Project overview and update on WEAVE: the next generation wide-field spectroscopy facility for the William Herschel Telescope

We present an overview of and status report on the WEAVE next-generation spectroscopy facility for the William Herschel Telescope (WHT). WEAVE principally targets optical ground-based follow up of upcoming ground-based (LOFAR) and space-based (Gaia) surveys. WEAVE is a multi-object and multi-IFU facility utilizing a new 2-degree prime focus field of view at the WHT, with a buffered pick-and-place positioner system hosting 1000 multi-object (MOS) fibres, 20 integral field units, or a single large IFU for each observation. The fibres are fed to a single spectrograph, with a pair of 8k(spectral) x 6k (spatial) pixel cameras, located within the WHT GHRIL enclosure on the telescope Nasmyth platform, supporting observations at R~5000 over the full 370-1000nm wavelength range in a single exposure, or a high resolution mode with limited coverage in each arm at R~20000. The project is now in the final design and early procurement phase, with commissioning at the telescope expected in 2017.Comment: 11 pages, 11 Figures, Summary of a presentation to Astronomical Telescopes and Instrumentation 201

Inflammatory monocytes expressing tissue factor drive SIV and HIV coagulopathy

Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. http://www.sciencemag.org/about/science-licenses-journal-article-reuseThis is an article distributed under the terms of the Science Journals Default LicenseIn HIV infection, persistent inflammation despite effective antiretroviral therapy is linked to increased risk of noninfectious chronic complications such as cardiovascular and thromboembolic disease. A better understanding of inflammatory and coagulation pathways in HIV infection is needed to optimize clinical care. Markers of monocyte activation and coagulation independently predict morbidity and mortality associated with non-AIDS events. We identified a specific subset of monocytes that express tissue factor (TF), persist after virological suppression, and trigger the coagulation cascade by activating factor X. This subset of monocytes expressing TF had a distinct gene signature with up-regulated innate immune markers and evidence of robust production of multiple proinflammatory cytokines, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-6, ex vivo and in vitro upon lipopolysaccharide stimulation. We validated our findings in a nonhuman primate model, showing that TF-expressing inflammatory monocytes were associated with simian immunodeficiency virus (SIV)-related coagulopathy in the progressive [pigtail macaques (PTMs)] but not in the nonpathogenic (African green monkeys) SIV infection model. Last, Ixolaris, an anticoagulant that inhibits the TF pathway, was tested and potently blocked functional TF activity in vitro in HIV and SIV infection without affecting monocyte responses to Toll-like receptor stimulation. Strikingly, in vivo treatment of SIV-infected PTMs with Ixolaris was associated with significant decreases in D-dimer and immune activation. These data suggest that TF-expressing monocytes are at the epicenter of inflammation and coagulation in chronic HIV and SIV infection and may represent a potential therapeutic target.This study was supported by the NIH Intramural Research Program, National Institute of Allergy and Infectious Diseases, and Bench-to-Bedside award R01HL117715-10S1 (to I.S. and I.P.). Part of this project has been also funded with federal funds from the National Cancer Institute, NIH, under contract no. HHSN261200800001E. The NHP study has also been funded in part with federal funds from the NIH (R01 HL123096 and RO1 HL117715 to I.P., R01 AI119346 to C.A., and R01AI104373 to R.M.R.).info:eu-repo/semantics/publishedVersio

Construction progress of WEAVE: the next generation wide-field spectroscopy facility for the William Herschel Telescope

We present an update on the overall construction progress of the WEAVE next-generation spectroscopy facility for the William Herschel Telescope (WHT), now that all the major fabrication contracts are in place. We also present a summary of the current planning behind the 5-year initial phase of survey operations, and some detailed end-to-end science simulations that have been effected to evaluate the final on-sky performance after data processing. WEAVE will provide optical ground-based follow up of ground-based (LOFAR) and space-based (Gaia) surveys. WEAVE is a multi-object and multi-IFU facility utilizing a new 2-degree prime focus field of view at the WHT, with a buffered pick-and-place positioner system hosting 1000 multi-object (MOS) fibres, 20 integral field units, or a single large IFU for each observation. The fibres are fed to a single (dual-beam) spectrograph, with total of 16k spectral pixels, located within the WHT GHRIL enclosure on the telescope Nasmyth platform, supporting observations at R 5000 over the full 370-1000nm wavelength range in a single exposure, or a high resolution mode with limited coverage in each arm at R 20000. The project has experienced some delays in procurement and now has first light expected for the middle of 2019

