Teste de envelhecimento acelerado para avaliação do potencial fisiol��gico de sementes de grama-bermuda

A utiliza����o de sementes para forma����o de gramados esportivos e ornamentais tem assumido grande import��ncia no Brasil, principalmente pelo baixo custo em rela����o �� forma����o por placas de tapetes naturais. As bermudas [Cynodon dactylon (L.) Pers] s��o as principais gramas utilizadas na forma����o de campos esportivos e, dentre os problemas enfrentados, destaca-se a dificuldade de estabelecimento adequado da cultura, fato que exige a utiliza����o de sementes de alto potencial fisiol��gico, de modo a permitir r��pida emerg��ncia e desenvolvimento das plantas. Assim, estudaram-se procedimentos para a condu����o do teste de envelhecimento acelerado para determinar o potencial fisiol��gico de sementes dessa esp��cie, incluindo a avaliação da efici��ncia do uso de solu����o saturada de NaCl como alternativa para a realiza����o do teste. Para tanto, cinco lotes de sementes foram submetidos aos testes de germina����o, emerg��ncia de pl��ntulas e envelhecimento acelerado (per��odos de 48, 72 e 96 h, a 41 e 45 ��C, com e sem o uso de solu����o saturada de NaCl). O experimento foi conduzido em delineamento inteiramente casualizado. O envelhecimento acelerado com o uso de solu����o saturada de NaCl, dentre os procedimentos estudados, �� o m��todo mais adequado para avaliação do potencial fisiol��gico de sementes de grama-bermuda, sendo que a combina����o 45 ��C/48 h �� eficiente para a classifica����o dos lotes em diferentes n��veis de vigor.

Metodologia estat��stica na solu����o do problema do caixeiro viajante e na avaliação de algoritmos : um estudo aplicado �� transgen��tica computacional

The problems of combinatory optimization have involved a large number of researchers in search of approximative solutions for them, since it is generally accepted that they are unsolvable in polynomial time. Initially, these solutions were focused on heuristics. Currently, metaheuristics are used more for this task, especially those based on evolutionary algorithms. The two main contributions of this work are: the creation of what is called an -Operon- heuristic, for the construction of the information chains necessary for the implementation of transgenetic (evolutionary) algorithms, mainly using statistical methodology - the Cluster Analysis and the Principal Component Analysis; and the utilization of statistical analyses that are adequate for the evaluation of the performance of the algorithms that are developed to solve these problems. The aim of the Operon is to construct good quality dynamic information chains to promote an -intelligent- search in the space of solutions. The Traveling Salesman Problem (TSP) is intended for applications based on a transgenetic algorithmic known as ProtoG. A strategy is also proposed for the renovation of part of the chromosome population indicated by adopting a minimum limit in the coefficient of variation of the adequation function of the individuals, with calculations based on the population. Statistical methodology is used for the evaluation of the performance of four algorithms, as follows: the proposed ProtoG, two memetic algorithms and a Simulated Annealing algorithm. Three performance analyses of these algorithms are proposed. The first is accomplished through the Logistic Regression, based on the probability of finding an optimal solution for a TSP instance by the algorithm being tested. The second is accomplished through Survival Analysis, based on a probability of the time observed for its execution until an optimal solution is achieved. The third is accomplished by means of a non-parametric Analysis of Variance, considering the Percent Error of the Solution (PES) obtained by the percentage in which the solution found exceeds the best solution available in the literature. Six experiments have been conducted applied to sixty-one instances of Euclidean TSP with sizes of up to 1,655 cities. The first two experiments deal with the adjustments of four parameters used in the ProtoG algorithm in an attempt to improve its performance. The last four have been undertaken to evaluate the performance of the ProtoG in comparison to the three algorithms adopted. For these sixty-one instances, it has been concluded on the grounds of statistical tests that there is evidence that the ProtoG performs better than these three algorithms in fifty instances. In addition, for the thirty-six instances considered in the last three trials in which the performance of the algorithms was evaluated through PES, it was observed that the PES average obtained with the ProtoG was less than 1% in almost half of these instances, having reached the greatest average for one instance of 1,173 cities, with an PES average equal to 3.52%. Therefore, the ProtoG can be considered a competitive algorithm for solving the TSP, since it is not rare in the literature find PESs averages greater than 10% to be reported for instances of this size.

