9 research outputs found

    Prevalence of palate-gingival groove in patients of Dhulikhel Hospital

    No full text
    Background: Palato-gingival groove is a rare developmental anomaly leading to pulpal and periodontal diseases. Radicular extensions of these grooves are areas for plaque accumulation which are difficult to clean. Its clinical and radiographic findings mimic endo-perio lesions leading to diagnostic dilemma, ineffective treatment attempts and treatment failures. Objectives: To investigate the prevalence of coronal and radicular palato-gingival groove in dental patients visiting Dhulikhel Hospital and its association with gingival disease. Methods: Patients (N=231) visiting dental out-patient department of Dhulikhel Hospital, were examined for the presence or absence of palato-gingival groove in maxillary anteriors. Loe and Silness Gingival index was also recorded for all the patients using University of North Caroline-15 periodontal probe. Chisquare test was used to test the association of the presence of palato-gingival groove and gingival disease. P value of &lt;0.05 was considered to be significant. Results: A total of 1362 maxillary anterior teeth were included in the study. The prevalence of coronal palatogingival groove among 1362 teeth was 6.6%. Coronal palato-gingival grooves were more common in females (56.6%) than in male (43.3%) patients. Prevalence of radicular groove was only 0.88% for lateral incisors and 0.2% for canines. There was no significant association between palate-gingival groove and gingival disease (P=0.91). Conclusion: The prevalence of palato-gingival groove is common in dental patients visiting Dhulikhel Hospital. Gingival disease is not significantly associated with palate-gingival groove. DOI: http://dx.doi.org/10.3126/jcmsn.v10i1.12765 Journal of College of Medical Sciences-Nepal, 2014, Vol.10(1); 32-36</p

    Double planar Wire Arrays at enhanced Current on Zebra

    No full text
    International audienceDouble Planar Wire Arrays (DPWA), which consist of two parallel rows of wires, have demonstrated high radiation efficiency (up to 30 kJ), compact size (1.5-3 mm), and pulse shaping capabilities in experiments at 1 MA Zebra. DPWAs are also very suitable for the new compact multi-source hohlraum concept. It was shown that their implosion dynamics strongly depends on the critical load parameter, the aspect ratio (width to inter-planar gap &#916;). Recently, we studied larger sized DPWAs at the increased current of 1.5-1.7 MA that provided enhanced energy coupling in plasma and better diagnostic access to observable plasma regions. The new regimes of implosions with asymmetric jets, no precursor formation and very early radiation for larger sized DPWAs (&#916;=9 mm) with low aspect ratio of 0.54 were demonstrated. As a development of this work, new experiments at the enhanced current with the DPWAs from Alumel (mostly Ni) with &#916;=6 mm and higher aspect ratio were performed. The different implosion and radiative signatures were observed that are presented and analyzed such as formation of the precursor in the middle of the array, no foot pulse emission but a very broad XRD signal, and L-shell radiation before the XRD peak but not so early as for larger PWAs. Also, simultaneously with soft x-ray L-shell Ni radiation, hard x-ray K-shell Ni radiation was recorded in a broad range from 13 ns before up to 18 ns after the XRD peak showing the temporal evolution of characteristic cold Ni K&#945; emission as well as some adjacent spectral features from hotter plasmas. Non-LTE modeling of such K-shell features provided time history of ionization balance of Ni ions and is compared with results of L-shell modeling

