http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Prashant Singh,Yoonjin Seo,Sarah Ballou,Andrew Ludwig,William Hirsch,Vikram Rangan,Johanna Iturrino,Anthony Lembo,Judy W Nee 대한소화기 기능성질환∙운동학회 2019 Journal of Neurogastroenterology and Motility (JNM Vol.25 No.1
Background/Aims Although symptoms related to the pelvic floor, such as pelvic organ prolapse (POP) and lower urinary tract symptoms (LUTS), are common in patients with chronic constipation (CC), its impact is not clear. Our aims were to investigate the following (1) compare pelvic floor symptom related dysfunction in irritable bowel syndrome with constipation (IBS-C) and functional constipation (FC), and (2) symptom correlation with findings on anorectal manometry (ARM) and balloon expulsion test. Methods This was a retrospective analysis of patients with CC undergoing ARM. IBS-C and FC were diagnosed by Rome III criteria. Pelvic Floor Distress Inventory (PFDI-20) was used to measure pelvic floor symptom distress. Constipation Severity Scale was used to assess constipation severity. Results A total of 107 patients underwent ARM (64 FC, 43 IBS-C). The overall PFDI-20 score in IBS-C was higher compared with FC patients (118.0 vs 79.2, P = 0.001). In those with IBS-C, POP, LUTS, and colorectal symptoms subscales were all higher compared with FC patients (P < 0.05 for each). On multivariable regression, IBS-C (P = 0.001) and higher constipation severity (P = 0.001) were both independently associated with higher PFDI scores. ARM parameters and abnormal balloon expulsion test did not correlate with PFDI scores. Conclusions Compared with FC patients, those with IBS-C have significantly higher distress from pelvic floor specific symptoms including POP and LUTS. Higher abdominal pain among IBS-C patients did not entirely explain these findings. A diagnosis of IBS-C and higher constipation severity correlated with PFDI-20 scores, but dyssynergia did not. Background/Aims Although symptoms related to the pelvic floor, such as pelvic organ prolapse (POP) and lower urinary tract symptoms (LUTS), are common in patients with chronic constipation (CC), its impact is not clear. Our aims were to investigate the following (1) compare pelvic floor symptom related dysfunction in irritable bowel syndrome with constipation (IBS-C) and functional constipation (FC), and (2) symptom correlation with findings on anorectal manometry (ARM) and balloon expulsion test. Methods This was a retrospective analysis of patients with CC undergoing ARM. IBS-C and FC were diagnosed by Rome III criteria. Pelvic Floor Distress Inventory (PFDI-20) was used to measure pelvic floor symptom distress. Constipation Severity Scale was used to assess constipation severity. Results A total of 107 patients underwent ARM (64 FC, 43 IBS-C). The overall PFDI-20 score in IBS-C was higher compared with FC patients (118.0 vs 79.2, P = 0.001). In those with IBS-C, POP, LUTS, and colorectal symptoms subscales were all higher compared with FC patients (P < 0.05 for each). On multivariable regression, IBS-C (P = 0.001) and higher constipation severity (P = 0.001) were both independently associated with higher PFDI scores. ARM parameters and abnormal balloon expulsion test did not correlate with PFDI scores. Conclusions Compared with FC patients, those with IBS-C have significantly higher distress from pelvic floor specific symptoms including POP and LUTS. Higher abdominal pain among IBS-C patients did not entirely explain these findings. A diagnosis of IBS-C and higher constipation severity correlated with PFDI-20 scores, but dyssynergia did not.
