Esta tese foi conduzida com o objetivo de avaliar a exigência do micromineral cobre para matrizes de frangos de corte. Cento e vinte reprodutoras de frangos de corte Cobb 500, com 20 semanas de idade, foram distribuídas aleatoriamente em gaiolas individuais. Depois de alimenta-las por 4 semanas com a dieta deficiente em cobre, as galinhas receberam dietas com níveis graduados de suplementação de cobre (0,0; 3,5; 7,0; 10,5; 14, and 17,5 ppm), utilizando sulfato de cobre (CuSO4 5H2O), totalizando níveis de 2,67; 5,82; 9,38; 12,92; 16,83; 20,19 ppm de cobre analisado na dieta por 20 semanas. As estimativas da exigência de cobre foram feitas utilizando os modelos: exponencial assimptótico (EA), broken line com quadrática (BLQ), e quadrática polinomial (QP). Os requerimentos de cobre obtidos para a produção de ovos (%) e produção total de ovos incubáveis por galinha foram 6,2, 7,3, 12,9 ppm e 8,1, 9,0 e 13,4 ppm, respectivamente usando os modelos EA, BLQ e QP. O modelo QP foi o único que se ajustou para o número total de ovos por galinha, fornecendo 13,1 ppm de cobre como requerimento. A hemoglobina, hematócrito e concentração de cobre no soro das galinhas tiveram os requerimentos estimados em 13,9, 11,3, 18,5 ppm, e 14,6, 13,0, 19,0 ppm, e16,2, 14,6 e 14,2 ppm, respectivamente para os modelos EA, BLQ e QP. O modelo QP foi o único que se ajustou para o número total de ovos por galinha, fornecendo 13,1 ppm de cobre como requerimento. A hemoglobina, hematócrito e concentração de cobre no soro das galinhas tiveram os requerimentos estimados em 13,9, 11,3, 18,5 ppm, e 14,6, 13,0, 19,0 ppm, e16,2, 14,6 e 14,2 ppm, respectivamente para os modelos EA, BLQ e QP. A hemoglobina dos pintos recém-eclodidos não foi afetada pelos níveis de cobre da dieta, enquanto os requerimentos para o hematócrito, peso corporal e comprimento foram de 10,2, 12,3, 13,3 ppm usando os modelos EA, BLQ e QP, e 6,8, 7,1 ppm e 12,9, 13,9 ppm utilizando os modelos EA, BLQ e QP, respectivamente. A máxima resposta para peso do ovo, conteúdo de cobre na gema, espessura da membrana da casca do ovo foram obtidas usando 14,9, 12,7, 15,1 ppm, 15,0, 16,3, 15,7 ppm, e 7,3 7,8, 14,0 ppm de cobre, respectivamente para os modelos EA, BLQ e QP. As porcentagens de gema e albúmen foram ajustadas apenas pelo modelo QP e obtiveram requerimentos estimados em 11 ppm e 11,3 ppm, respectivamente, enquanto a espessura da camada mamilar da casca do ovo foi maximizada com 10,6, 10,1 e 14,4 ppm de cobre usando os modelos EA, BLQ e QP, respectivamente. A média de todos os requerimentos de cobre estimados no presente estudo foi 12,5 ppm. / This thesis was conducted with the objective of evaluating the Cu requirement of broiler breeder hens. One hundred and twenty Cobb 500 hens, 20 weeks of age were randomly allocated into individual cages with the objective of estimating Cu requirements. After being fed a Cu deficient diet for 4 wks, hens were fed diets graded increments of supplemental Cu (0.0; 3.5; 7.0; 10.5; 14, and 17.5 ppm) from Cu sulfate (CuSO4 5H2O), totalizing 2.67; 5.82; 9.38; 12.92; 16.83; 20.19 ppm analyzed Cu in feeds for 20 wks. Estimations of Cu requirements were done using exponential asymptotic (EA), broken line quadratic (BLQ), and quadratic polynomial (QP) models. Cu requirements obtained for hen day egg production and total settable eggs per hen were 6.2, 7.3, 12.9 ppm and 8.1, 9.0 and 13.4 ppm, respectively using EA, BLQ and QP models. The QP model was the only one having a fit for total eggs per hen with 13.1 ppm Cu as requirement. Hemoglobin, hematocrit and serum Cu from hens had requirements estimated as 13.9, 11.3, 18.5 ppm and 14.6, 13.0, 19.0 ppm and 16.2, 14.6, 14.2 ppm, respectively for EA, BLQ and QP models. Hatching chick hemoglobin was not affected by dietary Cu whereas requirements estimated for hatching chick hematocrit, body weight and length were 10.2, 12.3, 13.3 ppm using EA, BLQ and QP models, and 6.8, 7.1 ppm and 12.9, 13.9 ppm Cu using EA and BLQ models, respectively. Maximum responses for egg weight, yolk Cu content, and eggshell membrane thickness were 14.9, 12.7, 15.1 ppm, 15.0, 16.3, 15.7 ppm and 7.3, 7.8, 14.0 ppm Cu, respectively for EA, BLQ and QP models. Yolk and albumen percentage were only adjusted with the QP model and had requirements estimated at 11.0 ppm and 11.3 ppm, respectively, whereas eggshell mammillary layer was maximized with 10.6, 10.1 and 14.4 ppm Cu using EA, BLQ and QP models, respectively. The average of all Cu requirement estimates obtained in the present study was 12.5 ppm Cu.

