650 research outputs found

    Primary isolated intracranial Rosai–Dorfman disease: Report of a rare case and review of the literature

    Get PDF
    Background Intracranial involvement is an uncommon manifestation of Rosai–Dorfman disease (RDD) and had been rarely reported. In this study, we explore clinical characteristics, imageology manifestations and pathological features of primary intracranial RDD so as to improve the understanding for this disease. Methods One case (16-years-old boy) with primary intracranial RDD was analyzed and studied retrospectively by MRI features, histopathological observation and immunohistochemical staining, and the related literatures were reviewed. Results The case was single lesion and involved the dura of the left middle cranial fossa base, which was iso-hypo signal intensity on T1WI and hypointense on T2WI and FLAIR image. The lesion was a homogeneous contrast enhancement mass with dural tail sign and had peritumoral brain edema. Pathological analysis showed the lesion consisted of variable numbers of mature lymphocytes, plasma cells and neutrophils. The characteristic histiocytes were emperipolesis and positively expressed for S-100 and CD-68 and negatively expressed for CD-1a by immunohistochemical analysis. Based on clinical presentations and histological findings after surgical excision, a final diagnosis of primary intracranial RDD was made. Conclusion Primary intracranial RDD, especially located in the cranial base, is exceptionally rare, which hard to be distinguished with meningoma by imageology and clinical manifestations, but could be diagnosed by pathological and immunohistochemical examinations. Surgery is of the most importance treatment and prognosis is optimistic for this disease

    Experimental Research and Theoretical Analysis on Throttling Characteristics of Electronic Expansion Valve in Series with Capillary Tube

    Get PDF
    The mass flow rate of R-32 and volumetric flow rate of dry air in an electronic expansion valves(EEV) , in two different capillary tubes(CT) and in one expansion valve in series with two different capillary tubes were tested, and the theoretical volumetric flow rate of dry air in one EEV in series with different CTs were predicted through a theoretical throttling model built in this paper. The results showed that the mass flow rate of R-32 or volumetric flow rate of dry air of the serial throttling component was lower than but close to that of the EEV in low openings and that of the CT in full opening, respectively, under the same operating conditions. The flow rate ratio of the serial throttling component to the EEV decreased fast with opening increasing, and the flow rate ratio of the refrigerant was obviously lower than that of the dry air. The refrigerant mass flow rate of EEV in series with CT up flow was higher than that of the same EEV in series with the same CT down flow

    A Conditioned Behavioral Paradigm for Assessing Onset and Lasting Tinnitus in Rats

    Get PDF
    Numerous behavioral paradigms have been developed to assess tinnitus-like behavior in animals. Nevertheless, they are often limited by prolonged training requirements, as well as an inability to simultaneously assess onset and lasting tinnitus behavior, tinnitus pitch or duration, or tinnitus presence without grouping data from multiple animals or testing sessions. To enhance behavioral testing of tinnitus, we developed a conditioned licking suppression paradigm to determine the pitch(s) of both onset and lasting tinnitus-like behavior within individual animals. Rats learned to lick water during broadband or narrowband noises, and to suppress licking to avoid footshocks during silence. After noise exposure, rats significantly increased licking during silent trials, suggesting onset tinnitus-like behavior. Lasting tinnitus-behavior, however, was exhibited in about half of noise-exposed rats through 7 weeks post-exposure tested. Licking activity during narrowband sound trials remained unchanged following noise exposure, while ABR hearing thresholds fully recovered and were comparable between tinnitus(+) and tinnitus(-) rats. To assess another tinnitus inducer, rats were injected with sodium salicylate. They demonstrated high pitch tinnitus-like behavior, but later recovered by 5 days post-injection. Further control studies showed that 1): sham noise-exposed rats tested with footshock did not exhibit tinnitus-like behavior, and 2): noise-exposed or sham rats tested without footshocks showed no fundamental changes in behavior compared to those tested with shocks. Together, these results demonstrate that this paradigm can efficiently test the development of noise- and salicylate-induced tinnitus behavior. The ability to assess tinnitus individually, over time, and without averaging data enables us to realistically address tinnitus in a clinically relevant way. Thus, we believe that this optimized behavioral paradigm will facilitate investigations into the mechanisms of tinnitus and development of effective treatments

    Application and Exploration of FLUENT Software in the Teaching of Engineering Thermophysics

    Get PDF
    Engineering thermophysics is a basic discipline for energy majors, but this course emphasizes the theoretical level and is difficult to understand. Students\u27 enthusiasm and participation in the learning process are low, and it is difficult to understand the course. Accordingly, the research team attempts to introduce Fluent software into the course teaching exploration. Specifically, Fluent software is adopted to provide a reliable physics teaching model, and to change the traditional teaching mode, so as to improve students\u27 daily learning ability and practical ability, and ultimately enable students to learn and practice

    MU-ORAM: Dealing with Stealthy Privacy Attacks in Multi-User Data Outsourcing Services

    Get PDF
    Outsourcing data to remote storage servers has become more and more popular, but the related security and privacy concerns have also been raised. To protect the pattern in which a user accesses the outsourced data, various oblivious RAM (ORAM) constructions have been designed. However, when existing ORAM designs are extended to support multi-user scenarios, they become vulnerable to stealthy privacy attacks targeted at revealing the data access patterns of innocent users, even if only one curious or compromised user colludes with the storage server. To study the feasibility and costs of overcoming the above limitation, this paper proposes a new ORAM construction called Multi-User ORAM (MU-ORAM), which is resilient to stealthy privacy attacks. The key ideas in the design are (i) introduce a chain of proxies to act as a common interface between users and the storage server, (ii) distribute the shares of the system secrets delicately to the proxies and users, and (iii) enable a user and/or the proxies to collaboratively query and shuffle data. Through extensive security analysis, we quantify the strength of MU-ORAM in protecting the data access patterns of innocent users from attacks, under the assumption that the server, users, and some but not all proxies can be curious but honest, compromised and colluding. Cost analysis has been conducted to quantify the extra overhead incurred by the MU-ORAM design
    • …
    corecore