Prediction of weld zone shape with effect of tool pin profile in friction stir welding process
Prashant Prakash,Ravi Shankar Anand,Sanjay Kumar Jha 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.1
This article investigates the effect of tool pin profile on weld zone shape using computational fluid dynamics techniques in friction stir welding process. The effect of tool pin profile on weld zone shape was investigated by four different pin profile tools: Cylindrical, conical, cylindrical-conical and stepped-conical. In the numerical simulation process, workpiece material and tool are considered as non-Newtonian fluids and solid material, respectively. And simulation is carried out under transient state condition. Temperature distribution and material flow profile developed by the tool pin profile are analyzed for the understanding of viscosity profile of the weld zone region. Critical iso-viscosity surface is developed from the viscosity profile to determine the difference between deformed and undeformed material, which is finally used to determine the weld zone shape. The simulation result shows that maximum temperature and material flow velocity are produced by stepped-conical pin profile tool with respect to all other tools. It is observed from the iso-viscosity surface analysis that a vaseshaped geometry developed around the contact region of the tool and workpiece. The weld zone shape produced by stepped-conical pin profile tool is cylinder dominant vase shape, and weld zone shape of all other tools is basin dominant vase shape. Numerical model was also validated with experimental results of temperature distribution and weld zone shape thickness which showed good agreement.
Synthesis of thin-multiwalled carbon nanotubes by Fe-Mo/MgO catalyst using sol-gel method
Prashant Dubey,Sang-Kyu Choi,Bawl Kim,Cheol-Jin Lee 한국탄소학회 2012 Carbon Letters Vol.13 No.2
The sol-gel technique has been studied to fabricate a homogeneous Fe-Mo/MgO catalyst. Ambient effects (air, Ar, and H2) on thermal decomposition of the citrate precursor have been systematically investigated to fabricate an Fe-Mo/MgO catalyst. Severe agglomeration of metal catalyst was observed under thermal decomposition of citrate precursor in air atmosphere. Ar/H2 atmosphere effectively restricted agglomeration of bimetallic catalyst and formation of highly-dispersed Fe-Mo/MgO catalyst with high specific surface-area due to the formation of Fe-Mo nanoclusters within MgO support. High-quality thin-multiwalled carbon nanotubes (t-MWCNTs) with uniform diameters were achieved on a large scale by catalytic decomposition of methane over Fe-Mo/MgO catalyst prepared under Ar-atmosphere. The produced t-MWCNTs had outer diameters in the range of 4-8 nm (average diameter ~6.6 nm) and wall numbers in the range of 4-7 graphenes. The as-synthesized t-MWCNTs showed product yields over 450% relative to the utilized Fe-Mo/MgO catalyst, and indicated a purity of about 85%.
Endoscopic Guided Biliary Drainage: How Can We Achieve Efficient Biliary Drainage?
Prashant Kedia,Monica Gaidhane,Michel Kahaleh 대한소화기내시경학회 2013 Clinical Endoscopy Vol.46 No.5
Currently, endoscopic retrograde cholangiopancreatography (ERCP) is the preferred procedure for biliary drainage for various pancreatico-biliary disorders. ERCP is successful in 90% of the cases, but is unsuccessful in cases with altered anatomy or with tumors obstructing access to the duodenum. Due to the morbidity and mortality associated with surgical or percutaneous approaches in unsuccessful ERCP cases, biliary endoscopists have been using endoscopic ultrasound-guided biliary drainage (EUS-BD) more frequently within the last decade in different countries. As with any novel advanced endoscopic procedure that incorporates various approaches, advanced endoscopists all over the world have innovated and adopted diverse EUS-BD techniques. Indications for EUS-BD include failed conventional ERCP, altered anatomy, tumor preventing access into the biliary tree and contraindication to percutaneous access (i.e., ascites, etc.). EUS-BD utilizing EUS-guided rendezvous technique is conducted by creating a tract from either the stomach or the duodenum into the bile duct. Although EUS-BD has rapidly been gaining attraction and popularity in the endoscopic world, the indications and methods have yet to be standardized. There are several access routes and techniques that are employed by advanced endoscopists throughout the world for BD. This article reviews the indications and currently practiced EUS-BD techniques, including indications, technical details (intrahepatic or extrahepatic approach), equipment, patient selection, complications, and overall advantages and limitations.