Zhu, Jieqing; Li, Pengyun; Wu, Tinghe; Gao, Feng; Ding, Yi; Zhang, Catherine W-H; Rao, Zihe; Gao, George F; Tien, Po
2003-05-01
Fusion of paramyxovirus to the cell involves receptor binding of the HN glycoprotein and a number of conformational changes of F glycoprotein. The F protein is expressed as a homotrimer on the virus surface. In the present model, there are at least three conformations of F protein, i.e. native form, pre-hairpin intermediate and the post-fusion state. In the post-fusion state, the two highly conserved heptad repeat (HR) regions of F protein form a stable 6-helix coiled-coil bundle. However, no crystal structure is known for this state for the Newcastle disease virus, although the crystal structure of the F protein native form has been solved recently. Here we deployed an Escherichia coli in vitro expression system to engineer this 6-helix bundle by fusion of either the two HR regions (HR1, linker and HR2) or linking the 6-helix [3 x (HR1, linker and HR2)] together as a single chain. Subsequently, both of them form a stable 6-helix bundle in vitro judging by gel filtration and chemical cross-linking and the proteins show salient features of an alpha-helix structure. Crystals diffracting X-rays have been obtained from both protein preparations and the structure determination is under way. This method could be used for crystallization of the post-fusion state HR structures of other viruses.
DEFF Research Database (Denmark)
Bussink, Barbara E; Holst, Anders Gaarsdal; Jespersen, Lasse
2013-01-01
AimsTo determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population.Methods and resultsWe followed 18 441 participants included.......5%/2.3% in women, P Right bundle branch block was associated with significantly...... increased all-cause and cardiovascular mortality in both genders with age-adjusted hazard ratios (HR) of 1.31 [95% confidence interval (CI), 1.11-1.54] and 1.87 (95% CI, 1.48-2.36) in the gender pooled analysis with little attenuation after multiple adjustment. Right bundle branch block was associated...
DEFF Research Database (Denmark)
Risum, Niels; Strauss, David; Sogaard, Peter
2013-01-01
The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...
DEFF Research Database (Denmark)
Risum, Niels; Strauss, David; Sogaard, Peter;
2013-01-01
The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...
[Bundle-branch block depending on the heart rate].
Apostolov, L
1975-01-01
Five patients are reported, admitted to the hospital, with diseases predominantly of the cardio-vascular system. During the electrocardiographic examinations bundle branch block was established, depending on heart rate. It fluctuated within the physiological limits from 50 to 90/min. In three of the patients, the bundle branch block appeared with the quickening of the heart rate (tachycardia-depending bundle branch block) and in two of the patients--the bundle branch block appeared during the slowing down of the heart action and disappeared with its quickening (bradicardia-depending bundle branch block). A brief literature review is presented and attention is paid to the possible diagnostic errors and the treatment mode of those patients with cardiac tonic and antiarrhythmic medicaments.
Is It Complete Left Bundle Branch Block? Just Ablate the Right Bundle.
Ali, Hussam; Lupo, Pierpaolo; Foresti, Sara; De Ambroggi, Guido; Epicoco, Gianluca; Fundaliotis, Angelica; Cappato, Riccardo
2017-03-01
Complete left bundle branch block (LBBB) is established according to standard electrocardiographic criteria. However, functional LBBB may be rate-dependent or can perpetuate during tachycardia due to repetitive concealed retrograde penetration of impulses through the contralateral bundle "linking phenomenon." In this brief article, we present two patients with basal complete LBBB in whom ablating the right bundle unmasked the actual antegrade conduction capabilities of the left bundle. These cases highlight intriguing overlap between electrophysiological concepts of complete block, linking, extremely slow, and concealed conduction.
Lesson Eleven Transient and intermittent left bundle branch block
Institute of Scientific and Technical Information of China (English)
鲁端; 王劲
2004-01-01
@@ In transient left bundle branch block,normal intraventricular conduction subsequently returns,if only1temporarily.The condition has also been called paroxysmal,unstable,or temporary left bundle branch block. Its etiology is similar to that of the stable variety2, with the great majority of the patients having ischemic or hypertensive heart disease or both. Transient bundle branch block may complicate acute myocardial infarction or may occur during attacks of angina. It may appear during an episode of congestive heart failure and disappear with improvement of the cardiac status. Most patients eventually develop permanent block. Occasionally,however, the patient may revert to normal conduction even years after consistently demonstrating the block.
MYOCARDIAL DEFORMATION AND COMPLETE LEFT BUNDLE BRANCH BLOCK
Directory of Open Access Journals (Sweden)
E. N. Pavlyukova
2015-12-01
Full Text Available Tissue Doppler imaging is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular systolic and diastolic function. Over the last 10 years, myocardial deformation imaging has become possible initially with tissue Doppler , and more recently with myocardial speckle-tracking using 2D echocardiography. Unlike simple tissue velocity measurements, deformation measurements are specific for the region of interest. Strain rate or strain measurements have been used as sensitive indicators for subclinical diseases, and it is the most widely used tool to assess mechanical dyssynchrony. Left bundle branch block is a frequent, etiologically heterogeneous, clinically hostile and diagnostically challenging entity. About 2% of patients underwent cardiac stress testing show stable or intermittent left bundle branch block. Presence of left bundle branch block is associated with a lower and slower diastolic coronary flow velocity especially during hyperemia. Stress echocardiography is the best option for the diagnosis of ischemic heart disease, albeit specificity and sensitivity reduce in patients with left bundle branch block in the territory of left anterior descending artery in presence of initial septum dyskinesia.
Cardiac pacing in left bundle branch/ bifascicular block patients
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Maddali Madan
2010-01-01
Full Text Available The primary concern in patients with bifascicular block is the increased risk of progression to complete heart block. Further, an additional first-degree A-V block in patients with bifascicular block or LBBB might increase the risk of block progression. Anesthesia, monitoring and surgical techniques can induce conduction defects and bradyarrhythmias in patients with pre-existing bundle branch block. In the setting of an acute MI, several different types of conduction disturbance may become manifest and complete heart block occurs usually in patients with acute myocardial infarction more commonly if there is pre-existing or new bundle branch block. The question that arises is whether it is necessary to insert a temporary pacing catheter in patients with bifascicular block undergoing anesthesia. It is important that an anesthesiologist should be aware of the indications for temporary cardiac pacing as well as the current recommendations for permanent pacing in patients with chronic bifascicular and trifascicular block. This article also highlights the recent guidelines for temporary transvenous pacing in the setting of acute MI and the different pacing modalities that are available for an anesthesiologist.
Left bundle branch block: a rare ECG manifestation of hyperkalemia
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Venkata Madhav M
2015-04-01
Full Text Available A 20-year-old female patient with chronic kidney disease was brought to our emergency medical department with symptoms of pain in chest and abdomen, vomitings. Laboratory testing revealed serum potassium 7.7 mEq/L, serum creatinine 9.1 mg/dL. Electrocardiogram (ECG showed left bundle branch block (LBBB pattern with left axis deviation, tall T waves and ST elevation. Among ECG alterations in hyperkalemia, LBBB is rare and is being reported in our case.
[Unstable angina pectoris in intermittent left bundle branch block].
Albert, S; Flury, G
1997-11-19
We present a case report of a 57 year old woman with recurrent chest pain, initially exclusively at exercise and later also at rest. This led to an emergency hospitalization for suspected myocardial infarction. As there were no enzymatic and electrocardiographic signs of acute infarction she was treated, as unstable angina pectoris. Coronary angiography revealed but a modest coronary atheromatosis without significant coronary stenosis. Therefore her symptoms were interpreted as primary manifestation of an intermittant Left Bundle Branch Block (LBBB) with changing heart-rate dependency. A majority of patients with LBBB and chest pain have a relevant Coronary Artery Disease (CAD). There is a small number of reports in literature about patients with intermittant LBBB without significant CAD but with both typical (exercise-induced) and atypical (at rest) chest pain. Special features of our case are presentation of LBBB as unstable angina, documentation of an intermittant LBBB with changing heart-rate dependency and heart-rate-dependent supranormal conduction in the left bundle branch. We review some important aspects of LBBB with regard to this case.
Frequency and prognosis of new bundle branch block induced by surgical aortic valve replacement.
Poels, T.T.; Houthuizen, P.; Garsse, L.A. van; Soliman Hamad, M.A.; Maessen, J.G.; Prinzen, F.W.; Straten, A.H. Van
2015-01-01
OBJECTIVES: Recently, transcatheter aortic valve implantation has been introduced, but one of its complications is left bundle branch block (LBBB), a conduction disturbance that has been associated with increased mortality. We investigated the incidence and fate of both right bundle branch block
Electrical remodelling in patients with iatrogenic left bundle branch block.
Engels, Elien B; Poels, Thomas T; Houthuizen, Patrick; de Jaegere, Peter P T; Maessen, Jos G; Vernooy, Kevin; Prinzen, Frits W
2016-12-01
Left bundle branch block (LBBB) is induced in approximately one-third of all transcatheter aortic valve implantation (TAVI) procedures. We investigated electrophysiological remodelling in patients with TAVI-induced LBBB. This retrospective study comprises 107 patients with initially narrow QRS complex of whom 40 did not and 67 did develop persistent LBBB after TAVI. 12-lead electrocardiograms (ECGs) taken before TAVI, within 24 hours ('acute'), and 1-12 months after TAVI ('chronic') were used to reconstruct vectorcardiograms. From these vectorcardiograms, QRS and T-wave area were calculated as comprehensive indices of depolarization and repolarization abnormalities, respectively. TAVI-induced LBBB resulted in significant acute depolarization and repolarization changes while further repolarization changes were observed with longer lasting LBBB. The amount of long-term repolarization changes (remodelling) was highly variable between patients. The change in T-wave area between acute and chronic LBBB ranged from +57% to - 77%. After dividing the LBBB cohort into tertiles based on the change in T-wave area, only baseline QRS area was larger in the tertile with no significant change in T-wave area. During longer lasting LBBB, the spatial vector gradient (SVG) changed orientation towards the direction of the QRS-vector, indicating that later-activated regions developed shorter action potential duration. This study in patients with TAVI-induced LBBB shows that repolarization changes develop within months after onset of LBBB, and that these changes are highly variable between individual patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For Permissions, please email: journals.permissions@oup.com.
Experimental investigation of the coolability of blocked hexagonal bundles
Energy Technology Data Exchange (ETDEWEB)
Hózer, Zoltán, E-mail: zoltan.hozer@energia.mta.hu; Nagy, Imre; Kunstár, Mihály; Szabó, Péter; Vér, Nóra; Farkas, Róbert; Trosztel, István; Vimi, András
2017-06-15
Highlights: • Experiments were performed with electrically heated hexagonal fuel bundles. • Coolability of ballooned VVER-440 type bundle was confirmed up to high blockage rate. • Pellet relocation effect causes delay in the cool-down of the bundle. • The bypass line does not prevent the reflood of ballooned fuel rods. - Abstract: The CODEX-COOL experimental series was carried out in order to evaluate the effect of ballooning and pellet relocation in hexagonal bundles on the coolability of fuel rods after a LOCA event. The effects of blockage geometry, coolant flowrate, initial temperature and axial profile were investigated. The experimental results confirmed that a VVER bundle up to 80% blockage rate remains coolable after a LOCA event under design basis conditions. The ballooned section creates some obstacles for the cooling water during reflood of the bundle, but this effect causes only a short delay in the cooling down of the hot fuel rods. The accumulation of fuel pellet debris in the ballooned volume results in a local power peak, which leads to further slowing down of quench front.
Hecke Transformations of Conformal Blocks in WZW Theory. I. KZB Equations for Non-trivial Bundles
Levin, A; Smirnov, A; Zotov, A
2012-01-01
We describe new families of the Knizhnik-Zamolodchikov-Bernard (KZB) equations related to the WZW-theory corresponding to the adjoint G-bundles over complex curves \\Sigma_{g,n} of genus g with n marked points. The bundles are defined by their characteristic classes - elements of H^2(\\Sigma_{g,n}, Z(G)), where Z(G) is a center of the simple complex Lie group G. The KZB equations are the horizontality condition for the projectively flat connection (the KZB connection) defined on the bundle of conformal blocks over the moduli space of curves. The space of conformal blocks has been known to be decomposed into a few sectors corresponding to the characteristic classes of the underlying bundles. The KZB connection preserves these sectors. In this paper we construct the connection explicitly and prove its flatness for elliptic curves with marked points. For the trivial bundles our construction provides the KZB connection proposed by Felder-Wieczerkowski.
Hecke Transformations of Conformal Blocks in WZW Theory. I. KZB Equations for Non-Trivial Bundles
Directory of Open Access Journals (Sweden)
Andrey M. Levin
2012-12-01
Full Text Available We describe new families of the Knizhnik-Zamolodchikov-Bernard (KZB equations related to the WZW-theory corresponding to the adjoint $G$-bundles of different topological types over complex curves $Sigma_{g,n}$ of genus $g$ with $n$ marked points. The bundles are defined by their characteristic classes - elements of $H^2(Sigma_{g,n},mathcal{Z}(G$, where $mathcal{Z}(G$ is a center of the simple complex Lie group $G$. The KZB equations are the orizontality condition for the projectively flat connection (the KZB connectiondefined on the bundle of conformal blocks over the moduli space of curves. The space of conformal blocks has been known to be decomposedinto a few sectors corresponding to the characteristic classes of the underlying bundles. The KZB connection preserves these sectors.In this paper we construct the connection explicitly for elliptic curves with marked points and prove its flatness.
DEFF Research Database (Denmark)
Nielsen, Jonas Bille; Olesen, Morten Salling; Tangø, Mogens
2011-01-01
Aims P-wave morphology and PR interval have both been previously associated with atrial fibrillation (AF). We hypothesized that incomplete right bundle branch block (IRBBB) would be associated with early-onset lone AF. Methods and results We conducted a case-control study comparing electrocardiog......Aims P-wave morphology and PR interval have both been previously associated with atrial fibrillation (AF). We hypothesized that incomplete right bundle branch block (IRBBB) would be associated with early-onset lone AF. Methods and results We conducted a case-control study comparing...
