The goal of this effort was to provide a static and dynamic collaborative optimization （CO） model for the design of ship hull structure. The CO model integrated with static, mode and dynamic analyses. In the system-...The goal of this effort was to provide a static and dynamic collaborative optimization （CO） model for the design of ship hull structure. The CO model integrated with static, mode and dynamic analyses. In the system-level optimization model, a new objective function was advised, integrating all the subsystem-levels＇ objective functions, so as to eliminate the effects of dimensions and magnitude order. The proposed CO architecture enabled multi-objectives of the system and subsystem-level to be considered at both levels during optimization. A bi-level optimization strategy was advised, using the multi-island genetic algorithm. The proposed model was demonstrated with a deck optimization problem of container ship stern. The analysis progress and results of example show that the CO strategy is not only feasible and reliable, but also well suited for use in actual optimization problems of ship design.展开更多
According to some observed dama ge phenomena in the smart structure systems, the issues related to the damage and failures of smart structures are addressed in this paper. A few possible damage patterns and the def...According to some observed dama ge phenomena in the smart structure systems, the issues related to the damage and failures of smart structures are addressed in this paper. A few possible damage patterns and the definition of the failure of the smart structures are given. It is pointed out that more attentions should be paid to the functional failures o f smart structures. The effects on the control the static deformation due to par tial debonding of PZT actuators are analyzed by the finite element method. Preli minary numerical results show that partial debonding of PZT actuators may have a p preciate reduction on their actuating ability thus reducing the control ability and accuracy of the smart structures.展开更多
Failure of arteriovenous fistulas(AVF) to mature and thrombosis in matured fistulas have been the major causes of morbidity and mortality in hemodialysis patients. Stenosis, which occurs due to adverse remodeling in A...Failure of arteriovenous fistulas(AVF) to mature and thrombosis in matured fistulas have been the major causes of morbidity and mortality in hemodialysis patients. Stenosis, which occurs due to adverse remodeling in AVFs, is one of the major underlying factors under both scenarios. Early diagnosis of a stenosis in an AVF can provide an opportunity to intervene in a timelymanner for either assisting the maturation process or avoiding the thrombosis. The goal of surveillance strategies was to supplement the clinical evaluation(i.e., physical examination) of the AVF for better and earlier diagnosis of a developing stenosis. Surveillance strategies were mainly based on measurement of functional hemodynamic endpoints, including blood flow(Q a) to the vascular access and venous access pressure(VAP). As the changes in arterial pressure(MAP) affects the level of VAP, the ratio of VAP to MAP(VAPR = VAP/MAP) was used for diagnosis. A Q a < 400-500 m L/min or a VAPR > 0.55 is considered sign of significant stenosis, which requires immediate intervention. However, due to the complex nature of AVFs, the surveillance strategies have failed to consistently detect stenosis under different scenarios. VAPR has been primarily developed to detect outflow stenosis in arteriovenous grafts, and it hasn't been successful in accurate diagnosis of outflow lesions in AVFs. Similarly, AVFs can maintain relatively high blood flow despite the presence of a significant outflow stenosis and thus, Q a has been found to be a better predictor of only inflow lesions. Similar shortcomings have been reported in the detection of functional severity of coronary stenosis using diagnostic endpoints that were based on either flow or pressure. This limitation has been associated with the fact that both pressure and flow change in the presence of a stenosis and thus, hemodynamic diagnostic endpoints that employ only one of these parameters are inherently prone to inaccuracies. Recent attempts have resulted in development of new diagnostic endpoints that can combine the effects of pressure and flow. These new hemodynamic diagnostic endpoints have shown to be better predictors of functional severity of lesions as compared to either flow or pressure based counterparts. In this review article, we discussed the advantages and limitations of current functional and anatomical diagnostic endpoints in AVFs.展开更多
To investigated characteristics, diagnosis, bowel-cleansing preparation, sedation, and colonoscope length and diameter in Japanese pediatric patients receiving total colonoscopy. METHODSThe present study evaluated con...To investigated characteristics, diagnosis, bowel-cleansing preparation, sedation, and colonoscope length and diameter in Japanese pediatric patients receiving total colonoscopy. METHODSThe present study evaluated consecutive patients aged ≤ 15 years who had undergone their first colonoscopy in Kurume University between January 2007 and February 2015. Data were retrospectively analyzed. We identified 110 pediatric patients who had undergone colonoscopy that had reached the cecum, allowing the observation of the total colon. RESULTSHematochezia, abdominal pain, and diarrhea were the most common symptoms. For bowel-cleansing preparation, pediatric patients aged ≤ 12 years were treated with magnesium citrate, and patients aged 13-15 years were treated with polyethylene glycol 4000. For sedation, thiamylal with pentazocine, which has an analgesic effect, was used in patients aged ≤ 6 years, and midazolam with pentazocine was used in patients aged ≥ 7 years. Regarding the choice of endoscope, short and thin endoscopes were selected for younger patients, particularly patients aged ≤ 3 years. Positive diagnoses were made in 78 patients (70.9%). Inflammatory bowel disease (n = 49, 44.5%), including ulcerative colitis (n = 37, 33.6%) and Crohn’s disease (n = 12, 10.9%), was the most common diagnosis. CONCLUSIONColonoscopy offers a high diagnostic capability for pediatric patients with gastrointestinal symptoms. The selection of appropriate management the performance of colonoscopy is important in pediatric patients.展开更多
