An unusual case of intertrigo in an adult caused by purely cutaneous Langerhans cell histiocytosis

We report a case of persistent intertrigo in an adult, eventually diagnosed as cutaneous Langerhans cell histiocytosis (LCH). It is known that LCH has a predilection for intertriginous areas, however purely cutaneous disease as in our case, is uncommon and usually other systems are affected. Following the report, literature of similar cases is reviewed to determine possible outcomes and to decide on the best possible treatment options.peer-reviewe

Archaeological test pit excavations at Meldreth, Cambridgeshire

This report presents the results of a programme of archaeological excavation of 32 1m2 ‘test pits’ in the Cambridgeshire village of Meldreth carried out in summer 2013. The programme was funded by the Heritage Lottery Fund (HLF) through its ‘All Our Stories’ programme and supported by the Arts and Humanities Research Council (AHRC) Connected Communities theme which funded the Cambridge Community Heritage programme at the University of Cambridge in 20012-13. Over three weekends, more than 300 residents of the village of Meldreth and the local area took part in the excavations in 32 different locations throughout the present village. The results provided new evidence for the development of the area now occupied by the village, which mostly lies alongside a small stream, from the prehistoric period onwards. Parts of the area appears to have been quite intensively used by humans in the prehistoric period, with unusually large volumes of Bronze Age pottery recovered from at least four different sites likely to be indicative of settlement and/or burial. Pottery of Roman date favours the south of the present village, and suggests settlement took the form of a dispersed scatter of small settlements such as farmsteads surrounded by arable fields to the north. No evidence was found for any activity dating to the period between the 5th –9th centuries AD, but Saxo-Norman pottery was found widely, with particular concentrations on the manorial site of Topcliffe as well as in the south of the village around Flambards moated site. The absence of any Thetford ware from Meldreth suggests that this activity is likely to be post-Conquest in date and that the medieval settlement originates in this period rather than earlier. The high medieval period sees the settlement extend westwards, probably laid out in the 12th or 13th century over former arable, with apparently new settlement sites founded at Chiswick and North End. This growth ceases in the late medieval period, although Meldreth does not appear to be as badly affected in this period of widespread demographic and settlement contraction as many settlements in the eastern region. In the post-medieval period, however, the test pit data indicates that Meldreth stagnated, with the southern end of the settlement particularly badly affected

Optimising I-V measurements of high capacitance modules using dark impedance measurements

A method is demonstrated to optimise pulsed IV measurements of high capacitance PV modules, using dark IV and impedance measurements. The impact of capacitance during I-V measurements is minimised by changing the shape of the voltage ramp. The optimisation can be performed simply and automatically for each individual module during the charging period for the simulator. As an additional benefit of this method the extracted C-V profile can be used to estimate the minority carrier lifetime for the module. The system is demonstrated by using a high capacitance n type module, which is successfully measured in a single 10ms illumination pulse

Transient preconditioning in CIGS solar cells and modules

Transient preconditioning refers to a light induced performance change in CIGS which occurs and relaxes on a millisecond to seconds timescale. This effect appears to be distinct from the better known and more persistent preconditioning which typically takes several hours or days to relax. In this paper some properties of this phenomenon are explored including the variation of if the effect with voltage and temperature. The consequences for repeatable and accurate device measurement are explored. In particular the transient rise in photocurrent during measurements using a pulsed simulator can be successfully eradicated using voltage preconditioning when there is no gap between the preconditioning voltage being applied and the start of the illumination pulse

Parathyroid carcinoma : clinical course, diagnosis and management

Parathyroid carcinoma is a rare cause of primary hyperparathyroidism often resulting in severe hypercalcaemia. It tends to follow a rather aggressive course with a high propensity for locoregional spread and distant metastasis. En bloc resection is the mainstay of treatment, with surgery also playing a role in the palliation of hypercalcaemia for recurrent and metastatic disease. While adjuvant chemotherapy and radiotherapy have shown disappointing outcomes, bisphosphonates and calcimimetic agents are effective in the management of recalcitrant hypercalcaemia in parathyroid carcinoma. We report a case of parathyroid carcinoma in a lady who initially presented with a neck mass, severe hypercalcaemia, a bony swelling over the shin and elevated parathyroid hormone levels. The diagnosis was confirmed histologically following a thyroid lobectomy, isthmectomy and parathyroidectomy. In the three years which followed the patient received two courses of palliative radiotherapy, two thoracotomies for pulmonary metastatectomy, an extensive neck re-exploration and fashioning of a tracheostomy for aggressive local recurrence with invasion of the larynx.peer-reviewe

Validation of spectral response polychromatic method measurement of full size photovoltaic modules using outdoor measured data

This paper presents the validation of a polychromatic method of spectral response measurement applied to full size mono-crystalline silicon photovoltaic modules using outdoor measured data. The difference between short-circuit current modelled from the measured spectral response and outdoor spectral irradiance and the directly-measured current is below 5% which confirms the validity of the spectral response curve obtained using the polychromatic measurement method

