Limb Stiffness Improvement of the Robot WAREC-1R for a Faster and Stable New Ladder Climbing Gait

Ladder climbing is a relatively new but practical locomotion style for robots. Unfortunately, due to their size and weight, ladder climbing by human-sized robots developed so far is struggling with the speedup of ladder climbing motion itself. Therefore, in this paper, a new ladder climbing gait for the robot WAREC-1R is proposed by the authors, which is both faster than the former ones and stable. However, to realize such a gait, a point that has to be taken into consideration is the deformation caused by the self-weight of the robot. To deal with this issue, extra hardware (sensor) and software (position and force control) systems and extra time for sensing and calculation were required. For a complete solution without any complicated systems and time only for deformation compensation, limb stiffness improvement plan by the minimal design change of mechanical parts of the robot is also proposed by the authors, with a thorough study about deformation distribution in the robot. With redesigned parts, ladder climbing experiments by WAREC-1R proved that both the new ladder climbing gait and the limb stiffness improvement are successful, and the reduced deformation is very close to the estimated value as well.

Clinical outcomes of patients with chronic hepatitis C after generic direct-acting antiviral treatments in Vietnam: A retrospective analysis

Objective:To evaluate the outcomes of generic direct-acting antiviral treatments for chronic hepatitis C in Vietnam.Methods:The medical records of 522 patients(median 45 years;Female,25.3%)with chronic hepatitis C treated at a tertiary hospital in northern Vietnam in 2016 were retrospectively reviewed.Results:Female patients were significantly older than male patients(median 52,IQR 41-59 vs.43 years,IQR:39-55;P<0.001).Among 522 patients,49.4%were infected with hepatitis C virus(HCV)genotype 6,followed by 1 a(19.0%),1 b(13.0%),and 3(5.9%).Coinfection with hepatitis B virus or human immunodeficiency virus was noted in 5.8%and 3.1%of patients,respectively.Patients were treated with ledipasvir/sofosbuvir with or without ribavirin(70.9%),sofosbuvir/pegylated-interferon+ribavirin(13.2%),daclatasvir/sofosbuvir with or without ribavirin(12.5%),or sofosbuvir/ribavirin(3.4%),and 96.4%(n=503)completed the direct-acting antiviral treatment.No patient discontinued treatment due to adverse event(s).A sustained virologic response 12 weeks after the end of the treatment(SVR12)was evaluated in 62.6%of patients.Overall sustained virologic response 12 weeks after the end of the treatment was 98.7%regardless of HCV genotypes or direct-acting antiviral regimens.The severity of liver stiffness was significantly decreased from 10.2 to 6.3 kilopascals measured by transient elastography by the treatment(P<0.001).Among patients who completed the directacting antiviral treatment,17.7%returned for further follow-ups after SVR12.Conclusions:In Vietnam,the current generic direct-acting antiviral treatment for chronic hepatitis C was effective regardless of HCV genotypes and direct-acting antiviral regimens with the attenuation of liver stiffness.It is feasible to implement direct-acting antiviral treatment to cure chronic hepatitis C patients at any liver fibrosis stages in Vietnam.