Little is written on the management of an innocuouslooking skin scab over an autogenous arteriovenous fistula(AVF)used for haemodialysis.The seriousness of the underlying pathology can be under-estimated,and this may ...Little is written on the management of an innocuouslooking skin scab over an autogenous arteriovenous fistula(AVF)used for haemodialysis.The seriousness of the underlying pathology can be under-estimated,and this may lead to early loss of the AVF,and majorlife-threatening haemorrhage.We describe the management of a 78-year-old patient presenting with an innocuous-looking scab over an AVF and review the pertinent literature on this subject.展开更多
AIM To examine whether high-flow nasal oxygen(HFNO) availability influences the use of general anesthesia(GA) in patients undergoing endoscopic retrograde cholangiopancreatography(ERCP) and endoscopic ultrasound(EUS) ...AIM To examine whether high-flow nasal oxygen(HFNO) availability influences the use of general anesthesia(GA) in patients undergoing endoscopic retrograde cholangiopancreatography(ERCP) and endoscopic ultrasound(EUS) and associated outcomes.METHODS In this retrospective study, patients were stratified into 3 eras between October 1, 2013 and June 30, 2014 based on HFNO availability for deep sedation at the time of their endoscopy. During the first and last 3-mo eras(era 1 and 3), no HFNO was available, whereas it was an option during the second 3-mo era(era 2). The primary outcome was the percent utilization of GA vs deep sedation in each period. Secondary outcomes included oxygen saturation nadir during sedation between periods, as well as procedure duration, and anesthesia-only time between periods and for GA vs sedation cases respectively.RESULTS During the study period 238 ERCP or EUS cases were identified for analysis. Statistical testing was employed and a P < 0.050 was significant unless the Bonferroni correction for multiple comparisons was used. General anesthesia use was significantly lower in era 2 compared to era 1 with the same trend between era 2 and 3(P = 0.012 and 0.045 respectively). The oxygen saturation nadir during sedation was significantly higher in era 2 compared to era 3(P < 0.001) but not between eras 1 and 2(P = 0.028) or 1 and 3(P = 0.069). The procedure time within each era was significantly longer under GA compared to deep sedation(P ≤ 0.007) as was the anesthesia-only time(P ≤ 0.001).CONCLUSION High-flow nasal oxygen availability was associated with decreased GA utilization and improved oxygenation for ERCP and EUS during sedation.展开更多
This paper discusses some mechanical concepts that have been largely applied to structural geology and tectonics, and addresses the problems and misunderstandings in use of these mechanical terms. The purpose is to st...This paper discusses some mechanical concepts that have been largely applied to structural geology and tectonics, and addresses the problems and misunderstandings in use of these mechanical terms. The purpose is to stimulate the interests for structural geologists in using the mechanical principles and methods correctly to solve the geodynamic problems.展开更多
基金Knowledge-based Ship-design Hyper-integrated Platform(KSHIP) of Ministry of Education and Ministry of Finance,P. R. China(No.200512)
文摘The goal of this effort was to provide a static and dynamic collaborative optimization （CO） model for the design of ship hull structure. The CO model integrated with static, mode and dynamic analyses. In the system-level optimization model, a new objective function was advised, integrating all the subsystem-levels＇ objective functions, so as to eliminate the effects of dimensions and magnitude order. The proposed CO architecture enabled multi-objectives of the system and subsystem-level to be considered at both levels during optimization. A bi-level optimization strategy was advised, using the multi-island genetic algorithm. The proposed model was demonstrated with a deck optimization problem of container ship stern. The analysis progress and results of example show that the CO strategy is not only feasible and reliable, but also well suited for use in actual optimization problems of ship design.
文摘According to some observed dama ge phenomena in the smart structure systems, the issues related to the damage and failures of smart structures are addressed in this paper. A few possible damage patterns and the definition of the failure of the smart structures are given. It is pointed out that more attentions should be paid to the functional failures o f smart structures. The effects on the control the static deformation due to par tial debonding of PZT actuators are analyzed by the finite element method. Preli minary numerical results show that partial debonding of PZT actuators may have a p preciate reduction on their actuating ability thus reducing the control ability and accuracy of the smart structures.
