Production and body composition traits of broilers in relation to breast weight evaluated by path analysis

O peso do peito possui grande importância econômica na indústria de frangos, podendo estar associado a outras variáveis passíveis de seleção. Estimaram-se correlações fenotípicas entre características de desempenho (peso vivo aos 7, 28 dias e ao abate e profundidade de músculo peitoral por ultra-sonografia), carcaça (peso eviscerado e de pernas) e composição corporal (peso do coração, do fígado e da gordura abdominal), em uma linhagem de frangos, e quantificou-se a influência direta e indireta destas variáveis sobre o peso do peito. Para tanto, utilizou-se a análise de trilha, desdobrando-se a matriz de correlações parciais em coeficientes que forneceram a influência direta de uma variável sobre a outra, independentemente das demais. A manutenção das variáveis peso vivo ao abate e peso eviscerado na matriz de correlações pode ser prejudicial à análise estatística que envolve os sistemas de equações normais, como a análise de trilha, devido à multicolinearidade observada. O peso vivo ao abate e a profundidade do músculo peitoral por ultra-sonografia apresentaram efeitos diretos importantes sobre o peso de peito e foram identificadas como as principais responsáveis pela magnitude dos coeficientes de correlação obtidos. Assim, uma pré-seleção individual para estas características pode favorecer um aumento no peso de peito nesta linhagem, se mantidas as condições ambientais de criação dos frangos, uma vez que o peso vivo ao abate e a profundidade de músculo peitoral por ultra-sonografia afetam fenotipicamente e diretamente o peso de peito.

Nest architecture of the leaf-cutting ant Acromyrmex rugosus rugosus

The prominent nests mounds of many ant species are one of the most obvious signs of their presence, yet the subterranean architecture of nests is often poorly known. The present work aimed to establish the external and internal structure of nests of a species of leaf-cutting ant, Acromyrmex rugosus rugosus, by either marking the interior of nests with talcum powder, or forming casts with cement. Twelve nests were excavated and surveyed, with eight being marked with talcum powder and four cast with cement. The external and internal structure of the nests was highly variable. The largest and smallest nests had mound areas of 9.89 m(2) and 0.01 m(2) respectively. The number of chambers found ranged from I to 26, with maximum dimensions of between 6 and 70 cm. Chambers were found close to the soil surface (6 cm) down to a maximum depth of 3.75 m. In addition to chambers containing fungus garden, some chambers were found to be empty, filled with soil or filled with waste, the first time this has been recorded in a species of Acromyrmex. The nests of A. rugosus rugosus appear to be unusually complex for the genus, containing a diversity of irregular chambers and tunnels.

Asymmetrical penetration of microwave in a conducting media and determination of microwave conductivity for very thin samples using electron spin resonance

Dyson's theory of conduction electron spin resonance (CESR) has been used in the limit d less than or equal to delta (d being the thickness of the sample and delta the skin depth of the microwave field) to obtain the microwave conductivity from the (A/B) ratio of the CESR absorbed power derivative. In this work we calculate the CESR absorbed power derivative using Kaplan's approach and show that the (A/B) ratio can be enhanced if asymmetrical penetration of microwave is used, which means that the microwave field enters into the sample from one of the faces. Therefore, the determination of the microwave conductivity from the (A/B) ratio of the CESR line can be performed for thinner samples. Experimentally, asymmetrical penetration can be obtained if one of the sample's faces is covered with a thin gold layer. The determination of microwave conductivity in conducting polymers films is among the possible applications of this method. (C) 2001 Elsevier B.V. Ltd. All rights reserved.

Effect of the type of environmental stress on the emergence of sunflower (Helianthus annus L.), soybean (Glycine max (L.) Merril) and maize (Zea mays L.) seeds with different levels of vigor

Sowing is a critical time in the cycle of a crop and the seeds are frequently exposed to adverse conditions that may compromise the establishment of seedlings in the field. on this basis, the objective of the present study was to determine the effect of types of environmental stress on the emergence of sunflower, maize and soybean seeds with different levels of vigor. High vigor seeds were artificially aged in order to obtain medium and low vigor seeds and then they were sown in clay soil in plastic boxes and submitted to the following types of environmental stress during the germination process : 1) high temperature (35degreesC), 2) low temperature (15 or 18degreesC), 3) water excess (Psi > -0.0001 MPa), 4) water deficiency (Psi approximately equal to -1.1; -1.2 and -0.6 MPa for sunflower, maize and soybean, respectively), 5) sowing at a depth of 7 cm and 6) pathogenic infection of sunflower seeds with Alternaria helianthi, of maize seeds with Fusarium moniliforme and of soybean seeds with Colletotrichum dematium, var. truncata. The results were compared to those obtained with controls sown under optimal condition. It was concluded that: 1) the effect of seed vigor on emergence depends on the type of enviromental stress to which the seeds are exposed, 2) the stress to which the the seeds demonstrated highest sensitivity varied with species and 3) high temperature stress was the one that most impaired the emergence of the three species.

