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Sample records for curve angiographic analysis

  1. Endovascular image-guided treatment of in-vivo model aneurysms with asymmetric vascular stents (AVS): evaluation with time-density curve angiographic analysis and histology.

    Dohatcu, A; Ionita, C N; Paciorek, A; Bednarek, D R; Hoffmann, K R; Rudin, S

    2008-01-01

    In this study, we compare the results obtained from Time-Density Curve (TDC) analysis of angiographic imaging sequences with histological evaluation for a rabbit aneurysm model treated with standard stents and new asymmetric vascular stents (AVS) placed by image-guided endovascular deployment. AVSs are stents having a low-porosity patch region designed to cover the aneurysm neck and occlude blood flow inside. To evaluate the AVSs, rabbits with elastase-induced aneurysm models (n=20) were divided into three groups: the first (n=10) was treated with an AVS, the second (n=5) with a non-patch standard coronary stent, and third was untreated as a control (n=5). We used TDC analysis to measure how much contrast media entered the aneurysm before and after treatment. TDCs track contrast-media-density changes as a function of time over the region of interest in x-ray DSA cine-sequences. After 28 days, the animals were sacrificed and the explanted specimens were histologically evaluated. The first group showed an average reduction of contrast flow into the aneurysm of 95% after treatment with an AVS with fully developed thrombus at 28 days follow-up. The rabbits treated with standard stents showed an increase in TDC residency time after treatment and partial-thrombogenesis. The untreated control aneurysms displayed no reduction in flow and were still patent at follow-up. The quantitative TDC analysis findings were confirmed by histological evaluation suggesting that the new AVS has great potential as a definitive treatment for cerebro-vascular aneurysms and that angiographic TDC analysis can provide in-vivo verification.

  2. ROBUST DECLINE CURVE ANALYSIS

    Sutawanir Darwis

    2012-05-01

    Full Text Available Empirical decline curve analysis of oil production data gives reasonable answer in hyperbolic type curves situations; however the methodology has limitations in fitting real historical production data in present of unusual observations due to the effect of the treatment to the well in order to increase production capacity. The development ofrobust least squares offers new possibilities in better fitting production data using declinecurve analysis by down weighting the unusual observations. This paper proposes a robustleast squares fitting lmRobMM approach to estimate the decline rate of daily production data and compares the results with reservoir simulation results. For case study, we usethe oil production data at TBA Field West Java. The results demonstrated that theapproach is suitable for decline curve fitting and offers a new insight in decline curve analysis in the present of unusual observations.

  3. Shock Index Correlates with Extravasation on Angiographs of Gastrointestinal Hemorrhage: A Logistics Regression Analysis

    Nakasone, Yutaka; Ikeda, Osamu; Yamashita, Yasuyuki; Kudoh, Kouichi; Shigematsu, Yoshinori; Harada, Kazunori

    2007-01-01

    We applied multivariate analysis to the clinical findings in patients with acute gastrointestinal (GI) hemorrhage and compared the relationship between these findings and angiographic evidence of extravasation. Our study population consisted of 46 patients with acute GI bleeding. They were divided into two groups. In group 1 we retrospectively analyzed 41 angiograms obtained in 29 patients (age range, 25-91 years; average, 71 years). Their clinical findings including the shock index (SI), diastolic blood pressure, hemoglobin, platelet counts, and age, which were quantitatively analyzed. In group 2, consisting of 17 patients (age range, 21-78 years; average, 60 years), we prospectively applied statistical analysis by a logistics regression model to their clinical findings and then assessed 21 angiograms obtained in these patients to determine whether our model was useful for predicting the presence of angiographic evidence of extravasation. On 18 of 41 (43.9%) angiograms in group 1 there was evidence of extravasation; in 3 patients it was demonstrated only by selective angiography. Factors significantly associated with angiographic visualization of extravasation were the SI and patient age. For differentiation between cases with and cases without angiographic evidence of extravasation, the maximum cutoff point was between 0.51 and 0.0.53. Of the 21 angiograms obtained in group 2, 13 (61.9%) showed evidence of extravasation; in 1 patient it was demonstrated only on selective angiograms. We found that in 90% of the cases, the prospective application of our model correctly predicted the angiographically confirmed presence or absence of extravasation. We conclude that in patients with GI hemorrhage, angiographic visualization of extravasation is associated with the pre-embolization SI. Patients with a high SI value should undergo study to facilitate optimal treatment planning

  4. Clinical and angiographic characteristics of patients likely to have vulnerable plaques: analysis from the PROSPECT study.

    Bourantas, Christos V; Garcia-Garcia, Hector M; Farooq, Vasim; Maehara, Akiko; Xu, Ke; Généreux, Philippe; Diletti, Roberto; Muramatsu, Takashi; Fahy, Martin; Weisz, Giora; Stone, Gregg W; Serruys, Patrick W

    2013-12-01

    This study sought to determine the clinical and angiographic variables that would identify patients with high-risk "vulnerable" coronary plaques. In the PROSPECT (Providing Regional Observations to Study Predictors of Events in the Coronary Tree) study, in patients successfully treated for acute coronary syndrome (ACS), plaque composition, plaque burden, and minimal luminal area as detected by 3-vessel radiofrequency intravascular ultrasound (IVUS) imaging were associated with an increased risk of developing future events from untreated atherosclerotic lesions (vulnerable plaques). Whether baseline demographic and angiographic findings can be used to identify patients most likely to have vulnerable coronary plaques has not been examined. On the basis of 3-vessel radiofrequency IVUS imaging, patents in the PROSPECT trial were classified in 2 groups according to whether or not one or more untreated high-risk plaques were present, defined as having ≥2 high-risk features (a thin-cap fibroatheroma, plaque burden ≥70%, and/or minimal luminal area ≤4 mm(2)). The high-risk group (those with one or more high-risk lesions) had higher Framingham risk score (7.5 ± 3.4 vs. 6.9 ± 3.3; p = 0.04), more extensive coronary artery disease, and more nonculprit lesion-related cardiovascular events during the 3-year follow-up (hazard ratio: 2.63; 95% confidence interval: 1.62 to 3.66; p < 0.0001). However, demographic factors had poor discrimination in detecting high-risk patients (area under the curve 0.55), and discrimination was only slightly improved when angiographic variables were entered into the model (area under the curve 0.64). Clinical and angiographic characteristics had poor predictive accuracy in identifying patients with untreated high-risk plaques related to future adverse events. This finding highlights the potential value of comprehensive 3-vessel imaging assessment (either invasive or noninvasive) to evaluate plaque phenotype for more accurate risk

  5. Extended analysis of cooling curves

    Djurdjevic, M.B.; Kierkus, W.T.; Liliac, R.E.; Sokolowski, J.H.

    2002-01-01

    Thermal Analysis (TA) is the measurement of changes in a physical property of a material that is heated through a phase transformation temperature range. The temperature changes in the material are recorded as a function of the heating or cooling time in such a manner that allows for the detection of phase transformations. In order to increase accuracy, characteristic points on the cooling curve have been identified using the first derivative curve plotted versus time. In this paper, an alternative approach to the analysis of the cooling curve has been proposed. The first derivative curve has been plotted versus temperature and all characteristic points have been identified with the same accuracy achieved using the traditional method. The new cooling curve analysis also enables the Dendrite Coherency Point (DCP) to be detected using only one thermocouple. (author)

  6. Fully automatic algorithm for the analysis of vessels in the angiographic image of the eye fundus

    Koprowski Robert

    2012-06-01

    Full Text Available Abstract Background The available scientific literature contains descriptions of manual, semi-automated and automated methods for analysing angiographic images. The presented algorithms segment vessels calculating their tortuosity or number in a given area. We describe a statistical analysis of the inclination of the vessels in the fundus as related to their distance from the center of the optic disc. Methods The paper presents an automated method for analysing vessels which are found in angiographic images of the eye using a Matlab implemented algorithm. It performs filtration and convolution operations with suggested masks. The result is an image containing information on the location of vessels and their inclination angle in relation to the center of the optic disc. This is a new approach to the analysis of vessels whose usefulness has been confirmed in the diagnosis of hypertension. Results The proposed algorithm analyzed and processed the images of the eye fundus using a classifier in the form of decision trees. It enabled the proper classification of healthy patients and those with hypertension. The result is a very good separation of healthy subjects from the hypertensive ones: sensitivity - 83%, specificity - 100%, accuracy - 96%. This confirms a practical usefulness of the proposed method. Conclusions This paper presents an algorithm for the automatic analysis of morphological parameters of the fundus vessels. Such an analysis is performed during fluorescein angiography of the eye. The presented algorithm automatically calculates the global statistical features connected with both tortuosity of vessels and their total area or their number.

  7. Spontaneous regression of cerebral arteriovenous malformations: clinical and angiographic analysis with review of the literature

    Lee, S.K.; Vilela, P.; Willinsky, R.; TerBrugge, K.G.

    2002-01-01

    Spontaneous regression of cerebral arteriovenous malformation (AVM) is rare and poorly understood. We reviewed the clinical and angiographic findings in patients who had spontaneous regression of cerebral AVMs to determine whether common features were present. The clinical and angiographic findings of four cases from our series and 29 cases from the literature were retrospectively reviewed. The clinical and angiographic features analyzed were: age at diagnosis, initial presentation, venous drainage pattern, number of draining veins, location of the AVM, number of arterial feeders, clinical events during the interval period to thrombosis, and interval period to spontaneous thrombosis. Common clinical and angiographic features of spontaneous regression of cerebral AVMs are: intracranial hemorrhage as an initial presentation, small AVMs, and a single draining vein. Spontaneous regression of cerebral AVMs can not be predicted by clinical or angiographic features, therefore it should not be considered as an option in cerebral AVM management, despite its proven occurrence. (orig.)

  8. Intracranial infective aneurysms presenting with haemorrhage: An analysis of angiographic findings, management and outcome

    Venkatesh, Sudhakar K.; Phadke, Rajendra V.; Kalode, Ravi R.; Kumar, Sunil; Jain, Vijendra K.

    2000-01-01

    AIM: This study is an analysis of angiographic findings in 17 patients with infective aneurysms who presented with intracranial haemorrhage and reviews the management and outcome in the context of the existing literature. MATERIALS AND METHODS: A retrospective study of infective aneurysms in 17 patients was carried out. Cranial angiography was performed in all patients. The location, size and outline of aneurysms were analysed. Ten patients were managed conservatively and six patients underwent surgery for the ruptured infective aneurysms and were followed up for a period of 35.8 months and 23 months, respectively. RESULTS: Twenty-two aneurysms were identified (five unruptured) in 17 patients. Twenty aneurysms (90.9%) were distal in location and two (9.1%) proximal. Sixty percent were in the posterior circulation with 55% in the posterior cerebral artery (PCA) territory, 27.3% in the middle cerebral artery (MCA) territory and 9.1% in the anterior cerebral artery (ACA) territory. Fourteen aneurysms were small (3-5 mm) and eight were medium sized (6-9 mm). 72.7% of aneurysms had irregular outline and 27.3% regular outline. Out of the 10 ruptured aneurysms managed conservatively, eight resolved. One patient died, presumably due to rebleed, and one had infarction due to parent vessel thrombosis. Six aneurysms were surgically managed with good results. Of the five unruptured aneurysms one was surgically managed and the remaining four conservatively managed patients did not bleed during follow-up. CONCLUSION: Patients with ruptured infective aneurysms fared well with medical management and the outcome in this series is better than that reported in literature. Patients on conservative management, however, need closer monitoring with angiographic follow-up. Active management is required with enlarging or persisting aneurysms. Venkatesh, S.K. (2000)

  9. Comparative quantitative angiographic analysis of directional coronary atherectomy and balloon coronary angioplasty

    V.A.W.M. Umans (Victor); K.J. Beatt (Kevin); B.J.W.M. Rensing (Benno); W.R.M. Hermans (Walter); P.J. de Feyter (Pim); P.W.J.C. Serruys (Patrick)

    1991-01-01

    markdownabstract__Abstract__ An attempt to assess the “utility” of directional atherectomy was made using a new quantitative angiographic index. This index can be subdivided into an initial gain component and a restenosis component. The initial gain index is the ratio between the gain in diameter

  10. Coronary arterial Disease associated with arteriosclerosis in lower extremity: Angiographic analysis

    Kim, Ji Hye; Chung, Jin Wook; Lee, Seon Kyu; Han, Joon Koo; Park, Jae Hyung; Kim, Jae Seung; Han, Man Chung

    1993-01-01

    We performed both peripheral and coronary angiographies in 52 patients with an arteriosclerosis in lower extremities. The severity of arteriosclerotic narrowing of the coronary and peripheral arteries were compared on angiographies. An angiographic vascular score(AVS, 0-5) reflecting the number and the degree of stenosis in 12 lower extremity arteries and three major coronary arteries was assigned to each angiogram and the sun of scores in the lower extremity arteries was compared with the incidence of significant coronary artery disease (more than grade 3) and coronary score. Relation of incidence and severity of vascular stenosis and risk factors (diabetes metallitus, hypertension, smoking, and hypercholesterolemia) was also analyzed. Thirty-four of 52 patients (65%) had an angiographically significant coronary artery disease. Thirteen of these 34 patients (38%) had no clinical symptom and sign of the ischemic heart disease. There was no statistically significant difference in the incidence and severity of coronary artery disease between high (more than 30) and low AVS group in lower extremity (p>0.14). All patients had at least one risk factor and 49 of 52 patients (94%) had multiple risk factors. Coronary angiography was normal in there patients with only one risk factors, and angiographically significant coronary artery disease existed in nine of 16 cases (56.3%) with two risk factors. 13 of 17 case (76.5%) with three risk factors, and 12 of 16 cases (75.0%) with all four risk factors. There were no significant correlations between individual risk factors and incidence, severity of arteriosclerosis in coronary and lower extremity arteries. In conclusion, angiographic evaluation of the coronary artery disease in patients with lower extremity arteriosclerosis is necessary because of the high chance of coronary artery disease and difficulty in the prediction of coronary artery disease with a severity of the peripheral arteriosclerosis, presence of various risk

  11. Bronchial and non-bronchial systemic arteries: value of multidetector CT angiography in diagnosis and angiographic embolisation feasibility analysis

    Lin, Yuning; Chen, Ziqian; Yang, Xizhang; Zhong, Qun; Zhang, Hongwen; Yang, Li; Xu, Shangwen; Li, Hui

    2013-01-01

    The aim of this study is to evaluate the diagnostic performance of multidetector CT angiography (CTA) in depicting bronchial and non-bronchial systemic arteries in patients with haemoptysis and to assess whether this modality helps determine the feasibility of angiographic embolisation. Fifty-two patients with haemoptysis between January 2010 and July 2011 underwent both preoperative multidetector CTA and digital subtraction angiography (DSA) imaging. Diagnostic performance of CTA in depicting arteries causing haemoptysis was assessed on a per-patient and a per-artery basis. The feasibility of the endovascular treatment evaluated by CTA was analysed. Sensitivity, specificity, and positive and negative predictive values for those analyses were determined. Fifty patients were included in the artery-presence-number analysis. In the per-patient analysis, neither CTA (P=0.25) nor DSA (P=1.00) showed statistical difference in the detection of arteries causing haemoptysis. The sensitivity, specificity, and positive and negative predictive values were 94%, 100%, 100%, and 40%, respectively, for the presence of pathologic arteries evaluated by CTA, and 98%, 100%, 100%, and 67%, respectively, for DSA. On the per-artery basis, CTA correctly identified 97% (107/110). Fifty-two patients were included in the feasibility analysis. The performance of CTA in predicting the feasibility of angiographic embolisation was not statistically different from the treatment performed (P=1.00). The sensitivity, specificity, and positive and negative predictive values were 96%, 80%, 98% and 67%, respectively, for CTA. Multidetector CTA is an accurate imaging method in depicting the presence and number of arteries causing haemoptysis. This modality is also useful for determining the feasibility of angiographic embolisation for haemoptysis.

  12. Bronchial and non-bronchial systemic arteries: value of multidetector CT angiography in diagnosis and angiographic embolisation feasibility analysis.

    Lin, Yuning; Chen, Ziqian; Yang, Xizhang; Zhong, Qun; Zhang, Hongwen; Yang, Li; Xu, Shangwen; Li, Hui

    2013-12-01

    The aim of this study is to evaluate the diagnostic performance of multidetector CT angiography (CTA) in depicting bronchial and non-bronchial systemic arteries in patients with haemoptysis and to assess whether this modality helps determine the feasibility of angiographic embolisation. Fifty-two patients with haemoptysis between January 2010 and July 2011 underwent both preoperative multidetector CTA and digital subtraction angiography (DSA) imaging. Diagnostic performance of CTA in depicting arteries causing haemoptysis was assessed on a per-patient and a per-artery basis. The feasibility of the endovascular treatment evaluated by CTA was analysed. Sensitivity, specificity, and positive and negative predictive values for those analyses were determined. Fifty patients were included in the artery-presence-number analysis. In the per-patient analysis, neither CTA (P = 0.25) nor DSA (P = 1.00) showed statistical difference in the detection of arteries causing haemoptysis. The sensitivity, specificity, and positive and negative predictive values were 94%, 100%, 100%, and 40%, respectively, for the presence of pathologic arteries evaluated by CTA, and 98%, 100%, 100%, and 67%, respectively, for DSA. On the per-artery basis, CTA correctly identified 97% (107/110). Fifty-two patients were included in the feasibility analysis. The performance of CTA in predicting the feasibility of angiographic embolisation was not statistically different from the treatment performed (P = 1.00). The sensitivity, specificity, and positive and negative predictive values were 96%, 80%, 98% and 67%, respectively, for CTA. Multidetector CTA is an accurate imaging method in depicting the presence and number of arteries causing haemoptysis. This modality is also useful for determining the feasibility of angiographic embolisation for haemoptysis. © 2013 The Authors. Journal of Medical Imaging and Radiation Oncology © 2013 The Royal Australian and New Zealand College of Radiologists.

  13. Angiographic analysis of animal model aneurysms treated with novel polyurethane asymmetric vascular stent (P-AVS): feasibility study.

    Ionita, Ciprian N; Dohatcu, Andreea; Sinelnikov, Andrey; Sherman, Jason; Keleshis, Christos; Paciorek, Ann M; Hoffmann, K R; Bednarek, D R; Rudin, S

    2009-01-01

    Image-guided endovascular intervention (EIGI), using new flow modifying endovascular devices for intracranial aneurysm treatment is an active area of stroke research. The new polyurethane-asymmetric vascular stent (P-AVS), a vascular stent partially covered with a polyurethane-based patch, is used to cover the aneurysm neck, thus occluding flow into the aneurysm. This study involves angiographic imaging of partially covered aneurysm orifices. This particular situation could occur when the vascular geometry does not allow full aneurysm coverage. Four standard in-vivo rabbit-model aneurysms were investigated; two had stent patches placed over the distal region of the aneurysm orifice while the other two had stent patches placed over the proximal region of the aneurysm orifice. Angiographic analysis was used to evaluate aneurysm blood flow before and immediately after stenting and at four-week follow-up. The treatment results were also evaluated using histology on the aneurysm dome and electron microscopy on the aneurysm neck. Post-stenting angiographic flow analysis revealed aneurysmal flow reduction in all cases with faster flow in the distally-covered case and very slow flow and prolonged pooling for proximal-coverage. At follow-up, proximally-covered aneurysms showed full dome occlusion. The electron microscopy showed a remnant neck in both distally-placed stent cases but complete coverage in the proximally-placed stent cases. Thus, direct flow (impingement jet) removal from the aneurysm dome, as indicated by angiograms in the proximally-covered case, was sufficient to cause full aneurysm healing in four weeks; however, aneurysm healing was not complete for the distally-covered case. These results support further investigations into the treatment of aneurysms by flow-modification using partial aneurysm-orifice coverage.

  14. Agreement between clinical estimation and a new quantitative analysis by Photoshop software in fundus and angiographic image variables.

    Ramezani, Alireza; Ahmadieh, Hamid; Azarmina, Mohsen; Soheilian, Masoud; Dehghan, Mohammad H; Mohebbi, Mohammad R

    2009-12-01

    To evaluate the validity of a new method for the quantitative analysis of fundus or angiographic images using Photoshop 7.0 (Adobe, USA) software by comparing with clinical evaluation. Four hundred and eighteen fundus and angiographic images of diabetic patients were evaluated by three retina specialists and then by computing using Photoshop 7.0 software. Four variables were selected for comparison: amount of hard exudates (HE) on color pictures, amount of HE on red-free pictures, severity of leakage, and the size of the foveal avascular zone (FAZ). The coefficient of agreement (Kappa) between the two methods in the amount of HE on color and red-free photographs were 85% (0.69) and 79% (0.59), respectively. The agreement for severity of leakage was 72% (0.46). In the two methods for the evaluation of the FAZ size using the magic and lasso software tools, the agreement was 54% (0.09) and 89% (0.77), respectively. Agreement in the estimation of the FAZ size by the lasso magnetic tool was excellent and was almost as good in the quantification of HE on color and on red-free images. Considering the agreement of this new technique for the measurement of variables in fundus images using Photoshop software with the clinical evaluation, this method seems to have sufficient validity to be used for the quantitative analysis of HE, leakage, and FAZ size on the angiograms of diabetic patients.

  15. Quantitative assessment of angiogenesis in the chick embryo and its chorioallantoic membrane by computerised analysis of angiographic images

    Nikiforidis, G.; Papazafiropoulos, D.; Siablis, D.; Karnabatidis, D.; Hatjikondi, O.; Dimopoulos, J.

    1999-01-01

    We studied, in vivo, the angiogenesis process in the chick embryo and its chorioallantoic membrane (CAM) using digital subtraction angiography (DSA) in conjunction with computer-assisted image analysis. In a series of fertilised eggs, angiography was carried out at days 8, 10, 12 and 14 of embryonic development. The angiographic images were digitised and subsequently processed for a specific image analysis. A set of specific morphological parameters has been defined to allow an analytical characterisation of the vascularity status. Vessels were classified into three categories according to their diameter (50-100, 100-200, and >200 μm). The data were normalised and statistically evaluated. Graphs showing the development of angiogenesis were obtained. Total vascular area revealed a continuous rise, whereas, total vascular length increased until day 12 and then it started decreasing. These morphometric parameters in the first two vessel categories progressively increased throughout the entire period of development, whereas in the third category they increased until day 10 and then they started decreasing. By applying a vascular casting technique CAM vessels were visualised and compared with those extracted from the processed angiographic image. The comparison revealed that there is exact matching for the first two vessel categories (diameters higher than 100 μm) while the matching of the third category (diameters between 50 and 100 μm) is approximate

  16. Incorporating experience curves in appliance standards analysis

    Desroches, Louis-Benoit; Garbesi, Karina; Kantner, Colleen; Van Buskirk, Robert; Yang, Hung-Chia

    2013-01-01

    There exists considerable evidence that manufacturing costs and consumer prices of residential appliances have decreased in real terms over the last several decades. This phenomenon is generally attributable to manufacturing efficiency gained with cumulative experience producing a certain good, and is modeled by an empirical experience curve. The technical analyses conducted in support of U.S. energy conservation standards for residential appliances and commercial equipment have, until recently, assumed that manufacturing costs and retail prices remain constant during the projected 30-year analysis period. This assumption does not reflect real market price dynamics. Using price data from the Bureau of Labor Statistics, we present U.S. experience curves for room air conditioners, clothes dryers, central air conditioners, furnaces, and refrigerators and freezers. These experience curves were incorporated into recent energy conservation standards analyses for these products. Including experience curves increases the national consumer net present value of potential standard levels. In some cases a potential standard level exhibits a net benefit when considering experience, whereas without experience it exhibits a net cost. These results highlight the importance of modeling more representative market prices. - Highlights: ► Past appliance standards analyses have assumed constant equipment prices. ► There is considerable evidence of consistent real price declines. ► We incorporate experience curves for several large appliances into the analysis. ► The revised analyses demonstrate larger net present values of potential standards. ► The results imply that past standards analyses may have undervalued benefits.

  17. Numerical analysis of thermoluminescence glow curves

    Gomez Ros, J. M.; Delgado, A.

    1989-01-01

    This report presents a method for the numerical analysis of complex thermoluminescence glow curves resolving the individual glow peak components. The method employs first order kinetics analytical expressions and is based In a Marquart-Levenberg minimization procedure. A simplified version of this method for thermoluminescence dosimetry (TLD) is also described and specifically developed to operate whit Lithium Fluoride TLD-100. (Author). 36 refs

  18. Light Curve Analysis of SAO23229

    Ho-Il Kim

    1993-06-01

    Full Text Available We have made UBV light curves of a newly discovered eclipsing binary, SAO23229 at Sobaeksan Astronomy Observatory. We determined a minimum light time of HJD2448636.1170+/-0.0005 that is 3 minutes later than predicted time, and founda peculiar light variation at phase 0.75 that may not be secondary eclipse. Orbital period of SAO23229 would be 4.2 days rather than 2.1 days. Our analysis of the light curves shows that SAO23229 has a detached configuration consisting of two almost identical F type main sequence stars.

  19. Intractable Postpartum Bleeding: A Comparison of the Retrospective Analysis of Angiographic Findings and Transcatheter Arterial Embolization According to Delivery Pattern

    Ahn, Eun Jung; Kim, Young Hwan; Kim, Si Hyung; Choi, Jin Soo; Park, Jun Cheol; Kwon, Sang Hun; Jo, Chi Heum; Cha, Soon Do [Keimyung University College of Medicine, Daegu (Korea, Republic of)

    2008-12-15

    We evaluated the technical aspect and efficacy of transcatheter arterial embolization (TAE) in cases of intractable postpartum bleeding by comparing the angiographic findings women patients according to their delivery pattern. Between July of 2003 and March of 2008, 55 female patients were enrolled in this study. Of the 55 patients, 36 underwent a vaginal delivery (group 1), whereas 19 underwent a cesarean section delivery (group 2). We retrospectively evaluated the angiographic findings and the embolization technique between groups, using a Pearson Chi-Square test. Medical records and telephone interview findings were also reviewed to evaluate the efficacy of TAE and the outcome of fertility. Significantly greater positive angiographic findings were found in group 2 (63.2%) relative to group 1 (30.6%). For positive angiographic findings, except for AVM, the embolization was performed using coil or glue with gelfoam. For the negative angiographic findings or AVM, the gelfoam was the only embolic agent used. In all patients except for one, bleeding stopped after embolization. Major complications occurred in 2 patients only, and included uterine synechia and perforation. All patients except for one recovered after menstruation. In total, four patients became pregnant and one patient delivered a healthy infant. Positive angiographic findings requiring embolization with coil or glue, as well as gelfoam, were more commonly encountered in group 2 than in group 1. Based on the outcome of the study group, TAE is a safe and effective treatment for intractable postpartum bleeding and is also useful for preserving fertility.

  20. Intractable Postpartum Bleeding: A Comparison of the Retrospective Analysis of Angiographic Findings and Transcatheter Arterial Embolization According to Delivery Pattern

    Ahn, Eun Jung; Kim, Young Hwan; Kim, Si Hyung; Choi, Jin Soo; Park, Jun Cheol; Kwon, Sang Hun; Jo, Chi Heum; Cha, Soon Do

    2008-01-01

    We evaluated the technical aspect and efficacy of transcatheter arterial embolization (TAE) in cases of intractable postpartum bleeding by comparing the angiographic findings women patients according to their delivery pattern. Between July of 2003 and March of 2008, 55 female patients were enrolled in this study. Of the 55 patients, 36 underwent a vaginal delivery (group 1), whereas 19 underwent a cesarean section delivery (group 2). We retrospectively evaluated the angiographic findings and the embolization technique between groups, using a Pearson Chi-Square test. Medical records and telephone interview findings were also reviewed to evaluate the efficacy of TAE and the outcome of fertility. Significantly greater positive angiographic findings were found in group 2 (63.2%) relative to group 1 (30.6%). For positive angiographic findings, except for AVM, the embolization was performed using coil or glue with gelfoam. For the negative angiographic findings or AVM, the gelfoam was the only embolic agent used. In all patients except for one, bleeding stopped after embolization. Major complications occurred in 2 patients only, and included uterine synechia and perforation. All patients except for one recovered after menstruation. In total, four patients became pregnant and one patient delivered a healthy infant. Positive angiographic findings requiring embolization with coil or glue, as well as gelfoam, were more commonly encountered in group 2 than in group 1. Based on the outcome of the study group, TAE is a safe and effective treatment for intractable postpartum bleeding and is also useful for preserving fertility

  1. Incorporating Experience Curves in Appliance Standards Analysis

    Garbesi, Karina; Chan, Peter; Greenblatt, Jeffery; Kantner, Colleen; Lekov, Alex; Meyers, Stephen; Rosenquist, Gregory; Buskirk, Robert Van; Yang, Hung-Chia; Desroches, Louis-Benoit

    2011-10-31

    The technical analyses in support of U.S. energy conservation standards for residential appliances and commercial equipment have typically assumed that manufacturing costs and retail prices remain constant during the projected 30-year analysis period. There is, however, considerable evidence that this assumption does not reflect real market prices. Costs and prices generally fall in relation to cumulative production, a phenomenon known as experience and modeled by a fairly robust empirical experience curve. Using price data from the Bureau of Labor Statistics, and shipment data obtained as part of the standards analysis process, we present U.S. experience curves for room air conditioners, clothes dryers, central air conditioners, furnaces, and refrigerators and freezers. These allow us to develop more representative appliance price projections than the assumption-based approach of constant prices. These experience curves were incorporated into recent energy conservation standards for these products. The impact on the national modeling can be significant, often increasing the net present value of potential standard levels in the analysis. In some cases a previously cost-negative potential standard level demonstrates a benefit when incorporating experience. These results imply that past energy conservation standards analyses may have undervalued the economic benefits of potential standard levels.

  2. Analysis of characteristic performance curves in radiodiagnosis by an observer

    Kossovoj, A.L.

    1988-01-01

    Methods and ways of construction of performance characteristic curves (PX-curves) in roentgenology, their qualitative and quantitative estimation are described. Estimation of PX curves application for analysis of scintigraphic and sonographic images is presented

  3. Analysis of threshold curves for superconducting interferometers

    Peterson, R.L.; Hamilton, C.A.

    1979-01-01

    Threshold curves for multijunction superconducting interferometers have been calculated previously, showing general agreement with observed features, especially in symmetric cases. We here add some more details to the analysis, paying particular attention to the effects of asymmetries in coupling, inductance, or critical currents. Feed-loop inductance and flux quantization in the feed loop can be important. A changing lobe pattern over many periods, asymmetries within a period, shifting patterns between runs spanning a warm-up, and sudden changes in pattern because of noise in the environment are all quantitatively explainable on the basis of this model. By use of a single ''calibration curve'', the inductance for symmetric two- or three-junction interferometers can be obtained immediately

  4. Multislice computed tomography: angiographic emulation versus standard assessment for detection of coronary stenoses

    Schnapauff, Dirk; Hamm, Bernd; Dewey, Marc [Humboldt-Universitaet zu Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, P.O. Box 10098, Berlin (Germany); Duebel, Hans-Peter; Baumann, Gert [Charite - Universitaetsmedizin Berlin, Department of Cardiology, Berlin (Germany); Scholze, Juergen [Charite - Universitaetsmedizin Berlin, Charite Outpatient Centre, Berlin (Germany)

    2007-07-15

    The present study investigated angiographic emulation of multislice computed tomography (MSCT) (catheter-like visualization) as an alternative approach of analyzing and visualizing findings in comparison with standard assessment. Thirty patients (120 coronary arteries) were randomly selected from 90 prospectively investigated patients with suspected coronary artery disease who underwent MSCT (16-slice scanner, 0.5 mm collimation, 400 ms rotation time) prior to conventional coronary angiography for comparison of both approaches. Sensitivity and specificity of angiographic emulation [81% (26/32) and 93% (82/88)] were not significantly different from those of standard assessment [88% (28/32) and 99% (87/88)], while the per-case analysis time was significantly shorter for angiographic emulation than for standard assessment (3.4 {+-} 1.5 vs 7.0 {+-} 2.5 min, P < 0.001). Both interventional and referring cardiologists preferred angiographic emulation over standard curved multiplanar reformations of MSCT coronary angiography for illustration, mainly because of improved overall lucidity and depiction of sidebranches (P < 0.001). In conclusion, angiographic emulation of MSCT reduces analysis time, yields a diagnostic accuracy comparable to that of standard assessment, and is preferred by cardiologists for visualization of results. (orig.)

  5. Long-term Luminal Renarrowing After Successful Elective Coronary Angioplasty of Total Occlusions : A Quantitative Angiographic Analysis

    A.G. Violaris (Andonis); R. Melkert (Rein); P.W.J.C. Serruys (Patrick)

    1995-01-01

    textabstractBackground The long-term angiographic outcome after successful dilatation of coronary occlusions remains unclear. The objective of this study was to examine long-term restenosis after successful balloon dilatation of coronary occlusions at a predetermined time interval with quantitative

  6. Analysis of angiographic findings in arteriovenous malformations(AVM) of brain according to presenting clinical manifestations

    Kim, Jun Hyoung; Kim, Jae Kyun; Suh, Dae Chul and others

    1998-01-01

    To evaluate the different angio-architectures of brain arteriovenous malformations(AVMs) according to the presence of non-hemorrhagic symptoms or intracerebral (ICH) and/or intraventricular hemorrhage (IVH). The results of complete cerebral angiography obtained in 215 patients with AVM between 1989 and 1994 were retrospectively reviewed. The M:F ratio was 136:78 and their mean age was 29 (ranged 4-66) years. On the base of clinical presentation, CT and/or MR images, they were divided into hemorrhagic and non-hemorrhagic groups. Angiograms were analyzed by two radiologists for the size and location of nidus;the number of feeding arteries and the extent of aneurysm, stenosis, dural supply, and angiomatous change;the number of draining veins and the extent of deep or superficial drainage, stenosis, ectasia, kinking, and stasis. The standard chi-square test was used for statistical analysis. Hemorrhage was noted in 140 patients (65%), and no hemorrhage in 75 (35%). Hemorrhage was more common in AVM with deep-seated and callosal locations, a nidus of less than 2cm, single feeder and single venous drainage, and deep venous drainage only (p<0.05-0.001). Non-hemorrhagic presentations were more common in AVM with cortical and subcortical location, a nidus of more than 5cm, angiomatous change, dural supply, both superficial and deep venous drainage, kinking, and stasis(p<0.05-0.001). The angio-architechture of AVM with hemorrhage correlated with clinical symptomatic presentation. Analysis of the patterns of angioarchitectures useful for prognosis and in deciding the direction of treatment. =20

  7. Analysis of angiographic findings in cerebral arteriovenous malformation with hemorrhage: comparison between intracerebral and intraventricular hemorrhage

    Kim, Jae Kyun; Kim, Joon Hyung; Kwon, Jin Sook; Yoon, Soo Woong; Lee, Ho Kyu; Choi, Choong Gon; Suh, Dae Chul

    1998-01-01

    The purpose of this study was to analyze the angioarchitectures of cerebral arteriovenous malformation (AVM) and to determine whether there was correlation between angioarchitectures and patterns of intracranial hemorrhage (intracerebral, intraventricular, and both) in cerebral AVM. One hundred and twenty-eight patients who between November 1989 and December 1994 suffered supratentorial AVM with intracranial hemorrhage were studied retrospectively. Among 128 patients, intracerebral and intraventricular hemorrhage were seen in 68(53%) and 24 patients(19%), respectively, while both types were seen in the remaining 36 (28%). We analyzed the angioarchitectual characteristics of AVM, namely nidi, feeding arteries and draining veins, in three hemorrhagic groups of patients with intracerebral hemorrhage, intraventricular hemorrhage and both. The X 2 test or Fisher's exact test was used for statistical analysis. A cortically located nidus was most common in patients with intracerebral hemorrhage, while a periventricular location was most common in those with intraventricular hemorrhage (p<0.001). Location in the corpus callosum, choroid plexus, or intraventricular area was more frequent in the intraventricular than the intracerebral hemorrhagic group (p<0.05). Superficial venous drainage was most common in patients with intracerebral hemorrhage (p<0.001), and deep venous drainage in those with intraventricular hemorrhage (p=3D0.001). The angioarchitectual characteristics of cerebral arteriovenous malformation correlate significantly with patterns of intracranial hemorrhage, and awareness of the type of hemorrhage could help to manage patients and determine prognosis.=20

  8. Prospects for PV: a learning curve analysis

    Zwaan, Bob van der; Rabi, A.

    2003-01-01

    This article gives an overview of the current state-of-the-art of photovoltaic electricity technology, and addresses its potential for cost reductions over the first few decades of the 21st century. Current PV production cost ranges are presented, both in terms of capacity installation and electricity generation, of single crystalline silicon, multi-crystalline silicon, amorphous silicon and other thin film technologies. Possible decreases of these costs are assessed, as expected according to the learning-curve methodology. We also estimate how much PV could gain if external costs (due to environmental and health damage) of energy were internalised, for example by an energy tax. Our conclusions are that, (1) mainly due its high costs, PV electricity is unlikely to play a major role in global energy supply and carbon emissions abatement before 2020, (2) extrapolating learning curves observed in the past, one can expect its costs to decrease significantly over the coming years, so that a considerable PV electricity share world-wide could materialise after 2020, (3) niche-market applications, e.g. using stand-alone systems in remote areas, are crucial for continuing 'the ride along the learning curve', (4) damage costs of conventional (fossil) power sources are considerable, and their internalisation would improve the competitiveness of PV, although probably not enough to close the current cost gap. (author)

  9. Comparison of wind turbines based on power curve analysis

    NONE

    1998-02-01

    In the study measured power curves for 46 wind turbines were analyzed with the purpose to establish the basis for a consistent comparison of the efficiency of the wind turbines. Emphasis is on wind turbines above 500 kW rated power, with power curves measured after 1994 according to international recommendations. The available power curves fulfilling these requirements were smoothened according to a procedure developed for the purpose in such a way that the smoothened power curves are equally representative as the measured curves. The resulting smoothened power curves are presented in a standardized format for the subsequent processing. Using wind turbine data from the power curve documentation the analysis results in curves for specific energy production (kWh/M{sup 2}/yr) versus specific rotor load (kW/M{sup 2}) for a range of mean wind speeds. On this basis generalized curves for specific annual energy production versus specific rotor load are established for a number of generalized wind turbine concepts. The 46 smoothened standardized power curves presented in the report, the procedure developed to establish them, and the results of the analysis based on them aim at providers of measured power curves as well as users of them including manufacturers, advisors and decision makers. (au)

  10. Prevalence, Risk Factors, and Outcome of Myocardial Infarction with Angiographically Normal and Near-Normal Coronary Arteries: A Systematic Review and Meta-Analysis

    Samad Ghaffari

    2016-12-01

    Full Text Available Context: Coronary artery diseases are mostly detected using angiographic methods demonstrating arteries status. Nevertheless, Myocardial Infarction (MI may occur in the presence of angiographically normal coronary arteries. Therefore, this study aimed to investigate the prevalence of MI with normal angiography and its possible etiologies in a systematic review. Evidence Acquisition: In this meta-analysis, the required data were collected from PubMed, Science Direct, Google Scholar, Scopus, Magiran, Scientific Information Database, and Medlib databases using the following keywords: “coronary angiograph”, “normal coronary arteries”, “near-normal coronary arteries”, “heart diseases”, “coronary artery disease”, “coronary disease”, “cardiac troponin I”, “Myocardial infarction”, “risk factor”, “prevalence”, “outcome”, and their Persian equivalents. Then, Comprehensive Meta-Analysis software, version 2 using randomized model was employed to determine the prevalence of each complication and perform the meta-analysis. P values less than 0.05 were considered to be statistically significant. Results: Totally, 20 studies including 139957 patients were entered into the analysis. The patients’ mean age was 47.62 ± 6.63 years and 64.4% of the patients were male. The prevalence of MI with normal or near-normal coronary arteries was 3.5% (CI = 95%, min = 2.2%, and max = 5.7%. Additionally, smoking and family history of cardiovascular diseases were the most important risk factors. The results showed no significant difference between MIs with normal angiography and 1- or 2-vessel involvement regarding the frequency of major adverse cardiac events (5.4% vs. 7.3%, P = 0.32. However, a significant difference was found between the patients with normal angiography and those with 3-vessel involvement in this regard (5.4% vs. 20.2%, P < 0.001. Conclusions: Although angiographic studies are required to assess the underlying

  11. Precision-Recall-Gain Curves:PR Analysis Done Right

    Flach, Peter; Kull, Meelis

    2015-01-01

    Precision-Recall analysis abounds in applications of binary classification where true negatives do not add value and hence should not affect assessment of the classifier's performance. Perhaps inspired by the many advantages of receiver operating characteristic (ROC) curves and the area under such curves for accuracy-based performance assessment, many researchers have taken to report Precision-Recall (PR) curves and associated areas as performance metric. We demonstrate in this paper that thi...

  12. Theoretical foundations for environmental Kuznets curve analysis

    Lantz, Van

    This thesis provides a dynamic theory for analyzing the paths of aggregate output and pollution in a country over time. An infinite horizon, competitive growth-pollution model is explored in order to determine the role that economic scale, production techniques, and pollution regulations play in explaining the inverted U-shaped relationship between output and some forms of pollution (otherwise known as the Environmental Kuznets Curve, or EKC). Results indicate that the output-pollution relationship may follow a strictly increasing, strictly decreasing (but bounded), inverted U-shaped, or some combination of curves. While the 'scale' effect may cause output and pollution to exhibit a monotonic relationship, 'technique' and 'regulation' effects may ultimately cause a de-linking of these two variables. Pollution-minimizing energy regulation policies are also investigated within this framework. It is found that the EKC may be 'flattened' or even eliminated moving from a poorly-regulated economy to one that minimizes pollution. The model is calibrated to the US economy for output (gross national product, GNP) and two pollutants (sulfur dioxide, SO2, and carbon dioxide, CO2) over the period 1900 to 1990. Results indicate that the model replicates the observations quite well. The predominance of 'scale' effects cause aggregate SO2 and CO2 levels to increase with GNP in the early stages of development. Then, in the case of SO 2, 'technique' and 'regulation' effects may be the cause of falling SO2 levels with continued economic growth (establishing the EKC). CO2 continues to monotonically increase as output levels increase over time. The positive relationship may be due to the lack of regulations on this pollutant. If stricter regulation policies were instituted in the two case studies, an improved allocation of resources may result. While GNP may be 2.596 to 20% lower than what has been realized in the US economy (depending on the pollution variable analyzed), individual

  13. CT and angiographic analysis of posterior communicating artery aneurysms: What factors influence the amount of subarachnoid blood?

    Kim, Young Min; Jung, Kun Sik; Rho, Myung Ho; Choi, Pil Youb; Sung, Young Soon; Kwon, Jae Soo; Lee, Sang Wook

    1998-01-01

    To determine how clinical and angiographic factors relate to the amount of subarachnoid blood detected by computerized tomography in patients with a ruptured aneurysm. Between January 1996 and December 1997, 22 patients with a posterior communicating artery aneurysm were retrospectively evaluated. Oval(three of four cases), funnel(both cases), and daughter-sac (four of five cases) types of aneurysmal sac were found among the 13 patients with a large amount of subarachnoid blood;eight of these had a past history of hyertension or diabetes. Seven of eleven cases of cylindricaltype aneurysmal sac were found among the 9 patients with a small amount of sularachnoid blood;eight of these had no past history of hypertension or diabetes. The average S/N ratio (ratio of maximum sac length to neck diameter) of patients with a small amount of blood was higher than that of patients with a large amount of blood(2.72 vs 2.07). Although many factors influence the amount of subarachnoid blood in an aneurysmal rupture, we found that a large amount of blood was frequently present in the oval, funnel and daughter sac types of aneurysm, when S/N ratio was low, and when an underlying disease such as hypertension or diabetes was present. Conversely, a small amount of blood was present in the cylindrical type, when S/N ratio was high, and where there was no underlying disease.=20

  14. Advanced 2-dimensional quantitative coronary angiographic analysis for prediction of fractional flow reserve in intermediate coronary stenoses.

    Opolski, Maksymilian P; Pregowski, Jerzy; Kruk, Mariusz; Kepka, Cezary; Staruch, Adam D; Witkowski, Adam

    2014-07-01

    The widespread clinical application of coronary computed tomography angiography (CCTA) has resulted in increased referral patterns of patients with intermediate coronary stenoses to invasive coronary angiography. We evaluated the application of advanced quantitative coronary angiography (A-QCA) for predicting fractional flow reserve (FFR) in intermediate coronary lesions detected on CCTA. Fifty-six patients with 66 single intermediate coronary lesions (≥ 50% to 80% stenosis) on CCTA prospectively underwent coronary angiography and FFR. A-QCA including calculation of the Poiseuille-based index defined as the ratio of lesion length to the fourth power of the minimal lumen diameter (MLD) was performed. Significant stenosis was defined as FFR ≤ 0.80. The mean FFR was 0.86 ± 0.09, and 18 lesions (27%) were functionally significant. FFR correlated with lesion length (R=-0.303, P=0.013), MLD (R=0.527, P44%, and >69%, respectively (maximum negative predictive value of 94% for MLA, maximum positive predictive value of 58% for diameter stenosis). The Poiseuille-based index was the most accurate (C statistic 0.86, sensitivity 100%, specificity 71%, positive predictive value 56%, and negative predictive value 100%) predictor of FFR ≤ 0.80, but showed the lowest interobserver agreement (intraclass correlation coefficient 0.37). A-QCA might be used to rule out significant ischemia in intermediate stenoses detected by CCTA. The diagnostic application of the Poiseuille-based angiographic index is precluded by its high interobserver variability.

  15. Seismic Fragility Curves of Industrial Buildings by Using Nonlinear Analysis

    Mohamed Nazri Fadzli

    2017-01-01

    Full Text Available This study presents the steel fragility curves and performance curves of industrial buildings of different geometries. The fragility curves were obtained for different building geometries, and the performance curves were developed based on lateral load, which is affected by the geometry of the building. Three records of far-field ground motion were used for incremental dynamic analysis (IDA, and the design lateral loads for pushover analysis (POA. All designs were based on British Standard (BS 5950; however, Eurocode 8 was preferred for seismic consideration in the analysis because BS 5950 does not specify any seismic provision. The five levels of performance stated by FEMA-273, namely, operational phase, immediate occupancy, damage control, life safety, and collapse prevention (CP were used as main guidelines for evaluating structural performance. For POA, Model 2 had highest base shear, followed by Model 1 and Model 3, even though Model 2 has a smaller structure compared with Model 3. Meanwhile, the fragility curves showed that the probability of reaching or exceeding the CP level of Model 2 is the highest, followed by that of Models 1 and 3.

  16. Angiographic findings of congenital vascular malformation in soft tissue

    Choi, Dae Seob; Park, Jae Hyung; Han, Joon Koo; Chung, Jin Wook; Moon, Woo Kyung; Han, Man Chung

    1994-01-01

    We evaluated the clinical, plain radiographic, and angiographic findings of congenital vascular malformation of the soft tissue. Retrospective analysis was performed in 36 patients. Pathological diagnosis was done in 25 patients by surgery and the others were clinically and angiographically diagnosed. On the basis of angiographic findings, we classified the lesions to three groups as arteriovenous malformation (AVM), hemangioma, and venous malformation. In pathologically proven 25 cases, we compared the angiographic diagnosis with the pathologic diagnosis. By angiographic classification, AVM was 13 cases, hemangioma 16 cases, and venous malformation 7 cases. The locations of the lesions were upper extremities in 14 cases, lower extremities in 20 cases, both extremities in 1 case, and back in 1 case. Clinical findings were bruit and thrill in 13 cases(12 AVMs,1 hemangioma) and varicosities in 16 cases(11 AVMs, 3 hemangiomas and 2 venous malformations). The varicosities in AVM were pulsating nature, but not in hemangioma and venous malformation. The concordance rate of the angiographic and pathologic diagnosis was 100%(6/6) in AVM, 71%(10/14) in hemangioma and 60% (3/5) in venous malformation. We think that angiography is an essential study for accurate diagnosis and appropriate treatment of congenital vascular malformation

  17. Photometric Observation and Light Curve Analysis of Binary System ...

    2016-01-27

    Jan 27, 2016 ... Photometric Observation and Light Curve Analysis of Binary System ER-Orionis ... February to April 2008 with the 51 cm telescope of Biruni Observatory of Shiraz University in U, B and V filters (Johnson system) and an RCA 4509 photomultiplier. ... Articles are also visible in Web of Science immediately.

  18. Pooled analysis of the CONFIRM registries: impact of gender on procedure and angiographic outcomes in patients undergoing orbital atherectomy for peripheral artery disease.

    Lee, Michael S; Canan, Timothy; Rha, Seung-Woon; Mustapha, Jihad; Adams, George L

    2015-02-01

    To compare the acute procedure and angiographic outcomes of peripheral artery disease (PAD) patients treated with orbital atherectomy stratified by gender. The CONFIRM I, II, and III registries are US multicenter, nonrandomized, all-comers registries of PAD patients who were treated with orbital atherectomy. All patients with gender specified in the registry database were included in the current analysis, which compared the final residual stenosis achieved after atherectomy and the rate of acute complications in female and male patients. The 3 registries included 3131 patients with 4761 lesions: 1261 women (mean age 73.2 ± 10.7 years) with 1874 lesions and 1870 men (mean age 70.4 ± 10.2) with 2887 lesions. The women were older (p atherectomy in both men and women; however, women had a higher rate of dissection (all types). This difference is likely because of the older age and higher percentage of critical limb ischemia in women in this cohort. These results, however, suggest that additional studies should be completed to further understand the increased risks for women vs. men during endovascular procedures. © The Author(s) 2015.

  19. Analysis of power curves of Danish and foreign wind turbines

    Petersen, H.

    1995-12-01

    This report describes an analysis of power curves for a number of wind turbines, 30 Danish and 17 foreign - European - wind turbines. The investigation is limited to wind turbines of 150 kW capacity and greater, and to wind turbines for which a power curve is available. The power curves are transformed into a common, uniform presentation in order to facilitate the succeeding treatment, which primarily is the calculation of the production of electrical energy yielded per year. From the known data of the wind turbine, equipped generator power and rotor area and the area swept by the blades, the specific electrical production is calculated in three terms: yield per square meter of rotor area, yield per kW generator power and yield per square meter and per kilowatt generator power. Based on these findings a number of comparisons are established, such as comparisons of conceptual designs and technical- economical evaluations. (au)

  20. Use of universal functional optimisation for TL glow curve analysis

    Pernicka, F.; Linh, H.Q.

    1996-01-01

    The effective use of any TL instrument requires an efficient software package to be able to fulfil different tasks required by research and practical applications. One of the standard features of the package used at the NPI Prague is the application of the interactive modular system Universal Functional Optimisation (UFO) for glow curve deconvolution. The whole system has been tested on standard glow curves using different models of the TL process (a single peak described by the Podgorsak approximation, first order kinetics and/or general order kinetics). Calculated values of basic TL parameters (E and s) show a good agreement with the results obtained by other authors. The main advantage of the system is in its modularity that enables flexible changes in the TL model and mathematical procedures of the glow curve analysis. (author)

  1. Radiation dose during angiographic procedures

    Lavoie, Ch.; Rasuli, P.

    2001-01-01

    The use of angiographic procedures is becoming more prevalent as new techniques and equipment are developed. There have been concerns in the scientific community about the level of radiation doses received by patients, and indirectly by staff, during some of these radiological procedures. The purpose of this study was to assess the level of radiation dose from angiographic procedures to patient at the Ottawa Hospital, General Campus. Radiation dose measurements, using Thermo-Luminescent Dosimeters (TLDs), were performed on more than 100 patients on various procedures. The results show that while the patient dose from the great majority of angiographic procedures is less than 2 Gy, a significant number of procedures, especially interventional procedures may have doses greater than 2 Gy and may lead to deterministic effects. (author)

  2. PMAnalyzer: a new web interface for bacterial growth curve analysis.

    Cuevas, Daniel A; Edwards, Robert A

    2017-06-15

    Bacterial growth curves are essential representations for characterizing bacteria metabolism within a variety of media compositions. Using high-throughput, spectrophotometers capable of processing tens of 96-well plates, quantitative phenotypic information can be easily integrated into the current data structures that describe a bacterial organism. The PMAnalyzer pipeline performs a growth curve analysis to parameterize the unique features occurring within microtiter wells containing specific growth media sources. We have expanded the pipeline capabilities and provide a user-friendly, online implementation of this automated pipeline. PMAnalyzer version 2.0 provides fast automatic growth curve parameter analysis, growth identification and high resolution figures of sample-replicate growth curves and several statistical analyses. PMAnalyzer v2.0 can be found at https://edwards.sdsu.edu/pmanalyzer/ . Source code for the pipeline can be found on GitHub at https://github.com/dacuevas/PMAnalyzer . Source code for the online implementation can be found on GitHub at https://github.com/dacuevas/PMAnalyzerWeb . dcuevas08@gmail.com. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press.

  3. The Kepler Light Curves of AGN: A Detailed Analysis

    Smith, Krista Lynne; Mushotzky, Richard F.; Boyd, Patricia T.; Malkan, Matt; Howell, Steve B.; Gelino, Dawn M.

    2018-04-01

    We present a comprehensive analysis of 21 light curves of Type 1 active galactic nuclei (AGN) from the Kepler spacecraft. First, we describe the necessity and development of a customized pipeline for treating Kepler data of stochastically variable sources like AGN. We then present the light curves, power spectral density functions (PSDs), and flux histograms. The light curves display an astonishing variety of behaviors, many of which would not be detected in ground-based studies, including switching between distinct flux levels. Six objects exhibit PSD flattening at characteristic timescales that roughly correlate with black hole mass. These timescales are consistent with orbital timescales or free-fall accretion timescales. We check for correlations of variability and high-frequency PSD slope with accretion rate, black hole mass, redshift, and luminosity. We find that bolometric luminosity is anticorrelated with both variability and steepness of the PSD slope. We do not find evidence of the linear rms–flux relationships or lognormal flux distributions found in X-ray AGN light curves, indicating that reprocessing is not a significant contributor to optical variability at the 0.1%–10% level.

  4. Developmental trajectories of adolescent popularity: a growth curve modelling analysis.

    Cillessen, Antonius H N; Borch, Casey

    2006-12-01

    Growth curve modelling was used to examine developmental trajectories of sociometric and perceived popularity across eight years in adolescence, and the effects of gender, overt aggression, and relational aggression on these trajectories. Participants were 303 initially popular students (167 girls, 136 boys) for whom sociometric data were available in Grades 5-12. The popularity and aggression constructs were stable but non-overlapping developmental dimensions. Growth curve models were run with SAS MIXED in the framework of the multilevel model for change [Singer, J. D., & Willett, J. B. (2003). Applied longitudinal data analysis. Oxford, UK: Oxford University Press]. Sociometric popularity showed a linear change trajectory; perceived popularity showed nonlinear change. Overt aggression predicted low sociometric popularity but an increase in perceived popularity in the second half of the study. Relational aggression predicted a decrease in sociometric popularity, especially for girls, and continued high-perceived popularity for both genders. The effect of relational aggression on perceived popularity was the strongest around the transition from middle to high school. The importance of growth curve models for understanding adolescent social development was discussed, as well as specific issues and challenges of growth curve analyses with sociometric data.

  5. Empirical Analysis on The Existence of The Phillips Curve

    Shaari Mohd Shahidan

    2018-01-01

    Full Text Available The Phillips curve shows the trade-off relationship between the inflation and unemployment rates. A rise in inflation due to the high economic growth, more jobs are available and therefore unemployment will fall. However, the existence of the Phillips curve in high-income countries has not been much discussed. Countries with high income should have low unemployment rate, suggesting a high inflation. However, some high-income countries, the United States in 1970s for example, could not avert stagflation whereby high unemployment rate and inflation occurred in the same time. This situation is contrary to the Phillips curve. Therefore, this study aims to investigate the existence of the Phillips curve in high-income countries for the period 1990-2014 using the panel data analysis. The most interesting finding of this study is the existence of a bidirectional relationship between unemployment rate and inflation rate in both long and short runs. Therefore, the governments should choose to stabilize inflation rate or reduce unemployment rate

  6. An angiographic technique for coronary fractional flow reserve measurement: in vivo validation.

    Takarada, Shigeho; Zhang, Zhang; Molloi, Sabee

    2013-03-01

    Fractional flow reserve (FFR) is an important prognostic determinant in a clinical setting. However, its measurement currently requires the use of invasive pressure wire, while an angiographic technique based on first-pass distribution analysis and scaling laws can be used to measure FFR using only image data. Eight anesthetized swine were instrumented with flow probe on the proximal segment of the left anterior descending (LAD) coronary arteries. Volumetric blood flow from the flow probe (Qp), coronary pressure (Pa) and right atrium pressure (Pv) were continuously recorded. Flow probe-based FFR (FFRq) was measured from the ratio of flow with and without stenosis. To determine the angiography-based FFR (FFRa), the ratio of blood flow in the presence of a stenosis (QS) to theoretically normal blood flow (QN) was calculated. A region of interest in the LAD arterial bed was drawn to generate time-density curves using angiographic images. QS was measured using a time-density curve and the assumption that blood was momentarily replaced with contrast agent during the injection. QN was estimated from the total coronary arterial volume using scaling laws. Pressure-wire measurements of FFR (FFRp), which was calculated from the ratio of distal coronary pressure (Pd) divided by proximal pressure (Pa), were continuously obtained during the study. A total of 54 measurements of FFRa, FFRp, and FFRq were taken. FFRa showed a good correlation with FFRq (FFRa = 0.97 FFRq +0.06, r(2) = 0.80, p < 0.001), although FFRp overestimated the FFRq (FFRp = 0.657 FFRq + 0.313, r(2) = 0.710, p < 0.0001). Additionally, the Bland-Altman analysis showed a close agreement between FFRa and FFRq. This angiographic technique to measure FFR can potentially be used to evaluate both anatomical and physiological assessments of a coronary stenosis during routine diagnostic cardiac catheterization that requires no pressure wires.

  7. Stress analysis in curved composites due to thermal loading

    Polk, Jared Cornelius

    Many structures in aircraft, cars, trucks, ships, machines, tools, bridges, and buildings, consist of curved sections. These sections vary from straight line segments that have curvature at either one or both ends, segments with compound curvatures, segments with two mutually perpendicular curvatures or Gaussian curvatures, and segments with a simple curvature. With the advancements made in multi-purpose composites over the past 60 years, composites slowly but steadily have been appearing in these various vehicles, compound structures, and buildings. These composite sections provide added benefits over isotropic, polymeric, and ceramic materials by generally having a higher specific strength, higher specific stiffnesses, longer fatigue life, lower density, possibilities in reduction of life cycle and/or acquisition cost, and greater adaptability to intended function of structure via material composition and geometry. To be able to design and manufacture a safe composite laminate or structure, it is imperative that the stress distributions, their causes, and effects are thoroughly understood in order to successfully accomplish mission objectives and manufacture a safe and reliable composite. The objective of the thesis work is to expand upon the knowledge of simply curved composite structures by exploring and ascertaining all pertinent parameters, phenomenon, and trends in stress variations in curved laminates due to thermal loading. The simply curved composites consist of composites with one radius of curvature throughout the span of the specimen about only one axis. Analytical beam theory, classical lamination theory, and finite element analysis were used to ascertain stress variations in a flat, isotropic beam. An analytical method was developed to ascertain the stress variations in an isotropic, simply curved beam under thermal loading that is under both free-free and fixed-fixed constraint conditions. This is the first such solution to Author's best knowledge

  8. Coronary angiographic characteristics that influence fractional flow reserve.

    Natsumeda, Makoto; Nakazawa, Gaku; Murakami, Tsutomu; Torii, Sho; Ijichi, Takeshi; Ohno, Yohei; Masuda, Naoki; Shinozaki, Norihiko; Ogata, Nobuhiko; Yoshimachi, Fuminobu; Ikari, Yuji

    2015-01-01

    Percutaneous coronary intervention (PCI) guided with fractional flow reserve (FFR) has been shown to improve clinical outcome. Although coronary angiography is the standard method for PCI guidance, the visual severity of stenosis is not always correlated with functional severity, suggesting that there are additional angiographic factors that affect functional ischemia. To evaluate angiographic predictors of positive FFR in stenotic lesions, angiographic characteristics of 260 consecutive patients (362 lesions) who underwent FFR testing from April 2009 to September 2012 were analyzed. A scoring system (STABLED score) using these predictors was developed and compared with quantitative coronary angiography (QCA). %Diameter stenosis >50% (OR, 8.43; P20 mm (OR, 5.40; P=0.0002), and distance from ostium <20 mm (OR, 1.94; P=0.028) were determined as independent predictors of positive FFR. Area under the ROC curve for probability of positive FFR using the STABLED score (Stenosis 2 points, TAndem lesion 1 point, Bifurcation 1 point, LEsion length 1 point, Distance from ostium 1 point) was 0.85, higher than that for QCA stenosis alone (0.76). STABLED score ≥3 had 72.3% sensitivity and 83.6% specificity for predicting positive FFR, and PPV was 76.7%. Specific angiographic features are applicable for predicting functional ischemia. STABLED score correlates well with FFR.

  9. A Bayesian hierarchical model for demand curve analysis.

    Ho, Yen-Yi; Nhu Vo, Tien; Chu, Haitao; Luo, Xianghua; Le, Chap T

    2018-07-01

    Drug self-administration experiments are a frequently used approach to assessing the abuse liability and reinforcing property of a compound. It has been used to assess the abuse liabilities of various substances such as psychomotor stimulants and hallucinogens, food, nicotine, and alcohol. The demand curve generated from a self-administration study describes how demand of a drug or non-drug reinforcer varies as a function of price. With the approval of the 2009 Family Smoking Prevention and Tobacco Control Act, demand curve analysis provides crucial evidence to inform the US Food and Drug Administration's policy on tobacco regulation, because it produces several important quantitative measurements to assess the reinforcing strength of nicotine. The conventional approach popularly used to analyze the demand curve data is individual-specific non-linear least square regression. The non-linear least square approach sets out to minimize the residual sum of squares for each subject in the dataset; however, this one-subject-at-a-time approach does not allow for the estimation of between- and within-subject variability in a unified model framework. In this paper, we review the existing approaches to analyze the demand curve data, non-linear least square regression, and the mixed effects regression and propose a new Bayesian hierarchical model. We conduct simulation analyses to compare the performance of these three approaches and illustrate the proposed approaches in a case study of nicotine self-administration in rats. We present simulation results and discuss the benefits of using the proposed approaches.

  10. Statistical analysis of the W Cyg light curve

    Klyus, I.A.

    1983-01-01

    A statistical analysis of the light curve of W Cygni has been carried out. The process of brightness variations brightness of the star is shown to be a stationary stochastic one. The hypothesis of stationarity of the process was checked at the significance level of α=0.05. Oscillations of the brightness with average durations of 131 and 250 days have been found. It is proved that oscillations are narrow-band noise, i.e. cycles. Peaks on the power spectrum corresponding to these cycles exceed 99% confidence interval. It has been stated that the oscillations are independent

  11. A new approach to the analysis of Mira light curves

    Mennessier, M.O.; Barthes, D.; Mattei, J.A.

    1990-01-01

    Two different but complementary methods for predicting Mira luminosities are presented. One method is derived from a Fourier analysis, it requires performing deconvolution, and its results are not certain due to the inherent instability of deconvolution problems. The other method is a learning method utilizing artificial intelligence techniques where a light curve is presented as an ordered sequence of pseudocycles, and rules are learned by linking the characteristics of several consecutive pseudocycles to one characteristic of the future cycle. It is observed that agreement between these methods is obtainable when it is possible to eliminate similar false frequencies from the preliminary power spectrum and to improve the degree of confidence in the rules

  12. Adult Moyamoya disease angiographic images evolutive characters and treatment methods

    Qian Jiangnan; Ling Feng

    2000-01-01

    Objective: To discuss the angiographic images with evolutional characters and the treatment methods of the Moyamoya disease. Methods: The clinical manifestations, the radiographic changes and the comparative analysis between medicine treatment and surgery treatment, together with the laboratory tests findings were analyzed in one cases adult Moyamoya disease during six years. Conclusions: The angiographic characteristics of MMD show the supplied artery trunk stenosis, and followed by occlusion, with later appearance of vascular smoking sign. Medical treatment proved to be of null. Direct or indirect intra or extra cranial vascular anastomosis are effective for treatment

  13. Scintiscanning of arthritis and analysis of build-up curves

    Yamagishi, Tsuneo; Omori, Shigeo; Miyawaki, Haruo; Maniwa, Masato; Yoshizaki, Kenichi

    1975-01-01

    In the present study 40 knee joints with rheumatoid arthritis, 23 knee joints with osteoarthrosis deformans, 3 knee joints with non-synovitis, one knee joint with pyogenic arthritis and 4 normal knee joints were scanned. By analysis of build-up curves obtained immediately after the intravenous injection of sup(99m)Tc-pertechnetate, the rate of accumulation of radioactivity (t 1/2) in the affected joints was simultaneously estimated in order to compare them with clinical findings. 1. Scintiscanning of arthritis, rheumatoid arthritis, osteoarthrosis deformans of the knee joint, non-specific synovitis, and pyogenic arthritis of the knee joint, yielded a positive scan for all of the joint diseases. 2. In the scintigram of healthy knee joints, there are no areas of RI accumulation or right to left difference. 3. In some instances abnormal uptake of RI was seen on scintigrams of arthritis even after normal clinical and laboratory findings had been achieved with therapy. 4. sup(99m)Tc-pertechnetate, a radionuclide with a short half-life, allows repeated scans and provides a useful radiologic means of evaluating therapeutic course and effectiveness. 5. Analysis of build-up curves revealed that the rate of accumulation of RI was faster in rheumatoid arthritis than in osteoarthrosis deformans. (auth.)

  14. Analysis of velocity planning interpolation algorithm based on NURBS curve

    Zhang, Wanjun; Gao, Shanping; Cheng, Xiyan; Zhang, Feng

    2017-04-01

    To reduce interpolation time and Max interpolation error in NURBS (Non-Uniform Rational B-Spline) inter-polation caused by planning Velocity. This paper proposed a velocity planning interpolation algorithm based on NURBS curve. Firstly, the second-order Taylor expansion is applied on the numerator in NURBS curve representation with parameter curve. Then, velocity planning interpolation algorithm can meet with NURBS curve interpolation. Finally, simulation results show that the proposed NURBS curve interpolator meet the high-speed and high-accuracy interpolation requirements of CNC systems. The interpolation of NURBS curve should be finished.

  15. Fourier analysis of the light curves of eclipsing variables, XXIV

    Edalati, M.T.

    1978-01-01

    The aim of the present paper will be to evaluate numerically Jacobian and other functions which have been discussed in more detail in a previous paper of this series, and also choose the most convenient moments to obtain a good determination for the unknown eclipse parameters a and c 0 . More than 12 different pairs of g-functions for real values of m have been investigated numerically and diagrammatically. The behaviour of g-functions depends but very little on different combination of the moments, and related diagrams are approximately the same as g 2 and g 4 . The behaviour of the vanishing Jacobian, arising from different pairs of g-functions for real values of m>= 0 . Accordingly, the author obtains the optimum combination of the moments (i.e., A 6 , A 7 , A 8 and A 9 ) in g-functions g 7 and g 8 . It has been noted that the behaviour of the g-functions which depend on the combinations of the higher order moments (i.e., m>= 5) have been ruled out, because the proportional error of the moments Asub(2m) increases with increasing values of real m. The automated method has been tested successfully on the light curve of RT Per. Finally, a comparison is given of the elements of RT Per arising from two different pairs of g-functions, i.e. g 2 , g 4 and g 7 , g 8 for the light curves analysis. (Auth.)

  16. Electromagnetic and structural interaction analysis of curved shell structures

    Horie, T.; Niho, T.

    1993-01-01

    This paper describes a finite element formulation of the eddy current and structure coupled problem for curved shell structures. Coupling terms produced by curved geometry as well as flat plate geometry were obtained. Both matrix equations for eddy current and structure were solved simultaneously using coupling sub-matrices. TEAM Workshop bench mark problem 16 was solved to verify the formulation and the computer code. Agreement with experimental results was very good for such plate problem. A coupled problem for cylindrical shell structure was also analyzed. Influence of each coupling term was examined. The next topic is the eigenvalues of the coupled equations. Although the coupled matrix equations are not symmetric, symmetry was obtained by introducing a symmetrizing variable. The eigenvalues of the coupled matrix equations are different from those obtained from the uncoupled equations because of the influence of the coupling sub-matrix components. Some parameters obtained by the eigenvalue analysis have characteristics of parameters which indicate the intensity of electromagnetic structural coupling effect. (author)

  17. Analysis of interacting quantum field theory in curved spacetime

    Birrell, N.D.; Taylor, J.G.

    1980-01-01

    A detailed analysis of interacting quantized fields propagating in a curved background spacetime is given. Reduction formulas for S-matrix elements in terms of vacuum Green's functions are derived, special attention being paid to the possibility that the ''in'' and ''out'' vacuum states may not be equivalent. Green's functions equations are obtained and a diagrammatic representation for them given, allowing a formal, diagrammatic renormalization to be effected. Coordinate space techniques for showing renormalizability are developed in Minkowski space, for lambdaphi 3 /sub() 4,6/ field theories. The extension of these techniques to curved spacetimes is considered. It is shown that the possibility of field theories becoming nonrenormalizable there cannot be ruled out, although, allowing certain modifications to the theory, phi 3 /sub( 4 ) is proven renormalizable in a large class of spacetimes. Finally particle production from the vacuum by the gravitational field is discussed with particular reference to Schwarzschild spacetime. We shed some light on the nonlocalizability of the production process and on the definition of the S matrix for such processes

  18. Growth Curve Analysis and Change-Points Detection in Extremes

    Meng, Rui

    2016-05-15

    The thesis consists of two coherent projects. The first project presents the results of evaluating salinity tolerance in barley using growth curve analysis where different growth trajectories are observed within barley families. The study of salinity tolerance in plants is crucial to understanding plant growth and productivity. Because fully-automated smarthouses with conveyor systems allow non-destructive and high-throughput phenotyping of large number of plants, it is now possible to apply advanced statistical tools to analyze daily measurements and to study salinity tolerance. To compare different growth patterns of barley variates, we use functional data analysis techniques to analyze the daily projected shoot areas. In particular, we apply the curve registration method to align all the curves from the same barley family in order to summarize the family-wise features. We also illustrate how to use statistical modeling to account for spatial variation in microclimate in smarthouses and for temporal variation across runs, which is crucial for identifying traits of the barley variates. In our analysis, we show that the concentrations of sodium and potassium in leaves are negatively correlated, and their interactions are associated with the degree of salinity tolerance. The second project studies change-points detection methods in extremes when multiple time series data are available. Motived by the scientific question of whether the chances to experience extreme weather are different in different seasons of a year, we develop a change-points detection model to study changes in extremes or in the tail of a distribution. Most of existing models identify seasons from multiple yearly time series assuming a season or a change-point location remains exactly the same across years. In this work, we propose a random effect model that allows the change-point to vary from year to year, following a given distribution. Both parametric and nonparametric methods are developed

  19. The Environmental Kuznets Curve. An empirical analysis for OECD countries

    Georgiev, E.

    2008-09-15

    This paper tests the Environmental Kuznets Curve hypothesis for four local (SOx, NOx, CO, VOC) and two global (CO2, GHG) air pollutants. Using a new panel data set of thirty OECD countries, the paper finds that the postulated inverted U-shaped relationship between income and pollution does not hold for all gases. A meaningful Environmental Kuznets Curve exists only for CO, VOC and NOx, where for CO2 the curve is monotonically increasing. For GHG there is indication of an inverted U-shaped relationship between income and pollution, but still most countries are on the increasing path of the curve and hence the future development of the curve is uncertain. For SOx it was found that emissions follow an U-shaped curve. Based on the empirical results, the paper concludes that the Environmental Kuznets Curve does not hold for all gases, it is rather an empirical artefact than a regularity.

  20. The Environmental Kuznets Curve. An empirical analysis for OECD countries

    Georgiev, E.

    2008-09-01

    This paper tests the Environmental Kuznets Curve hypothesis for four local (SOx, NOx, CO, VOC) and two global (CO2, GHG) air pollutants. Using a new panel data set of thirty OECD countries, the paper finds that the postulated inverted U-shaped relationship between income and pollution does not hold for all gases. A meaningful Environmental Kuznets Curve exists only for CO, VOC and NOx, where for CO2 the curve is monotonically increasing. For GHG there is indication of an inverted U-shaped relationship between income and pollution, but still most countries are on the increasing path of the curve and hence the future development of the curve is uncertain. For SOx it was found that emissions follow an U-shaped curve. Based on the empirical results, the paper concludes that the Environmental Kuznets Curve does not hold for all gases, it is rather an empirical artefact than a regularity.