Atypical right bundle brunch block and cardiac arrhythmias during exercise stress testing
Stevanovic, J.
2010-01-01
Background: Atypical right bundle brunch block may conceal potentially lethal arrhythmogenic canalopathy known as Brugada syndrome. This disorder is characterised by dynamic electrocardiographic patterns, ranging from type I to type II and type III. The typical arrhythmia is a rapid polymorphic
Left bundle branch block as a risk factor for progression to heart failure
DEFF Research Database (Denmark)
Zannad, Faiez; Huvelle, Etienne; Dickstein, Kenneth
2006-01-01
The prevalence of conduction disturbances, particularly left bundle branch block (LBBB), is strongly correlated with age and with the presence of cardiovascular disease. LBBB has been reported to affect approximately 25% of the heart failure (HF) population and it is likely that the deleterious r...
Kundu, Ria; Almasri, Hamzeh; Moza, Ankush; Ghose, Abhimanyu; Assaly, Ragheb
2013-01-01
We describe the management of a young patient who had experienced a cocaine overdose. The patient presented with altered mental status and seizures and subsequently developed a wide complex arrhythmia with a rare alternating bundle branch block pattern. Intravenous lipid emulsion was administered following initial resuscitation and endotracheal intubation, because conservative methods of treating the persistent cardiac arrhythmias failed.
Left bundle branch block (LBBB) masks changes due to hyperkalemia: a myth.
Kumar, Anil; Shah, Neel; Jesmajian, Stephen
2010-04-01
Left bundle branch block masks ischemic changes but not those due to electrolyte imbalance. Peaking of T waves, prolongation of PR interval, diminution/absence of P wave, and widening of QRS complex can still be appreciated if one carefully compares the baseline ECG to the presenting ECG. (c) 2010 Society of Hospital Medicine.
Atypical right bundle brunch block and cardiac arrhythmias during exercise stress testing
Stevanovic, J.
2010-01-01
Background: Atypical right bundle brunch block may conceal potentially lethal arrhythmogenic canalopathy known as Brugada syndrome. This disorder is characterised by dynamic electrocardiographic patterns, ranging from type I to type II and type III. The typical arrhythmia is a rapid polymorphic vent
Effects of fuel relocation on reflood in a partially-blocked rod bundle
Energy Technology Data Exchange (ETDEWEB)
Kim, Byoung Jae [School of Mechanical Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134 (Korea, Republic of); Kim, Jongrok; Kim, Kihwan; Bae, Sung Won [Thermal-Hydraulic Safety Research Division, Korea Atomic Energy Research Division, 111 Daedeok-daero, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Moon, Sang-Ki, E-mail: skmoon@kaeri.re.kr [Thermal-Hydraulic Safety Research Division, Korea Atomic Energy Research Division, 111 Daedeok-daero, Yuseong-gu, Daejeon 34057 (Korea, Republic of)
2017-02-15
Ballooning of the fuel rods has been an important issue, since it can influence the coolability of the rod bundle in a large-break loss-of-coolant accident (LBLOCA). Numerous past studies have investigated the effect of blockage geometry on the heat transfer in a partially blocked rod bundle. However, they did not consider the occurrence of fuel relocation and the corresponding effect on two-phase heat transfer. Some fragmented fuel particles located above the ballooned region may drop into the enlarged volume of the balloon. Accordingly, the fuel relocation brings in a local power increase in the ballooned region. The present study’s objective is to investigate the effect of the fuel relocation on the reflood under a LBLOCA condition. Toward this end, experiments were performed in a 5 × 5 partially-blocked rod bundle. Two power profiles were tested: one is a typical cosine shape and the other is the modified shape considering the effect of the fuel relocation. For a typical power shape, the peak temperature in the ballooned rods was lower than that in the intact rods. On the other hand, for the modified power shape, the peak temperature in the ballooned rods was higher than that in the intact rods. Numerical simulations were also performed using the MARS code. The tendencies of the peak clad temperatures were well predicted.
Role of electrophysiological study in patients with syncope and bundle branch block
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Neshat Nazari
2014-01-01
Full Text Available Background: The finding of bundle branch block (BBB in patients with syncope suggests that paroxysmal atrioventricular block (AVB or ventricular tachyarrhythmia (VT may be the cause of syncope. Guidelines for cardiac pacing and cardiac resynchronization therapy have been recommended to perform electrophysiological study (EPS for confirming main cause of syncope. Therefore, the aim of our study was to evaluate the role of EPS in patients with syncope and BBB. Materials and Methods: We evaluated 133 patients (mean age 63 ± 13.8 years with past history of syncope and BBB from April 2002 to December 2010 who referred to Arrhythmia clinic in two tertiary care centers. All patients underwent EPS on admission time. The frequency distributions of AVB and VT in patients were determined. Results: Left bundle branch block was diagnosed in 184 (82.1% patients. 133 of them had preserved left ventricular ejection fraction (LVEF ≥45% that in 91 (68.4% of those, EPS finding was normal. In 41 (30.8% patients AVB was reported. In 2 (1.5% patients VT and atrioventricular nodal reentrant tachycardia were seen. Coronary artery disease was more common in patients with AVB and abnormal EPS finding (P = 0.02. Conclusion: Ventricular tachyarrhythmia was a rare electrophysiological finding in those with syncope, bifascicular block, and preserved LVEF. Considering cost-effect benefit, pacemaker or implantable loop recorder implantation is suggested; however, EPS may not be necessary to perform before permanent pacemaker implantation.
Hybrid Bacterial Foraging and Particle Swarm Optimization for detecting Bundle Branch Block.
Kora, Padmavathi; Kalva, Sri Ramakrishna
2015-01-01
Abnormal cardiac beat identification is a key process in the detection of heart diseases. Our present study describes a procedure for the detection of left and right bundle branch block (LBBB and RBBB) Electrocardiogram (ECG) patterns. The electrical impulses that control the cardiac beat face difficulty in moving inside the heart. This problem is termed as bundle branch block (BBB). BBB makes it harder for the heart to pump blood effectively through the heart circulatory system. ECG feature extraction is a key process in detecting heart ailments. Our present study comes up with a hybrid method combining two heuristic optimization methods: Bacterial Forging Optimization (BFO) and Particle Swarm Optimization (PSO) for the feature selection of ECG signals. One of the major controlling forces of BFO algorithm is the chemotactic movement of a bacterium that models a test solution. The chemotaxis process of the BFO depends on random search directions which may lead to a delay in achieving the global optimum solution. The hybrid technique: Bacterial Forging-Particle Swarm Optimization (BFPSO) incorporates the concepts from BFO and PSO and it creates individuals in a new generation. This BFPSO method performs local search through the chemotactic movement of BFO and the global search over the entire search domain is accomplished by a PSO operator. The BFPSO feature values are given as the input for the Levenberg-Marquardt Neural Network classifier.
Akilan, A.; Nagasubramanian, V.; Chaudhry, A.; Reddy, D. Rajesh; Sudheer Reddy, D.; Usha Devi, R.; Tirupati, T.; Radhadevi, P. V.; Varadan, G.
2014-11-01
Block Adjustment is a technique for large area mapping for images obtained from different remote sensingsatellites.The challenge in this process is to handle huge number of satellite imageries from different sources with different resolution and accuracies at the system level. This paper explains a system with various tools and techniques to effectively handle the end-to-end chain in large area mapping and production with good level of automation and the provisions for intuitive analysis of final results in 3D and 2D environment. In addition, the interface for using open source ortho and DEM references viz., ETM, SRTM etc. and displaying ESRI shapes for the image foot-prints are explained. Rigorous theory, mathematical modelling, workflow automation and sophisticated software engineering tools are included to ensure high photogrammetric accuracy and productivity. Major building blocks like Georeferencing, Geo-capturing and Geo-Modelling tools included in the block adjustment solution are explained in this paper. To provide optimal bundle block adjustment solution with high precision results, the system has been optimized in many stages to exploit the full utilization of hardware resources. The robustness of the system is ensured by handling failure in automatic procedure and saving the process state in every stage for subsequent restoration from the point of interruption. The results obtained from various stages of the system are presented in the paper.
Corsini, G; Pette, R; Cardillo, A; Quintiliano, G; Di Donna, V; Malvezzi, A; Mascia, F; Correale, E
1989-01-01
The clinical, ECG and electrophysiological data of 37 patients (28 males and 9 females) with spontaneous intra-hisian block are reported. Of these patients, 11 had hypertensive heart disease and 5 had ischemic heart disease with previous myocardial infarction; in 21 patients, clinical signs of heart disease were not evident. In 18 patients, a single or recurrent episode of syncope had occurred. One patient had junctional rhythm and 36 sinus rhythm; among these, 12 patients presented PR greater than 200 msec (7 with a narrow and 5 with a wide QRS); 12 patients had a single or bilateral bundle branch block; 12 had a normal ECG. The electrophysiological study showed a split H-H1 in 22 patients, a wide His deflection (H greater than 25 msec) in 4 and HV greater than 65 msec with narrow QRS in 11. In 17 patients a more or less marked sinoatrial node and/or atrioventricular node dysfunction was present. Atrial pacing, performed in all, induced 2nd degree Mobitz 2 intra-hisian block in 9 patients. Ajmaline was used in 16 patients but induced a complete intra-hisian block in only one. In 28 patients a preventive pacemaker was implanted after electrophysiological study. During the follow-up (mean 25 months/pt.), 38% of the patients developed complete atrioventricular block. No recurrence of syncope occurred in the paced patients. Comparison of patients who developed atrioventricular block and those who maintained normal atrioventricular conduction did not show differences as far as heart disease, previous syncope, ECG pattern and results were concerned.(ABSTRACT TRUNCATED AT 250 WORDS)
Geometric Quality Assessment of Bundle Block Adjusted Mulit- Sensor Satellite Imageries
Ghosh, S.; Bhawani Kumar, P. S.; Radhadevi, P. V.; Srinivas, V.; Saibaba, J.; Varadan, G.
2014-11-01
The integration of multi-sensor earth observation data belonging to same area has become one of the most important input for resource mapping and management. Geometric error and fidelity between adjacent scenes affects large-area digital mosaic if the images/ scenes are processed independently. A block triangulation approach "Bundle Block Adjustment (BBA)" system has been developed at ADRIN for combined processing of multi-sensor, multi-resolution satellite imagery to achieve better geometric continuity. In this paper we present the evaluation results of BBA software along with performance assessment and operational use of products thus generated. The application evaluation deals with functional aspects of block-adjustment of satellite imagery consisting of data from multiple sources, i.e. AWiFs, LISS-3, LISS-4 and Cartosat-1 in various combinations as single block. It has provision for automatic generation of GCPs and tie-points using image metafile/ Rational Polynomial Coefficient's (RPC's) and ortho/ merged/ mosaicked products generation. The study is carried out with datasets covering different terrain types (ranging from high mountainous area, moderately undulating terrain, coastal plain, agriculture fields, urban area and water-body) across Indian subcontinent with varying block sizes and spatial reference systems. Geometric accuracy assessment is carried out to figure out error propagation at scene based ortho/ merged products as well as block level. The experimental results confirm that pixel tagging, geometric fidelity and feature continuity across adjacent scenes as well as for multiple sensors reduced to a great extent, due to the high redundancy. The results demonstrate that it is one of the most affective geometric corrections for generating large area digital mosaic over High mountainous terrain using high resolution good swath satellite imagery, like Cartosat-1, with minimum human intervention.
Heart Failure with Transient Left Bundle Branch Block in the Setting of Left Coronary Fistula
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Stephen P. Juraschek
2011-01-01
Full Text Available Coronary arterial fistulas are rare communications between vessels or chambers of the heart. Although cardiac symptoms associated with fistulas are well described, fistulas are seldom considered in the differential diagnosis of acute myocardial ischemia. We describe the case of a 64-year-old man who presented with left shoulder pain, signs of heart failure, and a new left bundle branch block (LBBB. Cardiac catheterization revealed a small left anterior descending (LAD-to-pulmonary artery (PA fistula. Diuresis led to subjective improvement of the patient's symptoms and within several days the LBBB resolved. We hypothesize that the coronary fistula in this patient contributed to transient ischemia of the LAD territory through a coronary steal mechanism. We elected to observe rather than repair the fistula, as his symptoms and ECG changes resolved with treatment of his heart failure.
Left bundle-branch block--pathophysiology, prognosis, and clinical management.
Francia, Pietro; Balla, Cristina; Paneni, Francesco; Volpe, Massimo
2007-03-01
Given its broad use as a screening tool, the electrocardiogram (ECG) has largely become one of the most common diagnostic tests performed in routine clinical practice. As a result, the finding of left bundle-branch block (LBBB) in the absence of a well-defined clinical setting has become relatively frequent and raises questions and often concerns. While in the absence of clinically detectable heart disease LBBB does not necessarily imply poor outcomes, physicians should be aware of the role of LBBB in stratifying risk of cardiovascular events and death in subjects with both ischemic and nonischemic heart disease. This paper reviews historical landmarks, pathophysiologic features, prognostic implications, and clinical management of LBBB in apparently healthy subjects and those with heart disease.
Detection of Bundle Branch Block using Adaptive Bacterial Foraging Optimization and Neural Network
Directory of Open Access Journals (Sweden)
Padmavthi Kora
2017-03-01
Full Text Available The medical practitioners analyze the electrical activity of the human heart so as to predict various ailments by studying the data collected from the Electrocardiogram (ECG. A Bundle Branch Block (BBB is a type of heart disease which occurs when there is an obstruction along the pathway of an electrical impulse. This abnormality makes the heart beat irregular as there is an obstruction in the branches of heart, this results in pulses to travel slower than the usual. Our current study involved is to diagnose this heart problem using Adaptive Bacterial Foraging Optimization (ABFO Algorithm. The Data collected from MIT/BIH arrhythmia BBB database applied to an ABFO Algorithm for obtaining best(important feature from each ECG beat. These features later fed to Levenberg Marquardt Neural Network (LMNN based classifier. The results show the proposed classification using ABFO is better than some recent algorithms reported in the literature.
van Gils, Lennart; Tchetche, Didier; Lhermusier, Thibault; Abawi, Masieh; Dumonteil, Nicolas; Rodriguez Olivares, R; de Nicolas, Javier Molina Martin; Stella, Pieter R.|info:eu-repo/dai/nl/304814717; Carrié, Didier; De Jaegere, Peter P.; Van Mieghem, Nicolas M.
