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BackgroundWrist-worn activity trackers are popular, and an increasing number of these devices are equipped with heart rate (HR) measurement capabilities. However, the validity of HR data obtained from such trackers has not been thoroughly assessed outside the laboratory setting. ObjectiveThis study aimed to investigate the validity of HR measures of a high-cost consumer-based tracker (Polar A370) and a low-cost tracker (Tempo HR) in the laboratory and free-living settings. MethodsParticipants underwent a laboratory-based cycling protocol while wearing the two trackers and the chest-strapped Polar H10, which acted as criterion. Participants also wore the devices throughout the waking hours of the following day during which they were required to conduct at least one 10-min bout of moderate-to-vigorous physical activity (MVPA) to ensure variability in the HR signal. We extracted 10-second values from all devices and time-matched HR data from the trackers with those from the Polar H10. We calculated intraclass correlation coefficients (ICCs), mean absolute errors, and mean absolute percentage errors (MAPEs) between the criterion and the trackers. We constructed decile plots that compared HR data from Tempo HR and Polar A370 with criterion measures across intensity deciles. We investigated how many HR data points within the MVPA zone (≥64% of maximum HR) were detected by the trackers. ResultsOf the 57 people screened, 55 joined the study (mean age 30.5 [SD 9.8] years). Tempo HR showed moderate agreement and large errors (laboratory: ICC 0.51 and MAPE 13.00%; free-living: ICC 0.71 and MAPE 10.20%). Polar A370 showed moderate-to-strong agreement and small errors (laboratory: ICC 0.73 and MAPE 6.40%; free-living: ICC 0.83 and MAPE 7.10%). Decile plots indicated increasing differences between Tempo HR and the criterion as HRs increased. Such trend was less pronounced when considering the Polar A370 HR data. Tempo HR identified 62.13% (1872/3013) and 54.27% (5717/10,535) of all MVPA time points in the laboratory phase and free-living phase, respectively. Polar A370 detected 81.09% (2273/2803) and 83.55% (9323/11,158) of all MVPA time points in the laboratory phase and free-living phase, respectively. ConclusionsHR data from the examined wrist-worn trackers were reasonably accurate in both the settings, with the Polar A370 showing stronger agreement with the Polar H10 and smaller errors. Inaccuracies increased with increasing HRs; this was pronounced for Tempo HR.

Reading and writing skills are intricately associated, and their mutual influence is seen as a dynamic process during literacy development for English. However, a broader understanding of the cross-domain development of literacy would be gained by examining literacy acquisition across different languages and scripts. An advantageous approach is to examine multiple language learning in a within-person design by investigating bilinguals during the earliest phases of literacy development. In this study, we contrast bilingual children who are learning English plus an Asian script (Chinese, Malay, or Tamil) to shed some light on language-general and -specific aspects of the interrelations of literacy skills. In a longitudinal design using cross-lag analysis, 620 bilingual children were administered reading and writing (spelling) tasks for English and their other script across 3 years (kindergarten into primary school entry). Models of English reading and writing were different for the three bilingual groups: Chinese and Tamil speakers showed relational patterns similar to monolingual results, but Malay speakers showed only a later reading-to-spelling influence. Models of cross-domain relations within each additional language also revealed differences across groups, suggesting language specific aspects of literacy development. Malay, a transparent orthography, supported bi-directional influence across skills consistently, while Chinese showed only an initial bidirectional influence, and Tamil supported a later spelling-to reading influence. Finally, cross-language influences differed between bilingual groups for each skill: with a consistent mutual influence for Malay-English reading, and a mutual influence for early Chinese-English spelling and later Malay-English spelling. Findings suggest that new perspectives of cross-linguistic models of literacy development are in order.

An awareness of a patient's risk profile for glaucoma and the importance of early detection can help prevent vision loss that is irreversible once it occurs. Knowledge of the algorithms guiding glaucoma treatment options, the medications used and factors leading to nonadherence, as well as the increasing interest in laser therapy and lifestyle and nutrition interventions, can further aid disease management. [ABSTRACT FROM AUTHOR]