  1. Learning curve analysis of mitral valve repair using telemanipulative technology.

    Charland, Patrick J; Robbins, Tom; Rodriguez, Evilio; Nifong, Wiley L; Chitwood, Randolph W

    2011-08-01

    To determine if the time required to perform mitral valve repairs using telemanipulation technology decreases with experience and how that decrease is influenced by patient and procedure variables. A single-center retrospective review was conducted using perioperative and outcomes data collected contemporaneously on 458 mitral valve repair surgeries using telemanipulative technology. A regression model was constructed to assess learning with this technology and predict total robot time using multiple predictive variables. Statistical analysis was used to determine if models were significantly useful, to rule out correlation between predictor variables, and to identify terms that did not contribute to the prediction of total robot time. We found a statistically significant learning curve (P learning percentage∗ derived from total robot times† for the first 458 recorded cases of mitral valve repair using telemanipulative technology is 95% (R(2) = .40). More than one third of the variability in total robot time can be explained through our model using the following variables: type of repair (chordal procedures, ablations, and leaflet resections), band size, use of clips alone in band implantation, and the presence of a fellow at bedside (P Learning in mitral valve repair surgery using telemanipulative technology occurs at the East Carolina Heart Institute according to a logarithmic curve, with a learning percentage of 95%. From our regression output, we can make an approximate prediction of total robot time using an additive model. These metrics can be used by programs for benchmarking to manage the implementation of this new technology, as well as for capacity planning, scheduling, and capital budget analysis. Copyright © 2011 The American Association for Thoracic Surgery. All rights reserved.

  2. Angiographic findings of hepatocellular carcinoma

    Han, Man Chung; Cho, Byung Jae; Huh, Seung Jae; Bae, Sang Hoon; Kim, Ung Jin; Kim, Chung Yong; Kim, Noe Kyeong [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1985-12-15

    From March 1977 to July 1979, 69 cases of angiograms of hepatocellular carcinoma were observed in Seoul National University Hospital. The findings of selective celiac and/or hepatic arteriography in total 69 cases of confirmed hepatocellular carcinoma, with clinical and laboratory findings, were analyzed. The summarized results are as follows; 1. Among 69 cases od hepatoma, 62 were male and 7 were female with sex ratio of 8.9 : 1. Peak incidence is 5th to 7th decades (72.5%). Epigastric pain, indigestion, and palpable mass in right upper quadrant were common symptoms and sign. Laboratory findings showed elevated serum alkaline phosphatase more than 5 Bodansky unit in 75.4%. Alpha-feto protein was positive in 65.2% of all the patients. 2 All 69 cases were classified into 31 cases of massive type, 22 cases of diffuse type, and 16 cases of nodular type, in accordance with angiographic gross anatomy. The frequency of angiographic findings were hypervascularities and tumor vessels (100%), tumor stainings (98.5%), arteriovenous shunt (71.0%), displacement of intrahepatic arteries (66.7%), vascular lakes and channel (59.4%). Encasement of hepatic artery and portal vein regurgitation was respectively 4 cases. Tumor mass in portal vein were 6 cases and tumor mass in hepatic vein was 1 case. 3. Intraarterial infusion of 5-FU was performed in 15 hepatoma patients, and the results were that angiographic improvement was demonstrated in 3 cases, no improvement in 8 cases, and incomplete infusion in 4 cases. 4. The selective celiac and/or hepatic angiograms are excellent diagnostic tools as well as therapeutic management for intraarterial infusion of anticancerous drugs.

  3. Angiographic findings of hepatocellular carcinoma

    Han, Man Chung; Cho, Byung Jae; Huh, Seung Jae; Bae, Sang Hoon; Kim, Ung Jin; Kim, Chung Yong; Kim, Noe Kyeong

    1985-01-01

    From March 1977 to July 1979, 69 cases of angiograms of hepatocellular carcinoma were observed in Seoul National University Hospital. The findings of selective celiac and/or hepatic arteriography in total 69 cases of confirmed hepatocellular carcinoma, with clinical and laboratory findings, were analyzed. The summarized results are as follows; 1. Among 69 cases od hepatoma, 62 were male and 7 were female with sex ratio of 8.9 : 1. Peak incidence is 5th to 7th decades (72.5%). Epigastric pain, indigestion, and palpable mass in right upper quadrant were common symptoms and sign. Laboratory findings showed elevated serum alkaline phosphatase more than 5 Bodansky unit in 75.4%. Alpha-feto protein was positive in 65.2% of all the patients. 2 All 69 cases were classified into 31 cases of massive type, 22 cases of diffuse type, and 16 cases of nodular type, in accordance with angiographic gross anatomy. The frequency of angiographic findings were hypervascularities and tumor vessels (100%), tumor stainings (98.5%), arteriovenous shunt (71.0%), displacement of intrahepatic arteries (66.7%), vascular lakes and channel (59.4%). Encasement of hepatic artery and portal vein regurgitation was respectively 4 cases. Tumor mass in portal vein were 6 cases and tumor mass in hepatic vein was 1 case. 3. Intraarterial infusion of 5-FU was performed in 15 hepatoma patients, and the results were that angiographic improvement was demonstrated in 3 cases, no improvement in 8 cases, and incomplete infusion in 4 cases. 4. The selective celiac and/or hepatic angiograms are excellent diagnostic tools as well as therapeutic management for intraarterial infusion of anticancerous drugs.

  4. ESTIMATING TORSION OF DIGITAL CURVES USING 3D IMAGE ANALYSIS

    Christoph Blankenburg

    2016-04-01

    Full Text Available Curvature and torsion of three-dimensional curves are important quantities in fields like material science or biomedical engineering. Torsion has an exact definition in the continuous domain. However, in the discrete case most of the existing torsion evaluation methods lead to inaccurate values, especially for low resolution data. In this contribution we use the discrete points of space curves to determine the Fourier series coefficients which allow for representing the underlying continuous curve with Cesàro’s mean. This representation of the curve suits for the estimation of curvature and torsion values with their classical continuous definition. In comparison with the literature, one major advantage of this approach is that no a priori knowledge about the shape of the cyclic curve parts approximating the discrete curves is required. Synthetic data, i.e. curves with known curvature and torsion, are used to quantify the inherent algorithm accuracy for torsion and curvature estimation. The algorithm is also tested on tomographic data of fiber structures and open foams, where discrete curves are extracted from the pore spaces.

  5. Magneto-electro-elastic buckling analysis of nonlocal curved nanobeams

    Ebrahimi, Farzad; Reza Barati, Mohammad

    2016-09-01

    In this work, a size-dependent curved beam model is developed to take into account the effects of nonlocal stresses on the buckling behavior of curved magneto-electro-elastic FG nanobeams for the first time. The governing differential equations are derived based on the principle of virtual work and Euler-Bernoulli beam theory. The power-law function is employed to describe the spatially graded magneto-electro-elastic properties. By extending the radius of the curved nanobeam to infinity, the results of straight nonlocal FG beams can be rendered. The effects of magnetic potential, electric voltage, opening angle, nonlocal parameter, power-law index and slenderness ratio on buckling loads of curved MEE-FG nanobeams are studied.

  6. An analysis on the environmental Kuznets curve of Chengdu

    Gao, Zijian; Peng, Yue; Zhao, Yue

    2017-12-01

    In this paper based on the environmental and economic data of Chengdu from 2005 to 2014, the measurement models were established to analyze 3 kinds of environmental flow indicators and 4 kinds of environmental stock indicators to obtain their EKC evolution trajectories and characters. The results show that the relationship curve between the discharge of SO2 from industry and the GDP per capita is a positive U shape, just as the curve between discharge of COD from industry and the GDP per person. The relationship curve between the dust discharge from industry and the GDP per capita is an inverted N shape. In the central of the urban the relationship curve between the concentration of SO2 in the air and the GDP per person is a positive U shape. The relationship curves between the concentration of NO2 in the air and the GDP per person, between the concentration of the particulate matters and the GDP per person, and between the concentration of the fallen dusts and the GDP per person are fluctuating. So the EKC curves of the 7 kinds of environmental indicators are not accord with inverted U shape feature. In the development of this urban the environmental problems can’t be resolved only by economic growth. The discharge of industrial pollutants should be controlled to improve the atmospheric environmental quality and reduce the environmental risks.

  7. Simultaneity modeling analysis of the environmental Kuznets curve hypothesis

    Ben Youssef, Adel; Hammoudeh, Shawkat; Omri, Anis

    2016-01-01

    The environmental Kuznets curve (EKC) hypothesis has been recognized in the environmental economics literature since the 1990's. Various statistical tests have been used on time series, cross section and panel data related to single and groups of countries to validate this hypothesis. In the literature, the validation has always been conducted by using a single equation. However, since both the environment and income variables are endogenous, the estimation of a single equation model when simultaneity exists produces inconsistent and biased estimates. Therefore, we formulate simultaneous two-equation models to investigate the EKC hypothesis for fifty-six countries, using annual panel data from 1990 to 2012, with the end year is determined by data availability for the panel. To make the panel data analysis more homogeneous, we investigate this issue for a three income-based panels (namely, high-, middle-, and low-income panels) given several explanatory variables. Our results indicate that there exists a bidirectional causality between economic growth and pollution emissions in the overall panels. We also find that the relationship is nonlinear and has an inverted U-shape for all the considered panels. Policy implications are provided. - Highlights: • We have given a new look for the validity of the EKC hypothesis. • We formulate two-simultaneous equation models to validate this hypothesis for fifty-six countries. • We find a bidirectional causality between economic growth and pollution emissions. • We also discover an inverted U-shaped between environmental degradation and economic growth. • This relationship varies at different stages of economic development.

  8. Automatic generation and analysis of solar cell IV curves

    Kraft, Steven M.; Jones, Jason C.

    2014-06-03

    A photovoltaic system includes multiple strings of solar panels and a device presenting a DC load to the strings of solar panels. Output currents of the strings of solar panels may be sensed and provided to a computer that generates current-voltage (IV) curves of the strings of solar panels. Output voltages of the string of solar panels may be sensed at the string or at the device presenting the DC load. The DC load may be varied. Output currents of the strings of solar panels responsive to the variation of the DC load are sensed to generate IV curves of the strings of solar panels. IV curves may be compared and analyzed to evaluate performance of and detect problems with a string of solar panels.

  9. Phase Curve Analysis of Super-Earth 55 Cancri e

    Angelo, Isabel; Hu, Renyu

    2018-01-01

    One of the primary questions when characterizing Earth-sized and super-Earth-sized exoplanets is whether they have a substantial atmosphere like Earth and Venus, or a bare-rock surface that may come with a tenuous atmosphere like Mercury. Phase curves of the planets in thermal emission provide clues to this question, because a substantial atmosphere would transport heat more efficiently than a bare-rock surface. Analyzing phase curve photometric data around secondary eclipse has previously been used to study energy transport in the atmospheres of hot Jupiters. Here we use phase curve, Spitzer time-series photometry to study the thermal emission properties of the super-Earth exoplanet 55 Cancri e. We utilize a previously developed semi-analytical framework to fit a physical model to infrared photometric data of host star 55 Cancri from the Spitzer telescope IRAC 2 band at 4.5 μm. The model uses various parameters of planetary properties including Bond albedo, heat redistribution efficiency (i.e., the ratio between the radiative timescale and advective timescale of the photosphere), and atmospheric greenhouse factor. The phase curve of 55 Cancri e is dominated by thermal emission with an eastward-shifted hot spot located on the planet surface. We determine the heat redistribution efficiency to be ≈1.47, which implies that the advective timescale is on the same order as the radiative timescale. This requirement from the phase curve cannot be met by the bare-rock planet scenario, because heat transport by currents of molten lava would be too slow. The phase curve thus favors the scenario with a substantial atmosphere. Our constraints on the heat redistribution efficiency translate to a photosphere pressure of ~1.4 bar. The Spitzer IRAC 2 band is thus a window into the deep atmosphere of the planet 55 Cancri e.

  10. Mediation Analysis in a Latent Growth Curve Modeling Framework

    von Soest, Tilmann; Hagtvet, Knut A.

    2011-01-01

    This article presents several longitudinal mediation models in the framework of latent growth curve modeling and provides a detailed account of how such models can be constructed. Logical and statistical challenges that might arise when such analyses are conducted are also discussed. Specifically, we discuss how the initial status (intercept) and…

  11. Semiparametric analysis to estimate the deal effect curve

    Heerde, Harald J. van; Leeflang, Peter S.H.; Wittink, Dick R.

    1999-01-01

    The marketing literature suggests several phenomena that may contribute to the shape of the relationship between sales and price discounts. These phenomena can produce severe nonlinearities and interactions in the curves, and we argue that those are best captured with a flexible approach. Since a

  12. Semiparametric analysis to estimate the deal effect curve

    Van Heerde, HJ; Leeflang, PSH; Wittink, DR

    The marketing literature suggests several phenomena that may contribute to the nature of the relationship between sales and price discounts. These phenomena can produce complex nonlinearities and interactions in the deal effect curve that are best captured with a flexible approach. Because a fully

  13. The GO Cygni system: photoelectric observations and light curves analysis

    Rovithis, P.; Rovithis-Livaniou, H.; Niarchos, P.G.

    1990-01-01

    Photoelectric observations, in B and V, of the system GO Cygni obtained during 1985 at the Kryonerion Astronomical Station of the National Observatory of Greece are given. The corresponding light curves (typical β Lyrae) are analysed using Frequency Domain techniques. New photoelectric and absolute elements for the system are given, and its period was found to continue its increasing

  14. An algorithm for unified analysis on the thermoluminescence glow curve

    Chung, K.S.; Park, C.Y.; Lee, J.I.; Kim, J.L.

    2014-01-01

    An algorithm was developed to integrally handle excitation by radiation, relaxation and luminescence by thermal or optical stimulation in thermoluminescence (TL) and optically stimulated luminescence (OSL) processes. This algorithm reflects the mutual interaction between traps through a conduction band. Electrons and holes are created by radiation in the beginning, and these electrons move to the trap through the conduction band. These holes move to the recombination center through a valence band. The ratio of the electrons allocated to each trap differs with the recombination probability and these values also relevant to the process of luminescence. Accordingly, the glow curve can be interpreted by taking the rate of electron–hole pairs created by ionizing radiation as a unique initial condition. This method differs from the conventional method of interpreting the measured glow curve with the initial electron concentration allocated to each trap at the end of irradiation. A program using the Visual Studio's C# subsystem was made to realize such a developed algorithm. To verify this algorithm it was applied to LiF:Mg,Cu,Si. The TL glow curve was deconvoluted with a model of five traps, one deep trap and one recombination center (RC). - Highlights: • TL glow curve deconvolution employing interacting model. • Simulation both irradiation and TL readout stages for various dose level. • Application in the identification TL kinetics of LiF:Mg,Cu,Si TLD

  15. Photometric Observation and Light Curve Analysis of Binary System ...

    Abstract. Photometric observations of the over-contact binary ER ORI were performed during November 2007 and February to April 2008 with the 51cm telescope of Biruni Observatory of Shiraz University in U, B and V filters (Johnson system) and an RCA 4509 photomultiplier. We used these data to obtain the light curves ...

  16. UNSUPERVISED TRANSIENT LIGHT CURVE ANALYSIS VIA HIERARCHICAL BAYESIAN INFERENCE

    Sanders, N. E.; Soderberg, A. M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Betancourt, M., E-mail: nsanders@cfa.harvard.edu [Department of Statistics, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2015-02-10

    Historically, light curve studies of supernovae (SNe) and other transient classes have focused on individual objects with copious and high signal-to-noise observations. In the nascent era of wide field transient searches, objects with detailed observations are decreasing as a fraction of the overall known SN population, and this strategy sacrifices the majority of the information contained in the data about the underlying population of transients. A population level modeling approach, simultaneously fitting all available observations of objects in a transient sub-class of interest, fully mines the data to infer the properties of the population and avoids certain systematic biases. We present a novel hierarchical Bayesian statistical model for population level modeling of transient light curves, and discuss its implementation using an efficient Hamiltonian Monte Carlo technique. As a test case, we apply this model to the Type IIP SN sample from the Pan-STARRS1 Medium Deep Survey, consisting of 18,837 photometric observations of 76 SNe, corresponding to a joint posterior distribution with 9176 parameters under our model. Our hierarchical model fits provide improved constraints on light curve parameters relevant to the physical properties of their progenitor stars relative to modeling individual light curves alone. Moreover, we directly evaluate the probability for occurrence rates of unseen light curve characteristics from the model hyperparameters, addressing observational biases in survey methodology. We view this modeling framework as an unsupervised machine learning technique with the ability to maximize scientific returns from data to be collected by future wide field transient searches like LSST.

  17. UNSUPERVISED TRANSIENT LIGHT CURVE ANALYSIS VIA HIERARCHICAL BAYESIAN INFERENCE

    Sanders, N. E.; Soderberg, A. M.; Betancourt, M.

    2015-01-01

    Historically, light curve studies of supernovae (SNe) and other transient classes have focused on individual objects with copious and high signal-to-noise observations. In the nascent era of wide field transient searches, objects with detailed observations are decreasing as a fraction of the overall known SN population, and this strategy sacrifices the majority of the information contained in the data about the underlying population of transients. A population level modeling approach, simultaneously fitting all available observations of objects in a transient sub-class of interest, fully mines the data to infer the properties of the population and avoids certain systematic biases. We present a novel hierarchical Bayesian statistical model for population level modeling of transient light curves, and discuss its implementation using an efficient Hamiltonian Monte Carlo technique. As a test case, we apply this model to the Type IIP SN sample from the Pan-STARRS1 Medium Deep Survey, consisting of 18,837 photometric observations of 76 SNe, corresponding to a joint posterior distribution with 9176 parameters under our model. Our hierarchical model fits provide improved constraints on light curve parameters relevant to the physical properties of their progenitor stars relative to modeling individual light curves alone. Moreover, we directly evaluate the probability for occurrence rates of unseen light curve characteristics from the model hyperparameters, addressing observational biases in survey methodology. We view this modeling framework as an unsupervised machine learning technique with the ability to maximize scientific returns from data to be collected by future wide field transient searches like LSST

  18. Angiographic appearances of rare renal tumours

    Schmidt, M.; Taenzer, V.

    1980-01-01

    Oncocytomas, called oxyphil proximal tubular adenomas in the Anglo Saxon literature, and benign hypernephromas are non-malignant, usually symptomless, rare tumours belonging to the renal adenomas. Oncocytomas have angiographic appearances sufficiently uniform to permit a tentative diagnosis. Histologically benign hypernephromas do not possess characteristic angiographic appearances and, in the presence of tumour in the renal vein or necrotic avascular areas, must be regarded as potentially malignant. (orig.) [de

  19. Clinical and angiographic outcomes after stent-assisted coiling of cerebral aneurysms with Enterprise and Neuroform stents: a comparative analysis of the literature.

    King, Brent; Vaziri, Sasha; Singla, Amit; Fargen, Kyle M; Mocco, J

    2015-12-01

    The most widely used intracranial stents for stent-assisted coiling are Neuroform (NEU) and Enterprise stents (ENT). This study compares published outcomes between the ENT and NEU coil-assist systems and comments on the published safety and efficacy of stent-assisted coiling in general. A literature search was performed through PubMed for all published series of ENT or NEU stent-assisted coiling of cerebral aneurysms from 2004 to 2014. All studies including 10 or more published cases of stent-assisted coiling with ENT or NEU were included. 47 studies met the inclusion criteria, containing 4238 aneurysms in 4039 patients. 2111 aneurysms were treated with NEU and 2127 were treated with ENT. Mean follow-up was 14.1 months. Overall, thromboembolic events occurred in 6.4% of aneurysms, intracranial hemorrhage (ICH) in 2.6%, permanent morbidity in 3.9%, and mortality in 2.3%. Initial and final 100% angiographic occlusion was seen in 53% and 69% of patients, respectively. Deployment failures (pstent-assisted coiling devices to date, containing over 4200 aneurysms in more than 4000 patients. Comparative analyses demonstrate that both devices are reported to be safe and effective with comparable permanent morbidity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  20. Thermodynamic Activity-Based Progress Curve Analysis in Enzyme Kinetics.

    Pleiss, Jürgen

    2018-03-01

    Macrokinetic Michaelis-Menten models based on thermodynamic activity provide insights into enzyme kinetics because they separate substrate-enzyme from substrate-solvent interactions. Kinetic parameters are estimated from experimental progress curves of enzyme-catalyzed reactions. Three pitfalls are discussed: deviations between thermodynamic and concentration-based models, product effects on the substrate activity coefficient, and product inhibition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The learning curve: implications of a quantitative analysis.

    Gallistel, Charles R; Fairhurst, Stephen; Balsam, Peter

    2004-09-07

    The negatively accelerated, gradually increasing learning curve is an artifact of group averaging in several commonly used basic learning paradigms (pigeon autoshaping, delay- and trace-eye-blink conditioning in the rabbit and rat, autoshaped hopper entry in the rat, plus maze performance in the rat, and water maze performance in the mouse). The learning curves for individual subjects show an abrupt, often step-like increase from the untrained level of responding to the level seen in the well trained subject. The rise is at least as abrupt as that commonly seen in psychometric functions in stimulus detection experiments. It may indicate that the appearance of conditioned behavior is mediated by an evidence-based decision process, as in stimulus detection experiments. If the appearance of conditioned behavior is taken instead to reflect the increase in an underlying associative strength, then a negligible portion of the function relating associative strength to amount of experience is behaviorally visible. Consequently, rate of learning cannot be estimated from the group-average curve; the best measure is latency to the onset of responding, determined for each subject individually.

  2. Fourier analysis of the light curves of eclipsing variables. XV

    Demircan, O.

    1978-01-01

    A new general expression for the theoretical moments Asub(2m) of the light curves of eclipsing systems has been presented in the form of infinite series expansion. In this expansion, the terms have been given as the product of two different polynomials which satisfy certain three-term recursion formulae, and the coefficients diminish rapidly with increasing number of terms. Thus, the numerical values of the theoretical moments Asub(2m) can be generated recursively up to four significant figures for any given set of eclipse elements. This can be utilized to solve the eclipse elements in two ways: (i) with an indirect method, (ii) with a direct method as minimization to the observational moments Asub(2m) (area fitting). The procedures for obtaining the elements of any eclipsing system consisting of spherical stars have been automated by making use of the new expression for the moments Asub(2m) of the light curves. The theoretical functions f 0 , f 2 , f 4 , f 6 , g 2 and g 4 which are the functions of a and c 0 , have been used to solve the eclipse elements from the observed photometric data. The closed-form expressions for the functions f 2 , f 4 and f 6 have also been derived in terms of Kopal's I-integrals. The automated methods for obtaining the eclipse elements from one minimum alone have been tested on the light curves of YZ (21) Cassiopeiae under the spherical model assumptions. The results of these applications are given. (Auth.)

  3. Paleomagnetic analysis of curved thrust belts reproduced by physical models

    Costa, Elisabetta; Speranza, Fabio

    2003-12-01

    This paper presents a new methodology for studying the evolution of curved mountain belts by means of paleomagnetic analyses performed on analogue models. Eleven models were designed aimed at reproducing various tectonic settings in thin-skinned tectonics. Our models analyze in particular those features reported in the literature as possible causes for peculiar rotational patterns in the outermost as well as in the more internal fronts. In all the models the sedimentary cover was reproduced by frictional low-cohesion materials (sand and glass micro-beads), which detached either on frictional or on viscous layers. These latter were reproduced in the models by silicone. The sand forming the models has been previously mixed with magnetite-dominated powder. Before deformation, the models were magnetized by means of two permanent magnets generating within each model a quasi-linear magnetic field of intensity variable between 20 and 100 mT. After deformation, the models were cut into closely spaced vertical sections and sampled by means of 1×1-cm Plexiglas cylinders at several locations along curved fronts. Care was taken to collect paleomagnetic samples only within virtually undeformed thrust sheets, avoiding zones affected by pervasive shear. Afterwards, the natural remanent magnetization of these samples was measured, and alternating field demagnetization was used to isolate the principal components. The characteristic components of magnetization isolated were used to estimate the vertical-axis rotations occurring during model deformation. We find that indenters pushing into deforming belts from behind form non-rotational curved outer fronts. The more internal fronts show oroclinal-type rotations of a smaller magnitude than that expected for a perfect orocline. Lateral symmetrical obstacles in the foreland colliding with forward propagating belts produce non-rotational outer curved fronts as well, whereas in between and inside the obstacles a perfect orocline forms

  4. The environmental Kuznets curve and sustainability: A panel data analysis

    Farhani, Sahbi; Mrizak, Sana; Chaibi, Anissa; Rault, Christophe

    2014-01-01

    In recent years, sustainability has represented one of the most important policy goals explored in the environmental Kuznets curve (EKC) literature. But related hypotheses, performance measures and results continue to present a challenge. The present paper contributes to this ongoing literature by studying two different EKC specifications for 10 Middle East and North African (MENA) countries over the period 1990–2010 using panel data methods. For the first specification, namely EKC, we show that there is an inverted U-shape relationship between environmental degradation and income; while for the second specification, namely modified EKC (MEKC), we show that there is an inverted U-shape relationship between sustainability and human development (HD). The relationships are shaped by other factors such as energy, trade, manufacture added value and the role of law. More interestingly, findings from the estimation show that EKC hypothesis, HD and sustainability are crucial to build effective environmental policies. - Highlights: • Environmental Kuznets curve (EKC) and modified EKC models are examined for 10 MENA countries. • We attempt to include energy, trade, human development and sustainability in our approach. • The inverted U-shape relationship is verified for two models. • Human development positively affects the pollution and sustainability level

  5. Radiologist and angiographic procedures. Absorbed radiation dose

    Tryhus, M.; Mettler, F.A. Jr.; Kelsey, C.

    1987-01-01

    The radiation dose absorbed by the angiographer during angiographic procedures is of vital importance to the radiologist. Nevertheless, most articles on the subject are incomplete, and few measure gonadal dose. In this study, three TLDs were used for each of the following sites: radiologist's eyes, thyroid, gonads with and without shielding apron, and hands. The average dose during carotid angiograms was 2.6, 4.1, 0.4, 4.7, and 7.1 mrads to the eyes, thyroid, gonads with and without .5 mm of lead shielding, and hands, respectively. Average dose during abdominal and peripheral vascular angiographic procedures was 5.2, 7.5, 1.2, 8.5, and 39.9 mrads to the eyes, thyroid, gonads with and without shielding, and hands, respectively. A literature review demonstrates a significant reduction in radiation dose to the angiographer after the advent of automated injectors. Our measured doses for carotid angiography are compatible with contemporary reported values. There was poor correlation with fluoroscopy time and measured dose to the angiographer

  6. Establishment and validation of a dose-effect curve for γ-rays by cytogenetic analysis

    Barquinero, Joan F.; Caballin, Maria Rosa; Barrios, Leonardo; Ribas, Montserrat; Miro, Rosa; Egozcue, Josep

    1995-01-01

    A dose-effect curve obtained by analysis of dicentric chromosomes after irradiation of peripheral blood samples, from one donor, at 11 different doses of γ-rays is presented. For the elaboration of this curve, more than 18,000 first division metaphases have been analyzed. The results fit very well to the linear-quadratic model. To validate the curve, samples from six individuals (three controls and three occupationally exposed persons) were irradiated at 2 Gy. The results obtained, when compared with the curve, showed that in all cases the 95% confidence interval included the 2 Gy dose, with estimated dose ranges from 1.82 to 2.19 Gy

  7. Curve-of-growth analysis of M-type giants. beta. and. beta. Peg

    Hanni, L.; Kipper, M.

    1975-01-01

    The curve-of-growth analysis is carried out with high-dispersion spectrograms of the region lambda lambda 5050--6150 for two M-type stars ..beta.. And (MOIII) and ..beta.. Peg (M2II-III) by using the newest oscillator strengths available. It has been found that the form of our empirical curve of growth is consistent with that of the theoretical curve by Wrubel. By making use of the data derived from the curve-of-growth analyses, atmospheric parameters such as THETA/sub ex/, rho/sub e/, ..nu../sub t/ and the abundances of the elements have been determined.

  8. Fourier techniques for an analysis of eclipsing binary light curves. Pt. 6b

    Demircan, O.

    1980-01-01

    This is a continuation of a previous paper which appeared in this journal (Demircan, 1980b) and aims at ascertaining some other relations between the integral transforms of the light curves of eclipsing binary systems. The appropriate use of these relations should facilitate the numerical computations for an analysis of eclipsing binary light curves by different Fourier techniques. (orig.)

  9. p-y-ẏ curves for dynamic analysis of offshore wind turbine monopile foundations

    Bayat, Mehdi; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    2016-01-01

    Highlights •A two-dimensional analysis of a monopile segment moving horizontally through saturated soil is analyzed. •A p−y−ẏ curve accounting for the rate of pile motion is proposed as an alternative to static p−y curves. •The stiffness and damping properties related to soil structure interaction...

  10. Parent involvement and science achievement: A latent growth curve analysis

    Johnson, Ursula Yvette

    This study examined science achievement growth across elementary and middle school and parent school involvement using the Early Childhood Longitudinal Study - Kindergarten Class of 1998--1999 (ECLS-K). The ECLS-K is a nationally representative kindergarten cohort of students from public and private schools who attended full-day or half-day kindergarten class in 1998--1999. The present study's sample (N = 8,070) was based on students that had a sampling weight available from the public-use data file. Students were assessed in science achievement at third, fifth, and eighth grades and parents of the students were surveyed at the same time points. Analyses using latent growth curve modeling with time invariant and varying covariates in an SEM framework revealed a positive relationship between science achievement and parent involvement at eighth grade. Furthermore, there were gender and racial/ethnic differences in parents' school involvement as a predictor of science achievement. Findings indicated that students with lower initial science achievement scores had a faster rate of growth across time. The achievement gap between low and high achievers in earth, space and life sciences lessened from elementary to middle school. Parents' involvement with school usually tapers off after elementary school, but due to parent school involvement being a significant predictor of eighth grade science achievement, later school involvement may need to be supported and better implemented in secondary schooling.

  11. Study on elastic-plastic deformation analysis using a cyclic stress-strain curve

    Igari, Toshihide; Setoguchi, Katsuya; Yamauchi, Masafumi

    1983-01-01

    This paper presents the results of the elastic-plastic deformation analysis using a cyclic stress-strain curve with an intention to apply this method for predicting the low-cycle fatigue life. Uniaxial plastic cycling tests were performed on 2 1/4Cr-1Mo steel to investigate the correspondence between the cyclic stress-strain curve and the hysteresis loop, and also to determine what mathematical model should be used for analysis of deformation at stress reversal. Furthermore, a cyclic in-plane bending test was performed on a flat plate to clarify the validity of the cyclic stress-strain curve-based theoretical analysis. The results obtained are as follows: (1) The cyclic stress-strain curve corresponds nearly to the ascending curve of hysteresis loop scaled by a factor of 1/2 for both stress and strain. Therefore, the cyclic stress-strain curve can be determined from the shape of hysteresis loop, for simplicity. (2) To perform the elastic-plastic deformation analysis using the cyclic stress-strain curve is both practical and effective for predicting the cyclic elastic-plastic deformation of structures at the stage of advanced cycles. And Masing model can serve as a suitable mathematical model for such a deformation analysis. (author)

  12. Functional principal component analysis of glomerular filtration rate curves after kidney transplant.

    Dong, Jianghu J; Wang, Liangliang; Gill, Jagbir; Cao, Jiguo

    2017-01-01

    This article is motivated by some longitudinal clinical data of kidney transplant recipients, where kidney function progression is recorded as the estimated glomerular filtration rates at multiple time points post kidney transplantation. We propose to use the functional principal component analysis method to explore the major source of variations of glomerular filtration rate curves. We find that the estimated functional principal component scores can be used to cluster glomerular filtration rate curves. Ordering functional principal component scores can detect abnormal glomerular filtration rate curves. Finally, functional principal component analysis can effectively estimate missing glomerular filtration rate values and predict future glomerular filtration rate values.

  13. Angiographic assessment of initial balloon angioplasty results.

    Gardiner, Geoffrey A; Sullivan, Kevin L; Halpern, Ethan J; Parker, Laurence; Beck, Margaret; Bonn, Joseph; Levin, David C

    2004-10-01

    To determine the influence of three factors involved in the angiographic assessment of balloon angioplasty-interobserver variability, operator bias, and the definition used to determine success-on the primary (technical) results of angioplasty in the peripheral arteries. Percent stenosis in 107 lesions in lower-extremity arteries was graded by three independent, experienced vascular radiologists ("observers") before and after balloon angioplasty and their estimates were compared with the initial interpretations reported by the physician performing the procedure ("operator") and an automated quantitative computer analysis. Observer variability was measured with use of intraclass correlation coefficients and SD. Differences among the operator, observers, and the computer were analyzed with use of the Wilcoxon signed-rank test and analysis of variance. For each evaluator, the results in this series of lesions were interpreted with three different definitions of success. Estimation of residual stenosis varied by an average range of 22.76% with an average SD of 8.99. The intraclass correlation coefficients averaged 0.59 for residual stenosis after angioplasty for the three observers but decreased to 0.36 when the operator was included as the fourth evaluator. There was good to very good agreement among the three independent observers and the computer, but poor correlation with the operator (P definition of success was used. Significant differences among the operator, the three observers, and the computer were not present when the definition of success was based on less than 50% residual stenosis. Observer variability and bias in the subjective evaluation of peripheral angioplasty can have a significant influence on the reported initial success rates. This effect can be largely eliminated with the use of residual stenosis of less than 50% to define success. Otherwise, meaningful evaluation of angioplasty results will require independent panels of evaluators or

  14. Multivariate analysis of diagnostic parameters derived from whole-kidney and parenchymal time-activity curves

    Bergmann, H.; Mostbeck, A.; Samal, M.; Nimmon, C.C.; Staudenherz, A.; Dudczak, R.

    2002-01-01

    Aim: In a previous work, we have confirmed earlier reports that time-activity curves of renal cortex provide additional useful diagnostic information. The aim of this experiment was to support the finding quantitatively using multiple regression. Materials and Methods: In a retrospective study, we have analyzed MAG3 renal data (90 kidneys in 57 children). Whole-kidney (WK) and parenchymal (PA) time-activity curves were extracted from 20 min pre-diuretic phase using standard WK and parenchymal fuzzy ROIs. Using multiple regression analysis, peak time, mean transit time, output efficiency, and four additional indices of residual activity in WK and PA ROIs were related to the maximum elimination rate (EM) of urine after the diuretic. The kidneys were divided into four groups according to the WK peak time (WKPT): WKPT longer than 0 (all kidneys), 5, 10, and 15 min. Results: Multiple correlation coefficients between the set of WK, PA, and WK+PA curve parameters (independent variables) and the log EM (dependent variable) for each group are summarized. Conclusions: Using pre-diuretic time-activity curves, it is possible to predict diuretic response. This can be useful when interpreting dubious results. Parenchymal curves predict diuretic response better than the whole-kidney curves. With increasing WKPT the whole-kidney curves become useless, while the parenchymal curves are still useful. Using both WK and PA curves produces the best results. This demonstrates that both WK and PA curves carry independent diagnostic information. The contribution obtained from the parenchymal curves certainly worth the difficulties and time required to draw additional ROIs. However, substantial efforts have to be given to the accurate and reproducible definition of parenchymal ROIs

  15. A simple digital subtraction angiographic instrument

    Ando, Hiroshi; Kobayashi, Tsuyoshi; Imai, Yutaka; Yanagishita, Akira

    1983-01-01

    A digital subtraction angiographic instrument was manufactured using a conventional x-ray TV for gastrointestinal series and a computer for processing of nuclear medical data. The results of visualization of the aorta and its primary branches were reviewed with demonstrable cases. (Chiba, N.)

  16. Exposure doses to angiographers during interventional angiography

    Fukutomi, Yukimi; Yasuhara, Yoshifumi; Sugata, Shigenori; Fujii, Takashi; Kawakami, Toshiaki; Ikezoe, Junpei

    1997-01-01

    We report the exposure doses to angiographers during interventional angiography and the protective efficacy of protective aprons against X-rays in this study. The first (main) angiographer was exposed to the maximum dose of 1 μSv/min at the left chest area and lower abdominal area inside the protective apron. The second (assistant) angiographer was exposed to the maximum dose of 2 μSv/min at the left chest area and 1 μSv/min at the lower abdominal area. X-ray transmission ratio of the protective apron was 4.9 percent or less for UL25L, O percent for 0.35 mmPb and 4.3 percent or less for 0.5 mmPb. These results were lower than the dose equivalent limit based on the laws and ordinances. The protection capacities of these protective aprons proved to be sufficient. The exposure dose at the left extremity area outside the protective apron, however, was 24 times higher than at the left chest area inside. The data showed that it was not protected from scattered X-rays outside the protective apron. It is imperative to consider secondary protective material for the area outside the protective apron. Considering the risk of radiation, we need to better control exposure to angiographers. (author)

  17. Essentials of diagnostic and interventional angiographic technique

    Gerlock, A.J.; Mirfakhraee, M.

    1985-01-01

    This volume presents coverage of basic angiographic techniques and shows how to get to the point of taking the angiogram, and tells how to avoid pitfalls. Particularly valuable is the information on how to get out of trouble if an error is made while manipulating the catheter

  18. Angiographic diagnosis of the carotid artery pseudoaneurysm

    Qi Yueyong; Zou Liguang; Dai Shuhua; Tan Yinghui; Li Zhongyu; Zhou Zheng

    2004-01-01

    Objective: To create a further understanding of the angiographic features of the carotid artery pseudoaneurysm (CAPA) and to explore the clinical diagnostic value of angiography. Methods: Sixteen cases of CAPA with clinical and angiographic data were analyzed retrospectively. The angiographic appearances in all of the patients were observed dynamically and precisely with a double blind method by two experienced radiologists together and formed a consensus interpretation. Results: Angiography provided a definite diagnosis for all cases. The parent arteries included the common carotid artery (1 case), common carotid artery bifurcation (9 cases), internal carotid artery (5 cases) and external carotid artery (1 case). The angiographic features of the CAPA were: All cases showed the contrast media retension in the aneurysms; turbulent flow within aneurysm in 9 cases; the 'jetting sign' at the leak of the parent artery in 7 cases; increase angulation of the bifurcation of internal and external carotid arteries in 12 cases. Conclusions: Angiography is the most valuable examination method in diagnosis of CAPA, and it can not only provide definite diagnosis, but also play an important role in selection of therapeutic plan. (authors)

  19. Evaluation of PCR and high-resolution melt curve analysis for differentiation of Salmonella isolates.

    Saeidabadi, Mohammad Sadegh; Nili, Hassan; Dadras, Habibollah; Sharifiyazdi, Hassan; Connolly, Joanne; Valcanis, Mary; Raidal, Shane; Ghorashi, Seyed Ali

    2017-06-01

    Consumption of poultry products contaminated with Salmonella is one of the major causes of foodborne diseases worldwide and therefore detection and differentiation of Salmonella spp. in poultry is important. In this study, oligonucleotide primers were designed from hemD gene and a PCR followed by high-resolution melt (HRM) curve analysis was developed for rapid differentiation of Salmonella isolates. Amplicons of 228 bp were generated from 16 different Salmonella reference strains and from 65 clinical field isolates mainly from poultry farms. HRM curve analysis of the amplicons differentiated Salmonella isolates and analysis of the nucleotide sequence of the amplicons from selected isolates revealed that each melting curve profile was related to a unique DNA sequence. The relationship between reference strains and tested specimens was also evaluated using a mathematical model without visual interpretation of HRM curves. In addition, the potential of the PCR-HRM curve analysis was evaluated for genotyping of additional Salmonella isolates from different avian species. The findings indicate that PCR followed by HRM curve analysis provides a rapid and robust technique for genotyping of Salmonella isolates to determine the serovar/serotype.

  20. Analysis and Design of Stimulus Response Curves of E. coli

    Andreas Kremling

    2012-11-01

    Full Text Available Metabolism and signalling are tightly coupled in bacteria. Combining several theoretical approaches, a core model is presented that describes transcriptional and allosteric control of glycolysis in Escherichia coli. Experimental data based on microarrays, signalling components and extracellular metabolites are used to estimate kinetic parameters. A newly designed strain was used that adjusts the incoming glucose flux into the system and allows a kinetic analysis. Based on the results, prediction for intracelluar metabolite concentrations over a broad range of the growth rate could be performed and compared with data from literature.

  1. A method of non-destructive quantitative analysis of the ancient ceramics with curved surface

    He Wenquan; Xiong Yingfei

    2002-01-01

    Generally the surface of the sample should be smooth and flat in XRF analysis, but the ancient ceramics and hardly match this condition. Two simple methods are put forward in fundamental method and empirical correction method of XRF analysis, so the analysis of little sample or the sample with curved surface can be easily completed

  2. Time Alignment as a Necessary Step in the Analysis of Sleep Probabilistic Curves

    Rošt'áková, Zuzana; Rosipal, Roman

    2018-02-01

    Sleep can be characterised as a dynamic process that has a finite set of sleep stages during the night. The standard Rechtschaffen and Kales sleep model produces discrete representation of sleep and does not take into account its dynamic structure. In contrast, the continuous sleep representation provided by the probabilistic sleep model accounts for the dynamics of the sleep process. However, analysis of the sleep probabilistic curves is problematic when time misalignment is present. In this study, we highlight the necessity of curve synchronisation before further analysis. Original and in time aligned sleep probabilistic curves were transformed into a finite dimensional vector space, and their ability to predict subjects' age or daily measures is evaluated. We conclude that curve alignment significantly improves the prediction of the daily measures, especially in the case of the S2-related sleep states or slow wave sleep.

  3. Product differentiation by analysis of DNA melting curves during the polymerase chain reaction.

    Ririe, K M; Rasmussen, R P; Wittwer, C T

    1997-02-15

    A microvolume fluorometer integrated with a thermal cycler was used to acquire DNA melting curves during polymerase chain reaction by fluorescence monitoring of the double-stranded DNA specific dye SYBR Green I. Plotting fluorescence as a function of temperature as the thermal cycler heats through the dissociation temperature of the product gives a DNA melting curve. The shape and position of this DNA melting curve are functions of the GC/AT ratio, length, and sequence and can be used to differentiate amplification products separated by less than 2 degrees C in melting temperature. Desired products can be distinguished from undesirable products, in many cases eliminating the need for gel electrophoresis. Analysis of melting curves can extend the dynamic range of initial template quantification when amplification is monitored with double-stranded DNA specific dyes. Complete amplification and analysis of products can be performed in less than 15 min.

  4. Methodology of demand forecast by market analysis of electric power and load curves

    Barreiro, C.J.; Atmann, J.L.

    1989-01-01

    A methodology for demand forecast of consumer classes and their aggregation is presented. An analysis of the actual attended market can be done by appropriate measures and load curves studies. The suppositions for the future market behaviour by consumer classes (industrial, residential, commercial, others) are shown, and the actions for optimise this market are foreseen, obtained by load curves modulations. The process of future demand determination is obtained by the appropriate aggregation of this segmented demands. (C.G.C.)

  5. TYPE Ia SUPERNOVA LIGHT-CURVE INFERENCE: HIERARCHICAL BAYESIAN ANALYSIS IN THE NEAR-INFRARED

    Mandel, Kaisey S.; Friedman, Andrew S.; Kirshner, Robert P.; Wood-Vasey, W. Michael

    2009-01-01

    We present a comprehensive statistical analysis of the properties of Type Ia supernova (SN Ia) light curves in the near-infrared using recent data from Peters Automated InfraRed Imaging TELescope and the literature. We construct a hierarchical Bayesian framework, incorporating several uncertainties including photometric error, peculiar velocities, dust extinction, and intrinsic variations, for principled and coherent statistical inference. SN Ia light-curve inferences are drawn from the global posterior probability of parameters describing both individual supernovae and the population conditioned on the entire SN Ia NIR data set. The logical structure of the hierarchical model is represented by a directed acyclic graph. Fully Bayesian analysis of the model and data is enabled by an efficient Markov Chain Monte Carlo algorithm exploiting the conditional probabilistic structure using Gibbs sampling. We apply this framework to the JHK s SN Ia light-curve data. A new light-curve model captures the observed J-band light-curve shape variations. The marginal intrinsic variances in peak absolute magnitudes are σ(M J ) = 0.17 ± 0.03, σ(M H ) = 0.11 ± 0.03, and σ(M Ks ) = 0.19 ± 0.04. We describe the first quantitative evidence for correlations between the NIR absolute magnitudes and J-band light-curve shapes, and demonstrate their utility for distance estimation. The average residual in the Hubble diagram for the training set SNe at cz > 2000kms -1 is 0.10 mag. The new application of bootstrap cross-validation to SN Ia light-curve inference tests the sensitivity of the statistical model fit to the finite sample and estimates the prediction error at 0.15 mag. These results demonstrate that SN Ia NIR light curves are as effective as corrected optical light curves, and, because they are less vulnerable to dust absorption, they have great potential as precise and accurate cosmological distance indicators.

  6. Relationship between Angiographic Results and Morphology in Sidewall Intracranial Aneurysms after Stent-Assisted Coil Embolization.

    Nii, Kouhei; Aikawa, Hiroshi; Tsutsumi, Masanori; Eto, Ayumu; Iko, Minoru; Sakamoto, Kimiya; Inoue, Ritsuro; Mitsutake, Takafumi; Hanada, Hayatsura; Kazekawa, Kiyoshi

    2016-03-01

    Stent-assisted coil embolization (SACE) is used to address wide-necked or complex aneurysms. However, as they may recanalize after SACE, predictors of recanalization are needed. We investigated the relationship between follow-up angiographic results and the morphology of sidewall (SW) aneurysms in patients treated by SACE. Between September 2010 and September 2014, we performed 80 SACE procedures for SW intracranial aneurysms. Angiographic findings, obtained immediately after the procedure, 3-6 months thereafter, and when aneurysmal recanalization was suspected on MR angiogram scan, were recorded. Morphologically, the SW aneurysms were classified as "outside" (OS) and "partially inside" (PI) based on the curve of the axes of the proximal or distal parent artery with respect to the aneurysmal neck. Follow-up angiographic studies on OS- and PI SW aneurysms were compared. On the initial angiograms, we classified 42 aneurysms as OS and 38 as PI. Immediately after SACE, there was no significant difference in the angiographic findings on OS and PI aneurysms. However, on follow-up angiograms, there was a significant difference in the rate of spontaneous improvement (4 of 42 [OS] versus 21 of 38 [PI], P = .001). We performed additional coil embolization to treat 3 recanalized OS aneurysms. SW aneurysms classified morphologically as PI tended to occlude progressively even after incomplete occlusion by SACE. In contrast, aneurysms classified as OS must be observed carefully after SACE. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  7. Fitness analysis method for magnesium in drinking water with atomic absorption using quadratic curve calibration

    Esteban Pérez-López

    2014-11-01

    Full Text Available Because of the importance of quantitative chemical analysis in research, quality control, sales of services and other areas of interest , and the limiting of some instrumental analysis methods for quantification with linear calibration curve, sometimes because the short linear dynamic ranges of the analyte, and sometimes by limiting the technique itself, is that there is a need to investigate a little more about the convenience of using quadratic curves for analytical quantification, which seeks demonstrate that it is a valid calculation model for chemical analysis instruments. To this was taken as an analysis method based on the technique and atomic absorption spectroscopy in particular a determination of magnesium in a sample of drinking water Tacares sector Northern Grecia, employing a nonlinear calibration curve and a curve specific quadratic behavior, which was compared with the test results obtained for the same analysis with a linear calibration curve. The results show that the methodology is valid for the determination referred to, with all confidence, since the concentrations are very similar, and as used hypothesis testing can be considered equal.

  8. Characterization of Type Ia Supernova Light Curves Using Principal Component Analysis of Sparse Functional Data

    He, Shiyuan; Wang, Lifan; Huang, Jianhua Z.

    2018-04-01

    With growing data from ongoing and future supernova surveys, it is possible to empirically quantify the shapes of SNIa light curves in more detail, and to quantitatively relate the shape parameters with the intrinsic properties of SNIa. Building such relationships is critical in controlling systematic errors associated with supernova cosmology. Based on a collection of well-observed SNIa samples accumulated in the past years, we construct an empirical SNIa light curve model using a statistical method called the functional principal component analysis (FPCA) for sparse and irregularly sampled functional data. Using this method, the entire light curve of an SNIa is represented by a linear combination of principal component functions, and the SNIa is represented by a few numbers called “principal component scores.” These scores are used to establish relations between light curve shapes and physical quantities such as intrinsic color, interstellar dust reddening, spectral line strength, and spectral classes. These relations allow for descriptions of some critical physical quantities based purely on light curve shape parameters. Our study shows that some important spectral feature information is being encoded in the broad band light curves; for instance, we find that the light curve shapes are correlated with the velocity and velocity gradient of the Si II λ6355 line. This is important for supernova surveys (e.g., LSST and WFIRST). Moreover, the FPCA light curve model is used to construct the entire light curve shape, which in turn is used in a functional linear form to adjust intrinsic luminosity when fitting distance models.

  9. Angiographic picture of soft tissue desmoid fibromas

    Nikitaev, N.S.; Kuznetsova, M.A.

    1987-01-01

    Arteriography was performed in 35 patients with soft tissue desmoid fibromas. Angiographic semiotics of this disease was described. The frequency of detectability of symptoms in the arterial, parenchymatous and venous phases was analyzed. A tumor in the arterial phase was shown to be of normevascular or moderately hypervascular type without noticeable winding of the nutrient arteries, such features of malignancy as lacunae and ''tumor'' vessels being absent. In the parenchymatous phase desmoid tumors were shown to accumulate moderately a contrast substance, a tumor contour at a vast length was ill defined and poorly marked from surrounding tissues. The venous phase was less noticeable and the time of its appearance was usually within normal. In general by most of its parameters the angiographic picture of agressive fibromatosis corresponded to that of benign tumors and could be used for differential diagnosis of desmoid fibromas and some types of tissue sarcomas

  10. Angiographic diagnosis and treatment of gastrointestinal bleeding

    Park, Jae Hyung; Sung, Kyu Bo; Koo, Kyung Hoi; Bae, Tae Young; Chung, Eun Chul; Han, Man Chung

    1986-01-01

    Diagnostic angiographic evaluations were done in 33 patients with gastrointestinal bleeding for recent 5 years at Department of Radiology, Seoul National University Hospital. On 11 patients of them, therapeutic interventional procedures were made and the results were analysed. 1. In a total of 33 cases, there were 18 cases of upper GI bleeding and 15 cases of lower GI bleeding. The most frequent causes were peptic ulcer in the former and intestinal typhoid fever in the latter. 2. Bleeding sites were localized angiographically in 28 cases, so the detection rate was 85%. Four of the five angiographically negative cases were lower GI bleeding cases. 3. The most frequent bleeding site was left gastric artery (7/33). The next was ileocecal branch of superior mesenteric artery (6/33). 4. Among the 11 interventional procedures, Gelfoam embolization was done in 7 cases and Vasopressin infusion was tried in 4 cases. They were successful in 4 and 3 cases, suggesting 57% and 47% success rates respectively.

  11. Angiographic diagnosis and treatment of gastrointestinal bleeding

    Park, Jae Hyung; Sung, Kyu Bo; Koo, Kyung Hoi; Bae, Tae Young; Chung, Eun Chul; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1986-02-15

    Diagnostic angiographic evaluations were done in 33 patients with gastrointestinal bleeding for recent 5 years at Department of Radiology, Seoul National University Hospital. On 11 patients of them, therapeutic interventional procedures were made and the results were analysed. 1. In a total of 33 cases, there were 18 cases of upper GI bleeding and 15 cases of lower GI bleeding. The most frequent causes were peptic ulcer in the former and intestinal typhoid fever in the latter. 2. Bleeding sites were localized angiographically in 28 cases, so the detection rate was 85%. Four of the five angiographically negative cases were lower GI bleeding cases. 3. The most frequent bleeding site was left gastric artery (7/33). The next was ileocecal branch of superior mesenteric artery (6/33). 4. Among the 11 interventional procedures, Gelfoam embolization was done in 7 cases and Vasopressin infusion was tried in 4 cases. They were successful in 4 and 3 cases, suggesting 57% and 47% success rates respectively.

  12. AtomicJ: An open source software for analysis of force curves

    Hermanowicz, Paweł; Sarna, Michał; Burda, Kvetoslava; Gabryś, Halina

    2014-06-01

    We present an open source Java application for analysis of force curves and images recorded with the Atomic Force Microscope. AtomicJ supports a wide range of contact mechanics models and implements procedures that reduce the influence of deviations from the contact model. It generates maps of mechanical properties, including maps of Young's modulus, adhesion force, and sample height. It can also calculate stacks, which reveal how sample's response to deformation changes with indentation depth. AtomicJ analyzes force curves concurrently on multiple threads, which allows for high speed of analysis. It runs on all popular operating systems, including Windows, Linux, and Macintosh.

  13. AtomicJ: An open source software for analysis of force curves

    Hermanowicz, Paweł; Gabryś, Halina; Sarna, Michał; Burda, Kvetoslava

    2014-01-01

    We present an open source Java application for analysis of force curves and images recorded with the Atomic Force Microscope. AtomicJ supports a wide range of contact mechanics models and implements procedures that reduce the influence of deviations from the contact model. It generates maps of mechanical properties, including maps of Young's modulus, adhesion force, and sample height. It can also calculate stacks, which reveal how sample's response to deformation changes with indentation depth. AtomicJ analyzes force curves concurrently on multiple threads, which allows for high speed of analysis. It runs on all popular operating systems, including Windows, Linux, and Macintosh

  14. Retrospective North American CFL Experience Curve Analysis and Correlation to Deployment Programs

    Smith, Sarah J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-07-01

    Retrospective experience curves are a useful tool for understanding historic technology development, and can contribute to investment program analysis and future cost estimation efforts. This work documents our development of an analysis approach for deriving retrospective experience curves with a variable learning rate, and its application to develop an experience curve for compact fluorescent lamps for the global and North American markets over the years 1990-2007. Uncertainties and assumptions involved in interpreting data for our experience curve development are discussed, including the processing and transformation of empirical data, the selection of system boundaries, and the identification of historical changes in the learning rate over the course of 15 years. In the results that follow, we find that that the learning rate has changed at least once from 1990-2007. We also explore if, and to what degree, public deployment programs may have contributed to an increased technology learning rate in North America. We observe correlations between the changes in the learning rate and the initiation of new policies, abrupt technological advances, including improvements to ballast technology, and economic and political events such as trade tariffs and electricity prices. Finally, we discuss how the findings of this work (1) support the use of segmented experience curves for retrospective and prospective analysis and (2) may imply that investments in technological research and development have contributed to a change in market adoption and penetration.

  15. TL glow curve analysis of UV, beta and gamma induced limestone collected from Amarnath holy cave

    Vikas Dubey

    2015-01-01

    Full Text Available The paper reports themoluminescence glow curve analysis of UV (ultraviolet, β (beta and γ (gamma induced limestone collected from Amarnath holy cave. The collected natural sample was characterized by X-ray diffraction (XRD technique and crystallite size calculated by Scherer's formula. Surface morphology and particle size was calculated by transmission electron microscopy (TEM study. Effect of annealing temperature on collected lime stone examined by TL glow curve study. The limestone was irradiated by UV radiation (254 nm source and the TL glow curve recorded for different UV exposure time. For beta irradiation Sr90 source was used and is shows intense peak at 256 °C with a shoulder peak at higher temperature range. For gamma radiation Co60 source and TL glow curve recorded for different doses of gamma. The kinetic parameters calculation was performed for different glow curve by computerized glow curve deconvolution (CGCD technique. The chemical composition of natural limestone was analyzed by energy dispersive X-ray spectroscopy (EDXS.

  16. A computerized glow curve analysis (GCA) method for WinREMS thermoluminescent dosimeter data using MATLAB

    Harvey, John A.; Rodrigues, Miesher L.; Kearfott, Kimberlee J.

    2011-01-01

    A computerized glow curve analysis (GCA) program for handling of thermoluminescence data originating from WinREMS is presented. The MATLAB program fits the glow peaks using the first-order kinetics model. Tested materials are LiF:Mg,Ti, CaF 2 :Dy, CaF 2 :Tm, CaF 2 :Mn, LiF:Mg,Cu,P, and CaSO 4 :Dy, with most having an average figure of merit (FOM) of 1.3% or less, with CaSO 4 :Dy 2.2% or less. Output is a list of fit parameters, peak areas, and graphs for each fit, evaluating each glow curve in 1.5 s or less. - Highlights: → Robust algorithm for performing thermoluminescent dosimeter glow curve analysis. → Written in MATLAB so readily implemented on variety of computers. → Usage of figure of merit demonstrated for six different materials.

  17. A retrospective analysis of compact fluorescent lamp experience curves and their correlations to deployment programs

    Smith, Sarah Josephine; Wei, Max; Sohn, Michael D.

    2016-01-01

    Experience curves are useful for understanding technology development and can aid in the design and analysis of market transformation programs. Here, we employ a novel approach to create experience curves, to examine both global and North American compact fluorescent lamp (CFL) data for the years 1990–2007. We move away from the prevailing method of fitting a single, constant, exponential curve to data and instead search for break points where changes in the learning rate may have occurred. Our analysis suggests a learning rate of approximately 21% for the period of 1990–1997, and 51% and 79% in global and North American datasets, respectively, after 1998. We use price data for this analysis; therefore our learning rates encompass developments beyond typical “learning by doing”, including supply chain impacts such as market competition. We examine correlations between North American learning rates and the initiation of new programs, abrupt technological advances, and economic and political events, and find an increased learning rate associated with design advancements and federal standards programs. Our findings support the use of segmented experience curves for retrospective and prospective technology analysis, and may imply that investments in technology programs have contributed to an increase of the CFL learning rate. - Highlights: • We develop a segmented regression technique to estimate historical CFL learning curves. • CFL experience curves do not have a constant learning rate. • CFLs exhibited a learning rate of approximately 21% from 1990 to 1997. • The CFL learning rate significantly increased after 1998. • Increased CFL learning rate is correlated to technology deployment programs.

  18. Numerical analysis of thermoluminescence glow curves; Analisis numerico de las cruvas de termoluminiscencia

    Gomez Ros, J M; Delgado, A

    1989-07-01

    This report presents a method for the numerical analysis of complex thermoluminescence glow curves resolving the individual glow peak components. The method employs first order kinetics analytical expressions and is based In a Marquart-Levenberg minimization procedure. A simplified version of this method for thermoluminescence dosimetry (TLD) is also described and specifically developed to operate whit Lithium Fluoride TLD-100. (Author). 36 refs.

  19. Computational Tools for Probing Interactions in Multiple Linear Regression, Multilevel Modeling, and Latent Curve Analysis

    Preacher, Kristopher J.; Curran, Patrick J.; Bauer, Daniel J.

    2006-01-01

    Simple slopes, regions of significance, and confidence bands are commonly used to evaluate interactions in multiple linear regression (MLR) models, and the use of these techniques has recently been extended to multilevel or hierarchical linear modeling (HLM) and latent curve analysis (LCA). However, conducting these tests and plotting the…

  20. Isogeometric analysis of free-form Timoshenko curved beams including the nonlinear effects of large deformations

    Hosseini, Seyed Farhad; Hashemian, Ali; Moetakef-Imani, Behnam; Hadidimoud, Saied

    2018-03-01

    In the present paper, the isogeometric analysis (IGA) of free-form planar curved beams is formulated based on the nonlinear Timoshenko beam theory to investigate the large deformation of beams with variable curvature. Based on the isoparametric concept, the shape functions of the field variables (displacement and rotation) in a finite element analysis are considered to be the same as the non-uniform rational basis spline (NURBS) basis functions defining the geometry. The validity of the presented formulation is tested in five case studies covering a wide range of engineering curved structures including from straight and constant curvature to variable curvature beams. The nonlinear deformation results obtained by the presented method are compared to well-established benchmark examples and also compared to the results of linear and nonlinear finite element analyses. As the nonlinear load-deflection behavior of Timoshenko beams is the main topic of this article, the results strongly show the applicability of the IGA method to the large deformation analysis of free-form curved beams. Finally, it is interesting to notice that, until very recently, the large deformations analysis of free-form Timoshenko curved beams has not been considered in IGA by researchers.

  1. Computer aided cooling curve analysis for Al-5Si and Al-11Si alloys ...

    The effect of grain refiner, modifier, and combination of grain refiner cum modifier was studied on Al-5Si and Al-11Si alloys using computer aided cooling curve analysis. For combined grain refinement and modification effect, Al-Ti-B-Sr single master alloy was developed that acted as both grain refiner and modifier.

  2. Light curve analysis of the late type binary V523 Cassiopeiae

    Latković O.

    2009-01-01

    Full Text Available We present the analysis of V and R light curves of the late type contact binary V523 Cas for the season of 2006. These observations make part of the monitoring program aimed at studying the long-term light curve variability in this system. Our results confirm that the system is in an over contact configuration, and include a bright spot in the neck region of the cooler and larger primary. We compare these results with the previous solution, obtained for the season 2005 dataset and discuss the differences.

  3. IMAGE-PLANE ANALYSIS OF n-POINT-MASS LENS CRITICAL CURVES AND CAUSTICS

    Danek, Kamil; Heyrovský, David, E-mail: kamil.danek@utf.mff.cuni.cz, E-mail: heyrovsky@utf.mff.cuni.cz [Institute of Theoretical Physics, Faculty of Mathematics and Physics, Charles University in Prague (Czech Republic)

    2015-06-10

    The interpretation of gravitational microlensing events caused by planetary systems or multiple stars is based on the n-point-mass lens model. The first planets detected by microlensing were well described by the two-point-mass model of a star with one planet. By the end of 2014, four events involving three-point-mass lenses had been announced. Two of the lenses were stars with two planetary companions each; two were binary stars with a planet orbiting one component. While the two-point-mass model is well understood, the same cannot be said for lenses with three or more components. Even the range of possible critical-curve topologies and caustic geometries of the three-point-mass lens remains unknown. In this paper we provide new tools for mapping the critical-curve topology and caustic cusp number in the parameter space of n-point-mass lenses. We perform our analysis in the image plane of the lens. We show that all contours of the Jacobian are critical curves of re-scaled versions of the lens configuration. Utilizing this property further, we introduce the cusp curve to identify cusp-image positions on all contours simultaneously. In order to track cusp-number changes in caustic metamorphoses, we define the morph curve, which pinpoints the positions of metamorphosis-point images along the cusp curve. We demonstrate the usage of both curves on simple two- and three-point-mass lens examples. For the three simplest caustic metamorphoses we illustrate the local structure of the image and source planes.

  4. Quantitative analysis of the dual-energy CT virtual spectral curve for focal liver lesions characterization

    Wang, Qi, E-mail: wq20@hotmail.com; Shi, Gaofeng, E-mail: gaofengs62@sina.com; Qi, Xiaohui, E-mail: qixiaohui1984@163.com; Fan, Xueli, E-mail: 407849960@qq.com; Wang, Lijia, E-mail: 893197597@qq.com

    2014-10-15

    Highlights: • We establish a feasible method using the virtual spectral curves (VSC) to differentiate focal liver lesions using DECT. • Our study shows the slope of the VSC can be used to differentiate between hemangioma, HCC, metastasis and cyst. • Importantly, the diagnostic specificities associated with using the slope to diagnose both hemangioma and cysts were 100%. - Abstract: Objective: To assess the usefulness of the spectral curve slope of dual-energy CT (DECT) for differentiating between hepatocellular carcinoma (HCC), hepatic metastasis, hemangioma (HH) and cysts. Methods: In total, 121 patients were imaged in the portal venous phase using dual-energy mode. Of these patients, 23 patients had HH, 28 patients had HCC, 40 patients had metastases and 30 patients had simple cysts. The spectral curves of the hepatic lesions were derived from the 40–190 keV levels of virtual monochromatic spectral imaging. The spectral curve slopes were calculated from 40 to 110 keV. The slopes were compared using the Kruskal–Wallis test. Receiver operating characteristic curves (ROC) were used to determine the optimal cut-off value of the slope of the spectral curve to differentiate between the lesions. Results: The spectral curves of the four lesion types had different baseline levels. The HH baseline level was the highest followed by HCC, metastases and cysts. The slopes of the spectral curves of HH, HCC, metastases and cysts were 3.81 ± 1.19, 1.49 ± 0.57, 1.06 ± 0.76 and 0.13 ± 0.17, respectively. These values were significantly different (P < 0.008). Based on ROC analysis, the respective diagnostic sensitivity and specificity were 87% and 100% for hemangioma (cut-off value ≥ 2.988), 82.1% and 65.9% for HCC (cut-off value 1.167–2.998), 65.9% and 59% for metastasis (cut-off value 0.133–1.167) and 44.4% and 100% for cysts (cut-off value ≤ 0.133). Conclusion: Quantitative analysis of the DECT spectral curve in the portal venous phase can be used to

  5. Analysis of the nonlinear dynamics of a 2-axle freight wagon in curves

    Di Gialleonardo, Egidio; Bruni, Stefano; True, Hans

    2014-01-01

    This paper deals with the study of the nonlinear dynamic behaviour of 2-axle freight wagons in curves, considering the case of one single wagon (neglecting inter-car coupling forces) and of multiple wagons interacting through the buffers and the couplers. A multi-body model of a single wagon...... and of a three-car assembly is introduced, paying particular attention to the nonlinear and nonsmooth modelling of the suspensions and of the inter-car coupling elements. Using this model, a numerical analysis of the steady-state solution reached after the negotiation of curve transition is presented......, it is shown that the coupling forces exchanged by the wagons significantly affect their dynamics in a curve, reducing the amplitude of vibration....

  6. Analysis of the radial distribution curves of partially ordered condensed carbon films

    Palatnik, L.S.; Derevyanchenko, A.S.; Nechitajlo, A.A.; Stetsenko, A.N.; Gorbenko, N.I.

    1977-01-01

    The Fourier analysis of the electron scattering curves has been carried out to determine the short-range order structure of carbon condensates. The intensity curves for carbon films condensed in a approximately 10 -6 Torr vacuum upon a substrate heated up to 600 deg C were obtained by diffraction techniques with filtration of the inelastic scattered electron background. The radial distribution curve errors were analyzed and quantified with the aid of a computer to determine the short-range order of the condensed carbon. It has been shown that carbon films consist of regions measuring approximately 20 A formed by parallelly packed graphite nets with azimuthal orientation different from that in ideal graphite crystals

  7. A semi-analytical three-dimensional free vibration analysis of functionally graded curved panels

    Zahedinejad, P. [Department of Mechanical Engineering, Islamic Azad University, Branch of Shiraz, Shiraz (Iran, Islamic Republic of); Malekzadeh, P., E-mail: malekzadeh@pgu.ac.i [Department of Mechanical Engineering, Persian Gulf University, Persian Gulf University Boulevard, Bushehr 75168 (Iran, Islamic Republic of); Center of Excellence for Computational Mechanics, Shiraz University, Shiraz (Iran, Islamic Republic of); Farid, M. [Department of Mechanical Engineering, Islamic Azad University, Branch of Shiraz, Shiraz (Iran, Islamic Republic of); Karami, G. [Department of Mechanical Engineering and Applied Mechanics, North Dakota State University, Fargo, ND 58105-5285 (United States)

    2010-08-15

    Based on the three-dimensional elasticity theory, free vibration analysis of functionally graded (FG) curved thick panels under various boundary conditions is studied. Panel with two opposite edges simply supported and arbitrary boundary conditions at the other edges are considered. Two different models of material properties variations based on the power law distribution in terms of the volume fractions of the constituents and the exponential distribution of the material properties through the thickness are considered. Differential quadrature method in conjunction with the trigonometric functions is used to discretize the governing equations. With a continuous material properties variation assumption through the thickness of the curved panel, differential quadrature method is efficiently used to discretize the governing equations and to implement the related boundary conditions at the top and bottom surfaces of the curved panel and in strong form. The convergence of the method is demonstrated and to validate the results, comparisons are made with the solutions for isotropic and FG curved panels. By examining the results of thick FG curved panels for various geometrical and material parameters and subjected to different boundary conditions, the influence of these parameters and in particular, those due to functionally graded material parameters are studied.

  8. Study on characteristic points of boiling curve by using wavelet analysis and genetic algorithm

    Wei Huiming; Su Guanghui; Qiu Suizheng; Yang Xingbo

    2009-01-01

    Based on the wavelet analysis theory of signal singularity detection,the critical heat flux (CHF) and minimum film boiling starting point (q min ) of boiling curves can be detected and analyzed by using the wavelet multi-resolution analysis. To predict the CHF in engineering, empirical relations were obtained based on genetic algorithm. The results of wavelet detection and genetic algorithm prediction are consistent with experimental data very well. (authors)

  9. Acquirement of true stress-strain curve using true fracture strain obtained by tensile test and FE analysis

    Lee, Kyoung Yoon; Kim, Tae Hyung; Lee, Hyung Yil

    2009-01-01

    In this work, we predict a true fracture strain using load-displacement curves from tensile test and Finite Element Analysis (FEA), and suggest a method for acquiring true Stress-Strain (SS) curves by predicted fracture strain. We first derived the true SS curve up to necking point from load-displacement curve. As the beginning, the posterior necking part of true SS curve is linearly extrapolated with the slope at necking point. The whole SS curve is then adopted for FE simulation of tensile test. The Bridgman factor or suitable plate correction factors are applied to pre and post FEA. In the load-true strain curve from FEA, the true fracture strain is determined as the matching point to test fracture load. The determined true strain is validated by comparing with test fracture strain. Finally, we complete the true SS curve by combining the prior necking part and linear part, the latter of which connects necking and predicted fracture points.

  10. Acquirement of true stress-strain curve using true fracture strain obtained by tensile test and FE analysis

    Lee, Kyoung Yoon; Kim, Tae Hyung; Lee, Hyung Yil [Sogang University, Seoul (Korea, Republic of)

    2009-07-01

    In this work, we predict a true fracture strain using load-displacement curves from tensile test and Finite Element Analysis (FEA), and suggest a method for acquiring true Stress-Strain (SS) curves by predicted fracture strain. We first derived the true SS curve up to necking point from load-displacement curve. As the beginning, the posterior necking part of true SS curve is linearly extrapolated with the slope at necking point. The whole SS curve is then adopted for FE simulation of tensile test. The Bridgman factor or suitable plate correction factors are applied to pre and post FEA. In the load-true strain curve from FEA, the true fracture strain is determined as the matching point to test fracture load. The determined true strain is validated by comparing with test fracture strain. Finally, we complete the true SS curve by combining the prior necking part and linear part, the latter of which connects necking and predicted fracture points.

  11. Acquirement of True Stress-strain Curve Using True Fracture Strain Obtained by Tensile Test and FE Analysis

    Lee, Kyoung Yoon; Lee, Hyung Yil [Sogang University, Seoul (Korea, Republic of); Kim, Tae Hyung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-10-15

    In this work, we predict a true fracture strain using load-displacement curves from tensile test and finite element analysis (FEA), and suggest a method for acquiring true stress-strain (SS) curves by predicted fracture strain. We first derived the true SS curve up to necking point from load-displacement curve. As the beginning, the posterior necking part of true SS curve is linearly extrapolated with the slope at necking point. The whole SS curve is then adopted for FE simulation of tensile test. The Bridgman factor or suitable plate correction factors are applied to pre and post FEA. In the load-true strain curve from FEA, the true fracture strain is determined as the matching point to test fracture load. The determined true strain is validated by comparing with test fracture strain. Finally, we complete the true SS curve by combining the prior necking part and linear part, the latter of which connects necking and predicted fracture points.

