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Sample records for left radial approaches

  1. Randomized comparison of transradial coronary angiography via right or left radial artery approaches.

    PubMed

    Kanei, Yumiko; Nakra, Navin C; Liou, Michael; Vales, Lori L; Gowda, Ramesh; Rosero, Hugo; Kwan, Tak; Fox, John T

    2011-01-15

    Previous studies have shown that the right radial approach encounters more tortuosity than the left radial approach during transradial coronary angiography. The objective of this study was to compare the procedural difficulty of the right and left radial approaches in the modern era with dedicated transradial catheters. One hundred ninety-three patients scheduled for transradial coronary angiography with normal Allen test results and without histories of coronary artery bypass grafting were randomized to the right or left radial approach. The choice of catheter was left to the discretion of the operator, with the preferred catheter being a dedicated transradial Optitorque catheter. The primary end point was procedural difficulty, defined as (1) hydrophilic or coronary wire use for tortuosity, (2) stiff wire use for the coronary engagement, (3) multiple catheters used, or (4) nonselective injection. The clinical characteristics were similar between the 2 groups. Procedural success was achieved in 98 of 101 (98%) in the right radial group and 91 of 92 (99%) in the left radial group. Procedural difficulty, fluoroscopy time, and contrast use were similar between the 2 groups. The use of a single catheter was more common in the right radial group (73% vs 18%, p <0.001). In conclusion, procedural success and difficulty were similar in the comparison groups. The right and left radial approaches are feasible and effective to perform coronary angiography and intervention.

  2. [Right versus left radial artery approach for coronary angiography. Differences observed and the learning curve].

    PubMed

    Fernández-Portales, Javier; Valdesuso, Raúl; Carreras, Raúl; Jiménez-Candil, Javier; Serrador, Ana; Romaní, Sebastián

    2006-10-01

    There are anatomical differences between right and left radial artery approaches for coronary catheterization that could influence application of the technique. We present the results of a randomized study that compared the effectiveness of the two approaches and identified factors associated with failure of the procedure. The study involved 351 consecutive patients: a left radial approach was used in 180, and a right radial approach, in 171. The procedure could not be completed using the initial approach selected in 15 patients (11 right radial vs. 4 left radial; P=.007). Use of a right radial approach, lack of catheterization experience, patient age >70 years, and the absence of hypertension were found to be independently associated with prolonged fluoroscopy duration and failure using the initial approach. Use of the right radial approach in patients aged over 70 years was associated with a 6-fold increase in the risk of an adverse event. Consequently, use of the right radial approach should be avoided in patients aged over 70 years when trainee practitioners are on the learning curve.

  3. Comparison of the feasibility and effectiveness of transradial coronary angiography via right versus left radial artery approaches (from the PREVAIL Study).

    PubMed

    Pelliccia, Francesco; Trani, Carlo; Biondi-Zoccai, Giuseppe G L; Nazzaro, Marco; Berni, Andrea; Patti, Giuseppe; Patrizi, Roberto; Pironi, Bruno; Mazzarotto, Pietro; Gioffrè, Gaetano; Speciale, Giulio; Pristipino, Christian

    2012-09-15

    It remains undefined if transradial coronary angiography from a right or left radial arterial approach differs in real-world practice. To address this issue, we performed a subanalysis of the PREVAIL study. The PREVAIL study was a prospective, multicenter, observational survey of unselected consecutive patients undergoing invasive cardiovascular procedures over a 1-month observation period, specifically aimed at assessing the outcomes of radial approach in the contemporary real world. The choice of arterial approach was left to the discretion of the operator. Prespecified end points of this subanalysis were procedural characteristics. Of 1,052 patients consecutively enrolled, 509 patients underwent transradial catheterization, 304 with a right radial and 205 with a left radial approach. Procedural success rates were similar between the 2 groups. Compared to the left radial group, the right radial group had longer procedure duration (46 ± 29 vs 33 ± 24 minutes, p <0.0001) and fluoroscopy time (765 ± 787 vs 533 ± 502, p <0.0001). At multivariate analysis, including a parsimonious propensity score for the choice of left radial approach, duration of procedure (beta coefficient 11.38, p <0.001) and total dose-area product (beta coefficient 11.38, p <0.001) were independently associated with the choice of the left radial artery approach. The operator's proficiency in right/left radial approach did not influence study results. In conclusion, right and left radial approaches are feasible and effective to perform percutaneous procedures. In the contemporary real world, however, the left radial route is associated with shorter procedures and lower radiologic exposure than the right radial approach, independently of an operator's proficiency.

  4. Comparative efficacy and safety of the left versus right radial approach for percutaneous coronary procedures: a meta-analysis including 6870 patients.

    PubMed

    Xia, S L; Zhang, X B; Zhou, J S; Gao, X

    2015-08-01

    The radial approach is widely used in the treatment of patients with coronary artery disease. We conducted a meta-analysis of published results on the efficacy and safety of the left and right radial approaches in patients undergoing percutaneous coronary procedures. A systematic search of reference databases was conducted, and data from 14 randomized controlled trials involving 6870 participants were analyzed. The left radial approach was associated with significant reductions in fluoroscopy time [standardized mean difference (SMD)=-0.14, 95% confidence interval (CI)=-0.19 to -0.09; P<0.00001] and contrast volume (SMD=-0.07, 95%CI=-0.12 to -0.02; P=0.009). There were no significant differences in rate of procedural failure of the left and the right radial approaches [risk ratios (RR)=0.98; 95%CI=0.77-1.25; P=0.88] or procedural time (SMD=-0.05, 95%CI=0.17-0.06; P=0.38). Tortuosity of the subclavian artery (RR=0.27, 95%CI=0.14-0.50; P<0.0001) was reported more frequently with the right radial approach. A greater number of catheters were used with the left than with the right radial approach (SMD=0.25, 95%CI=0.04-0.46; P=0.02). We conclude that the left radial approach is as safe as the right radial approach, and that the left radial approach should be recommended for use in percutaneous coronary procedures, especially in percutaneous coronary angiograms.

  5. Analysis of radial basis function interpolation approach

    NASA Astrophysics Data System (ADS)

    Zou, You-Long; Hu, Fa-Long; Zhou, Can-Can; Li, Chao-Liu; Dunn, Keh-Jim

    2013-12-01

    The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical properties in the laboratory on the basis of physical rock datasets, which include the formation factor, viscosity, permeability, and molecular composition. However, this approach does not consider the effect of spatial distribution of the calibration data on the interpolation result. This study proposes a new RBF interpolation approach based on the Freedman's RBF interpolation approach, by which the unit basis functions are uniformly populated in the space domain. The inverse results of the two approaches are comparatively analyzed by using our datasets. We determine that although the interpolation effects of the two approaches are equivalent, the new approach is more flexible and beneficial for reducing the number of basis functions when the database is large, resulting in simplification of the interpolation function expression. However, the predicted results of the central data are not sufficiently satisfied when the data clusters are far apart.

  6. Right and left heart catheterization via an antecubital fossa vein and the radial artery--a prospective study.

    PubMed

    Williams, Paul D; Palmer, Sonny; Judkins, Chris; Gutman, Jack; Whitbourn, Rob; MacIsaac, Andrew; Xu, Bo; Burns, Andrew; Wilson, Andrew

    2014-12-01

    Right heart catheterization has been described via the arm but previous reports have been retrospective, performed for limited indications, and may not give an accurate assessment of the success rate or safety of this technique. We sought to prospectively examine the feasibility and safety of left and right heart catheterization entirely via the arm using the radial artery and an antecubital fossa vein for a broad range of indications. Fifty-eight consecutive procedures were included. Transradial arterial access was successful in 57 patients (98%), right heart catheterization via the antecubital fossa vein was successful in 54 patients (93%) and bilateral catheterization from the arm was achieved in 53 patients (91%). Standard diagnostic catheterization was the most frequent procedure (59%), although thermodilution (6.9%), percutaneous coronary intervention (33%), and coronary sinus sampling (16%) were also performed in selected cases. Compared to a historical cohort of patients undergoing right and left heart catheterization via femoral access, mean procedural time (38 vs 47 minutes; P=.03) and screening time (8.1 vs 11.2 minutes; P<.001) were significantly reduced. There was 1 venous forearm hematoma that was managed conservatively. Right and left heart catheterization can be performed routinely via the arm in a broad range of patients and is associated with reduced procedural and fluoroscopy time as compared to femoral access. This approach can be considered for all patients in whom right and left heart catheterization is planned.

  7. Radial Artery Approach to Salvage Nonmaturing Radiocephalic Arteriovenous Fistulas

    SciTech Connect

    Hsieh, Mu-Yang; Lin, Lin; Tsai, Kuei-Chin; Wu, Chih-Cheng

    2013-08-01

    PurposeTo evaluate the usefulness of an approach through the radial artery distal to the arteriovenous anastomosis for salvaging nonmaturing radiocephalic arteriovenous fistulas.MethodsProcedures that fulfilled the following criteria were retrospectively reviewed: (1) autogenous radiocephalic fistulas, (2) fistulas less than 3 months old, (3) distal radial artery approach for salvage. From 2005 to 2011, a total of 51 patients fulfilling the above criteria were enrolled. Outcome variables were obtained from angiographic, clinical and hemodialysis records, including the success, complication, and primary and secondary patency rates.ResultsThe overall anatomical and clinical success rates for the distal radial artery approach were 96 and 94 %, respectively. The average procedure time was 36 {+-} 19 min. Six patients (12 %) experienced minor complications as a result of extravasations. No arterial complication or puncture site complication was noted. The postinterventional 6-month primary patency rate was 51 %, and the 6-month secondary patency rate was 90 %. When the patients were divided into a stenosed group (20 patients) and an occluded group (31 patients), there were no differences in the success rate, complication rate, or primary and secondary patency rates.ConclusionAn approach through the radial artery distal to the arteriovenous anastomosis is an effective and safe alternative for the salvage of nonmaturing radiocephalic arteriovenous fistulas, even for occluded fistulas.

  8. A new approach to radial and axial gauges

    NASA Astrophysics Data System (ADS)

    Weigert, Heribert; Heinz, Ulrich

    1992-03-01

    We develop a new path integral formulation of QCD in radial and axial gauges. This formalism yields free propagators which are free of gauge poles. We find that radial gauges are ghost free. In axial gauges ghosts cannot generally be excluded from the formalism due to the need to fix the residual gauge freedom.

  9. Renal Stenting from the Radial Artery: A Novel Approach

    SciTech Connect

    Kessel, David O.; Robertson, Iain; Taylor, Edward J.; Patel, Jai V.

    2003-04-15

    Purpose: To describe the technique and feasibility of renal artery angioplasty and stenting from the radial artery. Methods: A series of 19 patients were evaluated for transradial renal artery intervention. Procedures were performed using carbon dioxide gas (CO{sub 2}) as the preferred angiographic contrast agent. Intervention was performed through a 5 Fr radial artery sheath using low-profile balloons and balloon-expandable stents. Results: Nineteen patients with 26 stenosed renal arteries were considered for treatment via the radial route. A negative Allen's test precluded radial puncture in two (11%). In one patient the descending aorta could not be catheterized. Stenting from the radial route was successful in 22 renal arteries in 16 patients. On an intention-to-treat basis 16 of the 19 (84%) were treatable from the radial route. In the 17 patients with radial access technical success was 94% (16 of 17) patients and 91% (21 of 23) of renal arteries. One patient experienced a cerebrovascular event during intervention. Conclusion: Transradial renal artery intervention is technically feasible using low-profile angioplasty balloons and stents.This route offers advantages in renal arteries with a caudal angulation and in patients with diseases or tortuous iliac arteries.

  10. Emergency Percutaneous Coronary Intervention Through the Left Radial Artery is Associated with Less Vascular Complications than Emergency Percutaneous Coronary Intervention Through the Femoral Artery

    PubMed Central

    Qi, Guoqing; Sun, Qi; Xia, Yue; Wei, Liye

    2017-01-01

    OBJECTIVE: To compare the advantages and disadvantages of emergency percutaneous coronary intervention through the left radial artery with those of emergency percutaneous coronary intervention through the femoral artery. METHODS: A total of 206 patients with acute myocardial infarction who required emergency percutaneous coronary intervention and were admitted to our hospital between January 2011 and August 2013 were divided into the following two groups: a group that underwent percutaneous coronary intervention through the left radial artery and a group that underwent percutaneous coronary intervention through the femoral artery. The times required for angiographic catheter and guiding catheter placement, the success rate of the procedure and the incidence of vascular complications in the two groups were observed. RESULTS: There was no significant difference in catheter placement time or the ultimate success rate of the procedure between the two groups. However, the left radial artery group showed a significantly lower incidence of vascular complications than the femoral artery group (p<0.05). CONCLUSION: Emergency percutaneous coronary intervention through the left radial artery is associated with less vascular complications than emergency percutaneous coronary intervention through the femoral artery and is thus potentially advantageous for patients. PMID:28226025

  11. Lateral approach to laparoscopic repair of left diaphragmatic ruptures.

    PubMed

    Goudet, P; Cheynel, N; Ferrand, L; Peschaud, F; Steinmetz, J P; Letourneau, B; Isnardon, J P; Noirot, M T; Poli, L; Freysz, M; Cougard, P

    2001-09-01

    Video-assisted repairs of traumatic diaphragmatic ruptures have been described where thoracoscopy or laparoscopy in the supine position were used. This study aims to validate a new lateral laparoscopic approach for left diaphragmatic repairs. Six consecutive patients were operated on for left diaphragmatic rupture using a lateral approach (Gagner's position). A series of 362 consecutive patients presenting with abdominal or thoracic trauma with or without diaphragmatic rupture over a 2-year period were reviewed retrospectively. Contraindications for immediate or delayed lateral laparoscopic approach were studied. The lateral approach provided complete visibility of the subdiaphragmatic space, easy reduction of herniated organs, easy thoracic inspection and cleaning, the use of low peritoneal pressure, full range of instrumental motion, and rapid diaphragmatic repair. No operative mortality or morbidity was noted. Altogether, 14% to 50% of the patients with diaphragmatic ruptures were candidates for immediate lateral laparoscopic repair. Associated spleen injury in 50% of the cases was the main contraindication. The lateral laparoscopic approach provides better exposure of the diaphragm on the left side and facilitates the diaphragmatic repair especially with a large herniation. Immediate repair is possible in selected cases (14-50%). There is no contraindication in case of delayed diagnosis.

  12. Systematic comparison of the effectiveness of radial artery and saphenous vein or right internal thoracic artery coronary bypass grafts in non-left anterior descending coronary arteries

    PubMed Central

    Hu, Xiang; Zhao, Qiang

    2011-01-01

    Coronary artery bypass grafting surgery is increasingly being carried out on patients with multi-vessel coronary artery disease, but the best grafting candidate for non-left anterior descending coronary arteries is unclear. This research sought to systematically compare the efficacies and safeties of coronary bypass with radial artery and other available grafts. A systematic literature retrieval was performed for all clinical trials comparing the outcomes of coronary artery bypass surgery with radial artery and other grafts in PubMed, EMBASE, and the Cochrane Library. Seven eligible clinical studies, comparing radial artery and great saphenous vein grafts, were found between 1966 and 2010: one prospective non-randomized and six prospective randomized trials. The pooling analysis obtained a relative risk of 0.507 (P<0.05) of graft occlusion in radial arteries compared with great saphenous veins. There was a significantly lower infection rate in arms (i.e., harvest sites for radial arteries) relative to legs (harvest sites for veins), with a pooled relative risk of 0.140 (P<0.05). From the reports on mortality after follow-up ranging from one year to six years, there was no significant difference in mortality between the two graft types (P=0.927). In addition, four cohort controlled trials for radial and right internal thoracic artery grafts were included. The radial graft was associated with less cardiac related events relative to the right internal thoracic artery graft (P=0.014), but with comparable mortality and comparable rates of repeat percutaneous transluminal coronary angioplasty. Subjects with radial arteries seemed to have a lower occlusion rate and a lower graft harvest site infection rate than those with great saphenous veins. Moreover there were fewer cardiac related events with radial arteries relative to the right internal thoracic artery grafts. More studies are needed to confirm these findings concerning the favorable outcomes of coronary artery

  13. Robotic Left Ventricular Assist Device Implantation Using Left Thoracotomy Approach in Patients with Previous Sternotomies.

    PubMed

    Khalpey, Zain; Bin Riaz, Irbaz; Marsh, Katherine M; Ansari, Muhammad Zubair Ahmad; Bilal, Jawad; Cooper, Anthony; Paidy, Samata; Schmitto, Jan D; Smith, Richard; Friedman, Mark; Slepian, Marvin J; Poston, Robert

    2015-01-01

    Left ventricular assist devices (LVADs) are commonly used as either a bridge-to-transplant or a destination therapy. The traditional approach for LVAD implantation is via median sternotomy, but many candidates for this procedure have a history of failed cardiac surgeries and previous sternotomy. Redo sternotomy increases the risk of heart surgery, particularly in the setting of advanced heart failure. Robotics facilitates a less invasive approach to LVAD implantation that circumvents some of the morbidity associated with a redo sternotomy. We compared the outcomes of all patients at our institution who underwent LVAD implantation via either a traditional sternotomy or using robotic assistance. The robotic cohort showed reduced resource utilization including length of hospital stay and use of blood products. As the appropriate candidates become elucidated, robotic assistance may improve the safety and cost-effectiveness of reoperative LVAD surgery.

  14. Case report: congenital dislocation of the radial head –a two-in-one approach

    PubMed Central

    Karuppal, Raju; Marthya, Anwar; Raman, Rajendran V; Somasundaran, Sandhya

    2014-01-01

    Background: Congenital dislocation of the radial head of the elbow is rare. It is genetically transmitted in some cases and is often associated with syndromes, such as Nail-Patella syndrome, antecubital pterygium and ulnar dysplasia. About two thirds are posterior, with the remainder being either anterior (15%) or lateral (15%). The natural history of the condition is that symptoms are relatively benign, with only some limitation of motion and deformity. Treatment either involves early attempts at reconstruction or delayed intervention at skeletal maturity with radial head excision. We evaluated the radiographic and functional results of a two-in-one procedure (radial shortening and open reduction) in the treatment of congenital dislocation of the radial head of an eight year old girl. Objective: To describe a technique for easy reduction and maintenance of normal radiocapitellar joint anatomy in cases of congenital dislocation of the radial head. Method: We have introduced one modification to the Sachar’s method of open reduction by adding radial shortening. This can be described as a ‘two incision approach’ with the first incision for the radial shortening and the second for the open reduction of the radiocapitellar joint. The radial shaft was osteotomised first before we performed the radial head relocation. Then the overlapping part of radial shaft was trimmed. It was stabilized with a transarticular K wire fixation. Results: At one year follow up, the elbow is stable with no valgus or fixed flexion deformity. Supination has increased to 40 degrees from zero degrees. An X-ray showed reformation of the radial head with good congruity of the radiocapitellar joint and correction of the radial bow. Conclusion: As far as the authors are aware, this is the first report of congenital dislocation of the radial head being treated by radial shortening and open reduction of radiocapitellar joint through a two incision approach (two-in-one approach). This paper

  15. Retrograde approach to an ostial left anterior descending chronic total occlusion through a left internal mammary artery graft.

    PubMed

    Hari, Pawan; Kirtane, Ajay J; Bangalore, Sripal

    2016-05-01

    Retrograde approach to chronic total occlusions (CTO) has been described via saphenous vein grafts, septal and epicardial collaterals. We report for the first time a successful retrograde approach to an ostial left anterior descending (LAD) artery CTO through a failed left internal mammary artery (LIMA) to LAD anastamosis. This case demonstrates the technical aspects of using a LIMA conduit as a retrograde approach to CTO. © 2015 Wiley Periodicals, Inc.

  16. Radial left ventricular dyssynchrony by speckle tracking in apical versus non apical right ventricular pacing- evidence of dyssynchrony on medium term follow up

    PubMed Central

    Choudhary, Dinesh; Chaurasia, Amit Kumar; Kumar, S Mahesh; Arulkumar, Ajeet; Thajudeen, Anees; Namboodiri, Narayanan; Sanjay, G; Abhilash, SP; Ajitkumar, VK; JA, Tharakan

    2016-01-01

    Introduction: To study effects of various sites of right ventricular pacing lead implantation on left ventricular function by 2-dimensional (2D) speckle tracking for radial strain and LV dyssynchrony. Methods: This was retrospective prospective study. Fifteen patients each with right ventricular (RV) apical (RV apex and apical septum) and non-apical (mid septal and low right ventricular outflow tract [RVOT]) were programmed to obtain 100% ventricular pacing for evaluation by echo. Location and orientation of lead tip was noted and archived by fluoroscopy. Electrocardiography (ECG) was archived and 2D echo radial dyssynchrony was calculated. Results: The baseline data was similar between two groups. Intraventricular dyssynchrony was significantly more in apical location as compared to non-apical location (radial dyssynchrony: 108.2 ± 50.2 vs. 50.5 ± 24, P < 0.001; septal to posterior wall delay [SLWD] 63.5 ± 27.5 vs. 34 ± 10.7, P < 0.001, SPWD 112.5 ± 58.1 vs. 62.7 ± 12.1, P = 0.003). The left ventricular ejection fraction was decreased more in apical location than non apical location. Interventricular dyssynchrony was more in apical group but was not statistically significant. The QRS duration, QTc and lead thresholds were higher in apical group but not statistically significant. Conclusion: Pacing in non apical location (RV mid septum or low RVOT) is associated with less dyssynchrony by specific measures like 2D radial strain and correlates with better ventricular function in long term. PMID:27069563

  17. Left ventricular radial colour and longitudinal pulsed-wave tissue Doppler echocardiography in 39 healthy domestic pet rabbits.

    PubMed

    Casamian-Sorrosal, Domingo; Saunders, Richard; Browne, William; Elliot, Sarah; Fonfara, Sonja

    2014-10-01

    This paper reports radial colour and longitudinal mitral annulus pulsed-wave tissue Doppler findings in a large cohort of healthy, adult pet rabbits. Thirty-nine rabbits (22 Dwarf Lops, 14 French Lops and three Alaskans) underwent conscious echocardiography. The median age of the rabbits was 22 months and the median weight was 2.8 kg (Dwarf Lop 2.4 kg/French Lop 6.0 kg). Adequate radial colour and longitudinal pulsed-wave tissue Doppler traces were obtained in 100% and 85% of cases, respectively. Most systolic tissue Doppler parameters were significantly higher in French Lops than in Dwarf Lops. Separation of mitral inflow diastolic waves was present in 40% of cases using conventional spectral Doppler and in >60% of cases using pulsed-wave tissue Doppler which could be beneficial when evaluating diastolic function in rabbits. This study can be used as a reference for normal echocardiographic tissue Doppler values for adult rabbits undergoing conscious echocardiography in clinical practice.

  18. Transmesocolic Approach for Left Side Laparoscopic Pyeloplasty: Comparison with Laterocolic Approach in the Initial Learning Period

    PubMed Central

    Han, Hyun Ho; Ham, Won Sik; Kim, Jang Hwan; Choi, Young Deuk; Han, Sang Won; Chung, Byung Ha

    2013-01-01

    Purpose To evaluate the outcome of transmesocolic (TMC) laparoscopic pyeloplasty compared with conventional laterocolic procedure for surgeons with limited experience. Materials and Methods We started laparoscopic pyeloplasty for ureteropelvic junction obstruction in 2009. Since then, 21 patients of left side disease have undergone this surgery in our institution. To access the left ureteropelvic junction, we used the conventional laterocolic approach in 9 patients, while the transmesocolic approach was used in the remaining 12 patients, and perioperative results and follow-up data were then compared. Results The mean operative time using the transmesocolic approach was significantly shorter than the conventional laterocolic approach (242 vs. 308 min, p=0.022). Furthermore, there was no complication or open conversion. Postoperative pain was significantly decreased in the TMC group (2.8 vs. 4.0 points, measured using the visual analogue scale on the first postoperative day, p=0.009). Postoperative complications were encountered in two patients. All patients were symptom-free after 1 year of follow-up, and radiologic success rates for each group were 92 and 89%, respectively. Conclusion Direct exposure of the ureteropelvic junction via the mesocolon saves time during the colon mobilization procedure. The approach is safe and feasible even for surgeons with limited experience, and has success rates similar to those of the conventional laterocolic approach. PMID:23225819

  19. pSnakes: a new radial active contour model and its application in the segmentation of the left ventricle from echocardiographic images.

    PubMed

    de Alexandria, Auzuir Ripardo; Cortez, Paulo César; Bessa, Jessyca Almeida; da Silva Félix, John Hebert; de Abreu, José Sebastião; de Albuquerque, Victor Hugo C

    2014-10-01

    Active contours are image segmentation methods that minimize the total energy of the contour to be segmented. Among the active contour methods, the radial methods have lower computational complexity and can be applied in real time. This work aims to present a new radial active contour technique, called pSnakes, using the 1D Hilbert transform as external energy. The pSnakes method is based on the fact that the beams in ultrasound equipment diverge from a single point of the probe, thus enabling the use of polar coordinates in the segmentation. The control points or nodes of the active contour are obtained in pairs and are called twin nodes. The internal energies as well as the external one, Hilbertian energy, are redefined. The results showed that pSnakes can be used in image segmentation of short-axis echocardiogram images and that they were effective in image segmentation of the left ventricle. The echo-cardiologist's golden standard showed that the pSnakes was the best method when compared with other methods. The main contributions of this work are the use of pSnakes and Hilbertian energy, as the external energy, in image segmentation. The Hilbertian energy is calculated by the 1D Hilbert transform. Compared with traditional methods, the pSnakes method is more suitable for ultrasound images because it is not affected by variations in image contrast, such as noise. The experimental results obtained by the left ventricle segmentation of echocardiographic images demonstrated the advantages of the proposed model. The results presented in this paper are justified due to an improved performance of the Hilbert energy in the presence of speckle noise.

  20. Ovariectomy by left flank approach in prepubertal Nelore (Bos indicus) heifers

    PubMed Central

    Peiró, Juliana R.; Nogueira, Geison M.; Nogueira, Guilherme P.; Perri, Silvia H.V.; Cardoso, Daniel

    2009-01-01

    The main objective of this study was to evaluate a recumbent left flank approach to bilateral ovariectomy in prepubertal heifers and to develop an optimal surgical technique for this procedure. Both ovaries were removed from 6 Nelore heifers by left flank approach without any complications, except in 1 heifer, which was believed to have had only 1 ovary based on ultrasound and exploration during surgery, but was later found to have a remaining functional ovary. Ovariectomy via left flank approach in recumbent prepubertal heifers is feasible and technically easy. This procedure does not involve special instrumentation and, despite the invasive approach, it allows optimal visualization of the ovaries and uterus. PMID:19794897

  1. The Current Approach to Diagnosis and Management of Left Ventricular Noncompaction Cardiomyopathy: Review of the Literature

    PubMed Central

    Bennett, Courtney E.; Freudenberger, Ronald

    2016-01-01

    Isolated left ventricular noncompaction (LVNC) is a genetic cardiomyopathy characterized by prominent ventricular trabeculations and deep intertrabecular recesses, or sinusoids, in communication with the left ventricular cavity. The low prevalence of patients with this cardiomyopathy presents a unique challenge for large, prospective trials to assess its pathogenesis, management, and outcomes. In this paper we review the embryology and genetics of LVNC, the diagnostic approach, and propose a management approach based on the current literature available. PMID:26881173

  2. Successful Angioplasty of Left Vertebral Artery and Right Subclavian Artery Via Retrograde Approach

    PubMed Central

    Namazi, Mohammad Hasan; Momenizadeh, Amir; Dousti, Amir; Naderian, Mohammadreza

    2017-01-01

    We describe a 77-year-old male who had right upper limb ischemic symptoms and history of unsuccessful right subclavian artery angioplasty. According to ultrasound findings, upper limb angiography was performed which confirmed stenosis of the left vertebral and right subclavian arteries. Percutaneous angioplasty and stenting of left vertebral and right subclavian arteries were performed in two separate sessions. Retrograde approach was scheduled for right subclavian artery angioplasty which is challenging due to potential risks to adjacent vertebral artery. This case reports underscores that percutaneous approaches may be preferential given their confirmed long-term efficacy and lower morbidity.

  3. [Artificial Inversion of the Left-Right Visceral Asymmetry in Vertebrates: Conceptual Approaches and Experimental Solutions].

    PubMed

    Truleva, A S; Malashichev, E B; Ermakov, A S

    2015-01-01

    Externally, vertebrates are bilaterally symmetrical; however, left-right asymmetry is observed in the structure of their internal organs and systems of organs (circulatory, digestive, and respiratory). In addition to the asymmetry of internal organs (visceral), there is also functional (i.e., asymmetrical functioning of organs on the left and right sides of the body) and behavioral asymmetry. The question of a possible association between different types of asymmetry is still open. The study of the mechanisms of such association, in addition to the fundamental interest, has important applications for biomedicine, primarily for the understanding of the brain functioning in health and disease and for the development of methods of treatment of certain mental diseases, such as schizophrenia and autism, for which the disturbance of left-right asymmetry of the brain was shown. To study the deep association between different types of asymmetry, it is necessary to obtain adequate animal models (primarily animals with inverted visceral organs, situs inversus totalis). There are two main possible approaches to obtaining such model organisms: mutagenesis followed by selection of mutant strains with mutations in the genes that affect the formation of the left-right visceral asymmetry and experimental obtaining of animals with inverted internal organs. This review focuses on the second approach. We describe the theoretical models for establishing left-right asymmetry and possible experimental approaches to obtaining animals with inverted internal organs.

  4. The radial basis function finite collocation approach for capturing sharp fronts in time dependent advection problems

    NASA Astrophysics Data System (ADS)

    Stevens, D.; Power, H.

    2015-10-01

    We propose a node-based local meshless method for advective transport problems that is capable of operating on centrally defined stencils and is suitable for shock-capturing purposes. High spatial convergence rates can be achieved; in excess of eighth-order in some cases. Strongly-varying smooth profiles may be captured at infinite Péclet number without instability, and for discontinuous profiles the solution exhibits neutrally stable oscillations that can be damped by introducing a small artificial diffusion parameter, allowing a good approximation to the shock-front to be maintained for long travel times without introducing spurious oscillations. The proposed method is based on local collocation with radial basis functions (RBFs) in a "finite collocation" configuration. In this approach the PDE governing and boundary equations are enforced directly within the local RBF collocation systems, rather than being reconstructed from fixed interpolating functions as is typical of finite difference, finite volume or finite element methods. In this way the interpolating basis functions naturally incorporate information from the governing PDE, including the strength and direction of the convective velocity field. By using these PDE-enhanced interpolating functions an "implicit upwinding" effect is achieved, whereby the flow of information naturally respects the specifics of the local convective field. This implicit upwinding effect allows high-convergence solutions to be obtained on centred stencils for advection problems. The method is formulated using a high-convergence implicit timestepping algorithm based on Richardson extrapolation. The spatial and temporal convergence of the proposed approach is demonstrated using smooth functions with large gradients. The capture of discontinuities is then investigated, showing how the addition of a dynamic stabilisation parameter can damp the neutrally stable oscillations with limited smearing of the shock front.

  5. Simultaneous resection of left atrial myxoma and esophageal carcinoma via right thoraco-abdominal approach

    PubMed Central

    Ni, Buqing; Lu, Xiaohu; Gong, Qixing

    2016-01-01

    Concomitant occurrence of atrial myxoma and esophageal carcinoma is an extremely rare entity. Here we present two cases of synchronously suffered left atrial myxoma and esophageal carcinoma. Both patients underwent simultaneous resection of two tumors via the right thoraco-abdominal approach and recovered well. PMID:27499990

  6. Assessing assay agreement estimation for multiple left-censored data: a multiple imputation approach.

    PubMed

    Lapidus, Nathanael; Chevret, Sylvie; Resche-Rigon, Matthieu

    2014-12-30

    Agreement between two assays is usually based on the concordance correlation coefficient (CCC), estimated from the means, standard deviations, and correlation coefficient of these assays. However, such data will often suffer from left-censoring because of lower limits of detection of these assays. To handle such data, we propose to extend a multiple imputation approach by chained equations (MICE) developed in a close setting of one left-censored assay. The performance of this two-step approach is compared with that of a previously published maximum likelihood estimation through a simulation study. Results show close estimates of the CCC by both methods, although the coverage is improved by our MICE proposal. An application to cytomegalovirus quantification data is provided.

  7. Breakdown of Burton Prim Slichter approach and lateral solute segregation in radially converging flows

    NASA Astrophysics Data System (ADS)

    Priede, J.; Gerbeth, G.

    2005-11-01

    A theoretical study is presented of the effect of a radially converging melt flow, which is directed away from the solidification front, on the radial solute segregation in simple solidification models. We show that the classical Burton-Prim-Slichter (BPS) solution describing the effect of a diverging flow on the solute incorporation into the solidifying material breaks down for the flows converging along the solidification front. The breakdown is caused by a divergence of the integral defining the effective boundary layer thickness which is the basic concept of the BPS theory. Although such a divergence can formally be avoided by restricting the axial extension of the melt to a layer of finite height, radially uniform solute distributions are possible only for weak melt flows with an axial velocity away from the solidification front comparable to the growth rate. There is a critical melt velocity for each growth rate at which the solution passes through a singularity and becomes physically inconsistent for stronger melt flows. To resolve these inconsistencies we consider a solidification front presented by a disk of finite radius R0 subject to a strong converging melt flow and obtain an analytic solution showing that the radial solute concentration depends on the radius r as ˜ln(R0/r) and ˜ln(R0/r) close to the rim and at large distances from it. The logarithmic increase of concentration is limited in the vicinity of the symmetry axis by the diffusion becoming effective at a distance comparable to the characteristic thickness of the solute boundary layer. The converging flow causes a solute pile-up forming a logarithmic concentration peak at the symmetry axis which might be an undesirable feature for crystal growth processes.

  8. Influence of radial and tangential anisotropy components in single wall magnetic nanotubes. A Monte Carlo approach

    NASA Astrophysics Data System (ADS)

    Agudelo-Giraldo, J. D.; Morales-Rojas, S.; Hurtado-Marín, V. A.; Restrepo-Parra, E.

    2017-01-01

    Magnetic behaviour of nanotubes with square cell has been studied by the Monte Carlo Method, under the Metropolis algorithm and Heisenberg model. The Hamiltonian used includes nearest neighbour exchange interaction and radial and tangential direction for uniaxial anisotropy. Periodic boundary conditions were implemented at the sample's edges. Simulations were carried out varying the nanotube's diameter by changing the number of magnetic moments per ring and anisotropy values. Two transition temperatures were identified corresponding to states where moments were aligned as either ferromagnetic type or anisotropy direction. At low temperatures and low anisotropy values, the system exhibited a ferromagnetic alignment; as the anisotropy was increased, and continued in the low temperature range, spins were aligned in the anisotropy (radial or tangential) direction. As the temperature was increased, spins were reoriented in the ferromagnetic direction, generating a radial (tangential) anisotropy to ferromagnetic transition temperature. When the temperature continued increasing, the system transited toward the paramagnetic phase, appearing a ferromagnetic to paramagnetic transition phase temperature. In several cases studied here, between these two transition temperatures (anisotropy to ferromagnetic and ferromagnetic to paramagnetic transition phases), the magnetization of the system exhibited instabilities. These instabilities are caused because of the influence of the anisotropy values and the diameter of the nanotubes on the magnetic domains formation. As a consequence, there exist anisotropy values and diameters where metastable states were formed.

  9. Left atrial appendage exclusion for prevention of stroke in atrial fibrillation: review of minimally invasive approaches.

    PubMed

    Moss, Joshua D

    2014-02-01

    Stroke prevention is of vital importance in the management of atrial fibrillation (AF), though the proven strategy of systemic anticoagulation for thromboembolic prophylaxis is underutilized for a variety of reasons. The left atrial appendage (LAA) has long been suspected as the principal source of arterial emboli, particularly in nonvalvular AF, and a variety of techniques for its exclusion from the circulation have been developed. This review highlights the history of the LAA as a target of intervention, and the parallel advances in three minimally invasive strategies for its exclusion: percutaneous occlusion of the LAA orifice from within the left atrium, closed-chest ligation via a percutaneous pericardial approach, and minimally invasive thoracoscopic surgery. While further study is necessary, available evidence suggests that effective LAA exclusion is becoming a viable alternative to anticoagulation for stroke prevention in nonvalvular AF.

  10. Balloon-Assisted Tracking to Overcome Radial Spasm during Transradial Coronary Angiography: A Case Report

    PubMed Central

    Verouden, N. J. W.; Kiemeneij, F.

    2014-01-01

    Spasm of the radial artery is the most important cause of failure to perform coronary angiography via the transradial approach. Spasmolytic cocktail may prevent radial artery spasm but is relatively contraindicated in patients with aortic stenosis or diminished left ventricular function. In this case report we describe a recently published technique to overcome severe radial spasm during transradial coronary angiography in a patient with moderate aortic valve stenosis. PMID:24826306

  11. Balloon-Assisted Tracking to Overcome Radial Spasm during Transradial Coronary Angiography: A Case Report.

    PubMed

    Verouden, N J W; Kiemeneij, F

    2014-01-01

    Spasm of the radial artery is the most important cause of failure to perform coronary angiography via the transradial approach. Spasmolytic cocktail may prevent radial artery spasm but is relatively contraindicated in patients with aortic stenosis or diminished left ventricular function. In this case report we describe a recently published technique to overcome severe radial spasm during transradial coronary angiography in a patient with moderate aortic valve stenosis.

  12. Optimization of global model composed of radial basis functions using the term-ranking approach

    SciTech Connect

    Cai, Peng; Tao, Chao Liu, Xiao-Jun

    2014-03-15

    A term-ranking method is put forward to optimize the global model composed of radial basis functions to improve the predictability of the model. The effectiveness of the proposed method is examined by numerical simulation and experimental data. Numerical simulations indicate that this method can significantly lengthen the prediction time and decrease the Bayesian information criterion of the model. The application to real voice signal shows that the optimized global model can capture more predictable component in chaos-like voice data and simultaneously reduce the predictable component (periodic pitch) in the residual signal.

  13. Advantages of a workbench reshaped AR1 mod catheter for right coronary angiography by right radial approach.

    PubMed

    Baldi, Cesare; Mirra, Marco; Di Maio, Marco; Attisano, Tiziana; Di Muro, Michele Roberto; Vigorito, Francesco; Farina, Rosario; Polito, Maria Vincenza; Giudice, Pietro; Piscione, Federico

    2014-03-01

    Transradial approach in cardiac catheterization is increasing. In daily practice, coronary angiography via radial artery is usually performed by using catheters designed for femoral approach. The aim of this study was to evaluate advantages in the use of a workbench reshaped AR1 mod catheter, in terms of procedural duration time, number of catheters per procedure, fluoroscopy time, contrast agent administered volume, images quality and costs. Two hundred patients, submitted to coronary angiography via right radial artery in our institution, have been retrospectively reviewed. Patients have been divided in two groups, depending on whether a workbench reshaped Cordis Amplatz AR1 mod catheter (rAR1 mod), or catheters in their original shape (OC) have been employed. In the rAR1 mod group (100 patients) a lower number of catheters per procedure (1.07 ± 0.25 vs. 1.47 ± 1.65; p < 0.001), a more frequent right coronary selective engagement (76.76% vs. 53.12%; p < 0.001), a smaller amount of contrast agent (63.02 ± 27.77 vs. 80.85 ± 29.22 ml, p < 0.001), a reduced fluoroscopy and global procedural time (4.19 ± 2.91 vs. 5.69 ± 3.85 min, p = 0.004; and 34.58 ± 17.05 vs. 42.58 ± 17.26 min, p = 0.001, respectively) were observed. According to our experience, when right coronary angiography via right radial approach is performed, the utilization of rAR1 mod catheter correlates with multiple advantages in terms of procedural parameters.

  14. Radial Erosion

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The ejecta surrounding the crater (off image to the left) in this image has undergone significant erosion by the wind. The wind has stripped the surface features from the ejecta and has started to winnow away the ejecta blanket. Near the margin of the ejecta the wind is eroding along a radial pattern -- taking advantage of radial emplacement. Note the steep margin of the ejecta blanket. Most, if not all, of the fine ejecta material has been removed and the wind in now working on the more massive continuous ejecta blanket.

    Image information: VIS instrument. Latitude 12.5, Longitude 197.4 East (162.6 West). 37 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  15. On the applicability of the standard approaches for evaluating a neoclassical radial electric field in a tokamak edge region

    DOE PAGES

    Dorf, M. A.; Cohen, R. H.; Simakov, A. N.; ...

    2013-08-27

    The use of the standard approaches for evaluating a neoclassical radial electric field Er, i.e., the Ampere (or gyro-Poisson) equation, requires accurate calculation of the difference between the gyroaveraged electron and ion particle fluxes (or densities). In the core of a tokamak, the nontrivial difference appears only in high-order corrections to a local Maxwellian distribution due to the intrinsic ambipolarity of particle transport. The evaluation of such high-order corrections may be inconsistent with the accuracy of the standard long wavelength gyrokinetic equation (GKE), thus imposing limitations on the applicability of the standard approaches. However, in the edge of a tokamak,more » charge-exchange collisions with neutrals and prompt ion orbit losses can drive non-intrinsically ambipolar particle fluxes for which a nontrivial (Er-dependent) difference between the electron and ion fluxes appears already in a low order and can be accurately predicted by the long wavelength GKE. As a result, the parameter regimes where the radial electric field dynamics in the tokamak edge region is dominated by the non-intrinsically ambipolar processes, thus allowing for the use of the standard approaches, are discussed.« less

  16. On the applicability of the standard approaches for evaluating a neoclassical radial electric field in a tokamak edge region

    SciTech Connect

    Dorf, M. A.; Cohen, R. H.; Simakov, A. N.; Joseph, I.

    2013-08-27

    The use of the standard approaches for evaluating a neoclassical radial electric field Er, i.e., the Ampere (or gyro-Poisson) equation, requires accurate calculation of the difference between the gyroaveraged electron and ion particle fluxes (or densities). In the core of a tokamak, the nontrivial difference appears only in high-order corrections to a local Maxwellian distribution due to the intrinsic ambipolarity of particle transport. The evaluation of such high-order corrections may be inconsistent with the accuracy of the standard long wavelength gyrokinetic equation (GKE), thus imposing limitations on the applicability of the standard approaches. However, in the edge of a tokamak, charge-exchange collisions with neutrals and prompt ion orbit losses can drive non-intrinsically ambipolar particle fluxes for which a nontrivial (Er-dependent) difference between the electron and ion fluxes appears already in a low order and can be accurately predicted by the long wavelength GKE. As a result, the parameter regimes where the radial electric field dynamics in the tokamak edge region is dominated by the non-intrinsically ambipolar processes, thus allowing for the use of the standard approaches, are discussed.

  17. KANTBP 2.0: New version of a program for computing energy levels, reaction matrix and radial wave functions in the coupled-channel hyperspherical adiabatic approach

    NASA Astrophysics Data System (ADS)

    Chuluunbaatar, O.; Gusev, A. A.; Vinitsky, S. I.; Abrashkevich, A. G.

    2008-11-01

    A FORTRAN 77 program for calculating energy values, reaction matrix and corresponding radial wave functions in a coupled-channel approximation of the hyperspherical adiabatic approach is presented. In this approach, a multi-dimensional Schrödinger equation is reduced to a system of the coupled second-order ordinary differential equations on a finite interval with homogeneous boundary conditions: (i) the Dirichlet, Neumann and third type at the left and right boundary points for continuous spectrum problem, (ii) the Dirichlet and Neumann type conditions at left boundary point and Dirichlet, Neumann and third type at the right boundary point for the discrete spectrum problem. The resulting system of radial equations containing the potential matrix elements and first-derivative coupling terms is solved using high-order accuracy approximations of the finite element method. As a test desk, the program is applied to the calculation of the reaction matrix and radial wave functions for 3D-model of a hydrogen-like atom in a homogeneous magnetic field. This version extends the previous version 1.0 of the KANTBP program [O. Chuluunbaatar, A.A. Gusev, A.G. Abrashkevich, A. Amaya-Tapia, M.S. Kaschiev, S.Y. Larsen, S.I. Vinitsky, Comput. Phys. Commun. 177 (2007) 649-675]. Program summaryProgram title: KANTBP Catalogue identifier: ADZH_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADZH_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 20 403 No. of bytes in distributed program, including test data, etc.: 147 563 Distribution format: tar.gz Programming language: FORTRAN 77 Computer: Intel Xeon EM64T, Alpha 21264A, AMD Athlon MP, Pentium IV Xeon, Opteron 248, Intel Pentium IV Operating system: OC Linux, Unix AIX 5.3, SunOS 5.8, Solaris, Windows XP RAM: This depends on the

  18. [Evaluation of superior transseptal approach for the removal of left atrial myxoma].

    PubMed

    Kunitomo, R; Okamoto, K; Utoh, J; Nishimura, K; Muranaka, T; Tsurusaki, S; Hagio, K; Kitamura, N

    2001-03-01

    We compared the operative outcomes among 14 patients who underwent the removal of left atrial myxoma with four different approaches; right lateral (n = 2), transseptal bi-atrial (Dubost, n = 4), conventional transseptal (n = 4) and superior transseptal approach (STA, n = 4). Concomitant operations were performed in 4 cases (CABG, two; aortic valvuloplasty, one; mitral valve replacement, one), and two out of 4 cases were in the STA group. The mean operation, cardiopulmonary bypass and aortic cross-clamp times were shorter in the STA group compared to the other three group. The total amount of postoperative drain discharge and the peak value of creatine kinase were also lower in the STA group compared to the other three groups. Among the patients in sinus rhythm before operation, the use of STA was associated with a greater incidence (100%) of postoperative atrial fibrillation or junctional rhythm. These rhythm disturbances were temporary, and all returned to sinus rhythms during hospital stay. We conclude that STA is an excellent approach with a nice surgical view to expose and remove the left atrial myxoma.

  19. Electrophysiologic testing guided risk stratification approach for sudden cardiac death beyond the left ventricular ejection fraction.

    PubMed

    Gatzoulis, Konstantinos A; Tsiachris, Dimitris; Arsenos, Petros; Tousoulis, Dimitris

    2016-01-26

    Sudden cardiac death threats ischaemic and dilated cardiomyopathy patients. Anti- arrhythmic protection may be provided to these patients with implanted cardiac defibrillators (ICD), after an efficient risk stratification approach. The proposed risk stratifier of an impaired left ventricular ejection fraction has limited sensitivity meaning that a significant number of victims will remain undetectable by this risk stratification approach because they have a preserved left ventricular systolic function. Current risk stratification strategies focus on combinations of non invasive methods like T wave alternans, late potentials, heart rate turbulence, deceleration capacity and others, with invasive methods like the electrophysiologic study. In the presence of an electrically impaired substrate with formed post myocardial infarction fibrotic zones, programmed ventricular stimulation provides important prognostic information for the selection of the patients expected to benefit from an ICD implantation, while due to its high negative predictive value, patients at low risk level may also be detected. Clustering evidence from different research groups and electrophysiologic labs support an electrophysiologic testing guided risk stratification approach for sudden cardiac death.

  20. Comparing estimation approaches for the illness-death model under left truncation and right censoring.

    PubMed

    Vakulenko-Lagun, Bella; Mandel, Micha

    2016-04-30

    Left-truncated data arise when lifetimes are observed only if they are larger than independent truncation times. For example, in a cross-sectional sampling, only individuals who live long enough to be present on the sampling day are observed. There are several ways to perform statistical inference under this setting. One can do the following: (i) use an unconditional approach, (ii) condition on the value of the truncation variable, or (iii) condition on all the history up to the time of truncation. The latter two approaches are equivalent when analyzing univariate survival outcomes but differ under the multi-state framework. In this paper, we consider the illness-death model and compare between the three estimation approaches in a parametric regression framework. We show that approach (ii) is more efficient than the standard approach (iii), although it requires more computational effort. Approach (i) is the most efficient approach, but it requires knowledge on the distribution of the truncation variable and hence is less robust. The methods are compared using a theoretical example and simulations and are applied to intensive care units data collected in a cross-sectional design, where the illness state corresponds to a bloodstream infection.

  1. Initial Comparison of Direct and Legacy Modeling Approaches for Radial Core Expansion Analysis

    SciTech Connect

    Shemon, Emily R.

    2016-10-10

    Radial core expansion in sodium-cooled fast reactors provides an important reactivity feedback effect. As the reactor power increases due to normal start up conditions or accident scenarios, the core and surrounding materials heat up, causing both grid plate expansion and bowing of the assembly ducts. When the core restraint system is designed correctly, the resulting structural deformations introduce negative reactivity which decreases the reactor power. Historically, an indirect procedure has been used to estimate the reactivity feedback due to structural deformation which relies upon perturbation theory and coupling legacy physics codes with limited geometry capabilities. With advancements in modeling and simulation, radial core expansion phenomena can now be modeled directly, providing an assessment of the accuracy of the reactivity feedback coefficients generated by indirect legacy methods. Recently a new capability was added to the PROTEUS-SN unstructured geometry neutron transport solver to analyze deformed meshes quickly and directly. By supplying the deformed mesh in addition to the base configuration input files, PROTEUS-SN automatically processes material adjustments including calculation of region densities to conserve mass, calculation of isotopic densities according to material models (for example, sodium density as a function of temperature), and subsequent re-homogenization of materials. To verify the new capability of directly simulating deformed meshes, PROTEUS-SN was used to compute reactivity feedback for a series of contrived yet representative deformed configurations for the Advanced Burner Test Reactor design. The indirect legacy procedure was also performed to generate reactivity feedback coefficients for the same deformed configurations. Interestingly, the legacy procedure consistently overestimated reactivity feedbacks by 35% compared to direct simulations by PROTEUS-SN. This overestimation indicates that the legacy procedures are in fact

  2. Distributed Generators Allocation in Radial Distribution Systems with Load Growth using Loss Sensitivity Approach

    NASA Astrophysics Data System (ADS)

    Kumar, Ashwani; Vijay Babu, P.; Murty, V. V. S. N.

    2016-07-01

    Rapidly increasing electricity demands and capacity shortage of transmission and distribution facilities are the main driving forces for the growth of distributed generation (DG) integration in power grids. One of the reasons for choosing a DG is its ability to support voltage in a distribution system. Selection of effective DG characteristics and DG parameters is a significant concern of distribution system planners to obtain maximum potential benefits from the DG unit. The objective of the paper is to reduce the power losses and improve the voltage profile of the radial distribution system with optimal allocation of the multiple DG in the system. The main contribution in this paper is (i) combined power loss sensitivity (CPLS) based method for multiple DG locations, (ii) determination of optimal sizes for multiple DG units at unity and lagging power factor, (iii) impact of DG installed at optimal, that is, combined load power factor on the system performance, (iv) impact of load growth on optimal DG planning, (v) Impact of DG integration in distribution systems on voltage stability index, (vi) Economic and technical Impact of DG integration in the distribution systems. The load growth factor has been considered in the study which is essential for planning and expansion of the existing systems. The technical and economic aspects are investigated in terms of improvement in voltage profile, reduction in total power losses, cost of energy loss, cost of power obtained from DG, cost of power intake from the substation, and savings in cost of energy loss. The results are obtained on IEEE 69-bus radial distribution systems and also compared with other existing methods.

  3. Energy efficiency in Spanish wastewater treatment plants: a non-radial DEA approach.

    PubMed

    Hernández-Sancho, F; Molinos-Senante, M; Sala-Garrido, R

    2011-06-15

    Wastewater treatment plants (WWTPs) are energy-intensive facilities. Thus, reducing their carbon footprint is particularly important, both economically and environmentally. Knowing the real operating energy efficiency of WWTPs is the starting point for any energy-saving initiative. In this article, we applied a non-radial Data Envelopment Analysis (DEA) methodology to calculate energy efficiency indices for sampling of WWTPs located in Spain. In a second stage analysis, we examined the operating variables contributing to differences in energy efficiency among plants. It is verified that energy efficiencies of the analyzed WWTPs were quite low, with only 10% of them being efficient. We found that plant size, quantity of organic matter removed, and type of bioreactor aeration were significant variables in explaining energy efficiency differences. In contrast, age of the plant was not a determining factor in energy consumption. Lastly, we quantified the potential savings, both in economic terms and in terms of CO(2) emissions, that could be expected from an improvement in energy efficiency of WWTPs.

  4. Longitudinal gradient coils with enhanced radial uniformity in restricted diameter: Single-current and multiple-current approaches

    NASA Astrophysics Data System (ADS)

    Romero, Javier A.; Domínguez, Gabriela A.; Anoardo, Esteban

    2017-03-01

    An important requirement for a gradient coil is that the uniformity of the generated magnetic field gradient should be maximal within the active volume of the coil. For a cylindrical geometry, the radial uniformity of the gradient turns critic, particularly in cases where the gradient-unit has to be designed to fit into the inner bore of a compact magnet of reduced dimensions, like those typically used in fast-field-cycling NMR. In this paper we present two practical solutions aimed to fulfill this requirement. We propose a matrix-inversion optimization algorithm based on the Biot-Savart law, that using a proper cost function, allows maximizing the uniformity of the gradient and power efficiency. The used methodology and the simulation code were validated in a single-current design, by comparing the computer simulated field map with the experimental data measured in a real prototype. After comparing the obtained results with the target field approach, a multiple-element coil driven by independent current sources is discussed, and a real prototype evaluated. Opposed equispaced independent windings are connected in pairs conforming an arrangement of independent anti-Helmholtz units. This last coil seizes 80% of its radial dimension with a gradient uniformity better than 5%. The design also provides an adaptable region of uniformity along with adjustable coil efficiency.

  5. Longitudinal gradient coils with enhanced radial uniformity in restricted diameter: Single-current and multiple-current approaches.

    PubMed

    Romero, Javier A; Domínguez, Gabriela A; Anoardo, Esteban

    2017-03-01

    An important requirement for a gradient coil is that the uniformity of the generated magnetic field gradient should be maximal within the active volume of the coil. For a cylindrical geometry, the radial uniformity of the gradient turns critic, particularly in cases where the gradient-unit has to be designed to fit into the inner bore of a compact magnet of reduced dimensions, like those typically used in fast-field-cycling NMR. In this paper we present two practical solutions aimed to fulfill this requirement. We propose a matrix-inversion optimization algorithm based on the Biot-Savart law, that using a proper cost function, allows maximizing the uniformity of the gradient and power efficiency. The used methodology and the simulation code were validated in a single-current design, by comparing the computer simulated field map with the experimental data measured in a real prototype. After comparing the obtained results with the target field approach, a multiple-element coil driven by independent current sources is discussed, and a real prototype evaluated. Opposed equispaced independent windings are connected in pairs conforming an arrangement of independent anti-Helmholtz units. This last coil seizes 80% of its radial dimension with a gradient uniformity better than 5%. The design also provides an adaptable region of uniformity along with adjustable coil efficiency.

  6. Discrimination of Venezuelan spirituous beverages by a trace element-radial basis neural network approach.

    PubMed

    Hernández-Caraballo, Edwin A; Avila de Hernández, Rita M; Rivas-Echeverría, Francklin; Capote-Luna, Tarcisio

    2008-01-15

    Radial basis neural networks (RBNNs) were developed and evaluated for discrimination of specimens of 'aguardiente de Cocuy', a spirituous beverage produced in the northwestern region of Venezuela. The beverage is distilled from the must of Agave cocui Trelease in an artisanship fashion with little quality control. Forty specimens, with known concentrations of copper, iron, and zinc, were used in this study. The specimens were previously collected in various locations around Sucre Municipality (Falcón State) and Urdaneta Municipality (Lara State). The normalized concentrations of these elements served as indirect descriptors of origin (input data). They were presented to the neural networks through 1-3 input nodes in seven different combinations. In addition, two categories (two collection sites) and four categories (two collection sites+two manufacturing conditions) were designated as output data, in order to assess the impact of such selection on the discrimination performance. The overall performance of the four-category RBNNs was as follows (the input data is indicated in parentheses): (Cu-Fe)>(Cu-Zn)>(Cu)>(Zn)>(Fe-Zn)>(Cu-Fe-Zn)>(Fe). In this case, the highest percentage of correct hits was 82.5%. For the two-category RBNNs, the performance decreased as indicated below: (Cu)>(Cu-Fe)>(Cu-Zn)>(Fe-Zn)>(Zn) approximately (Cu-Fe-Zn)>(Fe). The reduction in the number of categories led to an increase in the discrimination performance of all the RBNNs, the best of which was 90.0%. The possibility of discriminating specimens of 'aguardiente de Cocuy' with such an accuracy, based on a single-element determination, is particularly attractive as it would result in a reduction of analysis' costs and laboratory's response time.

  7. Electrical approach to improve left ventricular activation during right ventricle stimulation.

    PubMed

    Bonomini, María Paula; Ortega, Daniel F; Barja, Luis D; Mangani, Nicolasa; Paolucci, Analía; Logarzo, Emilio

    2017-01-01

    Coronary sinus mapping is commonly used to evaluate left atrial activation. Herein, we propose to use it to assess which right ventricular pacing modality produces the shortest left ventricular activation times (R-LVtime) and the narrowest QRS widths. Three study groups were defined: 54 controls without intraventricular conduction disturbances; 15 patients with left bundle branch block, and other 15 with right bundle branch block. Left ventricular activation times and QRS widths were evaluated among groups under sinus rhythm, right ventricular apex, right ventricular outflow tract and high output septal zone (SEPHO). Left ventricular activation time was measured as the time elapsed from the surface QRS onset to the most distal left ventricular deflection recorded at coronary sinus. During the above stimulation modalities, coronary sinus mapping reproduced electrical differences that followed mechanical differences measured by tissue doppler imaging. Surprisingly, 33% of the patients with left bundle branch block displayed an early left ventricular activation time, suggesting that these patients would not benefit from resynchronization therapy. SEPHO improved QRS widths and left ventricular activation times in all groups, especially in patients with left bundle branch block, in whom these variables became similar to controls. Left ventricular activation time could be useful to search the optimum pacing site and would also enable detection of non-responders to cardiac resynchronization therapy. Finally, SEPHO resulted the best pacing modality, because it narrowed QRS-complexes and shortened left ventricular activations of patients with left bundle branch block and preserved the physiological depolarization of controls.

  8. A bio-inspired approach for the reduction of left ventricular workload.

    PubMed

    Pahlevan, Niema M; Gharib, Morteza

    2014-01-01

    Previous studies have demonstrated the existence of optimization criteria in the design and development of mammalians cardiovascular systems. Similarities in mammalian arterial wave reflection suggest there are certain design criteria for the optimization of arterial wave dynamics. Inspired by these natural optimization criteria, we investigated the feasibility of optimizing the aortic waves by modifying wave reflection sites. A hydraulic model that has physical and dynamical properties similar to a human aorta and left ventricle was used for a series of in-vitro experiments. The results indicate that placing an artificial reflection site (a ring) at a specific location along the aorta may create a constructive wave dynamic that could reduce LV pulsatile workload. This simple bio-inspired approach may have important implications for the future of treatment strategies for diseased aorta.

  9. Multiscale approaches to protein-mediated interactions between membranes—relating microscopic and macroscopic dynamics in radially growing adhesions

    NASA Astrophysics Data System (ADS)

    Bihr, Timo; Seifert, Udo; Smith, Ana-Sunčana

    2015-08-01

    Macromolecular complexation leading to coupling of two or more cellular membranes is a crucial step in a number of biological functions of the cell. While other mechanisms may also play a role, adhesion always involves the fluctuations of deformable membranes, the diffusion of proteins and the molecular binding and unbinding. Because these stochastic processes couple over a multitude of time and length scales, theoretical modeling of membrane adhesion has been a major challenge. Here we present an effective Monte Carlo scheme within which the effects of the membrane are integrated into local rates for molecular recognition. The latter step in the Monte Carlo approach enables us to simulate the nucleation and growth of adhesion domains within a system of the size of a cell for tens of seconds without loss of accuracy, as shown by comparison to 106 times more expensive Langevin simulations. To perform this validation, the Langevin approach was augmented to simulate diffusion of proteins explicitly, together with reaction kinetics and membrane dynamics. We use the Monte Carlo scheme to gain deeper insight to the experimentally observed radial growth of micron sized adhesion domains, and connect the effective rate with which the domain is growing to the underlying microscopic events. We thus demonstrate that our technique yields detailed information about protein transport and complexation in membranes, which is a fundamental step toward understanding even more complex membrane interactions in the cellular context.

  10. A semi-analytical approach for calculating the equilibrium structure and radial breathing mode frequency of single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Gong, J.; Thompson, L.; Li, G.

    2016-12-01

    A semi-analytical model for determining the equilibrium configuration and the radial breathing mode (RBM) frequency of single-wall carbon nanotubes (CNTs) is presented. By taking advantage of the symmetry characteristics, a CNT structure is represented by five independent variables. A line search optimization procedure is employed to determine the equilibrium values of these variables by minimizing the potential energy. With the equilibrium configuration obtained, the semi-analytical model enables an efficient calculation of the RBM frequency of the CNTs. The radius and radial breathing mode frequency results obtained from the semi-analytical approach are compared with those from molecular dynamics (MD) and ab initio calculations. The results demonstrate that the semi-analytical approach offers an efficient and accurate way to determine the equilibrium structure and radial breathing mode frequency of CNTs.

  11. A restricted branch and bound approach for setting the left turn phase sequences in signalized networks

    SciTech Connect

    Pillai, R.S.; Rathi, A.K.; Cohen, S.

    1994-07-01

    The main objective of synchronized signal timing is to keep traffic moving along arterial in platoons throughout the signal system by proper setting of left turn phase sequence at signals along the arterials/networks. The synchronization of traffic signals located along the urban/suburban arterials in metropolitan areas is perhaps one of the most cost-effective method for improving traffic flow along these streets. The popular technique for solving this problem formulates it as a mixed integer linear program and used Land and Powell branch and bound search to arrive at the optimal solution. The computation time tends to be excessive for realistic multiarterial network problems due to the exhaustive nature of the branch and bound search technique. Furthermore, the Land and Powell branch and bound code is known to be numerically unstable, which results in suboptimal solutions for network problems with a range on the cycle time variable. This paper presents the development of a fast and numerically stable heuristic, developed using MINOS linear programming solver. The new heuristic can generate optimal/near-optimal solutions in a fraction of the time needed to compute the optimal solution by Land and Powell code. The solution technique is based on restricted search using branch and bound technique. The efficiency of the heuristic approach is demonstrated by numerical results for a set of test problems.

  12. Radial engine

    SciTech Connect

    Kmicikiewicz, M.A.

    1988-03-01

    A radial engine is described comprising: a housing; equally spaced openings disposed in ring-like arrangement on the periphery of the housing; a piston and cylinder arrangement in each of the opening, a piston rod for each arrangement fixed to and extending radially inwardly from its respective piston and through its respective opening; shoe means pivotally attached at the other end of each of the piston rod; radial guide means extending in the housing in line with each of the piston rods, and the shoe means provided with guide means followers to ensure radial reciprocal movement of the piston rods and shoe means; and a connecting ring journaled on a crankshaft for circular translation motion in the housing, the ring including a circular rim. Each shoe means includes an arcuate follower member being slidably connected to the rim of the connecting ring.

  13. Obstructive membrane at the base of the left atrial appendage, a multi-imaging approach.

    PubMed

    Chejtman, Demián; Failo, Matías; Richarte Rueda, Valeria; Logarzo, Emilio; Barja, Luis; Benticuaga, Alejandro; Ayerdi, Maria Laura; Turri, Domingo; Baratta, Sergio; Aguirre, Pablo; Hita, Alejandro

    2015-05-01

    The left atrial appendage (LAA) is a small muscular extension that grows from the anterolateral wall of the left atrium, in the proximity of the left pulmonary veins. The presence of a membrane in the LAA is a rare clinical entity whose origin is not known. Its clinical implication in the genesis of atrial arrhythmias and thromboembolic risk remains unknown. We report a case of an obstructive membrane located at the base of the LAA, found incidentally in a young patient who was initially undergoing a transesophageal echocardiogram prior to an invasive treatment for atrial fibrillation.

