906 resultados para Dry and rainy seasons
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This paper analyses the dew occurrence in Botucatu, Sao Paulo State, Brazil, in the period from 1971 to 1984. The phenomenon was observed on the grass plot of the Climatological Station in the 'Presidente Medici' Experimental Farm. The station is installed on soil 'Terra Roxa Estruturada', on a middle slope, declivity of 8% and east exposure. Days with dew were summed for the following periods: month, year, season, no rainy period and rainy period. For each period the following values were calculated: mean, mean standard errors and mean confidence interval. Also the absolute extreme values and the amplitude of variation were determined. The confidence interval of the mean were calculated by the 't' statistic, at the level of 5% of error probability. The means were compared by using the 't' statistic, at the level of 5% of error probability. The following table of values corresponds to the regime of dew occurrence in Botucatu, expressed in number of days with dew. The dew occurrence regime in Botucatu was analysed comparatively with the regime at Itatinga, in Sao Paulo State and with the regime of Rio Grande, in Rio Grande do Sul State. -English summary
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The objective of this study was to evaluate the performance of broilers reared under different population densities in the cold and hot seasons of the year. Two identical experiments were conducted, one during the winter for 49 days, and the other during the summer where the chicks were slaughtered at 42 days of age. Commercial Hubbard broiler-type chicks were distributed in a randomized block design in a 4 × 2 factorial arrangement with population densities of 10, 14, 18, and 22 birds/m 2, by sex, and with four replications. Feed intake was reduced with a progressive decrease of available space for the chicks, and it resulted in a linear decrease in weight gain. However, there was a linear increase in the live weight of broilers in kilograms per area of floor space, proportional to the increase of population density, without effect on the viability. The progressive increment in the population density reduced the observed feed/gain ratio during the total winter rearing period for both sexes. There was no effect of population density on this characteristic during the hot season of the year. Population density did not affect the carcass yield of chicks during the summer. However, there was a linear increase on carcass yield with an increase in population density in the winter. The males, at the age slaughtered, had higher weights, feed intakes, and better feed/gain ratios, and lower abdominal fat and higher live weight production in kilograms per floor area than females. However, the viable index for the males was lower. From the results obtained, there was a linear increase in the liveweight of broilers in kilograms per floor area, making it possible to rear broilers under higher population densities, independent of the season of the year, as well as the occurrence of a decrease in feed intake and weight gain of the chicks with a decrease of available space.
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Rain acidity may be ascribed to emissions from power station stacks, as well as emissions from other industry, biomass burning, maritime influences, agricultural influences, etc. Rain quality data are available for 30 sites in the South African interior, some from as early as 1985 for up to 14 rainfall seasons, while others only have relatively short records. The article examines trends over time in the raw and volume weighted concentrations of the parameters measured, separately for each of the sites for which sufficient data are available. The main thrust, however, is to examine the inter-relationship structure between the concentrations within each rain event (unweighted data), separately for each site, and to examine whether these inter-relationships have changed over time. The rain events at individual sites can be characterized by approximately eight combinations of rainfall parameters (or rain composition signatures), and these are common to all sites. Some sites will have more events from one signature than another, but there appear to be no signatures unique to a single site. Analysis via factor and cluster analysis, with a correspondence analysis of the results, also aid interpretation of the patterns. This spatio-temporal analysis, performed by pooling all rain event data, irrespective of site or time period, results in nine combinations of rainfall parameters being sufficient to characterize the rain events. The sites and rainfall seasons show patterns in these combinations of parameters, with some combinations appearing more frequently during certain rainfall seasons. In particular, the presence of the combination of low acetate and formate with high magnesium appears to be increasing in the later rainfall seasons, as does this combination together with calcium, sodium, chloride, potassium and fluoride. As expected, sites close together exhibit similar signatures. Copyright © 2002 John Wiley & Sons, Ltd.
