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Witold L. Klawe 《Ocean Development & International Law》2013,44(1):37-64
Abstract Annual catches of pelagic organisms, excluding marine mammals, from the Atlantic and Pacific waters surrounding the Americas for the period 1969–1971 averaged 17, 000, 000 metric tons. Catches of the pelagic organisms from the Pacific alone were nearly 14, 000, 000 tons. However, considering the recent drop in the catches of the Peruvian anchovy, the data for 1972 and 1973 when compiled, will show a drastic decline in the catches of pelagic species. Catches from American waters are compared with those from other waters and their relationship to the area and population of the Americas is examined. The potential maximum catch of pelagic organisms currently utilized is projected to 26, 000, 000 tons, whereas if the markets and fishing technology could be developed for non‐conventional species, then it is estimated that the catch could be increased to 42, 000, 000 tons. Rational utilization of the pelagic resources of the Americas necessitates conservational and managerial measures. This in turn calls for international agreements and/or other international arrangements. This paper was presented at the Inter‐American meeting on “Science and Man in the Americas”; in 1973 at Mexico City. 相似文献
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Stanisław Han Katarzyna Karłowicz-Bodalska Piotr Potaczek Adam Wójcik Łukasz Ozimek Dorota Szura Witold Musiał 《AAPS PharmSciTech》2014,15(1):111-120
The identification of new contaminants is critical in the development of new medicinal products. Many impurities, such as pentanedioic acid, hexanedioic acid, heptanedioic acid, octanedioic acid, decanedioic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, and tetradecanedioic acid, have been identified in samples of azelaic acid. The aim of this study was to identify impurities observed during the stability tests of a new liposomal dosage form of azelaic acid that is composed of phosphatidylcholine and a mixture of ethyl alcohol and water, using high-performance liquid chromatography with evaporative light-scattering detector (HPLC-ELSD), gas chromatography–flame ionisation detection (GC-FID), and gas chromatography–mass spectrometry (GC-MS) methods. During the research and development of a new liposomal formulation of azelaic acid, we developed a method for determining the contamination of azelaic acid using HPLC-ELSD. During our analytical tests, we identified a previously unknown impurity of a liposomal preparation of azelaic acid that appeared in the liposomal formulation of azelaic acid during preliminary stability studies. The procedure led to the conclusion that the impurity was caused by the reaction of azelaic acid with one of the excipients that was applied in the product. The impurity was finally identified as an ethyl monoester of azelaic acid. The identification procedure of this compound was carried out in a series of experiments comparing the chromatograms that were obtained via the following chromatographic methods: HPLC-ELSD, GC-FID, and GC-MS. The final identification of the compound was carried out by GC with MS. 相似文献
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Experimental trails run off natural field trails of Iridomyrmex humilis have been used to demonstrate the range of exocrine glands involved in trailing behaviour. Complex trailing reactions were recorded by high-speed movie photography, and their interactions were assessed by multivariate analysis. Pavan's gland is confirmed as the source of major trailing pheromone(s) deposited on the substrate, which act as strong, persistent attractants and activators. The mandibular glands produce volatile, transient behavioural signals in air; the anals produce anti-trailants; and the pharyngeals and venoms may possibly be implicated as the producers of trailing synergists. The findings for I. humilis are considered in relation to the evolution of trailing behaviour through the Formicidae. 相似文献
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L. Anne Zaleski Joseph Dancis Rody P. Cox Joel Hutzler Witold A. Zaleski Alan Hill 《CMAJ》1973,109(4):299-304
Intermittent MSUD in a mother and her daughter is reported. Fibroblast cultures were studied for branched-chain keto acid decarboxylase and results show that the mother has approximately 12% while the daughter has 5% of the normal enzyme activity. Other key members in the family were also studied for enzyme activity. It appears that the child has inherited an abnormal gene from her homozygous mother and another abnormal gene from her heterozygous father.A classification based on the degree of residual enzyme activity and protein tolerance places the mother in grade III and the daughter in grade II category. Classical MSUD, where the enzyme activity is less than 2% of normal, belongs to grade I. 相似文献