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Post Hoc Tukey's Test (post + hoc_tukey_test)
Selected AbstractsSmaller and more numerous harvesting gaps emulate natural forest disturbances: a biodiversity test case using rove beetles (Coleoptera, Staphylinidae)DIVERSITY AND DISTRIBUTIONS, Issue 6 2008Jan Klimaszewski ABSTRACT Aim To evaluate changes in the abundance, species richness and community composition of rove beetles (Coleoptera, Staphylinidae) in response to three configurations of experimental gap cuts and to the effects of ground scarification in early succession yellow birch-dominated boreal forest. In each experimental treatment, total forest removed was held constant (35% removal by partial cutting with a concomitant decrease in gap size) but the total number of gaps was increased (two, four and eight gaps, respectively), resulting in an experimental increase in the total amount of ,edge' within each stand. Location Early succession yellow birch-dominated forests, Quebec, Canada. Methods Pitfall traps, ANOVA, MIXED procedure in sas®, post hoc Tukey's adjustment, rarefaction estimates, sum-of-squares and distance-based multivariate regression trees (ssMRT, dbMRT). Results Estimates of species richness using rarefaction were highest in clearcut and two-gap treatments, decreased in smaller and more numerous gaps and were significantly higher in scarified areas than in unscarified areas. ANOVA indicated a significant impact of harvesting on the overall standardized catch. Post hoc Tukey's tests indicated that the total catch of all rove beetles was significantly higher in uncut forests than in the treated areas. Both sum-of-squares and distance-based multivariate regression trees indicated that community structure of rove beetles differed among treatments. Assemblages were grouped into (a) control plots, (b) four- and eight-gap treatments and (c) two-gap and clearcut treatments. Main conclusions Rove beetle composition responded significantly to increasing gap size. Composition among intermediate and small-sized gap treatments (four- and eight-gap treatments) was more similar to uncut control forests than were larger gap treatments (two-gap) and clearcuts. Effects of scarification were nested within the harvested treatments. When the total area of forest removed is held constant, smaller, more numerous gaps are more similar to uncut control stands than to larger gaps and falls more closely within the natural forest heterogeneity. [source] The effects of chronic administration of sumatriptan and dipyrone on serotonergic system in the rat brain: an immunohistochemical studyACTA NEUROLOGICA SCANDINAVICA, Issue 4 2009E. Genē Objective,,, To investigate the effects of chronic high dose sumatriptan and dipyrone treatment on central serotonergic system in rats. Materials and methods,,, Male Sprague,Dawley rats (seven per group) were daily injected with sumatriptan (3 mg/kg), dipyrone (400 mg/kg) or saline for 30 days. The brains of animals were surgically removed and immunohistochemically stained for serotonin. Serotonin-positive stained cells were counted automatically by using a computerized image analysis program. Statistical analysis carried out using one-way ANOVA followed by post hoc Tukey test. Results,,, A significant decrease in serotonin-positive cells in the brainstem was observed after chronic sumatriptan administration while chronic use of dipyrone induced a significant increase in serotonin-positive cells both in the cortex and midbrain. Conclusion,,, Our data suggest that central serotonergic system might be modified by chronic use of sumatriptan and dipyrone. [source] Original article: Glass transition temperature of hard chairside reline materials after post-polymerisation treatmentsGERODONTOLOGY, Issue 3 2010Vanessa M. Urban doi:10.1111/j.1741-2358.2009.00312.x Glass transition temperature of hard chairside reline materials after post-polymerisation treatments Objective:, This study evaluated the effect of post-polymerisation treatments on the glass transition temperature (Tg) of five hard chairside reline materials (Duraliner II-D, Kooliner-K, New Truliner-N, Ufi Gel hard-U and Tokuso Rebase Fast-T). Materials and methods:, Specimens (10 × 10 × 1 mm) were made following the manufacturers' instructions and divided into three groups (n = 5). Control group specimens were left untreated. Specimens from the microwave group were irradiated with pre-determined power/time combinations, and specimens from the water-bath group were immersed in hot water at 55°C for 10 min. Glass transition (°C) was performed by differential scanning calorimetry. Data were analysed using anova, followed by post hoc Tukey's test (, = 0.05). Results:, Both post-polymerisation treatments promoted a significant (p < 0.05) increase in the Tg of reline material K. Materials K, D and N showed the lowest Tg (p < 0.05). No significant difference between T and U specimens was observed. Conclusion:, Post-polymerisation treatments improved the glass transition of material Kooliner, with the effect being more pronounced for microwave irradiation. [source] The effect of pH on surface hardness and microstructure of mineral trioxide aggregateINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2008M. S. Namazikhah Abstract Aim, To evaluate the surface microhardness of mineral trioxide aggregate (MTA) specimens following exposure of their surface to a range of acidic environments during hydration. In addition, the morphological microstructure features of samples were studied by scanning electron microscopy (SEM). Methodology, White ProRoot MTA (Dentsply Tulsa Dental, Johnson City, TN, USA) was mixed and packed into cylindrical polycarbonate tubes. Four groups, each of 10 specimens, were formed using a pressure of 3.22 MPa and exposed to pH 4.4, 5.4, 6.4 and 7.4, respectively, for 4 days. Vickers microhardness of the surface of each specimen was measured after exposure. Four groups of two specimens were prepared and treated in the same way prior to qualitative examination by SEM. Data were subjected to one-way anova and post hoc Tukey's test. Result, The greatest mean surface hardness values (53.19 ± 4.124) were observed following exposure to pH 7.4 with the values decreasing to 14.34 ± 6.477 following exposure to pH 4.4. The difference between these values at the 95% CI (33.39,44.30) was statistically significant (P < 0.0001). There were no distinct morphological differences between groups in terms of the internal microstructure. However, a trend was observed that the more acidic the solution, the more extensive the porosity of the specimens. Conclusion, Under the conditions of this study, surface hardness of MTA was impaired in an acidic environment. [source] | ||||||||||