Analysis of shade and temperature effects on assimilate partitioning in the everbearing strawberry 'Everest' as the basis for optimised long-season fruit production

Growth patterns and cropping were evaluated over the season for the everbearing strawberry 'Everest' at a range of temperatures (15-27degreesC) in two light environments (ambient and 50% shade). The highest yield was recorded for unshaded plants grown at 23degreesC, but the optimum temperature for vegetative growth was 15degreesC. With increasing temperature fruit number increased, but fruit weight decreased. Fruit weight was also significantly reduced by shade, and although 'Everest' showed a degree of shade tolerance in vegetative growth, yield was consistently reduced by shade. Shade also reduced the number of crowns developed by the plants over the course of the season, emphasising that crown number was ultimately the limiting factor for yield potential. We conclude that, in contrast to Junebearers which partition more assimilates to fruit at temperatures around 15degreesC (Le Miere et al., 1998), optimised cropping in the everbearer 'Everest' is achieved at the significantly higher temperature of 23degreesC. These findings have significance for commercial production, in which protection tends to reduce light levels but increase average temperature throughout the season.

Photosynthetic activity and early growth of four Cacao genotypes as influenced by different shade regimes under West African dry and wet season conditions

The physiological performance of four cacao clones was examined under three artificial shade regimes over the course of a year in Ghana. Plants under light shade had significantly higher photosynthetic rates in the rainy seasons whereas in the dry season there was a trend of higher photosynthetic rates under heavy shade. The results imply that during the wet seasons light was the main limiting factor to photosynthesis whereas in the dry season vapour pressure deficit was the major factor limiting photosynthesis through stomatal regulation. Leaf area was generally lower under heavier shade but the difference between shade treatments varied between clones. Such differences in leaf area allocation appeared to underlie genotypic differences in final biomass production in response to shade. The results suggest that shade for young cacao should be provided based on the current ambient environment and genotype.

The influence of shade and organic fertilizer treatments on the physiology and establishment of Theobroma cacao clones

Aims: This experiment aimed to determine whether the soil application of organic fertilizers can help the establishment of cacao and whether shade alters its response to fertilizers. Study Design: The 1.6 ha experiment was conducted over a period of one crop year (between April 2007 and March 2008) at the Cocoa Research Institute of Ghana. It involved four cacao genotypes (T 79/501, PA 150, P 30 [POS] and SCA 6), three shade levels (‘light’, ‘medium’ and ‘heavy’) and two fertilizer treatments (‘no fertilizer’, and ‘140 kg/ha of cacao pod husk ash (CPHA) plus poultry manure at 1,800 kg/ha). The experiment was designed as a split-plot with the cacao genotypes as the main plot factor and shade x fertilizer combinations as the sub-plots. Methodology: Gliricidia sepium and plantains (Musa sapientum) were planted in different arrangements to create the three temporary shade regimes for the cacao. Data were collected on temperature and relative humidity of the shade environments, initial soil nutrients, soil moisture, leaf N, P and K+ contents, survival, photo synthesis and growth of test plants. Results: The genotypes P 30 [POS] and SCA 6 showed lower stomatal conductance under non-limiting conditions. In the rainy seasons, plants under light shade had the highest CO2 assimilation rates. However, in the dry season, plants under increased shade recorded greater photosynthetic rates (P = .03). A significant shade x fertilizer interaction (P = .001) on photosynthesis in the dry season showed that heavier shade increases the benefits that young cacao gets from fertilizer application in that season. Conversely, shade should be reduced during the wet seasons to minimize light limitation to assimilation. Conclusion: Under ideal weather conditions young cacao exhibits genetic variability on stomatal conductance. Also, to optimize plant response to fertilizer application shade must be adjusted taking the prevailing weather condition into account.

Heat tolerance and the effects of shade on the behavior of Simmental bulls on pasture

The objectives were to assess the degree of thermolysis capacity as a characteristic of heat tolerance of the Simmental beef cattle and evaluate the effects of shade and shade type (artificial: AS, trees: TS, or no shade: NS) on daily behavior patterns during summer. Black globe temperature (BGT) was different under the two types of shade (P < 0.05) and was lower under the TS (P < 0.01) and under AS (P > 0.01) than average BGT in the sun. Animals when in AS used more intensely the shade (P = 0.002) mostly lying down under it (10.00-14.00 hours), while time standing was similar (P = 0.107) between TS and NS. Bulls without shade (NS) spent significantly more time at the water trough and most part of the day standing idle (72.4%, 10.1 h/14 h). TS bulls spent more time grazing/standing (P < 0.001). The Simmental bulls that were in TS and AS spent more time ruminating than bulls that stay without shade (NS). The availability of shade changes grazing, rumination and idling behavior of cattle in response to environmental conditions. Shade provided by trees can be more efficient than artificial shading as cattle spent more time grazing when tree shade was available. Thermolysis capacity can be used to select heat-tolerant animals.