Efic��cia do teste de acidez graxa na avaliação da qualidade do caf�� Ar��bica (Coffea arabica L.) submetido a diferente per��odos e temperaturas de secagem

This work had the aim of evaluating the effect of different temperatures and pre-drying periods on yard on the chemical composition and quality of the beverage of peeled cherry coffee. Temperatures of 40 degrees C, 50 degrees C and 60 degrees C were used in the mass with air flow of 20m(3)m(-1)m(2). After drying, the visible defects of the coffee samples were removed. For evaluation of quality, the following analyses were performed: sensorial analyses, total sugars, reducing sugars and non-reducing sugars, electrical conductivity, potassium leaching and fatty acidity. One verified that lower drying temperature and greater pre-drying period had contributed for the attainment of a better quality drink. The increase of temperature and pre-drying periods decreased the non-reducing sugars content while the values of reducing sugars increased. The electrical conductivity, potassium leaching and fatty acidity increased significantly with the rise of temperature and potassium leaching reduced with increasing of the pre-drying period. The fatty acidity test showed to be sensible to the drying temperature.

Caracteriza����o de escovas de grafite e avaliação do seu desempenho em função da microestrutura

The electric can be converted into thermal, luminous, electromagnetic, and also in mechanical energy. In this context the electric engines plays a fundamental role, specially that they work very below of its nominal capacity, with consequent decrease load density. In industrial environment, these characteristics of work of DC engines had also generated an extreme consumption of coal brushs and attack in the commutator reducing the useful life of the engine and increasing maintenance demand and cost. The general objective of the present work is to study the influence of the granulometry of the coal brush used in DC engines with the resistance to the consumption of the same ones, as well as in the performance presented by the commutator of the engine. Additionally, determining the measurable and not measurable profits when the brush used is adjusted to the application. The brushes had been produced by an industry of the sector and tested in industrial environment to evaluate their performance and consumption. Preliminary results evidence a substantial improvement in the performance of these brushes in function of its microstructure and the application in which it is used

Avaliação da deposi����o da calda de pulveriza����o em função da densidade populacional de Brachiaria plantaginea, do volume e do ��ngulo de aplica����o

O presente trabalho teve por objetivo avaliar a quantidade de calda de pulveriza����o depositada nas folhas de Brachiaria plantaginea, em aplica����es de p��s-emerg��ncia precoce, em que se variou o volume de calda de pulveriza����o, a densidade de plantas m-2 e o ��ngulo de posicionamento da ponta de pulveriza����o na barra de aplica����o. Para isso, foram conduzidos tr��s experimentos em condi����es de laborat��rio. Nestes estudos, o volume de calda de pulveriza����o foi obtido por meio da varia����o da velocidade de deslocamento de um ve��culo composto por plataforma e quatro rolamentos tracionados por um motor el��trico. Foi utilizada a ponta de pulveriza����o XR Teejet 8001 EVS, na press��o de 241,4 kPa. O delineamento experimental utilizado foi o inteiramente casualizado, com cinco repeti����es. No primeiro experimento, os volumes utilizados foram de 1147,57; 860,68; 573,78; 459,02; 344,27; 229,51; 114,75; e 57,37 L ha-1 de calda de pulveriza����o, com densidade de 600 plantas m-2. No segundo experimento foram estudadas as densidades de 300, 600, 900 e 1.200 plantas m-2; neste caso, utilizou-se o volume de 229,51 L ha-1 de calda de pulveriza����o. No terceiro experimento avaliou-se o posicionamento do ��ngulo da ponta de pulveriza����o na barra de aplica����o e utilizou-se a densidade de 600 plantas m-2. Estudaram-se os ��ngulos de -30��, -15��, 90��, +15�� e +30�� e os volumes de calda de pulveriza����o de 198,76; 221,69; 229,51; 221,69; e 198,76 L ha-1, respectivamente. Foram adotados sinais negativos para o sentido de deslocamento do ve��culo e sinais positivos para o sentido contr��rio ao deslocamento. As avalia����es do dep��sito de calda de pulveriza����o, na planta e no solo, foram feitas utilizando-se condutividade el��trica. A porcentagem de dep��sito de calda de pulveriza����o nas plantas de B. plantaginea foi incrementada com a redu����o do volume de calda pulverizada por hectare. O dep��sito de calda por planta foi maior nas densidades maiores de plantas. O ��ngulo de posicionamento da ponta de pulveriza����o na barra de aplica����o incrementou o dep��sito de calda nas plantas de B. plantaginea, quando comparado com o ��ngulo de 90��.

