No abstract

Hypsometric information of seedlings allows greater assertiveness of silvicultural decisions in nurseries. This study aimed to evaluate the efficiency of different Probability Density Functions (PDF) to estimate and compare the height distribution of Handroanthus heptaphyllus seedlings in different cultivation containers. One hundred and thirty one seedlings were produce in two types of containers; 81 units in tubes and the remaining in plastic bags. The census was realized at 122-day old, measuring total height of the seedlings using millimeter ruler. The seedlings did not present a tender or brittle caulinar system. Data were grouped into biometric classes with regular intervals of 2.5 cm in height. Seven PDF were adjusted using maximum likelihood method and the one with the best predictive performance was selected to identify the statistical equality between the distributions estimated for the seedling size in each container. The order of predictive efficiency of PDF was distinct between recipients. The Weibull of two parameters function can be used to model the height distribution of H. heptaphyllus seedlings at 122-day old, produced in plastic bags and tubes. The hypsometric distribution was different between containers.

This contribution is devoted to cover some technical aspects related to the use of the recently proposed energy probability distribution zeros in the study of phase transitions. This method is based on the partial knowledge of the partition function zeros and has been shown to be extremely efficient to precisely locate phase transition temperatures. It is based on an iterative method in such a way that the transition temperature can be approached at will. The iterative method will be detailed and some convergence issues that has been observed in its application to the 2D Ising model and to an artificial spin ice model will be shown, together with ways to circumvent them. arXiv:1712.04434v1 [cond-mat.stat-mech]

In this communication we explore the possible effects of statistical fluctuations on the use of the Energy Probability Distribution (EPD) zeros to study phase transitions. In the EPD zeros technique one has to find the roots of a polynomial whose coefficients are given by the EPD - a histogram of energy values obtained in a Monte Carlo simulation, for example. Phase transitions are signalized by the presence of a zero that approaches the point (1,0) in the complex plane. Once the EPD estimations are usually subject to statistical fluctuations and polynomial roots are known to be sensitive to modifications in its coefficients, we have compared the roots of a given polynomial with the roots of a perturbed one, searching for possible impacts on the method. Our results show that although the overall map of zeros is modified, the location of the dominant zero, the one that indicates the presence of a phase transition, is not affected. Indeed, even for 30% perturbation only small modifications in the dominant zero location is observed.

(93,75 e 83,33%, respectivamente) e oxidação (89,58 e 83,33 %, respectivamente). A concentração de 100% de ácido sulfúrico apresentou os melhores resultados para a desinfestação e germinação. Palavras-chave: Pau-amendoim; Semente; Escarificação química; Cultura de tecido.