Whose Algorithm Says So

Financial advisors seek to accurately measure individuals' risk preferences and provide sound personalized investment advice. Both advice tasks are increasingly offered through automated online technologies. Little is known, however, about what drives individuals' acceptance of such automated financial advice and, from a consumer point of view, which firms may be best positioned to provide such advice. We generate novel insights on these questions by conducting a real-world empirical study using an interactive automated online tool that employs an innovative computer algorithm to build pension investment profiles, the “Pension Builder,” and a large, representative sample. We focus on the role that two key firm characteristics have on consumer acceptance of pension investment advice generated by computer algorithms running on automated interactive online tools: profit orientation and role in the sales channel. We find that consumers' perceptions of trust and expertise of the firm providing the automated advice are important drivers of advice acceptance (besides a strong impact of the satisfaction with the consumer–online tool interaction), and that these constructs themselves are clearly influenced by the for-profit vs. not-for-profit orientation and the product provider vs. advisor only role in the sales channel of the firm pr

How many days are needed to estimate wrist-worn accelerometry-assessed physical activity during the second trimester in pregnancy?

Background Objective methods to measure physical activity (PA) can lead to better cross-cultural comparisons, monitoring temporal PA trends, and measuring the effect of interventions. However, when applying this technology in field-work, the accelerometer data processing is prone to methodological issues. One of the most challenging issues relates to standardizing total wear time to provide reliable data across participants. It is generally accepted that at least 4 complete days of accelerometer wear represent a week for adults. It is not known if this same assumption holds true for pregnant women. Aim We assessed the optimal number of days needed to obtain reliable estimates of overall PA and moderate-to-vigorous physical activity (MVPA) during the 2nd trimester in pregnancy using a raw triaxial wrist-worn accelerometer. Methods Cross-sectional analyses were carried out in the antenatal wave of the 2015 Pelotas (Brazil) Birth Cohort Study. Participants wore the wrist ActiGraph wGT3X-BT accelerometer for seven consecutive days. The daily average acceleration, which indicated overall PA, was measured as milli-g (mg), and time spent in MVPA (minutes/day) was analyzed in 5-minute bouts. ANOVA and Kruskal-Wallis tests were used to compare variability across days of the week. Bland-Altman plots and the Spearman-Brown Prophecy Formula were applied to determine the reliability coefficient associated with one to seven days of measurement. Results Among 2,082 pregnant women who wore the accelerometer for seven complete days, overall and MVPA were lower on Sundays compared to other days of the week. Reliability of > = 0.80 to evaluate overall PA was reached with at least three monitoring days, whereas seven days were needed to estimate reliable measures of MVPA. Conclusions Our findings indicate that obtaining one week of accelerometry in adults is appropriate for pregnant women, particularly to obtain differences on weekend days and reliably estimate overall PA and MVPA

Analysis Of Maximal Isometric Force And Emg Signal In Lower Limb Exercise [análise Da Força Isométrica Máxima E Do Sinal De Emg Em Exercícios Para Os Membros Inferiors]

The aim of this study was to compare maximal isometric force (MIF) and the electrical activity of the vastus medialis, vastus lateralis, rectus femoris, gluteus maximus and biceps femoris long head muscles between maximal voluntary contractions (MVC) performed at different joint angles, and to identify the most suitable positions to normalize the electromyography (EMG) signals from each of these muscles when they are activated under dynamic conditions. Ten men ranging in age from 20 to 30 years, who were familiar with strength training exercise, were studied. MVC at different joint angles of the knee extensors and flexors (0°, 60°, 90°) and hip extensors (-30°, 0°, 60°) and flexors (90°, 120°) were tested. The MIF values differed significantly between the 60° knee flexion and 60° and 90° knee extension positions (p0.05). Significantly higher EMG values were only observed for the rectus femoris muscle at 90° knee extension (p0.05). These results suggest that the 60° knee joint flexion position is the most suitable for assessment of knee extension and flexion MIF, and that all positions tested in this study are suitable for the assessment of hip flexion and extension.136429435Basmajian, J.V., de Luca, C.J., (1985) Muscles Alive: Their Functions Revealed by Electromyography, , Baltimore: Williams and Wilkinsde Luca, C.J., The use of surface electromyography in biomechanics (1997) J Appl Biomech, 13, pp. 135-163Macdonald, J.H., Farina, D., Marcora, S.M., Response of Electromyography Variables during Incremental and Fatiguing Cycling (2008) Med Sci Sports Exerc, 40, pp. 335-344Onishi, H., Yagi, R., Akasaka, K., Momose, K., Ihashi, K., Handa, Y., Relationship between EMG signals and force in human vastus lateralis muscle using multiple bipolar wire electrodes (2000) J Electromyogr Kinesiol, 10, pp. 59-67Soderberg, G.L., Knutson, L.N., A Guide for Use and Interpretation of Kinesiology Electromyographic Data (2000) Phys Ther, 80 (5), pp. 585-598Stashuk, D., EMG signal decomposition: How can it be accomplished and used? 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Diminishing benefits of urban living for children and adolescents’ growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified. © 2023, The Author(s)

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions. © Copyright