Energy and oil levels in broiler starter diets

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

Optical studies of the correlation between interface disorder and the photoluminescence line shape in GaAs/InGaP quantum wells

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

Amniocentesis and biochemical evaluation of amniotic fluid in ewes at 70, 100 and 145 days of pregnancy

The objectives of this study were to determine the technical viability of amniocentesis in sheep and to observe biochemical changes in the amniotic fluid components. Amniotic fluid samples were collected by puncture in the greatest curvature of the uterine hum at days 70, 100, and 145 of pregnancy. The surgical procedure for collection of amniotic fluid samples was safe and efficient. For three stages of pregnancy, the following results were obtained: pH values 8.36, 7.34 and 7.37; glucose concentrations, 16.06. 8.58, and 3.79 g/dl; urea values, 42.68, 33.53, and 25.49 mg/dl; creatinine, 0.85, 5.04, and 11.25 g/dl; Gama-GT enzyme, 12.58, 14.20, and 12.30 UI/l; sodium concentrations, 146.60, 129.42, and 103.8 mmol/l: potassium concentrations, 9.79, 6.15, and 8.65 mmol/l; chloride, 96.59, 85.28, and 65.35 mmol/l; total protein, 0.14, 0.23, and 0.24 g/dl, respectively. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Bond strength of resin modified glass ionomer cement to primary dentin after cutting with different bur types and dentin conditioning

The aim of this in vitro study was to evaluate the effect of different bur types and acid etching protocols on the shear bond strength (SBS) of a resin modified glass ionomer cement (RM-GIC) to primary dentin. Forty-eight clinically sound human primary molars were selected and randomly assigned to four groups (n=12). In G1, the lingual surface of the teeth was cut with a carbide bur until a 2.0-mm-diameter dentin area was exposed, followed by the application of RM-GIC (Vitremer - 3M/ESPE) prepared according to the manufacturer's instructions. The specimens of G2, received the same treatment of G1, however the dentin was conditioned with phosphoric acid. In groups G3 and G4 the same procedures of G1 and G2 were conducted respectively, nevertheless dentin cutting was made with a diamond bur. The specimens were stored in distilled water at 37 degrees C for 24h, and then tested in a universal testing machine. SBS. data were submitted to 2-way ANOVA (= 5%) and indicated that SBS values of RM-GIC bonded to primary dentin cut with different burs were not statistically different, but the specimens that were conditioned with phosphoric acid presented SBS values significantly higher that those without conditioning. To observe micromorphologic characteristics of the effects of dentin surface cut by diamond or carbide rotary instruments and conditioners treatment, some specimens were examined by scanning electron microscopy. Smear layer was present in all specimens regardless of the type of rotary instrument used for dentin cutting, and specimens etched with phosphoric acid presented more effective removal of smear layer. It was concluded that SBS of a RM-GIC to primary dentin was affected by the acid conditioning but the bur type had no influence.

Psychophysical power functions for estimates of area: Effects of age and educational levels

The purpose of the present study was to verify the memory exponents of power function for area in observers of different age and educational levels (elementary school, high school or undergraduate school), using the psychophysics method of magnitude estimation. For the age level I (17 to 30 years old) there was no difference among educational levels, although for the age level II (45 to 60 years old) the differences were significant. Tn the age level II, there was a tendency for greater variability of the responses for lower educational levels. The data obtained for the age level I did not show the same results, although a significant difference among the three educational levels was observed. We call conclude that the mnemonic processes present different results when we observe the answers from observers with different ages. This result leads us to suppose that the motivational factor related to the stimulus used can interact with the mnemonic processes.

Grazing incidence X-ray diffraction and atomic force microscopy analysis of BaBi2Ta2O9 thin films

Thin films of BaBi2Ta2O9 (BBT) composition were prepared through the metal organic decomposition method. The crystallinity, phase formation, crystallite size and morphology of the thin films were measured as a function of the type of substrate, stoichiometry of solution and process variables such as thickness and temperature. The thin films were investigated by grazing incidence X-ray diffractometry and atomic force microscopy (AFM) techniques. For the sample without excess of bismuth, diffraction peaks other than that of the BBT phase were observed. A well crystallized BBT single phase was observed for films prepared from a solution with 10% excess of bismuth, deposited on Si/Pt substrate, with a thickness up to 150 nm and sintered at temperatures of 700 degreesC. The thin BBT phase films heat-treated at 600 degreesC presented a diffraction pattern characteristic of samples with lower degree of crystallinity whereas for the thin films heat-treated at 800 degreesC, we observed the presence of other phases than the BBT. For the thin film deposited on the Sin+ substrate, we observe that the peaks corresponding to the BBT phase are broader than that observed on the samples deposited on the Pt and Si/Pt substrates. No variation of average crystallite size was observed as the excess of Bi increased from 10 to 20%. AFM images for the samples showed that the increasing the amount of bismuth promotes grain growth. The average surface roughness measured was in the range of 16-22 nm showing that the bismuth amount had no or little effect on the roughness of films. (C) 2002 Elsevier B.V. B.V. All rights reserved.

