectric sensors and memory devices based on the traditional photovoltaic heterostructures.
