The utility of behavioral biometrics in user authentication and demographic characteristic detection: a scoping review.

BACKGROUND: Objective measures of screen time are necessary to better understand the complex relationship between screen time and health outcomes. However, current objective measures of screen time (e.g., passive sensing applications) are limited in identifying the user of the mobile device, a critical limitation in children's screen time research where devices are often shared across a family. Behavioral biometrics, a technology that uses embedded sensors on modern mobile devices to continuously authenticate users, could be used to address this limitation. OBJECTIVE: The purpose of this scoping review was to summarize the current state of behavioral biometric authentication and synthesize these findings within the scope of applying behavioral biometric technology to screen time measurement. METHODS: We systematically searched five databases (Web of Science Core Collection, Inspec in Engineering Village, Applied Science & Technology Source, IEEE Xplore, PubMed), with the last search in September of 2022. Eligible studies were on the authentication of the user or the detection of demographic characteristics (age, gender) using built-in sensors on mobile devices (e.g., smartphone, tablet). Studies were required to use the following methods for authentication: motion behavior, touch, keystroke dynamics, and/or behavior profiling. We extracted study characteristics (sample size, age, gender), data collection methods, data stream, model evaluation metrics, and performance of models, and additionally performed a study quality assessment. Summary characteristics were tabulated and compiled in Excel. We synthesized the extracted information using a narrative approach. RESULTS: Of the 14,179 articles screened, 122 were included in this scoping review. Of the 122 included studies, the most highly used biometric methods were touch gestures (n = 76) and movement (n = 63), with 30 studies using keystroke dynamics and 6 studies using behavior profiling. Of the studies that reported age (47), most were performed exclusively in adult populations (n = 34). The overall study quality was low, with an average score of 5.5/14. CONCLUSION: The field of behavioral biometrics is limited by the low overall quality of studies. Behavioral biometric technology has the potential to be used in a public health context to address the limitations of current measures of screen time; however, more rigorous research must be performed in child populations first. SYSTEMATIC REVIEW REGISTRATION: The protocol has been pre-registered in the Open Science Framework database ( https://doi.org/10.17605/OSF.IO/92YCT ).

Comparison of energy intake assessed by image-assisted food records to doubly labelled water in adolescents with intellectual and developmental disabilities: a feasibility study.

BACKGROUND: There are currently no validated methods for energy intake assessment in adolescents with intellectual and developmental disabilities (IDD). The purpose of this study was to determine the feasibility of collecting 3-day image-assisted food records (IARs) and doubly labelled water (TDEEDLW ) data in adolescents with IDD and to obtain preliminary estimates of validity and reliability for energy intake estimated by IAR. METHODS: Adolescents with IDD completed a 14-day assessment of mean daily energy expenditure using doubly labelled water. Participants were asked to complete 3-day IARs twice during the 14-day period. To complete the IAR, participants were asked to fill out a hard copy food record over three consecutive days (two weekdays/one weekend day) and to take before and after digital images of all foods and beverages consumed using an iPad tablet provided by the study. Energy intake from the IAR was calculated using Nutrition Data System for Research. Mean differences, intraclass correlations and Bland-Altman limits of agreement were performed. RESULTS: Nineteen adolescents with IDD, mean age 15.1 years, n = 6 (31.6%) female and n = 6 (31.6%) ethnic/racial minorities, enrolled in the trial. Participants successfully completed their 3-day food records and self-collected doubly labelled water urine samples for 100% of required days. Images were captured for 67.4 ± 30.1% of all meals recorded at assessment 1 and 72.3 ± 29.5% at assessment 2. The energy intake measured by IAR demonstrated acceptable test-retest reliability (intraclass correlation = 0.70). On average, IAR underestimated total energy intake by -299 ± 633 kcal/day (mean per cent error = -9.6 ± 22.2%); however, there was a large amount of individual variability in differences between the IAR and TDEEDLW (range = -1703 to 430). CONCLUSIONS: The collection of IAR and TDEEDLW is feasible in adolescents with IDD. While future validation studies are needed, the preliminary estimates obtained by this study suggest that in adolescents with IDD, the IAR method has acceptable reliability and may underestimate energy intake by ~9%.

Exploring the effectiveness of an 18-month weight management intervention in adults with Down syndrome using propensity score matching.