EPR in the Characterization of the Shade Effect on Translucence, Remaining Free Radicals, and Polymerization Depth of Commercially Available Resin Composites

The aim of this study was to assess the relation between the number of free radicals generated and the polymerization depth in two different commercial brands of resin composites with different colors and translucence. Electron paramagnetic resonance quantified the radical populations through relative intensity (I (r)) of free radicals generated, and radical decay was monitored. Sample translucence and the classical polymerization depth were measured. The analysis indicated that resin with more color pigments (MA4, I (r) = 0.73 a.u) or more opacity components (ODA2, I (r) = 0.84 a.u) generated smaller populations of free radicals and have the lower polymerization depth than clearer (M, I (r) = 1.20 a.u and MA2, I (r) = 1.02) or more translucent (OEA2, I (r) = 1.00 a.u) composites for the same light-curing time. It seems that irradiation doses have to be adequate to more colored and less translucent resins.

Physiologic and productive responses of Holstein dairy cows with access to the constant or limited shade

The work: was carried out to evaluate the physiologic and productive responses of 16 Holstein breed cows, in different lactating stages and production levels, maintained in two free stall corral types, with or without plastic sheet covering, in the southeast-northwest of the covered area edges. The animals were confined in free stall system, during the months of the summer, with access to the constant or Limited shade. A complete randomized experimental design was: used. The physiological variables measured were respiratory frequency (morning an afternoon) and rectal temperature (morning and afternoon). The productive variables were milk production (morning, afternoon and daily), dry matter (DM) intake (% live weight) and efficiency of milk production (kg of milk/kg DM intake). The animals with access to the constant shade presented respiratory frequency (74.1 vs 81.0 breath/min.) and rectal temperature (39.5 vs 39.7 degrees C) lower and mirk production (22.6 vs 20.9 kg/day) and efficiency of milk production (1.3 vs 1.2 kg of milk/kg DM ingested) higher than the animals with access to the limited shade. There was no effect on the dry matter intake.

Influence of the Light-Curing Unit, Storage Time and Shade of a Dental Composite Resin on the Fluorescence

The aim of this study was to determine the influence of three light-curing units, storage times and colors of the dental composite resin on the fluorescence. The specimens (diameter 10.0 +/- 0.1 mm, thickness 1.0 +/- 0.1 mm) were made using a stainless steel mold. The mold was filled with the microhybrid composite resin and a polyethylene film covered each side of the mold. After this, a glass slide was placed on the top of the mold. To standardize the top surface of the specimens a circular weight (1 kg) with an orifice to pass the light tip of the LCU was placed on the top surface and photo-activated during 40 s. Five specimens were made for each group. The groups were divided into 9 groups following the LCUs (one QTH and two LEDs), storage times (immediately after curing, 24 hours, 7 and 30 days) and colors (shades: A(2)E, A(2)D, and TC) of the composite resin. After photo-activation, the specimens were storage in artificial saliva during the storage times proposed to each group at 37 C and 100% humidity. The analysis of variance (ANOVA) and Tukey's post-hoc tests showed no significant difference between storage times (immediately, 24 hours and 30 days) (P > 0.05). The means of fluorescence had difference significant to color and light-curing unit used to all period of storage (P < 0.05). The colors had difference significant between them (shades: A2D < A2E < TC) (P < 0.05). The Ultraled (LED) and Ultralux (QTH) when used the TC shade showed higher than Radii (LED), however to A2E shade and A2D shade any difference were found (P > 0.05).

Ex vivo evaluation of the effectiveness of bleaching agents on the shade alteration of blood-stained teeth

Aim To evaluate ex vivo effectiveness of the three formulations of bleaching materials for intracoronal bleaching of root filled teeth using the walking bleach technique.Methodology Extracted premolar teeth were stained artificially with human blood. After biomechanical preparation, the root canals were filled and a 3-mm thick intermediate base of zinc phosphate cement was placed at the level of the cementoenamel junction. The teeth were divided into four groups (n = 12): C (control, without bleaching material), A1 (sodium perborate + distilled water), A2 (sodium perborate + 10% carbamide peroxide) and A3 (sodium perborate + 35% carbamide peroxide). The bleaching materials were changed at 7 and 14 days. Evaluation of shade was undertaken with aid of the VITA Easyshade (TM) (Delta E*ab) and was performed after tooth staining and at 7, 14 and 21 days after bleaching, based on the CIELAB system. Data were analysed by ANOVA for repeated measurements, Tukey and Dunnett tests (alpha = 0.05).Results The Tukey test revealed that group A1 (10.58 +/- 4.83 Delta E*ab) was statistically different from the others (A2, 19.57 +/- 4.72 Delta E*ab and A3, 17.58 +/- 3.33 Delta E*ab), which were not different from each other. At 7 days: A1 was significantly different from A2; at 14 and 21 days: A2 and A3 were significantly better than A1; the Dunnett test revealed that the control group was different from A1, A2 and A3 at all periods (P < 0.05).Conclusion Sodium perborate associated with both 10% and 35% carbamide peroxide was more effective than when associated with distilled water.

