928 research outputs found
RNA interference mediated in human primary cells via recombinant baculoviral vectors
No full textThe success of RNA interference (RNAi) in mammalian cells, mediated by siRNAs or shRNA-generating plasmids, is dependent, to an extent, upon transfection efficiency. This is a particular problem with primary cells, which are often difficult to transfect using cationic lipid vehicles. Effective RNAi in primary cells is thus best achieved with viral vectors, and retro-, adeno-, and lentivirus RNAi systems have been described. However, the use of such human viral vectors is inherently problematic, e.g., Class 2 status and requirement of secondary helper functions. Although insect cells are their natural host, baculoviruses also transduce a range of vertebrate cell lines and primary cells with high efficiency. The inability of baculoviral vectors to replicate in mammalian cells, their Class 1 status, and the simplicity of their construction make baculovirus an attractive alternative gene delivery vector. We have developed a baculoviral-based RNAi system designed to express shRNAs and GFP from U6 and CMV promoters, respectively. Transduction of Saos2, HepG2, Huh7, and primary human hepatic stellate cells with a baculoviral construct expressing shRNAs targeting lamin A/C resulted in effective knockdown of the corresponding mRNA and protein. Development of this baculoviral-based system provides an additional shRNA delivery option for RNAi-based investigations in mammalian cells
Population dynamics and habitat use of bottlenose dolphins (Tursiops aduncus), Bunbury, Western Australia
No full textCoastal dolphins are increasingly exposed to a variety of human activities through the proliferation of coastal development. Threats to dolphins in near-shore environments include the loss of suitable habitat, increasing vessel traffic and tourism, entanglement in fishing gear or other marine debris, noise pollution, environmental contaminants and disease. Baseline data and long-term monitoring are needed to inform effective management initiatives to conserve dolphin populations. This study focused on the bottlenose dolphin (Tursiops aduncus) population that inhabits the waters around the rapidly developing city of Bunbury, Western Australia. This study investigated the spatial and temporal variability in population abundance, social dynamics, calving seasonality, home range size and habitat use of dolphins in Bunbury waters over a three-year study period. From 2007-2010, year-round boat-based, photo-identification surveys followed pre-determined transect lines within a 120 km2 study area (212 transect lines total; N=578 dolphin group encounters) to achieve intensive and consistent sampling effort. Abundance and demographic parameters were estimated using the capture-recapture Robust Design model. The model with Markovian temporary emigration was favoured over other varying parameters (survival, capture probability and emigration time). Abundance estimates varied from 65 individuals (± SE 8.53; 95% CI: 54- 90) in winter 2007 to 139 individuals (±SE 3.41; 95% CI: 134-148) in autumn 2009. The apparent adult survival estimate was 0.985 (±SE 0.006; 95% CI: 0.964- 0.994). Calving peaked in late February to early March. Associations between adult females showed an annual seasonal cyclic pattern that peaked during the breeding and calving season. Home range estimates were important in identifying critical habitat areas. Home range areas for individual dolphins were estimated using the Minimum Convex Polygon method and adult females occupied statistically different sized areas (ANOVA: P ≤0.0001). Females in sheltered inner waters (Leschenault Estuary and Koombana Bay) had smaller home ranges (7.4-24.6km2; N=9) than those in exposed coastal areas (home ranges: 32.1-125.2km2; N=9). Seasonal differences in ranging patterns were analysed using the kernel density hotspot method. During the summer and autumn calving season, there was a hotspot for adult females on the lee-side of an artificial groyne, adjacent to the Estuary and Bay. Habitat use was explored further through maximum entropy modelling. Reef habitat had the strongest influence over dolphin presence whilst distance from coast was a weak predictor. Managers can now focus on protecting this critical habitat. This project has demonstrated the benefits of intensive multi-year research on a population by detecting the seasonal differences in abundance, behaviour and habitat use – information critical to managing human impacts on this species. Future research should combine our spatial understanding of this dolphin population and human use of the area to conduct a risk assessment and rank the threats to these dolphins
Book Review: Colin Milburn, Respawn: Gamers, Hackers, and Technogenic Life
No full textCopyright © 2020 (William Thomas Howe, [email protected]). Licensed under the Creative Commons
Attribution Non-commercial No Derivatives (by-nc-nd). Available at http://ijoc.org.Throughout the book Respawn: Gamers, Hackers, and
Technogenic Life, author Colin Milburn theorizes about the connections
between video games, hacking, science fiction, technological activism, and
technological communities
Orbit design for future SpaceChip swarm missions in a planetary atmosphere
No full textThe effect of solar radiation pressure and atmospheric drag on the orbital dynamics of satellites-on-a-chip (SpaceChips) is exploited to design equatorial long-lived orbits about the oblate Earth. The orbit energy gain due to asymmetric solar radiation pressure, considering the Earth's shadow, is used to balance the energy loss due to atmospheric drag. Future missions for a swarm of SpaceChips are proposed, where a number of small devices are released from a conventional spacecraft to perform spatially distributed measurements of the conditions in the ionosphere and exosphere. It is shown that the orbit lifetime can be extended and indeed selected through solar radiation pressure and the end-of-life re-entry of the swarm can be ensured, by exploiting atmospheric drag
