AIM: TO introduce a new method: small endoscopic sphincterotomy (ES) combined with endoscopic papillary large balloon dilation (SES + EPLBD) to treat patients with large biliary stones.METHODS: Retrieval of la...AIM: TO introduce a new method: small endoscopic sphincterotomy (ES) combined with endoscopic papillary large balloon dilation (SES + EPLBD) to treat patients with large biliary stones.METHODS: Retrieval of large biliary stones was performed in 88 patients. Mean stone size was 14 ± 3 mm and mean number of stones was 2.5 ± 3.5. Firstly, ES with a small incision was performed. Next, endoscopic papillary dilation was performed with a large balloon to slowly match the size of the bile duct. Stones were then retrieved from the biliary duct with a balloon and a basket.RESULTS: Stone retrieval was successful in all cases except one cystic duct stone case without the need to crush large stones. Mean procedure time was 30 ± 5 min. Dilating the papillary orifice with a large balloon made it possible to remove large stones smoothly without crushing them. After dilation with the large balloon, there were some instances of oozing, but no perforations. One instance of post-procedural pancreatitis (1%) occurred. CONCLUSION: SES + EPLBD was effective for the retrieval of large biliary stones without the use of mechanical lithotripsy.展开更多
Although there are numerous causes of acute panc-reatitis, an etiology cannot always be found. Two potential etiologies, microlithiasis and sphincter of Oddi dysfunction, are discussed in this review. Gallbladder micr...Although there are numerous causes of acute panc-reatitis, an etiology cannot always be found. Two potential etiologies, microlithiasis and sphincter of Oddi dysfunction, are discussed in this review. Gallbladder microlithiasis, missed on transcutaneous ultrasound, is reported as the cause of idiopathic acute pancreatitis in a wide frequency range of 6%-80%. The best diagnostic technique for gallbladder microlithiasis is endoscopic ultrasound although biliary crystal analysis and empiric cholecystectomy remain as reasonable options. In contrast, in patients who are post-cholecystectomy, bile duct microlithiasis does not appear to have a role in the pathogenesis of acute pancreatitis. Sphincter of Oddi dysfunction is present in 30%-65% of patients with idiopathic acute recurrent pancreatitis in whom other diagnoses have been excluded. It is unclear if this sphincter dysfunction was the original etiology of the first episode of pancreatitis although it appears to have a causative role in recurring episodes since sphincter ablation decreases the frequency of recurrent attacks. Unfortunately, this conclusion is primarily based on small retrospective case series; larger prospective studies of the outcome of pancreatic sphincterotomy for SOD-associated acute pancreatitis are sorely needed. Another problem with this diagnosis and its treatment is the concern over potential procedure related complications from endoscopic retrograde cholangiopancreatography (ERCP), manometry and pancreatic sphincterotomy. For these reasons, patients should have recurrent acute pancreatitis, not a single episode, and have a careful informed consent before assessment of the sphincter of Oddi is undertaken.展开更多
For deep tunnel projects,selecting an appropriate initial support distance is critical to improving the self-supporting capacity of surrounding rock.In this work,an intuitive method for determining the tunnel’s initi...For deep tunnel projects,selecting an appropriate initial support distance is critical to improving the self-supporting capacity of surrounding rock.In this work,an intuitive method for determining the tunnel’s initial support distance was proposed.First,based on the convergence-confinement method,a three-dimensional analytical model was constructed by combining an analytical solution of a non-circular tunnel with the Tecplot software.Then,according to the integral failure criteria of rock,the failure tendency coefficients of hard surrounding rock were computed and the spatial distribution plots of that were constructed.On this basis,the tunnel’s key failure positions were identified,and the relationship between the failure tendency coefficient at key failure positions and their distances from the working face was established.Finally,the distance from the working face that corresponds to the critical failure tendency coefficient was taken as the optimal support distance.A practical project was used as an example,and a reasonable initial support distance was successfully determined by applying the developed method.Moreover,it is found that the stability of hard surrounding rock decreases rapidly within the range of 1.0D(D is the tunnel diameter)from the working face,and tends to be stable outside the range of 1.0D.展开更多
Architecture in Jordan characterized by using the most basic raw materials in the natural environment (such as stone, straw and mud etc.). Jordanian designer interacts with natural materials and link these materials...Architecture in Jordan characterized by using the most basic raw materials in the natural environment (such as stone, straw and mud etc.). Jordanian designer interacts with natural materials and link these materials to the local environment and the climatic characteristics of the place. This research focuses on the basic material in construction in Jordan, a substance of natural stone, where the researchers studied the historical relationship between architecture in Jordan and natural stone material, and also studied the properties, specifications, types and methods of formation of this natural material. This research aims to shed light on the modern material of architecture in Jordan and how the architects deal with natural stone and other alternative materials where the architects became underestimate the use of natural stone material and use modern materials far from the architectural heritage and which are sometimes not compatible with the construction environment in Jordan. To conclude from this study the importance of maintaining the continuity of the historical relationship between natural stone and Jordanian architecture, where the study recommends to the possibility of development of use this material through using it in interior architecture to conserve on natural stone as a feedstock in the architecture of Jordan.展开更多
