Individual and trophic efficiencies of size-structured communities are derived from mechanistically based principles at the individual level. The derivations are relevant for communities with a size-based trophic structure, i.e. where trophic level is strongly correlated with individual size as in many aquatic systems. The derivations are used to link Lindeman's trophic theory and trophic theor...

Growth, age and somatic production of the benthic predator Adelomelon brasiliana were studied at the southern limit of its distribution on the South AmericanAtlantic shelf. Stable oxygen isotope ratios confirmed annual formation of internal shell growth marks. Modal shell length of the population was 140 mm, while modal shell-free wet mass was 255 g. A logistics growth function (SL¥=186.28 mm, ...

We develop a model for somatic growth in fishes that explicitly allows for the energy demand imposed by reproduction. We show that the von Bertalanffy (VB) equation provides a good description of somatic growth after maturity, but not before. We show that the parameters of the VB equation are simple functions of age at maturity and reproductive investment. We use this model to show how the ener...

BACKGROUND Few longitudinal studies describe the relationship between somatic symptoms and family disagreements. We examined changes over time in somatic symptoms, family disagreements, their interrelationships, and whether these patterns differed between individuals treated for depression (depression group) and individuals from the same community (community group). METHODS We followed partic...

Cork oak (Quercus suber L.) is one of the most important Mediterranean forest tree species, and Maâmora forest-Morocco considered to be world largest cork stand. Clonal propagation Quercus via somatic embryogenesis an alternative conventional methods. However, complete maturation embryos major bottleneck for mass during embryogenesis. This study focuses on influences cytokinins secondary Cytoki...

The developmental pathway of somatic embryogenesis in Norway spruce involves proliferation of proembryogenic masses (PEMs), PEM-to-somatic embryo transition and further development of the somatic embryos. It has previously been shown that extracellular signal molecules, including arabinogalactan proteins, lipo-chitooligosaccharides and chitinases, regulate somatic embryogenesis. The Chia4-Pa1 g...

this study was carried out to investigate the morphological and anatomical aspects of somatic embryogenesis in date palm. lateral bud and shoot tip explants excised from young offshoots were cultured on ms medium with 2,4-d. somatic embryogenesis was in-duced by transferring the calli produced on the same medium without hormones. micro-tome sectioning of paraffin-embedded specimens was carried ...