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'A daughter come home?': the travel writings of Colleen J. McElroy
No full textOregon statewide status and trends report
No full textReport -- Appendix A. Black Rock Desert-Humboldt -- Appendix B. Columbia River -- Appendix C. Deschutes -- Appendix D. Goose Lake -- Appendix E. Grande Ronde -- Appendix F. John Day -- Appendix G. Klamath -- Appendix H. Malheur -- Appendix I. Mid Coast -- Appendix J. Middle-Columbia-Hood -- Appendix K. North Coast-Lower Columbia -- Appendix L. Oregon Closed Basins -- Appendix M. Owyhee -- Appendix N. Powder-Burnt -- Appendix O. Rogue -- Appendix P. Sandy -- Appendix Q. Snake River -- Appendix R. South Coast -- Appendix S. Umatilla-Walla Walla-Willow -- Appendix T. Umpqua -- Appendix U. Willamette.prepared by: Colin Donald and Ryan Michie.Title from PDF cover (viewed on November 4, 2022).This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Includes bibliographical references.Mode of access: Internet from the Oregon Government Publications Collection.Text in English
Oregon statewide status and trends report
No full textChapter 1-3. Introduction and Methods -- Chapter 4-5. Results and Citations -- Appendix A. Black Rock Desert-Humboldt -- Appendix B. Columbia River -- Appendix C. Deschutes -- Appendix D. Goose Lake -- Appendix E. Grande Ronde -- Appendix F. John Day -- Appendix G. Klamath -- Appendix H. Malheur -- Appendix I. Mid Coast -- Appendix J. Middle-Columbia-Hood -- Appendix K. North Coast-Lower Columbia -- Appendix L. Oregon Closed Basins -- Appendix M. Owyhee -- Appendix N. Powder-Burnt -- Appendix O. Rogue -- Appendix P. Sandy -- Appendix Q. Snake River -- Appendix R. South Coast -- Appendix S. Umatilla-Walla Walla-Willow -- Appendix T. Umpqua -- Appendix U. Willamette.prepared by: Colin Donald, Yuan Grund, and Ryan Michie.Title from PDF cover (viewed on October 27, 2020).This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Includes bibliographical references.Mode of access: Internet from the Oregon Government Publications Collection.Text in English
Oregon statewide status and trends report
No full textReport -- Appendix A. Black Rock Desert-Humboldt -- Appendix B. Columbia River -- Appendix C. Deschutes -- Appendix D. Goose Lake -- Appendix E. Grande Ronde -- Appendix F. John Day -- Appendix G. Klamath -- Appendix H. Malheur -- Appendix I. Mid Coast -- Appendix J. Middle-Columbia-Hood -- Appendix K. North Coast-Lower Columbia -- Appendix L. Oregon Closed Basins -- Appendix M. Black Owyhee -- Appendix N. Powder-Burnt -- Appendix O. Rogue -- Appendix P. Sandy -- Appendix Q. Snake River -- Appendix R. South Coast -- Appendix S. Umatilla-Walla Walla-Willow -- Appendix T. Umpqua -- Appendix U. Willamette.prepared by: Colin Donald, Ryan Michie, and Yuan Grund.Title from PDF cover (viewed on March 20, 2020).This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Includes bibliographical references.Mode of access: Internet from the Oregon Government Publications Collection.Text in English
The productivity effects of decentralized reforms - an analysis of the Chinese industrial reforms
No full textThe empirical literature on the effects of ownership has not distinguished between the effects of ownership and the effects of control. It has also generally ignored the dynamic effects of various ownership and control rights. Using a rich set of panel data about changes in China's state-owned enterprises, the author examines the static and dynamic effects of decentralizing ownership and control rights. He finds that productivity and growth rates improved significantly when reform improved the incentives for managers and employees to learn and to work hard - for example by decentralizing the rights to control wages, make production decisions, and appoint new managers. Increasing profit-retention rates and adopting performance contracts - conventionally viewed as the most important reforms for China's state enterprises - did not improve productivity much. Overall, decentralization accounted for a least 42 percent of productivity growth in Chinese state enterprises in the 1980s. Much of that gain came from improvements in the growth rate of productivity rather than in improved levels of productivity.Labor Policies,Economic Theory&Research,Environmental Economics&Policies,Banks&Banking Reform,Public Health Promotion,Economic Theory&Research,Environmental Economics&Policies,Banks&Banking Reform,Health Monitoring&Evaluation,Municipal Financial Management
Effect of poly rI:rC treatment upon the metabolism of [14C]-paracetamol in the BALB/cJ mouse
No full textThe effect of the immunomodulator, poly rI:rC, upon the in vivo metabolism of [14C]-paracetamol has been investigated in male BALB/cJ mice. In both poly rI:rC treated and control groups of mice the major part of the dose was excreted in the 0-24 hr urine and the major urinary metabolites were the glucuronic acid and sulphate conjugates. The urinary excretion of these two conjugates and of free paracetamol was not significantly altered following poly rI:rC treatment. Following enzymic hydrolysis of glucuronides and sulphates, the 3-cysteine, 3-mercapturate, 3-thiomethyl and 3-methylsulphoxide metabolites of paracetamol were all identified in the 0-24 hr urine together with very small amounts of 3-methoxy paracetamol. Although poly rI:rC treatment reduced the proportional urinary excretion of each of the thio adducts the individual differences were not significant. However, total thio adduct excretion, an indirect estimate of the metabolic activation of paracetamol, was significantly lower following poly rI:rC treatment. This depression in the urinary excretion of thio adducts following poly rI:rC treatment is discussed in relation to possible implications for paracetamol toxicity
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