181 research outputs found

    Infinite Horizon Mean-Field Linear Quadratic Optimal Control Problems with Jumps and the related Hamiltonian Systems

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    In this work, we focus on an infinite horizon mean-field linear-quadratic stochastic control problem with jumps. Firstly, the infinite horizon linear mean-field stochastic differential equations and backward stochastic differential equations with jumps are studied to support the research of the control problem. The global integrability properties of their solution processes are studied by introducing a kind of so-called dissipation conditions suitable for the systems involving the mean-field terms and jumps. For the control problem, we conclude a sufficient and necessary condition of open-loop optimal control by the variational approach. Besides, a kind of infinite horizon fully coupled linear mean-field forward-backward stochastic differential equations with jumps is studied by using the method of continuation. Such a research makes the characterization of the open-loop optimal controls more straightforward and complete.Comment: 27page

    A Comparative Analysis of the Determinants of Risk and Performance in Chinese and UK Banks

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    Driven largely by the recent financial crisis and accounting standards, the performance of banks and its risk have received increasing attention especially in the banking sector. Focusing on how well the bank could perform after the strike of financial crisis and how much they put attention to risk management, this study provides insights on determinants of a bank’s performance and risk of a sample of UK and Chinese banks for the examined year from 2007 to 2017 following the adoption of Basel III. Using the hypotheses tests and multivariate regression model, appropriate models were chosen for evaluating bank performance and bank risk and then potential relationships between determinants were examined. The finding reveals that Chinese banks have a better performance in avoiding negative outcomes from financial crisis than that of UK banks while UK banking system put much attention to risk preparation. Corresponding suggestions were raised in order to help two countries overcome the obstacle from financial crisis. Keywords: bank performance; bank risk; financial crisis; Basel III; regression analysi

    Intelligent Control and Parameter Calculation of Highway Truck Escape Ramp

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    To reduce the probability of secondary accidents caused by the direction deviation, body rollover, and excessive deceleration of runaway vehicles during braking on a truck escape ramp (TER), the safety of the occupants and the vehicles must be ensured. Based on the momentum theorem, an intelligent control method for a TER is proposed. In the method, a slope aggregate with a small rolling resistance coefficient is used on the original escape lane, and the information acquisition, braking device control, and braking modules are established. Through these modules, the operation parameters and control parameters of the out-of-control vehicle are obtained in advance, to control the operation state of the runaway vehicle. Achieve the purpose of reducing the braking effect of the slope bed aggregate and ensuring maximum utilization of the braking ramp. Finally, the proposed control method is simulated on the MATLAB/Simulink simulation platform. The results show that the control method can realize safe braking of an out-of-control vehicle at various speeds and different mass conditions, and it can play a highly significant role in the braking of high-speed and heavy-duty vehicles

    Genetic diversity and selection of three nuclear genes in Schistosoma japonicum populations

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    Background: The blood fluke, Schistosoma japonicum still causes severe disease in China, the Philippines and Indonesia. Although there have been some studies the molecular epidemiology of this persistent and harmful parasite, few have explored the possibility and implications of selection in S. japonicum populations. Methods: We analyzed diversity and looked for evidence of selection at three nuclear genes (SjIpp2, SjFabp and SjT22.6) in 13 S. japonicum populations. Results: SjT22.6 was found to exhibit high nucleotide diversity and was under positive selection in the mountainous region of mainland China. As a tegumental protein, its secondary and tertiary structure differed between S. japonicum strains from the mountainous and lakes regions. In contrast, SjIpp2 and SjFabp had relatively low levels of nucleotide diversity and did not show significant departure from neutrality. Conclusions: As a tegument-associated antigen-encoding gene of S. japonicum, SjT22.6 has high nucleotide diversity and appears to be under positive selection in the mountainous region of mainland China

    Clinicopathological analysis of DLBCL/HGBL with MYC, BCL2 and BCL6 gene rearrangement

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    Background and purpose: Diffuse large B-cell lymphoma/high-grade B-cell lymphoma (DLBCL/HGBL) with gene rearrangement of MYC, BCL2 and BCL6, also known as triple-hit lymphoma (THL), has a low incidence and relevant literature is limited. Thus comprehensive and sufficient understanding is lacking. The purpose of this study was to explore the clinicopathological features and prognosis of this rare disease. Methods: Ten cases of THL diagnosed in Department of Pathology, Fudan University Shanghai Cancer Center from June 2016 to December 2021 were collected. Clinical features were analyzed retrospectively. Histopathological features were observed using H-E stain. Immunophenotype was analyzed by immunohistochemistry. The rearrangement of MYC, BCL2 and BCL6 genes was detected by fluorescence in situ hybridization (FISH), and Epstein-Barr virus (EBV) infection was detected by in situ hybridization using EBV-encoded RNA (EBER). Results: Of the 10 cases, 4 cases were male and 6 cases were female. The median age was 54 years (43-80 years). Two cases occurred in lymph nodes, 6 cases involved extranodal organs, and both lymph nodes and extranodal organs were involved in the other 2 cases. There were 4 cases (40%) with clinical stage Ⅲ/Ⅳ disease and 6 cases (60%) with clinical stage Ⅰ/Ⅱ disease. 40% (4/10) patients had international prognostic index (IPI) score ≥3. 50% (4/8) patients had bone marrow invasion. Two (20%) cases had B symptoms. 40% (4/10) patients had a history of hepatitis B virus infection. Five cases had the morphology of DLBCL, not otherwise specified (DLBCL-NOS); Two cases showed morphological features intermediate both DLBCL and Burkitt lymphoma; One case had a blastoid cytomorphology, and the other 2 cases failed to be classified accurately because of serious crushing artifacts of the tissue. Immunophenotypically, 80% of the cases were of germinal center B-cell (GCB) type and 20% were of non-GCB type. MYC/BCL2 double expression accounted for 78% (7/9), BCL6 positivity was found in 80% of the total cases, and the Ki-67 proliferation index was ≥80% in all cases. FISH showed that all 10 cases had MYC, BCL2 and BCL6 gene translocation rearrangement. EBV infection was consistently absent. All except one case received systemic treatment. The overall survival was 2.0-55.5 months (median, 16.8 months), and 1-year overall survival rate was 68.6%. The 1-year overall survival rates of patients with stage Ⅰ/Ⅱ disease and stage Ⅲ/Ⅳ disease were 100% and 25% respectively. Conclusion: THL mainly affects middle-aged and elderly patients, which occured more frequently in extranodal organs, and it is characterized by GCB immunophenotype and MYC/BCL2 double expression. A considerable number of patients have a clinical stage of Ⅰ/Ⅱ disease and a better prognosis in the current series, indicating that early identification of THL is of great importance for timely intervention and improving the prognosis

