115 research outputs found

    Bringing Space to the Classroom Through STEM Education Providing Extreme Low Earth Orbit Missions Using ThinSats

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    The future of Space Science depends on our ability to attract and engage students into Science, Technology, Engineering and Mathematics (STEM) fields. Authentic, hands-on experience with space applications enhances engagement and learning in the STEM disciplines and can help to attract disinterested students to STEM careers. The Virginia Commercial Space Flight Authority (Virginia Space), Twiggs Space Lab, LLC (TSL), Orbital ATK, NearSpace Launch, Inc. (NSL), and NASA Wallops Flight Facility, have collaboratively developed the ThinSat Program, providing student teams the opportunity to design, develop, test, and monitor their own experimental payload which will be integrated into a pico-satellite and launched from the second stage of Orbital ATK’s Antares Rocket. The goal of the program is to provide students the opportunity to lead and participate in the development of a spacecraft payload through its life cycle over the course of an academic year. The student experience will be enhanced with classroom visits and videos created by the team to educate the students on satellite manufacturing, environmental testing, satellite integration, spaceport, launch vehicle, range and spacecraft operations. The ThinSat Program will provide a unique and important STEM opportunity for students to develop critical skills in systems engineering and space science that will complement existing programs

    A GIS-Based Prioritisation of Coastal Legacy Mine Spoil Deposits in England and Wales for Effective Future Management

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    Increases in coastal flooding and erosion due to climate change threaten many coastal mine waste deposits in the UK. As such, a robust approach to prioritising sites for management is required. A spatial dataset of 9094 mine spoil deposits in England and Wales was analysed against coastal erosion and flood projections to identify deposits most at-risk. Of these, 58 were at risk of tidal flooding and 33 of coastal erosion over the coming century. Within the 10 highest-priority deposits, 426,283 m3 of spoil was at risk of release by erosion, with Blackhall Colliery (County Durham) being the largest predicted contributor

    Genetic disorders of vitamin B12 metabolism: eight complementation groups – eight genes

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    Vitamin B12 (cobalamin, Cbl) is an essential nutrient in human metabolism. Genetic diseases of vitamin B12 utilisation constitute an important fraction of inherited newborn disease. Functionally, B12 is the cofactor for methionine synthase and methylmalonyl CoA mutase. To function as a cofactor, B12 must be metabolised through a complex pathway that modifies its structure and takes it through subcellular compartments of the cell. Through the study of inherited disorders of vitamin B12 utilisation, the genes for eight complementation groups have been identified, leading to the determination of the general structure of vitamin B12 processing and providing methods for carrier testing, prenatal diagnosis and approaches to treatment

    On the Use of Carbon Cables from Plastic Solvent Combinations of Polystyrene and Toluene in Carbon Nanotube Synthesis

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    For every three people on the planet, there are approximately two Tonnes (Te) of plastic waste. We show that carbon recovery from polystyrene (PS) plastic is enhanced by the coaddition of solvents to grow carbon nanotubes (CNTs) by liquid injection chemical vapour deposition. Polystyrene was loaded up to 4 wt% in toluene and heated to 780 °C in the presence of a ferrocene catalyst and a hydrogen/argon carrier gas at a 1:19 ratio. High resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Raman spectroscopy were used to identify multiwalled carbon nanotubes (MWCNTs). The PS addition in the range from 0 to 4 wt% showed improved quality and CNT homogeneity; Raman “Graphitic/Defective” (G/D) values increased from 1.9 to 2.3; mean CNT diameters increased from 43.0 to 49.2 nm; and maximum CNT yield increased from 11.37% to 14.31%. Since both the CNT diameters and the percentage yield increased following the addition of polystyrene, we conclude that carbon from PS contributes to the carbon within the MWCNTs. The electrical contact resistance of acid-washed Bucky papers produced from each loading ranged from 2.2 to 4.4 Ohm, with no direct correlation to PS loading. Due to this narrow range, materials with different loadings were mixed to create the six wires of an Ethernet cable and tested using iPerf3; the cable achieved up- and down- link speeds of ~99.5 Mbps, i.e., comparable to Cu wire with the same dimensions (~99.5 Mbps). The lifecycle assessment (LCA) of CNT wire production was compared to copper wire production for a use case in a Boeing 747-400 over the lifespan of the aircraft. Due to their lightweight nature, the CNT wires decreased the CO2 footprint by 21 kTonnes (kTe) over the aircraft’s lifespan.We would like to thank Keysight Technologies for the use of a test model of the B2900A SMU. We would like to acknowledge the assistance provided by Swansea University College of Engineering AIM Facility. We would like to thank TRIMTABS Ltd. for purchasing equipment required for making ethernet cables. Thanks to Swansea Employability Academy (SEA) for the summer placements scheme. Thanks to the Swansea University Texas Strategic Partnership. R.E.P. acknowledges his work was associated with the IMPACT operation. We acknowledge pixabay for use of imagery in the graphical abstract (https://pixabay.com/vectors/airplane-boeing-747-transport-48 11157/ (accessed on 1 December 2021))

    Design and Construction of Absorption Cells for Precision Radial Velocities in the K Band using Methane Isotopologues