Este estudo avaliou o efeito de fontes e níveis de suplementação de selênio (Se) em dietas de aves reprodutoras pesadas sobre produção de ovo e a concentração de Se no conteúdo total do ovo. Foram utilizadas 50 reprodutoras Cobb 500 de 22 semanas, alojadas individualmente e alimentadas com dieta basal sem a suplementação de Se por três semanas. Após as aves receberam cinco tratamentos dietéticos com 10 repetições de uma ave cada, sendo compostos por selenito de sódio (inorgânico; Na2SeO3, 45% Se) e Zn-LSe- metionina (orgânico; ZnSeMet, 0,1% Se), como segue: T1- 0,15% inorgânico; T2- 0,30% inorgânico; T3- 0,15% orgânico; T4- 0,30% orgânico; T5- 0,15% inorgânico e 0,15% orgânico. Avaliações foram realizadas em dois períodos de 4 semanas. A produção de ovo e o peso do ovo foram diariamente registrados e a gravidade específica foi medida duas vezes por semana até o final do estudo. No primeiro período os animais alimentados com 0,30 ppm de Se orgânico apresentaram maior percentual de produção de ovo (P < 0,05), sendo que, no segundo período, nenhuma diferença foi observada entre os tratamentos (P > 0,05). As avaliações entre os períodos apresentaram que o peso do ovo não foi diferente (P > 0,05), sendo que a gravidade específica foi menor no segundo período (P < 0,05) e a concentração de Se no ovo aumentou com o tempo de suplementação (P < 0,05), independentemente da fonte de Se suplementada. A comparação dos tratamentos que continham apenas uma única fonte de Se demonstrou que a concentração de Se no ovo foi maior com a suplementação do maior nível de ZnSeMet (P < 0,05). Entretanto, a suplementação com a combinação das fontes (Na2SeO3 e ZnSeMet) produziu similares concentrações de Se no ovo. O aumentou da dose de selenito de sódio de 0,15 para 0,30 ppm não foi acompanhado por um aumento da deposição de Se no ovo. / This study evaluated effects of sources and levels of Se in broiler breeder diets on egg production and Se concentration in eggs. Fifty Cobb 500 hens 22 wks of age were individually placed in steel cages and fed a basal diet without Se supplementation for 3 wks. Birds were then provided five dietary treatments with 10 replicates of one individual hen, which had dietary selenium supplied from sodium selenite (inorganic; Na2SeO3, 45% Se) and/or from Zn-LSe- methionine (organic; ZnSeMet, 0.1% Se) as follow: T1- 0.15% Se from Na2SeO3; T2- 0.30% Se from Na2SeO3; T3- 0.15% Se from ZnSeMet; T4- 0.3ç0% Se from ZnSeMet; T5- 0.15% Se from Na2SeO3 + 0.15% Se from ZnSeMet. Evaluations were conducted in two periods of 4 wks each. Experimental diets were prepared through the supplementation of corn-soybean meal diets. Egg production and egg weight were recorded daily, whereas specific gravity was measured twice a wk towards the end of the study. In the first period, the hens fed 0.30 ppm of organic Se produced more eggs (P < 0.05) whereas no difference (P > 0.05) in egg production was found in the second period. Period evaluations showed that egg weight was not different (P > 0.05), whereas specific gravity decreased (P < 0.05) and Se concentration in eggs increased (P < 0.05) in the second period, regardless of Se source. The comparison between treatments with single Se sources demonstrated that the concentration of Se in eggs was greater with the highest level of ZnSeMet (P <0.05) and, the supplementation of a combination of sources (Na2SeO3 and ZnSeMet) produced similar concentrations of Se in the egg (P <0.05). However, increasing the dose of sodium selenite from 0.15 to 0.30 ppm was not accompanied by increased deposition of Se in the egg.