Influences on the energy delivery of thin film photovoltaic modules

The energy yield delivered by different types of photovoltaic device is a key consideration in the selection of appropriate technologies for cheap photovoltaic electricity. The different technologies currently on the market, each have certain strengths and weaknesses when it comes to operating in different environments. There is a plethora of comparative tests on-going with sometimes contradictory results. This paper investigates device behaviour of contrasting thin film technologies, specifically a-Si and CIGS derivatives, and places this analysis into context with results reported by others. Specific consideration is given to the accuracy of module inter-comparisons, as most outdoor monitoring at this scale is conducted to compare devices against one another. It is shown that there are five main contributors to differences in energy delivery and the magnitude of these depends on the environments in which the devices are operated. The paper shows that two effects, typically not considered in inter-comparisons, dominate the reported energy delivery. Environmental influences such as light intensity, spectrum and operating temperature introduce performance variations typically in the range of 2–7% in the course of a year. However, most comparative tests are carried out only for short periods of time, in the order of months. Here, the power rating is a key factor and adds uncertainty for new technologies such as thin films often in the range of 10–15%. This dominates inter-comparisons looking at as-new, first-year energy yields, yet considering the life-time energy yield it is found that ageing causes up to 25% variation between different devices. The durability of devices and performance-maintenance is thus the most significant factor affecting energy delivery, a major determinant of electricity cost. The discussion is based on long-term measurements carried out in Loughborough, UK by the Centre for Renewable Energy Systems Technology (CREST) at Loughborough University

Influences on the energy delivery of thin film photovoltaic modules

The energy yield delivered by different types of photovoltaic device is a key consideration in the selection of appropriate technologies for cheap photovoltaic electricity. The different technologies currently on the market, each have certain strengths and weaknesses when it comes to operating in different environments. There is a plethora of comparative tests on-going with sometimes contradictory results. This paper investigates device behaviour of contrasting thin film technologies, specifically a-Si and CIGS derivatives, and places this analysis into context with results reported by others. Specific consideration is given to the accuracy of module inter-comparisons, as most outdoor monitoring at this scale is conducted to compare devices against one another. It is shown that there are five main contributors to differences in energy delivery and the magnitude of these depends on the environments in which the devices are operated. The paper shows that two effects, typically not considered in inter-comparisons, dominate the reported energy delivery. Environmental influences such as light intensity, spectrum and operating temperature introduce performance variations typically in the range of 2–7% in the course of a year. However, most comparative tests are carried out only for short periods of time, in the order of months. Here, the power rating is a key factor and adds uncertainty for new technologies such as thin films often in the range of 10–15%. This dominates inter-comparisons looking at as-new, first-year energy yields, yet considering the life-time energy yield it is found that ageing causes up to 25% variation between different devices. The durability of devices and performance-maintenance is thus the most significant factor affecting energy delivery, a major determinant of electricity cost. The discussion is based on long-term measurements carried out in Loughborough, UK by the Centre for Renewable Energy Systems Technology (CREST) at Loughborough University

Spectral changes of solar simulator xenon flash bulbs over lifetime and its effects on measurement uncertainty

The effects of lamp age on the spectral output of solar simulator xenon flash lamps and spectral output measurement uncertainty on the spectral mismatch are investigated. It is demonstrated that the spectrum of an older lamp set has a relatively lower blue and larger red content compared to a new set of bulbs. Measurements over the life-time of several sets of bulbs showed large unexpected variations due measurement uncertainty in spectral measurements themselves. The main influencing factors are investigated and a faulty temperature control is found to be the main source of uncertainty. It is shown that this alone can affect the mismatch calculation to a larger degree than the MMF would correct in itself

The LightSail 2 Controlled Solar Sailing Demonstration Mission

The LightSail 2 mission is the culmination of a decade-long program sponsored by The Planetary Society to advance solar sailing technology. The objective of LightSail 2 is to demonstrate controlled solar sailing in Earth orbit using a CubeSat platform. The LightSail 2 attitude is controlled using a single-axis momentum wheel and magnetic torque rods. During solar sailing operations, two 90 degree slews are performed each orbit to harness momentum from solar photons. Flight data show that LightSail 2 is successfully controlling its orientation relative to the Sun, and the controlled thrust from solar radiation pressure is measurably reducing the rate of orbital decay. The Planetary Society declared LightSail 2 mission success on July 31, 2019. This paper provides an overview of the LightSail 2 mission implementation, including the design of the flight system and flight software, and the pre-launch testing program. A summary of LightSail 2 mission operations is provided, including a description of the ground system. Solar sailing performance is presented, and anomalies encountered during the mission are discussed. The flight team continues to refine solar sailing performance and conduct on-orbit imaging for engineering purposes and to engage public interest. The LightSail program is entirely donor-funded, with over 50,000 contributors around the globe