Dry matter production of shoots and root density of two cultivars of Lablab purpureus (L.) Sweet

This experiment was conducted in green house conditions to evaluate the DM accumulation in the shoots and in the roots of two cultivars of Lablab purpureus (L.) Sweet. A 2x3 factorial (two cultivars and three evaluation dates) was conducted according to a randomized complete block design with four replications, being the cultivars Highworth and Rongai evaluated at 42, 56, and 70 days after seedling emergence (DASE). The results indicated that the cvs. Highworth and Rongai have the same pattern of DM accumulation in the shoots. In the upper layer of the soil (0-0.20 in) it was found 38.83% and 43.64% of the DM accumulated in the roots down to 2.00 in depth, in the cvs. Highworth and Rongai, respectively. In the deepest layer (1.80-2.00 in) it was found 3.02% and 1.5% of the DM accumulated in the roots of the cvs. Highworth and Rongai, respectively. The root density showed a striking decrease upper layer from the soil (0-0.2 m) down to the depth of 0.60 0.80 in (from 10.83 to 1.75 cm.cm(-3) in the cv. Highworth and from 10.76 to 1.28 cm.cm(-3) in the cv. Rongai). At the bottom layer (1.80-2.00 in) the root density values were 0.98 cm.cm(-3) and 0.59 cm.cm(-3), respectively for the cvs. Highworth and Rongai. The root/shoot ratios were similar in both cvs. and decreased from 42 to 70 DASE showing that the cvs. evaluated had the same dynamics of DM accumulation.

Evaluation of the isoflurane-sparing effects of lidocaine and fentanyl during surgery in dogs

Objective-To evaluate the isoflurane-sparing effects of lidocaine and fentanyl administered by constant rate infusion (CRI) during surgery in dogs.Design-Randomized prospective study.Animals-24 female dogs undergoing unilateral mastectomy because of mammary neoplasia.Procedures-After premedication with acepromazine and morphine and anesthetic induction with ketamine and diazepam, anesthesia in dogs (n = 8/group) was maintained with isoflurane combined with either saline (0.9% NaCl) solution (control), liclocaine (1.5 mg/kg [0.68 mg/lb], IV bolus, followed by 250 mu g/kg/min [113 mu g/lb/min], CRI), or fentanyl (5 mu g/kg [2.27 mu g/lb], IV bolus, followed by 0.5 mu g/kg/min [0.23 mu g/lb/min], CRI). Positive-pressure ventilation was used to maintain eucapnia. An anesthetist unaware of treatment, endtidal isoflurane (ETiso) concentration, and vaporizer concentrations adjusted a nonprecision vaporizer to maintain surgical depth of anesthesia. Cardiopulmonary variables and ETiso values were monitored before and after beginning surgery.Results-Heart rate was lower in the fentanyl group. Mean arterial pressure did not differ among groups after surgery commenced. In the control group, mean +/- SD ETiso values ranged from 1.16 +/- 0.35% to 1.94 +/- 0.96%. Fentanyl significantly reduced isoflurane requirements during surgical stimulation by 54% to 66%, whereas the reduction in ETiso concentration (34% to 44%) observed in the lidocaine group was not significant.Conclusions and Clinical Relevance-Administration of fentanyl resulted in greater isoflurane sparing effect than did liclocaine. However, it appeared that the low heart rate induced by fentanyl may partially offset the improvement in mean arterial pressure that would be expected with reduced isoflurane requirements.

Consequences of crown fractures with pulpal exposure: histopathological evaluation in dogs

When a crown fracture involving pulpal exposure is produced, the therapeutic treatment to be applied depends to a great extent on the general histopathological condition of the exposed pulp. Hence, the objective of this study was to evaluate histopathological and bacteriological changes occurring in dental tissue and periradicular tissue of crown-fractured teeth with pulpal exposure. Twenty-four anterior teeth (central and lateral incisors) from the maxillary teeth of four young, adult Mongrel dogs were used. At 48 and 72 h after performing the crown fractures, the animals were sacrificed and the results evaluated. Both observation periods revealed the existence of an area of superficial inflammation with the formation of hyperplastic tissue towards the external surface. Intense neutrophilic infiltrate was observed below it. Mean depth of inflammation was greater at 48 h (4633.33 mum) than at 72 h (3933.33 mum), perhaps coinciding with the bigger pulp chamber opening (x1332.14 mum at 48 h vs. x479.52 mum at 72 h). Upon approaching the cervical portion, the inflammation became less. Bacterial contamination was constant in all the cases evaluated, worsening the histopathological findings with exposure time. This study demonstrates that when a crown fracture with pulpal exposure is produced, the success in treating it depends partly on how quickly therapeutic treatment is administered.