  14. Comparison of the morphometric features of the left and right horse kidneys: a stereological approach.

    PubMed

    Bolat, D; Bahar, S; Tipirdamaz, S; Selcuk, M L

    2013-12-01

    The aims of this study were to determine the total volume of the horse kidney and volume fractions of its functional subcomponents (cortex, medulla, renal pelvis) using stereological methods and investigate any possible difference in the functional subcomponents of the right and left kidneys that may arise from differences in shape. The study was carried out on the kidneys of 5 horses of different breed and sex. The weight of the kidneys was measured by a digital scale, and kidney volume was calculated by Archimedes' principle. Total kidney volume and volume fractions of subcomponents of the right and left kidneys were estimated by the Cavalieri's principle. The weights of the right and left kidneys were 550 ± 25 g and 585 ± 23 g, respectively. The volumes of the right and left kidneys estimated using the Cavalieri method were 542 ± 46 ml and 581 ± 29 ml. The relative organ weight of the kidneys was calculated as 1:330. The densities of the right and left kidneys were determined to be 1.01 and 1.00, respectively. The mean volume fractions of the cortex, medulla and renal pelvis were determined as 55.6, 42.7 and 1.7 in both kidneys. No statistically significant difference existed between morphometric data pertaining to the right and left kidneys (P > 0.05). To determine precisely whether differences in shape cause any difference in the functional subcomponents of the right and left kidneys requires further investigation of differences in the number of microscopically functional unit of the kidney such as renal glomeruli and nephrons.

  15. Physiopathological approach to infective endocarditis in chronic hemodialysis patients: left heart versus right heart involvement.

    PubMed

    Bentata, Yassamine

    2017-11-01

    Infectious endocarditis (IE), a complication that is both cardiac and infectious, occurs frequently and is associated with a heavy burden of morbidity and mortality in chronic hemodialysis patients (CHD). About 2-6% of chronic hemodialysis patients develop IE and the incidence is 50-60 times higher among CHD patients than in the general population. The left heart is the most frequent location of IE in CHD and the different published series report a prevalence of left valve involvement varying from 80% to 100%. Valvular and perivalvular abnormalities, alteration of the immune system, and bacteremia associated with repeated manipulation of the vascular access, particularly central venous catheters, comprise the main factors explaining the left heart IE in CHD patients. While left-sided IE develops in altered valves in a high-pressure system, right-sided IE on the contrary, generally develops in healthy valves in a low-pressure system. Right-sided IE is rare, with its incidence varying from 0% to 26% depending on the study, and the tricuspid valve is the main location. Might the massive influx of pathogenic and virulent germs via the central venous catheter to the right heart, with the tricuspid being the first contact valve, have a role in the physiopathology of IE in CHD, thus facilitating bacterial adhesion? While the physiopathology of left-sided IE entails multiple and convincing mechanisms, it is not the case for right-sided IE, for which the physiopathological mechanism is only partially understood and remains shrouded in mystery.

  16. Lateral left ventricular wall rupture following acute myocardial infarction: pathophysiological interpretation by multimodality imaging approach.

    PubMed

    Avegliano, Gustavo; Conde, Diego; González Ruiz, María Isabel; Kuschnir, Paola; Sciancalepore, Agustina; Castro, Florencia; Ronderos, Ricardo

    2014-11-01

    Lateral left ventricular wall rupture (LVWR) is a rare complication following acute myocardial infarction (AMI) less than 1%. After cardiogenic shock, LVWR constitutes the most common cause of in-hospital death in AMI patients. Around 40% of all LVWR occurred during the first 24 hours and 85% within the first week. In the present case, 76 hours following the intervention, LVWR was observed likely due to a small infarction at the lateral left ventricular wall possibly due to the marginal lesion. Our patient refused surgery and was followed clinically. Eighteen months later, real time three-dimensional echocardiography showed a pseudoaneurysm.

  17. A Change Management, Systems Thinking, or Organizational Development Approach to the No Child Left Behind Act

    ERIC Educational Resources Information Center

    Galloway, Dominique L.

    2007-01-01

    Problems with implementation of the No Child Left Behind Act (NCLB) can be assessed in light of change management theory. Viewing stakeholders collectively as a corporate entity supports employing change management strategies to make the NCLB work. Examining ways that organizational controls and change management can work together points to…

  18. An Intelligent Approach to Educational Data: Performance Comparison of the Multilayer Perceptron and the Radial Basis Function Artificial Neural Networks

    ERIC Educational Resources Information Center

    Kayri, Murat

    2015-01-01

    The objective of this study is twofold: (1) to investigate the factors that affect the success of university students by employing two artificial neural network methods (i.e., multilayer perceptron [MLP] and radial basis function [RBF]); and (2) to compare the effects of these methods on educational data in terms of predictive ability. The…

  19. Comparison of interatomic potentials of water via structure factors reconstructed from simulated partial radial distribution functions: a reverse Monte Carlo based approach

    NASA Astrophysics Data System (ADS)

    Steinczinger, Zsuzsanna; Jóvári, Pál; Pusztai, László

    2017-01-01

    Neutron- and x-ray weighted total structure factors of liquid water have been calculated on the basis of the intermolecular parts of partial radial distribution functions resulting from various computer simulations. The approach includes reverse Monte Carlo (RMC) modelling of these partials, using realistic flexible molecules, and the calculation of experimental diffraction data, including the intramolecular contributions, from the RMC particle configurations. The procedure has been applied to ten sets of intermolecular partial radial distribution functions obtained from various computer simulations, including one set from an ab initio molecular dynamics, of water. It is found that modern polarizable water potentials, such as SWM4-DP and BK3 are the most successful in reproducing measured diffraction data.

  20. Feasibility and Safety of Transradial Arterial Approach for Simultaneous Right and Left Vertebral Artery Angiographic Studies and Stenting

    SciTech Connect

    Yip, H.-K.; Youssef, Ali A.; Chang, W.-N.; Lu, C.-H.; Yang, C.-H.; Chen, S.-M.; Wu, C.-J.

    2007-09-15

    Objectives. This study investigated whether the transradial artery (TRA) approach using a 6-French (F) Kimny guiding catheter for right vertebral artery (VA) angiographic study and stenting is safe and effective for patients with significant VA stenosis. Background. The TRA approach is commonly performed worldwide for both diagnostic cardiac catheterization and catheter-based coronary intervention. However, to our knowledge, the safety and feasibility of left and right VA angiographic study and stenting, in the same procedure, using the TRA approach for patients with brain ischemia have not been reported. Methods. The study included 24 consecutive patients (22 male, 2 female; age, 63-78 years). Indications for VA angiographic study and stenting were (1) prior stroke or symptoms related to vertebrobasilar ischemia and (2) an asymptomatic but vertebral angiographic finding of severe stenosis (>70%). A combination of the ipsilateral and retrograde-engagement technique, which involved a looping 6-F Kimny guiding catheter, was utilized for VA angiographic study. For VA stenting, an ipsilateral TRA approach with either a Kimny guiding catheter or a left internal mammary artery guiding catheter was utilized in 22 patients and retrograde-engagement technique in 2 patients. Results. A technically successful procedure was achieved in all patients, including left VA stenting in 15 patients and right VA stenting in 9 patients. The mean time for stenting (from engagement to stent deployment) was 12.7 min. There were no vascular complications or mortality. However, one patient suffered from a transient ischemic attack that resolved within 3 h. Conclusion. We conclude that TRA access for both VA angiographic study and VA stenting is safe and effective, and provides a simple and useful clinical tool for patients unsuited for femoral arterial access.

  1. Pelvic congestion syndrome and left renal compression syndrome - clinical features and therapeutic approaches.

    PubMed

    Jeanneret, Christina; Beier, Konstantin; von Weymarn, Alexander; Traber, Jürg

    2016-01-01

    Knowledge of the anatomy of the pelvic, gonadal and renal veins is important to understand pelvic congestion syndrome (PCS) and left renal vein compression syndrome (LRCS), which is also known as the nutcracker syndrome. LRCS is related to PCS and to the presence of vulvar, vaginal and pudendal varicose veins. The diagnosis of the two syndromes is difficult, and usually achieved with CT- or phlebography. The gold standard is the intravenous pressure measurement using conventional phlebography. The definition of PCS is described as pelvic pain, aggravated in the standing position and lasting for more than 6 months. Pain in the left flank and microhaematuria is seen in patients with LRCS. Women with multiple pregnancies are at increased risk of developing varicose vein recurrences with pelvic drainage and ovarian vein reflux after crossectomy and stripping of the great saphenous vein. The therapeutic options are: conservative treatment (medroxyprogesteron) or interventional (coiling of the ovarian vein) or operative treatment (clipping of the ovarian vein). Controlled prospective trials are needed to find the best treatment.

  2. Laparoscopic left and right adrenalectomy from an anterior approach – is there any difference? Outcomes in 176 consecutive patients

    PubMed Central

    Kokorak, Lukas; Vladovic, Peter; Marko, Lubomir

    2016-01-01

    Introduction Traditionally, in open surgery, right adrenalectomy is considered technically more demanding than its left-sided counterpart. This belief is supposed to be attributable mainly to different anatomic characteristics of the adrenal veins. Whether this opinion is also correct for laparoscopic adrenalectomy remains elusive. Aim To compare the outcomes of left versus right laparoscopic adrenalectomy from an anterior approach. Material and methods Retrospective statistical analysis of a prospectively compiled database of consecutive patients undergoing laparoscopic adrenalectomy in a single center with focus on potential differences in the left- versus right-sided procedure in terms of demographic parameters, tumor size, operating time, occurrence of serious intraoperative complications, conversion, length of hospital stay and re-operation rate. Results One hundred seventy-six patients underwent elective laparoscopic adrenalectomy – 80 left-sided (45.45%) and 96 right-sided (54.55%). No significant difference was found between the groups in terms of age (54.09 ±11.2 vs. 56.27 ±11.6; p = 0.2), tumor size (3.39 ±1.86 vs. 3.26 ±1.66; p = 0.64), operating time (71.84 ±22.33 vs. 72.06 ±30.99; p = 0.95), occurrence of serious intraoperative complications (7.5% vs. 10.4%; p = 0.5), conversion (1.25% vs. 1.04%; p = 0.9), length of hospital stay (4.52 ±1.30 vs. 4.37 ±1.91; p = 0.55) or reoperation rate (5% vs. 1%; p = 0.11). There was no mortality. Conclusions No significant difference was found between the left and right laparoscopic adrenalectomy in terms of operating time, occurrence of serious intraoperative complications, conversion rate or postoperative outcome. Therefore, the opinion that the right-sided procedure is more difficult does not seem to be justified for laparoscopic adrenalectomy from the anterior approach. PMID:28194247

  3. Radial-radial single rotor turbine

    SciTech Connect

    Platts, David A.

    2006-05-16

    A rotor for use in turbine applications has a radial compressor/pump having radially disposed spaced apart fins forming passages and a radial turbine having hollow turbine blades interleaved with the fins and through which fluid from the radial compressor/pump flows. The rotor can, in some applications, be used to produce electrical power.

  4. Radial expansion of the tail current disruption during substorms - A new approach to the substorm onset region

    NASA Technical Reports Server (NTRS)

    Ohtani, S.; Kokubun, S.; Russell, C. T.

    1992-01-01

    A new method is used to examine the radial expansion of the tail current disruption and the substorm onset region. The expansion of the disruption region is specified by examining the time sequence (phase relationship) between the north-south component and the sun-earth component. This method is tested by applying it to the March 6, 1979, event. The phase relationship indicates that the current disruption started on the earthward side of the spacecraft, and expanded tailward past the spacecraft. The method was used for 13 events selected from the ISEE magnetometer data. The results indicate that the current disruption usually starts in the near-earth magnetotail and often within 15 RE from the earth.

  5. Common ground: exploring policy approaches to addressing racial disparities from the left and the right.

    PubMed

    Gibbons, M C

    2006-01-01

    Although the existence of racial and ethnic disparities is increasingly recognized, a complete understanding of the causes and solutions to these problems remains elusive. Part One of this paper provides a historical overview of the origins of these disparities. Part Two outlines fundamental challenges to achieving a clear understanding of the problem and briefly discusses current policy strategies espoused by conservative and liberal proponents. Finally, Part Three provides an in-depth discussion of one promising approach with significant bipartisan support.

  6. A Bayesian approach to infer the radial distribution of temperature and anisotropy in the transition zone from seismic data

    NASA Astrophysics Data System (ADS)

    Drilleau, M.; Beucler, E.; Mocquet, A.; Verhoeven, O.; Moebs, G.; Burgos, G.; Montagner, J.

    2013-12-01

    Mineralogical transformations and matter transfers within the Earth's mantle make the 350-1000 km depth range (considered here as the mantle transition zone) highly heterogeneous and anisotropic. Most of the 3-D global tomographic models are anchored on small perturbations from 1-D models such as PREM, and are secondly interpreted in terms of temperature and composition distributions. However, the degree of heterogeneity in the transition zone can be strong enough so that the concept of a 1-D reference seismic model may be addressed. To avoid the use of any seismic reference model, we developed a Markov chain Monte Carlo algorithm to directly interpret surface wave dispersion curves in terms of temperature and radial anisotropy distributions, considering a given composition of the mantle. These interpretations are based on laboratory measurements of elastic moduli and Birch-Murnaghan equation of state. An originality of the algorithm is its ability to explore both smoothly varying models and first-order discontinuities, using C1-Bézier curves, which interpolate the randomly chosen values for depth, temperature and radial anisotropy. This parameterization is able to generate a self-adapting parameter space exploration while reducing the computing time. Using a Bayesian exploration, the probability distributions on temperature and anisotropy are governed by uncertainties on the data set. The method was successfully applied to both synthetic data and real dispersion curves. Surface wave measurements along the Vanuatu- California path suggest a strong anisotropy above 400 km depth which decreases below, and a monotonous temperature distribution between 350 and 1000 km depth. On the contrary, a negative shear wave anisotropy of about 2 % is found at the top of the transition zone below Eurasia. Considering compositions ranging from piclogite to pyrolite, the overall temperature profile and temperature gradient are higher for the continental path than for the oceanic

  7. Consensus document on the radial approach in percutaneous cardiovascular interventions: position paper by the European Association of Percutaneous Cardiovascular Interventions and Working Groups on Acute Cardiac Care** and Thrombosis of the European Society of Cardiology.

    PubMed

    Hamon, Martial; Pristipino, Christian; Di Mario, Carlo; Nolan, James; Ludwig, Josef; Tubaro, Marco; Sabate, Manel; Mauri-Ferré, Josepa; Huber, Kurt; Niemelä, Kari; Haude, Michael; Wijns, William; Dudek, Dariusz; Fajadet, Jean; Kiemeneij, Ferdinand

    2013-03-01

    Radial access use has been growing steadily but, despite encouraging results, still varies greatly among operators, hospitals, countries and continents. Twenty years from its introduction, it was felt that the time had come to develop a common evidence-based view on the technical, clinical and organisational implications of using the radial approach for coronary angiography and interventions. The European Association of Percutaneous Cardiovascular Interventions (EAPCI) has, therefore, appointed a core group of European and non-European experts, including pioneers of radial angioplasty and operators with different practices in vascular access supported by experts nominated by the Working Groups on Acute Cardiac Care and Thrombosis of the European Society of Cardiology (ESC). Their goal was to define the role of the radial approach in modern interventional practice and give advice on technique, training needs, and optimal clinical indications.

  8. Radial Halbach Magnetic Bearings

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.; Gallo, Christopher A.; Thompson, William K.

    2009-01-01

    minimizing it on the opposite side. The advantage of this configuration is that it makes it possible to approach the theoretical maximum force per unit area that could be exerted by a given amount of permanent-magnet material. The configuration is named after physicist Klaus Halbach, who conceived it for use in particle accelerators. Halbach arrays have also been studied for use in magnetic-levitation ("maglev") railroad trains. In a radial Halbach magnetic bearing, the basic Halbach arrangement is modified into a symmetrical arrangement of sector-shaped permanent magnets mounted on the outer cylindrical surface of a drum rotor (see Figure 2). The magnets are oriented to concentrate the magnetic field on their radially outermost surface. The stator coils are mounted in a stator shell surrounding the rotor.

  9. A Combined Random Forests and Active Contour Model Approach for Fully Automatic Segmentation of the Left Atrium in Volumetric MRI

    PubMed Central

    Luo, Gongning

    2017-01-01

    Segmentation of the left atrium (LA) from cardiac magnetic resonance imaging (MRI) datasets is of great importance for image guided atrial fibrillation ablation, LA fibrosis quantification, and cardiac biophysical modelling. However, automated LA segmentation from cardiac MRI is challenging due to limited image resolution, considerable variability in anatomical structures across subjects, and dynamic motion of the heart. In this work, we propose a combined random forests (RFs) and active contour model (ACM) approach for fully automatic segmentation of the LA from cardiac volumetric MRI. Specifically, we employ the RFs within an autocontext scheme to effectively integrate contextual and appearance information from multisource images together for LA shape inferring. The inferred shape is then incorporated into a volume-scalable ACM for further improving the segmentation accuracy. We validated the proposed method on the cardiac volumetric MRI datasets from the STACOM 2013 and HVSMR 2016 databases and showed that it outperforms other latest automated LA segmentation methods. Validation metrics, average Dice coefficient (DC) and average surface-to-surface distance (S2S), were computed as 0.9227 ± 0.0598 and 1.14 ± 1.205 mm, versus those of 0.6222–0.878 and 1.34–8.72 mm, obtained by other methods, respectively. PMID:28316992

  10. "Happy Days Are Here Again": A Left and Right Brain 4MAT Approach to Teaching Depression-Era Presidential Elections.

    ERIC Educational Resources Information Center

    Cantu, D. Antonio

    2001-01-01

    Provides a lesson plan that focuses on the 1932, 1936, and 1940 presidential election campaigns. Illustrates the use of the left and right brain 4MAT teaching model that considers individual learning styles associated with right and left hemisphere dominance. Includes a bibliography and eight handouts. (CMK)

  11. Flow-volume loops derived from three-dimensional echocardiography: a novel approach to the assessment of left ventricular hemodynamics

    PubMed Central

    Shahgaldi, Kambiz; Söderqvist, Emil; Gudmundsson, Petri; Winter, Reidar; Nowak, Jacek; Brodin, Lars-Åke

    2008-01-01

    Background This study explores the feasibility of non-invasive evaluation of left ventricular (LV) flow-volume dynamics using 3-dimensional (3D) echocardiography, and the capacity of such an approach to identify altered LV hemodynamic states caused by valvular abnormalities. Methods Thirty-one patients with moderate-severe aortic (AS) and mitral (MS) stenoses (21 and 10 patients, respectively) and 10 healthy volunteers underwent 3D echocardiography with full volume acquisition using Philips Sonos 7500 equipment. The digital 3D data were post- processed using TomTec software. LV flow-volume loops were subsequently constructed for each subject by plotting instantaneous LV volume data sampled throughout the cardiac cycle vs. their first derivative representing LV flow. After correction for body surface area, an average flow-volume loop was calculated for each subject group. Results Flow-volume loops were obtainable in all subjects, except 3 patients with AS. The flow-volume diagrams displayed clear differences in the form and position of the loops between normal individuals and the respective patient groups. In patients with AS, an "obstructive" pattern was observed, with lower flow values during early systole and larger end-systolic volume. On the other hand, patients with MS displayed a "restrictive" flow-volume pattern, with reduced diastolic filling and smaller end-diastolic volume. Conclusion Non-invasive evaluation of LV flow-volume dynamics using 3D-echocardiographic data is technically possible and the approach has a capacity to identify certain specific types of alteration of LV flow-volume pattern caused by valvular abnormalities, thus reflecting underlying hemodynamic states specific for these abnormalities. PMID:18394157

  12. Potential Molecular Mechanism of Retrograde Aortic Arch Stenosis in the Hybrid Approach to Hypoplastic Left Heart Syndrome

    PubMed Central

    Hibino, Narutoshi; Cismowski, Mary J.; Lilly, Brenda J.; McConnell, Patrick I.; Shinoka, Toshiharu; Cheatham, John P.; Lucchesi, Pamela A.; Galantowicz, Mark E.; Trask, Aaron J.

    2015-01-01

    Background The hybrid palliation for hypoplastic left heart syndrome (HLHS) has emerged as an alternative approach to the Norwood procedure. The development of patent ductus arteriosus (PDA) in-stent stenosis can cause retrograde aortic arch stenosis (RAAS), leading to significant morbidity. This study aimed to identify potential mechanisms of PDA in-stent stenosis contributing to RAAS. METHODS Tissues from stented PDA were collected from 17 patients undergoing comprehensive stage 2 repair between 2009 and 2014. Patients requiring RAAS intervention based on cardiology–surgery consensus were defined as RAAS (+) (n=10), whereas patients without any RAAS intervention were defined as RAAS (−) (n=7). Tissues were examined by qPCR analysis for vascular smooth muscle cell (VSMC) differentiation and proliferation markers. RESULTS Patient characteristics were: HLHS with aortic atresia: 6; HLHS with aortic stenosis: 3; unbalanced AVC: 3; DILV/TGA: 3; DORV: 2. VSMC differentiation markers (β–actin, SM22, and calponin) and signaling pathways for VSMC modulation (TGFβ1, Notch, and PDGF-BB) were significantly higher in the RAAS (+) than in RAAS (−). The proliferation marker Ki67 was increased in RAAS (+). Cell cycle markers were comparable in both groups. CONCLUSION Increased VSMC differentiation and proliferation markers suggest a mechanism for inward neointima formation of the PDA in RAAS. The apparent lack of change in cell cycle markers is contrary to coronary artery in-stent stenosis, suggesting further targets should be examined. Combined primary in vitro PDA cell culture and proteomics can be strong tools to elucidate targets to reduce PDA in-stent stenosis for RAAS in the future. PMID:26163359

  13. Radial Artery Catheterization

    MedlinePlus

    ... of the radial artery for cardiac catheterization procedures. Advantages of Radial Artery Catheterization Any catheter placement into ... walk, and eat immediately. This is a particular advantage for patients with back problems because there is ...

  14. Differences between left- and right-handers in approach/avoidance motivation: influence of consistency of handedness measures.

    PubMed

    Hardie, Scott M; Wright, Lynn

    2014-01-01

    Hand preference is often viewed as a troublesome variable in psychological research, with left-handers routinely excluded from studies. Contrary to this, a body of evidence has shown hand preference to be a useful variable when examining human behavior. A recent review argues that the most effective way of using handedness as a variable, is a comparison between individuals who use their dominant hand for virtually all manual activities (consistent handers) versus those who use their other hand for at least one activity (inconsistent handers). The authors contend that researchers should only focus on degree of handedness rather than direction of preference (left versus right). However, we argue that the field suffers from a number of methodological and empirical issues. These include a lack of consensus in choice of cut-off point to divide consistent and inconsistent categories and importantly a paucity of data from left-handers. Consequentially, researchers predominantly compare inconsistent versus consistent right-handers, largely linked to memory, cognition and language. Other research on response style and personality measures shows robust direction of handedness effects. The present study examines both strength and direction of handedness on self-reported behavioral inhibition system (BIS) and behavioral activation system (BAS) scores, using evidence from a large (N = 689) dataset including more than 200 left-handers. There were degree of handedness effects on BIS and BAS-Fun Seeking, but effects are largely driven by differences between consistent left-handers and other groups. Choice of cut-off point substantively influenced results, and suggests that unless a suitable sample of left-handers is included, researchers clarify that their degree of handedness effects are applicable only to right-handers. We concur that strength of hand preference is an important variable but caution that differences related to consistency may not be identical in right and left-handers.

  15. Differences between left- and right-handers in approach/avoidance motivation: influence of consistency of handedness measures

    PubMed Central

    Hardie, Scott M.; Wright, Lynn

    2014-01-01

    Hand preference is often viewed as a troublesome variable in psychological research, with left-handers routinely excluded from studies. Contrary to this, a body of evidence has shown hand preference to be a useful variable when examining human behavior. A recent review argues that the most effective way of using handedness as a variable, is a comparison between individuals who use their dominant hand for virtually all manual activities (consistent handers) versus those who use their other hand for at least one activity (inconsistent handers). The authors contend that researchers should only focus on degree of handedness rather than direction of preference (left versus right). However, we argue that the field suffers from a number of methodological and empirical issues. These include a lack of consensus in choice of cut-off point to divide consistent and inconsistent categories and importantly a paucity of data from left-handers. Consequentially, researchers predominantly compare inconsistent versus consistent right-handers, largely linked to memory, cognition and language. Other research on response style and personality measures shows robust direction of handedness effects. The present study examines both strength and direction of handedness on self-reported behavioral inhibition system (BIS) and behavioral activation system (BAS) scores, using evidence from a large (N = 689) dataset including more than 200 left-handers. There were degree of handedness effects on BIS and BAS-Fun Seeking, but effects are largely driven by differences between consistent left-handers and other groups. Choice of cut-off point substantively influenced results, and suggests that unless a suitable sample of left-handers is included, researchers clarify that their degree of handedness effects are applicable only to right-handers. We concur that strength of hand preference is an important variable but caution that differences related to consistency may not be identical in right and left

  16. Asymptotic screened hydrogenic radial integrals

    NASA Technical Reports Server (NTRS)

    Olsgaard, D. A.; Khan, F.; Khandelwal, G. S.

    1988-01-01

    The usefulness of the screened hydrogenic model for the transitions of the helium sequence is studied. The screened hydrogenic radial dipole integral for discrete-discrete transitions from the initial state to the final state is asymptotically expanded to the lowest order such that the final quantum number n approaches infinity. The analytical expression obtained is in terms of confluent hypergeometric functions.

  17. KANTBP: A program for computing energy levels, reaction matrix and radial wave functions in the coupled-channel hyperspherical adiabatic approach

    NASA Astrophysics Data System (ADS)

    Chuluunbaatar, O.; Gusev, A. A.; Abrashkevich, A. G.; Amaya-Tapia, A.; Kaschiev, M. S.; Larsen, S. Y.; Vinitsky, S. I.

    2007-10-01

    A FORTRAN 77 program is presented which calculates energy values, reaction matrix and corresponding radial wave functions in a coupled-channel approximation of the hyperspherical adiabatic approach. In this approach, a multi-dimensional Schrödinger equation is reduced to a system of the coupled second-order ordinary differential equations on the finite interval with homogeneous boundary conditions of the third type. The resulting system of radial equations which contains the potential matrix elements and first-derivative coupling terms is solved using high-order accuracy approximations of the finite-element method. As a test desk, the program is applied to the calculation of the energy values and reaction matrix for an exactly solvable 2D-model of three identical particles on a line with pair zero-range potentials. Program summaryProgram title: KANTBP Catalogue identifier: ADZH_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADZH_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 4224 No. of bytes in distributed program, including test data, etc.: 31 232 Distribution format: tar.gz Programming language: FORTRAN 77 Computer: Intel Xeon EM64T, Alpha 21264A, AMD Athlon MP, Pentium IV Xeon, Opteron 248, Intel Pentium IV Operating system: OC Linux, Unix AIX 5.3, SunOS 5.8, Solaris, Windows XP RAM: depends on (a) the number of differential equations; (b) the number and order of finite-elements; (c) the number of hyperradial points; and (d) the number of eigensolutions required. Test run requires 30 MB Classification: 2.1, 2.4 External routines: GAULEG and GAUSSJ [W.H. Press, B.F. Flanery, S.A. Teukolsky, W.T. Vetterley, Numerical Recipes: The Art of Scientific Computing, Cambridge University Press, Cambridge, 1986] Nature of problem: In the hyperspherical adiabatic

  18. Many States Have Taken a "Backloaded" Approach to No Child Left Behind Goal of All Students Scoring "Proficient"

    ERIC Educational Resources Information Center

    Chudowsky, Naomi; Chudowsky, Vic

    2008-01-01

    This report examines the interim objectives for student achievement established by states in their accountability plans for the No Child Left Behind Act. These objectives lay out the percentages of students that must score at or above the proficient level on state tests each year, on the way toward meeting the law's ultimate goal of 100% of…

  19. Right-Left Approach and Reaching Arm Movements of 4-Month Infants in Free and Constrained Conditions

    ERIC Educational Resources Information Center

    Morange-Majoux, Francoise; Dellatolas, Georges

    2010-01-01

    Recent theories on the evolution of language (e.g. Corballis, 2009) emphazise the interest of early manifestations of manual laterality and manual specialization in human infants. In the present study, left- and right-hand movements towards a midline object were observed in 24 infants aged 4 months in a constrained condition, in which the hands…

  20. A novel hydrodynamic approach of drag-reducing polymers to improve left ventricular hypertrophy and aortic remodeling in spontaneously hypertensive rats

    PubMed Central

    Zhang, Xinlu; Wang, Xu; Hu, Feng; Zhou, Boda; Chen, Hai-Bin; Zha, Daogang; Liu, Yili; Guo, Yansong; Zheng, Lemin; Xiu, Jiancheng

    2016-01-01

    Drag-reducing polymers (DRPs), when added in minute concentrations, have been shown to decrease peripheral vascular resistance. In this study, the effect of DRPs on the hypertension-induced left ventricular hypertrophy and aortic remodeling was evaluated in spontaneously hypertensive rats (SHR). Male SHR and age-matched Wistar rats were divided into four groups and received intravenous injection of normal saline (NS) or DRPs. Body weight (BW), heart rate (HR) and systolic blood pressure (SBP) were measured. Echocardiography was used to evaluate the changes in left ventricle (LV) function and global wall motion. The LV and aorta were stained by hematoxylin and eosin. Cell size of cardiomyocytes and aortic medial thickness were evaluated for each section. The expression of endothelin-1 (ET-1) of LV and aorta was examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. There was no significant difference in the increase of SBP among SHR + NS, SHR + 10DRP and SHR + 20DRP groups. SHR + NS group had markedly smaller left ventricular end-systolic diameter and left ventricular end-diastolic diameter but bigger anterior and posterior systolic wall thicknesses, while there was no significant difference in fractional shortening and ejection fraction. The cross-sectional areas (CSAs) of cardiomyocytes and the medial thickness of the aorta in SHR + 10 (ppm) DRP and SHR + 20 (ppm) DRP groups were significantly reduced compared with SHR + NS group. The expression of ET-1 in SHR + 10DRP and SHR + 20DRP groups was significantly attenuated. These results suggest that chronic treatment with DRPs can protect against left ventricular hypertrophy and aortic remodeling. DRPs may offer a new approach to the treatment of left ventricular hypertrophy and aortic remodeling caused by hypertension. PMID:28008249

  1. A novel hydrodynamic approach of drag-reducing polymers to improve left ventricular hypertrophy and aortic remodeling in spontaneously hypertensive rats.

    PubMed

    Zhang, Xinlu; Wang, Xu; Hu, Feng; Zhou, Boda; Chen, Hai-Bin; Zha, Daogang; Liu, Yili; Guo, Yansong; Zheng, Lemin; Xiu, Jiancheng

    Drag-reducing polymers (DRPs), when added in minute concentrations, have been shown to decrease peripheral vascular resistance. In this study, the effect of DRPs on the hypertension-induced left ventricular hypertrophy and aortic remodeling was evaluated in spontaneously hypertensive rats (SHR). Male SHR and age-matched Wistar rats were divided into four groups and received intravenous injection of normal saline (NS) or DRPs. Body weight (BW), heart rate (HR) and systolic blood pressure (SBP) were measured. Echocardiography was used to evaluate the changes in left ventricle (LV) function and global wall motion. The LV and aorta were stained by hematoxylin and eosin. Cell size of cardiomyocytes and aortic medial thickness were evaluated for each section. The expression of endothelin-1 (ET-1) of LV and aorta was examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. There was no significant difference in the increase of SBP among SHR + NS, SHR + 10DRP and SHR + 20DRP groups. SHR + NS group had markedly smaller left ventricular end-systolic diameter and left ventricular end-diastolic diameter but bigger anterior and posterior systolic wall thicknesses, while there was no significant difference in fractional shortening and ejection fraction. The cross-sectional areas (CSAs) of cardiomyocytes and the medial thickness of the aorta in SHR + 10 (ppm) DRP and SHR + 20 (ppm) DRP groups were significantly reduced compared with SHR + NS group. The expression of ET-1 in SHR + 10DRP and SHR + 20DRP groups was significantly attenuated. These results suggest that chronic treatment with DRPs can protect against left ventricular hypertrophy and aortic remodeling. DRPs may offer a new approach to the treatment of left ventricular hypertrophy and aortic remodeling caused by hypertension.

  2. Internal low energy cardioversion of atrial fibrillation using a single lead system: comparison of a left and right pulmonary artery catheter approach.

    PubMed

    Schmieder, S; Schneider, M A; Karch, M R; Schmitt, C

    2001-07-01

    Internal cardioversion (ICV) has been demonstrated as an effective and safe method for restoring sinus rhythm in patients with AF. Recently, a new single lead system with a balloon-guided cardioversion catheter was introduced. ICV was performed after advancing a 7.5 Fr catheter flow-directed into the left or right pulmonary artery (PA, distal array, cathode). The proximal array (anode) was placed at the lateral RA wall. Synchronized shocks (3/3 ms biphasic impulse) were applied using a stepwise protocol (0.5, 3, 6, 9, 12, 15 J) until sinus rhythm was restored or maximum energy (15 J) was reached. Sixty-five patients (mean age 58 +/- 13 years) with acute and chronic AF were included. Sinus rhythm could be restored in 59 (91%) patients. Cardioversion success was 93% in the left PA compared to 86% in right PA. DFTs for the left and right PA approaches were 7.1 +/- 4.0 J and 10.2 +/- 4.0 J, respectively (P < 0.0001). It was significantly higher in patients with an AF history > 7 days (7.2 +/- 4.1 J) than for those with a recent onset of AF (5.6 +/- 4.1 J), P = 0.0012. Shock impedance differed for the left and right PA lead configuration (53 +/- 11 vs 49 +/- 13 omega, P < 0.05). A right PA lead configuration is as effective compared to a left PA catheter approach when performing ICV for AF. ICV with a single lead system is safe and cardioversion success is comparable to other internal and external cardioversion techniques. In combination with hemodynamic monitoring, flow-directed nonfluoroscopic catheter positioning is feasible and may serve as a valuable therapeutic and diagnostic tool in intensive care units.

  3. Bilateral high radial nerve compressions: a case report.

    PubMed

    Chuangsuwanich, A; Muangsombut, S; Sangruchi, T

    2000-06-01

    A 40-year-old woman with bilateral high radial nerve compressions by non-traumatic cause was reported. It occurred first at the right radial nerve which was explored after a period of investigation and conservative treatment. Two constricted sites 2.0 cm apart of the right radial nerve crossed by branches of the radial collateral artery beneath the lateral head of the triceps were found. The constricted sites including tissue in between was resected and replaced with a sural nerve graft. One year later the patient had the same episode on the left side. The operative finding was the same as the previous one. Sural nerve graft was performed after neurolysis had failed. The patient's normal radial nerve function returned in one year. This is the first reported case in the literature of bilateral high radial nerve compressions by branches of the radial collateral artery.

  4. Radial arm strike rail

    DOEpatents

    McKeown, Mark H.; Beason, Steven C.

    1991-01-01

    The radial arm strike rail assembly is a system for measurement of bearings, directions, and stereophotography for geologic mapping, particularly where magnetic compasses are not appropriate. The radial arm, pivoting around a shaft axis, provides a reference direction determination for geologic mapping and bearing or direction determination. The centerable and levelable pedestal provide a base for the radial arm strike rail and the telescoping camera pedestal. The telescoping feature of the radial arm strike rail allows positioning the end of the rail for strike direction or bearing measurement with a goniometer.

  5. Novel anaesthetic approach for surgical access and haemodynamic management during off-pump coronary artery bypass through a left thoracotomy.

    PubMed

    Maddali, Madan Mohan; Al-Jadidi, Abdullah M; Zacharias, Sunny

    2012-01-01

    For myocardial revascularization on a beating heart through a thoracotomy, a properly deployed endobronchial blocker (EBB) provides ideal conditions for surgical access. In addition, adequate volume replacement to achieve optimal cardiac performance is a primary goal of haemodynamic management in patients undergoing off-pump coronary artery bypass grafting. To achieve both these ends, this case report describes the combined use of a left-sided EBB along with a volumetric pulmonary artery catheter in a patient who underwent a successful off-pump coronary artery bypass surgery through an anterolateral thoracotomy.

  6. Triple acting radial seal

    SciTech Connect

    Ebert, Todd A; Carella, John A

    2012-03-13

    A triple acting radial seal used as an interstage seal assembly in a gas turbine engine, where the seal assembly includes an interstage seal support extending from a stationary inner shroud of a vane ring, the interstage seal support includes a larger annular radial inward facing groove in which an outer annular floating seal assembly is secured for radial displacement, and the outer annular floating seal assembly includes a smaller annular radial inward facing groove in which an inner annular floating seal assembly is secured also for radial displacement. A compliant seal is secured to the inner annular floating seal assembly. The outer annular floating seal assembly encapsulates the inner annular floating seal assembly which is made from a very low alpha material in order to reduce thermal stress.

  7. Left-ventricle segmentation in real-time 3D echocardiography using a hybrid active shape model and optimal graph search approach

    NASA Astrophysics Data System (ADS)

    Zhang, Honghai; Abiose, Ademola K.; Campbell, Dwayne N.; Sonka, Milan; Martins, James B.; Wahle, Andreas

    2010-03-01

    Quantitative analysis of the left ventricular shape and motion patterns associated with left ventricular mechanical dyssynchrony (LVMD) is essential for diagnosis and treatment planning in congestive heart failure. Real-time 3D echocardiography (RT3DE) used for LVMD analysis is frequently limited by heavy speckle noise or partially incomplete data, thus a segmentation method utilizing learned global shape knowledge is beneficial. In this study, the endocardial surface of the left ventricle (LV) is segmented using a hybrid approach combining active shape model (ASM) with optimal graph search. The latter is used to achieve landmark refinement in the ASM framework. Optimal graph search translates the 3D segmentation into the detection of a minimum-cost closed set in a graph and can produce a globally optimal result. Various information-gradient, intensity distributions, and regional-property terms-are used to define the costs for the graph search. The developed method was tested on 44 RT3DE datasets acquired from 26 LVMD patients. The segmentation accuracy was assessed by surface positioning error and volume overlap measured for the whole LV as well as 16 standard LV regions. The segmentation produced very good results that were not achievable using ASM or graph search alone.

  8. Support vector analysis of color-Doppler images: a new approach for estimating indices of left ventricular function.

    PubMed

    Rojo-Alvarez, J L; Bermejo, J; Juárez-Caballero, V M; Yotti, R; Cortina, C; García-Fernández, M A; Antoranz, J C

    2006-08-01

    Reliable noninvasive estimators of global left ventricular (LV) chamber function remain unavailable. We have previously demonstrated a potential relationship between color-Doppler M-mode (CDMM) images and two basic indices of LV function: peak-systolic elastance (Emax) and the time-constant of LV relaxation (tau). Thus, we hypothesized that these two indices could be estimated noninvasively by adequate postprocessing of CDMM recordings. A semiparametric regression (SR) version of support vector machine (SVM) is here proposed for building a blind model, capable of analyzing CDMM images automatically, as well as complementary clinical information. Simultaneous invasive and Doppler tracings were obtained in nine mini-pigs in a high-fidelity experimental setup. The model was developed using a test and validation leave-one-out design. Reasonably acceptable prediction accuracy was obtained for both Emax (intraclass correlation coefficient Ric, = 0.81) and tau (Ric, = 0.61). For the first time, a quantitative, noninvasive estimation of cardiovascular indices is addressed by processing Doppler-echocardiography recordings using a learning-from-samples method.

  9. Radial heat flux transformer

    NASA Technical Reports Server (NTRS)

    Basiulis, A.; Buzzard, R. J.

    1971-01-01

    Unit moves heat radially from small diameter shell to larger diameter shell, or vice versa, with negligible temperature drop, making device useful wherever heating or cooling of concentrically arranged materials, substances, and structures is desired.

  10. Radial head fracture - aftercare

    MedlinePlus

    Elbow fracture - radial head - aftercare ... to 2 weeks. If you have a small fracture and your bones did not move around much, ... to see a bone doctor (orthopedic surgeon). Some fractures require surgery to: Insert pins and plates to ...

  11. Mathematical interpretation of radial shearing interferometers.

    PubMed

    Malacara, D

    1974-08-01

    The procedure for computing a radial shearing interferometric pattern is given. The interferometric pattern is analyzed to obtain the wavefront shape. Restricting the discussion to wavefronts having rotational symmetry, we give two different methods of finding the wavefront. One approach is to scan along a diameter of the interferometric pattern and the other is to examine the shape of the fringes. The relative sensitivity of a radial shearing interferometer with respect to that of a Twyman-Green interferometer is also analyzed.

  12. MAXBAND Version 3.1: Heuristic and optimal approach for setting the left turn phase sequences in signalized networks

    SciTech Connect

    Pillai, R.S.; Rathi, A.K.

    1995-02-01

    The main objective of synchronized signal timing is to keep traffic moving along arterials in platoons throughout the signal system by proper setting of left turn phase sequence at signals along the arterials/networks. The synchronization of traffic signals located along the urban/suburban arterials in metropolitan areas is perhaps one of the most cost-effective methods for improving traffic flow along these streets. MAXBAND Version 2.1 (formerly known as MAXBAND-86), a progression-based optimization model, is used for generating signal timing plan for urban networks. This model formulates the problem as a mixed integer linear program and uses Land and Powell branch and bound search to arrive at the optimal solution. The computation time of MAXBAND Version 2.1 tends to be excessive for realistic multiarterial network problems due to the exhaustive nature of the branch and bound search technique. Furthermore, the Land and Powell branch and bound code is known to be numerically unstable, which results in suboptimal solutions for network problems with a range on the cycle time variable. This report presents the development of a new version of MAXBAND called MAXBAND Version 3.1. This new version has a fast heuristic algorithm and a fast optimal algorithm for generating signal timing plan for arterials and networks. MAXBAND 3.1 can generate optimal/near-optimal solutions in fraction of the time needed to compute the optimal solution by Version 2.1. The heuristic algorithm in the new model is based on restricted search using branch and bound technique. The algorithm for generating the optimal solution is faster and more efficient than version 2.1 algorithm. Furthermore, the new version is numerically stable. The efficiency of the new model is demonstrated by numerical results for a set of test problems.

  13. Left atrial approach to close the atrial septal defect type II in case of right lung agenesis with extreme dextroversion.

    PubMed

    Pietrzykowski, Witold D; Moll, Maciej; Kobielski, Artur; Moll, Jacek J

    2007-02-01

    This paper presents a case of a rare combination of right lung agenesis and atrial septal defect type II (ASD II). Successful surgical repair of ASD II was performed at the age of six years with total circulatory arrest (TCA) and deep hypothermia, because of difficult approach. Computed tomography and intraoperative findings are described. From patho-embryological consideration, defects in the primitive respiratory apparatus in embryo stages were presumably responsible for agenesis of the lung. The patient was found to have a very short stump of the right pulmonary artery, but this malformation seems to be secondary.

  14. Radial turbine cooling

    NASA Technical Reports Server (NTRS)

    Roelke, Richard J.

    1992-01-01

    Radial turbines have been used extensively in many applications including small ground based electrical power generators, automotive engine turbochargers and aircraft auxiliary power units. In all of these applications the turbine inlet temperature is limited to a value commensurate with the material strength limitations and life requirements of uncooled metal rotors. To take advantage of all the benefits that higher temperatures offer, such as increased turbine specific power output or higher cycle thermal efficiency, requires improved high temperature materials and/or blade cooling. Extensive research is on-going to advance the material properties of high temperature superalloys as well as composite materials including ceramics. The use of ceramics with their high temperature potential and low cost is particularly appealing for radial turbines. However until these programs reach fruition the only way to make significant step increases beyond the present material temperature barriers is to cool the radial blading.

  15. The application of SHERPA (Systematic Human Error Reduction and Prediction Approach) in the development of compensatory cognitive rehabilitation strategies for stroke patients with left and right brain damage.

    PubMed

    Hughes, Charmayne M L; Baber, Chris; Bienkiewicz, Marta; Worthington, Andrew; Hazell, Alexa; Hermsdörfer, Joachim

    2015-01-01

    Approximately 33% of stroke patients have difficulty performing activities of daily living, often committing errors during the planning and execution of such activities. The objective of this study was to evaluate the ability of the human error identification (HEI) technique SHERPA (Systematic Human Error Reduction and Prediction Approach) to predict errors during the performance of daily activities in stroke patients with left and right hemisphere lesions. Using SHERPA we successfully predicted 36 of the 38 observed errors, with analysis indicating that the proportion of predicted and observed errors was similar for all sub-tasks and severity levels. HEI results were used to develop compensatory cognitive strategies that clinicians could employ to reduce or prevent errors from occurring. This study provides evidence for the reliability and validity of SHERPA in the design of cognitive rehabilitation strategies in stroke populations.

  16. Radial wedge flange clamp

    DOEpatents

    Smith, Karl H.

    2002-01-01

    A radial wedge flange clamp comprising a pair of flanges each comprising a plurality of peripheral flat wedge facets having flat wedge surfaces and opposed and mating flat surfaces attached to or otherwise engaged with two elements to be joined and including a series of generally U-shaped wedge clamps each having flat wedge interior surfaces and engaging one pair of said peripheral flat wedge facets. Each of said generally U-shaped wedge clamps has in its opposing extremities apertures for the tangential insertion of bolts to apply uniform radial force to said wedge clamps when assembled about said wedge segments.

  17. Radially uniform electron source

    NASA Technical Reports Server (NTRS)

    Mccomas, D.; Bame, S. J.

    1982-01-01

    A thermionic electron source capable of producing uniform count rates in a number of channel electron multipliers simultaneously was required for conditioning multipliers for an extended space mission. It was found that a straight tungsten filament in the center of a cylindrically symmetric geometry surrounded by an array of multipliers emits a radially asymmetric distribution of electrons that changes with time. A source was developed which successfully produces a time-independent radially uniform distribution of electrons by moving the filament out of the direct line of sight and replacing it with a centrally located electron 'cloud.'

  18. Elbow dislocation with irreparable fracture radial head

    PubMed Central

    Tanna, Dilip

    2013-01-01

    Background: Treatment of elbow dislocation with irreparable radial head fracture needs replacement of radial head to achieve stability of elbow. An alternate method in cases of elbow dislocation with radial head fracture can be resection of radial head with repair of medial collateral ligament. We report a retrospective analysis of cases of elbow dislocation with irreparable radial head treated by excision head of radius and repair of MCL. Materials and Methods: Nine patients of elbow dislocation with associated irreparable fractures of the head of the radius were included in this analysis (6 F:3 M, Age: 35-47 years). Radial head excision was done through the lateral approach and MCL was sutured using no 3 Ethibond using medial approach. Above elbow plaster was given for 6 weeks and gradual mobilization was done thereafter. All patients were assessed at final followup using Mayo elbow performance score (MEPS). Results: Mean followup was 19.55 ± 7.12 months (range 14-36 months). There was no extension deficit when compared to opposite side with mean range of flexion of 138.8° ± 6.97° (range 130 -145°). Mean pronation was 87.7° ± 4.4° (range 80-90°) and mean supination was 87.7 ± 4.62° (range 80-90°). The mean MEPS was 98.8 ± 3.33 (range 90-100). No patient had pain, sensory complaints, subluxation or redislocation. All were able to carry out their daily activities without disability. Conclusion: Radial head excision with MCL repair is an acceptable option for treatment of patients with elbow dislocation and irreparable radial head fracture. PMID:23798760

  19. Radial bisection of words and lines in right-brain-damaged patients with spatial neglect.

    PubMed

    Veronelli, Laura; Arduino, Lisa S; Girelli, Luisa; Vallar, Giuseppe

    2015-11-27

    The bisection of lines positioned radially (with the two ends of the line close and far, with respect to the participant's body) has been less investigated than that of lines placed horizontally (with their two ends left and right, with respect to the body's midsagittal plane). In horizontal bisection, patients with left neglect typically show a rightward bias for both lines and words, greater with longer stimuli. As for radial bisection, available data indicate that neurologically unimpaired participants make a distal error, while results from right-brain-damaged patients with left spatial neglect are contradictory. We investigated the bisection of radially oriented words, with the prediction that, during bisection, linguistic material would be recoded to its canonical left-to-right format in reading, with the performance of neglect patients being similar to that for horizontal words. Thirteen right-brain-damaged patients (seven with left spatial neglect) and fourteen healthy controls were asked to manually bisect 40 radial and 40 horizontal words (5-10 letters), and 80 lines, 40 radial and 40 horizontal, of comparable length. Right-brain-damaged patients with spatial neglect exhibited a proximal bias in the bisection of short radial words, with the proximal part corresponding to the final right part of horizontally oriented words. This proximal error was not found in patients without neglect and healthy controls. For bisection, short radial words may be recoded to the canonical orthographic horizontal format, unveiling the impact of left neglect on radially oriented stimuli.

  20. Temporary left ventricular assist device through an axillary access is a promising approach to improve outcomes in refractory cardiogenic shock patients.

    PubMed

    Doersch, Karen M; Tong, Carl W; Gongora, Enrique; Konda, Subbareddy; Sareyyupoglu, Basar

    2015-01-01

    Cardiogenic shock (CS) causes significant morbidity and mortality and such patients can deteriorate rapidly. Temporary left ventricular assist devices (LVADs) are a promising approach to manage these patients. The following is a case series in which patients stabilized with a temporary LVAD for CS improvement were analyzed retrospectively. Between June 2011 and January 2014, 15 patients received temporary devices through an axillary approach (mean age: 53 ± 15, 93% male). Mean survival time was 317.8 ± 359.5 days (range: 6-936 days). During support there were no major bleeding events, infectious complications at the axillary access site, upper extremity edema, or emboli. The most of the patients recovered from CS (93%) were mobilized (67%) and were extubated (73%) while on temporary device support. Median times to extubation, intensive care unit discharge, and discontinuation of inotropic medications were: 1.63, 18, and 15 days, respectively. Four patients recovered to no device support and five received a long-term LVAD, all of whom remain alive. Therefore, implantation of a temporary LVAD through an axillary approach is a promising therapy for improving outcomes in patients needing mechanical circulatory support as a bridge to recovery or a definitive LVAD.

  1. A case of secondary somatosensory epilepsy with a left deep parietal opercular lesion: successful tumor resection using a transsubcentral gyral approach during awake surgery.

    PubMed

    Maesawa, Satoshi; Fujii, Masazumi; Futamura, Miyako; Hayashi, Yuichiro; Iijima, Kentaro; Wakabayashi, Toshihiko

    2016-03-01

    Few studies have examined the clinical characteristics of patients with lesions in the deep parietal operculum facing the sylvian fissure, the region recognized as the secondary somatosensory area (SII). Moreover, surgical approaches in this region are challenging. In this paper the authors report on a patient presenting with SII epilepsy with a tumor in the left deep parietal operculum. The patient was a 24-year-old man who suffered daily partial seizures with extremely uncomfortable dysesthesia and/or occasional pain on his right side. MRI revealed a tumor in the medial aspect of the anterior transverse parietal gyrus, surrounding the posterior insular point. Long-term video electroencephalography monitoring with scalp electrodes failed to show relevant changes to seizures. Resection with cortical and subcortical mapping under awake conditions was performed. A negative response to stimulation was observed at the subcentral gyrus during language and somatosensory tasks; thus, the transcortical approach (specifically, a transsubcentral gyral approach) was used through this region. Subcortical stimulation at the medial aspect of the anterior parietal gyrus and the posterior insula around the posterior insular point elicited strong dysesthesia and pain in his right side, similar to manifestation of his seizure. The tumor was completely removed and pathologically diagnosed as pleomorphic xanthoastrocytoma. His epilepsy disappeared without neurological deterioration postoperatively. In this case study, 3 points are clinically significant. First, the clinical manifestation of this case was quite rare, although still representative of SII epilepsy. Second, the location of the lesion made surgical removal challenging, and the transsubcentral gyral approach was useful when intraoperative mapping was performed during awake surgery. Third, intraoperative mapping demonstrated that the patient experienced pain with electrical stimulation around the posterior insular point

  2. Extruder scale-up assessment in the process of extrusion-spheronization: comparison of radial and axial systems by a design of experiments approach.

    PubMed

    Désiré, Amélie; Paillard, Bruno; Bougaret, Joël; Baron, Michel; Couarraze, Guy

    2013-02-01

    Scaling-up the extrusion-spheronization process involves the separate scale-up of each of the five process steps: dry mixing, granulation, extrusion, spheronization, and drying. The aim of the study was to compare two screw extrusion systems regarding their suitability for scaling-up. Two drug substances of high- and low-solubility in water were retained at different concentrations as formulation variables. Different spheronization times were tested. The productivity of the process was followed up using the extrusion rate and yield. Pellets were characterized by their size and shape, and by their structural and mechanical properties. A response surface design of experiments was built to evaluate the influence of the different variables and their interactions on each response, and to select the type of extrusion which provides the best results in terms of product quality, the one which shows less influence on the product after scale-up ("scalability") and when the formula used changes ("robustness"), and the one which allows the possibility to adjust pellet properties with spheronization variables ("flexibility"). Axial system showed the best characteristics in terms of product quality at lab and industrial scales, the best robustness at industrial scale, and the best scalability, by comparison with radial system. Axial system thus appeared as the easiest scaled-up system. Compared to lab scale, the conclusions observed at industrial scale were the same in terms of product quality, but different for robustness and flexibility, which confirmed the importance to test the systems at industrial scale before acquiring the equipment.

  3. Radial localization of odors by human newborns.

    PubMed

    Rieser, J; Yonas, A; Wikner, K

    1976-09-01

    To study sensitivity to radial location of an odor source, 20 human newborns, ranging from 16 to 130 hours of age, were presented with a small amount of ammonium hydroxide. The odor source was placed near the nose slightly to the left or right of midline, with its position randomized over repeated trails. Direction of headturn with respect to the odor location and diffuse motor activity were scored from the videotape recordings of the newborns' behavior. It was found that as a group, the newborns turned away from the odor source more frequently than they turned toward it. The tendency to turn away from the odor was stronger in infants who displayed less motor activity after the response. Newborns also exhibited a right bias in the direction of the head movements. It is concluded that a spatially appropriate avoidance response is present in the neonate and that the newborn is innately sensitive to the radial location of an odor.

  4. Radial Inflow Turboexpander Redesign

    SciTech Connect

    William G. Price

    2001-09-24

    Steamboat Envirosystems, LLC (SELC) was awarded a grant in accordance with the DOE Enhanced Geothermal Systems Project Development. Atlas-Copco Rotoflow (ACR), a radial expansion turbine manufacturer, was responsible for the manufacturing of the turbine and the creation of the new computer program. SB Geo, Inc. (SBG), the facility operator, monitored and assisted ACR's activities as well as provided installation and startup assistance. The primary scope of the project is the redesign of an axial flow turbine to a radial inflow turboexpander to provide increased efficiency and reliability at an existing facility. In addition to the increased efficiency and reliability, the redesign includes an improved reduction gear design, and improved shaft seal design, and upgraded control system and a greater flexibility of application

  5. Variable stator radial turbine

    NASA Technical Reports Server (NTRS)

    Rogo, C.; Hajek, T.; Chen, A. G.

    1984-01-01

    A radial turbine stage with a variable area nozzle was investigated. A high work capacity turbine design with a known high performance base was modified to accept a fixed vane stagger angle moveable sidewall nozzle. The nozzle area was varied by moving the forward and rearward sidewalls. Diffusing and accelerating rotor inlet ramps were evaluated in combinations with hub and shroud rotor exit rings. Performance of contoured sidewalls and the location of the sidewall split line with respect to the rotor inlet was compared to the baseline. Performance and rotor exit survey data are presented for 31 different geometries. Detail survey data at the nozzle exit are given in contour plot format for five configurations. A data base is provided for a variable geometry concept that is a viable alternative to the more common pivoted vane variable geometry radial turbine.

  6. Radial pressure flange seal

    DOEpatents

    Batzer, Thomas H.; Call, Wayne R.

    1989-01-01

    This invention provides an all metal seal for vacuum or pressure vessels or systems. This invention does not use gaskets. The invention uses a flange which fits into a matching groove. Fluid pressure is applied in a chamber in the flange causing at least one of the flange walls to radially press against a side of the groove creating the seal between the flange wall and the groove side.

  7. Radial pressure flange seal

    DOEpatents

    Batzer, T.H.; Call, W.R.

    1989-01-24

    This invention provides an all metal seal for vacuum or pressure vessels or systems. This invention does not use gaskets. The invention uses a flange which fits into a matching groove. Fluid pressure is applied in a chamber in the flange causing at least one of the flange walls to radially press against a side of the groove creating the seal between the flange wall and the groove side. 5 figs.

  8. Radial Field Piezoelectric Diaphragms

    NASA Technical Reports Server (NTRS)

    Bryant, R. G.; Effinger, R. T., IV; Copeland, B. M., Jr.

    2002-01-01

    A series of active piezoelectric diaphragms were fabricated and patterned with several geometrically defined Inter-Circulating Electrodes "ICE" and Interdigitated Ring Electrodes "ICE". When a voltage potential is applied to the electrodes, the result is a radially distributed electric field that mechanically strains the piezoceramic along the Z-axis (perpendicular to the applied electric field). Unlike other piezoelectric bender actuators, these Radial Field Diaphragms (RFDs) strain concentrically yet afford high displacements (several times that of the equivalent Unimorph) while maintaining a constant circumference. One of the more intriguing aspects is that the radial strain field reverses itself along the radius of the RFD while the tangential strain remains relatively constant. The result is a Z-deflection that has a conical profile. This paper covers the fabrication and characterization of the 5 cm. (2 in.) diaphragms as a function of poling field strength, ceramic thickness, electrode type and line spacing, as well as the surface topography, the resulting strain field and displacement as a function of applied voltage at low frequencies. The unique features of these RFDs include the ability to be clamped about their perimeter with little or no change in displacement, the environmentally insulated packaging, and a highly repeatable fabrication process that uses commodity materials.

  9. Antiproton compression and radial measurements

    SciTech Connect

    Andresen, G. B.; Bowe, P. D.; Hangst, J. S.; Bertsche, W.; Butler, E.; Charlton, M.; Humphries, A. J.; Jenkins, M. J.; Joergensen, L. V.; Madsen, N.; Werf, D. P. van der; Bray, C. C.; Chapman, S.; Fajans, J.; Povilus, A.; Wurtele, J. S.; Cesar, C. L.; Lambo, R.; Silveira, D. M.; Fujiwara, M. C.

    2008-08-08

    Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report detailed measurements of the radial manipulation of antiproton clouds, including areal density compressions by factors as large as ten, achieved by manipulating spatially overlapped electron plasmas. We show detailed measurements of the near-axis antiproton radial profile, and its relation to that of the electron plasma. We also measure the outer radial profile by ejecting antiprotons to the trap wall using an octupole magnet.

  10. A Genetic-Based Feature Selection Approach in the Identification of Left/Right Hand Motor Imagery for a Brain-Computer Interface.

    PubMed

    Yaacoub, Charles; Mhanna, Georges; Rihana, Sandy

    2017-01-23

    Electroencephalography is a non-invasive measure of the brain electrical activity generated by millions of neurons. Feature extraction in electroencephalography analysis is a core issue that may lead to accurate brain mental state classification. This paper presents a new feature selection method that improves left/right hand movement identification of a motor imagery brain-computer interface, based on genetic algorithms and artificial neural networks used as classifiers. Raw electroencephalography signals are first preprocessed using appropriate filtering. Feature extraction is carried out afterwards, based on spectral and temporal signal components, and thus a feature vector is constructed. As various features might be inaccurate and mislead the classifier, thus degrading the overall system performance, the proposed approach identifies a subset of features from a large feature space, such that the classifier error rate is reduced. Experimental results show that the proposed method is able to reduce the number of features to as low as 0.5% (i.e., the number of ignored features can reach 99.5%) while improving the accuracy, sensitivity, specificity, and precision of the classifier.

  11. A Genetic-Based Feature Selection Approach in the Identification of Left/Right Hand Motor Imagery for a Brain-Computer Interface

    PubMed Central

    Yaacoub, Charles; Mhanna, Georges; Rihana, Sandy

    2017-01-01

    Electroencephalography is a non-invasive measure of the brain electrical activity generated by millions of neurons. Feature extraction in electroencephalography analysis is a core issue that may lead to accurate brain mental state classification. This paper presents a new feature selection method that improves left/right hand movement identification of a motor imagery brain-computer interface, based on genetic algorithms and artificial neural networks used as classifiers. Raw electroencephalography signals are first preprocessed using appropriate filtering. Feature extraction is carried out afterwards, based on spectral and temporal signal components, and thus a feature vector is constructed. As various features might be inaccurate and mislead the classifier, thus degrading the overall system performance, the proposed approach identifies a subset of features from a large feature space, such that the classifier error rate is reduced. Experimental results show that the proposed method is able to reduce the number of features to as low as 0.5% (i.e., the number of ignored features can reach 99.5%) while improving the accuracy, sensitivity, specificity, and precision of the classifier. PMID:28124985

  12. Radial Reflection diffraction tomorgraphy

    DOEpatents

    Lehman, Sean K

    2013-11-19

    A wave-based tomographic imaging method and apparatus based upon one or more rotating radially outward oriented transmitting and receiving elements have been developed for non-destructive evaluation. At successive angular locations at a fixed radius, a predetermined transmitting element can launch a primary field and one or more predetermined receiving elements can collect the backscattered field in a "pitch/catch" operation. A Hilbert space inverse wave (HSIW) algorithm can construct images of the received scattered energy waves using operating modes chosen for a particular application. Applications include, improved intravascular imaging, bore hole tomography, and non-destructive evaluation (NDE) of parts having existing access holes.

  13. Radial reflection diffraction tomography

    DOEpatents

    Lehman, Sean K.

    2012-12-18

    A wave-based tomographic imaging method and apparatus based upon one or more rotating radially outward oriented transmitting and receiving elements have been developed for non-destructive evaluation. At successive angular locations at a fixed radius, a predetermined transmitting element can launch a primary field and one or more predetermined receiving elements can collect the backscattered field in a "pitch/catch" operation. A Hilbert space inverse wave (HSIW) algorithm can construct images of the received scattered energy waves using operating modes chosen for a particular application. Applications include, improved intravascular imaging, bore hole tomography, and non-destructive evaluation (NDE) of parts having existing access holes.

  14. Fast radial flows in transition disk holes

    SciTech Connect

    Rosenfeld, Katherine A.; Andrews, Sean M.; Chiang, Eugene

    2014-02-20

    Protoplanetary 'transition' disks have large, mass-depleted central cavities, yet also deliver gas onto their host stars at rates comparable to disks without holes. The paradox of simultaneous transparency and accretion can be explained if gas flows inward at much higher radial speeds inside the cavity than outside the cavity, since surface density (and by extension optical depth) varies inversely with inflow velocity at fixed accretion rate. Radial speeds within the cavity might even have to approach free-fall values to explain the huge surface density contrasts inferred for transition disks. We identify observational diagnostics of fast radial inflow in channel maps made in optically thick spectral lines. Signatures include (1) twisted isophotes in maps made at low systemic velocities and (2) rotation of structures observed between maps made in high-velocity line wings. As a test case, we apply our new diagnostic tools to archival Atacama Large Millimeter Array data on the transition disk HD 142527 and uncover evidence for free-fall radial velocities inside its cavity. Although the observed kinematics are also consistent with a disk warp, the radial inflow scenario is preferred because it predicts low surface densities that appear consistent with recent observations of optically thin CO isotopologues in this disk. How material in the disk cavity sheds its angular momentum wholesale to fall freely onto the star is an unsolved problem; gravitational torques exerted by giant planets or brown dwarfs are briefly discussed as a candidate mechanism.

  15. Hypoplastic left heart syndrome

    MedlinePlus

    HLHS; Congenital heart - hypoplastic left heart; Cyanotic heart disease - hypoplastic left heart ... Hypoplastic left heart is a rare type of congenital heart disease. It is more common in males than in females. As ...

  16. Radial cold trap

    DOEpatents

    Grundy, Brian R.

    1981-01-01

    The radial cold trap comprises a housing having a plurality of mesh bands disposed therein. The mesh bands comprise concentrically arranged bands of mesh with the mesh specific surface area of each band increasing from the outermost mesh band to the innermost mesh band. An inlet nozzle is attached to the outside section of the housing while an outlet nozzle is attached to the inner portion of the housing so as to be concentrically connected to the innermost mesh band. An inlet baffle having orifices therein may be disposed around the outermost mesh band and within the housing for directing the flow of the fluid from the inlet nozzle to the outermost mesh band in a uniform manner. The flow of fluid passes through each consecutive mesh band and into the outlet nozzle. The circular pattern of the symmetrically arranged mesh packing allows for better utilization of the entire cold trap volume.

  17. Radial cold trap

    DOEpatents

    Grundy, B.R.