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This study investigates the thrombocyte aggregation process in the South American fresh water turtle (Phrynopys hilarii) using electron microscopy. Blood was taken from surgically exposed lateral neck vessels often turtles Phrynopys hilarii during the spring and summer seasons, when the mean temperature is 37°C. Blood samples were fixed with Karnovsky solution for processing by transmission electron microscopy. The turtle thrombocytes were spindle-shaped with lobulated nuclei. Prominent vesicles and canaliculi were found throughout the cytoplasm. The cytoplasm organelles showed an agranular endoplasmatic reticulum, Golgi complex near the centrioles and scattered free ribosomes. These cells are similar to bird thrombocytes but distinct from fish and frog thrombocytes. Blood clotting time was 5 min ± 30 sec measured by the Lee and White method. Structural alterations resulting from the aggregation process occurred after activation. Thrombocytes developed numerous filopodial projections, an increased number of vacuoles and changed from spindle to spherical shape. P. hilarii thrombocytes have different morphologic characteristics compared to other non-mammalian vertebrate cells. These cells can participate in the aggregation process, as observed in birds.
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This study was accomplished with the objective of knowing the seasonal distribution of the main species of parasites causes of branchial damages to the fish from fee-fishing at Guariba, State of São Paulo. This city is situated at 21 degrees 15'22'' S, 48 degrees 18'58'' W, in altitude 595 meters. This research was conducted between April, 1997 to March, 1999. From 408 fishes examined, 29.1% of them were infested by the protozoans e metazoans. Leporinus macrocephalus showed the highest parasitism by Trichodina sp., although Piaractus mesopotamicus and Cyprinus carpio were also parasited. Piscinoodinium pillulare infestation were found in L. macrocephalus, P. mesopotamicus, C. carpio e Colossoma macropomum. Monogenetics metazoan have largely been observed in L. macrocephalus, P. mesopotamicus, C. carpio, C. macropomum e cross-bred tambacu. The incidence of this parasite was elevated in the summer for L. macrocephalus, spring for P. mesopotamicus and C. macropomum, and both seasons for cross-bred tambacu. Lernaea cyprinacea copepodes were observed in L. macrocephalus, P. mesopotamicus, C. carpio and cross- breeding tambacu, in spite of the fact that C. carpio has demonstrated high parasitism of adult form. The fish L. macrocephalus, P. mesopotamicus and C. carpio were sponged intensely by Dolops carvalhoi, in situation of high population density. Piaractus mesopotamicus was considered the species more parasited by myxosporídeos, that were also observed in L. macrocephalus and cross-breeding tambacu.
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The use of acid etchants to produce surface demineralization and collagen network exposure, allowing adhesive monomers interdiffusion and consequently the formation of a hybrid layer, has been considered the most efficient mechanism of dentin bonding. The aim of this study was to compare the tensile bond strength to dentin of three adhesive systems, two self-etching ones (Clearfil SE Bond - CSEB and One Up Bond F - OUBF) and one total-etching one (Single Bond - SB), under three dentinal substrate conditions (wet, dry and re-wet). Ninety human, freshly extracted third molars were sectioned at the occlusal surface to remove enamel and to form a flat dentin wall. The specimens were restored with composite resin (Filtek Z250) and submitted to tensile bond strength testing (TBS) in an MTS 810. The data were submitted to two-way ANOVA and Tukey's test (p = 0.05). Wet dentin presented the highest TBS values for SB and CSEB. Dry dentin and re-wet produced significantly lower TBS values when using SB. OUBF was not affected by the different conditions of the dentin substrate, producing similar TBS values regardless of the surface pretreatments.
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The purpose of the work is to evaluate the stability by dry and humid of theaggregate in different systems or the use and management in Argissolos: agricultural, pasture and torest utilization. This work was realized in agricultural property, in Anhumas city, SR Several analyses including percentage of the aggregate (by way of dry and humid); the weighted mean diameter of the aggregate calculation and statistic analysis. Conclusion: the organic matter content of the A horizon of the soil under forest is 64 % more than the soil under pasture and 79 % more than the soil under annual crop; the WMDA of the aggregate obtained by dry and humid ways of the horizon A and its mean value for the soil decrease in the following sequence: PVAd - forest > PVe -pasture > PVd - annual culture, respectively, with the following values: 1.33560 and 1.445496 (D), 2.81114 and 2.351380 (H); 0.66748 and 1.011830 (D); 2.79642 and 1.624250 (H); 0.32468 and 0.993775 (S), 1.25808 and 0.983135 mm (H); the two methods are equally sensitive to reveal the effect of the soil use and management; the organic matter provides additional stability to the aggregates submitted to humid sieving and clay to the dry sieving: the WMDA obtained by dry and humid ways are statistically different for the soil profiles.
