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Concept: Tukey's range test

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PURPOSE: To compare the short-term effects of a neurodynamic sliding technique versus control condition on hamstring flexibility in healthy, asymptomatic male soccer players. SUBJECTS: Twenty-eight young male soccer players from Palencia, Spain (mean age 20.7 yrs ± 1.0, range 19-22) with decreased hamstring muscle flexibility. METHODS: Subjects were randomly assigned to one of two groups: neurodynamic sliding intervention or no intervention control. Each subject’s dominant leg was measured for straight leg raise (SLR) range of motion (ROM) pre- and post-intervention. Subjects received interventions as per group allocation over a 1 week period. Data were analyzed with a 2 (intervention: neurodynamic and control) × 2 (time: pre and post) factorial ANOVA with repeated measures and appropriate post-hoc analyses. RESULTS: A significant interaction was observed between intervention and time for hamstring extensibility, F(1,26) = 159.187, p < .0005. There was no difference between the groups at the start, p = .743; however, at the end of the study, the groups were significantly different with more range of motion in the group that received neurodynamic interventions, p = .001. The group that received neurodynamic interventions improved significantly over time (p < .001), whereas the control group did not (p = .684). CONCLUSION: Findings suggest that a neurodynamic sliding technique can increase hamstring flexibility in healthy, male soccer players.

Concepts: Time, Scientific method, Experimental design, Design of experiments, Analysis of variance, Straight leg raise, Tukey's range test

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This study investigated the effects of high-intensity interval training (HIIT) and β-hydroxy-β-methylbutyric free acid (HMB) supplementation on physical working capacity at the onset of neuromuscular fatigue (PWCFT). Thirty-seven participants (22 men, 15 women; 22.8±3.4y) completed an incremental cycle-ergometer test (GXT); electromyographic amplitude from the right vastus lateralis was recorded. Assessments occurred preceding (PRE) and following 4-weeks of supplementation (POST). Participants were randomly assigned to control (C, n=9), placebo (P, n=14), or supplementation (S, n=14) groups. Both P and S completed 12 HIIT sessions, while C maintained normal diet and activity patterns. PWCFT (W) was determined using a DMAX (maximal perpendicular distance) method. Electromyographic amplitude (µVrms) over time was used to generate a cubic regression. Onset of fatigue (TF) was the x-value of the point on the regression that was at DMAX from a line between the first and last data points. PWCFT was estimated using TF and GXT power-output increments. The two-way ANOVA (group × time) resulted in a significant interaction for PWCFT (F=6.69, p=0.004). Post-hoc analysis with one-way ANOVA resulted in no difference in PWCFT among groups at PRE (F=0.87, p=0.43), however, a difference in PWCFT was shown for POST (F=5.46, p=0.009). Post-hoc analysis among POST values revealed significant differences between S and both P (p=0.034) and C (p=0.003). No differences (p=0.226) were noted between P and C. Paired samples t-tests detected significant changes following HIIT for S (p<0.001) and P (p=0.016), but no change in C (p=0.473). HIIT increased PWCFT, but HMB with HIIT was more effective than HIIT alone. Further, it appears that adding HMB supplementation with HIIT in untrained men and women may further improve endurance performance measures.

Concepts: Statistical tests, Statistics, Normal distribution, Analysis of variance, High-intensity interval training, Interval training, F-test, Tukey's range test

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In this data article, we present a comprehensive dataset on electrical energy consumption in a university that is practically driven by Information and Communication Technologies (ICTs). The total amount of electricity consumed at Covenant University, Ota, Nigeria was measured, monitored, and recorded on daily basis for a period of 12 consecutive months (January-December, 2016). Energy readings were observed from the digital energy meter (EDMI Mk10E) located at the distribution substation that supplies electricity to the university community. The complete energy data are clearly presented in tables and graphs for relevant utility and potential reuse. Also, descriptive first-order statistical analyses of the energy data are provided in this data article. For each month, the histogram distribution and time series plot of the monthly energy consumption data are analyzed to show insightful trends of energy consumption in the university. Furthermore, data on the significant differences in the means of daily energy consumption are made available as obtained from one-way Analysis of Variance (ANOVA) and multiple comparison post-hoc tests. The information provided in this data article will foster research development in the areas of energy efficiency, planning, policy formulation, and management towards the realization of smart campuses.

