Grounding Hindsight Instructions in Multi-Goal Reinforcement Learning for Robotics

This paper focuses on robotic reinforcement learning with sparse rewards for natural language goal representations. An open problem is the sample-inefficiency that stems from the compositionality of natural language, and from the grounding of language in sensory data and actions. We address these issues with three contributions. We first present a mechanism for hindsight instruction replay utilizing expert feedback. Second, we propose a seq2seq model to generate linguistic hindsight instructions. Finally, we present a novel class of language-focused learning tasks. We show that hindsight instructions improve the learning performance, as expected. In addition, we also provide an unexpected result: We show that the learning performance of our agent can be improved by one third if, in a sense, the agent learns to talk to itself in a self-supervised manner. We achieve this by learning to generate linguistic instructions that would have been appropriate as a natural language goal for an originally unintended behavior. Our results indicate that the performance gain increases with the task-complexity.Comment: Preprint ICDL 202

Influence of High BMI on Functional Outcome After Total Hip Arthroplasty

Background: High body mass index (BMI) is associated with diseases of the hip joint and subsequent total hip arthroplasty (THA). Less is known about the effects of BMI on the functional postoperative status after THA in obese patients. The purpose of this study was therefore to quantify the role of high preoperative BMI on long-term pain status and functional outcome after THA. Methods: In a multi-center cohort, study data of 20,553 primary THAs (18,968 patients) and 43,562 postoperative clinical examinations were analyzed for a follow-up period of up to 15years. Patients were classified into three BMI groups (normal weight <25kg/m2, overweight 25 to <30kg/m2, and obese ≥30kg/m2), and pain status and functional outcome were compared accordingly. Results: High preoperative BMI is associated to an almost perfect dose-effect relationship with decreased ambulation during a follow-up period of 15years, but pain relief of THA is equally efficient for all BMI groups. Conclusion: Overweight and obesity are modifiable risk factors that may warrant physicians giving recommendations to patients before or after THA, to improve postoperative functional outcome qualit

A cautionary note on thermal runaway reactions in mixtures of 1-alkyl-3-methylimidazolium ionic liquids and N-methylmorpholine-N-oxide

Nicht verfügbarN-Methylmorpholine-N-oxide (NMMO) cannot be completely separated by extraction from mixtures with common 1,3-dialkylimidazolium ionic liquids (ILs) due to strong ionic interactions between the two components. At elevated temperatures, above approx. 90 C, especially under dry conditions and in the presence of acid, alkylating or acylating agents, remaining NMMO in ILs tends to undergo autocatalytic degradation. This is a highly exothermic, unstoppable process that results in explosions, flames, and complete charring of the reaction mixtures. Thus, caution must be exercised when drying or heating ILs that were in previous contact with NMMO, and the absence of amine oxide must be confirmed to avoid potential danger.(VLID)192930

High incidence of medication documentation errors in a Swiss university hospital due to the handwritten prescription process

BACKGROUND: Medication errors have been reported to be a leading cause of death in hospitalized patients. In this study we focused on identifying and quantifying errors in the handwritten drug ordering and dispensing documentation processes which could possibly lead to adverse drug events. METHODS: We studied 1,934 ordered agents (165 consecutive patients) retrospectively for medication documentation errors. Errors were categorized into: Prescribing errors, transcription errors and administration documentation errors on the nurses' medication lists. The legibility of prescriptions was analyzed to explore its possible influence on the error rate in the documentation process. RESULTS: Documentation errors occurred in 65 of 1,934 prescribed agents (3.5%). The incidence of patient charts showing at least one error was 43%. Prescribing errors were found 39 times (37%), transcription errors 56 times (53%), and administration documentation errors 10 times (10%). The handwriting readability was rated as good in 2%, moderate in 42%, bad in 52%, and unreadable in 4%. CONCLUSIONS: This study revealed a high incidence of documentation errors in the traditional handwritten prescription process. Most errors occurred when prescriptions were transcribed into the patients' chart. The readability of the handwritten prescriptions was generally bad. Replacing the traditional handwritten documentation process with information technology could potentially improve the safety in the medication process

Relationship between sources and patterns of VOCs in indoor air

AbstractPeople spend most of their daytime in indoor environments. Their activities influence the composition of the indoor air by emitting volatile organic compounds (VOCs). The increasing number of different VOCs became the focus of attention in recent years as the question arises from the relationship between exposure to air pollutants and diseases. The present study of flats in Leipzig (Germany) is based on measurements of 60 different VOCs and is unique in the field of indoor air quality due to its enormous size of samples (n=2 242) and questionnaire data. The main purpose of our analysis was to identify the sources and patterns that characterize airborne VOCs in occupied flats. We combined two methods, principal components analysis (PCA) and non–negative matrix factorization (NMF), to assign compounds to their origin and to understand the coinstantaneous existence of several VOCs. PCA clustering provided a source apportionment and yielded 10 principal components (PCs) with an explained variance of 72%. However, real indoor air quality is often affected by combined sources. NMF reveals characteristic compositions of VOCs in indoor environments and emphasizes that constantly recurring structures are not single sources, but rather fusions of them, so called patterns. Interpreting these sources, we realized that homes were strongly influenced by ventilation, human activities, furnishings, natural processes (such as solar radiation) or their combinations. The very large set of samples and the combination with questionnaires applied on this comprehensive assessment of VOCs allows generalizing the results to homes in middle–scale cities with minor industrial pollution. As a conclusion, single VOC–dose–response relationships are inopportune for situations when indoor sources occur in combination. Further studies are necessary to assess associated health risks