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LSD Test (lsd + test)
Selected AbstractsStability and Adaptability of Cultivars in Non-balanced Yield Trials.JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2002Comparison of Methods for Selecting, High Oleic' Sunflower hybrids for Grain Yield, Quality Abstract The best-yielding and most stable cultivars are identified by growing cultivars in different environments. The stability of grain-quality traits has been less thoroughly investigated than the stability of grain yield. High-oleic hybrids of sunflower have been available on the Argentinian seed market for several years. Research on the stability of these genotypes is scarce. The objectives of this work were (i) to compare, using three different methods, the stability and adaptability of high-oleic hybrids for grain yield and oil and oleic acid contents, and (ii) to explore the advantages and disadvantages of each method in selecting stable or adapted genotypes with high grain yield and high quality. Stability and adaptability analyses were performed on results for grain yields and oil and oleic acid contents of 35 high-oleic sunflower hybrids from 17 comparative yield trials conducted over 2 years in Argentina. Stability was estimated using two methods: Fisher's protected least significant difference (LSD) test, which compared hybrids with the best-yielding hybrid in each environment, and the test of relative yield (RY), which uses standard deviation as the measure of stability. Adaptability was estimated using Piepho's method of ,multiple comparisons with the best'. These three methods can be applied to unbalanced data. Piepho's method made little discrimination amongst the hybrids. The LSD and RY tests coincided in classifying the hybrids as stable and unstable in 85 % of cases for grain yield and 76 % for oil content. It is concluded that the most convenient method depends on characteristics of the experimental design and of variability of the evaluated trait. Results from the LSD test depend on the number of environments in which the cultivar is tested. The RY method is valuable for classifying some cultivars as high-yielding and stable, avoiding the problem of high-yielding environments biasing the general average. Use of both methods together could be effective for classifying hybrids when the number of environments is adequate. Zusammenfassung Stabilität und Adaptabilität von Kultivaren in nicht balancierten Ertragsversuchen. Methodenvergleich für Kornertrag und Qualität in ölsäurereichen-Sonnenblumen Höchste Erträge und Stabilität von Kultivaren werden durch Teste in verschiedenen Umwelten ermittelt. Stabilität der Qualitätseigenschaften des Korns sind bisher weniger untersucht worden als Stabilität des Kornertrages. Ölsäurereiche Hybriden von Sonnenblumen sind auf dem argentinischen Saatgutmarkt während der letzten Jahre angeboten worden. Untersuchungen zur Stabilität dieser Genotypen sind selten. Ziele dieser Arbeit waren es (i) drei unterschiedliche Methoden im Hinblick auf ihre Eignung für die Messung von Stabilität und Adaptabilität von ölsäurereichen Hybriden hinsichtlich Kornertrag, Öl- sowie Ölsäuregehalte zu vergleichen, und (ii) die Vorteile und Nachteile dieser Methoden zu analysieren, die eine Selektion stabiler und angepasster Genotypen mit hohem Kornertrag und hoher Qualität erlauben. Eine Analyse für Stabilität und Adaptabilität wurden aufgrund der Ergebnisse für Kornertrag, Öl- sowie Ölsäuregehalte von 35 Sonnenblumen, als Hybriden mit hohem Ölgehalt, auf der Grundlage von 17 vergleichenden Ertragsversuchen, die während zwei Jahren in Argentinien durchgeführt wurden, vorgenommen. Die Stabilität wurde unter Verwendung von zwei Methoden bestimmt: Der ,protected-LSD-Test' von Fisher, mit dem die Hybriden mit ertragshöchsten in jeder Umwelt verglichen werden; ferner der Test mit einem Vergleich des relativen Ertrags (RY), bei dem die Standardabweichung als Maß für die Stabilität verwendet wird; schließlich wurde die Adatabilität mit Piephos Methode eines multiplen Vergleichs mit