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Medieval Ceramics: Journal of the Medieval Ceramics Research Group, 40, 71-90, This paper seeks to investigate aspects of the form, manufacture, and possible provenance of drug jars from excavations carried out at Edinburgh Castle, and to set them in their wider context by studying comparable jars from other sites across Edinburgh's Old Town, both physically and scientifically, using Plasma spectrometry (ICP). They are also considered against wider patterns of distribution across Edinburgh and Leith, with reference to possible Scottish production sites and other notable archaeological assemblages in Scotland.

Medieval Ceramics: Journal of the Medieval Ceramics Research Group, 26-27, 101-104, This note describes recent research into the likely source of white-firing clays used in the medieval Surrey Whiteware industry. White-firing clay samples from Claypit Wood, Farnham Old Park are compared, using ICP-AES analysis, with samples from the medieval production centre at Eden Street, Kingston upon Thames. The clay sample is also tested for its potting qualities, plasticity and the range of temperatures at which it can be fired to produce both earthenware and stoneware vessels.

Medieval Ceramics: Journal of the Medieval Ceramics Research Group, 25, 135-137

Advances in solar array, electric propulsion (EP), and power beaming technologies will very likely enable future missions to the ice giants (Uranus and Neptune) by spacecraft that are completely solar powered. Between 1959 and 2001 the power from solar arrays on missions in Earth orbit have increased by five orders of magnitude (from 1 W to >100,000 W). Simultaneously, the use of solar power has been extended to ever larger distances from the Sun. Three solar powered missions out to solar ranges of just beyond 5 au have now been developed and flown (Rosetta, Juno, and Lucy). At these distances, the solar insolation is roughly 25 times lower than that at 1 au. Solar-powered spacecraft to Saturn, where the solar insolation is 100 times lower than that at 1 au have recently been proposed to NASA. A solar-powered mission to Uranus would have to function where solar insolation is only 4 times lower than it is at Saturn. For Neptune, it would be 9 times lower than at Saturn. Three improvements in solar array technology are required to make this feasible. First, solar cells have to be able to function in the low-intensity, low-temperature (LILT) environment at Uranus and Neptune. Specially designed triple-junction solar cells have been tested at JPL under LILT conditions equivalent to the environment at 30 au have shown excellent performance (high efficiency and high fill factor). Second, the size of deployable solar arrays has to increase by one to two orders of magnitude relative to the current state of the art. Third, the areal density of solar arrays has to be reduced by an order of magnitude. This will most likely be accomplished through a combination of new thin-film solar cell technology like the Perovskite cells under development worldwide and the development of new deployable solar array structures such as those under investigation for solar-powered satellites. The solar insolation at Uranus and Neptune is 400 to 900 times lower, respectively, than it is at 1 au. To provide sufficient power for a spacecraft at these destinations requires very large solar arrays. To be practical, such arrays will necessarily need to be very lightweight with a minimum structure mass. The gentle, low-thrust nature of electric propulsion is a good match for such solar arrays since the continuous acceleration of order 10⁻⁵ g will not drive increases in structure mass. In addition, the availability of large amounts of power provided by these arrays between 1 au and 5 to 10 au enables the design of low-thrust trajectories to the ice giants with attractive flight times. Existing ion propulsion technologies, such as NASA’s NEXT ion propulsion system enable flight times of conventionally sized spacecraft (≥1000 kg, not including the solar array) to Uranus of less than 10 years with reasonable propellant masses. For example, a conventionally sized spacecraft with a 150-kg complement of instruments could be delivered to Uranus orbit with a vehicle that has two 60-m x 60-m solar array wings and an areal density of 100 g/m² in a flight time of less than 10 years. The same-sized vehicle could be delivered to orbit around Neptune in a flight time of less than 18 years if the solar array areal density is reduced to 50 g/m². In both cases, larger payload masses can be delivered in similar flight times by increasing the size of the solar array wings. A 440-kg payload mass could be delivered to Neptune orbit in less than 17 years by increasing the solar array size to 70 m x 70 m. Smaller spacecraft may offer nearer-term opportunities. For example, coupling large, lightweight solar arrays with low-power ion propulsion systems (maximum input power of ~3 kW) can deliver net spacecraft masses to Uranus orbit of several hundred kilograms in flight times of less than 10 years. The only new development for such missions would be solar array wings with dimensions of 30 m x 30 m to 60 m x 60 m with an areal density of 100 g/m². The same EP system could deliver net spacecraft masses of 300 to 500 kg (inclusive of the payload, but not including the solar array, xenon tank, and xenon mass margin, which are tracked separately) to Neptune orbit with flight times of around 15 years with a 60-m x 60-m solar array that has an areal density of 50 g/m2. Such an array would provide roughly 2.4 kW at Neptune. The development of directed energy (DE) systems could potentially provide hundreds of watts of power continuously to landed assets from solar-powered orbiting spacecraft. Using a DE system to convert electrical power to light on the orbiting spacecraft and a photo-converter system on the landed asset to convert the DE light back to electricity is effectively a "photonic extension cord." For the DE side, a series of lasers in an array is used to beam power to distant landed assets over distances of hundreds to thousands of kilometers. The landed assets use high efficiency photovoltaics tuned to the laser frequency to convert the laser power back to electrical power. Thermal power from the photon power not converted to electricity may, in some applications, also be useful to the landed asset. State-of-the-art directed-energy systems are solid state, efficient (~50%), low mass (~1 kg/kW_(optical)), and long lifetime (~10⁵ hrs). This technology is improving rapidly, driven by the photonic revolution along with consumer and industrial demand. It is likely even possible to beam power to multiple stationary and even moving targets using unique optical beacons from each target. The technologies required for non-nuclear exploration of the solar system would also enable or enhance a wide variety of other missions of national interest. The large, ultra-light solar arrays combined with a state-of-the-art electric propulsion system would make possible the orbital exploration of Pluto, as well as a tour of its large moon Charon and smaller moons, with a reasonable mass margin and could potentially eliminate the need for RTGs for this mission. Large, ultra-light solar arrays and state-of-the-art electric propulsion systems could enable missions to chase down and encounter long-period comets and potentially even interstellar objects. This combination of technologies could enable solar electric propulsion (SEP) mission architectures farther out in the solar system, including: a Kuiper belt tour, centaur tour, or maybe even a ‘Grand Tour’ of the gas and ice giants without need for the most optimal planetary alignment, as with the Voyager missions. Sample returns are the next frontier in planetary exploration. The SEP and solar array technologies discussed here would facilitate sample return from a wide range of bodies, including possibly Ceres, Mars, Enceladus, Titan, Triton, and maybe even Mercury. Beaming power from a large, ultra-light solar array in orbit to a landed asset could enable non-nuclear surface exploration of the ice giant’s moons. In the nearer term, directed energy systems could deliver power to the surface of the Moon or Mars. Large, lighter solar arrays could facilitate lower-risk human missions to Mars using very high-power solar electric propulsion systems in mission architectures that don’t require rendezvousing with pre-deployed assets for the return trip. Finally, large, ultra-light solar arrays could power an Arecibo-like radar in space, to enhance characterization of potentially hazardous objects. Such high-power solar arrays combined with ion-beam deflection would be greatly enhance the nations’s planetary defense capabilities., Keck Institute for Space Studies 20220503-222804071