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    We present a method to optimize absorption cells for precise wavelength calibration in the near-infrared. We apply it to design and optimize methane isotopologue cells for precision radial velocity measurements in the K band. We also describe the construction and installation of two such cells for the CSHELL spectrograph at NASA's IRTF. We have obtained their high-resolution laboratory spectra, which we can then use in precision radial velocity measurements and which can also have other applications. In terms of obtainable RV precision methane should out-perform other proposed cells, such as the ammonia cell (14^{14}NH3_{3}) recently demonstrated on CRIRES/VLT. The laboratory spectra of Ammonia and the Methane cells show strong absorption features in the H band that could also be exploited for precision Doppler measurements. We present spectra and preliminary radial velocity measurements obtained during our first-light run. These initial results show that a precision down to 20-30 m s1^{-1} can be obtained using a wavelength interval of only 5 nm in the K band and S/N\sim150. This supports the prediction that a precision down to a few m s1^{-1} can be achieved on late M dwarfs using the new generation of NIR spectrographs, thus enabling the detection of terrestrial planets in their habitable zones. Doppler measurements in the NIR can also be used to mitigate the radial velocity jitter due to stellar activity enabling more efficient surveys on young active stars.Comment: accepted PASP, Apr 2012 (in press). Preprint version with 36 pages, 9 Figures, 2 Table

    Colouration and Colour Changes of the Fiddler Crab, Uca capricornis: A Descriptive Study

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    Colour changes in animals may be triggered by a variety of social and environmental factors and may occur over a matter of seconds or months. Crustaceans, like fiddler crabs (genus Uca), are particularly adept at changing their colour and have been the focus of numerous studies. However, few of these studies have attempted to quantitatively describe the individual variation in colour and pattern or their adaptive significance. This paper quantitatively describes the colour patterns of the fiddler crab Uca capricornis and their ability to change on a socially significant timescale. The most dramatic changes in colour pattern are associated with moulting. These ontogenetic changes result in a general reduction of the colour pattern with increasing size, although females are more colourful and variable than similarly-sized males. Uca capricornis are also capable of rapid colour changes in response to stress, but show no endogenous rhythms associated with the semilunar and tidal cycles commonly reported in other fiddler crabs. The extreme colour polymorphism and the relative stability of the colour patterns in Uca capricornis are consistent with their use in visually mediated mate recognition

    Incorporating conceptual site models into national-scale environmental risk assessments for legacy waste in the coastal zone

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    Solid wastes deposited in the coastal zone that date from an era of lax environmental regulations continue to pose significant challenges for regulators and coastal managers worldwide. The increasing risk of contaminant release from these legacy disposal sites, due to a range of factors including rising sea levels, associated saline intrusion, and greater hydrological extremes, have been highlighted by many researchers. Given this widespread challenge, and the often-limited remedial funds available, there is a pressing need for the development of new advanced site prioritization protocols to limit potential pollution risks to sensitive ecological or human receptors. This paper presents a multi-criteria decision analysis that integrates the principles of Conceptual Site Models (Source-Pathway-Receptor) at a national scale in England and Wales to identify legacy waste sites where occurrence of pollutant linkages are most likely. A suite of spatial data has been integrated in order to score potential risks associated with waste type (Source), likelihood of pollutant release relating to current and future flood and erosion climate projections, alongside current management infrastructure (Pathway), and proximity to sensitive ecological features or proxies of human use in coastal areas (Receptors). Of the 30,281 legacy waste deposits identified in England and Wales, 3,219 were located within the coastal zone, with coastal areas containing a density of legacy wastes (by area) 10.5 times higher than inland areas. Of these, 669 were identified as priority sites in locations without existing coastal defences or flood management infrastructure, with 2550 sites identified in protected areas where contaminant transfer risks could still be apparent. The majority (63%) of the priority sites have either undefined source terms, or are classified as mixed wastes. Mining and industrial wastes were also notable waste categories, and displayed strong regional distributions in the former mining areas of north-east and south-west of England, south Wales, and post-industrial estuaries. The large-scale screening process presented here could be used by environmental managers as a foundation to direct more high-resolution site assessment and remedial work at priority sites, and can be used as a tool by governments for directing funding to problematic sites

    Effectiveness of integrating a pragmatic pathway for prescribing liraglutide 3.0mg in weight management services (STRIVE study): a multicentre, open-label, parallel-group, randomized controlled trial

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    Summary. Background: An effective prescribing pathway for liraglutide 3 mg, an approved obesity pharmacotherapy, may improve treatment access. This trial compared a targeted prescribing pathway for liraglutide 3 mg with multiple stopping rules in specialist weight management services (SWMS) to standard SWMS care. Methods: This phase four, two-year, multicentre, open-label, parallel-group, real-world randomized clinical trial (ClinicalTrials.gov: NCT03036800) enrolled adults with BMI ≥35 kg/m2 plus prediabetes, type 2 diabetes, hypertension or sleep apnoea from five SWMS in Ireland and UK. Participants were randomly allocated (2:1, stratified by centre and BMI) to SWMS care plus a targeted prescribing pathway for once daily subcutaneous liraglutide 3 mg (intervention) with stopping rules at 16 (≥5% weight loss, WL), 32 (≥10% WL) and 52 weeks (≥15% WL) or to SWMS care alone (control) through an online randomization service. The primary outcome was WL ≥15% at 52 weeks, assessed by complete cases analysis. All randomized participants were included in safety analysis. Findings From November 28, 2017 to February 28, 2020, 434 participants were screened, and 392 randomized (260 intervention; 132 control), while 294 (201 intervention; 93 control) included in the 52 weeks complete case analysis. More intervention than control participants achieved WL ≥15% at 52 weeks [51/201 (25.4%) vs 6/93 (6.5%); odds ratio 5.18; 95% CI 2.09, 12.88; p < 0.0001]. More adverse events occurred in the intervention (238/260, 91.5%; two deaths) than control (89/132, 67.4%; no deaths) group. Interpretation: A targeted prescribing pathway for liraglutide 3 mg helps more people achieve ≥15% WL at 52 weeks than standard care alone
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