Avaliação da qualidade fisiol��gica de sementes de mamoneira (Ricinus communis L.) pelo teste de tetraz��lio

Objetivou-se com esse trabalho estabelecer par��metros para a avaliação da qualidade fisiol��gica de sementes de mamoneira (Ricinus communis L.) pelo teste de tetraz��lio. Avaliaram-se cinco lotes de sementes quanto �� viabilidade e ao vigor pelo teste de tetraz��lio e os resultados comparados aos obtidos nos testes de germina����o em areia, germina����o em papel, primeira contagem da germina����o em papel, emerg��ncia de pl��ntulas em campo, ��ndice de velocidade de emerg��ncia, classifica����o do vigor de pl��ntulas, comprimento das pl��ntulas, massa da mat��ria seca de pl��ntulas e envelhecimento acelerado. O delineamento experimental empregado foi o inteiramente casualizado, e a compara����o de m��dias realizada pelo teste de Tukey a 5% de probabilidade. Os resultados de viabilidade do teste de tetraz��lio se correlacionaram com o teste de germina����o em areia, com a emerg��ncia em campo e com o comprimento de pl��ntulas, e os de vigor do teste de tetraz��lio com a classifica����o do vigor de pl��ntulas. Concluiu-se que os par��metros estabelecidos s��o eficientes para a avaliação da viabilidade e promissores para a avaliação do vigor de sementes de mamoneira pelo teste de tetraz��lio.

Utiliza����o do teste de raios - x na avaliação dos efeitos da desseca����o e infesta����o em di��sporos de Canela-Batalha - Cryptocarya aschersoniana Mez (Lauraceae)

No presente trabalho, objetivou-se avaliar os efeitos da desseca����o e identificar les��es por preda����o por insetos, em di��sporos de canela-batalha (Cryptocarya aschersoniana Mez.), utilizando-se testes de raios X. Os danos provocados pela desseca����o foram dimensionados nas imagens e associados �� forma����o de pl��ntulas. Di��sporos rec��m-beneficiados (45 % de umidade e 37 % de germina����o) foram colocados para secar em sala climatizada (20 ��C e 60 % UR), dentro de bandejas pl��sticas em camada ��nica. Posteriormente, com o intuito de acelerar o processo de secagem, foram colocados em caixas de secagem com solu����o saturada de hidr��xido de s��dio (28 % UR) e amostrados com 45, 37, 35, 31 e 26 % de umidade. Para as radiografias, utilizou-se a intensidade de radia����o de 40 kVp e tempo de exposi����o de 1,5 minutos. Posteriormente, as radiografias foram fotografadas e as imagens analisadas em computador, sendo medido o afastamento entre o endocarpo e a semente. As sementes foram classificadas em sementes intactas, sementes com afastamento parcial, sementes com afastamento total e sementes predadas. Os testes de germina����o foram realizados sobre areia, em germinadores tipo Mangelsdorf a 25 ��C e luz branca constante. Pelos resultados, observa-se que a germina����o �� comprometida quando o teor de ��gua das sementes fica abaixo de 26 %. Nesse ponto, o afastamento entre o endocarpo e a semente �� de 0,65 mm. Houve uma correla����o positiva entre a viabilidade das sementes, avaliada pelo teste de germina����o, e o afastamento entre o endocarpo e a semente observado nas radiografias. A an��lise radiogr��fica possibilita identificar danos provocados por preda����o ap��s infesta����o por insetos.