Made available in DSpace on 2014-10-09T12:25:58Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:24Z (GMT). No. of bitstreams: 1 00988.pdf: 3339929 bytes, checksum: 27ead5c2fe041a5b93b6fa5c9a4df73f (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The need to improve the reproductive performance of broiler breeders have been contributed to development of new concepts and products in animal nutrition. Carophyll Red® has in your composition canthaxantin. Has been accepted that canthaxantin has high antioxidant capacity.The 25-(OH)D3 (25-hydroxycholecalciferol), an intermediary between the vitamin D3 and the active form of this vitamin D. This is allied with the metabolism and transfer of calcium from the shell to the embryo. HY-D® is a form of vitamin D, his composition. Rovimix® Maxichick is the association of canthaxanthin and 25-(OH)D3. The experiment was conducted with the objective to evaluate the use of canthaxanthin and/or 25- hydroxycholecalciferol (25-(OH)D3) on performance of broiler breeders. Its was used 264 females and 24 males COBB 500® broiler breeders with 25 to 52 weeks of age. The diets were composed basically of vegetable ingredients, based on corn and soybean meal. It was used four treatments: 1 - control diet, 2 - control diet with addition of 25-(OH)D3, 3 - control diet with addition of canthaxanthin (CX), 4 - control diet with a combination of these two active ingredients (25-(OH)D3 + CX). The parameters evaluated were body weight, laying rate, egg weight, specific gravity, weight of albumen, yolk and shell percentage, albumen, yolk and shell, yolk color and oxidation. To evaluate the laying rate were performed six daily collections during the experimental period. Eggs collect a day of week were used for all others analysis. The egg production rates were not affected by different treatments (P=0.5151).The egg, yolk and albumen weight s and specific gravity were not affected by treatments (P>0.05). Broiler breeders fed canthaxanthin in diet had highest deposition of carotenoids in the yolk. / A necessidade de melhorar o desempenho reprodutivo de matrizes de corte contribuí para os conceitos de desenvolvimento e novos produtos na alimentação animal. Carophyll Red® tem na sua composição cantaxantina, a qual é estudada pela sua capacidade antioxidante 25 - (OH)D3 (25-hidroxicolecalciferol), um intermediário entre a vitamina D3 e da forma ativa da vitamina D. Esta, é aliada com o metabolismo e transferência de cálcio da casca para o embrião. HY-D® possui na sua composição 25 - (OH)D3. Rovimix Maxichick® é a associação de cantaxantina e 25 - (OH)D3. O experimento foi conduzido com o objetivo de avaliar o uso da cantaxantina e / ou 25 - (OH)D3 sobre o desempenho de matrizes de corte, Cobb® entre 25e 52 semanas de idade. As dietas foram compostas basicamente de ingredientes vegetais, tendo por base milho e farelo de soja. Foram utilizados quatro tratamentos: 1 - dieta controle (sem aditivos em estudo), 2 - dieta controle com adição de 25 - (OH) D3, adicionando o produto HY-D®, 3 - dieta controle com adição de cantaxantina (CX) através da inclusão do produto Carophyll Red®, 4 - dieta com a associação dos princípios ativos (25 - (OH)D3 + CX) com o uso de Rovimix® MaxiChick. Foram avaliados o peso corporal, taxa de postura, peso dos ovos, densidade específica de ovos, peso do albúmen, gema e casca e porcentagem de albúmen, gema e casca, coloração da gema e a peroxidação de lipídios da gema. Para avaliar a taxa de postura foram realizadas seis coletas diárias durante todo o período experimental. Todos os ovos de uma coleta por semana foram utilizados para análise dos outros parâmetros. Os diferentes tratamentos não afetaram a taxa postura no período (P=0,5148). A gravidade específica, pesos de gema, albúmen e casca de ovo também não foram afetados pelos tratamentos (P>0,05). Matrizes pesadas que receberam cantaxantina na dieta, apresentaram maior deposição de carotenóides na gema.