Concepts: Electricity, Statistics, Variance, Multiple comparisons, Analysis of variance, Potential energy, Electrical engineering, Tukey's range test

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[Purpose] The purpose of this study was to investigate the effect of pelvic tilt angles and lung function in participants performing pelvic tilts on a ball. [Subjects and Methods] Eighteen subjects participated in this study. While they performed pelvic tilt on sitting at a ball, the peak expiratory flow (PEF) and forced expiratory volume in one second (FEV1) were measured at 10 degrees of anterior and posterior pelvic tilt, respectively, and neutral position. The repeated measure ANOVA was performed, and the Bonferroni correction was used for post-hoc analysis. [Results] The PEF of the participants was significantly higher at neutral position, compared with an anterior pelvic tilt at 10 degrees. The FEV1 was also higher in neutral position, compared with anterior and posterior pelvic tilt. [Conclusion] This study underlines the need for the standardization of the FVC testing protocol for positioning the pelvic angle in a neutral position in patients with respiratory disorders to promote reliable interpretation of intervention outcomes.

Concepts: Pulmonology, Asthma, Respiratory physiology, Integral, Spirometry, Vital capacity, Peak flow meter, Tukey's range test

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The aim of this study was to evaluate the influence of different concentrations of hydrofluoric acid (HF) associated with varied etching times on the microshear bond strength (μSBS) of a resin cement to a lithium disilicate glass ceramic. Two hundred seventy-five ceramic blocks (IPS e.max Press [EMX], Ivoclar Vivadent), measuring 8 mm × 3 mm thickness, were randomly distributed into five groups according to the HF concentrations (n=50): 1%, 2.5%, 5%, 7.5%, and 10%. Further random distribution into subgroups was performed according to the following etching times (n=10): 20, 40, 60, 120, and 20 + 20 seconds. After etching, all blocks were treated with a silane coupling agent followed by a thin layer of an unfilled resin. Three resin cement cylinders (∅=1 mm) were made on each EMX surface, which was then stored in deionized water at 37°C for 24 hours before testing. The μSBS was in a universal testing machine at a crosshead speed of 1 mm/min until failure. Data were submitted to two-way analysis of variance, and multiple comparisons were performed using the Tukey post hoc test (α=0.05). One representative EMX sample was etched according to the description of each subgroup and evaluated using scanning electron microscopy for surface characterization. The HF concentrations of 5%, 7.5%, and 10% provided significantly higher μSBS values than 1% and 2.5% (p<0.05), regardless of the etching times. For 1% and 2.5% HF, the etching times from 40 to 120 seconds increased the μSBS values compared with 20 seconds (p<0.05), but etching periods did not differ within the 5%, 7.5%, and 10% HF groups (p>0.05). The effect of re-etching was more evident for 1% and 2.5% HF (p<0.05). Different HF concentrations/etching times directly influenced the bond strength and surface morphology of EMX.

Concepts: Electron, Materials science, Analysis of variance, Scanning electron microscope, Tests, Universal testing machine, Test fixture, Tukey's range test

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A full-size manikin dressed in fire-resistant coveralls coated in 120 grams of sodium bicarbonate was randomly given one of three treatments for dry aerosol decontamination. The three treatments were high-efficiency particulate air (HEPA) vacuum, a commercially-available air shower, and the no treatment control. Immediately after the treatment, the coveralls were doffed and an air sample was taken in the breathing zone of the manikin to estimate airborne total and respirable dust concentrations to an unprotected worker post decontamination. Each treatment was applied four times for a total of 12 trials. Using analysis of variance (ANOVA) with alpha = .05 and Tukey’s Honestly Significant Difference multiple comparison post-test, it was determined that HEPA vacuuming was not significantly different from the air shower for respirable dust, but only the air shower was significantly better than no decontamination (p = .037). For total dust, HEPA was not significantly different from the air shower, but both were significantly better than no treatment (p = .007, p = .004, respectively).

Concepts: Variance, Normal distribution, Multiple comparisons, Analysis of variance, Particulate, F-test, Tukey's range test, Vacuum cleaner

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[Purpose] The purpose of this study was to investigate interface pressure redistribution in healthy volunteers when applying different cushions and anterior wedge heights. [Subjects and Methods] This study included 36 healthy individuals in their 20s. The peak and mean pressures were measured by applying different cushions and anterior wedge heights. The results were analyzed by using a one-way analysis of variance and post-hoc analysis. [Results] The peak and mean pressures were statistically significant based on the cushion types and anterior wedge height. The peak pressure was at its highest and lowest when sitting on a 6-cm anterior wedge and a foam cushion, respectively. The mean pressure was greatest when sitting on a 6-cm anterior wedge of a firm surface and smallest when sitting on a 5 cm foam cushion. [Conclusion] This study shows that the most effective method for pressure redistribution was sitting on a 5 cm foam cushion without an anterior wedge.