DIFFRACTION AND THE GLUON MASS

We recently proposed a QCD Pomeron described by the exchange of two nonperturbative gluons characterized by a dynamically generated gluon mass. It is shown here that data on elastic scattering, exclusive rho production in deep inelastic scattering, and the J/psi-nucleon total cross section can be successfully described in terms of a single gluon mass m(g) congruent-to 0.37 GeV. We observe that the total cross sections of hadrons with small radii, such as J/psi, have a marked dependence on the effective gluon mass.

Influence of different dentin etching times and concentrations and air-abrasion technique on dentin microtensile bond strength

Purpose: To determine the influence of different dentin treatments on the microtensile bond strengths of adhesive resins to dentin. Methods: Fifteen human molars were ground to 600-grit to obtain flat root-dentin surfaces. Five different dentin treatments were evaluated: Group 1 - 10% phosphoric acid for 30 seconds; Group 2 - 37% phosphoric acid for 15 seconds; Group 3 - air-abrasion for 10 seconds followed by 10% phosphoric acid for 30 seconds; Group 4 - air-abasion for 10 seconds followed by 37% phosphoric acid for 15 seconds. The dental adhesive (OptiBond Solo Plus) was applied according to manufacturer's instructions and followed by composite (Z100) application to provide sufficient bulk for microtensile bond testing. All samples were placed in distilled water for 24 hours at 37degreesC, thermocycled for 500 cycles in distilled water at 10degreesC and 50degreesC, and serially sliced perpendicular to the adhesive surface and subjected to tensile forces (0.5 mm/minute). Additional samples were prepared for SEM to observe the adhesive interface. Results: Group 2 exhibited significantly (P< 0.05) lower bond strength values than all other treatments. The bond strengths of the different conditions were (in MPa): Group 1: 43.0 +/- 16.1; Group 2: 29.2 +/- 8.3; Group 3: 48.1 +/- 14.2; Group 4: 41.0 +/- 9.3. The dentin treated with phosphoric acid 37% for 15 seconds showed the lowest values of microtensile bond strength. The results obtained with Groups 1, 3 and 4 were statistically similar.

Evaluation of survival of Staphylococcus aureus and Clostridium botulinum in charqui meats

Charqui meats were prepared in laboratory conditions in order to carry out experiments to observe the possibility of development of enterotoxigenic Staphylococcus aureus and Clostridium bottilinum proteolytic type B spores and their toxins. Results demonstrated that the harsh processing conditions, high salt concentration, relative high temperature, a, values, inhibited the growth of both bacteria. Under our experimental conditions, S. aureus would survive throughout the sequence of salting steps i.e. brine followed by rock salting and the sunshine drying step. However, at final a(w) value of 0.70-0.75 would create conditions to inhibit its development. The other experiment revealed that C. botulinum spores germination also was impaired because of these low a(w) values. Under these conditions, charqui meats revealed to be safe products in relation to toxins from both enterotoxigenic S. aureus and C. botulinum. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

Simultaneous observation of collagen and elastin in normal and pathological tissues: analysis of Sirius-red-stained sections by fluorescence microscopy

In order to observe collagen and elastic fibers simultaneously, sections of human aorta, skin, lung, liver, and bladder were stained by Sirius red and analyzed by fluorescence microscopy. In all cases, the fibers of collagen presented the characteristic fluorescent red-orange color that results from the interaction of this extracellular protein with the dye, whereas elastic fibers showed strong green fluorescence (intrinsic fluorescence). This method efficiently detects collagen and elastic fibers when these two structures are present and could have valuable applications in processes that involves both fibers.

Towards an insight on the photoluminescence of disordered CaWO4 from a joint experimental and theoretical analysis

A joint experimental and theoretical study has been carried out to rationalize for the first time the photoluminescence (PL) properties of disordered CaWO4 (CWO) thin films. From the experimental side, thin films of CWO have been synthesized following a soft chemical processing, their structure has been confirmed by X-ray diffraction data and corresponding PL properties have been measured using the 488 nm line of an argon ion laser. Although we observe PL at room temperature for the crystalline thin films, the structurally disordered samples present much more intense emission. From the theoretical side, first principles quantum mechanical calculations, based on density functional theory at B3LYP level, have been employed to study the electronic structure of a crystalline (CWO-c) and asymmetric (CWO-a) periodic model. Electronic properties are analyzed in the light of the experimental results and their relevance in relation to the PL behavior of CWO is discussed. The symmetry breaking process on going from CWO-c to CWO-a creates localized electronic levels above the valence band and a negative charge transfer process takes place from threefold, WO3, to fourfold, WO4,. tungsten coordinations. The correlation of both effects seems to be responsible for the PL of amorphous CWO. (c) 2005 Elsevier B.V. All rights reserved.