Earthquake safety engineering of nuclear power plant structures poses several challenges to the analyst and designer. These problems are characterized by highly transient and dynamic nature of earthquake induced excitations, random nature of details of support motions (in terms of duration, frequency content, amplitude modulation, multiple components, and spatial variability), nonlinear nature of structural behavior, geometrical complexity of the primary and a large number of secondary systems (such as, for example, piping, rotors, and machine panels), soil-structure interactions, demands on high level of safety expected of these structures, and general paucity of recorded data on strong ground motions appropriate for the given site. Probabilistic methods offer the most rational framework to base design decisions for this class of problems. The work reported in the present thesis belongs to this broad area of research. We focus attention on studying two classes of nuclear power plant components, namely, a pipework in the heat exchanger segment, and, control and safety rod drive mechanism (CSRDM) and investigate their performance by taking into account complicating features such as differential seismic support motions across multiple supports, nonlinearities at support locations, random nature of dynamic loads and uncertainties in system parameters. Response measures include peak responses, reliability against specified performance criterion, measures of uncertainties in response variables of interest. Chapter-1 provides the functional details of nuclear power plant structures that includes reactor assembly and heat transport system assembly, CSRDM, heat transfer piping networks, and nonlinear supporting devices (such as rod, spring, guide supports, limiters, and snubbers). The discussion brings out the structural mechanics issues that need attention while analyzing seismic response of some of these components. Chapter-2 provides a brief review of literature covering the following topics: Monte Carlo simulation based methods for static and dynamic reliability analysis problems, digital simulation of random variables and processes, treatment of non-Gaussianity in simulations, strategies for variance reduction, models for uncertainty in response using limited samples, data based extreme value analysis, studies on multi-supported piping networks under differential seismic inputs and seismic performance of CRDM structures. The study identifies specific issues related to numerical simulation of nonlinear dynamic response of multisupported pipeworks to differential seismic inputs, uncertainty propagation and reliability modeling in seismic response of pipeworks and CSRDM using Monte Carlo simulations with variance reduction, data based extreme value analysis, and uncertainty propagation using limited samples as topics requiring further research. The problems of numerical simulation of nonlinear multisupported piping systems subjected to differential seismic support motions and drop time characterization of CSRDM structure during a seismic event are considered in Chapter-3. It is noted that commercially available professional finite element analysis (FEA) softwares do not offer a direct means to tackle this class of problems. On the other hand, FEA packages are best suited to produce acceptable FE models which take into account the geometrical complexities of the structures. Thus, the reasonable way to move forward would be to develop external interfaces that take advantage of FE modeling capabilities of professional packages and at the same time enable treatment of complexities associated with differential support motions, nonlinearities and axial rigid motions of subsystems as in CSRDM. The work reported in Chapter-3 describes the efforts expended in achieving this objective. Here the given built-up structure is divided in to a set of linear substructures each of which are modeled using FE analysis procedures. The proposed scheme allows for these FE models to reside in professional FE analysis codes. An iterative time domain scheme for modeling the interaction forces between these substructures is discussed. The set of governing equations of motion are developed in terms of normal modes of substructures in their uncoupled states. A suite of benchmark problems are first employed to validate the procedure developed. Subsequently, the earthquake induced dynamic response of CSRDM structure and the pipeline running between IHX and secondary sodium pump in a typical fast breeder reactor is simulated. The algorithm for simulation of dynamic response of CSRDM and multi-supported pipelines under differential support motions developed in Chapter-3 is employed in Chapter-4 to investigate the questions concerning influence of uncertainties in specifying the loads and the system parameters on the system response. Specifically, the study focuses on quantifying uncertainty in system response characteristics based on limited number of Monte Carlo simulations of the response. For this purpose we draw upon an earlier work by Wilks which specifies the number of