7,584 research outputs found

    Use of flight interception traps of Malaise type and attractive traps for social wasps record (Vespidae: Polistinae)

    Get PDF
    The literature provides different methodologies for sampling social wasps, including, flight intercept trap type Malaise and Attractive trap, however, there is no consensus on its use. In this respect, the aim of this study was to evaluate the best use of Malaise traps and Attractive trap in biodiversity work of social wasps, and generate a collection protocol for the use of these traps. The study was conducted in the Parque Estadual do Rio Doce, located in the east of the state of Minas Gerais, in the years 2000, 2001, 2002 and 2004 and in the Botanical Garden of the Federal University of Juiz de Fora, located in the southeastern state of Minas Gerais, in years 2011, 2012 and 2013. 15 species were collected using Malaise traps, and, 26 species of social wasps were collected using Attractive traps. Although the negative aspects of both traps, complementary methodologies surveys varying social wasps are useful and it is recommended to choose for using in accordance with the logistical field

    General model for delayed feedback and its application to transimpedance amplifier's bandwidth optimization

    Get PDF
    Delays in real systems can be of two types: i) intrinsic delays - due to the physical principles of operation of each electronic device; ii) designed delays - due to extra circuits used to add the desired delay. Previous work established the possibility of achieving bandwidth improvements using small delays inside the feedback loop of feedback amplifiers. The modeling approach followed on these contributions used only one designed delay element. The bandwidth reduction effect due to intrinsic delays was not considered on these contributions. This paper extends the concept to the general case of feedback amplifiers that incorporates delays of both types. An experimental demonstration using a simple 0.35μm BiCMOS transimpedance amplifier further confirms the proposed model. © 2006 IEEE

    Assessment of Cancer-related Cognitive Impairment: Methodological Issues

    Get PDF
    Cognitive decline associated with cancer or its treatment has been addressed in many studies, though with inconsistent findings, which largely reflects the diversity of methods that have been used. In this context, we read with much interest the paper recently published in the Archives of Clinical Neuropsychology (Clapp et al., 2018) about the impact of using different reference populations on breast cancer-related cognitive impairment rates, which was based on a thorough assessment of a large number of cancer patients and non-cancer subjects

    CAMILA formal software engineering supported by functional programming

    Get PDF
    This paper describes two experiences in teaching a formal approach to software engineering at undergraduate level supported by Camila a functional programming based tool Carried on in di erent institutions each of them addresses a particular topic in the area requirement analysis and generic systems design in the rst case speci cation and implementation development in the second Camila the common framework to both experiences animates a set based language extended with a mild use of category theory which can be reasoned upon for program calculation and classi cation purposes The project a liates itself to but is not restricted to the research in exploring Functional Programming as a rapid prototyping environment for formal software models Its kernel is fully connectable to external applications and equipped with a component repository and distribution facilities The paper explains how Camila is being used in the educational practice as a tool to think with providing a kind of cross fertilization between students under standing of di erent parts of the curriculum Furthermore it helps in developing a number of engineering skills namely the ability to analyze and classify infor mation problems and models and to resort to the combined use of di erent programming frameworks in approaching them.Eje: Conferencia latinoamericana de programación funcionalRed de Universidades con Carreras en Informática (RedUNCI

    The anisotropic XY model on the inhomogeneous periodic chain

    Full text link
    The static and dynamic properties of the anisotropic XY-model (s=1/2)(s=1/2) on the inhomogeneous periodic chain, composed of NN cells with nn different exchange interactions and magnetic moments, in a transverse field h,h, are determined exactly at arbitrary temperatures. The properties are obtained by introducing the Jordan-Wigner fermionization and by reducing the problem to a diagonalization of a finite matrix of nthnth order. The quantum transitions are determined exactly by analyzing, as a function of the field, the induced magnetization 1/n\sum_{m=1}^{n}\mu_{m}\left (jj denotes the cell, mm the site within the cell, μm\mu_{m} the magnetic moment at site mm within the cell) and the spontaneous magnetization 1/nm=1n<Sj,mx,>1/n\sum_{m=1}^{n}\left< S_{j,m}^{x},\right> which is obtained from the correlations <Sj,mxSj+r,mx>\left< S_{j,m}^{x}S_{j+r,m}^{x}\right> for large spin separations. These results, which are obtained for infinite chains, correspond to an extension of the ones obtained by Tong and Zhong(\textit{Physica B} \textbf{304,}91 (2001)). The dynamic correlations, <Sj,mz(t)Sj,mz(0)>\left< S_{j,m}^{z}(t)S_{j^{\prime},m^{\prime}}^{z}(0)\right>, and the dynamic susceptibility, χqzz(ω),\chi_{q}^{zz}(\omega), are also obtained at arbitrary temperatures. Explicit results are presented in the limit T=0, where the critical behaviour occurs, for the static susceptibility χqzz(0)\chi_{q}^{zz}(0) as a function of the transverse field hh, and for the frequency dependency of dynamic susceptibility χqzz(ω)\chi_{q}^{zz}(\omega).Comment: 33 pages, 13 figures, 01 table. Revised version (minor corrections) accepted for publiction in Phys. Rev.

    Influência do sombreamento no desenvolvimento de mudas de paricá (Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby).

    Get PDF
    O presente trabalho teve como objetivo aferir a emergência de plântulas, o crescimento e o desenvolvimento de mudas de Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby aos 20, 40, 60 e 80 dias após a semeadura, submetidas aos níveis de sombreamento de 0, 30, 50 e 70%, sendo analisados os parâmetros: altura da parte aérea e diâmetro do colo. Cada tratamento foi constituído de 100 mudas com quatro repetições, por parcela e avaliadas diariamente quanto a emergência e escolhidas 15 plantas por repetição para as mensurações. Em relação às porcentagens de emergência, os resultados se apresentaram melhores no tratamento 30% de sombreamento com 95% de emergência, porém não diferiu estatisticamente dos demais tratamentos ao nível de significância de 5% pelo teste de tukey. O diâmetro do coleto foi superior a pleno sol, respondendo satisfatoriamente a ambiente com elevada intensidade luminosa. A pleno sol, as mudas foram mais vigorosas, obtiveram maior crescimento diamétrico e um maior padrão de qualidade

    Incorporation of excluded volume correlations into Poisson-Boltzmann theory

    Get PDF
    We investigate the effect of excluded volume interactions on the electrolyte distribution around a charged macroion. First, we introduce a criterion for determining when hard-core effects should be taken into account beyond standard mean field Poisson-Boltzmann (PB) theory. Next, we demonstrate that several commonly proposed local density functional approaches for excluded volume interactions cannot be used for this purpose. Instead, we employ a non-local excess free energy by using a simple constant weight approach. We compare the ion distribution and osmotic pressure predicted by this theory with Monte Carlo simulations. They agree very well for weakly developed correlations and give the correct layering effect for stronger ones. In all investigated cases our simple weighted density theory yields more realistic results than the standard PB approach, whereas all local density theories do not improve on the PB density profiles but on the contrary, deviate even more from the simulation results.Comment: 23 pages, 7 figures, 1 tabl
    corecore