4,910 research outputs found

    The roles of endoglin gene in cerebrovascular diseases.

    Get PDF
    Endoglin (ENG, also known as CD105) is a transforming growth factor β (TGFβ) associated receptor and is required for both vasculogenesis and angiogenesis. Angiogenesis is important in the development of cerebral vasculature and in the pathogenesis of cerebral vascular diseases. ENG is an essential component of the endothelial nitric oxide synthase activation complex. Animal studies showed that ENG deficiency impairs stroke recovery. ENG deficiency also impairs the regulation of vascular tone, which contributes to the pathogenesis of brain arteriovenous malformation (bAVM) and vasospasm. In human, functional haploinsufficiency of ENG gene causes type I hereditary hemorrhagic telangiectasia (HHT1), an autosomal dominant disorder. Compared to normal population, HHT1 patients have a higher prevalence of AVM in multiple organs including the brain. Vessels in bAVM are fragile and tend to rupture, causing hemorrhagic stroke. High prevalence of pulmonary AVM in HHT1 patients are associated with a higher incidence of paradoxical embolism in the cerebral circulation causing ischemic brain injury. Therefore, HHT1 patients are at risk for both hemorrhagic and ischemic stroke. This review summarizes the possible mechanism of ENG in the pathogenesis of cerebrovascular diseases in experimental animal models and in patients

    Discovering New Intents with Deep Aligned Clustering

    Full text link
    Discovering new intents is a crucial task in dialogue systems. Most existing methods are limited in transferring the prior knowledge from known intents to new intents. They also have difficulties in providing high-quality supervised signals to learn clustering-friendly features for grouping unlabeled intents. In this work, we propose an effective method, Deep Aligned Clustering, to discover new intents with the aid of the limited known intent data. Firstly, we leverage a few labeled known intent samples as prior knowledge to pre-train the model. Then, we perform k-means to produce cluster assignments as pseudo-labels. Moreover, we propose an alignment strategy to tackle the label inconsistency problem during clustering assignments. Finally, we learn the intent representations under the supervision of the aligned pseudo-labels. With an unknown number of new intents, we predict the number of intent categories by eliminating low-confidence intent-wise clusters. Extensive experiments on two benchmark datasets show that our method is more robust and achieves substantial improvements over the state-of-the-art methods. The codes are released at https://github.com/thuiar/DeepAligned-Clustering.Comment: Accepted by AAAI 2021 (Main Track, Long Paper

    Clinical observation on fibrin glue technique in pterygium surgery performed with limbal autograft transplantation

    Get PDF
    AIM: To compare the efficiency and safety of fibrin glue to suture technique in pterygium surgery performed with limbal autograft.<p>METHODS: A prospective randomized clinical trial was carried out in 60 eyes of 48 patients operated for primary nasal pterygium. Autologous limbal graft taken from the superotemporal limbus was used to cover the sclera after pterygium excision under local anesthesia with 2% lidocaine. In 22 cases(30 eyes), the transplant was attached to the sclera with a fibrin tissue adhesive(group 1)and in 26 cases(30 eyes)with 10-0 Virgin silk sutures(group 2). Patients were followed up at least for 3 months. Time of operation, matching degree of graft and visual analogue scale(VAS)score were mainly observed and recorded. <p>RESULTS: Patient symptoms were significantly less and biomicroscopic findings were better in group 1. Pterygium recurrence was seen in 1 case of group 1, and 1 case of group 2. Average surgery time was shorter(<i>P</i><0.01)in fibrin group. <p>CONCLUSION: Using fibrin glue for graft fixation in pterygium surgery causes significantly less postoperative pain and shortens surgery time significantly

    Watertightization of Trimmed Surfaces at Intersection Boundary

    Full text link
    This paper introduces a watertight technique to deal with the boundary representation of surface-surface intersection in CAD. Surfaces play an important role in today's geometric design. The mathematical model of non-uniform rational B-spline surfaces (NURBS) is the mainstream and ISO standard. In the situation of surface-surface intersection, things are a little complicated, for some parts of surfaces may be cut-off, so called trimmed surfaces occur, which is the central topic in the past decades in CAD community of both academia and industry. The main problem is that the parametric domain of the trimmed surface generally is not the standard square or rectangle, and rather, typically, bounded by curves, based on point inverse of the intersection points and interpolated. The existence of gaps or overlaps at the intersection boundary makes hard the preprocessing of CAE and other downstream applications. The NURBS are in this case hard to keep a closed form. In common, a special data structure of intersection curves must be affiliated to support downstream applications, while the data structure of the whole CAD system is not unified, and the calculation is not efficient. In terms of Bezier surface, a special case of NURBS, this paper designs a reparameterization or normalization to transform the trimmed surface into a group of Bezier surface patches in standard parametric domain [0,1]X[0,1]. And then the boundary curve of normalized Bezier surface patch can be replaced by the intersection curve to realize watertight along the boundary. In this way, the trimmed surface is wiped out, the "gap" between CAD and CAE is closed.Comment: 10 pages,6 figure

    Can onshore spot market progress influence offshore N.D.F. market development for the C.N.Y?

    Get PDF
    This study utilises a time-varying wavelet analysis to examine the relationship between the onshore spot market and the offshore non-deliverable forward (N.D.F.) market of the Chinese Yuan (C.N.Y.). Given the presence of structural changes in the two markets, we did not find any stable causality during the sample period. However, in some sub-samples, we found that there is a strong nonlinear causal relationship running from the onshore spot market to the offshore N.D.F. market. Ties between the two markets are closer after the widening of the onshore trading band, first in April 2012, second in March 2014 and again in August 2015. The onshore spot market is heavily influenced by interventions by the People’s Bank of China (P.B.C.). These findings imply that offshore N.D.F. market development is not divorced from onshore development, as developments in the onshore spot market influence the offshore N.D.F. market. The results show that the exchange rate markets for the C.N.Y. are not efficient. Thus, to successfully internationalise the C.N.Y., financial expansion of the onshore spot market should keep pace with the growing offshore N.D.F. market to minimise destabilisation of the C.N.Y
    corecore