1,253 research outputs found

    Effects of Private Insurance on Forest Landowners' Incentives to Sequester and Trade Carbon under Uncertainty: Impact of Hurricanes

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    We evaluate incentives of forest landowners for sequestering and trading carbon, given the risk of carbon loss from hurricanes, and an opportunity to insure their losses. Results of simulation model reveal that the effect of hurricane risk depends on the variability of returns from carbon and timber and landowners' ability to mitigate risk by diversifying forest holdings across regions or transferring risk by purchasing insurance.Carbon Sequestration, Emissions Trading, Natural Disaster, Risk, Insurance, Risk and Uncertainty, Q54, Q58,

    First Detection of Mid-Infrared Variability from an Ultraluminous X-Ray Source Holmberg II X-1

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    We present mid-infrared (IR) light curves of the Ultraluminous X-ray Source (ULX) Holmberg II X-1 from observations taken between 2014 January 13 and 2017 January 5 with the \textit{Spitzer Space Telescope} at 3.6 and 4.5 μ\mum in the \textit{Spitzer} Infrared Intensive Transients Survey (SPIRITS). The mid-IR light curves, which reveal the first detection of mid-IR variability from a ULX, is determined to arise primarily from dust emission rather than from a jet or an accretion disk outflow. We derived the evolution of the dust temperature (Td600800T_\mathrm{d}\sim600 - 800 K), IR luminosity (LIR3×104L_\mathrm{IR}\sim3\times10^4 L\mathrm{L}_\odot), mass (Md13×106M_\mathrm{d}\sim1-3\times10^{-6} M\mathrm{M}_\odot), and equilibrium temperature radius (Req1020R_\mathrm{eq}\sim10-20 AU). A comparison of X-1 with a sample spectroscopically identified massive stars in the Large Magellanic Cloud on a mid-IR color-magnitude diagram suggests that the mass donor in X-1 is a supergiant (sg) B[e]-star. The sgB[e]-interpretation is consistent with the derived dust properties and the presence of the [Fe II] (λ=1.644\lambda=1.644 μ\mum) emission line revealed from previous near-IR studies of X-1. We attribute the mid-IR variability of X-1 to increased heating of dust located in a circumbinary torus. It is unclear what physical processes are responsible for the increased dust heating; however, it does not appear to be associated with the X-ray flux from the ULX given the constant X-ray luminosities provided by serendipitous, near-contemporaneous X-ray observations around the first mid-IR variability event in 2014. Our results highlight the importance of mid-IR observations of luminous X-ray sources traditionally studied at X-ray and radio wavelengths.Comment: 9 page, 4 figures, 1 table, Accepted to ApJ Letter

    WFIRST: Enhancing Transient Science and Multi-Messenger Astronomy

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    Astrophysical transients have been observed for millennia and have shaped our most basic assumptions about the Universe. In the last century, systematic searches have grown from detecting handfuls of transients per year to over 7000 in 2018 alone. As these searches have matured, we have discovered both large samples of "normal" classes and new, rare classes. Recently, a transient was the first object observed in both gravitational waves and light. Ground-based observatories, including LSST, will discover thousands of transients in the optical, but these facilities will not provide the high-fidelity near-infrared (NIR) photometry and high-resolution imaging of a space-based observatory. WFIRST can fill this gap. With its survey designed to measure the expansion history of the Universe with Type Ia supernovae, WFIRST will also discover and monitor thousands of other transients in the NIR, revealing the physics for these high-energy events. Small-scale GO programs, either as a supplement to the planned survey or as specific target-of-opportunity observations, would significantly expand the scope of transient science that can be studied with WFIRST

    Bone marrow micrometastases in early breast cancer–30-year outcome

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    Background: Micrometastases in bone marrow of women with early breast cancer were first identified immunocytochemically in the 1980s. We report on the original cohort of women with a median follow-up of 30 years. Patients and Methods: In total, 350 women with primary breast cancer had eight bone marrow aspirates examined with antibody to epithelial membrane antigen. Data on long-term mortality were obtained via record linkage to death certification. Results: At a 30-year median follow-up, 79 out of 89 (89%) patients with micrometastases have died compared with 202 out of 261 (77%) without (hazard ratio = 1.46 (95% CI 1.12-1.90), P = 0.0043). Most marked effect of micrometastases on overall survival (OS) was seen in patients aged <= 50 at surgery (N = 97, P = 0.012), and on all patients within 10 years of diagnosis. In multivariable analyses, the presence of micrometastases was no longer a statistically significant prognostic factor. Conclusions: Bone marrow micrometastases are predictive for OS, particularly in the first decade and in younger patients

