All Trails Lead to Sterling: How Sterling Brown Fathered the Field of Black Literary and Cultural Studies, 1936-1969

Poet and professor Sterling A. Brown (1901-1989) played a significant role in the birth of black literary and cultural studies through his literary and academic careers. Brown helped to establish a new wave of black cultural and folklore studies during his time as the “Director of Negro Affairs” for the Federal Writers’ Project. As a professor at Howard University, Brown influenced black literary studies through his literary criticisms and seminars and his role as a mentor to literary figures of the next generations. Through letters to and from Sterling Brown and manuscripts, this thesis argues that Brown’s poetry, publications and folk studies in the nineteen twenties and thirties where the groundwork for his most prolific role of teacher-mentor

Stillbirth should be given greater priority on the global health agenda

Stillbirths are largely excluded from international measures of mortality and morbidity. Zeshan Qureshi and colleagues argue that stillbirth should be higher on the global health agenda

Measure representation and multifractal analysis of complete genomes

This paper introduces the notion of measure representation of DNA sequences. Spectral analysis and multifractal analysis are then performed on the measure representations of a large number of complete genomes. The main aim of this paper is to discuss the multifractal property of the measure representation and the classification of bacteria. From the measure representations and the values of the $D_{q}$ spectra and related $C_{q}$ curves, it is concluded that these complete genomes are not random sequences. In fact, spectral analyses performed indicate that these measure representations considered as time series, exhibit strong long-range correlation. For substrings with length K=8, the $D_{q}$ spectra of all organisms studied are multifractal-like and sufficiently smooth for the $C_{q}$ curves to be meaningful. The $C_{q}$ curves of all bacteria resemble a classical phase transition at a critical point. But the 'analogous' phase transitions of chromosomes of non-bacteria organisms are different. Apart from Chromosome 1 of {\it C. elegans}, they exhibit the shape of double-peaked specific heat function.Comment: 12 pages with 9 figures and 1 tabl

Role of serotonin transporter and receptor gene variations in the acute effects of MDMA in healthy subjects

Methylenedioxymethamphetamine (MDMA; ecstasy) is used recreationally and has been investigated as an adjunct to psychotherapy. Most acute effects of MDMA can be attributed to activation of the serotonin (5-hydroxytryptamine [5-HT]) system. Genetic variants, such as single-nucleotide polymorphisms (SNPs) and polymorphic regions in 5-HT system genes, may contribute to interindividual differences in the acute effects of MDMA. We characterized the effects of common genetic variants within selected genes that encode the 5-HT system (TPH1 [tryptophan 5-hydroxylase 1] rs1800532 and rs1799913, TPH2 [tryptophan 5-hydroxylase 2] rs7305115, HTR1A [5-HT1A receptor] rs6295, HTR1B [5-HT1B receptor] rs6296, HTR2A [5-HT2A receptor] rs6313, and SLC6A4 [serotonin transporter] 5-HTTLPR and rs25531) on the physiological and subjective response to 125 mg MDMA compared with placebo in 124 healthy subjects. Data were pooled from eight randomized, double-blind, placebo-controlled studies that were conducted in the same laboratory. TPH2 rs7305115, HTR2A rs6313, and SLC6A4 5-HTTLPR polymorphisms tended to moderately alter some effects of MDMA. However, after correcting for multiple comparisons, none of the tested genetic polymorphisms significantly influenced the response to MDMA. Variations in genes that encode key targets in the 5-HT system did not significantly influence the effects of MDMA in healthy subjects. Interindividual differences in the 5-HT system may thus play a marginal role when MDMA is used recreationally or therapeutically

Revealing the Empty-State Electronic Structure of Single-Unit-Cell FeSe/SrTiO3_{3}

We use scanning tunneling spectroscopy to investigate the filled and empty electronic states of superconducting single-unit-cell FeSe deposited on SrTiO$_3$(001). We map the momentum-space band structure by combining quasiparticle interference imaging with decay length spectroscopy. In addition to quantifying the filled-state bands, we discover a $\Gamma$-centered electron pocket 75 meV above the Fermi energy. Our density functional theory calculations show the orbital nature of empty states at $\Gamma$ and suggest that the Se height is a key tuning parameter of their energies, with broad implications for electronic properties.Comment: 5 pages, 5 figure

Cultivo intercalar de milho seguido de caupi num plantio de dendê.

bitstream/item/40157/1/Circ-Tec-47-CPATU.pd

NLO corrections in MC event generator for angular distribution of Drell-Yan lepton pair production

Using a subtraction method, we derive the formulae suitable for use in Monte-Carlo event generators to give the angular distribution for the gluon-quark induced NLO corrections in Drell-Yan lepton pair production. We also give the corresponding helicity density matrix for W and Z boson production.Comment: 14 pages, 2 figure

