996 resultados para Clark, John


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Difficulties concerning the taxonomy of stauromedusae are long known, and there is a clear need for taxonomic revision of the genus Haliclystus, as well as the reevaluation of some species. Haliclystus antarcticus Pfeffer, 1889 is recorded from Admiralty Bay, King George Island, Antarctic Peninsula. Due to the lack of detailed information on this species, we provide a redescription, presenting new data on the cnidome, morphometry, geographical distribution and intraspecific variation. Based on these characters, we propose that our specimens and Haliclystus auricula from Chile and Argentina are synonymous and should be classified as H. antarcticus. We also review the worldwide distribution of the genus Haliclystus Clark, 1863 and discuss taxonomic issues, concluding that some characters traditionally used in the taxonomy of the group should be used cautiously.

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Syftet med denna uppsats är att undersöka hur och med vilka medel det skrämmande i John Ajvide Lindqvists Låt den rätte komma in skapas, hur detta förmedlas till läsaren och vilka konsekvenser detta får samt att undersöka på vilket sätt vampyren Eli skiljer sig från den traditionella vampyren.Utgångspunkt i romanen är den mänskliga kroppen och särskilt fokus läggs vid kroppsvätskor, kroppslukter, det sexuellt avvikande och den deformerade kroppen. Gestaltningen av detta handlar om ett brytande mot tabun och etablerade normer som finns i vårt samhälle i dag. Detta skapar känslor av obehag och äckel hos läsaren. Ajvide Lindqvist använder sig av det groteska i syfte att illustrera de obekvämligheter som vi inte vill kännas vid.Eli skiljer sig från den traditionella vampyren genom att vara ett barn och genom att kunna uppfattas som flicka. Här finns också en komplexitet vad gäller kön, då Eli kan sägas vara intergender – av ett odefinierbart kön som ligger bortom de vanliga kategorierna "man" och "kvinna".

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If John Martyn Harlow is known at all in the neurosciences, it is because he was the physician who attended Phineas Gage and followed up his case. Although Harlow's brief but insightful accounts of the changes in Gage's personality are fairly well recognized, and his skill in treating Gage often acknowledged, Harlow himself is, for the most part, the shadowy figure caught by the self-depreciatory characterization of the subtitle of this paper. Although his contribution to the neurosciences was singular, literally and figuratively, he deserves a place in the history of the subject. Harlow's training in antiphlogistic therapy can be seen in his treatment of Gage and in his evaluation of its results. As a medical student, he was also exposed to phrenological doctrine, the influence of which can also be seen in his  appreciation and explanation of some aspects of Gage's behaviour.  Manuscript materials, newspaper reports, and other little known material are used here to evaluate Harlow's contributions to medicine and to the medical, political, and civic life of Cavendish, Woburn, and the Commonwealth of Massachusetts.

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A blue strain of the yabby Cherax destructor albidus was compared to two normal-coloured strains of C. d. destructor and C. d. albidus for brood size and juvenile weight. Reproductive performance of the blue strain was found to be significantly poorer than the two normal-coloured strains. Similarly, the weight of newly independent juveniles was also found to be significantly lower for the blue strain. No differences were detected between the two normal-coloured strains in either reproductive performance or size of newly independent juveniles. The phenotypic differences between the blue strain and normal-coloured strains are most likely genetic. However, further studies are needed to investigate whether these differences are due to pleiotropy or inbreeding effects.