    1981-09-29

    The radial cold trap comprises a housing having a plurality of mesh bands disposed therein. The mesh bands comprise concentrically arranged bands of mesh with the mesh specific surface area of each band increasing from the outermost mesh band to the innermost mesh band. An inlet nozzle is attached to the outside section of the housing while an outlet nozzle is attached to the inner portion of the housing so as to be concentrically connected to the innermost mesh band. An inlet baffle having orifices therein may be disposed around the outermost mesh band and within the housing for directing the flow of the fluid from the inlet nozzle to the outermost mesh band in a uniform manner. The flow of fluid passes through each consecutive mesh band and into the outlet nozzle. The circular pattern of the symmetrically arranged mesh packing allows for better utilization of the entire cold trap volume. 2 figs.

  18. A fully relativistic radial fall

    NASA Astrophysics Data System (ADS)

    Spallicci, Alessandro D. A. M.; Ritter, Patxi

    2014-10-01

    Radial fall has historically played a momentous role. It is one of the most classical problems, the solutions of which represent the level of understanding of gravitation in a given epoch. A gedankenexperiment in a modern frame is given by a small body, like a compact star or a solar mass black hole, captured by a supermassive black hole. The mass of the small body itself and the emission of gravitational radiation cause the departure from the geodesic path due to the back-action, that is the self-force. For radial fall, as any other non-adiabatic motion, the instantaneous identity of the radiated energy and the loss of orbital energy cannot be imposed and provide the perturbed trajectory. In the first part of this paper, we present the effects due to the self-force computed on the geodesic trajectory in the background field. Compared to the latter trajectory, in the Regge-Wheeler, harmonic and all others smoothly related gauges, a far observer concludes that the self-force pushes inward (not outward) the falling body, with a strength proportional to the mass of the small body for a given large mass; further, the same observer notes a higher value of the maximal coordinate velocity, this value being reached earlier during infall. In the second part of this paper, we implement a self-consistent approach for which the trajectory is iteratively corrected by the self-force, this time computed on osculating geodesics. Finally, we compare the motion driven by the self-force without and with self-consistent orbital evolution. Subtle differences are noticeable, even if self-force effects have hardly the time to accumulate in such a short orbit.

  19. Radial access for cerebrovascular procedures: Case report and technical note

    PubMed Central

    Vance, Ansar Z; Sivapatham, Thinesh

    2015-01-01

    Background Advantages of radial access over brachial/axillary or femoral access have been well described for several decades and include decreased cost, patient preference, and decreased major access site complications. Despite these advantages, radial access is rarely employed or even considered for neurointerventional procedures. This attitude should be reconsidered given several recent large, randomized, controlled trials from the cardiovascular literature proving that radial access is associated with statistically lower costs, decreased incidence of myocardial infarctions, strokes, and even decreased mortality. Radial access is now considered the standard of care for percutaneous coronary interventions in most US centers. Although radial access has been described for neurovascular procedures in the past, overall experience is limited. The two major challenges are the unique anatomy required to access the cerebral vasculature given very acute angles between the arm and craniocervical vessels and limitations in available technology. Methods We present a simplified approach to radial access for cerebrovascular procedures and provide a concise step-by-step approach for patient selection, ultrasound-guided single-wall access, recommended catheters/wires, and review of patent hemostasis. Additionally, we present a complex cerebrovascular intervention in which standard femoral access was unsuccessful, while radial access was quickly achieved to highlight the importance of familiarity with the radial approach for all neurointerventionalists. Results We have found that the learning curve is not too steep and that the radial access approach can be adopted smoothly for a large percentage of diagnostic and interventional neuroradiologic procedures. Conclusions Radial access should be considered in all patients undergoing a cerebrovascular procedure. PMID:26659807

  20. Turbine with radial acting seal

    SciTech Connect

    Eng, Darryl S; Ebert, Todd A

    2016-11-22

    A floating brush seal in a rim cavity of a turbine in a gas turbine engine, where the floating brush seal includes a seal holder in which the floating brush seal floats, and a expandable seal that fits within two radial extending seal slots that maintains a seal with radial displacement of the floating brush seal and the seal holder.

  1. Radial systems of dark globules

    SciTech Connect

    Gyul'budagyn, A.L.

    1986-03-01

    The author gives examples of radial systems consisting of dark globules and ''elephant trunks''. Besides already known systems, which contain hot stars at their center, data are given on three radial systems of a new kind, at the center of which there are stars of spectral types later than B. Data are given on 32 globules of radial systems of the association Cep OB2. On the basis of the observational data, it is concluded that at least some of the isolated Bok globules derive from elephant trunks and dark globules forming radial systems around hot stars. It is also suggested that the two molecular clouds situated near the Rosette nebula and possessing velocities differing by ca 20 km/sec from the velocity of the nebula could have been ejected in opposite directions from the center of the nebula. One of these clouds consists of dark globules forming the radial system of the Rosette nebula.

  2. Metallic radial head arthroplasty improves valgus stability of the elbow.

    PubMed

    King, G J; Zarzour, Z D; Rath, D A; Dunning, C E; Patterson, S D; Johnson, J A

    1999-11-01

    The stabilizing influence of radial head arthroplasty was studied in eight medial collateral ligament deficient anatomic specimen elbows. An elbow testing apparatus, which used computer controlled pneumatic actuators to apply tendon loading, was used to simulate active elbow flexion. The motion pathways of the elbow were measured using an electromagnetic tracking device, with the forearm in supination and pronation. As a measure of stability, the maximum varus to valgus laxity over the range of elbow flexion was determined from the difference between varus and valgus gravity loaded motion pathways. After transection of the medial collateral ligament, the radial head was excised and replaced with either a silicone or one of three metallic radial head prostheses. Medial collateral ligament transection caused a significant increase in the maximum varus to valgus laxity to 18.0 degrees +/- 3.2 degrees. After radial head excision, this laxity increased to 35.6 degrees +/- 10.3 degrees. The silicone implant conferred no increase in elbow stability, with a maximum varus to valgus laxity of 32.5 degrees +/- 15.5 degrees. All three metallic implants improved the valgus stability of the medial collateral ligament deficient elbow, providing stability similar to the intact radial head. The use of silicone arthroplasty to replace the radial head in the medial collateral ligament deficient elbow must be questioned. Metallic radial head arthroplasty provides improved valgus stability, approaching that of an intact radial head.

  3. Computer Simulation of Radial Immunodiffusion

    PubMed Central

    Trautman, Rodes

    1972-01-01

    Theories of diffusion with chemical reaction are reviewed as to their contributions toward developing an algorithm needed for computer simulation of immunodiffusion. The Spiers-Augustin moving sink and the Engelberg stationary sink theories show how the antibody-antigen reaction can be incorporated into boundary conditions of the free diffusion differential equations. For this, a stoichiometric precipitate was assumed and the location of precipitin lines could be predicted. The Hill simultaneous linear adsorption theory provides a mathematical device for including another special type of antibody-antigen reaction in antigen excess regions of the gel. It permits an explanation for the lowered antigen diffusion coefficient, observed in the Oudin arrangement of single linear diffusion, but does not enable prediction of the location of precipitin lines. The most promising mathematical approach for a general solution is implied in the Augustin alternating cycle theory. This assumes the immunodiffusion process can be evaluated by alternating computation cycles: free diffusion without chemical reaction and chemical reaction without diffusion. The algorithm for the free diffusion update cycle, extended to both linear and radial geometries, is given in detail since it was based on gross flow rather than more conventional expressions in terms of net flow. Limitations on the numerical integration process using this algorithm are illustrated for free diffusion from a cylindrical well. PMID:4629869

  4. Radially sandwiched cylindrical piezoelectric transducer

    NASA Astrophysics Data System (ADS)

    Lin, Shuyu; Fu, Zhiqiang; Zhang, Xiaoli; Wang, Yong; Hu, Jing

    2013-01-01

    A new type of radially sandwiched piezoelectric short cylindrical transducer is developed and its radial vibration is studied. The transducer is composed of a solid metal disk, a radially polarized piezoelectric ceramic short tube and a metal tube. The radial vibrations of the solid metal disk, the radially polarized piezoelectric tube and the metal tube are analyzed and their electromechanical equivalent circuits are introduced. Based on the mechanical boundary conditions among the metal disk, the piezoelectric tube and the metal tube, a three-port electromechanical equivalent circuit for the radially sandwiched transducer is obtained and the frequency equation is given. The theoretical relationship of the resonance and anti-resonance frequencies and the effective electromechanical coupling coefficient with the geometrical dimensions is analyzed. The radial vibration of the sandwiched transducer is simulated by using two different numerical methods. It is shown that the analytical resonance and anti-resonance frequencies are in good agreement with the numerically simulated results. The transducer is expected to be used in piezoelectric resonators, actuators and ultrasonic radiators in ultrasonic and underwater sound applications.

  5. An alternative percutaneous interventional approach for post-anastomatic left anterior descending artery stenosis in patients with markedly tortuous LIMA graft.

    PubMed

    Tengiz, Istemihan; Aliyev, Emil; Ercan, Ertugrul

    2005-10-01

    Percutaneous coronary intervention through a tortuous left internal mammary artery (LIMA) graft, especially with redundancy in length is a challenge in spite of availability of different types of coated guidewires and low-profile balloons. Various modifications of the interventional technique are required in order to negotiate the tortuosity of the LIMA graft. We describe an alternative technique that overcomes this problem in patient with a markedly tortuous LIMA graft.

  6. Left ventricular bronchogenic cyst.

    PubMed

    Wei, Xiang; Omo, Alfred; Pan, Tiecheng; Li, Jun; Liu, Ligang; Hu, Min

    2006-04-01

    Bronchogenic cysts occurring in the left ventricle are a medical rarity. One successfully operated case is reported herein. The location of the cyst was just between the epicardium and myocardium of the inferior left ventricular wall, adjacent to the apex of the heart. Complete excision was achieved through a left anterolateral thoracotomy without extracorporeal circulation.

  7. Spontaneous Reduction of a Chronic Radial Head Subluxation after open Reduction and Percutaneous Pin Fixation of a Radial Neck Fracture: A Case Report and Review of the Literature

    PubMed Central

    Illingworth, Kenneth David; Thompson, Kirk; Lovell, Matthew; McGinty, Jasmin

    2013-01-01

    Background Fractures of the radial neck in children have shown to account for 5-10% of traumatic elbow injuries in the pediatric population. Chronic dislocation of the radial head with concomitant fracture has been shown to result in progressive deformity and unacceptable loss of motion. Methods In this case report, we describe a patient who sustained a type 2 radial neck fracture with 100% displacement. The patient’s clinical and surgical management will be discussed and a review of the literature is provided as it relates to this particular case. Results The patient underwent open reduction and percutaneous pin fixation of her displaced, dislocated left radial neck fracture in the operating room after multiple failed attempts at closed reduction due to interposition of the annular ligament. Three months after her operation radiographs revealed a well-healed radial neck with no signs of avascular necrosis with an anterior dislocation of her radial head, which was a new finding from her previous radiographs. Fourteen months after her initial injury and operation, radiographs taken at this visit revealed a radial neck fracture that was completely remodeled and had spontaneous relocated and was now aligned with the capitellum without any reduction attempt. Conclusion Closed reduction of displaced radial neck fractures may be unsuccessful and open reduction may be warranted. Excess callus formation post-operatively may have resulted in the radial head subluxation; however there was spontaneous reduction with conservative treatment without a reduction attempt, most likely related to remodeling of the excel callus formation. PMID:24027488

  8. Flipped versions of the universal 3-3-1 and the left-right symmetric models in [S U (3 )]3 : A comprehensive approach

    NASA Astrophysics Data System (ADS)

    Rodríguez, Oscar; Benavides, Richard H.; Ponce, William A.; Rojas, Eduardo

    2017-01-01

    By considering the 3-3-1 and the left-right symmetric models as low-energy effective theories of the S U (3 )C⊗S U (3 )L⊗S U (3 )R (for short [S U (3 )]3 ) gauge group, alternative versions of these models are found. The new neutral gauge bosons of the universal 3-3-1 model and its flipped versions are presented; also, the left-right symmetric model and its flipped variants are studied. Our analysis shows that there are two flipped versions of the universal 3-3-1 model, with the particularity that both of them have the same weak charges. For the left-right symmetric model, we also found two flipped versions; one of them is new in the literature and, unlike those of the 3-3-1, requires a dedicated study of its electroweak properties. For all the models analyzed, the couplings of the Z' bosons to the standard model fermions are reported. The explicit form of the null space of the vector boson mass matrix for an arbitrary Higgs tensor and gauge group is also presented. In the general framework of the [S U (3 )]3 gauge group, and by using the LHC experimental results and EW precision data, limits on the Z' mass and the mixing angle between Z and the new gauge bosons Z' are obtained. The general results call for very small mixing angles in the range 1 0-3 radians and MZ'>2.5 TeV .

  9. Angiologic observations following radial artery flap elevation: a case report.

    PubMed

    Ciria-Lloréns, G; Gómez-Cía, T; Talegón-Meléndez, A

    1998-01-01

    Since the introduction of the radial forearm flap in 1981, its inherent vascular morbidity in sacrificing the radial artery has been strongly criticized. In the present paper, a case report is presented where postoperative angiography showed an important contribution of the anterior interosseous artery to hand vascularity two years after raising a reverse flow distally based pedicle radial forearm flap for dorsal hand resurfacing. In order to analyze this finding, further vascular investigations using Color Duplex Imaging examinations for quantitative flow measurements comparing blood flow rates in both right and left forearm arteries were carried out in this patient. Contrary to expectations, results from vascular examinations revealed that overall blood flow in donor forearm arteries was greater than in the contralateral forearm, the anterior interosseous artery showing the greatest difference in blood flow. These data seem to indicate that another major vascular axis based on the anterior interosseous artery develops after removing the radial artery when harvesting the radial forearm flap and that global arterial inflow to the hand is not impaired.

  10. Radial lean direct injection burner

    DOEpatents

    Khan, Abdul Rafey; Kraemer, Gilbert Otto; Stevenson, Christian Xavier

    2012-09-04

    A burner for use in a gas turbine engine includes a burner tube having an inlet end and an outlet end; a plurality of air passages extending axially in the burner tube configured to convey air flows from the inlet end to the outlet end; a plurality of fuel passages extending axially along the burner tube and spaced around the plurality of air passage configured to convey fuel from the inlet end to the outlet end; and a radial air swirler provided at the outlet end configured to direct the air flows radially toward the outlet end and impart swirl to the air flows. The radial air swirler includes a plurality of vanes to direct and swirl the air flows and an end plate. The end plate includes a plurality of fuel injection holes to inject the fuel radially into the swirling air flows. A method of mixing air and fuel in a burner of a gas turbine is also provided. The burner includes a burner tube including an inlet end, an outlet end, a plurality of axial air passages, and a plurality of axial fuel passages. The method includes introducing an air flow into the air passages at the inlet end; introducing a fuel into fuel passages; swirling the air flow at the outlet end; and radially injecting the fuel into the swirling air flow.

  11. Management of radial artery perforation during transradial catheterization using a polytetrafluoroethylene-covered coronary stent.

    PubMed

    Chatterjee, Arka; White, Jeremy S; Leesar, Massoud A

    2017-03-01

    An 88-year-old woman underwent attempted percutaneous coronary intervention (PCI) through a right radial approach. Catheterization was complicated by radial artery perforation. Conservative therapeutic options including external compression, advancement of a diagnostic catheter distal to the perforation, and balloon tamponade failed to control the bleeding requiring deployment of a Polytetrafluoroethylene (PTFE)-covered stent to seal the perforation. We describe the stepwise approach advocated for managing a radial perforation and summarize relevant literature available for the same.

  12. Losses in radial inflow turbines

    NASA Technical Reports Server (NTRS)

    Khalil, I. M.; Tabakoff, W.; Hamed, A.

    1976-01-01

    A study was conducted to determine experimentally and theoretically the losses in radial inflow turbine nozzles. Extensive experimental data was obtained to investigate the flow behavior in a full-scale radial turbine stator annulus. A theoretical model to predict the losses in both the vaned and vaneless regions of the nozzle was developed. In this analysis, the interaction effects between the stator and the rotor are not considered. It was found that the losses incurred due to the end wall boundary layers can be significant, especially if they are characterized by a strong crossflow. The losses estimated using the analytical study are compared with the experimentally determined values.

  13. A combined deep-learning and deformable-model approach to fully automatic segmentation of the left ventricle in cardiac MRI.

    PubMed

    Avendi, M R; Kheradvar, Arash; Jafarkhani, Hamid

    2016-05-01

    Segmentation of the left ventricle (LV) from cardiac magnetic resonance imaging (MRI) datasets is an essential step for calculation of clinical indices such as ventricular volume and ejection fraction. In this work, we employ deep learning algorithms combined with deformable models to develop and evaluate a fully automatic LV segmentation tool from short-axis cardiac MRI datasets. The method employs deep learning algorithms to learn the segmentation task from the ground true data. Convolutional networks are employed to automatically detect the LV chamber in MRI dataset. Stacked autoencoders are used to infer the LV shape. The inferred shape is incorporated into deformable models to improve the accuracy and robustness of the segmentation. We validated our method using 45 cardiac MR datasets from the MICCAI 2009 LV segmentation challenge and showed that it outperforms the state-of-the art methods. Excellent agreement with the ground truth was achieved. Validation metrics, percentage of good contours, Dice metric, average perpendicular distance and conformity, were computed as 96.69%, 0.94, 1.81 mm and 0.86, versus those of 79.2-95.62%, 0.87-0.9, 1.76-2.97 mm and 0.67-0.78, obtained by other methods, respectively.

  14. Vortex Whistle in Radial Intake

    DTIC Science & Technology

    2004-10-01

    RTO-MP-AVT-110 22 - 1 Vortex Whistle in Radial Intake Dr. Man-Chun Tse Pratt & Whitney Canada Corp. 1000 Marie-Victorin, Longueuil , Quebec...ORGANIZATION NAME(S) AND ADDRESS(ES) Pratt & Whitney Canada Corp. 1000 Marie-Victorin, Longueuil , Quebec, Canada, J4G 1A1 8. PERFORMING ORGANIZATION REPORT

  15. Combining Transit and Radial Velocity Data

    NASA Astrophysics Data System (ADS)

    Rogers, Leslie A.

    2016-10-01

    The Kepler Mission, combined with ground based radial velocity (RV) follow-up, has revolutionized the observational constraints on sub-Neptune-size planet compositions. Kepler's unprecedentedly large and homogeneous samples of planets with both mass and radius constraints open the possibility of statistical studies of the underlying planet composition distribution. This presentation describes the application of hierarchical Bayesian models to constrain the underlying planet composition distribution from a sample of noisy mass-radius measurements. This approach represents a promising avenue toward a quantitative measurement of the amount of physical scatter in small planet compositions, the identification of planet sub-populations that may be tied to distinct formation pathways, and empirical constraints on the dominant compositional trends in the planet sample. Both the transit and radial velocity techniques are subject to selection effects, and approaches to mitigate the resulting biases will be addressed. In addition to distilling composition-distribution insights from the current sample of Kepler planets with RV masses, this framework may be used to optimize the target selection for future transiting planet RV follow-up surveys.

  16. Radial Velocity Eclipse Mapping of Exoplanets

    NASA Astrophysics Data System (ADS)

    Nikolov, Nikolay; Sainsbury-Martinez, Felix

    2015-07-01

    Planetary rotation rates and obliquities provide information regarding the history of planet formation, but have not yet been measured for evolved extrasolar planets. Here we investigate the theoretical and observational perspective of the Rossiter-McLaughlin effect during secondary eclipse (RMse) ingress and egress for transiting exoplanets. Near secondary eclipse, when the planet passes behind the parent star, the star sequentially obscures light from the approaching and receding parts of the rotating planetary surface. The temporal block of light emerging from the approaching (blueshifted) or receding (redshifted) parts of the planet causes a temporal distortion in the planet’s spectral line profiles resulting in an anomaly in the planet’s radial velocity curve. We demonstrate that the shape and the ratio of the ingress-to-egress radial velocity amplitudes depends on the planetary rotational rate, axial tilt, and impact factor (i.e., sky-projected planet spin-orbital alignment). In addition, line asymmetries originating from different layers in the atmosphere of the planet could provide information regarding zonal atmospheric winds and constraints on the hot spot shape for giant irradiated exoplanets. The effect is expected to be most-pronounced at near-infrared wavelengths, where the planet-to-star contrasts are large. We create synthetic near-infrared, high-dispersion spectroscopic data and demonstrate how the sky-projected spin axis orientation and equatorial velocity of the planet can be estimated. We conclude that the RMse effect could be a powerful method to measure exoplanet spins.

  17. RADIAL VELOCITY ECLIPSE MAPPING OF EXOPLANETS

    SciTech Connect

    Nikolov, Nikolay; Sainsbury-Martinez, Felix

    2015-07-20

    Planetary rotation rates and obliquities provide information regarding the history of planet formation, but have not yet been measured for evolved extrasolar planets. Here we investigate the theoretical and observational perspective of the Rossiter–McLaughlin effect during secondary eclipse (RMse) ingress and egress for transiting exoplanets. Near secondary eclipse, when the planet passes behind the parent star, the star sequentially obscures light from the approaching and receding parts of the rotating planetary surface. The temporal block of light emerging from the approaching (blueshifted) or receding (redshifted) parts of the planet causes a temporal distortion in the planet’s spectral line profiles resulting in an anomaly in the planet’s radial velocity curve. We demonstrate that the shape and the ratio of the ingress-to-egress radial velocity amplitudes depends on the planetary rotational rate, axial tilt, and impact factor (i.e., sky-projected planet spin–orbital alignment). In addition, line asymmetries originating from different layers in the atmosphere of the planet could provide information regarding zonal atmospheric winds and constraints on the hot spot shape for giant irradiated exoplanets. The effect is expected to be most-pronounced at near-infrared wavelengths, where the planet-to-star contrasts are large. We create synthetic near-infrared, high-dispersion spectroscopic data and demonstrate how the sky-projected spin axis orientation and equatorial velocity of the planet can be estimated. We conclude that the RMse effect could be a powerful method to measure exoplanet spins.

  18. Lynch syndrome-associated colorectal carcinoma: frequent involvement of the left colon and rectum and late-onset presentation supports a universal screening approach.

    PubMed

    Hartman, Douglas J; Brand, Randall E; Hu, Huankai; Bahary, Nathan; Dudley, Beth; Chiosea, Simon I; Nikiforova, Marina N; Pai, Reetesh K

    2013-11-01

    The optimal strategy for screening patients with colorectal carcinoma for Lynch syndrome (LS) is a subject of continued debate in the literature with some advocating universal screening while others arguing for selective screening. We evaluated 1292 colorectal carcinomas for DNA mismatch repair protein abnormalities and identified 150 (11.6%) tumors demonstrating high-levels of microsatellite instability (MSI-H). MSI-H colorectal carcinomas were divided into sporadic (112/1292, 8.7%) and LS/probable LS-associated (38/1292, 2.9%) groups based on BRAF V600E mutation, MLH1 promoter hypermethylation, cancer history, and germline mismatch repair gene mutation. All MSI-H colorectal carcinomas were analyzed for grade, location, and tumor histology. The utility of the revised Bethesda guidelines and published predictive pathology models for MSI-H colorectal carcinomas (PREDICT and MSPath) were evaluated. Left-sided MSI-H colorectal carcinomas were more frequently associated with LS compared with right-sided MSI-H colorectal carcinomas (12/21, 57% versus 26/129, 20%, P = .0008). There was no significant difference in histology between sporadic MSI-H and LS/probable LS-associated colorectal carcinomas except for a slightly higher proportion of sporadic MSI-H tumors demonstrating tumor-infiltrating lymphocytes (81% versus 61%, P = .015). Neither pathology predictive model identified all LS-associated colorectal carcinomas (PREDICT: 33/38, 87%; MSPath: 35/38, 92%). 12/117 (10%) MSI-H colorectal carcinomas identified in patients >60 years were LS/probable LS-associated. Our results demonstrate that models of predicting MSI-H fail to identify LS-associated colorectal carcinoma given their reliance on right-sided location. A significant proportion (32%) of LS-associated colorectal carcinoma is identified in patients >60 years. Finally, our results demonstrate similar morphologic features between LS-associated and sporadic MSI-H colorectal carcinomas.

  19. Causes of Secondary Radial Nerve Palsy and Results of Treatment

    PubMed Central

    Reichert, Paweł; Wnukiewicz, Witold; Witkowski, Jarosław; Bocheńska, Aneta; Mizia, Sylwia; Gosk, Jerzy; Zimmer, Krzysztof

    2016-01-01

    Background The aim of this study was to analyze the causes that lead to secondary damage of the radial nerve and to discuss the results of reconstructive treatment. Material/Methods The study group consisted of 33 patients treated for radial nerve palsy after humeral fractures. Patients were diagnosed based on clinical examinations, ultrasonography, electromyography, or nerve conduction velocity. During each operation, the location and type of nerve damage were analyzed. During the reconstructive treatment, neurolysis, direct neurorrhaphy, or reconstruction with a sural nerve graft was used. The outcomes were evaluated using the Medical Research Council (MRC) scales and the quick DASH score. Results Secondary radial nerve palsy occurs after open reduction and internal fixation (ORIF) by plate, as well as by closed reduction and internal fixation (CRIF) by nail. In the case of ORIF, it most often occurs when the lateral approach is used, as in the case of CRIF with an insertion interlocking screws. The results of the surgical treatment were statistically significant and depended on the time between nerve injury and revision (reconstruction) surgery, type of damage to the radial nerve, surgery treatment, and type of fixation. Treatment results were not statistically significant, depending on the type of fracture or location of the nerve injury. Conclusions The potential risk of radial nerve neurotmesis justifies an operative intervention to treat neurological complications after a humeral fracture. Adequate surgical treatment in many of these cases allows for functional recovery of the radial nerve. PMID:26895570

  20. Optimal design of radial Bragg cavities and lasers.

    PubMed

    Ben-Bassat, Eyal; Scheuer, Jacob

    2015-07-01

    We present a new and optimal design approach for obtaining maximal confinement of the field in radial Bragg cavities and lasers for TM polarization. The presented approach outperforms substantially the previously employed periodic and semi-periodic design schemes of such lasers. We show that in order to obtain maximal confinement, it is essential to consider the complete reflection properties (amplitude and phase) of the propagating radial waves at the interfaces between Bragg layers. When these properties are taken into account, we find that it is necessary to introduce a wider ("half-wavelength") layer at a specific radius in the "quarter-wavelength" radial Bragg stack. It is shown that this radius corresponds to the cylindrical equivalent of Brewster's angle. The confinement and field profile are calculated numerically by means of transfer matrix method.

  1. Left heart catheterization

    MedlinePlus

    Catheterization - left heart ... to help guide the catheters up into your heart and arteries. Dye (sometimes called "contrast") will be ... in the blood vessels that lead to your heart. The catheter is then moved through the aortic ...

  2. Left Ventricular Hypertrophy

    MedlinePlus

    ... at the time of their diagnosis with hypertension. Aortic valve stenosis. This disease is a narrowing of the tissue ... muscle and disease. In addition to hypertension and aortic valve stenosis, factors that increase your risk for left ventricular ...

  3. Left Atrial Myxoma

    DTIC Science & Technology

    2006-09-01

    enhanced pulmonary CT angiogram demonstrated normal pulmonary arteries (i.e. no pulmonary embolus) and confirmed the presence of left-sided pulmonary ... arteries without evidence for pulmonary embolism but note of patchy airspace disease within the left upper and lower lobes (Figure 1C), which...1A) and lateral (Figure 1B) chest radiographs were obtained and the patient also underwent a contrast-enhanced pulmonary CT angiogram (CTA; Figure

  4. En bloc aortic and mitral valve replacement and left ventricular outflow tract enlargement using a combined transaortic and trans-septal atrial approach.

    PubMed

    Hassan, Mohammed; Windsor, Jimmy; Ricci, Marco

    2015-12-01

    Aortic and mitral valve replacement with division and reconstruction of the inter-valvular fibrous body has been described in clinical situations involving infective endocarditis, extensive annular calcifications and diminutive valve annuli. Herein, we describe a combined transaortic and trans-septal approach with division of the inter-valvular fibrosa for combined aortic and mitral valve replacement. The reconstruction of the inter-valvular fibrous body, atrial walls and aortic root was carried out using a 'three-patch' technique with bovine pericardium.

  5. Functional connectivity of the left and right hippocampi: Evidence for functional lateralization along the long-axis using meta-analytic approaches and ultra-high field functional neuroimaging.

    PubMed

    Robinson, Jennifer L; Salibi, Nouha; Deshpande, Gopikrishna

    2016-07-15

    Theories regarding the functional specialization of the hippocampus date back to over a century ago. Two main theories have dominated the field. First, evidence has supported the notion of hemispheric specialization, which appears to be preserved across species. Second, an emergent and mounting set of data has suggested an anterior-posterior neurofunctional gradient. However, no study has examined these theories, and their potential interaction, using objective, robust methodological approaches. Here, we employed an established meta-analytic technique and use ultra-high field, high-resolution functional and structural neuroimaging to examine hippocampal lateralization with consideration for a long-axis differentiation. Data revealed strong support for an evolutionarily preserved hemispheric specialization. Specifically, we found intra- and interhemispheric differences with regard to anterior and posterior functional and structural connectivity, between the right and left hippocampi. For task-independent functional connectivity, we found the right anterior hippocampus to have functional connectivity with a large, distributed network, whereas the left anterior hippocampus demonstrated primarily fronto-limbic connectivity. These patterns were reversed for the posterior segmentations. Not surprisingly, for task-dependent connectivity, we found interhemispheric differences within key ipsilateral structures (i.e., parahippocampal gyrus) for both anterior and posterior segmentations. Furthermore, we identified pivotal neural hubs that share connectivity across behavioral domains, and are supported by structural connectivity (i.e., posterior cingulate cortex). Thus, our data provide evidence for a hemisphere-specific, anterior-posterior specialization of the hippocampal formation.

  6. Velocidades radiales en Collinder 121

    NASA Astrophysics Data System (ADS)

    Arnal, M.; Morrell, N.

    Se han llevado a cabo observaciones espectroscópicas de unas treinta estrellas que son posibles miembros del cúmulo abierto Collinder 121. Las mismas fueron realizadas con el telescopio de 2.15m del Complejo Astronómico El Leoncito (CASLEO). El análisis de las velocidades radiales derivadas del material obtenido, confirma la realidad de Collinder 121, al menos desde el punto de vista cinemático. La velocidad radial baricentral (LSR) del cúmulo es de +17 ± 3 km.s-1. Esta velocidad coincide, dentro de los errores, con la velocidad radial (LSR) de la nebulosa anillo S308, la cual es de ~20 ± 10 km.s-1. Como S308 se encuentra físicamente asociada a la estrella Wolf-Rayet HD~50896, es muy probable que esta última sea un miembro de Collinder 121. Desde un punto de vista cinemático, la supergigante roja HD~50877 (K3Iab) también pertenecería a Collinder 121. Basándonos en la pertenencia de HD~50896 a Collinder 121, y en la interacción encontrada entre el viento de esta estrella y el medio interestelar circundante a la misma, se estima para este cúmulo una distancia del orden de 1 kpc.

  7. Left colectomy with intracoporeal anastomosis: technical aspects

    PubMed Central

    Araujo, Sérgio Eduardo Alonso; Seid, Victor Edmond; Klajner, Sidney; Bertoncini, Alexandre Bruno

    2014-01-01

    Oncologic laparoscopic colectomy represents a fully validated surgical approach to the management of colorectal cancer. However, laparoscopic surgery for distal transverse and descending colon lesions remains a challenging procedure. A total laparoscopic approach to the left colectomy is an interesting option for critically ill patients although reports in the literature on this subject are scarce and its approach still not standardized because of its selective nature for indication. There are several advantages associated with conduction of totally laparoscopic approach to the left colon. Intracorporeal vessel sealing ensures an adequate lymph node dissection. Moreover, it enables the construction of a well-vascularized anastomosis. Ultimately, the occurrence of late wound complications are possibly reduced for the placement of a low abdominal incision exclusively used for specimen extraction. This paper aimed at describing our technique for a totally laparoscopic left colectomy for distal transverse and descending colon lesions. PMID:25295460

  8. Radiation Dose Reduction during Radial Cardiac Catheterization: Evaluation of a Dedicated Radial Angiography Absorption Shielding Drape.

    PubMed

    Ertel, Andrew; Nadelson, Jeffrey; Shroff, Adhir R; Sweis, Ranya; Ferrera, Dean; Vidovich, Mladen I

    2012-01-01

    Objectives. Radiation scatter protection shield drapes have been designed with the goal of decreasing radiation dose to the operators during transfemoral catheterization. We sought to investigate the impact on operator radiation exposure of various shielding drapes specifically designed for the radial approach. Background. Radial access for cardiac catheterization has increased due to improved patient comfort and decreased bleeding complications. There are concerns for increased radiation exposure to patients and operators. Methods. Radiation doses to a simulated operator were measured with a RadCal Dosimeter in the cardiac catheterization laboratory. The mock patient was a 97.5 kg fission product phantom. Three lead-free drape designs were studied. The drapes were placed just proximal to the right wrist and extended medially to phantom's trunk. Simulated diagnostic coronary angiography included 6 minutes of fluoroscopy time and 32 seconds of cineangiography time at 4 standard angulated views (8 s each), both 15 frames/s. ANOVA with Bonferroni correction was used for statistical analysis. Results. All drape designs led to substantial reductions in operator radiation exposure compared to control (P < 0.0001). The greatest decrease in radiation exposure (72%) was with the L-shaped design. Conclusions. Dedicated radial shielding drapes decrease radiation exposure to the operator by up to 72% during simulated cardiac catheterization.

  9. Asymmetry of Radial and Symmetry of Tangential Neuronal Migration Pathways in Developing Human Fetal Brains.

    PubMed

    Miyazaki, Yuta; Song, Jae W; Takahashi, Emi

    2016-01-01

    The radial and tangential neural migration pathways are two major neuronal migration streams in humans that are critical during corticogenesis. Corticogenesis is a complex process of neuronal proliferation that is followed by neuronal migration and the formation of axonal connections. Existing histological assessments of these two neuronal migration pathways have limitations inherent to microscopic studies and are confined to small anatomic regions of interest (ROIs). Thus, little evidence is available about their three-dimensional (3-D) fiber pathways and development throughout the entire brain. In this study, we imaged and analyzed radial and tangential migration pathways in the whole human brain using high-angular resolution diffusion MR imaging (HARDI) tractography. We imaged ten fixed, postmortem fetal (17 gestational weeks (GW), 18 GW, 19 GW, three 20 GW, three 21 GW and 22 GW) and eight in vivo newborn (two 30 GW, 34 GW, 35 GW and four 40 GW) brains with no neurological/pathological conditions. We statistically compared the volume of the left and right radial and tangential migration pathways, and the volume of the radial migration pathways of the anterior and posterior regions of the brain. In specimens 22 GW or younger, the volume of radial migration pathways of the left hemisphere was significantly larger than that of the right hemisphere. The volume of posterior radial migration pathways was also larger when compared to the anterior pathways in specimens 22 GW or younger. In contrast, no significant differences were observed in the radial migration pathways of brains older than 22 GW. Moreover, our study did not identify any significant differences in volumetric laterality in the tangential migration pathways. These results suggest that these two neuronal migration pathways develop and regress differently, and radial neuronal migration varies regionally based on hemispheric and anterior-posterior laterality, potentially explaining regional differences in

  10. Topographical anatomy of the radial nerve and its muscular branches related to surface landmarks.

    PubMed

    Cho, Hyejin; Lee, Hye-Yeon; Gil, Young-Chun; Choi, Yun-Rak; Yang, Hee-Jun

    2013-10-01

    Understanding of the anatomy of the radial nerve and its branches is vital to the treatment of humeral fracture or the restoration of upper extremity function. In this study, we dissected 40 upper extremities from adult cadavers to locate the course of the radial nerve and the origins and insertions of the branches of the radial nerve using surface landmarks. The radial nerve reached and left the radial groove and pierced the lateral intermuscular septum, at the levels of 46.7, 60.5, and 66.8% from the acromion to the transepicondylar line, respectively. Branches to the long head of the triceps brachii originated in the axilla, and branches to the medial and lateral heads originated in the axilla or in the arm. The muscular attachments to the long, medial, and lateral heads were on average 34.0 mm proximal, 16.4 mm distal, and 19.3 mm proximal to the level of inferior end of the deltoid muscle, respectively. The radial nerve innervated 65.0% of the brachialis muscles. Branches to the brachioradialis and those to the extensor carpi radialis longus arose from the radial nerve above the transepicondylar line. Branches to the extensor carpi radialis brevis usually arose from the deep branch of radial nerve (67.5%); however, in some cases, branches to the extensor carpi radialis brevis arose from either the radial nerve (20.0%) or the superficial branch of the radial nerve (12.5%). Using these data, the course of the radial nerve can be estimated by observing the surface of the arm.

  11. Dropwise Condensation on a Radial Gradient Surface

    NASA Astrophysics Data System (ADS)

    Macner, Ashley; Daniel, Susan; Steen, Paul

    2013-11-01

    In transient dropwise condensation from steam onto a cool surface, distributions of drops evolve by nucleation, growth, and coalescence. This study examines how surface functionalization affects drop growth and coalescence. Surfaces are treated by silanization to deliver either a spatially uniform contact-angle (hydrophilic, neutral, and hydrophobic) or a radial gradient of contact-angles. The time evolution of number-density and associated drop-size distributions are reported. For a typical condensation experiment on a uniform angle surface, the number-density curves show two regimes: an initial increase in number-density as a result of nucleation and a subsequent decrease in number-density as a result of larger scale coalescence events. Without a removal mechanism, the fractional coverage, regardless of treatment, approaches unity. For the same angle-surface, the associated drop-size distributions progress through four different shapes along the growth curve. In contrast, for a radial gradient surface where removal by sweeping occurs, the number-density increases and then levels off to a value close to the maximum number-density that is well below unity coverage and only two shapes of distributions are observed. Implications for heat transfer will be discussed. This work was supported by a NASA Office of the Chief Technologist's Space Technology Research Fellowship.

  12. Hypoplastic left heart syndrome (image)

    MedlinePlus

    Hypoplastic left heart syndrome is a congenital heart condition that occurs during the development of the heart in the ... womb. During the heart's development, parts of the left side of the heart (mitral valve, left ventricle ...

  13. Applied anatomy of the superficial branch of the radial nerve.

    PubMed

    Robson, A J; See, M S; Ellis, H

    2008-01-01

    The superficial branch of the radial nerve (SBRN) is highly vulnerable to trauma and iatrogenic injury. This study aimed to map the course of the SBRN in the context of surgical approaches and identify a safe area of incision for de Quervain's tenosynovitis. Twenty-five forearms were dissected. The SBRN emerged from under brachioradialis by a mean of 8.31 cm proximal to the radial styloid (RS), and remained radial to the dorsal tubercle of the radius by a mean of 1.49 cm. The nerve divided into a median of four branches. The first branch arose a mean of 4.92 cm proximal to the RS, traveling 0.49 cm radial to the first compartment of the extensor retinaculum, while the main nerve remained ulnar to it by 0.64 cm. All specimens had branches underlying the traditional transverse incision for de Quervain's release. A 2.5-cm longitudinal incision proximal from the RS avoided the SBRN in 17/25 cases (68%). In 20/25 specimens (80%), the SBRN underlay the cephalic vein. In 18/25 (72%), the radial artery was closely associated with a sensory nerve branch near the level of the RS (SBRN 12/25, lateral cutaneous nerve of the forearm (LCNF) 6/25.) A longitudinal incision in de Quervain's surgery may be preferable. Cannulation of the cephalic vein in the distal third of the forearm is best avoided. The close association between the radial artery and first branch of the SBRN or the LCNF may explain the pain often experienced during arterial puncture. Particular care should be taken during radial artery harvest to avoid nerve injury.

  14. Radial tears of the menisci: MR findings.

    PubMed

    Tuckman, G A; Miller, W J; Remo, J W; Fritts, H M; Rozansky, M I

    1994-08-01

    Radial meniscal tears have a plane of cleavage oriented across the short axis of the meniscus in the same plane in which radial images are oriented. These tears are important to recognize, because they have clinical implications different from those of other meniscal tears with respect to meniscal function, orthopedic treatment, and clinical course. Depending on their size, location, and orientation, radial tears can have different appearances on standard MR images. Certain types can be fairly subtle to diagnose. The purpose of this essay is to illustrate the varied appearances of radial tears on MR images and the findings commonly associated with radial tears.

  15. Radial propagation of geodesic acoustic modes

    SciTech Connect

    Hager, Robert; Hallatschek, Klaus

    2009-07-15

    The GAM group velocity is estimated from the ratio of the radial free energy flux to the total free energy applying gyrokinetic and two-fluid theory. This method is much more robust than approaches that calculate the group velocity directly and can be generalized to include additional physics, e.g., magnetic geometry. The results are verified with the gyrokinetic code GYRO[J. Candy and R. E. Waltz, J. Comput. Phys. 186, 545 (2003)], the two-fluid code NLET[K. Hallatschek and A. Zeiler, Phys. Plasmas 7, 2554 (2000)], and analytical calculations. GAM propagation must be kept in mind when discussing the windows of GAM activity observed experimentally and the match between linear theory and experimental GAM frequencies.

  16. Radially dependent angular acceleration of twisted light.

    PubMed

    Webster, Jason; Rosales-Guzmán, Carmelo; Forbes, Andrew

    2017-02-15

    While photons travel in a straight line at constant velocity in free space, the intensity profile of structured light may be tailored for acceleration in any degree of freedom. Here we propose a simple approach to control the angular acceleration of light. Using Laguerre-Gaussian modes as our twisted beams carrying orbital angular momentum, we show that superpositions of opposite handedness result in a radially dependent angular acceleration as they pass through a focus (waist plane). Due to conservation of orbital angular momentum, we find that propagation dynamics are complex despite the free-space medium: the outer part of the beam (rings) rotates in an opposite direction to the inner part (petals), and while the outer part accelerates, the inner part decelerates. We outline the concepts theoretically and confirm them experimentally. Such exotic structured light beams are topical due to their many applications, for instance in optical trapping and tweezing, metrology, and fundamental studies in optics.

  17. Radial vibrations of BPS skyrmions

    NASA Astrophysics Data System (ADS)

    Adam, C.; Haberichter, M.; Romanczukiewicz, T.; Wereszczynski, A.

    2016-11-01

    We study radial vibrations of spherically symmetric Skyrmions in the Bogomol'nyi-Prasad-Sommerfield Skyrme model. Concretely, we numerically solve the linearized field equations for small fluctuations in a Skyrmion background, both for linearly stable oscillations and for (unstable) resonances. This is complemented by numerical solutions of the full nonlinear system, which confirm all the results of the linear analysis. In all cases, the resulting fundamental excitation provides a rather accurate value for the Roper resonance, supporting the hypothesis that the Bogomol'nyi-Prasad-Sommerfield Skyrme model already gives a reasonable approximate description of this resonance. Furthermore, for many potentials additional higher resonances appear, again in agreement with known experimental results.

  18. PRECISION RADIAL VELOCITIES WITH CSHELL

    SciTech Connect

    Crockett, Christopher J.; Prato, L.; Mahmud, Naved I.; Johns-Krull, Christopher M.; Jaffe, Daniel T.; Beichman, Charles A. E-mail: lprato@lowell.edu E-mail: cmj@rice.edu

    2011-07-10

    Radial velocity (RV) identification of extrasolar planets has historically been dominated by optical surveys. Interest in expanding exoplanet searches to M dwarfs and young stars, however, has motivated a push to improve the precision of near-infrared RV techniques. We present our methodology for achieving 58 m s{sup -1} precision in the K band on the M0 dwarf GJ 281 using the CSHELL spectrograph at the 3 m NASA Infrared Telescope Facility. We also demonstrate our ability to recover the known 4 M{sub JUP} exoplanet Gl 86 b and discuss the implications for success in detecting planets around 1-3 Myr old T Tauri stars.

  19. Giant left ventricular pseudoaneurysm.

    PubMed

    Prakash, Sumi; Garg, Nadish; Xie, Gong-Yuan; Dellsperger, Kevin C

    2010-01-01

    Left ventricular (LV) pseudoaneurysm (PS) is an uncommon, often fatal complication associated with myocardial infarction, cardiothoracic surgery, trauma, and, rarely, infective endocarditis. A 28-year-old man with prior history of bioprosthetic mitral valve replacement presented with congestive heart failure and bacteremia with Abiotrophia granulitica. Transesophageal echocardiogram showed bioprosthesis dysfunction, large vegetations, mitral regurgitation, and probable PS. Cardiac and chest CT confirmed a PS communicating with the left ventricle Patient had pulseless electrical activity and died. Autopsy showed a giant PS with layered thrombus and pseudo-endothelialized cavity. Our case highlights the importance of multimodality imaging as an important tool in management of PS.

  20. Radial deformation of the earth by oceanic tidal loading

    NASA Technical Reports Server (NTRS)

    Ray, R. D.; Sanchez, B. V.

    1989-01-01

    A high-degree spherical harmonic series is used to compute the radial deformation of the Earth by oceanic tidal loading. By exploiting fast numerical transforms, this approach is found to be much more efficient, but no less accurate, than the traditional Green's function approach. The method is used to derive an atlas of load tide maps for 10 constitutents of the NSWC ocean tide model.

  1. Critical Hand Ischemia After Radial Access for Coronary Angiography – Case Report

    PubMed Central

    Bojakowski, Krzysztof; Zawadzki, Michał; Mruk, Bartosz; Andziak, Piotr; Walecki, Jerzy

    2017-01-01

    Summary Background Radial artery is now the most frequent access for coronary angiography and intervention. Despite the common opinion that it is safer than femoral access, it has the potential for serious complications. One of them is upper limb ischemia caused by radial artery thrombosis. Case Report We are presenting a case of critical hand ischemia after coronary angiography performed through radial access despite existing risk factors, which may be considered as relative contraindications. Conclusions In the presented case, decision was made to use radial access despite several risk factors of upper limb ischemia – diabetes, end-stage renal failure, hyperparathyroidism, or even symptoms of left upper limb ischemia. Furthermore, for diagnostic coronary angiography 5F instead of 4F introducer was used. PMID:28144386

  2. Superficial radial neuropathy and brachioradial motor nerve palsy associated with proximal radius osteochondroma.

    PubMed

    Oz, Oğuzhan; Yücel, Mehmet; Ulaş, Umit; Eroğlu, Erdal; Odabaşi, Zeki

    2010-01-01

    The cutaneous branch of the radial nerve (superficial radial nerve, SRN) might be compressed or injured at various anatomical sites along its course in the forearm. Compression of the SRN occurring at the proximal third of the forearm is unusual. A 22-year-old man was admitted with pain and paraesthesia over the lateral aspect of his right wrist and thumb and pain at the elbow for six months. In electrodiagnostic testing, a sensory nerve action potential from the right SRN could not be recorded, while it was normal on the left. In a needle electromyography study, denervation potentials have been seen in the right brachioradial muscle and a decrease in interference pattern signals was also found. An exophytic lesion of the proximal radius was observed in radiographs. Computed tomography evaluation revealed an osteochondroma of the proximal radius. Neuropathies of the SRN and the brachioradial motor branch of the radial nerve are thought to be associated with proximal radial osteochondroma.

  3. Socket stars: UBVRJIK radial profiles

    NASA Astrophysics Data System (ADS)

    Schaefer, Bradley E.

    1995-05-01

    Visual inspectin of stars embedded in H II nebulae has shown a significant fraction to be surrounded by nearly symmetric extended regions within which the nebular brightness is apparently significantly fainter than is typical for the surrounding area. These 'socket stars' might be caused by a bubble in the nebula blown out by a stellar wind or they might be caused by a circumstellar envelope of dust hiding the emission behind the star. As such, the sockets could be the first manifestation of a previously unknown component of pre-main-sequence stars. Unfortunately, no quantitative proof of the existence of sockets has been presented. To fill this need, I have imaged 10 socket stars and six background stars with CCD cameras and infrared array cameras. From these images, I have constructed radial plots which should reveal dips in brightness immediately outside the seeing disk. The radial plots do not show any evidence for the existence of sockets. A detailed examination of the photographs orginally used to identify the sockets show that the causes of these reports are (1) artifacts resulting from the photographic process of dodging and (2) random coincidence of stars with local minima in nebular brightness. Thus, I conclude that 'socket stars' do not exist.

  4. No Baby Left behind

    ERIC Educational Resources Information Center

    Blanton, Dorothy

    2007-01-01

    "No Baby Left Behind" was created to have an impact on the school readiness of children in the community today and in the future. Each year, there are an increasing number of students who have learning difficulties. Many of these problems are preventable. Accidents, poor nutrition (of the mother and/or child), drug use, alcohol use, and lack of…

  5. No Cow Left Behind

    ERIC Educational Resources Information Center

    Remsen, Kenneth A.

    2004-01-01

    As a principal facing the task of figuring out all the complexities of the No Child Left Behind legislation, Kenneth Remsen, has concluded there is a strong belief that testing students is the answer to bringing about improvements in student performance. Because testing seems to be a cornerstone to improving performance, he doesn't understand why…

  6. Accountability Left Behind

    ERIC Educational Resources Information Center

    Testani, Rocco E.; Mayes, Joshua A.

    2008-01-01

    This article describes the reversal of the dismissal of an "unfunded-mandates" challenge to the No Child Left Behind Act (NCLB) brought by the National Education Association (NEA), several of its affiliates, and a number of school districts by the United States Court of Appeals for the Sixth Circuit. The decision in "School District…

  7. Copy-left and Copy-right

    NASA Astrophysics Data System (ADS)

    VanderPlas, Jacob

    2015-01-01

    Any discussion of open licensing almost invariably devolves into a debate between copy-left licenses and permissive licenses, both sides defending their views with a nearly religious fervor. Copy-left licenses, typified by the GPL family of licenses, require all derived products to maintain the open, GPL license. Permissive licenses, typified by the BSD family of licenses, do not impose such requirements. I'll briefly explore the common arguments put forth in favor of either approach, and discuss some concrete examples of where these approaches have helped or hindered the software packages that used them.

  8. An Exact Formula for Calculating Inverse Radial Lens Distortions

    PubMed Central

    Drap, Pierre; Lefèvre, Julien

    2016-01-01

    This article presents a new approach to calculating the inverse of radial distortions. The method presented here provides a model of reverse radial distortion, currently modeled by a polynomial expression, that proposes another polynomial expression where the new coefficients are a function of the original ones. After describing the state of the art, the proposed method is developed. It is based on a formal calculus involving a power series used to deduce a recursive formula for the new coefficients. We present several implementations of this method and describe the experiments conducted to assess the validity of the new approach. Such an approach, non-iterative, using another polynomial expression, able to be deduced from the first one, can actually be interesting in terms of performance, reuse of existing software, or bridging between different existing software tools that do not consider distortion from the same point of view. PMID:27258288

  9. Weighing Rocky Exoplanets with Improved Radial Velocimetry

    NASA Astrophysics Data System (ADS)

    Xuesong Wang, Sharon; Wright, Jason; California Planet Survey Consortium

    2016-01-01

    The synergy between Kepler and the ground-based radial velocity (RV) surveys have made numerous discoveries of small and rocky exoplanets, opening the age of Earth analogs. However, most (29/33) of the RV-detected exoplanets that are smaller than 3 Earth radii do not have their masses constrained to better than 20% - limited by the current RV precision (1-2 m/s). Our work improves the RV precision of the Keck telescope, which is responsible for most of the mass measurements for small Kepler exoplanets. We have discovered and verified, for the first time, two of the dominant terms in Keck's RV systematic error budget: modeling errors (mostly in deconvolution) and telluric contamination. These two terms contribute 1 m/s and 0.6 m/s, respectively, to the RV error budget (RMS in quadrature), and they create spurious signals at periods of one sidereal year and its harmonics with amplitudes of 0.2-1 m/s. Left untreated, these errors can mimic the signals of Earth-like or Super-Earth planets in the Habitable Zone. Removing these errors will bring better precision to ten-year worth of Keck data and better constraints on the masses and compositions of small Kepler planets. As more precise RV instruments coming online, we need advanced data analysis tools to overcome issues like these in order to detect the Earth twin (RV amplitude 8 cm/s). We are developing a new, open-source RV data analysis tool in Python, which uses Bayesian MCMC and Gaussian processes, to fully exploit the hardware improvements brought by new instruments like MINERVA and NASA's WIYN/EPDS.

  10. Radial flow pulse jet mixer

    DOEpatents

    VanOsdol, John G.

    2013-06-25

    The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

  11. Left musculus sternalis.

    PubMed

    Arráez-Aybar, L A; Sobrado-Perez, J; Merida-Velasco, J R

    2003-07-01

    During routine dissection in the Morphological Sciences Department II of the Universidad Complutense de Madrid, the presence of a sternalis muscle was observed in the left hemithorax of a 70-year-old male cadaver. We report on its position, relationships, and innervation, as well as its clinical relevance, indicating some guidelines for its physical examination. We also present a brief overview of the existing literature regarding the nomenclature, historical reports, and incidence of this muscle.

  12. Tolerancing a radial velocity spectrometer within Zemax

    NASA Astrophysics Data System (ADS)

    Gibson, Steven R.

    2016-08-01

    Techniques are described for tolerancing a radial velocity spectrometer system within Zemax, including: how to set up and verify the tolerancing model, performance metrics and tolerance operands used, as well as post- Zemax analysis methods. Use of the tolerancing model for various analyses will be discussed, such as: alignment sensitivity, radial velocity sensitivity, and sensitivity of the optical system to temperature changes. Tolerance results from the Keck Planet Finder project (a precision radial velocity spectrometer of asymmetric white pupil design) will be shown.

  13. Irreducible dislocation of the radial head with undisplaced olecranon fracture in a child: a case report.

    PubMed

    Takase, Katsumi; Mizuochi, Jun

    2011-09-01

    Irreducible isolated dislocation of the radial head is a rare injury. In this study, we describe a patient with irreducible dislocation of the radial head associated with an undisplaced fracture of the olecranon. A 6-year-old girl fell down while walking and suffered injury to the posterior aspect of the proximal ulnar shaft with the right elbow in a slightly flexed position. Plain radiographs of the elbow revealed an anterior-medial dislocation of the radial head and an undisplaced fracture of the olecranon. However, the attempted closed reduction was not successful. An open reduction was then performed through a lateral approach. The radial head was found to be protruding through a buttonhole tear of the anterior joint capsule, causing the joint to become interposed between the articular surfaces of the joint, precluding closed reduction. Once the interposed capsule was extricated from the joint, the radial head could be easily reduced. At this point, no tear of the annular ligament was observed. Six months after the surgery, the patient was able to use her elbow fully and without pain. The range of motion was 0-140° for both extension and flexion and 90° for pronation and supination. Plain radiographs revealed a united bone of the olecranon and good reduction of the radial head. The radial head pushed through the tear of the anterior joint capsule. This buttonhole effect on the radial head prevented closed reduction of the radial head.

  14. Are axial and radial flow chromatography different?

    PubMed

    Besselink, Tamara; van der Padt, Albert; Janssen, Anja E M; Boom, Remko M

    2013-01-04

    Radial flow chromatography can be a solution for scaling up a packed bed chromatographic process to larger processing volumes. In this study we compared axial and radial flow affinity chromatography both experimentally and theoretically. We used an axial flow column and a miniaturized radial flow column with a ratio of 1.8 between outer and inner surface area, both with a bed height of 5 cm. The columns were packed with affinity resin to adsorb BSA. The average velocity in the columns was set equal. No difference in performance between the two columns could be observed. To gain more insight into the design of a radial flow column, the velocity profile and resin distribution in the radial flow column were calculated. Using mathematical models we found that the breakthrough performance of radial flow chromatography is very similar to axial flow when the ratio between outer and inner radius of the radial flow column is around 2. When this ratio is increased, differences become more apparent, but remain small. However, the ratio does have a significant influence on the velocity profile inside the resin bed, which directly influences the pressure drop and potentially resin compression, especially at higher values for this ratio. The choice between axial and radial flow will be based on cost price, footprint and packing characteristics. For small-scale processes, axial flow chromatography is probably the best choice, for resin volumes of at least several tens of litres, radial flow chromatography may be preferable.

  15. Close view looking to left side of statue showing left ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Close view looking to left side of statue showing left hand, shield, and laurel wreath - U.S. Capitol, Statue of Freedom, Intersection of North, South, & East Capitol Streets & Capitol Mall, Washington, District of Columbia, DC

  16. The Expansion and Radial Speeds of Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Gopalswamy, N.; Dal Lago, A.; Yashiro, S.; Akiyama, S.

    We show the relation between radial (V_{rad}) and expansion (V_{exp}) speeds of coronal mass ejections (CMEs) depends on the CME width. As CME width increases, {V_{rad}/V_{exp}} decreases from a value >1 to <1. For widths approaching 180°, the ratio approaches 0 if the cone has a flat base, while it approaches 0.5 if the base has a bulge (ice cream cone). The speed difference between the limb and disk halos and the spherical expansion of super fast CMEs can be explained by the width dependence.

  17. Left ventricular pseudoaneurysm perceived as a left lung mass

    PubMed Central

    Yaliniz, Hafize; Gocen, Ugur; Atalay, Atakan; Salih, Orhan Kemal

    2016-01-01

    Left ventricular pseudoaneurysm is a rare complication of aneurysmectomy. We present a case of a surgically treated left ventricular pseudoaneurysm, which was diagnosed three years after coronary artery bypass grafting and left ventricular aneurysmectomy. The presenting symptoms, diagnostic evaluation, and surgical repair are described. PMID:27516793

  18. Left Atrial Appendage Closure Devices

    PubMed Central

    Romero, Jorge; Perez, Irving E; Krumerman, Andrew; Garcia, Mario J; Lucariello, Richard J

    2014-01-01

    Atrial fibrillation (AF) increases the risk for thromboembolic stroke five-fold. The left atrial appendage (LAA) has been shown to be the main source of thrombus formation in the majority of strokes associated with AF. Oral anticoagulation with warfarin and novel anticoagulants remains the standard of care; however, it has several limitations, including bleeding and poor compliance. Occlusion of the LAA has been shown to be an alternative therapeutic approach to drug therapy. The purpose of this article is to review the different techniques and devices that have emerged for the purpose of occluding this structure, with a particular emphasis on the efficacy and safety studies published to date in the medical literature. PMID:24963274

  19. Surface interpolation with radial basis functions for medical imaging

    SciTech Connect

    Carr, J.C.; Beatson, R.K.; Fright, W.R.

    1997-02-01

    Radial basis functions are presented as a practical solution to the problem of interpolating incomplete surfaces derived from three-dimensional (3-D) medical graphics. The specific application considered is the design of cranial implants for the repair of defects, usually holes, in the skull. Radial basis functions impose few restrictions on the geometry of the interpolation centers and are suited to problems where interpolation centers do not form a regular grid. However, their high computational requirements have previously limited their use to problems where the number of interpolation centers is small (<300). Recently developed fast evaluation techniques have overcome these limitations and made radial basis interpolation a practical approach for larger data sets. In this paper radial basis functions are fitted to depth-maps of the skull`s surface, obtained from X-ray computed tomography (CT) data using ray-tracing techniques. They are used to smoothly interpolate the surface of the skull across defect regions. The resulting mathematical description of the skull`s surface can be evaluated at any desired resolution to be rendered on a graphics workstation or to generate instructions for operating a computer numerically controlled (CNC) mill.

  20. Differentiating common causes of radial wrist pain.

    PubMed

    Shuaib, Waqas; Mohiuddin, Zia; Swain, Freddie R; Khosa, Faisal

    2014-09-01

    Radial wrist pain is a common patient complaint with a broad differential. Because treatment and prognosis differ, determining the underlying cause is key. This article reviews a case of intersection syndrome and compares it to other causes of radial wrist pain.

  1. Radial Correlations Between Two Quarks

    NASA Astrophysics Data System (ADS)

    Green, A. M.; Koponen, J.; Pennanen, P.; Michael, C.

    2002-04-01

    In nuclear many-body problems the short-range correlation between two nucleons is well described by the corresponding correlation in the two-body problem. Therefore, as a first step in any attempt at an analogous description of many-quark systems, it is necessary to know the two-quark correlation. With this in mind, we study the light quark distribution in a heavy-light meson with a static heavy quark. The charge and matter radial distributions of these heavy-light mesons are measured on a lattice with a light quark mass about that of the strange quark. Both distributions can be well fitted upto r ≈ 0.7 fm with the exponential form wi2 (r), where Wi(r) = A exp(-r/ri). For the charge(c) and matter(m) distributions rc ≈ 0.32(2)fm and rm ≈ 0.24(2)fm. We also discuss the normalisation of the total charge (defined to be unity in the continuum limit) and matter integrated over all space, finding 1.30(5) and 0.4(1) respectively for a lattice spacing ≈ 0.17 fm.

  2. Combination radial and thrust magnetic bearing

    NASA Technical Reports Server (NTRS)

    Blumenstock, Kenneth A. (Inventor)

    2002-01-01

    A combination radial and thrust magnetic bearing is disclosed that allows for both radial and thrust axes control of an associated shaft. The combination radial and thrust magnetic bearing comprises a rotor and a stator. The rotor comprises a shaft, and first and second rotor pairs each having respective rotor elements. The stator comprises first and second stator elements and a magnet-sensor disk. In one embodiment, each stator element has a plurality of split-poles and a corresponding plurality of radial force coils and, in another embodiment, each stator element does not require thrust force coils, and radial force coils are replaced by double the plurality of coils serving as an outer member of each split-pole half.

  3. Segmental Analysis of Cardiac Short-Axis Views Using Lagrangian Radial and Circumferential Strain.

    PubMed

    Ma, Chi; Wang, Xiao; Varghese, Tomy

    2016-11-01

    Accurate description of myocardial deformation in the left ventricle is a three-dimensional problem, requiring three normal strain components along its natural axis, that is, longitudinal, radial, and circumferential strains. Although longitudinal strains are best estimated from long-axis views, radial and circumferential strains are best depicted in short-axis views. An algorithm that utilizes a polar grid for short-axis views previously developed in our laboratory for a Lagrangian description of tissue deformation is utilized for radial and circumferential displacement and strain estimation. Deformation of the myocardial wall, utilizing numerical simulations with ANSYS, and a finite-element analysis-based canine heart model were adapted as the input to a frequency-domain ultrasound simulation program to generate radiofrequency echo signals. Clinical in vivo data were also acquired from a healthy volunteer. Local displacements estimated along and perpendicular to the ultrasound beam propagation direction are then transformed into radial and circumferential displacements and strains using the polar grid based on a pre-determined centroid location. Lagrangian strain variations demonstrate good agreement with the ideal strain when compared with Eulerian results. Lagrangian radial and circumferential strain estimation results are also demonstrated for experimental data on a healthy volunteer. Lagrangian radial and circumferential strain tracking provide accurate results with the assistance of the polar grid, as demonstrated using both numerical simulations and in vivo study.

  4. Enhanced radial transport and energization of radiation belt electrons due to drift orbit bifurcations.

    PubMed

    Ukhorskiy, A Y; Sitnov, M I; Millan, R M; Kress, B T; Smith, D C

    2014-01-01

    [1]Relativistic electron intensities in Earth's outer radiation belt can vary by multiple orders of magnitude on the time scales ranging from minutes to days. One fundamental process contributing to dynamic variability of radiation belt intensities is the radial transport of relativistic electrons across their drift shells. In this paper we analyze the properties of three-dimensional radial transport in a global magnetic field model driven by variations in the solar wind dynamic pressure. We use a test particle approach which captures anomalous effects such as drift orbit bifurcations. We show that the bifurcations lead to an order of magnitude increase in radial transport rates and enhance the energization at large equatorial pitch angles. Even at quiet time fluctuations in dynamic pressure, radial transport at large pitch angles exhibits strong deviations from the diffusion approximation. The radial transport rates are much lower at small pitch angle values which results in a better agreement with the diffusion approximation.

  5. The radial plasma structure of 1E 0102.2-7219

    NASA Astrophysics Data System (ADS)

    Flanagan, K. A.; Canizares, C. R.; Houck, J. C.; Fredericks, A. C.