    Mixed double planar wire arrays on Michigan's Ltd generator

    No full text
    International audienceDouble Planar Wire Arrays (DPWA), which consist of two parallel rows of wires, have previously demonstrated high radiation efficiency, compact size, and usefulness for various applications in experiments on a University-scale high-impedance Z-pinch generator1. Recently, we successfully performed two experimental campaigns with PWAs on the University of Michigan's low-impedance MAIZE (Linear Transformer Driver (LTD)-driven generator, 0.1ohm, 0.5-1 MA, 100-180 ns) in collaboration with the UM team. The details and the analysis of the results of the first experimental campaign can be found in Ref. [2]. The second experimental campaign was focused on studying the implosion and radiative characteristics of DPWAs using a diagnostic set similar to the first campaign, including: filtered X-ray diodes, X-ray spectrographs and pinhole cameras, and a new four-frame shadowgraphy system with 2-ns, 532 nm frequency doubled Nd:YAG laser. Here we present the results of four, mixed-DPWA shots with the load consisting of one plane with 6 Al wires of 10¿¿m diameter and another plane of 6 stainless steel wires of 5.1 ¿¿m diameter. The rise-time of the current varies between 175 and 225 ns and shadowgraphy images cover the broad span of time from as early as 116 ns to as late as 304 ns. The shadowgraphy images show ablating and imploding mixed DPWAs that are very different from the images of uniform DPWAs. There is a clearly observed asymmetry of implosions of two wire array planes dependent on the material of each plane, (early time images in particular), captured also by X-ray pinhole images. WADM is used for the analysis of shadowgraphy images. X-ray spectra display both K-shell Al and L-shell Fe features analyzed with non-LTE modeling. Advantages of using mixed wire arrays are discussed. [1] V. L. Kantsyrev et al, Phys. Plasmas 15, 030704 (2008). [2] A.S. Safronova, V.L. Kantsyrev, M.E. Weller, V.V. Shlyaptseva, I.K. Shrestha, M. Lorance, M. Schmidt-Petersen, A. Stafford. M. Cooper, A.M. Steiner, D.A. Yager-Elorriaga, S.G. Patel, N.M. Jordan, R.M. Gilgenbach, A.S. Chuvatin, IEEE TPS, Special Issue on Plenary and Invited papers from ICOPS 2015, to be published, April 2016. * This work was supported by NNSA under DOE Cooperative Agreement DE-NA0001984

    Appendicitis risk prediction models in children presenting with right iliac fossa pain (RIFT study): a prospective, multicentre validation study.

    No full text
    Background Acute appendicitis is the most common surgical emergency in children. Differentiation of acute appendicitis from conditions that do not require operative management can be challenging in children. This study aimed to identify the optimum risk prediction model to stratify acute appendicitis risk in children. Methods We did a rapid review to identify acute appendicitis risk prediction models. A prospective, multicentre cohort study was then done to evaluate performance of these models. Children (aged 5\u201315 years) presenting with acute right iliac fossa pain in the UK and Ireland were included. For each model, score cutoff thresholds were systematically varied to identify the best achievable specificity while maintaining a failure rate (ie, proportion of patients identified as low risk who had acute appendicitis) less than 5%. The normal appendicectomy rate was the proportion of resected appendixes found to be normal on histopathological examination. Findings 15 risk prediction models were identified that could be assessed. The cohort study enrolled 1827 children from 139 centres, of whom 630 (34\ub75%) underwent appendicectomy. The normal appendicectomy rate was 15\ub79% (100 of 630 patients). The Shera score was the best performing model, with an area under the curve of 0\ub784 (95% CI 0\ub782\u20130\ub786). Applying score cutoffs of 3 points or lower for children aged 5\u201310 years and girls aged 11\u201315 years, and 2 points or lower for boys aged 11\u201315 years, the failure rate was 3\ub73% (95% CI 2\ub70\u20135\ub72; 18 of 539 patients), specificity was 44\ub73% (95% CI 41\ub74\u201347\ub72; 521 of 1176), and positive predictive value was 41\ub74% (38\ub75\u201344\ub74; 463 of 1118). Positive predictive value for the Shera score with a cutoff of 6 points or lower (72\ub76%, 67\ub74\u201377\ub74) was similar to that of ultrasound scan (75\ub70%, 65\ub73\u201383\ub71). Interpretation The Shera score has the potential to identify a large group of children at low risk of acute appendicitis who could be considered for early discharge. Risk scoring does not identify children who should proceed directly to surgery. Medium-risk and high-risk children should undergo routine preoperative ultrasound imaging by operators trained to assess for acute appendicitis, and MRI or low-dose CT if uncertainty remains. Funding None
    corecore