  12. CT, MR and angiographic findings of hemangiopericytomas

    Lim, Soo Mee; Lee, Ho Kyu; Shin, Ji Hoon; Kim, Jae Kyun; Kim, Dae Hong; Choi, Choong Gon; Suh, Dae Chul

    1999-01-01

    Hemangiopericytoma(HP) exhibits its pathologic findings different from those of meningioma or other angiomatous tumor; and its clinical behavior is unique and prognosis worse than other cases. We reviewed the CT, MR and angiographic findings of HPs and evaluated differential radiologic points of comparison between typical meningiomas and meningeal HPs. MR(n=16), CT(n=5) and angiographic imaging(n=10) were performed in 18 patients(M:F = 12:6, mean age: 45 years) with histologically proven primary HPs. We evaluated the imaging findings of HPs with respect to site, shape, size, signal intensity, enhancement characteristics, vascular signal voids, calcification, bony and adjacent sinus involvement, and angiographic findings. HPs were meningeal in 14 cases and nonmeningeal in four. Meningeal HPs were located in the parasagittal region(n=8), convexity(n=3), intradural extramedullary space(n=1), choroid plexus(n=1), and olfactory groove(n=1). Nonmeningeal HPs were located in the masticator space(n=2), paraspinal area(n=1) and supraclavicular area(n=1). The mean maximal dimension of tumors was about 5.4cm and their shape was papillary(n=8) or lobulated(n=7). MR images showed high(n=13) or iso(n=3) signal intensities on T2W1, and heterogeneity on T2W1(n=9). Vascular signal voids in the mass were seen in all cases, while in two cases, CT scanning showed nodular dense calcification. Bone destruction was present in six cases, but no hyperostosis was found. In five cases, the superior sagittal sinus was involved. Angiographic images revealed highly vascular masses supplied by the internal carotid artery(n=5), external carotid artery(n=8), descending scapular artery(n=1) and radiculomedullary artery(n=1), with delayed tumor blush during the capillary and venous phase in which there was no arteriovenous shunt. HP is one of the extra-axial tumors in which there is hypervascularity, aggressive bony destruction arising in the meningeal and extrameningeal area, and heterogeneous high

  13. Accessory left gastric artery: angiographic anatomy

    Lee, Kang Soo; Lim, Hyung Guhn; Kim, Hong Soo; Jeon, Doo Sung [Presbyterian Medical Center, Chunju (Korea, Republic of); Chung, Jin Wook; Park, Jae Hyung [College of Medicine and the Institute of Radiation Medicine, Seoul National University, Seoul (Korea, Republic of); Song, Soon Young [Myongji Hospital, College of Medicine, Kwandong University, Seoul (Korea, Republic of)

    2000-09-01

    To evaluate the angiographic anatomy of the accessory left gastric artery (accLGA). We evaluated the angiographic findings of the accLGA in 50 patients (Angiostar; Siemens, Erlangen, Germany). Performing celiac and selective angiography in 50 and 34 patients, respectively. By means of celiac angiography, (1) site of origin, (2) anatomical course, (3) diameter, (4) degree of tortuosity, and (5) distal tapering were evaluated, while selective angiography was used to determine (1) arterial branching, (2) area of blood supply, and (3) patterns of gastric wall stain. Celiac angiography showed that the accLGA arose from the left hepatic artery (LHA) in 45 cases (90%) and from the proper hepatic artery in five (10%). If the accLGA arose from the LHA, its origin entirely depended on the branching pattern of the latter. It always arose from the lateral branch of the LHA furthest to the left and uppermost, and proximal to its umbilical point. The most common anatomical course of the accLGA, seen in 27 cases (54%), was between the S2 and S3 segmental branch. The diameter and degree of tortuosity of the accLGA were similar to those of adjacent intrahepatic branches in 21 (42%) and 33 cases (66%), respectively. The degree of tapering was less than that of adjacent intrahepatic vessel in 28 (56%). Selective angiography demonstrated esophageal branching of the acc LGA in 27 cases (79%), inferior phrenic arterial branching in three (9%), a mediastinal branch in one (3%), and hypervascularity of the lung in one (3%). In 15 cases (44%), bifurcation of the accLGA was recognized. The vascular territory of the accLGA was the gastric fundus together with the distal esophagus in 21 cases (62%), mainly the gastric fundus in six (18%), and mainly the distal esophagus in four (12%). The pattern of gastric mucosal stain was curvilinear wall in 31 cases (91%) and nodular in three (9%). A knowledge of the angiographic anatomy of the accLGA facilitates accurate recognition of this artery on

  14. Relationship between the curve of Spee and craniofacial variables: A regression analysis.

    Halimi, Abdelali; Benyahia, Hicham; Azeroual, Mohamed-Faouzi; Bahije, Loubna; Zaoui, Fatima

    2018-06-01

    The aim of this regression analysis was to identify the determining factors, which impact the curve of Spee during its genesis, its therapeutic reconstruction, and its stability, within a continuously evolving craniofacial morphology throughout life. We selected a total of 107 patients, according to the inclusion criteria. A morphological and functional clinical examination was performed for each patient: plaster models, tracing of the curve of Spee, crowding, Angle's classification, overjet and overbite were thus recorded. Then, we made a cephalometric analysis based on the standardized lateral cephalograms. In the sagittal dimension, we measured the values of angles ANB, SNA, SNB, SND, I/i; and the following distances: AoBo, I/NA, i/NB, SE and SL. In the vertical dimension, we measured the values of angles FMA, GoGn/SN, the occlusal plane, and the following distances: SAr, ArD, Ar/Con, Con/Gn, GoPo, HFP, HFA and IF. The statistical analysis was performed using the SPSS software with a significance level of 0.05. Our sample including 107 subjects was composed of 77 female patients (71.3%) and 30 male patients (27.8%) 7 hypodivergent patients (6.5%), 56 hyperdivergent patients (52.3%) and 44 normodivergent patients (41.1%). Patients' mean age was 19.35±5.95 years. The hypodivergent patients presented more pronounced curves of Spee compared to the normodivergent and the hyperdivergent populations; patients in skeletal Class I presented less pronounced curves of Spee compared to patients in skeletal Class II and Class III. These differences were non significant (P>0.05). The curve of Spee was positively and moderately correlated with Angle's classification, overjet, overbite, sellion-articulare distance, and breathing type (P0.05). Seventy five percent (75%) of the hyperdivergent patients with an oral breathing presented an overbite of 3mm, which is quite excessive given the characteristics often admitted for this typology; this parameter could explain the overbite

  15. Analysis of the deconvolution of the thermoluminescent curve of the zirconium oxide doped with graphite

    Salas C, P.; Estrada G, R.; Gonzalez M, P.R.; Mendoza A, D.

    2003-01-01

    In this work, we present a mathematical analysis of the behavior of the thermoluminescent curve (Tl) induced by gamma radiation in samples made of zirconium oxide doped with different amounts of graphite. In accordance with the results gamma radiation induces a Tl curve with two maximum of emission localized in the temperatures at 139 and 250 C, the area under the curve is increasing as a function of the time of exposition to the radiation. The analysis of curve deconvolution, in accordance with the theory which indicates that this behavior must be obey a Boltzmann distribution, we found that each one of them has a different growth velocity as the time of exposition increase. In the same way, we observed that after the irradiation was suspended each one of the maximum decrease with different velocity. The behaviour observed in the samples is very interesting because the zirconium oxide has attracted the interest of many research groups, this material has demonstrated to have many applications in thermoluminescent dosimetry and it can be used in the quantification of radiation. (Author)

  16. Better P-curves: Making P-curve analysis more robust to errors, fraud, and ambitious P-hacking, a Reply to Ulrich and Miller (2015).

    Simonsohn, Uri; Simmons, Joseph P; Nelson, Leif D

    2015-12-01

    When studies examine true effects, they generate right-skewed p-curves, distributions of statistically significant results with more low (.01 s) than high (.04 s) p values. What else can cause a right-skewed p-curve? First, we consider the possibility that researchers report only the smallest significant p value (as conjectured by Ulrich & Miller, 2015), concluding that it is a very uncommon problem. We then consider more common problems, including (a) p-curvers selecting the wrong p values, (b) fake data, (c) honest errors, and (d) ambitiously p-hacked (beyond p < .05) results. We evaluate the impact of these common problems on the validity of p-curve analysis, and provide practical solutions that substantially increase its robustness. (c) 2015 APA, all rights reserved).

  17. Renal artery origins: best angiographic projection angles.

    Verschuyl, E J; Kaatee, R; Beek, F J; Patel, N H; Fontaine, A B; Daly, C P; Coldwell, D M; Bush, W H; Mali, W P

    1997-10-01

    To determine the best projection angles for imaging the renal artery origins in profile. A mathematical model of the anatomy at the renal artery origins in the transverse plane was used to analyze the amount of aortic lumen that projects over the renal artery origins at various projection angles. Computed tomographic (CT) angiographic data about the location of 400 renal artery origins in 200 patients were statistically analyzed. In patients with an abdominal aortic diameter no larger than 3.0 cm, approximately 0.5 mm of the proximal part of the renal artery and origin may be hidden from view if there is a projection error of +/-10 degrees from the ideal image. A combination of anteroposterior and 20 degrees and 40 degrees left anterior oblique projections resulted in a 92% yield of images that adequately profiled the renal artery origins. Right anterior oblique projections resulted in the least useful images. An error in projection angle of +/-10 degrees is acceptable for angiographic imaging of the renal artery origins. Patients sex, site of interest (left or right artery), and local diameter of the abdominal aorta are important factors to consider.

  18. Clinical application of digital angiographic system DIGITEX2400

    Kawai, Masumi; Tanaka, Shuji; Fujino, Yoshiyuki; Yasumi, Masayuki (Shimadzu Corp., Kyoto (Japan))

    1992-10-01

    Digital angiography (DA) has been of widespread use clinically, and it has attracted considerable attention in angiographic examination today. And under the condition of the spread of interventional angiography, not only high quality image but also ease of operation are required to the system. The clinical usefullness of digital angiographic system DIGITEX2400 are reported in this paper. (author).

  19. Clinical application of digital angiographic system DIGITEX2400

    Kawai, Masumi; Tanaka, Shuji; Fujino, Yoshiyuki; Yasumi, Masayuki

    1992-01-01

    Digital angiography (DA) has been of widespread use clinically, and it has attracted considerable attention in angiographic examination today. And under the condition of the spread of interventional angiography, not only high quality image but also ease of operation are required to the system. The clinical usefullness of digital angiographic system DIGITEX2400 are reported in this paper. (author)

  20. DETERMINATION ANALYSIS OF TEMPERATURE REGIMES, FUNCTIONAL CHARACTERISTICS AND SLIDING CURVES OF A HYDRODYNAMIC CLUTCH

    Božidar V Krstić

    2010-01-01

    Full Text Available Analysis of output quality of power transmitters is possible in position when characteristics are determined earlier. This is the reason why we focused on determination of these characteristics for a concrete power hydro-transmitter. This means that the investigation task primarily consisted of determination of functional characteristics, defining of the sliding curves and temperature regimes of a concrete hydrodynamic clutch. Results of velocity and pressure field investigations in the working space of this clutch, obtained by use of the same test setup, are the basis for determination and analysis of the functional characteristics, sliding curves and temperature regimes. In this work we also analyzed function of the hydrodynamic transmitter in assembly with an internal combustion engine, as well as a process of acceleration and deceleration of a vehicle with this assembly in it.

  1. Maximum likelihood fitting of FROC curves under an initial-detection-and-candidate-analysis model

    Edwards, Darrin C.; Kupinski, Matthew A.; Metz, Charles E.; Nishikawa, Robert M.

    2002-01-01

    We have developed a model for FROC curve fitting that relates the observer's FROC performance not to the ROC performance that would be obtained if the observer's responses were scored on a per image basis, but rather to a hypothesized ROC performance that the observer would obtain in the task of classifying a set of 'candidate detections' as positive or negative. We adopt the assumptions of the Bunch FROC model, namely that the observer's detections are all mutually independent, as well as assumptions qualitatively similar to, but different in nature from, those made by Chakraborty in his AFROC scoring methodology. Under the assumptions of our model, we show that the observer's FROC performance is a linearly scaled version of the candidate analysis ROC curve, where the scaling factors are just given by the FROC operating point coordinates for detecting initial candidates. Further, we show that the likelihood function of the model parameters given observational data takes on a simple form, and we develop a maximum likelihood method for fitting a FROC curve to this data. FROC and AFROC curves are produced for computer vision observer datasets and compared with the results of the AFROC scoring method. Although developed primarily with computer vision schemes in mind, we hope that the methodology presented here will prove worthy of further study in other applications as well

  2. Analysis of axisymmetric shells subjected to asymmetric loads using field consistent shear flexible curved element

    Balakrishna, C; Sarma, B S [Defence Research and Development Laboratory, Hyderabad (India)

    1989-02-01

    A formulation for axisymmetric shell analysis under asymmetric load based on Fourier series representation and using field consistent 3 noded curved axisymmetric shell element is presented. Different field inconsistent/consistent interpolations for an element based on shear flexible theory have been studied for thick and thin shells under asymmetric loads. Various examples covering axisymmetric as well as asymmetric loading cases have been analyzed and numerical results show a good agreement with the available results in the case of thin shells. 12 refs.

  3. Improving Accuracy and Temporal Resolution of Learning Curve Estimation for within- and across-Session Analysis

    Tabelow, Karsten; König, Reinhard; Polzehl, Jörg

    2016-01-01

    Estimation of learning curves is ubiquitously based on proportions of correct responses within moving trial windows. Thereby, it is tacitly assumed that learning performance is constant within the moving windows, which, however, is often not the case. In the present study we demonstrate that violations of this assumption lead to systematic errors in the analysis of learning curves, and we explored the dependency of these errors on window size, different statistical models, and learning phase. To reduce these errors in the analysis of single-subject data as well as on the population level, we propose adequate statistical methods for the estimation of learning curves and the construction of confidence intervals, trial by trial. Applied to data from an avoidance learning experiment with rodents, these methods revealed performance changes occurring at multiple time scales within and across training sessions which were otherwise obscured in the conventional analysis. Our work shows that the proper assessment of the behavioral dynamics of learning at high temporal resolution can shed new light on specific learning processes, and, thus, allows to refine existing learning concepts. It further disambiguates the interpretation of neurophysiological signal changes recorded during training in relation to learning. PMID:27303809

  4. Improving Accuracy and Temporal Resolution of Learning Curve Estimation for within- and across-Session Analysis.

    Matthias Deliano

    Full Text Available Estimation of learning curves is ubiquitously based on proportions of correct responses within moving trial windows. Thereby, it is tacitly assumed that learning performance is constant within the moving windows, which, however, is often not the case. In the present study we demonstrate that violations of this assumption lead to systematic errors in the analysis of learning curves, and we explored the dependency of these errors on window size, different statistical models, and learning phase. To reduce these errors in the analysis of single-subject data as well as on the population level, we propose adequate statistical methods for the estimation of learning curves and the construction of confidence intervals, trial by trial. Applied to data from an avoidance learning experiment with rodents, these methods revealed performance changes occurring at multiple time scales within and across training sessions which were otherwise obscured in the conventional analysis. Our work shows that the proper assessment of the behavioral dynamics of learning at high temporal resolution can shed new light on specific learning processes, and, thus, allows to refine existing learning concepts. It further disambiguates the interpretation of neurophysiological signal changes recorded during training in relation to learning.

  5. The Effect of Cilostazol on the Angiographic Outcome of Drug-Eluting Coronary Stents Angiographic Analysis of the CILON-T (Influence of CILostazol-Based Triple Antiplatelet Therapy ON Ischemi Complication after Drug-Eluting StenT Implantation) Trial.

    Suh, Jung-Won; Lee, Seung-Pyo; Park, KyungWoo; Kang, Hyun-Jae; Koo, Bon-Kwon; Cho, Young-Seok; Youn, Tae-Jin; Chae, In-Ho; Choi, Dong-Ju; Rha, Seung-Woon; Bae, Jang-Ho; Kwon, Taek-Geun; Bae, Jang-Whan; Cho, Myeong-Chan; Kim, Hyo-Soo

    2017-12-12

    It is not clear if anti-restonotic effect of cilostazol is consistent for different types of drug-eluting stents (DES).The purpose of this study was to compare the anti-proliferative effect of cilostazol between DAT and TAT with consideration of confounding influences of DES type.Nine hundred and fifteen patients were randomized to either dual antiplatelet therapy (DAT; aspirin and clopidogrel) or triple antiplatelet therapy (TAT; aspirin, clopidogrel, and cilostazol) in the previous CILON-T trial. After excluding 70 patients who received both or neither stents, we analyzed 845 patients who received exclusively PES or ZES, and compared in-stent late loss at 6 months between both antiplatelet regimens (DAT versus TAT).Baseline angiographic and clinical characteristics were similar between the DAT (656 lesions in 425 patients) and the TAT group (600 lesions in 420 patients). The 6-month follow-up angiography was completed in 745 patients (88.2%). Quantitative coronary angiography showed that TAT significantly reduced in-stent late loss (DAT 0.62 ± 0.62 mm versus TAT 0.54 ± 0.49 mm, P = 0.015). Stent type, diabetes or lesion length did not interact with difference of late loss. However, reduction of late loss by cilostazol did not lead to a significant reduction in the rate of target lesion revascularization (TLR) (DAT 7.8% versus TAT 6.9%, P = 0.69) due to a nonlinear relationship found between late loss and TLR.The TAT group showed less in-stent late loss as compared to the DAT group. This was consistently observed regardless of DES type, lesion length, or diabetic status. However, reduction of late loss by cilostazol did not lead to a significant reduction in TLR.

  6. The Use of Statistically Based Rolling Supply Curves for Electricity Market Analysis: A Preliminary Look

    Jenkin, Thomas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Larson, Andrew [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ruth, Mark F [National Renewable Energy Laboratory (NREL), Golden, CO (United States); King, Ben [U.S. Department of Energy; Spitsen, Paul [U.S. Department of Energy

    2018-03-27

    In light of the changing electricity resource mixes across the United States, an important question in electricity modeling is how additions and retirements of generation, including additions in variable renewable energy (VRE) generation could impact markets by changing hourly wholesale energy prices. Instead of using resource-intensive production cost models (PCMs) or building and using simple generator supply curves, this analysis uses a 'top-down' approach based on regression analysis of hourly historical energy and load data to estimate the impact of supply changes on wholesale electricity prices, provided the changes are not so substantial that they fundamentally alter the market and dispatch-order driven behavior of non-retiring units. The rolling supply curve (RSC) method used in this report estimates the shape of the supply curve that fits historical hourly price and load data for given time intervals, such as two-weeks, and then repeats this on a rolling basis through the year. These supply curves can then be modified on an hourly basis to reflect the impact of generation retirements or additions, including VRE and then reapplied to the same load data to estimate the change in hourly electricity price. The choice of duration over which these RSCs are estimated has a significant impact on goodness of fit. For example, in PJM in 2015, moving from fitting one curve per year to 26 rolling two-week supply curves improves the standard error of the regression from 16 dollars/MWh to 6 dollars/MWh and the R-squared of the estimate from 0.48 to 0.76. We illustrate the potential use and value of the RSC method by estimating wholesale price effects under various generator retirement and addition scenarios, and we discuss potential limits of the technique, some of which are inherent. The ability to do this type of analysis is important to a wide range of market participants and other stakeholders, and it may have a role in complementing use of or providing

  7. Bayesian analysis of stage-fall-discharge rating curves and their uncertainties

    Mansanarez, Valentin; Le Coz, Jérôme; Renard, Benjamin; Lang, Michel; Pierrefeu, Gilles; Le Boursicaud, Raphaël; Pobanz, Karine

    2016-04-01

    Stage-fall-discharge (SFD) rating curves are traditionally used to compute streamflow records at sites where the energy slope of the flow is variable due to variable backwater effects. Building on existing Bayesian approaches, we introduce an original hydraulics-based method for developing SFD rating curves used at twin gauge stations and estimating their uncertainties. Conventional power functions for channel and section controls are used, and transition to a backwater-affected channel control is computed based on a continuity condition, solved either analytically or numerically. The difference between the reference levels at the two stations is estimated as another uncertain parameter of the SFD model. The method proposed in this presentation incorporates information from both the hydraulic knowledge (equations of channel or section controls) and the information available in the stage-fall-discharge observations (gauging data). The obtained total uncertainty combines the parametric uncertainty and the remnant uncertainty related to the model of rating curve. This method provides a direct estimation of the physical inputs of the rating curve (roughness, width, slope bed, distance between twin gauges, etc.). The performance of the new method is tested using an application case affected by the variable backwater of a run-of-the-river dam: the Rhône river at Valence, France. In particular, a sensitivity analysis to the prior information and to the gauging dataset is performed. At that site, the stage-fall-discharge domain is well documented with gaugings conducted over a range of backwater affected and unaffected conditions. The performance of the new model was deemed to be satisfactory. Notably, transition to uniform flow when the overall range of the auxiliary stage is gauged is correctly simulated. The resulting curves are in good agreement with the observations (gaugings) and their uncertainty envelopes are acceptable for computing streamflow records. Similar

  8. Unilateral renal agenesia in the angiographic material and renovascular hypertension

    Stojanov, D.; Lovasic, I.; Dujmovic, M.; Bobinac, D.

    1987-06-01

    Analysis of 1216 abdominal aortographies and selective renovasographies undertaken at the Institute of Radiology, Clinical Hospital Centre Rijeka during the period 1979-1985, was performed. 39 (3,2%) unilateral renal agenesias were established, a percentage that is significantly higher than reported by other authors. Analysis of all angiographic parameters of a single kidney was also worked out. A significanlty high percentage (66,7%) of hypertension was diagnosed in this group. Congenital renal failures make their appearance in the early embryological development and are discovered, if compatible with life, most frequently at an advanced age. Statistical data on the frequency during a lifetime are less reliable because a great number of anomalies are never discovered during a person's life. The etiology of variations and congenital failure of renal arteries is unknown in 90% of the cases, and most of the malformations are without characteristic symptomatology. Since the anatomic relations in anomalous kidney are disturbed, the sign of the disease can develop atypical forms causing frequent errors in diagnosis. The kidney is supplied by numerous lateral branches of the medial sacral artery, i.e. the aorta, during embryological development. Later, some of them degenerate or mutually connect themselves, and the definitive kidney has been usually penetrated by only one artery and one vein on the same side (1). If this is not so, i.e. when the obliterations of caudal metanephogenic arteries are only partially present, then the renal arteries emerge from the iliac or lumbar arteries (2,3). Bilateral renal agenesia is extreme and incompatible with life, and hence of small clinical importance. Unilateral agenesia makes its appearance according to various statistics and authors from the obductional materials in ratio 1:1000 (4,5), clinical ones 1:5000 (6, 7, 8) and the angiographically 1:76(9), more exactly 1:35 cases (10).

  9. Unilateral renal agenesia in the angiographic material and renovascular hypertension

    Stojanov, D.; Lovasic, I.; Dujmovic, M.; Bobinac, D.

    1987-01-01

    Analysis of 1216 abdominal aortographies and selective renovasographies undertaken at the Institute of Radiology, Clinical Hospital Centre Rijeka during the period 1979-1985, was performed. 39 (3,2%) unilateral renal agenesias were established, a percentage that is significantly higher than reported by other authors. Analysis of all angiographic parameters of a single kidney was also worked out. A significanlty high percentage (66,7%) of hypertension was diagnosed in this group. Congenital renal failures make their appearance in the early embryological development and are discovered, if compatible with life, most frequently at an advanced age. Statistical data on the frequency during a lifetime are less reliable because a great number of anomalies are never discovered during a person's life. The etiology of variations and congenital failure of renal arteries is unknown in 90% of the cases, and most of the malformations are without characteristic symptomatology. Since the anatomic relations in anomalous kidney are disturbed, the sign of the disease can develop atypical forms causing frequent errors in diagnosis. The kidney is supplied by numerous lateral branches of the medial sacral artery, i.e. the aorta, during embryological development. Later, some of them degenerate or mutually connect themselves, and the definitive kidney has been usually penetrated by only one artery and one vein on the same side (1). If this is not so, i.e. when the obliterations of caudal metanephogenic arteries are only partially present, then the renal arteries emerge from the iliac or lumbar arteries (2,3). Bilateral renal agenesia is extreme and incompatible with life, and hence of small clinical importance. Unilateral agenesia makes its appearance according to various statistics and authors from the obductional materials in ratio 1:1000 (4,5), clinical ones 1:5000 (6, 7, 8) and the angiographically 1:76(9), more exactly 1:35 cases (10). (orig.)

  10. Thermoluminescence glow curve analysis and CGCD method for erbium doped CaZrO{sub 3} phosphor

    Tiwari, Ratnesh, E-mail: 31rati@gmail.com [Department of Physics, Bhilai Institute of Technology, Raipur, 493661 (India); Chopra, Seema [Department Physics, G.D Goenka Public School (India)

    2016-05-06

    The manuscript report the synthesis, thermoluminescence study at fixed concentration of Er{sup 3+} (1 mol%) doped CaZrO{sub 3} phosphor. The phosphors were prepared by modified solid state reaction method. The powder sample was characterized by thermoluminescence (TL) glow curve analysis. In TL glow curve the optimized concentration in 1mol% for UV irradiated sample. The kinetic parameters were calculated by computerized glow curve deconvolution (CGCD) techniaue. Trapping parameters gives the information of dosimetry loss in prepared phosphor and its usability in environmental monitoring and for personal monitoring. CGCD is the advance tool for analysis of complicated TL glow curves.

  11. Analysis of normalized-characteristic curves and determination of the granulometric state of dissolved uranium dioxides

    Melichar, F.; Neumann, L.

    1977-01-01

    Methods are presented for the analysis of normalized-characteristic curves, which make it possible to determine the granulometric composition of a dissolved polydispersion - the cumulative mass distribution of particles - as a function of the relative particle size. If the size of the largest particle in the dissolved polydispersion is known, these methods allow the determination of the dependence of cumulative mass ratios of particles on their absolute sizes. In the inverse method of the geometrical model for determining the granulometric composition of a dissolved polydispersion, the polydispersion is represented by a finite number of monodispersions. An accurate analysis of normalized-characteristic equations leads to the Akselrud dissolution model. As against the other two methods, the latter allows the determination of the granulometric composition for an arbitrary number of particle sizes. The method of the granulometric atlas is a method for estimating the granulometric composition of a dissolved polydispersion and is based on comparison of a normalized-characteristic curve for an unknown granulometric composition with an atlas of normalized-characteristic curves for selected granulometric spectra of polydispersions. (author)

  12. Marginal abatement cost curves for policy recommendation – A method for energy system analysis

    Tomaschek, Jan

    2015-01-01

    The transport sector is seen as one of the key factors for driving future energy consumption and greenhouse gas (GHG) emissions. In order to rank possible measures marginal abatement cost curves have become a tool to graphically represent the relationship between abatement costs and emission reduction. This paper demonstrates how to derive marginal abatement cost curves for well-to-wheel GHG emissions of the transport sector considering the full energy provision chain and the interlinkages and interdependencies within the energy system. Presented marginal abatement cost curves visualize substitution effects between measures for different marginal mitigation costs. The analysis makes use of an application of the energy system model generator TIMES for South Africa (TIMES-GEECO). For the example of Gauteng province, this study exemplary shows that the transport sector is not the first sector to address for cost-efficient reduction of GHG emissions. However, the analysis also demonstrates that several options are available to mitigate transport related GHG emissions at comparable low marginal abatement costs. This methodology can be transferred to other economic sectors as well as to other regions in the world to derive cost-efficient GHG reduction strategies

  13. Silver ion-mediated killing of a food pathogen: Melting curve analysis data of silver resistance genes and growth curve data

    Kuppan Gokulan; Katherine Williams; Sangeeta Khare

    2017-01-01

    Limited antibacterial activity of silver ions leached from silver-impregnated food contact materials could be due to: 1) the presence of silver resistance genes in tested bacteria; or 2) lack of susceptibility to silver ion-mediated killing in the bacterial strain (K. Williams, L. Valencia, K. Gokulan, R. Trbojevich, S. Khare, 2016 [1]). This study contains data to address the specificity of silver resistance genes in Salmonella Typhimurium during the real time PCR using melting curve analysi...

  14. MCNP calculation for calibration curve of X-ray fluorescence analysis

    Tan Chunming; Wu Zhifang; Guo Xiaojing; Xing Guilai; Wang Zhentao

    2011-01-01

    Due to the compositional variation of the sample, linear relationship between the element concentration and fluorescent intensity will not be well maintained in most X-ray fluorescence analysis. To overcome this, we use MCNP program to simulate fluorescent intensity of Fe (0∼100% concentration range) within binary mixture of Cr and O which represent typical strong absorption and weak absorption conditions respectively. The theoretic calculation shows that the relationship can be described as a curve determined by parameter p and value of p can be obtained with given absorption coefficient of substrate elements and element under detection. MCNP simulation results are consistent with theoretic calculation. Our research reveals that MCNP program can calculate the Calibration Curve of X-ray fluorescence very well. (authors)

  15. Obtaining DDF Curves of Extreme Rainfall Data Using Bivariate Copula and Frequency Analysis

    Sadri, Sara; Madsen, Henrik; Mikkelsen, Peter Steen

    2009-01-01

    , situated near Copenhagen in Denmark. For rainfall extracted using method 2, the marginal distribution of depth was found to fit the Generalized Pareto distribution while duration was found to fit the Gamma distribution, using the method of L-moments. The volume was fit with a generalized Pareto...... with duration for a given return period and name them DDF (depth-duration-frequency) curves. The copula approach does not assume the rainfall variables are independent or jointly normally distributed. Rainfall series are extracted in three ways: (1) by maximum mean intensity; (2) by depth and duration...... distribution and the duration was fit with a Pearson type III distribution for rainfall extracted using method 3. The Clayton copula was found to be appropriate for bivariate analysis of rainfall depth and duration for both methods 2 and 3. DDF curves derived using the Clayton copula for depth and duration...

  16. Mathematical analysis of 51Cr-labelled red cell survival curves in congenital haemolytic anaemias

    Kasfiki, A.G.; Antipas, S.E.; Dimitriou, P.A.; Gritzali, F.A.; Melissinos, K.G.

    1982-01-01

    The parameters of 51 Cr labelled red cell survival curves were calculated in 26 patients with homozygous β-thalassaemia, 8 with sickle-cell anaemia and 3 with s-β-thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shorting of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s-β-thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors. (orig.)

  17. Evaluation of the learning curve for external cephalic version using cumulative sum analysis.

    Kim, So Yun; Han, Jung Yeol; Chang, Eun Hye; Kwak, Dong Wook; Ahn, Hyun Kyung; Ryu, Hyun Mi; Kim, Moon Young

    2017-07-01

    We evaluated the learning curve for external cephalic version (ECV) using learning curve-cumulative sum (LC-CUSUM) analysis. This was a retrospective study involving 290 consecutive cases between October 2013 and March 2017. We evaluated the learning curve for ECV on nulli and over para 1 group using LC-CUSUM analysis on the assumption that 50% and 70% of ECV procedures succeeded by description a trend-line of quadratic function with reliable R 2 values. The overall success rate for ECV was 64.8% (188/290), while the success rate for nullipara and over para 1 groups was 56.2% (100/178) and 78.6% (88/112), respectively. 'H' value, that the actual failure rate does not differ from the acceptable failure rate, was -3.27 and -1.635 when considering ECV success rates of 50% and 70%, respectively. Consequently, in order to obtain a consistent 50% success rate, we would require 57 nullipara cases, and in order to obtain a consistent 70% success rate, we would require 130 nullipara cases. In contrast, 8 to 10 over para 1 cases would be required for an expected success rate of 50% and 70% on over para 1 group. Even a relatively inexperienced physician can experience success with multipara and after accumulating experience, they will manage nullipara cases. Further research is required for LC-CUSUM involving several practitioners instead of a single practitioner. This will lead to the gradual implementation of standard learning curve guidelines for ECV.

  18. The angiographic demonstration of hepatic vein obstruction

    Zu Maoheng; Xu Hao; Li Guojun; Gu Yuming; Wei Ning; Wang Cheng; Xu Wei

    2004-01-01

    Objective: To evaluate the angiographic feature of hepatic vein obstruction. Methods Forty-five patients (male 23, female 22, age 9-54 years) suffered from hepatic vein obstruction. The inferior vena cavography and the hepatic venography were performed in all cases. Results: IVC was free in 37 patients with hepatic vein obstruction, both IVC and HV were obstructed in 8 patients. The local or long stenosis of IVC was found in 31 inferior vena cavography. The diameter of IVC was normal in 12 patients. The sign of membranous dome was found in hepatic vein orifice in 5 cases and in accessory hepatic vein orifice in 4 cases. Intrahepatic venous collaterals were found in 45 cases. Conclusion: Hepatic vein obstruction can be reproached primarily in inferior vena cavography, the membranous dome is a direct sign of membranous obstruction of HV and AHV in inferior vena cavography. The selected hepatic venography can provide reliable evidence to diagnose hepatic vein obstruction

  19. Global collapse and J integral analysis for inner-diameter defected curved plates in tension

    Hertelé, Stijn; Verstraete, Matthias; Denys, Rudi; De Waele, Wim

    2013-01-01

    Reference stress equations are widely used to predict both the limit load and the J integral response of defected structures. Their validity is key to performing a safe assessment of structural integrity (plastic collapse and fracture). An analytical reference stress equation based upon global collapse has recently been developed for curved plates with a part-through defect located at the inner diameter surface. This equation predicts decreasing reference stress values as plate curvature increases. To qualify the predictions, the authors have performed a series of finite element analyses covering a wide range of possible geometries. This paper compares the numerically obtained limit loads and J integral responses with the analytical predictions of the reference stress equation. The finite element results generally confirm the decrease of reference stress with increasing plate curvature. Highly pronounced differences may occur between flat plates and slightly curved plates. Overall, the analytically predicted decrease in reference stress is overestimated for small defects but is representative for larger defects. -- Highlights: • A reference stress equation for inner-diameter defected curved plates in tension was developed earlier. • The equation predicts a lower reference stress as plate curvature increases. • The analytical predictions are validated through finite element analysis. • Collapse and J integral are insensitive to curvature for small defects. • For large defects, the analytically predicted trend is confirmed

  20. Diagnostic tests’ decision-making rules based upon analysis of ROC-curves

    Л. В. Батюк

    2015-10-01

    Full Text Available In this paper we propose the model which substantiates diagnostics decision making based on the analysis of Receiver Operating Characteristic curves (ROC-curves and predicts optimal values of diagnostic indicators of biomedical information. To assess the quality of the test result prediction the standard criteria of the sensitivity and specificity of the model were used. Values of these criteria were calculated for the cases when the sensitivity of the test was greater than specificity by several times, when the number of correct diagnoses was maximal, when the sensitivity of the test was equal to its specificity and the sensitivity of the test was several times greater than the specificity of the test. To assess the significance of the factor characteristics and to compare the prognostic characteristics of models we used mathematical modeling and plotting the ROC-curves. The optimal value of the diagnostic indicator was found to be achieved when the sensitivity of the test is equal to its specificity. The model was adapted to solve the case when the sensitivity of the test is greater than specificity of the test.

  1. Numerical analysis of transient heat conduction in downward-facing curved sections during quenching

    Gao, C.; El-Genk, M.S.

    1996-01-01

    Pool boiling from downward-facing surfaces is of interest in many applications such as cooling of electric cables, handling of containers of hazardous liquids and external cooling of nuclear reactor vessels. Here, a two-dimensional numerical analysis was performed to determine pool boiling curves from downward-facing curved stainless-steel and copper surfaces during quenching in saturated water. To ensure stability and accuracy of the numerical solution, the alternating direction implicit (ADI) method based on finite control volume representations was employed. A time dependent boundary condition was provided by the measured temperature at nine interior locations near the boiling surface. Best results were obtained using a grid of 20x20 CVs and a non-iterative approach. Calculated temperatures near the top surface of the metal sections agreed with measured values to within 0.5 K and 2.5 K for the copper and stainless-steel sections, respectively. The running time on a Pentium 90 MHz PC for the entire boiling curve was 7% of the real transient time and 4% of that of a simplified Gaussian elimination (SGE) method for the Crank-Nicolson scheme

  2. STR melting curve analysis as a genetic screening tool for crime scene samples.

    Nguyen, Quang; McKinney, Jason; Johnson, Donald J; Roberts, Katherine A; Hardy, Winters R

    2012-07-01

    In this proof-of-concept study, high-resolution melt curve (HRMC) analysis was investigated as a postquantification screening tool to discriminate human CSF1PO and THO1 genotypes amplified with mini-STR primers in the presence of SYBR Green or LCGreen Plus dyes. A total of 12 CSF1PO and 11 HUMTHO1 genotypes were analyzed on the LightScanner HR96 and LS-32 systems and were correctly differentiated based upon their respective melt profiles. Short STR amplicon melt curves were affected by repeat number, and single-source and mixed DNA samples were additionally differentiated by the formation of heteroduplexes. Melting curves were shown to be unique and reproducible from DNA quantities ranging from 20 to 0.4 ng and distinguished identical from nonidentical genotypes from DNA derived from different biological fluids and compromised samples. Thus, a method is described which can assess both the quantity and the possible probative value of samples without full genotyping. 2012 American Academy of Forensic Sciences. Published 2012. This article is a U.S. Government work and is in the public domain in the U.S.A.

  3. Angiographic features of rapidly involuting congenital hemangioma (RICH)

    Konez, Orhan; Burrows, Patricia E. [Department of Radiology, Children' s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Mulliken, John B. [Division of Plastic Surgery, Children' s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Fishman, Steven J. [Department of Pediatric Surgery, Children' s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Kozakewich, Harry P.W. [Department of Pathology, Children' s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States)

    2003-01-01

    Rapidly involuting congenital hemangioma (RICH) is a recently recognized entity in which the vascular tumor is fully developed at birth and undergoes rapid involution. Angiographic findings in two infants with congenital hemangioma are reported and compared with a more common postnatal infantile hemangioma and a congenital infantile fibrosarcoma. Congenital hemangiomas differed from infantile hemangiomas angiographically by inhomogeneous parenchymal staining, large and irregular feeding arteries in disorganized patterns, arterial aneurysms, direct arteriovenous shunts, and intravascular thrombi. Both infants had clinical evidence of a high-output cardiac failure and intralesional bleeding. This congenital high-flow vascular tumor is difficult to distinguish angiographically from arteriovenous malformation and congenital infantile fibrosarcoma. (orig.)

  4. The Carnegie Supernova Project I. Analysis of stripped-envelope supernova light curves

    Taddia, F.; Stritzinger, M. D.; Bersten, M.; Baron, E.; Burns, C.; Contreras, C.; Holmbo, S.; Hsiao, E. Y.; Morrell, N.; Phillips, M. M.; Sollerman, J.; Suntzeff, N. B.

    2018-02-01

    Stripped-envelope (SE) supernovae (SNe) include H-poor (Type IIb), H-free (Type Ib), and He-free (Type Ic) events thought to be associated with the deaths of massive stars. The exact nature of their progenitors is a matter of debate with several lines of evidence pointing towards intermediate mass (MinitCarnegie Supernova Project (CSP-I) that are unparalleled in terms of photometric accuracy and wavelength range. Light-curve parameters are estimated through the fits of an analytical function and trends are searched for among the resulting fit parameters. Detailed inspection of the dataset suggests a tentative correlation between the peak absolute B-band magnitude and Δm15(B), while the post maximum light curves reveals a correlation between the late-time linear slope and Δm15. Making use of the full set of optical and near-IR photometry, combined with robust host-galaxy extinction corrections, comprehensive bolometric light curves are constructed and compared to both analytic and hydrodynamical models. This analysis finds consistent results among the two different modeling techniques and from the hydrodynamical models we obtained ejecta masses of 1.1-6.2M⊙, 56Ni masses of 0.03-0.35M⊙, and explosion energies (excluding two SNe Ic-BL) of 0.25-3.0 × 1051 erg. Our analysis indicates that adopting κ = 0.07 cm2 g-1 as the mean opacity serves to be a suitable assumption when comparing Arnett-model results to those obtained from hydrodynamical calculations. We also find that adopting He I and O I line velocities to infer the expansion velocity in He-rich and He-poor SNe, respectively, provides ejecta masses relatively similar to those obtained by using the Fe II line velocities, although the use of Fe II as a diagnostic does imply higher explosion energies. The inferred range of ejecta masses are compatible with intermediate mass (MZAMS ≤ 20M⊙) progenitor stars in binary systems for the majority of SE SNe. Furthermore, our hydrodynamical modeling of the

  5. Parameter Deduction and Accuracy Analysis of Track Beam Curves in Straddle-type Monorail Systems

    Xiaobo Zhao

    2015-12-01

    Full Text Available The accuracy of the bottom curve of a PC track beam is strongly related to the production quality of the entire beam. Many factors may affect the parameters of the bottom curve, such as the superelevation of the curve and the deformation of a PC track beam. At present, no effective method has been developed to determine the bottom curve of a PC track beam; therefore, a new technique is presented in this paper to deduce the parameters of such a curve and to control the accuracy of the computation results. First, the domain of the bottom curve of a PC track beam is assumed to be a spindle plane. Then, the corresponding supposed top curve domain is determined based on a geometrical relationship that is the opposite of that identified by the conventional method. Second, several optimal points are selected from the supposed top curve domain according to the dichotomy algorithm; the supposed top curve is thus generated by connecting these points. Finally, one rigorous criterion is established in the fractal dimension to assess the accuracy of the assumed top curve deduced in the previous step. If this supposed curve coincides completely with the known top curve, then the assumed bottom curve corresponding to the assumed top curve is considered to be the real bottom curve. This technique of determining the bottom curve of a PC track beam is thus proven to be efficient and accurate.

  6. Diagnostic accuracy of quantitative 99mTc-MIBI scintimammography according to ROC curve analysis

    Kim, J. H.; Lee, H. K.; Seo, J. W.; Cho, N. S.; Cha, K. H.; Lee, T. H.

    1998-01-01

    99mTc-sestamibi scintimammography (SMM) has been shown to be a useful diagnostic test in the detection of breast cancer and the receiver operating characteristic (ROC) curve analysis provides detailed information of a diagnostic test. The purpose of this study was to evaluate the feasibility and efficacy of quantitative indices of SMM in the detection of malignant breast lesions according to ROC analysis. Prone anterior, lateral planar and supine SPECT imagings were performed on 75 female patients (mean age=43.4 yr) with breast mass (size≥0.8cm) after intravenous injection of 20-30 mCi 99mTc-sestamibi. 45 Malignant (Invasive ductal ca(36), Inv lobular ca(5), Inv duc + lob (1), Inv tubular ca (3)) and 30 benign (fibroadenoma (13), fib cyst(12), Fat necrosis(3), papilloma(1), paraffinoma (1)) lesions were histologically proven. Data were analyzed by creating three regions of interest (ROIs) over designated areas: lesion, normal breast and right chest wall. Lesion to normal (L/NL) and lesion to chest wall (L/CW) ratios were calculated for each patient both on the planar and SPECT. The area under the ROC curve (AUC) was calculated and compared among four semiquantitative indices and an average scintimammographic index (SMM(mean)) from arithmatic mean. ROC curve analysis revealed planar L/N, SPECT L/N and L/CW ratios provide comparable better diagnostic accuracies for detection of breast cancer than planar L/CW ratio (p<0.05), respectively. For quantitative SMM of 75 lesions, malignancy rate was 60%, and Sensitivity, Specificity, Positive Predictive Value, Negative Predictive Value and Accuracy were 0.78, 0.77, 0.84, 0.72 and 0.77, respectively. Quantitative SMM is an useful objective method for differentiating malignant from benign breast lesions

  7. Diagnostic accuracy of quantitative 99mTc-MIBI scintimammography according to ROC curve analysis

    Kim, J. H.; Lee, H. K.; Seo, J. W.; Cho, N. S.; Cha, K. H.; Lee, T. H. [Gachon Medical College, Gil Medical Center, Inchon (Korea, Republic of)

    1998-07-01

    99mTc-sestamibi scintimammography (SMM) has been shown to be a useful diagnostic test in the detection of breast cancer and the receiver operating characteristic (ROC) curve analysis provides detailed information of a diagnostic test. The purpose of this study was to evaluate the feasibility and efficacy of quantitative indices of SMM in the detection of malignant breast lesions according to ROC analysis. Prone anterior, lateral planar and supine SPECT imagings were performed on 75 female patients (mean age=43.4 yr) with breast mass (size{>=}0.8cm) after intravenous injection of 20-30 mCi 99mTc-sestamibi. 45 Malignant (Invasive ductal ca(36), Inv lobular ca(5), Inv duc + lob (1), Inv tubular ca (3)) and 30 benign (fibroadenoma (13), fib cyst(12), Fat necrosis(3), papilloma(1), paraffinoma (1)) lesions were histologically proven. Data were analyzed by creating three regions of interest (ROIs) over designated areas: lesion, normal breast and right chest wall. Lesion to normal (L/NL) and lesion to chest wall (L/CW) ratios were calculated for each patient both on the planar and SPECT. The area under the ROC curve (AUC) was calculated and compared among four semiquantitative indices and an average scintimammographic index (SMM(mean)) from arithmatic mean. ROC curve analysis revealed planar L/N, SPECT L/N and L/CW ratios provide comparable better diagnostic accuracies for detection of breast cancer than planar L/CW ratio (p<0.05), respectively. For quantitative SMM of 75 lesions, malignancy rate was 60%, and Sensitivity, Specificity, Positive Predictive Value, Negative Predictive Value and Accuracy were 0.78, 0.77, 0.84, 0.72 and 0.77, respectively. Quantitative SMM is an useful objective method for differentiating malignant from benign breast lesions.

  8. Enhanced secondary analysis of survival data: reconstructing the data from published Kaplan-Meier survival curves

    Guyot Patricia

    2012-02-01

    Full Text Available Abstract Background The results of Randomized Controlled Trials (RCTs on time-to-event outcomes that are usually reported are median time to events and Cox Hazard Ratio. These do not constitute the sufficient statistics required for meta-analysis or cost-effectiveness analysis, and their use in secondary analyses requires strong assumptions that may not have been adequately tested. In order to enhance the quality of secondary data analyses, we propose a method which derives from the published Kaplan Meier survival curves a close approximation to the original individual patient time-to-event data from which they were generated. Methods We develop an algorithm that maps from digitised curves back to KM data by finding numerical solutions to the inverted KM equations, using where available information on number of events and numbers at risk. The reproducibility and accuracy of survival probabilities, median survival times and hazard ratios based on reconstructed KM data was assessed by comparing published statistics (survival probabilities, medians and hazard ratios with statistics based on repeated reconstructions by multiple observers. Results The validation exercise established there was no material systematic error and that there was a high degree of reproducibility for all statistics. Accuracy was excellent for survival probabilities and medians, for hazard ratios reasonable accuracy can only be obtained if at least numbers at risk or total number of events are reported. Conclusion The algorithm is a reliable tool for meta-analysis and cost-effectiveness analyses of RCTs reporting time-to-event data. It is recommended that all RCTs should report information on numbers at risk and total number of events alongside KM curves.

  9. Enhanced secondary analysis of survival data: reconstructing the data from published Kaplan-Meier survival curves.

    Guyot, Patricia; Ades, A E; Ouwens, Mario J N M; Welton, Nicky J

    2012-02-01

    The results of Randomized Controlled Trials (RCTs) on time-to-event outcomes that are usually reported are median time to events and Cox Hazard Ratio. These do not constitute the sufficient statistics required for meta-analysis or cost-effectiveness analysis, and their use in secondary analyses requires strong assumptions that may not have been adequately tested. In order to enhance the quality of secondary data analyses, we propose a method which derives from the published Kaplan Meier survival curves a close approximation to the original individual patient time-to-event data from which they were generated. We develop an algorithm that maps from digitised curves back to KM data by finding numerical solutions to the inverted KM equations, using where available information on number of events and numbers at risk. The reproducibility and accuracy of survival probabilities, median survival times and hazard ratios based on reconstructed KM data was assessed by comparing published statistics (survival probabilities, medians and hazard ratios) with statistics based on repeated reconstructions by multiple observers. The validation exercise established there was no material systematic error and that there was a high degree of reproducibility for all statistics. Accuracy was excellent for survival probabilities and medians, for hazard ratios reasonable accuracy can only be obtained if at least numbers at risk or total number of events are reported. The algorithm is a reliable tool for meta-analysis and cost-effectiveness analyses of RCTs reporting time-to-event data. It is recommended that all RCTs should report information on numbers at risk and total number of events alongside KM curves.

  10. Composite beam analysis linear analysis of naturally curved and twisted anisotropic beams

    Borri, Marco; Ghiringhelli, Gian L.; Merlini, Teodoro

    1992-05-01

    The aim of this report is to present a consistent theory for the deformation of a naturally curved and twisted anisotropic beam. The proposed formulation naturally extends the classical Saint-Venant approach to the case of curved and twisted anisotropic beams. The mathematical model developed under the assumption of span-wise uniform cross-section, curvature and twist, can take into account any kind of elastic coupling due to the material properties and the curved geometry. The consistency of the presented math-model and its generality about the cross-sectional shape, make it a useful tool even in a preliminary design optimization context such as the aeroelastic tailoring of helicopter rotor blades. The advantage of the present procedure is that it only requires a two-dimensional discretization; thus, very detailed analyses can be performed and interlaminar stresses between laminae can be evaluated. Such analyses would be extremely time consuming if performed with standard finite element codes: that prevents their recursive use as for example when optimizing a beam design. Moreover, as a byproduct of the proposed formulation, one obtains the constitutive law of the cross-section in terms of stress resultant and moment and their conjugate strain measures. This constitutive law takes into account any kind of elastic couplings, e.g., torsion-tension, tension-shear, bending-shear, and constitutes a fundamental input in aeroelastic analyses of helicopter blades. Four simple examples are given in order to show the principal features of the method.

  11. Polygonal approximation and scale-space analysis of closed digital curves

    Ray, Kumar S

    2013-01-01

    This book covers the most important topics in the area of pattern recognition, object recognition, computer vision, robot vision, medical computing, computational geometry, and bioinformatics systems. Students and researchers will find a comprehensive treatment of polygonal approximation and its real life applications. The book not only explains the theoretical aspects but also presents applications with detailed design parameters. The systematic development of the concept of polygonal approximation of digital curves and its scale-space analysis are useful and attractive to scholars in many fi

  12. Optimized curve design for image analysis using localized geodesic distance transformations

    Braithwaite, Billy; Niska, Harri; Pöllänen, Irene; Ikonen, Tiia; Haataja, Keijo; Toivanen, Pekka; Tolonen, Teemu

    2015-03-01

    We consider geodesic distance transformations for digital images. Given a M × N digital image, a distance image is produced by evaluating local pixel distances. Distance Transformation on Curved Space (DTOCS) evaluates shortest geodesics of a given pixel neighborhood by evaluating the height displacements between pixels. In this paper, we propose an optimization framework for geodesic distance transformations in a pattern recognition scheme, yielding more accurate machine learning based image analysis, exemplifying initial experiments using complex breast cancer images. Furthermore, we will outline future research work, which will complete the research work done for this paper.

  13. Measurement and analysis of field-induced crystallographic texture using curved position-sensitive diffraction detectors

    Simons, Hugh; Daniels, John E.; Studer, Andrew J.

    2014-01-01

    This paper outlines measurement and analysis methodologies created for determining the structural responses of electroceramics to an electric field. A sample stage is developed to apply electric fields to ceramic materials at elevated temperatures during neutron diffraction experiments. The tested...... employing a curved positive sensitive detector. Methodologies are proposed to account for the geometrical effects when vector fields are applied to textured materials with angularly dispersive detector geometries. Representative results are presented for the ferroelectric (Bi1/2Na1/2)TiO3-6%BaTiO3 (BNT-6BT...

  14. Analyzing Multiple-Choice Questions by Model Analysis and Item Response Curves

    Wattanakasiwich, P.; Ananta, S.

    2010-07-01

    In physics education research, the main goal is to improve physics teaching so that most students understand physics conceptually and be able to apply concepts in solving problems. Therefore many multiple-choice instruments were developed to probe students' conceptual understanding in various topics. Two techniques including model analysis and item response curves were used to analyze students' responses from Force and Motion Conceptual Evaluation (FMCE). For this study FMCE data from more than 1000 students at Chiang Mai University were collected over the past three years. With model analysis, we can obtain students' alternative knowledge and the probabilities for students to use such knowledge in a range of equivalent contexts. The model analysis consists of two algorithms—concentration factor and model estimation. This paper only presents results from using the model estimation algorithm to obtain a model plot. The plot helps to identify a class model state whether it is in the misconception region or not. Item response curve (IRC) derived from item response theory is a plot between percentages of students selecting a particular choice versus their total score. Pros and cons of both techniques are compared and discussed.

  15. Analysis of demand curves in the stock and financial markets of monopolistic competition

    Mikhail I. Geras’kin

    2016-01-01

    Full Text Available Objective to identify patterns of monopolistic competition as applied to markets of household appliances consumer loans and insurance products in Russia. Methods econometric modeling trending regression analysis analysis of statistical significance. Results the statistical analysis of trends in the market of household appliances insurance and credit markets has been carried out the statistical significance and adequacy of the models has been assessed adequate and accurate regression models of price trends of household appliances and electronics have been developed as well as of the interest rates of consumer loans and insurance rates for loan debts. Scientific novelty the actual patterns of decreasing demand curves for household appliances consumer loans and insurance products were found for the relevant markets in the Russian Federation in 2009ndash2014. Practical significance the model can be used for solving problems of optimal planning strategies of retailers insurers and banks. nbsp

  16. Parametric analysis of the curved slats fixed mirror solar concentrator for medium temperature applications

    Pujol-Nadal, Ramon; Martínez-Moll, Víctor

    2014-01-01

    Highlights: • We thermally modeled the Curved Slats Fixed Mirror Solar Concentrator (CSFMSC). • A parametric analysis for three climates and two axial orientations are given. • The optimum values are determined for a range of the design parameters. • The CSFMSC has been well characterized for medium range temperature operation. - Abstract: The Curved Slats Fixed Mirror Solar Concentrator (CSFMSC) is a solar concentrator with a static reflector and a moving receiver. An optical analysis using ray-tracing tools was presented in a previous study in function of three design parameters: the number of mirrors N, the ratio of focal length and reflector width F/W, and the aperture concentration C a . However, less is known about the thermal behavior of this geometry. In this communication, the integrated thermal output of the CSFMSC has been determined in order to find the optimal values for the design parameters at a working temperature of 200 °C. The results were obtained for three different climates and two axial orientations (North–South, and East–West). The results show that CSFMSC can produce heat at 200 °C with an annual thermal efficiency of 41, 47, and 51%, dependent of the location considered (Munich, Palma de Mallorca, and Cairo). The best FMSC geometries in function of the design parameters are exhibited for medium temperature applications

  17. Application of a logistic function to the analysis of contrast-detail curves

    Mumma, C.G.; Prince, J.R.

    1987-01-01

    A general logistic function has been applied to the regression analysis of radioscintigraphic contrast-detail (CD) curves obtained in the authors' laboratory and to previously published results in assorted imaging modalities. Regression analysis is based on the logistic function: d/sub min/ = d/sub min//sup sat/(1 - EXP - (K + CX)), where d/sub min/ is the minimum perceptible detail diameter at a primary contrast X, and d/sub min//sup sat/ is the saturation value of d/sub min/. K and C are regression parameters. Logistic regression in assorted imaging modalities yielded r 2 values ranging from 0.95 to 0.99. A figure of merit (FOM), the area under the CD curve (AUC), is obtained by integrating the logistic function over mathematically and clinically acceptable limits. For count densities of 200 countscm 2 and 1,000 countscm 2 , the AUC differed approximately by a factor of 2. Thus, the AUC may be a sensitive FOM

  18. Nonlinear Analysis and Post-Test Correlation for a Curved PRSEUS Panel

    Gould, Kevin; Lovejoy, Andrew E.; Jegley, Dawn; Neal, Albert L.; Linton, Kim, A.; Bergan, Andrew C.; Bakuckas, John G., Jr.

    2013-01-01

    The Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept, developed by The Boeing Company, has been extensively studied as part of the National Aeronautics and Space Administration's (NASA s) Environmentally Responsible Aviation (ERA) Program. The PRSEUS concept provides a light-weight alternative to aluminum or traditional composite design concepts and is applicable to traditional-shaped fuselage barrels and wings, as well as advanced configurations such as a hybrid wing body or truss braced wings. Therefore, NASA, the Federal Aviation Administration (FAA) and The Boeing Company partnered in an effort to assess the performance and damage arrestments capabilities of a PRSEUS concept panel using a full-scale curved panel in the FAA Full-Scale Aircraft Structural Test Evaluation and Research (FASTER) facility. Testing was conducted in the FASTER facility by subjecting the panel to axial tension loads applied to the ends of the panel, internal pressure, and combined axial tension and internal pressure loadings. Additionally, reactive hoop loads were applied to the skin and frames of the panel along its edges. The panel successfully supported the required design loads in the pristine condition and with a severed stiffener. The panel also demonstrated that the PRSEUS concept could arrest the progression of damage including crack arrestment and crack turning. This paper presents the nonlinear post-test analysis and correlation with test results for the curved PRSEUS panel. It is shown that nonlinear analysis can accurately calculate the behavior of a PRSEUS panel under tension, pressure and combined loading conditions.

  19. Probing Birth-Order Effects on Narrow Traits Using Specification-Curve Analysis.

    Rohrer, Julia M; Egloff, Boris; Schmukle, Stefan C

    2017-12-01

    The idea that birth-order position has a lasting impact on personality has been discussed for the past 100 years. Recent large-scale studies have indicated that birth-order effects on the Big Five personality traits are negligible. In the current study, we examined a variety of more narrow personality traits in a large representative sample ( n = 6,500-10,500 in between-family analyses; n = 900-1,200 in within-family analyses). We used specification-curve analysis to assess evidence for birth-order effects across a range of models implementing defensible yet arbitrary analytical decisions (e.g., whether to control for age effects or to exclude participants on the basis of sibling spacing). Although specification-curve analysis clearly confirmed the previously reported birth-order effect on intellect, we found no meaningful effects on life satisfaction, locus of control, interpersonal trust, reciprocity, risk taking, patience, impulsivity, or political orientation. The lack of meaningful birth-order effects on self-reports of personality was not limited to broad traits but also held for more narrowly defined characteristics.

  20. Antigen-antibody biorecognition events as discriminated by noise analysis of force spectroscopy curves.

    Bizzarri, Anna Rita; Cannistraro, Salvatore

    2014-08-22

    Atomic force spectroscopy is able to extract kinetic and thermodynamic parameters of biomolecular complexes provided that the registered unbinding force curves could be reliably attributed to the rupture of the specific complex interactions. To this aim, a commonly used strategy is based on the analysis of the stretching features of polymeric linkers which are suitably introduced in the biomolecule-substrate immobilization procedure. Alternatively, we present a method to select force curves corresponding to specific biorecognition events, which relies on a careful analysis of the force fluctuations of the biomolecule-functionalized cantilever tip during its approach to the partner molecules immobilized on a substrate. In the low frequency region, a characteristic 1/f (α) noise with α equal to one (flickering noise) is found to replace white noise in the cantilever fluctuation power spectrum when, and only when, a specific biorecognition process between the partners occurs. The method, which has been validated on a well-characterized antigen-antibody complex, represents a fast, yet reliable alternative to the use of linkers which may involve additional surface chemistry and reproducibility concerns.

  1. Silver ion-mediated killing of a food pathogen: Melting curve analysis data of silver resistance genes and growth curve data

    Kuppan Gokulan

    2017-04-01

    Full Text Available Limited antibacterial activity of silver ions leached from silver-impregnated food contact materials could be due to: 1 the presence of silver resistance genes in tested bacteria; or 2 lack of susceptibility to silver ion-mediated killing in the bacterial strain (K. Williams, L. Valencia, K. Gokulan, R. Trbojevich, S. Khare, 2016 [1]. This study contains data to address the specificity of silver resistance genes in Salmonella Typhimurium during the real time PCR using melting curve analysis and an assessment of the minimum inhibitory concentration of silver ions for Salmonella.

  2. Silver ion-mediated killing of a food pathogen: Melting curve analysis data of silver resistance genes and growth curve data.

    Gokulan, Kuppan; Williams, Katherine; Khare, Sangeeta

    2017-04-01

    Limited antibacterial activity of silver ions leached from silver-impregnated food contact materials could be due to: 1) the presence of silver resistance genes in tested bacteria ; or 2) lack of susceptibility to silver ion-mediated killing in the bacterial strain (K. Williams, L. Valencia, K. Gokulan, R. Trbojevich, S. Khare, 2016 [1]). This study contains data to address the specificity of silver resistance genes in Salmonella Typhimurium during the real time PCR using melting curve analysis and an assessment of the minimum inhibitory concentration of silver ions for Salmonella .

  3. A Real-Time PCR with Melting Curve Analysis for Molecular Typing of Vibrio parahaemolyticus.

    He, Peiyan; Wang, Henghui; Luo, Jianyong; Yan, Yong; Chen, Zhongwen

    2018-05-23

    Foodborne disease caused by Vibrio parahaemolyticus is a serious public health problem in many countries. Molecular typing has a great scientific significance and application value for epidemiological research of V. parahaemolyticus. In this study, a real-time PCR with melting curve analysis was established for molecular typing of V. parahaemolyticus. Eighteen large variably presented gene clusters (LVPCs) of V. parahaemolyticus which have different distributions in the genome of different strains were selected as targets. Primer pairs of 18 LVPCs were distributed into three tubes. To validate this newly developed assay, we tested 53 Vibrio parahaemolyticus strains, which were classified in 13 different types. Furthermore, cluster analysis using NTSYS PC 2.02 software could divide 53 V. parahaemolyticus strains into six clusters at a relative similarity coefficient of 0.85. This method is fast, simple, and conveniently for molecular typing of V. parahaemolyticus.

  4. Spectral analysis of stellar light curves by means of neural networks

    Tagliaferri, R.; Ciaramella, A.; Milano, L.; Barone, F.; Longo, G.

    1999-06-01

    Periodicity analysis of unevenly collected data is a relevant issue in several scientific fields. In astrophysics, for example, we have to find the fundamental period of light or radial velocity curves which are unevenly sampled observations of stars. Classical spectral analysis methods are unsatisfactory to solve the problem. In this paper we present a neural network based estimator system which performs well the frequency extraction in unevenly sampled signals. It uses an unsupervised Hebbian nonlinear neural algorithm to extract, from the interpolated signal, the principal components which, in turn, are used by the MUSIC frequency estimator algorithm to extract the frequencies. The neural network is tolerant to noise and works well also with few points in the sequence. We benchmark the system on synthetic and real signals with the Periodogram and with the Cramer-Rao lower bound. This work was been partially supported by IIASS, by MURST 40\\% and by the Italian Space Agency.

  5. Incorporating Measurement Non-Equivalence in a Cross-Study Latent Growth Curve Analysis.

    Flora, David B; Curran, Patrick J; Hussong, Andrea M; Edwards, Michael C

    2008-10-01

    A large literature emphasizes the importance of testing for measurement equivalence in scales that may be used as observed variables in structural equation modeling applications. When the same construct is measured across more than one developmental period, as in a longitudinal study, it can be especially critical to establish measurement equivalence, or invariance, across the developmental periods. Similarly, when data from more than one study are combined into a single analysis, it is again important to assess measurement equivalence across the data sources. Yet, how to incorporate non-equivalence when it is discovered is not well described for applied researchers. Here, we present an item response theory approach that can be used to create scale scores from measures while explicitly accounting for non-equivalence. We demonstrate these methods in the context of a latent curve analysis in which data from two separate studies are combined to create a single longitudinal model spanning several developmental periods.

  6. The composition-explicit distillation curve technique: Relating chemical analysis and physical properties of complex fluids.

    Bruno, Thomas J; Ott, Lisa S; Lovestead, Tara M; Huber, Marcia L

    2010-04-16

    The analysis of complex fluids such as crude oils, fuels, vegetable oils and mixed waste streams poses significant challenges arising primarily from the multiplicity of components, the different properties of the components (polarity, polarizability, etc.) and matrix properties. We have recently introduced an analytical strategy that simplifies many of these analyses, and provides the added potential of linking compositional information with physical property information. This aspect can be used to facilitate equation of state development for the complex fluids. In addition to chemical characterization, the approach provides the ability to calculate thermodynamic properties for such complex heterogeneous streams. The technique is based on the advanced distillation curve (ADC) metrology, which separates a complex fluid by distillation into fractions that are sampled, and for which thermodynamically consistent temperatures are measured at atmospheric pressure. The collected sample fractions can be analyzed by any method that is appropriate. The analytical methods we have applied include gas chromatography (with flame ionization, mass spectrometric and sulfur chemiluminescence detection), thin layer chromatography, FTIR, corrosivity analysis, neutron activation analysis and cold neutron prompt gamma activation analysis. By far, the most widely used analytical technique we have used with the ADC is gas chromatography. This has enabled us to study finished fuels (gasoline, diesel fuels, aviation fuels, rocket propellants), crude oils (including a crude oil made from swine manure) and waste oils streams (used automotive and transformer oils). In this special issue of the Journal of Chromatography, specifically dedicated to extraction technologies, we describe the essential features of the advanced distillation curve metrology as an analytical strategy for complex fluids. Published by Elsevier B.V.

  7. Angiographic diagnosis of the prehepatic portal hypertension

    Carnevali, G.; Brambilla, G.

    1981-01-01

    After the experience gained in the examination of more than 400 patients with portal hypertension, one can say that thrombosis is a factor not to be neglected. It appeared in 25% of all cases, in 50% of all cases as a cause of liver cirrhosis. The representation of the vena coeliaca mesentenica is essential for a reliable detection of thrombosis. Splenoportography is less frequently applied due to the known contraindications and is restricted to more demanding and complex problems. The detection of thrombotic changes is also important because such areas prohibit surgical measures such as by-passes. Also important is the preventive discovery of a portal thrombosis in the course of a complicated, bleeding liver cirrhosis. A pre-operative angiographic diagnosis is necessary in planned portocaval shunt procedures of cirrholic liver alterations. The surgeon has to know beforehand whether pyle thrombosis can be excluded or detected. In the latter case, a thrombotectomy has to be performed, which, however, does not impede good treatment results. (orig./MG) [de

  8. Angiographic diagnosis of the prehepatic portal hypertension

    Carnevali, G; Brambilla, G

    1981-01-01

    After the experience gained in the examination of more than 400 patients with portal hypertension, one can say that thrombosis is a factor not to be neglected. It appeared in 25% of all cases and in 50% of all cases as a cause of liver cirrhosis. The representation of the vena coeliaca mesentenica is essential for a reliable detection of thrombosis. Splenoportography is less frequently applied due to the known contraindications and is restricted to more demanding and complex problems. The detection of thrombotic changes is also important because such areas prohibit surgical measures such as by-passes. Also important is the preventive discovery of a portal thrombosis in the course of a complicated, bleeding liver cirrhosis. A pre-operative angiographic diagnosis is necessary in planned portocaval shunt procedures of cirrholic liver alterations. The surgeon has to know beforehand whether pyle thrombosis can be excluded or detected. In the latter case, a thrombotectomy has to be performed, which, however, does not impede good treatment results.

  9. Angiographic patterns of carotid-cavernous fistulas

    Georgieva, G.; Jekova, M.; Genov, P.; Hadjidekov, V.

    2006-01-01

    Full text: The aim of the study is to present our experience in angiographic evaluation of carotid-cavernous fistulas. 8 patients with carotid-cavernous fistula (6 men and 2 women, range of age from 15 to 62) are included in the study out of all undergone cerebral angiography for a four year period (1996 - 2000). All patients underwent CT brain examination, two out of 8 - MRI. Visualization of ipsi- and contra lateral cavernous sinus and ophthalmic vein dilatation are assessed. In all cases the communication between the internal carotid artery and the cavernous sinus has been assessed as direct. Near simultaneous visualization of the home internal carotid artery, the dilated ipsilateral cavernous sinus and dilated superior ophthalmic vein is found in 2 patients, simultaneous visualization of both cavernous sinuses - in two. In 1 patient the early visualization of the cavernous sinus through the fistula enabled visualization of ipsilateral main internal carotid artery from the contra lateral circulation through the communicating arteries.In 1 excessive contralateral cavernous sinus and contralateral superior ophthalmic vein dilatation is detected. In other 1 excessive flow to dilated ipsilateral cavernous sinus lead insufficient circulation in distal vessels. Digital subtraction Angiography remains the most suitable imaging method in carotid-cavernous fistula assessment regarding type of communication and level of following vessels morphology changes

  10. Evaluation of angiographic delayed vasospasm due to ruptured aneurysm in comparison with cerebral circulation time measured by IA-DSA

    Okada, Yoshikazu; Shima, Takeshi; Nishida, Masahiro; Yamane, Kanji; Okita, Shinji; Hatayama, Takashi; Yoshida, Akira; Naoe, Yasutaka; Shiga, Naoko (Chugoku Rosai Hospital, Hiroshima (Japan))

    1994-05-01

    Delayed vasospasm due to ruptured aneurysm has been basically evaluated by angiographic changes in contrast to clinical features such as delayed ischemic neurological deficits (DIND). However, the discrepancies between angiographic and clinical findings have been pointed out. In this study, angiographic changes and cerebral circulation time in ruptured aneurysms were simultaneously investigated with IA-DSA. Thirty-two patients, who had ruptured aneurysms at the anterior circle of Willis and neck clippings at the acute stage, were investigated. Carotid angiogram was performed with IA-DSA on the 7-13th day after the attack. Angiographic changes were evaluated by Fischer's classification and circulation time was calculated in the following way. A time-density curve was obtained at the two ROI's: the C3-C4 portion and the rolandic vein. Circulation time was defined by the difference between the time showing peak optical density at the carotid and the venous portion. The control value of this circulation time obtained from 20 cases with non-rupture aneurysm and epilepsy was 3.4 sec (53 year old) on the average. X-ray CT scan examination was performed at the same time and clinical features were observed every day. Angiographically, 3 cases were free from vasospasm, 18 cases were found to present slight to moderate vasospasm, and 11 cases showed severe vasospasm. Circulation time in patients with no spasm was 3.6 seconds, in patients with slight to moderate vasospasm it was 4.3 seconds and in patients with severe vasospasm it was 6.8 seconds. Ten patients showing cerebral infarction on CT scans demonstrated significantly long circulation time, 7.0 seconds on the average. And all patients having severe vasospasm with circulation time more than 6 seconds presented DIND such as hemiparesis. (author).

  11. Vibrational Analysis of Curved Single-Walled Carbon Nanotube on a Pasternak Elastic Foundation

    Mehdipour, I.; Barari, Amin; Kimiaeifar, Amin

    2012-01-01

    . By utilizing He’s Energy Balance Method (HEBM), the relationships of the nonlinear amplitude and frequency were expressed for a curved, single-walled carbon nanotube. The amplitude frequency response curves of the nonlinear free vibration were obtained for a curved, single-walled carbon nanotube embedded...

  12. Application of the Learning Curve Analysis to the LHC Main Dipole Production First Assessment

    Fessia, P; Rossi, L

    2006-01-01

    About two third of the LHC main dipoles have been delivered by the three suppliers charged of the production. The training of the staff, mostly hired just for this manufacture, and the natural improvement of the procedures with the acquired experience, decrease naturally the time necessary for the assembly of a unit. The aim of this paper is to apply methodologies like the cost-based learning curves and the time-based learning curves to the LHC Main Dipole comparing the estimated learning percentage to the ones experienced in other industries. This type of analysis, still in a preliminary phase and here applied to about 40% of the total production of the LHC magnets that will end by 2006, shows that our production has a relatively high learning percentage and it is similar to aerospace and complex machine tools for new models. Therefore with the LHC project, accelerator magnets seem to have reached industrial maturity and this production can be used as bench mark for other large scientific projects implying s...

  13. Pressure and pressure derivative analysis for injection tests with variable temperature without type-curve matching

    Escobar, Freddy Humberto; Martinez, Javier Andres; Montealegre Matilde

    2008-01-01

    The analysis of injection tests under nonisothermic conditions is important for the accurate estimation of the reservoir permeability and the well's skin factor; since previously an isothermical system was assumed without taking into account a moving temperature front which expands with time plus the consequent changes in both viscosity and mobility between the cold and the hot zone of the reservoir which leads to unreliable estimation of the reservoir and well parameters. To construct the solution an analytical approach presented by Boughrara and Peres (2007) was used. That solution was initially introduced for the calculation of the injection pressure in an isothermic system. It was later modified by Boughrara and Reynolds (2007) to consider a system with variable temperature in vertical wells. In this work, the pressure response was obtained by numerical solution of the anisothermical model using the Gauss Quadrature method to solve the integrals, and assuming that both injection and reservoir temperatures were kept constant during the injection process and the water saturation is uniform throughout the reservoir. For interpretation purposes, a technique based upon the unique features of the pressure and pressure derivative curves were used without employing type-curve matching (TDS technique). The formulation was verified by its application to field and synthetic examples. As expected, increasing reservoir temperature causes a decrement in the mobility ratio, then estimation of reservoir permeability is some less accurate from the second radial flow, especially, as the mobility ratio increases

  14. Economic growth and CO2 emissions in Malaysia: A cointegration analysis of the Environmental Kuznets Curve

    Saboori, Behnaz; Sulaiman, Jamalludin; Mohd, Saidatulakmal

    2012-01-01

    This paper attempts to establish a long-run as well as causal relationship between economic growth and carbon dioxide (CO 2 ) emissions for Malaysia. Using data for the years from 1980 to 2009, the Environmental Kuznets Curve (EKC) hypothesis was tested utilizing the Auto Regressive Distributed Lag (ARDL) methodology. The empirical results suggest the existence of a long-run relationship between per capita CO 2 emissions and real per capita Gross Domestic Product (GDP) when the CO 2 emissions level is the dependent variable. We found an inverted-U shape relationship between CO 2 emissions and GDP in both short and long-run, thus supporting the EKC hypothesis. The Granger Causality test based on the Vector Error Correction Model (VECM) presents an absence of causality between CO 2 emissions and economic growth in the short-run while demonstrating uni-directional causality from economic growth to CO 2 emissions in the long-run. - Highlights: ► We tested the dynamic relationship between economic growth and CO 2 emissions. ► The Environmental Kuznets Curve hypothesis was tested using bounds testing approach. ► The empirical analysis confirms the existence of EKC for Malaysia. ► Causality results in an absence of causality between CO 2 and income in the short-run. ► There is uni-directional causality from income to CO 2 emissions in the long-run.

