On Internal Characterizations of CompletelyL-Regular Spaces

AbstractCompleteL-regularity is internally characterized in terms of separating chains of openL-sets. A possible characterization in terms of normal and separating families of closedL-sets is discussed and it is shown that spaces admitting such families are completelyL-regular. The question of whether the converse holds true remains open. Some partial solutions are however given, e.g. in the class of countably compact spaces

Optical Design of MAAT: an IFU for the GTC OSIRIS Spectrograph

Ground-based and airborne instrumentation for astronomy IX (2022), Montreal, jul 17-22, 2022.--Proceedings of SPIE - The International Society for Optical Engineering vol. 12184 Article number 1218465The Mirror-slicer Array for Astronomical Transients (MAAT) is a new IFU for the OSIRIS spectrograph on the 10.4-m Gran Telescopio CANARIAS (GTC) at La Palma, spectrograph that has been recently upgraded with a new detector and moved to the Cassegrain focus. Funding has been secured to build MAAT. We present the nearly final design, its expected performances, the different options that were studied, and an analysis of the spectrograph aberrations. MAAT will take advantage of the OSIRIS mask cartridge for multi-object spectroscopy. The IFU will be in a box that will take the place of a few masks. It is based on the Advanced Image Slicer (AIS) concept as are MUSE and KMOS on the VLT (among many others). The field is 10 '' x 7 '' with 23 slices 0.305 '' wide giving a spaxel size of 0.254 '' x 0.305 ''. The wavelength range is 360 nm to 1000 nm. The small space envelope, the maximum weight of the mask holder, and the curvature and tilt of the slit created additional design challenges. The spectral resolution will be about 1.6 times larger than with a standard slit of 0.6 '' because of the smaller size of the slices. All the eleven VPHs and grisms will be available to provide a broad spectral coverage with low to intermediate resolution (R=600 to 4100). To maximize the resolution of a spectrograph designed for a slit twice the width of the slices, we are in the process of measuring the wavefront of the spectrograph aberrations by using 2 out-of-focus masks with pinholes along the slit. We will then correct some of these aberrations with MAAT.We thank IAA-CSIC (Granada, Spain), DARK (Copenhagen, Denmark), OKC (Stockholm, Sweden) and USAL (Salamanca, Spain) to provide the necessary funding for the Final Review Phase of MAAT that supports the work presented in this paper.Peer reviewe

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

On quasi-uniform space valued semi-continuous functions

summary:F. van Gool [Comment. Math. Univ. Carolin. {\bf 33} (1992), 505--523] has introduced the concept of lower semicontinuity for functions with values in a quasi-uniform space (R,\Cal U). This note provides a purely topological view at the basic ideas of van Gool. The lower semicontinuity of van Gool appears to be just the continuity with respect to the topology T(\Cal U) generated by the quasi-uniformity \Cal U, so that many of his preparatory results become consequences of standard topological facts. In particular, when the order induced by \Cal U makes $R$ into a continuous lattice, then T(\Cal U) agrees with the Scott topology $\sigma (R)$ on $R$ and, thus, the lower semicontinuity reduces to a well known concept

Uniform-type structures on lattice-valued spaces and frames

By introducing lattice-valued covers of a set, we present a general framework for uniform structures on very general L-valued spaces (for L an integral commutative quantale). By showing, via an intermediate L-valued structure of uniformity, how filters of covers may describe the uniform operators of Hutton, we prove that, when restricted to Girard quantales, this general framework captures a significant class of Hutton's uniform spaces. The categories ofL-valued uniform spaces and L-valued uniform frames here introduced provide (in the case L is a complete chain) the missing vertices in the commutative cube formed by the classical categories of topological and uniform spaces and their corresponding pointfree counterparts (forming the base of the cube) and the corresponding L-valued categories (forming the top of the cube).http://www.sciencedirect.com/science/article/B6V05-4S21TH4-1/1/977fe355f240b1998e74eabadc8b61d