Minimally invasive interventional surgery techniques using guidewire-based catheters are widely adopted to treat vascular diseases.However,commonly used interventional catheters lack active guidance.The use of guidewi...Minimally invasive interventional surgery techniques using guidewire-based catheters are widely adopted to treat vascular diseases.However,commonly used interventional catheters lack active guidance.The use of guidewires is associated with risks,including increased exposure to X-rays and potential vascular damage during withdrawal from complex vessels.Herein,we developed sub-millimeter microtubular ionic actuators(0.6-0.8 mm outer diameter)integrated into steerable interventional catheters.These actuators can generate large deformations(>10 mm)under 7 V direct current due to enhanced ion migration,enabling precise navigation without the need for guidewires.The designed catheters achieved active bending and accurate positioning in complex arterial vascular branches within a human model.They were also able to navigate within different arterial locations(e.g.,the innominate,subclavian,and carotid arteries)in pigs without the use of guidewires,and even access the ventricle and deliver contrast medium,indicating their great potential for future endovascular therapy.展开更多
Drug regulation is the most important policy to ensure drug safety.In this article,we analyzed institutional changes and problems in China＇s drug regulation.In addition,suggestions were provided to enhance the capaci...Drug regulation is the most important policy to ensure drug safety.In this article,we analyzed institutional changes and problems in China＇s drug regulation.In addition,suggestions were provided to enhance the capacity of drug regulation,including a clearer functional positioning for drug regulation,increased resource inputs in drug regulation at central level,a more rational allocation of vertical drug regulatory functions,and an improved supervision mechanism for regulatory departments.展开更多
We summarize from previous works the functions of circular vs. longitudinal muscle in esophageal peristaltic bolus transport using a mix of experimental data, the conservation laws of mechanics and mathematical modeli...We summarize from previous works the functions of circular vs. longitudinal muscle in esophageal peristaltic bolus transport using a mix of experimental data, the conservation laws of mechanics and mathematical modeling. Whereas circular muscle tone generates radial closure pressure to create a local peristaltic closure wave, longitudinal muscle tone has two functions, one physiological with mechanical implications, and one purely mechanical. Each of these functions independently reduces the tension of individual circular muscle fibers to maintain closure as a consequence of shortening of longitudinal muscle locally coordinated with increasing circular muscle tone. The physiological function is deduced by combining basic laws of mechanics with concurrent measurements of intraluminal pressure from manometry, and changes in cross sectional muscle area from endoluminal ultrasound from which local longitudinal shortening (LLS) can be accurately obtained. The purely mechanical function of LLS was discovered from mathematical modeling of peristaltic esophageal transport with the axial wall motion generated by LLS. Physiologically, LLS concentrates circular muscle fibers where closure pressure is highest. However, the mechanical function of LLS is to reduce the level of pressure required to maintain closure. The combined physiological and mechanical consequences of LLS are to reduce circular muscle fiber tension and power by as much as 1/10 what would be requiredfor peristalsis without the longitudinal muscle layer, a tremendous benefit that may explain the existence of longitudinal muscle fiber in the gut. We also review what is understood of the role of longitudinal muscle in esophageal emptying, reflux and pathology.展开更多
AIM To elucidate longitudinal changes of an endoscopic Barrett esophagus(BE), especially of short segment endoscopic BE(SSBE). METHODS This study comprised 779 patients who underwent two or more endoscopies between Ja...AIM To elucidate longitudinal changes of an endoscopic Barrett esophagus(BE), especially of short segment endoscopic BE(SSBE). METHODS This study comprised 779 patients who underwent two or more endoscopies between January 2009 and December 2015. The intervals between the first and the last endoscopy were at least 6 mo. The diagnosis of endoscopic BE was based on the criteria proposed by the Japan Esophageal Society and was classified as long segment(LSBE) and SSBE, the latter being further divided into partial and circumferential types. The potential background factors that were deemed to affect BE change included age, gender, antacid therapy use, gastroesophageal reflux disease-suggested symptoms, esophagitis, and hiatus hernia. Time trends of a new appearance and complete regression were investigated by Kaplan-Meier curves. The factors that may affect appearance and complete regression were investigated by χ~2 and Student-t tests, and multivariable Cox regression analysis. RESULTS Incidences of SSBE and LSBE were respectively 21.7% and 0%, with a mean age of 68 years. Complete regression of SSBE was observed in 61.5% of initial SSBE patients, while 12.1% of initially disease free patients experienced an appearance of SSBE. Complete regressions and appearances of BE occurred constantly over time, accounting for 80% and 17% of 5-year cumulative rates. No LSBE development from SSBE was observed. A hiatus hernia was the only significant factor that facilitated BE development(P = 0.03) or hampered(P = 0.007) BE regression. CONCLUSION Both appearances and complete regressions of SSBE occurred over time. A hiatus hernia was the only significant factor affecting the BE story.展开更多
