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This paper opens up with the definition of some fatigue criteria for multiaxial cyclic loading. This introduces the problem of the prevalence of random multiaxial loading in the service environment of mechanical components. A survey of fatigue criteria found in the literature is presented with a comparative analysis. This analysis suggests that the selection of a fatigue criterion be based on whether or not the principal directions of stress tensors are mobile or invariable with time. The use of these fatigue models to predict the life of a component subjected to random multiaxial load is presented as well. The performance of each of these models is evaluated with test data obtained from a biaxial amplitude fatigue test. Improvements on these models are suggested and analyzed with the aim of developing the best representation of the influence of compressive stresses as well as stress gradients useful in mechanical design. [ABSTRACT FROM AUTHOR]

This paper presents optimization methods for the computation of fatigue life in multiaxial fatigue. It begins with the definition of some fatigue criteria for multiaxial cyclic loading. This introduces the problem of the prevalence of random multiaxial loading in the service environment of mechanical components. Two types of fatigue criteria found in the literature are presented. A comparative analysis of these models is also presented: Robert Criterion and Fogué Criterion. The use of these fatigue models to predict the life of a component subjected to random multiaxial load is presented as well as the performance of each of these models is evaluated with test data obtained from a biaxial amplitude fatigue test. Finally, an analysis, which is aimed at reducing the computation time associated with the criteria, is presented. This analysis suggests that a valuable fatigue evaluation tool is now available to the mechanical design industry. [ABSTRACT FROM AUTHOR]

Background: The AIRE operational project will evaluate the implementation of the routine Pulse Oximeter (PO) use in the integrated management of childhood illness (IMCI) strategy for children under-5 in primary health care centers (PHC) in West Africa. The introduction of PO should promote the accurate identification of hypoxemia (pulse blood oxygen saturation Sp02 < 90%) among all severe IMCI cases (respiratory and non-respiratory) to prompt their effective case management (oxygen, antibiotics and other required treatments) at hospital. We seek to understand how the routine use of PO integrated in IMCI outpatients works (or not), for whom, in what contexts and with what outcomes., Methods: The AIRE project is being implemented from 03/2020 to 12/2022 in 202 PHCs in four West African countries (Burkina Faso, Guinea, Mali, Niger) including 16 research PHCs (four per country). The research protocol will assess three complementary components using mixed quantitative and qualitative methods: a) context based on repeated cross-sectional surveys: baseline and aggregated monthly data from all PHCs on infrastructure, staffing, accessibility, equipment, PO use, severe cases and care; b) the process across PHCs by assessing acceptability, fidelity, implementation challenges and realistic evaluation, and c) individual outcomes in the research PHCs: all children under-5 attending IMCI clinics, eligible for PO use will be included with parental consent in a cross-sectional study. Among them, severe IMCI cases will be followed in a prospective cohort to assess their health status at 14 days. We will analyze pathways, patterns of care, and costs of care., Discussion: This research will identify challenges to the systematic implementation of PO in IMCI consultations, such as health workers practices, frequent turnover, quality of care, etc. Further research will be needed to fully address key questions such as the best time to introduce PO into the IMCI process, the best SpO2 threshold for deciding on hospital referral, and assessing the cost-effectiveness of PO use. The AIRE research will provide health policy makers in West Africa with sufficient evidence on the context, process and outcomes of using PO integrated into IMCI to promote scale-up in all PHCs., Trial Registration: Trial registration number: PACTR202206525204526 retrospectively registered on 06/15/2022., (© 2022. The Author(s).)

Background: The use of mobile technology in health care (mobile health [mHealth]) could be an innovative way to improve health care, especially for increasing retention in HIV care and adherence to treatment. However, there is a scarcity of studies on mHealth among people living with HIV (PLHIV) in West and Central Africa., Objective: The aim of this study was to assess the acceptability of an mHealth intervention among PLHIV in three countries of West Africa., Methods: A cross-sectional study among PLHIV was conducted in 2017 in three francophone West African countries: Côte d'Ivoire, Burkina Faso, and Togo. PLHIV followed in the six preselected HIV treatment and care centers, completed a standardized questionnaire on mobile phone possession, acceptability of mobile phone for HIV care and treatment, preference of mobile phone services, and phone sharing. Descriptive statistics and logistic regression were used to describe variables and assess factors associated with mHealth acceptability., Results: A total of 1131 PLHIV-643 from Côte d'Ivoire, 239 from Togo, and 249 from Burkina Faso-participated in the study. Median age was 44 years, and 76.1% were women (n=861). Almost all participants owned a mobile phone (n=1107, 97.9%), and 12.6% (n=140) shared phones with a third party. Acceptability of mHealth was 98.8%, with the majority indicating their preference for both phone calls and text messages. Factors associated with mHealth acceptability were having a primary school education or no education (adjusted odds ratio=7.15, 95% CI 5.05-10.12; P<.001) and waiting over one hour before meeting a medical doctor on appointment day (adjusted odds ratio=1.84, 95% CI 1.30-2.62; P=.01)., Conclusions: The use of mHealth in HIV treatment and care is highly acceptable among PLHIV and should be considered a viable tool to allow West and Central African countries to achieve the Joint United Nations Programme on HIV/AIDS 90-90-90 goals., (©Phillipe Lepère, Yélamikan Touré, Alexandra M Bitty-Anderson, Simon P Boni, Gildas Anago, Boris Tchounga, Pendadiago Touré, Albert Minga, Eugène Messou, Guillaume Kanga, Serge Koule, Armel Poda, Alexandra Calmy, Didier K Ekouevi, Patrick A Coffie. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 13.11.2019.)