2017-01-01
Background-Right bundle branch block is an established predictor for new conduction disturbances and need for a permanent pacemaker (PPM) after transcatheter aortic valve replacement. The aim of the study was to evaluate the absolute rates of transcatheter aortic valve replacement related PPM implan
Devarapally, Santhosh R; Arora, Sameer; Ahmad, Ali; Sood, Mike; El Sergany, Amaar; Sacchi, Terrence; Saul, Barry; Gaglani, Rahul; Heitner, John
2016-10-01
Right ventricular (RV) failure has proven to be independently associated with adverse outcomes. Electrocardiographic parameters assessing RV function are largely unknown, making echocardiography the first line for RV function assessment. It is however, limited by geometrical assumptions and is inferior to cardiac magnetic resonance imaging (CMRI) which is widely regarded as the most accurate tool for assessing RV function. We seek to determine the correlation of ECG parameters of right bundle branch block (RBBB) with RV ejection fraction (EF) and RV dimensions using the CMRI. QRS duration, R amplitude and R' duration were obtained from precordial lead V1; S duration and amplitude were obtained from lead I and AVL. RV systolic dysfunction was defined as RV EF diagrams between individual CMRI parameters and ECG parameters were done using medcalc for windows, version 12.5. Sensitivity, specificity and area under the curve (AUC) were calculated. RV systolic dysfunction group was found to have larger RV end systolic volumes (90±42 vs. 59±40 mL, P=0.02). ECG evaluation of RV dysfunction group revealed longer R' duration (103±22 vs. 84±18 msec, P=0.005) as compared to the control group. The specificity of R' duration >100 msec to detect RV systolic dysfunction was found to be 93%. R' duration was found to have an inverse correlation with RV EF (r=-0.49, P=0.007). Larger RV end systolic volumes seen with RV dysfunction can affect the latter part of right bundle branch leading to prolonged R' duration. We here found prolonged R' duration in lead V1 to have a highly specific inverse correlation to RV systolic function. ECG can be used as an inexpensive tool for RV function assessment and should be used alongside echocardiography to evaluate RV dysfunction when CMRI is not available.
Bundle Block Adjustment of Airborne Three-Line Array Imagery Based on Rotation Angles
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Yongjun Zhang
2014-05-01
Full Text Available In the midst of the rapid developments in electronic instruments and remote sensing technologies, airborne three-line array sensors and their applications are being widely promoted and plentiful research related to data processing and high precision geo-referencing technologies is under way. The exterior orientation parameters (EOPs, which are measured by the integrated positioning and orientation system (POS of airborne three-line sensors, however, have inevitable systematic errors, so the level of precision of direct geo-referencing is not sufficiently accurate for surveying and mapping applications. Consequently, a few ground control points are necessary to refine the exterior orientation parameters, and this paper will discuss bundle block adjustment models based on the systematic error compensation and the orientation image, considering the principle of an image sensor and the characteristics of the integrated POS. Unlike the models available in the literature, which mainly use a quaternion to represent the rotation matrix of exterior orientation, three rotation angles are directly used in order to effectively model and eliminate the systematic errors of the POS observations. Very good experimental results have been achieved with several real datasets that verify the correctness and effectiveness of the proposed adjustment models.
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Iwasaki,Jun
2009-02-01
Full Text Available
There is little information available concerning the influence of right bundle branch block (RBBB on the prognosis of patients with inferior myocardial infarction (MI. In this study we evaluated the influence of RBBB on the short-term prognosis of patients with inferior MI. Our study subjects were 1,265 hospitalized patients with Q wave MI. Patients were divided into 4 groups based on the presence or absence of RBBB and on the location of the infarction. RBBB was classified into 4 categories according to the timing of its appearance and its duration as new permanent, transient, old and age indeterminate. In-hospital death and pulmonary congestion were observed more frequently in patients with RBBB than in those without RBBB. Moreover, in inferior MI as in anterior MI, in-hospital death and pulmonary congestion occurred more frequently in new permanent RBBB patients than in patients with other types of RBBB. Multivariate regression analysis reveals that new permanent RBBB was a strong independent predictor for an adverse short-term prognosis in patients with inferior MI, as well as in patients with anterior MI. New permanent RBBB during inferior MI is a strong independent predictor for increased in-hospital mortality, regardless of the infarction location.
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Falcao, Andrea; Chalela, William; Giorgi, Maria Clementina; Imada, Rodrigo; Soares Junior, Jose; Do Val, Renata; Oliveira, Marco Antonio; Izaki, Marisa; Kalil Filho, Roberto; Meneghetti, Jose C., E-mail: andrea.falcao@incor.usp.br [Universidade de Sao Paulo (InCor/USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Instituto do Coracao
2015-11-15
Objectives: Perfusion abnormalities are frequently seen in Single Photon Emission Computed Tomography (SPECT) when a left bundle branch block is present. A few studies have shown decreased coronary flow reserve in the left anterior descending territory, regardless of the presence of coronary artery disease. Objective: we sought to investigate rubidium-82 ({sup 82}Rb) positron emission tomography imaging in the assessment of myocardial blood flow and coronary flow reserve in patients with left bundle branch block. Methods: thirty-eight patients with left bundle branch block (GI), median age 63.5 years, 22 (58%) female, 12 with coronary artery disease (≥70%; GI-A) and 26 with no evidence of significant coronary artery disease (GI-B), underwent rest-dipyridamole stress {sup 82}Rb-positron emission tomography with absolute quantitative flow measurements using Cedars-Sinai software (mL/min/g). The relative myocardial perfusion and left ventricular ejection fraction were assessed in 17 segments. These parameters were compared with those obtained from 30 patients with normal {sup 82}Rb-positron emission tomography studies and without left bundle branch block (GII). Results: stress myocardial blood flow and coronary flow reserve were significantly lower in GI than in GII (p>0.05). The comparison of coronary flow reserve between GI-A and GI-B showed that it was different from the global coronary flow reserve (p<0.05) and the stress flow was significantly lower in the anterior than in the septal wall for both groups. Perfusion abnormalities were more prevalent in GI-A (p=0.06) and the left ventricular ejection fraction was not different between GI-A and GI-B, whereas it was lower in GI than in GII (p<0.001). Conclusion: the data confirm that patients with left bundle branch block had decreased myocardial blood flow and coronary flow reserve and coronary flow reserve assessed by {sup 82}Rb-positron emission tomography imaging may be useful in identifying coronary artery
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Grand, Johannes; Thomsen, Jakob Hartvig; Kjærgaard, Jesper
2016-01-01
This study reports the prevalence and prognostic impact of right bundle branch block (RBBB) and left bundle branch block (LBBB) in the admission electrocardiogram (ECG) of comatose survivors of out-of-hospital cardiac arrest (OHCA). The present study is part of the predefined electrocardiographic...... substudy of the prospective randomized target temperature management trial, which found no benefit of targeting 33°C over 36°C in terms of outcome. Six-hundred eighty-two patients were included in the substudy. An admission ECG, which defined the present study population, was available in 602 patients (88...... was directly associated with higher mortality and independently associated with higher odds of unfavorable neurologic outcome. RBBB is seemingly an early indicator of an unfavorable prognosis after OHCA....
Usefulness of Dipyridamole Myocardial Perfusion SPECT in Patients with Left Bundle Branch Block
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Naser Aslanabadi
2006-08-01
Full Text Available Background: Diagnosis of coronary artery disease (CAD in patients with left bundle branch block (LBBB is considered as a challenge in cardiology due to the low accuracy of noninvasive methods such as basal and stress electrocardiography (ECG. This diagnostic challenge can be reduced but not eliminated using dipyridamole as a stress method instead of exercise. The aim of this study was to assess the diagnostic value of dipyridamole stress Tc-99m Sestamibi single photon emission computed tomography (SPECT myocardial perfusion imaging in patients with complete LBBB. Methods: We studied 40 patients with permanent and complete LBBB using Tc-99m Sestamibi SPECT and dipyridamole stress to evaluate CAD. Perfusion defect was considered fixed when there was no difference between rest and stress score, while reversible defect was defined as a segment with higher score on stress images. All patients underwent coronary angiography. Results: Eleven patients (27.5% had normal myocardial perfusion SPECT and 29 patients (72.5% had reversible perfusion defects. Angiography was positive in 30 patients, while 10 cases showed normal angiography. The sensitivity, specificity, positive predict value and negative predict value of our study for detecting >50% coronary stenosis was 86.6%, 70%, 89% and 64% respectively. Conclusion: We found 33 (82.5% patients with concordant angiography and myocardial perfusion SPECT results (p=0.002. Angiography was positive in 90% of patients with reversible perfusion defects on myocardial perfusion SPECT. In summary, Tc-99m Sestamibi SPECT in patients with LBBB showed high accuracy (82.5% in detecting >50% coronary stenosis.
Circumferential myocardial strain in cardiomyopathy with and without left bundle branch block
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Zimetbaum Peter J
2010-01-01
Full Text Available Abstract Background Cardiac resynchronization therapy (CRT has been shown to decrease mortality in 60-70% of advanced heart failure patients with left bundle branch block (LBBB and QRS duration > 120 ms. There have been intense efforts to find reproducible non-invasive parameters to predict CRT response. We hypothesized that different left ventricular contraction patterns may exist in LBBB patients with depressed systolic function and applied tagged cardiovascular magnetic resonance (CMR to assess circumferential strain in this population. Methods We determined myocardial circumferential strain at the basal, mid, and apical ventricular level in 35 subjects (10 with ischemic cardiomyopathy, 15 with non-ischemic cardiomyopathy, and 10 healthy controls. Patterns of circumferential strain were analyzed. Time to peak systolic circumferential strain in each of the 6 segments in all three ventricular slices and the standard deviation of time to peak strain in the basal and mid ventricular slices were determined. Results Dyskinesis of the anterior septum and the inferior septum in at least two ventricular levels was seen in 50% (5 out of 10 of LBBB patients while 30% had isolated dyskinesis of the anteroseptum, and 20% had no dyskinesis in any segments, similar to all of the non-LBBB patients and healthy controls. Peak circumferential strain shortening was significantly reduced in all cardiomyopathy patients at the mid-ventricular level (LBBB 9 ± 6%, non-LBBB 10 ± 4% vs. healthy 19 ± 4%; both p Conclusions Septal dyskinesis exists in some patients with LBBB. Myocardial circumferential strain analysis enables detailed characterization of contraction patterns, strengths, and timing in cardiomyopathy patients with and without LBBB.
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Estêvan Vieira Cabeda
2015-01-01
Full Text Available AbstractBackground:Functional tests have limited accuracy for identifying myocardial ischemia in patients with left bundle branch block (LBBB.Objective:To assess the diagnostic accuracy of dipyridamole-stress myocardial computed tomography perfusion (CTP by 320-detector CT in patients with LBBB using invasive quantitative coronary angiography (QCA (stenosis ≥ 70% as reference; to investigate the advantage of adding CTP to coronary computed tomography angiography (CTA and compare the results with those of single photon emission computed tomography (SPECT myocardial perfusion scintigraphy.Methods:Thirty patients with LBBB who had undergone SPECT for the investigation of coronary artery disease were referred for stress tomography. Independent examiners performed per-patient and per-coronary territory assessments. All patients gave written informed consent to participate in the study that was approved by the institution’s ethics committee.Results:The patients’ mean age was 62 ± 10 years. The mean dose of radiation for the tomography protocol was 9.3 ± 4.6 mSv. With regard to CTP, the per-patient values for sensitivity, specificity, positive and negative predictive values, and accuracy were 86%, 81%, 80%, 87%, and 83%, respectively (p = 0.001. The per-territory values were 63%, 86%, 65%, 84%, and 79%, respectively (p < 0.001. In both analyses, the addition of CTP to CTA achieved higher diagnostic accuracy for detecting myocardial ischemia than SPECT (p < 0.001.Conclusion:The use of the stress tomography protocol is feasible and has good diagnostic accuracy for assessing myocardial ischemia in patients with LBBB.
