Postharvest Conservation of Mature-Green and Ripe 'Paluma' Guava Stored at Two Temperatures

This work aimed to establish the importance of maturation and ripeness stages and the use of refrigeration for the conservation of 'Paluma' guavas. Fruit picked at the mature-green and ripe stages were stored at ambient conditions (21 degrees C and 85% RH) and also at 10 degrees C (85% RH). The fruit were evaluated every 2 or 3 days for weight loss, appearance, decay, color, firmness, soluble solids, titratable acidity, ascorbic acid, total polyphenols extractable content and total antioxidant activity. The fruit stored at 21 degrees C had higher weight loss than those stored at 10 degrees C. Mature-green guavas at 21 degrees C remained in good quality for 6 days, but at 10 degrees C, the preservation period increased to 15 days. Ripe fruit were preserved for 4 days at 21 degrees C, which was extended with refrigeration to 6 days. Mature-green fruit at 21 degrees C had decay in 6 days; while at 10 degrees C decay happened in 18 days. The peel color of mature-green fruits, at 21 degrees C, showed increasing values of luminosity, indicating that its color became lighter (change from green to yellow) and at 10 degrees C it showed constant values until the end of storage. Pulp firmness of mature-green fruit declined during storage as a result of ripening. In ripe fruits such reduction occurred more slowly, since they were softer. The color of the pulp became intense red for mature fruits. Soluble solids were lower in ripe fruit at 21 degrees C, while in mature fruits at 10 degrees C, it increased. The titratable acidity increased in fruits stored at 10 degrees C. The fruits kept at 21 degrees C and the mature guavas kept at 10 degrees C showed no changes in ascorbic acid content. The ripe fruit at 10 degrees C maintained their ascorbic acid levels. Mature guavas, stored at 10 degrees C, had the longest shelf life and higher contents of soluble solids and titratable acidity, with no changes in total polyphenols extractable content and total antioxidant activity.

Performance of layers submitted to different forced-molting methods and different temperatures

This study was carried out to evaluate the performance and egg quality of laying hens, in their second laying cycle submitted to different forced-molting methods and three environmental temperatures. Six hundred layers were distributed in a completely randomized experimental design with 15 treatments with five replicates of eight birds each, according to 5x3 factorial arrangement (molting methods vs. temperatures). The following forced-molting methods were applied: 90%, 70%, 50% dietary alfalfa inclusion, addition of 2,800 ppm zinc, and feed fasting. Temperatures were: 20 ºC, 27 ºC and 35 ºC. At the end of each period of the second laying cycle, bird performance and egg quality were evaluated. Data were submitted to analysis of variance and means were compared by orthogonal and polynomial contrasts. The highest alfalfa inclusion level (90% alfalfa and 10% basal diet) proved to be efficient as compared to the other methods, independently of temperature.

Humoral immune response of broilers fed diets containing yeast extract and prebiotics in the prestarter phase and raised at different temperatures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Continuous ethanol production in a nonconventional five-stage system operating with yeast cell recycling at elevated temperatures

Three ranges of increasing temperatures (35-43, 37-45, 39-47degreesC) were sequentially applied to a five-stage system continuously operated with cell recycling so that differences of 2degreesC (between one reactor to the next) and 8degreesC (between the first reactor at the highest temperature and the fifth at the lowest temperature) were kept among the reactors for each temperature range. The entire system was fed through the first reactor. The lowest values of biomass and viability were obtained for reactor R-3 located in the middle of the system. The highest yield of biomass was obtained in the effluent when the system was operated at 35-43degreesC. This nonconventional system was set up to simulate the local fluctuations in temperature and nutrient concentrations that occur in different regions of the medium in an industrial bioreactor for fuel ethanol production mainly in tropical climates. Minimized cell death and continuous sugar utilization were observed at temperatures normally considered too high for Saccharomyces cerevisiae fermentations.

Influence of Tungsten Dopant on Sintering and Curie Temperatures of Ba(Zr0.10Ti0.90)O-3 Ceramics

Ba(Zr0.10Ti0.90)O3 (BZT10) and W+ 6 substituted BZT ceramics (BZT10:W) were prepared by mixed oxide method. The effect of W+ 6 addition in the BZT was evaluated by X-ray diffraction (XRD), dilatometer analysis, microstructural and dielectrical properties. When tungsten is introduced in the BZT lattice, a decrease in the grain size and shift on Curie temperature to lower value besides broadening of dielectric permittivity is evident. This is due repulsion between tungsten and their nearest neighbors leading to a structure which is tetragonal distorted. The sintering temperature is reduced when tungsten is introduced in the BZT lattice.