Evaluation of the influences of solution path length and additives concentrations on the solar photo-Fenton degradation of 4-chlorophenol using multivariate analysis

This study reports the photodegradation of 4-chlorophenol (4-CP) in aqueous solution by the photo-Fenton process using solar irradiation. The influence of solution path length, and Fe(NO3)(3) and H2O2 concentrations on the degradation of 4-CP is evaluated by response surface methodology. The degradation process was monitored by the removal of total organic carbon (TOC) and the release of chloride ion. The results showed a very important role of iron concentration either for TOC removal or dechlorination. on the other hand, a negative effect of increasing solution path length on mineralization was observed, which can be compensated by increasing the iron concentration. This permits an adjustment of the iron concentration according to the irradiation exposure area and path length (depth of a tank reactor). Under optimum conditions of 1.5 mM Fe(NO3)(3), 20.0 mM H2O2 and 4.5 cm solution path length, 17 min irradiation under solar light were sufficient to reduce a 72 mg C L-1 solution of 4-CP by 91 (c) 2006 Elsevier B.V. All rights reserved.

Statistical methods applied to the analysis of blasting vibrations in a diabase quarry in the city of Campinas, (SP) Brazil

Statistical methods of multiple regression analysis, trend surface analysis and principal components analysis were applied to seismographic data recorded during production blasting at a diabase quarry in the urban area of Campinas (SP), Brazil. The purpose of these analyses was to determine the influence of the following variables: distance (D), charge weight per delay (W), and scaled distance (SD) associated with properties of the rock body (orientation, frequency and angle of geological discontinuities; depth of bedrock and thickness of the soil overburden) in the variation of the peak particle velocity (PPV). This approach yielded variables with larger influences (loads) on the variation of ground vibration, as well as behavior and space tendency of this variation. The results showed a better relationship between PPV and D, with D being the most important factor in the attenuation of the ground vibrations. The geological joints and the depth to bedrock have a larger influence than the explosive charges in the variation of the vibration levels, but frequencies appear to be more influenced by the amount of soil overburden.

Effect of handpiece tip design on the cutting efficiency of an air abrasion system

Purpose : the aim of this study was to evaluate the effect of nozzle angle and tip diameter on the cutting efficiency of an air abrasion system. Materials and Methods: Thirty-six extracted human third molars were air-abraded with the PrepStar microabrasion machine using a handpiece with either 80degrees or 45degrees nozzle angles with 0.38 or 0.48 nun tip orifice diameters. The following parameters were held constant: abrasive particle size (27 mum), air pressure (80 psi), distance (2 mm.) and duration (15 seconds). The cutting efficiency was compared using enamel, dentin and cementum substrates. Width and depth of the cutting patterns were analyzed and measured using scanning electron micrographs. Results: Statistical analysis using three-way ANOVA and Duncan's Multiple Range test revealed that the width of the cuts was significantly greater when the cavities were prepared using the 45degrees nozzle angle. Significantly deeper cavities were produced with the 80degrees nozzle angle. The tip orifice of the nozzle influenced the cutting efficiency in softer substrates, dentin and cementum. Precise removal of hard tissue is best accomplished using the 80degrees angle nozzle tips for all types of tooth surfaces, enamel, dentin and cementum.

Comparison of direct digital and conventional imaging with Ekta Speed Plus and INSIGHT films for the detection of approximal caries

Purpose: To evaluate the accuracy of approximal caries detection comparing enhanced and unenhanced Sidexis CCD-based digital image with Ektaspeed Plus and INSIGHT films. Methods: Fifty-two extracted premolars were imaged under identical standardized geometric and exposure conditions. Four observers, using five points confidence scale, rated 104 approximal surfaces for the presence or absence of carious lesions by means of four image modalities: (1) observer enhanced; (2) unenhanced Sidexis displays; (3) E speed films and (4) F speed film. Histologic sections served as validating criterion for the presence and depth of carious lesions. Diagnostic accuracy was measured as the area beneath the ROC curve. Results: Mean ROC (receiver operating characteristic) curve areas for approximal surfaces were 0.865 (E speed), 0.856 (F speed), 0.816 (unenhanced Sidexis) and 0.776 (observer enhanced). There were no significant differences between unenhanced digital Sidexis and films. Observer enhanced Sidexis images exhibited a statistically significant lower diagnostic accuracy than the film images for two of the observers.

