179 resultados para Hooks


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Unlike Lake Victoria, the fisheries of Lake George have undergone gradual changes in the size and proportion of the major commercial fish species, the Nile tilapia (Oreochromis niloticus: cichlidae) in the last 40 years (1950-1989). The size decreased from an average weight of 900g in 1950 to 430g in 1989 while percentage contribution in commercial catches during the same period declined from 92% to 36%. The over all annual commercial catches though showed a steady increase from the period 1950 when the fishery was opened to intensive and controlled exploitation, consistently high catches were observed in the 1960s and 1970s followed by a general decline in the early 1980s to amore or less stable fishery in the late 1980s. These changes are attributed to increased fishing pressure especially on the nil tilapia and to increased use of smaller gill net mesh sizes lower than the recommended 127mm mesh. The changes in gill net mesh have brought O. leucostictus, acichlid, into commercial catches confirming that the 88.9mm mesh size nets are used by the commercial fishermen to harvest smaller fish species. The commercial catches are presently dominated by the piscivorous fishes,(over 60%) whose contribution was less than 10% during initial exploitation of the virgin fishery in 1950.The piscivorous fish are mainly caught using hooks and lines. The entire fishery is believed to be exploited close to the maximum. The above trends serve to show the impact of exploitation on fish species diversity. Quantitive and qualitative changes of the major fish species on lake George are due to exploitation pressure unlike Lake Victoria where it is a combination of both exploitations and impact of fish introductions. There has been no fish introduction in Lake George.

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Assessment of common fishery methods and of fish diversity was undertaken in two fishing camps on the Kilombero River in south-eastern Tanzania in surveys towards the end of the dry season, 1994. Fishermen identified 23 different types of fish that they caught on a regular basis. Only 19 species of fish, belonging to 17 genera and 11 families were, however, identified according to Linnean taxonomy. Hooks, nets, traps and spears were used to catch fish. Fish were either sold fresh. or preserved for storage and long-distance tranport by smoking or frying. based un frequency distributions of the numbers of fish landed over a 4 day period at one of the camps, a Shannon-diversity index of 1.95 was calculted. The fork (or total) length of 480 fish and the weight of 413 fish were measured and length frequency distributions as well as length-weight relationships determined for the six most common species. It is concluded that local fishing methods applied in the Kilombero River allow for sustainable fish production.

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现阶段对操作系统的强制访问控制框架的正确性验证的研究主要集中于对授权钩子放置的验证.文中基于TrustedBSD MAC框架对强制访问控制框架的正确性验证问题进行了研究,在授权钩子放置验证的基础上,提出了安全标记的完全初始化验证和完全销毁验证.为了实现上述验证,文中提出了一个路径敏感的、基于用户自定义检查规则的静态分析方法.该方法通过对集成于编译器的静态分析工具mygcc进行扩展来验证强制访问控制框架的钩子放置的准确性和完备性.该方法具有完全的路径覆盖性,且具有低的误报率和时间开销.

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A new species of Spionidae, Scolelepis (Scolelepis) daphoinos sp. nov., is described and illustrated from northern China seas. The species was frequently encountered and highly abundant on sand beaches, but rarely found in subtidal areas. It was formerly misidentified as S. (S.) squamata (Muller, 1806) in China but differed from the latter species in several details in morphology, including the presence of obvious reddish pigmentation patches and the absence of unidentate hooded hooks. Another two Scolelepis species, S. (S.) lingulata Imajima, 1992 and S. (S.) variegata Imajima, 1992, are reported for the first time from Chinese waters. Two species of Scolelepis, S. (S.) globosa Wu & Chen, 1964 and S. (S.) lefebvrei (Gravier, 1905), were reported previously; therefore, five species in this genus are known from China in total. A key to all Scolelepis species from Chinese waters is provided.

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Caballeria liewi Lim, 1995, uses adhesive secretions from the head organs and posterior secretory systems to assist in locomotion and attachment. Ultrastructural investigations show that the head organs of C. liewi consist of three pairs of antero-lateral pit-like openings bearing microvilli and ducts leading from two types of uninucleated gland cells (located lateral to the pharynx), one type producing rod-like (S1) bodies with an electron-dense matrix containing less electron-dense vesicles and the second type producing oval (S2) bodies with a homogeneous electron-dense matrix. Interlinking band-like structures are observed between S1 bodies and between S2 bodies. S1 body is synthesised in the granular endoplasmic reticulum, transported to a Golgi complex to be packaged into vesicles and routed into ducts for exudation. The synthesis of the S2 body is unresolved. Haptoral secretions manifested externally as net-like structures are derived from dual electron-dense (DED) secretory body produced in the peduncular gland cells. The DED body consists of a less electron-dense oval core in a homogeneous electron-dense matrix. On exocytosis into the pyriform haptoral reservoir, DED bodies are transformed into a secretion with two types of inclusions (less electron-dense oval and electron-dense spherical inclusions) in an electron-dense matrix. The secretions are further transformed (as small, oval, electron-dense bodies) when transported to the superficial anchor grooves, and on exudation into the gill tissues, the secretions become an electron-dense matrix. Secretory bodies associated with uniciliated structures, anchor sleeves and marginal hooks are also observed.