This paper examines systematic differences in earnings management through real activity manipulation and accrual manipulation across 7 Asia countries. The study proposes arguments that in economies with high investor ...This paper examines systematic differences in earnings management through real activity manipulation and accrual manipulation across 7 Asia countries. The study proposes arguments that in economies with high investor protection, managers prefer to manage earnings through real activity manipulation rather than through accrual manipulation because accrual manipulation is more likely to draw auditors or regulators scrutiny than real decisions about pricing and production. The study findings are consistent with prediction. Despite being in economies with high investor protection, managers still have bigger discretion in managing earnings through real activities rather than accrual manipulation.展开更多
This research explored the organization＇s public relationship management practices in corporate blogs on the web. Content analyses of corporate blogs of large Korean firms over two years in a longitudinal design reve...This research explored the organization＇s public relationship management practices in corporate blogs on the web. Content analyses of corporate blogs of large Korean firms over two years in a longitudinal design revealed that relationship management strategies of openness, positivity and sharing of tasks were featured relatively strongly, whereas networking, access, and assurances were enacted relatively weakly. Further, most Korean corporate blogs utilized a tightly controlled top-down strategy. In addition, the use level of relationship management strategy was tied to the kind of corporate blogging strategies, but not to the industry type of the firms. Although utilized the same social media device, corporate blogs enacted different purposes and relational management activities in different countries, indicating that corporate blogs are largely cultural and driven locally.展开更多
Diagnostic imaging is carried out in patients with esophageal carcinoma in order to decide on the therapeutical procedure, to control therapy, to document complications and to assess concomitant diseases. Chest X-rays...Diagnostic imaging is carried out in patients with esophageal carcinoma in order to decide on the therapeutical procedure, to control therapy, to document complications and to assess concomitant diseases. Chest X-rays and esophagograms give a 2-dimensional view of the X-ray absorption in 3-dimensional examination volumes, the diagnostic accuracy thus being limited by overshadowing. Because of the robust examination technique, the broad availability and the low costs chest X-rays are usually used for short-term controls under therapy and follow-up. Esophagography is carried out in order to asses the exact location and length of a known esophageal carcinoma prior to therapy and in order to assess peristaltic disturbances and ?stulas. CT and MRI provide tomographic images with a spatial resolution of up to 1 mm3 allowing the reconstruction of high-resolution images not only in the transversal but also in any other plain. The diagnostic accuracy of esophagography is comparatively high in T1–T3 stages (80%–90%). T1 and T2 tumors cannot be diagnosed by CT and MRI, because both methods do not visualize the mucosa (unlike esophagography and endoscopy) and the esophageal wall layers (unlike EUS). In?ltration depth tends to be overestimated in T1 and T2 carcinomas and to be underestimated in T3 and T4 cancers. CT and MRI cannot detect metastases in normally sized lymph nodes and cannot accurately di?erentiate between benign and malignant lymphadenopathy in enlarged nodes with a reported sensitivities and speci?ties of 60% and 74%, respectively. However, further prospective studies using up to date CT and MR technology are needed to assess the present diagnostic situation. CT and MRI do not only visualize the mediastinum, but also the lungs, the pleura and the skeleton as well as the neck and the abdomen thus providing a comprehensive overview of the TNM stage in 3 body regions.展开更多
MEDIASTINAL cavernous hemangioma is a kind of primary mediastinal mesenchymal tumor that occurs rarely in any age. It was first reported by Shennon in 1914. In this study we reported a case of mediastinal cavernous he...MEDIASTINAL cavernous hemangioma is a kind of primary mediastinal mesenchymal tumor that occurs rarely in any age. It was first reported by Shennon in 1914. In this study we reported a case of mediastinal cavernous hemangioma with abnormal vessel originating from left brachiocephalic vein.展开更多
