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101.
《Health & place》2019
Activity spaces are increasingly used to understand how people interact with their environment and engage in activity but their use may raise challenges regarding causal inference. We conducted a systematic review of findings and the methodological, analytical and conceptual issues relevant to causal inference. Studies were included if they comprised a spatial summary of locations visited, assessed any part of the causal pathway between the environment, physical activity and health, and used quantitative or qualitative methods. We searched seven electronic databases in January 2018 and screened 11910 articles for eligibility. Forty-seven studies were included for review. Studies answered research questions about features of or environmental features within activity spaces using a range of spatial and temporal summary techniques. The conceptual challenge of using activity spaces to strengthen causal inference was rarely considered, although some studies discussed circularity, temporality, and plausibility. Future studies should use longitudinal and experimental designs and consider the potential and actual use of spaces for physical activity, and their relationship with total levels of activity. 相似文献
102.
Luke Volgin 《The Australian journal of forensic sciences》2019,51(4):S10-S13
ABSTRACTThe advancement of DNA technology comes with the increased sensitivity of amplification systems, where DNA traces are routinely detected without a known biological source. These systems also have increased discriminating capacity, providing larger likelihood ratios (LRs) when a corresponding DNA profile is observed. Questions in court are shifting from identity to transfer mechanism, where the presence of an individual’s DNA is conceded by both parties, but the activities that led to its deposition is in dispute. One way of handling propositions developed at the activity level is with the use of graphical structures known as Bayesian Networks (BNs). The following is an evaluation of a case, given activity level propositions, through the application of BNs. Alternative case findings will be explored for the given scenario to show the potential value of the DNA evidence for different outcomes within the broader case context. 相似文献
103.
《Archives of physical medicine and rehabilitation》2019,100(10):1924-1931
ObjectiveValidation of linking coefficients to transform Pediatric Spinal Cord Injury Activity Measure (PEDI-SCI/AM) scores to adult Spinal Cord Injury-Functional Index (SCI-FI) scores.DesignThis cross-sectional study administered PEDI-SCI/AM and SCI-FI computerized adaptive tests (CATs) and short forms (SFs) to children with SCI and parents or caregivers.SettingHospitals, university, and rehabilitation institute.ParticipantsAbout 107 children with SCI and 96 parent or caregivers.InterventionsNot applicable.Main Outcome MeasuresLinking coefficients estimated SCI-FI (est-SCI-FI) scores from PEDI-SCI/AM scores for matched domains. Correlations between est-SCI-FI and actual SCI-FI scores were calculated. If correlations exceeded the criterion linking (0.866), the following analyses to compare est-SCI-FI and actual SCI-FI scores were conducted: paired t tests, intraclass correlation coefficients (ICCs 3, 1), percent of cases with absolute score differences at different thresholds.ResultsTwo matched domains, PEDI-SCI/AM Daily Routine/SCI-FI Self-Care and PEDI-SCI/AM General Mobility/SCI-FI Basic Mobility, met the linking criterion for both respondent-types (parent and child) and administration modes (CAT and SF). PEDI-SCI/AM Daily Routine and SCI-FI Fine Motor Function did not meet linking criterion for respondent type or mode. The linking criterion was met for wheelchair domains (child SF and CAT) and ambulation domains (child SF only). Significant differences between est-SCI-FI and actual SCI-FI scores were noted for all matched domains except Daily Routine/Self-Care (child SF only; parent SF and CAT). ICC values showed excellent agreement (range=0.75-0.89). Absolute differences between est-SCI-FI and actual SCI-FI scores were less than 1 standard deviation (except wheelchair CAT child).ConclusionsLinking coefficients applied to PEDI-SCI/AM scores can provide valid SCI-FI estimates that vary by domain, mode, and respondent type. 相似文献
104.
Senescence plays an important role in neurodegenerative diseases and involves key molecular changes induced by several mechanisms such as oxidative stress, telomere shortening and DNA damage. Potential therapeutic strategies directed to counteract these molecular changes are of great interest for the prevention of the neurodegenerative process. Telomerase is a ribonucleoprotein composed of a catalytic subunit (TERT) and a RNA subunit (TERC). It is known that the telomerase is involved in the maintenance of telomere length and is a highly expressed protein in embryonic stages and decreases in adult cells. In the last decade, a growing number of studies have shown that TERT has neuroprotective effects in cellular and animal models after a brain injury. Significantly, differences in TERT expression between controls and patients with major depressive disorder have been observed. More recently, TERT has been associated with the decrease in reactive oxygen species and DNA protection in mitochondria of neurons. In this review, we highlight the role of TERT in some neurodegenerative disorders and discuss some studies focusing on this protein as a potential target for neuroprotective therapies. 相似文献
105.