Analysis of cardiovascular system responses to forced vital capacity in COPD

CONTEXTUALIZA����O: O teste de capacidade vital for��ada (CVF) �� rotineiramente realizado na avaliação da função pulmonar de pacientes com doen��a pulmonar obstrutiva cr��nica (DPOC). Entretanto, permanece pouco compreendida a influ��ncia do teste de CVF sobre o sistema cardiovascular de pacientes com DPOC. OBJETIVOS: Analisar o comportamento da frequ��ncia cardíaca (FC), press��o arterial (PA) e variabilidade da frequ��ncia cardíaca (VFC) no teste de CVF na DPOC. M��TODOS: Dezenove homens com DPOC (72 �� 7 anos, no est��gio de gravidade GOLD I=3, II=5, III=7 e IV=4 pacientes) realizaram a manobra de CVF e tiveram sua FC monitorada durante todo o exame, e a VFC analisada nos dom��nios do tempo (rMSSD) e da frequ��ncia (BF, AF e BF/AF) durante o repouso, antes e ap��s a melhor manobra de CVF. A PA foi analisada no repouso, imediatamente ao final da manobra de CVF e 10 minutos ap��s o t��rmino de todos os testes. RESULTADOS: Ao in��cio da manobra de CVF, a FC reduziu (p<0,001) e, em seguida, aumentou progressivamente at�� o final do teste (p<0,001). Ap��s t��rmino da manobra, a FC continuou a aumentar at�� atingir um pico (p<0,001) e depois caiu rapidamente a valores inferiores aos de repouso (p<0,001) e retornou ao seu valor basal. A PA e os ��ndices da VFC n��o sofreram altera����es nos per��odos analisados. CONCLUS��O: O teste de CVF influencia o comportamento da FC, sem alterar o seu controle auton��mico, bem como a PA em pacientes com DPOC nos per��odos analisados.

Avaliação da função pulmonar em obesos m��rbidos com sonol��ncia diurna excessiva

Background: Obesity impairment to the pulmonary function related to the magnitude of adiposity and is associated with excessive daytime sleepiness (EDS) and snoring, among others symptoms of respiratory disorders related to sleep. It is possible that obese individuals with excessive daytime sleepiness may make changes in lung function on spirometry monitored during the day as a consequence of fragmented sleep or episodes of nocturnal hypoventilation that cause respiratory and changes that can persist throughout the day. The combination of these findings alone sleepiness observed by subjective scales with pulmonary function in obese patients is unknown. Objective: To assess the influence of EDS and snoring on pulmonary function in morbidly obese and distinguish between different anthropometric markers, the snoring and sleepiness which the best predictors of spirometric function and respiratory muscle strength and endurance of these patients. Methods: We evaluated 40 morbidly obese markers on the anthropometric, spirometric respiratory variables, maximal inspiratory and expiratory pressures (MIP and MEP) and maximal voluntary ventilation (MVV) and the measured excessive daytime sleepiness (the Epworth sleepiness scale) and snoring (snoring scale of Stanford). The data were treated when the differences between the groups of obese patients with and without sleepiness, whereas the anthropometric variables, respiratory and snoring. Pearson's correlation was performed, and multiple regression analysis assessed the predictors of pulmonary function. For this we used the software SPSS 15.0 for windows and p <0.05. Results: 39 obese patients were included (28 women), age 36.92+11.97y, body mass index (BMI) 49.3+5.1kg/m��, waist-hip ratio (WHR) 0.96+0.07 and neck circumference (NC) 44.1+4.2 cm. Spirometric values and respiratory pressures were up 80% of predicted values, except for endurance (MVV <80%). Obese with EDS have lower tidal volume. Positive correlation was observed between BMI and EDS, EDS and NC and between snoring and BMI, and negative correlation between EDS and tidal volume (TV), and between snoring and snoring FVC and FEV1. In linear regression the best predictor of pulmonary function was snoring, followed by NC. NC has more obese with higher strength (MEP, p = 0.031) and endurance (MVV p = 0.018) respiratory muscle. Conclusion: Obese with EDS tend to have lower TV. In addition, snoring and NC can better predict pulmonary function in obese when compared with other anthropometric markers or EDS. Obese patients with higher NC tend to have greater capacity for overall strength of respiratory muscles, but may have low muscle endurance

