Correction to “A Sigmoid-Colon-Straightening Soft Actuator With Peristaltic Motion for Colonoscopy Insertion Assistance: Easycolon” [Apr 21 3577-3584]

2021 ◽  
Vol 6 (3) ◽  
pp. 5736-5736
Author(s):  
Hansoul Kim ◽  
Joonhwan Kim ◽  
Jae Min You ◽  
Seung Woo Lee ◽  
Ki-Uk Kyung ◽  
...  
Author(s):  
Hansoul Kim ◽  
Joonhwan Kim ◽  
Jae Min You ◽  
Seung Woo Lee ◽  
Ki-Uk Kyung ◽  
...  

1954 ◽  
Vol 27 (1) ◽  
pp. 67-74 ◽  
Author(s):  
Joseph Shaiken
Keyword(s):  

Swiss Surgery ◽  
2002 ◽  
Vol 8 (1) ◽  
pp. 7-10 ◽  
Author(s):  
Altinli ◽  
Pekmezci ◽  
Balkan ◽  
Somay ◽  
M. Akif Buyukbese ◽  
...  

Castleman's disease is a benign lymphoid neoplasm first reported as hyperplasia of mediastinal lymph nodes. Some authors referred to the lesions as isolated tumors, described as a variant of Hodgkin's disease with a possibility of a malignant potential and others proposed that the lymphoid masses were of a hamartomatous nature. Three histologic variants and two clinical types of the disease have been described. The disease may occur in almost any area in which lymph nodes are normally found. The most common locations are thorax (63%), abdomen (11%) and axilla (4%). We report two separate histologic types of Castleman's disease which were rare in the literature, mimicking sigmoid colon tumor and Hodgkin lymphoma. The diagnostic and therapeutic aspects of this rare entity is discussed.


Author(s):  
Deepak D. ◽  
Nitesh Kumar ◽  
Shreyas P. Shetty ◽  
Saurabh Jain ◽  
Manoj Bhat

The expensive nature of currently used materials in the soft robotic industry demands the consideration of alternative materials for fabrication. This work investigates the performance of RTV-2 grade silicone rubber for fabrication of a soft actuator. Initially, a cylindrical actuator is fabricated using this material and its performance is experimentally assessed for different pressures. Further, parametric variations of the effect of wall thickness and inflation pressure are studied by numerical methods. Results show that, both wall thickness and inflation pressure are influential parameters which affect the elongation behaviour of the actuator. Thin (1.5 mm) sectioned actuators produced 76.97% more elongation compared to thick sectioned, but the stress induced is 89.61 % higher. Whereas, the thick sectioned actuator (6 mm) showed a higher load transmitting capability. With change in wall thickness from 1.5 mm to 6 mm, the elongation is reduced by 76.97 %, 38.35 %, 21.05 % and 11.43 % at pressure 100 kPa, 75 kPa, 50 kPa and 25 kPa respectively. The induced stress is also found reduced by 89.61 %, 86.66 %, 84.46 % and 68.68 % at these pressures. The average load carrying capacity of the actuator is found to be directly proportional to its wall thickness and inflation pressure.


2020 ◽  
Vol 14 (4) ◽  
pp. 7396-7404
Author(s):  
Abdul Malek Abdul Wahab ◽  
Emiliano Rustighi ◽  
Zainudin A.

Various complex shapes of dielectric electro-active polymer (DEAP) actuator have been promoted for several types of applications. In this study, the actuation and mechanical dynamics characteristics of a new core free flat DEAP soft actuator were investigated. This actuator was developed by Danfoss PolyPower. DC voltage of up to 2000 V was supplied for identifying the actuation characteristics of the actuator and compare with the existing formula. The operational frequency of the actuator was determined by dynamic testing. Then, the soft actuator has been modelled as a uniform bar rigidly fixed at one end and attached to mass at another end. Results from the theoretical model were compared with the experimental results. It was found that the deformation of the current actuator was quadratic proportional to the voltage supplied. It was found that experimental results and theory were not in good agreement for low and high voltage with average percentage error are 104% and 20.7%, respectively. The resonance frequency of the actuator was near 14 Hz. Mass of load added, inhomogeneity and initial tension significantly affected the resonance frequency of the soft actuator. The experimental results were consistent with the theoretical model at zero load. However, due to inhomogeneity, the frequency response function’s plot underlines a poor prediction where the theoretical calculation was far from experimental results as values of load increasing with the average percentage error 15.7%. Hence, it shows the proposed analytical procedure not suitable to provide accurate natural frequency for the DEAP soft actuator.


1997 ◽  
Vol 38 (2) ◽  
pp. 313-319 ◽  
Author(s):  
T. Stefansson ◽  
R. Nyman ◽  
S. Nilsson ◽  
A. Ekbom ◽  
L. Påhlman
Keyword(s):  

2020 ◽  
pp. 1-5
Author(s):  
Anton Stift ◽  
Kerstin Wimmer ◽  
Felix Harpain ◽  
Katharina Wöran ◽  
Thomas Mang ◽  
...  

Introduction: Congenital as well as acquired diseases may be responsible for the development of a megacolon. In adult patients, Clostridium difficile associated infection as well as late-onset of Morbus Hirschsprung disease are known to cause a megacolon. In addition, malignant as well as benign colorectal strictures may lead to intestinal dilatation. In case of an idiopathic megacolon, the underlying cause remains unclear. Case Presentation: We describe the case of a 44-year-old male patient suffering from a long history of chronic constipation. He presented himself with an obscurely dilated large intestine with bowel loops up to 17 centimeters in diameter. Radiological as well as endoscopic examination gave evidence of a spastic process in the sigmoid colon. The patient was treated with a subtotal colectomy and the intraoperative findings revealed a stenotic stricture in the sigmoid colon. Since the histological examination did not find a conclusive reason for the functional stenosis, an immunohistochemical staining was advised. This showed a decrease in interstitial cells of Cajal (ICC) in the stenotic part of the sigmoid colon. Discussion: This case report describes a patient with an idiopathic megacolon, where the underlying cause remained unclear until an immunohistochemical staining of the stenotic colon showed a substantial decrease of ICCs. Various pathologies leading to a megacolon are reviewed and discussed.


Sign in / Sign up

Export Citation Format

Share Document