der Besten durchgeführt. Die drei Methoden können nicht bancierten Daten angewendet werden. Piephos Methode ergab eine geringe Diskrimination für die Hybriden. LSD und RY stimmten bei einer Klassifizierung der Hybriden als stabile und nicht stabile in 85 % der Fälle hinsichtlich Kornertrag und 76 % für Ölgehalt überein. Es wird angenommen, dass geeignetere Methoden von den Eigenschaften der Experimentstruktur und der Variabilität der bewerteten Eigenschaften abhängen. Die Ergebnisse des LSD-Tests sind von der Anzahl der Umwelten abhängig, in denen die Kultivare getestet wurden. Die RY-Methode ist wertvoll, um einige Kultivare als hochertragreich und stabil zu klassifizieren, wobei der Einfluss hochertragreicher Umwelten zum Gesamtmittelwirt vermieden wird. Eine gemeinsame Anwendung der beiden Methoden könnte nützlich sein, um Hybriden zu klassifizieren, wenn eine geeignete Anzahl von Umwelten gegeben ist. [source] Effect of disinfectants containing glutaraldehyde on bonding of a tri- n -butylborane initiated resin to dentineJOURNAL OF ORAL REHABILITATION, Issue 5 2002N. Baba The purpose of this study was to evaluate the effects of disinfectants on the bond strength of resin to dentine. The surface of bovine dentine was exposed to formaldehyde (FA) aqueous solutions, glutaraldehyde (GA) aqueous solutions, 2-hydroxyethyl methacrylate aqueous solutions (HEMA), a commercially available dentine primer (Gluma CPS desensitizer, GLUMA), isotonic sodium chloride solution (IS), and distilled water (DW), and placed in a humidor (HU) at 37 °C, or non-stored (baseline). All dentine surfaces were conditioned with a 10% citric acid and 3% ferric chloride solution (10-3 liquid), and then bonded to an acrylic rod with a self-curing adhesive resin (Super-Bond C&B). The mean tensile bond strengths determined 24 h after bonding were compared by analysis of variance (ANOVA) and Fisher's protected LSD test (n=5, P , 0·05). The exposure of dentine to IS, DW and HU for both 48 and 168 h resulted in a decrease in bond strength when compared with the baseline. The highest bond strengths after 168 h of exposure were obtained with 5% GA, 10% HEMA, and GLUMA, the values of which were equivalent to baseline and were significantly higher than that of FA. It is concluded that disinfectant pre-treatment with 5% GA or GLUMA stabilizes the bonding of tri- n -butylborane (TBB) initiated luting agent to bovine dentine conditioned with 10-3 liquid. [source] Melatonin inhibits growth of diethylstilbestrol-induced prolactin-secreting pituitary tumor in vitro: possible involvement of nuclear RZR/ROR receptorsJOURNAL OF PINEAL RESEARCH, Issue 4 2003Michal Karasek Abstract: Melatonin exerts a marked antiproliferative action in numerous experimentally-induced tumors in vivo as well as in both animal and human cell lines in vitro. However, the mechanisms of oncostatic action of melatonin is not clear, and the involvement of both membrane and nuclear receptors are suggested. Therefore, the aim of this study was to investigate effects of melatonin, and both agonist (CGP 52608), and antagonist (CGP 55644) of RZR/ROR nuclear receptors on the growth of diethylstilbestrol-induced rat prolactin-secreting pituitary tumor cells in vitro. Pituitary tumors were induced by subcutaneous implantation of a single silastic capsule containing 10 mg of diethylstilbestrol in 4-wk-old male Fischer 344 rats. Four months after the implantation of capsules the animals were killed by decapitation, pituitary tumors were aseptically removed, mechanically dispersed, and enzymatically digested with 0.2% collagenase and 0.2% hyaluronidase. The cells (6 × 105 cells/well) were incubated for 24 hr in the presence of melatonin, CGP 52608, CGP 55644 and CGP 55644 plus melatonin (at the concentrations of 107 and 10,9 m) at 37°C in the humidified atmosphere of 95% air and 5% CO2. The group with the addition of solvent only served as control. The growth of cell was measured using the EZ4U system. Statistical analysis was performed using ANOVA followed by LSD test. Both melatonin and CGP 