The DIRC Particle Identification System for the BABAR Experiment

A new type of ring-imaging Cherenkov detector is being used for hadronic particle identification in the BABAR experiment at the SLAC B Factory (PEP-II). This detector is called DIRC, an acronym for Detection of Internally Reflected Cherenkov (Light). This paper will discuss the construction, operation and performance of the BABAR DIRC in detail

NEW AND NOTEWORTHY BIRD RECORDS FROM THE EAST SLOPE OF THE ANDES OF COLOMBIA

<div>We present significant new information on the distribution and status of 138 species</div><div>of birds from the Andean East Slope of Colombia, based upon fieldwork between</div><div>1990 and 2000 at 28 sites from central Dpto. Boyacá south to the Ecuador border.</div><div>The first Colombian specimens of two species (Campylopterus villaviscensio, Napo</div><div>Sabrewing; Myrmotherula spodionota, Foothill Antwren) are reported. Three other</div><div>taxa (Ocreatus underwoodii addae, Piculus leucolaemus leucolaemus and</div><div>Myiophobus p. phoenicomitra), the first two sometimes considered species distinct</div><div>from known Colombian forms, represent first reports from Colombia based upon</div><div>sightings or photographs; we add several more sightings of two species (Pipreola</div><div>chlorolepidota, Iridisornis analis) previously known from single sight records. In</div><div>all, we report 35 species from the Andean East Slope of Colombia for the first time,</div><div>southward range extensions on this slope for 47 species, northward extensions for</div><div>21, upward or downward altitudinal extensions for 19, filling in of major discontinuities</div><div>in distribution for 22; for ten of the latter, known from very few reports, new information</div><div>indicates a continuous distribution and far greater abundance than previously</div><div>supposed. Range extensions and previously undiscovered populations of several</div><div>restricted-range, Vulnerable, Near-threatened and Threatened species help to</div><div>emphasize the importance of implementing conservation measures in the face of the increasing colonization pressures and insecurity. Based on our observations, we</div><div>present several recommendations for setting conservation priorities in this rich but</div><div>still relatively poorly known region.</div

Dispersão de sementes de uruvalheira (Platypodium elegans vog.) (Fabaceae) em um cerradão, Uberlândia-MG Seeds dispersal of uruvalheira (Platypodium elegans vog.) (Fabaceae) in cerradão, Uberlandia, MG

Estudou-se a dispersão de sementes de cinco árvores-matriz de Platypodium elegans Vog. (Fabaceae) em área de cerradão, na Estação Ecológica do Panga (EEP). As amostragens foram feitas em parcelas de 0,25 m2, posicionadas em linhas partindo da base da matriz em direção aos quatro pontos cardeais (Norte, Sul, Leste e Oeste), marcadas a cada metro. No laboratório, os frutos foram abertos para análise da qualidade das sementes. Foram amostradas 1.131 sementes, das quais 18,4% estavam intactas e 81,6%, danificadas e provavelmente inviáveis para germinação. A dispersão das sementes sofreu influência da topografia do local das matrizes, das respostas fisiológicas e genéticas à pré-dispersão, bem como do possível direcionamento favorável do vento. Dessa forma, a atuação conjunta desses fatores funcionaria como facilitadores relevantes na formação do banco de sementes e moldaria a probabilidade de estabelecimento de novos indivíduos, tanto na área estudada quanto nas fisionomias adjacentes..<br>It was studied seeds dispersal of five first trees of Platypodium elegans Vog. (Fabaceae), in area of cerradão in the Estação Ecológica do Panga (EEP). The samplings had been made in 0,25 plots of m2, located in lines leaving of the base of the matrix in direction to the four points cardinals (north, south, east and west), marked to each meter. The fruits had been opened for analysis of the quality of the seeds. A total of 1.131 seeds was collected in the sampling area of the five arrays, of which 18,4% they were viable and 81,6% probably impracticable for germination. The dispersion of the seeds suffered influence from the topography of the place of the matrices, of the physiological and genetic answers daily early-dispersion, as well as of the possible favorable aiming of the wind. The joint action of these factors serves as relevant facilitators on the seed bank training as so as the probability of establishment of new individuals both in the studied area and also in adjacent vegetation