We recently encountered an unusual case of hilar cholangiocarcinoma in which a solitary recurrence in a mediastinal lymph node occurred two years after curative resection of the primary tumor. A 64-year old woman was ...We recently encountered an unusual case of hilar cholangiocarcinoma in which a solitary recurrence in a mediastinal lymph node occurred two years after curative resection of the primary tumor. A 64-year old woman was admitted to our hospital with a complaint of right hypochondrial discomfort. After imaging studies demonstrated a hilar cholangiocarcinoma in the left hepatic duct, a curative resection of the tumor was performed, consisting of a left hepatic lobectomy along with caudate lobectomy, regional lymph node dissection, and resection of the extrahepatic bile duct. No nodal metastasis was observed histologically. Two years after surgery, the patient was found to have a nodule in the posterior mediastinum, which was thoracoscopically resected. No other swollen lymph nodes, local recurrence, or distant metastasis were noted. Histologically, the nodule proved to be a metastatic lymph node, and adjuvant chemoradiation therapy was initiated. The patient remained well for the four years following her first operation and had no evidence of disease recurrence 28 mo after her second operation. To our knowledge, this case is the first report of solitary recurrence in a mediastinal lymph node after curative resection of hilar cholangiocarcinoma.展开更多
In recent years, there have been a lot of domestic and foreign earnings manipulations. Therefore, it is of great significance to study earnings management and its influencing factors in order to restrict earnings mana...In recent years, there have been a lot of domestic and foreign earnings manipulations. Therefore, it is of great significance to study earnings management and its influencing factors in order to restrict earnings management and ensure the quality of accounting information. This paper studies the impact of internal control related earnings management, and incorporates equity incentives into the impact analysis framework of internal control related earnings management, and studies the effect of equity incentives on the relationship between internal control and accrued earnings management.展开更多
Based on experimental study result of two simply supported beams,which were prestressed by vertical tendons,the research on the weakening effect of vertical prestress ducts on web sections of prestressed concrete box ...Based on experimental study result of two simply supported beams,which were prestressed by vertical tendons,the research on the weakening effect of vertical prestress ducts on web sections of prestressed concrete box girder was carried out. The test result shows that in the condition without grouting into the ducts,the cracking load is evidently lower than that with full grouting,and stirrup stress and principal tension stress at the surface of concrete will increase obviously. Meanwhile,the finite element analysis has been done to the test beams. The research is consistent with the analysis of finite element. The research tells that strengthening the detection and management for the vertical prestress grouting quality have an important meaning to prevent cracking of the prestressed concrete box girder bridge and provide one theoretical and testing basis for analyzing the cracking reason of such bridges.展开更多
In the present work,the heat transfer study focuses on assessment of the impact of bed temperature on the local heat transfer characteristic between a fluidized bed and vertical rifled tubes(38mm-O.D.) in a commercial...In the present work,the heat transfer study focuses on assessment of the impact of bed temperature on the local heat transfer characteristic between a fluidized bed and vertical rifled tubes(38mm-O.D.) in a commercial circulating fluidized bed(CFB) boiler.Heat transfer behavior in a 1296t/h supercritical CFB furnace has been analyzed for Geldart B particle with Sauter mean diameter of 0.219 and 0.246 mm.The heat transfer experiments were conducted for the active heat transfer surface in the form of membrane tube with a longitudinal fin at the tube crest under the normal operating conditions of CFB boiler.A heat transfer analysis of CFB boiler with detailed consideration of the bed-to-wall heat transfer coefficient and the contribution of heat transfer mechanisms inside furnace chamber were investigated using mechanistic heat transfer model based on cluster renewal approach.The predicted values of heat transfer coefficient are compared with empirical correlation for CFB units in large-scale.展开更多
基金the National Natural Science Foundation of China(No.52375293)the Research Fund of State Key Laboratory of Mechanics and Control for Aerospace Structures(Nanjing University of Aeronautics and astronautics,Nos.1005-IZD2300225 and IZD2400217)+2 种基金the Nanjing Life and Health Technology Special Project(No.202305031)the Clinical Competence Enhancement Project in Healthcare(No.JSPH-MB-2022-4)the Medical Engineering Translational Fund of Jiangsu Province Hospital(No.NM202402).
文摘Minimally invasive interventional surgery techniques using guidewire-based catheters are widely adopted to treat vascular diseases.However,commonly used interventional catheters lack active guidance.The use of guidewires is associated with risks,including increased exposure to X-rays and potential vascular damage during withdrawal from complex vessels.Herein,we developed sub-millimeter microtubular ionic actuators(0.6-0.8 mm outer diameter)integrated into steerable interventional catheters.These actuators can generate large deformations(>10 mm)under 7 V direct current due to enhanced ion migration,enabling precise navigation without the need for guidewires.The designed catheters achieved active bending and accurate positioning in complex arterial vascular branches within a human model.They were also able to navigate within different arterial locations(e.g.,the innominate,subclavian,and carotid arteries)in pigs without the use of guidewires,and even access the ventricle and deliver contrast medium,indicating their great potential for future endovascular therapy.