Petrologia dos granitóides brasilianos associados à zona de cisalhamento Remígio-Pocinhos(PB)

The Brasiliano Cycle in the Seridó Belt (NE Brazil) is regarded mostly as a crustal reworking event, characterized by transcurrent or transpressional shear zones which operated under high temperature and low pressure conditions. In the eastern domain of this belt- the so-called São José de Campestre Massif (SJCM), a transtensional deformation regime is evidenced by extensional components or structures associated to the strikeslip shear zones. The emplacement of the Neoproterozoic Brasiliano granitoids is strongly controled by these discontinuities. Located in the southern border of the SJCM, the Remígio-Pocinhos shear zone (RPSZ) displays, in its northern half, top to the SW extensional movement which progressively grade, towards its southern half, to a dextral strike-slip kinematics, defining a negative semi-flower structure. This shear zone is overprinted upon allocthonous metasediments of the Seridó Group and an older gneiss-migmatite complex, both of which containing metamorphic parageneses from high amphibolite to granulite facies (the latter restricted to the strike-slip zone), defining the peak conditions of deformation. Several granitoid plutons are found along this structure, emplaced coeval with the shearing event. Individually, such bodies do not exceed 30 km2 in outcropping area and are essentially parallel to the trend of the shear zone. Petrographic, textural and geochemical data allow to recognize five different granitoid suites along the RPSZ: porphyritic granites (Serra da Boa Vista and Jandaíra), alkaline granites (Serra do Algodão and Serra do Boqueirão) and medium to coarse-grained granites (Olivedos) as major plutons, while microgranite and aluminous leucogranite sheets occur as minor intrusions. The porphyritic granites are surrounded by metasediments and present sigmoidal or en cornue shapes parallel to the trend of the RPSZ, corroborating the dextral kinematics. Basic to intermediate igneous enclaves are commonly associated to these bodies, frequently displaying mingling textures with the host granitoids. Compositionally these plutons are made up by titanite-biotite monzogranites bearing amphibole and magnetite; they are peraluminous and show affinities to the monzonitic, subalkaline series. Peraluminous, ilmenite-bearing biotite monzogranites and titanite-biotite monzogranites correspond, respectivally, to the Olivedos pluton and the microgranites. The Olivedos body is hosted by metasediments, while the microgranites intrude the gneiss-migmatite complex. Being highly evolved rocks, samples from these granites plot in the crustal melt fields in discrimination diagrams. Nevertheless, their subtle alignment also looks consistent with a monzonitic, subalkaline affinity. These chemical parameters make them closer to the I-type granites. Alkaline, clearly syntectonic granites are also recognized along the RPSZ. The Serra do Algodão and Serra do Boqueirão bodies display elongated shapes parallel to the mylonite belt which runs between the northern, extensional domain and the southern strike-slip zone. The Serra do Algodão pluton shows a characteristic isoclinal fold shape structure. Compositionally they encompass aegirine-augite alkali-feldspar granites and quartz-bearing alkaline syenite bearing garnet (andradite) and magnetite plus ilmenite as opaque phases. These rocks vary from meta to peraluminous, being correlated to the A-type granites. Aluminous leucogranites bearing biotite + muscovite ± sillimanite ± garnet (S-type granites) are frequent but not volumetrically important along the RPSZ. These sheet-like bodies may be folded or boudinaged, representing partial melts extracted from the metasediments during the shear zone development. Whole-rock Rb-Sr isotope studies point to a minimum 554��10 Ma age for the crystalization of the porphyritic granites. The alkaline granites and the Olivedos granite produced ca. 530 Ma isochrons which look too young; such values probably represent the closure of the Rb-Sr radiometric clock after crystallization and deformation of the plutons, at least 575 Ma ago (Souza et al. 1998). The porphyritic and the alkaline granites crystallized under high oxygen fugacity conditions, as shown by the presence of both magnetite and hematite in these rocks. The presence of ilmenite in the Olivedos pluton suggests less oxidizing conditions. Amphibole and amphibole-plagioclase thermobarometers point to minimum conditions, around 750°C and 6 Kbars, for the crystallization of the porphyritic granites. The zirconium geothermometer indicates higher temperatures, in the order of 800°C, for the porphyritic granites, and 780°C for the Olivedos pluton. Such values agree with the thermobarometric data optained for the country rocks (5,7 Kbar and 765°C; Souza et al. 1998). The geochemical and isotope data set point to a lower crustal source for the porphyritic and the alkaline granites. Granulite facies quartz diorite to tonalite gneisses, belonging or akin to the gneiss-migmatite complex, probably dominate in the source regions. In the case of the alkaline rocks, subordinate contributions of mantle material may be present either as a mixing magma or as a previously added component to the source region. Tonalite to granodiorite gneisses, with some metasedimentary contribution, may be envisaged for the Olivedos granite. The diversity of granitoid rocks along the RPSZ is explained by its lithospheric dimension, allowing magma extraction at different levels, from the middle to lower crust down to the mantle. The presence of basic to intermediate enclaves, associated to the porphyritic granites, confirm the participation of mantle components in the magma extraction system along the RPSZ. This mega-structure is part of the network of Brasiliano-age shear zones, activated by continental collision and terrane welding processes at the end of the Neoproterozoic

