669 research outputs found

    Prevalence of \u3cem\u3eMyxobolus cerebralis\u3c/em\u3e Infections Among Genetic Lineages of \u3cem\u3eTubifex tubifex\u3c/em\u3e at Three Locations in the Madison River, Montana

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    Host biodiversity can impact disease risk and influence the transmission of parasitic disease. Stream sediment–dwelling worms, Tubifex tubifex (Clitellata: Oligochaeta), are the definitive host of the parasite Myxobolus cerebralis (Myxozoa: Myxosporea), which causes whirling disease in salmonid fishes. Genetic diversity of T. tubifex is correlated with host susceptibility to M. cerebralis, and mitochondrial Lineage III is generally shown to be more likely to be infected and produce the triactinomyxon (TAM) spores than other lineages. We determined the mitochondrial lineage, relative abundance, and prevalence of infection of T. tubifex collected at 3 sites in the Madison River, Montana, where previous study had shown variation in whirling disease prevalence and severity in caged trout fry. We also compared visual identification of TAMs released from cultured worms with a molecular genetic assay (diagnostic polymerase chain reaction [PCR]) for parasite detection of both infected and uninfected worms. We estimated that mitochondrial Lineage III was most abundant at the site previously shown to have high fish disease and was also most likely to be infected. The 2 techniques for detecting parasite infection did not always agree, and the likelihood of PCR (+) and spore (−) was not significantly different from PCR (−) and spore (+). Differences in the relative infection prevalence for these 2 lineages may explain the wide range of infection in natural streams

    The Parasite that Causes Whirling Disease, \u3cem\u3eMyxobolus cerebralis\u3c/em\u3e, is Genetically Variable Within and Across Spatial Scales

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    Understanding the genetic structure of parasite populations on the natural landscape can reveal important aspects of disease ecology and epidemiology and can indicate parasite dispersal across the landscape. Myxobolus cerebralis (Myxozoa: Myxosporea), the causative agent of whirling disease in the definitive host Tubifex tubifex, is native to Eurasia and has spread to more than 25 states in the USA. The small amounts of data available to date suggest that M. cerebralis has little genetic variability. We examined the genetic variability of parasites infecting the definitive host T. tubifex in the Madison River, MT, and also from other parts of North America and Europe. We cloned and sequenced 18S ribosomal DNA and the internal transcribed spacer-1 (ITS-1) gene. Five oligochaetes were examined for 18S and five for ITS-1, only one individual was examined for both genes. We found two different 18S rRNA haplotypes of M. cerebralis from five worms and both intra- and interworm genetic variation for ITS-1, which showed 16 different haplotypes from among 20 clones. Comparison of our sequences with those from other studies revealed M. cerebralis from MT was similar to the parasite collected from Alaska, Oregon, California, and Virginia in the USA and from Munich, Germany, based on 18S, whereas parasite sequences from West Virginia were very different. Combined with the high haplotype diversity of ITS-1 and uniqueness of ITS-1 haplotypes, our results show that M. cerebralis is more variable than previously thought and raises the possibility of multiple introductions of the parasite into North America

    Bridging the affordable rental housing gap : establishing a viable funding model to attract institutional investment

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    University of Technology, Sydney. Faculty of Design, Architecture and Building.The OECD states Australia's housing is by far the most over-valued in the Western World. Over one million Australian households have housing costs which are unaffordable which reduces money available for other essentials such as food, health care and education. Without intervention the number of effected households is forecast to double by 2020. Government strategies increasingly focus on rental subsidy to assist low income households. This strategy has proved to be inadequate to meet the continuing growth in demand for affordable housing. A new form of supply-led assistance is necessary. Government funding is limited and so the focus is on the private sector, specifically institutional investors to offer a viable solution. An issue for institutional investment is the gap between the perceived risk-adjusted return from affordable rental housing and that of alternate low risk asset classes. This gap is known as the rental gap. To bridge this gap a viable funding model needs to provide: an efficient structure to minimise the rental gap and lower the associated investment risk; and comply with current government policies. This research compares and contrasts the five leading rental housing affordability models that are currently prominent in Australia. To assist in identifying a viable funding model semi structured interviews of 18 key stakeholders of the affordable housing sector were obtained, including Chief Investment Officers of institutional investors, and other senior representatives of local and state governments, developers and not for profit housing groups. QSR's Nvivo software was used to analyse the stakeholders' views using a qualitative grounded theory approach with the findings considered against existing housing affordability literature. The research showed that investment in the housing affordability sector was primarily dependent on the current political environment. The ‘best’ funding model was a secondary consideration. In the current economic and political climate, the "tax credit model" met the key requirements. As institutional investors focus on both the return and associated risk, both real and perceived, improved information on the sector would result in a reduced the perception of risk and raise the likelihood of an attractive risk adjusted return. Bridging the Affordable Rental Gap: Establishing a Viable Funding Model to Attract Institutional Investment

