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141.
In the last decades much attention has been dedicated to the interpretation of relevant phenomena in the socio-economic field, highlighting the need of general frameworks of reference for the governance of sustainability and often recurring to the Elkington’s triple bottom line and the Etzkowitz’s triple-helix representations as reference models. In front of a massive scientific production that points out criteria and method of the model, the theory could seem less rich of applications and examples, especially in the field of the inquiry defined by sustainability. In this work, our aim is to provide a little contribution to cover this gap by (1) drawing a more general view from the triple bottom line; (2) highlighting a ‘triple-helix’ functioning in the triple bottom line as represented in the triple helix of sustainability; (3) providing an example, very actual and important, and some general reasoning related to the use of the model as a possible reference in the basic understanding of the complexity of governance for sustainability.  相似文献   
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Parvulastra exigua, a species that lacks a dispersive larva, is paradoxically one of the most widely distributed and abundant sea stars in Australia. The potential that self-fertilization and successful development of self-generated progeny might contribute to population maintenance in this species was investigated through induction of spawning in isolated individuals collected from five populations near Sydney, New South Wales (34°S, 151°E), during the spawning period (August–October 2010, 2011). Evidence of selfing differed significantly among the five populations but the level of selfing within individual egg masses did not. Overall, there was a mean of 8.9% fertilization in egg masses with embryos. Some clutches developed to the juvenile stage while others arrested development before hatching. The presence of miniscule testis tissue in gonads that appeared to be ovaries indicated that hermaphroditism may be more common in some populations than indicated by anatomy. Mixed mating (selfing + outcrossing), pseudocopulation during egg laying and developmental success of self-fertilized embryos may contribute to the ecological success of P. exigua. These might influence population genetic structure and would facilitate establishment of founder populations by a small number of migrants.  相似文献   
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A diatom data-base of 255 species obtained from 14 oceanographic cruises (14801 entries of 647 sampling sites) together with the analysis of oceanic features were used to establish four local regions in the southern Gulf of Mexico. In addition, common species for each region were designated. This study is based on the application of cluster analysis and the species frequency data. Material for this undertaking consisted of water and net samples obtained between June 1979 and December 2002. Results show that the most frequent species (> 40%) were: Asterionellopsis glacialis, Bacteriastrum delicatulum, B. hyalinum, Chaetoceros affinis, C. coarctatus, C. compresus, C. curvisetus, C. danicus, C. decipiens, C. diversus, C. lorenzianus, C. pelagicus, C. peruvianus, Coscinodiscus radiatus, Cylindrotheca closterium, Guinardia flaccida, Hemiaulus hauckii, H. membranaceus, H. sinensis, Leptocylindrus danicus, Neocalyptrella robusta, Nitzschia bicapitata, Pleurosigma diverse-striatum, Proboscia alata, Pseudo-nitzschia pungens, Pseudosolenia calcar-avis, Rhizosolenia imbricata, R. setigera, Skeletonema costatum, Thalassionema bacillare, T frauenfeldii, T nitzschioides and Thalassiosira eccentrica. The species composition for each region and season are discussed. Itis concluded that sampling site assemblages are related to oceanographic conditions. A total list of species composition is given, forty-seven species taxa being new records for this area.  相似文献   
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We describe a quantitative, rapid, sensitive and reproducible tandem mass spectrometry (MSMS) method for the one-step detection of aminoacid (AAs) and acylcarnitine (ACs) concentrations in amniotic fluid. This technology is quicker and more sensitive than other methods used to date since it is possible to determine very low AA and AC concentrations in samples simultaneously in a single run. The high degree of automation allows a large number of pregnancies to be screened for metabolic defects in a very short time. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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An experimental survey of waste tyre gasification with steam as oxidizing agent has been conducted in a continuous bench scale reactor, with the aim of studying the influence of the process temperature on the yield and the composition of the products; the tests have been performed at three different temperatures, in the range of 850–1000 °C, holding all the other operational parameters (pressure, carrier gas flow, solid residence time). The experimental results show that the process seems promising in view of obtaining a good quality syngas, indicating that a higher temperature results in a higher syngas production (86 wt%) and a lower char yield, due to an enhancement of the solid–gas phase reactions with the temperature. Higher temperatures clearly result in higher hydrogen concentrations: the hydrogen content rapidly increases, attaining values higher than 65% v/v, while methane and ethylene gradually decrease over the range of the temperatures; carbon monoxide and dioxide instead, after an initial increase, show a nearly constant concentration at 1000 °C. Furthermore, in regards to the elemental composition of the synthesis gas, as the temperature increases, the carbon content continuously decreases, while the oxygen content increases; the hydrogen, being the main component of the gas fraction and having a small atomic weight, is responsible for the progressive reduction of the gas density at higher temperature.  相似文献   
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The production of polyesters from triglyceride containing substrates was investigated. A first filter step based on lipase activity was followed and those bacteria potentially able to degrade oils or animal fats were further tested for their polymer accumulation properties, selected and kept for further studies. In a second step, bacteria were directly grown on animal fats and/or vegetable oils, and polyhydroxyalkanoates (PHAs) accumulation was verified under appropriate incubation conditions. Each substrate, whether of animal or vegetable derivation, supported the growth of a number of the newly isolated strains and among those, some strains were also found to produce reasonably high amounts of PHA. The repeat-unit composition of the polyesters was determined by gas chromatography (GC) analysis of the ?-hydroxyalkanoate methyl esters from the hydrolyzed polymer and some class of co-polymers were also detected. These properties, coupled with the ability of some of the selected isolates to grow and produce lipases on a minimal medium, could be considered as promising in view of possible industrial applications. The overall results indicate that PHAs could be produced from waste containing considerable amounts of fat, oil and grease (FOG), that generally need to be treated for their disposal.  相似文献   
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