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This paper presents the results from lineal trend surface analysis technique application. The purpose was to detect positive and negative anomalies in the rain measure distribution obtained by the meteorological radar Doppler, band S, located in Bauru, during the period of 21 of October/2004 to 29 of April/2005 in the areas of Assis and Piracicaba. Using three Z-R radar relations for rain quantification was chosen the specific equation Z = 32R1,65, as the best one. The results showed that the applied methodology was able to indicate the space distribution of the rain accumulated, identifying and locating the regions where there was rainy excess and rainy lack during each analyzed period. Such results indicate areas with larger pluvial impact and consequently more favorable for environmental damages.
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The effect of phosphorus levels on seedling growth, dry and fresh matter production, and in vivo acid phosphatase activity was studied in Lychnophora ericoides cultivated during 130 days after transplanting in a greenhouse. Experimental design was completely randomized, with four P 2O 5 levels (0; 40; 80; 160 mg dm -3 as triple superphosphate) and five replicates of four plants each. The used soil was dystrophic acid dark red latosol. Lychnophora ericoides is responsive to phosphate fertilization with modification in daily relative growth rate, dry matter production and distribution among the plant parts. Acid phosphatase activity had significant and negative correlation with total, leaf and stem dry matter production, as well as with P levels accumulated in the leaf tissue. On the other hand, acid phosphatase activity had significant and positive correlation with root/shoot ratio.
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This study subjected two self-adhesive resin cements and two conventional resin cements to dry and aging conditions, to compare their microtensile bond strengths (MTBS) to dentin. Using four different luting systems (n = 10), 40 composite resin blocks (each 5x5x4 mm) were cemented to flat human crown dentin surfaces. The specimens were stored in water for 24 hours (37°C), at which point each specimen was sectioned along two axes to obtain beams that were divided randomly into two groups: dry samples, which were tested immediately, and samples that were subjected to accelerated aging conditions (12, 000 thermocycles followed by storage for 150 days). The μTBS results were affected significantly by the luting system used (P < 40001). Only the μTBS of Rely-X Unicem was reduced significantly after aging; the μTBS remained stable or increased for the other self-adhesive resin cement and the two conventional cements.
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This study compared the bond strength durability of a feldspathic veneering ceramic to glass-infiltrated reinforced ceramics in dry and aged conditions. Disc shaped (thickness: 4 mm, diameter: 4 mm) of glass-infiltrated alumina (In-Ceram Alumina) and glass-infiltrated alumina reinforced by zirconia (In-Ceram Zirconia) core ceramic specimens (N=48, N=12 per groups) were constructed according to the manufacturers' recommendations. Veneering ceramic (VITA VM7) was fired onto the core ceramics using a mold. The core-veneering ceramic assemblies were randomly divided into two conditions and tested either immediately after specimen preparation (Dry) or following 30000 thermocycling (5-55 oC±1; dwell time: 30 seconds). Shear bond strength test was performed in a universal testing machine (cross-head speed: 1 mm/min). Failure modes were analyzed using optical microscope (x20). The bond strength data (MPa) were analyzed using ANOVA (α=0.05). Thermocycling did not decrease the bond strength results for both In-Ceram Alumina (30.6±8.2 MPa; P=0.2053) and In-Ceram zirconia (32.6±9 MPa; P=0.3987) core ceramic-feldspathic veneering ceramic combinations when compared to non-aged conditions (28.1±6.4 MPa, 29.7±7.3 MPa, respectively). There were also no significant differences between adhesion of the veneering ceramic to either In-Ceram Alumina or In-Ceram Zirconia ceramics (P=0.3289). Failure types were predominantly a mixture of adhesive failure between the veneering and the core ceramic together with cohesive fracture of the veneering ceramic. Long-term thermocycling aging conditions did not impair the adhesion of the veneering ceramic to the glass-infiltrated alumina core ceramics tested.