    Chandra High Energy Transmission Grating Spectrometer observations of 1E 0102 2-7219 have revealed marked radial dependence in its ionization structure Flanagan it et al 2004 In order to explore intrinsic radial variations of temperature or other plasma parameters line ratios may provide useful diagnostics if projection effects are taken into account We have approached this problem using a spatial model of the emission including orientation angular and radial distribution We use MARX to simulate observations of a 3D SNR emissivity distribution and compare these simulations with the actual X-ray line image to fit radial distributions of key diagnostic lines Plasma parameters are derived by forming ratios from the best-fit radial models for each X-ray line We find that ionization age and electron temperature increase smoothly with radius We examine the implications with regard to electron density shock velocity and electron-ion equilibration

  6. New constraints on Earth's radial conductivity structure

    NASA Astrophysics Data System (ADS)

    Püthe, Christoph; Kuvshinov, Alexey; Olsen, Nils; Sabaka, Terence

    2014-05-01

    We present a new model of Earth's radial (1-D) conductivity structure at depths between 10 km and the core-mantle boundary. It is based on CM5, the latest version in the Comprehensive Model series that has been derived using 13 years (September 2000 to September 2013) of magnetic data collected by the three satellites Oersted, CHAMP and SAC-C and at the global network of geomagnetic observatories. CM5 describes contributions due to sources in core, lithosphere, ionosphere and magnetosphere (and corresponding induced parts) in form of spherical harmonic expansion (SHE) coefficients. Removing predictions of the core, lithospheric and ionospheric field contributions as given by CM5 from the observations, we determine time series of the dominating external and induced SHE coefficients of the magnetic potential due to the magnetospheric ring current. Scalar Q-responses are estimated from these coefficients. An iterative approach is used to correct the estimated responses for 3-D effects arising from lateral heterogeneities in the top 10 km. The corrected Q-responses are converted to C-responses; the latter are subsequently inverted for the layered 1-D mantle conductivity profile with the Newton method. The Hessian matrix of the misfit function, which is derived analytically, is used to estimate confidence limits for the conductivity of each layer. The resulting conductivity-depth profile is compared to 1-D conductivity models of Earth's mantle recovered in previous studies.

  7. Left ventricular apical diseases.

    PubMed

    Cisneros, Silvia; Duarte, Ricardo; Fernandez-Perez, Gabriel C; Castellon, Daniel; Calatayud, Julia; Lecumberri, Iñigo; Larrazabal, Eneritz; Ruiz, Berta Irene

    2011-08-01

    There are many disorders that may involve the left ventricular (LV) apex; however, they are sometimes difficult to differentiate. In this setting cardiac imaging methods can provide the clue to obtaining the diagnosis. The purpose of this review is to illustrate the spectrum of diseases that most frequently affect the apex of the LV including Tako-Tsubo cardiomyopathy, LV aneurysms and pseudoaneurysms, apical diverticula, apical ventricular remodelling, apical hypertrophic cardiomyopathy, LV non-compaction, arrhythmogenic right ventricular dysplasia with LV involvement and LV false tendons, with an emphasis on the diagnostic criteria and imaging features. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13244-011-0091-6) contains supplementary material, which is available to authorized users.

  8. Radial Head and Neck Allograft for Comminute Irreparable Fracture-Dislocations of the Elbow.

    PubMed

    Bisicchia, Salvatore; Tudisco, Cosimo

    2016-11-01

    Fracture-dislocations of the elbow can be difficult to treat, with unsatisfactory results in some cases. In general, it is preferable to preserve the fractured radial head when possible, but some patients present a unique treatment challenge because of extremely comminuted fractures and bone loss. In these cases, the only options available are radial head prosthesis or allograft. The authors present a case of a 45-year-old man with a fracture-dislocation of the left elbow that was treated with an allograft of the radial head and neck because of extreme comminution of the fracture. There have been a few reports about osteochondral allograft transplantation of the radial head, and they all included traumatic or posttraumatic cases treated with a frozen allograft. To the best of the authors' knowledge, this is the first report on the use of osteochondral allograft in the acute setting for the treatment of a comminuted fracture of the radius involving the whole head and neck. The clinical results were satisfactory at the final follow-up, although mild degenerative changes were present, the screws were coming loose, and the radial head had a slight valgus deformity. Radial head allograft can be an option in selected cases of acute fractures with severe comminution and bone loss that are not amenable to a stable internal fixation; for the young and active patient, who is not the best candidate for radial head resection; or in cases in which radial head arthroplasty is not feasible because of severe bone loss. [Orthopedics. 2016; 39(6):e1205-e1208.].

  9. Impaired Verbal Associative Learning after Resection of Left Perirhinal Cortex

    ERIC Educational Resources Information Center

    Weintrob, David L.; Saling, Michael M.; Berkovic, Samuel F.; Reutens, David C.

    2007-01-01

    Some patients considered for left temporal lobectomy for epilepsy present with normal verbal learning and no MRI evidence of hippocampal pathology. In order to preserve learning function, the surgical approach in these cases often aims at sparing the hippocampus. Parahippocampal structures, including the left perirhinal region, however, also…

  10. Ion radial transport induced by ICRF waves in tokamaks

    SciTech Connect

    Chen, L.; Vaclavik, J.; Hammett, G.W.

    1987-05-01

    The wave-induced fluxes of energetic-trapped ions during ICRF heating of tokamak plasmas are calculated using quasilinear equations. A simple single particle model of this transport mechanism is also given. Both a convective flux proportional to k/sub phi/vertical bar E/sub +/vertical bar/sup 2/ and a diffusive flux proportional to k/sub phi//sup 2/vertical bar E/sub +/vertical bar/sup 2/ are found. Here, k/sub phi/ is the toroidal wave number and E/sub +/ is the left-hand polarized wave field. The convective flux may become significant for large k/sub phi/ if the wave spectrum is asymmetric in k/sub phi/. But for the conditions of most previous experiments, these calculations indicate that radial transport driven directly by the ICRF wave is unimportant.

  11. Left Atrial Appendage Exclusion for Atrial Fibrillation

    PubMed Central

    Syed, Faisal F.; DeSimone, Christopher V.; Friedman, Paul A.; Asirvatham, Samuel J.

    2015-01-01

    SYNOPSIS Percutaneous left atrial appendage (LAA) closure is increasingly being used as a treatment strategy to prevent stroke in patients with atrial fibrillation (AF) who have contraindications to anticoagulants. A number of approaches and devices have been developed in the last few years, each with their own unique set of advantages and disadvantages. We review the published studies on surgical and percutaneous approaches to LAA closure; focusing on stroke mechanisms in AF, LAA structure and function relevant to stroke prevention, practical differences in procedural approach, and clinical considerations surrounding management. PMID:25443240

  12. [Left-handedness and health].

    PubMed

    Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

    2010-01-01

    Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome), developmental disorders (autism, dislexia and sttutering) and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about "anomalous" cerebral domination, as a consequence of hormonal disbalance.

  13. Study on the radial composite piezoelectric ceramic transducer in radial vibration.

    PubMed

    Lin, Shuyu

    2007-03-01

    A new type of radial composite piezoelectric transducer in radial vibration is developed and analyzed. The radial composite transducer consists of a piezoelectric ceramic thin ring polarized in the thickness direction and a metal thin circular ring. They are connected together and excited to vibrate in the radial direction. The radial vibrations of a piezoelectric ceramic thin ring and a metal thin circular ring are analyzed, respectively. Their radial electro-mechanical equivalent circuits are obtained. Based on the electro-mechanical equivalent circuits and using the boundary conditions between the piezoelectric ceramic thin ring and the metal thin circular ring in the radial direction, the electro-mechanical equivalent circuit of the radial composite piezoelectric transducer is derived out and the resonance frequency equation is obtained. The relationship between the resonance frequency and the geometrical dimensions of the transducer is analyzed. Some radial composite piezoelectric transducers are designed and manufactured. The resonance frequencies and the anti-resonance frequencies, the electro-mechanical equivalent circuit parameters are measured. The effective electro-mechanical coupling coefficient and the mechanical quality factor are calculated. It is illustrated that the measured radial resonance frequencies are in good agreement with the theoretical results from the resonance frequency equation.

  14. Radial velocity data analysis with compressed sensing techniques

    NASA Astrophysics Data System (ADS)

    Hara, Nathan C.; Boué, G.; Laskar, J.; Correia, A. C. M.

    2017-01-01

    We present a novel approach for analysing radial velocity data that combines two features: all the planets are searched at once and the algorithm is fast. This is achieved by utilizing compressed sensing techniques, which are modified to be compatible with the Gaussian process framework. The resulting tool can be used like a Lomb-Scargle periodogram and has the same aspect but with much fewer peaks due to aliasing. The method is applied to five systems with published radial velocity data sets: HD 69830, HD 10180, 55 Cnc, GJ 876 and a simulated very active star. The results are fully compatible with previous analysis, though obtained more straightforwardly. We further show that 55 Cnc e and f could have been respectively detected and suspected in early measurements from the Lick Observatory and Hobby-Eberly Telescope available in 2004, and that frequencies due to dynamical interactions in GJ 876 can be seen.

  15. Radial displacement sensor for non-contact bearings

    NASA Technical Reports Server (NTRS)

    McCormick, John A. (Inventor); Sixsmith, Herbert (Inventor)

    1998-01-01

    A radial position sensor includes four capacitive electrodes oriented about a shaft, arranged in two diametrically opposite pairs. Sensor circuitry generates an output signal in proportion to the capacitance between the electrodes and the shaft; the capacitance between an electrode and the shaft increases as the shaft approaches the electrode and decreases as the shaft recedes from the electrode. The sensor circuitry applies an alternating voltage to one electrode of a pair and a 180 degree out of phase alternating voltage to the other electrode of the pair. The electrical responses of the two electrodes to their respective input signals are summed to form a radial deviation signal which is relatively free from the alternating voltage and accurately represents the position of the shaft relative to the electrodes of the pair.

  16. Radial polar histogram: obstacle avoidance and path planning for robotic cognition and motion control

    NASA Astrophysics Data System (ADS)

    Wang, Po-Jen; Keyawa, Nicholas R.; Euler, Craig

    2012-01-01

    In order to achieve highly accurate motion control and path planning for a mobile robot, an obstacle avoidance algorithm that provided a desired instantaneous turning radius and velocity was generated. This type of obstacle avoidance algorithm, which has been implemented in California State University Northridge's Intelligent Ground Vehicle (IGV), is known as Radial Polar Histogram (RPH). The RPH algorithm utilizes raw data in the form of a polar histogram that is read from a Laser Range Finder (LRF) and a camera. A desired open block is determined from the raw data utilizing a navigational heading and an elliptical approximation. The left and right most radii are determined from the calculated edges of the open block and provide the range of possible radial paths the IGV can travel through. In addition, the calculated obstacle edge positions allow the IGV to recognize complex obstacle arrangements and to slow down accordingly. A radial path optimization function calculates the best radial path between the left and right most radii and is sent to motion control for speed determination. Overall, the RPH algorithm allows the IGV to autonomously travel at average speeds of 3mph while avoiding all obstacles, with a processing time of approximately 10ms.

  17. Radial gate evaluation: Olympus Dam, Colorado

    SciTech Connect

    1997-06-01

    The report presents a structural analysis of the radial gates of Olympus Dam in eastern Colorado. Five 20-foot wide by 17-foot high radial gates are used to control flow through the spillway at Olympus Dam. The spillway gates were designed in 1947. The gate arm assemblies consist of two separate wide flange beams, with a single brace between the arms. The arms pivot about a 4.0-inch diameter pin and bronze graphite-insert bushing. The pin is cantilevered from the pier anchor girder. The radial gates are supported by a pin bearing on a pier anchor birder bolted to the end of the concrete pier. The gates are operated by two-part wire rope 15,000-pound capacity hoise. Stoplog slots upstream of the radial gates are provided in the concrete piers. Selected drawings of the gates and hoists are located in appendix A.

  18. Radial construction of an arterial wall.

    PubMed

    Greif, Daniel M; Kumar, Maya; Lighthouse, Janet K; Hum, Justine; An, Andrew; Ding, Ling; Red-Horse, Kristy; Espinoza, F Hernan; Olson, Lorin; Offermanns, Stefan; Krasnow, Mark A

    2012-09-11

    Some of the most serious diseases involve altered size and structure of the arterial wall. Elucidating how arterial walls are built could aid understanding of these diseases, but little is known about how concentric layers of muscle cells and the outer adventitial layer are assembled and patterned around endothelial tubes. Using histochemical, clonal, and genetic analysis in mice, here we show that the pulmonary artery wall is constructed radially, from the inside out, by two separate but coordinated processes. One is sequential induction of successive cell layers from surrounding mesenchyme. The other is controlled invasion of outer layers by inner layer cells through developmentally regulated cell reorientation and radial migration. We propose that a radial signal gradient controls these processes and provide evidence that PDGF-B and at least one other signal contribute. Modulation of such radial signaling pathways may underlie vessel-specific differences and pathological changes in arterial wall size and structure.

  19. The fundamental definition of ``radial velocity''

    NASA Astrophysics Data System (ADS)

    Lindegren, Lennart; Dravins, Dainis

    2003-04-01

    Accuracy levels of metres per second require the fundamental concept of ``radial velocity'' for stars and other distant objects to be examined, both as a physical velocity, and as measured by spectroscopic and astrometric techniques. Already in a classical (non-relativistic) framework the line-of-sight velocity component is an ambiguous concept, depending on whether, e.g., the time of light emission (at the object) or that of light detection (by the observer) is used for recording the time coordinate. Relativistic velocity effects and spectroscopic measurements made inside gravitational fields add further complications, causing wavelength shifts to depend, e.g., on the transverse velocity of the object and the gravitational potential at the source. Aiming at definitions that are unambiguous at accuracy levels of 1 m s-1, we analyse different concepts of radial velocity and their interrelations. At this accuracy level, a strict separation must be made between the purely geometric concepts on one hand, and the spectroscopic measurement on the other. Among the geometric concepts we define kinematic radial velocity, which corresponds most closely to the ``textbook definition'' of radial velocity as the line-of-sight component of space velocity; and astrometric radial velocity, which can be derived from astrometric observations. Consistent with these definitions, we propose strict definitions also of the complementary kinematic and astrometric quantities, namely transverse velocity and proper motion. The kinematic and astrometric radial velocities depend on the chosen spacetime metric, and are accurately related by simple coordinate transformations. On the other hand, the observational quantity that should result from accurate spectroscopic measurements is the barycentric radial-velocity measure. This is independent of the metric, and to first order equals the line-of-sight velocity. However, it is not a physical velocity, and cannot be accurately transformed to a

  20. Radial averages of astigmatic TEM images.

    PubMed

    Fernando, K Vince

    2008-10-01

    The Contrast Transfer Function (CTF) of an image, which modulates images taken from a Transmission Electron Microscope (TEM), is usually determined from the radial average of the power spectrum of the image (Frank, J., Three-dimensional Electron Microscopy of Macromolecular Assemblies, Oxford University Press, Oxford, 2006). The CTF is primarily defined by the defocus. If the defocus estimate is accurate enough then it is possible to demodulate the image, which is popularly known as the CTF correction. However, it is known that the radial average is somewhat attenuated if the image is astigmatic (see Fernando, K.V., Fuller, S.D., 2007. Determination of astigmatism in TEM images. Journal of Structural Biology 157, 189-200) but this distortion due to astigmatism has not been fully studied or understood up to now. We have discovered the exact mathematical relationship between the radial averages of TEM images with and without astigmatism. This relationship is determined by a zeroth order Bessel function of the first kind and hence we can exactly quantify this distortion in the radial averages of signal and power spectra of astigmatic images. The argument to this Bessel function is similar to an aberration function (without the spherical aberration term) except that the defocus parameter is replaced by the differences of the defoci in the major and minor axes of astigmatism. The ill effects due this Bessel function are twofold. Since the zeroth order Bessel function is a decaying oscillatory function, it introduces additional zeros to the radial average and it also attenuates the CTF signal in the radial averages. Using our analysis, it is possible to simulate the effects of astigmatism in radial averages by imposing Bessel functions on idealized radial averages of images which are not astigmatic. We validate our theory using astigmatic TEM images.

  1. Radial transport with perturbed magnetic field

    SciTech Connect

    Hazeltine, R. D.

    2015-05-15

    It is pointed out that the viscosity coefficient describing radial transport of toroidal angular momentum is proportional to the second power of the gyro-radius—like the corresponding coefficients for particle and heat transport—regardless of any geometrical symmetry. The observation is widely appreciated, but worth emphasizing because some literature gives the misleading impression that asymmetry can allow radial moment transport in first-order.

  2. Osteopathic treatment in a patient with left-ventricular assist device with left brachialgia: a case report

    PubMed Central

    Bordoni, Bruno; Marelli, Fabiola; Morabito, Bruno; Sacconi, Beatrice

    2017-01-01

    This study deals with an osteopathic approach used for a patient with left-ventricular assist device (L-VAD) affected by left brachialgia. Clinical examination revealed the presence of thoracic outlet syndrome and pectoralis minor syndrome, with compression of the left proximal ulnar nerve, related to the surgical sternotomy performed. The osteopathic techniques used can be classified as indirect and direct, addressed to the pectoralis minor and the first left rib, respectively. To our knowledge, this is the first text in literature with an osteopathic treatment in a patient with L-VAD. PMID:28144166

  3. Radial glia and somal translocation of radial neurons in the developing cerebral cortex.

    PubMed

    Nadarajah, Bagirathy

    2003-07-01

    A series of recent studies have demonstrated that radial glia are neural precursors in the developing cerebral cortex. These studies have further implied that these cells are the sole precursor constituents of the dorsal forebrain ventricular zone that generate the projection neurons of the cortex. In view of these new findings, this review discusses radial neurons, a progeny of cortical neurons that are generated by radial glia and adopt somal translocation as the mode of migration.

  4. 1. Postandbeam garage (far left), oneroom log cabin (left of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Post-and-beam garage (far left), one-room log cabin (left of center), house (right of center), garden shed and outhouse (far right). View to west-southwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

  5. 6. Livestock barn (far left), log drafthorse barn (left of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Livestock barn (far left), log draft-horse barn (left of center), loafing shed (center), log calving barn (right of center). View to west-northwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

  6. 3. Log bunkhouse (far left), log chicken house (left of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Log bunkhouse (far left), log chicken house (left of center), equipment shed (center), and workshop (far right). View to northwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

  7. [Open posterior dislocation of the elbow with fractures of the radial head and coronoid process and multiple diaphyseal fractures of the ulna].

    PubMed

    Visna, P; Kalvach, J; Beitl, E; Pilný, J; Cizmár, I

    2008-03-01

    A healthy, right-handed 34-year-old man was injured by repeated direct blows delivered to his left upper arm with a baseball bat. These blows led to a posterior dislocation of the elbow joint, associated with fractures of the radial head and the coronoid process. There was bone loss on the fractured joint surface of the olecranon, with simultaneous ipsilateral trauma to the ulna. The correct surgical approach in the case of such fractures is still the subject of some controversy. The treatment can have serious complications. The results of treatment are often poor, especially because of persisting instability and stiffness of the elbow following a long period of immobilisation. Few studies have been concentrated on this topic up to now. We report on the functional and radiological results 24 months after the treatment of this rare, open "shock triad in the elbow."

  8. [Elbow dislocation with ipsilateral proximal radial shaft fracture and radial head dislocation].

    PubMed

    Köhn, N; Mendel, T; Ullrich, B W

    2015-11-01

    Elbow dislocation with ipsilateral proximal radial shaft fracture and dislocated radial head is a rarely described injury. In this article we present the case of a 23-year-old man with this injury. After the initial diagnostics, the radial shaft fracture was osteosynthetically fixed, whereby the anatomical positions of all parts of the elbow joint were correctly aligned and the medial collateral ligament was reconstructed. After 4.5 months the radial shaft fracture was healed with nearly complete functional recovery of the upper extremity. Thus, a good outcome can be expected when all aspects of bony and ligamentous injuries are accurately addressed.

  9. Radial transport in the Earth's radiation belts (Invited)

    NASA Astrophysics Data System (ADS)

    Kress, B. T.; Ukhorskiy, A. Y.; Hudson, M. K.

    2010-12-01

    For over forty years the standard approach to modeling the dynamics of the Earth's radiation belts has been based on a diffusion equation, which can be derived from the Vlasov equation using a quasilinear approximation. The radiation belt diffusion equation describes the evolution of a particle distribution function in a space of one or several of the three adiabatic invariants associated with the motions of a charged particle in a dipole magnetic field. Increasingly, observations and theoretical studies suggest that fully nonlinear transport, not modeled by quasilinear diffusion, plays an important role in radiation belt dynamics, e.g., the shock-drift mechanism modeled by Li et al. [1993]. This presentation will focus on radiation belt particle transport across magnetic L-shells (loosely called radial transport). Radial transport is thought to be one of the primary drivers of radiation belt dynamics. A comprehensive review of the known mechanisms of radial transport and some of their effects will be given, including those that can be modeled with a diffusion equation and those requiring a fully nonlinear treatment. Li, X., I. Roth, M. Temerin, J. R. Wygant, M. K. Hudson, and J. B. Blake, (1993), Simulations of the prompt energization and transport of radiation belt particles during the March 24, 1991 SSC, Geophys. Res. Lett., 20, 2423.

  10. Laparoscopic versus open left lateral segmentectomy

    PubMed Central

    Carswell, Kirstin A; Sagias, Filippos G; Murgatroyd, Beth; Rela, Mohamed; Heaton, Nigel; Patel, Ameet G

    2009-01-01

    Background Laparoscopic liver surgery is becoming increasingly common. This cohort study was designed to directly compare perioperative outcomes of the left lateral segmentectomy via laparoscopic and open approach. Methods Between 2002 and 2006 43 left lateral segmentectomies were performed at King's College Hospital. Those excluded from analysis included previous liver resections, polycystic liver disease, liver cirrhosis and synchronous operations. Of 20 patients analysed, laparoscopic (n = 10) were compared with open left lateral segmentectomy (n = 10). Both groups had similar patient characteristics. Results Morbidity rates were similar with no wound or chest infection in either group. The conversion rate was 10% (1/10). There was no difference in operating time between the groups (median time 220 minutes versus 179 minutes, p = 0.315). Surgical margins for all lesions were clear. Less postoperative opiate analgesics were required in the laparoscopic group (median 2 days versus 5 days, p = 0.005). The median postoperative in-hospital stay was less in the laparoscopic group (6 days vs 9 days, p = 0.005). There was no mortality. Conclusion Laparoscopic left lateral segmentectomy is safe and feasible. Laparoscopic patients may benefit from requiring less postoperative opiate analgesia and a shorter post-operative in-hospital stay. PMID:19735573

  11. Left ventricular assist device outflow graft: alternative sites.

    PubMed

    El-Sayed Ahmed, Magdy M; Aftab, Muhammad; Singh, Steve K; Mallidi, Hari R; Frazier, Oscar H

    2014-09-01

    We describe three alternative approaches for the left ventricular assist device (LVAD) outflow graft during implantation of the LVAD. The supraceliac abdominal aorta, innominate artery and left axillary artery were employed as alternative sites for the LVAD outflow graft in the setting of a heavily calcified ascending aorta or a hostile chest wall and mediastinum. The first approach involved the use of the supraceliac abdominal aorta. Given that the patient had a history of multiple previous breast surgeries and chest wall radiation for breast cancer treatment, a left subcostal incision was employed as a sternotomy-sparing approach. The second approach was the use of the innominate artery in a patient with a porcelain ascending aorta. The patient underwent pulmonary valve replacement, right ventricle outflow tract reconstruction and tricuspid valve annuloplasty in addition to the LVAD implantation. The third approach was the use of the left axillary artery. This patient had a history of LVAD implantation and subsequently developed infection with pseudoaneurysm formation at the aortic anastomosis of the outflow graft. We conclude that the supraceliac abdominal aorta, the innominate artery and the left axillary artery are potential alternative routes for the LVAD outflow graft in the settings of heavily calcified ascending aorta or a hostile chest wall and mediastinum. Although the described alternative approaches are safe and viable options, we highly recommend utilizing these approaches only in selected patients with significantly higher risks and hazards to the standard surgical approach.

  12. Radial velocity studies of cool stars.

    PubMed

    Jones, Hugh R A; Barnes, John; Tuomi, Mikko; Jenkins, James S; Anglada-Escude, Guillem

    2014-04-28

    Our current view of exoplanets is one derived primarily from solar-like stars with a strong focus on understanding our Solar System. Our knowledge about the properties of exoplanets around the dominant stellar population by number, the so-called low-mass stars or M dwarfs, is much more cursory. Based on radial velocity discoveries, we find that the semi-major axis distribution of M dwarf planets appears to be broadly similar to those around more massive stars and thus formation and migration processes might be similar to heavier stars. However, we find that the mass of M dwarf planets is relatively much lower than the expected mass dependency based on stellar mass and thus infer that planet formation efficiency around low-mass stars is relatively impaired. We consider techniques to overcome the practical issue of obtaining good quality radial velocity data for M dwarfs despite their faintness and sustained activity and emphasize (i) the wavelength sensitivity of radial velocity signals, (ii) the combination of radial velocity data from different experiments for robust detection of small amplitude signals, and (iii) the selection of targets and radial velocity interpretation of late-type M dwarfs should consider Hα behaviour.

  13. Radial spoke proteins of Chlamydomonas flagella

    PubMed Central

    Yang, Pinfen; Diener, Dennis R.; Yang, Chun; Kohno, Takahiro; Pazour, Gregory J.; Dienes, Jennifer M.; Agrin, Nathan S.; King, Stephen M.; Sale, Winfield S.; Kamiya, Ritsu; Rosenbaum, Joel L.; Witman, George B.

    2007-01-01

    Summary The radial spoke is a ubiquitous component of ‘9+2’ cilia and flagella, and plays an essential role in the control of dynein arm activity by relaying signals from the central pair of microtubules to the arms. The Chlamydomonas reinhardtii radial spoke contains at least 23 proteins, only 8 of which have been characterized at the molecular level. Here, we use mass spectrometry to identify 10 additional radial spoke proteins. Many of the newly identified proteins in the spoke stalk are predicted to contain domains associated with signal transduction, including Ca2+-, AKAP- and nucleotide-binding domains. This suggests that the spoke stalk is both a scaffold for signaling molecules and itself a transducer of signals. Moreover, in addition to the recently described HSP40 family member, a second spoke stalk protein is predicted to be a molecular chaperone, implying that there is a sophisticated mechanism for the assembly of this large complex. Among the 18 spoke proteins identified to date, at least 12 have apparent homologs in humans, indicating that the radial spoke has been conserved throughout evolution. The human genes encoding these proteins are candidates for causing primary ciliary dyskinesia, a severe inherited disease involving missing or defective axonemal structures, including the radial spokes. PMID:16507594

  14. Left ventricular wall stress compendium.

    PubMed

    Zhong, L; Ghista, D N; Tan, R S

    2012-01-01

    Left ventricular (LV) wall stress has intrigued scientists and cardiologists since the time of Lame and Laplace in 1800s. The left ventricle is an intriguing organ structure, whose intrinsic design enables it to fill and contract. The development of wall stress is intriguing to cardiologists and biomedical engineers. The role of left ventricle wall stress in cardiac perfusion and pumping as well as in cardiac pathophysiology is a relatively unexplored phenomenon. But even for us to assess this role, we first need accurate determination of in vivo wall stress. However, at this point, 150 years after Lame estimated left ventricle wall stress using the elasticity theory, we are still in the exploratory stage of (i) developing left ventricle models that properly represent left ventricle anatomy and physiology and (ii) obtaining data on left ventricle dynamics. In this paper, we are responding to the need for a comprehensive survey of left ventricle wall stress models, their mechanics, stress computation and results. We have provided herein a compendium of major type of wall stress models: thin-wall models based on the Laplace law, thick-wall shell models, elasticity theory model, thick-wall large deformation models and finite element models. We have compared the mean stress values of these models as well as the variation of stress across the wall. All of the thin-wall and thick-wall shell models are based on idealised ellipsoidal and spherical geometries. However, the elasticity model's shape can vary through the cycle, to simulate the more ellipsoidal shape of the left ventricle in the systolic phase. The finite element models have more representative geometries, but are generally based on animal data, which limits their medical relevance. This paper can enable readers to obtain a comprehensive perspective of left ventricle wall stress models, of how to employ them to determine wall stresses, and be cognizant of the assumptions involved in the use of specific models.

  15. Direct Measurement of Left Atrial Pressure during Routine Transradial Catheterization

    PubMed Central

    Fa'ak, Faisal; Younis, George

    2016-01-01

    Left atrial pressure indicates the left ventricular filling pressure in patients who have systolic or diastolic left ventricular dysfunction or valvular heart disease. The use of indirect surrogate methods to determine left atrial pressure has been essential in the modern evaluation and treatment of cardiovascular disease because of the difficulty and inherent risks associated with direct methods (typically the transseptal approach). One method that has been widely used to determine left atrial pressure indirectly is Swan-Ganz catheterization, in which a balloon-flotation technique is applied to measure pulmonary capillary wedge pressure; however, this approach has been associated with several limitations and potential risks. Measuring left ventricular end-diastolic pressure has also been widely used as a simple means to estimate filling pressures but remains a surrogate for the gold standard of directly measuring left atrial pressure. We describe a simple, low-risk method to directly measure left atrial pressure that involves the use of standard coronary catheterization techniques during a transradial procedure. PMID:28100968

  16. Annular Ligament Reconstruction With Triceps Autograft for Chronic Radial Head Instability.

    PubMed

    Marinello, Patrick G; Wagner, Timothy; Styron, Joseph; Maschke, Steven; Evans, Peter J

    2016-03-01

    We present a modification and revisit of the Bell Tawse technique for annular ligament reconstruction with triceps autograft for chronic radial head instability. In patients with instability stemming from an incompetent annular ligament, this technique has proved successful to restore stability to the proximal radial capitellar joint as an augment after ensuring normal boney anatomy. Through a lateral Kocher approach, an approximately 10 cm × 4 mm strip of lateral triceps tendon is harvested as a free graft for the reconstruction. Following passing of the triceps autograft around the radial neck, it is sutured to a mini-Mitek suture anchor and is placed into a decorticated portion of the proximal ulna to recreate the annular ligament. Finally, we present 2 case illustrations where this technique was successfully used for chronic radial head instability.

  17. Radial head fracture associated with posterior interosseous nerve injury.

    PubMed

    Terra, Bernardo Barcellos; Sassine, Tannus Jorge; Lima, Guilherme de Freitas; Rodrigues, Leandro Marano; Padua, David Victoria Hoffmann; Nadai, Anderson de

    2016-01-01

    Fractures of the radial head and radial neck correspond to 1.7-5.4% of all fractures and approximately 30% may present associated injuries. In the literature, there are few reports of radial head fracture with posterior interosseous nerve injury. This study aimed to report a case of radial head fracture associated with posterior interosseous nerve injury.

  18. Off-axis radial properties of undulator light

    NASA Astrophysics Data System (ADS)

    Tatchyn, Roman; Lindau, Ingolf

    The spatial and polarization properties of light from a transverse sinusoidal undulator are investigated analytically by means of numerical simulations for the single-electron case. The terminology used in the analysis is introduced; formulations for the off-axis intensity patterns, the rest-frame analysis, and radial harmonic maxima are derived; and numerical results are presented in extensive tables and graphs and briefly characterized. It is suggested that the present approach can be extended to treat higher rings and harmonics, coherent interaction among electrons (as in beam bunching and FELs), and random imperfections in undulators.

  19. Measurement of returns to scale in radial DEA models

    NASA Astrophysics Data System (ADS)

    Krivonozhko, V. E.; Lychev, A. V.; Førsund, F. R.

    2017-01-01

    A general approach is proposed in order to measure returns to scale and scale elasticity at projections points in the radial data envelopment analysis (DEA) models. In the first stage, a relative interior point belonging to the optimal face is found using a special, elaborated method. In previous work it was proved that any relative interior point of a face has the same returns to scale as any other interior point of this face. In the second stage, we propose to determine the returns to scale at the relative interior point found in the first stage.

  20. Radial flow nuclear thermal rocket (RFNTR)

    DOEpatents

    Leyse, Carl F.

    1995-01-01

    A radial flow nuclear thermal rocket fuel assembly includes a substantially conical fuel element having an inlet side and an outlet side. An annular channel is disposed in the element for receiving a nuclear propellant, and a second, conical, channel is disposed in the element for discharging the propellant. The first channel is located radially outward from the second channel, and separated from the second channel by an annular fuel bed volume. This fuel bed volume can include a packed bed of loose fuel beads confined by a cold porous inlet frit and a hot porous exit frit. The loose fuel beads include ZrC coated ZrC-UC beads. In this manner, nuclear propellant enters the fuel assembly axially into the first channel at the inlet side of the element, flows axially across the fuel bed volume, and is discharged from the assembly by flowing radially outward from the second channel at the outlet side of the element.

  1. Radial flow nuclear thermal rocket (RFNTR)

    DOEpatents

    Leyse, Carl F.

    1995-11-07

    A radial flow nuclear thermal rocket fuel assembly includes a substantially conical fuel element having an inlet side and an outlet side. An annular channel is disposed in the element for receiving a nuclear propellant, and a second, conical, channel is disposed in the element for discharging the propellant. The first channel is located radially outward from the second channel, and separated from the second channel by an annular fuel bed volume. This fuel bed volume can include a packed bed of loose fuel beads confined by a cold porous inlet frit and a hot porous exit frit. The loose fuel beads include ZrC coated ZrC-UC beads. In this manner, nuclear propellant enters the fuel assembly axially into the first channel at the inlet side of the element, flows axially across the fuel bed volume, and is discharged from the assembly by flowing radially outward from the second channel at the outlet side of the element.

  2. Precise Near-Infrared Radial Velocities

    NASA Astrophysics Data System (ADS)

    Plavchan, Peter; Gao, P.; Bottom, M.; Davison, C.; Mills, S.; Ciardi, D. R.; Brinkworth, C.; Tanner, A. M.; Beichman, C. A.; Catanzarite, J.; Crawford, S.; Wallace, J.; Mennesson, B.; Johnson, J. A.; White, R. J.; Anglada-Escudé, G.; von Braun, K.; Walp, B.; Vasisht, G.; Kane, S. R.; Prato, L. A.; NIRRVs

    2014-01-01

    We present precise radial velocity time-series from a 2.3 micron pilot survey to detect exoplanets around red, low mass, and young stars. We use the CSHELL spectrograph with an isotopic methane absorption gas cell for common optical path relative wavelength calibration at the NASA InfraRed Telescope Facility. We present an overview of our Nelder-Mead simplex optimization pipeline for extracting radial velocities. We will also present first light data at 1.6 microns from a near-infrared fiber scrambler used in tandem with our gas cell and CSHELL at IRTF. The fiber scrambler makes use of non-circular core fibers to stabilize the illumination of the slit and echelle grating against changes in seeing, focus, guiding and other sources of systematic radial velocity noise, complementing the wavelength calibration of a gas cell.

  3. Manufacturing of Precision Forgings by Radial Forging

    NASA Astrophysics Data System (ADS)

    Wallner, S.; Harrer, O.; Buchmayr, B.; Hofer, F.

    2011-01-01

    Radial forging is a multi purpose incremental forging process using four tools on the same plane. It is widely used for the forming of tool steels, super alloys as well as titanium- and refractory metals. The range of application goes from reducing the diameters of shafts, tubes, stepped shafts and axels, as well as for creating internal profiles for tubes in Near-Net-Shape and Net-Shape quality. Based on actual development of a weight optimized transmission input shaft, the specific features of radial forging technology is demonstrated. Also a Finite Element Model for the simulation of the process is shown which leads to reduced pre-processing effort and reduced computing time compared to other published simulation methods for radial forging. The finite element model can be applied to quantify the effects of different forging strategies.

  4. Dispersion-free radial transmission lines

    DOEpatents

    Caporaso, George J.; Nelson, Scott D.

    2011-04-12

    A dispersion-free radial transmission line ("DFRTL") preferably for linear accelerators, having two plane conductors each with a central hole, and an electromagnetically permeable material ("EPM") between the two conductors and surrounding a channel connecting the two holes. At least one of the material parameters of relative magnetic permeability, relative dielectric permittivity, and axial width of the EPM is varied as a function of radius, so that the characteristic impedance of the DFRTL is held substantially constant, and pulse transmission therethrough is substantially dispersion-free. Preferably, the EPM is divided into concentric radial sections, with the varied material parameters held constant in each respective section but stepwise varied between sections as a step function of the radius. The radial widths of the concentric sections are selected so that pulse traversal time across each section is the same, and the varied material parameters of the concentric sections are selected to minimize traversal error.

  5. Radial anisotropy ambient noise tomography of volcanoes

    NASA Astrophysics Data System (ADS)

    Mordret, Aurélien; Rivet, Diane; Shapiro, Nikolai; Jaxybulatov, Kairly; Landès, Matthieu; Koulakov, Ivan; Sens-Schönfelder, Christoph

    2016-04-01

    The use of ambient seismic noise allows us to perform surface-wave tomography of targets which could hardly be imaged by other means. The frequencies involved (~ 0.5 - 20 s), somewhere in between active seismic and regular teleseismic frequency band, make possible the high resolution imaging of intermediate-size targets like volcanic edifices. Moreover, the joint inversion of Rayleigh and Love waves dispersion curves extracted from noise correlations allows us to invert for crustal radial anisotropy. We present here the two first studies of radial anisotropy on volcanoes by showing results from Lake Toba Caldera, a super-volcano in Indonesia, and from Piton de la Fournaise volcano, a hot-spot effusive volcano on the Réunion Island (Indian Ocean). We will see how radial anisotropy can be used to infer the main fabric within a magmatic system and, consequently, its dominant type of intrusion.

  6. Image scanning microscopy with radially polarized light

    NASA Astrophysics Data System (ADS)

    Xiao, Yun; Zhang, Yunhai; Wei, Tongda; Huang, Wei; Shi, Yaqin

    2017-03-01

    In order to improve the resolution of image scanning microscopy, we present a method based on image scanning microscopy and radially polarized light. According to the theory of image scanning microscopy, we get the effective point spread function of image scanning microscopy with the longitudinal component of radially polarized light and a 1 AU detection area, and obtain imaging results of the analyzed samples using this method. Results show that the resolution can be enhanced by 7% compared with that in image scanning microscopy with circularly polarized light, and is 1.54-fold higher than that in confocal microscopy with a pinhole of 1 AU. Additionally, the peak intensity of ISM is 1.54-fold higher than that of a confocal microscopy with a pinhole of 1 AU. In conclusion, the combination of the image scanning microscopy and the radially polarized light could improve the resolution, and it could realize high-resolution and high SNR imaging at the same time.

  7. Mapping radial features in Saturn's rings

    NASA Astrophysics Data System (ADS)

    Tiscareno, Matthew S.; Harris, B. E.

    2013-10-01

    We have carried out a comprehensive survey of the best Cassini ISS data of Saturn's main rings for the purpose of cataloguing all observed spiral density waves, spiral bending waves, and other radial and quasi-radial ring structure. Our survey has revealed a number of new features, including the first known resonant waves raised by Enceladus and Hyperion, thus increasing the number of points at which the local surface density and viscosity of the rings can be measured (cf. Tiscareno et al. 2007, Icarus). We also catalogue several wave-like features whose cause is unknown. Although images of the rings taken by the Imaging Science Subsystem (ISS) are not nominally as high-resolution as the best stellar and radio occultations, they are capable of superior signal-to-noise because of the co-adding inherent in converting a 2-D image into a 1-D "radial scan." In this common technique, as many as a thousand pixels at a given radial distance from Saturn are combined to produce a single characteristic brightness for each radial location. This process suppresses local structure, azimuthal structure, and random noise, all of which commonly decrease the sensitivity of high-resolution occultations, and causes ISS to be the optimal Cassini instrument for detecting a certain class of low-amplitude features. Finally, we employ wavelet techniques (cf. Tiscareno et al. 2007, Icarus) to elucidate subtle periodic and quasi-periodic features in the radial scan data. We will present our results in the context of a ranking of known perturbations in the rings by their resonant torque (updating Lissauer and Cuzzi 1982, AJ). We will identify the strongest expected perturbations that do not appear, and discuss whether the absence is likely to reflect a real limit of ring responsiveness, or (as with previous observations) to reflect sensitivity limits.

  8. Plasma Signatures of Radial Field Power Dropouts

    SciTech Connect

    Lucek, E.A.; Horbury, T.S.; Balogh, A.; McComas, D.J.

    1998-10-04

    A class of small scale structures, with a near-radial magnetic field and a drop in magnetic field fluctuation power, have recently been identified in the polar solar wind. An earlier study of 24 events, each lasting for 6 hours or more, identified no clear plasma signature. In an extension of that work, radial intervals lasting for 4 hours or more (89 in total), have been used to search for a statistically significant plasma signature. It was found that, despite considerable variations between intervals, there was a small but significant drop, on average, in plasma temperature, density and {beta} during these events.

  9. Plasma signatures of radial field power dropouts

    SciTech Connect

    Lucek, E.A.; Balogh, A.; Horbury, T.S.; McComas, D.J.

    1999-06-01

    A class of small scale structures, with a near-radial magnetic field and a drop in magnetic field fluctuation power, have recently been identified in the polar solar wind. An earlier study of 24 events, each lasting for 6 hours or more, identified no clear plasma signature. In an extension of that work, radial intervals lasting for 4 hours or more (89 in total), have been used to search for a statistically significant plasma signature. It was found that, despite considerable variations between intervals, there was a small but significant drop, on average, in plasma temperature, density and {beta} during these events. {copyright} {ital 1999 American Institute of Physics.}

  10. Radial Acceleration Relation in Rotationally Supported Galaxies

    NASA Astrophysics Data System (ADS)

    McGaugh, Stacy S.; Lelli, Federico; Schombert, James M.

    2016-11-01

    We report a correlation between the radial acceleration traced by rotation curves and that predicted by the observed distribution of baryons. The same relation is followed by 2693 points in 153 galaxies with very different morphologies, masses, sizes, and gas fractions. The correlation persists even when dark matter dominates. Consequently, the dark matter contribution is fully specified by that of the baryons. The observed scatter is small and largely dominated by observational uncertainties. This radial acceleration relation is tantamount to a natural law for rotating galaxies.

  11. Reconstruction for Type IV Radial Polydactyly.

    PubMed

    Wall, Lindley B; Goldfarb, Charles A

    2015-09-01

    Type IV radial polydactyly represents a thumb with an extra proximal and distal phalanx. Assessment of the thumb for surgical reconstruction includes observing thumb function, evaluating thumb size and stability, and assessing the first web space. Reconstruction includes excision of the smaller thumb, typically the radial thumb, and re-creating thumb stability and alignment by addressing tendon insertion and joint orientation. Although surgical results are satisfying and complications are uncommon, additional surgical intervention may be required over time owing to thumb malalignment or instability.

  12. Radial Acceleration Relation in Rotationally Supported Galaxies.

    PubMed

    McGaugh, Stacy S; Lelli, Federico; Schombert, James M

    2016-11-11

    We report a correlation between the radial acceleration traced by rotation curves and that predicted by the observed distribution of baryons. The same relation is followed by 2693 points in 153 galaxies with very different morphologies, masses, sizes, and gas fractions. The correlation persists even when dark matter dominates. Consequently, the dark matter contribution is fully specified by that of the baryons. The observed scatter is small and largely dominated by observational uncertainties. This radial acceleration relation is tantamount to a natural law for rotating galaxies.

  13. Aircraft radial-belted tire evaluation

    NASA Technical Reports Server (NTRS)

    Yager, Thomas J.; Stubbs, Sandy M.; Davis, Pamela A.

    1990-01-01

    An overview is given of the ongoing joint NASA/FAA/Industry Surface Traction And Radial Tire (START) Program being conducted at NASA Langley's Aircraft Landing Dynamics Facility (ALDF). The START Program involves tests using three different tire sizes to evaluate tire rolling resistance, braking, and cornering performance throughout the aircraft ground operational speed range for both dry and wet runway surfaces. Preliminary results from recent 40 x 14 size bias-ply, radial-belted, and H-type aircraft tire tests are discussed. The paper concludes with a summary of the current program status and planned ALDF test schedule.

  14. Radial excitations of current-carrying vortices

    NASA Astrophysics Data System (ADS)

    Hartmann, Betti; Michel, Florent; Peter, Patrick

    2017-04-01

    We report on the existence of a new type of cosmic string solutions in the Witten model with U (1) × U (1) symmetry. These solutions are superconducting with radially excited condensates that exist for both gauged and ungauged currents. Our results suggest that these new configurations can be macroscopically stable, but microscopically unstable to radial perturbations. Nevertheless, they might have important consequences for the network evolution and particle emission. We discuss these effects and their possible signatures. We also comment on analogies with non-relativistic condensed matter systems where these solutions may be observable.

  15. Minimal Left-Right Symmetric Dark Matter.

    PubMed

    Heeck, Julian; Patra, Sudhanwa

    2015-09-18

    We show that left-right symmetric models can easily accommodate stable TeV-scale dark matter particles without the need for an ad hoc stabilizing symmetry. The stability of a newly introduced multiplet either arises accidentally as in the minimal dark matter framework or comes courtesy of the remaining unbroken Z_{2} subgroup of B-L. Only one new parameter is introduced: the mass of the new multiplet. As minimal examples, we study left-right fermion triplets and quintuplets and show that they can form viable two-component dark matter. This approach is, in particular, valid for SU(2)×SU(2)×U(1) models that explain the recent diboson excess at ATLAS in terms of a new charged gauge boson of mass 2 TeV.

  16. GCFR radial blanket and shield experiment

    SciTech Connect

    Muckenthaler, F.J.; Hull, J.L.; Manning, J.J.

    1980-12-01

    This report presents integral neutron flux, energy spectra, and gamma-ray heating measurements made for the Radial Blanket and Shield Experiment at the ORNL Tower Shielding Facility as part of a continuing Gas Cooled Fast Breeder Reactor program. The experimental configurations were divided into four basic segments: a spectrum modifier inserted into the Tower Shielding Reactor II beam; blanket slabs consisting of either ThO/sub 2/ or UO/sub 2/ placed directly behind the spectrum modifier; an inner radial shield behind the blankets; and an outer radial shield to complete the mockup. The segments were added in sequence, with selected measurements made within and beyond each segment. The integral experiment was performed to provide verification of calculational methods and nuclear data used in designing a radial shield for the GCFR and determining the effectiveness of the design. The ThO/sub 2/ blanket measurements were needed to bracket the uncertainties in the nuclear cross sections for calculating both the neutron transmission through the blanket and the gamma-ray heating rates within the blanket. Measurements with a UO/sub 2/ blanket were included both as a reference for the ThO/sub 2/ analysis, neutron transmission through UO/sub 2/ having been successfully calculated in previous experiments, and to provide comparison information for other breeder reactor designs.

  17. Extended foil capacitor with radially spoked electrodes

    DOEpatents

    Foster, James C.

    1990-01-01

    An extended foil capacitor has a conductive disk electrically connected in oncrushing contact to the extended foil. A conductive paste is placed through spaces between radial spokes on the disk to electrically and mechanically connect the extended foil to the disk.

  18. Radial-Gap Motor for Ship Propulsion

    NASA Astrophysics Data System (ADS)

    Yanamoto, Toshiyuki; Yokoyama, Minoru

    The KHI team has developed radial gap high-temperature superconducting (HTS) motors of three sizes, 1 MW-class, 3 MW, and 20 MW, to be used for electric propulsion systems for ships. The volumetric torque density of the assembled 3 MW HTS motor was recorded at 40 kNm/m3 in the load test; the world's highest in the class.

  19. Radial velocities of Planetary Nebulae revisited

    NASA Astrophysics Data System (ADS)

    Vázquez, Roberto; Ayala, Sandra A.; Wendolyn Blanco Cárdenas, Mónica; Contreras, María E.; Gómez-Muñoz, Marco Antonio; Guillén, Pedro F.; Olguín, Lorenzo; Ramos-Larios, Gerardo; Sabin, Laurence; Zavala, Saúl A.

    2015-08-01

    We present a new determination of radial velocities of a sample of Galactic Planetary Nebulae (PNe) using a systematic method and the same instrumental setting: the long-slit high-dispersion Manchester Echelle Spectrograph (MES) on the 2.1-m telescope at the San Pedro Mártir Observatory (OAN-SPM; Mexico). This project was inspired by the work of Schneider et al. (1983, A&AS, 52, 399), which has been an important reference during the last decades. Radial velocities of gaseous nebulae can be obtained using the central wavelength of a Gaussian fit, even when there is an expansion velocity, as expected in PNe, but with not enough resolution to see a spectral line splitting. We have used the software SHAPE, a morpho-kinematic modeling and reconstruction tool for astrophysical objects (Steffen et al. 2011, IEEE Trans. Vis. Comput. Graphics, 17, 454), to prove that non-uniform density or brightness, on an expanding shell, can lead to mistaken conclusions about the radial velocity. To determine radial velocities, we only use the spectral data in which a spectral line-splitting is seen, avoiding thus the problem of the possible biased one-Gaussian fit. Cases when this method is not recommended are discussed.This project has been supported by grant PAPIIT-DGAPA-UNAM IN107914. MWB is in grateful receipt of a DGAPA-UNAM postdoctoral scholarship. MAG acknowledges CONACYT for his graduate scholarship.

  20. Determining Enzyme Activity by Radial Diffusion

    ERIC Educational Resources Information Center

    Davis, Bill D.

    1977-01-01

    Discusses advantages of radial diffusion assay in determining presence of enzyme and/or rough approximation of amount of enzyme activities. Procedures are included for the preparation of starch-agar plates, and the application and determination of enzyme. Techniques using plant materials (homogenates, tissues, ungerminated embryos, and seedlings)…

  1. MMICs with Radial Probe Transitions to Waveguides

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Chattopadhyay, Goutam; Pukala, David; Soria, Mary; Fung, King Man; Gaier, Todd; Radisic, Vesna; Lai, Richard

    2009-01-01

    A document presents an update on the innovation reported in Integrated Radial Probe Transition From MMIC to Waveguide (NPO-43957), NASA Tech Briefs Vol. 31, No. 5 (May 2007), page 38. To recapitulate: To enable operation or testing of a monolithic microwave integrated circuit (MMIC), it is necessary to mount the MMIC in a waveguide package that typically has cross-sectional waveguide dimensions of the order of a few hundred microns. A radial probe transition between an MMIC operating at 340 GHz and a waveguide had been designed (but not yet built and tested) to be fabricated as part of a monolithic unit that would include the MMIC. The radial probe could readily be integrated with an MMIC amplifier because the design provided for fabrication of the transition on a substrate of the same material (InP) and thickness (50 m) typical of substrates of MMICs that can operate above 300 GHz. As illustrated in the updated document by drawings, photographs, and plots of test data, the concept has now been realized by designing, fabricating, and testing several MMIC/radial- probe integrated-circuit chips and designing and fabricating a waveguide package to contain each chip.

  2. Left Main Coronary Artery Aneurysm

    PubMed Central

    Doustkami, Hossein; Maleki, Nasrollah; Tavosi, Zahra

    2016-01-01

    Aneurysms of the left main coronary artery are exceedingly rare clinical entities, encountered incidentally in approximately 0.1% of patients who undergo routine angiography. The most common cause of coronary artery aneurysms is atherosclerosis. Angiography is the gold standard for diagnosis and treatment. Depending on the severity of the coexisting coronary stenosis, patients with left main coronary artery aneurysms can be effectively managed either surgically or pharmacologically. We herein report a case of left main coronary artery aneurysm in a 72-year-old man with a prior history of hypertension presenting to our hospital because of unstable angina. The electrocardiogram showed ST-segment depression and T-wave inversion in the precordial leads. All the data of blood chemistry were normal. Echocardiography showed akinetic anterior wall, septum, and apex, mild mitral regurgitation and ejection fraction of 45%. Coronary angiography revealed a saccular aneurysm of the left main coronary artery with significant stenosis in the left anterior descending, left circumflex, and right coronary artery. The patient immediately underwent coronary artery bypass grafting and ligation of the aneurysm. At six months’ follow-up, he remained asymptomatic. PMID:27403190

  3. Radial wave crystals: radially periodic structures from anisotropic metamaterials for engineering acoustic or electromagnetic waves.

    PubMed

    Torrent, Daniel; Sánchez-Dehesa, José

    2009-08-07

    We demonstrate that metamaterials with anisotropic properties can be used to develop a new class of periodic structures that has been named radial wave crystals. They can be sonic or photonic, and wave propagation along the radial directions is obtained through Bloch states like in usual sonic or photonic crystals. The band structure of the proposed structures can be tailored in a large amount to get exciting novel wave phenomena. For example, it is shown that acoustical cavities based on radial sonic crystals can be employed as passive devices for beam forming or dynamically orientated antennas for sound localization.

  4. A Novel Thermal Management Approach for Radial Foil Air Bearings

    DTIC Science & Technology

    2010-07-01

    Rossum (1). Since their discovery, foil bearings have been commonly used as rotor supports in air cycle machines (ACM’s) that are part of an...engines (6, 7). With air as the lubricant, foil bearings can successfully support high speed rotors in extreme temperature environments without the...low enough, can lead to rotor instability. On the other hand, a heavier preload will create higher start-up torque and lift-off speed requirements

  5. A Radial Basis Function Approach to Financial Time Series Analysis

    DTIC Science & Technology

    1993-12-01

    could lead to higher fidelity models in regions of high data density by dropping constraints of obtaining a spatially uniform fit. Finally. it may be...However. we would like to point out the advantage of looking at eliminating multi - pie parameters simultaneously. In RBF networks. for instance, it makes...using the learning networks introduced in Chapter 1. Although not a substitute for the more traditional arbitrage -based pricing formulas, network

  6. Radial forearm free flap morbidity: A rare case of a normal preoperative arteriogram and acute intraoperative hand ischemia.

    PubMed

    Bruner, Terrence W; Hanasono, Matthew M; Skoracki, Roman J

    2011-01-01

    Since its first description in 1981, the radial forearm free flap has become a valuable tool for reconstructive microsurgery. However, there are potential complications associated with the flap - the most feared being hand ischemia from sacrifice of the radial artery. Fortunately, acute ischemic complications are exceedingly rare, with only two cases reported in the literature. Options for preoperative evaluation of the donor extremity include the Allen's test, ultrasonography and angiography. A preoperative arteriogram is considered to be the definitive method to evaluate arterial anatomy, patency, and collateralization between the radial and ulnar arteries. The current article presents the authors' experience with a patient who had a delayed Allen's test and a normal arteriogram of his left upper extremity, and who developed acute intraoperative hand ischemia, requiring reconstruction of his radial artery, after elevation of a radial forearm free flap.Although exceedingly rare, the occurrence of acute vascular insufficiency is always a possibility and must be kept in mind when harvesting a radial forearm free flap. The surgeon should be prepared to perform an interposition vein graft reconstruction to avoid any potential complications. Clinical examination and judgment may be more important than radiological studies in certain cases.

  7. Left atrium segmentation for atrial fibrillation ablation

    NASA Astrophysics Data System (ADS)

    Karim, R.; Mohiaddin, R.; Rueckert, D.

    2008-03-01

    Segmentation of the left atrium is vital for pre-operative assessment of its anatomy in radio-frequency catheter ablation (RFCA) surgery. RFCA is commonly used for treating atrial fibrillation. In this paper we present an semi-automatic approach for segmenting the left atrium and the pulmonary veins from MR angiography (MRA) data sets. We also present an automatic approach for further subdividing the segmented atrium into the atrium body and the pulmonary veins. The segmentation algorithm is based on the notion that in MRA the atrium becomes connected to surrounding structures via partial volume affected voxels and narrow vessels, the atrium can be separated if these regions are characterized and identified. The blood pool, obtained by subtracting the pre- and post-contrast scans, is first segmented using a region-growing approach. The segmented blood pool is then subdivided into disjoint subdivisions based on its Euclidean distance transform. These subdivisions are then merged automatically starting from a seed point and stopping at points where the atrium leaks into a neighbouring structure. The resulting merged subdivisions produce the segmented atrium. Measuring the size of the pulmonary vein ostium is vital for selecting the optimal Lasso catheter diameter. We present a second technique for automatically identifying the atrium body from segmented left atrium images. The separating surface between the atrium body and the pulmonary veins gives the ostia locations and can play an important role in measuring their diameters. The technique relies on evolving interfaces modelled using level sets. Results have been presented on 20 patient MRA datasets.

  8. New Measurements of Radial Mode Eigenfrequencies

    NASA Astrophysics Data System (ADS)

    Laske, G.; Masters, G.; Dziewonski, A. M.

    2001-12-01

    Radial mode eigenfrequencies are commonly thought to be measured with great ease and precision. The reason for this is that these modes have no geographic pattern so one should be able to measure frequencies from a spectrum observed at any station in the world. Yet, radial modes often seem inconsistent with spherical Earth models that fit all other mode frequencies. It turns out that radial modes are sometimes strongly coupled. The strongest coupling is predicted to be with l=2 modes which is caused by the Earth's hydrostatic ellipticity and aspherical structure of harmonic degree 2. In such cases, mode-coupling due to ellipticity alone can cause a frequency shift for the radial modes by more than 4 microHz. Given that mode frequencies can be measured to within 0.1 microHz, this shift is significant, and some singlets of l=2 modes have indeed been misidentified as the radial mode in the past. Including the spectra of the June 23, 2001 Southern Peru Earthquake we have re-analyzed radial mode eigenfrequencies and present a mode dataset that is internally more consistent than previous ones. We construct spherical Earth models that are consistent with our new data, the Earth's mass and moment of inertia and the current best estimates of ``Reference Normal Mode Data'' (available on the Reference Earth Model web site: //mahi.ucsd.edu/Gabi/rem.html). We seek the smallest perturbation to PREM but update the Q-structure as well as the depths of the upper mantle discontinuities (418~km and 660~km as first order discontinuities; 520~km as change in gradient). The best fitting 1D model is transversely isotropic but we also show isotropic models that fit the data to within their errors. We show that the 220~km discontinuity is not required in the isotropic model but that there exists a trade-off between high shear-velocities in the lid and a low-density zone beneath it. We also investigate ways of truncating transverse isotropy without the 220.

  9. [Left pulmonary agenesis diagnosed late].

    PubMed

    Deleanu, Oana; Pătraşcu, Natalia; Nebunoiu, Ana-Maria; Vintilă, V; Ulmeanu, Ruxandra; Mihălţan, F D

    2010-01-01

    We present the case of a 51 years old female-patient, with severe dextroscoliosis, having like unique symptom progressive dyspnea. The blood samples reveals polycythemia, the radiological exam shows the opacification of 2/3 of the left thorax, the absence of the lung structure in the other 1/3, the deviation of the mediastinum, and dextroscoliosis; the computed tomography reveals the absence of the left lung artery and the left airways, compensatory hyperinflation of the right lung and dilatation of the trunk and right pulmonary artery; the bronchoscopy does not visualize the carina or the left main bronchus, typical for pulmonary agenesis. Echocardiography confirmed the absence of left pulmonary artery and shows mild pulmonary hypertension (systolic pressure in the pulmonary artery of 33 mmHg) with dilatation of the right cavities, but good cinetics. We face a case of pulmonary agenesis lately diagnosed, with modest functional cardiologic implications, limited therapeutic options and good survival, justified by the late appearance of the pulmonary hypertension of low severity and without worsening in time.

  10. Multifractal structures in radial velocity measurements for exoplanets

    NASA Astrophysics Data System (ADS)

    Del Sordo, Fabio; Sahil Agarwal, Debra A. Fischer, John S. Wettlaufer

    2015-01-01

    The radial velocity method is a powerful way to search for exoplanetary systems and it led to many discoveries of exoplanets in the last 20 years.Nevertheless, in order observe Earth-like planets, such method needs to be refined, i.e. one needs to improve the signal-to-noise ratio.On one hand this can be achieved by building spectrographs with better performances, but on the other hand it is also central to understand the noise present in the data.Radial-velocity data are time-series which contains the effect of planets as well as of stellar disturbances. Therefore, they are the result of different physical processes which operate on different time-scales, acting in a not always periodic fashionI present here a possible approach to such problem, which consists in looking for multifractal structures in the time-series coming from radial velocity measurements, identifying the underlying long-range correlations and fractal scaling properties, and connecting them to the underlying physical processes, like stellar oscillation, granulation, rotation, and magnetic activity.This method has been previously applied to satellite data related to Arctic sea albedo, relevant for identify trends and noise in the Arctic sea ice (Agarwal, Moon and Wettlaufer, Proc. R. Soc., 2012).Here we use such analysis for exoplanetary data related to possible Earth-like planets.Moreover, we apply the same procedure to synthetic data from numerical simulation of stellar dynamos, which give insight on the mechanism responsible for the noise. In such way we can therefore raise the signal-to-noise ratio in the data using the synthetic data as predicted noise to be subtracted from the observations.

  11. Precise Near-Infrared Radial Velocities

    NASA Astrophysics Data System (ADS)

    Plavchan, Peter; Gao, Peter; Gagne, Jonathan; Furlan, Elise; Brinkworth, Carolyn; Bottom, Michael; Tanner, Angelle; Anglada-Escude, Guillem; White, Russel; Davison, Cassy; Mills, Sean; Beichman, Chas; Johnson, John Asher; Ciardi, David; Wallace, Kent; Mennesson, Bertrand; Vasisht, Gautam; Prato, Lisa; Kane, Stephen; Crawford, Sam; Crawford, Tim; Sung, Keeyoon; Drouin, Brian; Lin, Sean; Leifer, Stephanie; Catanzarite, Joe; Henry, Todd; von Braun, Kaspar; Walp, Bernie; Geneser, Claire; Ogden, Nick; Stufflebeam, Andrew; Pohl, Garrett; Regan, Joe

    2016-01-01

    We present the results of two 2.3 μm near-infrared (NIR) radial velocity (RV) surveys to detect exoplanets around 36 nearby and young M dwarfs. We use the CSHELL spectrograph (R ~ 46,000) at the NASA InfraRed Telescope Facility (IRTF), combined with an isotopic methane absorption gas cell for common optical path relative wavelength calibration. We have developed a sophisticated RV forward modeling code that accounts for fringing and other instrumental artifacts present in the spectra. With a spectral grasp of only 5 nm, we are able to reach long-term radial velocity dispersions of ~20-30 m s-1 on our survey targets.

  12. Lattice radial quantization: 3D Ising

    NASA Astrophysics Data System (ADS)

    Brower, R. C.; Fleming, G. T.; Neuberger, H.

    2013-04-01

    Lattice radial quantization is introduced as a nonperturbative method intended to numerically solve Euclidean conformal field theories that can be realized as fixed points of known Lagrangians. As an example, we employ a lattice shaped as a cylinder with a 2D Icosahedral cross-section to discretize dilatations in the 3D Ising model. Using the integer spacing of the anomalous dimensions of the first two descendants (l = 1, 2), we obtain an estimate for η = 0.034 (10). We also observed small deviations from integer spacing for the 3rd descendant, which suggests that a further improvement of our radial lattice action will be required to guarantee conformal symmetry at the Wilson-Fisher fixed point in the continuum limit.

  13. New radial engine technology from Kongsburg

    SciTech Connect

    Mowill, R.J.; Strom, S.

    1983-01-01

    The first engine of a new family of high performance, rugged radial turbines is presented. The new single shaft 1500 kW site rated KG3 is built upon extensive experience from the field proven KG2 of the same nominal power. The KG3 is being developed both as a simple cycle and recuperated engine providing specific fuel consumptions in the range of 0.29 to 0.19 kg/kW-hr (0.47 to 0.32 lbs/hp-hr). The new Kongsberg engine makes use of a high specific speed high pressure ratio centrifugal compressor combined with a very high tip speed uncooled radial turbine to obtain optimized aerodynamic matching. Several novel design features ar described.

  14. Radial spline assembly for antifriction bearings

    NASA Technical Reports Server (NTRS)

    Moore, Jerry H. (Inventor)

    1993-01-01

    An outer race carrier is constructed for receiving an outer race of an antifriction bearing assembly. The carrier in turn is slidably fitted in an opening of a support wall to accommodate slight axial movements of a shaft. A plurality of longitudinal splines on the carrier are disposed to be fitted into matching slots in the opening. A deadband gap is provided between sides of the splines and slots, with a radial gap at ends of the splines and slots and a gap between the splines and slots sized larger than the deadband gap. With this construction, operational distortions (slope) of the support wall are accommodated by the larger radial gaps while the deadband gaps maintain a relatively high springrate of the housing. Additionally, side loads applied to the shaft are distributed between sides of the splines and slots, distributing such loads over a larger surface area than a race carrier of the prior art.

  15. SpicyNodes Radial Map Engine

    NASA Astrophysics Data System (ADS)

    Douma, M.; Ligierko, G.; Angelov, I.

    2008-10-01

    The need for information has increased exponentially over the past decades. The current systems for constructing, exploring, classifying, organizing, and searching information face the growing challenge of enabling their users to operate efficiently and intuitively in knowledge-heavy environments. This paper presents SpicyNodes, an advanced user interface for difficult interaction contexts. It is based on an underlying structure known as a radial map, which allows users to manipulate and interact in a natural manner with entities called nodes. This technology overcomes certain limitations of existing solutions and solves the problem of browsing complex sets of linked information. SpicyNodes is also an organic system that projects users into a living space, stimulating exploratory behavior and fostering creative thought. Our interactive radial layout is used for educational purposes and has the potential for numerous other applications.

