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2022 ◽  
Vol 15 (1) ◽  
Author(s):  
Hyo Jeong Yoo ◽  
Hye Sun Park ◽  
Dong-Oh Lee ◽  
Seong Hyun Kim ◽  
Gil Young Park ◽  
...  

Abstract Background Multi-segment foot models (MFMs) for assessing three-dimensional segmental foot motions are calculated via various analytical methods. Although validation studies have already been conducted, we cannot compare their results because the experimental environments in previous studies were different from each other. This study aims to compare the kinematics, repeatability, and reproducibility of five MFMs in the same experimental conditions. Methods Eleven healthy males with a mean age of 26.5 years participated in this study. We created a merged 29-marker set including five MFMs: Oxford (OFM), modified Rizzoli (mRFM), DuPont (DFM), Milwaukee (MiFM), and modified Shriners Hospital for Children Greenville (mSHCG). Two operators applied the merged model to participants twice, and then we analysed two relative angles of three segments: shank-hindfoot (HF) and hindfoot-forefoot (FF). Coefficients of multiple correlation (CMC) and mean standard errors were used to assess repeatability and reproducibility, and statistical parametric mapping (SPM) of the t-value was employed to compare kinematics. Results HF varus/valgus of the MiFM and mSHCG models, which rotated the segment according to radiographic or goniometric measurements during the reference frame construction, were significantly more repeatable and reproducible, compared to other models. They showed significantly more dorsiflexed HF and plantarflexed FF due to their static offset angles. DFM and mSHCG showed a greater range of motion (ROM), and some models had significantly different FF points of peak angle. Conclusions Under the same conditions, rotating the segment according to the appropriate offset angle obtained from radiographic or goniometric measurement increased reliability, but all MFMs had clinically acceptable reliability compared to previous studies. Moreover, in some models, especially HF varus/valgus, there were differences in ROM and points of peak angle even with no statistical difference in SPM curves. Therefore, based on the results of this study, clinicians and researchers involved in the evaluation of foot and ankle dysfunction need an understanding of the specific features of each MFM to make accurate decisions.


Author(s):  
Fang Li ◽  
Chun-Hao Chang ◽  
Chia-An Ho ◽  
Cheng-You Wu ◽  
Hung-Chih Yeh ◽  
...  

The maximal oxygen uptake (VO2max) prediction models established by step tests are often used for evaluating cardiorespiratory fitness (CRF). However, it is unclear which type of stepping frequency sequence is more suitable for the public to assess the CRF. Therefore, the main purpose of this study was to test the effectiveness of two 3-min incremental step-in-place (3MISP) tests (i.e., 3MISP30s and 3MISP60s) with the same total number of steps but different step-frequency sequences in predicting VO2max. In this cross-sectional study, a total of 200 healthy adults in Taiwan completed 3MISP30s and 3MISP60s tests, as well as cardiopulmonary exercise testing. The 3MISP30s and 3MISP60s models were established through multiple stepwise regression analysis by gender, age, percent body fat, and 3MISP-heart rate. The statistical analysis included Pearson’s correlations, the standard errors of estimate, the predicted residual error sum of squares, and the Bland–Altman plot to compare the measured VO2max values and those estimated. The results of the study showed that the exercise intensity of the 3MISP30s test was higher than that of the 3MISP60s test (% heart rate reserve (HRR) during 3MISP30s vs. %HRR during 3MISP60s = 81.00% vs. 76.81%, p < 0.001). Both the 3MISP30s model and the 3MISP60s model explained 64.4% of VO2max, and the standard errors of the estimates were 4.2043 and 4.2090 mL·kg−1·min−1, respectively. The cross-validation results also indicated that the measured VO2max values and those predicted by the 3MISP30s and 3MISP60s models were highly correlated (3MISP30s model: r = 0.804, 3MISP60s model: r = 0.807, both p < 0.001). There was no significant difference between the measured VO2max values and those predicted by the 3MISP30s and 3MISP60s models in the testing group (p > 0.05). The results of the study showed that when the 3MISP60s test was used, the exercise intensity was significantly reduced, but the predictive effectiveness of VO2max did not change. We concluded that the 3MISP60s test was physiologically less stressful than the 3MISP30s test, and it could be a better choice for CRF evaluation.


Author(s):  
Alessandro Gasparini ◽  
Tim P. Morris ◽  
Michael J. Crowther

Simulation studies allow us to explore the properties of statistical methods.They provide a powerful tool with a multiplicity of aims; among others: evaluating and comparing new or existing statistical methods, assessing violations of modelling assumptions, helping with the understanding of statistical concepts, and supporting the design of clinical trials.The increased availability of powerful computational tools and usable software has contributed to the rise of simulation studies in the current literature.However, simulation studies involve increasingly complex designs, making it difficult to provide all relevant results clearly.Dissemination of results plays a focal role in simulation studies: it can drive applied analysts to use methods that have been shown to perform well in their settings, guide researchers to develop new methods in a promising direction, and provide insights into less established methods.It is crucial that we can digest relevant results of simulation studies.Therefore, we developed INTEREST: an INteractive Tool for Exploring REsults from Simulation sTudies.The tool has been developed using the Shiny framework in R and is available as a web app or as a standalone package.It requires uploading a tidy format dataset with the results of a simulation study in R, Stata, SAS, SPSS, or comma-separated format.A variety of performance measures are estimated automatically along with Monte Carlo standard errors; results and performance summaries are displayed both in tabular and graphical fashion, with a wide variety of available plots.Consequently, the reader can focus on simulation parameters and estimands of most interest.In conclusion, INTEREST can facilitate the investigation of results from simulation studies and supplement the reporting of results, allowing researchers to share detailed results from their simulations and readers to explore them freely.