Avaliação eletromiogr��fica de m��sculos inspirat��rios em hemipar��ticos / Eliete Moreira Cola��o

The objective was measured by surface electromyography (EMGs), the activity of inspiratory muscles during incremental test in subjects with hemiparesis and show its correlation with the Functional Independence Measure (FIM). Were included in the study 32 individuals hemiparetics and 14 healthy as control group. We performed an evaluation of lung function and anthropometric data. The EMGs were performed during the incremental test with Threshold �� (15, 30, 45 and 60% of MIP) and during maximal inspiratory pressure (MIP). The electromyographic findings were calculated by the signal amplitude (RMS). All data were initially analyzed by Kolmogorov-Smirnov, the anthropometric characteristics of both groups were tested with the Levene and then intra-subject analysis (hemiparetic hemithorax and healthy hemithorax) and inter-group analysis (experimental group and control group) by paired and non-paired Student t tests and Pearson correlation. In intra-subject comparison was observed less activation (p <0.01) of the sternocleidomastoid muscle, scalene and diaphragm paretic side in both sexes - for the Threshold �� incremental test (15, 30, 45 and 60% of the MIP) and during maximal inspiratory pressure (MIP). In inter-group comparison, there was reduced activity in the diaphragm and the scalene, in hemiparetics males and females, respectivelly, during the same test. Our results demonstrate the existence of reduced electromyographic activity of inspiratory muscles in hemiparetics, including changes between different genders and suggests the need of further studies to assess the effects of specific training of inspiratory muscles.

Avaliação das vari��veis cardiovasculares, capacidade de caminhar e n��vel de atividade f��sica de obesos m��rbidos antes e depois da cirurgia bari��trica

Morbidly obese patients present an increase in heart rate, blood pressure and perceived exertion besides lower walking ability compared to normal weight people. However, little is known about how these variables are presented after bariatric surgery. Moreover, despite the distance walked during the six-minute walk (6MWT) improve after surgery is not well established if the level of physical activity influences this improvement. Objective: To evaluate cardiovascular performance, perceived effort, ability of walking and physical activity level of patients with morbid obesity before and after bariatric surgery. Methods: The cardiovascular performance, perception of effort, the ability to walk and level of physical activity were assessed in 22 patients before (BMI = 50.4 kg/m2) and after (BMI = 34.8 kg/m2) bariatric surgery through the 6MWT. The heart rate, blood pressure and perceived exertion were assessed at rest, at the end of the 6MWT and in the second minute post-test (HR recovery). The ability to walk was measured by total distance walked at the end of the test while the level of physical activity was estimated by applying the Baecke questionnaire, analyzing domains occupation, leisure and locomotion and leisure and physical activity. Results: The HR at rest and recovery decreased significantly (91.2 �� 15.8 bpm vs. 71.9 �� 9.8 bpm, 99.5 �� 15.3 bpm vs 82.5 �� 11.1 bpm, respectively), as well as all the arterial pressure and perceived exertion after surgery. The distance achieved by the patients increased by 58.4 m (p = 0.001) postoperatively. Time postoperatively had correlation with the percentage of excess weight lost (r = 0.48, p = 0.02), BMI (r =- 0.68, p = 0.001) and the Baecke (r = 0.52, p = 0.01) which did not happen with the distance walked (r = 0.37, p = 0.09). Despite weight loss, patients showed no difference in the level of physical activity in any of the areas before and after surgery. Conclusion: The cardiovascular performance, the perception of effort and ability to walk seem to improve after bariatric surgery. However, despite improvement in the ability to walk by the distance achieved in the 6MWT after weight loss, this is not reflected in an increase in physical activity level of obese patients after surgery