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Matthias Lange
Full Text Available False tendons (FTs are fibrous or fibromuscular bands that can be found in both the normal and abnormal human heart in various anatomical forms depending on their attachment points, tissue types, and geometrical properties. While FTs are widely considered to affect the function of the heart, their specific roles remain largely unclear and unexplored. In this paper, we present an in silico study of the ventricular activation time of the human heart in the presence of FTs. This study presents the first computational model of the human heart that includes a FT, Purkinje network, and papillary muscles. Based on this model, we perform simulations to investigate the effect of different types of FTs on hearts with the electrical conduction abnormality of a left bundle branch block (LBBB. We employ a virtual population of 70 human hearts derived from a statistical atlas, and run a total of 560 simulations to assess ventricular activation time with different FT configurations. The obtained results indicate that, in the presence of a LBBB, the FT reduces the total activation time that is abnormally augmented due to a branch block, to such an extent that surgical implant of cardiac resynchronisation devices might not be recommended by international guidelines. Specifically, the simulation results show that FTs reduce the QRS duration at least 10 ms in 80% of hearts, and up to 45 ms for FTs connecting to the ventricular free wall, suggesting a significant reduction of cardiovascular mortality risk. In further simulation studies we show the reduction in the QRS duration is more sensitive to the shape of the heart then the size of the heart or the exact location of the FT. Finally, the model suggests that FTs may contribute to reducing the activation time difference between the left and right ventricles from 12 ms to 4 ms. We conclude that FTs may provide an alternative conduction pathway that compensates for the propagation delay caused by the LBBB. Further
Siliste, Calin; Suran, Maria-Claudia-Berenice; Margulescu, Andrei-Dumitru; Vinereanu, Dragos
2015-03-01
We present a case of near-normalization of the QRS by septal pacing in a patient with dual-chamber pacemaker and underlying complete right bundle branch block and first degree atrioventricular block. The right ventricular mechanical synchronization suggested by the ECG was validated as such by strain echo. To the best of our knowledge, this is the first time it has been shown that the narrowing of the QRS corresponds to mechanical synchronization in a case of this seldom-recognized phenomenon.
van Gils, Lennart; Tchetche, Didier; Lhermusier, Thibault; Abawi, Masieh; Dumonteil, Nicolas; Rodriguez Olivares, Ramón; Molina-Martin de Nicolas, Javier; Stella, Pieter R; Carrié, Didier; De Jaegere, Peter P; Van Mieghem, Nicolas M
2017-03-03
Right bundle branch block is an established predictor for new conduction disturbances and need for a permanent pacemaker (PPM) after transcatheter aortic valve replacement. The aim of the study was to evaluate the absolute rates of transcatheter aortic valve replacement related PPM implantations in patients with pre-existent right bundle branch block and categorize for different transcatheter heart valves. We pooled data on 306 transcatheter aortic valve replacement patients from 4 high-volume centers in Europe and selected those with right bundle branch block at baseline without a previously implanted PPM. Logistic regression was used to evaluate whether PPM rate differed among transcatheter heart valves after adjustment for confounders. Mean age was 83±7 years and 63% were male. Median Society of Thoracic Surgeons score was 6.3 (interquartile range, 4.1-10.2). The following transcatheter valve designs were used: Medtronic CoreValve (n=130; Medtronic, Minneapolis, MN); Edwards Sapien XT (ES-XT; n=124) and Edwards Sapien 3 (ES-3; n=32; Edwards Lifesciences, Irvine, CA); and Boston Scientific Lotus (n=20; Boston Scientific Corporation, Marlborough, MA). Overall permanent pacemaker implantation rate post-transcatheter aortic valve replacement was 41%, and per valve design: 75% with Lotus, 46% with CoreValve, 32% with ES-XT, and 34% with ES-3. The indication for PPM implantation was total atrioventricular block in 98% of the cases. Lotus was associated with a higher PPM rate than all other valves. PPM rate did not differ between ES-XT and ES-3. Ventricular paced rhythm at 30-day and 1-year follow-up was present in 81% at 89%, respectively. Right bundle branch block at baseline is associated with a high incidence of PPM implantation for all transcatheter heart valves. PPM rate was highest for Lotus and lowest for ES-XT and ES-3. Pacemaker dependency remained high during follow-up. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by
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Nathan S. Anderson
2014-01-01
Full Text Available Exercise induced bundle branch block is a rare observation in exercise testing, accounting for 0.5 percent of exercise tests. The best treatment of this condition and its association with coronary disease remain unclear. We describe a case associated with normal coronary arteries which was successfully treated with exercise training. While this treatment has been used previously, our case has a longer followup than previously reported and demonstrates that the treatment is not durable in the absence of continued exercise.
Institute of Scientific and Technical Information of China (English)
Ju-fang CHI; Hang-yuan GUO; Long-bin LIU
2009-01-01
@@ Left bundle branch block (LBBB), traditionally viewed as an electrophysiologic abnormality, is increas-ingly recognized for its effects on hemodynamics and patient's prognosis[1]. Exercise nuclear studies frequently show reversible perfusion defects in the absence of ob-structive coronary artery disease[2] and some patients with intermittent LBBB develop angina coincident with the onset of LBBB[3]. We report a case of intermittent LBBB with abnormal stress technetium 99mTc single-pho-ton emission computed tomography (SPECT) study and normal coronary artery angiography.
Zheng, Maoteng; Zhang, Yongjun; Zhou, Shunping; Zhu, Junfeng; Xiong, Xiaodong
2016-07-01
In recent years, new platforms and sensors in photogrammetry, remote sensing and computer vision areas have become available, such as Unmanned Aircraft Vehicles (UAV), oblique camera systems, common digital cameras and even mobile phone cameras. Images collected by all these kinds of sensors could be used as remote sensing data sources. These sensors can obtain large-scale remote sensing data which consist of a great number of images. Bundle block adjustment of large-scale data with conventional algorithm is very time and space (memory) consuming due to the super large normal matrix arising from large-scale data. In this paper, an efficient Block-based Sparse Matrix Compression (BSMC) method combined with the Preconditioned Conjugate Gradient (PCG) algorithm is chosen to develop a stable and efficient bundle block adjustment system in order to deal with the large-scale remote sensing data. The main contribution of this work is the BSMC-based PCG algorithm which is more efficient in time and memory than the traditional algorithm without compromising the accuracy. Totally 8 datasets of real data are used to test our proposed method. Preliminary results have shown that the BSMC method can efficiently decrease the time and memory requirement of large-scale data.
Befeler, B; Castellanos, A; Aranda, J; Gutierrez, R; Lazzara, R
1976-02-01
Intracardiac electrophysiological studies were performed in two patients with a documented history of repetitive supraventricular tachyarrhythmias. Case 1, with short PR interval and narrow QRS complexes had a short AH interval and intermittent right bundle-branch block. Thus the short PR wide QRS syndrome is not always a result of the Wolff-Parkinson-White syndrome but can also be seen in the Lown-Ganong-Levine syndrome coexisting with bundle-branch block. Case 2, with normal PR and AH at the lower limits of normal, showed the dual pathway response to atrial pacing that can occur in patients with Lown-Ganong-Levine syndrome. He also had tachycardia-dependent right bundle-branch block and left posterior hemiblock. Therefore, neither the short PR interval nor the narrow QRS complexes characterized these forms of pre-excitation. The constant features were, from the clinical viewpoint, the occurrence of repetitive supraventricular tachyarrhythmias, and electrophysiologically the abnormal response to atrial stimulation.
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Nakagawa,Masahiro
1979-10-01
Full Text Available Vectorcardiogram (VCG recorded by both the Frank and Kimura systems were examined in 45 patients with complete right bundle branch block (RBBB and left axis deviation (LAD to investigate the relationship seen on electrocardiogram (ECG between RBBB with LAD and bilateral bundle. The sample included: 13 cases of type SI, SII, SIII, SaVF; 21 cases of type SI, SII, SIII, aVF; and 11 cases of types SI, SII, SIII. VCG recorded by the Frank system were classified into seven types according to the QRS loop pattern on the frontal plane and into three types according to the horizontal plane. The main findings were: (a In the Frank system the QRS loop in the frontal plane showed a variety of patterns in RBBB with LAD. (b On VCG of complete RBBB judged complicated by a left anterior hemiblock by the Frank system, the main portion of the QRS loop extended to the left superior or merely to the left in the frontal plane. The direction of rotation and position on the horizontal plane were not consistent. (c The results of this study suggest the usefulness of the Kimura system as an auxiliary diagnostic technique.
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Biton, Yitschak; Kutyifa, Valentina; Cygankiewicz, Iwona
2016-01-01
BACKGROUND: There are conflicting data regarding the efficacy of cardiac resynchronization therapy (CRT) in patients with heart failure (HF) and without left bundle branch block. METHODS AND RESULTS: We evaluated the long-term clinical outcomes of 537 non-left bundle branch block patients with mi...... shorter QRS was associated with a significantly increased risk with CRT-D relative to implantable cardioverter-defibrillator -only. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00180271, NCT01294449, and NCT02060110....
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Tatsumi Kazuhiro
2011-02-01
Full Text Available Abstract A 53-year-old man with depressed ejection fraction (EF of 35% and QRS width of 88 ms at rest was admitted to our institution with a complaint of exertional chest discomfort and dyspnea. During treadmill exercise, left bundle-branch block (LBBB with a QRS width of 152 ms occurred at a heart rate of 100 bpm. During LBBB, the patient showed significant mechanical dyssynchrony as evidenced by a two-dimensional speckle tracking radial strain of 260 ms (≥130 ms, defined as the time difference between anterior-septum and posterior wall. Five-month after carvedilol and candesartan administration, EF had improved to 49% and LBBB did not occur until a heart rate of 126 bpm was attained during treadmill exercise. It appears that pharmacological therapy may be useful for patients with heart failure and exercise-induced LBBB.
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Witt, Christoffer Tobias; Kronborg, Mads Brix; Nohr, Ellen Aagaard;
2016-01-01
PURPOSE: To assess the acute effect of triggered left ventricular pacing (tLVp) on left ventricular performance and contraction pattern in patients with heart failure, left bundle branch block (LBBB), and cardiac resynchronization therapy (CRT). METHODS: Twenty-three patients with pre-implant QRS...... conduction, tLVp, and BiV pacing and compared as paired data. Echocardiographic analysis was done blinded with respect to pacing mode. RESULTS: LVEF was significantly higher during BiV pacing (47 ± 11 %) compared with intrinsic conduction (43 ± 13 %, P = 0.001) and tLVp (44 ± 13 %, P = 0.001), while......V pacing. CONCLUSIONS: The acute effect of tLVp on LV systolic function and contraction pattern is significantly lower than the effect of BiV pacing and not different from intrinsic conduction in patients with LBBB and CRT....
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Dou Jianhong; Xia Ling; Zhang Yu; Shou Guofa [Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027 (China); Wei Qing; Liu Feng; Crozier, Stuart [School of Information Technology and Electrical Engineering, University of Queensland, St Lucia, Brisbane, Queensland 4072 (Australia)], E-mail: xialing@zju.edu.cn
2009-01-21
Asynchronous electrical activation, induced by bundle branch block (BBB), can cause reduced ventricular function. However, the effects of BBB on the mechanical function of heart are difficult to assess experimentally. Many heart models have been developed to investigate cardiac properties during BBB but have mainly focused on the electrophysiological properties. To date, the mechanical function of BBB has not been well investigated. Based on a three-dimensional electromechanical canine heart model, the mechanical properties of complete left and right bundle branch block (LBBB and RBBB) were simulated. The anatomical model as well as the fiber orientations of a dog heart was reconstructed from magnetic resonance imaging (MRI) and diffusion tensor MRI (DT-MRI). Using the solutions of reaction-diffusion equations and with a strategy of parallel computation, the asynchronous excitation propagation and intraventricular conduction in BBB was simulated. The mechanics of myocardial tissues were computed with time-, sarcomere length-dependent uniaxial active stress initiated at the time of depolarization. The quantification of mechanical intra- and interventricular asynchrony of BBB was then investigated using the finite-element method with an eight-node isoparametric element. The simulation results show that (1) there exists inter- and intraventricular systolic dyssynchrony during BBB; (2) RBBB may have more mechanical synchrony and better systolic function of the left ventricle (LV) than LBBB; (3) the ventricles always move toward the early-activated ventricle; and (4) the septum experiences higher stress than left and right ventricular free walls in BBB. The simulation results validate clinical and experimental recordings of heart deformation and provide regional quantitative estimates of ventricular wall strain and stress. The present work suggests that an electromechanical heart model, incorporating real geometry and fiber orientations, may be helpful for better
Stengaard, Carsten; Sørensen, Christina Ankjær; Thygesen, Kristian; Bøtker, Hans Erik; Thuesen, Leif; Terkelsen, Christian Juhl
2013-01-01
Background: Immediate revascularization is beneficial in patients with presumed new-onset bundle branch block myocardial infarction (BBBMI). In the prehospital setting, it is a challenge to diagnose new-onset BBBMI and triage accordingly. Methods: ECG, final diagnosis, and mortality were assessed in a prehospital cohort of 4905 consecutive patients with suspected acute myocardial infarction (AMI). Bundle branch block (BBB) was defined as QRS duration ≥120 ms caused by delayed intraventricular conduction. Mortality and angiography data were obtained from the Central Office of Civil Registration and the Western Denmark Heart Registry. Definite diagnosis of AMI and the onset of BBB were determined by expert consensus. Patients were divided into four groups: with or without AMI and with or without BBB. Mortality was evaluated by Kaplan–Meier plots and compared using log-rank statistics. Results: AMI was diagnosed in 954 patients, of whom 118 had BBB. In 3951 patients without AMI, 436 had BBB. Patients with BBBMI were less often revascularized than patients with AMI without BBB (24 vs. 54%, p<0.001). BBBMI was categorized as new onset in 43 patients of whom two were triaged for acute angioplasty. One-year mortality was 47.2, 17.5, 20.8, and 8.6% (log-rank <0.001) in patients with BBBMI, patients with AMI without BBB, patients with BBB without AMI, and patients without AMI or BBB, respectively. Conclusions: Patients with BBBMI have a high mortality. Less than 25% undergo revascularization and only very few patients with new-onset BBBMI are transferred for urgent revascularization. Focus on improving triage and prehospital identification of high-risk patients with BBB and chest pain could improve outcome. PMID:24222828
Pappone, C; Rosanio, S; Oreto, G; Tocchi, M; Gulletta, S; Salvati, A; Dicandia, C; Santinelli, V; Mazzone, P; Veglia, F; Ding, J; Sallusti, L; Spinelli, J; Vicedomini, G
2000-07-01
Acute left ventricular pacing has been associated with hemodynamic improvement in patients with congestive heart failure and wide QRS complex. We hypothesized that pacing two left ventricular sites simultaneously would produce faster activation and better systolic function than single-site pacing. We selected 14 heart failure patients (NYHA functional class III or IV) in normal sinus rhythm with left bundle branch block and QRS > 150 ms. An 8F dual micromanometer catheter was placed in the aorta for measuring +dP/dt (mmHg/s), aortic pulse pressure (mmHg), and end-diastolic pressure (mmHg). Pacing leads were positioned via coronary veins at the posterior base and lateral wall. Patients were acutely paced VDD at the posterior base, lateral wall, and both sites (dual-site) with 5 atrioventricular delays (from 8 ms to PR -30 ms). Pacing sequences were executed in randomized order using a custom external computer (FlexStim, Guidant CRM). Dual-site pacing increased peak +dP/dt significantly more than posterior base and lateral wall pacing. Dual-site and posterior base pacing raised aortic pulse pressure significantly more than lateral wall pacing. Dual-site pacing shortened QRS duration by 22 %, whereas posterior base and lateral wall pacing increased it by 2 and 12%, respectively (p = 0.006). In heart failure patients with left bundle branch block, dual-site pacing improves systolic function more than single-site stimulation. Improved ventricular activation synchrony, expressed by paced QRS narrowing, may account for the additional benefit of dual- vs single-site pacing in enhancing contractility. This novel approach deserves consideration for future heart failure pacing studies.