文摘Drug regulation is the most important policy to ensure drug safety.In this article,we analyzed institutional changes and problems in China＇s drug regulation.In addition,suggestions were provided to enhance the capacity of drug regulation,including a clearer functional positioning for drug regulation,increased resource inputs in drug regulation at central level,a more rational allocation of vertical drug regulatory functions,and an improved supervision mechanism for regulatory departments.
文摘We summarize from previous works the functions of circular vs. longitudinal muscle in esophageal peristaltic bolus transport using a mix of experimental data, the conservation laws of mechanics and mathematical modeling. Whereas circular muscle tone generates radial closure pressure to create a local peristaltic closure wave, longitudinal muscle tone has two functions, one physiological with mechanical implications, and one purely mechanical. Each of these functions independently reduces the tension of individual circular muscle fibers to maintain closure as a consequence of shortening of longitudinal muscle locally coordinated with increasing circular muscle tone. The physiological function is deduced by combining basic laws of mechanics with concurrent measurements of intraluminal pressure from manometry, and changes in cross sectional muscle area from endoluminal ultrasound from which local longitudinal shortening (LLS) can be accurately obtained. The purely mechanical function of LLS was discovered from mathematical modeling of peristaltic esophageal transport with the axial wall motion generated by LLS. Physiologically, LLS concentrates circular muscle fibers where closure pressure is highest. However, the mechanical function of LLS is to reduce the level of pressure required to maintain closure. The combined physiological and mechanical consequences of LLS are to reduce circular muscle fiber tension and power by as much as 1/10 what would be requiredfor peristalsis without the longitudinal muscle layer, a tremendous benefit that may explain the existence of longitudinal muscle fiber in the gut. We also review what is understood of the role of longitudinal muscle in esophageal emptying, reflux and pathology.
文摘AIM To elucidate longitudinal changes of an endoscopic Barrett esophagus(BE), especially of short segment endoscopic BE(SSBE). METHODS This study comprised 779 patients who underwent two or more endoscopies between January 2009 and December 2015. The intervals between the first and the last endoscopy were at least 6 mo. The diagnosis of endoscopic BE was based on the criteria proposed by the Japan Esophageal Society and was classified as long segment(LSBE) and SSBE, the latter being further divided into partial and circumferential types. The potential background factors that were deemed to affect BE change included age, gender, antacid therapy use, gastroesophageal reflux disease-suggested symptoms, esophagitis, and hiatus hernia. Time trends of a new appearance and complete regression were investigated by Kaplan-Meier curves. The factors that may affect appearance and complete regression were investigated by χ~2 and Student-t tests, and multivariable Cox regression analysis. RESULTS Incidences of SSBE and LSBE were respectively 21.7% and 0%, with a mean age of 68 years. Complete regression of SSBE was observed in 61.5% of initial SSBE patients, while 12.1% of initially disease free patients experienced an appearance of SSBE. Complete regressions and appearances of BE occurred constantly over time, accounting for 80% and 17% of 5-year cumulative rates. No LSBE development from SSBE was observed. A hiatus hernia was the only significant factor that facilitated BE development(P = 0.03) or hampered(P = 0.007) BE regression. CONCLUSION Both appearances and complete regressions of SSBE occurred over time. A hiatus hernia was the only significant factor affecting the BE story.
文摘This paper examines systematic differences in earnings management through real activity manipulation and accrual manipulation across 7 Asia countries. The study proposes arguments that in economies with high investor protection, managers prefer to manage earnings through real activity manipulation rather than through accrual manipulation because accrual manipulation is more likely to draw auditors or regulators scrutiny than real decisions about pricing and production. The study findings are consistent with prediction. Despite being in economies with high investor protection, managers still have bigger discretion in managing earnings through real activities rather than accrual manipulation.
文摘This research explored the organization＇s public relationship management practices in corporate blogs on the web. Content analyses of corporate blogs of large Korean firms over two years in a longitudinal design revealed that relationship management strategies of openness, positivity and sharing of tasks were featured relatively strongly, whereas networking, access, and assurances were enacted relatively weakly. Further, most Korean corporate blogs utilized a tightly controlled top-down strategy. In addition, the use level of relationship management strategy was tied to the kind of corporate blogging strategies, but not to the industry type of the firms. Although utilized the same social media device, corporate blogs enacted different purposes and relational management activities in different countries, indicating that corporate blogs are largely cultural and driven locally.