��n��lise da capacidade funcional e da distribui����o regional da ventila����o pulmonar em pacientes com doen��a de chagas

INTRODUCTION: Cardiac and pulmonary manifestations of the Chagas disease (CD) affect between 20-30% of the infected subjects. The chronic Chagas cardiomyopathy (CCC) has some peculiarities such as arrhythmias and, especially heart failure (HF) and is potentially lethal due to left ventricular dysfunction. How respiratory disorders, patients get progressive loss of functional capacity, which contributes to a poor quality of life related to disease. Measurements of lung volume by the movement of the chest wall surface are an alternative evaluation of lung function and kinematics of complex thoracoabdominal for these patients. OBJECTIVE: evaluate the kinematics of the thoracoabdominal complex through the regional pulmonary volumes and to correlate with functional evaluation of the cardiorrespiratory system in patients with Chagas disease at rest. MATERIALS AND METHODS: a cross-section study with 42 subjects had been divided in 3 groups, 15 composed for patients with CCC, 12 patients with HF of different etiologies and 15 healthful presented control group. An optoelectronic plethysmography (POE), Minnesota questionnaire, six minute walk test, spirometer and manovacuometer was used. RESULTS: It was observed in the 6MWT where group CRL presented greater distance 464,93��44,63m versus Group HF with 399,58�� 32,1m (p=0,005) and group CCC 404��68,24m (p=0,015), both the groups presented difference statistics with regard to Group CRL. In the manovacuometer 54,59��19,98; of the group CCC and 42,11��13,52 of group IC found group CRL presented 81,31��15,25 of the predicted versus, presenting in relation to group CRL. In the POE it observed a major contribution in abdominal compartment in patients with IC if compared like CCC and control groups. On the basis of the questionnaire of quality of life of Minessota, verified a low one groups CCC and IC 43,2��15,2 and 44,4��13,1, respectively (p<0,05) when compared with the control group (19,6��17,31). CONCLUSION: it seems that the patients with CCC possess same functional and respiratory characteristics, observed for the POE, 6MWT, manovacuometer and spirometer to the patients of group HF, being able to consider similar interventions for this complementary group as therapeutical of this neglected disease

Valida����o da escala de fatigabilidade percebida para avaliação da fadiga em idosas

The term fatigability concerns the degree of fatigue associated with performing an activity of any type (physical, mental, emotional and / or social). Recently scales for assessing fatigue in the English language were created, however, gaps exist regarding the validity of these scales in relation to oxygen consumption and levels of perceived fatigue. Objective: To investigate the validity of perceived fatigability scale in older women frail and non-frail by the expired gases kinetics. Methods: This is a study of type validation, where were evaluated 48 elderly. The evaluation was conducted at two different sessions. In the first, data were collected demographic partners, as well as assessment of cognitive function, physical health, and the phenotype of frailty. The second was composed by the test 6-minute walk (6MWT) associated the expired gases kinects and assessment of perceived fatigability. Statistical analysis was performed a descriptive analysis and then we used the Pearson correlation test to evaluate the relationship between the measure of perceived fatigue and variables oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory exchange ratio (RER)before and after 6MWT. We used a linear regression model initially considering the following explanatory variable: age, Body Mass Index (BMI), presence of frailty, comorbidities, level of physical activity, distance covered in the 6MWT , the energy cost of walking and severity of fatigability on performance. Results: The final sample consisted of 44 elderly women, 4 elderly were excluded because they didn t complete all phases of this study. The mean age obtained was 75 years (�� 7.2 years). There was no significant correlation between fatigability measures and the values of VO2 ( r = .09 , p = .56 ) , VCO2 ( r = .173 , p = .26 ) , RER ( r = - .121 , p = .43 ). The final linear regression model showed that the energy cost of walking, the usual level of physical activity and the performance severity of fatigability explained 83.5 % (R2 = 0.835, p < 0.01) of the variation in the perceived fatigability. Conclusion: Our findings indicate a relationship between greater severity of fatigability and lower levels of physical activity and increased energy cost in walking, suggesting that the fatigability analyses using a simple numeric scale is valid and viable for assessment of fatigue in older women

