Aumento da percepção ambiental das populações: estratégia adotada pela Embrapa Solos.

bitstream/CNPS-2010/14945/1/circ-tec-2006-percepcao-ambiental.pd

Quantifying the Drivers of Star Formation on Galactic Scales. I. The Small Magellanic Cloud

We use the star formation history of the Small Magellanic Cloud (SMC) to place quantitative limits on the effect of tidal interactions and gas infall on the star formation and chemical enrichment history of the SMC. The coincident timing of two recent (< 4 Gyr) increases in the star formation rate and SMC/Milky Way(MW) pericenter passages suggests that global star formation in the SMC is driven at least in part by tidal forces due to the MW. The Large Magellanic Cloud (LMC) is the other potential driver of star formation, but is only near the SMC during the most recent burst. The poorly constrained LMC-SMC orbit is our principal uncertainty. To explore the correspondence between bursts and MW pericenter passages further, we model star formation in the SMC using a combination of continuous and tidally-triggered star formation. The behavior of the tidally-triggered mode is a strong inverse function of the SMC-MW separation (preferred behavior ~ r^-5, resulting in a factor of ~100 difference in the rate of tidally-triggered star formation at pericenter and apocenter). Despite the success of these closed-box evolutionary models in reproducing the recent SMC star formation history and current chemical abundance, they have some systematic shortcomings that are remedied by postulating that a sizable infall event (~ 50% of the total gas mass) occured about 4 Gyr ago. Regardless of whether this infall event is included, the fraction of stars in the SMC that formed via a tidally triggered mode is > 10% and could be as large as 70%.Comment: Accepted for publication in Ap

Relação entre o intervalo de partos e o custo total de produção de leite por vaca no rebanho.

O intervalo de partos foi a variavel de maior impacto nos custos de producao de vacas da raca holandesa de primeira e segunda lactacoes, seguida da producao total de leite. A idade ao primeiro parto e o valor genetico relacionaram-se apenas com o custo de producao de vacas holandesas de primeira lactacao. No caso de vacas mesticas (HZ) de primeira e segunda lactacao apenas o intervalo de partos e a producao total de leite relacionaram-se com o custo total.Resumo expandido

Crescimento corporal e sistema digestivo em frangos de corte.

Foram analisados dados do peso corporal e do sistema digestivo em função da idade em frangos de corte de linhagem Pilch, de um a 70 dias de idade

Barragem subterrânea: água para uso na agricultura.

Introdução; Considerações gerais e recomendações técnicas; Benefícios e cuidados no uso da tecnologia.bitstream/item/17368/1/Barbosa.pd

Balanço energético e proteico de rações para suínos machos, inteiros e castrados, de diferentes raças e pesos.

Determinar o efeito do sexo( animais inteiros e castrados) da raça(Landrace, Large white e cruza landrace X large white) e dos pesos ou períodos sobre o balanço energético e proteico de uma ração que tinha por base milho e farelo de soja para suínos

Effect of abscisic acid on the calcium content for controlling blossom-end rot in tomato under water stress.

Water stress in tomato plants may cause the incidence of blossom-end rot. This study aimed to analyze the effect of abscisic acid leaf application for increasing the calcium uptake in irrigated tomato (?Santa Clara? cultivar) in the field, as a possible mechanism of blossom-end rot inhibition. The treatments consisted of four irrigation levels (25 %, 50 %, 75 % and 100 % of the crop water requirements to fulfil the crop evapotranspiration) and two abscisic acid doses (0 mg L-1 and 500 mg L-1). The fruits were harvested at 15 and 30 days after the anthesis and evaluated for calcium content and percentage of blossom-end rot. The application of abscisic acid increased the calcium partition to the distal region of the fruits at 30 days after the beginning of flowering, as well as reduced the incidence of blossom-end rot by 86 %, when compared with plants not treated with abscisic acid. It is possible to conclude that the foliar application of abscisic acid can significantly reduce the incidence of blossom-end rot

Abscisic acid on the quality of tomato fruits.

The use of abscisic acid (ABA) in agriculture has increased in the last few years due to the increase in ABA commercial availability at lower costs. The objective of this study was to determine the effect of exogenous ABA on tomato fruit quality parameters such as soluble solids (SS), total and soluble pectins, titratable acidity (TA) and flesh firmness. Tomatoes from the cultivar ?Santa Clara? were the study followed a complete randomized block desig, with four treatments in five repetitions. The treatments were plants not treated with ABA (control), foliar sprayed with ABA at 500 mg L -1, 150 mLdrench with ABA at 500 mg L-1, or foliar plus drench treated with ABA. After harvesting, the physicochemical characteristics of the fruits were evaluated in the laboratory. All treatments were weekly applied to the plants from anthesis to harvest at fully maturity. Root treatment increased SS by up to 26.12%, increased ratio SS/TA, firmness and decreased soluble pectin. According to the results, it can be concluded that the application of ABA to leaves and roots can improve fruit quality by increasing the SS, ratio SS/TA. The method of application affects the SS content