  15. Genetic algorithm using independent component analysis in x-ray reflectivity curve fitting of periodic layer structures

    Tiilikainen, J; Bosund, V; Tilli, J-M; Sormunen, J; Mattila, M; Hakkarainen, T; Lipsanen, H

    2007-01-01

    A novel genetic algorithm (GA) utilizing independent component analysis (ICA) was developed for x-ray reflectivity (XRR) curve fitting. EFICA was used to reduce mutual information, or interparameter dependences, during the combinatorial phase. The performance of the new algorithm was studied by fitting trial XRR curves to target curves which were computed using realistic multilayer models. The median convergence properties of conventional GA, GA using principal component analysis and the novel GA were compared. GA using ICA was found to outperform the other methods with problems having 41 parameters or more to be fitted without additional XRR curve calculations. The computational complexity of the conventional methods was linear but the novel method had a quadratic computational complexity due to the applied ICA method which sets a practical limit for the dimensionality of the problem to be solved. However, the novel algorithm had the best capability to extend the fitting analysis based on Parratt's formalism to multiperiodic layer structures

  16. Calibration curves of a PGNAA system for cement raw material analysis using the MCNP code

    Oliveira, Carlos; Salgado, Jose

    1998-01-01

    In large samples, the γ-ray count rate of a prompt gamma neutron activation analysis system is a multi-variable function of the elemental dry composition, density, water content and thickness of the material. The experimental calibration curves require tremendous laboratory work, using a great number of standards with well-known compositions. Although a Monte Carlo simulation study does not avoid the experimental calibration work, it reduces the number of experimental calibration standards. This paper is part of a feasibility study for a PGNAA system for on-line continuous characterisation of cement raw material conveyed on a belt (Oliveira, C., Salgado, J. and Carvalho, F. G. (1997) Optimisation of PGNAA instrument design for cement raw materials using the MCNP code. J. Radioanal. Nucl. Chem. 216(2), 191-198; Oliveira, C., Salgado, J., Goncalves, I. F., Carvalho, F. G. and Leitao, F. (1997a) A Monte Carlo study of the influence of geometry arrangements and structural materials on a PGNAA system performance for cement raw materials analysis. Appl. Radiat. Isot. (accepted); Oliveira, C., Salgado, J. and Leitao, F. (1997b) Density and water content corrections in the gamma count rate of a PGNAA system for cement raw material analysis using the MCNP code. Appl. Radiat. Isot. (accepted).]. It reports on the influence of the density, mass water content and thickness on the calibration curves of the PGNAA system. The MCNP-4A code, running in a Pentium-PC and in a DEC workstation, was used to simulate the PGNAA configuration system

  17. Differentiation of five enterohepatic Helicobacter species by nested PCR with high-resolution melting curve analysis.

    Wu, Miaoli; Rao, Dan; Zhu, Yujun; Wang, Jing; Yuan, Wen; Zhang, Yu; Huang, Ren; Guo, Pengju

    2017-04-01

    Enterohepatic Helicobacter species (EHS) are widespread in rodent species around the world. Several studies have demonstrated that infection with EHS can interfere with the outcomes of animal experiments in cancer research and significantly influence the study results. Therefore, it is essential to establish a rapid detection and identification of EHS for biomedical research using laboratory rodents. Our study aimed to develop a rapid and sensitive method to detect and distinguish five enterohepatic Helicobacter species. Nested PCR followed by high-resolution melting curve analysis (HRM) was developed for identification of H. bilis, H. rodentium, H. muridarum, H. typhlonius, as well as H. hepaticus. To validate the accuracy of nested PCR-HRM analysis, quantitative real-time PCR methods for five different enterohepatic Helicobacter species were developed. A total of 50 cecal samples were tested using both nested PCR-HRM analysis and qPCR method. The nested PCR-HRM method could distinguish five enterohepatic Helicobacter species by different melting temperatures. The melting curve were characterized by peaks of 78.7 ± 0.12°C for H. rodentium, 80.51 ± 0.09°C for H. bilis, 81.6 ± 0.1°C for H. typhlonius, 82.11 ± 0.18°C for H. muridarum, and 82.95 ± 0.09°C for H. hepaticus. The nested PCR-HRM assay is a simple, rapid, and cost-effective assay. This assay could be a useful tool for molecular epidemiology study of enterohepatic Helicobacter infection and an attractive alternative for genotyping of enterohepatic Helicobacter species. © 2016 John Wiley & Sons Ltd.

  18. Differentiation of minute virus of mice and mouse parvovirus by high resolution melting curve analysis.

    Rao, Dan; Wu, Miaoli; Wang, Jing; Yuan, Wen; Zhu, Yujun; Cong, Feng; Xu, Fengjiao; Lian, Yuexiao; Huang, Bihong; Wu, Qiwen; Chen, Meili; Zhang, Yu; Huang, Ren; Guo, Pengju

    2017-12-01

    Murine parvovirus is one of the most prevalent infectious pathogens in mouse colonies. A specific primer pair targeting the VP2 gene of minute virus of mice (MVM) and mouse parvovirus (MPV) was utilized for high resolution melting (HRM) analysis. The resulting melting curves could distinguish these two virus strains and there was no detectable amplification of the other mouse pathogens which included rat parvovirus (KRV), ectromelia virus (ECT), mouse adenovirus (MAD), mouse cytomegalovirus (MCMV), polyoma virus (Poly), Helicobactor hepaticus (H. hepaticus) and Salmonella typhimurium (S. typhimurium). The detection limit of the standard was 10 copies/μL. This study showed that the PCR-HRM assay could be an alternative useful method with high specificity and sensitivity for differentiating murine parvovirus strains MVM and MPV. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Environment Kuznets curve for CO{sub 2} emissions. A cointegration analysis for China

    Jalil, Abdul [Centre for Economic Development Research, Wuhan University, Wuhan 437002 (China); Mahmud, Syed F. [Department of Economics, Bilkent University, Ankara 06800 (Turkey)

    2009-12-15

    This study examines the long-run relationship between carbon emissions and energy consumption, income and foreign trade in the case of China by employing time series data of 1975-2005. In particular the study aims at testing whether environmental Kuznets curve (EKC) relationship between CO{sub 2} emissions and per capita real GDP holds in the long run or not. Auto regressive distributed lag (ARDL) methodology is employed for empirical analysis. A quadratic relationship between income and CO{sub 2} emission has been found for the sample period, supporting EKC relationship. The results of Granger causality tests indicate one way causality runs through economic growth to CO{sub 2} emissions. The results of this study also indicate that the carbon emissions are mainly determined by income and energy consumption in the long run. Trade has a positive but statistically insignificant impact on CO{sub 2} emissions. (author)

  20. Environment Kuznets curve for CO{sub 2} emissions: A cointegration analysis for China

    Jalil, Abdul, E-mail: jalil.hanif@gmail.co [Centre for Economic Development Research, Wuhan University, Wuhan 437002 (China); Mahmud, Syed F., E-mail: syed@bilkent.edu.t [Department of Economics, Bilkent University, Ankara 06800 (Turkey)

    2009-12-15

    This study examines the long-run relationship between carbon emissions and energy consumption, income and foreign trade in the case of China by employing time series data of 1975-2005. In particular the study aims at testing whether environmental Kuznets curve (EKC) relationship between CO{sub 2} emissions and per capita real GDP holds in the long run or not. Auto regressive distributed lag (ARDL) methodology is employed for empirical analysis. A quadratic relationship between income and CO{sub 2} emission has been found for the sample period, supporting EKC relationship. The results of Granger causality tests indicate one way causality runs through economic growth to CO{sub 2} emissions. The results of this study also indicate that the carbon emissions are mainly determined by income and energy consumption in the long run. Trade has a positive but statistically insignificant impact on CO{sub 2} emissions.

  1. Environment Kuznets curve for CO2 emissions: A cointegration analysis for China

    Jalil, Abdul; Mahmud, Syed F.

    2009-01-01

    This study examines the long-run relationship between carbon emissions and energy consumption, income and foreign trade in the case of China by employing time series data of 1975-2005. In particular the study aims at testing whether environmental Kuznets curve (EKC) relationship between CO 2 emissions and per capita real GDP holds in the long run or not. Auto regressive distributed lag (ARDL) methodology is employed for empirical analysis. A quadratic relationship between income and CO 2 emission has been found for the sample period, supporting EKC relationship. The results of Granger causality tests indicate one way causality runs through economic growth to CO 2 emissions. The results of this study also indicate that the carbon emissions are mainly determined by income and energy consumption in the long run. Trade has a positive but statistically insignificant impact on CO 2 emissions.

  2. Radionuclide Angiocardiographic Evaluation of Left-to-Right Cardiac Shunts: Analysis of Time-Active Curves

    Kim, Ok Hwa; Bahk, Yong Whee; Kim, Chi Kyung

    1987-01-01

    The noninvasive nature of the radionuclide angiocardiography provided a useful approach for the evaluation of left-to-right cardiac shunts (LRCS). While the qualitative information can be obtained by inspection of serial radionuclide angiocardiograms, the quantitative information of radionuclide angiocardiography can be obtained by the analysis of time-activity curves using advanced computer system. The count ratios method and pulmonary-to-systemic flow ratio (QP/QS) by gamma variate fit method were used to evaluate the accuracy of detection and localization of LRCS. One hundred and ten time-activity curves were analyzed. There were 46 LRCS (atrial septal defects 11, ventricular septal defects 22, patent ductus arteriosus 13) and 64 normal subjects. By computer analysis of time-activity curves of the right atriurn, ventricle and the lungs separately, the count ratios modified by adding the mean cardiac transit time were calculated in each anatomic site. In normal subjects the mean count ratios in the right atrium, ventricle and lungs were 0.24 on average. In atrial septal defects, the count ratios were high in the right atrium, ventricle and lungs, whereas in ventricular septal defects the count ratios were higher only in the right ventricle and lungs. Patent ductus arteriosus showed normal count ratios in the heart but high count ratios were obtained in the lungs. Thus, this count ratios method could be separated normal from those with intracardiac or extracardiac shunts, and moreover, with this method the localization of the shunt level was possible in LRCS. Another method that could differentiate the intracardiac shunts from extracardiac shunts was measuring QP/QS in the left and right lungs. In patent ductus arteriosus, the left lung QP/QS was higher than those of the right lung, whereas in atrial septal defects and ventricular septal defects QP/ QS ratios were equal in both lungs. From this study, it was found that by measuring QP/QS separately in the lungs

  3. Analysis of RIA standard curve by log-logistic and cubic log-logit models

    Yamada, Hideo; Kuroda, Akira; Yatabe, Tami; Inaba, Taeko; Chiba, Kazuo

    1981-01-01

    In order to improve goodness-of-fit in RIA standard analysis, programs for computing log-logistic and cubic log-logit were written in BASIC using personal computer P-6060 (Olivetti). Iterative least square method of Taylor series was applied for non-linear estimation of logistic and log-logistic. Hear ''log-logistic'' represents Y = (a - d)/(1 + (log(X)/c)sup(b)) + d As weights either 1, 1/var(Y) or 1/σ 2 were used in logistic or log-logistic and either Y 2 (1 - Y) 2 , Y 2 (1 - Y) 2 /var(Y), or Y 2 (1 - Y) 2 /σ 2 were used in quadratic or cubic log-logit. The term var(Y) represents squares of pure error and σ 2 represents estimated variance calculated using a following equation log(σ 2 + 1) = log(A) + J log(y). As indicators for goodness-of-fit, MSL/S sub(e)sup(2), CMD% and WRV (see text) were used. Better regression was obtained in case of alpha-fetoprotein by log-logistic than by logistic. Cortisol standard curve was much better fitted with cubic log-logit than quadratic log-logit. Predicted precision of AFP standard curve was below 5% in log-logistic in stead of 8% in logistic analysis. Predicted precision obtained using cubic log-logit was about five times lower than that with quadratic log-logit. Importance of selecting good models in RIA data processing was stressed in conjunction with intrinsic precision of radioimmunoassay system indicated by predicted precision. (author)

  4. Experience curve analysis on South Korean nuclear technology and comparative analysis with South Korean renewable technologies

    Kim, Dong Wook; Chang, Hyun Joon

    2012-01-01

    Increasing awareness on environmental damage and climate change has induced many nations to engage in green growth. South Korea, as one of the largest consumers of energy, is no exception and has shown its determination to pursue green growth in the future. In order to do so, South Korea plans to substitute fossil fuel with alternative sources in electricity generation. However, the key constraint to green growth is the high cost faced by renewable electricity generation. Fortunately, nuclear energy can serve as an economic alternative to fossil fuel. To achieve CO 2 emission reduction and faster economic growth, it is wise to analyze prospects of alternatives using experience curve framework. The results and industry background are consistent for nuclear technology, and the results suggest that nuclear should serve as the main substitute. Consideration of policy risk inherent in renewable also strengthens the argument. Renewable technologies, on the other hand, showed overstated learning capacity that is partially inconsistent with technological background. Nevertheless, the renewable (photovoltaic and fuel cell) should help nuclear marginally in substituting fossil fuel in South Korea's Electricity Generation. - Highlights: ► Progress ratios of renewable energy show great prospect. ► The policy risk is inherent in renewable and may overestimate its prospect. ► Nuclear sources are economic and less affected by policy risk. ► Fuel cell and photovoltaic should help nuclear marginally in green growth.

  5. Evaluation of indicator dilution process in X-ray angiographic images deteriorated by factors of technical origin

    Dernalowicz, J.; Goszczynska, H.; Mazur, P.

    1996-01-01

    Different sources of error in X-rays angiographic images have been discussed. Some kind of error which considerably influences densitometric analysis of time sequences of images - the fluctuation of image intensity during coronarography screening - has been emphasized and discussed in details. Three practical solutions of how to correct (compensate) such error have been proposed and described. (author)

  6. Analysis of Surface Plasmon Resonance Curves with a Novel Sigmoid-Asymmetric Fitting Algorithm

    Daeho Jang

    2015-09-01

    Full Text Available The present study introduces a novel curve-fitting algorithm for surface plasmon resonance (SPR curves using a self-constructed, wedge-shaped beam type angular interrogation SPR spectroscopy technique. Previous fitting approaches such as asymmetric and polynomial equations are still unsatisfactory for analyzing full SPR curves and their use is limited to determining the resonance angle. In the present study, we developed a sigmoid-asymmetric equation that provides excellent curve-fitting for the whole SPR curve over a range of incident angles, including regions of the critical angle and resonance angle. Regardless of the bulk fluid type (i.e., water and air, the present sigmoid-asymmetric fitting exhibited nearly perfect matching with a full SPR curve, whereas the asymmetric and polynomial curve fitting methods did not. Because the present curve-fitting sigmoid-asymmetric equation can determine the critical angle as well as the resonance angle, the undesired effect caused by the bulk fluid refractive index was excluded by subtracting the critical angle from the resonance angle in real time. In conclusion, the proposed sigmoid-asymmetric curve-fitting algorithm for SPR curves is widely applicable to various SPR measurements, while excluding the effect of bulk fluids on the sensing layer.

  7. The value of regional wall motion abnormalities on gated mycardiac perfusion imaging in perfusion imaging in predicting angiographic stenoses of coronary artery

    Yao Lixin; Liu Binbin

    2007-01-01

    Objective: To determine the possible level of angiographic stenoses of coronary artery at which reversible regional wall motion abnormalities (RWMA) are present on 99m Tc-sestamibi ( 99m Tc-MIBI)-gated myocardial perfusion imaging (MPI). Methods: ninty patients undergoing coronary angiography MPI within two weeks were recruited. A five grades and nine segments marking system was introduced to assess the RWMA and thickening of left ventricles. Results: The sensitivity of reversible RWMA for detecting ≥75% angiographic stenoses was 64%,with a specificity of 95% and positive predictive value of 97%. The presence of reversible RWMA was able to stratify patients with severe angiographic stenoses of 75% or more from those less than 75% with high positive predictive value. A good correlation was noted between the presence of reversible RWMA and the coronary artery jeopardy score. Multivariate analysis showed that the post-stress RWMA and reversible RWMA scores and positive dipyridamole-stress exercise electrocardiogram(ECG) were significant predictors of angiographic severity. Conclusions: Reversible RWMA, as shown by dipyridamole stress 99m Tc-MIBI MPI, is a significant predictor of angiographic disease with very high specificity and adds incremental value to MPI for the assessment of angiographic severity. (authors)

  8. Application of decline curve analysis to estimate recovery factors for carbon dioxide enhanced oil recovery

    Jahediesfanjani, Hossein

    2017-07-17

    IntroductionIn the decline curve analysis (DCA) method of estimating recoverable hydrocarbon volumes, the analyst uses historical production data from a well, lease, group of wells (or pattern), or reservoir and plots production rates against time or cumu­lative production for the analysis. The DCA of an individual well is founded on the same basis as the fluid-flow principles that are used for pressure-transient analysis of a single well in a reservoir domain and therefore can provide scientifically reasonable and accurate results. However, when used for a group of wells, a lease, or a reservoir, the DCA becomes more of an empirical method. Plots from the DCA reflect the reservoir response to the oil withdrawal (or production) under the prevailing operating and reservoir conditions, and they continue to be good tools for estimating recoverable hydrocarbon volumes and future production rates. For predicting the total recov­erable hydrocarbon volume, the DCA results can help the analyst to evaluate the reservoir performance under any of the three phases of reservoir productive life—primary, secondary (waterflood), or tertiary (enhanced oil recovery) phases—so long as the historical production data are sufficient to establish decline trends at the end of the three phases.

  9. Role of Melt Curve Analysis in Interpretation of Nutrigenomics' MicroRNA Expression Data.

    Ahmed, Farid E; Gouda, Mostafa M; Hussein, Laila A; Ahmed, Nancy C; Vos, Paul W; Mohammad, Mahmoud A

    2017-01-01

    This article illustrates the importance of melt curve analysis (MCA) in interpretation of mild nutrogenomic micro(mi)RNA expression data, by measuring the magnitude of the expression of key miRNA molecules in stool of healthy human adults as molecular markers, following the intake of Pomegranate juice (PGJ), functional fermented sobya (FS), rich in potential probiotic lactobacilli, or their combination. Total small RNA was isolated from stool of 25 volunteers before and following a three-week dietary intervention trial. Expression of 88 miRNA genes was evaluated using Qiagen's 96 well plate RT 2 miRNA qPCR arrays. Employing parallel coordinates plots, there was no observed significant separation for the gene expression (Cq) values, using Roche 480® PCR LightCycler instrument used in this study, and none of the miRNAs showed significant statistical expression after controlling for the false discovery rate. On the other hand, melting temperature profiles produced during PCR amplification run, found seven significant genes (miR-184, miR-203, miR-373, miR-124, miR-96, miR-373 and miR-301a), which separated candidate miRNAs that could function as novel molecular markers of relevance to oxidative stress and immunoglobulin function, for the intake of polyphenol (PP)-rich, functional fermented foods rich in lactobacilli (FS), or their combination. We elaborate on these data, and present a detailed review on use of melt curves for analyzing nutigenomic miRNA expression data, which initially appear to show no significant expressions, but are actually more subtle than this simplistic view, necessitating the understanding of the role of MCA for a comprehensive understanding of what the collective expression and MCA data collectively imply. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  10. The prevalence and clinical profile of angiographic coronary ectasia

    Sultana, R.; Ishaq, M.; Samad, A.

    2011-01-01

    To determine the incidence of Coronary Artery Ectasia (CAE) at our teaching hospital to describe the patients and angiographic characteristics. Methods: A retrospective analysis was conducted on all coronary angiograms performed at the catheterization laboratory of Karachi Institute of Heart Diseases, a tertiary care center, between the period of August 2006 and August 2008. A one year follow up was performed to look for primary and secondary endpoints. Data were collected from catheterization films, and medical records. Results: Five thousand coronary angiograms were performed during the period of of the study. A total of 140 (2.8%) angiograms showed coronary ectasia of both mixed and pure types. Pure ectasia with no coronary obstructive lesions was seen in 75 (1.5%). The left anterior descending artery (LAD) was the most commonly affected vessel (63%) followed by the right coronary artery (RCA) 25% and 10% patients had circumflex artery involvement. The primary composite endpoint showed 6 (4.2%) patients with non-ST elevation MI, 5 (3.6%) with ST elevation inferior wall myocardial infarction, 70 (50%) with unstable angina and 2 (1.4%) deaths due to pulmonary oedema. Secondary endpoints showed 50% of the patients still complaining of chest pain. Conclusion: Prevalence of Coronary ectasia in the population presenting to KIHD during the study period was 1.5%. Majority of patients were males, associated with dyslipidaemia, hypertension and smoking. CAE was associated with obstructive coronary artery disease in about 80% of cases. LAD was the most commonly affected vessel. (author)

  11. High-throughput gender identification of penguin species using melting curve analysis.

    Tseng, Chao-Neng; Chang, Yung-Ting; Chiu, Hui-Tzu; Chou, Yii-Cheng; Huang, Hurng-Wern; Cheng, Chien-Chung; Liao, Ming-Hui; Chang, Hsueh-Wei

    2014-04-03

    Most species of penguins are sexual monomorphic and therefore it is difficult to visually identify their genders for monitoring population stability in terms of sex ratio analysis. In this study, we evaluated the suitability using melting curve analysis (MCA) for high-throughput gender identification of penguins. Preliminary test indicated that the Griffiths's P2/P8 primers were not suitable for MCA analysis. Based on sequence alignment of Chromo-Helicase-DNA binding protein (CHD)-W and CHD-Z genes from four species of penguins (Pygoscelis papua, Aptenodytes patagonicus, Spheniscus magellanicus, and Eudyptes chrysocome), we redesigned forward primers for the CHD-W/CHD-Z-common region (PGU-ZW2) and the CHD-W-specific region (PGU-W2) to be used in combination with the reverse Griffiths's P2 primer. When tested with P. papua samples, PCR using P2/PGU-ZW2 and P2/PGU-W2 primer sets generated two amplicons of 148- and 356-bp, respectively, which were easily resolved in 1.5% agarose gels. MCA analysis indicated the melting temperature (Tm) values for P2/PGU-ZW2 and P2/PGU-W2 amplicons of P. papua samples were 79.75°C-80.5°C and 81.0°C-81.5°C, respectively. Females displayed both ZW-common and W-specific Tm peaks, whereas male was positive only for ZW-common peak. Taken together, our redesigned primers coupled with MCA analysis allows precise high throughput gender identification for P. papua, and potentially for other penguin species such as A. patagonicus, S. magellanicus, and E. chrysocome as well.

  12. Analysis of possibilities of early diagnostics criteria for Parkinson's disease based on analysis of the input-output curve

    Janković Marko

    2013-01-01

    Full Text Available In this paper, we analyze the possibilities of the diagnosis of Parkinson's disease at an early stage, based on characteristics of the input-output curve. The input-output (IO curve was analyzed in two ways: we analyzed the gain of the curve for low-level transcranial stimulation and we analyzed the overall 'quality' of the IO curve. The 'quality' of the curve calculation is based on basic concepts from quantum mechanics and calculation of Tsallis entropy.

  13. Fitness of the analysis method of magnesium in drinking water using atomic absorption with quadratic calibration curve

    Perez-Lopez, Esteban

    2014-01-01

    The quantitative chemical analysis has been importance in research. Also, aspects like: quality control, sales of services and other areas of interest. Some instrumental analysis methods for quantification with linear calibration curve have presented limitations, because the short liner dynamic ranges of the analyte, or sometimes, by limiting the technique itself. The need has been to investigate a little more about the convenience of using quadratic calibration curves for analytical quantification, with which it has seeked demonstrate that has been a valid calculation model for chemical analysis instruments. An analysis base method is used on the technique of atomic absorption spectroscopy and in particular a determination of magnesium in a drinking water sample of the Tacares sector North of Grecia. A nonlinear calibration curve was used and specifically a curve with quadratic behavior. The same was compared with the test results obtained for the equal analysis with a linear calibration curve. The results have showed that the methodology has been valid for the determination referred with all confidence, since the concentrations have been very similar and, according to the used hypothesis testing, can be considered equal. (author) [es

  14. THE XMM-NEWTON/EPIC X-RAY LIGHT CURVE ANALYSIS OF WR 6

    Ignace, R.; Gayley, K. G.; Hamann, W.-R.; Oskinova, L. M.; Huenemoerder, D. P.; Pollock, A. M. T.; McFall, M.

    2013-01-01

    We obtained four pointings of over 100 ks each of the well-studied Wolf-Rayet star WR 6 with the XMM-Newton satellite. With a first paper emphasizing the results of spectral analysis, this follow-up highlights the X-ray variability clearly detected in all four pointings. However, phased light curves fail to confirm obvious cyclic behavior on the well-established 3.766 day period widely found at longer wavelengths. The data are of such quality that we were able to conduct a search for event clustering in the arrival times of X-ray photons. However, we fail to detect any such clustering. One possibility is that X-rays are generated in a stationary shock structure. In this context we favor a corotating interaction region (CIR) and present a phenomenological model for X-rays from a CIR structure. We show that a CIR has the potential to account simultaneously for the X-ray variability and constraints provided by the spectral analysis. Ultimately, the viability of the CIR model will require both intermittent long-term X-ray monitoring of WR 6 and better physical models of CIR X-ray production at large radii in stellar winds

  15. THE XMM-NEWTON/EPIC X-RAY LIGHT CURVE ANALYSIS OF WR 6

    Ignace, R. [Department of Physics and Astronomy, East Tennessee State University, Johnson City, TN 37663 (United States); Gayley, K. G. [Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52245 (United States); Hamann, W.-R.; Oskinova, L. M. [Institute for Physics and Astronomy, University Potsdam, D-14476 Potsdam (Germany); Huenemoerder, D. P. [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, 70 Vassar Street, Cambridge, MA 02139 (United States); Pollock, A. M. T. [European Space Agency XMM-Newton Science Operations Centre, European Space Astronomy Centre, Apartado 78, Villanueva de la Cañada, E-28691 Madrid (Spain); McFall, M., E-mail: ignace@etsu.edu [Department of Physics, 191 W. Woodruff Avenue, Ohio State University, Columbus, OH 43210 (United States)

    2013-09-20

    We obtained four pointings of over 100 ks each of the well-studied Wolf-Rayet star WR 6 with the XMM-Newton satellite. With a first paper emphasizing the results of spectral analysis, this follow-up highlights the X-ray variability clearly detected in all four pointings. However, phased light curves fail to confirm obvious cyclic behavior on the well-established 3.766 day period widely found at longer wavelengths. The data are of such quality that we were able to conduct a search for event clustering in the arrival times of X-ray photons. However, we fail to detect any such clustering. One possibility is that X-rays are generated in a stationary shock structure. In this context we favor a corotating interaction region (CIR) and present a phenomenological model for X-rays from a CIR structure. We show that a CIR has the potential to account simultaneously for the X-ray variability and constraints provided by the spectral analysis. Ultimately, the viability of the CIR model will require both intermittent long-term X-ray monitoring of WR 6 and better physical models of CIR X-ray production at large radii in stellar winds.

  16. Reliability assessment of a manual-based procedure towards learning curve modeling and fmea analysis

    Gustavo Rech

    2013-03-01

    Full Text Available Separation procedures in drug Distribution Centers (DC are manual-based activities prone to failures such as shipping exchanged, expired or broken drugs to the customer. Two interventions seem as promising in improving the reliability in the separation procedure: (i selection and allocation of appropriate operators to the procedure, and (ii analysis of potential failure modes incurred by selected operators. This article integrates Learning Curves (LC and FMEA (Failure Mode and Effect Analysis aimed at reducing the occurrence of failures in the manual separation of a drug DC. LCs parameters enable generating an index to identify the recommended operators to perform the procedures. The FMEA is then applied to the separation procedure carried out by the selected operators in order to identify failure modes. It also deployed the traditional FMEA severity index into two sub-indexes related to financial issues and damage to company´s image in order to characterize failures severity. When applied to a drug DC, the proposed method significantly reduced the frequency and severity of failures in the separation procedure.

  17. [Multiple linear regression and ROC curve analysis of the factors of lumbar spine bone mineral density].

    Zhang, Xiaodong; Zhao, Yinxia; Hu, Shaoyong; Hao, Shuai; Yan, Jiewen; Zhang, Lingyan; Zhao, Jing; Li, Shaolin

    2015-09-01

    To investigate the correlation between the lumbar vertebra bone mineral density (BMD) and age, gender, height, weight, body mass index, waistline, hipline, bone marrow and abdomen fat, and to explore the key factor affecting the BMD. A total of 72 cases were randomly recruited. All the subjects underwent a spectroscopic examination of the third lumber vertebra with single-voxel method in 1.5T MR. Lipid fractions (FF%) were measured. Quantitative CT were also performed to get the BMD of L3 and the corresponding abdomen subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). The statistical analysis were performed by SPSS 19.0. Multiple linear regression showed except the age and FF% showed significant difference (P0.05). The correlation of age and FF% with BMD was statistically negatively significant (r=-0.830, -0.521, P<0.05). The ROC curve analysis showed that the sensitivety and specificity of predicting osteoporosis were 81.8% and 86.9%, with a threshold of 58.5 years old. And it showed that the sensitivety and specificity of predicting osteoporosis were 90.9% and 55.7%, with a threshold of 52.8% for FF%. The lumbar vertebra BMD was significantly and negatively correlated with age and bone marrow FF%, but it was not significantly correlated with gender, height, weight, BMI, waistline, hipline, SAT and VAT. And age was the critical factor.

  18. STRESS - STRAIN CURVE ANALYSIS OF WOVEN FABRICS MAD E FROM COMBED YARNS TYPE WOOL

    VÎLCU Adrian

    2014-05-01

    Full Text Available The paper analyses the tensile behavior of woven fabrics made from 45%Wool + 55% PES used for garments. Analysis of fabric behavior during wearing has shown that these are submitted to simple and repeated uni-axial or bi-axial tensile strains. The level of these strains is often within the elastic limit, rarely going over yielding. Therefore the designer must be able to evaluate the mechanical behavior of such fabrics in order to control the fabric behavior in the garment. This evaluation is carried out based on the tensile testing, using certain indexes specific to the stress-strain curve. The paper considers an experimental matrix based on woven fabrics of different yarn counts, different or equal yarn count for warp and weft systems and different structures. The fabrics were tested using a testing machine and the results were then compared in order to determine the fabrics’ tensile behavior and the factors of influence that affect it.From the point of view of tensile testing, the woven materials having twill weave are preferable because this type of structure is characterized by higher durability and better yarn stability in the fabric. In practice, the woven material must exhibit an optimum behavior to repeated strains, flexions and abrasions during wearing process. The analysis of fabrics tensile properties studied by investigation of stress-strain diagrams reveals that the main factors influencing the tensile strength are: yarns fineness, technological density of those two systems of yarns and the weaving type.

  19. Modeling and regression analysis of semiochemical dose-response curves of insect antennal reception and behavior

    Dose-response curves with semiochemicals are reported in many articles in insect chemical ecology regarding neurophysiology and behavioral bioassays. Most such curves are shown in figures where the x-axis has order of magnitude increases in dosages versus responses on the y-axis represented by point...

  20. Measurement of activated rCBF by the 133Xe inhalation technique: a comparison of total versus partial curve analysis

    Leli, D.A.; Katholi, C.R.; Hazelrig, J.B.; Falgout, J.C.; Hannay, H.J.; Wilson, E.M.; Wills, E.L.; Halsey, J.H. Jr.

    1985-01-01

    An initial assessment of the differential sensitivity of total versus partial curve analysis in estimating task related focal changes in cortical blood flow measured by the 133 Xe inhalation technique was accomplished by comparing the patterns during the performance of two sensorimotor tasks by normal subjects. The validity of these patterns was evaluated by comparing them to the activation patterns expected from activation studies with the intra-arterial technique and the patterns expected from neuropsychological research literature. Subjects were 10 young adult nonsmoking healthy male volunteers. They were administered two tasks having identical sensory and cognitive components but different response requirements (oral versus manual). The regional activation patterns produced by the tasks varied with the method of curve analysis. The activation produced by the two tasks was very similar to that predicted from the research literature only for total curve analysis. To the extent that the predictions are correct, these data suggest that the 133 Xe inhalation technique is more sensitive to regional flow changes when flow parameters are estimated from the total head curve. The utility of the total head curve analysis will be strengthened if similar sensitivity is demonstrated in future studies assessing normal subjects and patients with neurological and psychiatric disorders

  1. Intracranial meningeal masson's hemangioma: CT and angiographic features

    Chang, Kee Hyun; Chi, Je Gen; Han, Man Chung; Cho, Byung Kyu; Kim, Hyun Jip

    1985-01-01

    Masson's hemangioma is a rare benign vascular condition with a papillary intravascular endothelial proliferation which may appear either as a primary form as a secondary form in a pre-existing vascular process. CT and angiographic features of 2 cases with Masson's hemangioma were presented. Both of them were located extra-axially in the posterior fossa. CT findings were not specific in both cases; One showed homogeneously enhancing mass, simulating meningioma. And the other demonstrated a multiocular rim enhancing mass. However, the angiographic features were rather characteristic; Both cases showed persistent vascular poolings of contrast media which were supplied form the meningeal vessels. Angiographic differential diagnosis of similar lesions in the posterior fossa is discussed

  2. Thermo-Electro-Mechanical Analysis of a Curved Functionally Graded Piezoelectric Actuator with Sandwich Structure

    Liying Jiang

    2011-12-01

    Full Text Available In this work, the problem of a curved functionally graded piezoelectric (FGP actuator with sandwich structure under electrical and thermal loads is investigated. The middle layer in the sandwich structure is functionally graded with the piezoelectric coefficient g31 varying continuously along the radial direction of the curved actuator. Based on the theory of linear piezoelectricity, analytical solutions are obtained by using Airy stress function to examine the effects of material gradient and heat conduction on the performance of the curved actuator. It is found that the material gradient and thermal load have significant influence on the electroelastic fields and the mechanical response of the curved FGP actuator. Without the sacrifice of actuation deflection, smaller internal stresses are generated by using the sandwich actuator with functionally graded piezoelectric layer instead of the conventional bimorph actuator. This work is very helpful for the design and application of curved piezoelectric actuators under thermal environment.

  3. Thermo-Electro-Mechanical Analysis of a Curved Functionally Graded Piezoelectric Actuator with Sandwich Structure.

    Yan, Zhi; Zaman, Mostafa; Jiang, Liying

    2011-12-12

    In this work, the problem of a curved functionally graded piezoelectric (FGP) actuator with sandwich structure under electrical and thermal loads is investigated. The middle layer in the sandwich structure is functionally graded with the piezoelectric coefficient g 31 varying continuously along the radial direction of the curved actuator. Based on the theory of linear piezoelectricity, analytical solutions are obtained by using Airy stress function to examine the effects of material gradient and heat conduction on the performance of the curved actuator. It is found that the material gradient and thermal load have significant influence on the electroelastic fields and the mechanical response of the curved FGP actuator. Without the sacrifice of actuation deflection, smaller internal stresses are generated by using the sandwich actuator with functionally graded piezoelectric layer instead of the conventional bimorph actuator. This work is very helpful for the design and application of curved piezoelectric actuators under thermal environment.

  4. A Literature-Based Analysis of the Learning Curves of Laparoscopic Radical Prostatectomy

    Daniel W. Good

    2014-05-01

    Full Text Available There is a trend for the increased adoption of minimally invasive techniques of radical prostatectomy (RP – laparoscopic (LRP and robotic assisted (RARP – from the traditional open radical retropubic prostatectomy (ORP, popularised by Partin et al. Recently there has been a dramatic expansion in the rates of RARP being performed, and there have been many early reports postulating that the learning curve for RARP is shorter than for LRP. The aim of this study was to review the literature and analyse the length of the LRP learning curves for the various outcome measures: perioperative, oncologic, and functional outcomes. A broad search of the literature was performed in November 2013 using the PubMed database. Only studies of real patients and those from 2004 until 2013 were included; those on simulators were excluded. In total, 239 studies were identified after which 13 were included. The learning curve is a heterogeneous entity, depending entirely on the criteria used to define it. There is evidence of multiple learning curves; however the length of these is dependent on the definitions used by the authors. Few studies use the more rigorous definition of plateauing of the curve. Perioperative learning curve takes approximately 150-200 cases to plateau, oncologic curve approximately 200 cases, and the functional learning curve up to 700 cases to plateau (700 for potency, 200 cases for continence. In this review, we have analysed the literature with respect to the learning curve for LRP. It is clear that the learning curve is long. This necessitates centralising LRP to high volume centres such that surgeons, trainees, and patients are able to utilise the benefits of LRP.

  5. Periodicity Analysis of X-ray Light Curves of SS 433

    Wang, Jun-yi; Lu, Xiang-long; Zhao, Qiu-wen; Dong, Dian-qiao; Lao, Bao-qiang; Lu, Yang; Wei, Yan-heng; Wu, Xiao-cong; An, Tao

    2017-01-01

    SS 433 is sofar the unique X-ray binary that has the simultaneously detected orbital period, super-orbital period, and nutation period, as well as a bidirectional spiral jet. The study on its X-ray light variability is helpful for understanding the dynamic process of the system, and the correlations between the different wavebands. In this paper, two time-series analysis techniques, i.e., the Lomb-Scargle periodogram and weighted wavelet Z-transform, are employed to search for the periods in the Swift/BAT (Burst Alert Telescope) (15-50 keV) and RXTE/ASM (Rose X-ray Timing Explorer/All Sky Monitor) (1.5-3, 3- 4, and 5-12 keV) light curves of SS 433, and the Monte Carlo simulation is performed for the obtained periodical components. For the 15-50 keV energy band, five significant periodical components are detected, which are P1(∼6.29 d), P2 (∼6.54 d), P3 (∼13.08 d), P4 (∼81.50 d), and P5 (∼162.30 d). For the 3-5 and 5-12 keV energy bands, the periodical components P3 (∼13 d) and P5 (∼162 d) are detected in both energy bands. However, for the 1.5-3 keV energy band, no significant periodic signal is detected. P5 is the strongest periodic signal in the power spectrum for all the energy bands of 3-5, 5-12, and 15-50 keV, and it is consistent with the previous result obtained from the study of optical light curves. Furthermore, in combination with the radio spiral jet of SS 433, it is suggested that the X-ray and optical variability of P5 (∼162 d) is probably related to the precession of its relativistic jet. The high correlation between the X-ray and optical light curves may also imply that the X-ray and optical radiations are of the same physical origin. P3 shows a good agreement with the orbital period (∼13.07 d) obtained by the previous study, and P2 and P4 are respectively the high-frequency harmonics of P3 and P5. P1 is detected only in the power spectrum of the 15-50 keV energy band, and it is consistent with the nutation period of the system. As

  6. Qualitative and quantitative analysis of complex temperature-programmed desorption data by multivariate curve resolution

    Rodríguez-Reyes, Juan Carlos F.; Teplyakov, Andrew V.; Brown, Steven D.

    2010-10-01

    The substantial amount of information carried in temperature-programmed desorption (TPD) experiments is often difficult to mine due to the occurrence of competing reaction pathways that produce compounds with similar mass spectrometric features. Multivariate curve resolution (MCR) is introduced as a tool capable of overcoming this problem by mathematically detecting spectral variations and correlations between several m/z traces, which is later translated into the extraction of the cracking pattern and the desorption profile for each desorbate. Different from the elegant (though complex) methods currently available to analyze TPD data, MCR analysis is applicable even when no information regarding the specific surface reaction/desorption process or the nature of the desorbing species is available. However, when available, any information can be used as constraints that guide the outcome, increasing the accuracy of the resolution. This approach is especially valuable when the compounds desorbing are different from what would be expected based on a chemical intuition, when the cracking pattern of the model test compound is difficult or impossible to obtain (because it could be unstable or very rare), and when knowing major components desorbing from the surface could in more traditional methods actually bias the quantification of minor components. The enhanced level of understanding of thermal processes achieved through MCR analysis is demonstrated by analyzing three phenomena: i) the cryogenic desorption of vinyltrimethylsilane from silicon, an introductory system where the known multilayer and monolayer components are resolved; ii) acrolein hydrogenation on a bimetallic Pt-Ni-Pt catalyst, where a rapid identification of hydrogenated products as well as other desorbing species is achieved, and iii) the thermal reaction of Ti[N(CH 3) 2] 4 on Si(100), where the products of surface decomposition are identified and an estimation of the surface composition after the

  7. The role of Soil Water Retention Curve in slope stability analysis in unsaturated and heterogeneous soils.

    Antinoro, Chiara; Arnone, Elisa; Noto, Leonardo V.

    2015-04-01

    The mechanisms of rainwater infiltration causing slope instability had been analyzed and reviewed in many scientific works. Rainwater infiltration into unsaturated soil increases the degree of saturation, hence affecting the shear strength properties and thus the probability of slope failure. It has been widely proved that the shear strength properties change with the soil water suction in unsaturated soils; therefore, the accuracy to predict the relationship between soil water content and soil water suction, parameterized by the soil-water characteristic curve, has significant effects on the slope stability analysis. The aim of this study is to investigate how the characterization of SWRC of differently structured unsaturated soils affects the slope stability on a simple infinite slope. In particular, the unimodal and bimodal distributions of the soil pore size were compared. Samples of 40 soils, highly different in terms of structure and texture, were collected and used to calibrate two bimodal SWRCs, i.e. Ross and Smettem (1993) and Dexter et al., (2008). The traditional unimodal van Genuchten (1980) model was also applied for comparison. Slope stability analysis was conducted in terms of Factor of Safety (FS) by applying the infinite slope model for unsaturated soils. In the used formulation, the contribution of the suction effect is tuned by a parameter 'chi' in a rate proportional to the saturation conditions. Different parameterizations of this term were also compared and analyzed. Results indicated that all three SWRC models showed good overall performance in fitting the sperimental SWRCs. Both the RS and DE models described adequately the water retention data for soils with a bimodal behavior confirmed from the analysis of pore size distribution, but the best performance was obtained by DE model confirmed. In terms of FS, the tree models showed very similar results as soil moisture approached to the saturated condition; however, within the residual zone

  8. Effect of intrinsic motivation on affective responses during and after exercise: latent curve model analysis.

    Shin, Myoungjin; Kim, Inwoo; Kwon, Sungho

    2014-12-01

    Understanding the relationship between affect and exercise is helpful in predicting human behavior with respect to exercise participation. The goals of the present study were to investigate individual differences in affective response during and after exercise and to identify the role of intrinsic motivation in affective changes. 30 active male college students (M age = 21.4 yr.) who regularly participated in sports activities volunteered to answer a questionnaire measuring intrinsic motivation toward running activities and performed a 20-min. straight running protocol at heavy intensity (about 70% of VO2max). Participants' affective responses were measured every 5 min. from the beginning of the run to 10 min. after completing the run. Latent curve model analysis indicated that individuals experienced different changes in affective state during exercise, moderated by intrinsic motivation. Higher intrinsic motivation was associated with more positive affect during exercise. There were no significant individual differences in the positive tendency of the participants' affective responses after exercise over time. Intrinsic motivation seems to facilitate positive feelings during exercise and encourages participation in exercise.

  9. The application of latent curve analysis to testing developmental theories in intervention research.

    Curran, P J; Muthén, B O

    1999-08-01

    The effectiveness of a prevention or intervention program has traditionally been assessed using time-specific comparisons of mean levels between the treatment and the control groups. However, many times the behavior targeted by the intervention is naturally developing over time, and the goal of the treatment is to alter this natural or normative developmental trajectory. Examining time-specific mean levels can be both limiting and potentially misleading when the behavior of interest is developing systematically over time. It is argued here that there are both theoretical and statistical advantages associated with recasting intervention treatment effects in terms of normative and altered developmental trajectories. The recently developed technique of latent curve (LC) analysis is reviewed and extended to a true experimental design setting in which subjects are randomly assigned to a treatment intervention or a control condition. LC models are applied to both artificially generated and real intervention data sets to evaluate the efficacy of an intervention program. Not only do the LC models provide a more comprehensive understanding of the treatment and control group developmental processes compared to more traditional fixed-effects models, but LC models have greater statistical power to detect a given treatment effect. Finally, the LC models are modified to allow for the computation of specific power estimates under a variety of conditions and assumptions that can provide much needed information for the planning and design of more powerful but cost-efficient intervention programs for the future.

  10. M DWARFS IN SLOAN DIGITAL SKY SURVEY STRIPE 82: PHOTOMETRIC LIGHT CURVES AND FLARE RATE ANALYSIS

    Kowalski, Adam F.; Hawley, Suzanne L.; Hilton, Eric J.; Becker, Andrew C.; Sesar, Branimir; West, Andrew A.; Bochanski, John J.

    2009-01-01

    We present a flare rate analysis of 50,130 M dwarf light curves in Sloan Digital Sky Survey Stripe 82. We identified 271 flares using a customized variability index to search ∼2.5 million photometric observations for flux increases in the u and g bands. Every image of a flaring observation was examined by eye and with a point-spread function-matching and image subtraction tool to guard against false positives. Flaring is found to be strongly correlated with the appearance of Hα in emission in the quiet spectrum. Of the 99 flare stars that have spectra, we classify eight as relatively inactive. The flaring fraction is found to increase strongly in stars with redder colors during quiescence, which can be attributed to the increasing flare visibility and increasing active fraction for redder stars. The flaring fraction is strongly correlated with |Z| distance such that most stars that flare are within 300 pc of the Galactic plane. We derive flare u-band luminosities and find that the most luminous flares occur on the earlier-type m dwarfs. Our best estimate of the lower limit on the flaring rate (averaged over Stripe 82) for flares with Δu ≥ 0.7 mag on stars with u -1 deg -2 but can vary significantly with the line of sight.

  11. Left ventricular time volume curve analysis in the detection of limited ischaemic heart disease

    Liechtenstein, M.; Blanchett, W.; Andrews, J.; Hunt, D.

    1982-01-01

    The aim of the study was to determine whether limited coronary artery disease (CAD) could be accurately detected using the Cardiac Gated Blood Pool (CGBP) scan with exercise. Regional left ventricular time volume curves (RLTVD) were generated from 52 studies (46 patients: 22 normals, 24 abnormals). The parameters assessed both globally and regionally and at rest (R) and exercise (Ex) were: (1) the ejection fraction (EF) (2) the change in ejection fraction from R to Ex (δEF) (3) an early contraction index (ECI) (4) a maximal emptying index (DR) and (5) a maximal refilling index (AR). After careful analysis of these parameters it was decided that our diagnostic criteria would rely on the following: (1) the EF at R and Ex (2) the δ EF (3) the ECI at Ex (4) the AR at Ex This study showed that both the sensitivity and the specificity of the CGBP scan can be improved considerably with the inclusion of RLTVC from the levels obtained when the EF parameters alone are considered. It is possible with this technique to accurately diagnose limited CAD. (Author)

  12. Cognitive Vulnerabilities and Depression in Young Adults: An ROC Curves Analysis.

    Balsamo, Michela; Imperatori, Claudio; Sergi, Maria Rita; Belvederi Murri, Martino; Continisio, Massimo; Tamburello, Antonino; Innamorati, Marco; Saggino, Aristide

    2013-01-01

    Objectives and Methods. The aim of the present study was to evaluate, by means of receiver operating characteristic (ROC) curves, whether cognitive vulnerabilities (CV), as measured by three well-known instruments (the Beck Hopelessness Scale, BHS; the Life Orientation Test-Revised, LOT-R; and the Attitudes Toward Self-Revised, ATS-R), independently discriminate between subjects with different severities of depression. Participants were 467 young adults (336 females and 131 males), recruited from the general population. The subjects were also administered the Beck Depression Inventory-II (BDI-II). Results. Four first-order (BHS Optimism/Low Standard; BHS Pessimism; Generalized Self-Criticism; and LOT Optimism) and two higher-order factors (Pessimism/Negative Attitudes Toward Self, Optimism) were extracted using Principal Axis Factoring analysis. Although all first-order and second-order factors were able to discriminate individuals with different depression severities, the Pessimism factor had the best performance in discriminating individuals with moderate to severe depression from those with lower depression severity. Conclusion. In the screening of young adults at risk of depression, clinicians have to pay particular attention to the expression of pessimism about the future.

  13. Multiplex fluorescence melting curve analysis for mutation detection with dual-labeled, self-quenched probes.

    Qiuying Huang

    2011-04-01

    Full Text Available Probe-based fluorescence melting curve analysis (FMCA is a powerful tool for mutation detection based on melting temperature generated by thermal denaturation of the probe-target hybrid. Nevertheless, the color multiplexing, probe design, and cross-platform compatibility remain to be limited by using existing probe chemistries. We hereby explored two dual-labeled, self-quenched probes, TaqMan and shared-stem molecular beacons, in their ability to conduct FMCA. Both probes could be directly used for FMCA and readily integrated with closed-tube amplicon hybridization under asymmetric PCR conditions. Improved flexibility of FMCA by using these probes was illustrated in three representative applications of FMCA: mutation scanning, mutation identification and mutation genotyping, all of which achieved improved color-multiplexing with easy probe design and versatile probe combination and all were validated with a large number of real clinical samples. The universal cross-platform compatibility of these probes-based FMCA was also demonstrated by a 4-color mutation genotyping assay performed on five different real-time PCR instruments. The dual-labeled, self-quenched probes offered unprecedented combined advantage of enhanced multiplexing, improved flexibility in probe design, and expanded cross-platform compatibility, which would substantially improve FMCA in mutation detection of various applications.

  14. Economic growth and pollutant emissions in Tunisia. An empirical analysis of the environmental Kuznets curve

    Fodha, Mouez [Paris School of Economics and CES, University Paris 1 Pantheon-Sorbonne, Maison des Sciences Economiques, 106-112 Bd de l' Hopital, 75647 Paris (France); Zaghdoud, Oussama [CES, University Paris 1 Pantheon-Sorbonne and Department of Economics, High School of Economic and Commercial Sciences of Tunis, 4 Rue Abou Zakaria El Hafsi, 1089 Montfleury (Tunisia)

    2010-02-15

    This paper investigates the relationship between economic growth and pollutant emissions for a small and open developing country, Tunisia, during the period 1961-2004. The investigation is made on the basis of the environmental Kuznets curve hypothesis, using time series data and cointegration analysis. Carbon dioxide (CO{sub 2}) and sulfur dioxide (SO{sub 2}) are used as the environmental indicators, and GDP as the economic indicator. Our results show that there is a long-run cointegrating relationship between the per capita emissions of two pollutants and the per capita GDP. An inverted U relationship between SO{sub 2} emissions and GDP has been found, with income turning point approximately equals to 1200 (constant 2000 prices) or to 3700 (in PPP, constant 2000 prices). However, a monotonically increasing relationship with GDP is found more appropriate for CO{sub 2} emissions. Furthermore, the causality results show that the relationship between income and pollution in Tunisia is one of unidirectional causality with income causing environmental changes and not vice versa, both in the short-run and long-run. This implies that an emission reduction policies and more investment in pollution abatement expense will not hurt economic growth. It could be a feasible policy tool for Tunisia to achieve its sustainable growth in the long-run. (author)

  15. Economic growth and pollutant emissions in Tunisia: An empirical analysis of the environmental Kuznets curve

    Fodha, Mouez, E-mail: fodha@univ-paris1.f [Paris School of Economics and CES, University Paris 1 Pantheon-Sorbonne, Maison des Sciences Economiques, 106-112 Bd de l' Hopital, 75647 Paris (France); Zaghdoud, Oussama [CES, University Paris 1 Pantheon-Sorbonne and Department of Economics, High School of Economic and Commercial Sciences of Tunis, 4 Rue Abou Zakaria El Hafsi, 1089 Montfleury (Tunisia)

    2010-02-15

    This paper investigates the relationship between economic growth and pollutant emissions for a small and open developing country, Tunisia, during the period 1961-2004. The investigation is made on the basis of the environmental Kuznets curve hypothesis, using time series data and cointegration analysis. Carbon dioxide (CO{sub 2}) and sulfur dioxide (SO{sub 2}) are used as the environmental indicators, and GDP as the economic indicator. Our results show that there is a long-run cointegrating relationship between the per capita emissions of two pollutants and the per capita GDP. An inverted U relationship between SO{sub 2} emissions and GDP has been found, with income turning point approximately equals to $1200 (constant 2000 prices) or to $3700 (in PPP, constant 2000 prices). However, a monotonically increasing relationship with GDP is found more appropriate for CO{sub 2} emissions. Furthermore, the causality results show that the relationship between income and pollution in Tunisia is one of unidirectional causality with income causing environmental changes and not vice versa, both in the short-run and long-run. This implies that an emission reduction policies and more investment in pollution abatement expense will not hurt economic growth. It could be a feasible policy tool for Tunisia to achieve its sustainable growth in the long-run.

  16. On the applicability of numerical image mapping for PIV image analysis near curved interfaces

    Masullo, Alessandro; Theunissen, Raf

    2017-01-01

    This paper scrutinises the general suitability of image mapping for particle image velocimetry (PIV) applications. Image mapping can improve PIV measurement accuracy by eliminating overlap between the PIV interrogation windows and an interface, as illustrated by some examples in the literature. Image mapping transforms the PIV images using a curvilinear interface-fitted mesh prior to performing the PIV cross correlation. However, degrading effects due to particle image deformation and the Jacobian transformation inherent in the mapping along curvilinear grid lines have never been deeply investigated. Here, the implementation of image mapping from mesh generation to image resampling is presented in detail, and related error sources are analysed. Systematic comparison with standard PIV approaches shows that image mapping is effective only in a very limited set of flow conditions and geometries, and depends strongly on a priori knowledge of the boundary shape and streamlines. In particular, with strongly curved geometries or streamlines that are not parallel to the interface, the image-mapping approach is easily outperformed by more traditional image analysis methodologies invoking suitable spatial relocation of the obtained displacement vector. (paper)

  17. Economic growth and pollutant emissions in Tunisia: An empirical analysis of the environmental Kuznets curve

    Fodha, Mouez; Zaghdoud, Oussama

    2010-01-01

    This paper investigates the relationship between economic growth and pollutant emissions for a small and open developing country, Tunisia, during the period 1961-2004. The investigation is made on the basis of the environmental Kuznets curve hypothesis, using time series data and cointegration analysis. Carbon dioxide (CO 2 ) and sulfur dioxide (SO 2 ) are used as the environmental indicators, and GDP as the economic indicator. Our results show that there is a long-run cointegrating relationship between the per capita emissions of two pollutants and the per capita GDP. An inverted U relationship between SO 2 emissions and GDP has been found, with income turning point approximately equals to $1200 (constant 2000 prices) or to $3700 (in PPP, constant 2000 prices). However, a monotonically increasing relationship with GDP is found more appropriate for CO 2 emissions. Furthermore, the causality results show that the relationship between income and pollution in Tunisia is one of unidirectional causality with income causing environmental changes and not vice versa, both in the short-run and long-run. This implies that an emission reduction policies and more investment in pollution abatement expense will not hurt economic growth. It could be a feasible policy tool for Tunisia to achieve its sustainable growth in the long-run.

  18. Biological radiation dose estimation by chromosomal aberrations analysis in human peripheral blood (dose- effect curve)

    Al Achkar, W.

    2002-01-01

    In order to draw a dose-effect curve, blood from eight healthy people were studied. Samples were irradiated in tubes with 0.15-2.5 gray of gamma ray.Irradiated and control samples were incubated for cell cultures. Chromosomal aberrations from 67888 metaphases were scored. Curves from the total number of dicentrics, dicentrics+ rings and total numbers of breaks were drawn. The yield of chromosome aberrations is related to the dose used. These curves give a quick useful estimation of the accidentally radiation exposure. (author)

  19. Simulation and analysis of the transmission properties of curved-straight neutron guide systems

    Copley, J.R.D.; Mildner, D.F.R.

    1992-01-01

    This paper reports that the spatial intensity distribution of neutrons emerging from a curved guide is far from uniform, particularly at short wavelengths, and curved guides are sometimes followed by a straight section of guide to make the intensity distribution more uniform. The behavior of neutrons within curved-straight neutron guide systems is examined using both ray-tracing and analytical approaches to the problem. The intensity distribution within the straight guide tends to wash from one side of the guide to the other. The amplitude of this transverse wave decreases with increasing guide length, and the characteristic length of the wave decreases with increasing neutron wavelength

  20. ANALYSIS OF THE SECONDARY CURVES IN PATIENTS UNDERGOING SELECTIVE ARTHRODESIS LENKE I

    TADEU GERVAZONI DEBOM

    2015-12-01

    Full Text Available Objective : To radiographically evaluate the behavior of the secondary curves in the coronal and sagittal planes in patients with AIS classified as Lenke I, who underwent surgical treatment of selective arthrodesis by posterior approach. Methods : Retrospective study which analyzed 40 patients with AIS, being 33 female. The measurement of the radiographic parameters used followed the recommendations by Cobb. Results : The average correction of the thoracic proximal, primary and lumbar curves was 34.73%, 75.06% and 64.64%, respectively. Conclusion : Surgical treatment by selective arthrodesis in cases of AIS Lenke type I provide correction of compensatory curves in the coronal and maintenance in the sagittal plane.

  1. On the analysis of glycomics mass spectrometry data via the regularized area under the ROC curve

    Lebrilla Carlito B

    2007-12-01

    Full Text Available Abstract Background Novel molecular and statistical methods are in rising demand for disease diagnosis and prognosis with the help of recent advanced biotechnology. High-resolution mass spectrometry (MS is one of those biotechnologies that are highly promising to improve health outcome. Previous literatures have identified some proteomics biomarkers that can distinguish healthy patients from cancer patients using MS data. In this paper, an MS study is demonstrated which uses glycomics to identify ovarian cancer. Glycomics is the study of glycans and glycoproteins. The glycans on the proteins may deviate between a cancer cell and a normal cell and may be visible in the blood. High-resolution MS has been applied to measure relative abundances of potential glycan biomarkers in human serum. Multiple potential glycan biomarkers are measured in MS spectra. With the objection of maximizing the empirical area under the ROC curve (AUC, an analysis method was considered which combines potential glycan biomarkers for the diagnosis of cancer. Results Maximizing the empirical AUC of glycomics MS data is a large-dimensional optimization problem. The technical difficulty is that the empirical AUC function is not continuous. Instead, it is in fact an empirical 0–1 loss function with a large number of linear predictors. An approach was investigated that regularizes the area under the ROC curve while replacing the 0–1 loss function with a smooth surrogate function. The constrained threshold gradient descent regularization algorithm was applied, where the regularization parameters were chosen by the cross-validation method, and the confidence intervals of the regression parameters were estimated by the bootstrap method. The method is called TGDR-AUC algorithm. The properties of the approach were studied through a numerical simulation study, which incorporates the positive values of mass spectrometry data with the correlations between measurements within person

  2. Parametric and quantitative analysis of MR renographic curves for assessing the functional behaviour of the kidney

    Michoux, N.; Montet, X.; Pechere, A.; Ivancevic, M.K.; Martin, P.-Y.; Keller, A.; Didier, D.; Terrier, F.; Vallee, J.-P

    2005-04-01

    The aim of this study was to refine the description of the renal function based on MR images and through transit-time curve analysis on a normal population and on a population with renal failure, using the quantitative model of the up-slope. Thirty patients referred for a kidney MR exam were divided in a first population with well-functioning kidneys and in a second population with renal failure from ischaemic kidney disease. The perfusion sequence consisted of an intravenous injection of Gd-DTPA and of a fast GRE sequence T1-TFE with 90 deg. magnetisation preparation (Intera 1.5 T MR System, Philips Medical System). To convert the signal intensity into 1/T1, which is proportional to the contrast media concentration, a flow-corrected calibration procedure was used. Following segmentation of regions of interest in the cortex and medulla of the kidney and in the abdominal aorta, outflow curves were obtained and filtered to remove the high frequency fluctuations. The model of the up-slope method was then applied. Significant reduction of the cortical perfusion (Q{sub c}=0.057{+-}0.030 ml/(s 100 g) to Q{sub c}=0.030{+-}0.017 ml/(s 100 g), P<0.013), of the medullary perfusion (Q{sub m}=0.023{+-}0.018 ml/(s 100 g) to Q{sub m}=0.011{+-}0.006 ml/(s 100 g), P<0.046) and of the accumulation of contrast media in the medulla (Q{sub a}=0.005{+-}0.003 ml/(s 100 g) to Q{sub a}=0.0009{+-}0.0008 ml/(s 100 g), P<0.001) were found in presence of renal failure. High correlations were found between the creatinine level and the accumulation Q{sub a} in the medulla (r{sup 2}=0.72, P<0.05), and between the perfusion ratio Q{sub c}/Q{sub m} and the accumulation Q{sub a} in the medulla (r{sup 2}=0.81, P<0.05). No significant difference was found in times to peak between both populations despite a trend showing T{sub a} the time to the end of the increasing contrast accumulation period in the medulla, arriving later for renal failure. Advances in MR signal calibration with the building of

  3. [Restriction endonuclease digest - melting curve analysis: a new SNP genotyping and its application in traditional Chinese medicine authentication].

    Jiang, Chao; Huang, Lu-Qi; Yuan, Yuan; Chen, Min; Hou, Jing-Yi; Wu, Zhi-Gang; Lin, Shu-Fang

    2014-04-01

    Single nucleotide polymorphisms (SNP) is an important molecular marker in traditional Chinese medicine research, and it is widely used in TCM authentication. The present study created a new genotyping method by combining restriction endonuclease digesting with melting curve analysis, which is a stable, rapid and easy doing SNP genotyping method. The new method analyzed SNP genotyping of two chloroplast SNP which was located in or out of the endonuclease recognition site, the results showed that when attaching a 14 bp GC-clamp (cggcgggagggcgg) to 5' end of the primer and selecting suited endonuclease to digest the amplification products, the melting curve of Lonicera japonica and Atractylodes macrocephala were all of double peaks and the adulterants Shan-yin-hua and A. lancea were of single peaks. The results indicated that the method had good stability and reproducibility for identifying authentic medicines from its adulterants. It is a potential SNP genotyping method and named restriction endonuclease digest - melting curve analysis.

  4. A Computerized QC Analysis of TLD Glow Curves for Personal Dosimetry Measurements Using Tag QC Program

    Primo, S.; Datz, H.; Dar, A.

    2014-01-01

    The External Dosimetry Lab (EDL) at the Radiation Safety Division at Soreq Nuclear Research Center (SNRC) is ISO 17025 certified and provides its services to approximately 13,000 users throughout the country from various sectors such as medical, industrial and academic. About 95% of the users are monitored monthly for X-rays, radiation using Thermoluminescence Dosimeter (TLD) cards that contain three LiF:Mg,Ti elements and the other users, who work also with thermal neutrons, use TLD cards that contain four LiF:Mg,Ti elements. All TLD cards are measured with the Thermo 8800pc reader. Suspicious TLD glow curve (GC) can cause wrong dose estimation so the EDL makes great efforts to ensure that each GC undergoes a careful QC procedure. The current QC procedure is performed manually and through a few steps using different softwares and databases in a long and complicated procedure: EDL staff needs to export all the results/GCs to be checked to an Excel file, followed by finding the suspicious GCs, which is done in a different program (WinREMS), According to the GC shapes (Figure 1 illustrates suitable and suspicious GC shapes) and the ratio between the elements result values, the inspecting technician corrects the data. The motivation for developing the new program is the complicated and time consuming process of our the manual procedure to the large amount of TLDs each month (13,000), similarly to other Dosimetry services that use computerized QC GC analysis. it is important to note that only ~25% of the results are above the EDL recorded level (0.10 mSv) and need to be inspected. Thus, the purpose of this paper is to describe a new program, TagQC, which allows a computerized QC GC analysis that identifies automatically, swiftly, and accurately suspicious TLD GC

  5. Size-dependent analysis of a sandwich curved nanobeam integrated with piezomagnetic face-sheets

    Ashraf M. Zenkour

    Full Text Available The aim of this research is to develop nonlocal transient magneto-electro-elastic formulation of a sandwich curved nanobeam including a nano-core and two piezo-magnetic face-sheets subjected to transverse mechanical loads and applied electric and magnetic potentials rest on Pasternak’s foundation. Nonlocal magneto-electro-elastic relations and Hamilton’s principle are used for derivation of the governing equations of motion. The analytical solution based on Fourier solution is presented for a simply-supported sandwich curved nanobeam. The numerical results are presented to investigate influence of significant parameters such as nonlocal parameter, radius of curvature, applied electric and magnetic potentials and two parameters of Pasternak's foundation on the dynamic responses of sandwich curved nanobeam. Keywords: Sandwich curved nanobeam, Dynamic responses, Piezo-magnetic face-sheets, Pasternak’s foundation, Radius of curvature, Nonlocal parameter

  6. New Light Curves and Analysis of the Overcontact Binaries PP Lac and DK Sge

    Sanders, S. J.; Hargis, J. R.; Bradstreet, D. H.

    2004-12-01

    As a by-product of the ongoing work with the Catalog and AtLas of Eclipsing Binaries database (CALEB; Bradstreet et al. 2004), several hundred eclipsing binary systems have been identified that have either unpublished or poor quality light curves. We present new V & Rc light curves for the overcontact systems PP Lac and DK Sge, both chosen because their deep eclipses (peak-to-peak amplitudes of nearly 0.7 mag) help constrain the light curve modelling. Data were obtained using the 41-cm telescope at the Eastern University Observatory equipped with an SBIG ST-10XME CCD. PP Lac (P= 0.40116 d) is a W-type contact binary with only one previously published light curve (Dumont & Maraziti 1990), but the data are sparse and almost non-existent at primary eclipse. Modelling of these data gave varying results; the published mass ratios differ by nearly 0.3. Our data confirms the noted differing eclipse depths but we find the primary eclipse to be total. We present a new light curve solution using Binary Maker 3 (Bradstreet & Steelman 2002) and Wilson-Devinney, finding the mass ratio to be well-constrained by the duration of total eclipse. A period study will be presented using previously existing and newly derived times of minimum light. DK Sge (P=0.62182 d) appears to be an A-type contact binary with no published light curve. The eclipses are partial, with the primary eclipse being deeper by about 0.08 mag. The maxima show evidence of a slight asymmetry, although the light curve appears to be repeatable over the 1 month of observations. We present the first light curve solution using Binary Maker 3 and Wilson-Devinney, but have limited mass ratio constraints due to the absence of radial velocity data. A period study will be presented using previously existing and newly derived times of minimum light.

  7. Integrated analysis on static/dynamic aeroelasticity of curved panels based on a modified local piston theory

    Yang, Zhichun; Zhou, Jian; Gu, Yingsong

    2014-10-01

    A flow field modified local piston theory, which is applied to the integrated analysis on static/dynamic aeroelastic behaviors of curved panels, is proposed in this paper. The local flow field parameters used in the modification are obtained by CFD technique which has the advantage to simulate the steady flow field accurately. This flow field modified local piston theory for aerodynamic loading is applied to the analysis of static aeroelastic deformation and flutter stabilities of curved panels in hypersonic flow. In addition, comparisons are made between results obtained by using the present method and curvature modified method. It shows that when the curvature of the curved panel is relatively small, the static aeroelastic deformations and flutter stability boundaries obtained by these two methods have little difference, while for curved panels with larger curvatures, the static aeroelastic deformation obtained by the present method is larger and the flutter stability boundary is smaller compared with those obtained by the curvature modified method, and the discrepancy increases with the increasing of curvature of panels. Therefore, the existing curvature modified method is non-conservative compared to the proposed flow field modified method based on the consideration of hypersonic flight vehicle safety, and the proposed flow field modified local piston theory for curved panels enlarges the application range of piston theory.

  8. Multilevel Models for the Analysis of Angle-Specific Torque Curves with Application to Master Athletes

    Carvalho Humberto M.

    2015-12-01

    Full Text Available The aim of this paper was to outline a multilevel modeling approach to fit individual angle-specific torque curves describing concentric knee extension and flexion isokinetic muscular actions in Master athletes. The potential of the analytical approach to examine between individual differences across the angle-specific torque curves was illustrated including between-individuals variation due to gender differences at a higher level. Torques in concentric muscular actions of knee extension and knee extension at 60°·s-1 were considered within a range of motion between 5°and 85° (only torques “truly” isokinetic. Multilevel time series models with autoregressive covariance structures with standard multilevel models were superior fits compared with standard multilevel models for repeated measures to fit anglespecific torque curves. Third and fourth order polynomial models were the best fits to describe angle-specific torque curves of isokinetic knee flexion and extension concentric actions, respectively. The fixed exponents allow interpretations for initial acceleration, the angle at peak torque and the decrement of torque after peak torque. Also, the multilevel models were flexible to illustrate the influence of gender differences on the shape of torque throughout the range of motion and in the shape of the curves. The presented multilevel regression models may afford a general framework to examine angle-specific moment curves by isokinetic dynamometry, and add to the understanding mechanisms of strength development, particularly the force-length relationship, both related to performance and injury prevention.

  9. Bootstrap-based procedures for inference in nonparametric receiver-operating characteristic curve regression analysis.

    Rodríguez-Álvarez, María Xosé; Roca-Pardiñas, Javier; Cadarso-Suárez, Carmen; Tahoces, Pablo G

    2018-03-01

    Prior to using a diagnostic test in a routine clinical setting, the rigorous evaluation of its diagnostic accuracy is essential. The receiver-operating characteristic curve is the measure of accuracy most widely used for continuous diagnostic tests. However, the possible impact of extra information about the patient (or even the environment) on diagnostic accuracy also needs to be assessed. In this paper, we focus on an estimator for the covariate-specific receiver-operating characteristic curve based on direct regression modelling and nonparametric smoothing techniques. This approach defines the class of generalised additive models for the receiver-operating characteristic curve. The main aim of the paper is to offer new inferential procedures for testing the effect of covariates on the conditional receiver-operating characteristic curve within the above-mentioned class. Specifically, two different bootstrap-based tests are suggested to check (a) the possible effect of continuous covariates on the receiver-operating characteristic curve and (b) the presence of factor-by-curve interaction terms. The validity of the proposed bootstrap-based procedures is supported by simulations. To facilitate the application of these new procedures in practice, an R-package, known as npROCRegression, is provided and briefly described. Finally, data derived from a computer-aided diagnostic system for the automatic detection of tumour masses in breast cancer is analysed.

  10. Mesenteric Castleman's disease: ultrasound, computed tomography and angiographic appearance

    Malara, F.A.; Price, D.; Fabiny

    2000-01-01

    The localized form of Castleman's disease is rare, and a mesenteric location is particularly unusual. A case of an asymptomatic young woman having the hyaline vascular type is presented and the ultrasound, computed tomography (CT) and angiographic features of the condition are demonstrated. Copyright (1999) Blackwell Science Pty Ltd

  11. Spontaneous coronary artery dissection: complete angiographic resolution without stenting

    Alexandre Abizaid

    2007-09-01

    Full Text Available A case of spontaneous coronary artery dissection in a 49-year-oldwoman is presented. She did not present the classical cardiovascular riskfactors. Etiology and treatment are discussed. She underwent primarypercutaneous coronary intervention of the left anterior descendingartery with no stenting and had complete angiographic resolution.

  12. Angiographic diagnosis of hemorrhage tumours of the small intestine

    Vadon, G.; Ehngloner, L.; Petri, K.

    1980-01-01

    2 angiographic investigations in small intestine tumors, accompanied with hemorrhage are considered. Conclusion is made that the most suitable moment for estimation of small intestine hemorrhage, according to the proper and literature data, is selective angiography. Wide application of the technique for preoperative detection of gastro-inestinal hemorrhage is recommended

  13. Exponential Decay Nonlinear Regression Analysis of Patient Survival Curves: Preliminary Assessment in Non-Small Cell Lung Cancer

    Stewart, David J.; Behrens, Carmen; Roth, Jack; Wistuba, Ignacio I.