BACKGROUND: Down syndrome (DS) is one of the most common birth defects in the USA associated with high levels of overweight and obesity. Unique characteristics of adults with DS that may contribute to the high levels of obesity are high rates of hypothyroidism, poor muscle tone, altered gait and lower resting metabolic rate. Due to these factors, it is unknown if the same weight management interventions that are effective in adults with intellectual or developmental disability (IDD) without DS are as effective in those with DS. Therefore, the purpose of this secondary analysis was to compare changes in weight, diet and physical activity between participants with DS-related and non-DS-related IDD participating in an 18-month weight management trial. METHODS: We used propensity score methods to adjust baseline variables of overweight/obese adults with and without DS participating in an 18-month effectiveness trial with 6 months weight loss and 12 months weight maintenance. Participants followed one of two reduced calorie diet plans, obtained 150 min of moderate-vigorous intensity physical activity (MVPA) per week, and logged dietary intake daily. A health educator held monthly at-home visits with participants and a caregiver to give feedback on intervention compliance. RESULTS: Out of the 124 participants that met the criteria for inclusion, 21 were diagnosed with DS and 103 with non-DS-related IDD. Twenty out of 21 participants with DS were successfully matched. Clinically significant weight loss was seen at 18 months in participants with DS (-5.2%) and non-DS-related IDD (-6.8%), with no difference between groups (P = 0.53). Significant reductions in energy intake were seen across the 18-month intervention in both DS and non-DS-related IDD groups with between-group differences at 12 months only (1119 vs. 1492 kcal/day, respectively; P = 0.003). Although MVPA did not increase in either group across the intervention, those with non-DS-related IDD had higher levels of MVPA compared with those with DS across 18 months. CONCLUSION: Participants with DS lost a clinically significant amount of weight across the 18-month intervention. Compared with those with non-DS-related IDD, those with DS lost similar amounts of weight, had similar decreases in energy intake and participated in less MVPA across the 18-month intervention. Although individuals with DS have physiological factors that may contribute to obesity, weight management interventions designed for individuals with IDD may be equally effective in this population.

Dominant and sensitive control of oxidative flux by the ATP-ADP carrier in human skeletal muscle mitochondria: Effect of lysine acetylation.

The adenine nucleotide translocase (ANT) of the mitochondrial inner membrane exchanges ADP for ATP. Mitochondria were isolated from human vastus lateralis muscle (n = 9). Carboxyatractyloside titration of O2 consumption rate (Jo) at clamped [ADP] of 21 µM gave ANT abundance of 0.97 ±â€¯0.14 nmol ANT/mg and a flux control coefficient of 82% ±â€¯6%. Flux control fell to 1% ±â€¯1% at saturating (2 mM) [ADP]. The KmADP for Jo was 32.4 ±â€¯1.8 µM. In terms of the free (-3) ADP anion this KmADP was 12.0 ±â€¯0.7 µM. A novel luciferase-based assay for ATP production gave KmADP of 13.1 ±â€¯1.9 µM in the absence of ATP competition. The free anion KmADP in this case was 2.0 ±â€¯0.3 µM. Targeted proteomic analyses showed significant acetylation of ANT Lysine23 and that ANT1 was the most abundant isoform. Acetylation of Lysine23 correlated positively with KmADP, r = 0.74, P = 0.022. The findings underscore the central role played by ANT in the control of oxidative phosphorylation, particularly at the energy phosphate levels associated with low ATP demand. As predicted by molecular dynamic modeling, ANT Lysine23 acetylation decreased the apparent affinity of ADP for ANT binding.

The feasibility of using pedometers for self-report of steps and accelerometers for measuring physical activity in adults with intellectual and developmental disabilities across an 18-month intervention.

BACKGROUND: Improving physical activity in adults with intellectual and developmental disabilities (IDDs) is recommended to improve weight loss and general health. However, in order to determine the success of physical activity interventions, identification of feasible methods for assessment of physical activities is necessary. The purpose of this study is to assess the feasibility of adults with IDD to track daily steps and wear an accelerometer. METHODS: Overweight/obese adults with mild to moderate IDD followed a diet and physical activity program for 18 months. All participants were asked to wear a pedometer and track steps daily by using a pedometer and to provide accelerometer data for 7 days at baseline, 6, 12 and 18 months. Adherence to the pedometer protocol and plausibility of the number of recorded steps were assessed, and these measures along with average wear time of the accelerometer were recorded. RESULTS: Data were collected from 149 participants (36.5 ± 12.2 years of age, 57% female). Participants recorded a step value on 81.5% of days across the 18-month study, with 40.9% of written days classified as plausible. When wearing the accelerometer, 26.8% of participants met the recommended 4-day/10-h wear time criterion at baseline, and 22.6, 24.8 and 18.8% met the criterion at 6, 12 and 18 months, respectively. CONCLUSIONS: Adults with IDD will adhere reasonably well to wearing a pedometer long term, but may be unable to record the step data accurately. Furthermore, adults with IDD have poor compliance with accelerometer protocols, and future studies should determine if a shorter wear time protocol would produce valid data in this population.