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Non-coding copies of fragments of the mitochondrial genome translocated to the nucleus or pseudogenes are being found with increasing frequency in a diversity of organisms. As part of a study to evaluate the utility of a range of mitochondrial gene regions for population genetic and systematic studies of the Australian freshwater crayfish, Cherax destructor (the yabby), we report the first detection of Cytochrome b (Cyt b) pseudogenes in crustaceans. We amplified and sequenced fragments of the mitochondrial Cyt b gene from 14 individuals of C. destructor using polymerase chain reaction (PCR) with primers designed from conserved regions of Penaeus monodon and Drosophila melanogaster mitochondrial genomes. The phylogenetic tree produced from the amplified fragments using these primers showed a very different topology to the trees obtained from sequences from three other mitochondrial genes, suggesting one or more nuclear pseudogenes have been amplified. Supporting this conclusion, two highly divergent sequences were isolated from each of two single individuals, and a 2 base pair (bp) deletion in one sequence was observed. There was no evidence to support inadvertent amplification of parasite DNA or contamination of samples from other sources. These results add to other recent observations of pseudogenes suggesting the frequent transfer of mitochondrial DNA (mtDNA) genes to the nucleus and reinforces the necessity of great care in interpreting PCR-generated Cyt b sequences used in population or evolutionary studies in freshwater crayfish and crustaceans more generally.

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Juvenile Cherax destructor (commonly called the yabby) (mean weight 48.3 mg) were cultured intensively (stocking density 360/m2) under controlled conditions for 48 days. The animals were provided with a combination of food (high protein pellets and/or natural feed organisms attached to a conditioned synthetic substrate) and refuge. Fastest growth and highest yield was recorded when both pellets and the conditioned synthetic material were provided. Although the yabbies sheltered in the synthetic substrate, it did not increase survival. Juvenile yabbies (< 200 mg) were able to graze on small organisms attached to the synthetic material but this ability appeared to decline as the yabbies grew to a larger size. The use of artificial substrates in the intensive nursery phase production of juvenile freshwater crayfish is discussed.

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Feyerabend, 1975; Feyerabend, 1981 and Feyerabend, 1987 takes J. S. Mill’s On Liberty to support the proliferation of theories in science and to emphasize the fallibility of scientific knowledge. On Liberty, according to Feyerabend, contradicts and overthrows Mill’s major study of science, A System of Logic. Staley (1999) reads the 2 works of Mill as giving complementary accounts of science. The present author rejects these interpretations of Mill, arguing that A System of Logic and On Liberty are mutually compatible since On Liberty concerns the nature of non-scientific knowledge and the methods that Mill believes are appropriate to expanding and assessing that knowledge.

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Inheritance of three kinds of molecular genetic markers (mtDNA, random-amplified polymorphic DNAs (RAPDs) and allozymes) and sex were investigated in crossbreeding experiments between three populations of the Australian freshwater crayfish Cherax destructor. Crossbreeding did not disrupt the ively maternally inherited, and allozyme and RAPD markers were transmitted following expected Mendelian principles for co-dominant and dominant traits respectively. Unlike these three markers, sex ratios were found to be distorted by crossbreeding in some families. Two crossbred families produced only females. The implications of these findings for freshwater crayfish population genetics, taxonomy and aquaculture are discussed.


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In July 2003 an important one-volume text, Forget about Flinders: A Yanyuwa atlas of the south west gulf of Carpentaria produced in a limited edition of 14 copies, returned to Yanyuwa country and to the families who collaborated with John Bradley and artist Nona Cameron on the project. Subsequently, a second edition of 20 copies has been released, mainly to institutions. It is the most comprehensive attempt yet to restore Yanyuwa names to country and to produce a multilayered, dynamic, history-rich, and bilingual representation of how country is known in this community, and how the central song cycle texts intersect with Yanyuwa tradition. What follows is a condensed and edited interview with Frances Devlin-Glass, in which John Bradley discusses the motivations, the hybridised methodologies employed, the innovations of this new genre, and the pedagogical ends served by this latest iteration of Yanyuwa song cycles.

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Film technology, in the broadest sense, embraces a vast array of knowledge, skills, tools, and systems. These include the codes and conventions of screen representation at the centre of much screen scholarship. The electro-mechanical tools of filmmaking are less often the focus of academic study than these codes and conventions, but they are central to them and to the daily work of artists and educators in the field of screen production. This paper traces the scope and significance of technical change, for independent film making, over the past four decades. Melbourne documentary filmmaker John Hughes provides a varied and expansive oeuvre through which to arrange an historical equipment list.