    2010-01-01

    Background For processes that follow first order kinetics, exponential decay nonlinear regression analysis (EDNRA) may delineate curve characteristics and suggest processes affecting curve shape. We conducted a preliminary feasibility assessment of EDNRA of patient survival curves. Methods EDNRA was performed on Kaplan-Meier overall survival (OS) and time-to-relapse (TTR) curves for 323 patients with resected NSCLC and on OS and progression-free survival (PFS) curves from selected publications. Results and Conclusions In our resected patients, TTR curves were triphasic with a “cured” fraction of 60.7% (half-life [t1/2] >100,000 months), a rapidly-relapsing group (7.4%, t1/2=5.9 months) and a slowly-relapsing group (31.9%, t1/2=23.6 months). OS was uniphasic (t1/2=74.3 months), suggesting an impact of co-morbidities; hence, tumor molecular characteristics would more likely predict TTR than OS. Of 172 published curves analyzed, 72 (42%) were uniphasic, 92 (53%) were biphasic, 8 (5%) were triphasic. With first-line chemotherapy in advanced NSCLC, 87.5% of curves from 2-3 drug regimens were uniphasic vs only 20% of those with best supportive care or 1 drug (p<0.001). 54% of curves from 2-3 drug regimens had convex rapid-decay phases vs 0% with fewer agents (p<0.001). Curve convexities suggest that discontinuing chemotherapy after 3-6 cycles “synchronizes” patient progression and death. With postoperative adjuvant chemotherapy, the PFS rapid-decay phase accounted for a smaller proportion of the population than in controls (p=0.02) with no significant difference in rapid-decay t1/2, suggesting adjuvant chemotherapy may move a subpopulation of patients with sensitive tumors from the relapsing group to the cured group, with minimal impact on time to relapse for a larger group of patients with resistant tumors. In untreated patients, the proportion of patients in the rapid-decay phase increased (p=0.04) while rapid-decay t1/2 decreased (p=0.0004) with increasing

  14. Differential Clinical Outcomes Between Angiographic Complete Versus Incomplete Coronary Revascularization, According to the Presence of Chronic Kidney Disease in the Drug-Eluting Stent Era.

    Kim, Jihoon; Lee, Joo Myung; Choi, Ki Hong; Rhee, Tae-Min; Hwang, Doyeon; Park, Jonghanne; Ahn, Chul; Park, Taek Kyu; Yang, Jeong Hoon; Song, Young Bin; Choi, Jin-Ho; Hahn, Joo-Yong; Choi, Seung-Hyuk; Gwon, Hyeon-Cheol

    2018-02-15

    There are limited data regarding the prognostic impact of angiographic complete revascularization (CR) in patients with chronic kidney disease (CKD). We sought to investigate the differential prognostic impact of angiographic CR over incomplete revascularization (IR), according to the presence of CKD in the drug-eluting stent era. Between 2003 and 2011 at Samsung Medical Center, consecutive patients with multivessel disease were stratified by the presence of CKD (estimated glomerular filtration rate <60 mL/min per 1.73 m 2 ) and classified according to angiographic CR (residual SYNTAX score=0) or IR. Clinical outcomes were compared between angiographic CR and IR, stratified by the presence of CKD. Primary outcome was patient-oriented composite outcomes (POCO, a composite of all-cause death, myocardial infarction, any revascularization) at 3 years. Inverse probability weighting was performed between the CR and IR groups. A total of 3224 patients were eligible for analysis: 2295 without CKD; 929 with CKD. Among non-CKD patients, angiographic CR showed a significantly lower risk of POCO than IR (17.2% versus 21.7%, adjusted hazard ratio 0.76, 95% confidence interval, 0.62-0.95, P =0.014), mainly driven by a significantly lower risk of any revascularization. Among CKD patients, however, angiographic CR was associated with a significantly higher risk of POCO than IR (37.7% versus 28.4%, adjusted hazard ratio 1.42, 95% confidence interval, 1.08%-1.85%, P =0.011), mainly driven by a significantly higher risk of nonfatal target vessel myocardial infarction. Angiographic CR was associated with reduced risk of POCO than IR in patients without CKD; however, it was associated with a significantly higher risk of POCO and nonfatal myocardial infarction in CKD patients. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  15. High-resolution melting-curve (HRM) analysis for C. meleagridis identification in stool samples.

    Chelbi, Hanen; Essid, Rym; Jelassi, Refka; Bouzekri, Nesrine; Zidi, Ines; Ben Salah, Hamza; Mrad, Ilhem; Ben Sghaier, Ines; Abdelmalek, Rym; Aissa, Sameh; Bouratbine, Aida; Aoun, Karim

    2018-02-01

    Cryptosporidiosis represents a major public health problem. This infection, caused by a protozoan parasite of the genus Cryptosporidium, has been reported worldwide as a frequent cause of diarrhoea. In the immunocompetent host, the typical watery diarrhea can be self-limiting. However, it is severe and chronic, in the immunocompromised host and may cause death. Cryptosporidium spp. are coccidians, which complete their life cycle in both humans and animals. The two species C. hominis and C. parvum are the major cause of human infection. Compared to studies on C. hominis and C. parvum, only a few studies have developed methods to identify C. meleagridis. To develop a new real time PCR-coupled High resolution melting assay allowing the detection for C. meleagridis, in addition of the other dominant species (C. hominis and C. parvum). The polymorphic sequence on the dihydrofolate reductase gene (DHFR) of three species was sequenced to design primers pair and establish a sensitive real-time PCR coupled to a high-resolution melting-curve (HRM) analysis method, allowing the detection of Cryptosporidium sp. and discrimination between three prevalent species in Tunisia. We analyzed a collection of 42 archived human isolates of the three studied species. Real-time PCR coupled to HRM assay allowed detection of Cryptosporidium, using the new designed primers, and basing on melting profile, we can distinguish C. meleagridis species in addition to C. parvum and C. hominis. We developed a qPCR-HRM assay that allows Cryptosporidium genotyping. This method is sensitive and able to distinguish three Cryptosporidium species. Copyright © 2017. Published by Elsevier Ltd.

  16. Comparative analysis of costs for the generation of electrical energy in Brazil using the screening curve

    Barros, Thaisa C. de; Castrillo, Lazara S.; Xavier, Aline G.; Goncalves, Gabriela de L.; Melo, Julio Angelo, E-mail: barros.camara@gmail.com, E-mail: lazaracastrillo@hotmail.com, E-mail: alinegxavier@gmail.com, E-mail: gabilimag_@hotmail.com, E-mail: angelo_mecanic@hotmail.com [Escola Politecnica de Pernambuco (UPE), Recife, PE (Brazil). Departamento de Engenharia Mecanica Industrial

    2017-11-01

    To meet the demand for electric consumption, it is fundamental to prepare an efficient energy planning that guarantees the safe supply of energy, so that the price of kilowatt-hours for the consumer respects the tariff modality and the socio-environmental impact is the smallest possible. In recent years, alternative sources of energy have been gaining considerable space in the Brazilian generating park. Among the many options for energy supply, choosing the most feasible involves the use of techniques that compare all the costs involved in generating electricity from the sources available in the Brazilian energy matrix. The objective of the work is to show a quick, practical and objective tool that performs this comparison and assists in decision making. The method based on the comparison is the Cost of Energy and the tool for the application of the same are the Screening curves, widely used by the International Atomic Energy Agency (IAEA). In this analysis, the following parameters are considered: operating capacity, toxic gas emission rate, fuel consumption and values, fixed and variable costs of operation and maintenance, investment values for each source, construction time and useful life. It is worth noting that the method does not consider in calculations aspects such as inflation, forced interruptions of the plant and other more specific factors. With the work, it was possible to perform an examination of the costs of the generation technologies available in Brazil and, through the obtained data, the economic viability of the generating parks was discussed through simulations in different scenarios, comparing the sources among themselves. (author)

  17. Comparative analysis of costs for the generation of electrical energy in Brazil using the screening curve

    Barros, Thaisa C. de; Castrillo, Lazara S.; Xavier, Aline G.; Goncalves, Gabriela de L.; Melo, Julio Angelo

    2017-01-01

    To meet the demand for electric consumption, it is fundamental to prepare an efficient energy planning that guarantees the safe supply of energy, so that the price of kilowatt-hours for the consumer respects the tariff modality and the socio-environmental impact is the smallest possible. In recent years, alternative sources of energy have been gaining considerable space in the Brazilian generating park. Among the many options for energy supply, choosing the most feasible involves the use of techniques that compare all the costs involved in generating electricity from the sources available in the Brazilian energy matrix. The objective of the work is to show a quick, practical and objective tool that performs this comparison and assists in decision making. The method based on the comparison is the Cost of Energy and the tool for the application of the same are the Screening curves, widely used by the International Atomic Energy Agency (IAEA). In this analysis, the following parameters are considered: operating capacity, toxic gas emission rate, fuel consumption and values, fixed and variable costs of operation and maintenance, investment values for each source, construction time and useful life. It is worth noting that the method does not consider in calculations aspects such as inflation, forced interruptions of the plant and other more specific factors. With the work, it was possible to perform an examination of the costs of the generation technologies available in Brazil and, through the obtained data, the economic viability of the generating parks was discussed through simulations in different scenarios, comparing the sources among themselves. (author)

  18. Analysis of diffusion paths for photovoltaic technology based on experience curves

    Poponi, Daniele

    2003-04-01

    This paper assesses the prospects for diffusion of photovoltaic (PV) technology for electricity generation in grid-connected systems. The analysis begins with the calculation of the break-even price of PV systems and modules, which is the price that can assure commercial viability without incentives or subsidies. The calculated average break-even price of PV systems for building-integrated applications is about US dollars 3.2/W p but can go up to about US dollars 4.5/W p in areas with very good solar irradiation and if a low real discount rate is applied. These are higher values than the break-even prices estimated in the literature to date. PV system break-even prices for intermediate load generation in utility-owned systems are also calculated, their average being about US dollars 1/W p The methodology of experience curves is used to predict what would be the different levels of cumulative world PV shipments required to reach the calculated break-even prices of PV systems, assuming different trends in the relationship between price and the increase in cumulative shipments. The years in which the break-even levels of cumulative shipments could be theoretically obtained are then calculated by considering different market growth rates. Photovoltaics could enter the niche of building-integrated applications without incentives in the first years of the next decade, provided that the PR is 80% and the average annual world market growth rate is at least 15%. The final part of the paper analyzes the niche markets or applications that seem promising for the diffusion of photovoltaics in the next few years (Author)

  19. Prediction of low birth weight delivery by maternal status and its validation: Decision curve analysis

    Mehri Rejali

    2017-01-01

    Full Text Available Background: In this study, we evaluated assessed elements connected with low birth weight (LBW and used decision curve analysis (DCA to define a scale to anticipate the probability of having a LBW newborn child. Methods: This hospital-based case–control study was led in Arak Hospital in Iran. The study included 470 mothers with LBW neonate and 470 mothers with natural neonates. Information were gathered by meeting moms utilizing preplanned organized questionnaire and from hospital records. The estimated probabilities of detecting LBW were calculated using the logistic regression and DCA to quantify the clinical consequences and its validation. Results: Factors significantly associated with LBW were premature membrane rupture (odds ratio [OR] = 3.18 [1.882–5.384], former LBW infants (OR = 2.99 [1.510–5.932], premature pain (OR = 2.70 [1.659–4.415], hypertension in pregnancy (OR = 2.39 [1.429–4.019], last trimester of pregnancy bleeding (OR = 2.58 [1.018–6.583], mother age >30 (OR = 2.17 [1.350–3.498]. However, with DCA, the prediction model made on these 15 variables has a net benefit (NB of 0.3110 is best predictive with the highest NB. NB has simple clinical interpretation and utilizing the model is what might as well be called a procedure that distinguished what might as well be called 31.1 LBW per 100 cases with no superfluous recognize. Conclusions: It is conceivable to foresee LBW utilizing a prediction model show in light of noteworthy hazard components connected with LBW. The majority of the hazard elements for LBW are preventable, and moms can be alluded amid early pregnancy to a middle which is furnished with facilities for administration of high hazard pregnancy and LBW infant.

  20. ‘‘Blind'' mapping of genic DNA sequence polymorphisms in Lolium perenne L. by high resolution melting curve analysis

    Studer, Bruno; Jensen, Louise Bach; Fiil, Alice

    2009-01-01

    High resolution melting curve analysis (HRM) measures dissociation of double stranded DNA of a PCR product amplified in the presence of a saturating fluorescence dye. Recently, HRM proved successful to genotype DNA sequence polymorphisms such as SSRs and SNPs based on the shape of the melting...... curves. In this study, HRM was used for simultaneous screening and genotyping of genic DNA sequence polymorphisms identified in the Lolium perenne F2 mapping population VrnA. Melting profiles of PCR products amplified from previously published gene loci and from a novel gene putatively involved...

  1. More basic approach to the analysis of multiple specimen R-curves for determination of J/sub c/

    Carlson, K.W.; Williams, J.A.

    1980-02-01

    Multiple specimen J-R curves were developed for groups of 1T compact specimens with different a/W values and depth of side grooving. The purpose of this investigation was to determine J/sub c/ (J at onset of crack extension) for each group. Judicious selection of points on the load versus load-line deflection record at which to unload and heat tint specimens permitted direct observation of approximate onset of crack extension. It was found that the present recommended procedure for determining J/sub c/ from multiple specimen R-curves, which is being considered for standardization, consistently yielded nonconservative J/sub c/ values. A more basic approach to analyzing multiple specimen R-curves is presented, applied, and discussed. This analysis determined J/sub c/ values that closely corresponded to actual observed onset of crack extension

  2. Numerical analysis of unsteady conjugate heat transfer for initial evolution of thermal stratification in a curved pipe

    Jo, Jong Chull; Kim, Wee Kyung; Kim, Yun Il; Cho, Sang Jin; Choi, Seok Ki

    2000-01-01

    A detailed numerical analysis of initial evolution of thermal stratification in a curved pipe with a finite wall thickness is performed. A primary emphasis of the present study is placed on the investigation of the effect of existence of pipe wall thickness on the evolution of thermal stratification. A simple and convenient numerical method of treating the unsteady conjugate heat transfer in Cartesian as well as non-orthogonal coordinate systems is presented. The proposed unsteady conjugate heat transfer analysis method is implemented in a finite volume thermal-hydraulic computer code based on a cell-centered, non-staggered grid arrangement, the SIMPLEC algorithm and a higher-order bounded convection scheme. Calculations are performed for initial evolution of thermal stratification with high Richardson number in a curved pipe. The predicted results show that the thermally stratified flow and transient conjugate heat transfer in a curved pipe with a specified wall thickness can be satisfactorily analyzed by using the numerical method presented in this paper. As the result, the present analysis method is considered to be effective for the determination of transient temperature distributions in the wall of curved piping system subjected to internally thermal stratification. In addition, the method can be extended to be applicable for the simulation of turbulent flow of thermally stratified fluid

  3. Tracer concentration curves and residence time analysis in technological flow systems. 2

    Pippel, W.

    1976-01-01

    Tracer concentration curves measured in flow systems by means of radioactive isotopes are treated as a two dimensional random process. Comparing them with the family distribution functions described in part I, it follows that only in case of ergodic behaviour of the system tracer curves can be considered as age distribution functions. The conception of ergodicity in residence time systems has been explained with the aid of a time function measurable by a special method of radioactive tracer technique and by the mean value of the residence time obtainable from this function. Furthermore, technological consequences in evaluating tracer concentration curves of real flow systems are discussed with respect to supposed ergodic or nonergodic behaviour. These considerations are of special importance for flow systems with temporary fluctuations in structure. (author)

  4. Quantitative analysis by laser-induced breakdown spectroscopy based on generalized curves of growth

    Aragón, C., E-mail: carlos.aragon@unavarra.es; Aguilera, J.A.

    2015-08-01

    A method for quantitative elemental analysis by laser-induced breakdown spectroscopy (LIBS) is proposed. The method (Cσ-LIBS) is based on Cσ graphs, generalized curves of growth which allow including several lines of various elements at different concentrations. A so-called homogeneous double (HD) model of the laser-induced plasma is used, defined by an integration over a single-region of the radiative transfer equation, combined with a separated treatment for neutral atoms (z = 0) and singly-charged ions (z = 1) in Cσ graphs and characteristic parameters. The procedure includes a criterion, based on a model limit, for eliminating data which, due to a high line intensity or concentration, are not well described by the HD model. An initial procedure provides a set of parameters (βA){sup z}, (ηNl){sup z}, T{sup z} and N{sub e}{sup z} (z = 0, 1) which characterize the plasma and the LIBS system. After characterization, two different analytical procedures, resulting in relative and absolute concentrations, may be applied. To test the method, fused glass samples prepared from certified slags and pure compounds are analyzed. We determine concentrations of Ca, Mn, Mg, V, Ti, Si and Al relative to Fe in three samples prepared from slags, and absolute concentrations of Fe, Ca and Mn in three samples prepared from Fe{sub 2}O{sub 3}, CaCO{sub 3} and Mn{sub 2}O{sub 3}. The accuracy obtained is 3.2% on the average for relative concentrations and 9.2% for absolute concentrations. - Highlights: • Method for quantitative analysis by LIBS, based on Csigma graphs • Conventional calibration is replaced with characterization of the LIBS system. • All elements are determined from measurement of one or two Csigma graphs. • The method is tested with fused glass disks prepared from slags and pure compounds. • Accurate results for relative (3.2%) and absolute concentrations (9.2%)

  5. Load curves analysis under operational and economics focus; Analise de curvas de carga sob enfoques operativos e economicos

    Matos, R S; Cardoso, A F; Fleury, M E.V. [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)

    1988-12-31

    This work aims to present the analysis of load curves performed by the short term planning sectors of several subsidiaries, independently of the methodologies used. In order to do so some peculiar occurrences were selected which show the influence of factors that are external to the electric power system. In such way, the analysis of past situations proves to be an important tool in the forecasting work so that a better planning may be achieved. 13 figs., 2 tabs.

  6. Polynomial curve fitting for control rod worth using least square numerical analysis

    Muhammad Husamuddin Abdul Khalil; Mark Dennis Usang; Julia Abdul Karim; Mohd Amin Sharifuldin Salleh

    2012-01-01

    RTP must have sufficient excess reactivity to compensate the negative reactivity feedback effects such as those caused by the fuel temperature and power defects of reactivity, fuel burn-up and to allow full power operation for predetermined period of time. To compensate this excess reactivity, it is necessary to introduce an amount of negative reactivity by adjusting or controlling the control rods at will. Control rod worth depends largely upon the value of the neutron flux at the location of the rod and reflected by a polynomial curve. Purpose of this paper is to rule out the polynomial curve fitting using least square numerical techniques via MATLAB compatible language. (author)

  7. Limitations of acceptability curves for presenting uncertainty in cost-effectiveness analysis

    Groot Koerkamp, Bas; Hunink, M. G. Myriam; Stijnen, Theo; Hammitt, James K.; Kuntz, Karen M.; Weinstein, Milton C.

    2007-01-01

    Clinical journals increasingly illustrate uncertainty about the cost and effect of health care interventions using cost-effectiveness acceptability curves (CEACs). CEACs present the probability that each competing alternative is optimal for a range of values of the cost-effectiveness threshold. The

  8. Intraneural stimulation using wire-microelectrode arrays: analysis of force steps in recruitment curves

    Smit, J.P.A.; Rutten, Wim; Boom, H.B.K.

    1996-01-01

    In acute experiments on six Wistar rats, a wire-microelectrode array was inserted into the common peroneal nerve. A 5-channel array and a 24-channel array were available. Each electrode in the array was used to generate a twitch contraction force recruitment curve for the extensor digitorum longus

  9. The Impact of Grading on a Curve: Assessing the Results of Kulick and Wright's Simulation Analysis

    Bailey, Gary L.; Steed, Ronald C.

    2012-01-01

    Kulick and Wright concluded, based on theoretical mathematical simulations of hypothetical student exam scores, that assigning exam grades to students based on the relative position of their exam performance scores within a normal curve may be unfair, given the role that randomness plays in any given student's performance on any given exam.…

  10. Curve-of-growth analysis of a red giant in the globular cluster M13

    Griffin, R.

    1979-01-01

    A coude spectrogram of a red giant (L973) in the globular cluster M13 is analysed, with respect to α Boo, by the differential curve-of-growth technique. The overall metal abundance is found to be approximately one-tenth of that of α Boo, or one-fortieth that of the Sun. (author)

  11. Analysis of flux-flow curves in superconductors as a function of temperature

    Boboshko, N.

    1978-01-01

    A phenomenological method to analyse the experimental data of flux-flow resistivity in superconductors as a function of temperature is proposed and successfully applied to existing data for t = kappa >= 0.07. An empirical curve relating the flux-flow resistivity with the Ginsburg-Landau parameter kappa was obtained. (author)

  12. On the analysis of Canadian Holstein dairy cow lactation curves using standard growth functions

    López, S.; France, J.; Odongo, N.E.; McBride, R.A.; Kebreab, E.; Alzahal, O.; McBride, B.W.; Dijkstra, J.

    2015-01-01

    Six classical growth functions (monomolecular, Schumacher, Gompertz, logistic, Richards, and Morgan) were fitted to individual and average (by parity) cumulative milk production curves of Canadian Holstein dairy cows. The data analyzed consisted of approximately 91,000 daily milk yield records

  13. Parent Involvement and Science Achievement: A Cross-Classified Multilevel Latent Growth Curve Analysis

    Johnson, Ursula Y.; Hull, Darrell M.

    2014-01-01

    The authors examined science achievement growth at Grades 3, 5, and 8 and parent school involvement at the same time points using the Early Childhood Longitudinal Study-Kindergarten Class of 1998-1999. Data were analyzed using cross-classified multilevel latent growth curve modeling with time invariant and varying covariates. School-based…

  14. Sexual Bias and Household Consumption : A Semiparametic Analysis of Engel curves in Rural China

    Gong, X.; van Soest, A.H.O.; Zhang, P.

    2000-01-01

    We analyze Engel curves for nuclear households in rural China. The sample includes more than 5000 nuclear families covering nineteen out of thirty Chinese provinces. We consider expenditures on food, also subdivided into several food subcategories such as cereals, or meat and fish, and other

  15. Detection of Anti-Hepatitis B Virus Drug Resistance Mutations Based on Multicolor Melting Curve Analysis.

    Mou, Yi; Athar, Muhammad Ammar; Wu, Yuzhen; Xu, Ye; Wu, Jianhua; Xu, Zhenxing; Hayder, Zulfiqar; Khan, Saeed; Idrees, Muhammad; Nasir, Muhammad Israr; Liao, Yiqun; Li, Qingge

    2016-11-01

    Detection of anti-hepatitis B virus (HBV) drug resistance mutations is critical for therapeutic decisions for chronic hepatitis B virus infection. We describe a real-time PCR-based assay using multicolor melting curve analysis (MMCA) that could accurately detect 24 HBV nucleotide mutations at 10 amino acid positions in the reverse transcriptase region of the HBV polymerase gene. The two-reaction assay had a limit of detection of 5 copies per reaction and could detect a minor mutant population (5% of the total population) with the reverse transcriptase M204V amino acid mutation in the presence of the major wild-type population when the overall concentration was 10 4 copies/μl. The assay could be finished within 3 h, and the cost of materials for each sample was less than $10. Clinical validation studies using three groups of samples from both nucleos(t)ide analog-treated and -untreated patients showed that the results for 99.3% (840/846) of the samples and 99.9% (8,454/8,460) of the amino acids were concordant with those of Sanger sequencing of the PCR amplicon from the HBV reverse transcriptase region (PCR Sanger sequencing). HBV DNA in six samples with mixed infections consisting of minor mutant subpopulations was undetected by the PCR Sanger sequencing method but was detected by MMCA, and the results were confirmed by coamplification at a lower denaturation temperature-PCR Sanger sequencing. Among the treated patients, 48.6% (103/212) harbored viruses that displayed lamivudine monoresistance, adefovir monoresistance, entecavir resistance, or lamivudine and adefovir resistance. Among the untreated patients, the Chinese group had more mutation-containing samples than did the Pakistani group (3.3% versus 0.56%). Because of its accuracy, rapidness, wide-range coverage, and cost-effectiveness, the real-time PCR assay could be a robust tool for the detection if anti-HBV drug resistance mutations in resource-limited countries. Copyright © 2016, American Society for

  16. Performance curves of medical researchers during their career: analysis of scientific production from a retrospective cohort.

    Duclos, Antoine; Herquelot, Eléonore; Polazzi, Stéphanie; Malbezin, Muriel; Claris, Olivier

    2017-02-24

    To establish the pattern of change in individual scientific production over the career of medical researchers. Retrospective cohort based on prospectively collected data in a hospital information system. Multicentre university hospital in France. Two distinct populations of 1835 researchers (full professors vs non-academic physicians) having produced 44 723 publications between 1995 and 2014. Annual number of publications referenced in Medline/PubMed with a sensitivity analysis based on publications as first/last author and in high impact journals. The individual volume of publications was modelled by age using generalised estimating equations adjusted for birth cohort, biomedical discipline and academic position of researchers. Averaged over the whole career, the annual number of publications was 5.28 (95% CI 4.90 to 5.69) among professors compared to 0.82 (95% CI 0.76 to 0.89) among non-academic physicians (pscientific production between 25 and 35 years (adjusted incidence rate ratio 102.20, 95% CI 60.99 to 171.30), a maturation phase with a slower increase from 35 to 50 years (2.10, 95% CI 1.75 to 2.51) until a stabilisation phase with constant production followed by a potential decline at the end of career (0.90, 95% CI 0.77 to 1.06). The non-academic physicians experienced a slower pace of learning curve at the beginning of their careers (42.38, 95% CI 25.37 to 70.81) followed by a smaller increase in the annual number of publications (1.29, 95% CI 1.11 to 1.51). Compared to full professors, non-academic physicians had a poor capacity to publish, indicating a low productivity when medical doctors have limited time or little interest in undertaking research. This finding highlights the potential for rethinking the missions of medical doctors towards an enlargement of scientific prerogatives in favour of progress in global knowledge. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go

  17. On the analysis of Canadian Holstein dairy cow lactation curves using standard growth functions.

    López, S; France, J; Odongo, N E; McBride, R A; Kebreab, E; AlZahal, O; McBride, B W; Dijkstra, J

    2015-04-01

    Six classical growth functions (monomolecular, Schumacher, Gompertz, logistic, Richards, and Morgan) were fitted to individual and average (by parity) cumulative milk production curves of Canadian Holstein dairy cows. The data analyzed consisted of approximately 91,000 daily milk yield records corresponding to 122 first, 99 second, and 92 third parity individual lactation curves. The functions were fitted using nonlinear regression procedures, and their performance was assessed using goodness-of-fit statistics (coefficient of determination, residual mean squares, Akaike information criterion, and the correlation and concordance coefficients between observed and adjusted milk yields at several days in milk). Overall, all the growth functions evaluated showed an acceptable fit to the cumulative milk production curves, with the Richards equation ranking first (smallest Akaike information criterion) followed by the Morgan equation. Differences among the functions in their goodness-of-fit were enlarged when fitted to average curves by parity, where the sigmoidal functions with a variable point of inflection (Richards and Morgan) outperformed the other 4 equations. All the functions provided satisfactory predictions of milk yield (calculated from the first derivative of the functions) at different lactation stages, from early to late lactation. The Richards and Morgan equations provided the most accurate estimates of peak yield and total milk production per 305-d lactation, whereas the least accurate estimates were obtained with the logistic equation. In conclusion, classical growth functions (especially sigmoidal functions with a variable point of inflection) proved to be feasible alternatives to fit cumulative milk production curves of dairy cows, resulting in suitable statistical performance and accurate estimates of lactation traits. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  18. The value of regional wall motion abnormalities on 99Tcm-MIBI gated cardiac SPECT in predicting angiographic stenoses of coronary artery

    Li Dianfu; Huang Jun; Zhu Tiebing; Wang Liansheng; Yang Zhijian; Feng Jianlin; Li Jianhua; Chen Jianwei; Chang Guojun

    2004-01-01

    Objective: To determine the magnitude of angiographic stenoses of coronary artery in reversible regional wall motion abnormalities (RWMA) present in exercise stress 99 Tc m -methoxyisobutylisonitrile (MIBI) gated SPECT myocardial perfusion imaging (MPI). Methods: One hundred and sixteen patients undergoing coronary angiography two weeks before and after the exercise stress 99 Tc m -MIBI gated SPECT MPI. Images were acquired 15 to 20 min after stress. A five grades and twenty segments marking system was introduced to assess the RWMA and thickening of left ventricles. Results: The sensitivity of reversible RWMA for detecting ≥75% angiographic stenoses was 65%, with a specificity of 97%. Reversible RWMA has a high positive predictive value (98%) for stratification between severe angiographic stenoses of 75% and non-severe stenoses (less than 75%). Multivariate analysis showed that the post-stress wall motion (SSSWM), exercise wall motion differentiation value (SDSWM) and summed stress score (SSS) were the independent risk factor of coronary artery jeopardy score. Conclusions: Reversible RWMA, as shown by exercise stress 99 Tc m -MIBI gated SPECT MPI, is a significant predictor of angiographic disease with very high specificity and positive predictive values. Exercise reversible RWMA can rise the assessment value of angiographic severity in MPI

  19. Quantitative assessment of angiographic perfusion reduction using color-coded digital subtraction angiography during transarterial chemoembolization.

    Wang, Ji; Cheng, Jie-Jun; Huang, Kai-Yi; Zhuang, Zhi-Guo; Zhang, Xue-Bin; Chi, Jia-Chang; Hua, Xiao-Lan; Xu, Jian-Rong

    2016-03-01

    The aim of this study was to develop a quantitative measurement of perfusion reduction using color-coded digital subtraction angiography (ccDSA) to monitor intra-procedural arterial stasis during TACE. A total number of 35 patients with hepatocellular carcinoma who had undergone TACE were enrolled into the study. Pre- and post-two-dimensional digital subtraction angiography scans were conducted with same protocol and post-processed with ccDSA prototype software. Time-contrast-intensity (CI[t]) curve was obtained by region-of-interest (ROI) measurement on the generated ccDSA image. Quantitative 2D perfusion parameters time to peak, area under the curve (AUC), maximum upslope, and contrast intensity peak (CI-Peak) derived from the ROI-based CI[t] curve for pre- and post-TACE were evaluated to assess the reduction of antegrade blood flow and tumor blush. Relationships between 2D perfusion parameters, subjective angiographic chemoembolization endpoint (SACE) scale, and clinical outcomes were analyzed. Area normalized AUC and CI-Peak revealed significant reduction after the TACE (P SACE level III and a reduction ranging from 60% to 70% was equivalent to SACE level IV. For intermediate reduction (SACE level III), better tumor response was found after TACE rather than a higher reduction (SACE level IV). ccDSA application provides an objective approach to quantify the perfusion reduction and subjectively evaluate the arterial stasis of antegrade blood flow and tumor blush caused by TACE.

  20. Factors predicting early postpartum glucose intolerance in Japanese women with gestational diabetes mellitus: decision-curve analysis.

    Kondo, M; Nagao, Y; Mahbub, M H; Tanabe, Tsuyoshi; Tanizawa, Y

    2018-04-29

    To identify factors predicting early postpartum glucose intolerance in Japanese women with gestational diabetes mellitus, using decision-curve analysis. A retrospective cohort study was performed. The participants were 123 Japanese women with gestational diabetes who underwent 75-g oral glucose tolerance tests at 8-12 weeks after delivery. They were divided into a glucose intolerance and a normal glucose tolerance group based on postpartum oral glucose tolerance test results. Analysis of the pregnancy oral glucose tolerance test results showed predictive factors for postpartum glucose intolerance. We also evaluated the clinical usefulness of the prediction model based on decision-curve analysis. Of 123 women, 78 (63.4%) had normoglycaemia and 45 (36.6%) had glucose intolerance. Multivariable logistic regression analysis showed insulinogenic index/fasting immunoreactive insulin and summation of glucose levels, assessed during pregnancy oral glucose tolerance tests (total glucose), to be independent risk factors for postpartum glucose intolerance. Evaluating the regression models, the best discrimination (area under the curve 0.725) was obtained using the basic model (i.e. age, family history of diabetes, BMI ≥25 kg/m 2 and use of insulin during pregnancy) plus insulinogenic index/fasting immunoreactive insulin intolerance. Insulinogenic index/fasting immunoreactive insulin calculated using oral glucose tolerance test results during pregnancy is potentially useful for predicting early postpartum glucose intolerance in Japanese women with gestational diabetes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Transit-time flow measurement as a predictor of coronary bypass graft failure at one year angiographic follow-up

    Lehnert, Per; Møller, Christian H; Damgaard, Sune

    2015-01-01

    on graft vessel type, anastomatic configuration, and coronary artery size. RESULTS: Nine hundred eighty-two coronary anastomoses were performed of which 12% had signs of graft failure at one year angiographic follow-up. In internal mammary arteries (IMAs), analysis showed a 4% decrease in graft failure......BACKGROUND: Transit-time flow measurement (TTFM) is a commonly used intraoperative method for evaluation of coronary artery bypass graft (CABG) anastomoses. This study was undertaken to determine whether TTFM can also be used to predict graft patency at one year postsurgery. METHODS: Three hundred...... forty-five CABG patients with intraoperative graft flow measurements and one year angiographic follow-up were analyzed. Graft failure was defined as more than 50% stenosis including the "string sign." Logistic regression analysis was used to analyze the risk of graft failure after one year based...

  2. Fitting sediment rating curves using regression analysis: a case study of Russian Arctic rivers

    N. I. Tananaev

    2015-03-01

    Full Text Available Published suspended sediment data for Arctic rivers is scarce. Suspended sediment rating curves for three medium to large rivers of the Russian Arctic were obtained using various curve-fitting techniques. Due to the biased sampling strategy, the raw datasets do not exhibit log-normal distribution, which restricts the applicability of a log-transformed linear fit. Non-linear (power model coefficients were estimated using the Levenberg-Marquardt, Nelder-Mead and Hooke-Jeeves algorithms, all of which generally showed close agreement. A non-linear power model employing the Levenberg-Marquardt parameter evaluation algorithm was identified as an optimal statistical solution of the problem. Long-term annual suspended sediment loads estimated using the non-linear power model are, in general, consistent with previously published results.

  3. Fitting sediment rating curves using regression analysis: a case study of Russian Arctic rivers

    Tananaev, N. I.

    2015-03-01

    Published suspended sediment data for Arctic rivers is scarce. Suspended sediment rating curves for three medium to large rivers of the Russian Arctic were obtained using various curve-fitting techniques. Due to the biased sampling strategy, the raw datasets do not exhibit log-normal distribution, which restricts the applicability of a log-transformed linear fit. Non-linear (power) model coefficients were estimated using the Levenberg-Marquardt, Nelder-Mead and Hooke-Jeeves algorithms, all of which generally showed close agreement. A non-linear power model employing the Levenberg-Marquardt parameter evaluation algorithm was identified as an optimal statistical solution of the problem. Long-term annual suspended sediment loads estimated using the non-linear power model are, in general, consistent with previously published results.

  4. Theoretical and computational analysis of IFR beam transport on curved channels

    Rienstra, W.W.

    1987-01-01

    With the successful demonstration at Sandia National Laboratory and at Lawrence Livermore Laboratory of ion focused regime (IFR) electron beam guiding in accelerators there has developed interest in using IFR channels to steer beams along curved paths. The authors report the calculations of the expected emittance growth from such channels and the results of the TRACKER code simulations of IFR steering with the assistance of strong focus sector magnets

  5. Biological radiation dose estimation by chromosomal aberrations analysis in human peripheral blood (dose-effect curve)

    Al-Achkar, W.

    2001-09-01

    In order to draw a dose-effect curve, experimentally gamma ray induced chromosomal aberrations in human peripheral lymphocytes from eight healthy people were studied. Samples from 4 males and 4 females were irradiated in tubes with 0.15, 0.25, 0.5, 1, 1.5, 2, 2.5 gray of gamma ray (Co 60 at dose rate 0.3 Gy/min). Irradiated and control samples were incubated in 37 centigrade for 48 hours cell cultures. Cell cultures then were stopped and metaphases spread, Giemsa stained to score the induced chromosomal aberrations. Chromosomal aberrations from 67888 metaphases were scored. Curves from the total number of dicentrics, dicentrics + rings and total numbers of breaks in cell for each individual or for all people were drawn. An increase of all chromosomal aberrations types with the elevation of the doses was observed. The yield of chromosome aberrations is related to the dose used. These curves give a quick useful estimation of the accidentally radiation exposure. (author)

  6. CONFIRMATION OF HOT JUPITER KEPLER-41b VIA PHASE CURVE ANALYSIS

    Quintana, Elisa V.; Rowe, Jason F.; Caldwell, Douglas A.; Christiansen, Jessie L.; Jenkins, Jon M.; Morris, Robert L.; Smith, Jeffrey C.; Thompson, Susan E.; Barclay, Thomas; Howell, Steve B.; Borucki, William J.; Sanderfer, Dwight T.; Still, Martin; Ciardi, David R.; Demory, Brice-Olivier; Klaus, Todd C.; Fulton, Benjamin J.; Shporer, Avi

    2013-01-01

    We present high precision photometry of Kepler-41, a giant planet in a 1.86 day orbit around a G6V star that was recently confirmed through radial velocity measurements. We have developed a new method to confirm giant planets solely from the photometric light curve, and we apply this method herein to Kepler-41 to establish the validity of this technique. We generate a full phase photometric model by including the primary and secondary transits, ellipsoidal variations, Doppler beaming, and reflected/emitted light from the planet. Third light contamination scenarios that can mimic a planetary transit signal are simulated by injecting a full range of dilution values into the model, and we re-fit each diluted light curve model to the light curve. The resulting constraints on the maximum occultation depth and stellar density combined with stellar evolution models rules out stellar blends and provides a measurement of the planet's mass, size, and temperature. We expect about two dozen Kepler giant planets can be confirmed via this method.

  7. Technology S-curves in renewable energy alternatives: Analysis and implications for industry and government

    Schilling, Melissa A.; Esmundo, Melissa

    2009-01-01

    Plotting the performance of a technology against the money or effort invested in it most often yields an S-shaped curve: slow initial improvement, then accelerated improvement, then diminishing improvement. These S-curves can be used to gain insight into the relative payoff of investment in competing technologies, as well as providing some insight into when and why some technologies overtake others in the race for dominance. Analyzing renewable energies from such a technology S-curve perspective reveals some surprising and important implications for both government and industry. Using data on government R and D investment and technological improvement (in the form of cost reductions), we show that both wind energy and geothermal energy are poised to become more economical than fossil fuels within a relatively short time frame. The evidence further suggests that R and D for wind and geothermal technologies has been under-funded by national governments relative to funding for solar technologies, and government funding of fossil fuel technologies might be excessive given the diminishing performance of those technologies.

  8. Statistically generated weighted curve fit of residual functions for modal analysis of structures

    Bookout, P. S.

    1995-01-01

    A statistically generated weighting function for a second-order polynomial curve fit of residual functions has been developed. The residual flexibility test method, from which a residual function is generated, is a procedure for modal testing large structures in an external constraint-free environment to measure the effects of higher order modes and interface stiffness. This test method is applicable to structures with distinct degree-of-freedom interfaces to other system components. A theoretical residual function in the displacement/force domain has the characteristics of a relatively flat line in the lower frequencies and a slight upward curvature in the higher frequency range. In the test residual function, the above-mentioned characteristics can be seen in the data, but due to the present limitations in the modal parameter evaluation (natural frequencies and mode shapes) of test data, the residual function has regions of ragged data. A second order polynomial curve fit is required to obtain the residual flexibility term. A weighting function of the data is generated by examining the variances between neighboring data points. From a weighted second-order polynomial curve fit, an accurate residual flexibility value can be obtained. The residual flexibility value and free-free modes from testing are used to improve a mathematical model of the structure. The residual flexibility modal test method is applied to a straight beam with a trunnion appendage and a space shuttle payload pallet simulator.

  9. Making the Most of Kepler Photometry: Characterizing Exoplanets through Phase Curve Analysis

    Esteves Lisa J.

    2015-01-01

    Full Text Available The Kepler mission’s long-term monitoring of stars through high-precision photometry has not only revealed a plethora of exoplanet transits but also provided valuable data for characterizing a subset of these planets. Using over four years of Kepler observations, we have derived phase curves for over a dozen planets, and use these measurements to constrain their mass, brightness/temperature and energy redistribution between the day and the night sides. In our new study, we also investigate possible offsets of the peak brightness of the phase curve, which could be indicative of inhomogeneous clouds and/or substantial winds in the planet’s atmosphere. We find significant offsets for over a half-dozen planets. With this growing sample of measured phase curves, we are able to better examine the trends of hot Jupiter energy budgets and albedos, and for the first time relate these properties to the presence of clouds or winds on a planet.

  10. The thermoluminescence glow-curve analysis using GlowFit - the new powerful tool for deconvolution

    Puchalska, M.; Bilski, P.

    2005-10-01

    A new computer program, GlowFit, for deconvoluting first-order kinetics thermoluminescence (TL) glow-curves has been developed. A non-linear function describing a single glow-peak is fitted to experimental points using the least squares Levenberg-Marquardt method. The main advantage of GlowFit is in its ability to resolve complex TL glow-curves consisting of strongly overlapping peaks, such as those observed in heavily doped LiF:Mg,Ti (MTT) detectors. This resolution is achieved mainly by setting constraints or by fixing selected parameters. The initial values of the fitted parameters are placed in the so-called pattern files. GlowFit is a Microsoft Windows-operated user-friendly program. Its graphic interface enables easy intuitive manipulation of glow-peaks, at the initial stage (parameter initialization) and at the final stage (manual adjustment) of fitting peak parameters to the glow-curves. The program is freely downloadable from the web site www.ifj.edu.pl/NPP/deconvolution.htm (author)

  11. Testing Environmental Kuznets Curve in the Selected Transition Economies with Panel Smooth Transition Regression Analysis

    Mahmut Zortuk

    2016-08-01

    Full Text Available The Environmental Kuznets Curve (EKC introduces an inverted U-shaped relationship between environmental pollution and economic development. The inverted U-shaped curve is seen as complete pattern for developed economies. However, our study tests the EKC for developing transition economies of European Union, therefore, our results could make a significant contribution to the literature. In this paper, the relationship between carbon dioxide (CO2 emissions, gross domestic product (GDP, energy use and urban population is investigated in the Transition Economies (Bulgaria, Croatia, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia and Slovenia. Environmental Kuznets Curve is tested by panel smooth transition regression for these economies for 1993 – 2010 periods. As a result of study, the null hypothesis of linearity was rejected and no-remaining nonlinearity test showed that there is a smooth transition exists between two regimes (below $5176 GDP per capita is first one and above $5176 GDP per capita is second one in the related period for these economies.

  12. Relationships between each part of the spinal curves and upright posture using Multiple stepwise linear regression analysis.

    Boulet, Sebastien; Boudot, Elsa; Houel, Nicolas

    2016-05-03

    Back pain is a common reason for consultation in primary healthcare clinical practice, and has effects on daily activities and posture. Relationships between the whole spine and upright posture, however, remain unknown. The aim of this study was to identify the relationship between each spinal curve and centre of pressure position as well as velocity for healthy subjects. Twenty-one male subjects performed quiet stance in natural position. Each upright posture was then recorded using an optoelectronics system (Vicon Nexus) synchronized with two force plates. At each moment, polynomial interpolations of markers attached on the spine segment were used to compute cervical lordosis, thoracic kyphosis and lumbar lordosis angle curves. Mean of centre of pressure position and velocity was then computed. Multiple stepwise linear regression analysis showed that the position and velocity of centre of pressure associated with each part of the spinal curves were defined as best predictors of the lumbar lordosis angle (R(2)=0.45; p=1.65*10-10) and the thoracic kyphosis angle (R(2)=0.54; p=4.89*10-13) of healthy subjects in quiet stance. This study showed the relationships between each of cervical, thoracic, lumbar curvatures, and centre of pressure's fluctuation during free quiet standing using non-invasive full spinal curve exploration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Analysis of contrast-enhanced ultrasonography using time-intensity curves in prostatic hyperplasia and prostate cancer

    Fang Junchu; Chen Ming; Sun Huifen

    2008-01-01

    Objective: To study the characters of time-intensity curve of contrast-enhanced ultrasonography in benign prostate hyperplasia (BPH) and prostate cancer. Methods: 2.4 ml Sono Vue were injected as a bolus in 40 patients, 23 patients with BPH and 17 with prostate cancer. High perfusion area in both inner and outer gland were measured with time-intensity curves. Results: It was proved by the time-intensity curves that, in BPH cases, the outer prostate gland presented with mild enhancedment and slow wash-off, while the inner gland presented with moderate enhancedment and fast wash-off. Otherwise, both the inner and outer gland in prostate cancer cases presented with high-intensitive enhancedment and slow wash-off. There was marked difference statistical significance on the up slop, average intensity and area under the time-intensity curves in 90 s and 150 s between the cases of BPH and prostate cancer (P<0.05, P<0.01). Conclusion: Quantitative analysis of high perfusion area in both inner and outer glands is helpful for diagnosing BPH and prostate cancer. (authors)

  14. Staff dosimetry and risk assessment during digestive and angiographic examinations

    Pages, J.; Osteaux, M.

    2001-01-01

    The use of ionizing radiation in medical applications involves not only a risk for the patient, but also for the staff which executed the related examinations. The dose to the forehead, neck, fingers and wrist of a radiologist and an assisting nurse were measured with thermoluminescent dosimeters during angiographic and digestive examinations respectively. Dose to eye lenses and effective dose were estimated for a working period of one year. Effective doses were under the established limit of 20 mSv per year. Nurse eye lens dose was higher than the limit of 150 mSv. Differences of a factor of 3.8 were observed between nurse and radiologist doses. Angiographic procedures are considered as high risk examinations, however, digestive examinations can have a higher risk than interventional procedures. (author)

  15. Development of DIGITEXαPlus digital angiographic system

    Imanishi, Tetsuo; Miura, Yusuke; Sasaki, Osamu; Furuyama, Makoto; Yasumi, Masayuki

    2001-01-01

    The functions required of digital angiographic (DA) systems have been noticeably changing with the recent popularization of the technique of interventional radiology (IVR) in the field of angiography. We have developed a new digital angiographic system, named the DIGITEXαPlus, which is designed to meet the requirements of the latest IVR technologies. The DIGITEXαPlus system is equipped with a high-performance one-million-pixel CCD camera, a newly developed F.P.O. (fluoro-power optimizer), and a contrast-priority radiography control system, which combine together to provide high quality of images both in fluoroscopy and in fluorography. In this new system, a low-dose pulsed fluoroscopy method, employed as standard, minimizes the X-ray doses to patients, and an image controller (IVR MASTER) of a joy stick type provides more diversified functions that its predecessors. These two features enhance the reliability, and simplifies the operation, of the IVR system as a whole. (author)

  16. A regret theory approach to decision curve analysis: A novel method for eliciting decision makers' preferences and decision-making

    Vickers Andrew; Hozo Iztok; Tsalatsanis Athanasios; Djulbegovic Benjamin

    2010-01-01

    Abstract Background Decision curve analysis (DCA) has been proposed as an alternative method for evaluation of diagnostic tests, prediction models, and molecular markers. However, DCA is based on expected utility theory, which has been routinely violated by decision makers. Decision-making is governed by intuition (system 1), and analytical, deliberative process (system 2), thus, rational decision-making should reflect both formal principles of rationality and intuition about good decisions. ...

  17. NEW REACTOR DESIGN AND ANALYSIS OF NON LINEAR VIBRATIONS OF DOUBLY CURVED SHALLOW SHELL UNDER A THERMAL GRADIENT

    Chanda, S.

    2004-01-01

    The present study concerns with the effects of material orthotropy,curvature, shear ratio and circumferential modulus under the influence of a temperature distribution throughout the shell structure. Here analysis is restricted to the study of nonlinear vibration of a doubly curved shell structure considering the periodic response of a simple bending mode due to curtailment of pages. Solutions of the problems with suitable illustrations are also presented

  18. Rapid Simultaneous Amplification and Detection of the MBR/JH Chromosomal Translocation by Fluorescence Melting Curve Analysis

    Bohling, Sandra D.; King, Thomas C.; Wittwer, Carl T.; Elenitoba-Johnson, Kojo S. J.

    1999-01-01

    Polymerase chain reaction (PCR) amplification and product analysis for the detection of chromosomal translocations, such as the t(14;18), has traditionally been a two-step process. PCR product detection has generally entailed gel electrophoresis and/or hybridization or sequencing for confirmation of assay specificity. Using a microvolume fluorimeter integrated with a thermal cycler and a PCR-compatible double-stranded DNA (dsDNA) binding fluorescent dye (SYBR Green I), we investigated the feasibility of simultaneous thermal amplification and detection of MBR/JH translocation products by fluorescence melting curve analysis. We analyzed DNA from 30 cases of lymphoproliferative disorders comprising 19 cases of previously documented MBR/JH-positive follicle center lymphoma and 11 reactive lymphadenopathies. The samples were coded and analyzed blindly for the presence of MBR/JH translocations by fluorescence melting curve analysis. We also performed dilutional assays using the MBR/JH-positive cell line SUDHL-6. Multiplex PCR for MBR/JH and β-globin was used to simultaneously assess sample adequacy. All (100%) of the 19 cases previously determined to be MBR/JH positive by conventional PCR analysis showed a characteristic sharp decrease in fluorescence at ∼90°C by melting curve analysis after amplification. Fluorescence melting peaks obtained by plotting the negative derivative of fluorescence over temperature (−dF/dT) versus temperature (T) showed melting temperatures (Tm) at 88.85 ± 1.15°C. In addition, multiplex assays using both MBR/JH and β-globin primers yielded easily distinguishable fluorescence melting peaks at ∼90°C and 81.2°C, respectively. Dilutional assays revealed that fluorescence melting curve analysis was more sensitive than conventional PCR and agarose gel electrophoresis with ultraviolet transillumination by as much as 100-fold. Simultaneous amplification and fluorescence melting curve analysis is a simple, reliable, and sensitive method

  19. AN ANALYSIS OF THE SHAPES OF INTERSTELLAR EXTINCTION CURVES. VI. THE NEAR-IR EXTINCTION LAW

    Fitzpatrick, E. L.; Massa, D.

    2009-01-01

    We combine new observations from the Hubble Space Telescope's Advanced Camera of Survey with existing data to investigate the wavelength dependence of near-IR (NIR) extinction. Previous studies suggest a power law form for NIR extinction, with a 'universal' value of the exponent, although some recent observations indicate that significant sight line-to-sight line variability may exist. We show that a power-law model for the NIR extinction provides an excellent fit to most extinction curves, but that the value of the power, β, varies significantly from sight line to sight line. Therefore, it seems that a 'universal NIR extinction law' is not possible. Instead, we find that as β decreases, R(V) ≡ A(V)/E(B - V) tends to increase, suggesting that NIR extinction curves which have been considered 'peculiar' may, in fact, be typical for different R(V) values. We show that the power-law parameters can depend on the wavelength interval used to derive them, with the β increasing as longer wavelengths are included. This result implies that extrapolating power-law fits to determine R(V) is unreliable. To avoid this problem, we adopt a different functional form for NIR extinction. This new form mimics a power law whose exponent increases with wavelength, has only two free parameters, can fit all of our curves over a longer wavelength baseline and to higher precision, and produces R(V) values which are consistent with independent estimates and commonly used methods for estimating R(V). Furthermore, unlike the power-law model, it gives R(V)s that are independent of the wavelength interval used to derive them. It also suggests that the relation R(V) = -1.36 E(K-V)/(E(B-V)) - 0.79 can estimate R(V) to ±0.12. Finally, we use model extinction curves to show that our extinction curves are in accord with theoretical expectations, and demonstrate how large samples of observational quantities can provide useful constraints on the grain properties.

  20. Analysis of variation in calibration curves for Kodak XV radiographic film using model-based parameters.

    Hsu, Shu-Hui; Kulasekere, Ravi; Roberson, Peter L

    2010-08-05

    Film calibration is time-consuming work when dose accuracy is essential while working in a range of photon scatter environments. This study uses the single-target single-hit model of film response to fit the calibration curves as a function of calibration method, processor condition, field size and depth. Kodak XV film was irradiated perpendicular to the beam axis in a solid water phantom. Standard calibration films (one dose point per film) were irradiated at 90 cm source-to-surface distance (SSD) for various doses (16-128 cGy), depths (0.2, 0.5, 1.5, 5, 10 cm) and field sizes (5 × 5, 10 × 10 and 20 × 20 cm²). The 8-field calibration method (eight dose points per film) was used as a reference for each experiment, taken at 95 cm SSD and 5 cm depth. The delivered doses were measured using an Attix parallel plate chamber for improved accuracy of dose estimation in the buildup region. Three fitting methods with one to three dose points per calibration curve were investigated for the field sizes of 5 × 5, 10 × 10 and 20 × 20 cm². The inter-day variation of model parameters (background, saturation and slope) were 1.8%, 5.7%, and 7.7% (1 σ) using the 8-field method. The saturation parameter ratio of standard to 8-field curves was 1.083 ± 0.005. The slope parameter ratio of standard to 8-field curves ranged from 0.99 to 1.05, depending on field size and depth. The slope parameter ratio decreases with increasing depth below 0.5 cm for the three field sizes. It increases with increasing depths above 0.5 cm. A calibration curve with one to three dose points fitted with the model is possible with 2% accuracy in film dosimetry for various irradiation conditions. The proposed fitting methods may reduce workload while providing energy dependence correction in radiographic film dosimetry. This study is limited to radiographic XV film with a Lumisys scanner.

  1. Persistent sciatic artery: clinical, embryologic, and angiographic features

    Mandell, V.S.; Jaques, P.F.; Delaney, D.J.; Oberheu, V.

    1985-01-01

    The persistent sciatic artery is a rare but interesting and clinically pertinent vascular anomaly that may present as a buttock aneurysm or as an ischemic or embolic disease. Its correct angiographic diagnosis depends on recognition of an abnormally large internal iliac artery, appropriate injection and adequate timing to fill and follow flow into the large vessel, and recognition and differentiation of the tapering superficial femoral artery from routine occlusive disease so that an accurate picture of lower leg runoff is provided

  2. IMPORTANCE OF KNOWING ANGIOGRAPHIC CHARACTERISTICS OF THE TENSOR FASCIAE LATAE VASCULAR STALK

    Sladjana Ugrenovic

    2006-07-01

    Full Text Available Atherosclerosis is the most important and most common type of arteriosclerosis and is a general term for several diseases in which the artery wall becomes thicker and less elastic. The most common location of atherosclerosis occurrence is arteries of lower extremities, while arteries of upper extremities as well as visceral arteries are far less and far rarely affected with this degenerative process.The most frequent ones are occlusive changes on bifurcation of the abdominal aorta (aortoiliac obstructive atherosclerosis “Morbus Leriche”, trunk of the femoral artery and initial part of the popliteal artery (femoropopliteal obstructive atherosclerosis.Angiography, as additional method in medicine, gives the most precise insight into anatomical changes on blood vessels. With intention of estimating the possibility of using a slice (lobe part of the tensor fasciae latae (m. TFL in plastic and reconstructive surgery, we have analyzed 50 angiograms of femoral artery. The first group included Morbus Leriche patients (25 analyzed angiographics, while the second one comprised patients with femoropopliteal segment disease (also 25 analyzed angiographics. With angiographic analysis of the lateral femoral circumflex artery (LCFA and its branch, which is dominant in vascularisation of m. TFL slice, we discovered that the diameter of its source, as well as of its branches, is bigger in cases of femoropopliteal segment disease. Then, the reduction of the source diameter of LCFA and its branches, caused by vascular disease, leads to decreased blood supply of m. TFL, diminishing its quality and limiting its usage in surgery.In Morbus Leriche cases, m. TFL slice cannot be used in plastic and reconstructive surgery, its quality being decreased, due to poor vascularization. In femoropopliteal segment disease cases, thanks to normal blood supply, m. TFL slice can be widely used for reconstructions or covering of defects, especially in inguinal region, which is

  3. DAG expression: high-throughput gene expression analysis of real-time PCR data using standard curves for relative quantification.

    María Ballester

    Full Text Available BACKGROUND: Real-time quantitative PCR (qPCR is still the gold-standard technique for gene-expression quantification. Recent technological advances of this method allow for the high-throughput gene-expression analysis, without the limitations of sample space and reagent used. However, non-commercial and user-friendly software for the management and analysis of these data is not available. RESULTS: The recently developed commercial microarrays allow for the drawing of standard curves of multiple assays using the same n-fold diluted samples. Data Analysis Gene (DAG Expression software has been developed to perform high-throughput gene-expression data analysis using standard curves for relative quantification and one or multiple reference genes for sample normalization. We discuss the application of DAG Expression in the analysis of data from an experiment performed with Fluidigm technology, in which 48 genes and 115 samples were measured. Furthermore, the quality of our analysis was tested and compared with other available methods. CONCLUSIONS: DAG Expression is a freely available software that permits the automated analysis and visualization of high-throughput qPCR. A detailed manual and a demo-experiment are provided within the DAG Expression software at http://www.dagexpression.com/dage.zip.

  4. Analysis of the static pressure volume curve of the lung in experimentally induced pulmonary damage by CT-densitometry

    David, M.; Karmrodt, J.; Herwelling, A.; Bletz, C.; David, S.; Heussel, C.P.; Markstaller, K.

    2005-01-01

    Purpose: To study quantitative changes of lung density distributions when recording in- and expiratory static pressure-volume curves by single slice computed tomography (CT). Materials and Methods: Static in- and expiratory pressure volume curves (0 to 1000 ml, increments of 100 ml) were obtained in random order in 10 pigs after induction of lung damage by saline lavage. Simultaneously, CT acquisitions (slice thickness 1 mm, temporal increment 2 s) were performed in a single slice (3 cm below the carina). In each CT image lung segmentation and planimetry of defined density ranges were achieved. The lung density ranges were defined as: hyperinflated (-1024 to -910 HU), normal aerated (-910 to -600 HU), poorly aerated (-600 to -300 HU), and non aerated (-300 to 200 HU) lung. Fractional areas of defined density ranges in percentage of total lung area were compared to recorded volume increments and airway pressures (atmospheric pressure, lower inflection point (LIP), LIP*0.5, LIP*1.5, peak airway pressure) of in- and expiratory pressure-volume curves. Results: Quantitative analysis of defined density ranges showed no differences between in- and expiratory pressure-volume curves. The amount of poorly aerated lung decreased and normal aerated lung increased constantly when airway pressure and volume were increased during inspiratory pressure-volume curves and vice versa during expiratory pressure-volume loops. Conclusion: Recruitment and derecruitment of lung atelectasis during registration of static in- and expiratory pressure-volume loops occurred constantly, but not in a stepwise manner. CT was shown to be an appropriate method to analyse these recruitment process. (orig.)

  5. Analysis of glow curves of TL readouts of CaSO4:Dy teflon based TLD badge in semiautomatic TLD badge reader

    Pradhan, S.M.; Sneha, C.; Adtani, M.M.

    2010-01-01

    The facility of glow curve storage and recall provided in the reader software is helpful for manual screening of the glow curves; however no further analysis is possible due to absence of numerical TL data at the sampling intervals. In the present study glow curves are digitized by modifying the reader software and then normalized to make them independent of the dose. The normalized glow curves are then analyzed by dividing them into five equal parts on time scale. This method of analysis is used to correlate the variation of total TL counts of the three discs with time elapsed post irradiation

  6. Learning Curve Analysis and Surgical Outcomes of Single-port Laparoscopic Myomectomy.

    Lee, Hee Jun; Kim, Ju Yeong; Kim, Seul Ki; Lee, Jung Ryeol; Suh, Chang Suk; Kim, Seok Hyun

    2015-01-01

    To identify learning curves for single-port laparoscopic myomectomy (SPLM) and evaluate surgical outcomes according to the sequence of operation. A retrospective study. A university-based hospital (Canadian Task Force classification II-2). The medical records from 205 patients who had undergone SPLM from October 2009 to May 2013 were reviewed. Because the myomectomy time was significantly affected by the size and number of myomas removed by SPLM, cases in which 2 or more of the myomas removed were >7 cm in diameter were excluded. Furthermore, cases involving additional operations performed simultaneously (e.g., ovarian or hysteroscopic surgery) were also excluded. A total of 161 cases of SPLM were included. None. We assessed the SPLM learning curve via a graph based on operation time versus sequence of cases. Patients were chronologically arranged according to their surgery dates and were then placed into 1 of 4 groups according to their operation sequence. SPLM was completed successfully in 160 of 161 cases (99.4%). One case was converted to multiport surgery. Basal characteristics of the patients between the 4 groups did not differ. The median operation times for the 4 groups were 112.0, 92.8, 83.7, and 90.0 minutes, respectively. Operation time decreased significantly in the second, third, and fourth groups compared with that in the first group (p learning curve became less steep, was evident after about 45 operations. Results from the current study suggested that proficiency for SPLM was achieved after about 45 operations. Additionally, operation time decreased with experience without an increase in complication rate. Copyright © 2015 AAGL. Published by Elsevier Inc. All rights reserved.

  7. Image Analysis of a Negatively Curved Graphitic Sheet Model for Amorphous Carbon

    Bursill, L. A.; Bourgeois, Laure N.

    High-resolution electron micrographs are presented which show essentially curved single sheets of graphitic carbon. Image calculations are then presented for the random surface schwarzite-related model of Townsend et al. (Phys. Rev. Lett. 69, 921-924, 1992). Comparison with experimental images does not rule out the contention that such models, containing surfaces of negative curvature, may be useful for predicting some physical properties of specific forms of nanoporous carbon. Some difficulties of the model predictions, when compared with the experimental images, are pointed out. The range of application of this model, as well as competing models, is discussed briefly.

  8. On-chip magnetic bead-based DNA melting curve analysis using a magnetoresistive sensor

    Rizzi, Giovanni; Østerberg, Frederik Westergaard; Henriksen, Anders Dahl

    2014-01-01

    We present real-time measurements of DNA melting curves in a chip-based system that detects the amount of surface-bound magnetic beads using magnetoresistive magnetic field sensors. The sensors detect the difference between the amount of beads bound to the top and bottom sensor branches....... The beads are magnetized by the field arising from the bias current passed through the sensors. We demonstrate the first on-chip measurements of the melting of DNA hybrids upon a ramping of the temperature. This overcomes the limitation of using a single washing condition at constant temperature. Moreover...

  9. Analysis of survival curves for Rhizopus, Mucor and Penicillia irradiated with gamma radiation

    Ishiguro, Etsuji; Danno, Akibumi; Miyazato, Mitsuru

    1994-01-01

    This study was aimed to understand the survival pattern of some microorganisms which were treated by γ-sterilization. Though most of the works were concentrated and reported with D 10 -values, it was presently found that the γ-irradiated survival curves showed sigmoid pattern and L-values were reached about half of the D 10 -value for each strains. It was further confirmed that if L-values were used for practical sterilization with D 10 -values, the estimation of sterilized levels would become more accurate. (author). 10 refs., 3 figs., 1 tab

  10. Similarity criterion analysis of dose-response curves in biological assay and radioimmunoassay of hormones

    Cristakou, H.D.

    1983-01-01

    The difficulties involved in the control of biological and radioimmunological assay systems, and in the maintenance of standard, as well as, the usual heterogeneity of assayed samples require some evidence of similarity between the dose-response curves obtained with the standard and the sample. Nowadays the parallelism test is used to provide such evidence. However, some indications of non-normal errors distribution, such as the presence of out layers, render the parallelism test both conceptually implausible and statistically inefficient. In such a manner we suggest the non-parametric 'frequencial' test as a more sounding option. (author)

  11. Barcoding melting curve analysis for rapid, sensitive, and discriminating authentication of saffron (Crocus sativus L.) from its adulterants.

    Jiang, Chao; Cao, Liang; Yuan, Yuan; Chen, Min; Jin, Yan; Huang, Luqi

    2014-01-01

    Saffron (Crocus sativus L.) is one of the most important and expensive medicinal spice products in the world. Because of its high market value and premium price, saffron is often adulterated through the incorporation of other materials, such as Carthamus tinctorius L. and Calendula officinalis L. flowers, Hemerocallis L. petals, Daucus carota L. fleshy root, Curcuma longa L. rhizomes, Zea may L., and Nelumbo nucifera Gaertn. stigmas. To develop a straightforward, nonsequencing method for rapid, sensitive, and discriminating detection of these adulterants in traded saffron, we report here the application of a barcoding melting curve analysis method (Bar-MCA) that uses the universal chloroplast plant DNA barcoding region trnH-psbA to identify adulterants. When amplified at DNA concentrations and annealing temperatures optimized for the curve analysis, peaks were formed at specific locations for saffron (81.92°C) and the adulterants: D. carota (81.60°C), C. tinctorius (80.10°C), C. officinalis (79.92°C), Dendranthema morifolium (Ramat.) Tzvel. (79.62°C), N. nucifera (80.58°C), Hemerocallis fulva (L.) L. (84.78°C), and Z. mays (84.33°C). The constructed melting curves for saffron and its adulterants have significantly different peak locations or shapes. In conclusion, Bar-MCA could be a faster and more cost-effective method to authenticate saffron and detect its adulterants.

  12. Barcoding Melting Curve Analysis for Rapid, Sensitive, and Discriminating Authentication of Saffron (Crocus sativus L. from Its Adulterants

    Chao Jiang

    2014-01-01

    Full Text Available Saffron (Crocus sativus L. is one of the most important and expensive medicinal spice products in the world. Because of its high market value and premium price, saffron is often adulterated through the incorporation of other materials, such as Carthamus tinctorius L. and Calendula officinalis L. flowers, Hemerocallis L. petals, Daucus carota L. fleshy root, Curcuma longa L. rhizomes, Zea may L., and Nelumbo nucifera Gaertn. stigmas. To develop a straightforward, nonsequencing method for rapid, sensitive, and discriminating detection of these adulterants in traded saffron, we report here the application of a barcoding melting curve analysis method (Bar-MCA that uses the universal chloroplast plant DNA barcoding region trnH-psbA to identify adulterants. When amplified at DNA concentrations and annealing temperatures optimized for the curve analysis, peaks were formed at specific locations for saffron (81.92°C and the adulterants: D. carota (81.60°C, C. tinctorius (80.10°C, C. officinalis (79.92°C, Dendranthema morifolium (Ramat. Tzvel. (79.62°C, N. nucifera (80.58°C, Hemerocallis fulva (L. L. (84.78°C, and Z. mays (84.33°C. The constructed melting curves for saffron and its adulterants have significantly different peak locations or shapes. In conclusion, Bar-MCA could be a faster and more cost-effective method to authenticate saffron and detect its adulterants.

  13. Clinical diagnostic accuracy of acute colonic diverticulitis in patients admitted with acute abdominal pain, a receiver operating characteristic curve analysis.

    Jamal Talabani, A; Endreseth, B H; Lydersen, S; Edna, T-H

    2017-01-01

    The study investigated the capability of clinical findings, temperature, C-reactive protein (CRP), and white blood cell (WBC) count to discern patients with acute colonic diverticulitis from all other patients admitted with acute abdominal pain. The probability of acute diverticulitis was assessed by the examining doctor, using a scale from 0 (zero probability) to 10 (100 % probability). Receiver operating characteristic (ROC) curves were used to assess the clinical diagnostic accuracy of acute colonic diverticulitis in patients admitted with acute abdominal pain. Of 833 patients admitted with acute abdominal pain, 95 had acute colonic diverticulitis. ROC curve analysis gave an area under the ROC curve (AUC) of 0.95 (CI 0.92 to 0.97) for ages patients. Separate analysis showed an AUC = 0.83 (CI 0.80 to 0.86) of CRP alone. White blood cell count and temperature were almost useless to discriminate acute colonic diverticulitis from other types of acute abdominal pain, AUC = 0.59 (CI 0.53 to 0.65) for white blood cell count and AUC = 0.57 (0.50 to 0.63) for temperature, respectively. This prospective study demonstrates that standard clinical evaluation by non-specialist doctors based on history, physical examination, and initial blood tests on admission provides a high degree of diagnostic precision in patients with acute colonic diverticulitis.

  14. Clinical and angiographic outcomes after intracoronary bare-metal stenting.

    I-Chang Hsieh

    Full Text Available BACKGROUND: Data from a large patient population regarding very long-term outcomes after BMS implantation are inadequate. This study aimed to evaluate the very long-term (8-17 years clinical and long-term (3-5 years angiographic outcomes after intracoronary bare-metal stenting (BMS. METHODS AND RESULTS: From the Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions (CAPTAIN registry, a total of 2391 patients with 2966 lesions treated with 3190 BMSs between November 1995 and May 2004 were evaluated. In total, 1898 patients with 2364 lesions, and 699 patients with 861 lesions underwent 6-month and 3- to 5- year angiographic follow-up, respectively. During a mean follow-up period of 149 ± 51 months, 18.6% of the patients died (including 10.8% due to cardiac death, 6.1% developed reinfarction, 16.2% had target lesion revascularization (including 81% of the patients within the first year, 14.5% underwent new lesion stenting (including 72% of the patients after 3 years, 2.4% underwent coronary bypass surgery, and 1.6% had definite stent thrombosis. The overall cardiovascular event-free survival rate was 58.5%. The 6-month angiographic study indicated a 20% restenosis rate. The minimal luminal diameter increased from 0.65 ± 0.44 mm to 3.02 ± 0.46 mm immediately after stenting, decreased to 2.06 ± 0.77 mm at the 6-month follow-up, and increased to 2.27 ± 0.68 mm at the 3- to 5-year follow-up. CONCLUSIONS: This study provides clinical and angiographic results from a large population of patients who underwent BMS implantations after a long-term follow-up period (149 ± 51 months. The progression of coronary atherosclerosis developed over time, and presented with new lesion required stent implantation. The follow-up angiographic findings reconfirmed the late and sustained improvement in luminal diameter between 6 months and 3-5 years.

  15. A disaggregated analysis of the environmental Kuznets curve for industrial CO_2 emissions in China

    Wang, Yuan; Zhang, Chen; Lu, Aitong; Li, Li; He, Yanmin; ToJo, Junji; Zhu, Xiaodong

    2017-01-01

    Highlights: • The existence of EKC hypothesis for industrial carbon emissions is tested for China. • A semi-parametric panel regression is used along with the STIRPAT model. • The validity of the EKC hypothesis varies across industry sectors. • The EKC relation to income exists in the electricity and heat production sector. • The EKC relation to urbanization exists in the manufacturing sector. - Abstract: The present study concentrates on a Chinese context and attempts to explicitly examine the impacts of economic growth and urbanization on various industrial carbon emissions through investigation of the existence of an environmental Kuznets curve. Within the Stochastic Impacts by Regression on Population, Affluence and Technology framework, this is the first attempt to simultaneously explore the income/urbanization and disaggregated industrial carbon dioxide emissions nexus, using panel data together with semi-parametric panel fixed effects regression. Our dataset is referred to a provincial panel of China spanning the period 2000–2013. With this information, we find evidence in support of an inverted U-shaped curve relationship between economic growth and carbon dioxide emissions in the electricity and heat production sector, but a similar inference only for urbanization and those emissions in the manufacturing sector. The heterogeneity in the EKC relationship across industry sectors implies that there is urgent need to design more specific policies related to carbon emissions reduction for various industry sectors. Also, these findings contribute to advancing the emerging literature on the development-pollution nexus.

  16. Neural network analysis of head-flow curves in deep well pumps

    Goelcue, Mustafa

    2006-01-01

    In impellers with splitter blades, the difficulty in calculation of the flow area of the impeller is because of the unknown flow rate occurring in the two separate areas when the splitter blades are added. Experimental studies were made to investigate the effects of splitter blade length on deep well pump performance for different numbers of blades. Head-flow curves of deep well pump impellers with splitter blades were investigated using artificial neural networks (ANNs). Gradient descent (GD), Gradient descent with momentum (GDM) and Levenberg-Marquardt (LM) learning algorithms were used in the networks. Experimental studies were completed to obtain training and test data. Blade number (z), non-dimensional splitter blade length (L-bar ) and flow rate (Q) were used as the input layer, while the output is head (H m ). For the testing data, the root mean squared error (RMSE), fraction of variance (R 2 ) and mean absolute percentage error (MAPE) were found to be 0.1285, 0.9999 and 1.6821%, respectively. With these results, we believe that the ANN can be used for prediction of head-flow curves as an appropriate method in deep well pump impellers with splitter blades.

  17. Non-regularized inversion method from light scattering applied to ferrofluid magnetization curves for magnetic size distribution analysis

    Rijssel, Jos van; Kuipers, Bonny W.M.; Erné, Ben H.

    2014-01-01

    A numerical inversion method known from the analysis of light scattering by colloidal dispersions is now applied to magnetization curves of ferrofluids. The distribution of magnetic particle sizes or dipole moments is determined without assuming that the distribution is unimodal or of a particular shape. The inversion method enforces positive number densities via a non-negative least squares procedure. It is tested successfully on experimental and simulated data for ferrofluid samples with known multimodal size distributions. The created computer program MINORIM is made available on the web. - Highlights: • A method from light scattering is applied to analyze ferrofluid magnetization curves. • A magnetic size distribution is obtained without prior assumption of its shape. • The method is tested successfully on ferrofluids with a known size distribution. • The practical limits of the method are explored with simulated data including noise. • This method is implemented in the program MINORIM, freely available online

  18. Application of Fourier Analysis to the ventricular volume curve in a digital system using radioisotopic vetricylography. Study of the diastolic function

    Ricke, F.; Gonzalez, P.; Pruzzo, R.; Nagel, J.