Portion-controlled meals provide increases in diet quality during weight loss and maintenance.

BACKGROUND: Behavioural weight-loss interventions utilising portion-controlled meals (PCMs) produce significant decreases in weight. However, their impact on diet quality during weight maintenance is unknown. The present study aimed to assess the influence of a weight management intervention employing PCMs and increased physical activity on diet quality during weight loss and weight maintenance. METHODS: One hundred and ninety-seven overweight and obese adults [67% women; mean (SD) BMI = 34.0 (4.6) kg m(-2); age = 46.1 (8.9) years] completed an 18-month trial. The weight-loss phase (0-6 months) consisted of energy restriction, which was achieved using PCMs plus fruits and vegetables and increased physical activity. During weight maintenance (6-18 months), participants consumed a diet designed to maintain weight loss. Body weight and dietary intake were assessed at baseline, and at 6, 12 and 18 months. The Healthy Eating Index-2010 (HEI) was calculated using data obtained from 3-day food records. RESULTS: Mean (SD) body weight was 14.3% (6.6%) and 8.7% (8.0%) below baseline at 6 and 18 months, respectively. The mean (SD) HEI-2010 score after weight loss [66.6 (9.4)] was significantly higher than baseline [46.4 (8.9)] and remained significantly higher than baseline at 18 months [57.7 (10.6)] (both P < 0.001). CONCLUSIONS: A weight management intervention using PCMs resulted in both clinically significant weight loss and increased diet quality scores, demonstrating that the use of PCMs during weight loss allows for meaningful changes in diet quality during weight maintenance.

Effects of prolonged war and repression on a country's health status and medical services: some evidence from Iran 1979-90.

The decade following the Islamic revolution in Iran is surveyed from the point of view of the various ways in which the repressive policies of the new regime and, from September 1980, the war with Iraq affected health professionals, medical education and publishing, health services and living conditions. Sources consulted include publications from inside and outside the country, by apologists for and opponents of the regime, and a variety of commentators. Topics studied in more detail are the campaign against drug abuse, the cultural revolution in the universities, the country's leading English-language medical journal, wartime conditions, and the society in the aftermath of the conflict. As well as predating and outlasting the war, the unfavourable climate of repression is seen to have exacerbated its effects in many ways. The population has displayed considerable resilience in the face of overwhelming odds, but the overall picture cannot give much grounds for optimism with regard to either their physical or mental well-being in the future. Particular cause for concern is the profound damage and prolonged neglect sustained by the most basic preconditions for health and medical care.

Vasoactive intestinal polypeptide (VIP) as a putative neurotransmitter in penile erection.

The localization of vasoactive intestinal polypeptide (VIP) in the male genitourinary tract was investigated in the rabbit and man by means of radioimmunoassay and immunohistochemistry. In addition, the in vitro effect of VIP upon penile smooth muscle from man, the Vervet monkey, and the rabbit was investigated. Significant concentrations of VIP immunoreactivity were found in the human penis and all the organs of the rabbit genital tract apart from the testis. VIP immunoreactive nerve fibres were observed in the erectile tissue of the human and rabbit penis and in the other organs of the rabbit genital tract apart from the testis. Fibres were most abundant in association with blood vessels, in smooth muscle tissue, and subepithelially in glandular tissue. Strips of smooth muscle taken from the corpus cavernosum of Vervet monkey and man showed a dose-dependent relaxation in response to VIP at concentrations of 6 X 10(-8) mol X L-1 and 6 X 10(-7) mol X L-1. The data indicate that VIP may be an inhibitory neurotransmitter involved in the nervous control of penile erection.

New theory on the mechanism of erection involving hitherto undescribed vessels.

47 cadaver penises were investigated by means of plastic, corrosion casts, direct dissection under a stereomicroscope, tissue clearing, and light microscopy. "Shunt" arteries connecting the deep arteries in the corpora cavernosa with vessels in the corpus spongiosum were found. When the penis is flaccid these arteries probably allow blood to pass through the corpora cavernosa directly into the veins of the corpus spongiosum. Constriction of the shunt arteries may divert blood through the helicine arteries into the spaces of the corpora cavernosa, thus producing tumescence and erection. 20 of the cadaver penises had no direct vascular connection between the corpora cavernosa and the corpus spongiosum or glans. This supports the hypothesis that such fistulae, which have been reported in impotent patients are pathological structures.