878 resultados para imperial and colonial history


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Offshore geology of Pakistan is characterized by active and passive continental margins. These continental margins show very unique features such as an active Makran subduction zone in the west and the Indus delta and a submarine fan in the east. The geology of these features of Pakistan EEZ is inadequately known. This is a major obstacle in exploring mineral resources. Detailed study of coastal and shelf geology is needed for better understanding of the geology of the area and comprehensive evolution of its non-living resource potential. An understanding of the geological events including tectonic movements, sedimentation processes and geochemical history that comprise the geological history is very important to help in identification and estimation of resources. In Pakistan EEZ applying the current technology and undertaking research work to understand the seafloor features and mineral deposits associated with it will be very fruitful.

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Lakes Victoria, Kyoga and Nabugabo had a similar native fish fauna of high species diversity. stocks of most of the native species declined rapidly and some completely disappeared after Nile perch was introduced and became well established. Although, overexploitation of the fish stocks, competition between introduced and native tilapiines and environmental degradation contributed to the reduction in fish stocks, predation by the Nile perch has contributed much to the recent drastic reductions in fish stock and could even drive the stocks to a total collapse. Nile perch is also currently the most important commercial species in Lakes victoria, Kyoga and Nabugabo and the stability of its stocks is important in the overall sustainability of the fisheries of these lakes. The question that was to be examined in this paper was whether the fisheries of Lakes Victoria, Kyogaand Nabugabo would stabilize and sustain production in the presence of high predation pressure by the Nile perch or whether the Nile perch would drive the fish stocks including itself to a collapse. I t was assumed that Nile perch driven changes in Lakes Victoria, Kyoga and Nabugabo would be driven to a level beyond which they would not change further. This would be followed by recovery and stability or the changes would continue to a point of collapse. It was assumed that Lake Albert represented the ideal stable state. The changes in the new habitats expected to be driven through a major change due to Nile perch predation to a stage where there would be no further changes. After this, a feedback mechanism would move the driven variable towards recovery. The variables would then stabilize and oscillate will an amplitude which approximates to what would be recorded in Lake Albert. Alternatively, the changes would proceed to a stage where the fishery would collapse. The specific hypothesis was that fish species composition and diversity, prey selection by the Nile perch and life history characteristics of the Nile perch in the new habitats would change and stabilize

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Studies of fish and fisheries in Africa fall in to four phases: the period of fisheries expeditions, ecological investigations, the development phase, and the period of mechanized exploitation. There is need to establish the taxonomic status and ecology of the varied components of the potentially important Haplochromis in Lake Victoria. A comprehensive study of their bionomics and life history, population structure, natality, recruitment and mortality coefficients should be undertaken. Emphasis lo be laid on the study of the ecology, especially breeding behaviour of the economically important c1upeids (Stolothrissa tanganciae and Limnothrissa miodon), in Lake Tanganyika. A comprehensive investigation into the migratory and shoaling behaviour of the Lake Victoria Tilapia to be initiated. Pre-impoundment studies to be undertaken to assess effects of hydroelectric projects of fisheries. Studies on parasites of economically important fishes to be stepped up to assess pathological effects and the biological basis for their control. The role of predators, e.g., Hydrocyon, Lates and Micropterus salmoides in commercial fish populations should be evaluated, and the knowledge gaincd used to effectively manage the fisheries in favour of the more desirable fish stocks.

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Gao-Yan Li, Xu-Zhen Wang, Ya-Hui Zhao, Jie Zhang, Chun-Guang Zhang, and Shun-Ping He (2009) Speciation and phylogeography of Opsariichthys bidens (Pisces: Cypriniformes: Cyprinidae) in China: analysis of the cytochrome b gene of mtDNA from diverse populations. Zoological Studies 48(4): 569-583. The cyprinid fish Opsariichthys bidens Gunther is distributed in all major river systems of continental East Asia, and represents an attractive model for phylogeographic studies among cyprinid species or within a given species. In this study, we investigated the phylogeographic and demographic history of this species, using partial sequences of the cytochrome (cyt) b gene in mitochondrial (mt)DNA. Fish samples were collected from almost all major river systems where O. bidens is distributed in China. Sequence analysis showed remarkably high polymorphism, with 125 haplotypes in the 234 specimens examined, and with 89.8% of haplotypes occurring in only 1 specimen. A neutrality test indicated that some groups were not at mutation-drift equilibrium, suggesting a past population expansion. These results were supported by a mismatch distribution analysis. Based on our analysis, O. bidens consists of 4 groups belonging to 2 clades. The divergence time of the 2 clades was estimated to be 11.06-8.04 my. This value corresponds to the time of the 2nd uplift of the Qinghai-Tibet Plateau, the emergence of the East Asian monsoon, and the Epoch-6 Event. A two species scheme is proposed. http://zoolstud.sinica.edu.tw/Journals/48.4/569.pdf

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The evolution and variation history of the Tsushima warm current during the late Quaternary was reconstructed based on the quantitative census data of planktonic foraminiferal fauna, together with oxygen and carbon isotope records of mixed layer dweller a ruber and thermocline dweller N. dutertrei in piston core CSH1 and core DGKS9603 collected separately from the Tsushima warm current and the Kuroshio dominated area. The result showed that the Tsushima warm current vanished in the lowstand period during 40-24 cal ka BP, while the Kuroshio still flowed across the Okinawa Trough, arousing strong upwelling in the northern Trough. Meanwhile, the influence of freshwater greatly increased in the northern Okinawa Trough, as the broad East China Sea continental shelf emerged. The freshwater reached its maximum during the last glacial maximum (LGM), when the upwelling obviously weakened for the lowest sea-level and the depression of the Kuroshio. The modern Tsushima warm current began its development since 16 cal ka BP, and the impact of the Kuroshio increased in the middle and northern Okinawa Trough synchronously during the deglaciation and gradually evolved as the main water source of the Tsushima current. The modern Tsushima current finally formed at about 8.5 cal ka BP, since then the circulation structure has been relatively stable. The water of the modern Tsushima current primarily came from the Kuroshio axis. A short-term wiggle of the current occurred at about 3 cal ka BP, probably for the influences from the enhancement of the winter monsoon and the depression of the Kuroshio. The cold water masses greatly strengthened during the wiggle.

