51 research outputs found

    Countermeasure for negative impact of practical source in continuous-variable measurement-device-independent quantum key distribution

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    Continuous-variable measurement-device-independent quantum key distribution (CV-MDI QKD) can defend all attacks on the measurement devices fundamentally. Consequently, higher requirements are put forward for the source of CV-MDI QKD system. However, the imperfections of actual source brings practical security risks to the CV-MDI QKD system. Therefore, the characteristics of the realistic source must be controlled in real time to guarantee the practical security of the CV-MDI QKD system. Here we propose a countermeasure for negative impact introduced by the actual source in the CV-MDI QKD system based on one-time-calibration method, not only eliminating the loophole induced from the relative intensity noise (RIN) which is part of the source noise, but also modeling the source noise thus improving the performance. In particular, three cases in terms of whether the preparation noise of the practical sources are defined or not, where only one of the users or both two users operate monitoring on their respective source outputs, are investigated. The simulation results show that the estimated secret key rate without our proposed scheme are about 10.7 times higher than the realistic rate at 18 km transmission distance when the variance of RIN is only 0.4. What's worse, the difference becomes greater and greater with the increase of the variance of RIN. Thus, our proposed scheme makes sense in further completing the practical security of CV-MDI QKD system. In other words, our work enables CV-MDI QKD system not only to resist all attacks against detectors, but also to close the vulnerability caused by the actual source, thus making the scheme closer to practical security

    Identifying and analysing the factors influencing the livelihood strategy choices of rural households

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    Identifying the influence factors lie behind the livelihood choices of rural households are of crucial significance for improving the sustainable livelihoods of rural households in tourism regions. Five villages in Sa Pa District, Vietnam, were selected in this study, to conduct household surveys and interviews with 180 households. Based on this, a comprehensive approach, which includes multinomial/binary logistic regression, Ripley’s function, and geographical detector, is applied to understand the households’ capital endowment and factors lie behind their livelihood choices. Results show that for rural households, tourism livelihood yields the highest income, but the lack of diversity of livelihood activities may make tourism livelihood household more vulnerable to the external risk and shocks than balanced livelihood households. Different types of households are found to show clustering feature, with clustering degree ranking as: agricultural > balanced > tourism > labour. Households with more natural capital are less likely to choose livelihoods other than agriculture livelihood. And households with more financial capital are less likely to engage in agricultural livelihood. Both financial capital and social capital can facilitate engagement in balanced livelihood. And financial capital is key to tourism livelihood, and a barrier impeding agricultural households to participate in other livelihood activities

    Design of the offline test electronics for the nozzle system of proton therapy

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    A set of nozzle equipment for proton therapy is now being developed at China Institute of Atomic Energy. To facilitate the off-line commissioning of the whole equipment, a set of ionization chamber signal generation system, the test electronics, is designed. The system uses ZYNQ SoC as the main control unit and outputs the beam dose analog signal through DAC8532. The dual SPDT analog switch, DG636, is used to simulate the beam position signals according to Gaussian distribution. The results show that the system can simulate the beam position, dose, and other related analog signals generated by the proton beam when passing through the ionization chamber. Moreover, the accuracy of the simulated beam position is within +/-0.33mm, and the accuracy of the simulated dose signal is within +/-1%. At the same time, it can output analog signals representing environmental parameters. The test electronics meets the design requirements, which can be used to commission the nozzle system as well as the treatment control system without the proton beam

    Clinical thought-based software for diagnosing developmental dysplasia of the hip on pediatric pelvic radiographs

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    BackgroundThe common methods of radiographic diagnosis of developmental dysplasia of the hip (DDH) include measuring hip parameters and quantifying the degree of hip dislocation. However, clinical thought-based analysis of hip parameters may be a more effective way to achieve expert-like diagnoses of DDH. This study aims to develop a diagnostic strategy-based software for pediatric DDH and validate its clinical feasibility.MethodsIn total, 543 anteroposterior pelvic radiographs were retrospectively collected from January 2017 to December 2021. Two independent clinicians measured four diagnostic indices to compare the diagnoses made by the software and conventional manual method. The diagnostic accuracy was evaluated using the receiver operator characteristic (ROC) curves and confusion matrix, and the consistency of parametric measurements was assessed using Bland-Altman plots.ResultsIn 543 cases (1,086 hips), the area under the curve, accuracy, sensitivity, and specificity of the software for diagnosing DDH were 0.988–0.994, 99.08%–99.72%, 98.07%–100.00%, and 99.59%, respectively. Compared with the expert panel, the Bland-Altman 95% limits of agreement for the acetabular index, as determined by the software, were −2.09°–2.91° (junior orthopedist) and −1.98°–2.72° (intermediate orthopedist). As for the lateral center-edge angle, the 95% limits were −3.68°–5.28° (junior orthopedist) and −2.94°–4.59° (intermediate orthopedist).ConclusionsThe software can provide expert-like analysis of pelvic radiographs and obtain the radiographic diagnosis of pediatric DDH with great consistency and efficiency. Its initial success lays the groundwork for developing a full-intelligent comprehensive diagnostic system of DDH

    2-Deoxyglucose alleviates migraine-related behaviors by modulating microglial inflammatory factors in experimental model of migraine

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    BackgroundTargeting metabolic pathways has emerged as a new migraine treatment strategy as researchers realize the critical role metabolism plays in migraine. Activated inflammatory cells undergo metabolic reprogramming and rely on glycolysis to function. The objective of this study was to investigate the glycolysis changes in the experimental model of migraine and the effect of glycolysis inhibitor 2-Deoxy-D-glucose (2-DG) in the pathophysiology of migraine.MethodsWe used a rat model of migraine that triggered migraine attacks by applying inflammatory soup (IS) to the dura and examined changes in glycolysis. 2-DG was used to inhibit glycolysis, and the effects of 2-DG on mechanical ectopic pain, microglial cell activation, calcitonin gene-related peptides (CGRP), c-Fos, and inflammatory factors induced by inflammatory soup were observed. LPS stimulated BV2 cells to establish a model in vitro to observe the effects of 2-DG on brain-derived neurotrophic factor (BDNF) after microglia activation.ResultsIn the experimental model of migraine, key enzymes involved in glycolysis such as phosphofructokinase platelet (PFKP), hexokinase (HK2), hypoxia inducible factor-1α (HIF-1α), lactate dehydrogenase (LDH) and pyruvate kinase (PKM2) were expressed in the medullary dorsal horn. While the expression of electronic respiratory transport chain complex IV (COXIV) decreased. There were no significant changes in glucose 6-phosphate dehydrogenase (G6PD), a key enzyme in the pentose phosphate pathway. The glycolysis inhibitor 2-DG alleviated migraine-like symptoms in an experimental model of migraine, reduced the release of proinflammatory cytokines caused by microglia activation, and decreased the expression of CGRP and c-Fos. Further experiments in vitro demonstrated that glycolysis inhibition can reduce the release of Iba-1/proBDNF/BDNF and inhibit the activation of microglia.ConclusionThe migraine rat model showed enhanced glycolysis. This study suggests that glycolytic inhibitor 2-DG is an effective strategy for alleviating migraine-like symptoms. Glycolysis inhibition may be a new target for migraine treatment
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