Design, Simulations and Development of a Miniature Detector System for Radiation Monitoring on Satellites

Space environment is particularly harsh for human activity and human assets. As human activity expands rapidly into space, it becomes ever more urgent to monitor the space environment in situ and in real time. This thesis aims to study a low re-source, miniature detector system to be employed on the satellites to monitor the in-situ space environment particularly for the hazard high energy particles. The vision is that every satellite even at small scale can afford to carry one such detector sys-tem. The core technology used in the detector system is scintillator + SiPM. The scintillator is a mature and traditional radiation detector and the SiPM is the latest generation of photon detector, which rapidly replaces the role of traditional PMT. Development of such detector system requires knowledge over space environment, detector material and geometry, electronics, data processing and more. This thesis tries to have a as complete coverage as possible to demonstrate the flow and the structure of such development. The thesis closely couples the theoretical knowledge to engineering realization. A detector system prototype for pioneering study is fully built and tested from end to end. This serves as the first stepping stone for the path to the full-scale space instrument

COTS Components Radiation Test Activity and Results at MSSL

This paper reports a full radiation test results for two popular commercial off the shelf (COTS) devices ADC128S102 and DAC121S101, targeted for use in MSSL's VIS instrument on ESA's EUCLID mission. The tests include total ionization dose (TID) and single event effect (SEE). The TID test shows both devices have passed 30krad test limit. Single event latch-up (SEL) has been observed at both devices at LET of 60 MeV.cm2.mg-1 or below

COTS Components Radiation Test Activity and Results at MSSL part 2

following the paper [1] presenting the full radiation test result of ADC128S102 and DAC121S101 in NSREC2016 conference, this paper continues to report the test results of another three popular commercial off the shelf (COTS) devices AD8065, DG612 and EL7457 under the same EUCLID mission program at MSSL. The tests cover both total ionization dose (TID) and single event effect (SEE). The paper aims to share the test results with the community and provides valuable data for any relevant research

LPS Regulates SOCS2 Transcription in a Type I Interferon Dependent Autocrine-Paracrine Loop

Recent studies suggest that SOCS2 is involved in the regulation of TLR signaling. In this study, we found that the expression of SOCS2 is regulated in human monocyte-derived DC by ligands stimulating TLR2, 3, 4, 5, 8 and 9 signaling. SOCS2 induction by LPS was dependent on the type I IFN regulated transcription factors IRF1 and IRF3 as shown by using silencing RNAs for IRFs. Blocking endogenous type I IFN signaling, by neutralizing antibodies to the receptor IFNAR2, abolished SOCS2 mRNA expression after TLR4 stimulation. Transcription factors STAT3, 5 and 6 displayed putative binding sites in the promoter regions of the human SOCS2 gene. Subsequent silencing experiments further supported that STAT3 and STAT5 are involved in LPS induced SOCS2 regulation. In mice we show that SOCS2 mRNA induction is 45% lower in bone marrow derived macrophages derived from MyD88−/− mice, and do not increase in BMMs from IRF3−/− mice after BCG infection. In conclusion, our results suggest that TLR4 signaling indirectly increases SOCS2 in late phase mainly via the production of endogenous type I IFN, and that subsequent IFN receptor signaling activates SOCS2 via STAT3 and STAT5

Formation flying test-bed development

Formation flying is currently a very popular idea in the space industry especially for the small satellite clusters. A robotic testbed to demonstrate and validate the formation flying theory is being done in many universities or institutes. In the Space Research Centre at Cranfield University, an aerobot testbed project aim at demonstrating the formation flying algorithm is launched in 2005. In 2005, the investigation of the testbed and an ultrasonic position system are done by Denis Di Filippantonio. This thesis is the second step of the project. A communication system using IEEE 802.15.4 protocol is developed and the network ability is evaluated. A demo control board centred with a dsPIC microcontroller is developed to evaluate the communication network and some other subsystems, such as motor control, battery health monitor. A future thinking of the project is concluded in the last chapter.Validerat; 20101217 (root

Residents’ Attention and Awareness of Urban Edible Landscapes: A Case Study of Wuhan, China

