670 research outputs found
Rapid, Responsive, and Relevant? A Systematic Review of Rapid Evaluations in Health Care
Changing health-care climates mean evaluators need to provide findings within shorter time frames, but challenges remain in the creation of rapid research designs capable of delivering quality data to inform decision-making processes. We conducted a review of articles to grapple with these challenges and explore the ways in which rapid evaluations have been used in health care. We found different labels being used to define rapid evaluations and identified a trend in the design of evaluations, where evaluators are moving away from short studies to longer evaluations with multiple feedback loops or cyclical stages. Evaluators are using strategies to speed up evaluations: conducting data collection and analysis in parallel, eliminating the use of transcripts, and utilizing larger evaluation teams to share the workload. Questions persist in relation to the suitability of rapid evaluation designs, the trustworthiness of the data, and the degree to which evaluation findings are used to make changes in practice
Effects of Core-valence and Core-core Correlation On the Line-strength of the Resonance Lines In Li-i and Na-i
The resonance lines in Li I and Na I both exhibit a puzzling discrepancy between experiment and accurate ab initio calculations. Only results from a semiempirical method, that in principal neglects core-core correlation, agree with the experiments. The agreement with a multiconfiguration Hartree-Fock calculation, including only core-valence correlation, shows that this might be fortuitous. A method for including some core-core correlation is designed and gives results in excellent agreement with other accurate ab initio methods
Progress in Agricultural Research at the North Central Substation
Thousands of acres of farm land in the north central part of South Dakota have their productive future tied up with the 240 acres used for experimental research at the Substation at Eureka. Established nearly 50 years ago by the state legislature, which set aside state school lands for agricultural research, the North Central Substation is the proving ground for new agricultural methods and a living record of the accumulative effects of the old. As early as 1908, rotation experiments were started which became the first historical record in the northern plains area of the effects of cropping practices on the soil. At that time, the entire surrounding country was in wheat. There were no crop rotations, since the organic matter of the soil was good and the fertility level high. Also, there was no weed problem then. Later, the Experiment Station was to be accused of scattering weeds in one of the most interesting stories to be uncovered in the development of experimental research in this area. Foreseeing the time when the fertility of the land might become dangerously lowered by the practice of continuous cropping which was being carried on at that time, the Substation set up experimental plots. These included the basic crops of rotation-cultivated crops, small grain and legumes. In this case, the legume was sweet clover. (See more in Text
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Feasibility of incorporating objective measures of physical activity in the STEPS program. A pilot study in Malawi
Background
Physical activity is an important determinant of human health but it is inherently difficult to measure. Global surveillance systems for physical activity have so far only included self-report measures, which capture only a small subset of daily activity and are limited due to issues of recall bias. Wrist-worn accelerometry offers a reasonably cost-effective objective method of measuring physical activity during free-living with proven feasibility in large-scale population studies.
The key objective of this project was to pilot wrist-worn accelerometry within a surveillance setting in order to inform the implementation of this methodology into the global WHO STEPS programme.
Method development and implementation
Accelerometry protocols were developed and deployed within an existing STEPS survey in two regions of Malawi (Dowa and Lilongwe). This also included developing training for local staff. Survey information was collected on tablets. Accelerometers could only be set up on PCs, so the protocol was adapted to do this in advance of recruiting participants. For this, an alternative Participant ID linkage system was developed to enable linking accelerometer files to the rest of the survey data.
On the whole, the implementation was successful. During the process evaluation, some issues were identified. For example, black wrist straps were culturally associated with the Devil by some participants. A total of 499 participants were recruited for Step 1 and 2, of whom 446 returned for Step 3 measurements which included accelerometry.
The accelerometry data collection was well accepted by both fieldwork team members and study participants, with only four participants (<1% of those eligible) declining to wear the device. There were no major technical issues with devices, although a small number of wrist straps were damaged and 13 monitors were lost (3% of deployed). Of 456 accelerometer files retrieved, 410 files (90%) could be linked to survey participants.
All but two accelerometer files could be processed with standard techniques to produce participant-level summary results. Sufficient valid data (defined as at least 48 hours of monitor wear time with reasonable diurnal representation) were available for 386 survey participants (87% of eligible).
Results
Objective levels of physical activity in Malawi from this pilot study were about 50% higher than levels observed in the UK using similar methodology. Rural dwellers were more active than urban dwellers, particularly in the morning hours of the day. Men had higher activity levels compared to women, and there were decreasing trends with advancing age.
Conclusion and recommendations
This pilot demonstrated that it is feasible to implement wrist-worn accelerometry within the STEPS program in settings such as Malawi. Detailed description of objectively measured physical activity patterns could be produced from nearly all accelerometer files retrieved, including behavioural indicators known to be important for human health.
In future surveys, culturally specific issues that could impact data collection should be identified early in the fieldwork planning stage and changes to the protocol made. Experiences from this pilot have led to development of software platforms that allow accelerometers to be set up from Android tablets at the point of issuing the device to the participant, which would simplify future fieldwork training and reduce risk of data linkage error
SelfHAR: Improving Human Activity Recognition through Self-training with Unlabeled Data
Machine learning and deep learning have shown great promise in mobile sensing
applications, including Human Activity Recognition. However, the performance of
such models in real-world settings largely depends on the availability of large
datasets that captures diverse behaviors. Recently, studies in computer vision
and natural language processing have shown that leveraging massive amounts of
unlabeled data enables performance on par with state-of-the-art supervised
models.
In this work, we present SelfHAR, a semi-supervised model that effectively
learns to leverage unlabeled mobile sensing datasets to complement small
labeled datasets. Our approach combines teacher-student self-training, which
distills the knowledge of unlabeled and labeled datasets while allowing for
data augmentation, and multi-task self-supervision, which learns robust
signal-level representations by predicting distorted versions of the input.
