Capacity bounds for dense massive MIMO in a line-of-sight propagation environment

The use of large-scale antenna arrays grants considerable benefits in energy and spectral efficiency to wireless systems due to spatial resolution and array gain techniques. By assuming a dominant line-of-sight environment in a massive multiple-input multiple-output scenario, we derive analytical expressions for the sum-capacity. Then, we show that convenient simplifications on the sum-capacity expressions are possible when working at low and high signal-to-noise ratio regimes. Furthermore, in the case of low and high signal-to-noise ratio regimes, it is demonstrated that the Gamma probability density function can approximate the probability density function of the instantaneous channel sum-capacity as the number of served devices and base station antennas grows, respectively. A second important demonstration presented in this work is that a Gamma probability density function can also be used to approximate the probability density function of the summation of the channel's singular values as the number of devices increases. Finally, it is important to highlight that the presented framework is useful for a massive number of Internet of Things devices as we show that the transmit power of each device can be made inversely proportional to the number of base station antennas.20

A Contractor Based on Convex Interval Taylor

International audienceInterval Taylor has been proposed in the sixties by the interval analysis community for relaxing continuous non-convex constraint systems. However, it generally produces a non-convex relaxation of the solution set. A simple way to build a convex polyhedral relaxation is to select a corner of the studied domain/box as expansion point of the interval Taylor form, instead of the usual midpoint. The idea has been proposed by Neumaier to produce a sharp range of a single function andby Lin and Stadtherr to handle n × n (square) systems of equations. This paper presents an interval Newton-like operator, called X-Newton, that iteratively calls this interval convexification based on an endpoint interval Taylor. This general-purpose contractor uses no preconditioning and can handle any system of equality and inequality constraints. It uses Hansen's variant to compute the interval Taylor form and uses two opposite corners of the domain for every constraint. The X-Newton operator can be rapidly encoded, and produces good speedups in constrained global optimization and constraint satisfaction. First experiments compare X-Newton with affine arithmetic

Performance And Economic Analysis Of Finished Lambs In Feedlot

This study aimed to evaluate animal performance and economic performance of feedlot crossbred lambs (Santa Inês+ - Suffolk) fed different diets based on hay from Cynodon dactylon genotypes, through the use of financial measures considering only the period of feedlot, without relating it to the complete management cycle. A total of 30 intact crossbred Suffolk lambs, identified with earrings, with an average age of 90 days and an average body weight of 21.5 kg were used in this study. Diets were formulated using as treatments a standard concentrate and hay of the Cynodon dactylon genotypes Jiggs, Vaquero, Tifton 68, Coast-Cross, Tifton 85 and Russell in a 60:40 forage-to-concentrate ratio. The treatments were distributed in a randomized complete block design with five replicates. There were significant differences between diets in terms of total expenditure on food, and the highest values were obtained for the Jiggs genotype (BRL 48.96/animal). The animals fed diets based on Tifton 68 hay had a higher rate of return (2.16%) and profitability (34.63%) compared to the other diets. The use of diets based on Tifton 68 hay for feedlot lambs in the finishing phase brings higher economic returns compared to the remaining diets.37129330

Effects of α-tocopherol and ternatin antioxidants on morphology and activation of goat preantral follicles in vitro cultured

Os efeitos do α-tocoferol e da ternatina sobre morfologia, ativação e crescimento de folículos pré-antrais caprinos cultivados in vitro, por um ou cinco dias, foram avaliados. Os fragmentos ovarianos foram imediatamente fixados (controle não-cultivado) ou cultivados in vitro, por um ou cinco dias, em Meio Essencial Mínimo (MEM) com ou sem suplementação com α-tocoferol ou ternatina nas concentrações de 5, 10 ou 15M, formando os tratamentos MEM, TOC5, TOC10, TOC 15, TER5, TER10, TER15. O percentual de folículos pré-antrais normais no controle não-cultivado foi de 73,2%, depois de cinco dias de cultivo, houve redução desse percentual em todos os tratamentos, quando comparados com o controle não-cultivado (P<0,05). O cultivo por cinco dias aumentou a ativação folicular em todos os tratamentos (P<0,05). A análise ultra-estrutural não mostrou folículos pré-antrais íntegros após cinco dias de cultivo em meio contendo antioxidantes. Concluiu-se que o α -tocoferol e a ternatina podem promover a ativação folicular, no entanto a adição desses antioxidantes nas concentrações testadas reduziu a viabilidade folicular após o cultivo in vitro. ______________________________________________________________________________________________________________ ABSTRACTThe effects of α-tocopherol and ternatin on the morphology, activation, and growth of goat preantral follicles in vitro cultured, for one or five days, were evaluated. Ovarian fragments were immediately fixed (non-cultured control) or in vitro cultured for one or five days in Minimum Essential Medium (MEM) with or without α-tocopherol or ternatin supplementation, both at concentrations of 5, 10, or 15M, corresponding to the following treatments: MEM, TOC5, TOC10, TOC 15, TER5, TER10, and TER15. The percentages of morphologically normal preantral follicles in non-cultured ovarian tissue (control) was 73.2% and after five days of culture, there was a decrease on these percentages in all treatments (P<0.05) when compared with non-cultured control. Culture of ovarian cortex for five days increased the percentages of follicular activation in all treatments (P<0.05). Ultrastructural analysis did not confirm the integrity of caprine preantral follicles cultured for five days in medium containing antioxidants. This study demonstrated that α-tocopherol and ternatin can promote follicular activation; however, addition of these antioxidants in the tested concentrations reduced the follicular viability after in vitro culture

