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Bootstrap Methods and Permutation Tests
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... We thus chose to analyze data from the Individual sample using a combination of randomization tests and standard parametric tests. Randomization tests can perform better than conventional statistics for small samples and when it is unknown whether the data has a normal distribution (Hesterberg et al., 2003;Craig and Fisher, 2019). We wrote randomization tests in Python (attached: UEDRandomization.py). ...
... Craig and Fisher, 2019). We used permutations of the data as is appropriate when looking for significance (Hesterberg et al., 2003) with 10,000 permutations per test. Each permutation took the measured values and redistributed them randomly between students (see below). ...
Active learning approaches to biology teaching, including simulation-based activities, are known to enhance student learning, especially of higher-order skills; nonetheless, there are still many open questions about what features of an activity promote optimal learning. Here we designed three versions of a simulation-based tutorial called Understanding Experimental Design that asks students to design experiments and collect data to test their hypotheses. The three versions vary the experimental design task along the axes of feedback and constraint, where constraint measures how much choice students have in performing a task. Using a variety of assessments, we ask whether each of those features affects student learning of experimental design. We find that feedback has a direct positive effect on learning. We further find that small changes in constraint have only subtle and mostly indirect effects on learning. This work suggests that designers of tools for teaching higher-order skills should strive to include feedback to increase impact and may feel freer to vary the degree of constraint within a range to optimize for other features such as the ability to provide immediate feedback and time-on-task.
... Spearman's rank correlation coefficient (ρ) was computed between average maps of WSS metrics and lesion prevalence in order to quantify similarities without assuming a linear relation. To assess statistical significance whilst avoiding problems caused by autocorrelation within the maps [41], confidence intervals (CIs) were computed for the correlation coefficients by bootstrapping [41][42][43][44], as outlined in Supplementary Material Appendix A. The correlation was deemed significant if the CI excluded 0. The same statistical approach was used when comparing WSS maps with and without branches, and WSS maps using different inlet velocity waveforms. ...
Purpose
The patchy anatomical distribution of atherosclerosis has been attributed to variation in haemodynamic wall shear stress (WSS). The consensus is that low WSS and a high Oscillatory Shear Index (OSI) trigger the disease. We found that atherosclerosis at aortic branch sites correlates threefold better with transverse WSS (transWSS), a metric which quantifies multidirectional near-wall flow. Coronary artery disease has greater clinical significance than aortic disease but computation of WSS metrics is complicated by the substantial vessel motion occurring during each cardiac cycle. Here we present the first comparison of the distribution of atherosclerosis with WSS metrics computed for moving coronary arteries.
Methods
Maps of WSS metrics were computed using dynamic geometries reconstructed from angiograms of ten non-stenosed human right coronary arteries (RCAs). They were compared with maps of fatty streak prevalence derived from a previous study of 1852 RCAs.
Results
Time average WSS (TAWSS), OSI, transWSS and the cross-flow index (CFI), a non-dimensional form of the transWSS, gave non-significant or significant but low spatial correlations with lesion prevalence. The highest correlation coefficient (0.71) was for the relative residence time (RRT), a metric that decreases with TAWSS and increases with OSI. The coefficient was not changed if RRT was calculated using CFI, which captures multidirectional WSS only, rather than OSI, which encompasses both multidirectional and oscillatory WSS.
Conclusion
Contrary to our earlier findings in the aorta, low WSS in combination with highly multidirectional flow correlates best with lesion location in the RCA, explaining approximately half of its anatomical variation.
... The means and standard errors of reproductive parameters were estimated using the bootstrap method and estimated for 100,000 individuals [67][68][69][70]. Differences in parameters between treatments were analyzed using the paired bootstrap test based on the confidence interval using the TWOSEX-MSChart program for Windows [62,[71][72][73][74]. ...
