357 research outputs found

    TRMM radar

    Get PDF
    The results of a conceptual design study and the performance of key components of the Bread Board Model (BBM) of the Tropical Rainfall Measuring Mission (TRMM) radar are presented. The radar, which operates at 13.8 GHz and is designed to meet TRMM mission objectives, has a minimum measurable rain rate of 0.5 mm/h with a range resolution of 250 m, a horizontal resolution of about 4 km, and a swath width of 220 km. A 128-element active phased array system is adopted to achieve contiguous scanning within the swath. The basic characteristics of BBM were confirmed by experiments. The development of EM started with the cooperation of NASDA and CRL

    Malignant schwannoma of the upper mediastinum originating from the vagus nerve

    Get PDF
    BACKGROUND: Malignant schwannoma of the upper mediastinum originating from the vagus nerve is extremely rare. CASE PRESENTATION: A 46-year-old female was admitted for a left cervical mass which was associated with both hoarseness and Horner's syndrome. Chest computed tomography showed a mass extending from the left upper mediastinum to the left supraclavicular area. A fine needle aspiration cytological examination suggested primary lung cancer stage IIIB large cell carcinoma. After administering induction chemo-radiotherapy, a complete surgical resection was performed. The tumor was found to involve both the left vagus nerve and the left sympathetic nerve. Histological examination of the resected specimen revealed the tumor to be malignant schwannoma. CONCLUSION: Despite incorrect preoperative diagnosis, the multimodality treatment administered in this case, including induction chemo-radiotherapy and surgery, proved to be effective

    Cyclin T1 stabilizes expression levels of HIV-1 Tat in cells

    Full text link
    Transcription from HIV-1 proviral DNA is a rate-determining step for HIV-1 replication. Interaction between the cyclin T1 (CycT1) subunit of positive transcription elongation factor b (P-TEFb) and the Tat transactivator protein of HIV-1 is crucial for viral transcription. CycT1 also interacts directly with the transactivation-responsive element (TAR) located on the 5′end of viral mRNA, as well as with Tat through the Tat–TAR recognition motif (TRM). These molecular interactions represent a critical step for stimulation of HIV transcription. Thus, Tat and CycT1 are considered to be feasible targets for the development of novel anti-HIV therapies. In this study, we demonstrate that CycT1 is positively involved in the Tat protein stability. Selective degradation of CycT1 by small interfering RNA (siRNA) culminated in proteasome-mediated degradation of Tat and eventual inhibition of HIV-1 gene expression. We noted that the siRNA-mediated knockdown of CycT1 could inhibit HIV-1 transcription without affecting cell viability and Tat mRNA levels. These findings clearly indicate that CycT1 is a feasible therapeutic target, and inactivation or depletion of CycT1 should effectively inhibit HIV replication by destabilizing Tat and suppressing Tat-mediated HIV transcription.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78606/1/j.1742-4658.2009.07424.x.pd
    corecore