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Purpose: Fibre optic colonoscopy is usually performed with manual introduction and advancement of the endoscope, but there is potential for a robot capable of locomoting autonomously from the rectum to the caecum. A prototype robot was designed and tested. Methods: The robot colonic endoscope consists in a front body with clockwise helical fin and a rear body with anticlockwise one, both connected via a DC motor. Input voltage is adjusted automatically by the robot, through the use of reinforcement learning, determining speed and direction (forward or backward). Results: Experiments were performed both in-vitro and in-vivo, showing the feasibility of the robot. The device is capable of moving in a slippery environment, and reinforcement learning algorithms such as Q-learning and SARSA can obtain better results than simply applying full tension to the robot. Conclusions: This self-propelled robotic endoscope has potential as an alternative to current fibre optic colonoscopy examination methods, especially with the addition of new sensors under development. [ABSTRACT FROM AUTHOR]

This retrospective study evaluated the influence of vacuum-assisted venous drainage in single-access minimally invasive cardiac surgery. A total of 104 patients who underwent cardiac surgery via minimal access incision were included in this study. Cardiopulmonary bypass was initiated with gravity alone, and vacuum-assisted venous drainage was applied only when the bypass flow was 2.2 l/min/m2 or less. We compared intraoperative variables of the patients to whom vacuum-assisted venous drainage (vacuum group) was applied with those who underwent gravity venous drainage alone (gravity group). In the 13 patients who most recently underwent isolated valve operations without maze procedures, free hemoglobin was measured to evaluate hemolysis. Vacuum-assisted venous drainage was required in 77 (72.6%) patients. Except for a smaller body surface area in the gravity group ( P = 0.0118), patient characteristics did not differ significantly between the two groups. Free hemoglobin 60 mins after the beginning of cardiopulmonary bypass was higher in the vacuum group than in the gravity group (21.5 ± 7.3 vs 11.1 ± 7.1 mg/dl, P = 0.0284). Operative mortality and morbidity did not differ significantly between the groups. We found vacuum-assisted venous drainage to be a safe, simple, and effective technique in cases of minimally invasive cardiac surgery. However, there is a potential risk of hemolysis and air embolism, as shown in our findings and previous reports. [ABSTRACT FROM AUTHOR]

The NCR promoter (PNCR) from soybean chlorotic mottle virus (SoyCMV) was used to express the selectable marker, neomycin phosphotransferase ( nptII) gene, in Agrobacterium-mediated transformation of both monocot (rice) and dicot (tobacco) plants. A multi-cloning site for insertion of a gene of interest into the binary vector pTN is located proximal to the right border region of T-DNA. When chimeric genes under the control of other strong promoters were located in a head-to-head orientation to the PNCR-nptII gene, kanamycin-resistant tobacco shoots were generated more efficiently than when using the original pTN vectors. This suggests that the enhancer-like sequences in the promoters adjacent to PNCR may promote expression of the PNCR-nptII gene. [ABSTRACT FROM AUTHOR]

A fermionic analogue of the Groenwald-van Hove theorem is studied within the Kostant-Sternberg framework for the BRST ghosts. In gauge theories with semi-simple Lie groups, the BRST generator evades the fermionic version of Groenwald-van Hove theorem and inherits the nilpotency of the classical BRST charge mainly because of the particular structure of the classical charge, although the homomorphic property between the super-commutator and the super-Poisson bracket is problematical from the viewpoint of the theorem in quantization of cubic polynomials like the BRST charge. Avoiding the theorem is possibly one of the restrictions on the BRST charge in its construction in general constrained systems with the BRST generator involving ghost powers of order higher than three. [ABSTRACT FROM AUTHOR]