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This paper provides basic information on the general ecology and life history cycles of various flatfish species in the Bohai Sea, China. The species studied are Paralichthys olivaceus (Temminck & Schlegel), Cleisthenes herzensteini (Schmidt), Eopsetta grigorjewi (Herzenstein), Verasper variegatus (Temminck & Schlegel), Pleuronichthys cornutus (Temminck & Schlegel), Pseudopleuronectes yokohamae (Gunther), Pseudopleuronectes herzensteini (Jordan & Snyder), Kareius bicoloratus (Basilewsky), Zebrias zebra (Bloch), Cynoglossus semilaevis Gunther, Cynoglossus abbreviatus (Gray) and Cynoglossus joyneri Gunther. Information on reproduction, eggs and larval distribution, growth and adult abundance is presented. Based on the biology and ecology of these flatfish, artificial enhancement of the commercial species in the Bohai Sea is discussed.

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Objectives. To determine the prevalence of asthma symptoms among schoolchildren living on two different Brazilian Amazon islands and to identify the risk factors related to this condition. Methods. A cross-sectional study of 400 schoolchildren (5-8 years old) using written questionnaires produced by the International Study of Asthma and Allergies in Childhood, a skin prick test (allergic sensitization), and a stool examination (for helminthic infection). Nonparametric tests were carried out, and the risk factors were identified by logistic regression. Results. the prevalence of active asthma symptoms was markedly higher in children living on Outeiro Island (OI) than those living on Comb Island (CBI) (30.5% and 16.5%, respectively). the logistic regression identified several risk factors of asthma symptoms on CBI: parental history of asthma, night coughing in the past year, and currently have a cat. On OI, the major risk factors were parental history of asthma, personal history of eczema, having two or more older siblings, and night coughing in the past year. the risk factors in common on both the islands were night coughing in the past year and parental history of asthma. Conclusions. the prevalence of asthma symptoms was higher in those with a lifestyle closer to that observed in urban areas (i.e., better sanitation and hygiene), reinforcing the protective effect of a rural environment. Different risk factors were associated with asthma symptoms in schoolchildren living on OI and on CBI. This fact may reflect the environmental individuality and particularities of each island.

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Introduction: Brazil is experiencing a nutritional transition characterized by a reduction in the prevalence of nutritional deficits and an increase in overweight and obesity, not only in adults but also in children and adolescents.Objectives: This study was designed to evaluate the factors associated with overweight and obesity in Brazilian 5-year-old preschoolers.Methods: A cross-sectional study of a cohort of 232 preschoolers born in Diamantina/Minas Gerais, Brazil, was undertaken. the data, including socioeconomic status, anthropometry, diet, previous history of the preschoolers and family history, were collected between July of 2009 and July of 2010. To identify the factors associated with overweight and obesity, a logistic regression and a hierarchical model were undertaken.Results: Overweight and obesity occurred in 17.2% of the preschoolers. After adjusting for mother's obesity, per capita income, protective food intake, weight gain at age 0-4 months and time spent playing, the factors associated with overweight and obesity that reached statistical significance were mother's obesity [OR = 3.12 (95% CI 1.41-6.91), P = 0.01], weight gain of more than 0.85 kg/month in the first four months of life [OR = 2.16 (95% CI 1.01-4.64), P = 0.041 and lower per capita income [OR = 0.32 (95 %CI 0.13-0.79), P = 0.01].Conclusion: the results show that more weight gain during the first four months of life and being born of mothers with obesity increased the odds of overweight/obesity in the preschoolers, while lower per capita income was a protective factor.

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Ashmore, P. Brayshay, B.A Edwards, K.J Gilbertson, D. Grattan, J. Kent, M. Pratt, K. Weaver, R. 'Allochthonous and autochthonous mire deposits, slope instability and palaeoenvironmental investigations in the Borve Valley, Barra, Outer Hebrides, Scotland' The Holocene 2000 10, 1 pp.97-108

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Ireland Richard, 'The Felon and the Angel Copier: Criminal Identity and the Promise of Photography in Victorian England and Wales', In: Policing and War in Europe, Criminal Justice History, (Westport, CT, Greenwood Press), volume 16, pp.53-86, 2002 RAE2008

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Williams, Mike, Realist Tradition and the Limits of International Relations (Cambridge: Cambridge University Press, 2005), pp.ix+236 RAE2008

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Prescott, S. (2005). The Cambrian Muse: Welsh Identity and Hanoverian Loyalty in the Poems of Jane Brereton (1685-1740). Eighteenth -Century Studies. 38(4), pp.587-603. RAE2008

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Pearson, Mike, In Comes I: Performance, Memory and Landscape (Exeter: University of Exeter Press, 2007) RAE2008

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Rendle, M. (2005). Family, Kinship and Revolution: The Russian Nobility, 1917-1923. Family and Community History. 8(1), pp.35-47. RAE2008

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Roberts, Michael. 'Recovering a lost inheritance: the marital economy and its absence from the Prehistory of Economics in Britain', in: 'The Marital Economy in Scandinavia and Britain 1400-1900', (Eds) Argen, Maria., Erickson, Amy Louise., Farnham: Ashgate, 2005, pp.239-256 RAE2008