933 research outputs found

    A Next Generation High-speed Data Acquisition System for Multi-channel Infrared and Optical Photometry

    Get PDF
    We report the design, operation, and performance of a next generation high-speed data acquisition system for multi-channel infrared and optical photometry based on the modern technologies of Field Programmable Gate Arrays, the Peripheral Component Interconnect bus, and the Global Positioning System. This system allows either direct recording of photon arrival times or binned photon counting with time resolution up to 1-μ\mus precision in Universal Time, as well as real-time data monitoring and analysis. The system also allows simultaneous recording of multi-channel observations with very flexible, reconfigurable observational modes. We present successful 20-μ\mus resolution simultaneous observations of the Crab Nebula Pulsar in the infrared (H-band) and optical (V-band) wavebands obtained with this system and 100-μ\mus resolution V-band observations of the dwarf nova IY Uma with the 5-m Hale telescope at the Palomar Observatory.Comment: 11 pages, including 4 figures, to appear in PAS

    Direct and Legacy Effects of Long-Term Elevated CO2 on Fine Root Growth and Plant-Insect Interactions

    Get PDF
    Increasing atmospheric CO2 concentrations alter leaf physiology, with effects that cascade to communities and ecosystems. Yet, responses over cycles of disturbance and recovery are not well known, because most experiments span limited ecological time. We examined the effects of CO2 on root growth, herbivory and arthropod biodiversity in a woodland from 1996 to 2006, and the legacy of CO2 enrichment on these processes during the year after the CO2 treatment ceased. We used minirhizotrons to study root growth, leaf censuses to study herbivory and pitfall traps to determine the effects of elevated CO2 on arthropod biodiversity. Elevated CO2 increased fine root biomass, but decreased foliar nitrogen and herbivory on all plant species. Insect biodiversity was unchanged in elevated CO2. Legacy effects of elevated CO2 disappeared quickly as fine root growth, foliar nitrogen and herbivory levels recovered in the next growing season following the cessation of elevated CO2. Although the effects of elevated CO2 cascade through plants to herbivores, they do not reach other trophic levels, and biodiversity remains unchanged. The legacy of 10yr of elevated CO2 on plant-herbivore interactions in this system appear to be minimal, indicating that the effects of elevated CO2 may not accumulate over cycles of disturbance and recovery

    Militarization and social development in the Third World

    Full text link
    In this study we integrated the modernization and dependency theories of development to suggest the ways whereby militarization can affect development. We examined the effects of three components of militarization highlighted in these theories on the social development of ninety-two developing countries. Overall, our findings support the dependency theory's emphasis on the detrimental impact of international trade on disadvantaged nations. There is a significant negative correlation between arms import and social development. Arms export and indigenous spending are correlated with social development in the expected directions but their beta coefficients are not significant. The diverse ways these three aspects of militarization have been shown to affect social development help to explain some of the conflicting findings in the literature and point to the need to study these variables in their disaggregated form.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69141/2/10.1177_144078339503100105.pd

    Establishing a core outcome set for peritoneal dialysis : report of the SONG-PD (standardized outcomes in nephrology-peritoneal dialysis) consensus workshop

    Get PDF
    Outcomes reported in randomized controlled trials in peritoneal dialysis (PD) are diverse, are measured inconsistently, and may not be important to patients, families, and clinicians. The Standardized Outcomes in Nephrology-Peritoneal Dialysis (SONG-PD) initiative aims to establish a core outcome set for trials in PD based on the shared priorities of all stakeholders. We convened an international SONG-PD stakeholder consensus workshop in May 2018 in Vancouver, Canada. Nineteen patients/caregivers and 51 health professionals attended. Participants discussed core outcome domains and implementation in trials in PD. Four themes relating to the formation of core outcome domains were identified: life participation as a main goal of PD, impact of fatigue, empowerment for preparation and planning, and separation of contributing factors from core factors. Considerations for implementation were identified: standardizing patient-reported outcomes, requiring a validated and feasible measure, simplicity of binary outcomes, responsiveness to interventions, and using positive terminology. All stakeholders supported inclusion of PD-related infection, cardiovascular disease, mortality, technique survival, and life participation as the core outcome domains for PD