Energy and environment are essential for sustainable development of any nation hence the need for effective and efficient energy production. UNFCCC reports indicate that those who are least responsible for climate cha...Energy and environment are essential for sustainable development of any nation hence the need for effective and efficient energy production. UNFCCC reports indicate that those who are least responsible for climate change are the most vulnerable to its projected impact and the masses are the ones affected by environmental degradation and lack of access to clean and affordable energy services. This paper therefore addresses the effects of these issues, some forms of energy production in Nigeria and the effects on our environment and how it can be effectively managed through innovative policies and partnership with organizations that can help pilot projects that will build a sustainable energy.展开更多
A finite-difference time-domain algorithm was applied to solve Maxwell's equations to obtain the redistribution of an electro- magnetic plane wave in the vicinity of a trailing indent crack (TIC). The roles of five...A finite-difference time-domain algorithm was applied to solve Maxwell's equations to obtain the redistribution of an electro- magnetic plane wave in the vicinity of a trailing indent crack (TIC). The roles of five geometrical parameters playing in light intensification were calculated numerically under the irradiation of a 355-nm normal incidence laser. The results show that the light intensity enhancements between the nearest neighbor pits were remarkable, which may lead to damage, The calculated results reveal that the light intensity enhancement factor (LIEF) can be up to 11.2 when TIC is on the rear-surface. With the increase of the length as well as the depth of pits, LIEF increased. Conversely, with the increase of the axis of pits, LIEF grad- ually declined to a stable status. It was observed that there exists an optima width or gap, which enables LIEF to be increased dramatically and then decreased gently. By comparison, results suggest that the worst cases occur when the depth and the length are both very large, especially if the width equals to 22 and the gap equals the width. This work provides a recom- mended theoretical criterion for defect inspection and classification.展开更多
文摘AIM: TO introduce a new method: small endoscopic sphincterotomy (ES) combined with endoscopic papillary large balloon dilation (SES + EPLBD) to treat patients with large biliary stones.METHODS: Retrieval of large biliary stones was performed in 88 patients. Mean stone size was 14 ± 3 mm and mean number of stones was 2.5 ± 3.5. Firstly, ES with a small incision was performed. Next, endoscopic papillary dilation was performed with a large balloon to slowly match the size of the bile duct. Stones were then retrieved from the biliary duct with a balloon and a basket.RESULTS: Stone retrieval was successful in all cases except one cystic duct stone case without the need to crush large stones. Mean procedure time was 30 ± 5 min. Dilating the papillary orifice with a large balloon made it possible to remove large stones smoothly without crushing them. After dilation with the large balloon, there were some instances of oozing, but no perforations. One instance of post-procedural pancreatitis (1%) occurred. CONCLUSION: SES + EPLBD was effective for the retrieval of large biliary stones without the use of mechanical lithotripsy.
文摘Although there are numerous causes of acute panc-reatitis, an etiology cannot always be found. Two potential etiologies, microlithiasis and sphincter of Oddi dysfunction, are discussed in this review. Gallbladder microlithiasis, missed on transcutaneous ultrasound, is reported as the cause of idiopathic acute pancreatitis in a wide frequency range of 6%-80%. The best diagnostic technique for gallbladder microlithiasis is endoscopic ultrasound although biliary crystal analysis and empiric cholecystectomy remain as reasonable options. In contrast, in patients who are post-cholecystectomy, bile duct microlithiasis does not appear to have a role in the pathogenesis of acute pancreatitis. Sphincter of Oddi dysfunction is present in 30%-65% of patients with idiopathic acute recurrent pancreatitis in whom other diagnoses have been excluded. It is unclear if this sphincter dysfunction was the original etiology of the first episode of pancreatitis although it appears to have a causative role in recurring episodes since sphincter ablation decreases the frequency of recurrent attacks. Unfortunately, this conclusion is primarily based on small retrospective case series; larger prospective studies of the outcome of pancreatic sphincterotomy for SOD-associated acute pancreatitis are sorely needed. Another problem with this diagnosis and its treatment is the concern over potential procedure related complications from endoscopic retrograde cholangiopancreatography (ERCP), manometry and pancreatic sphincterotomy. For these reasons, patients should have recurrent acute pancreatitis, not a single episode, and have a careful informed consent before assessment of the sphincter of Oddi is undertaken.
