Particle response of antenna-coupled TES arrays: results from SPIDER and the laboratory

Future mm-wave and sub-mm space missions will employ large arrays of multiplexed transition-edge-sensor (TES) bolometers. Such instruments must contend with the high flux of cosmic rays beyond our atmosphere that induce ‘glitches’ in bolometer data, which posed a challenge to data analysis from the Planck bolometers. Future instruments will face the additional challenges of shared substrate wafers and multiplexed readout wiring. In this work, we explore the susceptibility of modern TES arrays to the cosmic ray environment of space using two data sets: the 2015 long-duration balloon flight of the SPIDER cosmic microwave background polarimeter, and a laboratory exposure of SPIDER flight hardware to radioactive sources. We find manageable glitch rates and short glitch durations, leading to minimal effect on SPIDER analysis. We constrain energy propagation within the substrate through a study of multi-detector coincidences and give a preliminary look at pulse shapes in laboratory data

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

Effect of removing Pityopsis Nervosa on the Soil Bacterial Microbiome of a Longleaf Pine Ecosystem

The longleaf pine (Pinus palustris) is an integral part of a diverse, endangered ecosystem in the Southeastern United States. Longleaf pines are better equipped to survive strong winds and droughts than other native species and are notable for their dependence on fire for successful regeneration and establishment. The herbaceous vegetation within this ecosystem provides suitable conditions for the longleaf pine by supporting a positive feedback loop with fire. The herbaceous community’s importance is well known, but the microbial community associated with these key players is currently understudied. The aim of this study is to investigate the association between soil microorganisms and two important herbaceous species in the longleaf pine ecosystem, Pityopsis nervosa and Andropogon sp. Pityopsis nervosa is the most dominant herbaceous species in the montane longleaf pine restoration sites studied; this forb plays a major role in ecosystem maintenance by serving as fuel for low-intensity fires. Two longleaf pine restoration sites in North Georgia were chosen. Six blocks were randomly set up at each site, and each block contained four randomized subplots with one of the following treatments: control, removal of Andropogon sp., removal of Pityopsis nervosa, and soil disturbance. DNA was extracted using a commercial extraction kit, measured for concentration, and analyzed to identify bacteria inhabiting the soil samples from each sublot. Preliminary results of these analyses indicated that Acidobacteria and Actinobacteria were among the most abundant phyla of bacteria present in each treatment group. Acidobacteria is a keystone taxon known to regulate biochemical cycles and promote plant growth. Actinobacteria are widely distributed in soil and secrete enzymes involved in degrading chitin and chitosan, play roles in carbon cycling, and degrade plant residues. Additional findings will add to the knowledge of these key microbial groups inhabiting the ecosystem and interacting with dominant herbaceous species such as Pityopsis nervosa

Investigating the Impact of the Removal of Andropogon Virginicus on the Soil Bacterial Microbiome of the Longleaf Pine

The longleaf pine (Pinus palustris), native to the Southeastern United States, is part of an endangered, pyrophytic ecosystem. The longleaf pine plays a significant role in the environment and is an important economic resource. It is currently considered the third most endangered ecosystem in the United States. Little is known about the microbial community within this ecosystem. The aim of this study is to investigate the effect of the removal of two dominant herbaceous species (Pityopsis nervosa and Andropogon sp.) on the bacterial soil microbiome of an area under restoration for the longleaf pine in the Piedmont region of Georgia. We focused on the effect of removing Andropogon sp., the second-most dominant grass species in the longleaf pine ecosystem. This species is notable for its ability to contribute to forest fires, which are necessary to the regeneration of the longleaf pine. Two longleaf pine restoration sites were chosen for this study. At each, six blocks were randomly set up containing four randomized subplots with one of the following treatments: control, removal of Andropogon sp., removal of Pityopsis nervosa, and soil disturbance. Soil samples were taken from each subplot in each block and DNA was extracted from soil using a commercially available kit. Further genetic analysis was performed to identify the bacteria that inhabit the soil microbiome in each treatment. Preliminary results include the presence of Proteobacteria and Planctomycetes. Planctomycetes are a phylum of terrestrial bacteria that inhabit soil microbial communities and are most notable for their ability to go through anammox in the nitrogen cycle. Proteobacteria are well known for their role in carbon, nitrogen, and sulfur cycling in soil. These results indicate key microbial groups and their functions to better understand the relationship between microbes and the herbaceous species the longleaf pine relies on

280 GHz Focal Plane Unit Design and Characterization for the SPIDER-2 Suborbital Polarimeter

We describe the construction and characterization of the 280 GHz bolometric focal plane units (FPUs) to be deployed on the second flight of the balloon-borne SPIDER instrument. These FPUs are vital to SPIDER's primary science goal of detecting or placing an upper limit on the amplitude of the primordial gravitational wave signature in the cosmic microwave background (CMB) by constraining the B-mode contamination in the CMB from Galactic dust emission. Each 280 GHz focal plane contains a 16 x 16 grid of corrugated silicon feedhorns coupled to an array of aluminum-manganese transition-edge sensor (TES) bolometers fabricated on 150 mm diameter substrates. In total, the three 280 GHz FPUs contain 1,530 polarization sensitive bolometers (765 spatial pixels) optimized for the low loading environment in flight and read out by time-division SQUID multiplexing. In this paper we describe the mechanical, thermal, and magnetic shielding architecture of the focal planes and present cryogenic measurements which characterize yield and the uniformity of several bolometer parameters. The assembled FPUs have high yields, with one array as high as 95% including defects from wiring and readout. We demonstrate high uniformity in device parameters, finding the median saturation power for each TES array to be ~3 pW at 300 mK with a less than 6% variation across each array at one standard deviation. These focal planes will be deployed alongside the 95 and 150 GHz telescopes in the SPIDER-2 instrument, slated to fly from McMurdo Station in Antarctica in December 2018