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ADRIAN ESPARZA 《Growth and change》1989,20(3):63-79
This paper uses a social accounting matrix (SAM) of the California economy to evaluate (1) industrial-occupational linkages associated with defense production, and (2) the relative impact of defense expenditures in a regional economy. Multipliers derived from the SAM are used to trace the distribution of wages and salaries payments from 24 industries to managerial, professional, skilled, and unskilled sectors of the labor force. Expenditures by federal defense and non-defense sectors and households are used to assess the relative impacts of defense spending in the overall regional economy. The results indicate that duality is prevalent in the regional labor market, with managerial and professional occupations receiving the greatest benefits from defense production. Overall impacts to the regional economy are less attributable to defense spending than non-defense and household sectors. 相似文献
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N. P. WILKINS H. P. COURTNEY E. GOSLING A. LINNANE C. JORDAN A. CURATOLO 《Aquaculture Research》1994,25(5):505-518
Abstract. Atlantic salmon, Salmo salar L., brown trout, S. trutta L. and their hybrids are normally identified in the field by empirical differences in maxilla length, thickness of the caudal peduncle, degree of forking of the tail and overall body conformation. This study quantifies these characters and analyses their variations in electrophoretically identified hatchery-reared individuals. Means and variances of the various measures are presented for salmon, trout and hybrids separately. The morphometric characters do not satisfactorily distinguish hybrids from the pure species, and even within samples of the pure species, some individuals will be misclassified as hybrids, or as members of the opposite species, if single characters are used on their own. Hybrids often resemble one or other parent species in one or more characters and are less often intermediate in phenotype. Triploidized hybrids are more like salmon than diploid hybrids are, and triploidized salmon are not different from diploid salmon. The results confirm that frequencies of hybrids of these species cannot be reliably assessed by morphological characters alone, and even for individuals of the pure parental species, independent confirmation of species status is advisable. Early reports of hybrid frequencies in wild stocks should be treated with caution, and apparently higher levels of hybridization in more recent studies compared with older, traditional surveys may simply reflect the greater precision of electrophoretic identification. 相似文献
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A consequence of the recent study of the mechanism of gastric secretion has been the presumption, implicit (1) if not explicit (2), that the distinctive gastric transmucosal potential has a fundamental role in the formation of hydrochloric acid. The following report indicates that the isolated surviving elasmobranch gastric mucosa does secrete acid but, unlike that of other vertebrates, does so without developing a significant epithelial potential difference. The gastric transmembrane potential is neither necessary for hydrogen ion secretion nor is its generation a fundamental feature of the mechanism that leads to the formation of hydrochloric acid. 相似文献
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ADRIAN LINNANE CHARLES JAMES JOHN MIDDLETON PETER HAWTHORNE MATTHEW HOARE 《Fisheries Oceanography》2010,19(4):290-300
Quantified estimates of southern rock lobster (Jasus edwardii) puerulus settlement have been undertaken in the Southern Zone fishery of South Australia since the early 1990s. An analysis of mean monthly puerulus settlement indices from 1995 to 2007 in three monitoring sites revealed a strong seasonal correlation (r > 0.94 between sites) in settlement patterns. Settlement was highest during the winter months of June, July and August with peak settlement in all sites occurring in July. A reduced secondary settlement occurred during February and March. Seasonal trends were correlated with monthly wind stress and direction data in order to investigate possible environmental drivers of settlement. Using monthly averages of wind stress, it was hypothesized that strong along‐shore wind‐stress anomalies (ASWSA) prior to peak settlement would influence puerulus indices. Maximum ASWSA over the December–May period prior to maximum settlement was therefore examined. The results showed significant correlations (P < 0.1, r = 0.51–0.90) between wind stress and puerulus settlement in all but one site. We suggest that storm events, in combination with onshore surface drift during the period of settlement, are the principal physical oceanographic mechanisms influencing settlement patterns within the Southern Zone rock lobster fishery of South Australia. 相似文献