    1987-01-01

    To assess diastolic and systolic ventricular function, a computerized method was developed using Fourier analysis on left ventricular time activity curves. The ventricular raw curve obtained from radionuclide gate blood pool imaging was substituted by a four harmonics curve. Valuable parameters were then calculated specially peak ejection rate, filling fraction and peak filling rate, which allowed clear-cut differentiation normal subjects from patients with left ventricular hypertrophy. (author)

  19. Corrected thrombolysis in myocardial infarction frame counts in diabetic patients with angiographically normal coronary arteries

    Turkoglu, S.; Ozdemir, M.; Tacoy, G.; Tavil, Y.; Abaci, A.; Timurkaynak, T.; Cengel, A.

    2008-01-01

    Objective was to evaluate corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) in patients with angiographically normal coronary arteries and diabetes mellitus, a condition known to be associated with microvascular dysfunction. Patients who underwent coronary angiography in Gazi University Hospital, Ankara, Turkey between January 2000 and January 2005 were studied. Corrected TIMI frame count was left circumflex (Cx) and right coronary arteries (RCA) in 118 diabetic and 122 non-diabetic patients with normal coronary angiogram. The mean CTFC values of the LAD, Cx and the RCA were similar in diabetics and nondiabetics (21.0+-7.5 versus 21.3+-9.6, 23.3+-9.7 versus 23.5+-10.8, 17.9+-6.7 versus 18.7+-7.4 respectively, p>0.05 for all comparisons). In stepwise multivariate linear regression analysis, body surface area had a significant correlation with CTFC of all the 3 coronary arteries. We conclude that CTFC in diabetics and non-diabetics with angiographically normal coronary arteries is similar. Since microvascular disease is an inherent component of diabetes, our finding may reflect the inadequacy of CTFC in predicting microvascular disease in diabetic patients with normal coronary angiograms. (author)

  20. Spectral analysis of the IntCal98 calibration curve: a Bayesian view

    Palonen, V.; Tikkanen, P.

    2004-01-01

    Preliminary results from a Bayesian approach to find periodicities in the IntCal98 calibration curve are given. It has been shown in the literature that the discrete Fourier transform (Schuster periodogram) corresponds to the use of an approximate Bayesian model of one harmonic frequency and Gaussian noise. Advantages of the Bayesian approach include the possibility to use models for variable, attenuated and multiple frequencies, the capability to analyze unevenly spaced data and the possibility to assess the significance and uncertainties of spectral estimates. In this work, a new Bayesian model using random walk noise to take care of the trend in the data is developed. Both Bayesian models are described and the first results of the new model are reported and compared with results from straightforward discrete-Fourier-transform and maximum-entropy-method spectral analyses

  1. Parent Prevention Communication Profiles and Adolescent Substance Use: A Latent Profile Analysis and Growth Curve Model

    Choi, Hye Jeong; Miller-Day, Michelle; Shin, YoungJu; Hecht, Michael L.; Pettigrew, Jonathan; Krieger, Janice L.; Lee, JeongKyu; Graham, John W.

    2017-01-01

    This current study identifies distinct parent prevention communication profiles and examines whether youth with different parental communication profiles have varying substance use trajectories over time. Eleven schools in two rural school districts in the Midwestern United States were selected, and 784 students were surveyed at three time points from the beginning of 7th grade to the end of 8th grade. A series of latent profile analyses were performed to identify discrete profiles/subgroups of substance-specific prevention communication (SSPC). The results revealed a 4-profile model of SSPC: Active-Open, Passive-Open, Active-Silent, and Passive-Silent. A growth curve model revealed different rates of lifetime substance use depending on the youth’s SSPC profile. These findings have implications for parenting interventions and tailoring messages for parents to fit specific SSPC profiles. PMID:29056872

  2. Stress-strain curve of concretes with recycled concrete aggregates: analysis of the NBR 8522 methodology

    D. A. GUJEL

    Full Text Available ABSTRACT This work analyses the methodology "A" (item A.4 employed by the Brazilian Standard ABNT 8522 (ABNT, 2008 for determining the stress-strain behavior of cylindrical specimens of concrete, presenting considerations about possible enhancements aiming it use for concretes with recycled aggregates with automatic test equipment. The methodology specified by the Brazilian Standard presents methodological issues that brings distortions in obtaining the stress-strain curve, as the use of a very limited number of sampling points and by inducing micro cracks and fluency in the elastic behavior of the material due to the use of steady stress levels in the test. The use of a base stress of 0.5 MPa is too low for modern high load test machines designed do high strength concrete test. The work presents a discussion over these subjects, and a proposal of a modified test procedure to avoid such situations.

  3. ROC curve analyses of eyewitness identification decisions: An analysis of the recent debate.

    Rotello, Caren M; Chen, Tina

    2016-01-01

    How should the accuracy of eyewitness identification decisions be measured, so that best practices for identification can be determined? This fundamental question is under intense debate. One side advocates for continued use of a traditional measure of identification accuracy, known as the diagnosticity ratio , whereas the other side argues that receiver operating characteristic curves (ROCs) should be used instead because diagnosticity is confounded with response bias. Diagnosticity proponents have offered several criticisms of ROCs, which we show are either false or irrelevant to the assessment of eyewitness accuracy. We also show that, like diagnosticity, Bayesian measures of identification accuracy confound response bias with witnesses' ability to discriminate guilty from innocent suspects. ROCs are an essential tool for distinguishing memory-based processes from decisional aspects of a response; simulations of different possible identification tasks and response strategies show that they offer important constraints on theory development.

  4. From curve fitting to machine learning an illustrative guide to scientific data analysis and computational intelligence

    Zielesny, Achim

    2016-01-01

    This successful book provides in its second edition an interactive and illustrative guide from two-dimensional curve fitting to multidimensional clustering and machine learning with neural networks or support vector machines. Along the way topics like mathematical optimization or evolutionary algorithms are touched. All concepts and ideas are outlined in a clear cut manner with graphically depicted plausibility arguments and a little elementary mathematics. The major topics are extensively outlined with exploratory examples and applications. The primary goal is to be as illustrative as possible without hiding problems and pitfalls but to address them. The character of an illustrative cookbook is complemented with specific sections that address more fundamental questions like the relation between machine learning and human intelligence. All topics are completely demonstrated with the computing platform Mathematica and the Computational Intelligence Packages (CIP), a high-level function library developed with M...

  5. High resolution melt curve analysis based on methylation status for human semen identification.

    Fachet, Caitlyn; Quarino, Lawrence; Karnas, K Joy

    2017-03-01

    A high resolution melt curve assay to differentiate semen from blood, saliva, urine, and vaginal fluid based on methylation status at the Dapper Isoform 1 (DACT1) gene was developed. Stains made from blood, saliva, urine, semen, and vaginal fluid were obtained from volunteers and DNA was isolated using either organic extraction (saliva, urine, and vaginal fluid) or Chelex ® 100 extraction (blood and semen). Extracts were then subjected to bisulfite modification in order to convert unmethylated cytosines to uracil, consequently creating sequences whose amplicons have melt curves that vary depending on their initial methylation status. When primers designed to amplify the promoter region of the DACT1 gene were used, DNA from semen samples was distinguishable from other fluids by a having a statistically significant lower melting temperature. The assay was found to be sperm-significant since semen from a vasectomized man produced a melting temperature similar to the non-semen body fluids. Blood and semen stains stored up to 5 months and tested at various intervals showed little variation in melt temperature indicating the methylation status was stable during the course of the study. The assay is a more viable method for forensic science practice than most molecular-based methods for body fluid stain identification since it is time efficient and utilizes instrumentation common to forensic biology laboratories. In addition, the assay is advantageous over traditional presumptive chemical methods for body fluid identification since results are confirmatory and the assay offers the possibility of multiplexing which may test for multiple body fluids simultaneously.

  6. Transit Timing Variation analysis with Kepler light curves of KOI 227 and Kepler 93b

    Dulz, Shannon; Reed, Mike

    2017-01-01

    By searching for transit signals in approximately 150,000 stars, NASA’s Kepler Space telescope found thousands of exoplanets over its primary mission from 2009 to 2013 (Tenenbaum et al. 2014, ApJS, 211, 6). Yet, a detailed follow-up examination of Kepler light curves may contribute more evidence on system dynamics and planetary atmospheres of these objects. Kepler’s continuous observing of these systems over the mission duration produced light curves of sufficient duration to allow for the search for transit timing variations. Transit timing variations over the course of many orbits may indicate a precessing orbit or the existence of a non-transiting third body such as another exoplanet. Flux contributions of the planet just prior to secondary eclipse may provide a measurement of bond albedo from the day-side of the transiting planet. Any asymmetries of the transit shape may indicate thermal asymmetries which can measure upper atmosphere motion of the planet. These two factors can constrain atmospheric models of close orbiting exoplanets. We first establish our procedure with the well-documented TTV system, KOI 227 (Nesvorny et al. 2014, ApJ, 790, 31). Using the test case of KOI 227, we analyze Kepler-93b for TTVs and day-side flux contributions. Kepler-93b is likely a rocky planet with R = 1.50 ± 0.03 Earth Radii and M = 2.59 ± 2.0 Earth Masses (Marcy et al. 2014, ApJS, 210, 20). This research is funded by a NASA EPSCoR grant.

  7. CFD and Thermo Mechanical Analysis on Effect of Curved vs Step Surface in IC Engine Cylinder Head

    Balaji, S.; Ganesh, N.; Kumarasamy, A.

    2017-05-01

    Current research in IC engines mainly focus on various methods to achieve higher efficiency and high specific power. As a single design parameter, combustion chamber peak spring pressure has increased more than before. Apart from the structural aspects of withstanding these loads, designer faces challenges of resolving thermal aspects of cylinder head. Methods to enhance the heat transfer without compromising load withstanding capability are being constantly explored. Conventional cylinder heads have got sat inner surface. In this paper we have suggested a modification in inner surface to enhance the heat transfer capability. To increase the heat transfer rate, inner same deck surface is configured as a curved and stepped surface instead of sat. We have reported the effectiveness of extend of curvature in the inner same deck surface in a different technical paper. Here, we are making a direct comparison between stepped and curved surface only. From this analysis it has been observed that curved surface reduces the ame deck temperature considerably without compromising the structural strength factors compared to step and sat surface.

  8. Simultaneous detection of Fusarium culmorum and F. graminearum in plant material by duplex PCR with melting curve analysis.

    Brandfass, Christoph; Karlovsky, Petr

    2006-01-23

    Fusarium head blight (FHB) is a disease of cereal crops, which has a severe impact on wheat and barley production worldwide. Apart from reducing the yield and impairing grain quality, FHB leads to contamination of grain with toxic secondary metabolites (mycotoxins), which pose a health risk to humans and livestock. The Fusarium species primarily involved in FHB are F. graminearum and F. culmorum. A key prerequisite for a reduction in the incidence of FHB is an understanding of its epidemiology. We describe a duplex-PCR-based method for the simultaneous detection of F. culmorum and F. graminearum in plant material. Species-specific PCR products are identified by melting curve analysis performed in a real-time thermocycler in the presence of the fluorescent dye SYBR Green I. In contrast to multiplex real-time PCR assays, the method does not use doubly labeled hybridization probes. PCR with product differentiation by melting curve analysis offers a cost-effective means of qualitative analysis for the presence of F. culmorum and F. graminearum in plant material. This method is particularly suitable for epidemiological studies involving a large number of samples.

  9. Simultaneous detection of Fusarium culmorum and F. graminearum in plant material by duplex PCR with melting curve analysis

    Karlovsky Petr

    2006-01-01

    Full Text Available Abstract Background Fusarium head blight (FHB is a disease of cereal crops, which has a severe impact on wheat and barley production worldwide. Apart from reducing the yield and impairing grain quality, FHB leads to contamination of grain with toxic secondary metabolites (mycotoxins, which pose a health risk to humans and livestock. The Fusarium species primarily involved in FHB are F. graminearum and F. culmorum. A key prerequisite for a reduction in the incidence of FHB is an understanding of its epidemiology. Results We describe a duplex-PCR-based method for the simultaneous detection of F. culmorum and F. graminearum in plant material. Species-specific PCR products are identified by melting curve analysis performed in a real-time thermocycler in the presence of the fluorescent dye SYBR Green I. In contrast to multiplex real-time PCR assays, the method does not use doubly labeled hybridization probes. Conclusion PCR with product differentiation by melting curve analysis offers a cost-effective means of qualitative analysis for the presence of F. culmorum and F. graminearum in plant material. This method is particularly suitable for epidemiological studies involving a large number of samples.

  10. Economic growth and environmental pollution in Myanmar: an analysis of environmental Kuznets curve.

    Aung, Thiri Shwesin; Saboori, Behnaz; Rasoulinezhad, Ehsan

    2017-09-01

    This empirical study examines the short- and long-run relationship between GDP as an economic growth indicator and CO 2 emissions as an environmental pollution indicator in Myanmar by using annual time series data over the period of 1970-2014. It also carefully considered other proxies, such as trade openness, financial openness and urbanization, and structural breaks in the country. The fundamental objective of this study is to test the validity of environmental Kuznets curve (EKC) in the context of Myanmar. The dynamic estimates of the long- and short-term relationship among greenhouse gases (CO 2 , CH 4 , N 2 O), GDP, trade intensity, financial openness, and urbanization growth are built through an autoregressive distributed lag (ARDL) model. The empirical findings indicate that there is positive short- and long-run relationship between CO 2 and GDP and thus, no evidence of EKC hypothesis is found for CO 2 in Myanmar. Nevertheless, the existence of the EKC is observed for CH 4 and N 2 O. On the other hand, trade and financial openness have inverse relationship with CO 2 emissions. These results demonstrate that trade liberalization and financial openness will improve the environment quality in Myanmar in the long run.

  11. Numerical analysis of thermal creep flow in curved channels for designing a prototype of Knudsen micropump

    Leontidis, V; Baldas, L; Colin, S; Brandner, J J

    2012-01-01

    The possibility to generate a gas flow inside a channel just by imposing a tangential temperature gradient along the walls without the existence of an initial pressure difference is well known. The gas must be under rarefied conditions, meaning that the system must operate between the slip and the free molecular flow regimes, either at low pressure or/and at micro/nano-scale dimensions. This phenomenon is at the basis of the operation principle of Knudsen pumps, which are actually compressors without any moving parts. Nowadays, gas flows in the slip flow regime through microchannels can be modeled using commercial Computational Fluid Dynamics softwares, because in this regime the compressible Navier-Stokes equations with appropriate boundary conditions are still valid. A simulation procedure has been developed for the modeling of thermal creep flow using ANSYS Fluent®. The implementation of the boundary conditions is achieved by developing User Defined Functions (UDFs) by means of C++ routines. The complete first order velocity slip boundary condition, including the thermal creep effects due to the axial temperature gradient and the effect of the wall curvature, and the temperature jump boundary condition are applied. The developed simulation tool is used for the preliminary design of Knudsen micropumps consisting of a sequence of curved and straight channels.

  12. Luminescence characteristics and glow curves analysis of Cu"+ doped Li_3PO_4 phosphor

    Aghalte, G.A.; Dhoble, S.J.; Pawar, N.R.

    2016-01-01

    Li_3PO_4:Cu exhibits useful TL properties in personnel dosimetry of ionizing radiations. Cu is known to be one of the most efficient activator. The PL intensity is found to increase consistently with the increasing quenching temperature. Cu"+ doped Li_3PO_4 phosphor was synthesized by the wet chemical co-precipitation method. The crystal structure and particle morphology of the phosphor was investigated by using X-ray diffraction and scanning electron microscopy. Li_3PO_4:Cu is excellent phosphor for TL dosimetry. For the synthesis of Li_3PO_4:Cu phosphor the stoichiometric amounts of LiOH·H_2O and CuSO_4·"5H_2O were dissolved separately and then the solutions were mixed together. It was precipitated by using concentrated H_3PO_4. The precipitate was filtered out immediately and kept 12 hours below IR lamp. Prepared dry Li_3PO_4:Cu powder was then put on 2.5 wt% NH_4Cl in graphite crucible in preheated furnace at 800°C and was kept for 1 hour. It was then rapidly quenched to room temperature. Thermoluminescence (TL) glow curves were recorded on Nucleonix TL Reader with a heating rate of 2°C per second in the temperature range of 50-250°C. The PMT voltage was 750 volts. Photoluminescence (PL) studies were carried out by Hitachi F-4000 spectrophotometer with a spectral slit width of 1.5 nm

  13. Experimental analysis of the power curve sensitivity test series at ROSA-III

    Koizumi, Y.; Iriko, M.; Yonomoto, T.; Tasaka, K.

    1985-01-01

    The rig of safety assessment (ROSA)-III facility is a volumetrically scaled (1/424) boiling water reactor (BWR/6) system with an electrically heated core designed for integral LOCA and ECCS tests. Seven recirculation pump suction line break LOCA experiments were conducted at the ROSA-III facility in order to examine the effect of the initial stored heat of a fuel rod on the peak cladding temperature (PCT). The break size was changed from 200% to 5% in the test series and a failure of a high pressure core spray (HPCS) diesel generator was assumed. Three power curves which represented conservative, realistic and zero initial stored heat, respectively, were used. In a large break LOCA such as 200% or 50% breaks, the initial stored heat in a fuel rod has a large effect on the cladding surface temperature because core uncovery occurs before all the initial stored heat is released, whereas in a small break LOCA such as a 5% break little effect is observed because core uncovery occurs after the initial stored heat is released. The maximum PCTs for the conservative initial stored heat case was 925 K, obtained in the 50% break experiment, and that for the realistic initial stored heat case was 835 K, obtained in the 5% break experiment. (orig./HP)

  14. On-chip magnetic bead-based DNA melting curve analysis using a magnetoresistive sensor

    Rizzi, Giovanni; Østerberg, Frederik W.; Henriksen, Anders D.; Dufva, Martin; Hansen, Mikkel F.

    2015-01-01

    We present real-time measurements of DNA melting curves in a chip-based system that detects the amount of surface-bound magnetic beads using magnetoresistive magnetic field sensors. The sensors detect the difference between the amount of beads bound to the top and bottom sensor branches of the differential sensor geometry. The sensor surfaces are functionalized with wild type (WT) and mutant type (MT) capture probes, differing by a single base insertion (a single nucleotide polymorphism, SNP). Complementary biotinylated targets in suspension couple streptavidin magnetic beads to the sensor surface. The beads are magnetized by the field arising from the bias current passed through the sensors. We demonstrate the first on-chip measurements of the melting of DNA hybrids upon a ramping of the temperature. This overcomes the limitation of using a single washing condition at constant temperature. Moreover, we demonstrate that a single sensor bridge can be used to genotype a SNP. - Highlights: • We apply magnetoresistive sensors to study solid-surface hybridization kinetics of DNA. • We measure DNA melting profiles for perfectly matching DNA duplexes and for a single base mismatch. • We present a procedure to correct for temperature dependencies of the sensor output. • We reliably extract melting temperatures for the DNA hybrids. • We demonstrate direct measurement of differential binding signal for two probes on a single sensor

  15. Post-Buckling Analysis of Curved Honeycomb Sandwich Panels Containing Interfacial Disbonds

    Pineda, Evan J.; Bednarcyk, Brett A.; Krivanek, Thomas K.

    2016-01-01

    A numerical study on the effect of facesheet-core disbonds on the post-buckling response of curved honeycomb sandwich panels is presented herein. This work was conducted as part of the development of a damage tolerance plan for the next-generation Space Launch System heavy lift launch vehicle payload fairing. As such, the study utilized full-scale fairing barrel segments as the structure of interest. The panels were composed of carbon fiber reinforced polymer facesheets and aluminum honeycomb core. The panels were analyzed numerically using the finite element method incorporating geometric nonlinearity. In a predetermined circular region, facesheet and core nodes were detached to simulate a disbond, between the outer mold line facesheet and honeycomb core, induced via low-speed impact. Surface-to-surface contact in the disbonded region was invoked to prevent interpenetration of the facesheet and core elements and obtain realistic stresses in the core. The diameter of this disbonded region was varied and the effect of the size of the disbond on the post-buckling response was observed. Significant changes in the slope of the edge load-deflection response were used to determine the onset of global buckling and corresponding buckling load. Finally, several studies were conducted to determine the sensitivity of the numerical predictions to refinement in the finite element mesh.

  16. Environmental Kuznets Curve in China: New evidence from dynamic panel analysis

    Li, Tingting; Wang, Yong; Zhao, Dingtao

    2016-01-01

    This paper applies a panel of 28 provinces of China from 1996 to 2012 to study the impacts of economic development, energy consumption, trade openness, and urbanization on the carbon dioxide, waste water, and waste solid emissions. By estimating a dynamic panel model with the system Generalized Method of Moments (GMM) estimator and an autoregressive distributed lag (ARDL) model with alternative panel estimators, respectively, we find that the Environmental Kuznets Curve (EKC) hypothesis is well supported for all three major pollutant emissions in China across different models and estimation methods. Our study also confirms positive effects of energy consumption on various pollutant emissions. In addition, we find some evidence that trade and urbanization may deteriorate environmental quality in the long run, albeit not in the short run. From policy perspective, our estimation results bode well for Chinese government's goal of capping greenhouse emissions by 2030 as outlined in the recent China-US climate accord, while containing energy consumption and harm effects from expanding trade and urbanization remains some environmental challenges that China faces. - Highlights: •We apply dynamic panel estimations to study the EKC hypothesis with Chinese panel data. •Our study covers three indicators: carbon dioxide, waste water, and waste solid emissions. •We find robust support for the EKC hypothesis for all three indicators of pollution. •Energy consumption has significantly positive effects on all three pollutant emissions. •Trade and urbanization may have harmful environmental impacts in the long run.

  17. Analysis of the Validity of Environmental Kuznets Curve for the Baltic States

    Lapinskienė, Giedrė; Tvaronavičienė, Manuela; Vaitkus, Pranas

    2013-12-01

    The paper analyses a traditional Environmental Kuznets Curve (EKC) relationship between greenhouse gases (GHG) and gross domestic product (GDP), extending the research to include some additional factors, such as environmental tax, research and development expenditure, implicit tax rate on energy, primary production of coal and lignite, energy intensity of the economy taken from the Eurostat database. The EKC indicates that, at the early stages of economic growth, pollution increases with the growing use of resources, but when a certain level of income per capita is reached, the trend reverses so that, at a higher development stage, further economic growth leads to the improvement of the environment. In the first part of the research, the validity of the reduced EKC for the Baltic region for the period 1995-2008 is determined. In the second part, the impact of selected factors is statistically tested. In both cases, the standard cubic equation is used because it is believed that this model is the most accurate for the development stage of this region. The research results may be useful for climate change policy design.

  18. Angiographic Guidewire with Measuring Markers: Design and Clinical Experience

    Kamei, Seiji; Ishiguchi, Tsuneo; Murata, Katsuhito; Matsuda, Joe; Ohno, Ryota; Kimura, Junko; Nakamura, Atsushi; Ohno, Kazuko; Kawamura, Toshiki; Ikeda, Mitsuru

    2006-01-01

    Purpose. We have developed an angiographic guidewire with measuring markers to determine accurately how far a guidewire is inserted within a catheter. We investigated whether use of this guidewire reduces the risk of vascular injury and the fluoroscopic time during guidewire manipulations. Methods. Four markers were put on the surface of the guidewire at 80, 100, 110, and 120 cm from the tip. The actual lengths of 54 catheters from seven manufacturers were measured and compared with the nominal lengths. Sixty consecutive patients who underwent angiography were randomized into two groups: in one group guidewires with surface markers were used (marker group) and in the other group, conventional guidewires (control group). For each guidewire insertion, the fluoroscopic time before the guidewire was pushed forward into the vessel lumen was recorded. The number of occasions on which unintentionally the guidewire had already been pushed out of the catheter at the start of fluoroscopy was also evaluated. Results. The actual lengths of all catheters were greater than the nominal lengths by 1.0-11.0 cm. Mean fluoroscopic time for each guidewire insertion was 3.3 sec in the marker group and 5.7 sec in the control group (p < 0.05). Guidewires were unintentionally pushed out of the catheters without fluoroscopy three times (3.6%), in each case in the control group. Conclusion. The guidewire with measuring markers is effective for enhancing safety and in reducing fluoroscopic radiation during angiographic procedures. It is recommended that operators be aware that actual lengths of catheters may vary significantly from the nominal lengths listed; they should be aware of this with any guidewire, but particularly with the angiographic measuring guidewire

  19. Clinical-pathological-angiographic correlations following transluminal atherectomy

    Althaus, S.J.; Maynar, M.; Reyes, R.; Pulido-Duque, J.M.; Casal, G.; Hunter, D.W.; Castaneda-Zuniga, W.R.; Amplatz, K.

    1989-01-01

    Following percutaneous atherectomy, arterial and catheter diameter relationships were correlated with angiographic and ankle-arm index results. There was a greater amount of tissue removed, improved luminal reconstitution, and ankle-arm index in lesions where the catheter and arterial diameters were equal or within 0.5 mm. Excluding lesions requiring angioplasty, 77% of our lesions had less than 30% residual stenosis; including lesions requiring concomitant angioplasty, the initial overall patency was 93%, with a 1-year patency rate of 92.5%. This study indicates that adequate matching of the atherectomy catheter diameter to the arterial diameter is necessary to optimize tissue removal and clinical results

  20. Effective dose and dose to crystalline lens during angiographic procedures

    Pages, J.

    1998-01-01

    The highest radiation doses levels received by radiologists are observed during interventional procedures. Doses to forehead and neck received by a radiologist executing angiographic examinations at the department of radiology at the academic hospital (AZ-VUB) have been measured for a group of 34 examinations. The doses to crystalline lens and the effective doses for a period of one year have been estimated. For the crystalline lens the maximum dose approaches the ICRP limit, that indicates the necessity for the radiologist to use leaded glasses. (N.C.)

  1. Systematic review of learning curves for minimally invasive abdominal surgery: a review of the methodology of data collection, depiction of outcomes, and statistical analysis.

    Harrysson, Iliana J; Cook, Jonathan; Sirimanna, Pramudith; Feldman, Liane S; Darzi, Ara; Aggarwal, Rajesh

    2014-07-01

    To determine how minimally invasive surgical learning curves are assessed and define an ideal framework for this assessment. Learning curves have implications for training and adoption of new procedures and devices. In 2000, a review of the learning curve literature was done by Ramsay et al and it called for improved reporting and statistical evaluation of learning curves. Since then, a body of literature is emerging on learning curves but the presentation and analysis vary. A systematic search was performed of MEDLINE, EMBASE, ISI Web of Science, ERIC, and the Cochrane Library from 1985 to August 2012. The inclusion criteria are minimally invasive abdominal surgery formally analyzing the learning curve and English language. 592 (11.1%) of the identified studies met the selection criteria. Time is the most commonly used proxy for the learning curve (508, 86%). Intraoperative outcomes were used in 316 (53%) of the articles, postoperative outcomes in 306 (52%), technical skills in 102 (17%), and patient-oriented outcomes in 38 (6%) articles. Over time, there was evidence of an increase in the relative amount of laparoscopic and robotic studies (P statistical evidence of a change in the complexity of analysis (P = 0.121). Assessment of learning curves is needed to inform surgical training and evaluate new clinical procedures. An ideal analysis would account for the degree of complexity of individual cases and the inherent differences between surgeons. There is no single proxy that best represents the success of surgery, and hence multiple outcomes should be collected.

  2. Scenario analysis for estimating the learning rate of photovoltaic power generation based on learning curve theory in South Korea

    Hong, Sungjun; Chung, Yanghon; Woo, Chungwon

    2015-01-01

    South Korea, as the 9th largest energy consuming in 2013 and the 7th largest greenhouse gas emitting country in 2011, established ‘Low Carbon Green Growth’ as the national vision in 2008, and is announcing various active energy policies that are set to gain the attention of the world. In this paper, we estimated the decrease of photovoltaic power generation cost in Korea based on the learning curve theory. Photovoltaic energy is one of the leading renewable energy sources, and countries all over the world are currently expanding R and D, demonstration and deployment of photovoltaic technology. In order to estimate the learning rate of photovoltaic energy in Korea, both conventional 1FLC (one-factor learning curve), which considers only the cumulative power generation, and 2FLC, which also considers R and D investment were applied. The 1FLC analysis showed that the cost of power generation decreased by 3.1% as the cumulative power generation doubled. The 2FCL analysis presented that the cost decreases by 2.33% every time the cumulative photovoltaic power generation is doubled and by 5.13% every time R and D investment is doubled. Moreover, the effect of R and D investment on photovoltaic technology took after around 3 years, and the depreciation rate of R and D investment was around 20%. - Highlights: • We analyze the learning effects of photovoltaic energy technology in Korea. • In order to calculate the learning rate, we use 1FLC (one-factor learning curve) and 2FLC methods, respectively. • 1FLC method considers only the cumulative power generation. • 2FLC method considers both cumulative power generation and knowledge stock. • We analyze a variety of scenarios by time lag and depreciation rate of R and D investment

  3. Rapid screening for targeted genetic variants via high-resolution melting curve analysis.

    Chambliss, Allison B; Resnick, Molly; Petrides, Athena K; Clarke, William A; Marzinke, Mark A

    2017-03-01

    Current methods for the detection of single nucleotide polymorphisms (SNPs) associated with aberrant drug-metabolizing enzyme function are hindered by long turnaround times and specialized techniques and instrumentation. In this study, we describe the development and validation of a high-resolution melting (HRM) curve assay for the rapid screening of variant genotypes for targeted genetic polymorphisms in the cytochrome P450 enzymes CYP2C9, CYP2C19, and CYP3A5. Sequence-specific primers were custom-designed to flank nine SNPs within the genetic regions of aforementioned drug metabolizing enzymes. PCR amplification was performed followed by amplicon denaturation by precise temperature ramping in order to distinguish genotypes by melting temperature (Tm). A standardized software algorithm was used to assign amplicons as 'reference' or 'variant' as compared to duplicate reference sequence DNA controls for each SNP. Intra-assay (n=5) precision of Tms for all SNPs was ≤0.19%, while inter-assay (n=20) precision ranged from 0.04% to 0.21%. When compared to a reference method of Sanger sequencing, the HRM assay produced no false negative results, and overcall frequency ranged from 0% to 26%, depending on the SNP. Furthermore, HRM genotyping displayed accuracy over input DNA concentrations ranging from 10 to 200 ng/μL. The presented assay provides a rapid method for the screening for genetic variants in targeted CYP450 regions with a result of 'reference' or 'variant' available within 2 h from receipt of extracted DNA. The method can serve as a screening approach to rapidly identify individuals with variant sequences who should be further investigated by reflexed confirmatory testing for aberrant cytochrome P450 enzymatic activity. Rapid knowledge of variant status may aid in the avoidance of adverse clinical events by allowing for dosing of normal metabolizer patients immediately while identifying the need to wait for confirmatory testing in those patients who are

  4. Parameter sensitivity analysis of the mixed Green-Ampt/Curve-Number method for rainfall excess estimation in small ungauged catchments

    Romano, N.; Petroselli, A.; Grimaldi, S.

    2012-04-01

    With the aim of combining the practical advantages of the Soil Conservation Service - Curve Number (SCS-CN) method and Green-Ampt (GA) infiltration model, we have developed a mixed procedure, which is referred to as CN4GA (Curve Number for Green-Ampt). The basic concept is that, for a given storm, the computed SCS-CN total net rainfall amount is used to calibrate the soil hydraulic conductivity parameter of the Green-Ampt model so as to distribute in time the information provided by the SCS-CN method. In a previous contribution, the proposed mixed procedure was evaluated on 100 observed events showing encouraging results. In this study, a sensitivity analysis is carried out to further explore the feasibility of applying the CN4GA tool in small ungauged catchments. The proposed mixed procedure constrains the GA model with boundary and initial conditions so that the GA soil hydraulic parameters are expected to be insensitive toward the net hyetograph peak. To verify and evaluate this behaviour, synthetic design hyetograph and synthetic rainfall time series are selected and used in a Monte Carlo analysis. The results are encouraging and confirm that the parameter variability makes the proposed method an appropriate tool for hydrologic predictions in ungauged catchments. Keywords: SCS-CN method, Green-Ampt method, rainfall excess, ungauged basins, design hydrograph, rainfall-runoff modelling.

  5. Surgical Management of Juvenile Nasopharyngeal Angiofibroma Without Angiographic Embolization

    Raja Ahmad

    2008-10-01

    Full Text Available Juvenile nasopharyngeal angiofibroma (JNA is a rare benign neoplasm that occurs almost exclusively in the nasopharynx of adolescent males. Surgery remains the primary treatment of choice. JNA has always presented a management challenge to surgeons because of its vascular nature, site of occurrence, and local tissue destruction. The surgical approaches are either standard open method which include external or intraoral incisions, or the recent advanced approach, i.e. via using the endonasal endoscope. It is widely accepted that the use of preoperative angiographic embolization reduces the occurrence of intraoperative bleeding and facilitates tumour removal. However, angiographic embolization is not available at all centres. The purpose of this article is to present our experience with five patients diagnosed with JNA who were resected without embolization, using various surgical approaches. Two tumours were removed via endonasal endoscopic surgery. None of the tumours were embolized prior to surgery. We highlight the preoperative evaluation of tumour extent, using both computed tomography (CT and magnetic resonance angiography, and the importance of temporary clamping of the external carotid artery intraoperatively. Our results suggest that the latter procedure is a safe and effective means of facilitating surgery and reducing intraoperative bleeding.

  6. Angiographic features of 26 children with Takayasu's arteritis

    McCulloch, M.; Goddard, E.; Sinclair, P.; Andronikou, S.; Mandelstam, S.; Beningfield, S.J.; Lawrenson, J.; Millar, A.J.W.

    2003-01-01

    Background: Takayasu's arteritis (TA) is a chronic idiopathic inflammatory disease affecting primarily the aorta, its proximal branches and the pulmonary arteries Objectives: To retrospectively review the angiograms of children with TA so as to describe the patterns of vascular involvement. Patients and methods: Twenty-six children with TA who differed from most other studies in that almost all of them presented with hypertension, reflecting the incidence of abdominal aortic and renal artery involvement. Results: The most consistent finding was stenosis of the aorta. Marginal irregularity/undulation of the aorta was also a useful angiographic diagnostic feature in subtle disease. The incidence of aneurysms was high compared to other studies and both fusiform and saccular aneurysms were encountered. Percutaneous transluminal angioplasty (PTA) was successful in all eight patients in whom it was performed. MRI, CT angiography and US are discussed as less invasive imaging alternatives. TA is a significant cause of renovascular hypertension in children in South Africa where there is a high incidence of tuberculous infection. Knowledge of the angiographic features and pattern of aortic involvement is essential for diagnosis and initiation of early and appropriate treatment, including PTA. (orig.)

  7. Transvenous embolization of cavernous sinus dural arteriovenous fistula via angiographic occlusive inferior petrous sinus

    Chao-Bao Luo

    2015-09-01

    Conclusion: Angiographic occlusive IPS of CSDAVF may be related to true occlusion of IPS or patent IPS with compartment of the IPS-CS. There is no statistically significant difference in procedural times for these two different fistula anatomies. Transvenous embolization via angiographic occlusive IPS is a safe and effective method to manage CSDAVFs.

  8. A comparison of chemoembolization endpoints using angiographic versus transcatheter intraarterial perfusion/MR imaging monitoring.

    Lewandowski, Robert J; Wang, Dingxin; Gehl, James; Atassi, Bassel; Ryu, Robert K; Sato, Kent; Nemcek, Albert A; Miller, Frank H; Mulcahy, Mary F; Kulik, Laura; Larson, Andrew C; Salem, Riad; Omary, Reed A

    2007-10-01

    Transcatheter arterial chemoembolization (TACE) is an established treatment for unresectable liver cancer. This study was conducted to test the hypothesis that angiographic endpoints during TACE are measurable and reproducible by comparing subjective angiographic versus objective magnetic resonance (MR) endpoints of TACE. The study included 12 consecutive patients who presented for TACE for surgically unresectable HCC or progressive hepatic metastases despite chemotherapy. All procedures were performed with a dedicated imaging system. Angiographic series before and after TACE were reviewed independently by three board-certified interventional radiologists. A subjective angiographic chemoembolization endpoint (SACE) classification scheme, modified from an established angiographic grading system in the cardiology literature, was designed to assist in reproducibly classifying angiographic endpoints. Reproducibility in SACE classification level was compared among operators, and MR imaging perfusion reduction was compared with SACE levels for each observer. Twelve patients successfully underwent 15 separate TACE sessions. SACE levels ranged from I through IV. There was moderate agreement in SACE classification (kappa = 0.46 +/- 0.12). There was no correlation between SACE level and MR perfusion reduction (r = 0.16 for one operator and 0.02 for the other two). Angiographic endpoints during TACE vary widely, have moderate reproducibility among operators, and do not correlate with functional MR imaging perfusion endpoints. Future research should aim to determine ideal angiographic and functional MR imaging endpoints for TACE according to outcome measures such as imaging response, pathologic response, and survival.

  9. Analysis of the learning curve for peroral endoscopic myotomy for esophageal achalasia: Single-center, two-operator experience.

    Lv, Houning; Zhao, Ningning; Zheng, Zhongqing; Wang, Tao; Yang, Fang; Jiang, Xihui; Lin, Lin; Sun, Chao; Wang, Bangmao

    2017-05-01

    Peroral endoscopic myotomy (POEM) has emerged as an advanced technique for the treatment of achalasia, and defining the learning curve is mandatory. From August 2011 to June 2014, two operators in our institution (A&B) carried out POEM on 35 and 33 consecutive patients, respectively. Moving average and cumulative sum (CUSUM) methods were used to analyze the POEM learning curve for corrected operative time (cOT), referring to duration of per centimeter myotomy. Additionally, perioperative outcomes were compared among distinct learning curve phases. Using the moving average method, cOT reached a plateau at the 29th case and at the 24th case for operators A and B, respectively. CUSUM analysis identified three phases: initial learning period (Phase 1), efficiency period (Phase 2) and mastery period (Phase 3). The relatively smooth state in the CUSUM graph occurred at the 26th case and at the 24th case for operators A and B, respectively. Mean cOT of distinct phases for operator A were 8.32, 5.20 and 3.97 min, whereas they were 5.99, 3.06 and 3.75 min for operator B, respectively. Eckardt score and lower esophageal sphincter pressure significantly decreased during the 1-year follow-up period. Data were comparable regarding patient characteristics and perioperative outcomes. This single-center study demonstrated that expert endoscopists with experience in esophageal endoscopic submucosal dissection reached a plateau in learning of POEM after approximately 25 cases. © 2016 Japan Gastroenterological Endoscopy Society.

  10. High resolution melting curve analysis as a new tool for rapid identification of canine parvovirus type 2 strains.

    Bingga, Gali; Liu, Zhicheng; Zhang, Jianfeng; Zhu, Yujun; Lin, Lifeng; Ding, Shuangyang; Guo, Pengju

    2014-01-01

    A high resolution melting (HRM) curve method was developed to identify canine parvovirus type 2 (CPV-2) strains by nested PCR. Two sets of primers, CPV-426F/426R and CPV-87R/87F, were designed that amplified a 52 bp and 53 bp product from the viral VP2 capsid gene. The region amplified by CPV-426F/426R included the A4062G and T4064A mutations in CPV-2a, CPV-2b and CPV-2c. The region amplified by CPV-87F/87R included the A3045T mutation in the vaccine strains of CPV-2 and CPV-2a, CPV-2b and CPV-2c. Faecal samples were obtained from 30 dogs that were CPV antigen-positive. The DNA was isolated from the faecal samples and PCR-amplified using the two sets of primers, and genotyped by HRM curve analysis. The PCR-HRM assay was able to distinguish single nucleotide polymorphisms between CPV-2a, CPV-2b and CPV-2c using CPV-426F/426R. CPV-2a was distinguished from CPV-2b and CPV-2c by differences in the melting temperature. CPV-2b and CPV-2c could be distinguished based on the shape of the melting curve after generating heteroduplexes using a CPV-2b reference sample. The vaccine strains of CPV-2 were identified using CPV-87F/87R. Conventional methods for genotyping CPV strains are labor intensive, expensive or time consuming; the present PCR-based HRM assay might be an attractive alternative. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Not proper ROC curves as new tool for the analysis of differentially expressed genes in microarray experiments

    Pistoia Vito

    2008-10-01

    Full Text Available Abstract Background Most microarray experiments are carried out with the purpose of identifying genes whose expression varies in relation with specific conditions or in response to environmental stimuli. In such studies, genes showing similar mean expression values between two or more groups are considered as not differentially expressed, even if hidden subclasses with different expression values may exist. In this paper we propose a new method for identifying differentially expressed genes, based on the area between the ROC curve and the rising diagonal (ABCR. ABCR represents a more general approach than the standard area under the ROC curve (AUC, because it can identify both proper (i.e., concave and not proper ROC curves (NPRC. In particular, NPRC may correspond to those genes that tend to escape standard selection methods. Results We assessed the performance of our method using data from a publicly available database of 4026 genes, including 14 normal B cell samples (NBC and 20 heterogeneous lymphomas (namely: 9 follicular lymphomas and 11 chronic lymphocytic leukemias. Moreover, NBC also included two sub-classes, i.e., 6 heavily stimulated and 8 slightly or not stimulated samples. We identified 1607 differentially expressed genes with an estimated False Discovery Rate of 15%. Among them, 16 corresponded to NPRC and all escaped standard selection procedures based on AUC and t statistics. Moreover, a simple inspection to the shape of such plots allowed to identify the two subclasses in either one class in 13 cases (81%. Conclusion NPRC represent a new useful tool for the analysis of microarray data.

  12. Recent trends in application of multivariate curve resolution approaches for improving gas chromatography-mass spectrometry analysis of essential oils.

    Jalali-Heravi, Mehdi; Parastar, Hadi

    2011-08-15

    Essential oils (EOs) are valuable natural products that are popular nowadays in the world due to their effects on the health conditions of human beings and their role in preventing and curing diseases. In addition, EOs have a broad range of applications in foods, perfumes, cosmetics and human nutrition. Among different techniques for analysis of EOs, gas chromatography-mass spectrometry (GC-MS) is the most important one in recent years. However, there are some fundamental problems in GC-MS analysis including baseline drift, spectral background, noise, low S/N (signal to noise) ratio, changes in the peak shapes and co-elution. Multivariate curve resolution (MCR) approaches cope with ongoing challenges and are able to handle these problems. This review focuses on the application of MCR techniques for improving GC-MS analysis of EOs published between January 2000 and December 2010. In the first part, the importance of EOs in human life and their relevance in analytical chemistry is discussed. In the second part, an insight into some basics needed to understand prospects and limitations of the MCR techniques are given. In the third part, the significance of the combination of the MCR approaches with GC-MS analysis of EOs is highlighted. Furthermore, the commonly used algorithms for preprocessing, chemical rank determination, local rank analysis and multivariate resolution in the field of EOs analysis are reviewed. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. A finite element model for the stress and flexibility analysis of curved pipes

    Guerreiro, J.N.C.

    1987-03-01

    We present a finite element model for the analysis of pipe bends with flanged ends or flanged tangents. Comments are made on the consideration of the internal pressure load. Flexibility and stress instensification factores obtained with the present model are compared with others available. (Author) [pt

  14. Principal response curves: analysis of time-dependent multivariate responses of biological community to stress

    Brink, van den P.J.; Braak, ter C.J.F.

    1999-01-01

    In this paper a novel multivariate method is proposed for the analysis of community response data from designed experiments repeatedly sampled in time. The long-term effects of the insecticide chlorpyrifos on the invertebrate community and the dissolved oxygen (DO)–pH–alkalinity–conductivity

  15. A simplified early-warning system for imminent landslide prediction based on failure index fragility curves developed through numerical analysis

    Ugur Ozturk

    2016-07-01

    Full Text Available Early-warning systems (EWSs are crucial to reduce the risk of landslide, especially where the structural measures are not fully capable of preventing the devastating impact of such an event. Furthermore, designing and successfully implementing a complete landslide EWS is a highly complex task. The main technical challenges are linked to the definition of heterogeneous material properties (geotechnical and geomechanical parameters as well as a variety of the triggering factors. In addition, real-time data processing creates a significant complexity, since data collection and numerical models for risk assessment are time consuming tasks. Therefore, uncertainties in the physical properties of a landslide together with the data management represent the two crucial deficiencies in an efficient landslide EWS. Within this study the application is explored of the concept of fragility curves to landslides; fragility curves are widely used to simulate systems response to natural hazards, i.e. floods or earthquakes. The application of fragility curves to landslide risk assessment is believed to simplify emergency risk assessment; even though it cannot substitute detailed analysis during peace-time. A simplified risk assessment technique can remove some of the unclear features and decrease data processing time. The method is based on synthetic samples which are used to define the approximate failure thresholds for landslides, taking into account the materials and the piezometric levels. The results are presented in charts. The method presented in this paper, which is called failure index fragility curve (FIFC, allows assessment of the actual real-time risk in a case study that is based on the most appropriate FIFC. The application of an FIFC to a real case is presented as an example. This method to assess the landslide risk is another step towards a more integrated dynamic approach to a potential landslide prevention system. Even if it does not define

  16. Growth curve analysis for plasma profiles using smoothing splines. Final report, January 1993--January 1995

    Imre, K.

    1995-07-01

    In this project, we parameterize the shape and magnitude of the temperature and density profiles on JET and the temperature profiles on TFTR. The key control variables for the profiles were tabulated and the response functions were estimated. A sophisticated statistical analysis code was developed to fit the plasma profiles. Our analysis indicate that the JET density shape depends primarily on bar n/B t for Ohmic heating, bar n for L-mode and I p for H-mode. The temperature profiles for JET are mainly determined by q 95 for the case of Ohmic heating, and by B t and P/bar n for the L-mode. For the H-mode the shape depends on the type of auxiliary heating, Z eff , N bar n, q 95 , and P

  17. Exploring the existence of Kuznets curve in countries' environmental efficiency using DEA window analysis

    Halkos, George Emm.; Tzeremes, Nickolaos G.

    2009-01-01

    This paper, using data envelopment (DEA) window analysis and generalized method of moments (GMM) estimators, examines the existence of a Kuznets type relationship between countries' environmental efficiency and national income. Specifically, it measures the environmental efficiency of 17 OECD countries by constructing environmental efficiency ratios for the time period 1980-2002. The analysis with the application of dynamic panel data reveals that there isn't a Kuznets type relationship between environmental efficiency and income. Allowing for dynamic effects we find that the adjustment to the target ratio is instantaneous. We also find that increased economic activity does not always ensure environmental protection and thus the path of growth is important in addition to the growth itself. (author)

  18. Exploring the existence of Kuznets curve in countries' environmental efficiency using DEA window analysis

    Halkos, George Emm.; Tzeremes, Nickolaos G. [Department of Economics, University of Thessaly, Korai 43, 38333, Volos (Greece)

    2009-05-15

    This paper, using data envelopment (DEA) window analysis and generalized method of moments (GMM) estimators, examines the existence of a Kuznets type relationship between countries' environmental efficiency and national income. Specifically, it measures the environmental efficiency of 17 OECD countries by constructing environmental efficiency ratios for the time period 1980-2002. The analysis with the application of dynamic panel data reveals that there isn't a Kuznets type relationship between environmental efficiency and income. Allowing for dynamic effects we find that the adjustment to the target ratio is instantaneous. We also find that increased economic activity does not always ensure environmental protection and thus the path of growth is important in addition to the growth itself. (author)

  19. Right ventricular ejection fraction - comparison of various angiographic and radionuclide approaches

    Schicha, H.; Tebbe, U.; Voth, E.; Sciagra, R.; Schultz, W.; Neuhaus, G.; Goettingen Univ.

    1987-01-01

    In 21 patients with various heart diseases RVEF was measured angiographically and by radionuclide ventriculography. Using biplane angiocardiography evaluation was performed by 7 different methods (Simpson's rule, Dogde, Arcilla, Ferlinz, Duebel). Using equilibrium RNV, evaluation was performed by 9 modifications of analysis. Problems were evident to separate the right atrium from the ventricle and to define the site of the pulmonary valve. The results show that when using the various methods of angiography considerable variations of the absolute volumes occur, but least so with RVEF. When using RNV with one single enddiastolic ROI, the RVEF was much too low. By means of the enddiastolic/endsystolic Double-ROI-method a good agreement with angiography was found, with correlation coefficients up to r=0.85. There was only a minor effect of background correction. (orig.) [de

  20. Learning Curve? Which One?

    Paulo Prochno

    2004-07-01

    Full Text Available Learning curves have been studied for a long time. These studies provided strong support to the hypothesis that, as organizations produce more of a product, unit costs of production decrease at a decreasing rate (see Argote, 1999 for a comprehensive review of learning curve studies. But the organizational mechanisms that lead to these results are still underexplored. We know some drivers of learning curves (ADLER; CLARK, 1991; LAPRE et al., 2000, but we still lack a more detailed view of the organizational processes behind those curves. Through an ethnographic study, I bring a comprehensive account of the first year of operations of a new automotive plant, describing what was taking place on in the assembly area during the most relevant shifts of the learning curve. The emphasis is then on how learning occurs in that setting. My analysis suggests that the overall learning curve is in fact the result of an integration process that puts together several individual ongoing learning curves in different areas throughout the organization. In the end, I propose a model to understand the evolution of these learning processes and their supporting organizational mechanisms.

  1. Detection of icing on wind turbine blades by means of vibration and power curve analysis

    Skrimpas, Georgios Alexandros; Kleani, Karolina; Mijatovic, Nenad

    2016-01-01

    accelerometers and power performance analysis. Features extracted from these two techniques serve as inputs in a decision-making scheme, allowing early activation of de-icing systems or shut down of the wind turbine. An additional parameter is the month of operation, assuring consistent outcomes in both winter......Ice accretion on wind turbines' blades is one of the main challenges of systems installed in cold climate locations, resulting in power performance deterioration and excessive nacelle oscillation. In this work, consistent detection of icing events is achieved utilizing indications from the nacelle...

  2. STRESS - STRAIN CURVE ANALYSIS OF WOVEN FABRICS MAD E FROM COMBED YARNS TYPE WOOL

    VÎLCU Adrian; HRISTIAN Liliana; BORDEIANU Demetra L.; VÎLCU Catalin

    2014-01-01

    The paper analyses the tensile behavior of woven fabrics made from 45%Wool + 55% PES used for garments. Analysis of fabric behavior during wearing has shown that these are submitted to simple and repeated uni-axial or bi-axial tensile strains. The level of these strains is often within the elastic limit, rarely going over yielding. Therefore the designer must be able to evaluate the mechanical behavior of such fabrics in order to control the fabric behavior in the garment. This evaluation is ...

  3. Blast response of curved carbon/epoxy composite panels: Experimental study and finite-element analysis

    Phadnis, V A; Roy, A; Silberschmidt, V V; Kumar, P; Shukla, A

    2013-01-01

    Experimental and numerical studies were conducted to understand the effect of plate curvature on blast response of carbon/epoxy composite panels. A shock-tube system was utilized to impart controlled shock loading to quasi-isotropic composite panels with differing range of radii of curvatures. A 3D Digital Image Correlation (DIC) technique coupled with high-speed photography was used to obtain out-of-plane deflection and velocity, as well as in-plane strain on the back face of the panels. Macroscopic post-mortem analysis was performed to compare yielding and deformation in these panels. A dynamic computational simulation that integrates fluid-structure interaction was conducted to evaluate the panel response in general purpose finite-element software ABAQUS/Explicit. The obtained numerical results were compared to the experimental data and showed a good correlation

  4. Analysis and Extension of the PCA Method, Estimating a Noise Curve from a Single Image

    Miguel Colom

    2016-12-01

    Full Text Available In the article 'Image Noise Level Estimation by Principal Component Analysis', S. Pyatykh, J. Hesser, and L. Zheng propose a new method to estimate the variance of the noise in an image from the eigenvalues of the covariance matrix of the overlapping blocks of the noisy image. Instead of using all the patches of the noisy image, the authors propose an iterative strategy to adaptively choose the optimal set containing the patches with lowest variance. Although the method measures uniform Gaussian noise, it can be easily adapted to deal with signal-dependent noise, which is realistic with the Poisson noise model obtained by a CMOS or CCD device in a digital camera.

  5. Curve thermoluminescent analysis of ZrO2 doped with nanoparticles and Ag nano fibers

    Mendoza A, D.; Villa S, G.; Gutierrez W, C.; Perez H, R.; Gonzalez M, P.

    2008-01-01

    This paper presents the results obtained from the analysis of the high temperature thermoluminescence response induced by UV radiation in pure zirconium (ZrO 2 ) and doped with Ag nanoparticles and Ag nano fibers. The zirconium samples were obtained by the sol-gel method and irradiated with a UV lamp for different times. The results showed that the presence of the dopants change the characteristics of the traps associated with the high temperature peak which is located at 230 C for pure zirconium, and that the greater influence is due the presence of Ag nano fibers, inducing a shift to lower temperatures. It also presents the thermoluminescence response as a function of irradiation time. (Author)

  6. Radial artery pulse waveform analysis based on curve fitting using discrete Fourier series.

    Jiang, Zhixing; Zhang, David; Lu, Guangming

    2018-04-19

    Radial artery pulse diagnosis has been playing an important role in traditional Chinese medicine (TCM). For its non-invasion and convenience, the pulse diagnosis has great significance in diseases analysis of modern medicine. The practitioners sense the pulse waveforms in patients' wrist to make diagnoses based on their non-objective personal experience. With the researches of pulse acquisition platforms and computerized analysis methods, the objective study on pulse diagnosis can help the TCM to keep up with the development of modern medicine. In this paper, we propose a new method to extract feature from pulse waveform based on discrete Fourier series (DFS). It regards the waveform as one kind of signal that consists of a series of sub-components represented by sine and cosine (SC) signals with different frequencies and amplitudes. After the pulse signals are collected and preprocessed, we fit the average waveform for each sample using discrete Fourier series by least squares. The feature vector is comprised by the coefficients of discrete Fourier series function. Compared with the fitting method using Gaussian mixture function, the fitting errors of proposed method are smaller, which indicate that our method can represent the original signal better. The classification performance of proposed feature is superior to the other features extracted from waveform, liking auto-regression model and Gaussian mixture model. The coefficients of optimized DFS function, who is used to fit the arterial pressure waveforms, can obtain better performance in modeling the waveforms and holds more potential information for distinguishing different psychological states. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. High-resolution melt-curve analysis of random-amplified-polymorphic-DNA markers, for the characterisation of pathogenic Leptospira

    Tulsiani, Suhella; Craig, S B; Graham, G C

    2010-01-01

    A new test for pathogenic Leptospira isolates, based on RAPD-PCR and high-resolution melt (HRM) analysis (which measures the melting temperature of amplicons in real time, using a fluorescent DNA-binding dye), has recently been developed. A characteristic profile of the amplicons can be used...... typed against 13 previously published RAPD primers, using a real-time cycler (the Corbett Life Science RotorGene 6000) and the optimised reagents from a commercial kit (Quantace SensiMix). RAPD-HRM at specific temperatures generated defining amplicon melt profiles for each of the tested serovars....... These profiles were evaluated as difference-curve graphs generated using the RotorGene software package, with a cut-off of at least 8 'U' (plus or minus). The results demonstrated that RAPD-HRM can be used to measure serovar diversity and establish identity, with a high degree of stability. The characterisation...

  8. Automatic and objective oral cancer diagnosis by Raman spectroscopic detection of keratin with multivariate curve resolution analysis

    Chen, Po-Hsiung; Shimada, Rintaro; Yabumoto, Sohshi; Okajima, Hajime; Ando, Masahiro; Chang, Chiou-Tzu; Lee, Li-Tzu; Wong, Yong-Kie; Chiou, Arthur; Hamaguchi, Hiro-O.

    2016-01-01

    We have developed an automatic and objective method for detecting human oral squamous cell carcinoma (OSCC) tissues with Raman microspectroscopy. We measure 196 independent Raman spectra from 196 different points of one oral tissue sample and globally analyze these spectra using a Multivariate Curve Resolution (MCR) analysis. Discrimination of OSCC tissues is automatically and objectively made by spectral matching comparison of the MCR decomposed Raman spectra and the standard Raman spectrum of keratin, a well-established molecular marker of OSCC. We use a total of 24 tissue samples, 10 OSCC and 10 normal tissues from the same 10 patients, 3 OSCC and 1 normal tissues from different patients. Following the newly developed protocol presented here, we have been able to detect OSCC tissues with 77 to 92% sensitivity (depending on how to define positivity) and 100% specificity. The present approach lends itself to a reliable clinical diagnosis of OSCC substantiated by the “molecular fingerprint” of keratin.

  9. Analysis of the width-w non-adjacent form in conjunction with hyperelliptic curve cryptography and with lattices☆

    Krenn, Daniel

    2013-01-01

    In this work the number of occurrences of a fixed non-zero digit in the width-w non-adjacent forms of all elements of a lattice in some region (e.g. a ball) is analysed. As bases, expanding endomorphisms with eigenvalues of the same absolute value are allowed. Applications of the main result are on numeral systems with an algebraic integer as base. Those come from efficient scalar multiplication methods (Frobenius-and-add methods) in hyperelliptic curves cryptography, and the result is needed for analysing the running time of such algorithms. The counting result itself is an asymptotic formula, where its main term coincides with the full block length analysis. In its second order term a periodic fluctuation is exhibited. The proof follows Delange’s method. PMID:23805020

  10. The Environmental Kuznets Curve for Water Quality: An Analysis of its Appropriateness Using Unit Root and Cointegration Tests

    Juan Carlos Muñoz

    2008-12-01

    Full Text Available The Environmental Kuznets Curve hypothesis suggests the existence of an inverted U-shaped relationship between environmental degradation and income. Several economists assume that the environmental impacts occurred during the first stages of the development process will be reverted as a result of economic growth. Yet Perman and Stern (2003 have argued that the econometric methods used in the earlier analysis of the EKC are inappropriate, given the time properties of the series. This article examines the appropriateness of the EKC for a panel of 46 countries and 21 periods by implementing individual and panel tests for unit roots and cointegration. An error correction model is also estimated. The results do not support evidence of a common EKC for the countries analyzed.

  11. Learning from uncertain curves

    Mallasto, Anton; Feragen, Aasa

    2017-01-01

    We introduce a novel framework for statistical analysis of populations of nondegenerate Gaussian processes (GPs), which are natural representations of uncertain curves. This allows inherent variation or uncertainty in function-valued data to be properly incorporated in the population analysis. Us...

  12. Model-based, semiquantitative and time intensity curve shape analysis of dynamic contrast-enhanced MRI: a comparison in patients undergoing antiangiogenic treatment for recurrent glioma

    Lavini, Cristina; Verhoeff, Joost J. C.; Majoie, Charles B.; Stalpers, Lukas J. A.; Richel, Dick J.; Maas, Mario

    2011-01-01

    To compare time intensity curve (TIC)-shape analysis of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) data with model-based analysis and semiquantitative analysis in patients with high-grade glioma treated with the antiangiogenic drug bevacizumab. Fifteen patients had a pretreatment

  13. Radionuclide detection and differential diagnosis of left-to-right cardiac shunts by analysis of time-activity curves

    Kim, Ok-Hwa

    1986-01-01

    The noninvasive nature of the radionuclide angiocardiography provided a useful approach for the evaluation of left-to-right cardiac shunts (LRCS). While the qualitative information can be obtained by inspection of serial radionuclide angiocardiograms, the quantitative information of radionuclide angiocardiography can be obtained by the analysis of time-activity curves using advanced computer system. The count ratios method and pulmonary-to-systemic flow ratio (QP/QS) by gamma variate fit method were used to evaluate the accuracy of detection and localization of LRCS. One hundred and ten time-activity curves were analyzed. There were 46 LRCS (atrial septal defects 11, ventricular septal defects 22, patent ductus arteriosus 13) and 64 normal subjects. By computer analysis of time-activity histograms of the right atrium, ventricle and the lungs separately, the count ratios modified by adding the mean cardiac transit time were calculated in each anatomic site. In normal subjects the mean count ratios in the right atrium, ventricle and lungs were 0.24 on average. In atrial septal defects, the count ratios were high in the right atrium, ventricle and lungs, whereas in ventricular septal defects the count ratios were higher only in the right ventricle and lungs. Patent ductus arteriosus showed normal count ratios in the heart but high count ratios were obtained in the lungs. Thus, this count ratios method could be separated normal from those with intracardiac or extracardiac shunts, and moreover, with this method the localization of the shunts level was possible in LRCS. Another method that could differentiate the intracardiac shunts from extracardiac shunts was measuring QP/QS in the left and right lungs. In patent ductus arteriosus, the left lung QP/QS was hight than those of the right lung, whereas in atrial septal defects and ventricular septal defects QP/QS ratios were equal in both lungs. (J.P.N.)

  14. Rayleigh-Taylor instability under curved substrates: An optimal transient growth analysis

    Balestra, Gioele; Brun, P.-T.; Gallaire, François

    2016-12-01

    We investigate the stability of thin viscous films coated on the inside of a horizontal cylindrical substrate. In such a case, gravity acts both as a stabilizing force through the progressive drainage of the film and as a destabilizing force prone to form droplets via the Rayleigh-Taylor instability. The drainage solution, derived from lubrication equations, is found asymptotically stable with respect to infinitesimally small perturbations, although in reality, droplets often form. To resolve this paradox, we perform an optimal transient growth analysis for the first-order perturbations of the liquid's interface, generalizing the results of Trinh et al. [Phys. Fluids 26, 051704 (2014), 10.1063/1.4876476]. We find that the system displays a linear transient growth potential that gives rise to two different scenarios depending on the value of the Bond number (prescribing the relative importance of gravity and surface tension forces). At low Bond numbers, the optimal perturbation of the interface does not generate droplets. In contrast, for higher Bond numbers, perturbations on the upper hemicircle yield gains large enough to potentially form droplets. The gain increases exponentially with the Bond number. In particular, depending on the amplitude of the initial perturbation, we find a critical Bond number above which the short-time linear growth is sufficient to trigger the nonlinear effects required to form dripping droplets. We conclude that the transition to droplets detaching from the substrate is noise and perturbation dependent.

  15. Identification of Dynamic Flow Stress Curves Using the Virtual Fields Methods: Theoretical Feasibility Analysis

    Leem, Dohyun; Kim, Jin-Hwan; Barlat, Frédéric; Song, Jung Han; Lee, Myoung-Gyu

    2018-03-01

    An inverse approach based on the virtual fields method (VFM) is presented to identify the material hardening parameters under dynamic deformation. This dynamic-VFM (D-VFM) method does not require load information for the parameter identification. Instead, it utilizes acceleration fields in a specimen's gage region. To investigate the feasibility of the proposed inverse approach for dynamic deformation, the virtual experiments using dynamic finite element simulations were conducted. The simulation could provide all the necessary data for the identification such as displacement, strain, and acceleration fields. The accuracy of the identification results was evaluated by changing several parameters such as specimen geometry, velocity, and traction boundary conditions. The analysis clearly shows that the D-VFM which utilizes acceleration fields can be a good alternative to the conventional identification procedure that uses load information. Also, it was found that proper deformation conditions are required for generating sufficient acceleration fields during dynamic deformation to enhance the identification accuracy with the D-VFM.

  16. Biological dosimetry in radiation accidents. Dose-response curve by chromosomal aberrations analysis

    Hadjidekova, V.; Hristova, R.; Atanasova, P.; Popova, L.; Stainova, A.; Bulanova, M.; Georgieva, I.; Vukov, M.

    2005-01-01

    The aim of this paper is to obtain a dose-response relationship for chromosomal aberrations induced in human lymphocytes after in vitro irradiation. Peripheral blood samples of 7 different donors were used. The blood irradiation was done with Cs137 gamma-rays at different doses: 0.0, 0.05, 0.1, 0.25, 0.5, 0.75, 1.0, 1.5, 2.0 and 3.0 Gy. Lymphocyte cultures were established and maintain for 48 hours at 37 0 C in CO 2 incubator for chromosomal aberration analysis. The dose response relationship has been established based on dysenteric and ring chromosomes yield. The relationship can be described by the following equation: Y = 0.0274D + 0.0251 D 2 , where (Y) = dysenteric and ring chromosomes yield, (D) = radiation dose obtained. EXCEL software was established for calculation of the received dose by using this equation, as a whole body equivalent dose acute irradiation

  17. A COMPREHENSIVE ANALYSIS OF SWIFT/X-RAY TELESCOPE DATA. IV. SINGLE POWER-LAW DECAYING LIGHT CURVES VERSUS CANONICAL LIGHT CURVES AND IMPLICATIONS FOR A UNIFIED ORIGIN OF X-RAYS

    Liang Enwei; Lue Houjun; Hou Shujin; Zhang Binbin; Zhang Bing

    2009-01-01

    parent sample. Referenced to T 0 , the canonical XRT light curves well trace the SPL light curves. The T 0 's of the canonical light curves in our analysis are usually much larger than the offsets of the known precursors from the main GRBs. If the prior emission hypothesis is real, the X-ray emission is better interpreted within the external shock models based on the spectral and temporal indices of the X-rays. The lack of detection of a jet-like break in most XRT light curves implies that the opening angle of the prior emission jet would be usually large.

  18. Computer tomographic and angiographic studies of histologically confirmed intrahepatic masses

    Janson, R.; Lackner, K.; Paquet, K.J.; Thelen, M.; Thurn, P.

    1980-01-01

    The computer tomographic and angiographic findings in 53 patients with intrahepatic masses were compared. The histological findings show that 17 were due to echinococcus, 12 were due to hepatic carcinoma, ten were metastases, five patients had focal nodular hyperplasia, three an alveolar echinococcus and there were three cases with an haemangioma of the liver and a further three liver abscesses. Computer tomography proved superior in peripherally situated lesions, and in those in the left lobe of the liver. Arteriography was better at demonstrating lesions below 2 cm in size, particularly vascular tumours. As a pre-operative measure, angiography is to be preferred since it is able to demonstrate anatomic anomalies and variations in the blood supply, as well as invasion of the portal vein or of the inferior vena cava. (orig.) [de

  19. Computer tomographic and angiographic studies of histologically confirmed intrahepatic masses

    Janson, R.; Lackner, K.; Paquet, K.J.; Thelen, M.; Thurn, P.

    1980-06-01

    The computer tomographic and angiographic findings in 53 patients with intrahepatic masses were compared. The histological findings show that 17 were due to echinococcus, 12 were due to hepatic carcinoma, ten were metastases, five patients had focal nodular hyperplasia, three an alveolar echinococcus and there were three cases with an haemangioma of the liver and a further three liver abscesses. Computer tomography proved superior in peripherally situated lesions, and in those in the left lobe of the liver. Arteriography was better at demonstrating lesions below 2 cm in size, particularly vascular tumours. As a pre-operative measure, angiography is to be preferred since it is able to demonstrate anatomic anomalies and variations in the blood supply, as well as invasion of the portal vein or of the inferior vena cava.

  20. Angiographic examinations with the medium size technique (70 mm films)

    Heuck, F.; Reichardt, W.

    1981-01-01

    The applicability of medium-size technique was tested in angiographic examinations of thoracic and abdominal organs. By means of full-size image intensifiers it is possible to carry out organ angiography, and by means of a pace control mechanism for the patient transport, the angiography of the extremities can be realized. Examples are given illustrate the informational value in cases where the arial and venous vascular systems of organs and extremities are concerned. The particular advantages for functional analyses of organ circulatory systems in cases of angiography are described. Two factors of importance are pointed out: the reduction of the exposure to irradiation for the patient on the one hand, and the increasing film prices on the other hand. The authors demand to overcome the psychological problems arising in the medical working groups where the medium-size technique shall be introduced into routine diagnostics. (orig./APR) [de

  1. A characteristic of angiographic cone-beam CT

    Takase, Tadashi; Take, Toshio; Nakazawa, Yasuo; Kinouchi, Katsunori

    2009-01-01

    Angiographic cone-beam CT, called DynaCT by SIEMENS, is a 3D imaging tool reconstructed from projection data by a rotational C-arm with a flat panel detector. It can visualize low-contrast objects such as soft tissue or small vessels as well as high-contrast structures such as enhanced vessels or bone. We need to understand its image characteristics and dose distribution during 200 degree rotation around a patient. In this research, we evaluated fundamental characteristics and dose effectiveness for optimized clinical images. DynaCT, including soft tissue information and isochronal voxel data along the z-axis, could provide enough CT-like image quality for interventional radiology (IVR) use. In addition, evaluation of accumulated dose distribution helped us to predict and avoid the occurrence of radiodermatitis. Thus, DynaCT is useful as a support and navigation tool for IVR. (author)

  2. Angiographic prevalence and pattern of coronary artery disease in women.

    Ezhumalai, Babu; Jayaraman, Balachander

    2014-01-01

    There are not many studies describing the prevalence and pattern of "coronary artery disease" (CAD) in women undergoing "coronary angiography" (CAG). Hence, uncertainty thrives with regard to the angiographic prevalence and pattern of CAD in women. Our objective was to study the prevalence and pattern of CAD among women undergoing CAG. Data of 500 women who underwent CAG for suspected CAD over 3 years were retrospectively analyzed. They were classified into young group (age right coronary artery. Bifurcation lesion involving distal left main coronary artery is the most prevalent pattern of LMD. There has been a change with regard to clinical presentation and onset of risk factors for CAD at young age, but the load of atherosclerotic burden and pattern of involvement of coronary arteries have not changed in women. Copyright © 2014 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

  3. Radioembolization with 90Y Microspheres: Angiographic and Technical Considerations

    Lewandowski, Robert J.; Sato, Kent T.; Atassi, Bassel; Ryu, Robert K.; Nemcek, Albert A.; Kulik, Laura; Geschwind, Jean-Francois; Murthy, Ravi; Rilling, William; Liu, David; Bester, Lourens; Bilbao, Jose Ignacio; Kennedy, Andrew S.; Omary, Reed A.; Salem, Riad

    2007-01-01

    The anatomy of the mesenteric system and the hepatic arterial bed has been demonstrated to have a high degree of variation. This is important when considering pre-surgical planning, catheterization, and trans-arterial hepatic therapies. Although anatomical variants have been well described, the characterization and understanding of regional hepatic perfusion in the context of radioembolization have not been studied with great depth. The purpose of this review is to provide a thorough discussion and detailed presentation of the angiographic and technical aspects of radioembolization. Normal vascular anatomy, commonly encountered variants, and factors involved in changes to regional perfusion in the presence of liver tumors are discussed. Furthermore, the principles described here apply to all liver-directed transarterial therapies

  4. Clinical Investigation of Radiation Retinopathy Fundus and Fluorescein Angiographic Features

    LiMei; QiuGT

    1999-01-01

    Purpose:To investigate the fundus and fluorescein angiographic features in the patients with radiation retinopathy.Clinical Materials:Color fundus photography and/or fluorescein angiography from 13 patients with nasopharyngeal carcinomas received external beam radiation were retrospectively analyzed.Reslts:In this study,26 damaged eyes of 13 patients eveloped some degree of radiation retinopathy.The earliest and most common finding was macular microvascular changes (microaneurysms and/or telangiectasia),which was observed in 100%(26/26)of the eyes.Intraretinal hemorrhages,macular capillary nonperfusion,and macular edema were noted in 84%,50%,and 42% of the eyes,respectively.Conclusions:Radiation retinopathy is common after external beam radiation of nasopharyngeal carcinomas.The prominent changes include maular microvascular changes,intraretinal hemorrhages and macular capillary nonperfusion.

  5. Clinical-angiographic correlations in 132 patients with megadolichovertebrobasilar anomaly

    Resta, M; Gentile, M A; Di Cuonzo, F; Vinjau, E; Brindicci, D; Carella, A

    1984-05-01

    We have found numerous case reports, but no systematic study of the megadolichovertebrobasilar anomaly (MDVBA). The purpose of this paper is to evaluate the relationships between arterial shifts of the vertebro-basilar system and neurological findings in the posterios fossa in our series of 132 cases. We found a high percentage (77.3%) of angiographic-clinical correlations having evaluated the arterial shifts, measured in mm, of the vertebro basilar system in a frontal and a sagittal plane and concluded that the greater the degree of dislocation, the greater the number of Istituto di Radiologia Universita degli studi of Bari, positive cases. Nevertheless it is not possible to predetermine the presence of particular neurosymptomathology related to arterial dislocation degrees.

  6. Angiographic evaluation of response to preoperative chemotherapy in osteosarcoma

    Carrasco, C.H.; Charnsangavej, C.; Richii, W.; Wallace, S.; Chawla, S.P.; Raymond, A.K.; Murray, J.A.; Benjamin, R.S.