More and more urban residents in China have suffered from food insecurity and failed to meet the national recommendation of daily fruit and vegetable consumption due to rapid urbanization in recent years. Introducing edible landscapes to urban greening systems represents an opportunity for improving urban food supply and security. However, residents’ opinion on urban edible landscapes has rarely been discussed. In this study, questionnaire surveys were performed in eight sample communities in Wuhan, China, to collect the information on residents’ attention and awareness of urban edible landscapes. Results indicated that nearly one-third of the respondents were unaware of edible landscapes before the interview. Most residents thought that an edible landscape could promote efficient land use (57.26%) and express special ornamental effects (54.64%), but quite a few didn’t believe that growing edible plants in urban public spaces could increase food output (37.10%) and improve food quality (40.12%). Overall, 45.65% and 32.73% of the growers performed their cultivation behavior in private and semiprivate spaces, respectively. Lack of public areas for agriculture use was regarded as the main barrier restricting the development of urban horticulture by 55.86% of growers and 59.51% of non-growers. The residents were also worried about their property manager’s opposition, possible conflicts, and complex relationships with their neighbors. Food policies and infrastructure support from local governments and official institutions were needed to ensure the successful implementation of edible landscapes in urban areas

miR-365 Ameliorates Dexamethasone-Induced Suppression of Osteogenesis in MC3T3-E1 Cells by Targeting HDAC4

Glucocorticoid administration is the leading cause of secondary osteoporosis. In this study, we tested the hypotheses that histone deacetylase 4 (HDAC4) is associated with glucocorticoid-induced bone loss and that HDAC4 dependent bone loss can be ameliorated by miRNA-365. Our previous studies showed that miR-365 mediates mechanical stimulation of chondrocyte proliferation and differentiation by targeting HDAC4. However, it is not clear whether miR-365 has an effect on glucocorticoid-induced osteoporosis. We have shown that, in MC3T3-E1 osteoblasts, dexamethasone (DEX) treatment decreased the expression of miR-365, which is accompanied by the decrease of cell viability in a dose-dependent manner. Transfection of miR-365 ameliorated DEX-induced inhibition of MC3T3-E1 cell viability and alkaline phosphatase activity, and attenuated the suppressive effect of DEX on runt-related transcription factor 2 (Runx2), osteopontin (OPN), and collagen 1a1 (Col1a1) osteogenic gene expression. In addition, miR-365 decreased the expression of HDAC4 mRNA and protein by direct targeting the 3′-untranslated regions (3′-UTR) of HDAC4 mRNA in osteoblasts. MiR-365 increased Runx2 expression and such stimulatory effect could be reversed by HDAC4 over-expression in osteoblasts. Collectively, our findings indicate that miR-365 ameliorates DEX-induced suppression of cell viability and osteogenesis by regulating the expression of HDAC4 in osteoblasts, suggesting miR-365 might be a novel therapeutic agent for treatment of glucocorticoid-induced osteoporosis

Energy informatics: Fundamentals and standardization

Based on international standardization and power utility practices, this paper presents a preliminary and systematic study on the field of energy informatics and analyzes boundary expansion of information and energy system, and the convergence of energy system and ICT. A comprehensive introduction of the fundamentals and standardization of energy informatics is provided, and several key open issues are identified

Tertiary Amine-Catalyzed (4 + 2) Annulations of δ‑Acetoxy Allenoates: Synthesis of Multisubstituted 4<i>H</i>‑Pyran and 4<i>H</i>‑Chromene

The DABCO-catalyzed divergent (4 + 2) annulations of δ-acetoxy allenoates <b>1</b> are reported. The chemical behavior of <b>1</b> under DABCO catalyst was found to be substrate dependent. Allenoate <b>1</b> with an aromatic group at δC preferentially reacted with salicylaldehyde derivative <b>2</b>, delivering 4<i>H</i>-chromenes <b>3</b>. On the other hand, allenoates <b>1</b> with an alkyl group at δC readily underwent (4 + 2) annulations with oxo diene <b>4</b> to afford 4<i>H</i>-pyrans <b>5</b>