Dou, Jianhong; Xia, Ling; Zhang, Yu; Shou, Guofa; Wei, Qing; Liu, Feng; Crozier, Stuart
2009-01-01
Asynchronous electrical activation, induced by bundle branch block (BBB), can cause reduced ventricular function. However, the effects of BBB on the mechanical function of heart are difficult to assess experimentally. Many heart models have been developed to investigate cardiac properties during BBB but have mainly focused on the electrophysiological properties. To date, the mechanical function of BBB has not been well investigated. Based on a three-dimensional electromechanical canine heart model, the mechanical properties of complete left and right bundle branch block (LBBB and RBBB) were simulated. The anatomical model as well as the fiber orientations of a dog heart was reconstructed from magnetic resonance imaging (MRI) and diffusion tensor MRI (DT-MRI). Using the solutions of reaction-diffusion equations and with a strategy of parallel computation, the asynchronous excitation propagation and intraventricular conduction in BBB was simulated. The mechanics of myocardial tissues were computed with time-, sarcomere length-dependent uniaxial active stress initiated at the time of depolarization. The quantification of mechanical intra- and interventricular asynchrony of BBB was then investigated using the finite-element method with an eight-node isoparametric element. The simulation results show that (1) there exists inter- and intraventricular systolic dyssynchrony during BBB; (2) RBBB may have more mechanical synchrony and better systolic function of the left ventricle (LV) than LBBB; (3) the ventricles always move toward the early-activated ventricle; and (4) the septum experiences higher stress than left and right ventricular free walls in BBB. The simulation results validate clinical and experimental recordings of heart deformation and provide regional quantitative estimates of ventricular wall strain and stress. The present work suggests that an electromechanical heart model, incorporating real geometry and fiber orientations, may be helpful for better
DEFF Research Database (Denmark)
Stephenson, Kent; Skali, Hicham; McMurray, John J V;
2006-01-01
BACKGROUND: In survivors of myocardial infarction (MI), new left bundle branch block (LBBB) is associated with adverse outcomes, but its impact is not well described in post-MI patients with left ventricular (LV) systolic dysfunction and/or heart failure (HF). OBJECTIVES: The aim of this study wa...
Proline Scan of the hERG Channel S6 Helix Reveals the Location of the Intracellular Pore Gate
Thouta, Samrat; Sokolov, Stanislav; Abe, Yuki; Clark, Sheldon J.; Cheng, Yen M.; Claydon, Tom W.
2014-01-01
In Shaker-like channels, the activation gate is formed at the bundle crossing by the convergence of the inner S6 helices near a conserved proline-valine-proline motif, which introduces a kink that allows for electromechanical coupling with voltage sensor motions via the S4-S5 linker. Human ether-a-go-go-related gene (hERG) channels lack the proline-valine-proline motif and the location of the intracellular pore gate and how it is coupled to S4 movement is less clear. Here, we show that proline substitutions within the S6 of hERG perturbed pore gate closure, trapping channels in the open state. Performing a proline scan of the inner S6 helix, from Ile655 to Tyr667 revealed that gate perturbation occurred with proximal (I655P-Q664P), but not distal (R665P-Y667P) substitutions, suggesting that Gln664 marks the position of the intracellular gate in hERG channels. Using voltage-clamp fluorimetry and gating current analysis, we demonstrate that proline substitutions trap the activation gate open by disrupting the coupling between the voltage-sensing unit and the pore of the channel. We characterize voltage sensor movement in one such trapped-open mutant channel and demonstrate the kinetics of what we interpret to be intrinsic hERG voltage sensor movement. PMID:24606930
Institute of Scientific and Technical Information of China (English)
WANG Mu-xuan; Andrew D.Michaels; MA Hong; WU Gui-fu; GU Jing-li; LI Li; LU Kun; YANG Da; CHEN Long; ZHANG Xi; LUO Fu-tian
2012-01-01
Background Incomplete right bundle branch block (ICRBBB) is commonly associated with atrial septal defect (ASD),but lacks sufficient diagnostic test characteristics.An abnormal T wave is also often observed in ASD,with horizontal or inverted displacement of the proximal T wave limb in the right precordial leads,termed "defective T wave" (DTW).Methods We examined the diagnostic test characteristics of combining ICRBBB with DTVV as a new index to diagnose ASD.A total of 132 consecutive patients with ASD and 132 cases of age/gender-matched controls without ASD were enrolled.Results Sensitivities of DTW,ICRBBB,and both were 87.1％-87.9％.Specificities were 97.0％,96.2％,and 100％,respectively.Positive predictive values were 1.3％,1.1％,and 100.0％ respectively,while negative predictive values were 99.9％ for each.Conclusion Combining ICRBBB with DTW in electrocardiogram (ECG) as a new index significantly increased the specificity and positive predictive values while maintaining a high sensitivity in diagnosing ASD.
Ten Cate, T J F; Kelder, J C; Plokker, H W M; Verzijlbergen, J F; van Hemel, N M
2013-03-01
Myocardial perfusion SPECT (MPS) is frequently used for cardiovascular risk stratification. The significance of MPS in patients with abnormal electrical ventricular activation is often questionable. This review assesses the value of MPS for risk stratification of patients with intrinsic left bundle branch block or that due to right ventricular apical pacing. We reviewed the literature by a search of the MEDLINE database (January 1980 to September 2010). The terms prognosis or prognostic value were combined with SPECT and LBBB or pacing or pacemakers. MPS was categorised as low and high risk according to the original definitions. We identified 11 studies suitable for review. A low-risk MPS is associated with a low risk of cardiac events whereas high-risk MPS carries a 4.8-fold increased risk, 95% CI [3.2 - 7.2] (p < 0.0001). Despite secondary prevention and an improved medical and interventional care, these figures have hardly changed over time. A low-risk MPS permits a policy of watchful waiting whereas a high-risk MPS requires further analysis and treatment. The persistent high cardiac death and acute myocardial infarction rate after a high-risk MPS suggest that the current management of these patients does not suffice and needs reconsideration.
ten Cate, Tim J F; Kelder, Johannes C; Plokker, Herbert W M; Verzijlbergen, J Fred; van Hemel, Norbert M
2010-04-01
The value of myocardial perfusion SPECT (MPS) for patients with left bundle branch block (LBBB) or right ventricular apical (RVA) pacing seems reduced. The prognosis of patients with only abnormal activation related perfusion defects (AARD) due to LBBB or RVA-pacing is similar to those with a normal MPS. We assessed the prognostic value of MPS in patients with LBBB or RVA pacing. Patients with LBBB or RVA pacing referred for vasodilator stress MPS between April 2002 and January 2006 were analyzed. Group 1 are patients with normal MPS and MPS with AARD. Group 2 are patients with an MPS with a perfusion defect extending outside the AARD area. Events were cardiac death, acute myocardial infarction and coronary revascularization. In Group 1 (101 patients) 12 events and in Group 2 (96 patients) 45 events occurred during a mean follow-up of 2.6 +/- 1.5 years. The prognosis of Group 2 was significantly worse (49%) compared with Group 1 (91%). The annual cardiac death rate was 0.7%/year in Group 1 and 6.4%/year in Group 2 (P < .001). The prognosis of patients with LBBB was not different from those with RVA pacing. Group 2 had a significantly worse cardiac prognosis compared to Group 1. The annual cardiac death rate of <1% in Group 1 warrants a watchful waiting strategy, whereas the cardiac death rate in Group 2 warrants aggressive invasive coronary strategies.
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Marterer, Robert; Tschauner, Sebastian; Sorantin, Erich [Medical University of Graz, Division of Pediatric Radiology, Department of Radiology, Graz (Austria); Zeng, Hongchun [First Affiliated Hospital of Xinjiang Medical University, Department of Ultrasonography, Urumqi (China); Koestenberger, Martin [Medical University of Graz, Division of Pediatric Cardiology, Department of Pediatrics and Adolescent Medicine, Graz (Austria)
2015-12-15
Right ventricular (RV) function represents a prognostic marker in patients with corrected congenital heart disease. In up to 80 % of these patients, right branch bundle block (RBBB) exists and leads to asynchronous ventricular contraction. The aim of this retrospective study was to evaluate the change of RV performance parameters considering delayed RV end-systolic contraction. RV volumes of 33 patients were assessed twice: 1) not taking account of RBBB (group I), and 2) considering RBBB (group II). According to the RV ejection fraction (EF) for both groups, RV function was classified in different categories (>50 % = normal, 40-50 % = mildly-, 30-40 % = moderately-, <30 % = severely-reduced). The mean time difference between maximal systolic contraction of the septum and RV free wall was 90.7 ms ± 42.6. Consequently, RV end-systolic volume was significantly decreased in group II (p < 0.001). Accordingly, RV stroke volume and RV EF were significantly higher in group II (p < 0.001). There was also a significant change in the assessment of RV function (p < 0.02). RBBB induced delayed RV contraction can be detected at CMR. Ignoring the RV physiology in RBBB patients leads to a statistically significant underscoring of RV performance parameters. (orig.)
Yamasaki, Hiro; Lustgarten, Daniel; Cerkvenik, Jeffrey; Birnie, David; Gasparini, Maurizio; Lee, Kathy Lia-Fun; Sekiguchi, Yukio; Varma, Niraj; Lemke, Bernd; Starling, Randall C; Aonuma, Kazutaka
2017-08-01
Adaptive cardiac resynchronization therapy (aCRT) is a dynamic optimization algorithm which paces only the left ventricle (LV) when atrio-ventricular (AV) conduction is normal, thus reducing right ventricular (RV) pacing. However, the impact of QRS duration on aCRT efficacy remains uncertain. We examined whether QRS duration impacts aCRT effectiveness in patients with left bundle branch block (LBBB) and preserved AV conduction. Randomized patients in the Adaptive CRT trial, which enrolled NYHA III/IV patients, were used in this analysis. Patients were randomized to receive aCRT or echo-optimized bi-ventricular CRT (control arm). Endpoints for this analysis were clinical composite score (CCS) at 6months post-implant and time to first heart failure (HF) hospitalization or death. Among the 199 patients with LBBB and normal AV intervals at baseline, 80 patients (40%) had a baseline moderately wide QRS of 120-150ms. In this subgroup, a greater proportion of aCRT patients had an improved CCS (79% vs. 50%) at 6months compared to the control group (p=0.03). There was also a trend toward a lower risk of death or HF hospitalization (hazard ratio: 0.53; 95% CI: 0.24-1.15; p=0.10) in the moderately wide QRS subgroup with aCRT compared to the control arm. In the wide QRS subgroup, the efficacy was comparable in both treatment arms. Adaptive CRT was associated with improved patient outcomes over echo-optimized bi-ventricular CRT in patients with preserved AV conduction, LBBB, and moderately wide QRS. The adaptive cardiac resynchronization therapy trial (ClinicalTrials.gov Identifier: NCT00980057) was sponsored by Medtronic plc, Mounds View, MN. Copyright © 2017 Elsevier B.V. All rights reserved.
Burgos, Paula Freitas Martins; Luna Filho, Bráulio; Costa, Francisco de Assis; Bombig, Maria Teresa Nogueira; de Souza, Dilma; Bianco, Henrique Tria; Oliveira Filho, Japy Angelini; Izar, Maria Cristina de Oliveira; Fonseca, Francisco Antonio Helfenstein; Póvoa, Rui
2017-01-01
Background Left ventricular hypertrophy (LVH) is an important risk factor for cardiovascular events, and its detection usually begins with an electrocardiogram (ECG). Objective To evaluate the impact of complete left bundle branch block (CLBBB) in hypertensive patients in the diagnostic performance of LVH by ECG. Methods A total of 2,240 hypertensive patients were studied. All of them were submitted to an ECG and an echocardiogram (ECHO). We evaluated the most frequently used electrocardiographic criteria for LVH diagnosis: Cornell voltage, Cornell voltage product, Sokolow-Lyon voltage, Sokolow-Lyon product, RaVL, RaVL+SV3, RV6/RV5 ratio, strain pattern, left atrial enlargement, and QT interval. LVH identification pattern was the left ventricular mass index (LVMI) obtained by ECHO in all participants. Results Mean age was 11.3 years ± 58.7 years, 684 (30.5%) were male and 1,556 (69.5%) were female. In patients without CLBBB, ECG sensitivity to the presence of LVH varied between 7.6 and 40.9%, and specificity varied between 70.2% and 99.2%. In participants with CLBBB, sensitivity to LVH varied between 11.9 and 95.2%, and specificity between 6.6 and 96.6%. Among the criteria with the best performance for LVH with CLBBB, Sokolow-Lyon, for a voltage of ≥ 3,0mV, stood out with a sensitivity of 22.2% (CI 95% 15.8 - 30.8) and specificity of 88.3% (CI 95% 77.8 - 94.2). Conclusion In hypertensive patients with CLBBB, the most often used criteria for the detection of LVH with ECG showed significant decrease in performance with regards to sensitivity and specificity. In this scenario, Sokolow-Lyon criteria with voltage ≥3,0mV presented the best performance. PMID:27992034
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Bockeria L. A.