Purpose To use optical coherence tomography angiography (OCTA) parameters from both the retinal and choroidal microvasculature to detect the presence and severity of diabetic retinopathy (DR).Method This is a cross-sectional case–control study. OCTA parameters from retinal vasculature, fovea avascular zone (FAZ) and choriocapillaris were evaluated from 3×3 mm² fovea-centred scans. Areas under the receiver operating characteristic (ROC) curve were used to compare the discriminative power on the presence of diabetes mellitus (DM), the presence of DR and need for referral: group 1 (no DM vs DM no DR), group 2 (no DR vs any DR) and group 3 (non-proliferative DR (NPDR) vs proliferative DR (PDR)).Results 35 eyes from 27 participants with no DM and 132 eyes from 75 with DM were included. DR severity was classified into three groups: no DR group (62 eyes), NPDR (51 eyes), PDR (19 eyes). All retinal vascular parameters, FAZ parameters and choriocapillaris parameters were strongly altered with DR stages (p<0.01), except for the deep plexus FAZ area (p=0.619). Choriocapillaris parameters allowed to better discriminate between no DM versus DM no DR group compared with retinal parameters (areas under the ROC curve=0.954 vs 0.821, p=0.006). A classification model including retinal and choroidal microvasculature significantly improved the discrimination between DR and no DR compared with each parameter separately (p=0.029).Conclusions Evaluating OCTA parameters from both the retinal and choroidal microvasculature in 3×3 mm scans improves the discrimination of DM and early DR. [ABSTRACT FROM AUTHOR]

Background: There remains uncertainty regarding optimal definitive management for malignant posterior circulation infarcts (MPCI). While guidelines recommend neurosurgery for malignant cerebellar infarcts that are refractory to medical therapy, concerns exist about the functional outcome and quality of life after decompressive surgery. Objective: This study aims to evaluate the outcomes of surgical intervention compared to medical therapy in MPCI. Methods: In this systematic review, MEDLINE, Embase and Cochrane databases were searched from inception until 2 April 2021. Studies were included if they involved posterior circulation strokes treated with neurosurgical intervention and reported mortality and functional outcome data. Data were collected according to PRISMA guidelines. Results: The search yielded 6677 studies, of which 31 studies (comprising 723 patients) were included for analysis. From the included studies, we found that surgical therapy led to significant differences in mortality and functional outcomes in patients with severe disease. Neurological decline and radiological criteria were often used to decide the timing for surgical intervention, as there is currently limited evidence for preventative neurosurgery. There is also limited evidence for the superiority of one surgical modality over another. Conclusion: For patients with MPCI who are clinically stable at the time of presentation, in terms of mortality and functional outcome, surgical therapy appears to be equivocal to medical therapy. Reliable evidence is lacking, and further prospective studies are rendered. [ABSTRACT FROM AUTHOR]

Not unlike mainstream society of the United States, Indian Country faces new challenges regarding the values, mores, and behavior of its young people. Since their first encounters with European explorers, American Indians have fought to preserve their culture and traditions. Federal policies that addressed the "Indian problem" by establishing reservations and BIA boarding schools, as well as through the implementation of assimilation, termination, and relocation programs, are but a few illustrations of a long history of institutional efforts to colonize American Indian culture and identity. Centuries of these violent efforts have slowly eroded the foundations of Native traditions and have manifested themselves in the drug and alcohol abuse, social isolation, family violence, and negative economic opportunity that plague many American Indian communities. In this context, Indian Country is fertile ground for the proliferation of youth gangs, for many young Indians have come to believe that traditional values are irrelevant to their lives. In this article, the author discusses the circumstances that can lead to the proliferation of youth gangs, the characteristics of gangs, and methods that can be used to prevent or curtail youth involvement in gangs. A case study of gang development in Los Angeles is also presented. (Contains 19 endnotes.)

Physical inactivity is a global public health challenge, and effective, large-scale interventions are needed. We examined the effectiveness of a population-wide mobile health (mHealth) intervention in Singapore, National Steps Challenge Season 3 (NSC3) and 2 booster challenges (Personal Pledge and Corporate Challenge). The study includes 411,528 participants. We used regression discontinuity design and difference-in-difference with fixed-effects regression to examine the association of NSC3 and the additional booster challenges on daily step counts. Participants tended to be female (58.5%), with an average age of 41.5 years (standard deviation, 13.9) and body mass index (weight (kg)/height (m)2) of 23.8 (standard deviation, 4.5). We observed that NSC3 was associated with a mean increase of 1,437 steps (95% confidence interval (CI): 1,408, 1,467) per day. Enrollments in Personal Pledge and Corporate Challenge were associated with additional mean increases of 1,172 (95% CI: 1,123, 1,222) and 896 (95% CI: 862, 930) steps per day, respectively. For NSC3, the associated mean increase in the step counts across different sex and age groups varied, with greater increases for female participants and those in the oldest age group. We provide real-world evidence suggesting that NSC3 was associated with improvements in participants' step counts. Results suggest NSC3 is an effective and appealing population-wide mHealth physical activity intervention. [ABSTRACT FROM AUTHOR]