Background: Neoadjuvant systemic therapy (NST) is increasingly used in the treatment of breast cancer, yet it is clear that there is significant geographical variation in its use in the UK. This study aimed to examine stated practice across UK breast units, in terms of indications for use, radiological monitoring, pathological reporting of treatment response, and post-treatment surgical management. Methods: Multidisciplinary teams (MDTs) from all UK breast units were invited to participate in the NeST study. A detailed questionnaire assessing current stated practice was distributed to all participating units in December 2017 and data collated securely usingREDCap. Descriptive statistics were calculated for each questionnaire item. Results: Thirty-nine MDTs from a diverse range of hospitals responded. All MDTs routinely offered neoadjuvant chemotherapy (NACT) to a median of 10% (range 5–60%) of patients. Neoadjuvant endocrine therapy (NET) was offered to a median of 4% (range 0–25%) of patients by 66% of MDTs. The principal indication given for use of neoadjuvant therapy was for surgical downstaging. There was no consensus on methods of radiological monitoring of response, and a wide variety of pathological reporting systems were used to assess tumour response. Twenty-five percent of centres reported resecting the original tumour footprint, irrespective of clinical/radiological response. Radiologically negative axillae at diagnosis routinely had post-NACT or post-NET sentinel lymph node biopsy (SLNB) in 73.0 and 84% of centres respectively, whereas 16% performed SLNB pre-NACT. Positive axillae at diagnosis would receive axillary node clearance at 60% of centres, regardless of response to NACT. Discussion: There is wide variation in the stated use of neoadjuvant systemic therapy across the UK, with general low usage of NET. Surgical downstaging remains the most common indication of the use of NAC, although not all centres leverage the benefits of NAC for de-escalating surgery to the breast and/or axilla. There is a need for agreed multidisciplinary guidance for optimising selection and management of patients for NST. These findings will be corroborated in phase II of the NeST study which is a national collaborative prospective audit of NST utilisation and clinical outcomes.