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Aim: This study investigated the effects of endurance training status and sex differences on skeletal muscle Na+,K+-pump mRNA expression, content and activity. Methods: Forty-five endurance-trained males (ETM), 11 recreationally active males (RAM), and nine recreationally active females (RAF) underwent a vastus lateralis muscle biopsy. Muscle was analysed for Na+,K+-pump α1, α2, α3, β1, β2 and β3 isoform mRNA expression (real-time reverse transcription-polymerase chain reaction), content ([3H]-ouabain-binding site) and maximal activity (3-O-methylfluorescein phosphatase, 3-O-MFPase). Results: ETM demonstrated lower α1, α3, β2 and β3 mRNA expression by 74%, 62%, 70% and 82%, respectively, than RAM (P < 0.04). In contrast, [3H]-ouabain binding and 3-O-MFPase activity were each higher in ETM than in RAM, by 16% (P < 0.03). RAM demonstrated a 230% and 364% higher α3 and b3 mRNA expression than RAF, respectively (P < 0.05), but no significant sex differences were found for α1, α2, β1 or β2 mRNA, [3H]-ouabain binding  or 3-O-MFPase activity. No significant correlation was found between years of endurance training and either [3H]-ouabain binding or 3-O-MFPase activity. Significant but weak correlations were found between the number of training hours per week and 3-O-MFPase activity (r = 0.31, P < 0.02) and between incremental exercise V O2(peak) and both   [3H]-ouabain binding (r = 0.33, P < 0.01) and 3-O-MFPase activity (r = 0.28, P < 0.03). Conclusions: Isoform-specific differences in Na+,K+-pump mRNA expression were found with both training status and sex differences, but only training status influenced Na+,K+-pump content and maximal activity in human skeletal muscle.

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Purpose: Five days of a high-fat diet produce metabolic adaptations that increase the rate of fat oxidation during prolonged exercise. We investigated whether enhanced rates of fat oxidation during submaximal exercise after 5 d of a high-fat diet would persist in the face of increased carbohydrate (CHO) availability before and during exercise.


Methods: Eight well-trained subjects consumed either a high-CHO (9.3 g·kg-1·d-1 CHO, 1.1 g·kg-1·d-1 fat; HCHO) or an isoenergetic high-fat diet (2.5 g·kg-1·d-1 CHO, 4.3 g·kg-1·d-1 fat; FAT-adapt) for 5 d followed by a high-CHO diet and rest on day 6. On day 7, performance testing (2 h steady-state (SS) cycling at 70% peak O2 uptake [[latin capital V with dot above]O2peak] + time trial [TT]) of 7 kJ·kg-1) was undertaken after a CHO breakfast (CHO 2 g·kg-1) and intake of CHO during cycling (0.8 g·kg-1·h-1).


Results: FAT-adapt reduced respiratory exchange ratio (RER) values before and during cycling at 70% [latin capital V with dot above]O2peak; RER was restored by 1 d CHO and CHO intake during cycling (0.90 ± 0.01, 0.80 ± 0.01, 0.91 ± 0.01, for days 1, 6, and 7, respectively). RER values were higher with HCHO (0.90 ± 0.01, 0.88 ± 0.01 (HCHO > FAT-adapt, P < 0.05), 0.95 ± 0.01 (HCHO > FAT-adapt, P < 0.05)). On day 7, fat oxidation remained elevated (73 ± 4 g vs 45 ± 3 g, P < 0.05), whereas CHO oxidation was reduced (354 ± 11 g vs 419 ± 13 g, P < 0.05) throughout SS in FAT-adapt versus HCHO. TT performance was similar for both trials (25.53 ± 0.67 min vs 25.45 ± 0.96 min, NS).


Conclusion: Adaptations to a short-term high-fat diet persisted in the face of high CHO availability before and during exercise, but failed to confer a performance advantage during a TT lasting ~ 25 min undertaken after 2 h of submaximal cycling.