Principles of Heating, Ventilating, and Air Conditioning

Principles of Heating, Ventilating, and Air Conditioning, Ninth Edition, is based on content from all four volumes of the ASHRAE Handbook, pulling heavily from the 2021 ASHRAE Handbook—Fundamentals. It contains the most current ASHRAE procedures and definitive yet easy-to-understand treatment of building HVAC systems, from basic principles through design and operation. This book is suitable both as a textbook and as a reference book for undergraduate engineering courses in the field of heating, ventilating, and air-conditioning; for similar courses at technical and vocational schools; for continuing education and refresher short courses for engineers; and for adult education courses for professionals other than engineers, especially when combined with the ASHRAE Handbook. Several significant changes have been made for this revised edition, including changes to chapter content and organization with the goal of ensuring the content is approachable and practical. For many chapters, a single example building is used to enhance consistency and further students’ understanding, and the removal of residential discussions and examples has given the book a more pointed focus on commercial calculations and applications. Specific changes include the following, among many others: The first chapter has been revised to provide not just history but also updated information regarding current trends and the possible future of the HVAC industry. The Thermodynamics and Psychrometrics chapter content has been reorganized, and additional materials on psychrometrics, including additional psychrometric charts covering low temperatures and higher elevations, have been included. The System Loads chapter reflects reorganization to better walk the user through the calculation process used by professionals. The Energy Estimating Methods chapter has been streamlined to better reflect the current processes used by today\u27s energy modelers and connects energy estimation with load calculations presented in the textbook. The Duct and Pipe Sizing chapter includes expanded information, tables, and charts used for hydronic pipe sizing with updated example problems, allowing for more thorough topic coverage. The Hydronic Heating and Cooling System Design chapter includes updated general content based on the latest design trends and requirements as well as expanded information on typical hydronic heating/cooling equipment and system types. In addition, several entire chapters have been removed from the print book but will be available online. The online materials include information on the following topics: Additional Psychrometric Charts Air-Processing Equipment Cogeneration and Heat Recovery Systems Economic Analyses and Life-Cycle Costs Heat Exchanger Equipment Heating Equipment Panel Heating and Cooling Systems Radiant Times Series (RTS) Method Refrigeration Equipment Systems Design Problemshttps://scholarworks.boisestate.edu/fac_books/1546/thumbnail.jp

State Misallocation and Housing Prices: Theory and Evidence from China. American Economic Review, forthcoming

This paper examines the equilibrium price effects of the privatization of housing assets that were previously owned and allocated by the state. I develop a theoretical framework that shows that privatization can have ambiguous effects on prices in the private market, and that the degree of misallocation of the assets prior to privatization determines the subsequent price effects. I test the predictions of the model using a large-scale housing reform in China. The results suggest that the removal of price distortions allowed households to increase their consumption of housing and led to an increase in equilibrium housing prices

Manufacturing process for the WEAVE prime focus corrector optics for the 4.2m William Hershel Telescope

In this paper, we detail the manufacturing process for the lenses that will constitute the new two-degree field-of-view Prime Focus Corrector (PFC) for the 4.2m William Herschel Telescope (WHT) optimised for the upcoming WEAVE Multi-Object Spectroscopy (MOS) facility. The corrector, including an Atmospheric Dispersion Corrector (ADC), is made of six large lenses, the largest being 1.1-meter diameter. We describe how the prescriptions of the optical design were translated into manufacturing specifications for the blanks and lenses. We explain how the as-built glass blank parameters were fed back into the optical design and how the specifications for the lenses were subsequently modified. We review the critical issues for the challenging manufacturing process and discuss the trade-offs that were necessary to deliver the lenses while maintaining the optimal optical performance. A short description of the lens optical testing is also presented. Finally, the subsequent manufacturing steps, including assembly, integration, and alignment are outlined

VPHGs for WEAVE: design, manufacturing and characterization

International audienceWEAVE is the next-generation optical spectroscopy facility for the William Herschel Telescope (WHT). It shows two channels (blue and red) and two working modes, a low-resolution (R=3,000-7,500) and a high-resolution (R=13,000- 25,000). The dispersing elements of the spectrograph are Volume Phase Holographic Gratings (VPHGs), two for the lower resolution mode and three for the higher resolution mode. Such gratings have a large size (clear aperture > 190 mm) and they are characterized by some key features, i.e. diffraction efficiency, wavefront error and dispersion that affect the final performances of the spectrograph. The VPHGs have been produced by KOSI based on the WEAVE design. After that, the VPHGs have been characterized, showing interesting results in terms of diffraction efficiency that reached peak values of 90%. As for the wavefront distortion, which is one of the critical aspect in VPHG technology, a different behavior between medium and high resolution elements was found. A larger wavefront distortion have been measured in the high resolution elements, because of the higher aspect ratio. A polishing process on the assembled VPHGs has been performed in order to reduce the wavefront distortion. Here, the results are presented and the specific issues discussed

Testing process for the WEAVE prime focus corrector lenses for the William Herschel Telescope

A new prime focus corrector for the WEAVE project for the William Herschel Telescope is being produced. The corrector consists of six lens elements, the largest being 1.1 m in diameter. It also incorporates an Atmospheric Dispersion Corrector. Testing procedures for the WEAVE prime focus corrector lens elements are described here. Critical issues encountered in practice, including the influence of the lens size, wedge and weight on the testing procedure are discussed. Due to large lens dimensions, a dedicated test tower and lens support system has been developed to measure the optical surface form errors of the concave surfaces and the transmitted wavefront of each lens. For some of the lens elements, sub-aperture measurements have been performed using an off-axis Hindle sphere and the resultant OPD maps have been stitched together. The challenge of testing a wedged lens with a combination of a long radius convex surface and a short radius concave surface has been resolved by using another lens from the system as an auxiliary lens. The practice of testing convex surfaces via internal reflection/transmission through the lens element has been avoided entirely in this case and some discussion justifying the choices of metrology approach taken is given. The fabrication and acceptance testing of the lens elements has been completed within the expected time and budget, and all elements have been shown to meet requirements