  16. Simple proposal for radial 3D needlets

    NASA Astrophysics Data System (ADS)

    Durastanti, C.; Fantaye, Y.; Hansen, F.; Marinucci, D.; Pesenson, I. Z.

    2014-11-01

    We present here a simple construction of a wavelet system for the three-dimensional ball, which we label radial 3D needlets. The construction envisages a data collection environment in which an observer located at the center of the ball is surrounded by concentric spheres with the same pixelization at different radial distances, for any given resolution. The system is then obtained by weighting the projector operator built on the corresponding set of eigenfunctions and performing a discretization step which turns out to be computationally very convenient. The resulting wavelets can be shown to have very good localization properties in the real and harmonic domain; their implementation is computationally very convenient, and they allow for exact reconstruction as they form a tight frame system. Our theoretical results are supported by an extensive numerical analysis.

  17. Left Hemisphere Dysfunction and Left Hemisphere Overactivation in Schizophrenia

    ERIC Educational Resources Information Center

    Gur, Raquel E.

    1978-01-01

    Reports two studies relating schizophrenia to functional brain asymmetry. The first study found support for the hypothesis of left hemisphere dysfunction in schizophrenia, occurring at a rather early stage of information processing; the second study, using eye directionality as a measure of hemispheric activation, found that schizophrenics…

  18. Si Radial p-i-n Junction Photovoltaic Arrays with Built-In Light Concentrators.

    PubMed

    Yoo, Jinkyoung; Nguyen, Binh-Minh; Campbell, Ian H; Dayeh, Shadi A; Schuele, Paul; Evans, David; Picraux, S Tom

    2015-05-26

    High-performance photovoltaic (PV) devices require strong light absorption, low reflection and efficient photogenerated carrier collection for high quantum efficiency. Previous optical studies of vertical wires arrays have revealed that extremely efficient light absorption in the visible wavelengths is achievable. Photovoltaic studies have further advanced the wire approach by employing radial p-n junction architectures to achieve more efficient carrier collection. While radial p-n junction formation and optimized light absorption have independently been considered, PV efficiencies have further opportunities for enhancement by exploiting the radial p-n junction fabrication procedures to form arrays that simultaneously enhance both light absorption and carrier collection efficiency. Here we report a concept of morphology control to improve PV performance, light absorption and quantum efficiency of silicon radial p-i-n junction arrays. Surface energy minimization during vapor phase epitaxy is exploited to form match-head structures at the tips of the wires. The match-head structure acts as a built-in light concentrator and enhances optical absorptance and external quantum efficiencies by 30 to 40%, and PV efficiency under AM 1.5G illumination by 20% compared to cylindrical structures without match-heads. The design rules for these improvements with match-head arrays are systematically studied. This approach of process-enhanced control of three-dimensional Si morphologies provides a fab-compatible way to enhance the PV performance of Si radial p-n junction wire arrays.

  19. Wavelets, Fractals, and Radial Basis Functions

    DTIC Science & Technology

    2007-11-02

    of Signal Processing. San Diego, CA: Aca- demic, 1998. [13] G. Strang and T. Q. Nguyen, Wavelets and Filter Banks . Cambridge, MA: Wellesley-Cambridge...localization, multiresolution, radial basis functions, re- finement filter , scaling functions, self-similarity, splines, tempered distributions, two-scale...one linear constraint per basis function, and the corresponding linear system of equations is invertible under relatively mild conditions [11]. The

  20. Radial rib antenna surface deviation analysis program

    NASA Technical Reports Server (NTRS)

    Coyner, J. V., Jr.

    1971-01-01

    A digital computer program was developed which analyzes any radial rib antenna with ribs radiating from a central hub. The program has the capability for calculating the antenna surface contour (reversed pillowing effect), the optimum rib shape for minimizing the rms surface error, and the actual rms surface error. Rib deflection due to mesh tension and catenary cable tension can also be compensated for, and the pattern from which the mesh gores are cut can be determined.

  1. The left atrial "Medusa myxoma".

    PubMed

    Williams, Elbert E; Pratt, Jerry W; Martin, David E

    2014-02-01

    Although myxomas are the most commonly seen primary cardiac tumors, encompassing 30% to 50% of all primary tumors of the heart, they remain a rare finding with an annual reported incidence of 0.5 per million. The presenting symptoms of an atrial myxoma are widely varied as are the clinical consequences. Regardless of presentation, once a diagnosis is made prompt surgical excision is recommended to minimize the potential complications of obstruction or embolization. We present the "Medusa myxoma," an arborizing 4-fingered left atrial myxoma extending from the fossa ovalis across the left atrium.

  2. Approximate theory for radial filtration/consolidation

    SciTech Connect

    Tiller, F.M.; Kirby, J.M.; Nguyen, H.L.

    1996-10-01

    Approximate solutions are developed for filtration and subsequent consolidation of compactible cakes on a cylindrical filter element. Darcy`s flow equation is coupled with equations for equilibrium stress under the conditions of plane strain and axial symmetry for radial flow inwards. The solutions are based on power function forms involving the relationships of the solidosity {epsilon}{sub s} (volume fraction of solids) and the permeability K to the solids effective stress p{sub s}. The solutions allow determination of the various parameters in the power functions and the ratio k{sub 0} of the lateral to radial effective stress (earth stress ratio). Measurements were made of liquid and effective pressures, flow rates, and cake thickness versus time. Experimental data are presented for a series of tests in a radial filtration cell with a central filter element. Slurries prepared from two materials (Microwate, which is mainly SrSO{sub 4}, and kaolin) were used in the experiments. Transient deposition of filter cakes was followed by static (i.e., no flow) conditions in the cake. The no-flow condition was accomplished by introducing bentonite which produced a nearly impermeable layer with negligible flow. Measurement of the pressure at the cake surface and the transmitted pressure on the central element permitted calculation of k{sub 0}.

  3. Development of a Radial Deconsolidation Method

    SciTech Connect

    Helmreich, Grant W.; Montgomery, Fred C.; Hunn, John D.

    2015-12-01

    A series of experiments have been initiated to determine the retention or mobility of fission products* in AGR fuel compacts [Petti, et al. 2010]. This information is needed to refine fission product transport models. The AGR-3/4 irradiation test involved half-inch-long compacts that each contained twenty designed-to-fail (DTF) particles, with 20-μm thick carbon-coated kernels whose coatings were deliberately fabricated such that they would crack under irradiation, providing a known source of post-irradiation isotopes. The DTF particles in these compacts were axially distributed along the compact centerline so that the diffusion of fission products released from the DTF kernels would be radially symmetric [Hunn, et al. 2012; Hunn et al. 2011; Kercher, et al. 2011; Hunn, et al. 2007]. Compacts containing DTF particles were irradiated at Idaho National Laboratory (INL) at the Advanced Test Reactor (ATR) [Collin, 2015]. Analysis of the diffusion of these various post-irradiation isotopes through the compact requires a method to radially deconsolidate the compacts so that nested-annular volumes may be analyzed for post-irradiation isotope inventory in the compact matrix, TRISO outer pyrolytic carbon (OPyC), and DTF kernels. An effective radial deconsolidation method and apparatus appropriate to this application has been developed and parametrically characterized.

  4. Left ventricular assist device implantation in patients after left ventricular reconstruction.

    PubMed

    Palmen, Meindert; Braun, Jerry; Beeres, Saskia L M A; Klautz, Robert J M

    2016-12-01

    Left ventricular assist device (LVAD) implantation can be challenging in patients with a prior surgical ventricular restoration (SVR). In this case series of heart failure patients with a history of SVR, we describe the surgical technique and outcome of a customized approach for inflow cannula orientation. Seven patients with a history of SVR with end-stage chronic heart failure were accepted for long-term LVAD support. In all patients, the Dacron patch was removed through left ventriculotomy and a Hegar 22 dilator was inserted at the estimated optimal position of the LVAD inflow cannula. The left ventricle was reconstructed around the dilator from the left ventricular (LV) apex to the base. Finally, the LVAD sewing ring was sutured onto the remaining apical defect and a HeartWare® LVAD was implanted. LVAD implantation was successful in all 7 patients. Transoesophageal echocardiography ensured an adequate LVAD position and inflow and outflow cannula Doppler flow recordings. The mean intensive care unit stay was 5.8 ± 2.6 days, and the hospital stay after surgery was 32 ± 16 days. All patients follow regular visits (follow-up 20 ± 16 months) at the outpatient clinic without any remarkable event. Using the technique described, LVAD implantation in patients after SVR is feasible and safe.

  5. Global existence and boundedness of radial solutions to a two dimensional fully parabolic chemotaxis system with general sensitivity

    NASA Astrophysics Data System (ADS)

    Fujie, Kentarou; Senba, Takasi

    2016-08-01

    This paper deals with positive radially symmetric solutions of the Neumann boundary value problem for the fully parabolic chemotaxis system, {ut=Δu-∇ṡ(u∇χ(v))in Ω×(0,∞),τvt=Δv-v+uin Ω×(0,∞), in a ball Ω \\subset {{{R}}2} with general sensitivity function χ (v) satisfying {χ\\prime}>0 and decaying property {χ\\prime}(s)\\to 0 (s\\to ∞ ), parameter τ \\in ≤ft(0,1\\right] and nonnegative radially symmetric initial data. It is shown that if τ \\in ≤ft(0,1\\right] is sufficiently small, then the problem has a unique classical radially symmetric solution, which exists globally and remains uniformly bounded in time. Especially, this result establishes global existence of solutions in the case χ (v)={χ0}log v for all {χ0}>0 , which has been left as an open problem.

  6. The Radial Velocity Precision of Fiber-fed Spectrographs

    NASA Astrophysics Data System (ADS)

    Walker, Gordon A. H.; Shkolnik, Evgenya; Bohlender, David A.; Yang, Stephenson

    2003-06-01

    We have measured the radial velocities of five 51 Peg-type stars and one star known to be constant in velocity. Our measurements, on 20 Å centered at 3947 Å, were conventional, using Th/Ar comparison spectra taken every 20 or 40 minutes between the stellar exposures. Existing IRAF routines were used for the reduction. We find σRV<=20 m s-1, provided that four measurements (out of 72) with residuals greater than 5 σRV are neglected. The observations were made on five nights with the CFHT Gecko spectrograph (R~110,000), fiber-fed by the CAFE system; σRV<=10 m s-1 seems possible with additional care. This study was incidental to the main observing program and is certainly not exhaustive, but the small value of σRV implies that the fiber feed/image slicer system on Gecko+CAFE essentially eliminates the long-standing problem of guiding errors in radial velocity measurements. We are not promoting this conventional approach for serious Doppler planet searches (especially with Gecko, which has such a small multiplex gain), but the precision is valuable for observations made in spectral regions remote from telluric lines or captive-gas fiducials. Instrument builders might consider the advantages of the CAFE optics, which incorporate agitation and invert the object and pupil to illuminate the slit and grating, respectively, in future spectrograph designs.

  7. Onset of radial flow in p+p collisions

    DOE PAGES

    Jiang, Kun; Zhu, Yinying; Liu, Weitao; ...

    2015-02-23

    It has been debated for decades whether hadrons emerging from p+p collisions exhibit collective expansion. The signal of the collective motion in p+p collisions is not as clear as in heavy-ion collisions because of the low multiplicity and large fluctuation in p+p collisions. Tsallis Blast-Wave (TBW) model is a thermodynamic approach, introduced to handle the overwhelming correlation and fluctuation in the hadronic processes. We have systematically studied the identified particle spectra in p+p collisions from RHIC to LHC using TBW and found no appreciable radial flow in p+p collisions below √s = 900 GeV. At LHC higher energy of 7more » TeV in p+p collisions, the radial flow velocity achieves an average of (β) = 0.320 ± 0.005. This flow velocity is comparable to that in peripheral (40-60%) Au+Au collisions at RHIC. In addition, breaking of the identified particle spectra mT scaling was also observed at LHC from a model independent test.« less

  8. Mutism following left hemisphere infarction.

    PubMed Central

    David, A S; Bone, I

    1984-01-01

    A case of mutism due to left hemisphere infarction is described. Recovery revealed mild motor dysphasia. Review of the literature showed that the case resembles aphemia but is unique by virtue of its duration, and the absence of associated apraxia and paresis. Images PMID:6210346

  9. Intraoperative in situ radial artery conduit flow assessment.

    PubMed

    Canver, Charles C; Yousafzai, Sajjad M

    2008-01-01

    A technique is described for simple flow assessment of the in situ radial artery conduit during coronary bypass via a small incision. This technique allows morphologic and physiologic direct intraoperative assessment of radial artery quality and expands the use of radial artery during coronary artery surgery.

  10. 14 CFR 73.5 - Bearings; radials; miles.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Bearings; radials; miles. 73.5 Section 73.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRSPACE SPECIAL USE AIRSPACE General § 73.5 Bearings; radials; miles. (a) All bearings and radials in this...

  11. 14 CFR 71.7 - Bearings, radials, and mileages.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Bearings, radials, and mileages. 71.7 Section 71.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... REPORTING POINTS § 71.7 Bearings, radials, and mileages. All bearings and radials in this part are true...

  12. 14 CFR 71.7 - Bearings, radials, and mileages.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Bearings, radials, and mileages. 71.7 Section 71.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... REPORTING POINTS § 71.7 Bearings, radials, and mileages. All bearings and radials in this part are true...

  13. 14 CFR 73.5 - Bearings; radials; miles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Bearings; radials; miles. 73.5 Section 73.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRSPACE SPECIAL USE AIRSPACE General § 73.5 Bearings; radials; miles. (a) All bearings and radials in this...

  14. 14 CFR 71.7 - Bearings, radials, and mileages.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Bearings, radials, and mileages. 71.7 Section 71.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... REPORTING POINTS § 71.7 Bearings, radials, and mileages. All bearings and radials in this part are true...

  15. 14 CFR 71.7 - Bearings, radials, and mileages.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Bearings, radials, and mileages. 71.7 Section 71.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... REPORTING POINTS § 71.7 Bearings, radials, and mileages. All bearings and radials in this part are true...

  16. 14 CFR 73.5 - Bearings; radials; miles.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Bearings; radials; miles. 73.5 Section 73.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRSPACE SPECIAL USE AIRSPACE General § 73.5 Bearings; radials; miles. (a) All bearings and radials in this...

  17. 14 CFR 73.5 - Bearings; radials; miles.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Bearings; radials; miles. 73.5 Section 73.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRSPACE SPECIAL USE AIRSPACE General § 73.5 Bearings; radials; miles. (a) All bearings and radials in this...

  18. 14 CFR 71.7 - Bearings, radials, and mileages.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Bearings, radials, and mileages. 71.7 Section 71.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... REPORTING POINTS § 71.7 Bearings, radials, and mileages. All bearings and radials in this part are true...

  19. 14 CFR 73.5 - Bearings; radials; miles.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Bearings; radials; miles. 73.5 Section 73.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRSPACE SPECIAL USE AIRSPACE General § 73.5 Bearings; radials; miles. (a) All bearings and radials in this...

  20. Experimental feasibility study of radial injection cooling of three-pad radial air foil bearings

    NASA Astrophysics Data System (ADS)

    Shrestha, Suman K.

    Air foil bearings use ambient air as a lubricant allowing environment-friendly operation. When they are designed, installed, and operated properly, air foil bearings are very cost effective and reliable solution to oil-free turbomachinery. Because air is used as a lubricant, there are no mechanical contacts between the rotor and bearings and when the rotor is lifted off the bearing, near frictionless quiet operation is possible. However, due to the high speed operation, thermal management is one of the very important design factors to consider. Most widely accepted practice of the cooling method is axial cooling, which uses cooling air passing through heat exchange channels formed underneath the bearing pad. Advantage is no hardware modification to implement the axial cooling because elastic foundation structure of foil bearing serves as a heat exchange channels. Disadvantage is axial temperature gradient on the journal shaft and bearing. This work presents the experimental feasibility study of alternative cooling method using radial injection of cooling air directly on the rotor shaft. The injection speeds, number of nozzles, location of nozzles, total air flow rate are important factors determining the effectiveness of the radial injection cooling method. Effectiveness of the radial injection cooling was compared with traditional axial cooling method. A previously constructed test rig was modified to accommodate a new motor with higher torque and radial injection cooling. The radial injection cooling utilizes the direct air injection to the inlet region of air film from three locations at 120° from one another with each location having three axially separated holes. In axial cooling, a certain axial pressure gradient is applied across the bearing to induce axial cooling air through bump foil channels. For the comparison of the two methods, the same amount of cooling air flow rate was used for both axial cooling and radial injection. Cooling air flow rate was

  1. What Research Tells Us About Left Handedness.

    ERIC Educational Resources Information Center

    Arnold, Rita

    Left handed people have had bad publicity throughout history, and the resulting myths and disadvantages of left handedness have often not been properly dealt with in the classroom. Our language itself maintains a bias against the left, and many other cultures have defined the left as disreputable. Today's life style also provides many physical…

  2. Cladding-pumped ytterbium-doped fiber laser with radially polarized output.

    PubMed

    Lin, Di; Daniel, J M O; Gecevičius, M; Beresna, M; Kazansky, P G; Clarkson, W A

    2014-09-15

    A simple technique for directly generating a radially polarized output beam from a cladding-pumped ytterbium-doped fiber laser is reported. Our approach is based on the use of a nanograting spatially variant waveplate as an intracavity polarization-controlling element. The laser yielded ~32 W of output power (limited by available pump power) with a radially polarized TM (01)-mode output beam at 1040 nm with a corresponding slope efficiency of 66% and a polarization purity of 95%. The beam-propagation factor (M(2)) was measured to be ~1.9-2.1.

  3. Low scale left-right-right-left symmetry

    NASA Astrophysics Data System (ADS)

    Abbas, Gauhar

    2017-01-01

    We propose an effective left-right-right-left model with a parity breaking scale around a few TeV. One of the main achievements of the model is that the mirror fermions as well as the mirror gauge sector simultaneously could be at TeV scale. It is shown that the most dangerous quadratic divergence of the SM Higgs boson involving the top quark in the loop is naturally suppressed, and begins at three loop. The model postpones the fine-tuning of the mass of the SM Higgs boson up to a sufficiently high scale. The model explains the smallness of the neutrino masses whether they are Dirac or Majorana. Furthermore, the strong C P phase is zero in this model.

  4. New technique for treatment of postcatheterization radial artery pseudoaneurysm

    PubMed Central

    Pancholy, Samir B.; Kartashov, Dmitriy S.

    2016-01-01

    We report a new technique for treatment of radial artery pseudoaneurysm (RAP) caused by transradial access (TRA) for coronary angiography. Traditional extrinsic compression with radial flow cessation leads to a local milieu likely associated with an increase in probability of radial artery occlusion (RAO). Our technique involves obtaining ipsilateral radial artery access distal to the neck of the RAP followed by a prolonged sheath dwell time covering the neck of the RAP which allows the RAP sac to thrombose and maintains radial artery lumen patency. © 2016 The Authors. Catheterization and Cardiovascular Interventions Published by Wiley Periodicals, Inc. PMID:27527608

  5. RADIALLY MAGNETIZED PROTOPLANETARY DISK: VERTICAL PROFILE

    SciTech Connect

    Russo, Matthew; Thompson, Christopher

    2015-11-10

    This paper studies the response of a thin accretion disk to an external radial magnetic field. Our focus is on protoplanetary disks (PPDs), which are exposed during their later evolution to an intense, magnetized wind from the central star. A radial magnetic field is mixed into a thin surface layer, wound up by the disk shear, and pushed downward by a combination of turbulent mixing and ambipolar and ohmic drift. The toroidal field reaches much greater strengths than the seed vertical field that is usually invoked in PPD models, even becoming superthermal. Linear stability analysis indicates that the disk experiences the magnetorotational instability (MRI) at a higher magnetization than a vertically magnetized disk when both the effects of ambipolar and Hall drift are taken into account. Steady vertical profiles of density and magnetic field are obtained at several radii between 0.06 and 1 AU in response to a wind magnetic field B{sub r} ∼ (10{sup −4}–10{sup −2})(r/ AU){sup −2} G. Careful attention is given to the radial and vertical ionization structure resulting from irradiation by stellar X-rays. The disk is more strongly magnetized closer to the star, where it can support a higher rate of mass transfer. As a result, the inner ∼1 AU of a PPD is found to evolve toward lower surface density. Mass transfer rates around 10{sup −8} M{sub ⊙} yr{sup −1} are obtained under conservative assumptions about the MRI-generated stress. The evolution of the disk and the implications for planet migration are investigated in the accompanying paper.

  6. Radial stiffness improvement of a flywheel system using multi-surface superconducting levitation

    NASA Astrophysics Data System (ADS)

    Basaran, Sinan; Sivrioglu, Selim

    2017-03-01

    The goal of this research study is the maximization of the levitation force in a flywheel system by the use of more than one permanent magnet with a single ring-shaped HTS material. An analytical model for the radial stiffness of the ring HTS-PM is derived using the frozen image approach. The experimental works are carried out for different polarizations of the permanent magnets, and radial stiffness values are obtained from the radial force measurements. The rotational test of the flywheel system is also realized for different cases. Finally, natural frequencies of the flywheel superconducting magnetic bearing system are experimentally obtained for different combinations of the permanent magnets using a frequency analyzer.

  7. An Energy-Based Method for Computing Radial Stiffness of Single Archimedes Spiral Plane Supporting Spring

    NASA Astrophysics Data System (ADS)

    Zheng, Enlai; Jia, Fang; Lu, Changhui; Chen, He; Ji, Xin

    With space-based adaptive performance of lower stiffness and greater deformation energy, the plane supporting spring finds its wide application in fields like aeronautics, astronautics, etc. In the current study, the radial stiffness formula of a single Archimedes spiral plane supporting spring is derived by means of energy approach, with three key parameters of the supporting spring as independent variables. A series of the supporting spring FEA models are established via APDL speedy modeling. According to the isolation requirements of electronic equipment for a fighter, an example is presented in the form of finite element analysis. The theoretical calculation and analysis data are studied and fitted by MATLAB using the least-square method to obtain the discipline of the radial stiffness of single spiral plane supporting spring with the changes of its three key parameters. The validity of energy-based radial stiffness formula of the spring is confirmed by the comparison between the theoretical calculation and finite element analysis results.

  8. Unusual Presentation of Radial Nerve Entrapment with Lateral Humeral Condyle Fracture – A Case Report

    PubMed Central

    Muthulingam, Manoharan

    2016-01-01

    Lateral humeral condyle fracture is the second most common fracture around the elbow in pediatric age group. Acute neurological deficit as a consequence of nerve injury associated with lateral humeral condyle fractures is very uncommon. We report a rare presentation of a case of lateral humeral condyle fracture in a 13-year-old boy with acute radial nerve palsy. Patient was operated through a modified anterolateral approach to the elbow with, exploration of the radial nerve and internal fixation of the fracture. Complete fracture union at 6 weeks with good range of movements and full neurological recovery at 12 weeks was seen. We report this case due to rare combination of radial nerve injury and lateral humeral condyle fracture. Importance should be given to a thorough neurological examination during initial clinical examination and proper pre-operative planning. PMID:27891411

  9. Evaluation of Previously Cannulated Radial Arteries as Patent Coronary Artery Bypass Conduits.

    PubMed

    Watson, Timothy; Pope, Adele; van Pelt, Niels; Ruygrok, Peter N

    2015-10-01

    In coronary artery bypass grafting, good-quality conduits are needed to maximize the potential for long-term patency. Revascularization has traditionally been achieved with use of the saphenous vein and the internal thoracic arteries. In recent years, total arterial revascularization with use of the radial arteries has been promoted. Meanwhile, use of the transradial approach for coronary angiography has also increased. The long-term effects of previous cannulation in radial artery bypass grafts are not known. Therefore, we used multidetector computed tomographic angiography to investigate radial-artery graft patency in a small series of patients who had undergone transradial angiography. We found a high patency rate, and we discuss those findings here.

  10. Radial basis function networks and complexity regularization in function learning.

    PubMed

    Krzyzak, A; Linder, T

    1998-01-01

    In this paper we apply the method of complexity regularization to derive estimation bounds for nonlinear function estimation using a single hidden layer radial basis function network. Our approach differs from previous complexity regularization neural-network function learning schemes in that we operate with random covering numbers and l(1) metric entropy, making it possible to consider much broader families of activation functions, namely functions of bounded variation. Some constraints previously imposed on the network parameters are also eliminated this way. The network is trained by means of complexity regularization involving empirical risk minimization. Bounds on the expected risk in terms of the sample size are obtained for a large class of loss functions. Rates of convergence to the optimal loss are also derived.

  11. Endoscopic Adipofascial Radial Forearm Flap Reconstruction of a Clival Defect

    PubMed Central

    2016-01-01

    Summary: Skull base surgical defects present unique challenges to anatomic and functional reconstruction. Fortunately, many endonasal skull base defects are successfully managed with a variety of local and regional reconstructive techniques. However, when prior surgery or radiotherapy eliminates the use of these local and regional reconstructive options, more elaborate free tissue transfer techniques are required. Managing endoscopic skull base defects of the anterior cranial fossa and clivus is further complicated by the limited access afforded for flap inset. The following case report describes durable reconstruction of a clival defect with an endoscopically-tunneled adipofascial radial forearm tissue transfer. The case highlights importance of a multidisciplinary surgical team approach with strong foundations in endonasal skull base and reconstructive surgery to achieve successful reconstruction of complex endonasal defects. PMID:27975017

  12. Radial stretch reveals distinct populations of mechanosensitive mammalian somatosensory neurons

    PubMed Central

    Bhattacharya, Martha R. C.; Bautista, Diana M.; Wu, Karin; Haeberle, Henry; Lumpkin, Ellen A.; Julius, David

    2008-01-01

    Primary afferent somatosensory neurons mediate our sense of touch in response to changes in ambient pressure. Molecules that detect and transduce thermal stimuli have been recently identified, but mechanisms underlying mechanosensation, particularly in vertebrate organisms, remain enigmatic. Traditionally, mechanically evoked responses in somatosensory neurons have been assessed one cell at a time by recording membrane currents in response to application of focal pressure, suction, or osmotic challenge. Here, we used radial stretch in combination with live-cell calcium imaging to gain a broad overview of mechanosensitive neuronal subpopulations. We found that different stretch intensities activate distinct subsets of sensory neurons as defined by size, molecular markers, or pharmacological attributes. In all subsets, stretch-evoked responses required extracellular calcium, indicating that mechanical force triggers calcium influx. This approach extends the repertoire of stimulus paradigms that can be used to examine mechanotransduction in mammalian sensory neurons, facilitating future physiological and pharmacological studies. PMID:19060212

  13. Radially leaned outlet guide vanes for fan source noise reduction

    NASA Technical Reports Server (NTRS)

    Kazin, S. B.

    1973-01-01

    Two quiet engine program half scale fans one with a subsonic and the other with a supersonic fan tip speed at takeoff were run with 30 degree leaned and radial outlet guide vanes. Acoustic data at takeoff fan speed on the subsonic tip speed fan showed decreases in 200-foot sideline noise of from 1 to 2 PNdb. The supersonic tip speed fan a takeoff fan speed, however, showed noise increases of up 3 PNdb and a decrease in fan efficiency. At approach fan speed, the subsonic tip speed fan showed a noise decrease of 2.3 PNdb at the 200-foot sideline maximum angle and an increase in efficiency. The supersonic tip speed fan showed noise increase of 3.5 PNdb and no change in efficiency. The decrease in fan efficiency and the nature of the noise increase largely high frequency broadband noise lead to the speculation that an aerodynamic problem occurred.

  14. The phenomenological mechanochemistry of damage and radial cracking

    NASA Astrophysics Data System (ADS)

    Grinfeld, Michael

    2017-01-01

    Traditional damage theory deals with distributed microcracks rather than with individual cracks. In its simplest form, this theory adds just one additional parameter to the set of classical thermodynamic parameters of deformable solids like strain and temperature. Basically, the traditional damage theory reflects only one experimental observation: The elastic moduli become smaller with growing damage. Contrary to the traditional damage theory, the Phenomenological Mechanochemistry of Damage (PMD) uses an energetic approach; it includes, in addition to the bulk elastic energy, the energy associated with braking/recovery of chemical bonds. Therefore, in addition to the elasticity equations, it includes the equation describing evolution/dynamics of chemical bonds. With the minimum amount of physically transparent assumptions, it allows the reproduction of radial cracking patterns that are often observed in experiments and nature. In this paper, we review some earlier results and present the novel ones with emphasis on the electro- or magnetostatics ponderomotive forces.

  15. Real-Time Three-Dimensional Echocardiography as a Novel Approach to Quantify Left Ventricular Dyssynchrony: A Comparison Study with Phase Analysis of Gated Myocardial Perfusion Single Photon Emission Computed Tomography

    PubMed Central

    Marsan, Nina Ajmone; Henneman, Maureen M.; Chen, Ji; Ypenburg, Claudia; Dibbets, Petra; Ghio, Stefano; Bleeker, Gabe B.; Stokkel, Marcel P.; van der Wall, Ernst E.; Tavazzi, Luigi; Garcia, Ernest V.; Bax, Jeroen J.

    2010-01-01

    Background Different imaging modalities have been explored for assessment of left ventricular (LV) dyssynchrony. Gated myocardial perfusion single photon emission computed tomography (GMPS) with phase analysis is a reliable technique to quantify LV dyssynchrony and predict response to cardiac resynchronization therapy. Objective Real-time 3-dimensional echocardiography (RT3DE) is a novel imaging technique that provides a LV systolic dyssynchrony index, based on regional volumetric changes as a function of time and calculated as the SD of time to minimum systolic volume of 16 standard myocardial segments expressed in percentage of cardiac cycle. The aim of this study was to compare LV dyssynchrony evaluated with GMPS with LV dyssynchrony assessed with RT3DE. Methods The study population consisted of 40 patients with heart failure who underwent both GMPS and RT3DE. Results Good correlations between LV dyssynchrony assessed with RT3DE and GMPS were demonstrated (r = 0.76 for histogram bandwidth, r = 0.80 for phase SD, P < .0001). Patients with substantial LV dyssynchrony on GMPS (defined as ≥135 degrees for histogram bandwidth and ≥43 degrees for phase SD) had significantly higher LV systolic dyssynchrony index than patients without substantial LV dyssynchrony. Conclusions The good correlations between LV dyssynchrony assessed with GMPS and with RT3DE provide further support for the use of RT3DE for reliable assessment of LV dyssynchrony. PMID:18222645

  16. Radial velocity measurements in the F corona

    NASA Astrophysics Data System (ADS)

    Beavers, W. I.; Eitter, J. J.; Carr, P. H.; Cook, B. C.

    1980-05-01

    A photoelectric radial velocity spectrometer was employed at the February 26, 1979 total solar eclipse in an attempt to detect motion in the F corona. Multiple dip features were recorded in scans made at points 3.2 and 4.3 solar radii west of the sun. By employing simple dynamic models these observations may be interpreted as evidence of the following two separate components of dust in the inner regions of the solar system: dust moving in prograde orbits outside the region beginning at about four solar radii from the sun, and dust falling into the sun with velocities from about 50 to 250 km/s.

  17. Self-stabilizing radial face seal

    NASA Technical Reports Server (NTRS)

    Etsion, I. (Inventor)

    1981-01-01

    A self-stabilizing radial face seal comprises an axial member and a primary seal ring juxtapositioned to a seal seat. At least one primary seal ring and seal seat unit is affixed to the axial member so as to rotate with it. The primary seal ring has a front face which opposes a face of the seal seat. The seal has both high-pressure and low-pressure regions of fluid, and seal seat is provided with a porous ring-like circumferential structure in the face of the seal seat opposite the front face of the primary seal ring.

  18. Radial Variations in the Io Plasma Torus during the Cassini Era

    NASA Technical Reports Server (NTRS)

    Delamere, P. A.; Bagenal, F.; Steffl, A.

    2005-01-01

    A radial scan through the midnight sector of the Io plasma torus was made by the Cassini Ultraviolet Imaging Spectrograph on 14 January 2001, shortly after closest approach to Jupiter. From these data, Steffl et al. (2004a) derived electron temperature, plasma composition (ion mixing ratios), and electron column density as a function of radius from L = 6 to 0 as well as the total luminosity. We have advanced our homogeneous model of torus physical chemistry (Delamere and Bagenal, 2003) to include latitudinal and radial variations in a manner similar to the two-dimensional model by Schreier et al. (1998). The model variables include: (1) neutral source rate, (2) radial transport coefficient, (3) the hot electron fraction, (4) hot electron temperature, and (5) the neutral O/S ratio. The radial variation of parameters 1-4 are described by simple power laws, making a total of nine parameters. We have explored the sensitivity of the model results to variations in these parameters and compared the best fit with previous Voyager era models (schreier et al., 1998), galileo data (Crary et al., 1998), and Cassini observations (steffl et al., 2004a). We find that radial variations during the Cassini era are consistent with a neutral source rate of 700-1200 kg/s, an integrated transport time from L = 6 to 9 of 100-200 days, and that the core electron temperature is largely determined by a spatially and temporally varying superthermal electron population.

  19. Real-time star identification using synthetic radial pattern and its hardware implementation

    NASA Astrophysics Data System (ADS)

    Zhao, Yang; Wei, Xinguo; Wang, Gangyi; Li, Jian

    2017-02-01

    Star identification algorithm has always been the core strategy of star sensors. For the time being, the identification speed is becoming the bottleneck of satisfying real-time requirements (e.g. high-speed maneuvering applications, power breakdown and so on) on the premise of the robustness. To solve this problem, this paper proposes a novel lost-in-space star identification algorithm based on the synthetic radial pattern, which is dedicated to the pipelined parallel architecture of FPGAs (Field Programmable Gate Arrays). The synthetic radial pattern consists of two single radial patterns connected by their two respective polestars. In the algorithm, the polestar-pair is firstly matched and optimum identification results can be obtained after the follow-up radial pattern filtering. Then, the number of spurious matches can be reduced to a much less level and a mathematical model is also developed to demonstrate the efficiency compared with conventional radial algorithms. Simulations show that the approach is very robust towards various noise conditions and the quantified identification time is less than 1 ms at a low resource cost when it is implemented on FPGA platforms.

  20. Low-frequency ultrasonic Bessel-like collimated beam generation from radial modes of piezoelectric transducers

    NASA Astrophysics Data System (ADS)

    Chillara, Vamshi Krishna; Pantea, Cristian; Sinha, Dipen N.

    2017-02-01

    We present a very simple approach to generate a collimated ultrasonic beam that exploits the natural Bessel-like vibration pattern of the radial modes of a piezoelectric disc with lateral clamping. This eliminates the need for the conventional annular Bessel pattern of the electrodes with individual electrode excitation on the piezo-disc, thus simplifying the transducer design. Numerical and experimental studies are carried out to investigate the Bessel-like vibration patterns of these radial modes showing an excellent agreement between these two studies. Measured ultrasonic beam-profiles in water from the radial modes confirm the profile to be a Bessel beam. Collimated beam generation from radial modes is investigated using a coupled electromechanical finite-element model. It is found that clamping the lateral edges of piezoelectric transducers results in a high-degree of collimation with practically no side-lobes similar to a parametric array beam. Ultrasonic beam-profile measurements in water with both free and clamped piezoelectric transducer are presented. The collimated beam generation using the present technique of using the laterally clamped radial modes finds significant applications in low-frequency imaging through highly attenuating materials.

  1. The left-sided pancreas

    SciTech Connect

    Dunn, G.D.; Gibson, R.N.

    1986-06-01

    Ultrasonography (US) performed in nine patients (two with pancreatic carcinoma, one with hepatomegaly), six with no relevant abdominal disease) showed the pancreas to lie wholly to the left of the aorta. This not uncommon location may give rise to difficulty in demonstrating the pancreas on real-time US scans. The superior mesenteric vessels and splenic vein remain useful land-marks for locating the head of the pancreas in this position.

  2. Radial reactor for trichloroethylene steam reforming

    SciTech Connect

    Moates, F.C.; McMinn, T.E.; Richardson, J.T.

    1999-11-01

    A ceramic foam radial reactor was used to convert trichloroethylene by steam reforming, using 0.5 wt. % Pt as a catalyst. With a quartz enclosure heated externally by infrared lamps, the inlet temperature to the catalyst bed was low enough to suppress pyrolysis, but high conversions (0.99999 +) were achieved at the exit. Stable operation up to 600 h with a space velocity of 5.6 x 10{sup 4}h{sup {minus}1} was achieved, but reactant break-through then occurred, and the catalyst quickly deactivated. Although the deactivated catalyst was regenerated with carbon burning, activity decline was more rapid due to platinum sintering and washcoat degradation. Measured temperature profiles and model calculations indicated a large gradient in the bed and suggested that stable operation could be extended at lower space velocities. Axial temperature profiles were not uniform, since preferential flow occurred in the middle and lower regions of the radial bed. Potential improvements for future designs are suggested.

  3. A radial transmission line material measurement apparatus

    SciTech Connect

    Warne, L.K.; Moyer, R.D.; Koontz, T.E.; Morris, M.E.

    1993-05-01

    A radial transmission line material measurement sample apparatus (sample holder, offset short standards, measurement software, and instrumentation) is described which has been proposed, analyzed, designed, constructed, and tested. The purpose of the apparatus is to obtain accurate surface impedance measurements of lossy, possibly anisotropic, samples at low and intermediate frequencies (vhf and low uhf). The samples typically take the form of sections of the material coatings on conducting objects. Such measurements thus provide the key input data for predictive numerical scattering codes. Prediction of the sample surface impedance from the coaxial input impedance measurement is carried out by two techniques. The first is an analytical model for the coaxial-to-radial transmission line junction. The second is an empirical determination of the bilinear transformation model of the junction by the measurement of three full standards. The standards take the form of three offset shorts (and an additional lossy Salisbury load), which have also been constructed. The accuracy achievable with the device appears to be near one percent.

  4. Hydraulic radial piston pump intake porting arrangement

    SciTech Connect

    Miller, G.T.

    1987-06-16

    This patent describes a hydraulic radial piston pump having a slider block mounted on an eccentric of a rotary shaft in a hydraulic fluid supplied cavity. A piston is mounted in a cylinder disposed radially to the shaft. The piston has a flat working face at one end operating in the cylinder and a flat pad at an opposite end slidably engaged by a flat face of the slider block so as to force the piston outward on a compression stroke on shaft rotation. A yoke retains the piston to the slider block so as to retract the piston inward on an intake stroke on shaft rotation characterized by intake porting means for communicating the cavity with the working end of the piston. It comprises an intake passage extending centrally and axially through the piston from the working end to the pad resulting in an annular face at both piston ends. An elongated intake slot in the face of the slider block extends from a point continuously open to the cavity to a point that opens to the intake passage at the pad end on relative movement of the slider block during the intake stroke to just prior to the compression stroke. The annular faces at the working and pad ends of the piston having substantially equal areas to prevent hydraulic film from developing between the slider block and pad and thereby prevent their separation during compression.

  5. Radial plasma transport in Saturn's magnetosphere (Invited)

    NASA Astrophysics Data System (ADS)

    Hill, T. W.

    2010-12-01

    Radial plasma transport in the magnetosphere of Saturn, like that of Jupiter, is driven by the centrifugal force of (partial) corotation acting on internally generated plasma. A significant difference is that the internal plasma source is evidently broadly distributed throughout the inner magnetosphere of Saturn (4 < L <~12), although the neutral water vapor source is evidently tightly localized to Enceladus (L = 4). At Jupiter, by comparison, both the neutral and plasma sources are evidently largely confined to the Io plasma torus (L ~ 6-7). A possible consequence of the broadly distributed source at Saturn is the observed feature that convective outflow channels are relatively broad and slow, while the corresponding inflow channels are relatively narrow and fast. This feature is well documented by Cassini observations (primarily CAPS and MAG), and reproduced in numerical simulations (RCM) that contain a distributed plasma source, although it has not, to my knowledge, been explained by an analytical theory containing an active plasma source. Both planets exhibit strong magnetospheric modulations near the planetary spin period, probably indicating a persistent longitudinal asymmetry of the radial plasma transport process. At Jupiter such an asymmetry is readily understood as a consequence of the dramatic asymmetry of the intrinsic planetary magnetic field. This is not so at Saturn, where any such field asymmetry is known to be very modest at best. In neither case has the precise nature of the asymmetry been identified either observationally or theoretically.

  6. Radial Infall onto a Massive Molecular Filament

    NASA Astrophysics Data System (ADS)

    Battersby, Cara; Myers, Philip C.; Shirley, Yancy L.; Keto, Eric; Kirk, Helen

    The newly discovered Massive Molecular Filament (MMF) G32.02+0.05 (~ 70 pc long, 105 M⊙) has been shaped and compressed by older generations of massive stars. The similarity of this filament in physical structure (density profile, temperature) to much smaller star-forming filaments, suggests that the mechanism to form such filaments may be a universal process. The densest portion of the filament, apparent as an Infrared Dark Cloud (IRDC) shows a range of massive star formation signatures throughout. We investigate the kinematics in this filament and find widespread inverse P cygni asymmetric line profiles. These line asymmetries are interpreted as a signature of large-scale radial collapse. Using line asymmetries observed with optically thick HCO+ (1-0) and optically thin H13CO+ (1-0) across a range of massive star forming regions in the filament, we estimate the global radial infall rate of the filament to range from a few 100 to a few 1000 M⊙ Myr-1 pc-1. At its current infall rate the densest portions of the cloud will more than double their current mass within a Myr.

  7. Radial stability of anisotropic strange quark stars

    NASA Astrophysics Data System (ADS)

    Arbañil, José D. V.; Malheiro, M.

    2016-11-01

    The influence of the anisotropy in the equilibrium and stability of strange stars is investigated through the numerical solution of the hydrostatic equilibrium equation and the radial oscillation equation, both modified from their original version to include this effect. The strange matter inside the quark stars is described by the MIT bag model equation of state. For the anisotropy two different kinds of local anisotropic σ = pt-pr are considered, where pt and pr are respectively the tangential and the radial pressure: one that is null at the star's surface defined by pr(R) = 0, and one that is nonnull at the surface, namely, σs = 0 and σs ≠ 0. In the case σs = 0, the maximum mass value and the zero frequency of oscillation are found at the same central energy density, indicating that the maximum mass marks the onset of the instability. For the case σs ≠ 0, we show that the maximum mass point and the zero frequency of oscillation coincide in the same central energy density value only in a sequence of equilibrium configurations with the same value of σs. Thus, the stability star regions are determined always by the condition dM/dρc > 0 only when the tangential pressure is maintained fixed at the star surface's pt(R). These results are also quite important to analyze the stability of other anisotropic compact objects such as neutron stars, boson stars and gravastars.

  8. Anastomosis of left to right superior vena cava for repair of unroofed coronary sinus.

    PubMed

    Chihara, Shingo; Yasunaga, Hiroshi; Todo, Kageshige

    2012-04-01

    Left superior vena cava (LSVC) draining into the left atrium is a rare congenital cardiac complex. It may appear as an isolated anomaly or as part of more complex cardiac anomalies. Intraatrial rerouting techniques have been the most common approaches to correcting LSVC drainage into the left atrium in patients without a connecting vein. Although these techniques have proved reliable and successful, there are cases in which extracardiac methods for managing this form of anomalous systemic drainage may be preferable. In the present report, we describe an extracardiac approach to the correction of LSVC draining into the left atrium.

  9. Left Brain/Right Brain Learning for Adult Education.

    ERIC Educational Resources Information Center

    Garvin, Barbara

    1986-01-01

    Contrasts and compares the theory and practice of adult education as it relates to the issue of right brain/left brain learning. The author stresses the need for a whole-brain approach to teaching and suggests that adult educators, given their philosophical directions, are the perfect potential users of this integrated system. (Editor/CT)

  10. Fabricating Radial Groove Gratings Using Projection Photolithography

    NASA Technical Reports Server (NTRS)

    Iazikov, Dmitri; Mossberg, Thomas W.

    2009-01-01

    Projection photolithography has been used as a fabrication method for radial grove gratings. Use of photolithographic method for diffraction grating fabrication represents the most significant breakthrough in grating technology in the last 60 years, since the introduction of holographic written gratings. Unlike traditional methods utilized for grating fabrication, this method has the advantage of producing complex diffractive groove contours that can be designed at pixel-by-pixel level, with pixel size currently at the level of 45 45 nm. Typical placement accuracy of the grating pixels is 10 nm over 30 nm. It is far superior to holographic, mechanically ruled or direct e-beam written gratings and results in high spatial coherence and low spectral cross-talk. Due to the smooth surface produced by reactive ion etch, such gratings have a low level of randomly scattered light. Also, due to high fidelity and good surface roughness, this method is ideally suited for fabrication of radial groove gratings. The projection mask is created using a laser writer. A single crystal silicon wafer is coated with photoresist, and then the projection mask, with its layer of photoresist, is exposed for patterning in a stepper or scanner. To develop the photoresist, the fabricator either removes the exposed areas (positive resist) of the unexposed areas (negative resist). Next, the patterned and developed photoresist silicon substrate is subjected to reactive ion etching. After this step, the substrate is cleaned. The projection mask is fabricated according to electronic design files that may be generated in GDS file format using any suitable CAD (computer-aided design) or other software program. Radial groove gratings in off-axis grazing angle of incidence mount are of special interest for x-ray spectroscopy, as they allow achieving higher spectral resolution for the same grating area and have lower alignment tolerances than traditional in-plane grating scheme. This is especially

  11. Making Tracks on Mars (left-eye)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit has been making tracks on Mars for seven months now, well beyond its original 90-day mission. The rover traveled more than 3 kilometers (2 miles) to reach the 'Columbia Hills' pictured here. In this 360-degree view of the rolling martian terrain, its wheel tracks can be seen approaching from the northwest (right side of image).

    Spirit's navigation camera took the images that make up this mosaic on sols 210 and 213 (Aug. 5 and Aug. 8, 2004). The rover is now conducting scientific studies of the local geology on the 'Clovis' outcrop of the 'West Spur' region of the 'Columbia Hills.' The view is presented in a cylindrical-perspective projection with geometrical seam correction. This is the left-eye view of a stereo pair. Scientists plan for Spirit to take a color panoramic image from this location.

  12. Precise radial velocities in the near infrared

    NASA Astrophysics Data System (ADS)

    Redman, Stephen L.

    Since the first detection of a planet outside our Solar System byWolszczan & Frail (1992), over 500 exoplanets have been found to date2, none of which resemble the Earth. Most of these planets were discovered by measuring the radial velocity (hereafter, RV) of the host star, which wobbles under the gravitational influence of any existing planetary companions. However, this method has yet to achieve the sub-m/s precision necessary to detect an Earth-mass planet in the Habitable Zone (the region around a star that can support liquid water; hereafter, HZ) (Kasting et al. 1993) around a Solar-type star. Even though Kepler (Borucki et al. 2010) has announced several Earth-sized HZ candidates, these targets will be exceptionally difficult to confirm with current astrophysical spectrographs (Borucki et al. 2011). The fastest way to discover and confirm potentiallyhabitable Earth-mass planets is to observe stars with lower masses - in particular, late M dwarfs. While M dwarfs are readily abundant, comprising some 70% of the local stellar population, their low optical luminosity presents a formidable challenge to current optical RV instruments. By observing in the near-infrared (hereafter, NIR), where the flux from M dwarfs peaks, we can potentially reach low RV precisions with significantly less telescope time than would be required by a comparable optical instrument. However, NIR precision RV measurements are a relatively new idea and replete with challenges: IR arrays, unlike CCDs, are sensitive to the thermal background; modal noise is a bigger issue in the NIR than in the optical; and the NIR currently lacks the calibration sources like the very successful thorium-argon (hereafter, ThAr) hollow-cathode lamp and Iodine gas cell of the optical. The PSU Pathfinder (hereafter, Pathfinder) was designed to explore these technical issues with the intention of mitigating these problems for future NIR high-resolution spectrographs, such as the Habitable-Zone Planet Finder (HZPF

  13. Non-radially pulsating Be stars

    NASA Astrophysics Data System (ADS)

    Rivinius, Th.; Baade, D.; Štefl, S.

    2003-11-01

    Based on more than 3000 high-resolution echelle spectra of 27 early-type Be stars, taken over six years, it is shown that the short-term periodic line profile variability of these objects is due to non-radial pulsation. The appearance of the line profile variability depends mostly on the projected rotational velocity v sin i and thus, since all Be stars rotate rapidly, on the inclination i. The observed variability of the investigated stars is described, and for some of them line profile variability periods are given for the first time. For two of the investigated stars the line profile variability was successfully modeled as non-radial pulsation with l=m=+2 already in previous works. Since Be stars with similarly low v sin i share the same variability properties, these are in general explainable under the same model assumptions. The line profile variability of stars with higher v sin i is different from the one observed in low v sin i stars, but can be reproduced by the same model, if only the model inclination is modified to more equatorial values. Only for a few stars with periodic line profile variability the l=m=2 non-radial pulsation mode is not able to provide a satisfying explanation. These objects might pulsate in different modes (e.g. tesseral ones, l != |m|). Almost all stars in the sample show traces of outburst-like variability, pointing to an ephemeral nature of the mass-loss phenomenon responsible for the formation of the circumstellar disk of early-type Be stars, rather than a steady star-to-disk mass transfer. In addition to the variability due to non-radial pulsation present in most stars, several objects were found to show other periods residing in the immediate circumstellar environment. The presence of these secondary periods is enhanced in the outburst phases. Short-lived aperiodic phenomena were clearly seen in two stars. But, given the unfavourable sampling of our database to follow rapid variability of transient nature, they might be more

  14. Facts about Hypoplastic Left Heart Syndrome

    MedlinePlus

    ... working with this defect. After the Baby Is Born Babies with hypoplastic left heart syndrome might not ... a baby with hypoplastic left heart syndrome is born, multiple surgeries done in a particular order are ...

  15. Porcine radial artery decellularization by high hydrostatic pressure.

    PubMed

    Negishi, Jun; Funamoto, Seiichi; Kimura, Tsuyoshi; Nam, Kwangoo; Higami, Tetsuya; Kishida, Akio

    2015-11-01

    Many types of decellularized tissues have been studied and some have been commercially used in clinics. In this study, small-diameter vascular grafts were made using HHP to decellularize porcine radial arteries. One decellularization method, high hydrostatic pressure (HHP), has been used to prepare the decellularized porcine tissues. Low-temperature treatment was effective in preserving collagen and collagen structures in decellularized porcine carotid arteries. The collagen and elastin structures and mechanical properties of HHP-decellularized radial arteries were similar to those of untreated radial arteries. Xenogeneic transplantation (into rats) was performed using HHP-decellularized radial arteries and an untreated porcine radial artery. Two weeks after transplantation into rat carotid arteries, the HHP-decellularized radial arteries were patent and without thrombosis. In addition, the luminal surface of each decellularized artery was covered by recipient endothelial cells and the arterial medium was fully infiltrated with recipient cells.

  16. Radial Shock Wave Devices Generate Cavitation

    PubMed Central

    Császár, Nikolaus B. M.; Angstman, Nicholas B.; Milz, Stefan; Sprecher, Christoph M.; Kobel, Philippe; Farhat, Mohamed; Furia, John P.; Schmitz, Christoph

    2015-01-01

    Background Conflicting reports in the literature have raised the question whether radial extracorporeal shock wave therapy (rESWT) devices and vibrating massage devices have similar energy signatures and, hence, cause similar bioeffects in treated tissues. Methods and Findings We used laser fiber optic probe hydrophone (FOPH) measurements, high-speed imaging and x-ray film analysis to compare fundamental elements of the energy signatures of two rESWT devices (Swiss DolorClast; Electro Medical Systems, Nyon, Switzerland; D-Actor 200; Storz Medical, Tägerwillen, Switzerland) and a vibrating massage device (Vibracare; G5/General Physiotherapy, Inc., Earth City, MO, USA). To assert potential bioeffects of these treatment modalities we investigated the influence of rESWT and vibrating massage devices on locomotion ability of Caenorhabditis elegans (C. elegans) worms. Results FOPH measurements demonstrated that both rESWT devices generated acoustic waves with comparable pressure and energy flux density. Furthermore, both rESWT devices generated cavitation as evidenced by high-speed imaging and caused mechanical damage on the surface of x-ray film. The vibrating massage device did not show any of these characteristics. Moreover, locomotion ability of C. elegans was statistically significantly impaired after exposure to radial extracorporeal shock waves but was unaffected after exposure of worms to the vibrating massage device. Conclusions The results of the present study indicate that both energy signature and bioeffects of rESWT devices are fundamentally different from those of vibrating massage devices. Clinical Relevance Prior ESWT studies have shown that tissues treated with sufficient quantities of acoustic sound waves undergo cavitation build-up, mechanotransduction, and ultimately, a biological alteration that “kick-starts” the healing response. Due to their different treatment indications and contra-indications rESWT devices cannot be equated to vibrating

  17. Radial-Electric-Field Piezoelectric Diaphragm Pumps

    NASA Technical Reports Server (NTRS)

    Bryant, Robert G.; Working, Dennis C.; Mossi, Karla; Castro, Nicholas D.; Mane, Pooma

    2009-01-01

    In a recently invented class of piezoelectric diaphragm pumps, the electrode patterns on the piezoelectric diaphragms are configured so that the electric fields in the diaphragms have symmetrical radial (along-the-surface) components in addition to through-the-thickness components. Previously, it was accepted in the piezoelectric-transducer art that in order to produce the out-of-plane bending displacement of a diaphragm needed for pumping, one must make the electric field asymmetrical through the thickness, typically by means of electrodes placed on only one side of the piezoelectric material. In the present invention, electrodes are placed on both sides and patterned so as to produce substantial radial as well as through-the-thickness components. Moreover, unlike in the prior art, the electric field can be symmetrical through the thickness. Tests have shown in a given diaphragm that an electrode configuration according to this invention produces more displacement than does a conventional one-sided electrode pattern. The invention admits of numerous variations characterized by various degrees of complexity. Figure 1 is a simplified depiction of a basic version. As in other piezoelectric diaphragm pumps of similar basic design, the prime mover is a piezoelectric diaphragm. Application of a suitable voltage to the electrodes on the diaphragm causes it to undergo out-of-plane bending. The bending displacement pushes a fluid out of, or pulls the fluid into, a chamber bounded partly by the diaphragm. Also as in other diaphragm pumps in general, check valves ensure that the fluid flows only in through one port and only out through another port.

  18. New systemic radial velocities of suspected RR Lyrae binary stars

    NASA Astrophysics Data System (ADS)

    Guggenberger, E.; Barnes, T. G.; Kolenberg, K.

    2016-05-01

    Among the tens of thousands of known RR Lyrae stars there are only a handful that show indications of possible binarity. The question why this is the case is still unsolved, and has recently sparked several studies dedicated to the search for additional RR Lyraes in binary systems. Such systems are particularly valuable because they might allow to constrain the stellar mass. Most of the recent studies, however, are based on photometry by finding a light time effect in the timings of maximum light. This approach is a very promising and successful one, but it has a major drawback: by itself, it cannot serve as a definite proof of binarity, because other phenomena such as the Blazhko effect or intrinsic period changes could lead to similar results. Spectroscopic radial velocity measurements, on the other hand, can serve as definite proof of binarity. We have therefore started a project to study spectroscopically RR Lyrae stars that are suspected to be binaries. We have obtained radial velocity (RV) curves with the 2.1m telescope at McDonald observatory. From these we derive systemic RVs which we will compare to previous measurements in order to find changes induced by orbital motions. We also construct templates of the RV curves that can facilitate future studies. We also observed the most promising RR Lyrae binary candidate, TU UMa, as no recent spectroscopic measurements were available. We present a densely covered pulsational RV curve, which will be used to test the predictions of the orbit models that are based on the O - C variations.

  19. Radial energy transport by magnetospheric ULF waves: Effects of magnetic curvature and plasma pressure

    NASA Technical Reports Server (NTRS)

    Kouznetsov, Igor; Lotko, William

    1995-01-01

    The 'radial' transport of energy by internal ULF waves, stimulated by dayside magnetospheric boundary oscillations, is analyzed in the framework of one-fluid magnetohydrodynamics. (the term radial is used here to denote the direction orthogonal to geomagnetic flux surfaces.) The model for the inhomogeneous magnetospheric plasma and background magnetic field is axisymmetric and includes radial and parallel variations in the magnetic field, magnetic curvature, plasma density, and low but finite plasma pressure. The radial mode structure of the coupled fast and intermediate MHD waves is determined by numerical solution of the inhomogeneous wave equation; the parallel mode structure is characterized by a Wentzel-Kramer-Brillouin (WKB) approximation. Ionospheric dissipation is modeled by allowing the parallel wave number to be complex. For boudnary oscillations with frequencies in the range from 10 to 48 mHz, and using a dipole model for the background magnetic field, the combined effects of magnetic curvature and finite plasma pressure are shown to (1) enhance the amplitude of field line resonances by as much as a factor of 2 relative to values obtained in a cold plasma or box-model approximation for the dayside magnetosphere; (2) increase the energy flux delivered to a given resonance by a factor of 2-4; and (3) broaden the spectral width of the resonance by a factor of 2-3. The effects are attributed to the existence of an 'Alfven buoyancy oscillation,' which approaches the usual shear mode Alfven wave at resonance, but unlike the shear Alfven mode, it is dispersive at short perpendicular wavelengths. The form of dispersion is analogous to that of an internal atmospheric gravity wave, with the magnetic tension of the curved background field providing the restoring force and allowing radial propagation of the mode. For nominal dayside parameters, the propagation band of the Alfven buoyancy wave occurs between the location of its (field line) resonance and that of the

  20. Left supraclavicular spindle cell lipoma.

    PubMed

    Olaleye, Oladejo; Fu, Bertram; Moorthy, Ram; Lawson, Charles; Black, Myles; Mitchell, David

    2010-01-01

    Background. Spindle cell lipoma (SCL) is a benign lipomatous tumour, typically occurring in the posterior neck, shoulder or upper back of elderly males. They compose of fat, CD34 positive spindle cells, and ropey collagen on a myxoid matrix. This case highlights a rare presentation of SCL and the need for pre-operative diagnosis. Case Report. A 63-year-old gentleman presented with a pre-existing left supraclavicular mass that had recently increased in size. FNA and CT Scans were performed and results discussed in the mutidisciplinary team meeting. Excisional biopsy was recommended. Radiology. CT neck showed a left supraclavicular mass of fatty density with fine internal septations. A low-grade liposarcoma could not be excluded. Histopathology. FNA was indeterminate. Histology of specimen showed bland spindle cells with no evidence of malignancy. Immuno-histochemistry showed SCL with CD34 positivity and negative staining on CDK4 and p16. Management. Excision biopsy of the mass was performed which was technically difficult as the mass invaginated around the brachial plexus. The patient recovered well post-operatively with no neurological deficits. Conclusion. Spindle cell lipoma is a rare benign tumour and a pre-operative diagnosis based on the clinical context, imaging and immuno-histochemistry is crucial to management.

  1. The influence of acute unloading on left ventricular strain and strain rate by speckle tracking echocardiography in a porcine model.

    PubMed

    Dahle, Geir Olav; Stangeland, Lodve; Moen, Christian Arvei; Salminen, Pirjo-Riitta; Haaverstad, Rune; Matre, Knut; Grong, Ketil

    2016-05-15

    Noninvasive measurements of myocardial strain and strain rate by speckle tracking echocardiography correlate to cardiac contractile state but also to load, which may weaken their value as indices of inotropy. In a porcine model, we investigated the influence of acute dynamic preload reductions on left ventricular strain and strain rate and their relation to the pressure-conductance catheter-derived preload recruitable stroke work (PRSW) and peak positive first derivative of left ventricular pressure (LV-dP/dtmax). Speckle tracking strain and strain rate in the longitudinal, circumferential, and radial directions were measured during acute dynamic reductions of end-diastolic volume during three different myocardial inotropic states. Both strain and strain rate were sensitive to unloading of the left ventricle (P < 0.001), but the load dependency for strain rate was modest compared with strain. Changes in longitudinal and circumferential strain correlated more strongly to changes in end-diastolic volume (r = -0.86 and r = -0.72) than did radial strain (r = 0.35). Longitudinal, circumferential, and radial strain significantly correlated with LV-dP/dtmax (r = -0.53, r = -0.46, and r = 0.86), whereas only radial strain correlated with PRSW (r = 0.55). Strain rate in the longitudinal, circumferential and radial direction significantly correlated with both PRSW (r = -0.64, r = -0.58, and r = 0.74) and LV-dP/dtmax (r = -0.95, r = -0.70, and r = 0.85). In conclusion, the speckle tracking echocardiography-derived strain rate is more robust to dynamic ventricular unloading than strain. Longitudinal and circumferential strain could not predict load-independent contractility. Strain rates, and especially in the radial direction, are good predictors of preload-independent inotropic markers derived from conductance catheter.

  2. Safety of the Las Vegas left-turn display.

    PubMed

    Ozmen, Ozlem; Tian, Zong Z; Gibby, A Reed

    2014-01-01

    This paper provides a safety evaluation of a special protected/permitted left turn signal control (Las Vegas LT Display) that has been implemented in the urbanized area of Las Vegas, Nevada. The Las Vegas LT Display eliminates the yellow trap condition for leading approach in lead/lag operation. It provides protected only left turns during certain times of day by suppressing the permitted green ball and yellow ball displays. Before and after studies were conducted using the crash data from 10 intersections. Results from the analyses indicated that no obvious safety concerns due to use of the special display.

  3. Left-handed Children in Singapore.

    ERIC Educational Resources Information Center

    Gan, Linda

    1998-01-01

    Used teacher questionnaires to examine incidence of left-handedness in nearly 2,800 Singaporean children, racial differences in this left-handed population, and educational provisions in preschool and primary school. Findings indicated that 7.5% of preschoolers and 6.3% of primary children were left-handed, with a higher proportion being Chinese…

  4. The Left-Handed: "Their Sinister" History.

    ERIC Educational Resources Information Center

    Costas, Elaine Fowler

    The history of left-handedness can provide teachers and parents a better understanding of left-handed children and give those children more pride in their difference. No child should be made to feel that he or she is abnormal because of using the left hand, although some specific instruction for these students is necessary in handwriting. Many…

  5. Bilateral Radial Head Fractures in a Woman With Trivial Trauma

    PubMed Central

    Shariff, Zakir; Patel, Kuntal J.; Elbo, A.; Guisasola, I.

    2005-01-01

    Radial head fractures are common injuries, occurring in about 20% of all acute elbow injuries. Isolated radial head fractures are not common and include about 2% of all fractures around the elbow. Bilateral radial head fractures are rare and usually associated with severe trauma and associated fractures and dislocations. We report a case of bilateral undisplaced radial head fracture in a woman, following a simple fall. Early recognition, proper management, and physical therapy led to complete recovery and full functional movement of the elbow. PMID:16369234

  6. An improved equivalent circuit model of radial mode piezoelectric transformer.

    PubMed

    Huang, Yihua; Huang, Wei

    2011-05-01

    In this paper, both the equivalent circuit models of the radial mode and the coupled thickness vibration mode of the radial mode piezoelectric transformer are deduced, and then with the Y-parameter matrix method and the dual-port network theory, an improved equivalent circuit model for the multilayer radial mode piezoelectric transformer is established. A radial mode transformer sample is tested to verify the equivalent circuit model. The experimental results show that the model proposed in this paper is more precise than the typical model.

  7. Robustness of Global Radial Anisotropy Models of the Upper Mantle

    NASA Astrophysics Data System (ADS)

    Xing, Z.; Beghein, C.; Yuan, K.