2012-03-01
Full Text Available Patients with severe chronic heart failure (CHF often have such intraventricular conduction disturbances as left bundle branch block which show morphological and QRS-duration changes on ECG and result in evident intra- and interventricular dyssinchrony. Delayed left ventricular activation via interventricular septum results in evident asynchrony at the beginning of left and right ventricular contration. Diagnostic significance of ECG data increases in presence of CHF clinical signs, especially echocardiographic signs of myocardial dysfunction. EVEREST study analyzed the influence of QRS duration on number of hospital admissions and mortality in patients with CHF. The study included 2962 patients, 1614 of them had normal QRS duration – less than 120 ms, 1321 patients had increased QRS duration – more than 120 ms. 678 deaths occurred during followup period, 307 (18.7% of them were from group with normal QRS duration and 371 (28.1% – from group with increased QRS interval. Mortality rate due to cardiovascular causes was more significant in patients with increased QRS. In 3 months of follow-up the mortality rate was 21.1% in patients with increased QRS and 14.6% in patients with normal QRS. In 9.9 months of follow-up the rates were 41.6% and 32.4%, respectively. Different international studies showed that isolated right ventricular pacing resulted in prolongation of QRS complex and contributed to CHF progression. 2010 patients were randomized in MOST-study which aimed to compare dual chamber pacing and right ventricular pacing. Reduction of CHF symptoms was noted in the course of study in patients who underwent dual chamber pacing, while M.O. Sweeney et al. analyzed the results of treatment of 1339 patients with initially normal QRS duration. However the authors revealed a higher rate in group of right ventricular pacing which proved the higher rates of hospital admission for CHF and more frequent rates for atrial fibrillation occurrence
Saporito, Salvatore; van Assen, Hans C; Houthuizen, Patrick; Aben, Jean-Paul M M; Strik, Marc; van Middendorp, Lars B; Prinzen, Frits W; Mischi, Massimo
2016-10-01
To compare cine and tagged magnetic resonance imaging (MRI) for left ventricular dyssynchrony assessment in left bundle branch block (LBBB), using the time-to-peak contraction timing, and a novel approach based on cross-correlation. We evaluated a canine model dataset (n = 10) before (pre-LBBB) and after induction of isolated LBBB (post-LBBB). Multislice short-axis tagged and cine MRI images were acquired using a 1.5 T scanner. We computed contraction time maps by cross-correlation, based on the timing of radial wall motion and of circumferential strain. Finally, we estimated dyssynchrony as the standard deviation of the contraction time over the different regions of the myocardium. Induction of LBBB resulted in a significant increase in dyssynchrony (cine: 13.0 ± 3.9 msec for pre-LBBB, and 26.4 ± 5.0 msec for post-LBBB, P = 0.005; tagged: 17.1 ± 5.0 msec at for pre-LBBB, and 27.9 ± 9.8 msec for post-LBBB, P = 0.007). Dyssynchrony assessed by cine and tagged MRI were in agreement (r = 0.73, P = 0.0003); differences were in the order of time difference between successive frames of 20 msec (bias: -2.9 msec; limit of agreement: 10.1 msec). Contraction time maps were derived; agreement was found in the contraction patterns derived from cine and tagged MRI (mean difference in contraction time per segment: 3.6 ± 13.7 msec). This study shows that the proposed method is able to quantify dyssynchrony after induced LBBB in an animal model. Cine-assessed dyssynchrony agreed with tagged-derived dyssynchrony, in terms of magnitude and spatial direction. J. MAGN. RESON. IMAGING 2016;44:956-963. © 2016 International Society for Magnetic Resonance in Medicine.
Arslan, Uğur; Balcioğlu, Serhat; Tavil, Yusuf; Ozdemir, Murat; Cengel, Atiye
2008-04-01
To investigate functional status of patients (Killip class), left ventricular contractility, angiographic anatomy and severity of coronary lesions in patients with and without right bundle branch block (RBBB) in the setting of anterior myocardial infarction (MI). Patients who admitted to coronary care unit with the diagnosis of acute anterior MI between 1999 and 2005 were retrospectively searched from our database. Out of 792 patients, 37 had RBBB (RBBB group) either at admission or in the course of anterior MI. Forty patients who developed no intraventricular conduction defect during the course of anterior MI with the same demographic characteristics were selected as the control group. Out of 37 patients, 30 had RBBB on admission and 7 developed RBBB in the course of acute MI. Left anterior descending artery (LAD) proximal lesion was more commonly detected in the RBBB group [23 (62.2%) vs. 11 (27.5%) patients, p=0.003]. Left ventricular ejection fraction was lower (33.0+/-4.2% vs 36.7+/-4.9%, p=0.003) and end-systolic volume was higher (84.1+/-24.9 ml vs 74.6+/-22.0 ml, p=0.012) in patients with RBBB. Number of patients with high Killip grade (III and IV) was more in the RBBB group [7 (18.9%) vs 3 (7.5%), RR: 1.75, %95 CI 0.92-3.32, p=0.14], and number of patients with Killip grade I was more in the control group [34 (85.0%) vs 22 (59.5%), p=0.012]. Besides mean Killip class was higher in the RBBB group (1.65+/-0.90 vs 1.25+/-0.67, p=0.03). Three patients (8.1%) in the RBBB group and 2 patients (5.0%) in the control group died during hospitalization (p=0.67). Left ventricular ejection fraction decreases and Killip grade increases in case of RBBB in the setting of acute anterior MI. Culprit lesion in patients with RBBB is more commonly a LAD proximal lesion and threatened myocardial tissue is larger in patients with RBBB.
Tu, Chung-Ming; Chu, Kai-Ming; Yang, Shin-Ping; Cheng, Shu-Mung; Wang, Wen-Been
2009-09-01
Trastuzumab (Herceptin) is well documented in reducing suffering and mortality from breast cancer. The clinically most important side effect of Herceptin is cardiotoxicity, which is reported in 2.6% to 4.5% of patients receiving trastuzumab alone and in as many as 27% of patients when trastuzumab is combined with an anthracycline in metastatic disease. We reported the case of a 50-year-old woman who presented to our emergency department (ED) because of chest pain and shortness of breath. On physical examination, holosystolic murmur over apex could be heard. Pulmonary and abdominal examinations were unremarkable. Twelve-lead electrocardiography showed sinus tachycardia and new onset of complete left bundle-branch block. Emergent transthoracic echocardiography revealed generalized hypokinesia of left ventricle and akinesia over interventricular septum and apex. She subsequently underwent immediate coronary angiography that revealed normal coronary angiography, and left ventriculogram revealed generalized hypokinesia with severe left ventricle dysfunction with ejection fraction of 33%. During right heart catheterization and endomyocardial biopsy, cardiac tamponade developed and was successfully relieved by pericardial window. She was discharged event-free 3 weeks later with conservative treatment. Although new onset of complete left bundle-branch block in a patient with chest pain may be acute coronary syndrome, careful review of medicine history is mandatory to avoid unnecessary procedure and complications.
Kusumoto, Saburo; Kawano, Hiroaki; Makita, Naomasa; Ichimaru, Shinichiro; Kaku, Takashi; Haruta, Daisuke; Hida, Ayumi; Sera, Nobuko; Imaizumi, Misa; Nakashima, Eiji; Maemura, Koji; Akahoshi, Masazumi
2014-06-01
We investigated the clinical course of complete right bundle branch block (RBBB) or RBBB with axis deviation (AD) in terms of subsequent pacemaker implantation for high-degree atrioventricular (AV) block or sick sinus syndrome (SSS). Among the 16,170 atomic-bomb survivors in our biennial health examination between July 1967 and December 2010, we detected 520 newly-acquired RBBB subjects with no organic heart disease, and selected 1038 age- (at RBBB diagnosis) and sex-matched subjects without RBBB to serve as comparison subjects. Multivariate Cox regression analysis was used to estimate the hazard ratios (HRs) for the risk of pacemaker implantation due to all causes, AV block or SSS between RBBB and comparison subjects and between RBBB subjects with and without AD. The risk of pacemaker implantation for RBBB was 4.79 (95% confidence interval [CI] 1.89-12.58; P=0.001), 3.77 (95% CI, 1.09-13.07; P=0.036), and 6.28 (95% CI, 1.24-31.73, P=0.026) when implantation was for all causes, AV block and SSS, respectively. RBBB subjects with AD had a higher risk for all-cause pacemaker implantation than subjects without AD (HR, 3.03; 95% CI, 1.00-9.13, P=0.049). RBBB subjects with AD were younger than subjects without AD at the time of RBBB diagnosis (59.4±7.6 vs 74.4±3.1 years old, P=0.019), and their progression from diagnosis to pacemaker implantation took longer (15.1±6.6 vs 6.4±3.0 years, P=0.032). RBBB, especially with AD, progresses to AV block and SSS that requires pacemaker implantation; the mechanisms by which the conduction defect progresses differ among patients with and without AD. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Mefford, Melissa A; Staley, Jonathan P
2009-07-01
During pre-mRNA splicing, the spliceosome must configure the substrate, catalyze 5' splice site cleavage, reposition the substrate, and catalyze exon ligation. The highly conserved U2/U6 helix I, which adjoins sequences that define the reactive sites, has been proposed to configure the substrate for 5' splice site cleavage and promote catalysis. However, a role for this helix at either catalytic step has not been tested rigorously and previous observations question its role at the catalytic steps. Through a comprehensive molecular genetic study of U2/U6 helix I, we found that weakening U2/U6 helix I, but not mutually exclusive structures, compromised splicing of a substrate limited at the catalytic step of 5' splice site cleavage, providing the first compelling evidence that this helix indeed configures the substrate during 5' splice site cleavage. Further, mutations that we proved weaken only U2/U6 helix I suppressed a mutation in PRP16, a DEAH-box ATPase required after 5' splice site cleavage, providing persuasive evidence that helix I is destabilized by Prp16p and suggesting that this structure is unwound between the catalytic steps. Lastly, weakening U2/U6 helix I also compromised splicing of a substrate limited at the catalytic step of exon ligation, providing evidence that U2/U6 helix I reforms and functions during exon ligation. Thus, our data provide evidence for a fundamental and apparently dynamic role for U2/U6 helix I during the catalytic stages of splicing.
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Engbers, Elsemiek M.; Mouden, Mohamed [Isala, Department of Cardiology, Zwolle (Netherlands); Isala, Department of Nuclear Medicine, Zwolle (Netherlands); Timmer, Jorik R.; Ottervanger, Jan Paul [Isala, Department of Cardiology, Zwolle (Netherlands); Knollema, Siert; Jager, Pieter L. [Isala, Department of Nuclear Medicine, Zwolle (Netherlands)
2017-01-15
To investigate the impact of left bundle branch block (LBBB) on sequential single photon emission computed tomography (SPECT)/ CT imaging starting with stress-first SPECT. Consecutive symptomatic low- to intermediate-risk patients without a history of coronary artery disease (CAD) referred for SPECT/CT were included from an observational registry. If stress SPECT was abnormal, additional rest SPECT and, if feasible, coronary CT angiography (CCTA) were acquired. Of the 5,018 patients, 218 (4.3 %) demonstrated LBBB. Patients with LBBB were slightly older than patients without LBBB (65±12 vs. 61±11 years, p<0.001). Stress SPECT was more frequently abnormal in patients with LBBB (82 % vs. 46 %, p<0.001). After reviewing stress and rest images, SPECT was normal in 43 % of the patients with LBBB, compared to 77 % of the patients without LBBB (p<0.001). Sixty-four of the 124 patients with LBBB and abnormal stress-rest SPECT underwent CCTA (52 %), which could exclude obstructive CAD in 46 of the patients (72 %). Sequential SPECT/CT imaging starting with stress SPECT is not the optimal imaging protocol in patients with LBBB, as the majority of these patients have potentially false-positive stress SPECT. First-line testing using CCTA may be more appropriate in low- to intermediate-risk patients with LBBB. (orig.)
Archer, Stephen Lawrence
2008-05-01
A case of left bundle branch block and a dilated, nonhypertrophic cardiomyopathy associated with ingestion of colloidal gold and silver as an 'energy tonic' is described. The cardiac disease was reversed within two months by a course of dimercaprol (Akorn Inc, USA) (British antiLewisite) and vitamin E. This is the first case of gold and silver cardiomyopathy in humans, and highlights the risks of these colloidal metal 'health supplements'.
Maciej Sterliński; Adam Sokal; Radosław Lenarczyk; Frederic Van Heuverswyn; Aldo Rinaldi, C.; Marc Vanderheyden; Vladimir Khalameizer; Darrel Francis; Joeri Heynens; Berthold Stegemann; Richard Cornelussen
2016-01-01
Introduction Recent efforts to increase CRT response by multiSPOT pacing (MSP) from multiple bipols on the same left ventricular lead are still inconclusive. Aim The Left Ventricular (LV) MultiSPOTpacing for CRT (iSPOT) study compared the acute hemodynamic response of MSP pacing by using 3 electrodes on a quadripolar lead compared with conventional biventricular pacing (BiV). Methods Patients with left bundle branch block (LBBB) underwent an acute hemodynamic study to determine the %change in...
