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This paper presents an analytical model that quantifies the stress ratio between two test specimens for the same probability of failure based on the Weibull weakest link theory. The model takes into account the test specimen geometry, i.e., its shape and volume, and the related non-constant stress state along the specimen. The proposed model is a valuable tool for quantifying the effect of a change of specimen geometry on the probability of failure. This is essential to distinguish size scaling from the actual improvement in measured strength when specimen geometry is optimized, aiming for failure in the gauge section. For unidirectional carbon fibre composites with Weibull modulus m in the range 10–40, it can be calculated by the model that strength measured with a straight-sided specimen will be 1–2% lower than the strength measured with a specific waisted butterfly-shaped specimen solely due to the difference in test specimen shape and volume.  相似文献   
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Research on dietary intake and its determinants is crucial for an adequate response to the current epidemic of diet‐related non‐communicable chronic diseases. In order to respond to this challenge, the RICHFIELDS project was tasked with designing a research infrastructure (RI) that connects data on dietary intake of consumers in Europe, and its determinants, collected using apps and wearable sensors, from behavioural laboratories and experimental facilities and from other RIs. The main output of the project, an RI design, describes interfaces (portals) to collect data, a meta‐database and a data‐model to enable data linkage and sharing. The RICHFIELDS project comprises three phases, each consisting of three work packages, and an overarching methodological support work package. Phase 1 focused on data generated by consumers (e.g. collected by apps and sensors) relating to the purchase, preparation and consumption of food. Phase 2 focused on data generated by organisations such as businesses (e.g. retail data), government (e.g. procurement data) and experimental research facilities (e.g. virtual supermarkets). Phases 1 and 2 provided Phase 3 with insights on data types and design requirements, including the business models, data integration and management systems and governance and ethics. The final design will be used in the coming years to build an RI for the scientific research community, policy makers and businesses in Europe. The RI will boost interdisciplinary multi‐stakeholder research through harmonisation and integration of data on food behaviour.  相似文献   
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ObjectiveThe purpose of this study was to investigate the relationship between 12 work-related stressors and the occurrence of adverse events in an emergency department (ED).MethodsNurses and physicians, working in an ED at a Danish regional hospital, filled out a questionnaire on occurrence and emotional impact of 12 work-related stressors after each shift during a 4-week period. The questionnaire also instructed the participants to describe any adverse events that they were involved in during the shift.ResultsTwo hundred fourteen adverse events were reported during the 979 studied shifts. During the same period, only 27 adverse events were reported to the mandatory national reporting system, and only 10 of these were duplicates. A high variability of stressors and emotional impact among the different groups of participants was found. Linear regression analysis showed an association between involvement in adverse events and the occurrence and emotional impact of stressors across groups, whereas no significant association was found for age, seniority, shift type, or length.ConclusionThe study showed an association between the occurrence and impact of 12 work-related stressors and involvement in adverse events across the groups of participants. Furthermore, the study showed that most adverse events were not reported to the mandatory national reporting system.  相似文献   
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The burden of senescent cells (SnCs), which do not divide but are metabolically active and resistant to death by apoptosis, is increased in older adults and those with chronic diseases. These individuals are also at the greatest risk for morbidity and mortality from SARS-CoV-2 infection. SARS-CoV-2 complications include cytokine storm and multiorgan failure mediated by the same factors as often produced by SnCs through their senescence-associated secretory phenotype (SASP). The SASP can be amplified by infection-related pathogen-associated molecular profile factors. Senolytic agents, such as Fisetin, selectively eliminate SnCs and delay, prevent, or alleviate multiple disorders in aged experimental animals and animal models of human chronic diseases, including obesity, diabetes, and respiratory diseases. Senolytics are now in clinical trials for multiple conditions linked to SnCs, including frailty; obesity/diabetes; osteoporosis; and cardiovascular, kidney, and lung diseases, which are also risk factors for SARS-CoV-2 morbidity and mortality. A clinical trial is underway to test if senolytics decrease SARS-CoV-2 progression and morbidity in hospitalized older adults. We describe here a National Institutes of Health-funded, multicenter, placebo-controlled clinical trial of Fisetin for older adult skilled nursing facility (SNF) residents who have been, or become, SARS-CoV-2 rtPCR-positive, including the rationale for targeting fundamental aging mechanisms in such patients. We consider logistic challenges of conducting trials in long-term care settings in the SARS-CoV-2 era, including restricted access, consent procedures, methods for obtaining biospecimens and clinical data, staffing, investigational product administration issues, and potential solutions for these challenges. We propose developing a national network of SNFs engaged in interventional clinical trials.  相似文献   
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Guardianship may pose an ethical dilemma for physicians, who must balance protecting vulnerable patients from potential safety concerns with respecting their autonomy. Older adults with dementia are particularly susceptible to loss of independence and the ability to participate in medical decision making. To have the capacity for medical decision making, individuals must understand relevant information, appreciate their circumstances, demonstrate reasoning, and express a consistent choice free from coercion. Although capacity assessments are usually task-specific, geriatricians and other specialists may be asked to comment on capacity more globally. These determinations may be used to support a Petition for the Appointment of a Guardian of a Legally Incapacitated Adult, the legal process of pursuing guardianship in probate court. Assigned guardians may be known to the incapacitated individual (e.g., a family member or friend) or may be professional guardians with no prior relationship to the ward. Guardians are encouraged to use substituted decision-making, taking into account the ward's previously expressed values and preferences. Although a number of viable alternatives to guardianship exist, numerous systemic barriers may prevent these from being fully explored. The ongoing need for guardianship should be periodically revisited and reassessed. Data about guardians and wards is shockingly sparse, as there are no centralized databases. Laws and regulations for guardianships vary significantly between states. Physicians can serve as important allies and advocates for patients with cognitive impairment at risk of incapacity, can help preserve their autonomy for as long as possible, and ensure appropriate protections are in place if the patient does lose their decision-making ability.  相似文献   
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Metabolic Brain Disease - Hepatic encephalopathy (HE) is cerebral dysfunction caused by liver failure and inflicts 30-40% of patients with liver cirrhosis during their disease course. Clinically...  相似文献   
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