Feeding of larval Cricotopus silvestris F. in relation to characters of structure of oral apparatus [Translation from: C.R.Acad.Sci.USSR.100, 1191-1193, 1955]

Laboratory research was done in order to study the feeding of larval Cricotopus silvestris F. in relation to characters of structure of oral apparatus. Results of the experiments are summarised and the oral apparatus morhologically described.

Geoquímica orgânica aplicada à formação Irati, área de Herval, Rio Grande do Sul (RS), bacia do Paraná

Esta dissertação tem por objetivo o estudo geoquímico detalhado em poço da Bacia do Paraná, mais especificamente na cidade de Herval (RS), visando preencher algumas das lacunas existentes em termos de geoquímica orgânica da Formação Irati. Com base nos dados de carbono orgânico total, enxofre total, resíduo insolúvel, raios-gama, isótopos de carbono da matéria orgânica, pirólise Rock-Eval e biomarcadores individualizaram-se dez unidades quimioestratigráficas. Biomarcadores foram usados na caracterização dos ambientes deposicionais, na discriminação da origem da matéria orgânica e da influência da litologia. O ambiente deposicional das unidades A, B, C é óxico com salinidade normal. O topo da unidade B representa a superfície de inundação máxima, onde os valores de COT aumentam. Com base nos biomarcadores caracterizou-se um paleoambiente deposicional com alguma tendência anóxica. Nas unidades D e G ocorrem os folhelhos intercalados com carbonatos. Nestas, a concentração de COT é acima de 1%, porém, somente na unidade G há bom potencial gerador para gás e condensado. As unidades E e I apresentam elevados teores de carbono orgânico total, chegando a 16%. Os dados de pirólise Rock-Eval indicam um bom a excelente potencial gerador para óleo e gás. Os dados isotópicos possibilitaram a divisão da Formação Irati, no poço em estudo, em três ciclos. O primeiro, da base para o topo, corresponde ao Membro Taquaral, os outros dois correspondem ao Membro Assistência. No Membro Assistência o δ13C varia de acordo com a salinidade, aumento da produtividade primária e da preservação da matéria orgânica (anoxia).

A database for the industrial trawl fishery of Cote d'Ivoire

Fishery statistics for the industrial trawl fishery of Cote d'Ivoire have been well documented since 1968. However, data processing has changed significantly with time and some of the data files have been lost. In 1997, the Centre de Recherches Oceanologiques d'Abidjan decided to retrieve and process all trawl data available from different sources. This paper gives an overview of the database covering the period 1968 to 1997 and describes its coverage, format, structure and use. The database was developed using MS ACCESS and is a powerful tool for storing information about this fishery, and for analysis of its dynamics over a period of 30 years.

Binding of the molecular chaperone αB-crystallin to Aβ amyloid fibrils inhibits fibril elongation.

The molecular chaperone αB-crystallin is a small heat-shock protein that is upregulated in response to a multitude of stress stimuli, and is found colocalized with Aβ amyloid fibrils in the extracellular plaques that are characteristic of Alzheimer's disease. We investigated whether this archetypical small heat-shock protein has the ability to interact with Aβ fibrils in vitro. We find that αB-crystallin binds to wild-type Aβ(42) fibrils with micromolar affinity, and also binds to fibrils formed from the E22G Arctic mutation of Aβ(42). Immunoelectron microscopy confirms that binding occurs along the entire length and ends of the fibrils. Investigations into the effect of αB-crystallin on the seeded growth of Aβ fibrils, both in solution and on the surface of a quartz crystal microbalance biosensor, reveal that the binding of αB-crystallin to seed fibrils strongly inhibits their elongation. Because the lag phase in sigmoidal fibril assembly kinetics is dominated by elongation and fragmentation rates, the chaperone mechanism identified here represents a highly effective means to inhibit fibril proliferation. Together with previous observations of αB-crystallin interaction with α-synuclein and insulin fibrils, the results suggest that this mechanism is a generic means of providing molecular chaperone protection against amyloid fibril formation.

Effects of physiological doses of vitamin D sub(3) (Cholecalciferol) on induced molting and growth in giant freshwater prawn, Macrobrachium rosenbergii (de Man)

Effects of three different doses of vitamin D sub(3) on molting, growth, and calcium and phosphate composition of tissue and molt during the grow-out of the giant freshwater prawn Macrobrachium rosenbergii (average weight 10.56 ± 0.20 g), obtained from a grow-out pond, were studied. Intramuscular doses of vitamin D sub(3) (100, 500 and 2000 IU/kg body weight) were given on the 1st, 3rd, 5th, 7th, 9th, 11th, 13th, 15th, 20th, 25th and 30th days. All the experimental animals were fed with a basal diet containing fish meal, shrimp meal, wheat flour, groundnut de-oiled cake, soybean meal and wheat bran at 3% of the body weight. The numbers of molts were recorded as 20±0.50, 29±1.16, 51±1.87, and 30±1.60 in control, 100, 500 and 2000 IU/kg body weight physiological doses, respectively. Maximum growth was recorded in prawns given 500 IU/ kg dose. Survival was between 58.33 ± 9.13 and 77.77 ± 8.61%. The ash content and calcium level increased significantly (p<0.05) and recorded the highest values in 500 IU/kg physiological dose. However, the inorganic phosphate (P sub(i)) content recorded the highest values in tissue in 2000 IU/kg dose (p<0.05, F = 50.60613). There is no significant difference in calcium contents (p>0.05) in both tissue and molt at 500 and 2000 IU/kg doses. It was found that a higher physiological dose (2000 IU/kg) of vitamin D sub(3) increased the rate of mortality. Results have shown that vitamin D sub(3) has a positive impact on the growth and survival of M. rosenbergii and it interferes with the metabolism of Ca and P sub(i), in tissue, and alters molting frequency. Results on physiological dose suggest an alternative and effective dietary supplementation method of vitamin D sub(3) in the grow-out phase of M. rosenbergii.