Buen vivir : la irrupción de América Latina en el campo gravitacional del desarrollo sostenible

Este artículo esta asociado al proyecto FONDECYT nº 1110428 (CONICYT - Chile). Una version francesa (adaptada) del presente artículo esta publicada en el número 46 de la revista Ecologie & Politique dedicado a las Ecologías políticas actuales en América Latina (Vanhulst y Beling 2013). Agradecemos cordialmente Alejandro Pelfini, Edwin Zaccaï y Joan Martinez-Alier por sus lecturas atentas y sus valiosos comentarios.En el presente artículo, proponemos una revisión del contenido del Buen vivir como discurso emergente dentro del "campo gravitacional" del desarrollo sostenible: su génesis, sus fundamentos y su singularidad. En primer lugar, consideraremos las críticas al discurso del desarrollo y a su heredero directo: el desarrollo sostenible. Luego revisaremos brevemente la posición de América Latina en el campo discursivo global del desarrollo sostenible y el lugar del Buen vivir dentro de las controversias en torno a este campo. Abrevando en el imaginario tradicional de los pueblos originarios del continente, este nuevo discurso fue teorizado en la esfera académica y traducido en principios normativos que han permeado la esfera política, lo que es visible especialmente en Ecuador y Bolivia. En este artículo nos referimos al "Buen vivir" como la reelaboración contemporánea del concepto quechua Sumak Kawsay y conceptos afines de otros pueblos autóctonos. Incluye tanto la idea de una interdependencia entre la sociedad y su medio ambiente natural como también una concepción de lo universal como realidad plural. Por último, más allá de sus implicancias para el debate medio ambiental, la propuesta del Buen vivir implica también una redefinición de las relaciones entre ciudadanía, Estado y mercado.This paper aims at reviewing the content of Buen vivir as an emergent discourse within the "gravitational field" of sustainable development: its genesis, its foundations and its singularity. First, we consider the criticisms to the development discourse and to its direct descendant: sustainable development. Next, we review the position of Latin America in the global discursive field of sustainable development and the situation of Buen vivir facing the debates therein. Drawing on the traditional repository of the aboriginal cultures of the continent, this new discourse has been theorized in the academic sphere and translated into normative principles that have permeated the political sphere, which is especially visible in the cases of Ecuador and Bolivia. In this article we refer to "Buen vivir" as the contemporary reelaboration of the quechua concept Sumak Kawsay, and other similar concepts from other indigenous nations. It includes both the idea of interdependence between society and its natural environment, as well as a conception of the universal as plural. Lastly, beyond its implications for environmental debate, Buen vivir also involves an imperative for the redefinition of relations between the citizenry, the state and the market

Proximity Driven Enhanced Magnetic Order at Ferromagnetic Insulator / Magnetic Topological Insulator Interface

Magnetic exchange driven proximity effect at a magnetic insulator / topological insulator (MI/TI) interface provides a rich playground for novel phenomena as well as a way to realize low energy dissipation quantum devices. Here we report a dramatic enhancement of proximity exchange coupling in the MI / magnetic-TI EuS / Sb$_{2-x}$V$_x$Te$_3$ hybrid heterostructure, where V doping is used to drive the TI (Sb$_{2}$Te$_3$) magnetic. We observe an artificial antiferromagnetic-like structure near the MI/TI interface, which may account for the enhanced proximity coupling. The interplay between the proximity effect and doping provides insights into controllable engineering of magnetic order using a hybrid heterostructure.Comment: 5 pages, 4 figure

Galaxy infall kinematics as a test of modified gravity

Infrared modifications of General Relativity (GR) can be revealed by comparing the mass of galaxy clusters estimated from weak lensing to that from infall kinematics. We measure the 2D galaxy velocity distribution in the cluster infall region by applying the galaxy infall kinematics (GIK) model developed by Zu and Weinberg (2013) to two suites of f(R) and Galileon modified gravity simulations. Despite having distinct screening mechanisms, namely, the Chameleon and the Vainshtein effects, the f(R) and Galileon clusters exhibit very similar deviations in their GIK profiles from GR, with ~ 100-200 k/s enhancement in the characteristic infall velocity at r=5 Mpc/h and 50-100 km/s broadening in the radial and tangential velocity dispersions across the entire infall region, for clusters with mass ~ 10^{14} Msol/h at z=0.25. These deviations are detectable via the GIK reconstruction of the redshift--space cluster-galaxy cross-correlation function, xi_cg^s(r_p,r_\pi), which shows ~ 1-2 Mpc/h increase in the characteristic line-of-sight distance r_\pi^c at r_p<6 Mpc/h from GR predictions. With overlapping deep imaging and large redshift surveys in the future, we expect that the GIK modelling of xi_cg^s, in combination with the stacked weak lensing measurements, will provide powerful diagnostics of modified gravity theories and the origin of cosmic acceleration