Spodoptera frugiperda control methods have proved to be inefficient, which justifies the search for new control measures. In this search for botanical insecticides for controlling S. frugiperda, the following were evaluated: (i) the toxicity of essential oils (EOs) from Cinnamodendron dinisii, Eugenia uniflora, and Melaleuca armillaris; (ii) the effect of EOs on life table parameters against S. frugiperda; (iii) the chemical characterization of EOs; and (iv) the in silico interaction of the chemical constituents present in the three EOs with the molecular targets of S. frugiperda. The EO from E. uniflora had the lowest LD 50 (1.19 µg of EO/caterpillar). The major compounds bicyclogermacrene (18.64%) in C. dinisii and terpinolene (57.75%) in M. armillaris are highly predicted to interact with the octopamine receptor (OctpR). The compound 1,8-cineole (21.81%) in M. armillaris interacts mainly with a tolerant methoprene receptor (MET) and curzerene (41.22%) in E. uniflora, which acts on the OctpR receptor. Minor compounds, such as nerolidol in C. dinisii and β-elemene in E. uniflora, are highly ranked for multiple targets: AChE, MET, OctpR, and 5-HT1. It was concluded that the EO from E. uniflora negatively affects several biological parameters of S. frugiperda development and is promising as an active ingredient in formulations for controlling this insect pest.
... Taking into account the initial sex ratio and more data on immature individuals, the bootstrap matching technique was employed to combine the immature data (e.g., survival and duration of each stage) and the adult data (e.g., adult longevity and daily fecundity of females) for the construction of a complete life table [44]. After basic analysis, the bootstrap technique was used with 10,000 resamples to estimate the standard errors of the population parameters [45][46][47][48][49]. Differences between the two strains were evaluated by the paired bootstrap test on the 95% confidence interval and t-intervals of 100,000 differences [50][51][52]. ...
Liriomyza trifolii is a significant invasive pest that targets horticultural and vegetable crops, causing large-scale outbreaks characterized by pronounced thermotolerance and insecticide resistance. This study examined the impact of long-term selection for abamectin resistance during the larval stage of L. trifolii on its population dynamics and thermal tolerance. We conducted a comprehensive comparison between the abamectin-resistant strain (AB-R) and the susceptible strain (S), including age-stage, two-sex life table analysis, thermal preference (Tpref), critical thermal maximum (CTmax), heat knockdown times (HKDTs), eclosion and survival rates, and LtHsp expression under heat stress. Our results showed that while selection for abamectin resistance was detrimental to survival and reproduction, it activated self-defense mechanisms and rapid adaptive adjustments and conferred modest thermal tolerance, which suggests a dual nature of insecticide effects. The AB-R strain exhibited significantly higher thermal preference and CTmax values, along with a longer HKDT and improved survival. Additionally, there was a significant upregulation of LtHsp expression in the AB-R strain compared to the S strain. These findings indicate that the evolution of thermal adaptation was accompanied by abamectin resistance development, emphasizing the necessity of considering temperature effects when applying chemical control. Our study provides valuable insights into how physiological acclimation may help mitigate the toxic effects of insecticides and illustrate how insects respond to multiple environmental pressures.
The sugar beet flea beetle, Cassida vittata Vill. is an invasive pest that significantly damages sugar beet crops in Morocco by affecting the leaves. To gain a deeper understanding of how temperature influences the development and reproduction of C. vittata and to facilitate its population management, laboratory-based experiments were conducted. Individuals were subjected to a range of constant temperatures spanning from 15°C to 36°C. The most extended lifespans for both adult females and males were recorded at 30°C, with respective longevities of 62.8 and 62.5 days. The highest likelihood of eggs maturing into the adult stage occurred at 25°C, with survival rates of 39.0% for females and 37.5% for males. Preadult survival rates displayed significant variability with temperature, with the highest survivorship observed at 25°C (76.5%). The maximum average number of offspring produced per female reached 225.1 eggs at 25°C. Daily reproduction, maximum total fecundity, and maximum daily fecundity were also notably higher at 25°C. The population growth parameters exhibited their most favorable values at 25°C, with r (0.0933 d-1), and R0 (87.15 offspring per female) being highest at this temperature. The temperature thresholds for the complete pre-adult stage (1st instar larva to adult) were estimated to be 9.4°C for females and 9.0°C for males. The thermal constants from the 1st instar larva to the adult stage were calculated to be 526.3 and 476.2 DD, respectively. These findings indicate that the most favorable temperature range for the population growth of this invasive pest falls between 25°C and 30°C.