We evaluated SelfHAR on various HAR datasets and showed state-of-the-art
performance over supervised and previous semi-supervised approaches, with up to
12% increase in F1 score using the same number of model parameters at
inference. Furthermore, SelfHAR is data-efficient, reaching similar performance
using up to 10 times less labeled data compared to supervised approaches. Our
work not only achieves state-of-the-art performance in a diverse set of HAR
datasets, but also sheds light on how pre-training tasks may affect downstream
performance
Levels of domain-specific physical activity at work, in the household, for travel and for leisure among 327 789 adults from 104 countries
Objective: To compare the country-level absolute and relative contributions of physical activity at work and in the household, for travel, and during leisure-time to total moderate-to-vigorous physical activity (MVPA). Methods: We used data collected between 2002 and 2019 from 327 789 participants across 104 countries and territories (n=24 low, n=34 lower-middle, n=30 upper-middle, n=16 high-income) from all six World Health Organization (WHO) regions. We calculated mean min/week of work/household, travel and leisure MVPA and compared their relative contributions to total MVPA using Global Physical Activity Questionnaire data. We compared patterns by country, sex and age group (25–44 and 45–64 years). Results: Mean MVPA in work/household, travel and leisure domains across the 104 countries was 950 (IQR 618–1198), 327 (190–405) and 104 (51–131) min/week, respectively. Corresponding relative contributions to total MVPA were 52% (IQR 44%–63%), 36% (25%–45%) and 12% (4%–15%), respectively. Work/household was the highest contributor in 80 countries; travel in 23; leisure in just one. In both absolute and relative terms, low-income countries tended to show higher work/household (1233 min/week, 57%) and lower leisure MVPA levels (72 min/week, 4%). Travel MVPA duration was higher in low-income countries but there was no obvious pattern in the relative contributions. Women tended to have relatively less work/household and more travel MVPA; age groups were generally similar. Conclusion: In the largest domain-specific physical activity study to date, we found considerable country-level variation in how MVPA is accumulated. Such information is essential to inform national and global policy and future investments to provide opportunities to be active, accounting for country context
Prospective Associations of Accelerometer-Measured Physical Activity and Sedentary Time With Incident Cardiovascular Disease, Cancer, and All-Cause Mortality.
Insufficient moderate-to-vigorous-intensity physical activity (MVPA) and high volumes of sedentary time (ST) have both been associated with increased risk of all-cause mortality, cardiovascular disease (CVD), and some cancers1. However, epidemiological evidence has mostly relied on self-reported physical activity (PA) measures, which are prone to reporting bias and measurement error. Cohort studies incorporating objective assessments of PA are emerging2-4; but few investigate relationships of accelerometer-measured PA and ST with clinical endpoints, particularly incident CVD, and include both men and women5. Additionally, the relevance of light-intensity physical activity (LIPA) in this context, which is an important contributor to total physical activity and may be a more feasible target for middle-to-older aged adults, remains unclear. Here, we examine the prospective associations of accelerometer-measured PA and ST with incident CVD (primary outcome), incident cancer, and all-cause mortality.The EPIC-Norfolk study (DOI 10.22025/2019.10.105.00004) has received funding from the Medical Research Council (MR/N003284/1 and MC-UU_12015/1) and Cancer Research UK (C864/A14136). PCD is supported by a National Health and Medical Research Council of Australia research fellowship (#1142685). PCD, TS, SB, KW and NJW are supported by the UK Medical Research Council [grant numbers MC_UU_12015/1 and MC_UU_12015/3]
Lifetime measurement of the metastable 3d 2D5/2 state in the 40Ca+ ion using the shelving technique on a few-ion string
We present a measurement of the lifetime of the metastable 3d 2D5/2 state in
the 40Ca+ ion, using the so-called shelving technique on a string of five
Doppler laser-cooled ions in a linear Paul trap. A detailed account of the data
analysis is given, and systematic effects due to unwanted excitation processes
and collisions with background gas atoms are discussed and estimated. From a
total of 6805 shelving events, we obtain a lifetime
tau=1149+/-14(stat.)+/-4(sys.)ms, a result which is in agreement with the most
recent measurements.Comment: 10 pages, 7 figures. Submitted for publicatio
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Socioeconomic position and sedentary behavior in Brazilian adolescents: A life-course approach.
Socioeconomic position (SEP) is a potential correlate of sedentary behavior in adolescents. The aim of this study was to examine the associations between SEP and self-reported and objective measures of sedentary behavior in adolescents, using a life-course approach. Data from the 1993 Pelotas (Brazil) Birth Cohort Study were analyzed (N=5249). Cross-sectional and longitudinal associations between multiple SEP indicators (maternal education, family income, SEP composite, cumulative family income) at birth, 11, 15 and 18years, and five sedentary behavior outcomes (≥4h/day screen time; ≥4h/day TV; ≥2h/day computer; ≥2h/day video game; ≥12.7h/day objectively measured sedentary time) at 11, 15 and 18years, were examined. In cross-sectional analyses, higher SEP was positively associated with more screen time at ages 11 and 15years. There was a consistent and positive association between higher SEP with time spent using a computer, and with sedentary time assessed through accelerometry. SEP at birth had a positive and direct effect on screen, computer and total sedentary time at 18years. Participants in the highest cumulative income group had higher odds of high sedentary behavior in screen (OR: 2.40; 95% CI: 1.50-3.54), computer (OR: 7.35; 95% CI: 4.19-12.89) and total sedentary time (OR: 5.40; 95% CI: 3.53-10.35), respectively, compared with their counterparts with lower cumulative income. Our findings showed that SEP is an early determinant of sedentary behavior in adolescents
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