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Four dogs with a history of infertility were found on examination to be azoospermic. Three of the dogs were related (a sire and two male offspring) and investigation revealed that some of their male ancestors had been of reduced fertility. There were degenerative changes in 20–40 per cent of the seminiferous tubules, a proportion of which were associated with a focal peritubular orchitis. There was a complete absence of spermatozoa in the rete testis, the vasa efferentia and the epididymis. The possibility that the condition is of an autoimmune nature is discussed. The unrelated dog had a non-inflammatory degeneration of tubules with complete absence of spermatogenesis. 相似文献
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Many pollen grains from Chenopodium quinoa plants infected with sowhane mosaic sobemovirus (SMV) were collapsed, grooved and had sunken opercula, whereas those from the first flowers of virus-free plants were smooth, rounded and with protuberant opercula. However, pollen grains from later flowers of virus-free plants were similar in appearance to those from the virus-infected plants. Similar but less obvious symptoms were found in pollen of Plantago lanccoiata infected with either ribgrass mosaic tobamovirus or broad bean wilt virus. No symptoms were found in pollen of Hordeum vulgare cv. clipper, H. sponiaitcum or Triticum acstivum infected with barley suripe mosaic hordeivirus, nor in pollen of a Cardaminc sp. naturally infected with a strain of turnip yellow mosaic tymovirus. The symptoms, even those shown by pollen from SMV-infected C quinoa, seemed not to be sufficiently characteristic for diagnosis of virus infection. 相似文献
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ABSTRACT Since the 1970s, many local jurisdictions in politically fragmented metropolitan regions have enacted growth control and management measures to tackle the challenges arising from rapid suburban growth. These locally implemented growth controls have produced spillovers—the spatial shifts of homebuilding and households to nearby localities. Using data for California, this paper investigates the link between growth controls and homebuilding. The results suggest that some of the excess homebuilding can be linked to the presence or absence of growth control measures and thus be attributed to spillover effects. Moreover, generators of spillovers are nearly exclusively located in urban areas along the coast whereas the receptors of spillovers are primarily found at the metropolitan fringes and in peripherally located jurisdictions of the interior. 相似文献
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JUAN GABRIEL BRIDA SILVIA LONDON LIONELLO PUNZO WISTON ADRIAN RISSO 《Growth and change》2011,42(3):320-350
In this paper, we study the dynamics of economic growth for 140 countries during the period 1951–2003. The variables representing economic performance are levels and growth rates of per capita gross domestic product. Using the concept of economic regime, we introduce a notion of distance between the dynamical paths of different countries. Then, a minimal spanning tree and a hierarchical tree are constructed from time series to help detect the existence of groups of countries sharing similar economic performance. The two main clusters that are identified over the whole‐time interval can be interpreted as two groups of countries with high and low performance, respectively. The evolution of such clusters shows three main stylised facts: Certain countries move across clusters; the high‐performance cluster tends to span, while the low‐performance one tends to be (more) compact; and the distance between the two groups increases in time. 相似文献
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ADRIAN STOTT TOSHIO TAKEUCHI YASUYUKI KOIKE HIROSHI YAMAKAWA OSAMU IMADA 《Fisheries Science》2002,68(5):1088-1093
Feeding artificial micro diets instead of diatoms may allow a more constant and controlled form of nutrition, and thus results in lower mortality rate and increased growth. A 4-week trial was conducted to determine the growth and survival of postlarval Haliotis discus discus (Reeve.) postlarvae fed three experimental micro particle diets, and naturally occurring diatoms. A completely randomized design was adopted with each diet being replicated three times. All diets varied in terms of particle size and gross composition. Survival rate was significantly lower ( P < 0.05) in the diatom diet (19.5 ± 2.1%) when compared with the K-1 diet (38.8 ± 8.9%), the K-2 diet (43.7 ± 5.6%) and the MD-Q diet (44.2 ± 14.8%). The size of postlarvae fed the four diets was not significantly different ( P > 0.05). There was also little difference in the daily growth rate. Based on the results of this work for the preliminary implementation of artificial food as a replacement diet for diatoms, it seems that postlarval H . discus discus readily consumes artificial micro particle diets and has a superior survival rate when compared to that of diatoms. 相似文献