A Discussion on Supersymmetric Cosmic Strings with Gauge-Field Mixing

In this paper, following a stream of investigation on supersymmetric gauge theories with cosmic string solutions, we contemplate the possibility of building up a D-and-F term cosmic string by means of a gauge-field mixing in connection with a U(1) x U(1)'-symmetry. The spontaneous break of both gauge symmetry and supersymmetry are thoroughly analysed and the fermion zero-modes are worked out. The role of the gauge-field mixing parameter is elucidated in connection with the string configuration that comes out. As an application of the model presented here, we propose the possibility that the supersimetric cosmic string yield production of fermionic charge carriers that may eject, at their late stages, particles that subsequently decay to produce cosmic rays of ultra-high energy. In our work, it turns out that massive supersymmetric fermionic partners may be produced for a susy breaking scale in the range 10^{11} to 10^{13} GeV, which is compatible with the phenomenology of a gravitino mass at the TeV scale. We also determine the range of the gauge-field mixing parameter, \alpha, in connection with the mass scales of the present model.Comment: 7 pages, no figures, ReVTex format, to appear in New Journal of Physic

Soil aggregation under different management systems

Considering that the soil aggregation reflects the interaction of chemical, physical and biological soil factors, the aim of this study was evaluate alterations in aggregation, in an Oxisol under no-tillage (NT) and conventional tillage (CT), since over 20 years, using as reference a native forest soil in natural state. After analysis of the soil profile (cultural profile) in areas under forest management, samples were collected from the layers 0-5, 5-10, 10-20 and 20-40 cm, with six repetitions. These samples were analyzed for the aggregate stability index (ASI), mean weighted diameter (MWD), mean geometric diameter (MGD) in the classes > 8, 8-4, 4-2, 2-1, 1-0.5, 0.5-0.25, and < 0.25 mm, and for physical properties (soil texture, water dispersible clay (WDC), flocculation index (FI) and bulk density (Bd)) and chemical properties (total organic carbon - COT, total nitrogen - N, exchangeable calcium - Ca2+, and pH). The results indicated that more intense soil preparation (M < NT < PC) resulted in a decrease in soil stability, confirmed by all stability indicators analyzed: MWD, MGD, ASI, aggregate class distribution, WDC and FI, indicating the validity of these indicators in aggregation analyses of the studied soil

Probiotics in Aquaculture Review: Current Status and Application in Tambaqui Cultivation (Colossoma macropomum)

The development of aquaculture guarantees the supply of animal protein of great nutritional value, contributing to food security. Currently one of the main problems faced is the occurrence of diseases, responsible for a worldwide economic loss, equivalent to US $ 9 billion per year. Aiming to increase resistance to diseases, increasing growth rates and food efficiency in intensive crops, some strategies have been developed, one of them is the use of probiotic bacteria. These, when in contact with the digestive tract of the host generates a series of benefits, among them, the modulation of the immune system, developing defense mechanisms and increasing resistance to stress. However, there are few documented reports on the efficiency of probiotics in native species, such as tambaqui (Colossoma macropomum). This species shows some resistance to stress, through physiological mechanisms of adaptation, such as lip expansion when subjected to hypoxia situations, which added to the positive effects of using probiotics would represent an increase in its resistance. The purpose of this work is to review the literature on the use of probiotics in aquaculture in order to provide a comprehensive synthesis of the current knowledge about its use in aquaculture, with emphasis on the intensive cultivation of tambaqui

ARANEOMORPHAE: Development of an application for the identification of the taxonomic key of arachnid families in Brazil

This study aimed to evaluate an application to support decision making in the identification process of taxonomic arachnids of families in Brazil. The device was developed by Ionic framework used to develop hybrid applications and with the help of Java Script programming language and the angular JS framework. With convenience, speed, easy handling and low cost maintenance, the digital system called for their Araneomorphae authors is an App (Application) and this digital system, professionals and lay people will perform clearly and dynamic identification and classification of specimens arachnids, reducing the time to research and understanding of their taxonomy. To review the application, a taxonomic key was used containing the figure of six Brazilian arachnids for identifying a period of 30 minutes. Were invited 200 students from five undergraduate classes in Biological Sciences from the Lutheran University Center Palmas - CEULP / ULBRA, Tocantins state for the key printed taxonomic, the vast majority of students (81%) took more than 30 minutes to identify the six species, whereas with application USAge, 91.3% of identified species of arachnids in less than five minutes. The application proved practical, easy to understand and use, and can assist in supporting decision making to identify and rank the most common early specimens of arachnids

Serological identification of virus in watermelon production fields in the Tocantins State.

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