    2014-12-01

    Radial anisotropy provides important constraints on mantle deformation. While its presence is well accepted in the uppermost mantle, large discrepancies remain among existing models, even at depths well sampled by seismic data, and its presence at greater depths is highly uncertain. Surface wave phase velocity dispersion measurements are routinely used to constrain lateral variations in mantle S-wave velocity (dlnVS) and radial anisotropy (ξ=VSH2/VSV2). Here, we employed the fundamental and higher mode surface wave phase velocity maps of Visser et al. (2008) that have unprecedented sensitivity to structure down to 800-1000km depth, and we adopted a probabilistic forward modeling approach, the Neighbourhood Algorithm, to quantify posterior model uncertainties and parameter trade-offs. We investigated the effect of prior crustal corrections on 3-D ξ and dlnVS models. To avoid mapping crustal structure onto mantle heterogeneities, it is indeed important to accurately account for 3-D crustal anomalies and variations in Moho depth. One approach is to solve the non-linear problem and simultaneously constrain Moho depth and mantle anomalies (Visser et al., 2008). Another approach, taken here, is to calculate non-linear crustal corrections with an a priori crustal model, which are then applied to the phase velocity maps before inverting the remaining signal for mantle structure. In this work, we also determined laterally varying sensitivity kernels to account for lateral changes in the crust. We compare models obtained using CRUST2.0 (Bassin et al., 2000) and the new CRUST1.0 (Laske et al., 2012) models, which mostly differ under continents. Our preliminary results show strong differences (ΔdlnVS>2%) between the two models in continental dlnVS for the upper 150-200km, and strong changes in x amplitudes in the top 200km (Δξ>2%). Some of the differences in ξ persist down to the transition zone, in particular beneath central Asia and South America. Despite these

  8. Interplanetary magnetic field power spectra - Mean field radial or perpendicular to radial

    NASA Technical Reports Server (NTRS)

    Sari, J. W.; Valley, G. C.

    1976-01-01

    A detailed frequency analysis of Pioneer-6 interplanetary magnetic field data is carried out for 5 to 15 hour periods during which the mean interplanetary field is approximately radial or perpendicular to radial. The reason why these data sets were chosen is that by making the usual assumption that the phase speed of any wave present is much less than the mean solar wind speed, the measured frequency spectra can be interpreted in terms of the wave number parallel or perpendicular to the mean field, without such additional assumptions as isotropy or the dominance of a particular mode and without measurements of velocity and density. The details of the calculation of the magnetic field power spectra, coherencies, and correlation functions are discussed, along with results obtained directly from the data (such as spectra, slopes, anisotropies, and coherencies). The results are interpreted in terms of MHD theory, and are related to work in other areas.

  9. Left Hand-assisted Laparoscopic Nephrectomy With Renal Vein Thrombectomy for Stage T3b Renal Cell Carcinoma.

    PubMed

    Ghareeb, George M; Kenleigh, Dorian A; Brown, James A

    2016-04-01

    A 60-year-old male was found to have an 8.0 cm left renal mass and associated renal vein thrombus on computed tomography. The thrombus extended 3 mm beyond the right aortic border to within 1.6 cm of the left border of the inferior vena cava. The patient underwent left nephrectomy with renal vein thrombectomy using a hand-assisted laparoscopic approach. The tumor thrombus was "milked" proximally back into left renal vein, which was then divided with an endovascular stapler. Left renal vein thrombi extending to right margin of the aorta can be managed with hand-assisted laparoscopic approach.

  10. Time efficient aeroelastic simulations based on radial basis functions

    NASA Astrophysics Data System (ADS)

    Liu, Wen; Huang, ChengDe; Yang, Guowei

    2017-02-01

    Aeroelasticity studies the interaction between aerodynamic forces and structural responses, and is one of the fundamental problems to be considered in the design of modern aircraft. The fluid-structure interpolation (FSI) and mesh deformation are two key issues in the CFD-CSD coupling approach (the partitioned approach), which is the mainstream numerical strategy in aeroelastic simulations. In this paper, a time efficient coupling scheme is developed based on the radial basis function interpolations. During the FSI process, the positive definite system of linear equations is constructed with the introduction of pseudo structural forces. The acting forces on the structural nodes can be calculated more efficiently via the solution of the linear system, avoiding the costly computations of the aerodynamic/structural coupling matrix. The multi-layer sequential mesh motion algorithm (MSM) is proposed to improve the efficiency of the volume mesh deformations, which is adequate for large-scale time dependent applications with frequent mesh updates. Two-dimensional mesh motion cases show that the MSM algorithm can reduce the computing cost significantly compared to the standard RBF-based method. The computations of the AGARD 445.6 wing flutter and the static deflections of the three-dimensional high-aspect-ratio aircraft demonstrate that the developed coupling scheme is applicable to both dynamic and static aeroelastic problems.

  11. Left-right entanglement entropy of D p-branes

    NASA Astrophysics Data System (ADS)

    Zayas, Leopoldo A. Pando; Quiroz, Norma

    2016-11-01

    We compute the left-right entanglement entropy for Dp-branes in string theory. We employ the CFT approach to string theory Dp-branes, in particular, its presentation as coherent states of the closed string sector. The entanglement entropy is computed as the von Neumann entropy for a density matrix resulting from integration over the left-moving degrees of freedom. We discuss various crucial ambiguities related to sums over spin structures and argue that different choices capture different physics; however, we advance a themodynamic argument that seems to favor a particular choice of replica. We also consider Dp branes on compact dimensions and verify that the effects of T-duality act covariantly on the Dp brane entanglement entropy. We find that generically the left-right entanglement entropy provides a suitable generalization of boundary entropy and of the D-brane tension.

  12. Mechanics of the left ventricle.

    PubMed

    Chadwick, R S

    1982-09-01

    A theory is presented for the mechanics of the left ventricle. A linear continuum description of the myocardium is developed, which incorporates anisotropic elastic effects due to the fiber direction field. The relation between fiber tension and fiber strain contains a time-dependent activation function that drives the ventricle around its cycle. The theory is applied to a simplified geometry consisting of a thick-walled finite cylinder in which fibers spiral on helical paths and terminate on planar end surfaces. The helix pitch angle varies continuously through the wall. The ventricular cycle is analyzed by specifying the pressures at which the aortic and mitral valves open and close. Key quantities are tabulated which permit a simple determination of the properties of the model under changes of wall thickness, fiber angles, muscle parameters, preload, afterload, etc. It is shown how the active muscle parameters can be inferred from a measurement of the end systolic pressure-volume line.

  13. Giant and thrombosed left ventricular aneurysm.

    PubMed

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-07-26

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention.

  14. Asymptomatic post-rheumatic giant left atrium

    PubMed Central

    Özkartal, Tardu; Tanner, Felix C; Niemann, Markus

    2016-01-01

    A 78-year-old asymptomatic woman was referred to our clinic for a second opinion regarding indication for mitral valve surgery. An echocardiogram showed a moderate mitral stenosis with a concomitant severe regurgitation. The most striking feature, however, was a giant left atrium with a parasternal anteroposterior diameter of 79 mm and a left atrial volume index of 364 mL/m². There are various echocardiographic definitions of a giant left atrium, which are mainly based on measurements of the anteroposterior diameter of the left atrium using M-mode in the parasternal long axis view. Since the commonly accepted method for echocardiographic evaluation of left atrial size is left atrial volume index, we propose a cut-off value of 140 mL/m2 for the definition of a “giant left atrium”. PMID:27354895

  15. Spectrographs for the Measurement of Radial Velocities

    NASA Astrophysics Data System (ADS)

    Baranne, A.

    A radial-velocity measurement derives from a shift in position of spectral features at the focus of a spectrographic instrument. We do not often think about how small these shifts are. It is not generally appreciated that the accuracy to which this shift must be measured is a tiny fraction of a pixel. Or, if we prefer to calculate in microns a surprising minuteness. What precautions should we be taking for the measurement of such small shifts? It is true that, thanks to computers, modern reduction methods allows us to correct for a wide variety of pertubations, provided that these are foreseen and understood; but such reduction procedures will give the best results if such pertubations are kept very small. We must therefore analyse these pertubations and think about how we can control them. The correlation method initiated in its modern form by Roger Griffin, and which we developed further with an optical mask in CORAVEL twenty-five years ago and more recently with a numerical mask in ELODIE, has demonstrated its power. In terms of these methods, the problem of high precision is to improve the correlation peak. Can this be done? Does the correlation method allow us to distinguish the overall radial velocity of the object from possible distortions of the lines? This is certainly a major problem which must be solved. The luminous efficiency of high-precision spectrographs is low. If the use of an optical fibre with scrambling for feeding the spectrograph seems inevitable to us today, it seems to me that the transmission of this system can be considerably improved by a better choice of the F-ratio of the image beam of the telescope which is to be matched with that of the spectrograph. This problem, common to all spectrographs, could be resolved with a specialised focal-plane instrument, giving a much greater than usual F-ratio, resulting in a simplification of the spectrograph optics, and hence an improvement in transmission and a serious decrease in size (which is

  16. Combining axial and radial nanowire heterostructures: radial Esaki diodes and tunnel field-effect transistors.

    PubMed

    Dey, Anil W; Svensson, Johannes; Ek, Martin; Lind, Erik; Thelander, Claes; Wernersson, Lars-Erik

    2013-01-01

    The ever-growing demand on high-performance electronics has generated transistors with very impressive figures of merit (Radosavljevic et al., IEEE Int. Devices Meeting 2009, 1-4 and Cho et al., IEEE Int. Devices Meeting 2011, 15.1.1-15.1.4). The continued scaling of the supply voltage of field-effect transistors, such as tunnel field-effect transistors (TFETs), requires the implementation of advanced transistor architectures including FinFETs and nanowire devices. Moreover, integration of novel materials with high electron mobilities, such as III-V semiconductors and graphene, are also being considered to further enhance the device properties (del Alamo, Nature 2011, 479, 317-323, and Liao et al., Nature 2010, 467, 305-308). In nanowire devices, boosting the drive current at a fixed supply voltage or maintaining a constant drive current at a reduced supply voltage may be achieved by increasing the cross-sectional area of a device, however at the cost of deteriorated electrostatics. A gate-all-around nanowire device architecture is the most favorable electrostatic configuration to suppress short channel effects; however, the arrangement of arrays of parallel vertical nanowires to address the drive current predicament will require additional chip area. The use of a core-shell nanowire with a radial heterojunction in a transistor architecture provides an attractive means to address the drive current issue without compromising neither chip area nor device electrostatics. In addition to design advantages of a radial transistor architecture, we in this work illustrate the benefit in terms of drive current per unit chip area and compare the experimental data for axial GaSb/InAs Esaki diodes and TFETs to their radial counterparts and normalize the electrical data to the largest cross-sectional area of the nanowire, i.e. the occupied chip area, assuming a vertical device geometry. Our data on lateral devices show that radial Esaki diodes deliver almost 7 times higher peak

  17. Ultrashort echo time imaging using pointwise encoding time reduction with radial acquisition (PETRA).

    PubMed

    Grodzki, David M; Jakob, Peter M; Heismann, Bjoern

    2012-02-01

    Sequences with ultrashort echo times enable new applications of MRI, including bone, tendon, ligament, and dental imaging. In this article, a sequence is presented that achieves the shortest possible encoding time for each k-space point, limited by pulse length, hardware switching times, and gradient performance of the scanner. In pointwise encoding time reduction with radial acquisition (PETRA), outer k-space is filled with radial half-projections, whereas the centre is measured single pointwise on a Cartesian trajectory. This hybrid sequence combines the features of single point imaging with radial projection imaging. No hardware changes are required. Using this method, 3D images with an isotropic resolution of 1 mm can be obtained in less than 3 minutes. The differences between PETRA and the ultrashort echo time (UTE) sequence are evaluated by simulation and phantom measurements. Advantages of pointwise encoding time reduction with radial acquisition are shown for tissue with a T(2) below 1 ms. The signal to noise ratio and Contrast-to-noise ratio (CNR) performance, as well as possible limitations of the approach, are investigated. In-vivo head, knee, ankle, and wrist examples are presented to prove the feasibility of the sequence. In summary, fast imaging with ultrashort echo time is enabled by PETRA and may help to establish new routine clinical applications of ultrashort echo time sequences.

  18. Optimal Space Station solar array gimbal angle determination via radial basis function neural networks

    NASA Technical Reports Server (NTRS)

    Clancy, Daniel J.; Oezguener, Uemit; Graham, Ronald E.

    1994-01-01

    The potential for excessive plume impingement loads on Space Station Freedom solar arrays, caused by jet firings from an approaching Space Shuttle, is addressed. An artificial neural network is designed to determine commanded solar array beta gimbal angle for minimum plume loads. The commanded angle would be determined dynamically. The network design proposed involves radial basis functions as activation functions. Design, development, and simulation of this network design are discussed.

  19. A numerical study of the temperature field in a cooled radial turbine rotor

    NASA Technical Reports Server (NTRS)

    Hamed, A.; Baskharone, E.; Tabakoff, W.

    1977-01-01

    The three dimensional temperature distribution in the cooled rotor of a radial inflow turbine is determined numerically using the finite element method. Through this approach, the complicated geometries of the hot rotor and coolant passage surfaces are handled easily, and the temperatures are determined without loss of accuracy at these convective boundaries. Different cooling techniques with given coolant to primary flow ratios are investigated, and the corresponding rotor temperature fields are presented for comparison.

  20. VizieR Online Data Catalog: Radial velocity data of HD 59686 A (Ortiz+, 2016)

    NASA Astrophysics Data System (ADS)

    Ortiz, M.; Reffert, S.; Trifonov, T.; Quirrenbach, A.; Mitchell, D. S.; Nowak, G.; Buenzli, E.; Zimmerman, N.; Bonnefoy, M.; Skemer, A.; Defrere, D.; Lee, M. H.; Fischer, D. A.; Hinz, P. M.

    2016-08-01

    Precise radial velocities of the giant star HD 59686 A are presented. The observations were taken with the Hamilton spectrograph at the Lick Observatory. The data were acquired and reduced using the iodine cell approach. In total, we have 88 RV measurements for HD 59686 A spanning a period of time of around 12 years. Typical exposure times were 20-min, and the signal-to-noise ratios for these observations are about 120-150. (1 data file).

  1. Asymmetrical Cortical Processing of Radial Expansioncontraction in Infants and Adults

    ERIC Educational Resources Information Center

    Shirai, Nobu; Birtles, Deirdre; Wattam-Bell, John; Yamaguchi, Masami K.; Kanazawa, So; Atkinson, Janette; Braddick, Oliver

    2009-01-01

    We report asymmetrical cortical responses (steady-state visual evoked potentials) to radial expansion and contraction in human infants and adults. Forty-four infants (22 3-month-olds and 22 4-month-olds) and nine adults viewed dynamic dot patterns which cyclically (2.1 Hz) alternate between radial expansion (or contraction) and random directional…

  2. Development of an endoscopic probe for radial metrology

    NASA Technical Reports Server (NTRS)

    Gilbert, John A.; Smith, James E., Jr.

    1988-01-01

    The goal of this work was to design and build a prototype for conducting stress analysis and making spectroscopic measurements inside cavities. The objectives were as follows: (1) to develop a prototype for radial profilometry; (2) to explore the possibility of using the radial profilometer for spectroscopic analysis; and (3) to interface the prototype with various combinations of data acquisition and image processing equipment.

  3. The radial defocusing energy-supercritical NLS in dimension four

    NASA Astrophysics Data System (ADS)

    Lu, Chao; Zheng, Jiqiang

    2017-04-01

    We consider the radial defocusing nonlinear Schrödinger equations iut + Δu = | u|p u with supercritical exponent p > 4 in four space dimensions, and prove that any radial solution that remains bounded in the critical Sobolev space must be global and scatter.

  4. Effect of Periradial Administration of Papaverine on Radial Artery Diameter

    PubMed Central

    Nagaraja, P. S.; Singh, Naveen G.; Manjunatha, N.; Desai, Rushikesh Chintamanrao

    2017-01-01

    Background: Radial artery cannulation is a skillful procedure. An experienced anesthesiologist might also face difficulty in cannulating a feeble radial pulse. Aim: The purpose of the study was to determine whether periradial subcutaneous administration of papaverine results in effective vasodilation and improvement in the palpability score of radial artery. Settings and Design: Prospective, double-blinded trial. Methodology: Thirty patients undergoing elective cardiac surgery were enrolled in the study. 30 mg of papaverine with 1 ml of 2% lignocaine and 3 ml of normal saline were injected subcutaneously 1–2 cm proximal to styloid process of the radius. Radial artery diameter before and after 20 min of injection papaverine was measured using ultrasonography. The palpability of the radial pulse was also determined before the injection of papaverine and 20 min later. Patients were monitored for hemodynamics and any complications were noted. Statistical Analysis Used: Student's t-test for paired data. Results: Radial artery diameter increased significantly (P < 0.0001), and the pulse palpability score also showed statistically significant improvement (P < 0.0001) after periradial subcutaneous administration of papaverine. There was no statistically significant difference in heart rate, mean arterial blood pressure before and after papaverine injection. No complications were noted in 24 h of follow-up. Conclusion: Periradial subcutaneous administration of papaverine significantly increased the radial artery diameter and pulse palpability score, which had an impact on ease of radial artery cannulation essential for hemodynamic monitoring in cardiac surgical patients. PMID:28298790

  5. RADIAL VELOCITY VARIABILITY OF FIELD BROWN DWARFS

    SciTech Connect

    Prato, L.; Mace, G. N.; Rice, E. L.; McLean, I. S.; Kirkpatrick, J. Davy; Burgasser, A. J.; Kim, Sungsoo S.

    2015-07-20

    We present paper six of the NIRSPEC Brown Dwarf Spectroscopic Survey, an analysis of multi-epoch, high-resolution (R ∼ 20,000) spectra of 25 field dwarf systems (3 late-type M dwarfs, 16 L dwarfs, and 6 T dwarfs) taken with the NIRSPEC infrared spectrograph at the W. M. Keck Observatory. With a radial velocity (RV) precision of ∼2 km s{sup −1}, we are sensitive to brown dwarf companions in orbits with periods of a few years or less given a mass ratio of 0.5 or greater. We do not detect any spectroscopic binary brown dwarfs in the sample. Given our target properties, and the frequency and cadence of observations, we use a Monte Carlo simulation to determine the detection probability of our sample. Even with a null detection result, our 1σ upper limit for very low mass binary frequency is 18%. Our targets included seven known, wide brown dwarf binary systems. No significant RV variability was measured in our multi-epoch observations of these systems, even for those pairs for which our data spanned a significant fraction of the orbital period. Specialized techniques are required to reach the high precisions sensitive to motion in orbits of very low-mass systems. For eight objects, including six T dwarfs, we present the first published high-resolution spectra, many with high signal to noise, that will provide valuable comparison data for models of brown dwarf atmospheres.

  6. Radial velocities of southern visual multiple stars

    SciTech Connect

    Tokovinin, Andrei; Pribulla, Theodor; Fischer, Debra E-mail: pribulla@ta3.sk

    2015-01-01

    High-resolution spectra of visual multiple stars were taken in 2008–2009 to detect or confirm spectroscopic subsystems and to determine their orbits. Radial velocities of 93 late-type stars belonging to visual multiple systems were measured by numerical cross-correlation. We provide the individual velocities, the width, and the amplitude of the Gaussians that approximate the correlations. The new information on the multiple systems resulting from these data is discussed. We discovered double-lined binaries in HD 41742B, HD 56593C, and HD 122613AB, confirmed several other known subsystems, and constrained the existence of subsystems in some visual binaries where both components turned out to have similar velocities. The orbits of double-lined subsystems with periods of 148 and 13 days are computed for HD 104471 Aa,Ab and HD 210349 Aa,Ab, respectively. We estimate individual magnitudes and masses of the components in these triple systems and update the outer orbit of HD 104471 AB.

  7. Fabrication of cooled radial turbine rotor

    NASA Technical Reports Server (NTRS)

    Hammer, A. N.; Aigret, G. G.; Psichogios, T. P.; Rodgers, C.

    1986-01-01

    A design and fabrication program was conducted to evaluate a unique concept for constructing a cooled, high temperature radial turbine rotor. This concept, called split blade fabrication was developed as an alternative to internal ceramic coring. In this technique, the internal cooling cavity is created without flow dividers or any other detail by a solid (and therefore stronger) ceramic plate which can be more firmly anchored within the casting shell mold than can conventional detailed ceramic cores. Casting is conducted in the conventional manner, except that the finished product, instead of having finished internal cooling passages, is now a split blade. The internal details of the blade are created separately together with a carrier sheet. The inserts are superalloy. Both are produced by essentially the same software such that they are a net fit. The carrier assemblies are loaded into the split blade and the edges sealed by welding. The entire wheel is Hot Isostatic Pressed (HIPed), braze bonding the internal details to the inside of the blades. During this program, two wheels were successfully produced by the split blade fabrication technique.

  8. Camera Calibration with Radial Variance Component Estimation

    NASA Astrophysics Data System (ADS)

    Mélykuti, B.; Kruck, E. J.

    2014-11-01

    Camera calibration plays a more and more important role in recent times. Beside real digital aerial survey cameras the photogrammetric market is dominated by a big number of non-metric digital cameras mounted on UAVs or other low-weight flying platforms. The in-flight calibration of those systems has a significant role to enhance the geometric accuracy of survey photos considerably. It is expected to have a better precision of photo measurements in the center of images then along the edges or in the corners. With statistical methods the accuracy of photo measurements in dependency of the distance of points from image center has been analyzed. This test provides a curve for the measurement precision as function of the photo radius. A high number of camera types have been tested with well penetrated point measurements in image space. The result of the tests led to a general consequence to show a functional connection between accuracy and radial distance and to give a method how to check and enhance the geometrical capability of the cameras in respect to these results.

  9. Experiments of a monolithic radial transmission line

    NASA Astrophysics Data System (ADS)

    Mao, C.; Wang, X.; Zou, X.; Lehr, J.

    2016-11-01

    This paper presents the experimental results of a monolithic radial transmission line (MRTL) that may be used in pulsed power generators and microwave devices. The MRTL with a hyperbolic impedance profile is 508 mm in radius, corresponding to a one-way transit time of 15 ns for the electromagnetic wave. In the experiments, up to twenty identical voltage pulses, 10 ns in FWHM and 2 ns in rise-time, were fed into the MRTL through 20 input BNC connectors that are uniformly distributed along the outer circumference of the MRTL. It was found that the amplitude of the voltage from the output BNC connector located in the center of the MRTL is nearly proportional to the total number of the input branches. The effect of the failure modes on the output voltage was investigated. For the MRTL driven by 20 input branches, while the open-circuit or short-circuit even in one input branch considerably decreases the amplitude of the output voltage, the jitter shorter than 2 ns in 3 input branches makes no obvious effect on the output voltage.

  10. The ITER Radial Neutron Camera Detection System

    SciTech Connect

    Marocco, D.; Belli, F.; Esposito, B.; Petrizzi, L.; Riva, M.; Bonheure, G.; Kaschuck, Y.

    2008-03-12

    A multichannel neutron detection system (Radial Neutron Camera, RNC) will be installed on the ITER equatorial port plug 1 for total neutron source strength, neutron emissivity/ion temperature profiles and n{sub t}/n{sub d} ratio measurements [1]. The system is composed by two fan shaped collimating structures: an ex-vessel structure, looking at the plasma core, containing tree sets of 12 collimators (each set lying on a different toroidal plane), and an in-vessel structure, containing 9 collimators, for plasma edge coverage. The RNC detecting system will work in a harsh environment (neutron fiux up to 10{sup 8}-10{sup 9} n/cm{sup 2} s, magnetic field >0.5 T or in-vessel detectors), should provide both counting and spectrometric information and should be flexible enough to cover the high neutron flux dynamic range expected during the different ITER operation phases. ENEA has been involved in several activities related to RNC design and optimization [2,3]. In the present paper the up-to-date design and the neutron emissivity reconstruction capabilities of the RNC will be described. Different options for detectors suitable for spectrometry and counting (e.g. scintillators and diamonds) focusing on the implications in terms of overall RNC performance will be discussed. The increase of the RNC capabilities offered by the use of new digital data acquisition systems will be also addressed.

  11. Evaluating (and Improving) Estimates of the Solar Radial Magnetic Field Component from Line-of-Sight Magnetograms

    NASA Astrophysics Data System (ADS)

    Leka, K. D.; Barnes, G.; Wagner, E. L.

    2017-02-01

    Although for many solar physics problems the desirable or meaningful boundary is the radial component of the magnetic field Br, the most readily available measurement is the component of the magnetic field along the line of sight to the observer, B_{los}. As this component is only equal to the radial component where the viewing angle is exactly zero, some approximation is required to estimate Br at all other observed locations. In this study, a common approximation known as the "μ-correction", which assumes all photospheric field to be radial, is compared to a method that invokes computing a potential field that matches the observed B_{los}, from which the potential field radial component, Br^{pot} is recovered. We demonstrate that in regions that are truly dominated by a radially oriented field at the resolution of the data employed, the μ-correction performs acceptably if not better than the potential-field approach. However, it is also shown that for any solar structure that includes horizontal fields, i.e. active regions, the potential-field method better recovers both the strength of the radial field and the location of magnetic neutral line.

  12. Molecular identity of human outer radial glia during cortical development.

    PubMed

    Pollen, Alex A; Nowakowski, Tomasz J; Chen, Jiadong; Retallack, Hanna; Sandoval-Espinosa, Carmen; Nicholas, Cory R; Shuga, Joe; Liu, Siyuan John; Oldham, Michael C; Diaz, Aaron; Lim, Daniel A; Leyrat, Anne A; West, Jay A; Kriegstein, Arnold R

    2015-09-24

    Radial glia, the neural stem cells of the neocortex, are located in two niches: the ventricular zone and outer subventricular zone. Although outer subventricular zone radial glia may generate the majority of human cortical neurons, their molecular features remain elusive. By analyzing gene expression across single cells, we find that outer radial glia preferentially express genes related to extracellular matrix formation, migration, and stemness, including TNC, PTPRZ1, FAM107A, HOPX, and LIFR. Using dynamic imaging, immunostaining, and clonal analysis, we relate these molecular features to distinctive behaviors of outer radial glia, demonstrate the necessity of STAT3 signaling for their cell cycle progression, and establish their extensive proliferative potential. These results suggest that outer radial glia directly support the subventricular niche through local production of growth factors, potentiation of growth factor signals by extracellular matrix proteins, and activation of self-renewal pathways, thereby enabling the developmental and evolutionary expansion of the human neocortex.

  13. Assessment of the efficacy of phentolamine to prevent radial artery spasm during cardiac catheterization procedures: a randomized study comparing phentolamine vs. verapamil.

    PubMed

    Ruiz-Salmerón, Rafael J; Mora, Ramón; Masotti, Mónica; Betriu, Amadeo

    2005-10-01

    The objective of this study was to evaluate phentolamine as radial artery spasmolytic in transradial catheterization procedures. Radial artery spasm is a relatively frequent complication during transradial approach, causing patient discomfort or even making it impossible to continue the procedure. As radial artery spasm is mediated by the stimulation of alpha-adrenoreceptors, the use of the alpha-blocker phentolamine could make sense as spasmolytic. We designed a randomized double-blind study to compare phentolamine vs. verapamil, the standard spasmolytic agent. Five hundred patients (250 in each arm) submitted to a transradial cardiac catheterization were consecutively included and randomly assigned to receive 2.5 mg of verapamil or 2.5 mg of phentolamine after sheath insertion. Both vasodilator agents induced a significant radial artery diameter increase (from 2.22 +/- 0.53 to 2.48 +/- 0.57 mm, P < 0.001 for verapamil, and from 2.20 +/- 0.53 to 2.45 +/- 0.53 mm, P < 0.001 for phentolamine). However, verapamil was more efficacious to prevent radial artery spasm (13.2% compared with 23.2% in phentolamine-treated patients; P = 0.004). Follow-up (20 +/- 18 days) evaluation of the radial artery patency by plestismography and pulse oximetry showed no differences between the two groups in the rate of radial occlusion (3.0% vs. 3.2% in verapamil and phentolamine treated patients, respectively). Phentolamine was an effective radial vasodilator agent, although it showed less ability to prevent radial artery spasm than verapamil. Radial artery occlusion rate was almost identical for both vasodilators. Thus, phentolamine could be a valid alternative to verapamil as a radial artery spasmolytic agent.

  14. The Carina Project. IV. Radial Velocity Distribution

    NASA Astrophysics Data System (ADS)

    Fabrizio, M.; Nonino, M.; Bono, G.; Ferraro, I.; François, P.; Iannicola, G.; Monelli, M.; Thévenin, F.; Stetson, P. B.; Walker, A. R.; Buonanno, R.; Caputo, F.; Corsi, C. E.; Dall’Ora, M.; Gilmozzi, R.; James, C. R.; Merle, T.; Pulone, L.; Romaniello, M.

    2011-04-01

    We present new and accurate radial velocity (RV) measurements of luminous stars of all ages (old horizontal branch, intermediate-age red clump, and young blue plume, as well as red giants of a range of ages: 20.6 ≤ V ≤ 22) in the Carina dwarf spheroidal galaxy, based on low-resolution spectra collected with the FORS2 multiobject slit spectrograph at the VLT. This data set was complemented by RV measurements based on medium- and high-resolution archive spectra of brighter (V ≲ 20.6) Carina targets collected with the GIRAFFE multiobject fiber spectrograph at the VLT. The combined sample includes more than 21,340 individual spectra of ≈2000 stars covering the entire body of the galaxy. The mean ( = 220.4 ± 0.1 km s-1) and the dispersion (σ = 11.7 ± 0.1 km s-1) of the RV distribution of candidate Carina stars (∼1210 objects, 180 ≤ RV ≤ 260 km s-1, 4σ) agree quite well with similar measurements available in the literature. To further improve the statistics, the accurate RV measurements recently provided by Walker et al. were also added to the current data set. We ended up with a sample of ∼1370 RV measurements of candidate Carina stars that is ≈75% larger than any previous Carina RV sample. We found that the hypothesis that the Carina RV distribution is Gaussian can be discarded at 99% confidence level. The mean RV across the body of the galaxy varies from ∼220 km s-1 at a distance of 7‧ (∼200 pc) from the center to ∼223 km s-1 at 13‧ (∼400 pc, 6σ level) and flattens out to a constant value of ∼221 km s-1 at larger distances (600 pc, 4σ level). Moreover, and even more importantly, we found that in the Carina regions where the mean RV is smaller, the dispersion is also smaller, and the RV distribution is more centrally peaked (i.e., the kurtosis attains larger values). The difference in mean RV is more than 4 km s-1 (9σ level) when moving from east to west and more than 3 km s-1 (∼7σ level) when moving from north to south

  15. Waves in Radial Gravity Using Magnetic Fluid

    NASA Technical Reports Server (NTRS)

    Ohlsen, D. R.; Hart, J. E.; Weidman, P. D.

    1999-01-01

    Terrestrial laboratory experiments studying various fluid dynamical processes are constrained, by being in an Earth laboratory, to have a gravitational body force which is uniform and unidirectional. Therefore fluid free-surfaces are horizontal and flat. Such free surfaces must have a vertical solid boundary to keep the fluid from spreading horizontally along a gravitational potential surface. In atmospheric, oceanic, or stellar fluid flows that have a horizontal scale of about one-tenth the body radius or larger, sphericity is important in the dynamics. Further, fluids in spherical geometry can cover an entire domain without any sidewall effects, i.e. have truly periodic boundary conditions. We describe spherical body-force laboratory experiments using ferrofluid. Ferrofluids are dilute suspensions of magnetic dipoles, for example magnetite particles of order 10 nm diameter, suspended in a carrier fluid. Ferrofluids are subject to an additional body force in the presence of an applied magnetic field gradient. We use this body force to conduct laboratory experiments in spherical geometry. The present study is a laboratory technique improvement. The apparatus is cylindrically axisymmetric. A cylindrical ceramic magnet is embedded in a smooth, solid, spherical PVC ball. The geopotential field and its gradient, the body force, were made nearly spherical by careful choice of magnet height-to-diameter ratio and magnet size relative to the PVC ball size. Terrestrial gravity is eliminated from the dynamics by immersing the "planet" and its ferrofluid "ocean" in an immiscible silicone oil/freon mixture of the same density. Thus the earth gravity is removed from the dynamics of the ferrofluid/oil interface and the only dynamically active force there is the radial magnetic gravity. The entire apparatus can rotate, and waves are forced on the ferrofluid surface by exterior magnets. The biggest improvement in technique is in the wave visualization. Fluorescing dye is added to

  16. TRUE MASSES OF RADIAL-VELOCITY EXOPLANETS

    SciTech Connect

    Brown, Robert A.

    2015-06-01

    We study the task of estimating the true masses of known radial-velocity (RV) exoplanets by means of direct astrometry on coronagraphic images to measure the apparent separation between exoplanet and host star. Initially, we assume perfect knowledge of the RV orbital parameters and that all errors are due to photon statistics. We construct design reference missions for four missions currently under study at NASA: EXO-S and WFIRST-S, with external star shades for starlight suppression, EXO-C and WFIRST-C, with internal coronagraphs. These DRMs reveal extreme scheduling constraints due to the combination of solar and anti-solar pointing restrictions, photometric and obscurational completeness, image blurring due to orbital motion, and the “nodal effect,” which is the independence of apparent separation and inclination when the planet crosses the plane of the sky through the host star. Next, we address the issue of nonzero uncertainties in RV orbital parameters by investigating their impact on the observations of 21 single-planet systems. Except for two—GJ 676 A b and 16 Cyg B b, which are observable only by the star-shade missions—we find that current uncertainties in orbital parameters generally prevent accurate, unbiased estimation of true planetary mass. For the coronagraphs, WFIRST-C and EXO-C, the most likely number of good estimators of true mass is currently zero. For the star shades, EXO-S and WFIRST-S, the most likely numbers of good estimators are three and four, respectively, including GJ 676 A b and 16 Cyg B b. We expect that uncertain orbital elements currently undermine all potential programs of direct imaging and spectroscopy of RV exoplanets.

  17. Scaling thermal effects in radial flow

    NASA Astrophysics Data System (ADS)

    Hudspeth, R. T.; Guenther, R. B.; Roley, K. L.; McDougal, W. G.

    To adequately evaluate the environmental impact of siting nuclear waste repositories in basalt aquicludes, it is essential to know the effects on parameter identification algorithms of thermal gradients that exist in these basaltic aquicludes. Temperatures of approximately 60°C and pressures of approximately 150 atm can be expected at potential repository sites located at depths of approximately 1000 m. The phenomenon of over-recovery has been observed in some pumping tests conducted at the Hanford Nuclear Reservation located in the Pasco Basin adjacent to the Columbia River in the state of Washington, USA. This over-recovery phenomenon may possibly be due to variations in the fluid density caused by thermal gradients. To assess the potential effects of these thermal gradients on indirect parameter identification algorithms, a systematic scaling of the governing field equations is required in order to obtain dimensionless equations based on the principle of similarity. The constitutive relationships for the specific weight of the fluid and for the porosity of the aquiclude are shown to be exponentially dependent on the pressure gradient. The dynamic pressure is converted to the piezometric head and the flow equation for the piezometric head is then scaled in radial coordinates. Order-of-magnitude estimates are made for all variables in unsteady flow for a typical well test in a basaltic aquiclude. Retaining all nonlinear terms, the parametric dependency of the flow equation on the classical dimensionless thermal and hydraulic parameters is demonstrated. These classical parameters include the Batchelor, Fourier, Froude, Grashof, and Reynolds Numbers associated with thermal flows. The flow equation is linearized from order-of-magnitude estimates based on these classical parameters for application in parameter identification algorithms.

  18. Elongated nanostructures for radial junction solar cells

    NASA Astrophysics Data System (ADS)

    Kuang, Yinghuan; Di Vece, Marcel; Rath, Jatindra K.; van Dijk, Lourens; Schropp, Ruud E. I.

    2013-10-01

    In solar cell technology, the current trend is to thin down the active absorber layer. The main advantage of a thinner absorber is primarily the reduced consumption of material and energy during production. For thin film silicon (Si) technology, thinning down the absorber layer is of particular interest since both the device throughput of vacuum deposition systems and the stability of the devices are significantly enhanced. These features lead to lower cost per installed watt peak for solar cells, provided that the (stabilized) efficiency is the same as for thicker devices. However, merely thinning down inevitably leads to a reduced light absorption. Therefore, advanced light trapping schemes are crucial to increase the light path length. The use of elongated nanostructures is a promising method for advanced light trapping. The enhanced optical performance originates from orthogonalization of the light's travel path with respect to the direction of carrier collection due to the radial junction, an improved anti-reflection effect thanks to the three-dimensional geometric configuration and the multiple scattering between individual nanostructures. These advantages potentially allow for high efficiency at a significantly reduced quantity and even at a reduced material quality, of the semiconductor material. In this article, several types of elongated nanostructures with the high potential to improve the device performance are reviewed. First, we briefly introduce the conventional solar cells with emphasis on thin film technology, following the most commonly used fabrication techniques for creating nanostructures with a high aspect ratio. Subsequently, several representative applications of elongated nanostructures, such as Si nanowires in realistic photovoltaic (PV) devices, are reviewed. Finally, the scientific challenges and an outlook for nanostructured PV devices are presented.

  19. High precision radial velocities with GIANO spectra

    NASA Astrophysics Data System (ADS)

    Carleo, I.; Sanna, N.; Gratton, R.; Benatti, S.; Bonavita, M.; Oliva, E.; Origlia, L.; Desidera, S.; Claudi, R.; Sissa, E.

    2016-06-01

    Radial velocities (RV) measured from near-infrared (NIR) spectra are a potentially excellent tool to search for extrasolar planets around cool or active stars. High resolution infrared (IR) spectrographs now available are reaching the high precision of visible instruments, with a constant improvement over time. GIANO is an infrared echelle spectrograph at the Telescopio Nazionale Galileo (TNG) and it is a powerful tool to provide high resolution spectra for accurate RV measurements of exoplanets and for chemical and dynamical studies of stellar or extragalactic objects. No other high spectral resolution IR instrument has GIANO's capability to cover the entire NIR wavelength range (0.95-2.45 μm) in a single exposure. In this paper we describe the ensemble of procedures that we have developed to measure high precision RVs on GIANO spectra acquired during the Science Verification (SV) run, using the telluric lines as wavelength reference. We used the Cross Correlation Function (CCF) method to determine the velocity for both the star and the telluric lines. For this purpose, we constructed two suitable digital masks that include about 2000 stellar lines, and a similar number of telluric lines. The method is applied to various targets with different spectral type, from K2V to M8 stars. We reached different precisions mainly depending on the H-magnitudes: for H ˜ 5 we obtain an rms scatter of ˜ 10 m s-1, while for H ˜ 9 the standard deviation increases to ˜ 50 ÷ 80 m s-1. The corresponding theoretical error expectations are ˜ 4 m s-1 and 30 m s-1, respectively. Finally we provide the RVs measured with our procedure for the targets observed during GIANO Science Verification.

  20. Scaling laws for radial foil bearings

    NASA Astrophysics Data System (ADS)

    Honavara Prasad, Srikanth

    The effects of fluid pressurization, structural deformation of the compliant members and heat generation in foil bearings make the design and analysis of foil bearings very complicated. The complex fluid-structural-thermal interactions in foil bearings also make modeling efforts challenging because these phenomena are governed by highly non-linear partial differential equations. Consequently, comparison of various bearing designs require detailed calculation of the flow fields (velocities, pressures), bump deflections (structural compliance) and heat transfer phenomena (viscous dissipation in the fluid, frictional heating, temperature profile etc.,) resulting in extensive computational effort (time/hardware). To obviate rigorous computations and aid in feasibility assessments of foil bearings of various sizes, NASA developed the "rule of thumb" design guidelines for estimation of journal bearing load capacity. The guidelines are based on extensive experimental data. The goal of the current work is the development of scaling laws for radial foil bearings to establish an analytical "rule of thumb" for bearing clearance and bump stiffness. The use of scale invariant Reynolds equation and experimentally observed NASA "rule of thumb" yield scale factors which can be deduced from first principles. Power-law relationships between: a. Bearing clearance and bearing radius, and b. bump stiffness and bearing radius, are obtained. The clearance and bump stiffness values obtained from scaling laws are used as inputs for Orbit simulation to study various cases. As the clearance of the bearing reaches the dimensions of the material surface roughness, asperity contact breaks the fluid film which results in wear. Similarly, as the rotor diameter increases (requiring larger bearing diameters), the load capacity of the fluid film should increase to prevent dry rubbing. This imposes limits on the size of the rotor diameter and consequently bearing diameter. Therefore, this thesis aims

  1. Radial Breathing Modes in Cosmochemistry and Meteoritics

    NASA Technical Reports Server (NTRS)

    Wilson, T.L.; Wilson, K.B.

    2009-01-01

    One area of continuing interest in cosmochemistry and meteoritics (C&M) is the identification of the nature of Q-phase, although some researchers in C&M are not reporting relevant portions of Raman spectral data. Q is the unidentified carrier of noble gases in carbonaceous chondrites (CCs). Being carbonaceous, the focus has been on any number of Q-candidates arising from the sp2 hybridization of carbon (C). These all derive from various forms of graphene, a monolayer of C atoms packed into a two-dimensional (2D) hexagonal honeycomb lattice that is the basic building block for graphitic materials of all other dimensions for sp2 allotropes of C. As a basic lattice, 2D graphene can be curled into fullerenes (0D), wrapped into carbon nanotubes or CNTs (1D), and stacked into graphite (3D). These take such additional forms as scroll-like carbon whiskers, carbon fibers, carbon onions, GPCs (graphite polyhedral crystals) [6], and GICs (graphite intercalation compounds). Although all of these have been observed in meteoritics, the issue is which can explain the Q-abundances. In brief, one or more of the 0D-3D sp2 hybridization forms of C is Q. For some Q-candidates, the radial breathing modes (RBMs) are the most important Raman active vibrational modes that exist, and bear a direct relevance to solving this puzzle. Typically in C&M they are ignored when present. Their importance is addressed here as smoking-gun signatures for certain Q-candidates and are very relevant to the ultimate identification of Q.

  2. Elongated nanostructures for radial junction solar cells.

    PubMed

    Kuang, Yinghuan; Vece, Marcel Di; Rath, Jatindra K; Dijk, Lourens van; Schropp, Ruud E I

    2013-10-01

    In solar cell technology, the current trend is to thin down the active absorber layer. The main advantage of a thinner absorber is primarily the reduced consumption of material and energy during production. For thin film silicon (Si) technology, thinning down the absorber layer is of particular interest since both the device throughput of vacuum deposition systems and the stability of the devices are significantly enhanced. These features lead to lower cost per installed watt peak for solar cells, provided that the (stabilized) efficiency is the same as for thicker devices. However, merely thinning down inevitably leads to a reduced light absorption. Therefore, advanced light trapping schemes are crucial to increase the light path length. The use of elongated nanostructures is a promising method for advanced light trapping. The enhanced optical performance originates from orthogonalization of the light's travel path with respect to the direction of carrier collection due to the radial junction, an improved anti-reflection effect thanks to the three-dimensional geometric configuration and the multiple scattering between individual nanostructures. These advantages potentially allow for high efficiency at a significantly reduced quantity and even at a reduced material quality, of the semiconductor material. In this article, several types of elongated nanostructures with the high potential to improve the device performance are reviewed. First, we briefly introduce the conventional solar cells with emphasis on thin film technology, following the most commonly used fabrication techniques for creating nanostructures with a high aspect ratio. Subsequently, several representative applications of elongated nanostructures, such as Si nanowires in realistic photovoltaic (PV) devices, are reviewed. Finally, the scientific challenges and an outlook for nanostructured PV devices are presented.

  3. True Masses of Radial-Velocity Exoplanets

    NASA Astrophysics Data System (ADS)

    Brown, Robert A.

    2015-06-01

    We study the task of estimating the true masses of known radial-velocity (RV) exoplanets by means of direct astrometry on coronagraphic images to measure the apparent separation between exoplanet and host star. Initially, we assume perfect knowledge of the RV orbital parameters and that all errors are due to photon statistics. We construct design reference missions for four missions currently under study at NASA: EXO-S and WFIRST-S, with external star shades for starlight suppression, EXO-C and WFIRST-C, with internal coronagraphs. These DRMs reveal extreme scheduling constraints due to the combination of solar and anti-solar pointing restrictions, photometric and obscurational completeness, image blurring due to orbital motion, and the “nodal effect,” which is the independence of apparent separation and inclination when the planet crosses the plane of the sky through the host star. Next, we address the issue of nonzero uncertainties in RV orbital parameters by investigating their impact on the observations of 21 single-planet systems. Except for two—GJ 676 A b and 16 Cyg B b, which are observable only by the star-shade missions—we find that current uncertainties in orbital parameters generally prevent accurate, unbiased estimation of true planetary mass. For the coronagraphs, WFIRST-C and EXO-C, the most likely number of good estimators of true mass is currently zero. For the star shades, EXO-S and WFIRST-S, the most likely numbers of good estimators are three and four, respectively, including GJ 676 A b and 16 Cyg B b. We expect that uncertain orbital elements currently undermine all potential programs of direct imaging and spectroscopy of RV exoplanets.

  4. Radial Velocity Monitoring of Kepler Heartbeat Stars

    NASA Astrophysics Data System (ADS)

    Shporer, Avi; Fuller, Jim; Isaacson, Howard; Hambleton, Kelly; Thompson, Susan E.; Prša, Andrej; Kurtz, Donald W.; Howard, Andrew W.; O'Leary, Ryan M.

    2016-09-01

    Heartbeat stars (HB stars) are a class of eccentric binary stars with close periastron passages. The characteristic photometric HB signal evident in their light curves is produced by a combination of tidal distortion, heating, and Doppler boosting near orbital periastron. Many HB stars continue to oscillate after periastron and along the entire orbit, indicative of the tidal excitation of oscillation modes within one or both stars. These systems are among the most eccentric binaries known, and they constitute astrophysical laboratories for the study of tidal effects. We have undertaken a radial velocity (RV) monitoring campaign of Kepler HB stars in order to measure their orbits. We present our first results here, including a sample of 22 Kepler HB systems, where for 19 of them we obtained the Keplerian orbit and for 3 other systems we did not detect a statistically significant RV variability. Results presented here are based on 218 spectra obtained with the Keck/HIRES spectrograph during the 2015 Kepler observing season, and they have allowed us to obtain the largest sample of HB stars with orbits measured using a single instrument, which roughly doubles the number of HB stars with an RV measured orbit. The 19 systems measured here have orbital periods from 7 to 90 days and eccentricities from 0.2 to 0.9. We show that HB stars draw the upper envelope of the eccentricity-period distribution. Therefore, HB stars likely represent a population of stars currently undergoing high eccentricity migration via tidal orbital circularization, and they will allow for new tests of high eccentricity migration theories. The data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation.

  5. Evaluation of left ventricular systolic function in young adults with mitral valve prolapse

    PubMed Central

    Malev, Eduard; Zemtsovsky, Eduard; Pshepiy, Asiyet; Timofeev, Eugeny; Reeva, Svetlana; Prokudina, Maria

    2012-01-01

    OBJECTIVE: To evaluate left ventricular function in young adults with mitral valve prolapse (MVP) without significant mitral regurgitation using two-dimensional strain imaging. METHODS AND RESULTS: A total of 58 asymptomatic young subjects (mean [± SD] age 19.7±1.6 years; 72% male) with MVP were compared with 60 sex- and age-matched healthy subjects. MVP was diagnosed by billowing one or both mitral leaflets >2 mm above the mitral annulus in the long-axis parasternal view. Longitudinal, radial and circumferential strain and strain rate were determined using speckle tracking with a grey-scale frame rate of 50 fps to 85 fps. There were no significant differences in the global systolic left ventricular function of the subjects with MVP compared with the control group. In the MVP group, most of the global myocardial systolic deformation indexes were not reduced. Only the global circumferential strain showed a decrease in the prolapse subjects. Regional, longitudinal, circumferential and radial strain and strain rate were decreased only in septal segments. A decrease in the rotation of the same septal segments at the basal level was also observed. CONCLUSION: Regional septal myocardial deformation indexes decrease in subjects with MVP. These changes may be the first sign indicating the deterioration of left ventricular systolic function as well as the existence of primary cardiomyopathy in asymptomatic young subjects with MVP. PMID:23592928

  6. An empirical method that separates irreversible stem radial growth from bark water content changes in trees: theory and case studies.

    PubMed

    Mencuccini, Maurizio; Salmon, Yann; Mitchell, Patrick; Hölttä, Teemu; Choat, Brendan; Meir, Patrick; O'Grady, Anthony; Tissue, David; Zweifel, Roman; Sevanto, Sanna; Pfautsch, Sebastian

    2017-02-01

    Substantial uncertainty surrounds our knowledge of tree stem growth, with some of the most basic questions, such as when stem radial growth occurs through the daily cycle, still unanswered. We employed high-resolution point dendrometers, sap flow sensors, and developed theory and statistical approaches, to devise a novel method separating irreversible radial growth from elastic tension-driven and elastic osmotically driven changes in bark water content. We tested this method using data from five case study species. Experimental manipulations, namely a field irrigation experiment on Scots pine and a stem girdling experiment on red forest gum trees, were used to validate the theory. Time courses of stem radial growth following irrigation and stem girdling were consistent with a-priori predictions. Patterns of stem radial growth varied across case studies, with growth occurring during the day and/or night, consistent with the available literature. Importantly, our approach provides a valuable alternative to existing methods, as it can be approximated by a simple empirical interpolation routine that derives irreversible radial growth using standard regression techniques. Our novel method provides an improved understanding of the relative source-sink carbon dynamics of tree stems at a sub-daily time scale.

  7. Evaluation of a spasmolytic cocktail to prevent radial artery spasm during coronary procedures.

    PubMed

    Kiemeneij, Ferdinand; Vajifdar, Bhavesh U; Eccleshall, Simon C; Laarman, GertJan; Slagboom, Ton; van der Wieken, Ron

    2003-03-01

    Radial artery spasm is a frequent complication of the transradial approach for coronary angiography and angioplasty. Recently, we have been able to quantify spasm using the automatic pullback device. The objective of this study was to assess the efficacy of an intra-arterial vasodilating cocktail in reducing the incidence and severity of radial artery spasm. A hundred patients undergoing coronary procedures via the radial artery were divided into two groups of 50 each. Patients in group A received intra-arterial cocktail (5 mg of verapamil plus 200 micro g nitroglycerine in 10 ml of normal saline), while patients in group B did not receive any vasodilating drug. The pullback device was used for sheath removal at the end of the procedure. Seven (14%) patients in group A experienced pain (i.e., pain score of III-V) during automatic sheath removal, as compared to 17 (34%) in group B (P = 0.019). The mean pain score was significantly lower in group A than in group B (1.7 +/- 0.94 vs. 2.08 +/- 1.07; P = 0.03). The maximal pullback force (MPF) was also significantly lower for group A (0.53 +/- 0.52 kg; range, 0.10-3.03 kg) as compared to group B (0.76 +/- 0.45 kg; range, 0.24-1.99 kg; P = 0.013). Only 4 (8%) patients in group A had an MPF value greater than 1.0 kg, suggesting the presence of significant radial artery spasm, as opposed to 11 (22%) in group B (P = 0.029). Administration of an intra-arterial vasodilating cocktail prior to sheath insertion reduces the occurrence and severity of radial artery spasm.

  8. Measurement of radial artery spasm using an automatic pullback device.

    PubMed

    Kiemeneij, F; Vajifdar, B U; Eccleshall, S C; Laarman, G; Slagboom, T; van der Wieken, R

    2001-12-01

    Current evaluation of radial artery spasm (RAS), a frequent finding during the transradial approach for coronary angiography and angioplasty (TRA), is subjective. A quantitative measure of RAS will help in evaluation and comparison of management strategies. The objectives of the study were to assess the feasibility and safety of using an automatic pullback device (APD) for removal of transradial introducer sheaths and to establish a parameter to quantify RAS. In 50 consecutive transradial procedures, the APD was used to measure the force required for sheath removal. The mean maximal pullback force (MPF) was 0.53 +/- 0.52 kg (range, 0.1-3.0 kg). In 48 (96%) cases, the MPF was reached within the first 5 sec of pullback. All patients with clinical RAS (n = 4) had an MPF greater than 1.0 kg, while the remaining had an MPF less than 1.0 kg. All patients with severe pain during sheath removal (n = 3) had an MPF greater than 1.0 kg, while no patient with an MPF less than 1.0 kg had severe pain. It is feasible and safe to remove transradial introducer sheaths using the APD. The MPF is achieved within the first 5 sec of pullback and is a reliable parameter to quantify RAS. An MPF more than 1.0 kg correlates with clinical RAS and is associated with severe pain during sheath removal.

  9. Automated Freehand Sketch Segmentation Using Radial Basis Functions.

    PubMed

    Pu, Jiantao; Gur, David

    2009-12-01

    Freehand sketching is widely regarded as an efficient and natural way for interaction between computers and humans. We present a robust computerized scheme to automatically segment freehand sketches into a series of components with specific geometric meaning regardless of whether these are generated online or offline. This task is a necessary first step toward sketch understanding. By exploiting the interpolation / extrapolation characteristic of Radial Basis Functions (RBFs), a greedy algorithm consisting of forward and backward operations is proposed for finding the minimum set of segmentation points that can be used to reconstruct with high fitting accuracy freehand sketches in the form of implicit functions. To obtain segmentation points, a simple angle based rule is used to remove "bridging" points that provide a smooth transition between consecutive sketch components. Feasibility of the proposed algorithm is demonstrated by a preliminary performance assessment study using ten computer generated drawings. These experiments show that in this dataset sensitivity of the segmentation was higher than 97.5% with a false positive (FP) rate of approximately 25%. The majority of false positive identifications are located on arc regions where a larger number of segmentation points are needed for reconstruction purposes. The primary contribution of this algorithm is that it transforms an ambiguous problem namely, freehand sketch segmentation, into an implicit function fitting operation. Therefore, this proposed approach has several advantages including independence of the actual sketching activity, and the ability for a satisfactory detection of the transition point between a line and an arc or between two arcs.

  10. Cilia in vertebrate left-right patterning.

    PubMed

    Dasgupta, Agnik; Amack, Jeffrey D

    2016-12-19

    Understanding how left-right (LR) asymmetry is generated in vertebrate embryos is an important problem in developmental biology. In humans, a failure to align the left and right sides of cardiovascular and/or gastrointestinal systems often results in birth defects. Evidence from patients and animal models has implicated cilia in the process of left-right patterning. Here, we review the proposed functions for cilia in establishing LR asymmetry, which include creating transient leftward fluid flows in an embryonic 'left-right organizer'. These flows direct asymmetric activation of a conserved Nodal (TGFβ) signalling pathway that guides asymmetric morphogenesis of developing organs. We discuss the leading hypotheses for how cilia-generated asymmetric fluid flows are translated into asymmetric molecular signals. We also discuss emerging mechanisms that control the subcellular positioning of cilia and the cellular architecture of the left-right organizer, both of which are critical for effective cilia function during left-right patterning. Finally, using mosaic cell-labelling and time-lapse imaging in the zebrafish embryo, we provide new evidence that precursor cells maintain their relative positions as they give rise to the ciliated left-right organizer. This suggests the possibility that these cells acquire left-right positional information prior to the appearance of cilia.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.

  11. Anarchy, socialism and a Darwinian left.

    PubMed

    Clarke, Ellen

    2006-03-01

    In A Darwinian left Peter Singer aims to reconcile Darwinian theory with left wing politics, using evolutionary game theory and in particular a model proposed by Robert Axelrod, which shows that cooperation can be an evolutionarily successful strategy. In this paper I will show that whilst Axelrod's model can give support to a kind of left wing politics, it is not the kind that Singer himself envisages. In fact, it is shown that there are insurmountable problems for the idea of increasing Axelrodian cooperation within a welfare state. My surprising conclusion will be that a Darwinian left worthy of the name would be anarchistic.

  12. Crustal radial anisotropy beneath Cameroon from ambient noise tomography

    NASA Astrophysics Data System (ADS)

    Ojo, Adebayo Oluwaseun; Ni, Sidao; Li, Zhiwei

    2017-01-01

    To increase the understanding of crustal deformation and crustal flow patterns due to tectonic processes in Cameroon, we study the lateral variability of the crustal isotropic velocity and radial anisotropy estimated using Ambient Noise Tomography (ANT). Rayleigh and Love wave Noise Correlation Functions (NCFs) were retrieved from the cross-correlation of seismic ambient noise data recorded in Cameroon, and phase velocities at periods of 8 to 30 s were measured to perform surface wave tomography. Joint inversion of Rayleigh and Love wave data for isotropic velocity models could not fit the observed dispersions simultaneously. We attribute the Love-Rayleigh discrepancy to the presence of radial anisotropy in the crust and estimated its magnitude. Our 3-D radial anisotropic model reveals the spatial variation of strong to weak positive (Vsh > Vsv) and negative (Vsv > Vsh) radial anisotropy in the crust. We observe negative radial anisotropy in the upper crust that is associated mainly with the location of a previously reported mantle plume. The anisotropy could be attributed to the vertical alignment of fossil microcracks or metamorphic foliations due to the upwelling of plume material. A strong positive radial anisotropy is centered at the location of an inferred boundary between the Congo Craton and the Oubanguides Belt that might be related to the preferred orientation of crustal anisotropic minerals associated with shearing in this fault zone. The middle crust is characterized by a widespread negative radial anisotropy that is likely caused by the flow-induced alignment of anisotropic minerals that crystallized during magma intrusion. The magnitude of the radial anisotropy varies systematically from predominantly negative in the middle crust to positive in the lower crust. The imaged patterns of the isotropic velocity and radial anisotropy are consistent with previous studies and agree with regional tectonics.

  13. Radial intensity projection for lumen: application to CT angiographic imaging

    NASA Astrophysics Data System (ADS)

    Kokubun, Hiroto; Miyazaki, Osamu; Hayashi, Hiromitsu

    2006-03-01

    For the diagnosis of lumen, such as plaque in the coronary and polyp in the colon, it is important to create the cross sectional image of tubular organ on the basis of luminal centerline (i.e., Curved Planar Reformation: CPR). However, since each CPR image has the only limited angle information, it may overlook objects of diagnostic importance. To overcome this limitation and improve diagnostic accuracy we have developed a method called Radial Intensity Projection for lumen (RIP) to create an image based on luminal centerline that integrates all directional information. RIP is executed as follows. At first image processing is performed on array of pixel in the orthogonal direction to a luminal centerline. Secondly, this image processing is performed repeatedly in the angle direction along a luminal centerline. Finally, RIP image, which incorporates all directional information based on luminal centerline, is created. In addition to developing the RIP method for the diagnosis of soft plaque, which is considered as one of the main causes of myocardial infarction, we have also developed the profile step imaging method (PSI). This is an algorithm for visualizing a level gradient point in the radial direction, paying attention to the fact that the gradient approaches zero at the region of soft plaque. We applied RIP method to the clinical image data of a coronary angiography, which has been scanned with the multi slice CT scanner. Using RIP method, it is possible to check the existence of calcified plaque present in the surrounding of a vessel wall without changing the view angle. We have also applied PSI method to the clinical image of a coronary angiography with a soft plaque. The PSI image overlaid on RIP image enables us to verify the high possibility of existing soft plaque. Moreover, the perspectively mapped RIP image to a half pipe object allows us to grasp the orientation of plaque more easily. RIP method is also effective for extended organs, such as peripheral

  14. Analytical design of an advanced radial turbine. [automobile engines

    NASA Technical Reports Server (NTRS)

    Large, G. D.; Finger, D. G.; Linder, C. G.

    1981-01-01

    The aerodynamic and mechanical potential of a single stage ceramic radial inflow turbine was evaluated for a high temperature single stage automotive engine. The aerodynamic analysis utilizes a turbine system optimization technique to evaluate both radial and nonradial rotor blading. Selected turbine rotor configurations were evaluated mechanically with three dimensional finite element techniques. Results indicate that exceptionally high rotor tip speeds (2300 ft/sec) and performance potential are feasible with radial bladed rotors if the projected ceramic material properties are realized. Nonradial rotors reduced tip speed requirements (at constant turbine efficiency) but resulted in a lower cumulative probability of success due to higher blade and disk stresses.

  15. Radial Distributions of Dusty Plasma Parameters in a Glow Discharge

    SciTech Connect

    Fedoseev, A. V.; Sukhinin, G. I.

    2011-11-29

    A self-consistent model for radial distributions of dusty plasma parameters in a DC glow discharge based on the non-local Boltzmann equation for EEDF, the drift-diffusion equation for ions, and the Poisson equation for self-consistent electric field is presented. The results show that for the case of high dust particles density when the recombination of electrons and ions exceeds the ionization near the tube axis, radial electron and ion fluxes change their direction toward the center of the tube, and the radial electric field is reversed.

  16. Radial electric fields in the vicinity of locked magnetic islands

    SciTech Connect

    Nishimura, S.; Itoh, K.; Ida, K.; Yagi, M.; Itoh, S.-I.

    2010-12-15

    The radial electric field in the vicinity of magnetic islands locked by resonant magnetic perturbations (static error fields) is numerically studied using a set of reduced two-fluid equations. The asymmetric radial electric fields across locked magnetic islands are observed, which are due to the symmetry breaking effects such as the cylindrical geometry and inhomogeneous electron diamagnetic drift. It is found that the magnitude of the difference (between maximum and minimum radial electric fields around O-point) is proportional to the averaged electron diamagnetic drift frequency inside magnetic islands and the square of the island width, but inversely proportional to the square root of the ion viscosity.

  17. Single radial immunodiffusion analysis for quantitation of colostral immunoglobulin concentration.

    PubMed

    Fleenor, W A; Stott, G H

    1981-05-01

    Relative accuracy of the single radial immunodiffusion technique to measure immunoglobulin concentrations of colostral preparations (whey, whole, or fat-free) has been assessed. Fresh colostrum samples were analyzed for major constituents. Gammaglobulin as a standard was compared to total immunoglobulin concentration derived from single radial immunodiffusion analysis of colostral preparations with no differences except between standard and whey. Differences were in part from either enhancement or interference of immunoglobulin diffusion by colostral constituents. Removal of casein and fat during whey preparations caused a concentrating effect upon immunoglobulin constituents resulting in exaggerated precipitin rings. Whey has produced unreliable results: therefore, whole colostrum is recommended for single radial immunodiffusion analysis.

  18. A radial basis function Galerkin method for inhomogeneous nonlocal diffusion

    DOE PAGES

    Lehoucq, Richard B.; Rowe, Stephen T.

    2016-02-01

    We introduce a discretization for a nonlocal diffusion problem using a localized basis of radial basis functions. The stiffness matrix entries are assembled by a special quadrature routine unique to the localized basis. Combining the quadrature method with the localized basis produces a well-conditioned, sparse, symmetric positive definite stiffness matrix. We demonstrate that both the continuum and discrete problems are well-posed and present numerical results for the convergence behavior of the radial basis function method. As a result, we explore approximating the solution to anisotropic differential equations by solving anisotropic nonlocal integral equations using the radial basis function method.

  19. Measuring Stellar Radial Velocities with a LISA Spectrograph

    NASA Astrophysics Data System (ADS)

    Boyd, David

    2016-05-01

    Conventional wisdom says it should not be possible to measure stellar radial velocities with a useful degree of precision with a spectrograph having spectral resolution of 1000. This paper will demonstrate that with a combination of careful observational technique and the use of cross correlation it is possible to far exceed initial expectations. This is confirmed by reproducing the known radial velocity of a catalogued SB1 star with a precision of 5.2 km/s. To demonstrate the scientific potential of such a spectrograph, we use radial velocity measurements to confirm the binary nature and measure the orbital period and parameters of a suspected post common envelope binary.