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E. N. Pavlyukova
2016-01-01
Full Text Available Influence of left bundle branch block (LBBB on left ventricle (LV diastolic function and mechanisms of LV torsion remains underestimated.Aim. To study the relationship of LV diastolic function and LV torsion in patients with cardiomyopathy and LBBB in comparison with patients with cardiomyopathy and normal intraventricular conduction.Material and methods. Patients with cardiomyopathy (n=74 and LV ejection fraction <40% were included into the study and divided in two groups with narrow QRS complex and LBBB (the mean QRS duration = 153 ms. Echocardiography was performed in all patients with hemodynamic indices detection, and myocardium strain and torsion estimation.Results. The patients with LBBB showed less twisting, than patients without LBBB (3.24±3.35° and 5.87±3.83°, respectively, p=0.013914, but significant diastolic function differences between groups were absent. Despite the lack of difference in heart remodeling indices, subgroup of patients with LV rigid body rotation showed significantly less LV twisting and changes in pulmonary vein flow related to LV high end diastolic pressure. In the rigid body rotation group systolic left atrial filling fraction was 32.3±8.07%, whereas in the group with a physiological counter-rotation - 53.1±10.1% (p=0.000226. Potential reason of these findings was interventricular dyssynchrony. Deviation of time interval to peak myocardial systolic velocity between opposite basal segments in group with LBBB and anomalous LV rotation was more (63.3±35.1 ms than this in group with LBBB and physiological LV rotation (8.0±17.9 mc, p=0.015922. This finding suggests that LV rigid body rotation in patients with LBBB may reflect a more pronounced mechanical dyssynchrony.Conclusion. LBBB has complex negative influence on process of LV electric activation and contraction which results in deterioration of LV twisting, mechanical dyssynchrony and deterioration of diastolic function. In disorders of intraventricular
Institute of Scientific and Technical Information of China (English)
吴梅花
2016-01-01
Objective Discussion of electrocardiographic diagnosis of acute myocardial infarction clinical significance of bundle branch block..Methods From March 2014 to December 2015,72 patients with acute myocardial infarction in patients with bundle branch block as the object of study,after ECG for patients,respectively,traditional programmes and Sgarbossa diagnosis scheme for diagnostic purposes. Observation and comparison of two diagnosis results of the programme.Results The two methods in the negative predictive and diagnostic sensitivity of no significant difference but Sgarbossa positive predictive diagnosis method of rate and specificity than conventional methods.Conclusion Sgarbossa judge diagnosis,can effectively improve the accuracy of electrocardiogram in diagnosis of myocardial infarction.%目的：讨论心电图诊断急性心肌梗死合并束支阻滞的临床意义。方法选取2014年3月至2015年12月，72例患有急性心肌梗死合并束支阻滞的患者为研究对象，对患者进行心电图检查之后，分别以传统诊断方案和Sgarbossa诊断方案进行诊断。观察和比较两中诊断方案的结果。结果两种方法在阴性预测率和诊断敏感性的比较上没有显著差异，但是用Sgarbossa诊断方法的阳性预测率和特异性明显高于传统方法。结论应用Sgarbossa诊断方案进行判断，可以有效的提高心电图诊断心肌梗死的准确率。
Institute of Scientific and Technical Information of China (English)
Zhuo CHEN; Zhang Ju LIU; Yun He SHENG
2014-01-01
In this paper, we construct a category of short exact sequences of vector bundles and prove that it is equivalent to the category of double vector bundles. Moreover, operations on double vector bundles can be transferred to operations on the corresponding short exact sequences. In particular, we study the duality theory of double vector bundles in term of the corresponding short exact sequences. Examples including the jet bundle and the Atiyah algebroid are discussed.
Chen, Zhuo; Liu, Zhangju; Sheng, Yunhe
2011-01-01
In this paper, we construct a category of short exact sequences of vector bundles and prove that it is equivalent to the category of double vector bundles. Moreover, operations on double vector bundles can be transferred to operations on the corresponding short exact sequences. In particular, we study the duality theory of double vector bundles in term of the corresponding short exact sequences. Examples including the jet bundle and the Atiyah algebroid are discussed.
Principal noncommutative torus bundles
DEFF Research Database (Denmark)
Echterhoff, Siegfried; Nest, Ryszard; Oyono-Oyono, Herve
2008-01-01
In this paper we study continuous bundles of C*-algebras which are non-commutative analogues of principal torus bundles. We show that all such bundles, although in general being very far away from being locally trivial bundles, are at least locally trivial with respect to a suitable bundle version...... of bivariant K-theory (denoted RKK-theory) due to Kasparov. Using earlier results of Echterhoff and Williams, we shall give a complete classification of principal non-commutative torus bundles up to equivariant Morita equivalence. We then study these bundles as topological fibrations (forgetting the group...... action) and give necessary and sufficient conditions for any non-commutative principal torus bundle being RKK-equivalent to a commutative one. As an application of our methods we shall also give a K-theoretic characterization of those principal torus-bundles with H-flux, as studied by Mathai...
Presenting Lexical Bundles for Explicit Noticing with Schematic Linguistic Representation
Thomson, Haidee Elizabeth
2016-01-01
Lexical bundles are essential for fluency, but their incompleteness is a stumbling block for learners. In this study, two presentation methods to increase awareness of lexical bundles through explicit noticing are explored and compared with incidental exposure. The three conditions in this study were as follows: noticing with schematic linguistic…
Institute of Scientific and Technical Information of China (English)
王清丽; 金向梅; 张力; 赵激扬
2014-01-01
We have treated 1 case with intermittent left bundle branch block caused by high doses of beta blocker.We briefly reported the treatment experience.%在临床治疗了1例大剂量β受体阻滞剂致间歇性左束支传导阻滞的患者，现将体会简要报告。
Biswas, Indranil
2011-01-01
We construct projectivization of a parabolic vector bundle and a tautological line bundle over it. It is shown that a parabolic vector bundle is ample if and only if the tautological line bundle is ample. This allows us to generalize the notion of a k-ample bundle, introduced by Sommese, to the context of parabolic bundles. A parabolic vector bundle $E_*$ is defined to be k-ample if the tautological line bundle ${\\mathcal O}_{{\\mathbb P}(E_*)}(1)$ is $k$--ample. We establish some properties of parabolic k-ample bundles.
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Cabeda, Estevan Vieira; Rochitte, Carlos Eduardo; Nomura, Cesar Higa; Parga, Jose Rodrigues; Avila, Luiz Francisco Rodrigues; Falcao, Andrea Maria Gomes; Soares Junior, Jose [Instituto do Coracao (InCor), Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil)
2015-12-15
Background: Functional tests have limited accuracy for identifying myocardial ischemia in patients with left bundle branch block (LBBB). Objective: To assess the diagnostic accuracy of dipyridamole-stress myocardial computed tomography perfusion (CTP) by 320-detector CT in patients with LBBB using invasive quantitative coronary angiography (QCA) (stenosis ≥ 70%) as reference; to investigate the advantage of adding CTP to coronary computed tomography angiography (CTA) and compare the results with those of single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy. Methods: Thirty patients with LBBB who had undergone SPECT for the investigation of coronary artery disease were referred for stress tomography. Independent examiners performed per-patient and per-coronary territory assessments. All patients gave written informed consent to participate in the study that was approved by the institution's ethics committee. Results: The patients' mean age was 62 ± 10 years. The mean dose of radiation for the tomography protocol was 9.3 ± 4.6 mSv. With regard to CTP, the per-patient values for sensitivity, specificity, positive and negative predictive values, and accuracy were 86%, 81%, 80%, 87%, and 83%, respectively (p = 0.001). The per-territory values were 63%, 86%, 65%, 84%, and 79%, respectively (p < 0.001). In both analyses, the addition of CTP to CTA achieved higher diagnostic accuracy for detecting myocardial ischemia than SPECT (p < 0.001). Conclusion: The use of the stress tomography protocol is feasible and has good diagnostic accuracy for assessing myocardial ischemia in patients with LBBB. (author)
Lesson Thirteen Trifascicular Block
Institute of Scientific and Technical Information of China (English)
鲁端; 王劲
2005-01-01
@@ A complete trifascicular block would result in complete AV block. The idio ventricular rhythm has a slower rate and a wide QRS complex because the pacemaker is located at the peripheral part of the conduction system distal to the sites of the block1. Such a rhythm may be difficult to differentiate from bifascicular or bundle branch block combined with complete block at a higher level such as the AV node or His bundle2. Besides a slower ventricular rate, a change in the morphology of the QRS complex from a previous known bifascicular pattern would be strongly suggestive of a trifascicular origin of the complete AV block3. A His bundle recording is required for a definitive diagnosis, however.
Lesson Eighteen An Unusual Bundle Branch Block
Institute of Scientific and Technical Information of China (English)
鲁端; 王劲
2006-01-01
@@ The electrocardiographic(Fig. 1) has been recorded from an asymptomatic 52-year-old woman free from organic heart disease,who was admitted to the outpatient department beacause a routine ECG had pointed out some abnormalities1: ①The QRS axis is at +90°, ②The QRS duration is 0.14 seconds, ③ The QRS configuration in the limb leads is suggestive of BBB, but it is hard to define, on the basis of these leads only, which type of BBB (right or left) is involved2.The wide S waves in leads I and aVL suggest at first glance an RBBB, whereas the QRS morphology in the inferior leads (monophasic R wave with secondary ST-T changes) is more consistent with an LBBB with relative right axis deviation, ④The chest leads further complicate the problem because lead V1 suggests an RBBB, whereas leads V5 and V6 are perfectly consistent with an LBBB, showing a monophasic R wave3, in addition, lead V5 shows ST-segment depression and negative T wave, typical of LBBB. It is worth noting that when the tracing was recorded, the correct placement of precordial electrodes was accurately checked, ⑤ Placement of precordial electrodes of leads V4,V5,and V6 2 intercostals spaces above restores4,in these leads, a QRS configuration suggestive of RBBB:small and relatively wide s waves appear and the T waves become positive.
The ABCDEF Implementation Bundle
Directory of Open Access Journals (Sweden)
Annachiara Marra
2016-08-01
Full Text Available Long-term morbidity, long-term cognitive impairment and hospitalization-associated disability are common occurrence in the survivors of critical illness, with significant consequences for patients and for the caregivers. The ABCDEF bundle represents an evidence-based guide for clinicians to approach the organizational changes needed for optimizing ICU patient recovery and outcomes. The ABCDEF bundle includes: Assess, Prevent, and Manage Pain, Both Spontaneous Awakening Trials (SAT and Spontaneous Breathing Trials (SBT, Choice of analgesia and sedation, Delirium: Assess, Prevent, and Manage, Early mobility and Exercise, and Family engagement. The purpose of this review is to describe the core features of the ABCDEF bundle.
Subtleties Concerning Conformal Tractor Bundles
Graham, C Robin
2012-01-01
The realization of tractor bundles as associated bundles in conformal geometry is studied. It is shown that different natural choices of principal bundle with normal Cartan connection corresponding to a given conformal manifold can give rise to topologically distinct associated tractor bundles for the same inducing representation. Consequences for homogeneous models and conformal holonomy are described. A careful presentation is made of background material concerning standard tractor bundles and equivalence between parabolic geometries and underlying structures.
Institute of Scientific and Technical Information of China (English)
单其俊; 邹建刚; 陈椿; 杨兵; 陈明龙; 徐东杰; 侯小峰; 曹克将
2009-01-01
目的 观察左束支阻滞激动模式对心脏功能和结构的影响.方法 3例心功能不良和左心室扩大患者,左心室射血分数(LVEF)0.44 ±0.11,左心室舒张末内径(LVEDD)(56±4)mm,QRS时限增宽(177±15)ms,呈左束支阻滞或左束支阻滞样图形.例1为风湿性心脏病二尖瓣及主动脉瓣置换术后伴左束支阻滞;例2为显性右侧预激综合征;例3 24 h动态心电图示右心室流出道室性早搏(室早)3万次.结果 例1成功行心脏再同步治疗,例2和例3成功行右侧显性旁路和右心室流出道室早消融,QRS时限降至(103±25)ms,随访6～30个月,症状明显改善,心功能恢复正常,左心室明显缩小,LVEF为0.65 ±0.04和LVEDD(48±4)mm.结论 左束支阻滞激动模式是心功能不良重要的可逆性因素.%Objective To investigate the effects of excitation mode of left bundle branch block (LBBB) or LBBB-like on the cardiac function and structure.Methods This study included three patients with depressing cardiac function (LVEF=0.44±0.11 ) and enlarged left ventricle [LVEDD=(56+4)mm).The widen QRS complex (QRS duration=(177±15 )ms] displayed LBBB or LBBB-like was documented in all patients.One patient with serious heart failure had the history of surgical mitral and aortic valves replacement and LBBB.The right ventricular preexcitation and frequent premature ventricular contractions ( more than 30 000 beats per 24 hours) were documented in other 2 patients,respectively.Results The patient with surgical valves replacement and LBBB underwent successful cardiac resynchrunization therapy with biventricular pacing.The para-Hisian accessory pathway and premature ventricular contractions originated from right ventricular outflow tract were ablated successfully in other patients,respectively.After the procedures,the QRS complex became significant narrow [QRS duration=(103±25)ms) in all patients.During the follow-up period of 6 to 30 months,the cardiac function ( LVEF=0.65±0
Directory of Open Access Journals (Sweden)
J. W. Kitchen
1994-01-01
Full Text Available We study bundles of Banach algebras π:A→X, where each fiber Ax=π−1({x} is a Banach algebra and X is a compact Hausdorff space. In the case where all fibers are commutative, we investigate how the Gelfand representation of the section space algebra Γ(π relates to the Gelfand representation of the fibers. In the general case, we investigate how adjoining an identity to the bundle π:A→X relates to the standard adjunction of identities to the fibers.
Principal -bundles on Nodal Curves
Indian Academy of Sciences (India)
Usha N Bhosle
2001-08-01
Let be a connected semisimple affine algebraic group defined over . We study the relation between stable, semistable -bundles on a nodal curve and representations of the fundamental group of . This study is done by extending the notion of (generalized) parabolic vector bundles to principal -bundles on the desingularization of and using the correspondence between them and principal -bundles on . We give an isomorphism of the stack of generalized parabolic bundles on with a quotient stack associated to loop groups. We show that if is simple and simply connected then the Picard group of the stack of principal -bundles on is isomorphic to ⊕ , being the number of components of .
On projective space bundle with nef normalized tautological line bundle
Yasutake, Kazunori
2011-01-01
In this paper, we study the structure of projective space bundles whose relative anti-canonical line bundle is nef. As an application, we get a characterization of abelian varieties up to finite etale covering.
DEFF Research Database (Denmark)
Sommer, Stefan Horst; Lauze, Francois Bernard; Nielsen, Mads
2011-01-01
In the LDDMM framework, optimal warps for image registration are found as end-points of critical paths for an energy functional, and the EPDiff equations describe the evolution along such paths. The Large Deformation Diffeomorphic Kernel Bundle Mapping (LDDKBM) extension of LDDMM allows scale space...
Sepe, D.
2013-01-01
The obstruction to construct a Lagrangian bundle over a fixed integral affine manifold was constructed by Dazord and Delzant (J Differ Geom 26:223–251, 1987) and shown to be given by ‘twisted’ cup products in Sepe (Differ GeomAppl 29(6): 787–800, 2011). This paper uses the topology of universal Lagr
Directory of Open Access Journals (Sweden)
Iosif DUMITRESCU
2015-05-01
Full Text Available In municipal solid waste, aluminum is the main nonferrous metal, approximately 80- 85% of the total nonferrous metals. The income per ton gained from aluminum recuperation is 20 times higher than from glass, steel boxes or paper recuperation. The object of this paper is the design of a 300 kN press for aluminum box bundling.
