Robotic Table Tennis: A Case Study into a High Speed Learning System

We present a deep-dive into a real-world robotic learning system that, in previous work, was shown to be capable of hundreds of table tennis rallies with a human and has the ability to precisely return the ball to desired targets. This system puts together a highly optimized perception subsystem, a high-speed low-latency robot controller, a simulation paradigm that can prevent damage in the real world and also train policies for zero-shot transfer, and automated real world environment resets that enable autonomous training and evaluation on physical robots. We complement a complete system description, including numerous design decisions that are typically not widely disseminated, with a collection of studies that clarify the importance of mitigating various sources of latency, accounting for training and deployment distribution shifts, robustness of the perception system, sensitivity to policy hyper-parameters, and choice of action space. A video demonstrating the components of the system and details of experimental results can be found at https://youtu.be/uFcnWjB42I0.Comment: Published and presented at Robotics: Science and Systems (RSS2023

COLLAGENASE IN SJOGRENS-SYNDROME

KONTTINEN YT, KANGASPUNTA P, LINDY O, et al. COLLAGENASE IN SJOGRENS-SYNDROME. ANNALS OF THE RHEUMATIC DISEASES. 1994;53(12):836-839.Objective-To study collagenase production in labial salivary glands in patients with Sjogren's syndrome (SS). Methods-Collagenases were localised in labial salivary glands by immunohistochemistry. Collagenase activity against triple helical type I collagen monomers in stimulated saliva was measured using sodium dodecyl sulphate polyacrylamide gel electrophoresis and laser densitometry; tissue inhibitor metalloproteinase (TIMP) was measured by enzyme Linked immunosorbent assay. Results-Cells containing collagenase of matrix metalloproteinase (MMP)-1 type were more frequent and more intensely staining in SS than in healthy glands. Only SS saliva contained functional enzyme (11.7 (6.8) x 10(-6) IU/1). Cells containing MMP-8 type neutrophil collagenase were not found in situ, which was in accordance with sialochemical findings/doxycycline inhibition studies. TIMP was found in both SS and normal saliva. Conclusions-Fibroblast, but not neutrophil type, collagenase is synthesised, secreted, and subsequently activated, but is not inhibited by TIMP in labial salivary glands or saliva in SS. Collagenase may destroy glandular and salivary duct tissue and perturb factors influencing the morphogenetic extracellular matrix

Constructing the ideal victim in the United States of America's annual trafficking in persons reports

Human trafficking as a global phenomenon continues to elude accurate quantitative measure, and remains a controversial policy domain significantly influenced by anecdotal evidence. Drawing on the policy analysis framework of Bacchi (1999; 2007) the problem representation of trafficking through narratives can be considered a direct antecedent of contemporary anti-human trafficking policy. This article explores the construction of human trafficking within the Trafficking in Persons Reports, published annually by the United States of America’s Department of State. An examination of the victim and offender narratives contained within the reports published between 2001 and 2012 demonstrates that human trafficking is predominantly represented as a crime committed by ideal offenders against idealized victims, consistent with Christie’s (1986) landmark criteria of ideal victimization. This representation of an ideal prototype has the potential to inform policy that diverts focus from the causative role of global socioeconomic injustice towards criminal justice policies targeting individual offenders