Pirometamorfismo nos arenitos da Formação Açu, Bacia Potiguar, NE do Brasil

Pyrometamorphism results from conditions of high temperatures and very low pressures provoked by the intrusion of hypabyssal basic bodies into sedimentary or metassedimentary hosting rocks. The onshore portion of the Potiguar Basin in NE Brazil offers examples of this type of metamorphism nearby the contacts of Paleogene to Neogene plugs, sills and dikes of diabases and basalts crosscutting sandstones, siltstones and shales of the Açu Formation (Albian-Cenomanian). The thermal effects over these rocks are reflected on textures and minerals assemblages that characterize the sanidinite facies of metamorphism, often with partial melting of the feldspathic and mica-rich matrix. The liquid formed is potassic and peraluminous, with variably colored rhyolitic glass (colorless, yellow, brown) comprising microcrystals of tridymite, sanidine and clinoenstatite, besides residual detrital clasts of quartz and rarely zircon, staurolite and garnet. Lenses of shale intercalated within the sandstones display crystallites of Fe-cordierite (sekaninaite), mullite, sanidine, armalcolite (Fe-Ti oxide) and brown spinel. The rocks formed due to the thermal effect of the intrusions are called buchites for which two types are herein described: a light one derived from feldspathic sandstone and siltstone protoliths; and a dark one derived from black shale protoliths. Textures indicating partial melting and minerals such as sanidine, mullite, tridymite and armalcolite strongly demonstrate that during the intrusion of the basic bodies the temperature reached 1,000-1,150°C, and was followed by quenching. Cooling of the interstitial melts has as consequences the closure of pores and decrease of the permeability of the protolith, which varies from about 17-11% in the unaffected rocks to zero in the thermally modified types. Although observed only at contacts and over small distances, the number of basic intrusions hosted within the Potiguar Basin in both onshore and offshore portions leaves opened the possibility of important implications of the thermal effects over the hydrocarbon exploration in this area as well in other Cretaceous and Paleozoic basins in Brazil

Importance of sperm genotype (indicus versus taurus) for fertility and embryonic development at elevated temperatures

Heat stress has negative effects on bovine reproduction, particularly for European breeds (Bos taurus taurus) that are less thermotolerant than zebu cattle (Bos taurus indicus). Here, the evidence that spermatozoa and oocyte both contribute to early embryonic resistance to heat shock is demonstrated. In addition, the use of reproductive biotechnologies to improve bovine thermotolerance, are outlined by comparing data from taurus, indicus and crossbred genotypes. (c) 2005 Published by Elsevier B.V.

Digestibility of feeds containing sorghum, with and without tannin, for broiler chickens submitted to three room temperatures

The traditional method of total excreta collection was applied, using 30 to 40 day old male Ross 308 broiler chickens. One hundred and eight broiler chickens were used, randomly assigned to a 3x3 factorial experimental design. The room temperatures were 14 C (cold), 25 °C (thermoneutral) and 32 °C (hot) and the three diets were 100% maize, 100% sorghum with tannin and 100% sorghum without tannin, with four replicates of each. The digestibility coefficients for the dry matter, crude protein, crude fibre, neutral detergent fibre, acid detergent fibre, ether extract, mineral matter and nitrogen-free extract were determined. It was observed that all the digestibility coefficients were higher in the hot chamber and lower in the cold chamber, and that these values tended to be higher for maize.

