Cascade Sequence of Photooxygenation-Epoxidation for the Flow Synthesis of Epoxy Alcohols.

A photooxygenation-epoxidation cascade sequence converting alkenes to epoxy alcohols was developed and evaluated in batch and continuous-flow systems. In the batch system, the undesired interactions between the photooxygenation and epoxidation catalysts resulted in suboptimal yields, whereas the fine control of reaction parameters in the flow system allowed the allyl hydroperoxides produced through photooxygenation of alkenes to be rapidly converted to epoxy alcohols in yields of up to 93%. The developed procedure allows one to avoid an important synthetic bottleneck, works well where traditional batch synthesis fails, and can be scaled up to meet the needs of industrial production, thus presenting a valuable addition to the toolbox of practicing organic chemists.

On the Deployment and Noise Filtering of Vehicular Radar Application for Detection Enhancement in Roads and Tunnels.

Recently, radar technology has attracted attention for the realization of an intelligent transportation system (ITS) to monitor, track, and manage vehicle traffic on the roads as well as adaptive cruise control (ACC) and automatic emergency braking (AEB) for driving assistance of vehicles. However, when radar is installed on roads or in tunnels, the detection performance is significantly dependent on the deployment conditions and environment around the radar. In particular, in the case of tunnels, the detection accuracy for a moving vehicle drops sharply owing to the diffuse reflection of radio frequency (RF) signals. In this paper, we propose an optimal deployment condition based on height and tilt angle as well as a noise-filtering scheme for RF signals so that the performance of vehicle detection can be robust against external conditions on roads and in tunnels. To this end, first, we gather and analyze the misrecognition patterns of the radar by tracking a number of randomly selected vehicles on real roads. In order to overcome the limitations, we implement a novel road watch module (RWM) that is easily integrated into a conventional radar system such as Delphi ESR. The proposed system is able to perform real-time distributed data processing of the target vehicles by providing independent queues for each object of information that is incoming from the radar RF. Based on experiments with real roads and tunnels, the proposed scheme shows better performance than the conventional method with respect to the detection accuracy and delay time. The implemented system also provides a user-friendly interface to monitor and manage all traffic on roads and in tunnels. This will accelerate the popularization of future ITS services.

Hysteroscopic endometrial ablation as a treatment for abnormal uterine bleeding in patients with renal transplants.

STUDY OBJECTIVE: To assess the effectiveness and safety of hysteroscopic endometrial ablation as a surgical management of abnormal uterine bleeding that develops in patients with renal transplants. DESIGN: Retrospective study (Canadian Task Force classification II-2). SETTING: Yonsei University Medical College, Severance Hospital. PATIENTS: Sixty-two women with abnormal uterine bleeding who had undergone renal transplantation. INTERVENTION: Hysteroscopic endometrial ablation. MEASUREMENTS AND MAIN RESULTS: Fifty-four out of 62 patients (87.0%) who had undergone hysteroscopic endometrial ablation reported decreased bleeding (95% CI: 0.76 to 0.94): amenorrhea in 25 (40.3%), spotting in 19 (30.6%), and eumenorrhea in 10 (16.1%). Mean follow-up duration was 6 months. No complications related to the procedure were reported. Levonorgestrel-releasing intrauterine systems (LNG-IUSs) were inserted into eight patients who experienced continuous bleeding, five of whom showed symptomatic improvement: spotting in three (4.9%) and eumenorrhea in two (3.2%). The three patients (4.9%) in whom the LNG-IUS had no effect had hysterectomies, and the resultant pathologic findings were two cases of adenomyosis and one case of simple endometrial hyperplasia without atypia. CONCLUSION: Hysteroscopic endometrial ablation as a surgical management of abnormal uterine bleeding that develops in patients with renal transplants is an effective and safe procedure.

Endometriosis in an adolescent population: the severance hospital in Korean experience.

The records of adolescent patients (10-21), who were admitted to the severance hospital between 1990 and 1999, were reviewed retrospectively to evaluate the age distribution, diagnosis, clinical stage, and treatment for endometriosis in adolescents. Thirty-nine patients who had undergone a laparotomy or laparoscopy and were diagnosed with endometriosis were identified. Endometriosis was classified according to the revised American Fertility Society classification (AFS). The chief symptoms leading to the diagnosis, clinical stage, age distribution, and treatment modality were reviewed. All patients, whose average age of menarche was 14.2, were diagnosed with endometriosis with an average interval of 5.9 years after menarche. The chief symptoms leading to the diagnosis were chronic pelvic pain (27%), acute pelvic pain (21%), a palpable pelvic mass (21%), and dysmenorrhea (18%). A laparoscopy was performed in 20 (51%). The majority of patients (44%) presented with the revised AFS classification stage II. Four patients (10%) presented with stage I, 11 (28%) with stage III and 7 (18%) with stage IV. Management after surgery included GnRH agonists (64.1%), expectant managements (25.7%), OCPs (5.1%) and danazol (5.1%). In adolescents with chronic pelvic pain, endometriosis is not rare. Therefore, early referral to a gynecologist to diagnose the etiology of the pelvic pain and initiate appropriate therapy is recommended.

Effect of hysterectomy on conserved ovarian function.

The aim of this study was to assess the impact of premenopausal Total Abdominal Hysterectomy (TAH) on the function of the remaining ovaries by reviewing the menopausal age in TAH treated patients. We retrospectively reviewed the medical records of 510 women who had previously undergone TAH, either with or without unilateral salpingo-oophorectomy, due to benign disease at the department of Obstetrics and Gynecology, Yonsei University College of Medicine, between Jan 1989 and Dec 1992. Out of the 510 women, the 94 who were throughly followed up were included in the study, and their menopausal age based on patient symptoms was compared to that of the control group. The mean menopausal age in TAH treated patients was significantly lower than that of the control group (P < 0.001). There was a positive correlation between age at operation and menopausal age. From this study, we could conclude that TAH accelerated ovarian dysfunction, and that the younger the patient was at the time of operation, the earlier the onset of menopause. It is hence apparent that women treated with TAH are at risk of early menopause and should receive adequate hormone replacement therapy.