    Milkweed blended fabrics and their thermal insulation and UV protection properties

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    Two sets of milkweed blended weft knitted fabrics have been produced and then tested for their constructional properties like courses/wales per inch, thickness, weight and tightness factor. These fabrics are also evaluated for thermal insulation (TI), water vapour permeability, air permeability and ultraviolet protection factor (UPF) properties and then compared with the only cotton and polyester knitted fabrics. The UPF and TI data of various blends of milkweed fibre with cotton or polyester have beed evaluated using one-way analysis of variance (ANOVA). Results reveal that the thermal insulation and ultraviolet protection factor of the milkweed blended fabric are higher than the corresponding properties of cotton and polyester fabrics, while the air permeability and water permeability properties are lower than the corresponding properties of cotton and polyester knitted fabrics.

    Design and control of electronics based medical emergency system using a Quadcopter

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    Thesedays, there are many incidents that lead to road accidents, some being very severe. These accidents sometimes even result in loss of many lives. One of the major reasons for this loss is the lack of timely first aid. In fact, we observed from our survey conducted at an RTO that most deaths during accidents occur, due to delay or lack of first aid. The project focuses on developing a prototype of the system which would cater to the need of medical emergencies that arise during road accidents. This will be accomplished by use of a quadcopter which will deliver the required first aid. With this project, we are attempting to bring about faster accessibility to the patient, than other present means of medical emergency system. In order to achieve this goal, various means of communication will be utilized. The use of a camera will help to view the accident site. This will help to considerably bring down the death rates caused due to lack of timely first aid during accidents

    Low dose unfractionated heparin with low dose aspirin in treatment of thrombo prophylaxis in utero placental insufficiency: a new vision in heparinization during pregnancy

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    Background: The use of heparin and aspirin in obstetric care has grown considerably since their introduction into clinical practice. Because of the physiological changes of pregnancy, the usage of heparin and optimal dosage of heparin remains uncertain. Here our institute designed low dose Unfractionated Heparin (5000 IU s/c daily) as thrombo Prophylaxis regimen. To study the outcome of low dose UFH (5000 IU sc /daily) + Low dose aspirin (75 mg oral per day) for thrombo prophylaxis in utero placental insufficiency, in patient with 2 or more abortions.Methods: This retrospective study was conducted in 135 patients with 2 or more abortions as obstetric history. Prophylactic low dose of UFH (5000 IU s/c daily) + LDA 75 mg oral was initiated.  The Primary outcome is live birth, and secondary outcomes is Reduced incidence of early onset of gestational hypertension (HT), Intrauterine Growth Retardation (IUGR).Results: Out of 135 women 131 gave live birth, 2 had first trimester abortion and 2 had intrauterine death by 5 to 6 months. PIH was higher in patients with more than 30 years of age.Conclusions: In our Retrospective, data combination of low dose UFH (5000IU s/c) + LDA (75mg oral) is as safe as routine thrombo prophylaxis with good compliance

    Evaluation of anxiolytic activity of aqueous extract of Nerium oleander flowers in albino rats

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    Background: Anxiety has become a very important area of research interest in psychopharmacology as it affects one-eighth of the population worldwide. Benzodiazepines are still the most commonly used drugs for anxiety despite a number of side effects.There is a need for newer antianxiety drugs with increased safety and efficacy, hence this study was undertaken to evaluate the anxiolytic activity of Nerium oleander flowers.Methods: Aqueous extract of Nerium oleander flowers (NA) was prepared using soxhalet apparatus. A total of 24 Albino rats aged 8-10 weeks of either sex weighing about 100-150g were obtained and divided into 4 groups of 6 rats each. Group I: Normal saline 10mL/kg. Group II: Diazepam 2mg/kg Group III: NA at a dose of 200 mg/kg Group IV: NA at a dose of 400mg/kg. The anxiolytic activity of Aqueous extract of NA was tested by elevated plus maze and digital actophotometer models. Data was analysed using one way ANOVA followed by Posthoc Tukey’s test.Results: In EPM model, the NA at 200, 400mg/kg doses showed that the number of entries and time spent in the open arms were increased significantly as compared to the control animals. (p&lt;0.001). In Actophoptometer model, two different doses of NA (200 and 400mg/kg) showed a dose-dependent decrease in the locomotor activity, when compared to the control animals (p&lt;0.001).Conclusions: Both the doses of aqueous extract of Nerium oleander flowers (200mg and 400mg/kg) possess anxiolytic activity and could be used as a new approach to treat anxiety
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