Concepts: Statistical tests, Statistics, Data analysis, Probability theory, Standard deviation, Analysis of variance, Chair, Tukey's range test

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This study aimed to assess the amount of plate waste and how plate waste was disposed by early adolescent girls using a mobile food record (mFR). Participants were girls nine to thirteen years residing in O'ahu, Hawai'i (n = 93). Foods selected and leftover were estimated using a three day mFR. Each leftover food was then classified as thrown into the trash, fed to a pet, eaten later, or other (e.g., composted). Repeated measures analyses of variance (ANOVA) were conducted and Tukey’s post-hoc test were used to adjust for multiple comparisons between times (breakfast, lunch, dinner, and snack) on leftover food and leftover food thrown into the trash. The percentage of food leftover and thrown into the trash was highest at lunch. The percentage of protein, grain, vegetables, fruit, and dairy leftover at lunch were unexpectedly low compared to previous studies. The median for percentage of food thrown into the trash at lunch was <5% for all food groups, and was consistently low across the day (<10%). Average energy intake was 436 kcal (±216) at lunch, and 80% of caregivers reported total household income as ≥$70,000. Studies in real-time using technology over full days may better quantify plate waste among adolescents.

Concepts: Normal distribution, Multiple comparisons, Analysis of variance, Recycling, Household income in the United States, Meal, Dinner, Tukey's range test

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Heterogeneous findings across studies of structural abnormality in schizophrenia (SZ) have impeded the development a unified theory of white matter pathology. As a cardinal symptom of SZ, auditory verbal hallucination (AVH) has been suspected to be associated with improper communication among several brain regions, which might indicated white matter pathology. Participants comprised 25 first-episode (FE) patients with AVH, 25 patients without AVH and 25 healthy subjects. Diffusion tensor imaging (DTI) measures were calculated using the TBSS of FSL. Voxel-based ANOVA tests were performed among the three groups and threshold-free cluster enhancement (TFCE) method correction was used for multiple comparisons. Voxel-based one-way ANOVA showed significant group effects for fractional anisotropy (FA) and radial diffusivity (RD) values. Post-hoc t-tests indicated that schizophrenia patients had lower FA and higher RD values in the internal capsule and anterior corona radiata than control subjects. Post-hoc analyses exhibited more widespread fiber disruptions in AVH patients than non-AVH patients. These results hinted on the important role of projection fiber disruption in schizophrenia patients. In addition, the current study also suggested that direct comparison between studies using patients with different symptom profiles should be interpreted with caution.

Concepts: Statistical tests, Schizophrenia, Hallucination, Psychosis, Multiple comparisons, Analysis of variance, Imaging, Tukey's range test

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Brucellosis in cattle and humans has received world-wide research attention as a neglected and re-emerging zoonotic disease with many routes of transmission. Studies of brucellosis in Uganda have emphasized occupational exposures and also revealed variations in prevalence levels by region and cattle production systems. To date, research linking pastoralist household income from dairy production to brucellosis and its transmission risk pathways do not exist in Uganda. We assessed whether spatial differences in unit milk prices can be explained by brucellosis prevalence in cattle along a distance gradient from Lake Mburo National Park in Uganda. Semi-structured interviews administered to 366 randomly selected household heads were supplemented with serological data on brucellosis in cattle. Statistical analysis included Pearson correlation test, multiple regression and analysis of variance (ANOVA) using SPSS version 17. Serological results showed that 44% of cattle blood samples were sero-positive for brucellosis. The results obtained from interviews put the statistical mean of household reported cattle abortions at 5.39 (5.08-5.70 at 95% CI, n=366). Post-hoc analysis of variance revealed that both sero-positive cattle and reported cattle abortions significantly were much lower when moving outwards from the park boundary (p<0.05), while the price of milk increased significantly (p<0.05) along the same distance gradient. Further studies should identify public and private partnerships needed to create and strengthen good zoonotic brucellosis management practices at the nexus of wildlife and livestock in Uganda.

Concepts: Regression analysis, Epidemiology, Statistics, Milk, Pearson product-moment correlation coefficient, Standard deviation, Analysis of variance, Tukey's range test