基金Project(2021JLM-49) supported by Natural Science Basic Research Program of Shaanxi-Joint Fund of Hanjiang to Weihe River Valley Water Diversion Project,ChinaProject(42077248) supported by the National Natural Science Foundation of China
文摘For deep tunnel projects,selecting an appropriate initial support distance is critical to improving the self-supporting capacity of surrounding rock.In this work,an intuitive method for determining the tunnel’s initial support distance was proposed.First,based on the convergence-confinement method,a three-dimensional analytical model was constructed by combining an analytical solution of a non-circular tunnel with the Tecplot software.Then,according to the integral failure criteria of rock,the failure tendency coefficients of hard surrounding rock were computed and the spatial distribution plots of that were constructed.On this basis,the tunnel’s key failure positions were identified,and the relationship between the failure tendency coefficient at key failure positions and their distances from the working face was established.Finally,the distance from the working face that corresponds to the critical failure tendency coefficient was taken as the optimal support distance.A practical project was used as an example,and a reasonable initial support distance was successfully determined by applying the developed method.Moreover,it is found that the stability of hard surrounding rock decreases rapidly within the range of 1.0D(D is the tunnel diameter)from the working face,and tends to be stable outside the range of 1.0D.
文摘Architecture in Jordan characterized by using the most basic raw materials in the natural environment (such as stone, straw and mud etc.). Jordanian designer interacts with natural materials and link these materials to the local environment and the climatic characteristics of the place. This research focuses on the basic material in construction in Jordan, a substance of natural stone, where the researchers studied the historical relationship between architecture in Jordan and natural stone material, and also studied the properties, specifications, types and methods of formation of this natural material. This research aims to shed light on the modern material of architecture in Jordan and how the architects deal with natural stone and other alternative materials where the architects became underestimate the use of natural stone material and use modern materials far from the architectural heritage and which are sometimes not compatible with the construction environment in Jordan. To conclude from this study the importance of maintaining the continuity of the historical relationship between natural stone and Jordanian architecture, where the study recommends to the possibility of development of use this material through using it in interior architecture to conserve on natural stone as a feedstock in the architecture of Jordan.
文摘Energy and environment are essential for sustainable development of any nation hence the need for effective and efficient energy production. UNFCCC reports indicate that those who are least responsible for climate change are the most vulnerable to its projected impact and the masses are the ones affected by environmental degradation and lack of access to clean and affordable energy services. This paper therefore addresses the effects of these issues, some forms of energy production in Nigeria and the effects on our environment and how it can be effectively managed through innovative policies and partnership with organizations that can help pilot projects that will build a sustainable energy.
基金supported by the Scientific Research Foundation for the Central Universities of China(Grant No.2014NZYQN14)
文摘A finite-difference time-domain algorithm was applied to solve Maxwell's equations to obtain the redistribution of an electro- magnetic plane wave in the vicinity of a trailing indent crack (TIC). The roles of five geometrical parameters playing in light intensification were calculated numerically under the irradiation of a 355-nm normal incidence laser. The results show that the light intensity enhancements between the nearest neighbor pits were remarkable, which may lead to damage, The calculated results reveal that the light intensity enhancement factor (LIEF) can be up to 11.2 when TIC is on the rear-surface. With the increase of the length as well as the depth of pits, LIEF increased. Conversely, with the increase of the axis of pits, LIEF grad- ually declined to a stable status. It was observed that there exists an optima width or gap, which enables LIEF to be increased dramatically and then decreased gently. By comparison, results suggest that the worst cases occur when the depth and the length are both very large, especially if the width equals to 22 and the gap equals the width. This work provides a recom- mended theoretical criterion for defect inspection and classification.