samples needed to estimate γ th percentile point of a random variable with β level of confidence. We explore in this Chapter, the application of this idea in the analysis of nonlinear, randomly parametered, dynamical systems under stochastic excitations. In Chapter-5 we turn our attention to the modeling of aseismic reliability of the nonlinear pipework under differential support motions and the CSRDM structure. The performance functions considered for the piping structure are in terms of highest displacements and stresses over a specified time durations while for CSRDM, the performance function is in terms of scram time being less than a specified time duration. We tackle the first problem by using theory of data based extreme value analysis while the second problem is addressed using an adaptive importance sampling strategy. The contributions here pertain to the exploration of data based extreme values analysis as applied to an industrial scale structure and improvisation of algorithmic modifications in the development of adaptive importance sampling density functions. This improvisation consists of selection of sampling points as a judicious mix of points from both safe and unsafe regions. This is shown to reduce the strong correlations that otherwise would be present if samples are taken only from the unsafe region. These studies demonstrate how Monte Carlo simulations with limited samples can be utilized to draw useful conclusions on structural reliability. Chapter-6 summarizes the main contributions made in the thesis and makes a few suggestions for further research. There are five annexures in the thesis. Annexure-1 contains listing of Matlab m-files used for solving illustrative problems in Chapter-2. The details of FE modeling of multisupported system under differential support motions and the details of substructuring scheme used in modeling of such systems with local nonlinearities are provide in Annexure-2. The details of material and geometry of CSRDM structure are provided in Annexure-3. Annexure-4 summarizes the main details of hypothesis tests used in data based extreme value analysis. The algorithms used for converting response spectra into compatible power spectral density functions are described in Annexure-5.

In der vorliegenden Arbeit wird die Optimierung des REXEBIS-Ladungsbrüters an der ISOLDE präsentiert. Die REXEBIS in der aktuellen Konfiguration erzeugt eine Elektronenstromdichte in der Fallenregion bei 2 T von 200A/cm² und wird bis zu ihren physikalischen Grenzen optimiert. Um diese Begrenzung zu überwinden wurde eine neue Elektronenkanone, die HEC²-Elektronenkanone, in Kooperation mit BNL konstruiert und an der TestEBIS in Betrieb genommen. Diese Elektronenkanone verspricht eine Elektronenstromdichte von mehr als 10 kA/cm² bei 5T, welche die Ladungsbrütungszeit entscheidend verkürzt. In dieser Dissertation werden neuartige Simulationstechniken vorgestellt, welche die Inbetriebnahme durch Untersuchung der Mechaniken von auftretenden Verlustströmen beschreiben. Dazu wird der Elektronenkollektor der TestEBIS nach Kompatibilität bezüglich der HEC²-Elektronenkanone, die nahe derer Designwerte betrieben wird, evaluiert. Die gewonnenen Erfahrungen von der Inbetriebnahme der HEC²-Elektronenkanone und den etablierten, numerischen Techniken führen zur Entwicklung einer kleineren hochkomprimierenden Elektronenkanone für medizinische Anwedungen, die MEDeGUN. Diese Elektronenkanone sollte einen qualitativ hochwertigen Elektronenstrahl generieren, welcher eine Elektronenstromdichte von 7.5 kA/cm² in der Fallenregion bei 5 T axialen Magnetfeld erzeugt. Eine EBIS/T, ausgestattet mit einer MEDeGUN, wird bezüglich Pulsfrequenz und bereitgestellten Ionenstrom zu Hochfrequenz-Therapiezentren der zweiten Generation kompatibel sein. / In this thesis the optimization of the REXEBIS charge breeder at the ISOLDE facility is presented. REXEBIS in its current state provides a current density of 200A/cm² inside the trapping region at 2 T and will be optimized to the physical limit of its design. To overcome this limit a new electron gun, the HEC² gun, was designed in collaboration with the BNL and is in commission at TestEBIS. This electron gun promises a current density of >10 kA/cm², which decreases the charge breeding time significantly. This thesis presents novel simulation techniques supporting the commissioning phase by explaining the sources of occurring loss current and, in addition, evaluate the currently installed collector for compatibility with the HEC² gun operating at its design limit. The experience gained from the commission of the HEC2 gun and the established numerical techniques lead to the development of a smaller high-compression electron gun for medical purposes, the MEDeGUN. This electron gun should provide a high-quality beam, which generates a calculated current density of 7.5 kA/cm² inside the trapping region immersed in a 5 T axial magnetic field. An EBIS/T equipped with a MEDeGUN will be compatible regarding the pulse frequency and deliver the mandatory ion current required for second generation therapy centers.

