322 research outputs found

    Simulationsgestützte Lösung von Deadlocks bei fahrerlosen Transportsystemen mit Hilfe von Deep Reinforcement Learning

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    This paper discusses the use of deep reinforcement learning to resolve deadlocks in material flow systems with automated guided vehicles (AGVs). The paper proposes a strategy for dealing with deadlocks based on a single Agent reinforcement learning approach (SARL). The agent will find the optimal solution strategy in real time. The proposed approach is evaluated using a material flow simulation for a real use case in industry. The effectiveness in reducing the occurrence of deadlocks as well as the number of collisions in the system is demonstrated. This study highlights the potential of deep reinforcement learning for improving the performance and efficiency of material flow systems with AGVs

    It takes two to tango: improving patient referrals from the emergency department to inpatient clinicians

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    Background: The transfer of responsibility for patient care across clinical specialties is a complex process. Published and anecdotal data suggest that referrals often fail to meet the needs of one or both parties and that patient focus can be lost during the process. Little is known about the Australian situation. Methods: To obtain a more complete understanding of the referral process, including the nature of communication in an Australian context, we conducted semistructured interviews in a convenience sample of 25 volunteers. Two established strategies for analyzing qualitative data were used. Results: All respondents considered the following information essential components of a referral: an account of the patient’s current condition, a working diagnosis or problem statement and history of the presenting concern, key test results or tests awaiting results, a potential management plan, and any special characteristics of the patient. Respondents acknowledged implied, if not literal, power to accept or reject an emergency department (ED) referral and said the imbalance of power was reinforced when the ED physician was junior to the inpatient clinician. Respondents also noted that in addition to the predominant organizational culture, an independent culture is associated with specific shifts. Foremost among the nonclinical aspects of a referral considered to be important was the timeliness of the contact made to achieve the transition. Respondents also said the success of a referral depended on the speaking and listening abilities of all parties. The individual’s motivation to accept or reject a referral can also have an impact on communication. Conclusion: Respondents attributed the difficulty of negotiating the transfer of a patient’s care across the ED and inpatient interface to three distinct factors: variations in the clinical information required, the culture of the organization and of the clinical team in which the transaction takes place, and the characteristics of the individuals involved in the process. Improving communication skills has the potential to improve patient outcomes

    Polymorphisms in the circadian expressed genes PER3 and ARNTL2 are associated with diurnal preference and GNβ3 with sleep measures

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    Sleep and circadian rhythms are intrinsically linked, with several sleep traits, including sleep timing and duration, influenced by both sleep homeostasis and the circadian phase. Genetic variation in several circadian genes has been associated with diurnal preference (preference in timing of sleep), although there has been limited research on whether they are associated with other sleep measurements. We investigated whether these genetic variations were associated with diurnal preference (Morningness-Eveningness Questionnaire) and various sleep measures, including: the global Pittsburgh Sleep Quality index score; sleep duration; and sleep latency and sleep quality. We genotyped 10 polymorphisms in genes with circadian expression in participants from the G1219 sample (n = 966), a British longitudinal population sample of young adults. We conducted linear regressions using dominant, additive and recessive models of inheritance to test for associations between these polymorphisms and the sleep measures. We found a significant association between diurnal preference and a polymorphism in period homologue 3 (PER3) (P < 0.005, recessive model) and a novel nominally significant association between diurnal preference and a polymorphism in aryl hydrocarbon receptor nuclear translocator-like 2 (ARNTL2) (P < 0.05, additive model). We found that a polymorphism in guanine nucleotide binding protein beta 3 (GNβ3) was associated significantly with global sleep quality (P < 0.005, recessive model), and that a rare polymorphism in period homologue 2 (PER2) was associated significantly with both sleep duration and quality (P < 0.0005, recessive model). These findings suggest that genes with circadian expression may play a role in regulating both the circadian clock and sleep homeostasis, and highlight the importance of further studies aimed at dissecting the specific roles that circadian genes play in these two interrelated but unique behaviours