文摘Diagnostic imaging is carried out in patients with esophageal carcinoma in order to decide on the therapeutical procedure, to control therapy, to document complications and to assess concomitant diseases. Chest X-rays and esophagograms give a 2-dimensional view of the X-ray absorption in 3-dimensional examination volumes, the diagnostic accuracy thus being limited by overshadowing. Because of the robust examination technique, the broad availability and the low costs chest X-rays are usually used for short-term controls under therapy and follow-up. Esophagography is carried out in order to asses the exact location and length of a known esophageal carcinoma prior to therapy and in order to assess peristaltic disturbances and ?stulas. CT and MRI provide tomographic images with a spatial resolution of up to 1 mm3 allowing the reconstruction of high-resolution images not only in the transversal but also in any other plain. The diagnostic accuracy of esophagography is comparatively high in T1–T3 stages (80%–90%). T1 and T2 tumors cannot be diagnosed by CT and MRI, because both methods do not visualize the mucosa (unlike esophagography and endoscopy) and the esophageal wall layers (unlike EUS). In?ltration depth tends to be overestimated in T1 and T2 carcinomas and to be underestimated in T3 and T4 cancers. CT and MRI cannot detect metastases in normally sized lymph nodes and cannot accurately di?erentiate between benign and malignant lymphadenopathy in enlarged nodes with a reported sensitivities and speci?ties of 60% and 74%, respectively. However, further prospective studies using up to date CT and MR technology are needed to assess the present diagnostic situation. CT and MRI do not only visualize the mediastinum, but also the lungs, the pleura and the skeleton as well as the neck and the abdomen thus providing a comprehensive overview of the TNM stage in 3 body regions.
文摘MEDIASTINAL cavernous hemangioma is a kind of primary mediastinal mesenchymal tumor that occurs rarely in any age. It was first reported by Shennon in 1914. In this study we reported a case of mediastinal cavernous hemangioma with abnormal vessel originating from left brachiocephalic vein.
文摘We recently encountered an unusual case of hilar cholangiocarcinoma in which a solitary recurrence in a mediastinal lymph node occurred two years after curative resection of the primary tumor. A 64-year old woman was admitted to our hospital with a complaint of right hypochondrial discomfort. After imaging studies demonstrated a hilar cholangiocarcinoma in the left hepatic duct, a curative resection of the tumor was performed, consisting of a left hepatic lobectomy along with caudate lobectomy, regional lymph node dissection, and resection of the extrahepatic bile duct. No nodal metastasis was observed histologically. Two years after surgery, the patient was found to have a nodule in the posterior mediastinum, which was thoracoscopically resected. No other swollen lymph nodes, local recurrence, or distant metastasis were noted. Histologically, the nodule proved to be a metastatic lymph node, and adjuvant chemoradiation therapy was initiated. The patient remained well for the four years following her first operation and had no evidence of disease recurrence 28 mo after her second operation. To our knowledge, this case is the first report of solitary recurrence in a mediastinal lymph node after curative resection of hilar cholangiocarcinoma.
文摘In recent years, there have been a lot of domestic and foreign earnings manipulations. Therefore, it is of great significance to study earnings management and its influencing factors in order to restrict earnings management and ensure the quality of accounting information. This paper studies the impact of internal control related earnings management, and incorporates equity incentives into the impact analysis framework of internal control related earnings management, and studies the effect of equity incentives on the relationship between internal control and accrued earnings management.
文摘Based on experimental study result of two simply supported beams,which were prestressed by vertical tendons,the research on the weakening effect of vertical prestress ducts on web sections of prestressed concrete box girder was carried out. The test result shows that in the condition without grouting into the ducts,the cracking load is evidently lower than that with full grouting,and stirrup stress and principal tension stress at the surface of concrete will increase obviously. Meanwhile,the finite element analysis has been done to the test beams. The research is consistent with the analysis of finite element. The research tells that strengthening the detection and management for the vertical prestress grouting quality have an important meaning to prevent cracking of the prestressed concrete box girder bridge and provide one theoretical and testing basis for analyzing the cracking reason of such bridges.
基金financially supported by scientific research No BS-PB-406/301//11
文摘In the present work,the heat transfer study focuses on assessment of the impact of bed temperature on the local heat transfer characteristic between a fluidized bed and vertical rifled tubes(38mm-O.D.) in a commercial circulating fluidized bed(CFB) boiler.Heat transfer behavior in a 1296t/h supercritical CFB furnace has been analyzed for Geldart B particle with Sauter mean diameter of 0.219 and 0.246 mm.The heat transfer experiments were conducted for the active heat transfer surface in the form of membrane tube with a longitudinal fin at the tube crest under the normal operating conditions of CFB boiler.A heat transfer analysis of CFB boiler with detailed consideration of the bed-to-wall heat transfer coefficient and the contribution of heat transfer mechanisms inside furnace chamber were investigated using mechanistic heat transfer model based on cluster renewal approach.The predicted values of heat transfer coefficient are compared with empirical correlation for CFB units in large-scale.