Author(s):  
Gregory Poskrebyshev

The empirical linear scaling dependencies between the literature (rHo(Xn,TAB)) and the calculated (rHo((Xn)i,CALC)) values of atomization of 31 reference aromatic and related compounds (T=298.15K), as well as their standard errors ((SE4)i(4)i, Stand.Dev.), are determined for the different quantum mechanical (QMi) approaches. These dependencies are compared and used for the determination of the values of rHo((Xn)i,CORRE)±3(SE4)i of atomization reactions of considered not reference aromatic compounds, as well as for the determination of their values of fHo((Xn)i,CORRE)±3(SE4)i. The values of fHo((Xn)i,CORRE)MEAN±3SEYE (≥99.4% confidence interval), determined using the intersections of the 3(SE4)i intervals, are consistent with all QMi approaches and their literature values. The M06-2X/6-311++G(d,p), M08HX/6-311++G(d,p) and wB97XD/6-311++G(d,p) approaches are recommended for the achievement of accuracy (SEYE)≤3.8 kJ/mol of the calculated values of fHo((Xn)i,CORRE)MEAN. The effects of the number of O-H groups, size and multiplicity of compounds on values of error, also studied in this work, demonstrate the limitations of using of several scaled dependencies.


Author(s):  
Huiyan Zhang ◽  
Yong Yu ◽  
Dan Yan ◽  
Kai Tang ◽  
Rongchuan Qiao

Abstract With unique orbital and physical characteristics, Triton is a very important target since it may contain information of the origin and evolution of the solar system. Besides space explorations, ground-based observations over long time also play key role on research of Triton. High-precision positions of Triton obtained from ground telescopes are of great significance for studying its orbital evolution and inverting the physical properties of Neptune. As a long-term observational target, Triton has been observed by the 1.56 m telescope of Shanghai Astronomical Observatory since 1996. In this paper, based on our AAPPDI software and with Gaia DR2 as the reference catalogue, 604 positions of Triton during 2010-2014 are calculated, with standard errors of $19mas-88mas$. A comparison between our results and the ephemeris (DE431+nep096) is also given.


Author(s):  
Shiue-Wei Lai ◽  
Kun-Zhe Tsai ◽  
Shen-Huei Wang ◽  
Yu-Kai Lin ◽  
Yen-Po Lin ◽  
...  

Backgrounds: Severe microcytic anemia has been associated with BP changes. Aims and Objectives: Whether the erythrocyte indices are associated with long-term BPV is unknown. This study aimed to investigate the association of hemoglobin levels and erythrocyte size with long-term blood pressure variability (BPV) in young males. Methods: This study included 1,112 healthy military males, averaging 32 years of age, in Taiwan. All participants took a measurement of systolic and diastolic BP (SBP and DBP) every two-year from 2012 to 2018 (2012-14, 2014-15, 2015-16, 2016-18). Lev-els of hemoglobin and mean corpuscular volume (MCV) of erythrocytes were obtained at the first visit. Long-term BPV was assessed by the standard deviation (SD) and aver-age real variability (ARV). Multivariate linear regression analysis with adjustment for the baseline BP levels and other covariates was used to elucidate the association. Results: Hemoglobin levels were borderline positively correlated with SD DBP (β and standard errors = 0.016 (0.009), P =0.06). In those with hemoglobin levels of 10.0-13.9 g/dL, hemoglobin was negatively correlated with SDSBP (β= -0.039 (0.018), P =0.03). In contrast, MCV levels were borderline positively correlated with SDSBP (β =0.085 (0.052), P =0.09). In those with MCV levels <80 fL, MCV was positively correlated with SDSBP and ARVSBP (β= 0.445 (0.210) and 0.286 (0.149), p = 0.03 and 0.05, re-spectively). Conclusion: There were inconsistent patterns for the associations of erythrocyte indices with long-term BPV. We found a U-shaped relationship of hemoglobin levels with sys-tolic BPV, whereas there was a positive linear relationship of hemoglobin and MCV levels with diastolic BPV, respectively.


