70 research outputs found
Desempenho do cultivo da berinjela em plantio direto submetida a diferentes lâminas de irrigação.
Este estudo foi conduzido no município de Seropédica, RJ, com o objetivo de se determinar, em cultivo
orgânico e sistema de plantio direto, a produtividade da cultura da berinjela sob diferentes lâminas de
irrigação e sistemas de cultivo (consorciada com leguminosa e solteira). O delineamento experimental
adotado foi o de blocos ao acaso, no esquema de parcela subdividida com quatro repetições
caracterizando, na parcela, os tratamentos equivalentes à lâmina de irrigação (40; 70; 100 e 120% ETc)
e, na subparcela, os sistemas de cultivo consorciado com feijão caupi e solteiro. Ambos os sistemas de
cultivo não influenciaram a produtividade final da berinjela; no entanto, considerando as diferentes
lâminas, a maior produtividade comercial foi de 65,41 Mg ha-1, obtida para uma lâmina total de 690,04
mm (106,8% ETc). A menor lâmina aplicada resultou em qualidade inferior dos frutos em relação às
maiores lâminas, sendo a taxa de descarte dos frutos de 3 e 14%, respectivamente, para a maior e a
menor lâmina
Prevalence, incidence and distribution of citrus variegated chlorosis in Bahia, Brazil
Citrus variegated chlorosis (CVC) is one of the most important diseases for Brazilian citriculture. It is caused by Xylella fastidiosa subsp. pauca, a xylem limited, cycadelid and budwood transmitted bacterium. In Bahia, the second most important citrus region in Brazil, CVC has been present since 1997. Our objectives were to characterize the regional spatial pattern of CVC and to establish a relationship between epidemiological variables and horticultural practices, as well as to evaluate whether control measures used so far have been effective and, based on that, to conceive suitable control measures. A series of surveys were performed in two regions of Bahia State (Recôncavo Baiano and Litoral Norte), along with a survey of horticultural and control practices associated with sampled groves. CVC was restricted to Litoral Norte region, especially to three municipalities along the border between Bahia and Sergipe States. The mean CVC incidence in these municipalities followed a gradient, higher in the countryside and decreasing along the coast. Presence and dissemination of CVC was related to poor nursery practices, a massive use of a susceptible orange variety, and an extreme concentration of orange groves in high incidence municipalities, as well as to the absence of specific CVC control. Considering that CVC was not found in Recôncavo Baiano, this region could be considered a "CVC free zone" by the local government. Copyright by the Brazilian Phytopathological Society.EC/ICA4-CT-2001-10005CNPqFAPES
Eggplant crop in no tillage system under different irrigation depths
Este estudo foi conduzido no município de Seropédica, RJ, com o objetivo de se determinar, em cultivo orgânico e sistema de plantio direto, a produtividade da cultura da berinjela sob diferentes lâminas de irrigação e sistemas de cultivo (consorciada com leguminosa e solteira). O delineamento experimental adotado foi o de blocos ao acaso, no esquema de parcela subdividida com quatro repetições caracterizando, na parcela, os tratamentos equivalentes à lâmina de irrigação (40; 70; 100 e 120% ETc) e, na subparcela, os sistemas de cultivo consorciado com feijão caupi e solteiro. Ambos os sistemas de cultivo não influenciaram a produtividade final da berinjela; no entanto, considerando as diferentes lâminas, a maior produtividade comercial foi de 65,41 Mg ha-1, obtida para uma lâmina total de 690,04 mm (106,8% ETc). A menor lâmina aplicada resultou em qualidade inferior dos frutos em relação às maiores lâminas, sendo a taxa de descarte dos frutos de 3 e 14%, respectivamente, para a maior e a menor lâmina.This study was carried out in the municipality of Seropedica-RJ, in order to determine, under organic farming and no tillage system, the yield of eggplants under different irrigation depths and cropping systems (intercropped with legumes and alone). The experimental design was in randomized blocks in a split plot design with four replications. The plots were characterized by the treatments corresponding to different water depths (40, 70, 100, 120% ETc), and the sub plots, the intercropping systems with cowpea and eggplant alone. Cropping systems did not influence the final yield of eggplant. However, considering the different irrigation depths, the highest commercial yield (65.41 Mg ha(-1)) was obtained for a total depth of 690.04 mm (106.8% ETc). The lower applied depth provided lower quality of fruit compared with that observed in the higher depths. The rate of fruit discard was 3 and 14%, respectively, for the higher and lower depths of irrigation
Luminescence tuning of MOFs via ligand to metal and metal to metal energy transfer by co-doping of 2∞[Gd2Cl6(bipy)3]*2bipy with europium and terbium
The series of anhydrous lanthanide chlorides LnCl3, Ln=Pr–Tb, and 4,4'-bipyridine (bipy) constitute isotypic MOFs of the formula 2∞[Ln2Cl6(bipy)3]*2bipy. The europium and terbium containing compounds both exhibit luminescence of the referring trivalent lanthanide ions, giving a red luminescence for Eu3+ and a green luminescence for Tb3+ triggered by an efficient antenna effect of the 4,4'-bipyridine linkers. Mixing of different lanthanides in one MOF structure was undertaken to investigate the potential of this MOF system for colour tuning of the luminescence. Based on the gadolinium containing compound, co-doping with different amounts of europium and terbium proves successful and yields solid solutions of the formula 2∞[Gd2-x-yEuxTbyCl6(bipy)3]*2bipy (1–8), 0≤x, y≤0.5. The series of MOFs exhibits the opportunity of tuning the emission colour in-between green and red. Depending on the atomic ratio Gd:Eu:Tb, the yellow region was covered for the first time for an oxygen/carboxylate-free MOF system. In addition to a ligand to metal energy transfer (LMET) from the lowest ligand-centered triplet state of 4,4'-bipyridine, a metal to metal energy transfer (MMET) between 4f-levels from Tb3+ to Eu3+ is as well vital for the emission colour. However, no involvement of Gd3+ in energy transfers is observed rendering it a suitable host lattice ion and connectivity centre for diluting the other two rare earth ions in the solid state. The materials retain their luminescence during activation of the MOFs for microporosity
Stress and breast cancer: from epidemiology to molecular biology
Stress exposure has been proposed to contribute to the etiology of breast cancer. However, the validity of this assertion and the possible mechanisms involved are not well established. Epidemiologic studies differ in their assessment of the relative contribution of stress to breast cancer risk, while physiological studies propose a clear connection but lack the knowledge of intracellular pathways involved. The present review aims to consolidate the findings from different fields of research (including epidemiology, physiology, and molecular biology) in order to present a comprehensive picture of what we know to date about the role of stress in breast cancer development
Coeficientes da equação de Angström-Prescott e sua influência na evapotranspiração de referência em Seropédica, RJ
Lawson criterion for ignition exceeded in an inertial fusion experiment
For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion
Underlying Event measurements in pp collisions at and 7 TeV with the ALICE experiment at the LHC
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