    Identification and characterization of the highly polymorphic locus D14S739 in the Han Chinese population

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    Aim To systemically select and evaluate short tandem repeats (STRs) on the chromosome 14 and obtain new STR loci as expanded genotyping markers for forensic application. Methods STRs on the chromosome 14 were filtered from Tandem Repeats Database and further selected based on their positions on the chromosome, repeat patterns of the core sequences, sequence homology of the flanking regions, and suitability of flanking regions in primer design. The STR locus with the highest heterozygosity and polymorphism information content (PIC) was selected for further analysis of genetic polymorphism, forensic parameters, and the core sequence. Results Among 26 STR loci selected as candidates, D14S739 had the highest heterozygosity (0.8691) and PIC (0.8432), and showed no deviation from the Hardy-Weinberg equilibrium. 14 alleles were observed, ranging in size from 21 to 34 tetranucleotide units in the core region of (GATA)9-18 (GACA)7-12 GACG (GACA)2 GATA. Paternity testing showed no mutations. Conclusion D14S739 is a highly informative STR locus and could be a suitable genetic marker for forensic applications in the Han Chinese populatio

    Automatic segmentation of white matter hyperintensities in routine clinical brain MRI by 2D VB-Net: A large-scale study

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    White matter hyperintensities (WMH) are imaging manifestations frequently observed in various neurological disorders, yet the clinical application of WMH quantification is limited. In this study, we designed a series of dedicated WMH labeling protocols and proposed a convolutional neural network named 2D VB-Net for the segmentation of WMH and other coexisting intracranial lesions based on a large dataset of 1,045 subjects across various demographics and multiple scanners using 2D thick-slice protocols that are more commonly applied in clinical practice. Using our labeling pipeline, the Dice consistency of the WMH regions manually depicted by two observers was 0.878, which formed a solid basis for the development and evaluation of the automatic segmentation system. The proposed algorithm outperformed other state-of-the-art methods (uResNet, 3D V-Net and Visual Geometry Group network) in the segmentation of WMH and other coexisting intracranial lesions and was well validated on datasets with thick-slice magnetic resonance (MR) images and the 2017 medical image computing and computer assisted intervention WMH Segmentation Challenge dataset (with thin-slice MR images), all showing excellent effectiveness. Furthermore, our method can subclassify WMH to display the WMH distributions and is very lightweight. Additionally, in terms of correlation to visual rating scores, our algorithm showed excellent consistency with the manual delineations and was overall better than those from other competing methods. In conclusion, we developed an automatic WMH quantification framework for multiple application scenarios, exhibiting a promising future in clinical practice

    Estimating cancer incidence based on claims data from medical insurance systems in two areas lacking cancer registries in China.

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    BACKGROUND: We aimed to establish a Medical-Insurance-System-based Cancer Surveillance System (MIS-CASS) in China and evaluate the completeness and timeliness of this system through reporting cancer incidence rates using claims data in two regions in northern and southern China. METHODS: We extracted claims data from medical insurance systems in Hua County of Henan Province, and Shantou City in Guangdong Province in China from Jan 1, 2012 to Jun 30, 2019. These two regions have been considered to be high risk regions for oesophageal cancer. We developed a rigorous procedure to establish the MIS-CASS, which includes data extraction, cleaning, processing, case ascertainment, privacy protection, etc. Text-based diagnosis in conjunction with ICD-10 codes were used to determine cancer diagnosis. FINDINGS: In 2018, the overall age-standardised (Segi population) incidence rates (ASR World) of cancer in Hua County and Shantou City were 167·39/100,000 and 159·78/100,000 respectively. In both of these areas, lung cancer and breast cancer were the most common cancers in males and females respectively. Hua County is a high-risk region for oesophageal cancer (ASR World: 25·95/100,000), whereas Shantou City is not a high-risk region for oesophageal cancer (ASR World: 11·43/100,000). However, Nanao island had the highest incidence of oesophageal cancer among all districts and counties in Shantou (ASR World: 36·39/100,000). The age-standardised male-to-female ratio for oesophageal cancer was lower in Hua County than in Shantou (1·69 vs. 4·02). A six-month lag time was needed to report these cancer incidences for the MIS-CASS. INTERPRETATION: MIS-CASS efficiently reflects cancer burden in real-time, and has the potential to provide insight for improvement of cancer surveillance in China. FUNDING: The National Key R&D Program of China (2016YFC0901404), the Digestive Medical Coordinated Development Center of Beijing Municipal Administration of Hospitals (XXZ0204), the Sanming Project of Shenzhen (SZSM201612061), and the Shantou Science and Technology Bureau (190829105556145, 180918114960704)
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