2021 ◽  
Vol 6 (12) ◽  
pp. 233-246
Author(s):  
James Cristofer Mendoza Hermoso ◽  
Jan Myles Madriaga Sadang ◽  
Nathan Carlo Blanco Evangelista ◽  
Marie Antoinette Lukban Rosete

In recent years, infrastructure investments in the Philippines have sharply increased; however, there has been a limited study about whether these have effectively improved productivity, specifically in the Philippines' services and wholesale/retail sectors. This paper examines the effects of investments in roads, bridges, and water supply systems on services and wholesale/retail productivity using the annual dataset from 15 regions in the Philippines from 2017 to 2019. The results of a panel-data analysis with Panel-Corrected Standard Errors (PCSE) show that investments in roads, bridges, and water supply systems positively influence productivity in services and wholesale/retail, with investment for the construction or rehabilitation of roads having the greatest impact.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0260571
Author(s):  
Carlos Pineda-Antunez ◽  
David Contreras-Loya ◽  
Alejandra Rodriguez-Atristain ◽  
Marjorie Opuni ◽  
Sergio Bautista-Arredondo

Background Identifying approaches to improve levels of health care provider knowledge in resource-poor settings is critical. We assessed level of provider knowledge for HIV testing and counseling (HTC), prevention of mother-to-child transmission (PMTCT), and voluntary medical male circumcision (VMMC). We also explored the association between HTC, PMTCT, and VMMC provider knowledge and provider and facility characteristics. Methods We used data collected in 2012 and 2013. Vignettes were administered to physicians, nurses, and counselors in facilities in Kenya (66), Rwanda (67), South Africa (57), and Zambia (58). The analytic sample consisted of providers of HTC (755), PMTCT (709), and VMMC (332). HTC, PMTCT, and VMMC provider knowledge scores were constructed using item response theory (IRT). We used GLM regressions to examine associations between provider knowledge and provider and facility characteristics focusing on average patient load, provider years in position, provider working in another facility, senior staff in facility, program age, proportion of intervention exclusive staff, person-days of training in facility, and management score. We estimated three models: Model 1 estimated standard errors without clustering, Model 2 estimated robust standard errors, and Model 3 estimated standard errors clustering by facility. Results The mean knowledge score was 36 for all three interventions. In Model 1, we found that provider knowledge scores were higher among providers in facilities with senior staff and among providers in facilities with higher proportions of intervention exclusive staff. We also found negative relationships between the outcome and provider years in position, average program age, provider working in another facility, person-days of training, and management score. In Model 3, only the coefficients for provider years in position, average program age, and management score remained statistically significant at conventional levels. Conclusions HTC, PMTCT, and VMMC provider knowledge was low in Kenya, Rwanda, South Africa, and Zambia. Our study suggests that unobservable organizational factors may facilitate communication, learning, and knowledge. On the one hand, our study shows that the presence of senior staff and staff dedication may enable knowledge acquisition. On the other hand, our study provides a note of caution on the potential knowledge depreciation correlated with the time staff spend in a position and program age.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Eva Norén Selinus ◽  
Natalie Durbeej ◽  
Yiqiang Zhan ◽  
Paul Lichtenstein ◽  
Sebastian Lundström ◽  
...  

Abstract Background Physical activity has been documented to influence several aspects of physical and mental health. Growing evidence shows that physical activity can improve attention. Less is known about how symptoms of inattention and hyperactivity / impulsivity in childhood are associated with physical activity in adolescence. We aimed to explore this relationship further. Methods We used a cohort of 3949 Swedish children (1884 boys and 2065 girls) with data collected at ages 9 (or 12) and 15. We investigated the influence of symptoms of inattention and hyperactivity / impulsivity in childhood – age 9/12 (inattention and hyperactivity/impulsivity separately) on self-rated physical activity at age 15, using multiple logistic regression models. We considered potential confounders such as sex, parental education level, physical activity in childhood and neurodevelopmental comorbidity. A cluster robust sandwich estimator was applied to adjust the standard errors for the nested twin data when computing the regression models. Results Symptoms of inattention in childhood (9/12) predicted less physical activity in adolescence (age 15) (OR = 0.83 CI = 0.78–0.89), whereas the opposite was true for hyperactivity/impulsivity (OR = 1.08 CI = 1.02–1.10). These associations still remained when taking possible confounders into account including neurodevelopmental and neurodevelopmental related comorbidity. Conclusions These findings support the importance of helping children and adolescents with inattention symptoms to engage in physical activity in suitable settings.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259367
Author(s):  
Vladislava Segen ◽  
Marios Avraamides ◽  
Timothy Slattery ◽  
Giorgio Colombo ◽  
Jan Malte Wiener

Online data collection offers a wide range of benefits including access to larger and more diverse populations, together with a reduction in the experiment cycle. Here we compare performance in a spatial memory task, in which participants had to estimate object locations following viewpoint shifts, using data from a controlled lab-based setting and from an unsupervised online sample. We found that the data collected in a conventional laboratory setting and those collected online produced very similar results, although the online data was more variable with standard errors being about 10% larger than those of the data collected in the lab. Overall, our findings suggest that spatial memory studies using static images can be successfully carried out online with unsupervised samples. However, given the higher variability of the online data, it is recommended that the online sample size is increased to achieve similar standard errors to those obtained in the lab. For the current study and data processing procedures, this would require an online sample 25% larger than the lab sample.


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