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Tese de doutoramento, Ciências do Mar, da Terra e do Ambiente (Biologia Pesqueira), Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015

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Esta dissertação tem como objetivo analisar a problemática do pensamento de mulheres negras, afro-americanas e africanas, expressamente nas suas obras selecionadas para o efeito. Pretende-se aprofundar as questões relacionadas com a problemática do racismo e das práticas de exclusão levadas a cabo por feministas brancas ocidentais perante mulheres negras e denunciadas por intelectuais negras como bell hooks, Patricia Hill Collins, Audre Lorde, feministas pós-coloniais como Uma Narayan, Chandra Talpade Mohanty e Gayatri Chakravorty Spivak e africanas, nomeadamente Molara Ogundipe-Leslie, Oyeronke Oyewumi, Chikwenye Ogunyemi, etc. No âmbito deste trabalho, dar-se-á particular relevo à questão da voz de mulheres negras, no sentido da sua capacidade de denunciar as práticas discriminatórias por parte dos feminismos ocidentais que relegaram as mulheres negras à margem da vida cultural e histórica. Analisar-se-á a razão por detrás de distanciamento de feministas negras de alguns conceitos promovidos por feminismos ocidentais e explicar-se-á a importância da insistência de mulheres negras no seu direito à auto-nomeação enquanto ato político e simbólico. O ato que leva as mulheres negras a elaborar respostas mais adequadas à realidade e às necessidades das suas conterrâneas que não são, de maneira nenhuma, idênticas às verbalizadas pelas feministas no Ocidente. Nesta dissertação de mestrado, optou-se, principalmente, por uma perspetiva cultural (na sua parte dedicada à teoria feminista, por exemplo) de forma a enquadrar a problemática da mulher africana enquanto sujeito com voz. A parte baseada em obras literárias incluída na dissertação, que apresenta dois romances de autora nigeriana da nova geração, Chimamanda Ngozi Adichie, terá como objetivo fornecer um instrumento de análise mais prático dos problemas abordados na parte inicial.

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The advent of retrievable caval filters was a game changer in the sense, that the previously irreversible act of implanting a medical device into the main venous blood stream of the body requiring careful evaluation of the pros and cons prior to execution suddenly became a "reversible" procedure where potential hazards in the late future of the patient lost most of their weight at the time of decision making. This review was designed to assess the rate of success with late retrieval of so called retrievable caval filters in order to get some indication about reasonable implant duration with respect to relatively "easy" implant removal with conventional means, i.e., catheters, hooks and lassos. A PubMed search (www.pubmed.gov) was performed with the search term "cava filter retrieval after 30 days clinical", and 20 reports between 1994 and 2013 dealing with late retrieval of caval filters were identified, covering approximately 7,000 devices with 600 removed filters. The maximal duration of implant reported is 2,599 days and the maximal implant duration of removed filters is also 2,599 days. The maximal duration reported with standard retrieval techniques, i.e., catheter, hook and/or lasso, is 475 days, whereas for the retrievals after this period more sophisticated techniques including lasers, etc. were required. The maximal implant duration for series with 100% retrieval accounts for 84 days, which is equivalent to 12 weeks or almost 3 months. We conclude that retrievable caval filters often become permanent despite the initial decision of temporary use. However, such "forgotten" retrievable devices can still be removed with a great chance of success up to three months after implantation. Conventional percutaneous removal techniques may be sufficient up to sixteen months after implantation whereas more sophisticated catheter techniques have been shown to be successful up to 83 months or more than seven years of implant duration. Tilting, migrating, or misplaced devices should be removed early on, and replaced if indicated with a device which is both, efficient and retrievable.

