Atrazine (a short review of literature).

The triazines constitute a large family of herbicides. Various substitutions on the triazine basic structure yield compounds of widely different chemical and biological properties

Ensaio preliminar de sorgo granífero.

O objetivo deste trabalho foi o de testar 45 variedades de sorgo em Afrânio-PE, oriundos de uma seleção anterior realizada pelo Programa de Sorgo e Milheto-IPA-PE, em Serra Talhada. Foram incluidas 4 variedades já testadas na região, como controle, perfazendo um total de 49 repetições

Behavior of sorghum lines in relation to sugarcane borer Diatraea sacchardis (Fabricius, 1974).

Sorghum lines were evaluated for resistance to the sugarcane borer (Diatraea saccharalist) at the Afranio Research Field, Pernambuco in 1976. The infestations of the lines are given in Table 1. There was significant simple positive correlation between infestation percentage and infestation intensity (r= 0.86*). There was no correlation between infestation percentage and infestation intensity with plant height or with number and external diameter of internodes.E em Annual Plant Resistance Insects Newsletter, v.4, p.38-39, 1978

A conjugate for the Bargmann representation

In the Bargmann representation of quantum mechanics, physical states are mapped into entire functions of a complex variable z*, whereas the creation and annihilation operators $\hat{a}^\dagger$ and $\hat{a}$ play the role of multiplication and differentiation with respect to z*, respectively. In this paper we propose an alternative representation of quantum states, conjugate to the Bargmann representation, where the roles of $\hat{a}^\dagger$ and $\hat{a}$ are reversed, much like the roles of the position and momentum operators in their respective representations. We derive expressions for the inner product that maintain the usual notion of distance between states in the Hilbert space. Applications to simple systems and to the calculation of semiclassical propagators are presented.Comment: 15 page

Chromosome Segregation Is Biased by Kinetochore Size

Chromosome missegregation during mitosis or meiosis is a hallmark of cancer and the main cause of prenatal death in humans. The gain or loss of specific chromosomes is thought to be random, with cell viability being essentially determined by selection. Several established pathways including centrosome amplification, sister-chromatid cohesion defects, or a compromised spindle assembly checkpoint can lead to chromosome missegregation. However, how specific intrinsic features of the kinetochore—the critical chromosomal interface with spindle microtubules—impact chromosome segregation remains poorly understood. Here we used the unique cytological attributes of female Indian muntjac, the mammal with the lowest known chromosome number (2n = 6), to characterize and track individual chromosomes with distinct kinetochore size throughout mitosis. We show that centromere and kinetochore functional layers scale proportionally with centromere size. Measurement of intra-kinetochore distances, serial-section electron microscopy, and RNAi against key kinetochore proteins confirmed a standard structural and functional organization of the Indian muntjac kinetochores and revealed that microtubule binding capacity scales with kinetochore size. Surprisingly, we found that chromosome segregation in this species is not random. Chromosomes with larger kinetochores bi-oriented more efficiently and showed a 2-fold bias to congress to the equator in a motor-independent manner. Despite robust correction mechanisms during unperturbed mitosis, chromosomes with larger kinetochores were also strongly biased to establish erroneous merotelic attachments and missegregate during anaphase. This bias was impervious to the experimental attenuation of polar ejection forces on chromosome arms by RNAi against the chromokinesin Kif4a. Thus, kinetochore size is an important determinant of chromosome segregation fidelity

Métodos de cálculo de taxa lotação em pastagens com suplementação.

A taxa de lotação é a relação entre o número de unidades animais (UA) e a área por eles ocupada. O uso da unidade animal no cálculo da taxa de lotação tem a finalidade de padronizar o efeito das diferentes categorias animais sobre o pasto. O fornecimento de suplementação alimentar provoca distorções no cálculo da taxa de lotação. O objetivo desse trabalho foi determinar uma alternativa de cálculo de taxa de lotação para animais a pasto recebendo suplementação alimentar. A taxa de lotacão foi calculada assumindo que 1 UA corresponde a 1 animal de 454 e que 1 UA corresponde a um animal consumindo 12kg MS/dia. O consumo de forragem foi estimado pelo Corne" Net Carbohydrate and Protein System (CNCPS 3.0). Em todos os períodos, a taxa de lotação calculada a partir do peso vivo dos anímais foi mais elevada que aquela calculada com base na estimativa do consumo de matéria seca, com variações de 0,6 a 11,8 unidades de taxa de lotação. Para vacas em lactação sob pastejo, o concentrado pode representar mais de 50% do consumo total de matéria seca. Concluiu-se que o cálculo da taxa de lotação com base no peso vivo dos animais não é adequado quando os animais recebem suplementação alimentar. O cálculo da taxa de lotação a partir da estimativa do consumo de matéria seca de forragem é uma alternativa viável, porém os modelos de simulação que estimatimam consumo de matéria seca dos animais precisam ser aprimorados e validados para condições tropicais