    Marshall Space Flight Center solid waste characterization and recycling improvement study: General office and laboratory waste, scrap metal, office and flight surplus

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    The primary objectives of the study were to characterize the solid waste stream for MSFC facilities in Huntsville, Alabama, and to evaluate their present recycling program. The purpose of the study was to determine if improvements could be made in terms of increasing quantities of the present commodities collected, adding more recyclables to the program, and streamlining or improving operational efficiency. In conducting the study, various elements were implemented. These included sampling and sorting representative samples of the waste stream; visually inspecting each refuse bin, recycle bin, and roll-off; interviewing employees and recycling coordinators of other companies; touring local material recycling facilities; contacting experts in the field; and performing a literature search

    Involvement of phosphoinositide 3-kinase and Akt in the induction of muscle protein degradation by proteolysis-inducing factor

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    In the present study the role of Akt/PKB (protein kinase B) in PIF- (proteolysis-inducing factor) induced protein degradation has been investigated in murine myotubes. PIF induced transient phosphorylation of Akt at Ser(473) within 30 min, which was attenuated by the PI3K (phosphoinositide 3-kinase) inhibitor LY294002 and the tyrosine kinase inhibitor genistein. Protein degradation was attenuated in myotubes expressing a dominant-negative mutant of Akt (termed DNAkt), compared with the wild-type variant, whereas it was enhanced in myotubes containing a constitutively active Akt construct (termed MyrAkt). A similar effect was observed on the induction of the ubiquitin-proteasome pathway. Phosphorylation of Akt has been linked to up-regulation of the ubiquitin-proteasome pathway through activation of NF-kappaB (nuclear factor kappaB) in a PI3K-dependent process. Protein degradation was attenuated by rapamycin, a specific inhibitor of mTOR (mammalian target of rapamycin), when added before, or up to 30 min after, addition of PIF. PIF induced transient phosphorylation of mTOR and the 70 kDa ribosomal protein S6 kinase. These results suggest that transient activation of Akt results in an increased protein degradation through activation of NF-kappaB and that this also allows for a specific synthesis of proteasome subunits

    Epidemiology, prehospital care and outcomes of patients arriving by ambulance with dyspnoea: An observational study

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    Background: This study aimed to determine epidemiology and outcome for patients presenting to emergency departments (ED) with shortness of breath who were transported by ambulance. Methods: This was a planned sub-study of a prospective, interrupted time series cohort study conducted at three time points in 2014 and which included consecutive adult patients presenting to the ED with dyspnoea as a main symptom. For this sub-study, additional inclusion criteria were presentation to an ED in Australia or New Zealand and transport by ambulance. The primary outcomes of interest are the epidemiology and outcome of these patients. Analysis was by descriptive statistics and comparisons of proportions. Results: One thousand seven patients met inclusion criteria. Median age was 74 years (IQR 61-68) and 46.1 % were male. There was a high rate of co-morbidity and chronic medication use. The most common ED diagnoses were lower respiratory tract infection (including pneumonia, 22.7 %), cardiac failure (20.5%) and exacerbation of chronic obstructive pulmonary disease (19.7 %). ED disposition was hospital admission (including ICU) for 76.4 %, ICU admission for 5.6 % and death in ED in 0.9 %. Overall in-hospital mortality among admitted patients was 6.5 %. Discussion: Patients transported by ambulance with shortness of breath make up a significant proportion of ambulance caseload and have high comorbidity and high hospital admission rate. In this study, >60 % were accounted for by patients with heart failure, lower respiratory tract infection or COPD, but there were a wide range of diagnoses. This has implications for service planning, models of care and paramedic training. Conclusion: This study shows that patients transported to hospital by ambulance with shortness of breath are a complex and seriously ill group with a broad range of diagnoses. Understanding the characteristics of these patients, the range of diagnoses and their outcome can help inform training and planning of services
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