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Se evidenció alta selección interespecífica del espinel superficial experimental, al capturar 130 ejemplares de perico Coryphaena hippurus (87,8%) del total de 148 especímenes que incluyeron 8 especies entre peces, tortugas y cefalópodos; como pesca incidental se registró 1 enganche por lance de tortugas (verde Chelonia mydas y amarilla Caretta caretta). El anzuelo más eficiente para la captura de esta especie, fue el de menor calibre (Nº 6) que capturó 24,6%, el menos eficiente fue el Nº 5 (16,9%); sin embargo, mediante el ANOVA de dos vías se estableció que no existía efecto del tamaño de anzuelo sobre el número de ejemplares capturados (p= 0,963). Los anzuelos no evidenciaron una selección de tallas, al no establecerse diferencias significativas entre distribución de tallas (p= 0,538), excepto para los anzuelos Nº 2 y 6 (p= 0,084), al identificarse diferencia por efecto del tamaño de anzuelo. Las longitudes medias estimadas fueron 119,7 cm, 116,8 cm, 118,3 cm, 115,0 cm y 113,7 cm, para los anzuelos Nº 2, 3, 4, 5 y 6, respectivamente. El tamaño de anzuelo mostró un fuerte efecto sobre el tipo de enganche (p= 0,002), presentándose con mayor frecuencia los enganches en la agalla (53,1%) y boca (44,6%). Generalmente los enganches en la agalla son ocasionados por los anzuelos grandes (Nº 2 y 3), mientras que los de boca son realizados por los anzuelos más pequeños (Nº 5 y 6). La captura por unidad de esfuerzo (CPUE) global del longline experimental fue 1,2 ejemplares de perico para un esfuerzo de 1000 anzuelos por hora, lo que representa la tercera parte de la CPUE estimada para la flota comercial.

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This study aimed to uncover the incorporation of transformative pedagogies into the social studies curriculum. This educational approach aims to educate students about a variety of forms of oppression based on race, gender, sexuality, class, ethnicity, and culture, through the use of dialogue to uncover the students' understanding and personal experience with these concepts. This study examined the impact of discussing these topics in a grade 11 class of 22 White students (of various cultural, ethnic, and religious backgrounds). The teacher, Kelvin, and two of his students were interviewed and his class was observed on four occasions over a 2-week period. Based on the data I collected, I argue that a range of emancipatory teaching approaches should be used in critical classroom discourse. These different approaches emphasize the importance of critical thinking, the ability to recognize and combat oppression, the understanding and respect of different cultures, and the ability to recognize the impact of gender and sexuality on the past and present. These are life skills that extend beyond the curriculum (Freire, 1970; Giroux, 1988; hooks, 1994). This study fills a theory to practice gap in the research literature on transformative practice within Canadian contexts. The findings are important for several reasons. Firstly, they illustrated how the teacher's ideology and personal history affect hislher teaching and learning philosophies and approach to teaching. This has implications for the overall classroom environment, what students learn, and how teachers are trained. Secondly, this study provided a glimpse of what transformative pedagogy could look like from a pragmatic standpoint and demonstrated the complexity of using these multiple approaches in the classroom.

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Jacob Hindman (1789-1827) was an American military officer who was a captain of the Second U.S. Artillery during the War of 1812. He commanded troops at the battles at Fort George and Stony Creek in 1813, and in June of that year became the major of the Second Artillery. He remained in this position until May of 1814 when the regiment was merged with the Corps of Artillery. During the Niagara campaign in 1814, Hindman’s company commanders included Nathan Towson, Thomas Biddle, John Ritchie, and Alexander Williams. During the British attack on Fort Erie in August 1814, Hindman led an assault for which he later received a brevet promotion to lieutenant colonel for “gallant conduct in the defense of Fort Erie”. In 1815, he received an additional brevet for “meritorious services”. He is generally regarded as one of the most successful artillerists of the War of 1812. James Hall (1793-1868) served with the U.S. military as a second lieutenant in the Second Artillery during the War of 1812. He fought in the Battle of Lundy’s Lane and was General Brown’s messenger during the attack on Fort Erie. He left the military in 1818 and became a newspaper editor and author. His experiences during the War of 1812 provided material for two stories, The Bearer of Despatches and Empty Pockets. Much of his work sought to popularize the West and promote western authors.

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Receipt from Adam, Meldrum and Anderson Dry Goods and Carpets, Buffalo, New York for curtains, materials and hooks, Sept. 6, 1886.

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Receipt from M.Y. Keating, St. Catharines for picture hooks and wire, March 25, 1887.

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This study sought to explore ways to work with a group of young people through an arts-based approach to the teaching of literacy. Through the research, the author integrated her own reflexivity applying arts methods over the past decade. The author’s past experiences were strongly informed by theories such as caring theory and maternal pedagogy, which also informed the research design. The study incorporated qualitative data collection instruments comprising interviews, journals, sketches, artifacts, and teacher field notes. Data were collected by 3 student participants for the duration of the research. Study results provide educators with data on the impact of creating informal and alternative ways to teach literacy and maintain student engagement with resistant learners.

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The main objectives of the present study have been studies on the operational performance of tuna longline in Lakshadweep Sea studies on the efficiency of hooks in the longline operation studies on the efficiency of baits in the longline operation studies on bycatch in longline operation studies on predation on the longline catch and the hook loss encountered during the fishing operation