Effect of Sowing Time on Phytomass Production during Early Growth of Two Varieties of \u3ci\u3eStylosanthes guianensis (Aubl.) Sw.\u3c/i\u3e

The objective of this research was to determine the effect of two sowing times on phytomass production of two varieties of Stylosanthes guianensis (var. pauciflora and var. vulgaris). Two experimental periods were studied (1: January - May/1998 and 2: November/1998 - March/1999) using a completely randomized factorial design 2 x 2 x 14 (two periods, two varieties and fourteen ages of evaluation), with four replications. The results showed a difference between the periods concerning the growth and development of Stylosanthes, and that period 2 was the most favourable to this forage plant. There was, also, different adaptability between the two varieties concerning the sowing times. The var. pauciflora was more adapted in period 1, and the var. vulgaris, in period 2. The data showed the possibility of selecting Stylosanthes cultivars adapted to different seasonal conditions

Gestão ambiental territorial do agroturismo e da agricultura orgânica.

Pela via da avaliação, adequação e gestão da qualidade ambiental na realização das atividades rurais pode-se promover a integração dos produtores, cuja organização pode culminar na gestão ambiental territorial. Conformar redes sociais de interesse, organizar agentes locais, firmar parcerias, amalgamar os anseios comunitários não são processos espontâneos, é necessária a existência de um objetivo comum, um projeto consensual para o qual convirjam os interesses desses agentes. No meio rural, as capacidades produtivas e as características dos recursos disponíveis oferecem as bases para o projeto de desenvolvimento sustentável. Tendose o objetivo acordado entre os agentes, faz-se mister elaborar um fio condutor que permita tecer a malha da rede social. O desempenho ambiental de atividades rurais oferece um tal fio condutor, averiguado, corrigido e gerido pela avaliação de impacto ambiental (AIA) em sentido amplo, integrando-se os aspectos sociais, culturais, econômicos e ecológicos. Um programa de avaliação ambiental e gestão territorial participativa foi desenvolvido para atividades de agroturismo e agricultura ecológica, respectivamente nas regiões de Itu (SP) e Venda Nova do Imigrante (ES), e Francisco Beltrão (PR) e Ibiúna (SP). Idealizou-se para esse estudo um Sistema de ?Avaliação Ponderada de Impacto Ambiental de atividades do Novo Rural? (APOIA-NovoRural), que consiste de 62 indicadores em uma plataforma de avaliação que fundamenta-se no envolvimento e no conhecimento do produtor rural quanto a seu estabelecimento, bem como em análises que indicam a situação de desempenho ambiental. Os resultados das avaliações mostraram que os indicadores da dimensão Ecologia da Paisagem são os que mais demandam intervenção para adequar a gestão dos estabelecimentos, nas atividades estudadas. O desempenho muito favorável da agricultura orgânica na dimensão Gestão e Administração foi o principal diferencial, que resultou em um desempenho melhor para essa atividade

Hydrodynamics and two-dimensional dark lump solitons for polariton superfluids

We study a two-dimensional incoherently pumped exciton-polariton condensate described by an open-dissipative Gross-Pitaevskii equation for the polariton dynamics coupled to a rate equation for the exciton density. Adopting a hydrodynamic approach, we use multiscale expansion methods to derive several models appearing in the context of shallow water waves with viscosity. In particular, we derive a Boussinesq/Benney-Luke–type equation and its far-field expansion in terms of Kadomtsev-Petviashvili-I (KP-I) equations for right- and left-going waves. From the KP-I model, we predict the existence of vorticity-free, weakly (algebraically) localized two-dimensional dark-lump solitons. We find that, in the presence of dissipation, dark lumps exhibit a lifetime three times larger than that of planar dark solitons. Direct numerical simulations show that dark lumps do exist, and their dissipative dynamics is well captured by our analytical approximation. It is also shown that lumplike and vortexlike structures can spontaneously be formed as a result of the transverse “snaking” instability of dark soliton stripes.Europe Union project AEI/FEDER: MAT2016-79866-

Efficiency of low versus high airline pressure in stunning cattle with a pneumatically powered penetrating captive bolt gun

The efficiency of stunning cattle was assessed in 443 animals (304 pure Zebu and 139 crossbred cattle), being mainly mature bulls and cows. Cattle were stunned using a Jarvis pneumatically powered penetrating captive bolt gun operating with low (160–175 psi, N = 82) and high (190 psi, N = 363) airline pressure, which was within the manufactures specifications. Signs of brain function and the position of the shots on the heads were recorded after stunning. Velocity of the captive bolt and its physical parameters were calculated. Cattle shot with low pressures showed more rhythmic respiration (27 vs. 8%, P < 0.001), less tongue protrusion (4 vs. 12%, P = 0.03) and less masseter relaxation (22 vs. 48%, P < 0.001). There was an increased frequency of shots in the ideal position when cattle were shot with the low compared to high airline pressures (15.3 vs. 3.1%). Bolt velocity and its physical parameters were significantly (P < 0.01) higher when using high pressure. Airline pressures below 190 psi are inappropriate when shooting adult Zebu beef cattle with pneumatically powered penetrating captive bolt guns

Kinematics of Black Hole X-ray Binary GRS 1915+105

The space velocity of a stellar black hole encodes the history of its formation and evolution. Here we measure the 3-dimensional motion of the microquasar GRS 1915+105, using a decade of astrometry with the NRAO Very Long Baseline Array, together with the published radial velocity. The velocity in the Galactic Plane deviates from circular rotation by 53-80 +_ 8 km/s, where the range covers any specific distance from 6-12 kpc. Perpendicular to the plane, the velocity is only 10 +_ 4 km/s. The peculiar velocity is minimized at a distance 9-10 kpc, and is then nearly in the radial direction towards the Galactic Center. We discuss mechanisms for the origin of the peculiar velocity, and conclude that it is most likely a consequence of Galactic velocity diffusion on this old binary, rather than the result of a supernova kick during the formation of the 14 Mo black hole. Finally, a brief comparison is made with 4 other BH binaries whose kinematics are well determined.Comment: 16 pages, 4 figures. ApJ accepte