In this work, we present WALK-MAN, a humanoid platform that has been developed to operate in realistic unstructured environment, and demonstrate new skills including powerful manipulation, robust balanced locomotion, high-strength capabilities, and physical sturdiness. To enable these capabilities, WALK-MAN design and actuation are based on the most recent advancements of series elastic actuator drives with unique performance features that differentiate the robot from previous state-of-the-art compliant actuated robots. Physical interaction performance is benefited by both active and passive adaptation, thanks to WALK-MAN actuation that combines customized high-performance modules with tuned torque/velocity curves and transmission elasticity for high-speed adaptation response and motion reactions to disturbances. WALK-MAN design also includes innovative design optimization features that consider the selection of kinematic structure and the placement of the actuators with the body structure to maximize the robot performance. Physical robustness is ensured with the integration of elastic transmission, proprioceptive sensing, and control. The WALK-MAN hardware was designed and built in 11 months, and the prototype of the robot was ready four months before DARPA Robotics Challenge (DRC) Finals. The motion generation of WALK-MAN is based on the unified motion-generation framework of whole-body locomotion and manipulation (termed loco-manipulation). WALK-MAN is able to execute simple loco-manipulation behaviors synthesized by combining different primitives defining the behavior of the center of gravity, the motion of the hands, legs, and head, the body attitude and posture, and the constrained body parts such as joint limits and contacts. The motion-generation framework including the specific motion modules and software architecture is discussed in detail. A rich perception system allows the robot to perceive and generate 3D representations of the environment as well as detect contacts and sense physical interaction force and moments. The operator station that pilots use to control the robot provides a rich pilot interface with different control modes and a number of teleoperated or semiautonomous command features. The capability of the robot and the performance of the individual motion control and perception modules were validated during the DRC in which the robot was able to demonstrate exceptional physical resilience and execute some of the tasks during the competition

In this systematic review, it seems that LH is faster than OH for bilateral hernias, whereas there is no significant difference in terms of operative time for unilateral inguinal hernia repair. Recurrence rate is similar for both techniques. As for other complications such as wound infections, it is higher for OH compared with LH, especially in infants. A prospective comparative study is necessary on this topic to strongly support the results of our systematic review.

Quasinormal-mode treatment is extended to the description of scalar field behavior in one-dimensional photonic crystals. A one-dimensional photonic crystal is a particular configuration of an open cavity, where discontinuities of the refractive index give rise to field confinement. This paper presents, for a one-dimensional photonic crystal, a discussion about the completeness of the quasinormal-mode representation and, moreover, a discussion on the complex eigenfrequencies, as well as the corresponding field distribution. The concept of density of modes is also discussed in terms of quasinormal modes.

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We conclude that in clinical settings where laparoscopic surgical expertise and equipment are available and affordable, LA seems to be an effective and safe alternative to OA. Three out 9 centres participating in our survey perform LA in all patients with a suspicion of appendicitis. Our study shows that laparoscopy significantly reduces hospital stay in case of appendicitis and peritonitis and presents an extremely low conversion rate (1.6%) to open surgery. Laparoscopic transumbilical appendectomy (37.9%) in our series seems to be a simple option, even for less-skilled laparoscopic surgeons.

In children affected by VUR, open Cohen and LEVUR reported a higher success rate than STING procedure. However, Cohen procedure had a very long and painful hospital stay, more complications, more analgesic requirements compared to STING and LEVUR. Comparing the three techniques, it seems that LEVUR presents a high success rate similar to the Cohen procedure, but in addition, it presents the same advantages of STING procedure with no postoperative pain and a lower postoperative morbidity.

For pediatric patients with GERD, laparoscopic Nissen, Toupet, and Thal antireflux procedures yielded satisfactory results, and none of the approaches led to increased dysphagia. The 5% rate for intraoperative complications seems linked to the learning curve period. The authors consider the three procedures as extremely effective for the treatment of children with GERD, and they believe that the choice of one procedure over the other depends only on the surgeon's experience. Parental satisfaction with laparoscopic treatment was very high in all the three series.

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