文摘Failure of arteriovenous fistulas(AVF) to mature and thrombosis in matured fistulas have been the major causes of morbidity and mortality in hemodialysis patients. Stenosis, which occurs due to adverse remodeling in AVFs, is one of the major underlying factors under both scenarios. Early diagnosis of a stenosis in an AVF can provide an opportunity to intervene in a timelymanner for either assisting the maturation process or avoiding the thrombosis. The goal of surveillance strategies was to supplement the clinical evaluation(i.e., physical examination) of the AVF for better and earlier diagnosis of a developing stenosis. Surveillance strategies were mainly based on measurement of functional hemodynamic endpoints, including blood flow(Q a) to the vascular access and venous access pressure(VAP). As the changes in arterial pressure(MAP) affects the level of VAP, the ratio of VAP to MAP(VAPR = VAP/MAP) was used for diagnosis. A Q a < 400-500 m L/min or a VAPR > 0.55 is considered sign of significant stenosis, which requires immediate intervention. However, due to the complex nature of AVFs, the surveillance strategies have failed to consistently detect stenosis under different scenarios. VAPR has been primarily developed to detect outflow stenosis in arteriovenous grafts, and it hasn't been successful in accurate diagnosis of outflow lesions in AVFs. Similarly, AVFs can maintain relatively high blood flow despite the presence of a significant outflow stenosis and thus, Q a has been found to be a better predictor of only inflow lesions. Similar shortcomings have been reported in the detection of functional severity of coronary stenosis using diagnostic endpoints that were based on either flow or pressure. This limitation has been associated with the fact that both pressure and flow change in the presence of a stenosis and thus, hemodynamic diagnostic endpoints that employ only one of these parameters are inherently prone to inaccuracies. Recent attempts have resulted in development of new diagnostic endpoints that can combine the effects of pressure and flow. These new hemodynamic diagnostic endpoints have shown to be better predictors of functional severity of lesions as compared to either flow or pressure based counterparts. In this review article, we discussed the advantages and limitations of current functional and anatomical diagnostic endpoints in AVFs.
文摘To investigated characteristics, diagnosis, bowel-cleansing preparation, sedation, and colonoscope length and diameter in Japanese pediatric patients receiving total colonoscopy. METHODSThe present study evaluated consecutive patients aged ≤ 15 years who had undergone their first colonoscopy in Kurume University between January 2007 and February 2015. Data were retrospectively analyzed. We identified 110 pediatric patients who had undergone colonoscopy that had reached the cecum, allowing the observation of the total colon. RESULTSHematochezia, abdominal pain, and diarrhea were the most common symptoms. For bowel-cleansing preparation, pediatric patients aged ≤ 12 years were treated with magnesium citrate, and patients aged 13-15 years were treated with polyethylene glycol 4000. For sedation, thiamylal with pentazocine, which has an analgesic effect, was used in patients aged ≤ 6 years, and midazolam with pentazocine was used in patients aged ≥ 7 years. Regarding the choice of endoscope, short and thin endoscopes were selected for younger patients, particularly patients aged ≤ 3 years. Positive diagnoses were made in 78 patients (70.9%). Inflammatory bowel disease (n = 49, 44.5%), including ulcerative colitis (n = 37, 33.6%) and Crohn’s disease (n = 12, 10.9%), was the most common diagnosis. CONCLUSIONColonoscopy offers a high diagnostic capability for pediatric patients with gastrointestinal symptoms. The selection of appropriate management the performance of colonoscopy is important in pediatric patients.
文摘Little is written on the management of an innocuouslooking skin scab over an autogenous arteriovenous fistula(AVF)used for haemodialysis.The seriousness of the underlying pathology can be under-estimated,and this may lead to early loss of the AVF,and majorlife-threatening haemorrhage.We describe the management of a 78-year-old patient presenting with an innocuous-looking scab over an AVF and review the pertinent literature on this subject.
基金Supported by The Department of Anesthesiology and Perioperative Medicine,Tufts Medical Center,Boston,United States
文摘AIM To examine whether high-flow nasal oxygen(HFNO) availability influences the use of general anesthesia(GA) in patients undergoing endoscopic retrograde cholangiopancreatography(ERCP) and endoscopic ultrasound(EUS) and associated outcomes.METHODS In this retrospective study, patients were stratified into 3 eras between October 1, 2013 and June 30, 2014 based on HFNO availability for deep sedation at the time of their endoscopy. During the first and last 3-mo eras(era 1 and 3), no HFNO was available, whereas it was an option during the second 3-mo era(era 2). The primary outcome was the percent utilization of GA vs deep sedation in each period. Secondary outcomes included oxygen saturation nadir during sedation between periods, as well as procedure duration, and anesthesia-only time between periods and for GA vs sedation cases respectively.RESULTS During the study period 238 ERCP or EUS cases were identified for analysis. Statistical testing was employed and a P < 0.050 was significant unless the Bonferroni correction for multiple comparisons was used. General anesthesia use was significantly lower in era 2 compared to era 1 with the same trend between era 2 and 3(P = 0.012 and 0.045 respectively). The oxygen saturation nadir during sedation was significantly higher in era 2 compared to era 3(P < 0.001) but not between eras 1 and 2(P = 0.028) or 1 and 3(P = 0.069). The procedure time within each era was significantly longer under GA compared to deep sedation(P ≤ 0.007) as was the anesthesia-only time(P ≤ 0.001).CONCLUSION High-flow nasal oxygen availability was associated with decreased GA utilization and improved oxygenation for ERCP and EUS during sedation.
文摘This paper discusses some mechanical concepts that have been largely applied to structural geology and tectonics, and addresses the problems and misunderstandings in use of these mechanical terms. The purpose is to stimulate the interests for structural geologists in using the mechanical principles and methods correctly to solve the geodynamic problems.