Leg problems and disorders are of major concern for the poultry industry and animal welfare. Previous studies suggest that it may be possible to improve skeletal characteristics through nutrition. Omega-3 fatty acids, including Docosahexaenoic acid (DHA), are essential nutrients and are known to play an important role in bone tissue development. FORPLUS™ (Alltech, Inc.) is an unextracted, whole-cell microalgae (Aurantiochytrium limacinum CCAP 4087/2) that contains 64% fat and 16% DHA. Zinc (Zn) is a trace element and essential nutrient for growth and skeletal development. Bioplex® Zn (Alltech, Inc.) is a Zn proteinate that has been shown to be more bioavailable to broiler chickens compared to inorganic sources of Zn. One objective of this research was to investigate the effects of 2 dietary levels of FORPLUS™ (0% vs. 2%) and 2 dietary Zn sources (ZnO vs. Bioplex® Zn) on skeletal characteristics and reproduction of broiler breeders. Breeders were maintained on these diets throughout the entire pullet and layer phases. Subsequent studies were conducted to evaluate the effect of breeder diet and offspring dietary Zn sources (ZnO vs. Bioplex® Zn) and microalgae supplementation (0% vs. 1%) on offspring performance and skeletal characteristics. During the broiler breeder pullet phase, dietary supplementation of 2% FORPLUS™ increased (P < 0.05) femur ash content and length. Pullet uniformity was in increased (P < 0.05) by Bioplex® Zn vs ZnO when microalgae was not included in the diet. Hen day production (HDP) was increased (P < 0.05) by ZnO vs. Bioplex® Zn supplementation during post-peak lay. During post-peak lay, hatchability and hatch of fertile eggs were improved (P < 0.05) by dietary supplementation of 2% FORPLUS™ or Bioplex® Zn in breeder diets, however egg weight, egg yolk weight, offspring hatch weight, and offspring body weight gain (BWG) significantly were decreased (P < 0.05) by 2% FORPLUS™. Bioplex® Zn in breeder diets increased (P < 0.05) growth plate zone heights, bone-specific alkaline phosphatase enzyme activity, and dimensions of offspring bones at hatch. At 3 weeks of age, offspring from breeders fed Bioplex® Zn during peak-lay had greater (P < 0.05) Zn content in tibia ash and bone dimensions, while offspring from breeders fed 2% FORPLUS™ vs. 0% FORPLUS™ had longer (P < 0.05) femurs. No interaction effect of breeder diet and offspring diet on early performance was observed. Offspring fed diets containing Bioplex® Zn vs. ZnO had greater (P < 0.05) body weight (BW) and tibia dimensions at 3 wk of age. Offspring fed diets containing 1% FORPLUS™ had decreased feed conversion (feed intake: BWG), but no main effects were observed on skeletal characteristics. Overall, dietary microalgae supplementation in broiler breeder diets improved early bone development in broiler breeders, early bone development in broiler breeder offspring, and hatchability of offspring during post-peak lay, while Bioplex® Zn supplementation in broiler breeder diets improved broiler breeder pullet uniformity, offspring hatchability during post-peak lay, embryonic skeletal development of offspring, and offspring bone quality. Bioplex® Zn in offspring diets also improved offspring early growth performance and leg bone morphology.

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Nuclear Engineering, 1978 / Includes bibliographical references. / Ph. D. / Ph. D. Massachusetts Institute of Technology, Department of Nuclear Engineering

Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Bibliography: leaves 289-295. / by Bahman Atefi. / Sc.D.

Thesis. 1978. M.S.--Massachusetts Institute of Technology. Dept. of Nuclear Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Includes bibliographical references. / M.S.