Effect of Cement Shade and Light-curing Unit on Bond Strength of a Ceramic Cemented to Dentin

Purpose: To evaluate the effect of cement shade, light-curing unit, and water storage on tensile bond strength (a) of a feldspathic ceramic resin bonded to dentin.Materials and Methods: The dentin surface of 40 molars was exposed and etched with 37% phosphoric acid, then an adhesive system was applied. Forty blocks of feldspathic ceramic (Vita VM7) were produced. The ceramic surface was etched with 10% hydrofluoric acid for 60 s, followed by the application of a silane agent and a dual-curing resin cement (Variolink II). Ceramic blocks were cemented to the treated dentin using either A3 or transparent (Tr) shade cement that was activated using either halogen or LED light for 40 s. All blocks were stored in 37 degrees C distilled water for 24 h before cutting to obtain non-trimmed bar-shaped specimens (adhesive area = 1 mm(2) +/- 0.1) for the microtensile bond strength test. The specimens were randomly grouped according to the storage time: no storage or stored for 150 days in 37 degrees C distilled water. Eight experimental groups were obtained (n = 30). The specimens were submitted to the tensile bond strength test using a universal testing machine at a crosshead speed of 1 mm/min. The data were statistically analyzed using ANOVA and Tukey's post-hoc tests (alpha = 0.05).Results: The mean bond strength values were significantly lower for the corresponding water stored groups, except for the specimens using A3 resin cement activated by halogen light. There was no significance difference in mean bond strength values among all groups after water storage.Conclusion: Water storage had a detrimental effect under most experimental conditions. For both cement shades investigated (Tr and A3) under the same storage condition, the light-curing units (QTH and LED) did not affect the mean microtensile bond strengths of resin-cemented ceramic to dentin.

Shade level effects on yield and chemical composition of the leaf essential oil of Pothomorphe umbellata (L.) Miquel

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Analysis of camphorquinone in composite resins as a function of shade

Objective. To identify and quantify the camphorquinone (CQ) used in different brands of composite resins as a function of the shade analyzed.Materials and methods. Filtek Z250 A3 (FZA3), Filtek Z-250 Incisal (FZI), Pyramid Enamel A1 (PEA1), Pyramid Enamel Translucent (PET), Filtek Supreme A3E (FSA3) and Filtek Supreme GT (FSGT) were used. Five hundred milligrams of each resin were weighed and then dissolved in 1.0 ml of methanol. The samples were centrifuged to accelerate the sedimentation of the inorganic particles. 0.8 ml of the supernatant solution was collected with a pipette and assessed under gas chromatography coupled to the mass spectrometer (GC-MS). The results were compared to pure CQ solutions, used as a standard. Student's t-test, (p = 0.05) significant at the level of 5%, compared the results of each brand shade.Results. A smaller amount of camphorquinone was found in Filtek Z-250 (FZI) resin incisal shade when compared to (FZA3) A3 shade. on the other hand, Filtek Supreme resin featured a statistically larger camphorquinone amount in the incisal shade. in Pyramid Enamel resin camphorquinone was found only in shade Al, while the photoinitiator used in the Translucent shade was not identified.Significance. Based on the data obtained, it is possible to conclude that a single composite resin brand may feature differences in amount and type of photoinitiator used. (C) 2006 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Assessment of color fidelity of several composite resins compared to their Vita Classical shade registration

This study compared the color fidelity of different composite resins with their registration in the Vita Classical Shade Guide. Using a prefabricated Teflon mold, 120 specimens were divided into four groups fn - 30), according to the resin tested. Three subgroups (a = 10) were prepared for each resin group; these subgroups tested enamel shade, dentin shade, and enamel and dentin shade. Three measurements were performed to verily whether the tooth shade matched that of the Vita Classical Shade Guide. The color was evaluated and the shade variations were calculated. The data were submitted to a three-way AN OVA test (time, color match, and composite type), followed by Tukey's test. It was concluded that all composite resins showed color differences in relation to the Vita Classical Shade Guide.