  20. Functional measurements based on feature tracking of cine magnetic resonance images identify left ventricular segments with myocardial scar

    PubMed Central

    2009-01-01

    Background The aim of the study was to perform a feature tracking analysis on cine magnetic resonance (MR) images to elucidate if functional measurements of the motion of the left ventricular wall may detect scar defined with gadolinium enhanced MR. Myocardial contraction can be measured in terms of the velocity, displacement and local deformation (strain) of a particular myocardial segment. Contraction of the myocardial wall will be reduced in the presence of scar and as a consequence of reduced myocardial blood flow. Methods Thirty patients (3 women and 27 men) were selected based on the presence or absence of extensive scar in the anteroseptal area of the left ventricle. The patients were investigated in stable clinical condition, 4-8 weeks post ST-elevation myocardial infarction treated with percutaneous coronary intervention. Seventeen had a scar area >75% in at least one anteroseptal segment (scar) and thirteen had scar area <1% (non-scar). Velocity, displacement and strain were calculated in the longitudinal direction, tangential to the endocardial outline, and in the radial direction, perpendicular to the tangent. Results In the scar patients, segments with scar showed lower functional measurements than remote segments. Radial measurements of velocity, displacement and strain performed better in terms of receiver-operator-characteristic curves (ROC) than the corresponding longitudinal measurements. The best area-under-curve was for radial strain, 0.89, where a cut-off value of 38.8% had 80% sensitivity and 86% specificity for the detection of a segment with scar area >50%. As a percentage of the mean, intraobserver variability was 16-14-26% for radial measurements of displacement-velocity-strain and corresponding interobserver variability was 13-12-18%. Conclusion Feature tracking analysis of cine-MR displays velocity, displacement and strain in the radial and longitudinal direction and may be used for the detection of transmural scar. The accuracy and

  1. Concordance Between BeamF3 and MRI-neuronavigated Target Sites for Repetitive Transcranial Magnetic Stimulation of the Left Dorsolateral Prefrontal Cortex

    PubMed Central

    Mir-Moghtadaei, Arsalan; Caballero, Ruth; Fried, Peter; Fox, Michael D.; Lee, Katherine; Giacobbe, Peter; Daskalakis, Zafiris J.; Blumberger, Daniel M.; Downar, Jonathan

    2016-01-01

    Background The dorsolateral prefrontal cortex (DLPFC) is a common target for repetitive transcranial magnetic stimulation (rTMS) in major depression, but the conventional “5 cm rule” misses DLPFC in > 1/3 cases. Another heuristic, BeamF3, locates the F3 EEG site from scalp measurements. MRI-guided neuronavigation is more onerous, but can target a specific DLPFC stereotaxic coordinate directly. The concordance between these two approaches has not previously been assessed. Objective To quantify the discrepancy in scalp site between BeamF3 versus MRI-guided neuronavigation for left DLPFC. Methods Using 100 pre-treatment MRIs from subjects undergoing left DLPFC-rTMS, we localized the scalp site at minimum Euclidean distance from a target MNI coordinate (X − 38 Y + 44 Z + 26) derived from our previous work. We performed nasion-inion, tragus–tragus, and head-circumference measurements on the same subjects’ MRIs, and applied the BeamF3 heuristic. We then compared the distance between BeamF3 and MRI-guided scalp sites. Results BeamF3-to-MRI-guided discrepancies were <0.65 cm in 50% of subjects, <0.99 cm in 75% of subjects, and <1.36 cm in 95% of subjects. The angle from midline to the scalp site did not differ significantly using MRI-guided versus BeamF3 methods. However, the length of the radial arc from vertex to target site was slightly but significantly longer (mean 0.35 cm) with MRI-guidance versus BeamF3. Conclusions The BeamF3 heuristic may provide a reasonable approximation to MRI-guided neuronavigation for locating left DLPFC in a majority of subjects. A minor optimization of the heuristic may yield additional concordance. PMID:26115776

  2. The Axisymmetric Analysis of Circular Plates Using the Radial Point Interpolation Method

    NASA Astrophysics Data System (ADS)

    Vasheghani Farahani, Behzad; Berardo, José Manuel; Drgas, Rafal; César de Sá, José M. A.; Ferreira, António J. M.; Belinha, Jorge

    2015-11-01

    This work extends the radial point interpolation method (RPIM) to the elasto-static analysis of circular plates. Instead using a plate bending theory, the 2D axisymmetric deformation theory is assumed. The RPIM enforces the nodal connectivity with the influence-domain concept and integrates numerically the integro-differential equations governing the studied phenomenon using a background integration mesh. Thus, both concepts are revised and more adequate parameters are found for the axisymmetric RPIM approach. Several benchmark circular plate examples are solved and the results are compared with other numerical approaches, showing that the RPIM is capable to obtain accurate and smooth variable fields.

  3. Radial basis function interpolation in the limit of increasingly flat basis functions

    NASA Astrophysics Data System (ADS)

    Kindelan, Manuel; Moscoso, Miguel; González-Rodríguez, Pedro

    2016-02-01

    We propose a new approach to study Radial Basis Function (RBF) interpolation in the limit of increasingly flat functions. The new approach is based on the semi-analytical computation of the Laurent series of the inverse of the RBF interpolation matrix described in a previous paper [3]. Once the Laurent series is obtained, it can be used to compute the limiting polynomial interpolant, the optimal shape parameter of the RBFs used for interpolation, and the weights of RBF finite difference formulas, among other things.

  4. One School's Approach to No Child Left Behind

    ERIC Educational Resources Information Center

    Shibley, Ivan A.

    2005-01-01

    The NO VACANCY sign has been hanging out at the Columbia-Montour Area Vocational-Technical School (CMAVTS) for the past several years. A variety of reasons may have contributed to the building being at full capacity. A new administrative director, Steve Walk, was hired in 1999 to change the image of the school. Since his arrival, High Schools That…

  5. Hemodynamic forces in a model left ventricle

    NASA Astrophysics Data System (ADS)

    Domenichini, Federico; Pedrizzetti, Gianni

    2016-12-01

    Intraventricular pressure gradients were clinically demonstrated to represent one useful indicator of the left ventricle (LV) function during the development of heart failure. We analyze the fluid dynamics inside a model LV to improve the understanding of the development of hemodynamic forces (i.e., mean pressure gradient) in normal conditions and their modification in the presence of alterations of LV tissue motion. To this aim, the problem is solved numerically and the global force exchanged between blood flow and LV boundaries is computed by volume integration. We also introduce a simplified analytical model, based on global conservation laws, to estimate hemodynamic forces from the knowledge of LV tissue information commonly available in cardiac imaging. Numerical results show that the normal intraventricular gradients feature a deep brief suction at early diastolic filling and a persistent thrust during systolic ejection. In presence of abnormalities of the wall motion, the loss of time synchrony is more relevant than the loss of spatial uniformity in modifying the normal pressure gradient spatiotemporal pattern. The main findings are reproduced in the integral model, which represents a possible easy approach for integrating fluid dynamics evaluations in the clinical examination.

  6. The M 4 Core Project with HST - IV. Internal kinematics from accurate radial velocities of 2771 cluster members★

    NASA Astrophysics Data System (ADS)

    Malavolta, L.; Piotto, G.; Bedin, L. R.; Sneden, C.; Nascimbeni, V.; Sommariva, V.

    2015-12-01

    We present a detailed study of the internal kinematics of the Galactic globular cluster M 4 (NGC 6121), by deriving the radial velocities from 7250 spectra for 2771 stars distributed from the upper part of the red giant branch down to the main sequence. We describe new approaches to determine the wavelength solution from day-time calibrations and to determine the radial velocity drifts that can occur between calibration and science observations when observing with the GIRAFFE spectrograph at Very Large Telescope. Two techniques to determine the radial velocity are compared, after a qualitative description of their advantages with respect to other commonly used algorithm, and a new approach to remove the sky contribution from the spectra obtained with fibre-fed spectrograph and further improve the radial velocity precision is presented. The average radial velocity of the cluster is = 71.08 ± 0.08 km s-1 with an average dispersion of μ _{v_c} = 3.97 km s-1. Using the same data set and the same statistical approach of previous analyses, 20 additional binary candidates are found, for a total of 87 candidates. A new determination of the internal radial velocity dispersion as a function of cluster distance is presented, resulting in a dispersion of 4.5 km s-1 within 2 arcmin from the centre of cluster and steadily decreasing outward. We statistically confirm the small amplitude of the cluster rotation, as suggested in the past by several authors. This new analysis represents a significant improvement with respect to previous results in literature and provides a fundamental observational input for the modelling of the cluster dynamics.

  7. Radial Anisotropy in the Lithosphere and Asthenosphere Beneath the Northeastern Tibetan Plateau from Surface Wave Tomography

    NASA Astrophysics Data System (ADS)

    Akanbi, O. E.; Li, A.; Li, L.; Murphy, M. A.

    2015-12-01

    We analyzed Rayleigh and Love wave data from distant earthquakes recorded by 36 broadband stations that were operated in two years in the NE Tibetan Plateau. Phase velocity variations were determined in a period range of 20 to 91 s for Love wave and 20 to 100 s for Rayleigh wave using a two-plane-wave method, which can accounts for non-planar energy in the incoming wave field caused by structures outside the study area. 3-D shear wave velocity and radial anisotropy models were constructed from the obtained Rayleigh and Love wave dispersions. The mid-lower crust is characterized by strong positive anisotropy (VSH>VSV) beneath the Qilian-Qinling Orogen and relative weak radial anisotropy beneath the Kunlun Mountains. The mantle above 90 km is largely isotropic while positive anisotropy increases gradually with depth below 90 km, which probably marks the lithosphere-asthenosphere boundary (LAB). In contrast, shear wave velocity does not show an obvious reduction at 90 km and fails to detect the LAB. A low shear wave velocity anomaly and relatively negative radial anisotropy are imaged in the entire lithosphere under the Kunlun restraining bend, indicating a weak lithosphere under compressional deformation. The asthenosphere here is characterized by significantly lower velocity and stronger positive anisotropy than the surrounding region, suggesting a warmer and weaker asthenosphere block. Our observations are consistent with a geologic model in which the lithosphere under the restraining bend was thickened and subsequently delaminated, and the warm asthenosphere then filled up the space left by the delamination.

  8. Near-unity broadband absorption designs for semiconducting nanowire arrays via localized radial mode excitation.

    PubMed

    Fountaine, Katherine T; Kendall, Christian G; Atwater, Harry A

    2014-05-05

    We report design methods for achieving near-unity broadband light absorption in sparse nanowire arrays, illustrated by results for visible absorption in GaAs nanowires on Si substrates. Sparse (<5% fill fraction) nanowire arrays achieve near unity absorption at wire resonant wavelengths due to coupling into 'leaky' radial waveguide modes of individual wires and wire-wire scattering processes. From a detailed conceptual development of radial mode resonant absorption, we demonstrate two specific geometric design approaches to achieve near unity broadband light absorption in sparse nanowire arrays: (i) introducing multiple wire radii within a small unit cell array to increase the number of resonant wavelengths, yielding a 15% absorption enhancement relative to a uniform nanowire array and (ii) tapering of nanowires to introduce a continuum of diameters and thus resonant wavelengths excited within a single wire, yielding an 18% absorption enhancement over a uniform nanowire array.

  9. Transient, radial temperature distribution in a porous medium during fluid injection

    SciTech Connect

    Dunn, J.C.; Nilson, R.H.

    1982-01-01

    Analytical and numerical solutions are presented for the transient, radial temperature distribution in a porous medium which is subjected to a constant-rate injection of an incompressible fluid from a wellbore. The formulation includes energy transfer by conduction and convection, and the Danckwerts boundary condition is applied at the finite-radius wellbore. At late times, the numerical solutions approach a self-similar form which can be described in terms of the incomplete Gamma function. In typical petroleum and geothermal applications, convergence to the asymptotic similarity solutions occurs on a time scale of roughly one hour. The results are generally applicable to a broad range of convection-diffusion phenomena which are best described in radial coordinates.

  10. Percutaneous Coronary Intervention in Single Coronary Artery from Right Sinus: Radial Route is Right

    PubMed Central

    Mahla, Rakesh; Mahla, Himanshu; Choudhary, Dinesh; Nahata, Pintu

    2015-01-01

    We present percutaneous coronary intervention (PCI) using radial approach in a rare case of single coronary artery originating from the right sinus. Although these anomalies and stenosis of anomalous vessels have been described previously, treatment of atherosclerotic lesions by PCI has rarely been reported. There is a definite procedural risk during PCI in patients with a single ostium because dissection with the guiding catheter would result in a catastrophic event. Additionally, technical difficulties may occur due to the ostial configuration and course of the branch to be stented. The patient suffered an acute coronary syndrome-inferior wall STEMI, and was thrombolysed elsewhere within a window period of 4 h. He had post myocardial infarction (MI) angina and was referred to our center after 3 days of thrombolysis. We present this technically challenging and rare case in which PCI of right coronary artery was performed through the radial route. PMID:26713181

  11. Narrow-angle tail radio sources and evidence for radial orbits in Abell clusters

    NASA Technical Reports Server (NTRS)

    O'Dea, Christopher P.; Owen, Frazer N.; Sarazin, Craig L.

    1986-01-01

    Published observational data on the tail orientations (TOs) of 60 narrow-angle-tail (NAT) radio sources in Abell clusters of galaxies are analyzed statistically using a maximum-likelihood approach. The results are presented in a table, and it is found that the observed TO distributions in the whole sample and in subsamples of morphologically regular NATs and NATs with pericentric distances d greater than 500 kpc are consistent with isotropic orbits, whereas the TOs for NATs with d less than 500 kpc are consistent with highly radial orbits. If radial orbits were observed near the centers of other types of cluster galaxies as well, it could be inferred that violent relaxation during cluster formation was incomplete, and that clusters form by spherical collapse and secondary infall, as proposed by Gunn (1977).

  12. Simultaneous generation and focus of radially polarized light with metal-dielectric grating metasurface

    NASA Astrophysics Data System (ADS)

    Luo, Jun; Zhang, Zuojun; Song, Maowen; He, Anguo; Yu, Honglin

    2017-01-01

    Simultaneous manipulation of light polarization and phase possesses great significance for modern optical technologies. Here we propose metal-dielectric gratings capable of tailoring the polarization and phase of light based on polarization filtering with the polarization extinction ratio exceeding 10 dB and the transmittance higher than 65%. The standard radially polarized (RP) light with axially symmetric polarization distribution can be generated by using arrayed grating with gradient phase under the illumination of circularly polarized (CP) light. Besides, a RP metasurface lens with high numerical aperture is presented, which can convert the CP light into the focused radially polarized light at wavelength of 632.8 nm. This compact and efficient approach would have potential applications in beam manipulation, super-resolution imaging and integrated optics system.

  13. Feasibility of radial and circumferential strain analysis using 2D speckle tracking echocardiography in cats

    PubMed Central

    TAKANO, Hiroshi; ISOGAI, Tomomi; AOKI, Takuma; WAKAO, Yoshito; FUJII, Yoko

    2014-01-01

    The purpose of the present study is to investigate the feasibility of strain analysis using speckle tracking echocardiography (STE) in cats and to evaluate STE variables in cats with hypertrophic cardiomyopathy (HCM). Sixteen clinically healthy cats and 17 cats with HCM were used. Radial and circumferential strain and strain rate variables in healthy cats were measured using STE to assess the feasibility. Comparisons of global strain and strain variables between healthy cats and cats with HCM were performed. Segmental assessments of left ventricle (LV) wall for strain and strain rate variables in cats with HCM were also performed. As a result, technically adequate images were obtained in 97.6% of the segments for STE analysis. Sedation using buprenorphine and acepromazine did not affect any global strain nor strain rate variable. In LV segments of cats with HCM, reduced segmental radial strain and strain rate variables had significantly related with segmental LV hypertrophy. It is concluded that STE analysis using short axis images of LV appeared to be clinically feasible in cats, having the possibility to be useful for detecting myocardial dysfunctions in cats with diseased heart. PMID:25373881

  14. Feasibility of radial and circumferential strain analysis using 2D speckle tracking echocardiography in cats.

    PubMed

    Takano, Hiroshi; Isogai, Tomomi; Aoki, Takuma; Wakao, Yoshito; Fujii, Yoko

    2015-02-01

    The purpose of the present study is to investigate the feasibility of strain analysis using speckle tracking echocardiography (STE) in cats and to evaluate STE variables in cats with hypertrophic cardiomyopathy (HCM). Sixteen clinically healthy cats and 17 cats with HCM were used. Radial and circumferential strain and strain rate variables in healthy cats were measured using STE to assess the feasibility. Comparisons of global strain and strain variables between healthy cats and cats with HCM were performed. Segmental assessments of left ventricle (LV) wall for strain and strain rate variables in cats with HCM were also performed. As a result, technically adequate images were obtained in 97.6% of the segments for STE analysis. Sedation using buprenorphine and acepromazine did not affect any global strain nor strain rate variable. In LV segments of cats with HCM, reduced segmental radial strain and strain rate variables had significantly related with segmental LV hypertrophy. It is concluded that STE analysis using short axis images of LV appeared to be clinically feasible in cats, having the possibility to be useful for detecting myocardial dysfunctions in cats with diseased heart.

  15. [Left ventricular function in pulmonary arterial hypertension].

    PubMed

    Khomaziuk, V A

    1998-12-01

    Echocardiographic evaluation was done of left ventricular functional state in 90 patients with primary and secondary pulmonary arterial hypertension with and without intercavitary shunting. Changes in left ventricular function were identified in 86% cases; they reflected disturbances in both ventricles compensatory interaction. The degree of changes depended on the degree of dilatation of the right ventricle and level of interchamber shunting.

  16. Spinal cord ischemia and left atrial myxoma.

    PubMed

    Hirose, G; Kosoegawa, H; Takado, M; Shimazaki, K; Murakami, E

    1979-07-01

    A 62-year-old man had an acute, transient, flaccid paraplegia. Examination showed a primary cardiac tumor with emboli to major branches of the aorta. A myxoma was removed from the left atrium, and normal function returned. Left atrial myxoma should be suspected as a cause for embolism to the CNS.

  17. Two Rare Variants of Left Vertebral Artery.

    PubMed

    Singh, Rajani

    2017-02-15

    Though the variations of vertebral artery are clinically asymptomatic yet abnormalities are of diagnostic importance either prior to vascular surgery in the neck region or in patients of intravascular diseases such as arteriovenous malformations or cerebral aneurysms. Therefore, the aim of the study is to bring out 2 variations in the configuration of vertebral artery and their clinical implication. During dissection of thorax of 2 female cadavers, 2 different variants of configurations of left vertebral arteries were observed. In 1 patient, the left vertebral artery arose aberrantly from arch of aorta between left common carotid artery and left subclavian artery. This artery then, following oblique course, abnormally entered into foramen transversarium of C4 vertebra. In the second patient, the left common stump emerged from arch of aorta in the left side of left common carotid artery and then instantly bifurcated into vertebral artery and subclavian artery. Then following the usual oblique course, the left vertebral artery anomalously entered into foramen transversarium of C3 vertebra at the level of upper border of thyroid cartilage. The knowledge of these rare variations in the origin of vertebral artery is of paramount importance to surgeons performing surgery in neck region, radiologist performing angiography to avoid misinterpretation of radiographs and to anatomists for rare variations in academics and research.

  18. Social Studies. Political Theory: Left to Right.

    ERIC Educational Resources Information Center

    Heggy, Joan

    The course outlined in this guide offers an in-depth look at the political left and right, including characteristics held by the extreme left and right, related social and economic theories, and the differences between theory and practice. The students will read and discuss viewpoints illustrative of a cross section of ideological positions and…

  19. A Conversation about No Child Left Behind

    ERIC Educational Resources Information Center

    Taylor, Brian

    2007-01-01

    This article presents an interview with J. Michael Ortiz, a member of the Aspen Institute's Commission on No Child Left Behind, on the issues concerning the No Child Left Behind Act (NCLB). Aspen Institute's Commission is an independent panel that was established in 2006 to conduct a high-level review of the federal government's signature…

  20. Time Components of the Left Ventricle.

    ERIC Educational Resources Information Center

    Franks, B. Don

    The purpose of this study was to examine the relationship of the time components of the left ventricle. Since one of the ways to investigate cardiac function is to analyze the time intervals between particular events of the cardiac cycle, various time intervals of systole and diastole of the left ventricle were measured from simultaneous…

  1. Pure Left Neglect for Arabic Numerals

    ERIC Educational Resources Information Center

    Priftis, Konstantinos; Albanese, Silvia; Meneghello, Francesca; Pitteri, Marco

    2013-01-01

    Arabic numerals are diffused and language-free representations of number magnitude. To be effectively processed, the digits composing Arabic numerals must be spatially arranged along a left-to-right axis. We studied one patient (AK) to show that left neglect, after right hemisphere damage, can selectively impair the computation of the spatial…

  2. Temporal Changes in Left Ventricular Mechanics: Impact of Bed Rest and Exercise

    NASA Technical Reports Server (NTRS)

    Scott, Jessica M.; Matz, Timothy; Caine, Timothy; Martin, David S.; Downs, Meghan; Ploutz-Snyder, Lori

    2014-01-01

    BACKGROUND Current techniques used to assess cardiac function following spaceflight or head-down tilt bed rest (HDTBR) involve invasive and time consuming procedures such as Swan-Ganz catheterization or cardiac magnetic resonance imaging. An alternative approach, echocardiography, can monitor cardiac morphology and function via sequential measurements of left ventricular (LV) mass and ejection fraction (EF). However, LV mass and EF are insensitive measures of early (subclinical) cardiac deconditioning, and a decrease in LV mass and EF become evident only once significant deconditioning has already occurred. The use of more sensitive and specific echocardiographic techniques such as speckle tracking imaging may address the current limitations of conventional cardiac imaging techniques to provide insight into the magnitude and time course of cardiac deconditioning. METHODS Speckle tracking assessment of longitudinal, radial, and circumferential strain and twist was used to evaluate the impact of 70 days of HDTBR (n=7) and HDTBR + exercise (n=11) on temporal changes in LV mechanics. Echocardiograms were performed pre (BR-2), during (BR31, 70), and following (BR+4hr) HDTBR. Multi-level modeling was used to evaluate the effect of HDTBR condition (Control, Exercise) on cardiac variables. RESULTS Compared to BR-2, longitudinal (BR-2: - 19.0 +/- 1.8%; BR31: -15.9 +/- 2.4%; BR70: -14.9 +/- 2.4%; BR+4hr: -16.0 +/- 2.1%) and radial (BR-2: 15.0 +/- 1.9%; BR31: 12.3 +/- 2.4%; BR70: 11.3 +/- 2.2%; BR+4hr: 13.5 +/- 2.5% ) strains were significantly impaired during and following bed rest (p<0.05), while twist (BR-2: 18.0 +/- 4.0deg; BR31: 18.1 +/- 3.8deg; BR70: 17.0 +/- 3.6deg; BR+4hr:18.1 +/- 4.3deg) was significantly decreased at BR70 (p<0.05). In contrast, exercise preserved LV mechanics for longitudinal strain (BR-2: -19.1 +/- 1.5%; BR 31: -19.0 +/- 2.4%; BR70: -19.1 +/- 2.7%; BR+4hr: -17.8 +/- 2.1%), radial strain (BR-2: 13.8 +/- 2.4; BR31: 14.7 +/- 2.4; BR70: 14.4 +/- 1

  3. Off-pump revascularization for significant left ventricular dysfunction.

    PubMed

    Woo, Y Joseph; Grand, Todd J; Liao, George P; Panlilio, Corinna M

    2006-08-01

    Left ventricular dysfunction is a predictor of perioperative morbidity and mortality in on-pump coronary artery bypass grafting. Obligatory global myocardial ischemia and injury induced during crossclamping as well as adverse systemic effects of cardiopulmonary bypass may induce a disproportionately greater overall physiologic insult in patients with poor ventricular function. All patients undergoing nonemergency off-pump coronary artery bypass by a single surgeon during an 18-month period were retrospectively analyzed. Two groups with preoperative ejection fraction classified as poor (10%-35%; n = 31) or normal (55%-80%; n = 60) were compared. The mean ejection fractions were 26% +/- 1% and 63% +/- 1% respectively, p < 0.000001. In those with significant left ventricular dysfunction, there were 2.8 +/- 0.1 grafts per patient, time to extubation was 8.4 +/- 1.2 hours, and discharge was after 4.9 +/- 0.6 days. These results were statistically equivalent to those in the group with normal left ventricular function. There was no intraaortic balloon pump insertion or mortality in either group. This technique provides an effective means of safely revascularizing patients with significant left ventricular dysfunction, and it may provide a valuable alternative approach in patients with ischemic cardiomyopathy.

  4. Radial Distribution of Electron Spectra from High-Energy Ions

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Katz, Robert; Wilson, John W.

    1998-01-01

    The average track model describes the response of physical and biological systems using radial dose distribution as the key physical descriptor. We report on an extension of this model to describe the average distribution of electron spectra as a function of radial distance from an ion. We present calculations of these spectra for ions of identical linear energy transfer (LET), but dissimilar charge and velocity to evaluate the differences in electron spectra from these ions. To illustrate the usefulness of the radial electron spectra for describing effects that are not described by electron dose, we consider the evaluation of the indirect events in microdosimetric distributions for ions. We show that folding our average electron spectra model with experimentally determined frequency distributions for photons or electrons provides a good representation of radial event spectra from high-energy ions in 0.5-2 micrometer sites.

  5. Holographic analogy of the spatial radial carrier analysis of interferograms

    NASA Astrophysics Data System (ADS)

    Garcia-Marquez, Jorge L.; Malacara-Hernandez, Daniel

    1996-07-01

    A holographic analogy ofthe analysis of thterferograms with a spatial radial carrier introduced by means of defocusing and its practical applications is describei Special emphasis is made ofthe conditions imposed on the Fourier spectra ofthe interferogram.

  6. Osteocutaneous radial forearm free flap in subtotal nasal reconstruction

    PubMed Central

    Moore, Alexander Michael; Montgomery, Jenny; McMahon, Jeremy; Sheikh, Saghir

    2014-01-01

    A 66-year-old man presented with a large squamous cell carcinoma of the right nasal vestibule. He underwent partial rhinectomy and medial maxillectomy followed by staged reconstruction. Reconstruction of a full-thickness nasal defect requires repair of three distinct layers: the skin–soft tissue envelope, subsurface framework and intranasal lining. We report the first use in the UK of an osteocutaneous radial forearm free flap in the reconstruction of a subtotal nasal deficit. The skin of the radial forearm free flap was tubed to recreate the nasal lining and the radial bone reconstructed the dorsal contour of the nose. A full-thickness paramedian forehead flap supplied external coverage. The osteocutaneous radial forearm free flap and forehead flap is a viable option for large nasal defects requiring reconstruction of framework, nasal lining and external covering. PMID:25427933

  7. INTERIOR VIEW WITH CARLTON RADIAL ARM DRILL PRESS (THE CARLTON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH CARLTON RADIAL ARM DRILL PRESS (THE CARLTON MACHINE TOOL CO., CINCINNATI, OHIO) WITH MACHINE OPERATOR, EDDIE BURTTRAM. - O'Neal Steel, Incorporated, Fabrication Shop, 744 Forty-first Avenue North, Birmingham, Jefferson County, AL

  8. 13. RADIAL DRILL, ENGINE LATHE, DRILL PRESS, AND GRINDER (L ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. RADIAL DRILL, ENGINE LATHE, DRILL PRESS, AND GRINDER (L TO R)-LOOKING SOUTHEAST. - W. A. Young & Sons Foundry & Machine Shop, On Water Street along Monongahela River, Rices Landing, Greene County, PA

  9. General and specific perceptual learning in radial speed discrimination.

    PubMed

    Huang, Xuan; Lu, Hongjing; Zhou, Yifeng; Liu, Zili

    2011-04-14

    The specificity of learning in speed discrimination was examined in three psychophysical experiments. In Experiment 1, half of the observers trained with inward motion direction on a speed discrimination task, whereas the other half trained on the same task but with outward motion direction. The results indicated that significant training-based improvement transferred from a trained radial direction to an untrained radial direction. Experiment 2 confirmed this transfer by showing that complete transfer was obtained even when stimuli moving in an untrained radial direction were used in the transfer task. In Experiment 3, observers were trained at a viewing distance of 114 cm. The results showed that learning transferred partly to the viewing distances of 57 cm and 228 cm. In summary, the present transfer results indicate that reliable generalizations can be obtained in perceptual learning of radial speed discrimination.

  10. Linear radial Regge trajectories for mesons with any quark flavor

    NASA Astrophysics Data System (ADS)

    Afonin, Sergey; Pusenkov, Ilya

    2016-10-01

    In the Regge phenomenology, the radial spectrum of light mesons is given by a linear relation M2n = a(n + b), where a is a universal slope, the dimensionless intercept b depends on quantum numbers, and n enumerates the excited states in radial recurrences. The usual extensions of this relation to heavy quarkonia in the framework of hadron string models typically lead to strong nonlinearities which seem to be at variance with the available experimental data. Introducing a radially static string picture of mesons, we put forward a linear generalization (Mn - m1 - m2)2 = a(n + b), where m1,2 are quark masses. The vector channel contains enough experimental states to check this new relation and a good agreement is observed. It is shown that this generalization leads to a simple estimate of current quark masses from the radial spectra.

  11. Radial inflow gas turbine engine with advanced transition duct

    DOEpatents

    Wiebe, David J

    2015-03-17

    A gas turbine engine (10), including: a turbine having radial inflow impellor blades (38); and an array of advanced transition combustor assemblies arranged circumferentially about the radial inflow impellor blades (38) and having inner surfaces (34) that are adjacent to combustion gases (40). The inner surfaces (34) of the array are configured to accelerate and orient, for delivery directly onto the radial inflow impellor blades (38), a plurality of discrete flows of the combustion gases (40). The array inner surfaces (34) define respective combustion gas flow axes (20). Each combustion gas flow axis (20) is straight from a point of ignition until no longer bound by the array inner surfaces (34), and each combustion gas flow axis (20) intersects a unique location on a circumference defined by a sweep of the radial inflow impellor blades (38).

  12. Radial Fourier multipliers of Lp(R2)

    PubMed Central

    Carbery, Anthony; Gasper, George; Trebels, Walter

    1984-01-01

    We give sufficient conditions (in terms of differentiability and growth properties) for a radial function to be an Lp(R2) Fourier multiplier. These conditions are in the nature of best possible. PMID:16593468

  13. Partial left pericardial defect with herniation of the left atrial appendage

    PubMed Central

    Pernot, C.; Hoeffel, J C.; Henry, M.; Frisch, R.; Brauer, B.

    1972-01-01

    A case is reported of herniation of the left atrial appendage through a partial pericardial defect, probably congenital. The diagnosis was suggested by the history of chest pain and bulging of the middle segment of the left heart border on the plain chest film, without other signs. Angiography revealed a dilated left atrial appendage. An artificial left pneumothorax confirmed the presence of a pleuropericardial defect. The surgical procedure included excision of the appendage and closure of the defect. Images PMID:5034603

  14. Animal trials of a Magnetically Levitated Left-Ventricular Assist Device

    NASA Technical Reports Server (NTRS)

    Paden, Brad; Antaki, James; Groom, Nelson

    2000-01-01

    The University of Pittsburgh/Magnetic Moments mag-lev left-ventricular assist devices (LVADs), the Streamliner HG3b and HG3c, have successfully been implanted in calves. The first was implanted for 4 hours on July 10, 1998 and the second for 34 days on August 24, 1999 respectively. The tests confirmed the feasibility of low power levitation (1.5 watts coil power) and very low blood damage in a mag-lev ventricular assist device. In this paper, we describe the unique geometry of this pump and its design. Key features of this LVAD concept are the passive radial suspension and active voice-coil thrust bearing.

  15. Two scenarios of the radial orbit instability in spherically symmetric collisionless stellar systems

    NASA Astrophysics Data System (ADS)

    Polyachenko, V. L.; Polyachenko, E. V.; Shukhman, I. G.

    2015-01-01

    The stability of a two-parameter family of radially anisotropic models with a nonsingular central density distribution is considered. Instability takes place at a sufficiently strong radial anisotropy (the so-called radial orbit instability, ROI). We show that the character of instability depends not only on the anisotropy but also on the energy distribution of stars. If this distribution is such that the highly eccentric orbits responsible for the instability are "trapped" in the radial direction near the center, then the instability develops with a characteristic growth time that exceeds considerably the Jeans and dynamical times of the trapped particles. In this case, the instability takes place only for even spherical harmonics and is aperiodic. If, however, almost all of the elongated orbits reach the outer radius of the sphere, then both even and odd harmonics turn out to be unstable. The unstable modes corresponding to odd harmonics are oscillatory in nature with characteristic frequencies of the order of the dynamical ones. The unstable perturbations corresponding to even harmonics contain only one aperiodic mode and several oscillatory modes, with the aperiodic mode being always the most unstable one. Two main interpretations of the ROI available in the literature have been analyzed: the "classical" Jeans instability related to an insufficient stellar velocity dispersion in the transversal direction and the "orbital" approach relying heavily on the analogous Lynden-Bell bar formation mechanism in disk galaxies. The assumptions that the perturbations are slow (compared to the orbital frequency of stars) and that the shape of the perturbed potential is symmetric are inherent integral conditions for the applicability of the latter. Our solutions show that the orbital approach cannot be considered as a universal one.

  16. Radial evolution of the energy density of solar wind fluctuations

    NASA Technical Reports Server (NTRS)

    Zank, G. P.; Matthaeus, W. H.; Smith, C. W.

    1995-01-01

    On the basis of transport theories appropriate to a radially expanding solar wind, we describe new results for the radial evolution of the energy density in solar wind fluctuations at MHD scales. These models include the effects of 'mixing' and driving as well as the possibility of non-isotropic MHD turbulence. Implications of these results for solar wind heating, cosmic ray diffusion and interstellar pick-up ions will also be addressed.

  17. Consistency check for radial distribution functions of water

    NASA Astrophysics Data System (ADS)

    Lie, George C.

    1986-12-01

    From a relation between the thermal compressibility and radial distribution function, it is shown that the accuracy of the generally accepted Narten and Levy's experimental radial distribution functions (RDFs) for water is very low, compared with newer experimental results. The most recent experimental RDFs obtained by Soper and Phillips not only pass the consistency check derived, but also have the best overall agreement with the simulated results of Lie and Clementi.

  18. Radial Eigenmodes for a Toroidal Waveguide with Rectangular Cross Section

    SciTech Connect

    Rui Li

    2012-07-01

    In applying mode expansion to solve the CSR impedance for a section of toroidal vacuum chamber with rectangular cross section, we identify the eigenvalue problem for the radial eigenmodes which is different from that for cylindrical structures. In this paper, we present the general expressions of the radial eigenmodes, and discuss the properties of the eigenvalues on the basis of the Sturm-Liouville theory.

  19. Radial basis function neural networks applied to NASA SSME data

    NASA Technical Reports Server (NTRS)

    Wheeler, Kevin R.; Dhawan, Atam P.

    1993-01-01

    This paper presents a brief report on the application of Radial Basis Function Neural Networks (RBFNN) to the prediction of sensor values for fault detection and diagnosis of the Space Shuttle's Main Engines (SSME). The location of the Radial Basis Function (RBF) node centers was determined with a K-means clustering algorithm. A neighborhood operation about these center points was used to determine the variances of the individual processing notes.

  20. Radial Velocities and Binarity of Southern SIM Grid Stars

    DTIC Science & Technology

    2015-01-01

    MNRAS 446, 2055–2058 (2015) doi:10.1093/mnras/stu2239 Radial velocities and binarity of southern SIM grid stars Valeri V. Makarov1‹ and Stephen C...ABSTRACT We present analysis of precision radial velocities (RV) of 1134 mostly red giant stars in the southern sky, selected as candidate astrometric...grid objects for the Space Interferometry Mis- sion (SIM). Only a few (typically, two or three) spectroscopic observations per star have been collected

  1. Investigation of a Photoconductively Switched, Radial Transmission Line Accelerator

    DTIC Science & Technology

    1987-06-01

    that is due to insulator surface flashover in a vacuum. The radial line conductors can be oriented vertically and the structural supports and...possible voltage or electric field pulse to the acceleration gap. Presently, flashover of the vacuum side of the insulator separating the power system...supported by material surfaces . The photoconductively switched radial line accelerator power system is comparable to the -wake field- accelerator

  2. Bilateral radial hemimelia and multiple malformations in a kitten.

    PubMed

    Pisoni, Luciano; Cinti, Filippo; Del Magno, Sara; Joechler, Monika

    2012-08-01

    Hemimelia is a congenital disease of complete or partial absence of one or more bones. The most important hypothesis is that radial agenesis is a consequence of neural crest injury. Treatment selection depends on the degree of the deformity and the reduction of limb function. This report describes a case of bilateral radial hemimelia and multiple malformations in a kitten aged 2 months treated conservatively with splint bandage, until bone maturity. The re-evaluation was performed 4 years later.

  3. TMS over the Left Angular Gyrus Impairs the Ability to Discriminate Left from Right

    ERIC Educational Resources Information Center

    Hirnstein, Marco; Bayer, Ulrike; Ellison, Amanda; Hausmann, Markus

    2011-01-01

    The underlying cognitive and neural mechanisms of the ability to discriminate left from right are hardly explored. Clinical studies from patients with impairments of left-right discrimination (LRD) and neuroimaging data suggest that the left angular gyrus is particularly involved in LRD. Moreover, it is argued that the often reported sex…

  4. On radial heliospheric magnetic fields: Voyager 2 observation and model

    NASA Astrophysics Data System (ADS)

    Wang, C.; Richardson, J. D.; Burlaga, L. F.; Ness, N. F.

    2003-05-01

    The heliospheric magnetic field (HMF) direction, on average, conforms well to the Parker spiral. However, numerous examples of events where the HMF is oriented in near-radial directions for many hours have been reported on the basis of observations inside 5 AU from spacecraft such as ISEE-3 and Ulysses. The magnetic field data observed by Voyager 2 from launch in 1977 through the end of 1982 (i.e., between 1 and ˜10 AU) were searched for all instances of radial fields with durations of 6 hours or more. Radial fields of significant durations at large distances are unusual as the Parker spiral is very tightly wound. The radial HMF events in the inner heliosphere typically occur at times when the solar wind speed is declining gradually, while they tend to be associated with steady wind speeds at distances beyond ˜6 AU. The durations of these events appear to be independent of distance and solar cycle, with an average duration of ˜11 hours. They generally are not associated with interplanetary coronal mass ejections (ICMEs). Possible generation mechanisms of the radial field events related to speed variations near the Sun are investigated by use of a MHD model. We find that a noticeable low-speed plateau of limited duration in solar wind speed near the Sun can produce radial field events having durations of the order of 10 hours in the heliosphere as observed by Voyager 2.

  5. Precise Radial Velocity First Light Observations With iSHELL

    NASA Astrophysics Data System (ADS)

    Cale, Bryson Lee; Plavchan, Peter; Nishimoto, America; Tanner, Angelle M.; Gagne, Jonathan; Gao, Peter; Furlan, Elise; White, Russel J.; Walp, Bernie; von Braun, Kaspar; Brinkworth, Carolyn; Johnson, John A.; Anglada-Escudé, Guillem; Henry, Todd J.; Catanzarite, Joseph; Kane, Stephen R.; Beichman, Charles; Ciardi, David R.; Wallace, J. Kent; Mennesson, Bertrand; Vasisht, Gautam

    2017-01-01

    We present our first light observations with the new iSHELL spectrograph at the NASA Infrared Telescope facility. iShell replaces the 25 year old CSHELL with improvements in spectral grasp (~40x), resolution (70,000 versus 46,000), throughput, optics, and detector characteristics. With CSHELL, we obtained a radial velocity precision of 3 m/s on a bright red giant and we identified several radial velocity variable M dwarfs for future follow up. Our goal with iSHELL is to characterize the precise radial velocity performance of the methane isotopologue absorption gas cell in the calibration unit. We observe bright nearby radial velocity standards to better understand the instrument and data reduction techniques. We have updated our CSHELL analysis code to handle multiple orders and the increased number of pixels. It is feasible that we will obtain a radial velocity precision of < 3 m/s, sufficient to detect terrestrial planets in the habitable zone of nearby M dwarfs. We will also follow up radial velocity variables we have discovered, along with transiting exoplanets orbiting M dwarfs identified with the K2 and TESS missions.

  6. Analytic expressions for ULF wave radiation belt radial diffusion coefficients.

    PubMed

    Ozeke, Louis G; Mann, Ian R; Murphy, Kyle R; Jonathan Rae, I; Milling, David K

    2014-03-01

    We present analytic expressions for ULF wave-derived radiation belt radial diffusion coefficients, as a function of L and Kp, which can easily be incorporated into global radiation belt transport models. The diffusion coefficients are derived from statistical representations of ULF wave power, electric field power mapped from ground magnetometer data, and compressional magnetic field power from in situ measurements. We show that the overall electric and magnetic diffusion coefficients are to a good approximation both independent of energy. We present example 1-D radial diffusion results from simulations driven by CRRES-observed time-dependent energy spectra at the outer boundary, under the action of radial diffusion driven by the new ULF wave radial diffusion coefficients and with empirical chorus wave loss terms (as a function of energy, Kp and L). There is excellent agreement between the differential flux produced by the 1-D, Kp-driven, radial diffusion model and CRRES observations of differential electron flux at 0.976 MeV-even though the model does not include the effects of local internal acceleration sources. Our results highlight not only the importance of correct specification of radial diffusion coefficients for developing accurate models but also show significant promise for belt specification based on relatively simple models driven by solar wind parameters such as solar wind speed or geomagnetic indices such as Kp.

  7. Thermal analysis of a fully wet porous radial fin with natural convection and radiation using the spectral collocation method

    NASA Astrophysics Data System (ADS)

    Khani, F.; Darvishi, M. T.; Gorla, R. S.. R.; Gireesha, B. J.

    2016-05-01

    Heat transfer with natural convection and radiation effect on a fully wet porous radial fin is considered. The radial velocity of the buoyancy driven flow at any radial location is obtained by applying Darcy's law. The obtained non-dimensionalized ordinary differential equation involving three highly nonlinear terms is solved numerically with the spectral collocation method. In this approach, the dimensionless temperature is approximated by Chebyshev polynomials and discretized by Chebyshev-Gausse-Lobatto collocation points. A particular algorithm is used to reduce the nonlinearity of the conservation of energy equation. The present analysis characterizes the effect of ambient temperature in different ways and it provides a better picture regarding the effect of ambient temperature on the thermal performance of the fin. The profiles for temperature distributions and dimensionless base heat flow are obtained for different parameters which influence the heat transfer rate.

  8. An unconventional indication of the Sauve' - Kapandji procedure in a radial shaft pseudoarthrosis and chronic DRUJ dislocation: a case report.

    PubMed

    Theodorakis, E; Fanelli, M; Ottolenghi, P; Pappalardo, S

    2013-01-01

    We present a 42-years-old male who developed a radial shaft pseudoartrosis and a chronic DRUJ dislocation/instability, following a Galeazzi fracture. He presented to our Office with a severe inability of wrist and forearm motion. A Sauve'-Kapandji procedure was adopted, performing a lateral approach to the ulna and grafting the excised ulnar block to retrieve radial length at the pseudoarthrosis level. Cancellous bone grafts from the iliac crest were also applied and mixed with autologous platelet rich plasma to promote callus formation. The goal was to create an intentional pseudoarthrosis of the distal ulna combined with a DRUJ arthrodesis, in order to resolve instability and regain forearm pronation/supination. We obtained bone healing, an excellent clinical recovery, and the patient returned to all his previous activities six months after surgery. To our knowledge, this is the first reported case of a radial shaft psudoarthrosis treated with the Sauve'-Kapandji technique.

  9. Instantaneous frequency time analysis of physiology signals: The application of pregnant women’s radial artery pulse signals

    NASA Astrophysics Data System (ADS)

    Su, Zhi-Yuan; Wang, Chuan-Chen; Wu, Tzuyin; Wang, Yeng-Tseng; Tang, Feng-Cheng

    2008-01-01

    This study used the Hilbert-Huang transform, a recently developed, instantaneous frequency-time analysis, to analyze radial artery pulse signals taken from women in their 36th week of pregnancy and after pregnancy. The acquired instantaneous frequency-time spectrum (Hilbert spectrum) is further compared with the Morlet wavelet spectrum. Results indicate that the Hilbert spectrum is especially suitable for analyzing the time series of non-stationary radial artery pulse signals since, in the Hilbert-Huang transform, signals are decomposed into different mode functions in accordance with signal’s local time scale. Therefore, the Hilbert spectrum contains more detailed information than the Morlet wavelet spectrum. From the Hilbert spectrum, we can see that radial artery pulse signals taken from women in their 36th week of pregnancy and after pregnancy have different patterns. This approach could be applied to facilitate non-invasive diagnosis of fetus’ physiological signals in the future.

  10. On the nature of the radial and cross track errors for artificial earth satellites. [GEOS 2 and OAR-901

    NASA Technical Reports Server (NTRS)

    Bonavito, N. L.; Gordon, R. A.; Marsh, J. G.

    1975-01-01

    The analysis of the radial and cross track errors of artificial earth satellites is discussed in terms of the interference of two one-dimensional celestial mechanical wave trains. Resulting equations for these tracking errors describe the behavior of the uncertainties in the orbital parameters as oscillatory in nature, with a rapidly oscillating term, which is a function of the sum of the observed and computed orbital frequencies, modulated in amplitude by a slowly varying oscillation. This latter term is itself a function of either the difference between these orbital frequencies or between the values of the computed and observed right ascensions, depending upon whether it is the radial or cross track case under consideration. These results indicate that the cross track calculation describes the behavior of uncertainties in the right ascension of the ascending node and the inclination, while the radial calculation gives information on uncertainties in the semi-major axis, the eccentricity, and the argument of perigee. In addition, expressions for the radial and cross track oscillatory frequencies are obtained in terms of the orbital frequencies of the satellites. Data show that the time average of the radial and cross track errors in any case, will both approach zero.

  11. THE RADIAL METALLICITY GRADIENTS IN THE MILKY WAY THICK DISK AS FOSSIL SIGNATURES OF A PRIMORDIAL CHEMICAL DISTRIBUTION

    SciTech Connect

    Curir, A.; Serra, A. L.; Spagna, A.; Lattanzi, M. G.; Re Fiorentin, P.; Diaferio, A.

    2014-04-01

    In this Letter we examine the evolution of the radial metallicity gradient induced by secular processes, in the disk of an N-body Milky Way-like galaxy. We assign a [Fe/H] value to each particle of the simulation according to an initial, cosmologically motivated, radial chemical distribution and let the disk dynamically evolve for ∼6 Gyr. This direct approach allows us to take into account only the effects of dynamical evolution and to gauge how and to what extent they affect the initial chemical conditions. The initial [Fe/H] distribution increases with R in the inner disk up to R ≈ 10 kpc and decreases for larger R. We find that the initial chemical profile does not undergo major transformations after ∼6 Gyr of dynamical evolution. The final radial chemical gradients predicted by the model in the solar neighborhood are positive and of the same order as those recently observed in the Milky Way thick disk. We conclude that (1) the spatial chemical imprint at the time of disk formation is not washed out by secular dynamical processes and (2) the observed radial gradient may be the dynamical relic of a thick disk originated from a stellar population showing a positive chemical radial gradient in the inner regions.

  12. Kepler beaming binaries radial velocity follow-up with WIYN/Hydra

    NASA Astrophysics Data System (ADS)

    Shporer, Avi; Stassun, Keivan; Faigler, Simchon; Boyajian, Tabetha; Mazeh, Tsevi; Tal-Or, Lev; Prsa, Andrej

    2015-12-01

    High-quality space-based time series photometry reveals the minute photometric modulations induced by orbital motion in short-period binary systems with stellar and substellar secondaries. Those modulations are induced by both gravitational and atmospheric processes. Gravitational processes include the beaming effect (aka Doppler boosting) and tidal ellipsoidal distortion, and the atmospheric processes include reflected light and thermal emission by the secondary atmosphere. Therefore, non-eclipsing (non-transiting) systems are detectable using photometry alone. The availability of Kepler data for a large sample of stars combined with the sensitivity to non-eclipsing systems (which are at least an order of magnitude more common than eclipsing systems) has the potential of transforming the Kepler survey into the equivalent of a radial velocity survey of a large sample of stars. This allows detecting intrinsically rare systems, where traditional approaches, e.g., radial velocity and transit surveys, are highly inefficient. Those include systems where the companion is a brown-dwarf or a massive planet, or even a white dwarf. As this approach is still in its infancy, we are carrying out radial velocity follow-up of Kepler photometric detections, to confirm the nature of the system and accurately measure the orbit and the companion’s mass. Here we present our results from an radial velocity campaign with the WIYN/Hydra multi-fiber spectrograph, where we used 26 nights during the 2014 and 2015 Kepler observing seasons to observe five Hydra one-degree diameter fields within the Kepler field. Our list of targets includes 131 Kepler beaming binaries, and we used additional fibers to observe 85 Kepler eclipsing binaries and 31 Kepler Objects of Interest (KOIs). A detailed comparison between the photometrically predicted companion’s mass and the mass measured through radial velocities will improve our understanding of this young approach, and will support similar projects

  13. [Social aspects of left-handedness].

    PubMed

    Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

    2010-01-01

    Throughout human history left-handedness has been considered as sinful. It has been associated with the devil, weakness, female gender, unhealthiness, evil, something that has to be turned to a "good"--right side by force. Left-handedness is being more and more acceptable at rational level, but in everyday life it is still considered to be unusual if someone writes with the left hand. Lessening of the number of lefthanders is associated with ageing. There are about 13% lefthanders among people in twenties and less than 1% lefthanders among those in eighties. This finding may be explaned with more pronounced socio-cultural pressure on left-handed people in the past, compared to nowadays. On the other hand, this may also support the hypothesis about a reduced life span of lefthanded people. With cross-exercising of left-handedness, certain typical characteristics and behavioural patterns appear in these people. This was a sort of provoked behaviour and an attack on the integrity of an emotional attitude toward oneself. Stuttering may also appear as a consequence of unsuccessful cross-exercising of left-handedness. The hypothesis about left-handedness as an advantage is supported with the reports about relatively more lefthanders in some specific groups such as: mathematicians, sculptors, architects, painters, musicians, actors, tennis players, as well as famous army commanders and rulers.

  14. Surgical Treatment of Left Ventricular Pseudoaneurysm

    PubMed Central

    Mujanovic, Emir; Bergsland, Jacob; Avdic, Sevleta; Stanimirovic-Mujanovic, Sanja; Kovacevic-Preradovic, Tamara; Kabil, Emir

    2014-01-01

    Introduction: Left ventricular pseudoaneurysm is a rare condition because in most instances ventricular free-wall rupture leads to fatal pericardial tamponade. Rupture of the free wall of the left ventricle is a cata­strophic complication of myocardial infarction, occurring in approximately 4% of pa­tients with infarcts, resulting in immediate collapse of the patient and electromechanical dissociation. In rare cases the rupture is contained by pericardial and fibrous tissue, and the result is a pseudoaneurysm. The left ventricular pseudoaneurysm contains only pericardial and fibrous elements in its wall-no myocardial tissue. Because such aneurysms have a strong tendency to rupture, this disorder may lead to death if it is left surgically untreated. Case report: In this case report, we present a patient who underwent successful repair of a left ventricular pseudoaneurysm, which followed a myocardial infarction that was caused by occlusion of the left circumflex coronary artery. Although repair of left ventricular pseudoaneurysm is still a surgical challenge, it can be performed with acceptable results in most patients. PMID:25568538

  15. [Gigantic coronary aneurysm arisen from coronary fistula between the left circumflex artery and the left ventricle].

    PubMed

    Uchida, T; Andou, H; Yasutsune, T; Iwai, T; Fukumura, F; Tanaka, J

    2008-12-01

    A 71-year-old male was referred to our hospital due to abnormality detected by a chest roentgenogram. He had no symptoms except for slight chest oppression. He was found to have a giant coronary aneurysm. It was originated from a coronary artery (left circum flex branch) left ventricular fistula. The orifice of this fistula to the left ventricle was also dilated and formed diverticulum. Ligation of the feeding coronary branch, closure of the aneurysmal fistula in the left ventricular wall and aneurysmectomy were performed under cardiopulmonary bypass. Postoperative course was uneventful. A giant aneurysm originated from a coronary-left ventricular fistula was considered to be very rare.

  16. Left ventricular mechanics of counterpulsation and left heart bypass, individually and in combination.

    PubMed

    Rose, E A; Marrin, C A; Bregman, D; Spotnitz, H M

    1979-01-01

    Counterpulsation and left heart bypass devices have been successfully used to salvage patients with severe left ventricular power failure following cardiopulmonary bypass. Each of these techniques is believed to reduce or minimize myocardial work, yet the effects of these devices on the force of myocardial contraction have not been defined. In the present investigation the effects of counterpulsation produced by intravascular (intra-aortic balloon pumping) and extravascular (pulsatile assist device) balloon devices, partial left atrial-aortic bypass, and total bypass on left ventricular mechanics were examined. The devices were studied individually and in combination in 10 anesthetized open-chest dogs. Left ventricular wall stress, external work, and contractility indices were calculated by computer using a changing volume spherical model of the left ventricle. Results indicate that although all currently available circulatory assist devices reduced peak left ventricular wall stress, a spectrum of relative effectiveness progressed from intra-aortic balloon pumping or pulsatile assist device alone through the combination intra-aortic balloon pumping plus the pulsatile assist device. Partial left heart bypass was more effective than intra-aortic balloon pumping plus the pulsatile assist device in reducing peak wall stress, but the difference was small. Total left heart bypass was vastly superior to any of the other modalities tested in its effects on peak wall stress as well as external work. The addition of counterpulsation to partial or total left heart bypass produced minimal changes in left ventricular systolic mechanics.

  17. Gelastic seizures involving the left parietal lobe.

    PubMed

    Machado, René Andrade; Astencio, Adriana Goicoechea

    2012-01-01

    Gelastic seizures have been described in various epilepsies arising from the temporal or frontal lobes, although the most commonly encountered form is related to the presence of a hypothalamic hamartoma. We describe a patient with gelastic seizures involving the left parietal lobe. Our patient, an 8-year-old girl, underwent interictal video/EEG monitoring and MRI. The seizures consisted of brief staring followed by smiling and laughing. Electroencephalography during the gelastic seizures showed rhythmic spikes and waves in the left parietal lobe. MRI revealed the characteristic features of focal cortical dysplasia. Our findings suggest that the left parietal lobe may actively participate in the particular epileptogenic network generating gelastic seizures.

  18. What Lies Ahead (left-eye)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is the left-eye version of the 3-D cylindrical-perspective mosaic showing the view south of the martian crater dubbed 'Bonneville.' The image was taken by the navigation camera on the Mars Exploration Rover Spirit. The rover will travel toward the Columbia Hills, seen here at the upper left. The rock dubbed 'Mazatzal' and the hole the rover drilled in to it can be seen at the lower left. The rover's position is referred to as 'Site 22, Position 32.' This image was geometrically corrected to make the horizon appear flat.

  19. The Potential Effects of a Biofeedback Writing Exercise on Radial Artery Blood Flow and Neck Mobility

    PubMed Central

    Krullaards, Rob L.; Pel, Johan J. M.; Snijders, Chris J.; Kleinrensink, Gert-Jan

    2009-01-01

    Background: It has been suggested that sustained contraction of the deep neck muscles may reduce axial cervical range of motion (CROM) and radial artery blood flow velocity (vrad.art.mean). No studies have reported both phenomena in relation to acute hand, shoulder or neck trauma. Procedures: The CROM and vrad.art.mean were measured in 20 police officers prior to and immediately after a 2-hours drive on a motorcycle and immediately after a 1-minute writing exercise using biofeedback. The CROM was measured using separate inclinometers and the vrad.art.mean was measured in both arms just proximal to the wrist using echo-Doppler. Findings: During the study, one officer had a motorcycle accident resulting in acute symptoms of neck trauma. His vrad.art.mean was acutely reduced by 73% (right arm) and 45% (left arm). Writing with biofeedback increased his vrad.art.mean by 150% (right arm) and 80% (left arm). In the remaining 19 officers, the CROM to the right was significantly increased after the 2-hours driving task (p<0.05; paired subject t-test). Writing with biofeedback increased their CROM in both directions and vrad.art.mean in both arms (p<001). Conclusions: A 2-hours drive showed modest physical changes in the upper extremities. Biofeedback in writing tasks might relate to the influence of relaxation and diverting attention for neck mobility and arterial blood flow improvement. PMID:23675136

  20. Atomic physics processes in radial transport calculations

    SciTech Connect

    Hogan, J.T.

    1983-02-01

    These lectures were intended as preparation for detailed discussions of the role of atomic and molecular physics in confinement research at the 1982 NATO Advanced Study Institute. They begin with a description of the major approaches to magnetic confinement: tandem (ambipolar) mirrors with their associated auxiliary barriers, tokamaks, and stellarators. The leading alternatives, the ELMO Bumpy Torus and the reversed field pinch, are also treated. The evolution equations for particle, energy, and (where relevant) field diffusion are presented and discussed. This is the context for atomic and molecular processes relevant to confinement.

  1. Effects of radial motion on interchange injections at Saturn

    NASA Astrophysics Data System (ADS)

    Paranicas, C.; Thomsen, M. F.; Achilleos, N.; Andriopoulou, M.; Badman, S. V.; Hospodarsky, G.; Jackman, C. M.; Jia, X.; Kennelly, T.; Khurana, K.; Kollmann, P.; Krupp, N.; Louarn, P.; Roussos, E.; Sergis, N.

    2016-01-01

    Charged particle injections are regularly observed in Saturn's inner magnetosphere by Cassini. They are attributed to an ongoing process of flux-tube interchange driven by the strong centrifugal force associated with Saturn's rapid rotation. Numerical simulations suggest that these interchange injections can be associated with inward flow channels, in which plasma confined to a narrow range of longitudes moves radially toward the planet, gaining energy, while ambient plasma in the adjacent regions moves more slowly outward. Most previous analyses of these events have neglected this radial motion and inferred properties of the events under the assumption that they appear instantaneously at the spacecraft's L-shell and thereafter drift azimuthally. This paper describes features of injections that can be related to their radial motion prior to observation. We use a combination of phase space density profiles and an updated version of a test-particle model to quantify properties of the injection. We are able to infer the longitudinal width of the injection, the radial travel time from its point of origin, and the starting L shell of the injection. We can also predict which energies can remain inside the channel during the radial transport. To highlight the effects of radial propagation at a finite speed, we focus on those interchange injections without extensive features of azimuthal dispersion. Injections that have traveled radially for one or more hours prior to observation would have been initiated at a different local time than that of the observation. Finally, we describe an injection where particles have drifted azimuthally into a flow channel prior to observation by Cassini.

  2. Submarine radial vents on Mauna Loa Volcano, Hawai'i

    USGS Publications Warehouse

    Wanless, V. Dorsey; Garcia, M.O.; Trusdell, F.A.; Rhodes, J.M.; Norman, M.D.; Weis, Dominique; Fornari, D.J.; Kurz, M.D.; Guillou, Herve

    2006-01-01

    A 2002 multibeam sonar survey of Mauna Loa's western flank revealed ten submarine radial vents and three submarine lava flows. Only one submarine radial vent was known previously. The ages of these vents are constrained by eyewitness accounts, geologic relationships, Mn-Fe coatings, and geochemical stratigraphy; they range from 128 years B.P. to possibly 47 ka. Eight of the radial vents produced degassed lavas despite eruption in water depths sufficient to inhibit sulfur degassing. These vents formed truncated cones and short lava flows. Two vents produced undegassed lavas that created “irregular” cones and longer lava flows. Compositionally and isotopically, the submarine radial vent lavas are typical of Mauna Loa lavas, except two cones that erupted alkalic lavas. He-Sr isotopes for the radial vent lavas follow Mauna Loa's evolutionary trend. The compositional and isotopic heterogeneity of these lavas indicates most had distinct parental magmas. Bathymetry and acoustic backscatter results, along with photography and sampling during four JASON2 dives, are used to produce a detailed geologic map to evaluate Mauna Loa's submarine geologic history. The new map shows that the 1877 submarine eruption was much larger than previously thought, resulting in a 10% increase for recent volcanism. Furthermore, although alkalic lavas were found at two radial vents, there is no systematic increase in alkalinity among these or other Mauna Loa lavas as expected for a dying volcano. These results refute an interpretation that Mauna Loa's volcanism is waning. The submarine radial vents and flows cover 29 km2 of seafloor and comprise a total volume of ∼2×109 m3 of lava, reinforcing the idea that submarine lava eruptions are important in the growth of oceanic island volcanoes even after they emerged above sea level.

  3. Judet type-IV radial neck fractures in children

    PubMed Central

    Kaiser, Margarita; Eberl, Robert; Castellani, Christoph; Kraus, Tanja; Till, Holger; Singer, Georg

    2016-01-01

    Background and purpose Heavily displaced radial neck fractures in children are sometimes associated with poor outcome. A substantial number of these fractures require open reduction. We hypothesized that Judet type-IV fractures with a completely displaced radial head would result in a worse outcome than radial neck fractures with remaining bony contact. Patients and methods We analyzed 19 children (median age 9.7 (4–13) years) who were treated for Judet type-IV radial neck fractures between 2001 and 2014. The outcome was assessed at the latest outpatient visit using the Linscheid-Wheeler score at a median time of 3.5 (1–8) years after injury. The patients were assigned either to group A (9 fractures with remaining bony contact between the radial head and the radial neck) or to group B (10 fractures without any bony contact). Results The 2 groups were similar concerning age and sex. The rate of additional injuries was higher in group B (7/10 vs. 1/9 in group A; p = 0.009). The rate of open reduction was higher in group B (5/10 vs. 0/9 in group A; p = 0.01). Poor outcome was more common in group B (4/10 vs. 0/9 in group A; p = 0.03). In group B, the proportion of children with poor outcome (almost half) was the same irrespective of whether open or closed reduction had been done. Interpretation The main causes of unfavorable results of radial neck fracture in children appear to be related to the energy of the injury and the amount of displacement—and not to whether open reduction was used. PMID:27348024

  4. Analytic expressions for ULF wave radiation belt radial diffusion coefficients

    PubMed Central

    Ozeke, Louis G; Mann, Ian R; Murphy, Kyle R; Jonathan Rae, I; Milling, David K

    2014-01-01

    We present analytic expressions for ULF wave-derived radiation belt radial diffusion coefficients, as a function of L and Kp, which can easily be incorporated into global radiation belt transport models. The diffusion coefficients are derived from statistical representations of ULF wave power, electric field power mapped from ground magnetometer data, and compressional magnetic field power from in situ measurements. We show that the overall electric and magnetic diffusion coefficients are to a good approximation both independent of energy. We present example 1-D radial diffusion results from simulations driven by CRRES-observed time-dependent energy spectra at the outer boundary, under the action of radial diffusion driven by the new ULF wave radial diffusion coefficients and with empirical chorus wave loss terms (as a function of energy, Kp and L). There is excellent agreement between the differential flux produced by the 1-D, Kp-driven, radial diffusion model and CRRES observations of differential electron flux at 0.976 MeV—even though the model does not include the effects of local internal acceleration sources. Our results highlight not only the importance of correct specification of radial diffusion coefficients for developing accurate models but also show significant promise for belt specification based on relatively simple models driven by solar wind parameters such as solar wind speed or geomagnetic indices such as Kp. Key Points Analytic expressions for the radial diffusion coefficients are presented The coefficients do not dependent on energy or wave m value The electric field diffusion coefficient dominates over the magnetic PMID:26167440

  5. A passively suspended Tesla pump left ventricular assist device.

    PubMed

    Izraelev, Valentin; Weiss, William J; Fritz, Bryan; Newswanger, Raymond K; Paterson, Eric G; Snyder, Alan; Medvitz, Richard B; Cysyk, Joshua; Pae, Walter E; Hicks, Dennis; Lukic, Branka; Rosenberg, Gerson

    2009-01-01

    The design and initial test results of a new passively suspended Tesla type left ventricular assist device blood pump are described. Computational fluid dynamics (CFD) analysis was used in the design of the pump. Overall size of the prototype device is 50 mm in diameter and 75 mm in length. The pump rotor has a density lower than that of blood and when spinning inside the stator in blood it creates a buoyant centering force that suspends the rotor in the radial direction. The axial magnetic force between the rotor and stator restrain the rotor in the axial direction. The pump is capable of pumping up to 10 L/min at a 70 mm Hg head rise at 8,000 revolutions per minute (RPM). The pump has demonstrated a normalized index of hemolysis level below 0.02 mg/dL for flows between 2 and 9.7 L/min. An inlet pressure sensor has also been incorporated into the inlet cannula wall and will be used for control purposes. One initial in vivo study showed an encouraging result. Further CFD modeling refinements are planned and endurance testing of the device.

  6. Off-pump insertion of an extracorporeal LVAD through a left upper-quadrant incision.

    PubMed

    Cohn, William E; Frazier, O H

    2006-01-01

    Insertion of an extracorporeal left ventricular assist device for temporary ventricular support via median sternotomy can be challenging in patients with a history of cardiac surgery, because these patients often poorly tolerate the lengthy dissection and cardiac manipulation necessary for exposure of the left ventricular apex and ascending aorta. Our approach, transdiaphragmatic left ventricular inflow cannulation with return through a graft sewn to the supraceliac aorta, can be accomplished through a left upper-quadrant abdominal incision without entering the peritoneal cavity, mediastinum, or left hemithorax. Repeated sternotomy and mediastinal dissection are thus avoided. To our knowledge, this report documents the 1st use of this technique for insertion of an extracorporeal pulsatile ventricular assist device for temporary ventricular support.

  7. A review on plasma-assisted VLS synthesis of silicon nanowires and radial junction solar cells

    NASA Astrophysics Data System (ADS)

    Misra, Soumyadeep; Yu, Linwei; Chen, Wanghua; Foldyna, Martin; Cabarrocas, Pere Roca i.