Well productivity controlling factors in crystalline terrains of southeastern Brazil

Over the last decades, increasing water demands have fostered research to obtain high well yields in crystalline terrains where, besides the intrinsic properties of rocks, the groundwater flow depends on several factors. The depth of the wells, the lithotypes, the presence and thickness of sedimentary coverings and weathered layers, the landforms, the geological structures, and the effects of tectonic stresses are among the most investigated factors considered as determinant of well productivity. The influence of these factors on productivity of wells that exploit the Crystalline Aquifer System in the Jundiai-River Catchment, southeastern Brazil, is investigated in this work. The largest region of the studied area is located on the Precambrian Basement, partially covered by sedimentary deposits. The results show that the sedimentary deposits and the weathered layer are important for high well yield, but it also depends on the existence of a net of open fractures, in order to maintain high productivity. The sites that have more possibility of occurrence of such structures are the regional shear and fault zones and other minor structures with NW-SE and E-W directions, which characterize areas subjected to transtensional stress related to the neotectonics.

Effects of ion beam on nanoindentation characteristics of glassy polymeric carbon surface

Glassy polymeric carbon (GPC) is a useful material for medical applications due to its chemical inertness and biocompatible characteristics. Mitral and aortic and hydrocephalic valves are examples of GPC prosthetic devices that have been fabricated and commercialized in Brazil. In this work, ion beam was used to improve the mechanical characteristics of GPC surface and therefore to avoid the propagation of microcracks where the cardiac valves are more fragile. A control group of phenolic resin samples heat-treated at 300, 400, 700, 1000, 1500, and 2500 degrees C was characterized by measuring their hardness and Young's reduced elastic modulus with the depth of indentation. The control group was compared to results obtained with samples heat-treated at 700, 1000, and 1500 degrees C and bombarded with energetic ions of silicon, carbon, oxygen, and gold at energies of 5, 6, 8, and 10 MeV, respectively, with fluences between 10x10(13) and 10x10(16) ions/cm(2). GPC nonbombarded samples showed that hardness depends on the heat treatment temperature (HTT), with a maximum hardness for heat treatment at 1000 degrees C. The comparison between the control group and bombarded group also showed that hardness, after bombardment, had a greater increase for samples prepared at 700 degrees C than for samples prepared at higher temperatures. The Young's elastic modulus presents an exponential relationship with depth. The parameters obtained by fitting depend on the HTT and on the ion used in the bombardment more than on energy and fluence. The hardness results show clearly that bombardment can promote carbonization, increase the linkage between the chains of the polymeric material, and promote recombination of broken bonds in lateral groups that are more numerous for samples heat-treated at 700 degrees C. (c) 2004 Elsevier B.V. All rights reserved.

Effects of Antibacterial Agents on Dental Pulps of Monkeys Mechanically Exposed and Contaminated.

The purpose of this study was to compare the effectiveness of antibacterial agents and mineral trioxide aggregate in the healing of bacterial contaminated primate pulps. Study Design: The experiment required four adult male primates (Cebus opella) with 48 teeth prepared with buccal penetrartions into the pulpal tissues. The preparations (Cebus opella) with 48 teeth prepared with buccal penetrations into the exposed to cotton pellets soaked in a bacterial mixture consisting of microorganisms normally found in human pulpal abscesses obtained from the Endodontic Clinic of UNESP. Following bacterial inoculation (30 minute exposure), the pulpal tissue was immediately treated with either sterile saline, Cipro HC Otic solution (12), diluted Buckley formecresol solution (12) or Otosporin otic solution (12) for 5 minutes. After removal of the pellet, hemostasis was obtained and a ZOE base applied to the DFC treated pulps and the non-treated controls (12). After hemostasis, the other exposed pulps were covered with mineral trioxide aggregate (ProRoot). The pulpal bases were all covered with a RMGI (Fuji II LC). The tissue samples were collected at one day, two days, one week and over four weeks (34 days). Results: Following perfusion fixation, the samples were demineralized, sectioned, stained and histologically graded. After histologic analysis, presence of neutrophilic infiltrate and areas of hemorrhage with hyperemia were observed . The depth of the neutrophilic infiltrate depended on the agent or material used. The pupal tissue treated with Otic suspensions demonstrated significantly less inflammation (Kruskal Wallis non parametric analysis, H=9.595 with 1 degree of freedom; P=0.0223) than the formocresol and control groups. The hard tissue bridges formed over the exposure sites were more organized in the MTA treatment groups than in the control and ZOE groups (Kruskal Wallis non parametric analysis, H=18.291 with 1 degree of freedom; P=0.0004). Conclusions: Otic suspensions and MTA are effective in treating bacterial infected pulps and stimulate the production of a hard tissue bridge over the site of the exposure.

Effect of Hydrogen Peroxide at 35% on the Morphology of Enamel and Interference in the De-remineralization Process: An In Situ Study

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