On the influence of a Coulomb-like potential induced by the Lorentz symmetry breaking effects on the Harmonic Oscillator

In this work, we obtain bound states for a nonrelativistic spin-half neutral particle under the influence of a Coulomb-like potential induced by the Lorentz symmetry breaking effects. We present a new possible scenario of studying the Lorentz symmetry breaking effects on a nonrelativistic quantum system defined by a fixed space-like vector field parallel to the radial direction interacting with a uniform magnetic field along the z-axis. Furthermore, we also discuss the influence of a Coulomb-like potential induced by Lorentz symmetry violation effects on the two-dimensional harmonic oscillator.Comment: 14 pages, no figure, this work has been accepted for publication in The European Physical Journal Plu

Relativistic quantum dynamics of a charged particle in cosmic string spacetime in the presence of magnetic field and scalar potential

In this paper we analyze the relativistic quantum motion of charged spin-0 and spin-1/2 particles in the presence of a uniform magnetic field and scalar potentials in the cosmic string spacetime. In order to develop this analysis, we assume that the magnetic field is parallel to the string and the scalar potentials present a cylindrical symmetry with their center on the string. Two distinct configurations for the scalar potential, $S(r)$, are considered: $(i)$ the potential proportional to the inverse of the polar distance, i.e., $S\propto1/r$, and $(ii)$ the potential proportional to this distance, i.e., $S\propto r$. The energy spectra are explicitly computed for different physical situations and presented their dependences on the magnetic field strength and scalar coupling constants.Comment: New version with 20 pages and no figure. Some minor revisions and six references added. Accepted for publication in EJP

Stress and estrous cycle affect strategy but not performance of female C57BL/6J mice

Stress induces a switch in learning strategies of male C57BL/6J mice from predominantly spatial to more stimulus-response learning. To study generalization of these findings over sex, we investigated female C57BL/6J mice at three phases of the estrous cycle under non stress and acute (10 min) restraint stress conditions. On a circular hole board (CHB) task, about half of the naive female mice used spatial and stimulus-response strategies to solve the task. Under stress, female mice favored spatial over stimulus-response strategies, with 100% of female mice in the estrus phase. Performance expressed as latency to solve the task is only improved in stressed female mice in the estrus phase. We conclude that the use of learning strategies is influenced by sex and this difference between sexes is aggravated by acute stress

Ação de fitoreguladores no desenvolvimento de Chrysanthemum leucanthemum L.

Plants of Chrysanthemum leucanthemum grown in pots with soil under greenhouse conditions, were sprayed with growth regulators twice, in May and June, to study the development of the plants in October. Succinic acid-2,2-dimethylhydrazide (SADH) at concentrations of 1250, 2500 and 5000 ppm, (2-chloroethyl) trimethylammonium chloride (CCC) 2000 ppm, (2-chloroethyl) phosphonic acid (CEPA) 320 ppm, maleic hydrazide (MH;) 1000 ppm, gibberellic acid (GA) 50 and 100 ppm, indolylacetic acid (IAA) 100 ppm, and water as check treatment, were applied. MH 1000 ppm reduced the number of leaves and stems. SADH treatments reduced the shoot growth and the number of stems. Applications of IAA 100 ppm promoted the formation of higher number of leaves and stems in Chrysanthemum leucanthemum. It was seen that sprays with GA at a concentration of 100 ppm elongated shoots.Plantas ornamentais de Chrysanthemum leucanthemum, cultivadas em recipientes contendo solo como substrato, em condições de estufa, foram pulverizadas em maio e junho com reguladores de crescimento, com a finalidade de se verificar a ação dos mesmos no desenvolvimento das plantas, determinado em outubro. Aplicaram-se SADH nas concentrações de 1250, 2500 e 5000 ppm, CCC na dosagem de 2000 ppm, CEPA 320 ppm, MH 1000 ppm, GA 50 e 100 ppm, IAA 100 ppm e água como controle. Hidrazida maleica 1000 ppm reduziu o número de folhas e hastes formadas. Tratamentos com ácido succínico - 2,2-dimetilhidrazida diminuiram a altura do caule e o número de hastes das plantas. Aplicações de ácido indolilacético 100 ppm promoveram a formação de maior número de folhas e de hastes em Chrysanthemum. Pulverizações com ácido giberélico 100 ppm incrementaram a altura do caule da espécie estudada