Diaspis echinocacti (Bouché), is a notorious pest that infests cacti, causing serious damage. The developmental durations of various life stages, sex ratios, survival rates, fecundity, and population growth parameters of D. echinocacti were studied under temperature conditions ranging from 15 °C to 40 °C. Temperature significantly influenced the developmental periods, with the shortest durations observed at 25 °C. A decrease in female life cycle duration was observed from 15 °C (83.2 days) to 32 °C (26.4 days). Higher temperatures led to a decrease in the proportion of females in the population, with a sex ratio of 0.10 at 40 °C. Pre-adult survival rates showed an 83% survival rate at 25 °C which sharply declined to 21% at 32 °C and 7% at 40 °C. Parthenogenesis was not observed in females. Total pre-oviposition, and post-oviposition periods decreased with increasing temperature, with the longest oviposition period at 25 °C (37.7 days). The intrinsic rate of increase (r) was highest at 25 °C (0.09 d−1). Predicted fecundity for the next generation was highest at 25 °C (9947.2), followed by 20 °C (2349.0). The population trend index indicated a potential population increase of 49.7 times at 25 °C in the next generation. The estimated temperature threshold for the egg-to-adult development of females and males in D. echinocacti was 10.5 °C. For the cumulative development of females and males from egg to adult, the thermal constants were 400.0 DD and 357.1 DD, respectively. These findings highlight the effect of temperature on scale development, with implications for scale management.
To investigate the effect of an educational program on compliance with glove use in a pediatric emergency department.
Without their knowledge, participants were observed for routine use of gloves during vascular access procedures before and after an educational program. Participants with up to 3 years' vascular access experience were defined as less experienced and those with 4 or more years' experience were defined as more experienced. Their success rates performing vascular access procedures with and without wearing gloves were also monitored.
Inner-city pediatric hospital emergency department.
Twenty-three emergency department registered nurses.
A 30-minute lecture with slides, written materials, and posters addressing the reasons and need for universal precautions, and recommended methods of barrier precautions to prevent skin and mucous membrane exposure when handling sharp instruments.
For the less experienced registered nurses, the compliance rate before the educational program was 70% and remained at about 93% afterward. For the more experienced registered nurses, the compliance rate before the program was only 15%. After the program, this compliance rate rose to 93%, but declined to only 50% by the fifth month. The registered nurses' success rate on the first attempt at vascular access while wearing gloves was 75% compared with 70% without gloves.
Educational programs can result in a clinically significant increase in glove use by pediatric emergency department registered nurses. Long-term improvement was less pronounced for the group of more experienced registered nurses. We also observed that glove use does not appear to interfere with the proficient performance of vascular access procedures.
A randomized, double-blind, placebo-controlled trial was conducted to examine the effect of calcium supplementation on blood pressure in normotensive black (n = 21) and white (n = 54) men, aged 19 to 52 years. After a four-week baseline period of weekly blood pressure measurement, subjects were randomly assigned within racial groups to either a treatment (calcium, 1500 mg/d) or placebo group for a 12-week period. During the experimental period, multiple blood pressure measurements were taken every two weeks in both the seated and supine positions, using a random baseline sphygmomanometer. A repeated-measures analysis of covariance yielded a modest but significantly lower seated mean arterial pressure in the treatment group compared with the control group, but no differences between the races. Results were similar for supine blood pressure. Calcium supplementation, in comparison with placebo, resulted in lower mean arterial pressure in normotensive white and black men during a 12-week period. The overall blood pressure—lowering effect was not correlated with the response of serum levels of total and ionized calcium, total inorganic phosphorus, or parathyroid hormone, or overnight urinary electrolyte values.
(JAMA 1987;257:1772-1776)
Readability levels of magazine ads
- F K Shuptrine
- D D Mcvicker
F. K. Shuptrine and D. D. McVicker, "Readability levels of magazine ads,"
21, No. 5 (1981), p. 47.