Avaliação cl��nica e comparativa da oclus��o balanceada bilateral e desoclus��o com guia canino sobre a função mastigat��ria de usu��rios de pr��tese total remov��vel

The maintenance of masticatory function is especially important for patients who wear complete dentures due to the limitations of this type of prosthesis. Thus, the bilateral balanced occlusion (BBO) is used to achieve, besides other advantages, greater masticatory efficiency. However, analyzing critically the literature, it is observed that there is not enough scientific evidence that support the BBO as the most appropriate occlusal concept in complete dentures. This way, the purpose of the present study was to verify if complete dentures wearers with BBO present better masticatory efficiency and capacity than those with canine guidance (CG). A double-blind controlled crossover clinical trial was conducted. The sample was made of 24 completely edentulous patients. The subjects wore sets of complete dentures with both occlusal concepts for equal periods of 3 months. Objective data were collected through the masticatory efficiency test, performed by the colorimetric method, in which capsules of a synthetic material enclosing fuchsine- containing granules were used. Subjective data were recorded by patient��s ratings of their chewing function, which is the masticatory ability. No significant statistical difference was found for masticatory efficiency (p=0,0952) and masticatory ability (x2=0,5711/ p=0,4498) between the two occlusal concepts studied, as well as there was no correlation between these two variables (p=0,2985). Based on these results, it seems reasonable to use CG for the setup of complete dentures, since it is an easier and quicker technical procedure, until that future researches can come to complement this question

Avaliação gen��tica da efici��ncia reprodutiva em vacas pardo-su����as por meio da an��lise de sobreviv��ncia

Among the traits of economic importance to dairy cattle livestock those related to sexual precocity and longevity of the herd are essential to the success of the activity, because the stayability time of a cow in a herd is determined by their productive and reproductive lives. In Brazil, there are few studies about the reproductive efficiency of Swiss-Brown cows and no study was found using the methodology of survival analysis applied to this breed. Thus, in the first chapter of this study, the age at first calving from Swiss-Brown heifers was analyzed as the time until the event by the nonparametric method of Kaplan-Meier and the gamma shared frailty model, under the survival analysis methodology. Survival and hazard rate curves associated with this event were estimated and identified the influence of covariates on such time. The mean and median times at the first calving were 987.77 and 1,003 days, respectively, and significant covariates by the Log-Rank test, through Kaplan-Meier analysis, were birth season, calving year, sire (cow s father) and calving season. In the analysis by frailty model, the breeding values and the frailties of the sires (fathers) for the calving were predicted modeling the risk function of each cow as a function of the birth season as fixed covariate and sire as random covariate. The frailty followed the gamma distribution. Sires with high and positive breeding values possess high frailties, what means shorter survival time of their daughters to the event, i.e., reduction in the age at first calving of them. The second chapter aimed to evaluate the longevity of dairy cows using the nonparametric Kaplan-Meier and the Cox and Weibull proportional hazards models. It were simulated 10,000 records of the longevity trait from Brown-Swiss cows involving their respective times until the occurrence of five consecutive calvings (event), considered here as typical of a long-lived cow. The covariates considered in the database were age at first calving, herd and sire (cow s father). All covariates had influence on the longevity of cows by Log-Rank and Wilcoxon tests. The mean and median times to the occurrence of the event were 2,436.285 and 2,437 days, respectively. Sires that have higher breeding values also have a greater risk of that their daughters reach the five consecutive calvings until 84 months