41 research outputs found

    Experimental Passage of St. Louis Encephalitis Virus In Vivo in Mosquitoes and Chickens Reveals Evolutionarily Significant Virus Characteristics

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    St. Louis encephalitis virus (SLEV; Flaviviridae, flavivirus) was the major cause of epidemic flaviviral encephalitis in the U.S. prior to the introduction of West Nile virus (WNV) in 1999. However, outbreaks of SLEV have been significantly more limited then WNV in terms of levels of activity and geographic dispersal. One possible explanation for these variable levels of activity is that differences in the potential for each virus to adapt to its host cycle exist. The need for arboviruses to replicate in disparate hosts is thought to result in constraints on both evolution and host-specific adaptation. If cycling is the cause of genetic stability observed in nature and arboviruses lack host specialization, then sequential passage should result in both the accumulation of mutations and specialized viruses better suited for replication in that host. Previous studies suggest that WNV and SLEV differ in capacity for both genetic change and host specialization, and in the costs each accrues from specializing. In an attempt to clarify how selective pressures contribute to epidemiological patterns of WNV and SLEV, we evaluated mutant spectra size, consensus genetic change, and phenotypic changes for SLEV in vivo following 20 sequential passages via inoculation in either Culex pipiens mosquitoes or chickens. Results demonstrate that the capacity for genetic change is large for SLEV and that the size of the mutant spectrum is host-dependent using our passage methodology. Despite this, a general lack of consensus change resulted from passage in either host, a result that contrasts with the idea that constraints on evolution in nature result from host cycling alone. Results also suggest that a high level of adaptation to both hosts already exists, despite host cycling. A strain significantly more infectious in chickens did emerge from one lineage of chicken passage, yet other lineages and all mosquito passage strains did not display measurable host-specific fitness gains. In addition, increased infectivity in chickens did not decrease infectivity in mosquitoes, which further contrasts the concept of fitness trade-offs for arboviruses

    Editorial

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    Editorial of the Special Issue Early Childhood Music Education: European Perspectives. The papers collected together in this special issue were originally presented at the conference of the European Network of Early Childhood music educators and researchers (Eunet MERYC) held at the University of Bologna, Italy in the summer of 2009

    Case Study

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    Food Photography Dari Foto Biasa Jadi Luar Biasa

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    Dalam buku Food Photography: Dari Foto Biasa Jadi Luar Biasa ini, fotografer Nicole S. Young menyajikan dasar-dasar bagaimana menggunakan kamera dan peralatan lainnya?lights, lensa, refl ektor, dan lain sebagainya?serta menjelaskan kepada Anda prinsip-prinsip kunci fotografi seperti aperture, ISO, dan shutter speed. Nicole juga mendiskusikan tentang lighting (pencahayaan) dan komposisi, serta menunjukkan kepada Anda bagaimana mengarahkan gaya makanan (food style) dengan cara mengganjal, menggunakan kain, dan tablestops. Terakhir, ia juga menjelaskan kepada Anda bagaimana memperbaiki foto-foto Anda melalui sharpening, color enhancement, dan teknik-teknik editing lainnya. Dilengkapi dengan foto-foto besar berwarna dan menarik, buku ini menawarkan nasihatnasihat praktis dan saran-saran ahli bagaimana memotret foto-foto makanan yang Anda inginkan setiap kali Anda mengangkat kamera. Ikuti panduan dan saran ahli dari fotografer dan penulis Nicole S. Young di buku ini, dan Anda akan: ? Menggunakan setting-an kamera Anda untuk mendapatkan pengendalian penuh untuk melihat dan merasakan foto-foto Anda. ? Menjadi master pada dasar-dasar fotografi seperti komposisi, focus, depth of fi eld, dan banyak lagi lainnya. ? Belajar bagaimana meningkatkan foto-foto makanan Anda menggunakan teknikteknik food stylist professional. ? Mendapatkan tip-tip menggunakan tipe pencahayaan termasuk menggunakan strobes, fl ash, dan natural light. ? Meningkatkan kemampuan Anda menggunakan Adobe Photoshop ketika menangani foto-foto Anda. ? Lihat ke ?di belakang layar? dan Anda bisa mengikuti proses menciptakan foto-foto makanan dengan seluruh langkah sejak dari start hingga fi nish

    The Digital Geography Lab at Salem State University

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    Collective voices online. Discursive activism in #MeToo

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    The chapter investigates how women use the practice of speaking out in their activism to bring issues that are significant to them from the private sphere into the public sphere. Specifically, it focuses on analyzing how this was achieved in the case of the #MeToo movement, taken as the most prominent example of activism against sexual harassment in recent years. Using the conceptual tool of counter public sphere developed by Nancy Fraser, the chapter examines two relevant events from #MeToo: the sexual misconduct allegations against actor Aziz Ansari and the circulation of the so-called “Shitty Media Men” list
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