《Sleep medicine》2021
ObjectiveThe purposes of the present study were to explore independent and interactive associations between night sleep duration, night sleep quality and coronary heart disease (CHD) based on a rural population in China.MethodsA total of 27,935 participants (11,177 men and 16,758 women) were investigated from the Henan Rural Cohort. Information about sleep was assessed by using the Pittsburgh Sleep Quality Index (PSQI). Restricted cubic splines and logistic regression were used to estimate the relationship between night sleep duration and quality with CHD.ResultAmong the 27,935 participants, 1506 participants with CHD were identified. Compared with participants with scores lower than 3, the odds ratios (ORs) and 95% confidence intervals (95% CIs) of participants with score of 3–5, 6–8, ≥9 were respectively 1.42 (1.24–1.63), 1.99 (1.70–2.33), and 2.56 (2.13–3.08) with full adjustment of covariates. Compared with night sleep duration of 7 h, men and women who slept less than 5 h were 1.55 (1.11–2.17), 1.12 (0.59–2.12) and 1.80 (1.20–2.68), after being adjusted ORs (95% CIs) of the total. Moreover, the ORs and 95% CIs of CHD increased with the shortening of sleep duration at PSQI score above the highlighted levels.ConclusionPoor sleep quality and short night sleep duration were all associated with CHD in Chinese rural areas. Moreover, the association was more obvious in women. In addition, the strongest prevalence of CHD was found in short sleepers with poor sleep quality. 相似文献
106.
《Health & place》2022
This study aimed to understand the perceived effects of the COVID-19 pandemic on physical activity, recreation walking, and use of recreational facilities; and if the COVID-19 pandemic amplified disparities in physical activity, recreational walking, and use of recreational facilities related to the levels of neighborhood disadvantage. Recreational walking and the use of neighborhood streets and green spaces significantly decreased in high deprivation areas but not in low deprivation areas during the pandemic. While COVID-19 has negatively affected overall recreational activities, the inequitable impact on recreational walking and use of outdoor recreational facilities has been more evident in disadvantaged neighborhoods with greater deprivation. 相似文献
107.
《Zeitschrift für medizinische Physik》2021,31(4):378-387
PurposeSelective internal radiation therapy (SIRT) is a treatment for various kinds of liver tumours by injecting 90Y bearing microspheres into the liver vessels. To perform meaningful post-treatment dosimetry, quantitative imaging is performed.MethodsThis work uses a Monte-Carlo based reconstruction software with scatter and attenuation correction and collimator modelling that allows the quantification of 90Y bremsstrahlung SPECT/CT data. A dataset comprising 17 patients and measurements on a Jaszczak phantom, a NEMA IEC Body phantom and an anthropomorphic liver phantom are analysed and activities and dose values are acquired. These measured values are compared with applied activities and pre-treatment calculations, allowing to assess the quality of the SPECT reconstruction. A detailed uncertainty budget is presented, including uncertainties of the dose calibrator, the count rate, non-included interactions and other factors.ResultsThe applied method is validated by finding measurements repeatable within the given uncertainty, and it is shown the influence of various parameters on the reconstruction process is negligible. Furthermore, activities and doses measured in the phantoms show good agreement with calculated values, if they are corrected for partial volume effects.ConclusionsThe strict observation of metrological requirements and the creation of an uncertainty budget increase the reliability and traceability of this novel approach to 90Y dosimetry. It gives an example of successful voxel-based dosimetry based on quantitative 90Y SPECT/CT image data. 相似文献
108.
109.
110.
《亚太生殖杂志》2014,3(1):1-7
ObjectiveTo investigate the telomere length in bovine offspring produced by a cloned and control bull, and the telomerase activity in embryos produced with the same technology.MethodsFive daughters of a control and five daughters of a bull cloned using a fibroblast of the control were produced by IVF using sperm of the two bulls. Blood samples of the offspring were collected at 2, 6, and 12 months of age and the relative telomere length (RTL) was assessed by flow cytometry. At same time the body growth, hematological profile, and clinical biochemistry of the same progeny was extensively surveyed, and results have been reported in a previous work. Thereafter, the telomerase activity was assessed using a real time PCR quantitative assay in groups of embryos produced with the same technology.ResultsThe offspring of the clone exhibited a modest, but significant (P<0.05), shortening of the telomeres (21.36%, 20.56% and 20.56%) compared to that of the control (23.78%, 23.53% and 22.43%) as mean values determined at 2, 6 and 12 months, respectively. Shortening of telomeres in respect to the age was not significant. No statistical difference was reported between telomerase activity assessed in 144 cloned (3.4−03 ± 2.4−03 amoles/μL) and 80 control (2.1−03 ± 1.8−03 amoles/μL) embryos.ConclusionsThe results have revealed a moderate shortening of telomeres in the offspring of the clone with respect to control. However, this study did not evidence differences in the two progenies that suggest welfare problems during the first year of life. 相似文献