    Distributive and Retributive Justice in Canada

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    The publications of the Law Reform Commission raise many ethical issues. One question - how distributive justice affects the working of retributive justice - is raised in several of their studies but not yet explicitly faced. This paper\u27 approaches the question by way of a reflection on Paul Weiler\u27s lucid and balanced argument, presented in The Reform of Punishment . 2 1 fully agree with the polemic thrust of Weiler\u27s essay, namely, that the rehabilitative model of corrections, which views crime as a disease, is inadequate and leads to injustice. What I aim to do here is to analyse and subject to some empirical scrutiny Weiler\u27s argument to re-establish a philosophical basis for a retributive understanding of criminal justice

    Close to home: notes on the post-publication withdrawal of a Spanish research paper

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    The rapid withdrawal from publication of a research article by a Spanish immunogeneticist and eight colleagues from Spain and Palestine was called "unprecedented" by one publishing ethics expert and was widely discussed during the winter of 2001 and 2002. The present paper analyzes the text of the retracted article, focusing on features that are often examined in English for specific purposes classes in an effort to discover how such features could have guided revision. The aspects named for study were the location and number of problematic wording decisions that drew fire for reasons unrelated to science, anomalous rhetorical patterns and the use of hedging. The paper was also compared to three others by the same first author. Finally, a paragraph from the Introduction was edited, in order to check the adequacy of the analysis of wording, moves and hedging for guiding revision. The results suggested that wording, thematic development, and clearly marked introductory and concluding moves, rather than hedging, would be relevant features to target for revision. The analysis includes discussion of how articles come to be published with language and rhetorical shortcomings and how a local author's editor, equipped with knowledge of the target genre, can guide author revision

    PENINGKATAN HASIL BELAJAR FISIKA KELAS XI MIPA SMAS SANTO DARIUS LARANTUKA MATERI GELOMBANG DENGAN MENGGUNAKAN PENDEKATAN PEMBELAJARAN INQUIRY TAHUN AJARAN 2021/2022

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    Peningkatan hasil belajar fisik kelas XI setelah menggunakan pendekatan pembelajaran INQUIRY mengalami perubahan dari siklus I jumlah peserta didik yang aktif dalam pembelajaran ada 5 orang dengan prosentase keaktifan sebesar 25%, peserta didik yang kurang aktif ada 15 orang dengan prosentase sebesar 75%. Sedangkan hasil observasi guru siklus I menunjukkan jumlah nilai peserta didik siklus I adalah 15,39 rata-rata kelas 3,85. Prosentase ketuntasan secara klasikal 33,33% dan melanjutkan penelitian ke siklus II sehingga hasil observasi peserta didik menunjukkan bahwa semua peserta didik aktif dalam pembelajaran dengan prosentase 100%. Dan hasil observasi guru menunjukkan bahwa jumlah nilai yang diperoleh dalam observasi guru siklus II adalah 15,90, dengan rata-rata skor adalah 3,97. Dengan melihat hasil yang diperoleh guru maka guru dikatakan baik dalam melaksanakan pembelajaran siklus II

    PENERAPAN MODEL PEMBELAJARAN PROBLEM BASED LEARNING (PBL) UNTUK MENINGKATKAN MOTIVASI BELAJAR PESERTA DIDIK PADA MATA PELAJARAN FISIKA, MATERI DINAMIKA PARTIKEL DI KELAS X MIPA SMAS SANTO DARIUS LARANTUKA TAHUN AJARAN 2019/2020

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    Dengan menerapkan model pembelajaran Problem Based Learning  untuk meningkatkan motivasi belajar didik mengalami perubahan dari setiap siklus, siklus I mencapai 16.56%  dan pada siklus II menjadi 90%. Sehingga kesimpulannya dengan menggunakan model pembelajarn PBL siswa mengalami peningkatan motivasi belaja

    Retired and Working

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