904 resultados para Black widow spider


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Josef Molling committed suicide. He had financial problems, either embezzelment from the Prussian State Lottery or over an aircraft plant.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

left unknown child; right Peter Molling

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Elderly couple Hedwig and Ludwig Heinemann envolved with Adolph Molling Business. Younger couple is Margarete "Gretchen" Molling geb. Benjamin and Joseph Molling.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Digital Image

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Digital Image

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Wiregrasses (Aristida spp.) are becoming more prevalent, causing reduced productivity, in the black speargrass (Heterpogon contortus) pastures of south-east Queensland. Burning a native pasture of poor botanical composition (with a high proportion of wiregrass) in spring, and resting a heavily-grazed pasture also of poor composition, both improved the condition of these pastures. However, burning in late summer did not. Three months after burning in spring, relative density of wiregrass had decreased and that of a desirable species, black speargrass, had increased. However, this effect did not persist under continuous and heavy grazing. Resting increased threefold both the yield of pasture and the proportion of black speargrass, and decreased the proportion of wiregrass by two-thirds. Burning in late summer had no effect on the relative density of black speargrass but relative density of wiregrass increased. Selective grazing after burning in late summer kept this pasture in very poor condition for 14 months. These results suggest that the best way to increase the proportion of black speargrass and reduce the proportion of wiregrass in a pasture would be to burn in spring and then rest the pasture

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conceptual advances in the field of membrane transport have, in the main, utilized artificial membranes, both planar and vesicular. Systems of biological interest,viz., cells and organelles, resemble vesicles in size and geometry. Methods are, therefore, required to extend the results obtained with planar membranes to liposome systems. In this report we present an analysis of a fluorescence technique, using the divalent cation probe chlortetracycline, in small, unilamellar vesicles, for the study of divalent cation fluxes. An ion carrier (X537 A) and a pore former (alamethicin) have been studied. The rate of rise of fluorescence signal and the transmembrane ion gradient have been related to transmembrane current and potential, respectively. A second power dependence of ion conduction-including the electrically silent portion thereof — on X537 A concentration, has been observed. An exponential dependence of ldquocurrentrdquo on ldquotransmembrane potentialrdquo in the case of alamethicin is also confirmed. Possible errors in the technique are discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Digital Image

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Digital Image

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Spider venoms contain a plethora of insecticidal peptides that act on neuronal ion channels and receptors. Because of their high specificity, potency and stability, these peptides have attracted much attention as potential environmentally friendly insecticides. Although many insecticidal spider venom peptides have been isolated, the molecular target, mode of action and structure of only a small minority have been explored. Sf1a, a 46-residue peptide isolated from the venom of the tube-web spider Segesteria florentina, is insecticidal to a wide range of insects, but nontoxic to vertebrates. In order to investigate its structure and mode of action, we developed an efficient bacterial expression system for the production of Sf1a. We determined a high-resolution solution structure of Sf1a using multidimensional 3D/4D NMR spectroscopy. This revealed that Sf1a is a knottin peptide with an unusually large β-hairpin loop that accounts for a third of the peptide length. This loop is delimited by a fourth disulfide bond that is not commonly found in knottin peptides. We showed, through mutagenesis, that this large loop is functionally critical for insecticidal activity. Sf1a was further shown to be a selective inhibitor of insect voltage-gated sodium channels, consistent with its 'depressant' paralytic phenotype in insects. However, in contrast to the majority of spider-derived sodium channel toxins that function as gating modifiers via interaction with one or more of the voltage-sensor domains, Sf1a appears to act as a pore blocker.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The marketing of organically labeled prawns is predominately in a cooked or raw frozen form to avoid the development of melanosis (black spot). Certification for organic status prohibits the use of any added chemicals. The application of 60% CO2/40%N2 modified atmosphere to chilled (raw) prawns using two species of prawn was investigated for the ability to control black spot formation. Sensory assessment and microbiological counts were used to determine the end of product shelf life. Modified atmosphere packaged (MAP) prawns exhibited no melanosis for up to 16 days. The high quality life was retained for 12 days; shelf life of 16 days, according to standard microbiological criteria, was achieved, which is more than twice previously reported for non-MAP prawns. Results suggest MAP may be an effective method for the marketing of organically grown prawns as well as those produced by conventional prawn aquaculture without application of the normal chemicals used to prevent black spot. Copyright © 2014 Crown Copyright.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The colour of commercial cooked black tiger prawns (Penaeus monodon) is a key quality requirement to ensure product is not rejected in wholesale markets. The colour, due to the carotenoid astaxanthin, can be impacted by frozen storage, but changes in colour or astaxanthin profile, during frozen storage, have not been studied in detail. Subsequently in this study, the aims were to define the astaxanthin (as cis, trans, mono-ester and di-ester forms) content, together with the colour properties, in both pleopods (legs) and abdominal segments. Changes in astaxanthin content and colour properties were further determined during frozen storage (−20°C). Total astaxanthin content was seen to decrease in all samples over time, with the rate of degradation being significantly greater (P < 0.05) in pleopods than abdomen. In both pleopods and abdomen, rate of degradation of esterified forms was significantly greater (P < 0.05) than non-esterified forms. Hue angle (increase), a* value (decrease) and L value (increase) were all seen to significantly change (P < 0.05) during storage, with changes being more prevalent in the pleopods. The pleopods are the key indicator of astaxanthin and colour loss in cooked black tiger prawns and preservation strategies are required to preserve astaxanthin and colour during frozen storage.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper establishes reference ranges for hematologic and plasma biochemistry values in wild Black flying-foxes (Pteropus alecto) captured in South East Queensland, Australia. Values were found to be consistent with those of other Pteropus species. Four hundred and forty-seven animals were sampled over 12 months and significant differences were found between age, sex, reproductive and body condition cohorts in the sample population. Mean values for each cohort fell within the determined normal adult reference range, with the exception of elevated levels of alkaline phosphatase in juvenile animals. Hematologic and biochemistry parameters of injured animals showed little or no deviation from the normal reference values for minor injuries, while two animals with more severe injury or abscessation showed leucocytosis, anaemia, thrombocytosis, hyperglobulinemia and hypoalbuminemia.