    Integrative Genetic Manipulation of Plasmodium cynomolgi Reveals Multidrug Resistance-1 Y976F Associated With Increased In Vitro Susceptibility to Mefloquine

    Get PDF
    The lack of a long-term in vitro culture method has severely restricted the study of Plasmodium vivax, in part because it limits genetic manipulation and reverse genetics. We used the recently optimized Plasmodium cynomolgi Berok in vitro culture model to investigate the putative P. vivax drug resistance marker MDR1 Y976F. Introduction of this mutation using clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 (CRISPR-Cas9) increased sensitivity to mefloquine, but had no significant effect on sensitivity to chloroquine, amodiaquine, piperaquine, and artesunate. To our knowledge, this is the first reported use of CRISPR-Cas9 in P. cynomolgi, and the first reported integrative genetic manipulation of this species

    Regulators of genetic risk of breast cancer identified by integrative network analysis.

    Get PDF
    Genetic risk for breast cancer is conferred by a combination of multiple variants of small effect. To better understand how risk loci might combine, we examined whether risk-associated genes share regulatory mechanisms. We created a breast cancer gene regulatory network comprising transcription factors and groups of putative target genes (regulons) and asked whether specific regulons are enriched for genes associated with risk loci via expression quantitative trait loci (eQTLs). We identified 36 overlapping regulons that were enriched for risk loci and formed a distinct cluster within the network, suggesting shared biology. The risk transcription factors driving these regulons are frequently mutated in cancer and lie in two opposing subgroups, which relate to estrogen receptor (ER)(+) luminal A or luminal B and ER(-) basal-like cancers and to different luminal epithelial cell populations in the adult mammary gland. Our network approach provides a foundation for determining the regulatory circuits governing breast cancer, to identify targets for intervention, and is transferable to other disease settings.This work was funded by Cancer Research UK and the Breast Cancer Research Foundation. MAAC is funded by the National Research Council (CNPq) of Brazil. TEH held a fellowship from the US DOD Breast Cancer Research Program (W81XWH-11-1-0592) and is currently supported by an RAH Career Development Fellowship (Australia). TEH and WDT are funded by the NHMRC of Australia (NHMRC) (ID: 1008349 WDT; 1084416 WDT, TEH) and Cancer Australia/National Breast Cancer Foundation (ID 627229; WDT, TEH). BAJP is a Gibb Fellow of Cancer Research UK. We would like to acknowledge the support of The University of Cambridge, Cancer Research UK and Hutchison Whampoa Limited.This is the author accepted manuscript. The final version is available from NPG via http://dx.doi.org/10.1038/ng.345

    The Efficacy of Tetracyclines in Peripheral and Intracerebral Prion Infection

    Get PDF
    We have previously shown that tetracyclines interact with and reverse the protease resistance of pathological prion protein extracted from scrapie-infected animals and patients with all forms of Creutzfeldt-Jakob disease, lowering the prion titre and prolonging survival of cerebrally infected animals. To investigate the effectiveness of these drugs as anti-prion agents Syrian hamsters were inoculated intramuscularly or subcutaneously with 263K scrapie strain at a 10−4 dilution. Tetracyclines were injected intramuscularly or intraperitoneally at the dose of 10 mg/kg. A single intramuscular dose of doxycycline one hour after infection in the same site of inoculation prolonged median survival by 64%. Intraperitoneal doses of tetracyclines every two days for 40 or 44 days increased survival time by 25% (doxycycline), 32% (tetracycline); and 81% (minocycline) after intramuscular infection, and 35% (doxycycline) after subcutaneous infection. To extend the therapeutic potential of tetracyclines, we investigated the efficacy of direct infusion of tetracyclines in advanced infection. Since intracerebroventricular infusion of tetracycline solutions can cause overt acute toxicity in animals, we entrapped the drugs in liposomes. Animals were inoculated intracerebrally with a 10−4 dilution of the 263K scrapie strain. A single intracerebroventricular infusion of 25 µg/ 20 µl of doxycycline or minocycline entrapped in liposomes was administered 60 days after inoculation, when 50% of animals showed initial symptoms of the disease. Median survival increased of 8.1% with doxycycline and 10% with minocycline. These data suggest that tetracyclines might have therapeutic potential for humans
    corecore