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This research work aimed to determine the total period of interference of weeds prevention of lettuce cultivar Solaris. The experiment was conducted in Universidade Estadual de Londrina, in the period of autumn/ winter of 2008. The lettuce crop remained free from weed interference from emergence up to 0, 10, 20, 30, 40, 50 e 60 days. The experiment was arranged in a randomized block design with four replications. The weed community was composed by Bidens pilosa, Amaranthus hybridus, Oxalis corniculata, Euphorbia heterophylla, Spinacia oleracea, Commelina benghalensis e Lepidium virginicum. It was determined dry and fresh matter of weeds, and number of lettuce leaves. Assuming a tolerance of 5% for crop production decrease, it was verified that the total period of interference prevention (TPIP) occurred up to 21 days after transplanting. Weed interference throughout the crop cycle reduced 25% of its yield.
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The study was conducted to identify, through assessments of tillering, appropriate management strategies for Brachiaria decumbens cv. Basilisk under continuous stocking with cattle. Two management strategies were studied: pasture with 25 cm throughout the experimental period, and pasture with 15 cm in winter and 25 cm in spring and summer. A split-plot and randomized block design with four replications were adopted. The management strategies represented the primary factor, and the seasons (winter, spring and summer) were the secondary factor. The lowest balance between rates of appearance (TAR) and mortality (TMR) of tillers and the lowest number of vegetative tillers occurred in winter. In spring and summer, the balance and number of vegetative tillers were higher and did not differ. The lowering of pasture in winter resulted in greater balance between TAR and TMR and higher number of tillers in relation to management on sward fixed at 25 cm. There were greater numbers of reproductive and dead tillers in summer and winter, respectively. The pastures with fixed height of 25 cm contained a higher number of dead tiller. Under continuous stocking, the lowering of B. decumbens pasture in winter and its increase to 25 cm in spring and summer optimizes turnover of tillers.
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As the psychrometric method is considered standard for the measurement of relative humidity, many studies have used aspirated thermocouple psychrometers connected to microloggers but, however, they do not detail how the aspiration of the air stream is done. However, one of the major difficulties of aspirated thermocouple psychrometers is to program and to connect it in micrologger, because specific programming and connection are requires, and still some skills in getting accurate measurements. This work aimed to provide the programming and the connection of the aspirated thermocouple psychrometer type T for the CR10X microloggers and CR23X of Campbell Scientific, evaluating the quality of measurements of temperature and air relative humidity in relation the a sensor Vaisala HMP50. The non-continuous measurements were made in the period 2006/09/04 to 2007/07/11 at Jaboticabal, SP. The air temperature measurements were similar between the Vaisala sensors and aspirated thermocouple psychrometer, but the relative humidity measurements were significantly different. The measurements obtained by the aspirated thermocouple psychrometer connected to CR10X micrologger were the most accurate. Using the programming and connection of a micro-fan to suck in the dry and moist bulbs of aspirated thermocouple psychrometer in microloggers models CR10X and CR23X, it is possible to obtain measurements of air temperature with good precision and accuracy, and measurements of air relative humidity with good precision, but accuracy is not always attainable due to the difficulties inherent to the physical processes that occur in the wet bulb, the skill in the use and maintenance of this equipment and the reservoir protection against radiative effects.
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In coffee (Coffea arabica)-producing areas, particularly in the southeastern region of Brazil, it is part of the agricultural practice to incorporate coffee fruit peels in organic substrates for the production of vegetables, fruit trees, and even in the coffee cultures, for use not only as an organic amendment but also as a way to control weeds. This study aimed to evaluate the allelopathic potential of dry and fresh coffee fruit peel extracts. Therefore, lettuce, Malaysian cabbage and beggar's tick seeds and seedlings were used as test subjects for the pre-emergence, post-emergence, and mitotic index of meristematic root cell tests. Additionally, the extracts' contents of phenols, flavonoids and caffeine, in addition to their antioxidant activity, were determined. The development of all the tested seedlings was inferred by the extracts from their roots and hypocotyls. The mitotic index was reduced in comparison to the negative control. A considerable quantity of phenols, flavonoids and caffeine was found in both of the extracts. A progressively growing antioxidant activity of the extracts was observed as their concentrations increased. Through the results obtained in this study, it is possible to conclude that C. arabica has allelopathic compounds. © 2013 Elsevier B.V.