Effects of dietary trace mineral sources and levels fed to layers in their second laying cycle on the quality of eggs stored at different temperatures and for different periods

This study aimed at evaluating the effects of trace mineral levels and sources supplemented to diets fed to semi-heavy layers in their second laying cycle on the quality of eggs stored for 14 days at different temperatures. The experimental diets consisted of the inclusion of inorganic trace minerals (T1 - control: 100% ITM) and five supplementation levels of organic trace minerals (carboaminophopho chelates) (110, 100, 90, 80, and 70% OTM). Trace mineral inclusion levels (mg/kg feed) were: T1: control - 100% ITM: Zn (54), Fe (54), Mn (72), Cu (10), I (0.61) Se (0.3); T2 - 110% OTM: Zn (59.4), Fe (59.4), Mn (79.2), Cu (11.88), I (1.21) Se (0.59); T3 - 100%: OTM: Zn (54), Fe (54), Mn (72), Cu (10.8), I (1.10) Se (0.54); T4 - 90% OTM: Zn (48.6), Fe (48.6), Mn (64.8), Cu (9.72), I (0.99) Se (0.49); T5 - 80% OTM: Zn (43.2), Fe (43.2), Mn (57.6), Cu (8.64), I (0.88), Se (0.43); T6 - 70% OTM: Zn (37.8), Fe (37.8), Mn (50.4), Cu (7.56), I (0.77) Se (0.38). A completely randomized experimental design in a split-plot arrangement with 60 treatments of four replicates each was applied. The combination of six diets versus storage temperature (room or under refrigeration) was randomized in plots, whereas the sub-plots consisted of storage times (0, 3, 7, 10, and 14 days). Data were submitted to analysis of variance of a model in slip-plots in time using the software package SAS (2000) at 5% probability level. It was concluded that 70% OTM supplementation can be used with no damage to egg quality, independently from storage temperature or time. The quality of refrigerated eggs stored up to 14 days is better than those stored at room temperature.

Ectopic mineralization of articular cartilage in the bullfrog Rana catesbeiana and its possible involvement in bone closure

Mineralization of the articular cartilage is a pathological condition associated with age and certain joint diseases in humans and other mammals. In this work, we describe a physiological process of articular cartilage mineralization in bullfrogs. Articular cartilage of the proximal and distal ends of the femur and of the proximal end of the tibia-fibula was studied in animals of different ages. Mineralization of the articular cartilage was detected in animals at 1 month post-transformation. This mineralization, which appeared before the hypertrophic cartilage showed any calcium deposition, began at a restricted site in the lateral expansion of the cartilage and then progressed to other areas of the epiphyseal cartilage. Mineralized structures were identified by von Kossa's staining and by in vivo incorporation of calcein green. Element analysis showed that calcium crystals consisted of poorly crystalline hydroxyapatite. Mineralized matrix was initially spherical structures that generally coalesced after a certain size to occupy larger areas of the cartilage. Alkaline phosphatase activity was detected at the plasma membrane of nearby chondrocytes and in extracellular matrix. Apoptosis was detected by the TUNEL (TDT-mediated dUTP-biotin nick end-labeling) reaction in some articular chondrocytes from mineralized areas. The area occupied by calcium crystals increased significantly in older animals, especially in areas under compression. Ultrastructural analyses showed clusters of needle-like crystals in the extracellular matrix around the chondrocytes and large blocks of mineralized matrix. In 4-year-old animals, some lamellar bone (containing bone marrow) occurred in the same area as articular cartilage mineralization. These results show that the articular cartilage of R. catesbeiana undergoes precocious and progressive mineralization that is apparently stimulated by compressive forces. We suggest that this mineralization is involved in the closure of bone extremities, since mineralization appears to precede the formation of a rudimentary secondary center of ossification in older animals.

Population dynamics of Musca domestica (Diptera: Muscidae): experimental and theoretical studies at different temperatures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Shikimate Kinase (EC 2.7.1.71) from Mycobacterium tuberculosis: Kinetics and Structural Dynamics of a Potential Molecular Target for Drug Development

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Population dynamics of Chrysomya megacephala (Diptera : Calliphoridae) at different temperatures

In this study we analysed the theoretical population dynamics of C. megacephala, an exotic blowfly, kept at 25 and 30degreesC, using a density-dependent mathematical model, with parametric estimates of survival and fecundity in the laboratory. No change in terms of oscillation patterns was found for the two temperatures. The populations exhibited a two-point limit cycle, i.e. oscillations between two fixed points, at 25 and 30degreesC. However a quantitative change was observed, indicating that at 25degreesC the number of immatures in equilibrium is 1176 and at 30degreesC, 1944. The implications of this difference in terms of equilibrium for population dynamics of C. megacephala are discussed.

The Influence of Solutes on the Enthalpy/Entropy Change of the Actinomycin D Binding to DNA: Hydration, Energy Compensation and Long-Range Deformation on DNA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)