Where is VALDO? VAscular Lesions Detection and segmentatiOn challenge at MICCAI 2021

Imaging markers of cerebral small vessel disease provide valuable information on brain health, but their manual assessment is time-consuming and hampered by substantial intra- and interrater variability. Automated rating may benefit biomedical research, as well as clinical assessment, but diagnostic reliability of existing algorithms is unknown. Here, we present the results of the VAscular Lesions DetectiOn and Segmentation (Where is VALDO?) challenge that was run as a satellite event at the international conference on Medical Image Computing and Computer Aided Intervention (MICCAI) 2021. This challenge aimed to promote the development of methods for automated detection and segmentation of small and sparse imaging markers of cerebral small vessel disease, namely enlarged perivascular spaces (EPVS) (Task 1), cerebral microbleeds (Task 2) and lacunes of presumed vascular origin (Task 3) while leveraging weak and noisy labels. Overall, 12 teams participated in the challenge proposing solutions for one or more tasks (4 for Task 1-EPVS, 9 for Task 2-Microbleeds and 6 for Task 3-Lacunes). Multi-cohort data was used in both training and evaluation. Results showed a large variability in performance both across teams and across tasks, with promising results notably for Task 1-EPVS and Task 2-Microbleeds and not practically useful results yet for Task 3-Lacunes. It also highlighted the performance inconsistency across cases that may deter use at an individual level, while still proving useful at a population level

A Hardy Inequality with Remainder Terms in the Heisenberg Group and the Weighted Eigenvalue Problem

Based on properties of vector fields, we prove Hardy inequalities with remainder terms in the Heisenberg group and a compact embedding in weighted Sobolev spaces. The best constants in Hardy inequalities are determined. Then we discuss the existence of solutions for the nonlinear eigenvalue problems in the Heisenberg group with weights for the -sub-Laplacian. The asymptotic behaviour, simplicity, and isolation of the first eigenvalue are also considered.</p

Application of Long Noncoding RNAs in Osteosarcoma: Biomarkers and Therapeutic Targets

Osteosarcoma is the most common primary bone malignancy in children and adolescents. Although improvements in therapeutic strategies were achieved, the outcome remains poor for most patients with metastatic or recurrent osteosarcoma. Therefore, it is imperative to identify novel and effective prognostic biomarker and therapeutic targets for the disease. Long noncoding RNAs (lncRNAs) are a novel class of RNA molecules defined as transcripts &#x3e;200 nucleotides that lack protein coding potential. Many lncRNAs are deregulated in cancer and are important regulators for malignancies. Nine lncRNAs (91H, BCAR4, FGFR3-AS1, HIF2PUT, HOTTIP, HULC, MALAT-1, TUG1, UCA1) are upregulated and considered oncogenic for osteosarcoma. Loc285194 and MEG3 are two lncRNAs downregulated and as tumor suppressor for the disease. Moreover, the expressions of LINC00161 and ODRUL are associated with chemo-resistance of osteosarcoma. The mechanisms for these lncRNAs in regulating development of osteosarcoma are diverse, e.g. ceRNA, Wnt/β-catenin pathway, etc. The lncRNAs identified may serve as potential biomarkers or therapeutic targets for osteosarcoma

Information Asymmetry and the Debt Contracting Demand for Accounting Conservatism

We show analytically and empirically that the relation between conservatism and covenants is conditioned on the extent of information asymmetry between borrowers and lenders. In particular, when the degree of information asymmetry is high, conservatism and covenants complement each other to signal potential wealth transfers from debt holders to equity holders. No such a relation obtains when the degree of information asymmetry is low. We further show that under a high information asymmetry regime, borrowers with a high level of conservatism and tight covenants generally enjoy lower interest rates than borrowers with a low level of conservatism and loose covenants. Consistent with our signaling theory, we also document that borrowers with a high level of conservatism and tight covenants in the high information asymmetry regime are less likely to make future wealth transfers from creditors to equity holders. Our empirical results are fairly robust to alternative measures of conservatism and covenant restrictiveness

Research on the deformation mechanism and ACC control technology of gob‐side roadway in an extra‐thick coal seam with varying thickness

Abstract To improve the extraction of coal resources, gob‐side entry driving is gradually being promoted and applied. However, as the thickness of the coal seam increases, the deformation control of the roadway becomes more difficult. Aiming at this problem, a combination of theoretical calculation, numerical simulation, and field test was used to analyze the aspects of the stress environment, surrounding rock properties, and support forms. The phenomenon and mechanization of intensified deformation and failure of roadway with increasing coal seam thickness were revealed. The specific results include: (1) The ratio of principal stress at the excavation position controls the maximum failure depth of roadway, and the direction of principal stress determines the location of the maximum failure depth; (2) As the thickness of the coal seam increases, the properties of the surrounding rock at the excavation position decrease, the principal stress ratio increases, and the deflection angle of the principal stress increases, which lead to an intensification of the deformation and failure of the roadway. Based on the deformation and failure characteristics of the roadway and the shortcomings of the original support form, a control strategy and support scheme based on a new support structure called “Anchor Cable with C‐shaped Tube” is proposed, which has achieved better deformation control effect in on‐site application