52608 significantly suppressed growth of tumor cells in vitro in both used concentrations. CGP 55644 stimulated growth of tumor cells and blocked the inhibitory effects of melatonin in vitro. Results of the present study as well as other experimental evidence strongly support the hypothesis that both membrane and nuclear receptors are involved in the oncostatic action of melatonin, and indicate that nuclear signalling plays an important role in this process. [source] Effect of Casting Procedures on Screw Loosening in UCLA-Type AbutmentsJOURNAL OF PROSTHODONTICS, Issue 2 2006Stefania C. Kano DDS Background: Screw loosening of implant restorations continues to be a complication in implant prosthodontics. Screw joints are subjected to a loss of initially applied torque because of friction and component misfit. It has been suggested that the loss of applied torque is less in machined metal abutments than in cast plastic abutments. Purpose: This study compared the loss of applied torque (detorque) values in machined titanium and in cast UCLA-type abutments for external hex abutment/implant interface. Materials and Methods: Four groups of 12 samples each were evaluated: (1) machined titanium abutments, (2) premachined palladium abutments cast with palladium, (3) plastic abutments cast with nickel-chromium, and (4) plastic abutments cast with cobalt-chromium. Each abutment was torqued to 30 Ncm according to the manufacturer's instructions and detorqued three times. The mean loss of applied torque (detorque) was recorded as a percentage of the torque applied. Group means were calculated and compared using ANOVA and Tukey's LSD test. Results: Mean detorque values were (1) 92.3 ± 2.9%, (2) 81.6 ± 5.0%, (3) 86.4 ± 4.6%, and (4) 84.0 ± 7.0%. Machined abutments demonstrated significantly greater detorque values compared with all cast groups (p < 0.05). No significant differences were found among cast groups. Conclusion: Machined abutments retained a significantly greater percentage of torque compared with cast abutments. Casting procedures decrease the percentage of applied torque, which may influence final screw joint stability. [source] Degradation of repaired denture base materials in simulated oral fluidJOURNAL OF ORAL REHABILITATION, Issue 3 2000C.-T. Lin This in vitro study evaluates the degradation of repaired denture bases upon immersion in a simulated oral fluid. Denture base materials (Luciton 199®), after being repaired by Repair Material® and Triad®, using three different joint surface designs (butt, round and 45 ° bevel), were immersed onto 99·5 vol.% ethanol/water solution (with similar solubility parameter) for various amounts of time (0,72 h). The flexural loads of the six combination of groups were measured by the three-point bending tests using a universal testing machine. Acoustic emission (AE) during sample fracturing were processed using the MISTRA 2001 system. The fracture pattern and surface details of the interface were examined with a scanning electronic microscope (SEM). Data were analysed using three-way anova and Tukey LSD tests. SEM micrographs of the fracture interface were used to differentiate the fracture mode. The flexural loads (2·72±0·51 Kgf) of the round joint specimens were significantly higher (P<0·05) than those (butt: 1·66±0·38 Kgf, 45 ° bevel: 1·93±0·41 Kgf) of the other two designs. This corresponds to the microscopic examination in which more cohesive failure mode was found for the round joint group after storage. The flexural loads (2·54±0·39 Kgf) of the specimens repaired with Triad® were significantly higher (P<0·05) than those (1·59±0·40 Kgf) of specimens repaired with Repair Material®. Significant progressive reduction of the flexural load and/or AE signals of the specimens was noted in proportion to the length of time of the immersion in the simulated oral fluid. Mechanical strength of a denture base repaired with a round joint design and light-cured material is significantly higher after immersion in simulated oral fluid. 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