    2014-10-01

    Incorporation of nanostructures is a recent trend in the photovoltaic community, aimed at improving light absorption and consequently cell efficiency. In this regard, semiconductor nanowires provide an attractive research platform for a new generation of cost-effective and efficient solar cells. Thanks to their unique geometry, silicon nanowires enhance light trapping and anti-reflection effects by means of multiple scattering between individual nanowires, and by coupling the light into confined eigenmodes over a broad range of the solar spectrum. Moreover, radial junction solar cells built around nanowires decouple the light absorption and carrier collection directions, which allows for a higher internal field and better carrier collection. Thus, arrays of radial junction solar cells bring advantages of high efficiency with reduced material amount. This is particularly attractive for devices based on hydrogenated amorphous and microcrystalline silicon thin films. In this paper, after reviewing different approaches to fabricate silicon nanowires, we focus on nanowires grown using the plasma-assisted vapour-liquid-solid method because of the simplicity and compatibility with current silicon thin-film technology. Their application to a-Si : H based radial junction solar cells has already resulted in ˜8% of stable devices with an absorber layer thickness of only 100 nm. Moreover, current challenges and perspectives such as the use of a microcrystalline silicon absorber are also reviewed.

  8. Radial diffusion in Saturn's radiation belts - A modeling analysis assuming satellite and ring E absorption

    NASA Technical Reports Server (NTRS)

    Hood, L. L.

    1983-01-01

    A modeling analysis is carried out of six experimental phase space density profiles for nearly equatorially mirroring protons using methods based on the approach of Thomsen et al. (1977). The form of the time-averaged radial diffusion coefficient D(L) that gives an optimal fit to the experimental profiles is determined under the assumption that simple satellite plus Ring E absorption of inwardly diffusing particles and steady-state radial diffusion are the dominant physical processes affecting the proton data in the L range that is modeled. An extension of the single-satellite model employed by Thomsen et al. to a model that includes multisatellite and ring absorption is described, and the procedures adopted for estimating characteristic satellite and ring absorption times are defined. The results obtained in applying three representative solid-body absorption models to evaluate D(L) in the range where L is between 4 and 16 are reported, and a study is made of the sensitivity of the preferred amplitude and L dependence for D(L) to the assumed model parameters. The inferred form of D(L) is then compared with that which would be predicted if various proposed physical mechanisms for driving magnetospheric radial diffusion are operative at Saturn.

  9. RADIAL VELOCITY ALONG THE VOYAGER 1 TRAJECTORY: THE EFFECT OF SOLAR CYCLE

    SciTech Connect

    Pogorelov, N. V.; Zank, G. P.; Borovikov, S. N.; Burlaga, L. F.; Decker, R. A.; Stone, E. C.

    2012-05-01

    As Voyager 1 and Voyager 2 are approaching the heliopause (HP)-the boundary between the solar wind (SW) and the local interstellar medium (LISM)-we expect new, unknown features of the heliospheric interface to be revealed. A seeming puzzle reported recently by Krimigis et al. concerns the unusually low, even negative, radial velocity components derived from the energetic ion distribution. Steady-state plasma models of the inner heliosheath (IHS) show that the radial velocity should not be equal to zero even at the surface of the HP. Here we demonstrate that the velocity distributions observed by Voyager 1 are consistent with time-dependent simulations of the SW-LISM interaction. In this Letter, we analyze the results from a numerical model of the large-scale heliosphere that includes solar cycle effects. Our simulations show that prolonged periods of low to negative radial velocity can exist in the IHS at substantial distances from the HP. It is also shown that Voyager 1 was more likely to observe such regions than Voyager 2.

  10. Radial junction amorphous silicon solar cells on PECVD-grown silicon nanowires.

    PubMed

    Yu, Linwei; O'Donnell, Benedict; Foldyna, Martin; Roca i Cabarrocas, Pere

    2012-05-17

    Constructing radial junction hydrogenated amorphous silicon (a-Si:H) solar cells on top of silicon nanowires (SiNWs) represents a promising approach towards high performance and cost-effective thin film photovoltaics. We here develop an all-in situ strategy to grow SiNWs, via a vapour-liquid-solid (VLS) mechanism on top of ZnO-coated glass substrate, in a plasma-enhanced chemical vapour deposition (PECVD) reactor. Controlling the distribution of indium catalyst drops allows us to tailor the as-grown SiNW arrays into suitable size and density, which in turn results in both a sufficient light trapping effect and a suitable arrangement allowing for conformal coverage of SiNWs by subsequent a-Si:H layers. We then demonstrate the fabrication of radial junction solar cells and carry on a parametric study designed to shed light on the absorption and quantum efficiency response, as functions of the intrinsic a-Si:H layer thickness and the density of SiNWs. These results lay a solid foundation for future structural optimization and performance ramp-up of the radial junction thin film a-Si:H photovoltaics.

  11. Magneto-fluorescent hybrid of dye and SPION with ordered and radially distributed porous structures

    NASA Astrophysics Data System (ADS)

    Gogoi, Madhulekha; Deb, Pritam

    2014-04-01

    We have reported the development of a silica based magneto-fluorescent hybrid of a newly synthesized dye and superparamagnetic iron oxide nanoparticles with ordered and radially distributed porous structure. The dye is synthesized by a novel yet simple synthetic approach based on Michael addition between dimer of glutaraldehyde and oleylamine molecule. The surfactant used for phase transformation of the dye from organic to aqueous phase, also acts as a structure directing agent for the porous structure evolution of the hybrid with radial distribution. The evolution of the radially distributed pores in the hybrids can be attributed to the formation of rod-like micelles containing nanoparticles, for concentration of micelles greater than critical micelle concentration. A novel water extraction method is applied to remove the surfactants resulting in the characteristic porous structure of the hybrid. Adsorption isotherm analysis confirms the porous nature of the hybrids with pore diameter ∼2.4 nm. A distinct modification in optical and magnetic property is observed due to interaction of the dye and SPION within the silica matrix. The integration of multiple structural components in the so developed hybrid nanosystem results into a potential agent for multifunctional biomedical application.

  12. An Uncommon Combination of Fractures around the Elbow: Capitellum Fracture Associated with Radial Head Fracture

    PubMed Central

    Walid, Osman; Meriem, Braiki; Zeineb, Alaya; Nader, Naouar; Mohamed, Ben Ayeche

    2016-01-01

    Introduction: The coexistence of fractures of capitulum humeri and radial head in the elbow joint is a rare entity. Case Report: A 30-year-old woman was admitted to our hospital after having sustained a fall on her outstretched right arm. She complained of pain, swelling, and restriction of motion of the right elbow joint. Anteroposterior and lateral radiographs revealed displaced fractures in the capitellum and the radial head. The patient was operated. Fractures were exposed through a lateral (Kocher) incision. Fracture was reduced, and fixation was performed with 2 AO compression screw. Two fragments of radial head fracture were also reduced and fixed with AO compression screw. Clinical and radiographic outcomes were excellent at the end of a 5-year follow-up. Conclusion: These fractures occurred following a fall on the palm with outstretched arm. The success of the treatment depends greatly on surgical approach and suitable technique which requires comprehensive knowledge of detailed anatomy and biomechanics of the elbow. PMID:28164067

  13. A model for particle confinement in a toroidal plasma subject to strong radial electric fields

    NASA Technical Reports Server (NTRS)

    Roth, J. R.

    1977-01-01

    The approach adopted in the NASA Lewis Bumpy Torus experiment is to confine and heat a toroidal plasma by the simultaneous application of strong dc magnetic fields and electric fields. Strong radial electric fields (about 1 kV/cm) are imposed by biasing the plasma with up to 12 negative electrode rings which surround its minor circumference. The plasma containment is consistent with a balance of two processes: a radial infusion of ions in those sectors not containing electrode rings, resulting from the radially inward electric fields; and ion losses to the electrode rings, each of which acts as a sink and draws ions out the plasma in the manner of a Langmuir probe in the ion saturation regime. The highest density on axis which has been observed so far in this steady-state plasma is 6.2 trillion particles per cu cm, for which the particle containment time is 2.5 msec. The deuterium ion kinetic temperature for these conditions was in the range of 360 to 520 eV.

  14. Improvement of the CULTEX(®) exposure technology by radial distribution of the test aerosol.

    PubMed

    Aufderheide, Michaela; Heller, Wolf-Dieter; Krischenowski, Olaf; Möhle, Niklas; Hochrainer, Dieter

    2017-03-02

    The exposure of cellular based systems cultivated on microporous membranes at the air-liquid interface (ALI) has been accepted as an appropriate approach to simulate the exposure of cells of the respiratory tract to native airborne substances. The efficiency of such an exposure procedure with regard to stability and reproducibility depends on the optimal design at the interface between the cellular test system and the exposure technique. The actual exposure systems favor the dynamic guidance of the airborne substances to the surface of the cells in specially designed exposure devices. Two module types, based on a linear or radial feed of the test atmosphere to the test system, were used for these studies. In our technical history, the development started with the linear designed version, the CULTEX(®) glass modules, fulfilling basic requirements for running ALI exposure studies (Mohr and Durst, 2005). The instability in the distribution of different atmospheres to the cells caused us to create a new exposure module, characterized by a stable and reproducible radial guidance of the aerosol to the cells. The outcome was the CULTEX(®) RFS (Mohr et al., 2010). In this study, we describe the differences between the two systems with regard to particle distribution and deposition clarifying the advantages and disadvantages of a radial to a linear aerosol distribution concept.

  15. Hydrallazine alone in acute left ventricular failure

    PubMed Central

    Clark, A. J. L.; McMichael, H. B.

    1981-01-01

    A patient presented with severe acute left ventricular failure and was treated with hydrallazine and oxygen alone. He made a rapid and full recovery as judged by clinical, radiological and blood gas evidence. ImagesFig. 1 PMID:7329902

  16. Individual differences in left parietal white matter predict math scores on the Preliminary Scholastic Aptitude Test.

    PubMed

    Matejko, Anna A; Price, Gavin R; Mazzocco, Michèle M M; Ansari, Daniel

    2013-02-01

    Mathematical skills are of critical importance, both academically and in everyday life. Neuroimaging research has primarily focused on the relationship between mathematical skills and functional brain activity. Comparatively few studies have examined which white matter regions support mathematical abilities. The current study uses diffusion tensor imaging (DTI) to test whether individual differences in white matter predict performance on the math subtest of the Preliminary Scholastic Aptitude Test (PSAT). Grades 10 and 11 PSAT scores were obtained from 30 young adults (ages 17-18) with wide-ranging math achievement levels. Tract based spatial statistics was used to examine the correlation between PSAT math scores, fractional anisotropy (FA), radial diffusivity (RD) and axial diffusivity (AD). FA in left parietal white matter was positively correlated with math PSAT scores (specifically in the left superior longitudinal fasciculus, left superior corona radiata, and left corticospinal tract) after controlling for chronological age and same grade PSAT critical reading scores. Furthermore, RD, but not AD, was correlated with PSAT math scores in these white matter microstructures. The negative correlation with RD further suggests that participants with higher PSAT math scores have greater white matter integrity in this region. Individual differences in FA and RD may reflect variability in experience dependent plasticity over the course of learning and development. These results are the first to demonstrate that individual differences in white matter are associated with mathematical abilities on a nationally administered scholastic aptitude measure.

  17. Left ventricular myxoma: a case report

    PubMed Central

    Qin, Wei; Wang, Liming; Chen, Xin; Liu, Peisheng; Wang, Rui

    2014-01-01

    Cardiac myxoma, the most common primary heart tumor, is located mainly in the left atrium. We reported a rare case of left ventricular myxoma incidentally found on echocardiography in an asymptomatic 60-year-old male. The tumor was carefully resected without fragmentation. The patient had an uneventful recovery and was discharged home on the 4th postoperative day. Surgical resection of this type of cardiac myxoma is recommended due to the rarity of tumor location. PMID:25469121

  18. Development of a used fuel cladding damage model incorporating circumferential and radial hydride responses

    NASA Astrophysics Data System (ADS)

    Chen, Qiushi; Ostien, Jakob T.; Hansen, Glen

    2014-04-01

    At the completion of the fuel drying process, used fuel Zry4 cladding typically exhibits a significant population of δ-hydride inclusions. These inclusions are in the form of small platelets that are generally oriented both circumferentially and radially within the cladding material. There is concern that radially-oriented hydride inclusions may weaken the cladding material and lead to issues during used fuel storage and transportation processes. A high fidelity model of the mechanical behavior of hydrides has utility in both designing fuel cladding to be more resistant to this hydride-induced weakening and also in suggesting modifications to drying, storage, and transport operations to reduce the impact of hydride formation and/or the avoidance of loading scenarios that could overly stress the radial inclusions. We develop a mechanical model for the Zry4-hydride system that, given a particular morphology of hydride inclusions, allows the calculation of the response of the hydrided cladding under various loading scenarios. The model treats the Zry4 matrix material as J2 elastoplastic, and treats the hydrides as platelets oriented in predefined directions (e.g., circumferentially and radially). The model is hosted by the Albany analysis framework, where a finite element approximation of the weak form of the cladding boundary value problem is solved using a preconditioned Newton-Krylov approach. Instead of forming the required system Jacobian operator directly or approximating its action with a differencing operation, Albany leverages the Trilinos Sacado package to form the Jacobian via automatic differentiation. We present results that describe the performance of the model in comparison with as-fabricated Zry4 as well as HB Robinson fuel cladding. Further, we also present performance results that demonstrate the efficacy of the overall solution method employed to host the model.

  19. Powdery Mildew Decreases the Radial Growth of Oak Trees with Cumulative and Delayed Effects over Years.

    PubMed

    Bert, Didier; Lasnier, Jean-Baptiste; Capdevielle, Xavier; Dugravot, Aline; Desprez-Loustau, Marie-Laure

    2016-01-01

    Quercus robur and Q. petraea are major European forest tree species. They have been affected by powdery mildew caused by Erysiphe alphitoides for more than a century. This fungus is a biotrophic foliar pathogen that diverts photosynthetate from the plant for its own nutrition. We used a dendrochronological approach to investigate the effects of different levels of infection severity on the radial growth of young oak trees. Oak infection was monitored at individual tree level, at two sites in southwestern France, over a five-year period (2001-2005). Mean infection severity was almost 75% (infected leaf area) at the end of the 2001 growing season, at both sites, but only about 40% in 2002, and 8%, 5% and 2% in 2003, 2004 and 2005, respectively. Infection levels varied considerably between trees and were positively related between 2001 and 2002. Increment cores were taken from each tree to assess annual ring widths and increases in basal area. Annual radial growth was standardised to take the effect of tree size into account. Annual standardised radial growth was significantly and negatively correlated with infection severity in the same year, for both 2001 and 2002, and at both sites. The decrease in growth reached 70-90% for highly infected trees. The earlywood width was poorly correlated with infection severity, but the proportion of latewood in tree rings was lower in highly infected trees (60%) than in less heavily infected trees (85%). Infection in 2001 and 2002 was found to have a cumulative effect on radial growth in these years, together with a delayed effect detectable in 2003. Thus, even non-lethal pathogens like powdery mildew can have a significant impact on tree functioning. This impact should be taken into account in growth and yield models, to improve predictions of forest net primary production.

  20. Temporary scaphocapitate fixation with or without radial shortening for adolescent Kienböck's disease.

    PubMed

    Cha, Soo Min; Shin, Hyun Dae; Ahn, Jae Sung; Noh, Chang Kyun

    2015-05-01

    We performed temporary scaphocapitate joint fixation with or without radial shortening osteotomy, depending on the ulnar variance, in adolescent Kienböck's disease. The aim of the current study was to evaluate the radiological and clinical results and compare our results with those of other previously reported methods. Temporary scaphocapitate fixation alone or fixation accompanied by radial shortening osteotomy has been performed in three patients since 2003. All six patients were males, and their mean age at surgery was 15.5 years. The fixation was performed using two Kirschner-wires in closed methods, and the shortening of the radius was performed using the volar approach and secured with a plate. Radial shortenings of 4, 2, and 7 mm were applied. Radiological findings of Kienböck's disease, including ulnar variance and carpal height ratio, were investigated at the final follow-up by simple radiography and MRI. Clinical results of pain, range of wrist motion, and grip strength were also evaluated. The mean age at the final follow-up of six patients was 22 years, and the follow-up period was 6.8 years. Sclerosis or fragmentation of all the lunates in the simple radiographs improved, and the carpal height ratio increased to 0.5 at the final follow-up. The signal intensities on the final MRI were all normalized. The final visual analog scale scores decreased to 1.2, and wrist ranges of motion were all statistically significantly increased. In addition, grip strength increased to 69% of that of the normal side at the final follow-up. We suggest that temporary scaphocapitate joint fixation is a recommendable option with or without radial shortening, depending on the ulnar variance, in adolescent Kienböck's disease.

  1. Ultrasonic Technology Improves Radial Artery Puncture and Cannulation in Intensive Care Unit (ICU) Shock Patients

    PubMed Central

    Li, Xiuyan; Fang, Guizhen; Yang, Danhua; Wang, Lanfang; Zheng, Chunmei; Ruan, Longjuan; Wang, Lingcong

    2016-01-01

    Background This study observed the efficacy of ultrasonic technique with out-of-plane orientation and in-plane guidance in radial artery puncture and cannulation in intensive care unit (ICU) shock patients to elucidate the effect of this technique on the security of cannulation. Material/Methods A total of 88 ICU shock patients, randomized into a palpation (control) group and an ultrasound (experimental) group, received continuous intravenous sedation and analgesia. The palpation group patients underwent radial artery cannulation using the traditional palpation pulsation approach, and the ultrasound group patients underwent radial artery cannulation under out-of-plane orientation and in-plane guidance using an ultrasonic apparatus. Data were recorded and compared between the 2 groups. Results (1) The success rate of the first puncture in the ultrasound group and the palpation group was 80% and 42%, respectively (P<0.05). (2) The cannulation duration in the ultrasound group and the palpation group was 8.77±6.33 s and 28.7±26.33 s, respectively (P<0.01). (3) Incidence of hematoma and staxis around stoma in the ultrasound group was 2.5% and 5%, respectively, which was significantly lower than that in the palpation group, which was 20% and 32.5%, respectively (P<0.05). (4) Time to achieve the early goal-directed therapy in the ultrasound group and the palpation group was 306.73±39.98 min and 356.75±40.97 min, respectively (P<0.01). Conclusions Compared with the traditional method, radial artery cannulation with out-of-plane orientation and in-plane guidance is a quick and secure cannulation method and is appropriate for use in clinics. PMID:27397118

  2. Powdery Mildew Decreases the Radial Growth of Oak Trees with Cumulative and Delayed Effects over Years

    PubMed Central

    Bert, Didier; Lasnier, Jean-Baptiste; Capdevielle, Xavier; Dugravot, Aline; Desprez-Loustau, Marie-Laure

    2016-01-01

    Quercus robur and Q. petraea are major European forest tree species. They have been affected by powdery mildew caused by Erysiphe alphitoides for more than a century. This fungus is a biotrophic foliar pathogen that diverts photosynthetate from the plant for its own nutrition. We used a dendrochronological approach to investigate the effects of different levels of infection severity on the radial growth of young oak trees. Oak infection was monitored at individual tree level, at two sites in southwestern France, over a five-year period (2001–2005). Mean infection severity was almost 75% (infected leaf area) at the end of the 2001 growing season, at both sites, but only about 40% in 2002, and 8%, 5% and 2% in 2003, 2004 and 2005, respectively. Infection levels varied considerably between trees and were positively related between 2001 and 2002. Increment cores were taken from each tree to assess annual ring widths and increases in basal area. Annual radial growth was standardised to take the effect of tree size into account. Annual standardised radial growth was significantly and negatively correlated with infection severity in the same year, for both 2001 and 2002, and at both sites. The decrease in growth reached 70–90% for highly infected trees. The earlywood width was poorly correlated with infection severity, but the proportion of latewood in tree rings was lower in highly infected trees (60%) than in less heavily infected trees (85%). Infection in 2001 and 2002 was found to have a cumulative effect on radial growth in these years, together with a delayed effect detectable in 2003. Thus, even non-lethal pathogens like powdery mildew can have a significant impact on tree functioning. This impact should be taken into account in growth and yield models, to improve predictions of forest net primary production. PMID:27177029

  3. Simulating MODFLOW-based reactive transport under radially symmetric flow conditions.

    PubMed

    Wallis, Ilka; Prommer, Henning; Post, Vincent; Vandenbohede, Alexander; Simmons, Craig T

    2013-01-01

    Radially symmetric flow and solute transport around point sources and sinks is an important specialized topic of groundwater hydraulics. Analysis of radial flow fields is routinely used to determine heads and flows in the vicinity of point sources or sinks. Increasingly, studies also consider solute transport, biogeochemical processes, and thermal changes that occur in the vicinity of point sources/sinks. Commonly, the analysis of hydraulic processes involves numerical or (semi-) analytical modeling methods. For the description of solute transport, analytical solutions are only available for the most basic transport phenomena. Solving advanced transport problems numerically is often associated with a significant computational burden. However, where axis-symmetry applies, computational cost can be decreased substantially in comparison with full three-dimensional (3D) solutions. In this study, we explore several techniques of simulating conservative and reactive transport within radial flow fields using MODFLOW as the flow simulator, based on its widespread use and ability to be coupled with multiple solute and reactive transport codes of different complexity. The selected transport simulators are MT3DMS and PHT3D. Computational efficiency and accuracy of the approaches are evaluated through comparisons with full 2D/3D model simulations, analytical solutions, and benchmark problems. We demonstrate that radial transport models are capable of accurately reproducing a wide variety of conservative and reactive transport problems provided that an adequate spatial discretization and advection scheme is selected. For the investigated test problems, the computational load was substantially reduced, with the improvement varying, depending on the complexity of the considered reaction network.

  4. Effects of a left ventricular assist device with a centrifugal pump on left ventricular diastolic hemodynamics.

    PubMed

    Saito, Akira

    2002-10-01

    The purpose of this investigation was to analyze how left ventricular assist device (LVAD) with a centrifugal pump alters left ventricular diastolic hemodynamics and energy by means of a left ventricular pressure volume relationship. Fifteen anesthetized normal pig hearts were studied after placement of an apical drainage LVAD with a centrifugal pump. Indices of the left ventricular isovolumic relaxation phase, left ventricular filling phase and general hemodynamic data were recorded with the LVAD in on and off situations. The pump assist rate was adjusted to 25%, 50% and 75%. Left ventricular stroke work, with a high correlation with oxygen consumption, decreased as the assist rate increased. Left ventricular relaxation delayed as the assist rate increased, but the atrioventricular pressure gradient increased in the left ventricular rapid filling phase. This finding clarifies left ventricular rapid filling. In this study, it was suggested that although left ventricular isovolumic relaxation was affected, 75% assistance is the most effective for the pump flow in terms of circulation support and restoration of cardiac function.

  5. The Effect of Radial Migration on Galactic Disks

    NASA Astrophysics Data System (ADS)

    Vera-Ciro, Carlos; D'Onghia, Elena; Navarro, Julio; Abadi, Mario

    2014-10-01

    We study the radial migration of stars driven by recurring multi-arm spiral features in an exponential disk embedded in a dark matter halo. The spiral perturbations redistribute angular momentum within the disk and lead to substantial radial displacements of individual stars, in a manner that largely preserves the circularity of their orbits and that results, after 5 Gyr (~40 full rotations at the disk scale length), in little radial heating and no appreciable changes to the vertical or radial structure of the disk. Our results clarify a number of issues related to the spatial distribution and kinematics of migrators. In particular, we find that migrators are a heavily biased subset of stars with preferentially low vertical velocity dispersions. This "provenance bias" for migrators is not surprising in hindsight, for stars with small vertical excursions spend more time near the disk plane, and thus respond more readily to non-axisymmetric perturbations. We also find that the vertical velocity dispersion of outward migrators always decreases, whereas the opposite holds for inward migrators. To first order, newly arrived migrators simply replace stars that have migrated off to other radii, thus inheriting the vertical bias of the latter. Extreme migrators might therefore be recognized, if present, by the unexpectedly small amplitude of their vertical excursions. Our results show that migration, understood as changes in angular momentum that preserve circularity, can strongly affect the thin disk, but cast doubts on models that envision the Galactic thick disk as a relic of radial migration.

  6. Radial elasticity of multi-walled boron nitride nanotubes

    SciTech Connect

    Michael W. Smith, Cheol Park, Meng Zheng, Changhong Ke ,In-Tae Bae, Kevin Jordan

    2012-02-01

    We investigated the radial mechanical properties of multi-walled boron nitride nanotubes (MW-BNNTs) using atomic force microscopy. The employed MW-BNNTs were synthesized using pressurized vapor/condenser (PVC) methods and were dispersed in aqueous solution using ultrasonication methods with the aid of ionic surfactants. Our nanomechanical measurements reveal the elastic deformational behaviors of individual BNNTs with two to four tube walls in their transverse directions. Their effective radial elastic moduli were obtained through interpreting their measured radial deformation profiles using Hertzian contact mechanics models. Our results capture the dependences of the effective radial moduli of MW-BNNTs on both the tube outer diameter and the number of tube layers. The effective radial moduli of double-walled BNNTs are found to be several-fold higher than those of single-walled BNNTs within the same diameter range. Our work contributes directly to a complete understanding of the fundamental structural and mechanical properties of BNNTs and the pursuits of their novel structural and electronics applications.

  7. Radial elasticity of multi-walled boron nitride nanotubes.

    PubMed

    Zheng, Meng; Ke, Changhong; Bae, In-Tae; Park, Cheol; Smith, Michael W; Jordan, Kevin

    2012-03-09

    We investigated the radial mechanical properties of multi-walled boron nitride nanotubes (MW-BNNTs) using atomic force microscopy. The employed MW-BNNTs were synthesized using pressurized vapor/condenser (PVC) methods and were dispersed in aqueous solution using ultrasonication methods with the aid of ionic surfactants. Our nanomechanical measurements reveal the elastic deformational behaviors of individual BNNTs with two to four tube walls in their transverse directions. Their effective radial elastic moduli were obtained through interpreting their measured radial deformation profiles using Hertzian contact mechanics models. Our results capture the dependences of the effective radial moduli of MW-BNNTs on both the tube outer diameter and the number of tube layers. The effective radial moduli of double-walled BNNTs are found to be several-fold higher than those of single-walled BNNTs within the same diameter range. Our work contributes directly to a complete understanding of the fundamental structural and mechanical properties of BNNTs and the pursuits of their novel structural and electronics applications.

  8. Accretion, radial flows and abundance gradients in spiral galaxies

    NASA Astrophysics Data System (ADS)

    Pezzulli, Gabriele; Fraternali, Filippo

    2016-01-01

    The metal-poor gas continuously accreting on to the discs of spiral galaxies is unlikely to arrive from the intergalactic medium (IGM) with exactly the same rotation velocity as the galaxy itself and even a small angular momentum mismatch inevitably drives radial gas flows within the disc, with significant consequences to galaxy evolution. Here, we provide some general analytic tools to compute accretion profiles, radial gas flows and abundance gradients in spiral galaxies as a function of the angular momentum of the accreting material. We generalize existing solutions for the decomposition of the gas flows, required to reproduce the structural properties of galaxy discs, into direct accretion from the IGM and a radial mass flux within the disc. We then solve the equation of metallicity evolution in the presence of radial gas flows with a novel method, based on characteristic lines, which greatly reduces the numerical demand on the computation and sheds light on the crucial role of boundary conditions on the abundance profiles predicted by theoretical models. We also discuss how structural and chemical constraints can be combined to disentangle the contributions of inside-out growth and radial flows in the development of abundance gradients in spiral galaxies. Illustrative examples are provided throughout with parameters plausible for the Milky Way. We find that the material accreting on the Milky Way should rotate at 70-80 per cent of the rotational velocity of the disc, in agreement with previous estimates.

  9. Cell boundary analysis using radial search for dual staining techniques

    NASA Astrophysics Data System (ADS)

    Iftikhar, Saadia; Bharath, Anil Anthony

    2009-02-01

    In medical image analysis and segmentation, many conventional methods work very well on good quality tissue section images, but often fail when the images are not of good quality. Active contours or snakes are widely used in medical image processing applications especially for boundary detection. However, the problems with initialization and poor performance of snakes on noisy images limit their efficacy. As an alternative, this research presents an efficient and robust method to segment cell nuclei and their respective boundaries for low contrast cell images using a combination of a radial search and interpolation methods. This radial search method can be used in medical image analysis and segmentation applications for images which are very noisy or whose structural regions are not very clear. The processes in this method consists of (1) extracting the location of the cell nuclei (2) finding the edge information of the given image (3) applying radial search on the edge image patch for finding the radial initialization and finally (4) using an interpolation method to find the desired boundary points, which describe the potential boundary points to best fit to that candidate shape or cell. The results shown on the images of branch aorta of rabbit are suggesting that the proposed radial search method correctly finds the boundaries even on very low contrast images, which can be used for further medical image analysis.

  10. Relation between Radial and Axial Losses in Tandem Mirrors

    NASA Astrophysics Data System (ADS)

    Pratt, J.; Horton, W.; Berk, H. L.

    2006-04-01

    The tandem mirror still remains a potentially attractive magnetic confinement geometry. The absence of toroidal curvature and internal plasma parallel current gives the system strongly favorable stability. Additionally, GAMMA-10 experimental results demonstrate that sheared rotation can suppress turbulent radial losses. For an MHD stable system, we investigate the interplay between drift wave (ITG, ETG and Bohm) radial transport and axial losses. Using empirical energy confinement scaling laws from large ITER and ISS databases as upper bounds on the radial loss rates, we simulate radial transport using a transport barrier dynamics (TBD) code. Simulations are carried out for a machine of volume 212 m^3 (central cell length/radius 30 m/1.5 m) with central cell field 3 T. ITER stores 7022 MJ of energy in the toroidal magnetic field; in our tandem mirror design this energy is reduced to 954 MJ. Our simulations show that high core temperatures result in long Pastukhov loss times; drift wave radial transport dominates, except at the plasma edge, where pitch angle scattering causes losses.

  11. Radial elasticity of multi-walled boron nitride nanotubes

    NASA Astrophysics Data System (ADS)

    Zheng, Meng; Ke, Changhong; Bae, In-Tae; Park, Cheol; Smith, Michael W.; Jordan, Kevin

    2012-03-01

    We investigated the radial mechanical properties of multi-walled boron nitride nanotubes (MW-BNNTs) using atomic force microscopy. The employed MW-BNNTs were synthesized using pressurized vapor/condenser (PVC) methods and were dispersed in aqueous solution using ultrasonication methods with the aid of ionic surfactants. Our nanomechanical measurements reveal the elastic deformational behaviors of individual BNNTs with two to four tube walls in their transverse directions. Their effective radial elastic moduli were obtained through interpreting their measured radial deformation profiles using Hertzian contact mechanics models. Our results capture the dependences of the effective radial moduli of MW-BNNTs on both the tube outer diameter and the number of tube layers. The effective radial moduli of double-walled BNNTs are found to be several-fold higher than those of single-walled BNNTs within the same diameter range. Our work contributes directly to a complete understanding of the fundamental structural and mechanical properties of BNNTs and the pursuits of their novel structural and electronics applications.

  12. Dust particle radial confinement in a dc glow discharge.

    PubMed

    Sukhinin, G I; Fedoseev, A V; Antipov, S N; Petrov, O F; Fortov, V E

    2013-01-01

    A self-consistent nonlocal model of the positive column of a dc glow discharge with dust particles is presented. Radial distributions of plasma parameters and the dust component in an axially homogeneous glow discharge are considered. The model is based on the solution of a nonlocal Boltzmann equation for the electron energy distribution function, drift-diffusion equations for ions, and the Poisson equation for a self-consistent electric field. The radial distribution of dust particle density in a dust cloud was fixed as a given steplike function or was chosen according to an equilibrium Boltzmann distribution. The balance of electron and ion production in argon ionization by an electron impact and their losses on the dust particle surface and on the discharge tube walls is taken into account. The interrelation of discharge plasma and the dust cloud is studied in a self-consistent way, and the radial distributions of the discharge plasma and dust particle parameters are obtained. It is shown that the influence of the dust cloud on the discharge plasma has a nonlocal behavior, e.g., density and charge distributions in the dust cloud substantially depend on the plasma parameters outside the dust cloud. As a result of a self-consistent evolution of plasma parameters to equilibrium steady-state conditions, ionization and recombination rates become equal to each other, electron and ion radial fluxes become equal to zero, and the radial component of electric field is expelled from the dust cloud.

  13. The effect of radial migration on galactic disks

    SciTech Connect

    Vera-Ciro, Carlos; D'Onghia, Elena; Navarro, Julio; Abadi, Mario

    2014-10-20

    We study the radial migration of stars driven by recurring multi-arm spiral features in an exponential disk embedded in a dark matter halo. The spiral perturbations redistribute angular momentum within the disk and lead to substantial radial displacements of individual stars, in a manner that largely preserves the circularity of their orbits and that results, after 5 Gyr (∼40 full rotations at the disk scale length), in little radial heating and no appreciable changes to the vertical or radial structure of the disk. Our results clarify a number of issues related to the spatial distribution and kinematics of migrators. In particular, we find that migrators are a heavily biased subset of stars with preferentially low vertical velocity dispersions. This 'provenance bias' for migrators is not surprising in hindsight, for stars with small vertical excursions spend more time near the disk plane, and thus respond more readily to non-axisymmetric perturbations. We also find that the vertical velocity dispersion of outward migrators always decreases, whereas the opposite holds for inward migrators. To first order, newly arrived migrators simply replace stars that have migrated off to other radii, thus inheriting the vertical bias of the latter. Extreme migrators might therefore be recognized, if present, by the unexpectedly small amplitude of their vertical excursions. Our results show that migration, understood as changes in angular momentum that preserve circularity, can strongly affect the thin disk, but cast doubts on models that envision the Galactic thick disk as a relic of radial migration.

  14. The left side of motor resonance

    PubMed Central

    Sartori, Luisa; Begliomini, Chiara; Panozzo, Giulia; Garolla, Alice; Castiello, Umberto

    2014-01-01

    Motor resonance is defined as the internal activation of an observer's motor system, specifically attuned to the perceived movement. In social contexts, however, different patterns of observed and executed muscular activation are frequently required. This is the case, for instance, of seeing a key offered with a precision grip and received by opening the hand. Novel evidence suggests that compatibility effects in motor resonance can be altered by social response preparation. What is not known is how handedness modulates this effect. The present study aimed at determining how a left- and a right-handed actor grasping an object and then asking for a complementary response influences corticospinal activation in left- and right-handers instructed to observe the scene. Transcranial magnetic stimulation (TMS)-induced motor evoked potentials (MEPs) were thus recorded from the dominant hands of left- and right-handers. Interestingly, requests posed by the right-handed actor induced a motor activation in the participants' respective dominant hands, suggesting that left-handers tend to mirror right-handers with their most efficient hand. Whereas requests posed by the left-handed actor activated the anatomically corresponding muscles (i.e., left hand) in all the participants, right-handers included. Motor resonance effects classically reported in the literature were confirmed when observing simple grasping actions performed by the right-handed actor. These findings indicate that handedness influences both congruent motor resonance and complementary motor preparation to observed actions. PMID:25249966

  15. Mapping the convergent temporal epileptic network in left and right temporal lobe epilepsy.

    PubMed

    Fang, Peng; An, Jie; Zeng, Ling-Li; Shen, Hui; Qiu, Shijun; Hu, Dewen

    2017-02-03

    Left and right mesial temporal lobe epilepsy (mTLE) with hippocampal sclerosis (HS) exhibits similar functional and clinical dysfunctions, such as depressive mood and emotional dysregulation, implying that the left and right mTLE may share a common network substrate. However, the convergent anatomical network disruption between the left and right HS remains largely uncharacterized. This study aimed to investigate whether the left and right mTLE share a similar anatomical network. We examined 43 (22 left, 21 right) mTLE patients with HS and 39 healthy controls using diffusion tensor imaging. Machine learning approaches were applied to extract the abnormal anatomical connectivity patterns in both the left and right mTLE. The left and right mTLE showed that 28 discriminating connections were exactly the same when compared to the controls. The same 28 connections showed high discriminating power in comparisons of the left mTLE versus controls (91.7%) and the right mTLE versus controls (90.0%); however, these connections failed to discriminate the left from the right mTLE. These discriminating connections, which were diminished both in the left and right mTLE, were primarily located in the limbic-frontal network, partially agreeing with the limbic-frontal dysregulation model of depression. These findings suggest that left and right mTLE share a convergent circuit, which may account for the mood and emotional deficits in mTLE and may suggest the neuropathological mechanisms underlying the comorbidity of depression and mTLE.

  16. Left ventricular atrioventricular plane displacement is preserved with lifelong endurance training and is the main determinant of maximal cardiac output.

    PubMed

    Steding-Ehrenborg, Katarina; Boushel, Robert C; Calbet, José A; Åkeson, Per; Mortensen, Stefan P

    2015-12-01

    Age-related decline in cardiac function can be prevented or postponed by lifelong endurance training. However, effects of normal ageing as well as of lifelong endurance exercise on longitudinal and radial contribution to stroke volume are unknown. The aim of this study was to determine resting longitudinal and radial pumping in elderly athletes, sedentary elderly and young sedentary subjects. Furthermore, we aimed to investigate determinants of maximal cardiac output in elderly. Eight elderly athletes (63 ± 4 years), seven elderly sedentary (66 ± 4 years) and ten young sedentary subjects (29 ± 4 years) underwent cardiac magnetic resonance imaging. All subjects underwent maximal exercise testing and for elderly subjects maximal cardiac output during cycling was determined using a dye dilution technique. Longitudinal and radial contribution to stroke volume did not differ between groups (longitudinal left ventricle (LV) 52-65%, P = 0.12, right ventricle (RV) 77-87%, P = 0.16, radial 7.9-8.6%, P = 1.0). Left ventricular atrioventricular plane displacement (LVAVPD) was higher in elderly athletes and young sedentary compared with elderly sedentary subjects (14 ± 3, 15 ± 2 and 11 ± 1 mm, respectively, P < 0.05). There was no difference between groups for RVAVPD (P = 0.2). LVAVPD was an independent predictor of maximal cardiac output (R(2) = 0.61, P < 0.01, β = 0.78). Longitudinal and radial contributions to stroke volume did not differ between groups. However, how longitudinal pumping was achieved differed; elderly athletes and young sedentary subjects showed similar AVPD whereas this was significantly lower in elderly sedentary subjects. Elderly sedentary subjects achieved longitudinal pumping through increased short-axis area of the ventricle. Large AVPD was a determinant of maximal cardiac output and exercise capacity.

  17. Modeling left-turn crash occurrence at signalized intersections by conflicting patterns.

    PubMed

    Wang, Xuesong; Abdel-Aty, Mohamed

    2008-01-01

    In order to better understand the underlying crash mechanisms, left-turn crashes occurring at 197 four-legged signalized intersections over 6 years were classified into nine patterns based on vehicle maneuvers and then were assigned to intersection approaches. Crash frequency of each pattern was modeled at the approach level by mainly using Generalized Estimating Equations (GEE) with the Negative Binomial as the link function to account for the correlation among the crash data. GEE with a binomial logit link function was also applied for patterns with fewer crashes. The Cumulative Residuals test shows that, for correlated left-turn crashes, GEE models usually outperformed basic Negative Binomial models. The estimation results show that there are obvious differences in the factors that cause the occurrence of different left-turn collision patterns. For example, for each pattern, the traffic flows to which the colliding vehicles belong are identified to be significant. The width of the crossing distance (represented by the number of through lanes on the opposing approach of the left-turning traffic) is associated with more left-turn traffic colliding with opposing through traffic (Pattern 5), but with less left-turning traffic colliding with near-side crossing through traffic (Pattern 8). The safety effectiveness of the left-turning signal is not consistent for different crash patterns; "protected" phasing is correlated with fewer Pattern 5 crashes, but with more Pattern 8 crashes. The study indicates that in order to develop efficient countermeasures for left-turn crashes and improve safety at signalized intersections, left-turn crashes should be considered in different patterns.

  18. Combined baseline strain dyssynchrony index and its acute reduction predicts mid-term left ventricular reverse remodeling and long-term outcome after cardiac resynchronization therapy.

    PubMed

    Tatsumi, Kazuhiro; Tanaka, Hidekazu; Matsumoto, Kensuke; Miyoshi, Tatsuya; Hiraishi, Mana; Tsuji, Takayuki; Kaneko, Akihiro; Ryo, Keiko; Fukuda, Yuko; Norisada, Kazuko; Onishi, Tetsuari; Yoshida, Akihiro; Kawai, Hiroya; Hirata, Ken-ichi

    2014-04-01

    The objective of this study was to test the hypothesis that combining assessment of baseline radial strain dyssynchrony index (SDI), that expressed both left ventricular (LV) dyssynchrony and residual myocardial contractility, and of acute changes in this index can yield more accurate prediction of mid-term responders and long-term outcome after cardiac resynchronization therapy (CRT). Radial SDI for 75 CRT patients was calculated as the average difference between peak and end-systolic speckle tracking strain from 6 segments of the mid-LV short-axis view before and 8 ± 2 days after CRT. Mid-term responder was defined as ≥ 15% decrease in LV end-systolic volume 6 ± 2 months after CRT. Long-term outcome was tracked over 5 years. Baseline radial SDI ≥ 6.5% is considered predictive of responder and favorable outcome, as previously reported. Acute reduction in radial SDI ≥ 1.5% was found to be the best predictor of mid-term responders with CRT. Furthermore, patients with acute reductions in radial SDI ≥1.5% were associated with a significantly more favorable long-term outcome after CRT than those with radial SDI <1.5% (log rank P < 0.001). An important findings were that baseline radial SDI ≥6.5% and acute reductions in radial SDI ≥ 1.5% in 42 patients were associated with the highest event-free survival rate of 92%, whereas, 21 patients corresponding values of <6.5% and <1.5% were associated with low event-free survival rate of 46% (log rank P < 0.001). Combined assessment of baseline radial SDI and its acute reduction after CRT may have clinical implications for predicting responders and thus patients' care.

  19. Left ventricular strain and its pattern estimated from cine CMR and validation with DENSE

    NASA Astrophysics Data System (ADS)

    Gao, Hao; Allan, Andrew; McComb, Christie; Luo, Xiaoyu; Berry, Colin

    2014-07-01

    Measurement of local strain provides insight into the biomechanical significance of viable myocardium. We attempted to estimate myocardial strain from cine cardiovascular magnetic resonance (CMR) images by using a b-spline deformable image registration method. Three healthy volunteers and 41 patients with either recent or chronic myocardial infarction (MI) were studied at 1.5 Tesla with both cine and DENSE CMR. Regional circumferential and radial left ventricular strains were estimated from cine and DENSE acquisitions. In all healthy volunteers, there was no difference for peak circumferential strain (- 0.18 ± 0.04 versus - 0.18 ± 0.03, p = 0.76) between cine and DENSE CMR, however peak radial strain was overestimated from cine (0.84 ± 0.37 versus 0.49 ± 0.2, p < 0.01). In the patient study, the peak strain patterns predicted by cine were similar to the patterns from DENSE, including the strain evolution related to recovery time and strain patterns related to MI scar extent. Furthermore, cine-derived strain disclosed different strain patterns in MI and non-MI regions, and regions with transmural and non-transmural MI as DENSE. Although there were large variations with radial strain measurements from cine CMR images, useful circumferential strain information can be obtained from routine clinical CMR imaging. Cine strain analysis has potential to improve the diagnostic yield from routine CMR imaging in clinical practice.

  20. Left ventricular strain and its pattern estimated from cine CMR and validation with DENSE.

    PubMed

    Gao, Hao; Allan, Andrew; McComb, Christie; Luo, Xiaoyu; Berry, Colin

    2014-07-07

    Measurement of local strain provides insight into the biomechanical significance of viable myocardium. We attempted to estimate myocardial strain from cine cardiovascular magnetic resonance (CMR) images by using a b-spline deformable image registration method. Three healthy volunteers and 41 patients with either recent or chronic myocardial infarction (MI) were studied at 1.5 Tesla with both cine and DENSE CMR. Regional circumferential and radial left ventricular strains were estimated from cine and DENSE acquisitions. In all healthy volunteers, there was no difference for peak circumferential strain (- 0.18 ± 0.04 versus - 0.18 ± 0.03, p = 0.76) between cine and DENSE CMR, however peak radial strain was overestimated from cine (0.84 ± 0.37 versus 0.49 ± 0.2, p < 0.01). In the patient study, the peak strain patterns predicted by cine were similar to the patterns from DENSE, including the strain evolution related to recovery time and strain patterns related to MI scar extent. Furthermore, cine-derived strain disclosed different strain patterns in MI and non-MI regions, and regions with transmural and non-transmural MI as DENSE. Although there were large variations with radial strain measurements from cine CMR images, useful circumferential strain information can be obtained from routine clinical CMR imaging. Cine strain analysis has potential to improve the diagnostic yield from routine CMR imaging in clinical practice.

  1. The importance of premotor cortex for supporting speech production after left capsular-putaminal damage.

    PubMed

    Seghier, Mohamed L; Bagdasaryan, Juliana; Jung, Dorit E; Price, Cathy J

    2014-10-22

    The left putamen is known to be important for speech production, but some patients with left putamen damage can produce speech remarkably well. We investigated the neural mechanisms that support this recovery by using a combination of techniques to identify the neural regions and pathways that compensate for loss of the left putamen during speech production. First, we used fMRI to identify the brain regions that were activated during reading aloud and picture naming in a patient with left putamen damage. This revealed that the patient had abnormally high activity in the left premotor cortex. Second, we used dynamic causal modeling of the patient's fMRI data to understand how this premotor activity influenced other speech production regions and whether the same neural pathway was used by our 24 neurologically normal control subjects. Third, we validated the compensatory relationship between putamen and premotor cortex by showing, in the control subjects, that lower connectivity through the putamen increased connectivity through premotor cortex. Finally, in a lesion-deficit analysis, we demonstrate the explanatory power of our fMRI results in new patients who had damage to the left putamen, left premotor cortex, or both. Those with damage to both had worse reading and naming scores. The results of our four-pronged approach therefore have clinical implications for predicting which patients are more or less likely to recover their speech after left putaminal damage.

  2. An adaptive left-right eigenvector evolution algorithm for vibration isolation control

    NASA Astrophysics Data System (ADS)

    Wu, T. Y.

    2009-11-01

    The purpose of this research is to investigate the feasibility of utilizing an adaptive left and right eigenvector evolution (ALREE) algorithm for active vibration isolation. As depicted in the previous paper presented by Wu and Wang (2008 Smart Mater. Struct. 17 015048), the structural vibration behavior depends on both the disturbance rejection capability and mode shape distributions, which correspond to the left and right eigenvector distributions of the system, respectively. In this paper, a novel adaptive evolution algorithm is developed for finding the optimal combination of left-right eigenvectors of the vibration isolator, which is an improvement over the simultaneous left-right eigenvector assignment (SLREA) method proposed by Wu and Wang (2008 Smart Mater. Struct. 17 015048). The isolation performance index used in the proposed algorithm is defined by combining the orthogonality index of left eigenvectors and the modal energy ratio index of right eigenvectors. Through the proposed ALREE algorithm, both the left and right eigenvectors evolve such that the isolation performance index decreases, and therefore one can find the optimal combination of left-right eigenvectors of the closed-loop system for vibration isolation purposes. The optimal combination of left-right eigenvectors is then synthesized to determine the feedback gain matrix of the closed-loop system. The result of the active isolation control shows that the proposed method can be utilized to improve the vibration isolation performance compared with the previous approaches.

  3. Quantitative analysis of left ventricular function as a tool in clinical research. Theoretical basis and methodology.

    PubMed

    San Román, José Alberto; Candell-Riera, Jaume; Arnold, Roman; Sánchez, Pedro L; Aguadé-Bruix, Santiago; Bermejo, Javier; Revilla, Ana; Villa, Adolfo; Cuéllar, Hug; Hernández, Carolina; Fernández-Avilés, Francisco

    2009-05-01

    The usefulness the left ventricular ejection fraction as a surrogate endpoint in clinical trials has been confirmed by numerous studies. However, if this approach is to be applied successfully, images must be acquired in a rigorously controlled manner, and it is advisable to use measurement units that have been specifically developed for quantitative analysis of the imaging parameters obtained with current imaging techniques. This review summarizes what is now known about the left ventricular ejection fraction and left ventricular volumes, discusses the importance of measurement units in image analysis, and describes the different imaging techniques available. Finally, there is a discussion of how to select the best imaging technique for specific clinical applications.

  4. A Left Ventricular Thrombus in a Patient With Primary Antiphospholipid Syndrome Removed Under Thoracoscopic Support.

    PubMed

    Suzuki, Kota; Totsugawa, Toshinori; Hiraoka, Arudo; Tamura, Kentaro; Chikazawa, Genta; Ishida, Atsuhisa; Sakaguchi, Taichi; Yoshitaka, Hidenori

    2016-08-01

    The antiphospholipid syndrome is an autoimmune disorder characterized by vascular thrombosis. Left ventricular thrombus with antiphospholipid syndrome is rare, and there are few reports regarding surgical resection of such cases. We report the case of a 45-year-old woman who had been diagnosed as having primary antiphospholipid syndrome and was admitted to our hospital for treatment of left ventricular thrombus detected by an echocardiography. The thrombus was completely removed using video-assisted thoracoscopy through a right minithoracotomy. Left ventricular thrombectomy through a right minithoracotomy in a patient with antiphospholipid syndrome has not been previously reported. This approach is less invasive and more effective in such coagulation system disorders.

  5. Acute myocardial infarction caused by left atrial myxoma: Role of intracoronary catheter aspiration.

    PubMed

    Al-Fakhouri, Ahmad; Janjua, Muhammad; DeGregori, Michele

    2017-01-01

    Acute ST-segment elevation myocardial infarction (STEMI) caused by left atrial myxoma is very rare. Catheter-based approaches or thrombolytic therapy are mostly the first step in the management of STEMI with less time delay. We report a case of acute anterior/lateral STEMI caused by a left atrial myxoma. The patient was successfully treated by intracoronary aspiration with an Export aspiration catheter, with excellent distal coronary flow. Intracoronary catheter aspiration in acute myocardial infarction caused by a left atrial myxoma may help to salvage the infarcting myocardium with less time delay.

  6. Radial distribution function imaging by STEM diffraction: Phase mapping and analysis of heterogeneous nanostructured glasses.

    PubMed

    Mu, Xiaoke; Wang, Di; Feng, Tao; Kübel, Christian

    2016-09-01

    Characterizing heterogeneous nanostructured amorphous materials is a challenging topic, because of difficulty to solve disordered atomic arrangement in nanometer scale. We developed a new transmission electron microscopy (TEM) method to enable phase analysis and mapping of heterogeneous amorphous structures. That is to combine scanning TEM (STEM) diffraction mapping, radial distribution function (RDF) analysis, and hyperspectral analysis. This method was applied to an amorphous zirconium oxide and zirconium iron multilayer system, and showed extreme sensitivity to small atomic packing variations. This approach helps to understand local structure variations in glassy composite materials and provides new insights to correlate structure and properties of glasses.

  7. Note: On the Universality of Proximal Radial Distribution Functions of Proteins

    SciTech Connect

    Lin, Bin; Pettitt, Bernard M.

    2011-03-10

    Protein hydration is important to protein structure and function. Molecular distribution functions have been an invaluable tool to study protein hydration. Proximal radial distribution functions (pRDFs) have been postulated as being transferable across proteins based on evidence collected from two proteins [V. A. Makarov, B. K. Andrews, and B. M. Pettitt, Biopolymers 45(7), 469 (1998)]. Here we selected nine proteins with different sizes as well as different secondary topologies. We show that pRDFs are universal for proteins with compact structures. We further compare these pRDFs with those calculated from polyglycines that have no defined structures to consider the extent of the validity of this approach.

  8. Advanced radial inflow turbine rotor program: Design and dynamic testing

    NASA Technical Reports Server (NTRS)

    Rodgers, C.

    1976-01-01

    The advancement of small, cooled, radial inflow turbine technology in the area of operation at higher turbine inlet temperature is discussed. The first step was accomplished by designing, fabricating, and subjecting to limited mechanical testing an advanced gas generator rotating assembly comprising a radial inflow turbine and two-stage centrifugal compressor. The radial inflow turbine and second-stage compressor were designed as an integrally machined monorotor with turbine cooling taking place basically by conduction to the compressor. Design turbine inlet rotor gas temperature, rotational speed, and overall gas generator compressor pressure ratio were 1422 K (2560 R), 71,222 rpm, and 10/1 respectively. Mechanical testing on a fabricated rotating assembly and bearing system covered 1,000 cold start/stop cycles and three spins to 120 percent design speed (85,466 rpm).

  9. Detection of radial motion depends on spatial displacement.

    PubMed

    de la Malla, Cristina; López-Moliner, Joan

    2010-06-01

    Nakayama and Tyler (1981) disentangled the use of pure motion (speed) information from spatial displacement information for the detection of lateral motion. They showed that when positional cues were removed the contribution of motion or spatial information was dependent on the temporal frequency: for temporal frequencies lower than 1Hz the mechanism used to detect motion relied on speed information while for higher temporal frequencies a mechanism based on displacement information was used. Here we test whether the same dependency is also revealed in radial motion. In order to do so, we adapted the paradigm previously used by Nakayama and Tyler to obtain detection thresholds for lateral and radial motion by using a 2-IFC procedure. Subjects had to report which of the intervals contained the signal stimulus (33% coherent motion). We replicated the temporal frequency dependency for lateral motion but results indicate, however, that the detection of radial is always consistent with detecting a spatial displacement amplitude.

  10. [Ultrasound guided radial artery cannulation: procedure description and literature review].

    PubMed

    Carmona Monge, F J; Martínez Lareo, M; Núñez Reiz, A

    2011-01-01

    Arterial catheterization is the second most common invasive procedure performed in critical care units. These devices are essential in certain types of patients (the hemodinamically unstable or those who require regular evaluation of the gasometric values). Complications related to arterial cannulation are relatively scarce. However, there are no reliable indicators to predict the occurrence of radial artery occlusions or ischemic lesions in the hand after a radial cannulation procedure has been performed. Ultrasound-guided catheter insertion has been used for years to guide central venous cannulation in critical care, but its use has been more limited for arterial catheterization. This paper aims to describe the technique of ultrasound-guided radial artery catheterization and reviews the most important research papers that have evaluated the safety and efficacy of this procedure in the adult population.

  11. Radial line method for rear-view mirror distortion detection

    NASA Astrophysics Data System (ADS)

    Rahmah, Fitri; Kusumawardhani, Apriani; Setijono, Heru; Hatta, Agus M.; Irwansyah, .

    2015-01-01

    An image of the object can be distorted due to a defect in a mirror. A rear-view mirror is an important component for the vehicle safety. One of standard parameters of the rear-view mirror is a distortion factor. This paper presents a radial line method for distortion detection of the rear-view mirror. The rear-view mirror was tested for the distortion detection by using a system consisting of a webcam sensor and an image-processing unit. In the image-processing unit, the captured image from the webcam were pre-processed by using smoothing and sharpening techniques and then a radial line method was used to define the distortion factor. It was demonstrated successfully that the radial line method could be used to define the distortion factor. This detection system is useful to be implemented such as in Indonesian's automotive component industry while the manual inspection still be used.

  12. Radial pulsation stability as a function of hydrogen abundance

    NASA Astrophysics Data System (ADS)

    Jeffery, Simon; Saio, Hideyuki

    2015-08-01

    Following the discovery of pulsation in an extremely low-mass pre-white dwarf by Maxted et al. (2011, 2013), Jeffery & Saio (2013) showed that pulsations in such stars would be excited in high radial overtones provided that the driving zone was sufficiently depleted in hydrogen. Following previous work which shows that pulsations are more easily excited in stars where the damping effects of hydrogen are somehow reduced (Jeffery & Saio 2006), we have completed a survey of radial pulsation stability across a substantially larger parameter space. The object is to identify new regions of the HR diagram where stars should be unstable to radial pulsations, or where closely related p-modes might be excited. These would enable targeted surveys for new classes of pulsating variable. This poster reports the survey results and the identification of new instability regions.

  13. Radial nodalization effects on BWR (boiling water reactor) stability calculations

    SciTech Connect

    March-Leuba, J.

    1990-01-01

    Computer simulations have shown that stability calculations in boiling water reactors (BWRs) are very sensitive to a number of input parameters and modeling assumptions. In particular, the number of thermohydraulic regions (i.e., channels) used in the calculation can affect the results of decay ratio calculations by as much as 30%. This paper presents the background theory behind the observed effects of radial nodalization in BWR stability calculations. The theory of how a radial power distribution can be simulated in time or frequency domain codes by using representative'' regions is developed. The approximations involved in this method of solution are reviewed, and some examples of the effect of radial nodalization are presented based on LAPUR code solutions. 2 refs., 4 figs., 2 tabs.

  14. Stellar Mass Radial Profiles of Pan-STARRS MDS Galaxies

    NASA Astrophysics Data System (ADS)

    Zheng, Zheng; Thilker, D. A.; Heckman, T. M.

    2013-01-01

    Six-band (ugrizy) surface brightness radial profiles are derived for a sample of 48 late-type face-on non-interacting nearby galaxies using the Pan-STARRS Medium Deep Survey stack imaging (grizy) and the CFHT deep u-band imaging data. The surface brightnesses are measured down to ~ 29-30 ABmag/arcsec^2. The SB radial profiles are then fed into the advanced SED fitting software MAGPHYS (da Cunha et al. 2008) to derive radial profiles of stellar mass surface density as well as other parameters, such as metallicity and star formation history. The output stellar mass surface density profiles can be classified into three types (single exponential, down-bending, and up-bending), which is consistent with the results of Polen & Trujillo (2006). But the up-bending profiles are more common than indicated in PT06.

  15. Influence of White-Coat Hypertension on Left Ventricular Deformation 2- and 3-Dimensional Speckle Tracking Study.

    PubMed

    Tadic, Marijana; Cuspidi, Cesare; Ivanovic, Branislava; Ilic, Irena; Celic, Vera; Kocijancic, Vesna

    2016-03-01

    We sought to compare left ventricular deformation in subjects with white-coat hypertension to normotensive and sustained hypertensive patients. This cross-sectional study included 139 untreated subjects who underwent 24-hour ambulatory blood pressure monitoring and completed 2- and 3-dimensional examination. Two-dimensional left ventricular multilayer strain analysis was also performed. White-coat hypertension was diagnosed if clinical blood pressure was elevated and 24-hour blood pressure was normal. Our results showed that left ventricular longitudinal and circumferential strains gradually decreased from normotensive controls across subjects with white-coat hypertension to sustained hypertensive group. Two- and 3-dimensional left ventricular radial strain, as well as 3-dimensional area strain, was not different between groups. Two-dimensional left ventricular longitudinal and circumferential strains of subendocardial and mid-myocardial layers gradually decreased from normotensive control to sustained hypertensive group. Longitudinal and circumferential strains of subepicardial layer did not differ between the observed groups. We concluded that white-coat hypertension significantly affects left ventricular deformation assessed by 2-dimensional traditional strain, multilayer strain, and 3-dimensional strain.

  16. Interhemispheric transcallosal connectivity between the left and right planum temporale predicts musicianship, performance in temporal speech processing, and functional specialization.

    PubMed

    Elmer, Stefan; Hänggi, Jürgen; Jäncke, Lutz

    2016-01-01

    Currently, there is strong evidence showing that musicianship favours functional and structural changes of the left planum temporale (PT), and that these cortical reorganizations facilitate the discrimination of temporal speech cues. Based on the proposition of a division of labour between the left and right PT, here we postulated that the musicians' advantage in processing temporal speech cues and PT specialization origin, at least in part, from increased white matter connectivity between the two auditory-related cortices. In particular, we assume that increased transcallosal PT connectivity might promote functional specialization and asymmetry of homotopic brain regions. With this purpose in mind, we applied diffusion tensor imaging and compared axial diffusivity (AD), radial diffusivity (RD), and fractional anisotropy (FA) of the interhemispheric connection between the left and right PT in thirteen musicians and 13 nonmusicians. Furthermore, in the form of an addendum, we integrated cortical surface area values and blood oxygenation level dependent (BOLD) responses of the left PT that were collected in the context of two previous studies conducted with the same sample of subjects. Our results indicate increased connectivity between the left and right PT in musicians compared to nonmusicians, as indexed by reduced mean RD. We did not find significant between-group differences in FA and AD. Most notably, RD was related to the performance in the phonetic categorization task, musical aptitudes, as well as to BOLD responses in the left PT. Hence, we provide first evidence for a relationship between PT connectivity, musicianship, and phonetic categorization.

  17. Negative participation of the left posterior fascicle in the reentry circuit of verapamil-sensitive idiopathic left ventricular tachycardia.

    PubMed

    Morishima, Itsuro; Nogami, Akihiko; Tsuboi, Hideyuki; Sone, Takahito

    2012-05-01

    Left posterior fascicle and idiopathic Left VT. The left posterior fascicle may be a bystander of the circuit of verapamil-sensitive idiopathic left ventricular tachycardia. During ventricular tachycardia (VT), 3 sequences of potentials were seen at the left posterior septum: diastolic Purkinje potentials propagating from base to apex and presystolic left posterior fascicular potentials and systolic left ventricular (LV) myocardial potentials propagating in the reverse direction. Selective capture of the left posterior fascicle by the sinus beat did not affect the VT cycle length. Entrainment pacing revealed that the retrograde limb of the circuit was not the left posterior fascicle, but the LV myocardium.

  18. RADIAL STELLAR PULSATION AND THREE-DIMENSIONAL CONVECTION. II. TWO-DIMENSIONAL CONVECTION IN FULL AMPLITUDE RADIAL PULSATION

    SciTech Connect

    Geroux, Chris M.; Deupree, Robert G.

    2013-07-10

    We have developed a three-dimensional radiation hydrodynamics code to simulate the interaction of convection and radial pulsation in classical variable stars. One key goal is the ability to carry these simulations to full amplitude in order to compare them with observed light curves. Previous multi-dimensional calculations were prevented from reaching full amplitude because of drift in the radial coordinate system, due to the algorithm defining radial movement of the coordinate system during the pulsation cycle. We have removed this difficulty by defining our radial coordinate flow algorithm to require that the mass in a spherical shell remain constant for every time step throughout the pulsation cycle. We have used our new code to perform two-dimensional (2D) simulations of the interaction of radial pulsation and convection. We have made comparisons between light curves from our 2D convective simulations with observed light curves and find that our 2D simulated light curves are better able to match the observed light curve shape near the red edge of the RR Lyrae instability strip than light curves from previous one-dimensional time-dependent convective models.

  19. Factors influencing the radial-tangential illusion in haptic perception.

    PubMed

    McFarland, James; Soechting, John F

    2007-04-01

    According to the radial-tangential illusion, in the horizontal plane, arm movements executed in directions radial to the trunk are sensed to be longer than movements of the same length in the orthogonal direction. It has been suggested that the illusion arises from the fact that radially directed movements are executed more slowly and require more effort. These suggestions were tested in a series of experiments, using a robotically controlled manipulandum. In all of the experiments subjects grasped the handle of the manipulandum, in some cases exploring the virtual boundary of a rectangle, while in others being guided along a rectangular contour by the robot. In a two-alternative forced choice design, subjects reported whether the rectangle was wide or narrow. In a control experiment, subjects manifested the radial-tangential illusion. Contrary to the hypothesis, the magnitude of this illusion was not altered when a resistive force was added in the tangential direction or when the ratio of movement times in the tangential and radial directions was changed. However, when the contour was explored in the counterclockwise direction, the illusion was much smaller than when it was explored in the clockwise direction. A second series of experiments, in which subjects only explored two sides (i.e., an L-shape), demonstrated that this effect arose from distortions induced by the serial ordering of the exploratory movements. The illusion was much smaller when the radial segment was explored first. We suggest that this distortion arises from the serial nature of haptic exploration, in which the length of the initial segment decreases as it is stored in working memory for subsequent comparison.

  20. Pulmonary Hypertension Secondary to Left Ventricular Systolic Dysfunction: Contemporary Diagnosis and Management

    PubMed Central

    Shah, Ravi V.; Semigran, Marc J.

    2011-01-01

    Pulmonary hypertension secondary to left ventricular systolic dysfunction is often a poor prognostic marker in chronic heart failure. In this article, we review evidence supporting modern strategies addressing pulmonary hypertension in patients with left ventricular systolic dysfunction, including right-sided heart catheterization with vasoreactivity testing and subsequent parenteral, oral, and inhaled therapy. We delineate a diagnostic approach to secondary pulmonary hypertension and outline evidence-based therapeutic strategies for management in acute and chronic heart failure. PMID:19032918