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Abstract-Internet routers today can be overwhelmed by a large number of BGP updates triggered by events such as session resets, link failures, and policy changes. Such excessive updates can delay routing convergence, which, in turn, degrades the performance of delay-and jitter-sensitive applications. This paper proposes a simple and novel idea of differentiated processing of BGP updates to reduce routers' load and improve routing convergence without changing the protocol semantics. Based on a set of criteria, BGP updates are grouped into different priority classes. Higher-priority updates are processed and propagated sooner, while lower-priority ones, not affecting routing decisions, can be delayed to both reduce routers' load and improve routing convergence. We first present a general methodology for update classification, update processing, and priority-state inference. By analyzing real BGP data obtained from Route Views, we show that our update classification is feasible and beneficial. We further propose two differentiated update processing (DUP) algorithms and evaluate them using the SSFNet BGP simulator on several realistic network topologies. The algorithms are shown to be very effective for large networks, yielding 30% fewer updates and reducing convergence time by 80%. Our scheme is simple and light-weight with little added processing overhead. It can be deployed incrementally, since BGP messages are not modified and every BGP router makes routing decisions independently.

Introduction Bile acid diarrhoea (BAD) can occur due to disruption to the enterohepatic circulation, e.g. following cholecystectomy. Post-cholecystectomy diarrhoea has been reported in 2.1–57.2% of patients; however, this is not necessarily due to BAD. The aim of this study was to determine the rates of bile acid diarrhoea diagnosis after cholecystectomy and to consider investigation practices. Methods A retrospective analysis of electronic databases from five large centres detailing patients who underwent laparoscopic cholecystectomy between 2013 and 2017 was cross-referenced with a list of patients who underwent 75SeHCAT testing. A 7-day retention time of <15% was deemed to be positive. Patient demographics and time from surgery to investigation were collected and compared for significance (p < 0.05). Results A total of 9439 patients underwent a laparoscopic cholecystectomy between 1 January 2013 and 31 December 2017 in the five centres. In total, 202 patients (2.1%) underwent investigation for diarrhoea via 75SeHCAT, of which 64 patients (31.6%) had a 75SeHCAT test result of >15%, while 62.8% of those investigated were diagnosed with bile acid diarrhoea (BAD). In total, 133 (65.8%) patients also underwent endoscopy and 74 (36.6%) patients had a CT scan. Median time from surgery to 75SeHCAT test was 672 days (SD ± 482 days). Discussion/Conclusion Only a small proportion of patients, post-cholecystectomy, were investigated for diarrhoea with significant time delay to diagnosis. The true prevalence of BAD after cholecystectomy may be much higher, and clinicians need to have an increased awareness of this condition due to its amenability to treatment. 75SeHCAT is a useful tool for diagnosis of bile acid diarrhoea.

Carbon tetrachloride (CCl4), Concanavalin A (ConA), bile duct ligation (BDL), and liver resection (LR) are four types of commonly used mouse models of acute liver injury. However, these four models belong to different types of liver cell damage while their application situations are often confounded. In addition, the systematic changes of multiple extra-liver organs after acute liver injury and the crosstalk between liver and extra-liver organs remain unclear. Here, we aim to map the morphological, metabolomic and transcriptomic changes systematically after acute liver injury and search for the potential crosstalk between the liver and the extra-liver organs. Significant changes of transcriptome were observed in multiple extra-liver organs after different types of acute liver injury despite dramatic morphological damage only occurred in lung tissues of the ConA/BDL models and spleen tissues in the ConA model. Liver transcriptomic changes initiated the serum metabolomic alterations which correlated to transcriptomic variation in lung, kidney, and brain tissues of BDL and LR models. The potential crosstalk might lead to pulmonary damage and development of hepatorenal syndrome (HRS) and hepatic encephalopathy (HE) during liver injury. Serum derived from acute liver injury mice damaged alveolar epithelial cells and human podocytes in vitro. Our data indicated that different types of acute liver injury led to different transcriptomic changes within extra-liver organs. Integration of serum metabolomics and transcriptomics from multiple tissues can improve our understanding of acute liver injury and its effect on the other organs.

Objective:We aimed to quantitatively evaluate the degree of endolymphatic hydrops and its correlation with the clinical features of Meniere's disease. Methods:We retrospectively collected data from patients with Meniere's disease who underwent gadolinium-enhanced magnetic resonance imaging (MRI) at our department from January 2018 to December 2019. Mimics software was used to perform three-dimensional modelling of the labyrinth, and volume information was obtained to calculate the endolymphatic hydrops index (EHI). A correlation analysis was conducted with data from pure tone audiometry, electrocochleography (EchoG), vestibular myogenic-evoked potential (VEMP) testing, caloric testing and video head impulse testing (vHIT). A two-dimensional method was also employed to calculate the hydrops ratio (HR) of cochlea and vestibule. The test-retest reliability of EHI/HR from different operators was evaluated.Results: A total of 23 affected ears were examined, and the EHI was significantly correlated with Meniere's disease stage, low-frequency hearing threshold, EchoG summating potential/action potential ratio (−SP/AP) and VEMP binaural asymmetry ratio, but no significant correlation was observed between EHI and the caloric test or vHIT.The Intraclass correlation coefficient (ICC) of EHI data calculated by two otologists was 0.946 (p < .001). And the ICC of cochlea and vestibule HR were 0.844 and 0.832 (p < .001). Conclusion:Mimics software can be used to quantitatively evaluate the degree of endolymphatic hydrops and have shown higher test-retest reliability than traditional two-dimensional evaluation method. Endolymphatic hydrops correlates with clinical data, such as Meniere's disease stage, low-frequency hearing threshold, EchoG and VEMP asymmetry ratio.