Combined TUNEL and TRAP methods suggest that apoptotic bone cells are inside vacuoles of alveolar bone osteoclasts in young rats

Although it is generally accepted that osteoclasts breakdown and resorb bone matrix, the possibility that they may also be able to engulf apoptotic osteoblasts/ lining cells and/or osteocytes remains controversial. Apoptosis of osteoblasts/ lining cells and/or osteocytes and interactions between these cells and osteoclasts are extremely rapid events that are difficult to observe in viva. A suitable in viva model for studying these events is the alveolar bone of young rats because it is continuously. Thus, sections of aldehyde fixed alveolar undergoing intense resorption/remodeling bone of young rats were stained by the combined terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method and the tartrate-resistant acid phosphatase (TRAP) method for the simultaneous visualization of apoptotic cells and osteoclasts in the same section. The combined TUNEL and TRAP reactions, in the same section, greatly facilitated visualization of relationship between osteoclasts and apoptotic bone cells during alveolar bone remodeling. Our results showed that several TRAP-positive osteoclasts exhibited large vacuoles containing TUNEL positive apoptotic structures, probably derived from osteoblasts/lining cells and/or osteocytes. These results support the idea that alveolar bone osteoclasts are able to internalize dying apoptotic bone cells.

Electromyographic study in Erector spinae, Rectus abdominis, Glutaeous maximus and Rectus femuris muscles, in standing and static posture with load on hands

Observe the loads associates application with in position of body, in the static or dynamic postures. Methods: the electromyographic study in erector spinae, rectus abdominis, glutaeous maximus and rectus femoris muscles was accomplished in female volunteers from 18 have 27 years old, previously selected. The muscles electric activities was gotten with surface electrodes, in standing and static posture, with the parallels and horizontal upper limbs with load on their hands. Conclusion: In this study it was clearly observed influence of the load and distance there is over studied musculature associated with standing erect posture.

Do high progesterone concentrations decrease pregnancy rates in embryo recipients synchronized with PGF2 alpha and eCG?

The objective of this study was to evaluate the effects of equine chorionic gonadotropin (eCG) treatment on the number of induced accessory corpora lutea (CL), plasma progesterone concentrations and pregnancy rate in cross-bred heifers after transfer of frozen-thawed (1.5 M ethylene glycol) embryos. All recipients received 500 mug PGF2alpha (dl-cloprostenol, i.m.) at random stages of the estrous cycle (Day 0) and were observed for estrus for 7 days. on Day 14, heifers detected in estrus between 2 and 7 days after PGF2alpha treatment were randomly allocated to four groups (n = 83 per group) and given 0 (control), 200, 400, or 600 IU of eCG. Two days later (Day 16), these recipients were given PGF2a and observed for estrus. Six to eight days after detection of estrus, plasma samples were collected to determine progesterone concentration and ultrasonography was performed to observe ovarian structures. Heifers with multiple CL or a single CL >15 mm in diameter received an embryo by direct transfer. Embryos of excellent and good quality were thawed and transferred to the recipients by the same veterinarian. Pregnancy was diagnosed by ultrasonography and confirmed by transrectal palpation 21 and 83 days after embryo transfer (ET), respectively. Plasma progesterone concentrations on the day of transfer (Day 7 of the estrous cycle) were 3.9 +/- 0.7, 4.2 +/- 0.4, 6.0 +/- 0.4, and 7.8 +/- 0.6 ng/ml for groups Control, 200, 400, and 600, respectively (Control versus treated groups P = 0.009; 200 versus 400 and 600 groups P = 0.0001; and 400 versus 600 P = 0.012). Conception rates 83 days after ET were 41.9, 50.0, 25.0, and 20.9% for groups Control, 200, 400, and 600, respectively (200 versus 400 and 600 groups P = 0.0036). In conclusion, an increase in progesterone concentration, induced by eCG treatment, did not improve pregnancy rates in ET recipients. Conversely, there was a decline in conception rates in the animals with the highest plasma progesterone concentrations. (C) 2003 Elsevier B.V. All rights reserved.

Thermodynamic models for water sorption by grape skin and pulp

The enthalpy-entropy compensation theory was applied to water sorption for grapes of Italy variety. The moisture sorption isotherms were analyzed using the static gravimetric method at 35, 40, 50, 60, 70 and 75 degrees C. For isotherms construction, the skin and pulp of the grape were used separately and it was possible to observe significant differences. The GAB equation was fitted to the experimental data, using direct nonlinear regression analysis; the agreement between experimental and calculated values was satisfactory. The net isosteric heat or enthalpy of water sorption, determined from the equilibrium sorption data, showed a different behavior when compared with other works, as it was obtained for skin and pulp separately. Plots of Delta h vs Delta S for skin and pulp provided the isokinetic temperatures T-Bs = 423.2 +/- 27.6 K and T-Bp = 424.5 +/- 25.3 K, respectively, indicating an enthalpy-controlled desorption process over the whole range of moisture content considered.