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Atom capture and loss in ion molecule collisions
Progress is reported in measuring the energy and angular distribution of protons emerging with velocity close to the beam velocity from the target region when Ar/sup +/ beams collide with a CH/sub 4/ target and ArH/sup +/ beams collide with a He target at asymptotically high speeds. The protons result from the transfer of a target constituent to the projectile (atom capture) or from the dissociation of the projectile molecule in the collision (atom loss). For atom capture processes the Thomas peak is clearly observed. 10 refs., 3 figs
Estrogen and Progesterone Metabolites and Follicle-Stimulating Hormone in the Aged Macaque Female1
Assessment of luteal function in the vervet monkey as a means to develop a model for obesity-related reproductive phenotype
Cucumber seedling dependence on cotyledonary leaves for early growth DependĂŞncia das folhas cotiledonares para o crescimento inicial de pepino
The objective of this work was to evaluate the dependence of cucumber (Cucumis sativus L.) seedlings on cotyledonary leaves for early growth and establishment. Sets of two uniform emerging seedlings were used to quantify the initial growth and dry matter accumulation, as well as the intensity and stage of cotyledon damage in seedling establishment and to determine cotyledon protein, amino acid and carbohydrate contributions to the growing seedling. Cucumber seedling establishment was found to be highly dependent on cotyledonary leaves. Root system establishment was highly dependent on the health of the aerial part. One cotyledon was enough to maintain aerial growth of seedlings after unfolding the first true leaf. Cucumber seedlings depended on both cotyledons to keep root system growth at least until leaf area was equivalent to cotyledon area. Covering one or both cotyledons of seedlings with one unfolded leaf increased carbohydrate content of uncovered cotyledon and leaves compared with control seedlings. Cucumber seedlings are highly dependent on cotyledonary leaves and aerial parts are less dependent than root system. Cotyledon damage at early stages of plant establishment would adversely impact crop yield by reducing plant density, an important yield component, or slowing down seedling growth and establishment.<br>O objetivo deste trabalho foi estudar o desempenho das folhas cotiledonares no crescimento inicial e estabelecimento de plântulas de pepino (Cucumis sativus L.). Grupos de duas plântulas uniformemente emergidas foram utilizados para quantificar o crescimento inicial e acĂşmulo de matĂ©ria seca, o efeito da intensidade e Ă©poca de remoção dos cotilĂ©dones sobre o estabelecimento da plântula, e a contribuição de proteĂnas, aminoácidos e carboidratos dos cotilĂ©dones para o crescimento inicial. O estabelecimento das plântulas de pepino foi altamente dependente das folhas cotiledonares. As folhas cotiledonares foram fundamentais para o estabelecimento do sistema radicular. A presença de um cotilĂ©done apĂłs a emissĂŁo da primeira folha verdadeira foi suficiente para manter o crescimento da parte aĂ©rea da plântula. Plântulas de pepino foram dependentes de ambas as folhas cotiledonares para sustentar o crescimento do sistema radicular, pelo menos atĂ© a equivalĂŞncia entre área foliar e cotiledonar. A cobertura de uma ou ambas folhas cotiledonares antes da emissĂŁo da primeira folha verdadeira aumentou o conteĂşdo de carboidratos no cotilĂ©done descoberto e nas folhas, comparado com a testemunha. O crescimento inicial de plântulas de pepino Ă© altamente dependente das folhas cotiledonares, sendo a parte aĂ©rea menos dependente do que o sistema radicular. Danos nos cotilĂ©dones durante o crescimento inicial podem afetar o rendimento pela redução da densidade de plantas, um importante componente do rendimento, ou da taxa de crescimento e estabelecimento da plântula, que afeta a uniformidade da cultura