    1986-01-01

    Preoperative chemotherapy for osteosarcoma facilitates local resection for limb salvage and serves as an in vivo chemosensitivity assay. Arteriograms obtained with each intraarterial course of cisplatin in 79 patients with osteosarcoma were evaluated. Complete remission was defined as complete or nearly complete disappearance of tumor vascularity after treatment. A minimal decrease, no change, or an increase in tumor vascularity was not considered a response. If a complete remission is assumed to represent ≥ 90% histologic tumor necrosis which correlates with prolonged disease-free survival, the sensitivity of an angiographic complete remission was 95%, the specificity was 58%, the predictive value of a negative study was 90%, and the predictive value of a positive study was 75%. Angiography is the best clinical technique for evaluating the therapeutic response in osteosarcoma. Results correlate well with the degree of tumor necrosis, particularly in respect to significant residual viable tumor

  7. Clinical presentations and MRI findings of angiographically occult vascular malformations

    Kida, Yoshihisa; Kobayashi, Tatsuya; Tanaka, Takayuki; Oyama, Hirofumi; Iwakoshi, Takayasu

    1994-01-01

    Various clinical features as well as MRI findings of AOVM (angiographically occult vascular malformation) were studied. Amongst out patients, since January 1988, there have been 30 cases of symptomatic AOVM (20 males, 10 females) including 4 cases with multiple lesions. The age ranged from 3 to 60 years of age, with a mean of 33.4 years. The locations of symptomatic lesions were in the cerebral hemisphere (15), the thalamus (4), the brain stem (8) and in the cerebellum (3). The initial presentations of these 30 cases were either by hemorrhage (18), convulsive seizure (9) or by progressive neurological deficits (3). The initial presentation was not related to the patient's age and the size of the lesion, but apparently related to the location of AOVM. Most of the lesions in the cerebral hemisphere presented seizures, but all of the lesions in the thalamus, the brain stem and the cerebellum disclosed hemorrhage as an initial presentation. In fact it was noticed that brain stem lesions tend to cause repetitive hemorrhage in a relatively short period. AOVM lesions were clearly visualized with T2-weighted MRI images, consisting of high intensity cores with surrounding low intensity rims. Most of the symptomatic lesions were partially enhanced by Gd-DTPA with varied intensity. Dynamic changes in size and enhancement pattern on MRI were occasionally seen, usually accompanied with episodes such as hemorrhage or neurological deterioration. Although AOVMs were angiographically negative some strands indicating draining veins were observed on MRI in several cases. In contrast, none of the nonsymptomatic lesions (22 lesions) demonstrated enhancement effects with Gd-DTPA. (author)

  8. CLINICAL AND ANGIOGRAPHIC PROFILE OF PATIENTS WITH COMPLETE HEART BLOCK

    Kavya Pingali

    2017-05-01

    Full Text Available BACKGROUND The angiographic findings and prognosis of patients with Complete Heart Block (CHB remain unclear. Thus, we aimed to study the clinical profile, risk factors, angiographic distribution and in-hospital outcomes of patients with complete heart block. MATERIALS AND METHODS This was a prospective, single-centred study which included 100 patients who came to the emergency department with CHB. Routine blood investigations including serum electrolytes were done. Coronary angiogram was done and lesions were assessed. Temporary pacemaker was implanted followed by permanent pacemakers in required patients, and in-hospital complications were noted down. RESULTS Commonest age group was above 60 years (75%. The patients were predominantly males. Most common presentation was chest pain (60%; there was regional wall motion abnormality in 30% patients. Degenerative complete heart block was seen in 34% patients, diphtheric myocarditis in 15%, hypokalaemic in 15%, dilated cardiomyopathy in 2%. Of total 53 patients had AV block, 14 had bifascicular block, 23 had LBBB, 6 had RBBB, 3 had Mobitz I and 1 had Mobitz II. Inferior wall myocardial infarction (MI was pervasively present in patients. Temporary pacemakers were implanted in 6 patients and permanent pacemakers in 43 patients. In-hospital outcomes constituted of complication like cardiogenic shock (10% and death (26%. The patients who died either had 80% -90% stenosis in RCA, triple vessel disease, ostioproximal LAD occlusion or diphtheric myocarditis. CONCLUSION Complete heart block was majorly associated with advanced age and inferior wall MI, virtually caused by dominant RCA occlusion. The in-hospital mortality was significantly higher in the patients with CHB.

  9. Angiographic differentiation of type of ventricular septal defects

    Cheon, Mal Soon; Park, Hee Young; Kim, Yang Sook

    1989-01-01

    Defects of the ventricular septum are the commonest type of congenital cardiac malformations. A classification with axial angiography of the subtypes of ventricular septal defects is proposed on the study of 126 patients with defects of the ventricular septum. The results were as follows: 1. The incidence of the ventricular septal defects was 39.6% of congenital heart malformation. 2. The sex distribution of cases were 70 males and 56 females, the age ranged from 13 months to 26 years. 3. Angiographic features seen by axial angiography were as follows: a. Perimembranous defects as seen on long axial view of left ventriculogram were in continuity wity aortic valve. The relation of the defect to the tricuspid valve allows distinction of the extension of the preimembranous defect toward inlet, trabecular, or infundibular zones. This relation was determined angiographically, using the course of the contrast medium from the left ventricle through the ventricular septal defect, opacifying the right ventricle. In inlet excavation, the shunted blood opacified the recess between septal leaflet of tricuspid valve and interventricular septum in early phase, in infundibular excavation, opacified the recess between anterior leaflet of tricuspid valve and anterior free wall of right ventricle and in trabecular excavation, the shunted blood traversed anterior portion of tricuspid valve ring, opacified trabecular portion of right ventricle. b. Muscular defects were separated from the semilunar and atrioventricular valves. c, Subarterial defects were related to both semilunar valves, and they were best demonstrated on the elongated right anterior oblique view of the left ventriculogram. d. Total infundibular defects were profiled in right anterior oblique 30 and long axial view, subaortic in location in both views

  10. The Component And System Reliability Analysis Of Multipurpose Reactor G.A. Subway's Based On The Failure Rate Curve

    Sriyono; Ismu Wahyono, Puradwi; Mulyanto, Dwijo; Kusmono, Siamet

    2001-01-01

    The main component of Multipurpose G.A.Siwabessy had been analyzed by its failure rate curve. The main component ha'..e been analyzed namely, the pump of ''Fuel Storage Pool Purification System'' (AK-AP), ''Primary Cooling System'' (JE01-AP), ''Primary Pool Purification System'' (KBE01-AP), ''Warm Layer System'' (KBE02-AP), ''Cooling Tower'' (PA/D-AH), ''Secondary Cooling System'', and Diesel (BRV). The Failure Rate Curve is made by component database that was taken from 'log book' operation of RSG GAS. The total operation of that curve is 2500 hours. From that curve it concluded that the failure rate of components form of bathtub curve. The maintenance processing causes the curve anomaly

  11. The Effects of Reducing Preparation Time on the Execution of Intentionally Curved Trajectories: Optimization and Geometrical Analysis

    Dovrat Kohen

    2017-06-01

    Full Text Available When subjects are intentionally preparing a curved trajectory, they are engaged in a time-consuming trajectory planning process that is separate from target selection. To investigate the construction of such a plan, we examined the effect of artificially shortening preparation time on the performance of intentionally curved trajectories using the Timed Response task that enforces initiation of movements prematurely. Fifteen subjects performed obstacle avoidance movements toward one of four targets that were presented 25 or 350 ms before the “go” signal, imposing short and long preparation time conditions with mean values of 170 ms and 493 ms, respectively. While trajectories with short preparation times showed target specificity at their onset, they were significantly more variable and showed larger angular deviations from the lines connecting their initial position and the target, compared to the trajectories with long preparation times. Importantly, the trajectories of the short preparation time movements still reached their end-point targets accurately, with comparable movement durations. We hypothesize that success in the short preparation time condition is a result of an online control mechanism that allows further refinement of the plan during its execution and study this control mechanism with a novel trajectory analysis approach using minimum jerk optimization and geometrical modeling approaches. Results show a later agreement of the short preparation time trajectories with the optimal minimum jerk trajectory, accompanied by a later initiation of a parabolic segment. Both observations are consistent with the existence of an online trajectory planning process.Our results suggest that when preparation time is not sufficiently long, subjects execute a more variable and less optimally prepared initial trajectory and exploit online control mechanisms to refine their actions on the fly.

  12. Cone-beam computed tomography analysis of curved root canals after mechanical preparation with three nickel-titanium rotary instruments

    Elsherief, Samia M.; Zayet, Mohamed K.; Hamouda, Ibrahim M.

    2013-01-01

    Cone beam computed tomography is a 3-dimensional high resolution imaging method. The purpose of this study was to compare the effects of 3 different NiTi rotary instruments used to prepare curved root canals on the final shape of the curved canals and total amount of root canal transportation by using cone-beam computed tomography. A total of 81 mesial root canals from 42 extracted human mandibular molars, with a curvature ranging from 15 to 45 degrees, were selected. Canals were randomly divided into 3 groups of 27 each. After preparation with Protaper, Revo-S and Hero Shaper, the amount of transportation and centering ability that occurred were assessed by using cone beam computed tomography. Utilizing pre- and post-instrumentation radiographs, straightening of the canal curvatures was determined with a computer image analysis program. Canals were metrically assessed for changes (surface area, changes in curvature and transportation) during canal preparation by using software SimPlant; instrument failures were also recorded. Mean total widths and outer and inner width measurements were determined on each central canal path and differences were statistically analyzed. The results showed that all instruments maintained the original canal curvature well with no significant differences between the different files (P = 0.226). During preparation there was failure of only one file (the protaper group). In conclusion, under the conditions of this study, all instruments maintained the original canal curvature well and were safe to use. Areas of uninstrumented root canal wall were left in all regions using the various systems. PMID:23885273

  13. The Effects of Reducing Preparation Time on the Execution of Intentionally Curved Trajectories: Optimization and Geometrical Analysis

    Kohen, Dovrat; Karklinsky, Matan; Meirovitch, Yaron; Flash, Tamar; Shmuelof, Lior

    2017-01-01

    When subjects are intentionally preparing a curved trajectory, they are engaged in a time-consuming trajectory planning process that is separate from target selection. To investigate the construction of such a plan, we examined the effect of artificially shortening preparation time on the performance of intentionally curved trajectories using the Timed Response task that enforces initiation of movements prematurely. Fifteen subjects performed obstacle avoidance movements toward one of four targets that were presented 25 or 350 ms before the “go” signal, imposing short and long preparation time conditions with mean values of 170 ms and 493 ms, respectively. While trajectories with short preparation times showed target specificity at their onset, they were significantly more variable and showed larger angular deviations from the lines connecting their initial position and the target, compared to the trajectories with long preparation times. Importantly, the trajectories of the short preparation time movements still reached their end-point targets accurately, with comparable movement durations. We hypothesize that success in the short preparation time condition is a result of an online control mechanism that allows further refinement of the plan during its execution and study this control mechanism with a novel trajectory analysis approach using minimum jerk optimization and geometrical modeling approaches. Results show a later agreement of the short preparation time trajectories with the optimal minimum jerk trajectory, accompanied by a later initiation of a parabolic segment. Both observations are consistent with the existence of an online trajectory planning process.Our results suggest that when preparation time is not sufficiently long, subjects execute a more variable and less optimally prepared initial trajectory and exploit online control mechanisms to refine their actions on the fly. PMID:28706478

  14. Analysis of Fuel Cell Markets in Japan and the US: Experience Curve Development and Cost Reduction Disaggregation

    Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Smith, Sarah J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-07-15

    Fuel cells are both a longstanding and emerging technology for stationary and transportation applications, and their future use will likely be critical for the deep decarbonization of global energy systems. As we look into future applications, a key challenge for policy-makers and technology market forecasters who seek to track and/or accelerate their market adoption is the ability to forecast market costs of the fuel cells as technology innovations are incorporated into market products. Specifically, there is a need to estimate technology learning rates, which are rates of cost reduction versus production volume. Unfortunately, no literature exists for forecasting future learning rates for fuel cells. In this paper, we look retrospectively to estimate learning rates for two fuel cell deployment programs: (1) the micro-combined heat and power (CHP) program in Japan, and (2) the Self-Generation Incentive Program (SGIP) in California. These two examples have a relatively broad set of historical market data and thus provide an informative and international comparison of distinct fuel cell technologies and government deployment programs. We develop a generalized procedure for disaggregating experience-curve cost-reductions in order to disaggregate the Japanese fuel cell micro-CHP market into its constituent components, and we derive and present a range of learning rates that may explain observed market trends. Finally, we explore the differences in the technology development ecosystem and market conditions that may have contributed to the observed differences in cost reduction and draw policy observations for the market adoption of future fuel cell technologies. The scientific and policy contributions of this paper are the first comparative experience curve analysis of past fuel cell technologies in two distinct markets, and the first quantitative comparison of a detailed cost model of fuel cell systems with actual market data. The resulting approach is applicable to

  15. High resolution melting curve analysis, a rapid and affordable method for mutation analysis in childhood acute myeloid leukemia

    Yin eLiu

    2014-09-01

    Full Text Available Background: Molecular genetic alterations with prognostic significance have been described in childhood acute myeloid leukemia (AML. The aim of this study was to establish cost-effective techniques to detect mutations of FMS-like tyrosine kinase 3 (FLT3, Nucleophosmin 1 (NPM1, and a partial tandem duplication within the mixed lineage leukemia (MLL-PTD genes in childhood AML. Procedure: Ninety-nine children with newly diagnosed AML were included in this study. We developed a fluoresent dye SYTO-82 based high resolution melting curve (HRM anaylsis to detect FLT3 internal tandem duplication (FLT3-ITD, FLT3 tyrosine kinase domain (FLT3-TKD and NPM1 mutations. MLL-PTD was screened by real-time quantitative PCR. Results: The HRM methodology correlated well with gold standard Sanger sequencing with less cost. Among the 99 patients studied, the FLT3-ITD mutation was associated with significantly worse event free survival (EFS. Patients with the NPM1 mutation had significantly better EFS and overall survival. However, HRM was not sensitive enough for minimal residual disease monitoring. Conclusions: HRM was a rapid and efficient method for screening of FLT3 and NPM1 gene mutations. It was both affordable and accurate, especially in resource underprivileged regions. Our results indicated that HRM could be a useful clinical tool for rapid and cost effective screening of the FLT3 and NPM1 mutations in AML patients.

  16. Detection of diarrheagenic Escherichia coli by use of melting-curve analysis and real-time multiplex PCR.

    Guion, Chase E; Ochoa, Theresa J; Walker, Christopher M; Barletta, Francesca; Cleary, Thomas G

    2008-05-01

    Diarrheagenic Escherichia coli strains are important causes of diarrhea in children from the developing world and are now being recognized as emerging enteropathogens in the developed world. Current methods of detection are too expensive and labor-intensive for routine detection of these organisms to be practical. We developed a real-time fluorescence-based multiplex PCR for the detection of all six of the currently recognized classes of diarrheagenic E. coli. The primers were designed to specifically amplify eight different virulence genes in the same reaction: aggR for enteroaggregative E. coli, stIa/stIb and lt for enterotoxigenic E. coli, eaeA for enteropathogenic E. coli and Shiga toxin-producing E. coli (STEC), stx(1) and stx(2) for STEC, ipaH for enteroinvasive E. coli, and daaD for diffusely adherent E. coli (DAEC). Eighty-nine of ninety diarrheagenic E. coli and 36/36 nonpathogenic E. coli strains were correctly identified using this approach (specificity, 1.00; sensitivity, 0.99). The single false negative was a DAEC strain. The total time between preparation of DNA from E. coli colonies on agar plates and completion of PCR and melting-curve analysis was less than 90 min. The cost of materials was low. Melting-point analysis of real-time multiplex PCR is a rapid, sensitive, specific, and inexpensive method for detection of diarrheagenic E. coli.

  17. First-order-reversal-curve analysis of exchange-coupled SmCo/NdFeB nanocomposite alloys

    Pan, Mingxiang; Zhang, Pengyue; Ge, Hongliang; Yu, Nengjun; Wu, Qiong

    2014-01-01

    Exchange-coupled SmCo 5 /Nd 2 Fe 14 B nanocomposite magnets have been fabricated by ball milling of the micrometer sized SmCo 5 and Nd 2 Fe 14 B powders. The influence of Nd 2 Fe 14 B content on the microstructure and magnetic properties of these hybrid alloys was investigated. The alloys that show strong intergrain exchange-coupling behavior with (BH) max =2.95 MGOe was obtained when the two hard phases are well coupled. A first-order-reversal-curve (FORC) analysis was performed for both SmCo 5 single-phase magnet and SmCo 5 /Nd 2 Fe 14 B hybrid magnet; the FORC diagrams results show two major peaks for the hybrid magnets. In both cases, the magnetization reversal behaviors for these alloys were discussed in detail and are consistent with the results of δM plots. - Highlights: • Exchange-coupled SmCo 5 /Nd 2 Fe 14 B nanocomposite magnets were studied. • Magnetization reversal behaviors of the hybrid magnet were discussed. • The FORCs analysis is taken to identify the optimal conditions for hybrid magnet

  18. The use of conservation supply curves in energy policy and economic analysis: The case study of Thai cement industry

    Hasanbeigi, Ali; Menke, Christoph; Therdyothin, Apichit

    2010-01-01

    The cement industry is one of the largest energy-consuming industries in Thailand with high carbon dioxide (CO 2 ) emissions. Using a bottom-up electricity Conservation Supply Curve (CSC) model, the cost effective and the total technical electricity-efficiency potential for the Thai cement industry in 2008 is estimated to be about 265 and 1697 gigawatt-hours (GWh) which account for 8% and 51% of the total electricity used in the cement industry in 2005, respectively. The fuel CSC model shows the cost-effective fuel-efficiency potential to be 17,214 terajoules (TJ) and the total technical fuel-efficiency potential equal to 21,202 TJ, accounting for 16% and 19% of the total fuel used in cement industry in 2005, respectively. The economic analysis in this paper shows how the information from the CSCs can be used to calculate the present value (PV) of net cost savings over a period of time taking into account the energy price escalation rate. The results from the policy scenario analysis show that the most effective and efficient policy scenario is the introduction of an energy-related CO 2 tax for the cement industry under a voluntary agreement program. This scenario results in 16.9% primary energy-efficiency improvement over a 5-year implementation period.

  19. First-order-reversal-curve analysis of exchange-coupled SmCo/NdFeB nanocomposite alloys

    Pan, Mingxiang; Zhang, Pengyue, E-mail: Zhang_pengyue@cjlu.edu.cn; Ge, Hongliang; Yu, Nengjun; Wu, Qiong

    2014-06-01

    Exchange-coupled SmCo{sub 5}/Nd{sub 2}Fe{sub 14}B nanocomposite magnets have been fabricated by ball milling of the micrometer sized SmCo{sub 5} and Nd{sub 2}Fe{sub 14}B powders. The influence of Nd{sub 2}Fe{sub 14}B content on the microstructure and magnetic properties of these hybrid alloys was investigated. The alloys that show strong intergrain exchange-coupling behavior with (BH){sub max}=2.95 MGOe was obtained when the two hard phases are well coupled. A first-order-reversal-curve (FORC) analysis was performed for both SmCo{sub 5} single-phase magnet and SmCo{sub 5}/Nd{sub 2}Fe{sub 14}B hybrid magnet; the FORC diagrams results show two major peaks for the hybrid magnets. In both cases, the magnetization reversal behaviors for these alloys were discussed in detail and are consistent with the results of δM plots. - Highlights: • Exchange-coupled SmCo{sub 5}/Nd{sub 2}Fe{sub 14}B nanocomposite magnets were studied. • Magnetization reversal behaviors of the hybrid magnet were discussed. • The FORCs analysis is taken to identify the optimal conditions for hybrid magnet.

  20. Analysis of glow curve of GaS{sub 0.5}Se{sub 0.5} single crystals

    Isik, Mehmet, E-mail: mehmet.isik@atilim.edu.tr [Department of Electrical and Electronics Engineering, Atilim University, 06836 Ankara (Turkey); Delice, Serdar [Department of Physics, Middle East Technical University, 06800 Ankara (Turkey); Gasanly, Nizami [Department of Physics, Middle East Technical University, 06800 Ankara (Turkey); Virtual International Scientific Research Centre, Baku State University, 1148 Baku (Azerbaijan)

    2015-12-15

    Characterization of shallow trapping centers in GaS{sub 0.5}Se{sub 0.5} crystals grown by a Bridgman method was carried out in the present work using thermoluminescence (TL) measurements performed in the low temperature range of 10–300 K. The activation energies of the trapping centers were obtained under the light of results of various analysis methods. The presence of three trapping centers located at 6, 30 and 72 meV was revealed. The analysis of the experimental glow curve gave reasonable results under the model that assumes slow retrapping which states the order of kinetics as b=1. Heating rate dependence of the observed TL peaks was studied for the rates between 0.4 and 1.0 K/s. Distribution of the traps was also investigated using an experimental technique based on the thermal cleaning of centers giving emission at lower temperatures. The distributed levels with activation energies increasing from 6 to 136 meV were revealed by increasing the stopping temperature from 10 to 52 K. - Highlights: • TL measurements were performed in the 10–300 K range on GaS{sub 0.5}Se{sub 0.5} crystals. • Atomic composition ratio of the elements was found. • Three trapping centers located at 6, 30 and 72 meV were revealed. • Distribution of trapping centers was studied on as-grown crystal.

  1. Power Curve Measurements

    Federici, Paolo; Kock, Carsten Weber

    This report describes the power curve measurements performed with a nacelle LIDAR on a given wind turbine in a wind farm and during a chosen measurement period. The measurements and analysis are carried out in accordance to the guidelines in the procedure “DTU Wind Energy-E-0019” [1]. The reporting...

  2. Nacelle lidar power curve

    Gómez Arranz, Paula; Wagner, Rozenn

    This report describes the power curve measurements performed with a nacelle LIDAR on a given wind turbine in a wind farm and during a chosen measurement period. The measurements and analysis are carried out in accordance to the guidelines in the procedure “DTU Wind Energy-E-0019” [1]. The reporting...

  3. Signature Curves Statistics of DNA Supercoils

    Shakiban, Cheri; Lloyd, Peter

    2004-01-01

    In this paper we describe the Euclidean signature curves for two dimensional closed curves in the plane and their generalization to closed space curves. The focus will be on discrete numerical methods for approximating such curves. Further we will apply these numerical methods to plot the signature curves related to three-dimensional simulated DNA supercoils. Our primary focus will be on statistical analysis of the data generated for the signature curves of the supercoils. We will try to esta...

  4. Chest pain in patients with arterial hypertension, angiographically normal coronary arteries and stiff aorta: the aortic pain syndrome.

    Stakos, Dimitrios A; Tziakas, Dimitrios N; Chalikias, George; Mitrousi, Konstantina; Tsigalou, Christina; Boudoulas, Harisios

    2013-01-01

    Arterial hypertension is often associated with a stiff aorta as a result of collagen accumulation in the aortic wall and may produce chest pain. In the present study, possible interrelationships between aortic function, collagen turnover and exercise-induced chest pain in patients with arterial hypertension and angiographically normal coronary arteries were investigated. Ninety-seven patients with arterial hypertension, angiographically normal coronary arteries and no evidence of myocardial ischemia on nuclear cardiac imaging during exercise test were studied. Of these, 43 developed chest pain during exercise (chest pain group) while 54 did not (no chest pain group). Carotid femoral pulse-wave velocity (PWVc-f) was used to assess the elastic properties of the aorta. Amino-terminal pro-peptides of pro-collagen type I, (PINP, reflecting collagen synthesis), serum telopeptides of collagen type I (CITP, reflecting collagen degradation), pro-metalloproteinase 1 (ProMMP-1), and tissue inhibitor of metalloproteinase 1 (TIMP-1, related to collagen turnover) were measured in plasma by immunoassay. The chest pain group had higher PWVc-f, higher and /CITP ratio, and lower proMMP-1/ TIMP-1 ratio compared to the no chest pain group. PWVc-f (t=2.53, p=0.02) and PINP (t=2.42, p=0.02) were independently associated with the presence of chest pain in multiple regression analysis. Patients with arterial hypertension, exercise-induced chest pain and angiographically normal coronary arteries, without evidence of exercise-induced myocardial ischemia, had a stiffer aorta compared to those without chest pain. Alterations in collagen type I turnover that favor collagen accumulation in the aortic wall may contribute to aortic stiffening and chest pain in these patients.

  5. The selective angiographic diagnosis and endovascular embolization treatment of severe epistaxis

    Zhang Xiquan; Lu Yonghong; Sun Jinghua; Guo Deqiang; Li Yuzhen; Wei Aihua

    2002-01-01

    Objective: To evaluate selective angiographic diagnosis and embolization of severe epistaxis in 57 cases. Methods: 41 cases with spontaneous haemorrhage, 11 cases with traumatic haemorrhage, 3 cases with haemorrhage of nasopharyngeal fibroangioma, and 2 case with haemorrhage of nasopharyngeal carcinoma were included in the study. Selective angiographic diagnosis and embolization of epistaxis were performed with absorbable gelatin sponge or balloon or spring coil by using Seldinger's method. Results: 59 procedure of angiographic diagnosis and embolization were performed in 57 cases. Both maxillaris internal artery embolization was performed in 6 cases. After embolization, satisfactory results were achieved immediately in 55 cases. After 6 months to 2 years' follow-up, no haemorrhage recurred. In 4 cases with traumatic haemorrhage in the face, simple maxillaris internal artery embolization was performed in 2 cases. Conclusion: Selective angiographic diagnosis and embolization are safe, effective, and successful method of choices in the treatment of severe epistaxis

  6. Application of dissociation curve analysis to radiation hybrid panel marker scoring: generation of a map of river buffalo (B. bubalis chromosome 20

    Schäffer Alejandro A

    2008-11-01

    Full Text Available Abstract Background Fluorescence of dyes bound to double-stranded PCR products has been utilized extensively in various real-time quantitative PCR applications, including post-amplification dissociation curve analysis, or differentiation of amplicon length or sequence composition. Despite the current era of whole-genome sequencing, mapping tools such as radiation hybrid DNA panels remain useful aids for sequence assembly, focused resequencing efforts, and for building physical maps of species that have not yet been sequenced. For placement of specific, individual genes or markers on a map, low-throughput methods remain commonplace. Typically, PCR amplification of DNA from each panel cell line is followed by gel electrophoresis and scoring of each clone for the presence or absence of PCR product. To improve sensitivity and efficiency of radiation hybrid panel analysis in comparison to gel-based methods, we adapted fluorescence-based real-time PCR and dissociation curve analysis for use as a novel scoring method. Results As proof of principle for this dissociation curve method, we generated new maps of river buffalo (Bubalus bubalis chromosome 20 by both dissociation curve analysis and conventional marker scoring. We also obtained sequence data to augment dissociation curve results. Few genes have been previously mapped to buffalo chromosome 20, and sequence detail is limited, so 65 markers were screened from the orthologous chromosome of domestic cattle. Thirty bovine markers (46% were suitable as cross-species markers for dissociation curve analysis in the buffalo radiation hybrid panel under a standard protocol, compared to 25 markers suitable for conventional typing. Computational analysis placed 27 markers on a chromosome map generated by the new method, while the gel-based approach produced only 20 mapped markers. Among 19 markers common to both maps, the marker order on the map was maintained perfectly. Conclusion Dissociation curve

  7. Pulse wave analysis in a 180-degree curved artery model: Implications under physiological and non-physiological inflows

    Bulusu, Kartik V.; Plesniak, Michael W.

    2013-11-01

    Systolic and diastolic blood pressures, pulse pressures, and left ventricular hypertrophy contribute to cardiovascular risks. Increase of arterial stiffness due to aging and hypertension is an important factor in cardiovascular, chronic kidney and end-stage-renal-diseases. Pulse wave analysis (PWA) based on arterial pressure wave characteristics, is well established in clinical practice for evaluation of arterial distensibility and hypertension. The objective of our exploratory study in a rigid 180-degree curved artery model was to evaluate arterial pressure waveforms. Bend upstream conditions were measured using a two-component, two-dimensional, particle image velocimeter (2C-2D PIV). An ultrasonic transit-time flow meter and a catheter with a MEMS-based solid state pressure sensor, capable of measuring up to 20 harmonics of the observed pressure waveform, monitored flow conditions downstream of the bend. Our novel continuous wavelet transform algorithm (PIVlet 1.2), in addition to detecting coherent secondary flow structures is used to evaluate arterial pulse wave characteristics subjected to physiological and non-physiological inflows. Results of this study will elucidate the utility of wavelet transforms in arterial function evaluation and pulse wave speed. Supported by NSF Grant No. CBET- 0828903 and GW Center for Biomimetics and Bioinspired Engineering.

  8. Sensitivity analysis of the electrostatic force distance curve using Sobol’s method and design of experiments

    Alhossen, I; Bugarin, F; Segonds, S; Villeneuve-Faure, C; Baudoin, F

    2017-01-01

    Previous studies have demonstrated that the electrostatic force distance curve (EFDC) is a relevant way of probing injected charge in 3D. However, the EFDC needs a thorough investigation to be accurately analyzed and to provide information about charge localization. Interpreting the EFDC in terms of charge distribution is not straightforward from an experimental point of view. In this paper, a sensitivity analysis of the EFDC is studied using buried electrodes as a first approximation. In particular, the influence of input factors such as the electrode width, depth and applied potential are investigated. To reach this goal, the EFDC is fitted to a law described by four parameters, called logistic law, and the influence of the electrode parameters on the law parameters has been investigated. Then, two methods are applied—Sobol’s method and the factorial design of experiment—to quantify the effect of each factor on each parameter of the logistic law. Complementary results are obtained from both methods, demonstrating that the EFDC is not the result of the superposition of the contribution of each electrode parameter, but that it exhibits a strong contribution from electrode parameter interaction. Furthermore, thanks to these results, a matricial model has been developed to predict EFDCs for any combination of electrode characteristics. A good correlation is observed with the experiments, and this is promising for charge investigation using an EFDC. (paper)

  9. Sensitivity analysis of the electrostatic force distance curve using Sobol’s method and design of experiments

    Alhossen, I.; Villeneuve-Faure, C.; Baudoin, F.; Bugarin, F.; Segonds, S.

    2017-01-01

    Previous studies have demonstrated that the electrostatic force distance curve (EFDC) is a relevant way of probing injected charge in 3D. However, the EFDC needs a thorough investigation to be accurately analyzed and to provide information about charge localization. Interpreting the EFDC in terms of charge distribution is not straightforward from an experimental point of view. In this paper, a sensitivity analysis of the EFDC is studied using buried electrodes as a first approximation. In particular, the influence of input factors such as the electrode width, depth and applied potential are investigated. To reach this goal, the EFDC is fitted to a law described by four parameters, called logistic law, and the influence of the electrode parameters on the law parameters has been investigated. Then, two methods are applied—Sobol’s method and the factorial design of experiment—to quantify the effect of each factor on each parameter of the logistic law. Complementary results are obtained from both methods, demonstrating that the EFDC is not the result of the superposition of the contribution of each electrode parameter, but that it exhibits a strong contribution from electrode parameter interaction. Furthermore, thanks to these results, a matricial model has been developed to predict EFDCs for any combination of electrode characteristics. A good correlation is observed with the experiments, and this is promising for charge investigation using an EFDC.

  10. Integrity of Literature on Expressed Emotion and Relapse in Patients with Schizophrenia Verified by a p-Curve Analysis.

    Weintraub, Marc J; Hall, Daniel L; Carbonella, Julia Y; Weisman de Mamani, Amy; Hooley, Jill M

    2017-06-01

    There is growing concern that much published research may have questionable validity due to phenomena such as publication bias and p-hacking. Within the psychiatric literature, the construct of expressed emotion (EE) is widely assumed to be a reliable predictor of relapse across a range of mental illnesses. EE is an index of the family climate, measuring how critical, hostile, and overinvolved a family member is toward a mentally ill patient. No study to date has examined the evidential value of this body of research as a whole. That is to say, although many studies have shown a link between EE and symptom relapse, the integrity of the literature from which this claim is derived has not been tested. In an effort to confirm the integrity of the literature of EE predicting psychiatric relapse in patients with schizophrenia, we conducted a p-curve analysis on all known studies examining EE (using the Camberwell Family Interview) to predict psychiatric relapse over a 9- to 12-month follow-up period. Results suggest that the body of literature on EE is unbiased and has integrity, as there was a significant right skew of p-values, a nonsignificant left skew of p-values, and a nonsignificant test of flatness. We conclude that EE is a robust and valuable predictor of symptom relapse in schizophrenia. © 2016 Family Process Institute.

  11. Cooling Curve Analysis of Micro- and Nanographite Particle-Embedded Salt-PCMs for Thermal Energy Storage Applications

    Sudheer, R.; Prabhu, K. N.

    2017-08-01

    In recent years, the focus of phase change materials (PCM) research was on the development of salt mixtures with particle additives to improve their thermal energy storage (TES) functionalities. The effect of addition of microsized (50 μm) and nanosized (400 nm) graphite particles on TES parameters of potassium nitrate was analyzed in this work. A novel technique of computer-aided cooling curve analysis was employed here to study the suitability of large inhomogeneous PCM samples. The addition of graphite micro- and nanoparticles reduced the solidification time of the PCM significantly enhancing the heat removal rates, in the first thermal cycle. The benefits of dispersing nanoparticles diminished in successive 10 thermal cycles, and its performance was comparable to the microparticle-embedded PCM thereafter. The decay of TES functionalities on thermal cycling is attributed to the agglomeration of nanoparticles which was observed in SEM images. The thermal diffusivity property of the PCM decreased with addition of graphite particles. With no considerable change in the cooling rates and a simultaneous decrease in thermal diffusivity, it is concluded that the addition of graphite particles increased the specific heat capacity of the PCM. It is also suggested that the additive concentration should not be greater than 0.1% by weight of the PCM sample.

  12. A Data-driven Study of RR Lyrae Near-IR Light Curves: Principal Component Analysis, Robust Fits, and Metallicity Estimates

    Hajdu, Gergely; Dékány, István; Catelan, Márcio; Grebel, Eva K.; Jurcsik, Johanna

    2018-04-01

    RR Lyrae variables are widely used tracers of Galactic halo structure and kinematics, but they can also serve to constrain the distribution of the old stellar population in the Galactic bulge. With the aim of improving their near-infrared photometric characterization, we investigate their near-infrared light curves, as well as the empirical relationships between their light curve and metallicities using machine learning methods. We introduce a new, robust method for the estimation of the light-curve shapes, hence the average magnitudes of RR Lyrae variables in the K S band, by utilizing the first few principal components (PCs) as basis vectors, obtained from the PC analysis of a training set of light curves. Furthermore, we use the amplitudes of these PCs to predict the light-curve shape of each star in the J-band, allowing us to precisely determine their average magnitudes (hence colors), even in cases where only one J measurement is available. Finally, we demonstrate that the K S-band light-curve parameters of RR Lyrae variables, together with the period, allow the estimation of the metallicity of individual stars with an accuracy of ∼0.2–0.25 dex, providing valuable chemical information about old stellar populations bearing RR Lyrae variables. The methods presented here can be straightforwardly adopted for other classes of variable stars, bands, or for the estimation of other physical quantities.

  13. Power Curve Measurements REWS

    Gómez Arranz, Paula; Vesth, Allan

    This report describes the power curve measurements carried out on a given wind turbine in a chosen period. The measurements were carried out following the measurement procedure in the draft of IEC 61400-12-1 Ed.2 [1], with some deviations mostly regarding uncertainty calculation. Here, the refere......This report describes the power curve measurements carried out on a given wind turbine in a chosen period. The measurements were carried out following the measurement procedure in the draft of IEC 61400-12-1 Ed.2 [1], with some deviations mostly regarding uncertainty calculation. Here......, the reference wind speed used in the power curve is the equivalent wind speed obtained from lidar measurements at several heights between lower and upper blade tip, in combination with a hub height meteorological mast. The measurements have been performed using DTU’s measurement equipment, the analysis...

  14. Angiographic Findings and Embolotherapy in Renal Arterial Trauma

    Sofocleous, Constantinos T.; Hinrichs, Clay; Hubbi, Basil; Brountzos, Elias; Kaul, Sanjeev; Kannarkat, George; Bahramipour, Philip; Barone, Alison; Contractor, Daniel G.; Shah, Tanmaya

    2005-01-01

    Purpose To evaluate the angiographic findings and embolotherapy in the management of traumatic renal arterial injury Methods This is a retrospective review of 22 patients with renal trauma who underwent arteriography and percutaneous embolization from December 1995 to January 2002. Medical records, imaging studies and procedural reports were reviewed to assess the type of injury, arteriographic findings and immediate embolization results. Long-term clinical outcome was obtained by communication with the trauma physicians and by clinical chart review.Results Arteriography was performed in 125 patients admitted to a State Trauma Center with suspected internal bleeding. Renal arterial injury was documented in 22 and was the result of a motor-vehicle accident (10), auto-pedestrian accident (1), gunshot (4) or stab wounds (6) and a fall (1). Percutaneous renal arterial embolization was undertaken in 22 of 125 (18%) patients to treat extravasation (11), arterial pedicle rupture (5), abnormal arteriovenous (3) or arteriocalyceal (2) communication and pseudoaneurysm (3). One of the pseudoaneurysms and one of the arteriovenous fistulae were found in addition to extravasation. All 22 patients (16 men, 6 women) were hemodynamically stable, or controlled during arteriography and embolotherapy. Selective and/or superselective embolization of the abnormal vessels was performed using coils in 9 patients, microcoils in 9 patients and Gelfoam pledgets in 3 patients. In one patient Gelfoam pledgets mixed with polyvinyl alcohol (PVA) particles were used for embolization. Immediate angiographic evidence of hemostasis was demonstrated in all cases. Two initial technical failures were treated with repeat arteriography and embolization. There was no procedure-related death. There was no non-target embolization. One episode of renal abscess after embolization was treated by nephrectomy and 3 patients underwent elective post-embolization nephrectomy to prevent infection. Follow-up ranged

  15. The subtype of VSD and the angiographic differentiation

    Choe, Kyu Ok; Sul, Jun Hee; Lee, Sung Kyu; Cho, Bum Koo; Hong, Sung Nok

    1985-01-01

    VSD is the most common congenital cardiac malformation and the natural history depends not only on the age of patients and the size of defect but the subtype of VSD as well, important factor in clinical management of those patients. In 110 patients, with surgically repaired VSD in Yonsei Medical Center in 1984, the subtype of VSDs evaluated by surgical observation were correlated with LV angiogram findings to verify the incidence of subtype in Korean and the diagnostic accuracy to predict the subtype by angiogram. 1. 110 patients included 64 boys and 46 girls, the age ranged from 3 months to 14 years (average 4.6 years old). 2. Angiographic findings were interpreted as follows; a. Perimembranous defects were profiled in LAO 60 .deg. LV angiogram and located below the aortic valve. In inlet excavation the shunted blood opacified the recess between septal leaflet of tricuspid valve and interventricular septum in early phase, in infundibular excavation opacified the recess between anterior leaflet of TV and anterior free wall of RV and in trabecular excavation the shunted blood traversed anterior portion of TV ring, opacified trabecular portion of RV cavity. b. Subarterial types were profiled in RAO 30 .deg. LV angiogram, just below aortic valve as well as pulmonic valve. Total infundibular defects were profiled in RAO 30 .deg. and LAO 60 .deg. LV angiogram subaortic in location in both views. c. In muscular VSD the profiled angle was varied according to the subtype but the defects were separated from the aortic valve as muscular septum interposed between the aortic valve and the defect. 3. The incidence of subtype of VSDs evaluated by surgical observation were as follows. Subarterial type : 32 cases (29.1%) Total infundibular defect : 5 cases (4.5%) Perimembranous type : 73 cases (66.3%) Infundibular excavation : 32 cases (29.2%) Trabecular excavation : 28 cases (25.5%) Inlet excavation : 10 cases (9.1%) Mixed : 3 cases (2.7%) Muscular type : 1 cases (0.9%) Total 63

  16. Optimal Threshold Determination for Discriminating Driving Anger Intensity Based on EEG Wavelet Features and ROC Curve Analysis

    Ping Wan

    2016-08-01

    Full Text Available Driving anger, called “road rage”, has become increasingly common nowadays, affecting road safety. A few researches focused on how to identify driving anger, however, there is still a gap in driving anger grading, especially in real traffic environment, which is beneficial to take corresponding intervening measures according to different anger intensity. This study proposes a method for discriminating driving anger states with different intensity based on Electroencephalogram (EEG spectral features. First, thirty drivers were recruited to conduct on-road experiments on a busy route in Wuhan, China where anger could be inducted by various road events, e.g., vehicles weaving/cutting in line, jaywalking/cyclist crossing, traffic congestion and waiting red light if they want to complete the experiments ahead of basic time for extra paid. Subsequently, significance analysis was used to select relative energy spectrum of β band (β% and relative energy spectrum of θ band (θ% for discriminating the different driving anger states. Finally, according to receiver operating characteristic (ROC curve analysis, the optimal thresholds (best cut-off points of β% and θ% for identifying none anger state (i.e., neutral were determined to be 0.2183 ≤ θ% < 1, 0 < β% < 0.2586; low anger state is 0.1539 ≤ θ% < 0.2183, 0.2586 ≤ β% < 0.3269; moderate anger state is 0.1216 ≤ θ% < 0.1539, 0.3269 ≤ β% < 0.3674; high anger state is 0 < θ% < 0.1216, 0.3674 ≤ β% < 1. Moreover, the discrimination performances of verification indicate that, the overall accuracy (Acc of the optimal thresholds of β% for discriminating the four driving anger states is 80.21%, while 75.20% for that of θ%. The results can provide theoretical foundation for developing driving anger detection or warning devices based on the relevant optimal thresholds.

  17. Detecting differential allelic expression using high-resolution melting curve analysis: application to the breast cancer susceptibility gene CHEK2

    Sinilnikova Olga

    2011-05-01

    Full Text Available Abstract Background The gene CHEK2 encodes a checkpoint kinase playing a key role in the DNA damage pathway. Though CHEK2 has been identified as an intermediate breast cancer susceptibility gene, only a small proportion of high-risk families have been explained by genetic variants located in its coding region. Alteration in gene expression regulation provides a potential mechanism for generating disease susceptibility. The detection of differential allelic expression (DAE represents a sensitive assay to direct the search for a functional sequence variant within the transcriptional regulatory elements of a candidate gene. We aimed to assess whether CHEK2 was subject to DAE in lymphoblastoid cell lines (LCLs from high-risk breast cancer patients for whom no mutation in BRCA1 or BRCA2 had been identified. Methods We implemented an assay based on high-resolution melting (HRM curve analysis and developed an analysis tool for DAE assessment. Results We observed allelic expression imbalance in 4 of the 41 LCLs examined. All four were carriers of the truncating mutation 1100delC. We confirmed previous findings that this mutation induces non-sense mediated mRNA decay. In our series, we ruled out the possibility of a functional sequence variant located in the promoter region or in a regulatory element of CHEK2 that would lead to DAE in the transcriptional regulatory milieu of freely proliferating LCLs. Conclusions Our results support that HRM is a sensitive and accurate method for DAE assessment. This approach would be of great interest for high-throughput mutation screening projects aiming to identify genes carrying functional regulatory polymorphisms.

  18. Identification of squid species by melting temperature shifts on fluorescence melting curve analysis (FMCA) using single dual-labeled probe

    Koh, Eunjung; Song, Ha Jeong; Kwon, Na Young; Kim, Gi Won; Lee, Kwang Ho; Jo, Soyeon; Park, Sujin; Park, Jihyun; Park, Eun Kyeong; Hwang, Seung Yong

    2017-06-01

    Real time PCR is a standard method for identification of species. One of limitations of the qPCR is that there would be false-positive result due to mismatched hybridization between target sequence and probe depending on the annealing temperature in the PCR condition. As an alternative, fluorescence melting curve analysis (FMCA) could be applied for species identification. FMCA is based on a dual-labeled probe. Even with subtle difference of target sequence, there are visible melting temperature (Tm) shift. One of FMCA applications is distinguishing organisms distributed and consumed globally as popular food ingredients. Their prices are set by species or country of origin. However, counterfeiting or distributing them without any verification procedure are becoming social problems and threatening food safety. Besides distinguishing them in naked eye is very difficult and almost impossible in any processed form. Therefore, it is necessary to identify species in molecular level. In this research three species of squids which have 1-2 base pair differences each are selected as samples since they have the same issue. We designed a probe which perfectly matches with one species and the others mismatches 2 and 1 base pair respectively and labeled with fluorophore and quencher. In an experiment with a single probe, we successfully distinguished them by Tm shift depending on the difference of base pair. By combining FMCA and qPCR chip, smaller-scale assay with higher sensitivity and resolution could be possible, andc furthermore, enabling results analysis with smart phone would realize point-of-care testing (POCT).

  19. Effect of transcatheter arterial embolization according to angiographic findings in hepatocellular carcinoma

    Wang, Chi Hyung; Shim, Hyung Jin; Lee, Jong Ik; Yu, Hyun; Kim, Young Goo; Lee, Jong Beum; Kim, Kun Sang

    1994-01-01

    The purpose of this study is to assess the effect of Transcatheter Arterial Embolization(TAE) according to angiographic findings in hepatocellular carcinoma. We retrospectively reviewed 50 cases who received TAE for unresectable hepatocellular carcinoma. We analyzed the angiographic findings which were correlated with the effect of TAE. The common angiographic findings of the hepatocellular carcinoma were tumor staining, neo vascularity and enlargement of feeding artery. These angiographic findings were classified into grade 0, +1, +2. Effect of TAE were classified into five patterns; good response, partial response, minimal response, no response and more aggravation. In grading of tumor staining, among 50 cases, the grade 0, +1, +2 were seen in 1 case(2%), 14 cases(28%), 35 cases(70%) each. In grading of enlargement of feeding artery, the grade 0, +1, +2 were seen in 7 cases(14%), 19 cases(38%), 24 cases(48%) each. In grading of neo vascularity, the grade 0, +1, +2 were seen in 6 cases(12%), 15 cases(30%), 29 cases(58%) each. This study showed that the higher grade of angiographic finding, the better effect of TAE. A statistically significant difference was found (P<0.005). But the TAE was not effective in some cases (the maximum diameter of mass is over 10cm, portal vein thrombosis or arteriovenous shunt) in spite of high grade. We believe that these angiographic findings (tumor staining, enlargement of feeding artery, neo vascularity) are one of important indices for anticipating the effect of TAE in patients with unresectable hepatocellular carcinoma

  20. Two Aspects of the Simplex Model: Goodness of Fit to Linear Growth Curve Structures and the Analysis of Mean Trends.

    Mandys, Frantisek; Dolan, Conor V.; Molenaar, Peter C. M.

    1994-01-01

    Studied the conditions under which the quasi-Markov simplex model fits a linear growth curve covariance structure and determined when the model is rejected. Presents a quasi-Markov simplex model with structured means and gives an example. (SLD)

  1. Crashes and near-crashes on horizontal curves along rural two-lane highways: Analysis of naturalistic driving data.

    Wang, Bo; Hallmark, Shauna; Savolainen, Peter; Dong, Jing

    2017-12-01

    Prior research has shown the probability of a crash occurring on horizontal curves to be significantly higher than on similar tangent segments, and a disproportionally higher number of curve-related crashes occurred in rural areas. Challenges arise when analyzing the safety of horizontal curves due to imprecision in integrating information as to the temporal and spatial characteristics of each crash with specific curves. The second Strategic Highway Research Program(SHRP 2) conducted a large-scale naturalistic driving study (NDS),which provides a unique opportunity to better understand the contributing factors leading to crash or near-crash events. This study utilizes high-resolution behavioral data from the NDS to identify factors associated with 108 safety critical events (i.e., crashes or near-crashes) on rural two-lane curves. A case-control approach is utilized wherein these events are compared to 216 normal, baseline-driving events. The variables examined in this study include driver demographic characteristics, details of the traffic environment and roadway geometry, as well as driver behaviors such as in-vehicle distractions. Logistic regression models are estimated to discern those factors affecting the likelihood of a driver being crash-involved. These factors include high-risk behaviors, such as speeding and visual distractions, as well as curve design elements and other roadway characteristics such as pavement surface conditions. This paper successfully integrated driver behavior, vehicle characteristics, and roadway environments into the same model. Logistic regression model was found to be an effective way to investigate crash risks using naturalistic driving data. This paper revealed a number of contributing factors to crashes on rural two-lane curves, which has important implications in traffic safety policy and curve geometry design. This paper also discussed limitations and lessons learned from working with the SHRP 2 NDS data. It will benefit

  2. Evaluation of the angiographic findings in pulmonary atresia

    Choe, Kyu Ok; Sul, Jun Hee; Lee, Seung Kyu; Cho, Bum Koo; Hong, Pill Whoon

    1986-01-01

    We studied the angiographic findings in 65 patients with congenital pulmonary atresia, ages 4 days to 14 years (mean 3.3 yrs), from 1981 to 1986 at Severance Hospital Yonsei University. 1. 6 had pulmonary atresia with an intact interventricular septum, 38 had it with cardiac anomaly Renodynamically simulating TOF, and 21 associated with more complicated cardiac anomalies. 2. In the group with an intact ventricular septum, 5 showed confluent intrapericardial pulmonary artery, all segmental pulmonary arteries connected to intrapericardial artery. 3. In the group simulating TOF, aorta arose from RV with or without overriding in 35. In 27 patients with confluent intrapericardial pulmonary artery, 23 had more than 10 segmental pulmonary arteries connected to intrapericardial artery and 5 had severely hypoplastic hilar pulmonary arteries. In 11 with non confluent intrapericardial pulmonary artery, 4 had more than 10 segmental pulmonary arteries connected to central pulmonary artery and 9 had severely hypoplastic hilar pulmonary arteries. 4. In the group associated with more complicated cardiac anomaly, included 8 patients with atrioventricular discordance, 7 with univentricular heart and 6 with tricuspid atresia. In 17 patients with confluent intrapericardial artery, 16 had more than 10 segmental pulmonary arteries connected to intrapericardial artery, one showed severe hypoplasia of hilar pulmonary arteries. In another 4 with non confluence, no one showed more than 10 segmental arteries connected to intrapericardial or hilar pulmonary artery.

  3. Percutaneous vertebroplasty with a high-quality rotational angiographic unit

    Pedicelli, Alessandro [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: apedicelli@rm.unicatt.it; Rollo, Massimo [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: mrollo@rm.unicatt.it; Piano, Mariangela [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: mariangela.piano@gmail.com; Re, Thomas J. [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: tomjre@gmail.com; Cipriani, Maria C. [Department of Gerontology, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: alexped@yahoo.com; Colosimo, Cesare [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: colosimo@rm.unicatt.it; Bonomo, Lorenzo [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: lbonomo@rm.unicatt.it

    2009-02-15

    We evaluated the reliability of a rotational angiographic unit (RA) with flat-panel detector as a single technique to guide percutaneous vertebroplasty (PVP) and for post-procedure assessment by 2D and 3D reformatted images. Fifty-five consecutive patients (104 vertebral bodies) were treated under RA fluoroscopy. Rotational acquisitions with 2D and 3D reconstruction were obtained in all patients for immediate post-procedure assessment. In complex cases, this technique was also used to evaluate the needle position during the procedure. All patients underwent CT scan after the procedure. RA and CT findings were compared. In all cases, a safe trans-pedicular access and an accurate control of the bone-cement injection were successfully performed with high-quality fluoroscopy, even at the thoracic levels and in case of vertebra plana. 2D and 3D rotational reconstructions permitted CT-like images that clearly showed needle position and were similar to CT findings in depicting intrasomatic implant-distribution. RA detected 40 cement leakages compared to 42 demonstrated by CT and showed overall 95% sensitivity and 100% specificity compared to CT for final post-procedure assessment. Our preliminary results suggest that high-quality RA is reliable and safe as a single technique for PVP guidance, control and post-procedure assessment. It permits fast and cost-effective procedures avoiding multi-modality imaging.

  4. Craniocervical artery dissection: MR imaging and MR angiographic findings

    Oelerich, M.; Schuierer, G.; Stoegbauer, F.; Kurlemann, G.; Schul, C.

    1999-01-01

    Dissection of the carotid and vertebral arteries is a not so uncommon cause of stroke and has to be considered as a differential diagnosis especially in younger patients. Therapeutic and prognostic implications are different from those in extracranial atherosclerotic disease. Dissection results from hemorrhage into the vessel wall usually between the layers of the media. Digital subtraction angiography (DSA) depicts the resulting luminal compromise that may reveal some typical, but not specific, findings. The same is true for non-invasive angiographic techniques such as time-of-flight magnetic resonance angiography (MRA) and computed tomography angiography (CTA), which have shown accurate results compared with DSA. The main advantage of these techniques is the direct visualization of the vessel wall confirming the intramural hematoma. This is achieved best with MR imaging due to the high signal of blood degradation products on T1- and T2-weighted images. Therefore, MRI in combination with MRA is presently the method of choice for initial diagnosis and follow-up of craniocervical artery dissection (CCAD). In some questionable cases, CTA is a non-invasive alternative that is independent of flow phenomena. (orig.)

  5. Craniocervical artery dissection: MR imaging and MR angiographic findings

    Oelerich, M.; Schuierer, G. [Institute of Clinical Radiology, University of Muenster (Germany); Stoegbauer, F. [Department of Neurology, University of Muenster (Germany); Kurlemann, G. [Department of Pediatric Neurology, University of Muenster (Germany); Schul, C. [Department of Neurosurgery, University of Muenster (Germany)

    1999-09-01

    Dissection of the carotid and vertebral arteries is a not so uncommon cause of stroke and has to be considered as a differential diagnosis especially in younger patients. Therapeutic and prognostic implications are different from those in extracranial atherosclerotic disease. Dissection results from hemorrhage into the vessel wall usually between the layers of the media. Digital subtraction angiography (DSA) depicts the resulting luminal compromise that may reveal some typical, but not specific, findings. The same is true for non-invasive angiographic techniques such as time-of-flight magnetic resonance angiography (MRA) and computed tomography angiography (CTA), which have shown accurate results compared with DSA. The main advantage of these techniques is the direct visualization of the vessel wall confirming the intramural hematoma. This is achieved best with MR imaging due to the high signal of blood degradation products on T1- and T2-weighted images. Therefore, MRI in combination with MRA is presently the method of choice for initial diagnosis and follow-up of craniocervical artery dissection (CCAD). In some questionable cases, CTA is a non-invasive alternative that is independent of flow phenomena. (orig.) With 6 figs., 2 tabs., 33 refs.

  6. Pediatric renovascular hypertension in Thailand: CT angiographic findings

    Visrutaratna, Pannee; Srisuwan, Tanop; Sirivanichai, Chusak [Chiang Mai University, Department of Radiology, Faculty of Medicine, Chiang Mai (Thailand)

    2009-12-15

    Renovascular disease is an uncommon but important cause of hypertension in children. When unrecognized and untreated, renovascular hypertension in children can have serious complications. To review the causes of renovascular hypertension and computed tomography angiographic (CTA) findings in children and adolescents. Twenty-eight CTAs from January 2004 to March 2008 of 23 children and adolescents with hypertension were reviewed for the causes and CTA findings. Nine of the 23 children (39%) had abnormal renal arteries with or without abnormal abdominal aortas. Four of these children had Takayasu arteritis, one had moyamoya disease, and one had median arcuate ligament syndrome. One with chronic pyelonephritis had severe stenosis of the proximal right renal artery. The other two children had renal artery stenosis with a nonspecific cause. One child with a normal abdominal aorta and renal arteries had a right suprarenal mass. On pathological examination a ganglioneuroma was found. CTA can help in diagnosis of renovascular hypertension in children and adolescents. Although CTA is not a screening modality, it is appropriate in some situations. (orig.)

  7. Angiographic examinations of the circulatory development of living chick embryos

    Stoeter, P.; Buchhoecker, M.; Bruzek, W.; Drews, U.; Schulze, K.; Tuebingen Univ.; Tuebingen Univ.

    1980-01-01

    In chick embryos of an age of incubation of 5-14 days, the physiological development of the circulation and the morphological differentation of the arterical system were studied by intravital and postmortal angiography. For the examinations of the living embryos, a special radiographic and injection technique had to be developed. The contrast medium was injected into the umbilical veins and transported by the actions of the embryonic heart. Continuous ECG recordings showed no marked interference of the injections with the cardiac activity. According to the angiographic findings, the circulation is relatively fast within the main arteries, but the capillary perfusion is prolonged and lasts up to several minutes. The average circulatory velocity of the blood stream within the carotid artery increases parallel to the arterial enlargement, whereas the circulatory time decreases and the number of heart beats during the period of carotid opacification does not change to a great extent. By this, a steady transport of gas and nutritional material may be achieved in the growing arterial system. (orig.) [de

  8. Pediatric renovascular hypertension in Thailand: CT angiographic findings

    Visrutaratna, Pannee; Srisuwan, Tanop; Sirivanichai, Chusak

    2009-01-01

    Renovascular disease is an uncommon but important cause of hypertension in children. When unrecognized and untreated, renovascular hypertension in children can have serious complications. To review the causes of renovascular hypertension and computed tomography angiographic (CTA) findings in children and adolescents. Twenty-eight CTAs from January 2004 to March 2008 of 23 children and adolescents with hypertension were reviewed for the causes and CTA findings. Nine of the 23 children (39%) had abnormal renal arteries with or without abnormal abdominal aortas. Four of these children had Takayasu arteritis, one had moyamoya disease, and one had median arcuate ligament syndrome. One with chronic pyelonephritis had severe stenosis of the proximal right renal artery. The other two children had renal artery stenosis with a nonspecific cause. One child with a normal abdominal aorta and renal arteries had a right suprarenal mass. On pathological examination a ganglioneuroma was found. CTA can help in diagnosis of renovascular hypertension in children and adolescents. Although CTA is not a screening modality, it is appropriate in some situations. (orig.)

  9. The angiographic findings and interventional treatment of the iatrogenic hemobilia

    Wen feng; Lu Zaiming; Sun Wei; Li Wei; Guo Qiyong

    2012-01-01

    Objective: To evaluate the angiography and interventional embolization in diagnosing and treating the iatrogenic hemobilia. Methods: A total of 21 patients with iatrogenic hemobilia were enrolled in this study. The clinical data were retrospectively analyzed. Percutaneous selective superior mesenteric artery angiography, celiac angiography and common hepatic artery angiography were carried out in all patients. After the bleeding sites were clarified, selective or super-selective catheterization and embolization were performed. The clinical results were analyzed. Results: Active bleeding was confirmed by angiography in all the 21 cases. Angiographic findings included pseudoaneurysm (n=17, 81.0%) and extravasation of contrast medium (n=4, 19.0%). The embolic agents used in this study included polyvinyl alcohol particles (n=2), pure coils (n=8) or Gelfoam particles plus coils (n=11). The success rate of hemostasis after single embolization was 85.7% (18/21), and second embolization procedure had to be carried out in three patients as recurrent massive bleeding occurred in them. All the patients were followed up for 5 to 28 months, and no recurrent hemobilia was observed. No serious complications such as non-targeted vessel embolization, liver function failure, embolization-related infection, etc. occurred. Conclusion: For the treatment of iatrogenic hemobilia, percutaneous selective angiography together with interventional embolization is safe, minimally-invasive, reliable and effective, and this technique should be regarded as the treatment of first choice. (authors)

  10. Intractable epistaxis: which arteries are responsible? An angiographic study.

    de Bonnecaze, Guillaume; Gallois, Y; Chaynes, P; Bonneville, F; Dupret-Bories, A; Chantalat, E; Serrano, E

    2017-11-01

    Epistaxis constitutes a significant proportion of the Otolaryngologist's emergency workload. Optimal management differs in relation to the anatomic origin of the bleeding. The outcome of our study was to determine which artery(ies) could be considered as the cause of severe bleeding in the context of severe epistaxis. Fifty-five procedures of embolization preceded by angiography were reviewed. Medical records of interventionally treated patients were analysed for demographics, medical history, risk factors and clinical data. Angiographic findings were also assessed for active contrast extravasation (blush), vascular abnormality and embolised artery. Previous angiography showed an active contrast extravasation in only 20 procedures. The most common bleeding source was the sphenopalatine artery (SPA) followed by anterior ethmoïdal artery (AEA) and facial artery. Majority of multiple or bilateral extravasations occured in patients with systemic factors. A better understanding of the potential bleeding source might help and limit the risk of treatment failures. Our study confirms that the SPA is the most common cause of severe bleeding. We also emphasise the role of the AEA not only in traumatic context. Others arteries are rarely involved except in patients with comorbidities or frequent recurrences.

  11. Comparative functional scintigraphic and angiographic examination in pancreas diseases

    Mendizov, A.; Brilski, V.; Bozhiyanov, A.; Romanova, A.; Mardzhanov, I.; Glavincheva, I.; Meditsinska Akademiya, Sofia

    1979-01-01

    Pancreas scintigraphy with 75 seleno-methionine, pancreocimine-secretine test and selective abdominal angiography was carried out in patients with chronic pancreatitis, pancreas carcinoma and subjects without any pancreas diseases. Scintigraphic changes in pancreas was found in 95,6 per cent of the patients with chronic pancreatitis (136 patients), in 92 per cent of them with pancreas carcinoma (25 patients) and in 53,4 per cent from the subjects without pancreas diseases (30 examined). Pathological changes in pancreatic secretion was found in 93,4 per cent of the patients with chronic pancreatitis (105 patients), in 93,8 per cent of the subjects with pancreas carcinoma (32 patients) and only in 3,9 per cent from the examined without pancreatic diseases. The angiographic examination is informative mainly in case of tumours and cysts of the pancreas. The diagnostic potentialities of the separate methods for pancreas examination were critically assessed. The basic diagnostic problems in pancreas diseases are solved to a great extent with the combined examination with scintigraphy pancreocimine test and angiography (76 patients). (author)

  12. Angiographic Validation of the American College of Cardiology Foundation–The Society of Thoracic Surgeons Collaboration on the Comparative Effectiveness of Revascularization Strategies Study

    Chakrabarti, Anjan K.; Grau-Sepulveda, Maria V.; O’Brien, Sean; Abueg, Cassandra; Ponirakis, Angelo; Delong, Elizabeth; Peterson, Eric; Klein, Lloyd W.; Garratt, Kirk N.; Weintraub, William S.; Gibson, C. Michael

    2017-01-01

    Background The goal of this study was to compare angiographic interpretation of coronary arteriograms by sites in community practice versus those made by a centralized angiographic core laboratory. Methods and Results The study population consisted of 2013 American College of Cardiology–National Cardiovascular Data Registry (ACC–NCDR) records with 2- and 3- vessel coronary disease from 54 sites in 2004 to 2007. The primary analysis compared Registry (NCDR)-defined 2- and 3-vessel disease versus those from an angiographic core laboratory analysis. Vessel-level kappa coefficients suggested moderate agreement between NCDR and core laboratory analysis, ranging from kappa=0.39 (95% confidence intervals, 0.32–0.45) for the left anterior descending artery to kappa=0.59 (95% confidence intervals, 0.55–0.64) for the right coronary artery. Overall, 6.3% (n=127 out of 2013) of those patients identified with multivessel disease at NCDR sites had had 0- or 1-vessel disease by core laboratory reading. There was no directional bias with regard to overcall, that is, 12.3% of cases read as 3-vessel disease by the sites were read as <3-vessel disease by the core laboratory, and 13.9% of core laboratory 3-vessel cases were read as <3-vessel by the sites. For a subset of patients with left main coronary disease, registry overcall was not linked to increased rates of mortality or myocardial infarction. Conclusions There was only modest agreement between angiographic readings in clinical practice and those from an independent core laboratory. Further study will be needed because the implications for patient management are uncertain. PMID:24496239

  13. Angiographic validation of the American College of Cardiology Foundation-the Society of Thoracic Surgeons Collaboration on the Comparative Effectiveness of Revascularization Strategies study.

    Chakrabarti, Anjan K; Grau-Sepulveda, Maria V; O'Brien, Sean; Abueg, Cassandra; Ponirakis, Angelo; Delong, Elizabeth; Peterson, Eric; Klein, Lloyd W; Garratt, Kirk N; Weintraub, William S; Gibson, C Michael

    2014-02-01

    The goal of this study was to compare angiographic interpretation of coronary arteriograms by sites in community practice versus those made by a centralized angiographic core laboratory. The study population consisted of 2013 American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) records with 2- and 3- vessel coronary disease from 54 sites in 2004 to 2007. The primary analysis compared Registry (NCDR)-defined 2- and 3-vessel disease versus those from an angiographic core laboratory analysis. Vessel-level kappa coefficients suggested moderate agreement between NCDR and core laboratory analysis, ranging from kappa=0.39 (95% confidence intervals, 0.32-0.45) for the left anterior descending artery to kappa=0.59 (95% confidence intervals, 0.55-0.64) for the right coronary artery. Overall, 6.3% (n=127 out of 2013) of those patients identified with multivessel disease at NCDR sites had had 0- or 1-vessel disease by core laboratory reading. There was no directional bias with regard to overcall, that is, 12.3% of cases read as 3-vessel disease by the sites were read as <3-vessel disease by the core laboratory, and 13.9% of core laboratory 3-vessel cases were read as <3-vessel by the sites. For a subset of patients with left main coronary disease, registry overcall was not linked to increased rates of mortality or myocardial infarction. There was only modest agreement between angiographic readings in clinical practice and those from an independent core laboratory. Further study will be needed because the implications for patient management are uncertain.

  14. Rapid and accurate identification of isolates of Candida species by melting peak and melting curve analysis of the internally transcribed spacer region 2 fragment (ITS2-MCA)

    Decat, E.; van Mechelen, E.; Saerens, B.; Vermeulen, S.J.T.; Boekhout, T.; de Blaiser, S.; Vaneechoutte, M.; Deschaght, P.

    2013-01-01

    Rapid identification of clinically important yeasts can facilitate the initiation of anti-fungal therapy, since susceptibility is largely species-dependent. We evaluated melting peak and melting curve analysis of the internally transcribed spacer region 2 fragment (ITS2-MCA) as an identification

  15. Vertical Root Fracture initiation in curved roots after root canal preparation: A dentinal micro-crack analysis with LED transillumination.

    Miguéns-Vila, Ramón; Martín-Biedma, Benjamín; Varela-Patiño, Purificación; Ruíz-Piñón, Manuel; Castelo-Baz, Pablo

    2017-10-01

    One of the causative factors of root defects is the increased friction produced by rotary instrumentation. A high canal curvature may increase stress, making the tooth more susceptible to dentinal cracks. The purpose of this study was to evaluate dentinal micro-crack formation with the ProTaper NEXT and ProTaper Universal systems using LED transillumination, and to analyze the micro-crack generated at the point of maximum canal curvature. 60 human mandibular premolars with curvatures between 30-49° and radii between 2-4 mm were used. The root canals were instrumented using the Protaper Universal® and Protaper NEXT® systems, with the aid of the Proglider® system. The obtained samples were sectioned transversely before subsequent analysis with LED transillumination at 2 mm and 8 mm from the apex and at the point of maximum canal curvature. Defects were scored: 0 for no defects; and 1 for micro-cracks. Root defects were not observed in the control group. The ProTaper NEXT system caused fewer defects (16.7%) than the ProTaper Universal system (40%) ( P Universal system caused significantly more micro-cracks at the point of maximum canal curvature than the ProTaper NEXT system ( P Universal system. A higher prevalence of defects was found at the point of maximum curvature in the ProTaper Universal group. Key words: Curved root, Micro-crack, point of maximum canal curvature, ProTaper NEXT, ProTaper Universal, Vertical root fracture.

  16. Miltenberger blood group typing by real-time polymerase chain reaction (qPCR) melting curve analysis in Thai population.

    Vongsakulyanon, A; Kitpoka, P; Kunakorn, M; Srikhirin, T

    2015-12-01

    To develop reliable and convenient methods for Miltenberger (Mi(a) ) blood group typing. To apply real-time polymerase chain reaction (qPCR) melting curve analysis to Mi(a) blood group typing. The Mi(a) blood group is the collective set of glycophorin hybrids in the MNS blood group system. Mi(a+) blood is common among East Asians and is also found in the Thai population. Incompatible Mi(a) blood transfusions pose the risk of life-threatening haemolysis; therefore, Mi(a) blood group typing is necessary in ethnicities where the Mi(a) blood group is prevalent. One hundred and forty-three blood samples from Thai blood donors were used in the study. The samples included 50 Mi(a+) samples and 93 Mi(a-) samples, which were defined by serology. The samples were typed by Mi(a) typing qPCR, and 50 Mi(a+) samples were sequenced to identify the Mi(a) subtypes. Mi(a) subtyping qPCR was performed to define GP.Mur. Both Mi(a) typing and Mi(a) subtyping were tested on a conventional PCR platform. The results of Mi(a) typing qPCR were all concordant with serology. Sequencing of the 50 Mi(a+) samples revealed 47 GP.Mur samples and 3 GP.Hop or Bun samples. Mi(a) subtyping qPCR was the supplementary test used to further define GP.Mur from other Mi(a) subtypes. Both Mi(a) typing and Mi(a) subtyping performed well using a conventional PCR platform. Mi(a) typing qPCR correctly identified Mi(a) blood groups in a Thai population with the feasibility of Mi(a) subtype discrimination, and Mi(a) subtyping qPCR was able to further define GP.Mur from other Mi(a) subtypes. © 2015 British Blood Transfusion Society.

  17. Applying CFD in the Analysis of Heavy-Oil Transportation in Curved Pipes Using Core-Flow Technique

    S Conceição

    2017-06-01

    Full Text Available Multiphase flow of oil, gas and water occurs in the petroleum industry from the reservoir to the processing units. The occurrence of heavy oils in the world is increasing significantly and points to the need for greater investment in the reservoirs exploitation and, consequently, to the development of new technologies for the production and transport of this oil. Therefore, it is interesting improve techniques to ensure an increase in energy efficiency in the transport of this oil. The core-flow technique is one of the most advantageous methods of lifting and transporting of oil. The core-flow technique does not alter the oil viscosity, but change the flow pattern and thus, reducing friction during heavy oil transportation. This flow pattern is characterized by a fine water pellicle that is formed close to the inner wall of the pipe, aging as lubricant of the oil flowing in the core of the pipe. In this sense, the objective of this paper is to study the isothermal flow of heavy oil in curved pipelines, employing the core-flow technique. A three-dimensional, transient and isothermal mathematical model that considers the mixture and k-e  turbulence models to address the gas-water-heavy oil three-phase flow in the pipe was applied for analysis. Simulations with different flow patterns of the involved phases (oil-gas-water have been done, in order to optimize the transport of heavy oils. Results of pressure and volumetric fraction distribution of the involved phases are presented and analyzed. It was verified that the oil core lubricated by a fine water layer flowing in the pipe considerably decreases pressure drop.

  18. Angiographically borderline left main coronary artery lesions: correlation of transthoracic doppler echocardiography and intravascular ultrasound: a pilot study

    Varga Albert

    2011-06-01

    Full Text Available Abstract Background the clinical decision making could be difficult in patients with borderline lesions (visually assessed stenosis severity of 30 to 50% of the left main coronary artery (LM. The aim of the study was to evaluate the relationship between transthoracic Doppler (TTDE peak diastolic flow velocity (PDV and intravascular ultrasound (IVUS measurements in the assessment of angiographically borderline LM lesions. Methods 27 patients (mean age 64 ± 8 years, 21 males with borderline LM stenosis referred for IVUS examination were included in the study. We performed standard IVUS with minimal lumen area (MLA and plaque burden (PB measurement and routine quantitative coronary angiography (QCA with diameter stenosis (%DS and area stenosis (%AS assessment in all. During TTDE, resting PDV was measured in the LM. Results interpretable Doppler signal could be obtained in 24 patients (88% feasibility; therefore these patients entered the final analysis. MLA was 7.1 ± 2.7 mm2. TTDE measured PDV correlated significantly with IVUS-derived MLA (r = -0.46, p 2 LM stenosis. Conclusion In angiographically borderline LM disease, resting PDV from transthoracic echocardiography is increased in presence of increased plaque burden by IVUS. TTDE evaluation might be a useful adjunct to other invasive and non-invasive methods in the assessment of borderline LM lesions. Further, large scale studies are needed to establish the exact cut-off value of PDV for routine clinical application.

  19. On the analysis of glow curves with the general order kinetics: Reliability of the computed trap parameters

    Ortega, F. [Facultad de Ingeniería (UNCPBA) and CIFICEN (UNCPBA – CICPBA – CONICET), Av. del Valle 5737, 7400 Olavarría (Argentina); Santiago, M.; Martinez, N.; Marcazzó, J.; Molina, P.; Caselli, E. [Instituto de Física Arroyo Seco (UNCPBA) and CIFICEN (UNCPBA – CICPBA – CONICET), Pinto 399, 7000 Tandil (Argentina)

    2017-04-15

    Nowadays the most employed kinetics for analyzing glow curves is the general order kinetics (GO) proposed by C. E. May and J. A. Partridge. As shown in many articles this kinetics might yield wrong parameters characterizing trap and recombination centers. In this article this kinetics is compared with the modified general order kinetics put forward by M. S. Rasheedy by analyzing synthetic glow curves. The results show that the modified kinetics gives parameters, which are more accurate than that yield by the original general order kinetics. A criterion is reported to evaluate the accuracy of the trap parameters found by deconvolving glow curves. This criterion was employed to assess the reliability of the trap parameters of the YVO{sub 4}: Eu{sup 3+} compounds.

  20. The hyperbolic chemical bond: Fourier analysis of ground and first excited state potential energy curves of HX (X = H-Ne).

    Harrison, John A

    2008-09-04

    RHF/aug-cc-pVnZ, UHF/aug-cc-pVnZ, and QCISD/aug-cc-pVnZ, n = 2-5, potential energy curves of H2 X (1) summation g (+) are analyzed by Fourier transform methods after transformation to a new coordinate system via an inverse hyperbolic cosine coordinate mapping. The Fourier frequency domain spectra are interpreted in terms of underlying mathematical behavior giving rise to distinctive features. There is a clear difference between the underlying mathematical nature of the potential energy curves calculated at the HF and full-CI levels. The method is particularly suited to the analysis of potential energy curves obtained at the highest levels of theory because the Fourier spectra are observed to be of a compact nature, with the envelope of the Fourier frequency coefficients decaying in magnitude in an exponential manner. The finite number of Fourier coefficients required to describe the CI curves allows for an optimum sampling strategy to be developed, corresponding to that required for exponential and geometric convergence. The underlying random numerical noise due to the finite convergence criterion is also a clearly identifiable feature in the Fourier spectrum. The methodology is applied to the analysis of MRCI potential energy curves for the ground and first excited states of HX (X = H-Ne). All potential energy curves exhibit structure in the Fourier spectrum consistent with the existence of resonances. The compact nature of the Fourier spectra following the inverse hyperbolic cosine coordinate mapping is highly suggestive that there is some advantage in viewing the chemical bond as having an underlying hyperbolic nature.

  1. Discrimination of Closely-Spaced Geosynchronous Satellites - Phase Curve Analysis & New Small Business Innovative Research (SBIR) Efforts

    Levan, P.

    2010-09-01

    Geosynchronous objects appear as unresolved blurs even when observed with the largest ground-based telescopes. Due to the lack of any spatial detail, two or more objects appearing at similar brightness levels within the spectral bandpass they are observed are difficult to distinguish. Observing a changing pattern of such objects from one time epoch to another showcases the deficiencies in associating individual objects before and after the configuration change. This paper explores solutions to this deficiency in the form of spectral (under small business innovative research) and phase curve analyses. The extension of the technique to phase curves proves to be a powerful new capability.

  2. Lagrangian Curves on Spectral Curves of Monopoles

    Guilfoyle, Brendan; Khalid, Madeeha; Ramon Mari, Jose J.

    2010-01-01

    We study Lagrangian points on smooth holomorphic curves in TP 1 equipped with a natural neutral Kaehler structure, and prove that they must form real curves. By virtue of the identification of TP 1 with the space LE 3 of oriented affine lines in Euclidean 3-space, these Lagrangian curves give rise to ruled surfaces in E 3 , which we prove have zero Gauss curvature. Each ruled surface is shown to be the tangent lines to a curve in E 3 , called the edge of regression of the ruled surface. We give an alternative characterization of these curves as the points in E 3 where the number of oriented lines in the complex curve Σ that pass through the point is less than the degree of Σ. We then apply these results to the spectral curves of certain monopoles and construct the ruled surfaces and edges of regression generated by the Lagrangian curves.

  3. Angiographic classification of patent ductus arteriosus and its clinical implications

    Qingqiao, Zhang; Shiliang, Jiang; Lianjun, Huang; Shihua, Zhao; Jian, Ling; Zhongying, Xu; Hong, Zheng; Ruolan, Xie; Ruping, Dai [Chinese Academy of Medical Sciences and Beijing Union Medical College, Beijing (China). Cardiovascular Inst. and Fuwai Hospital, Dept. of Radiology

    2004-04-01

    Objective: To study the angiographic appearance of patent ductus arteriosus (PDA) and provide information for clinical treatment. Methods: Between July 1994 and October 2002, 483 patients (142 male, 341 female) with isolated PDA underwent aortography before attempted transcatheter closure of PDA, the mean age was (14.6 {+-} 11.4) years (range 0.8 to 63 years). Left lateral aortography was performed in 482 patients. Among them, additional aortography in right anterior oblique 30 degree - 50 degree or left anterior oblique 60 degree - 80 degree (or plus caudal 20 degree) projection was performed in 6 and 4 patients, respectively. One patient with mirror-image dextrocardia underwent aortography in right lateral projection. Results: The configuration of PDA was classified into six types. Four hundred and twenty (87%) patients had funnel shape PDA, the mean minimum diameter of PDA was 4.2 {+-} 1.6 mm (range 1 to 15 mm). Three (0.6%) patients had window shape PDA, the diameters of PDA were 8.0 mm, 9.0 mm, and 9.0 mm, respectively. Thirty four (7.0%) patients had tubular shape PDA, the mean diameter of PDA was (5.4 {+-} 3.8) mm (range 0.8 to 20 mm). Eleven (2.3%) patients had rosary shape PDA, the mean minimum diameter of PDA was (2.1 {+-} 0.5) mm (range 1.0 to 3.7 mm). Ten (2.1%) patients had finger shape PDA, the mean minimum diameter of PDA was (1.5 {+-} 0.4) mm (range 1.0 to 3.0 mm). Five (1.0%) patients had irregular shape PDA, the minimum diameters of PDA were 1.2, 2.1, 3.2, 4.0, and 6.0 mm, respectively. Conclusion: The morphology of PDA varied considerably, and the awareness of these variations is helpful for clinical treatment.

  4. Angiographic classification of patent ductus arteriosus and its clinical implications

    Zhang Qingqiao; Jiang Shiliang; Huang Lianjun; Zhao Shihua; Ling Jian; Xu Zhongying; Zheng Hong; Xie Ruolan; Dai Ruping

    2004-01-01

    Objective: To study the angiographic appearance of patent ductus arteriosus (PDA) and provide information for clinical treatment. Methods: Between July 1994 and October 2002, 483 patients (142 male, 341 female) with isolated PDA underwent aortography before attempted transcatheter closure of PDA, the mean age was (14.6 ± 11.4) years (range 0.8 to 63 years). Left lateral aortography was performed in 482 patients. Among them, additional aortography in right anterior oblique 30 degree - 50 degree or left anterior oblique 60 degree - 80 degree (or plus caudal 20 degree) projection was performed in 6 and 4 patients, respectively. One patient with mirror-image dextrocardia underwent aortography in right lateral projection. Results: The configuration of PDA was classified into six types. Four hundred and twenty (87%) patients had funnel shape PDA, the mean minimum diameter of PDA was 4.2 ± 1.6 mm (range 1 to 15 mm). Three (0.6%) patients had window shape PDA, the diameters of PDA were 8.0 mm, 9.0 mm, and 9.0 mm, respectively. Thirty four (7.0%) patients had tubular shape PDA, the mean diameter of PDA was (5.4 ± 3.8) mm (range 0.8 to 20 mm). Eleven (2.3%) patients had rosary shape PDA, the mean minimum diameter of PDA was (2.1 ± 0.5) mm (range 1.0 to 3.7 mm). Ten (2.1%) patients had finger shape PDA, the mean minimum diameter of PDA was (1.5 ± 0.4) mm (range 1.0 to 3.0 mm). Five (1.0%) patients had irregular shape PDA, the minimum diameters of PDA were 1.2, 2.1, 3.2, 4.0, and 6.0 mm, respectively. Conclusion: The morphology of PDA varied considerably, and the awareness of these variations is helpful for clinical treatment

  5. Long-term clinical and angiographic results of Sirolimus-Eluting Stent in Complex Coronary Chronic Total Occlusion Revascularization: the SECTOR registry.

    Galassi, Alfredo R; Tomasello, Salvatore D; Costanzo, Luca; Campisano, Maria B; Barrano, Giombattista; Tamburino, Corrado

    2011-10-01

    Drug-eluting stents showed a better angiographic and clinical outcome in comparison with bare metal stent in chronic total occlusions (CTOs) percutaneous revascularization, however, great concerns still remain regarding the rate of restenosis and reocclusion in comparison with nonocclusive lesions. To evaluate angiographic and clinical outcomes after sirolimus-eluting stent (SES) implantation in the setting of a "real world" series of complex CTOs. From January 2006 to December 2008, 172 consecutive patients with 179 CTO lesions were enrolled into registry. Among these, successful recanalization was obtained in 144 lesions (80.4%) with exclusive SES implantation in 104 lesions. The 9-12 months angiographic follow-up was executed in 85.5% of lesions with evidence of angiographic binary restenosis in 16.8% of lesions. Total stent length and number of stent implanted were recognized as independent predictors of restenosis (odds ratio [OR] 4.7, 95% confidence interval [CI] 1.28-107.09, P = 0.02) and (OR 5.8, 95% CI 1.39-23.55, P = 0.01), respectively.The 2-year clinical follow-up showed rates of target lesion revascularization, non-Q wave myocardial infarction, and total major adverse cardiovascular events (MACEs) of 11.1%, 2%, and 13.1%, respectively. Cox proportional-hazard analysis showed diabetes as independent predictor of MACEs (hazard ratio [HR] 4.832; 95% CI, 0.730-0.861; P = 0.028). Data from this registry demonstrate the long-term efficacy and safety of SES implantation after complex CTOs recanalization. ©2011, Wiley Periodicals, Inc.

  6. Application of risk curve for statistical analysis of backside corrosion in the bottom floors of oil storage tanks

    Kasai, Naoya; Maeda, Takuma; Tamura, Koichi; Kitsukawa, Shigeo; Sekine, Kazuyoshi

    2016-01-01

    Overall thickness profile data for backside corrosion of the bottom floors of 17 oil storage tanks were collected, and a risk curve from the overall thickness profile and discrete thickness data was derived to evaluate the corrosion risk of the bottom floors. The slope of the risk curve in the large corrosion region was found to indicate the local corrosion condition. Parameters for evaluating localized corrosion derived from the corrosion distributions were also investigated to evaluate the corrosion risk of the bottom floors. Compared with the parameters obtained using the overall thickness profile and discrete thickness data, the slope of the risk curve is an excellent evaluation parameter using discrete thickness data. Thus, it is possible to accurately evaluate the corrosion characteristics of the bottom floors of oil storage tanks with the parameters obtained from discrete thickness data. - Highlights: • The risk curves for corrosion show the corrosion characteristic. • The obtained parameters indicate the corrosion characteristic. • The corrosion characteristic can be evaluated with discrete thickness data.

  7. Analysis of the glow curve of SrB 4O 7:Dy compounds employing the GOT model

    Ortega, F.; Molina, P.; Santiago, M.; Spano, F.; Lester, M.; Caselli, E.

    2006-02-01

    The glow curve of SrB 4O 7:Dy phosphors has been analysed with the general one trap model (GOT). To solve the differential equation describing the GOT model a novel algorithm has been employed, which reduces significantly the deconvolution time with respect to the time required by usual integration algorithms, such as the Runge-Kutta method.

  8. Analysis of the glow curve of SrB4O7:Dy compounds employing the GOT model

    Ortega, F.; Molina, P.; Santiago, M.; Spano, F.; Lester, M.; Caselli, E.

    2006-01-01

    The glow curve of SrB 4 O 7 :Dy phosphors has been analysed with the general one trap model (GOT). To solve the differential equation describing the GOT model a novel algorithm has been employed, which reduces significantly the deconvolution time with respect to the time required by usual integration algorithms, such as the Runge-Kutta method

  9. Comparative analysis of the apparent saturation hysteresis approach and the domain theory of hysteresis in respect of prediction of scanning curves and air entrapment

    Beriozkin, A.; Mualem, Y.

    2018-05-01

    This study theoretically analyzes the concept of apparent saturation hysteresis, combined with the Scott et al. (1983) scaling approach, as suggested by Parker and Lenhard (1987), to account for the effect of air entrapment and release on the soil water hysteresis. We found that the theory of Parker and Lenhard (1987) is comprised of some mutually canceling mathematical operations, and when cleared of the superfluous intermediate calculations, their model reduces to the original Scott et al.'s (1983) scaling method, supplemented with the requirement of closure of scanning loops. Our analysis reveals that actually there is no effect of their technique of accounting for the entrapped air on the final prediction of the effective saturation (or water content) scanning curves. Our consideration indicates that the use of the Land (1968) formula for assessing the amount of entrapped air is in disaccord with the apparent saturation concept as introduced by Parker and Lenhard (1987). In this paper, a proper routine is suggested for predicting hysteretic scanning curves of any order, given the two measured main curves, in the complete hysteretic domain and some verification tests are carried out versus measured results. Accordingly, explicit closed-form formulae for direct prediction (with no need of intermediate calculation) of scanning curves up to the third order are derived to sustain our analysis.

  10. Evaluating Design Parameters for Breakthrough Curve Analysis and Kinetics of Fixed Bed Columns for Cu(II Cations Using Lignocellulosic Wastes

    Zaira Zaman Chowdhury

    2014-12-01

    Full Text Available A continuous adsorption study for removal of Cu(II cations from wastewater using a fixed-bed column was conducted. A granular carbonaceous activated adsorbent produced by carbonization of the outer rind, or exocarp, of mangostene fruit shell was used for column packing. The effects of feed flow rate, influent cation concentration, and bed depth on the breakthrough curve were investigated at pH 5.5. Experimental analysis confirmed that the breakthrough curves were dependent on flow rate, initial concentration of Cu(II cations, and bed height related to the amount of activated carbon used for column packing. Thomas, Yoon–Nelson, and Adams–Bohart models were applied to analyze the breakthrough curves at different conditions. Linear regression analysis of experimental data demonstrated that Thomas and Yoon–Nelson models were appropriate to explain the breakthrough curve, while the Adams–Bohart model was only applicable to predict the initial part of the dynamic process. It was concluded that the column packed with fruit rind based activated carbon can be used to treat Cu(II-enriched wastewater.

  11. Quantitative analysis of the hydration of lithium salts in water using multivariate curve resolution of near-infrared spectra

    Barba, M. Isabel [Group of Research in Applied Thermal Engineering-CREVER, Mechanical Engineering Dept. (Spain); Larrechi, M. Soledad, E-mail: mariasoledad.larrechi@urv.cat [Analytical and Organic Chemistry Dept., Universitat Rovira i Virgili, Tarragona (Spain); Coronas, Alberto [Group of Research in Applied Thermal Engineering-CREVER, Mechanical Engineering Dept. (Spain)

    2016-05-05

    The hydration process of lithium iodide, lithium bromide, lithium chloride and lithium nitrate in water was analyzed quantitatively by applying multivariate curve resolution alternating least squares (MCR-ALS) to their near infrared spectra recorded between 850 nm and 1100 nm. The experiments were carried out using solutions with a salt mass fraction between 0% and 72% for lithium bromide, between 0% and 67% for lithium nitrate and between 0% and 62% for lithium chloride and lithium iodide at 323.15 K, 333.15 K, 343.15 K and 353.15 K, respectively. Three factors were determined for lithium bromide and lithium iodide and two factors for the lithium chloride and lithium nitrate by singular value decomposition (SVD) of their spectral data matrices. These factors are associated with various chemical environments in which there are aqueous clusters containing the ions of the salts and non-coordinated water molecules. Spectra and concentration profiles of non-coordinated water and cluster aqueous were retrieved by MCR-ALS. The amount of water involved in the process of hydration of the various salts was quantified. The results show that the water absorption capacity increases in the following order LiI < LiBr < LiNO{sub 3} < LiCl. The salt concentration at which there is no free water in the medium was calculated at each one of the temperatures considered. The values ranged between 62.6 and 65.1% for LiBr, 45.5–48.3% for LiCl, 60.4–61.2% for LiI and 60.3–63.7% for LiNO{sub 3}. These values are an initial approach to determining the concentration as from which crystal formation is favored. - Highlights: • Quantitative analysis of the hydration of lithium salts in water. • The absorption capacity of the electrolytes in function of the salt is evaluated. • The lithium salt concentration is estimated when the crystal formation is favored.

  12. Quantitative analysis of the hydration of lithium salts in water using multivariate curve resolution of near-infrared spectra

    Barba, M. Isabel; Larrechi, M. Soledad; Coronas, Alberto

    2016-01-01

    The hydration process of lithium iodide, lithium bromide, lithium chloride and lithium nitrate in water was analyzed quantitatively by applying multivariate curve resolution alternating least squares (MCR-ALS) to their near infrared spectra recorded between 850 nm and 1100 nm. The experiments were carried out using solutions with a salt mass fraction between 0% and 72% for lithium bromide, between 0% and 67% for lithium nitrate and between 0% and 62% for lithium chloride and lithium iodide at 323.15 K, 333.15 K, 343.15 K and 353.15 K, respectively. Three factors were determined for lithium bromide and lithium iodide and two factors for the lithium chloride and lithium nitrate by singular value decomposition (SVD) of their spectral data matrices. These factors are associated with various chemical environments in which there are aqueous clusters containing the ions of the salts and non-coordinated water molecules. Spectra and concentration profiles of non-coordinated water and cluster aqueous were retrieved by MCR-ALS. The amount of water involved in the process of hydration of the various salts was quantified. The results show that the water absorption capacity increases in the following order LiI < LiBr < LiNO_3 < LiCl. The salt concentration at which there is no free water in the medium was calculated at each one of the temperatures considered. The values ranged between 62.6 and 65.1% for LiBr, 45.5–48.3% for LiCl, 60.4–61.2% for LiI and 60.3–63.7% for LiNO_3. These values are an initial approach to determining the concentration as from which crystal formation is favored. - Highlights: • Quantitative analysis of the hydration of lithium salts in water. • The absorption capacity of the electrolytes in function of the salt is evaluated. • The lithium salt concentration is estimated when the crystal formation is favored.

  13. A regret theory approach to decision curve analysis: a novel method for eliciting decision makers' preferences and decision-making.

    Tsalatsanis, Athanasios; Hozo, Iztok; Vickers, Andrew; Djulbegovic, Benjamin

    2010-09-16

    Decision curve analysis (DCA) has been proposed as an alternative method for evaluation of diagnostic tests, prediction models, and molecular markers. However, DCA is based on expected utility theory, which has been routinely violated by decision makers. Decision-making is governed by intuition (system 1), and analytical, deliberative process (system 2), thus, rational decision-making should reflect both formal principles of rationality and intuition about good decisions. We use the cognitive emotion of regret to serve as a link between systems 1 and 2 and to reformulate DCA. First, we analysed a classic decision tree describing three decision alternatives: treat, do not treat, and treat or no treat based on a predictive model. We then computed the expected regret for each of these alternatives as the difference between the utility of the action taken and the utility of the action that, in retrospect, should have been taken. For any pair of strategies, we measure the difference in net expected regret. Finally, we employ the concept of acceptable regret to identify the circumstances under which a potentially wrong strategy is tolerable to a decision-maker. We developed a novel dual visual analog scale to describe the relationship between regret associated with "omissions" (e.g. failure to treat) vs. "commissions" (e.g. treating unnecessary) and decision maker's preferences as expressed in terms of threshold probability. We then proved that the Net Expected Regret Difference, first presented in this paper, is equivalent to net benefits as described in the original DCA. Based on the concept of acceptable regret we identified the circumstances under which a decision maker tolerates a potentially wrong decision and expressed it in terms of probability of disease. We present a novel method for eliciting decision maker's preferences and an alternative derivation of DCA based on regret theory. Our approach may be intuitively more appealing to a decision-maker, particularly

  14. A regret theory approach to decision curve analysis: A novel method for eliciting decision makers' preferences and decision-making

    Vickers Andrew

    2010-09-01

    Full Text Available Abstract Background Decision curve analysis (DCA has been proposed as an alternative method for evaluation of diagnostic tests, prediction models, and molecular markers. However, DCA is based on expected utility theory, which has been routinely violated by decision makers. Decision-making is governed by intuition (system 1, and analytical, deliberative process (system 2, thus, rational decision-making should reflect both formal principles of rationality and intuition about good decisions. We use the cognitive emotion of regret to serve as a link between systems 1 and 2 and to reformulate DCA. Methods First, we analysed a classic decision tree describing three decision alternatives: treat, do not treat, and treat or no treat based on a predictive model. We then computed the expected regret for each of these alternatives as the difference between the utility of the action taken and the utility of the action that, in retrospect, should have been taken. For any pair of strategies, we measure the difference in net expected regret. Finally, we employ the concept of acceptable regret to identify the circumstances under which a potentially wrong strategy is tolerable to a decision-maker. Results We developed a novel dual visual analog scale to describe the relationship between regret associated with "omissions" (e.g. failure to treat vs. "commissions" (e.g. treating unnecessary and decision maker's preferences as expressed in terms of threshold probability. We then proved that the Net Expected Regret Difference, first presented in this paper, is equivalent to net benefits as described in the original DCA. Based on the concept of acceptable regret we identified the circumstances under which a decision maker tolerates a potentially wrong decision and expressed it in terms of probability of disease. Conclusions We present a novel method for eliciting decision maker's preferences and an alternative derivation of DCA based on regret theory. Our approach may

  15. Transarterial embolization in the management of intractable epistaxis: the angiographic findings and results based on etiologies.

    Wang, Bin; Zu, Qing-Quan; Liu, Xing-Long; Zhou, Chun-Gao; Xia, Jin-Guo; Zhao, Lin-Bo; Shi, Hai-Bin; Liu, Sheng

    2016-08-01

    Transarterial embolization (TAE) appears to be a safe and effective treatment for patients with intractable epistaxis, despite different etiologies or angiography findings. Idiopathic epistaxis is prone to present with negative angiographic findings. To retrospectively evaluate the safety and effectiveness of TAE for intractable epistaxis, and focus on the factors of etiology and angiographic findings. From March 2008 to December 2014, the data of 43 patients with intractable bleeding undergoing TAE were reviewed. The outcomes of interventional therapy were assessed according to different etiology (malignant or benign disease) and angiographic finding (positive or negative angiogram). Positive angiographic findings were found in 11 of 12 cases with malignant diseases and 22 of 31 cases with benign diseases, respectively (p = 0.237). Among the 10 cases with negative angiographic findings, the negative angiography rate of idiopathic epistaxis was higher than that of epistaxis with definite etiology (p = 0.003). Bleeding was controlled successfully in all of the 43 patients after embolization. During the mean follow-up period of 24.0 ± 16.7 months, five patients relapsed. No significant difference was found in recurrence rates between malignant and benign diseases or between positive and negative angiography (p = 0.241, p = 0.704, respectively).

  16. Coronary artery ectasia, its clinical profile and angiographic characteristics, single centre experience

    Ahmed, N.; Mohyudin, M.T.; Saad, A.A.; Iqbal, M.M.

    2013-01-01

    Objective: To evaluate the incidence of coronary ectasia and its, its clinical profile and angiographic characteristics in our population. Methods: A retrospective analysis was conducted on all coronary angiograms performed at the catheterization laboratory of Ch. Pervaiz Elahi Institute of Cardiology, Multan between the period of January 2011 and December 2012. Data were collected from catheterization films, and medical records. Results: In a total of 6540 coronary angiograms were performed during the period of the study. A total of 225 (3.44%) angiograms showed coronary ectasia of both mixed and pure types. Pure ectasia with no coronary obstructive lesions was seen in 58 (25.77%). Type 4 was most common 95 pts. (42.22%), as per the Markis classification. Right coronary artery (RCA) was the most commonly affected vessel 162 (72%) followed by left anterior descending artery (LAD) 76 (33.78%) and 38 patients (16.88%) patients had circumflex artery involvement. 132 patients (58.66%) had good left ventricular (LV) systolic function. Conclusion: Prevalence of Coronary ectasia in the population presenting to Ch. Pervaiz Elahi Institute of Cardiology, Multan during the study period was 3.4%. Majority of patients were males, associated with, hypertension and diabetes mellitus. CAE was associated with obstructive coronary artery disease in about 74.22% of cases. RCA was the most commonly affected vessel. (author)

  17. High-Resolution CT and Angiographic Evaluation of NexStent Wall Adaptation

    Nemes, Balazs; Lukacs, Levente; Balazs, Gyoergy; Dosa, Edit; Berczi, Viktor; Huettl, Kalman

    2009-01-01

    Carotid stenting is a minimally invasive treatment for extracranial carotid artery stenosis. Stent design may affect technical success and complications in a certain subgroup of patients. We examined the wall adaptability of a new closed-cell carotid stent (NexStent), which has a unique rolled sheet design. Forty-one patients had 42 carotid arteries treated with angioplasty and stenting for internal carotid artery stenosis. The mean patient age was 65 ± 10 years. All patients underwent high-resolution computed tomographic angiography after the stent implantation. Data analysis included pre- and postprocedural stenosis, procedure complications, plaque calcification, and stent apposition. We reviewed the angiographic and computed tomographic images for plaque coverage and stent expansion. All procedures were technically successful. Mean stenosis was reduced from 84 ± 8% before the procedure to 15.7 ± 7% after stenting. Two patients experienced transient ischemic attack; one patient had bradycardia and hypotension. Stent induced kinking was observed in one case. Good plaque coverage and proper overlapping of the rolled sheet was achieved in all cases. There was weak correlation between the residual stenosis and the amount of calcification. The stent provides adequate expansion and adaptation to the tapering anatomy of the bifurcation.

  18. Transforaminal Lumbar Interbody Fusion with Rigid Interspinous Process Fixation: A Learning Curve Analysis of a Surgeon Team's First 74 Cases.

    Doherty, Patrick; Welch, Arthur; Tharpe, Jason; Moore, Camille; Ferry, Chris

    2017-05-30

    Studies have shown that a significant learning curve may be associated with adopting minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) with bilateral pedicle screw fixation (BPSF). Accordingly, several hybrid TLIF techniques have been proposed as surrogates to the accepted BPSF technique, asserting that less/fewer fixation(s) or less disruptive fixation may decrease the learning curve while still maintaining the minimally disruptive benefits. TLIF with interspinous process fixation (ISPF) is one such surrogate procedure. However, despite perceived ease of adaptability given the favorable proximity of the spinous processes, no evidence exists demonstrating whether or not the technique may possess its own inherent learning curve. The purpose of this study was to determine whether an intraoperative learning curve for one- and two-level TLIF + ISPF may exist for a single lead surgeon. Seventy-four consecutive patients who received one- or two-Level TLIF with rigid ISPF by a single lead surgeon were retrospectively reviewed. It was the first TLIF + ISPF case series for the lead surgeon. Intraoperative blood loss (EBL), hospitalization length-of-stay (LOS), fluoroscopy time, and postoperative complications were collected. EBL, LOS, and fluoroscopy time were modeled as a function of case number using multiple linear regression methods. A change point was included in each model to allow the trajectory of the outcomes to change during the duration of the case series. These change points were determined using profile likelihood methods. Models were fit using the maximum likelihood estimates for the change points. Age, sex, body mass index (BMI), and the number of treated levels were included as covariates. EBL, LOS, and fluoroscopy time did not significantly differ by age, sex, or BMI (p ≥ 0.12). Only EBL differed significantly by the number of levels (p = 0.026). The case number was not a significant predictor of EBL, LOS, or fluoroscopy time (p ≥ 0

  19. Comparison of a Simple Angiographic Approach With a Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery Score-Based Approach for Left Main Coronary Artery Stenting: A Pooled Analysis of Serial PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease) Studies.

    Lee, Pil Hyung; Lee, Jong-Young; Lee, Cheol Whan; Kim, Seon-Ok; Ahn, Jung-Min; Park, Duk-Woo; Kang, Soo-Jin; Lee, Seung-Whan; Kim, Young-Hak; Park, Seong-Wook; Park, Seung-Jung

    2018-01-01

    The applicability of Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery scores to left main coronary artery disease (CAD) has been questioned. A simplified alternative is needed for guiding decision making. We evaluated the prognostic value of a simplified angiographic classification in comparison with a Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery score-based approach for patients with left main CAD undergoing drug-eluting stent implantation. The proposed approach classified left main CAD as either extensive (n=819), defined as left main bifurcation lesions with an involvement of ostial left circumflex artery or as any left main lesion plus multivessel CAD, or limited (n=453), defined as ostial/midshaft lesions or left main bifurcation lesions without an involvement of ostium of left circumflex artery, alone or plus 1-vessel disease. The databases from 4 prospective Premier of Randomized Comparison of Bypass Surgery versus Angioplasty Using Sirolimus-Eluting Stent in Patients with Left Main Coronary Artery Disease studies were pooled, and the primary outcome was a major adverse cardiac event, defined as death, myocardial infarction, or repeat revascularization. During follow-up (median 38 months; interquartile range, 36-61 months), the risk for major adverse cardiac event was significantly higher with extensive than with limited left main CAD (adjusted hazard ratio, 2.13; 95% confidence interval, 1.54-2.94; P Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery score tertiles did not effectively stratify these 2 outcome measures. Compared with Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery scores, the simpler angiographic approach provided better discrimination for future cardiovascular events in patients with left main CAD undergoing drug-eluting stent implantation. © 2018 American Heart Association, Inc.

  20. Bootstrap rolling window estimation approach to analysis of the Environment Kuznets Curve hypothesis: evidence from the USA.

    Aslan, Alper; Destek, Mehmet Akif; Okumus, Ilyas

    2018-01-01

    This study aims to examine the validity of inverted U-shaped Environmental Kuznets Curve by investigating the relationship between economic growth and environmental pollution for the period from 1966 to 2013 in the USA. Previous studies based on the assumption of parameter stability and obtained parameters do not change over the full sample. This study uses bootstrap rolling window estimation method to detect the possible changes in causal relations and also obtain the parameters for sub-sample periods. The results show that the parameter of economic growth has increasing trend in 1982-1996 sub-sample periods, and it has decreasing trend in 1996-2013 sub-sample periods. Therefore, the existence of inverted U-shaped Environmental Kuznets Curve is confirmed in the USA.

  1. Retrospective analysis of the learning curve associated with laparoscopic ovariectomy in dogs and associated perioperative complication rates.

    Pope, Juliet Frances Anne; Knowles, Toby Grahame

    2014-08-01

    To assess the learning curve associated with laparoscopic ovariectomy (LOE) in 618 dogs and to report perioperative complication rates. Case series. Dogs (n = 618). Data retrieved from the medical records of bitches admitted for LOE over 42 months included date of surgery, breed, weight (kg), age (months), surgeon, suture material used, intraoperative complications and postoperative complications. Each LOE was defined as "successful" or "unsuccessful" by the absence or presence of an intraoperative complication and "failure" rate described using a CUSUM technique. Follow-up time ranged from 152 to 1,435 days (median, 737 days). Intraoperative complications occurred in 10 dogs (1.6%) and included: splenic laceration (6 dogs; 1%), urinary bladder perforation (3 dogs; 0.5%), and subcutaneous emphysema (1 dog; 0.2%). Postoperative complications occurred in 99 dogs (16%) and included: incisional inflammation treated with antibiotics (87 dogs [14%]; 96/1,854 incisions; 5.1%), incisional seroma (5 dogs [0.8%]; 5/1,854 incisions, 0.3%), incisional hernia (4 dogs [0.6%]; 4/1,854 incisions, 0.2%), and ovarian remnant syndrome (3 dogs; 0.5%). CUSUM charts indicated an initial "learning curve" of ∼80 LOE. LOE is a technique with an initial learning curve but once surgical proficiency is reached after ∼80 procedures then intraoperative complication rates associated with the procedure can be low. © Copyright 2014 by The American College of Veterinary Surgeons.

  2. Problems in using p-curve analysis and text-mining to detect rate of p-hacking and evidential value.

    Bishop, Dorothy V M; Thompson, Paul A

    2016-01-01

    Background. The p-curve is a plot of the distribution of p-values reported in a set of scientific studies. Comparisons between ranges of p-values have been used to evaluate fields of research in terms of the extent to which studies have genuine evidential value, and the extent to which they suffer from bias in the selection of variables and analyses for publication, p-hacking. Methods. p-hacking can take various forms. Here we used R code to simulate the use of ghost variables, where an experimenter gathers data on several dependent variables but reports only those with statistically significant effects. We also examined a text-mined dataset used by Head et al. (2015) and assessed its suitability for investigating p-hacking. Results. We show that when there is ghost p-hacking, the shape of the p-curve depends on whether dependent variables are intercorrelated. For uncorrelated variables, simulated p-hacked data do not give the "p-hacking bump" just below .05 that is regarded as evidence of p-hacking, though there is a negative skew when simulated variables are inter-correlated. The way p-curves vary according to features of underlying data poses problems when automated text mining is used to detect p-values in heterogeneous sets of published papers. Conclusions. The absence of a bump in the p-curve is not indicative of lack of p-hacking. Furthermore, while studies with evidential value will usually generate a right-skewed p-curve, we cannot treat a right-skewed p-curve as an indicator of the extent of evidential value, unless we have a model specific to the type of p-values entered into the analysis. We conclude that it is not feasible to use the p-curve to estimate the extent of p-hacking and evidential value unless there is considerable control over the type of data entered into the analysis. In particular, p-hacking with ghost variables is likely to be missed.

  3. Intensity ratio curve analysis of small renal masses on T2-weighted magnetic resonance imaging: Differentiation of fat-poor angiomyolipoma from renal cell carcinoma.

    Moriyama, Shingo; Yoshida, Soichiro; Tanaka, Hajime; Tanaka, Hiroshi; Yokoyama, Minato; Ishioka, Junichiro; Matsuoka, Yoh; Saito, Kazutaka; Kihara, Kazunori; Fujii, Yasuhisa

    2018-03-25

    To assess the diagnostic ability of a pixel intensity-based analysis in evaluating the magnetic resonance imaging characteristics of small renal masses, especially in differentiating fat-poor angiomyolipoma from renal cell carcinoma. T2-weighted images from 121 solid small renal masses (ratio curve was plotted using intensity ratios, which were ratios of signal intensities of tumor pixels (each pixel along a linear region of interest drawn across the renal tumor on T2-weighted image) to the signal intensity of a normal renal cortex. The diagnostic ability of the intensity ratio curve analysis was evaluated. The tumors were classified into three types: intensity ratio fat-poor angiomyolipoma (n = 19) with no pseudocapsule, iso-low intensity and no heterogeneity; intensity ratio clear cell renal cell carcinoma (n = 76) with a pseudocapsule, iso-high intensity and heterogeneity; and other type of intensity ratio (n = 26), including tumors that did not fall into the above two categories. The sensitivity/specificity/accuracy of the intensity ratio curve analysis in diagnosing fat-poor angiomyolipoma was 93%/94%/94%, respectively. When the intensity ratio curve analysis was applied only to the tumor with undetermined radiological diagnosis, the sensitivity for diagnosing fat-poor angiomyolipoma compared with subjective reading alone significantly improved (93% vs 50%; P = 0.014). Our novel semiquantitative model for combined assessment of key features of fat-poor angiomyolipoma, including low intensity, homogeneity and absence of a pseudocapsule on T2-weighted image, might make diagnosis of fat-poor angiomyolipoma more accurate. © 2018 The Japanese Urological Association.

  4. Experimental and micromagnetic first-order reversal curves analysis in NdFeB-based bulk 'exchange spring'-type permanent magnets

    Chiriac, Horia [National Institute of Research and Development for Technical Physics, 47 Mangeron Boulevard, 700050, Iasi (Romania); Lupu, Nicoleta [National Institute of Research and Development for Technical Physics, 47 Mangeron Boulevard, 700050, Iasi (Romania); Stoleriu, Laurentiu [Al. I. Cuza University, Department of Solid State and Theoretical Physics, Blvd. Carol I, 11, 700506, Iasi (Romania)]. E-mail: lstoler@uaic.ro; Postolache, Petronel [Al. I. Cuza University, Department of Solid State and Theoretical Physics, Blvd. Carol I, 11, 700506, Iasi (Romania); Stancu, Alexandru [Al. I. Cuza University, Department of Solid State and Theoretical Physics, Blvd. Carol I, 11, 700506, Iasi (Romania)

    2007-09-15

    In this paper we present the results of applying the first-order reversal curves (FORC) diagram experimental method to the analysis of the magnetization processes of NdFeB-based permanents magnets. The FORC diagrams for this kind of exchange spring magnets show the existence of two magnetic phases-a soft magnetic phase and a hard magnetic one. Micromagnetic modeling is used for validating the hypotheses regarding the origin of the different features of the experimental FORC diagrams.

  5. Assessment of genetic mutations in the XRCC2 coding region by high resolution melting curve analysis and the risk of differentiated thyroid carcinoma in Iran

    Shima Fayaz

    2012-01-01

    Full Text Available Homologous recombination (HR is the major pathway for repairing double strand breaks (DSBs in eukaryotes and XRCC2 is an essential component of the HR repair machinery. To evaluate the potential role of mutations in gene repair by HR in individuals susceptible to differentiated thyroid carcinoma (DTC we used high resolution melting (HRM analysis, a recently introduced method for detecting mutations, to examine the entire XRCC2 coding region in an Iranian population. HRM analysis was used to screen for mutations in three XRCC2 coding regions in 50 patients and 50 controls. There was no variation in the HRM curves obtained from the analysis of exons 1 and 2 in the case and control groups. In exon 3, an Arg188His polymorphism (rs3218536 was detected as a new melting curve group (OR: 1.46; 95%CI: 0.432-4.969; p = 0.38 compared with the normal melting curve. We also found a new Ser150Arg polymorphism in exon 3 of the control group. These findings suggest that genetic variations in the XRCC2 coding region have no potential effects on susceptibility to DTC. However, further studies with larger populations are required to confirm this conclusion.

  6. 51Cr - erythrocyte survival curves

    Paiva Costa, J. de.

    1982-07-01

    Sixteen patients were studied, being fifteen patients in hemolytic state, and a normal individual as a witness. The aim was to obtain better techniques for the analysis of the erythrocytes, survival curves, according to the recommendations of the International Committee of Hematology. It was used the radiochromatic method as a tracer. Previously a revisional study of the International Literature was made in its aspects inherent to the work in execution, rendering possible to establish comparisons and clarify phonomena observed in cur investigation. Several parameters were considered in this study, hindering both the exponential and the linear curves. The analysis of the survival curves of the erythrocytes in the studied group, revealed that the elution factor did not present a homogeneous answer quantitatively to all, though, the result of the analysis of these curves have been established, through listed programs in the electronic calculator. (Author) [pt

  7. CT and angiographic appearances of hepatocellular carcinoma partially fed by right inferior phrenic artery

    Ohtomo, Kuni; Furui, Shigeru; Yoshikawa, Hiroki; Yashiro, Naofumi; Araki, Tsutomu [Tokyo Univ. (Japan). Faculty of Medicine

    1983-04-01

    CT and angiographic appearances of 8 hepatocellular carcinomas which were partially fed by right inferior phrenic artery were discussed. CT demonstrated tumor fully occupied posterior segment of right hepatic lobe in 6 cases which were composed of 3 solitary massive, 2 massive nodular and 1 confluent massive angiographically. In the other 2 cases, CT showed encapsulated tumor in posterior inferior portion of posterior segment protruded from the liver. In 6 out of these 8 cases, tumor vessels and tumor stain were chiefly derived from posterior branch of right inferior phrenic artery.

  8. Cerebral angiographic changes on serial examination of a patient with migraine

    Masuzawa, T.; Shinoda, S.; Nakahara, N.; Abe, F.; Sato, F.; Furuse, M.

    1983-03-01

    Curious cerebral angiographic changes are described in a 27-year-old female migraine patient. During the period of observation of this patient, both the intracranial carotid artery and the vertebrobasilar artery systems presented unusual and fascinating cerebral arteriographic pictures. In an attack of migraine, angiography showed that all the intracranial secondary and tertiary branches of the carotid arterial system were dilated without showing any changes in the extracranial arteries and when the migraine attack had subsided, all branches of the carotid arteries as well as the vertebrobasilar arteries demonstreated abnormal segmental narrowings or vasospasm. These sequential angiographic changes have not been hitherto reported in migraine.

  9. Angiographic study of digital arteries in workers exposed to vinyl chloride

    Falappa, P; Magnavita, N; Bergamaschi, A; Colavita, N

    1982-05-01

    Five patients exposed to vinyl chloride were studied by hand angiography and other non-invasive methods, including photoplethysmography, rheography, and thermography. Raynaud's phenomenon was present in all five subjects, while acro-osteolysis affected only one. Organic vascular lesions, such as narrowing, segmentary occlusions of digital arteries and bridge collaterals, were found in angiographic studies. Only one patient did not show clear segmentary occlusions, but his vessels were crooked and diffusely narrowed. Angiographic results appear to correlate well with the changes shown by non-invasive techniques.

  10. CT and angiographic appearances of hepatocellular carcinoma partially feeded by right inferior phrenic artery

    Ohtomo, Kuni; Furui, Shigeru; Yoshikawa, Hiroki; Yashiro, Naofumi; Araki, Tsutomu

    1983-01-01

    CT and angiographic appearances of 8 hepatocellular carcinomas which were partially feeded by right inferior phrenic artery were discussed. CT demonstrated tumor fully occupied posterior segment of right hepatic lobe in 6 cases which were composed of 3 solitary massive, 2 massive nodular and 1 confluent massive angiographically. In the other 2 cases, CT showed encapsulated tumor in posterior inferior portion of posterior segment protruded from the liver. In 6 out of these 8 cases, tumor vessels and tumor stain were chiefly derived from posterior branch of right inferior phrenic artery. (author)

  11. The pharmaco-kinetics of angiographic contrast media with special reference to the extravascular spaces. Fundamental studies on dogs for the characterization of angiographic media. Pt. 1

    Lagemann, K.

    1975-01-01

    The pharmaco-kinetics of angiographic contrast media in the extra-vascular space, which are largely unknown, were investigated experimentally in dogs. As part of a basic study, using radio-active contrast media, it was possible to determine the concentration and rate of elimination in practically all organs and tissues. Measurements were carried out first after prolonged infusion of contrast under conditions of balanced flow, and secondly six hours after the end of the infusion. It was therefore possible to determine the inflow and loss of contrast medium in various organs, or organs systems. The most commonly used angiographic contrast media in Germany were investigated. Their kinetic behaviour is largely identical, their pattern of distribution and elimination depended principally on the organ or tissue. (orig.) [de

  12. Clinical and angiographic predictors of haemodynamically significant angiographic lesions: development and validation of a risk score to predict positive fractional flow reserve.

    Sareen, Nishtha; Baber, Usman; Kezbor, Safwan; Sayseng, Sonny; Aquino, Melissa; Mehran, Roxana; Sweeny, Joseph; Barman, Nitin; Kini, Annapoorna; Sharma, Samin K

    2017-04-07

    Coronary revascularisation based upon physiological evaluation of lesions improves clinical outcomes. Angiographic or visual stenosis assessment alone is insufficient in predicting haemodynamic stenosis severity by fractional flow reserve (FFR) and therefore cannot be used to guide revascularisation, particularly in the lesion subset system formulated. Of 1,023 consecutive lesions (883 patients), 314 (31%) were haemodynamically significant. Characteristics associated with FFR ≤0.8 include male gender, higher SYNTAX score, lesions ≥20 mm, stenosis >50%, bifurcation, calcification, absence of tortuosity and smaller reference diameter. A user-friendly integer score was developed with the five variables demonstrating the strongest association. On prospective validation (in 279 distinct lesions), the increasing value of the score correlated well with increasing haemodynamic significance (C-statistic 0.85). We identified several clinical and angiographic characteristics and formulated a scoring system to guide the approach to intermediate lesions. This may translate into cost savings. Larger studies with prospective validation are required to confirm our results.

  13. Anatomical curve identification

    Bowman, Adrian W.; Katina, Stanislav; Smith, Joanna; Brown, Denise

    2015-01-01

    Methods for capturing images in three dimensions are now widely available, with stereo-photogrammetry and laser scanning being two common approaches. In anatomical studies, a number of landmarks are usually identified manually from each of these images and these form the basis of subsequent statistical analysis. However, landmarks express only a very small proportion of the information available from the images. Anatomically defined curves have the advantage of providing a much richer expression of shape. This is explored in the context of identifying the boundary of breasts from an image of the female torso and the boundary of the lips from a facial image. The curves of interest are characterised by ridges or valleys. Key issues in estimation are the ability to navigate across the anatomical surface in three-dimensions, the ability to recognise the relevant boundary and the need to assess the evidence for the presence of the surface feature of interest. The first issue is addressed by the use of principal curves, as an extension of principal components, the second by suitable assessment of curvature and the third by change-point detection. P-spline smoothing is used as an integral part of the methods but adaptations are made to the specific anatomical features of interest. After estimation of the boundary curves, the intermediate surfaces of the anatomical feature of interest can be characterised by surface interpolation. This allows shape variation to be explored using standard methods such as principal components. These tools are applied to a collection of images of women where one breast has been reconstructed after mastectomy and where interest lies in shape differences between the reconstructed and unreconstructed breasts. They are also applied to a collection of lip images where possible differences in shape between males and females are of interest. PMID:26041943

  14. Evaluation of the Capacity of PCR and High-Resolution Melt Curve Analysis for Identification of Mixed Infection with Mycoplasma gallisepticum Strains.

    Seyed A Ghorashi

    Full Text Available Pathogenicity and presentation of Mycoplasma gallisepticum (MG infection may differ from one strain to another and this may have implications on control measures. Infection of individual birds with more than one MG strain has been reported. A PCR followed by high resolution melt (HRM curve analysis has been developed in our laboratory and routinely used for detection and differentiation of MG strains. However the potential of this test for identification of MG strains in a mixed specimen has not been evaluated. In the present study, the capability of PCR-HRM curve analysis technique, targeting vlhA and pvpA genes was assessed for identification of individual MG strains in a mixed population. Different DNA ratios of two MG strains from 1 to 10(-4 ng were tested with some generated conventional and normalized curves distinct from those of individual strains alone. Using genotype confidence percentages (GCP generated from HRM curve analysis, it was found that vlhA PCR-HRM was more consistent than pvpA PCR-HRM for the detection of MG ts-11 vaccine strain mixed with any of the MG strains 6/85, F, S6 or a field isolate. The potential of vlhA PCR-HRM to detect mixed MG strains in a specimen was found to be primarily dependent on quantity and proportion of the target DNAs in the mixture. This is the first study examining the capacity of PCR-HRM technique for identification of individual MG strains in a mixed strain population.

  15. ECM using Edwards curves

    Bernstein, Daniel J.; Birkner, Peter; Lange, Tanja

    2013-01-01

    -arithmetic level are as follows: (1) use Edwards curves instead of Montgomery curves; (2) use extended Edwards coordinates; (3) use signed-sliding-window addition-subtraction chains; (4) batch primes to increase the window size; (5) choose curves with small parameters and base points; (6) choose curves with large...

  16. Direct Analysis of JV-Curves Applied to an Outdoor-Degrading CdTe Module (Presentation)

    Jordan, D; Kurtz, S.; Ulbrich, C.; Gerber, A.; Rau, U.

    2014-03-01

    We present the application of a phenomenological four parameter equation to fit and analyze regularly measured current density-voltage JV curves of a CdTe module during 2.5 years of outdoor operation. The parameters are physically meaningful, i.e. the short circuit current density Jsc, open circuit voltage Voc and differential resistances Rsc, and Roc. For the chosen module, the fill factor FF degradation overweighs the degradation of Jsc and Voc. Interestingly, with outdoor exposure, not only the conductance at short circuit, Gsc, increases but also the Gsc(Jsc)-dependence. This is well explained with an increase in voltage dependent charge carrier collection in CdTe.

  17. First-order reversal curve analysis in the hysteretic behavior of boron-rich nanocomposite Nd-Fe-B ribbons

    Saccone, F.D. [Laboratorio de Solidos Amorfos, Departamento de Fisica, Facultad de Ingenieria, Universidad de Buenos Aires (Argentina) and CONICET (Argentina)]. E-mail: fsaccon@fi.uba.ar; Pampillo, L.G. [Laboratorio de Solidos Amorfos, Departamento de Fisica, Facultad de Ingenieria, Universidad de Buenos Aires (Argentina); Oliva, M.I. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba (Argentina); CONICET (Argentina); Bercoff, P.G. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba (Argentina); CONICET (Argentina); Bertorello, H.R. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba (Argentina); CONICET (Argentina); Sirkin, H.R.M. [Laboratorio de Solidos Amorfos, Departamento de Fisica, Facultad de Ingenieria, Universidad de Buenos Aires (Argentina); CONICET (Argentina)

    2007-09-01

    Structural and magnetic properties of melt-spun Nd{sub 4.5}Fe{sub 72}Co{sub 3}Cr{sub 2}Al{sub 1}B{sub 17.5} ribbons were studied by means of differential scanning calorimetry, Moessbauer effect spectroscopy, X-ray diffraction and first-order reversal curve distributions. The presence of a solid solution (Fe, Co) in ribbons annealed at 685 C for 10 min was detected from Moessbauer spectra. Correlations between the observed structural changes at higher annealing temperatures and modifications in the interaction fields of precipitated phases are discussed.

  18. First-order reversal curve analysis in the hysteretic behavior of boron-rich nanocomposite Nd-Fe-B ribbons

    Saccone, F.D.; Pampillo, L.G.; Oliva, M.I.; Bercoff, P.G.; Bertorello, H.R.; Sirkin, H.R.M.

    2007-01-01

    Structural and magnetic properties of melt-spun Nd 4.5 Fe 72 Co 3 Cr 2 Al 1 B 17.5 ribbons were studied by means of differential scanning calorimetry, Moessbauer effect spectroscopy, X-ray diffraction and first-order reversal curve distributions. The presence of a solid solution (Fe, Co) in ribbons annealed at 685 C for 10 min was detected from Moessbauer spectra. Correlations between the observed structural changes at higher annealing temperatures and modifications in the interaction fields of precipitated phases are discussed

  19. Computerised curve deconvolution of TL/OSL curves using a popular spreadsheet program.

    Afouxenidis, D; Polymeris, G S; Tsirliganis, N C; Kitis, G

    2012-05-01

    This paper exploits the possibility of using commercial software for thermoluminescence and optically stimulated luminescence curve deconvolution analysis. The widely used software package Microsoft Excel, with the Solver utility has been used to perform deconvolution analysis to both experimental and reference glow curves resulted from the GLOw Curve ANalysis INtercomparison project. The simple interface of this programme combined with the powerful Solver utility, allows the analysis of complex stimulated luminescence curves into their components and the evaluation of the associated luminescence parameters.

  20. Computerised curve deconvolution of TL/OSL curves using a popular spreadsheet program

    Afouxenidis, D.; Polymeris, G. S.; Tsirliganis, N. C.; Kitis, G.

    2012-01-01

    This paper exploits the possibility of using commercial software for thermoluminescence and optically stimulated luminescence curve deconvolution analysis. The widely used software package Microsoft Excel, with the Solver utility has been used to perform deconvolution analysis to both experimental and reference glow curves resulted from the Glow Curve Analysis Intercomparison project. The simple interface of this programme combined with the powerful Solver utility, allows the analysis of complex stimulated luminescence curves into their components and the evaluation of the associated luminescence parameters. (authors)

  1. The role of stenosis ratio as a predictor of surgical satisfaction in patients with lumbar spinal canal stenosis: a receiver-operator characteristic (ROC) curve analysis.

    Mohammadi, Hassanreza R; Azimi, Parisa; Benzel, Edward C; Shahzadi, Sohrab; Azhari, Shirzad

    2016-09-01

    The aim of this study was to elucidate independent factors that predict surgical satisfaction in lumbar spinal canal stenosis (LSCS) patients. Patients who underwent surgery were grouped based on the age, gender, duration of symptoms, walking distance, Neurogenic Claudication Outcome Score (NCOS) and the stenosis ratio (SR) described by Lurencin. We recorded on 2-year patient satisfaction using standardized measure. The optimal cut-off points in SR, NCOS and walking distance for predicting surgical satisfaction were estimated from sensitivity and specificity calculations and receiver operator characteristic (ROC) curves. One hundred fifty consecutive patients (51 male, 99 female, mean age 62.4±10.9 years) were followed up for 34±13 months (range 24-49). One, two, three and four level stenosis was observed in 10.7%, 39.3%, 36.0 % and 14.0% of patients, respectively. Post-surgical satisfaction was 78.5% at the 2 years follow up. In ROC curve analysis, the asymptotic significance is less than 0.05 in SR and the optimal cut-off value of SR to predict worsening surgical satisfaction was measured as more than 0.52, with 85.4% sensitivity and 77.4% specificity (AUC 0.798, 95% CI 0.73-0.90; Ppatients with degenerative lumbar stenosis considered for surgical treatment. Using a ROC curve analysis, a radiological feature, the SR, demonstrated superiority in predicting patient satisfaction, compared to functional and clinical characteristics such as walking distance and NCOS.

  2. The learning curve to achieve satisfactory completion rates in upper GI endoscopy: an analysis of a national training database.

    Ward, S T; Hancox, A; Mohammed, M A; Ismail, T; Griffiths, E A; Valori, R; Dunckley, P

    2017-06-01

    The aim of this study was to determine the number of OGDs (oesophago-gastro-duodenoscopies) trainees need to perform to acquire competency in terms of successful unassisted completion to the second part of the duodenum 95% of the time. OGD data were retrieved from the trainee e-portfolio developed by the Joint Advisory Group on GI Endoscopy (JAG) in the UK. All trainees were included unless they were known to have a baseline experience of >20 procedures or had submitted data for 90% trainees had attained a 95% completion rate. Total number of OGDs performed, trainee age and experience in lower GI endoscopy were factors independently associated with OGD completion. There are limited published data on the OGD learning curve. This is the largest study to date analysing the learning curve for competency acquisition. The JAG competency requirement for 200 procedures appears appropriate. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  3. CONSTRUCTION OF AN EARTH MODEL: ANALYSIS OF EXOPLANET LIGHT CURVES AND MAPPING THE NEXT EARTH WITH THE NEW WORLDS OBSERVER

    Oakley, P. H. H.; Cash, W.

    2009-01-01

    The orbital light curve of a terrestrial exoplanet will likely contain valuable information about the surface and atmospheric features of the planet, both in its overall shape and hourly variations. We have constructed an empirically based code capable of simulating observations of the Earth from any orientation, at any time of year with continuously updated cloud and snow coverage with a New Worlds Observatory. By simulating these observations over a full orbital revolution at a distance of 10 pc we determine that the detection of an obliquity or seasonal terrain change is possible at low inclinations. In agreement with other studies, a 4 m New Worlds Observer can accurately determine the rotation rate of the planet at a success rate from ∼30% to 80% with only 5 days of observations depending on the signal to noise of the observations. We also attempt simple inversions of these diurnal light curves to sketch a map of the reflecting planet's surface features. This mapping technique is only successful with highly favorable systems and in particular requires that the cloud coverage must be lower than the Earth's average. Our test case of a 2 M + planet at 7 pc distance with low exo-zodiacal light and 25% cloud coverage produced crude, but successful results. Additionally, with these highly favorable systems NWO may be able to discern the presence of liquid surface water (or other smooth surfaces) though it requires a complex detection available only at crescent phases in high inclination systems.

  4. Using bivariate latent basis growth curve analysis to better understand treatment outcome in youth with anorexia nervosa.

    Byrne, Catherine E; Wonderlich, Joseph A; Curby, Timothy; Fischer, Sarah; Lock, James; Le Grange, Daniel

    2018-04-25

    This study explored the relation between eating-related obsessionality and weight restoration utilizing bivariate latent basis growth curve modelling. Eating-related obsessionality is a moderator of treatment outcome for adolescents with anorexia nervosa (AN). This study examined the degree to which the rate of change in eating-related obsessionality was associated with the rate of change in weight over time in family-based treatment (FBT) and individual therapy for AN. Data were drawn from a 2-site randomized controlled trial that compared FBT and adolescent focused therapy for AN. Bivariate latent basis growth curves were used to examine the differences of the relations between trajectories of body weight and symptoms associated with eating and weight obsessionality. In the FBT group, the slope of eating-related obsessionality scores and the slope of weight were significantly (negatively) correlated. This finding indicates that a decrease in overall eating-relating obsessionality is significantly associated with an increase in weight for individuals who received FBT. However, there was no relation between change in obsessionality scores and change in weight in the adolescent focused therapy group. Results suggest that FBT has a specific impact on both weight gain and obsessive compulsive behaviour that is distinct from individual therapy. Copyright © 2018 John Wiley & Sons, Ltd and Eating Disorders Association.

  5. Free Vibration Analysis of Functionally Graded Porous Doubly-Curved Shells Based on the First-Order Shear Deformation Theory

    Farajollah Zare Jouneghani

    2017-12-01

    Full Text Available Due to some technical issues that can appear during the manufacturing process of Functionally Graded Materials (FGMs, it can be extremely difficult to produce perfect materials. Indeed, one of the biggest problems is the presence of porosities. For this purpose, the vibrational behavior of doubly-curved shells made of FGM including porosities is investigated in this paper. With respect to previous research, the porosity has been added to the mechanical model that characterizes the through-the-thickness distribution of the graded constituents and applied to doubly-curved shell structures. Few papers have been published on this topic. In fact, it is easier to find works related to one-dimensional structures and beam models that take account the effect of porosities. The First-order Shear Deformation Theory (FSDT is considered as the theoretical framework. In addition, the mechanical properties of the constituents vary along the thickness direction. For this purpose, two power-law distributions are employed to characterize their volume fraction. Strain components are established in an orthogonal curvilinear coordinate system and the governing equations are derived according to the Hamilton’s principle. Finally, Navier’s solution method is used and the numerical results concerning three different types of shell structures are presented.

  6. An exploratory analysis of personality, attitudes, and study skills on the learning curve within a team-based learning environment.

    Persky, Adam M; Henry, Teague; Campbell, Ashley

    2015-03-25

    To examine factors that determine the interindividual variability of learning within a team-based learning environment. Students in a pharmacokinetics course were given 4 interim, low-stakes cumulative assessments throughout the semester and a cumulative final examination. Students' Myers-Briggs personality type was assessed, as well as their study skills, motivations, and attitudes towards team-learning. A latent curve model (LCM) was applied and various covariates were assessed to improve the regression model. A quadratic LCM was applied for the first 4 assessments to predict final examination performance. None of the covariates examined significantly impacted the regression model fit except metacognitive self-regulation, which explained some of the variability in the rate of learning. There were some correlations between personality type and attitudes towards team learning, with introverts having a lower opinion of team-learning than extroverts. The LCM could readily describe the learning curve. Extroverted and introverted personality types had the same learning performance even though preference for team-learning was lower in introverts. Other personality traits, study skills, or practice did not significantly contribute to the learning variability in this course.

  7. Three-dimensional flow analysis and improvement of slip factor model for forward-curved blades centrifugal fan

    Guo, En Min; Kim, Kwang Yong

    2004-01-01

    This work developed improved slip factor model and correction method to predict flow through impeller in forward-curved centrifugal fan. Both steady and unsteady three-dimensional CFD analyses were performed to validate the slip factor model and the correction method. The results show that the improved slip factor model presented in this paper could provide more accurate predictions for forward-curved centrifugal impeller than the other slip factor models since the present model takes into account the effect of blade curvature. The correction method is provided to predict mass-averaged absolute circumferential velocity at the exit of impeller by taking account of blockage effects induced by the large-scale backflow near the front plate and flow separation within blade passage. The comparison with CFD results also shows that the improved slip factor model coupled with the present correction method provides accurate predictions for mass-averaged absolute circumferential velocity at the exit of impeller near and above the flow rate of peak total pressure coefficient

  8. Geometrically nonlinear dynamic analysis of doubly curved isotropic shells resting on elastic foundation by a combination of harmonic differential quadrature-finite difference methods

    Civalek, Oemer

    2005-01-01

    The nonlinear dynamic response of doubly curved shallow shells resting on Winkler-Pasternak elastic foundation has been studied for step and sinusoidal loadings. Dynamic analogues of Von Karman-Donnel type shell equations are used. Clamped immovable and simply supported immovable boundary conditions are considered. The governing nonlinear partial differential equations of the shell are discretized in space and time domains using the harmonic differential quadrature (HDQ) and finite differences (FD) methods, respectively. The accuracy of the proposed HDQ-FD coupled methodology is demonstrated by numerical examples. The shear parameter G of the Pasternak foundation and the stiffness parameter K of the Winkler foundation have been found to have a significant influence on the dynamic response of the shell. It is concluded from the present study that the HDQ-FD methodolgy is a simple, efficient, and accurate method for the nonlinear analysis of doubly curved shallow shells resting on two-parameter elastic foundation

  9. MYOCARDIAL BRIDGING - CLINICAL AND ANGIOGRAPHIC PROFILE IN LAST 5 YEARS; A STUDY OF 129 CASES

    Abhilash S P

    2010-11-01

    Full Text Available Aims of study : To assess the clinical and angiographical profile of myocardial bridging from consecutive coronary angiograms done over last 5 years at Medical college, Thiruvananthapuram. To assess the risk of cardiovascular events and the risk of accelerated atherosclerosis in isolated myocardial bridging. Methods : Consecutive coronary angiograms done at Medical college Thiruvananthapuram from 04/02/2005 to 31/03/2010 were reviewed for myocardial bridging. A total of 10492 coronary angiograms were reviewed. Myocardial bridges with systolic lumen reduction of more than 50% were considered for analysis. Quantitative coronary angiography (QCA was used for analysis. Clinical presentation as well as correlation with structural heart disease and coronary heart disease was assessed. Results: Incidence of myocardial bridges was 1.23%. Of the 129 patients with myocardial bridges 63 ( 48.8% had associated significant coronary artery disease. Remaining 66 (51.2% patients presented with isolated bridges. Out of these 66 patients with isolated myocardial bridges, 7 (10.6% patients presented with acute myocardial infarction and 3 (4.5% presented with cardiac arrhythmias. Of the 63 patients with significant coronary disease 11 (17.5% patients had single vessel disease and they had the culprit lesion and myocardial bridge seen in the same vessel. Most common location of myocardial bridge was mid LAD (64.9% followed by distal LAD (23.8%. Length of bridge was 20 mm in 35.7%. Mean percentage of systolic obliteration by the bridge was 74.5%. 100% systolic obliteration was seen in 7.79% of isolated bridges and in 9.79% of bridges with CAD. Among 120 rhuematic heart disease patients who underwent coronary angiogram, 10 (8.3% patients had myocardial bridging. 12.1% of all HCM patients who underwent coronary angiograms had myocardial bridging. Conclusion: Myocardial bridging can be lethal- can accelerate atherosclerosis, can precipitate acute MIs and life

  10. Kinetic analysis of enzyme systems with suicide substrate in the presence of a reversible competitive inhibitor, tested by simulated progress curves.

    Moruno-Dávila, M A; Garrido-del Solo, C; García-Moreno, M; Havsteen, B H; Garcia-Sevilla, F; Garcia-Cánovas, F; Varón, R

    2001-02-01

    The use of suicide substrates remains a very important and useful method in enzymology for studying enzyme mechanisms and designing potential drugs. Suicide substrates act as modified substrates for the target enzymes and bind to the active site. Therefore the presence of a competitive reversible inhibitor decreases the rate of substrate-induced inactivation and protects the enzyme from this inactivation. This lowering on the inactivation rate has evident physiological advantages, since it allows the easy acquisition of experimental data and facilitates kinetic data analysis by providing another variable (inhibitor concentration). However despite the importance of the simultaneous action of a suicide substrate and a competitive reversible inhibition, to date no corresponding kinetic analysis has been carried out. Therefore we present a general kinetic analysis of a Michaelis-Menten reaction mechanism with double inhibition caused by both, a suicide substrate and a competitive reversible inhibitor. We assume rapid equilibrium of the reversible reaction steps involved, while the time course equations for the reaction product have been derived with the assumption of a limiting enzyme. The goodness of the analytical solutions has been tested by comparison with the simulated curves obtained by numerical integration. A kinetic data analysis to determine the corresponding kinetic parameters from the time progress curve of the product is suggested. In conclusion, we present a complete kinetic analysis of an enzyme reaction mechanism as described above in an attempt to fill a gap in the theoretical treatment of this type of system.

  11. Experimental analysis of waveform effects on satellite and ligament behavior via in situ measurement of the drop-on-demand drop formation curve and the instantaneous jetting speed curve

    Kwon, Kye-Si

    2010-01-01

    In situ techniques to measure the drop-on-demand (DOD) drop formation curve and the instantaneous jetting speed curve are developed such that ligament behavior and satellite behavior of inkjet droplets can be analyzed effectively. It is known that the droplet jetting behavior differs by ink properties and the driving waveform voltage. In this study, to reduce possible droplet placement errors due to satellite drops or long ligaments during printing, waveform effects on drop formation are investigated based on the measured DOD drop formation curve and the instantaneous jetting speed curve. Experimental results show that a dwell time greater than the so-called efficient dwell time was effective in reducing placement errors due to satellite drops during the printing process

  12. Cognitive deficits after aneurysmal and angiographically negative subarachnoid hemorrhage : Memory, attention, executive functioning, and emotion recognition

    Buunk, Anne M; Groen, Rob J M; Veenstra, Wencke S; Metzemaekers, Joannes; van der Hoeven, Johannes H; van Dijk, J Marc C; Spikman, Jacoba M

    2016-01-01

    OBJECTIVE: The authors' aim was to investigate cognitive outcome in patients with aneurysmal and angiographically negative subarachnoid hemorrhage (aSAH and anSAH), by comparing them to healthy controls and to each other. Besides investigating cognitive functions as memory and attention, they

  13. Should incidental asymptomatic angiographic stenoses and occlusions be treated in patients with peripheral arterial disease?

    Keeling, Aoife N

    2009-09-01

    The clinical importance of angiographically detected asymptomatic lower-limb stenoses and occlusions is unknown. This study aims to (i) assess the clinical outcome of asymptomatic lesions in the lower limb, (ii) identify predictors of clinical deterioration, and (iii) determine which asymptomatic lower-limb lesions should be treated at presentation.

  14. Economic evaluation of angiographic interventions including a whole-radiology in- and outpatient care

    Nolte-Ernsting, C.; Abel, K.; Krupski, G.; Lorenzen, J.; Adam, G.

    2006-01-01

    Purpose: To determine the economic efficiency of a whole-radiology in- and outpatient treatment with angiographic interventions performed as the main or sole therapy. Materials and Methods: The calculations represent the data of a university radiology department, including the following angiographic interventions (neuroradiology not considered): Vascular intervention (PTA, stent implantation) of kidneys and extremities, recanalization of hemodialysis access, chemoembolization, diagnostic arterioportal liver CT, port implantation, varicocele embolization, PTCD, percutaneous implantation of biliary stent. First, the different angiographic interventions are categorized with reference to the German DRG system 2005. Considering the example of a university hospital, the individual cost of each intervention is calculated and correlated with reimbursements by G-DRG2005 and so-called ''ambulant operation'' (EBM200plus). With these data, profits and losses are calculated for both in- and outpatient care. Results: Radiologic interventions of inpatients yield a profit in the majority of cases. With a base rate of 2900 Euro, the profits in our university hospital range between -872 Euro and +3411 Euro (mean: +1348 Euro). On the other hand, those angiographic interventions suitable for ''ambulant operation'' generate average profits of +372 Euro, if only direct costs are considered. The data of outpatient radiological interventions average between 381 Euro up to 1612 Euro lower than compared with profits obtained from in patient care. (orig.)

  15. Risk factors and short-term outcome in patients with angiographically negative subarachnoid hemorrhage

    Dalbjerg, Sara Maria; Larsen, Carl Christian; Romner, Bertil

    2013-01-01

    The objective of this study was to identify prognostic factors for clinical outcome in patients with non-traumatic, angiographically negative subarachnoid hemorrhage. Furthermore, the aim was to investigate if patients on anticoagulant therapy may have a more unfavorable outcome than patients...

  16. Sensitivity equation for quantitative analysis with multivariate curve resolution-alternating least-squares: theoretical and experimental approach.

    Bauza, María C; Ibañez, Gabriela A; Tauler, Romà; Olivieri, Alejandro C

    2012-10-16

    A new equation is derived for estimating the sensitivity when the multivariate curve resolution-alternating least-squares (MCR-ALS) method is applied to second-order multivariate calibration data. The validity of the expression is substantiated by extensive Monte Carlo noise addition simulations. The multivariate selectivity can be derived from the new sensitivity expression. Other important figures of merit, such as limit of detection, limit of quantitation, and concentration uncertainty of MCR-ALS quantitative estimations can be easily estimated from the proposed sensitivity expression and the instrumental noise. An experimental example involving the determination of an analyte in the presence of uncalibrated interfering agents is described in detail, involving second-order time-decaying sensitized lanthanide luminescence excitation spectra. The estimated figures of merit are reasonably correlated with the analytical features of the analyzed experimental system.

  17. Microlocal analysis of quantum fields on curved space-times: Analytic wave front sets and Reeh-Schlieder theorems

    Strohmaier, Alexander; Verch, Rainer; Wollenberg, Manfred

    2002-01-01

    We show in this article that the Reeh-Schlieder property holds for states of quantum fields on real analytic curved space-times if they satisfy an analytic microlocal spectrum condition. This result holds in the setting of general quantum field theory, i.e., without assuming the quantum field to obey a specific equation of motion. Moreover, quasifree states of the Klein-Gordon field are further investigated in the present work and the (analytic) microlocal spectrum condition is shown to be equivalent to simpler conditions. We also prove that any quasifree ground or KMS state of the Klein-Gordon field on a stationary real analytic space-time fulfills the analytic microlocal spectrum condition

  18. ANALYSIS OF CULTURAL ADAPTATION OF INTERNATIONAL STUDENTS UNDER THE POINT OF VIEW OF THE CURVE THEORY "U" AND "W"

    Luciane Stallivieri

    2015-11-01

    Full Text Available Students from around the world are increasingly interested in learning new languages and be inserted in different cultures, increasing the numbers of international mobility. However, when traveling to another country, cultural differences are strongly perceived, even if in different ways, influencing the adaptation process. Given the importance and growth of the international academic mobility, this study analyzes the process of cultural adaptation of students in mobility, considering the assumptions of the theory of curves "U" and "W". As for the methodology, it is a descriptive research with quantitative approach. Data collection was conducted through closed questionnaires sent to international students from different countries who have studied or are still studying in a Brazilian Institution of Higher Education. The results showed that after the stage of culture shock, students feel more connected to local culture, make more friends and feel more confident. It was confirmed also that almost all international students managed to adapt well to local customs.

  19. The influence of maternal care and overprotection on youth adrenocortical stress response: a multiphase growth curve analysis.

    Vergara-Lopez, Chrystal; Chaudoir, Stephenie; Bublitz, Margaret; O'Reilly Treter, Maggie; Stroud, Laura

    2016-11-01

    We examined the association between two dimensions of maternal parenting style (care and overprotection) and cortisol response to an acute laboratory-induced stressor in healthy youth. Forty-three participants completed the Parental Bonding Instrument and an adapted version of the Trier Social Stress Test-Child (TSST-C). Nine cortisol samples were collected to investigate heterogeneity in different phases of youth's stress response. Multiphase growth-curve modeling was utilized to create latent factors corresponding to individual differences in cortisol during baseline, reactivity, and recovery to the TSST-C. Youth report of maternal overprotection was associated with lower baseline cortisol levels, and a slower cortisol decline during recovery, controlling for maternal care, puberty, and gender. No additive or interactive effects involving maternal care emerged. These findings suggest that maternal overprotection may exert a unique and important influence on youth's stress response.

  20. Gender and Facebook motives as predictors of specific types of Facebook use: A latent growth curve analysis in adolescence.

    Frison, Eline; Eggermont, Steven

    2016-10-01

    Despite increasing evidence that specific types of Facebook use (i.e., active private, active public, and passive Facebook use) are differently related to adolescents' well-being, little is known how these types function over the course of adolescence and whether gender and Facebook motives may predict the initial level and changes in these types over time. To address these gaps, Flemish adolescents (ages 12-19) were questioned at three different time points, with six months in between (NTime1 = 1866). Latent growth curve models revealed that active private Facebook use increased over the course of adolescence, whereas public Facebook use decreased. Passive Facebook use, however, remained stable. In addition, gender and Facebook motives were related to initial levels of specific types of Facebook use, and predictive of dynamic change in specific types of Facebook use over time. The discussion focuses on the understanding and implications of these findings. Copyright © 2016. Published by Elsevier Ltd.