Deformation quantization of principal bundles
Aschieri, Paolo
2016-01-01
We outline how Drinfeld twist deformation techniques can be applied to the deformation quantization of principal bundles into noncommutative principal bundles, and more in general to the deformation of Hopf-Galois extensions. First we twist deform the structure group in a quantum group, and this leads to a deformation of the fibers of the principal bundle. Next we twist deform a subgroup of the group of authomorphisms of the principal bundle, and this leads to a noncommutative base space. Considering both deformations we obtain noncommutative principal bundles with noncommutative fiber and base space as well.
Rudakov, A N
1990-01-01
This volume is devoted to the use of helices as a method for studying exceptional vector bundles, an important and natural concept in algebraic geometry. The work arises out of a series of seminars organised in Moscow by A. N. Rudakov. The first article sets up the general machinery, and later ones explore its use in various contexts. As to be expected, the approach is concrete; the theory is considered for quadrics, ruled surfaces, K3 surfaces and P3(C).
Bundling harvester; Nippukorjausharvesteri
Energy Technology Data Exchange (ETDEWEB)
Koponen, K. [Eko-Log Oy, Kuopio (Finland)
1996-12-31
The staring point of the project was to design and construct, by taking the silvicultural point of view into account, a harvesting and processing system especially for energy-wood, containing manually driven bundling harvester, automatizing of the harvester, and automatized loading. The equipment forms an ideal method for entrepreneur`s-line harvesting. The target is to apply the system also for owner`s-line harvesting. The profitability of the system promotes the utilization of the system in both cases. The objectives of the project were: to construct a test equipment and prototypes for all the project stages, to carry out terrain and strain tests in order to examine the usability and durability, as well as the capacity of the machine, to test the applicability of the Eko-Log system in simultaneous harvesting of energy and pulp woods, and to start the marketing and manufacturing of the products. The basic problems of the construction of the bundling harvester have been solved using terrain-tests. The prototype machine has been shown to be operable. Loading of the bundles to form sufficiently economically transportable loads has been studied, and simultaneously, the branch-biomass has been tried to be utilized without loosing the profitability of transportation. The results have been promising, and will promote the profitable utilization of wood-energy
Draper, Andrew
2011-04-01
Results of Medicare's ACE demonstration project and Geisinger Health System's ProvenCare initiative provide insight into the challenges hospitals will face as bundled payment proliferates. An early analysis of these results suggests that hospitals would benefit from bringing full automation using clinical IT tools to bear in their efforts to meet these challenges. Other important factors contributing to success include board and physician leadership, organizational structure, pricing methodology for bidding, evidence-based medical practice guidelines, supply cost management, process efficiency management, proactive and aggressive case management, business development and marketing strategy, and the financial management system.
Differential calculi on noncommutative bundles
Pflaum, Markus J.; Schauenburg, Peter
1996-01-01
We introduce a category of noncommutative bundles. To establish geometry in this category we construct suitable noncommutative differential calculi on these bundles and study their basic properties. Furthermore we define the notion of a connection with respect to a differential calculus and consider questions of existence and uniqueness. At the end these constructions are applied to basic examples of noncommutative bundles over a coquasitriangular Hopf algebra.
Institute of Scientific and Technical Information of China (English)
李静超; 楚英杰; 刘晓宇; 杨朝宽
2013-01-01
Objective To evaluate the incidence and clinical impact of right bundle branch block (RBBB) in patients with non-ST elevation myocardial infarction(NSTEMI) and patients with ST elevation myocardial infarction(STEMI).Methods Nine hundred and thirty-one patients with AMI were divided into STEMI team and NSTEMI group,each group was sub divided into right bundle branch block (RBBB) group and none bundle branch block (NBBB) group furtherly according to the ECG appearance.Patients with left bundle branch block were excluded.The difference of baseline clinical characteristics,short-term inhospital treatment,in hospital and one-year mortality between RBBB group and NBBB groups were analyzed.Independent predictors of raised mortality was screened by Logistic regression stepwise method.Results A total of 16 patients(7.14％) with NSTEMI and 47 patients(6.65％) with STEMI presented with RBBB on admission.In general,RBBB patients were older,more often had comorbidities,and less often received short-term inhospital treatment according to guidelines.In STEMI,RBBB patients had higher peak enzyme levels and lower left ventricular ejection fraction (LVEF) than patients without BBB.Right bundle branch block in STEMI was associated with an increased inhospital and long-term mortality.However,peak enzyme levels and LVEF were similar in both groups with and without BBB in NSTEMI.Right bundle branch block in NSTEMI was not independently associated with a worse outcome.Conclusions Unlike RBBB in STEMI,RBBB in NSTEMI is not an independent predictor of inhospital and long-term mortality.%目的 探讨右束支传导阻滞(RBBB)在急性非ST段抬高心肌梗死(NSTEMI)和急性ST段抬高心肌梗死(STEMI)患者中的发生率及其对两组患者临床特征和预后的影响.方法 收集931例急性心肌梗死(AMI)患者的临床资料,将其分为STEMI组和NSTEMI组,且将以上两组分别分为RBBB和无束支传导阻滞(NBBB)4个亚组,追踪随访1年；分析两组中RBBB
Nefness of adjoint bundles for ample vector bundles
Directory of Open Access Journals (Sweden)
Hidetoshi Maeda
1995-11-01
Full Text Available Let E be an ample vector bundle of rank >1 on a smooth complex projective variety X of dimension n. This paper gives a classification of pairs (X,E whose adjoint bundles K_X+det E are not nef in the case when r=n-2.
Bundle Security Protocol for ION
Burleigh, Scott C.; Birrane, Edward J.; Krupiarz, Christopher
2011-01-01
This software implements bundle authentication, conforming to the Delay-Tolerant Networking (DTN) Internet Draft on Bundle Security Protocol (BSP), for the Interplanetary Overlay Network (ION) implementation of DTN. This is the only implementation of BSP that is integrated with ION.
Friedman, R; Witten, Edward
1997-01-01
To understand in detail duality between heterotic string and F theory compactifications, it is important to understand the construction of holomorphic G bundles over elliptic Calabi-Yau manifolds, for various groups G. In this paper, we develop techniques to describe these bundles, and make several detailed comparisons between the heterotic string and F theory.
Friedman, Robert; Morgan, John; Witten, Edward
1997-01-01
To understand in detail duality between heterotic string and F theory compactifications, it is important to understand the construction of holomorphic G bundles over elliptic Calabi-Yau manifolds, for various groups G. In this paper, we develop techniques to describe the bundles, and make several detailed comparisons between the heterotic string and F theory.
Bundle Formation in Biomimetic Hydrogels
Jaspers, Maarten; Pape, A C H; Voets, Ilja K; Rowan, Alan E; Portale, Giuseppe; Kouwer, Paul H J
2016-01-01
Bundling of single polymer chains is a crucial process in the formation of biopolymer network gels that make up the extracellular matrix and the cytoskeleton. This bundled architecture leads to gels with distinctive properties, including a large-pore-size gel formation at very low concentrations and
Fiber bundle phase conjugate mirror
Ward, Benjamin G.
2012-05-01
An improved method and apparatus for passively conjugating the phases of a distorted wavefronts resulting from optical phase mismatch between elements of a fiber laser array are disclosed. A method for passively conjugating a distorted wavefront comprises the steps of: multiplexing a plurality of probe fibers and a bundle pump fiber in a fiber bundle array; passing the multiplexed output from the fiber bundle array through a collimating lens and into one portion of a non-linear medium; passing the output from a pump collection fiber through a focusing lens and into another portion of the non-linear medium so that the output from the pump collection fiber mixes with the multiplexed output from the fiber bundle; adjusting one or more degrees of freedom of one or more of the fiber bundle array, the collimating lens, the focusing lens, the non-linear medium, or the pump collection fiber to produce a standing wave in the non-linear medium.
Directory of Open Access Journals (Sweden)
Alex K Lyashchenko
Full Text Available Hyperpolarization-activated cyclic nucleotide-regulated HCN channels underlie the Na+-K+ permeable IH pacemaker current. As with other voltage-gated members of the 6-transmembrane KV channel superfamily, opening of HCN channels involves dilation of a helical bundle formed by the intracellular ends of S6 albeit this is promoted by inward, not outward, displacement of S4. Direct agonist binding to a ring of cyclic nucleotide-binding sites, one of which lies immediately distal to each S6 helix, imparts cAMP sensitivity to HCN channel opening. At depolarized potentials, HCN channels are further modulated by intracellular Mg2+ which blocks the open channel pore and blunts the inhibitory effect of outward K+ flux. Here, we show that cAMP binding to the gating ring enhances not only channel opening but also the kinetics of Mg2+ block. A combination of experimental and simulation studies demonstrates that agonist acceleration of block is mediated via acceleration of the blocking reaction itself rather than as a secondary consequence of the cAMP enhancement of channel opening. These results suggest that the activation status of the gating ring and the open state of the pore are not coupled in an obligate manner (as required by the often invoked Monod-Wyman-Changeux allosteric model but couple more loosely (as envisioned in a modular model of protein activation. Importantly, the emergence of second messenger sensitivity of open channel rectification suggests that loose coupling may have an unexpected consequence: it may endow these erstwhile "slow" channels with an ability to exert voltage and ligand-modulated control over cellular excitability on the fastest of physiologically relevant time scales.
Twisted Vector Bundles on Pointed Nodal Curves
Indian Academy of Sciences (India)
Ivan Kausz
2005-05-01
Motivated by the quest for a good compactification of the moduli space of -bundles on a nodal curve we establish a striking relationship between Abramovich’s and Vistoli’s twisted bundles and Gieseker vector bundles.
Semiflexible Biopolymers in Bundled Arrangements
Directory of Open Access Journals (Sweden)
Jörg Schnauß
2016-07-01
Full Text Available Bundles and networks of semiflexible biopolymers are key elements in cells, lending them mechanical integrity while also enabling dynamic functions. Networks have been the subject of many studies, revealing a variety of fundamental characteristics often determined via bulk measurements. Although bundles are equally important in biological systems, they have garnered much less scientific attention since they have to be probed on the mesoscopic scale. Here, we review theoretical as well as experimental approaches, which mainly employ the naturally occurring biopolymer actin, to highlight the principles behind these structures on the single bundle level.
Evaluating big deal journal bundles.
Bergstrom, Theodore C; Courant, Paul N; McAfee, R Preston; Williams, Michael A
2014-07-01
Large commercial publishers sell bundled online subscriptions to their entire list of academic journals at prices significantly lower than the sum of their á la carte prices. Bundle prices differ drastically between institutions, but they are not publicly posted. The data that we have collected enable us to compare the bundle prices charged by commercial publishers with those of nonprofit societies and to examine the types of price discrimination practiced by commercial and nonprofit journal publishers. This information is of interest to economists who study monopolist pricing, librarians interested in making efficient use of library budgets, and scholars who are interested in the availability of the work that they publish.
Stable extensions by line bundles
Teixidor-i-Bigas, M
1997-01-01
Let C be an algebraic curve of genus g. Consider extensions E of a vector bundle F'' of rank n'' by a vector bundle F' of rank n'. The following statement was conjectured by Lange: If 0
The Atiyah Bundle and Connections on a Principal Bundle
Indian Academy of Sciences (India)
Indranil Biswas
2010-06-01
Let be a ∞ manifold and a Lie a group. Let $E_G$ be a ∞ principal -bundle over . There is a fiber bundle $\\mathcal{C}(E_G)$ over whose smooth sections correspond to the connections on $E_G$. The pull back of $E_G$ to $\\mathcal{C}(E_G)$ has a tautological connection. We investigate the curvature of this tautological connection.
Bundling ecosystem services in Denmark
DEFF Research Database (Denmark)
Turner, Katrine Grace; Odgaard, Mette Vestergaard; Bøcher, Peder Klith;
2014-01-01
We made a spatial analysis of 11 ecosystem services at a 10 km × 10 km grid scale covering most of Denmark. Our objective was to describe their spatial distribution and interactions and also to analyze whether they formed specific bundle types on a regional scale in the Danish cultural landscape....... We found clustered distribution patterns of ecosystem services across the country. There was a significant tendency for trade-offs between on the one hand cultural and regulating services and on the other provisioning services, and we also found the potential of regulating and cultural services...... to form synergies. We identified six distinct ecosystem service bundle types, indicating multiple interactions at a landscape level. The bundle types showed specialized areas of agricultural production, high provision of cultural services at the coasts, multifunctional mixed-use bundle types around urban...
Vector bundles on toric varieties
Gharib, Saman
2011-01-01
Following Sam Payne's work, we study the existence problem of nontrivial vector bundles on toric varieties. The first result we prove is that every complete fan admits a nontrivial conewise linear multivalued function. Such functions could potentially be the Chern classes of toric vector bundles. Then we use the results of Corti\\~nas, Haesemeyer, Walker and Weibel to show that the (non-equivariant) Grothendieck group of the toric 3-fold studied by Payne is large, so the variety has a nontrivial vector bundle. Using the same computation, we show that every toric 3-fold X either has a nontrivial line bundle, or there is a finite surjective toric morphism from Y to X, such that Y has a large Grothendieck group.
Fabrication of electrospun nanofibers bundles
Ye, Junjun; Sun, Daoheng
2007-12-01
Aligned nanofibers, filament bundle composed of large number of nanofibers have potential applications such as bio-material, composite material etc. A series of electrospinning experiments have been conducted to investigate the electrospinning process,in which some parameters such as polymer solution concentration, bias voltage, distance between spinneret and collector, solution flow rate etc have been setup to do the experiment of nanofibers bundles construction. This work firstly reports electrospun nanofiber bundle through non-uniform electrical field, and nanofibers distributed in different density on electrodes from that between them. Thinner nanofibers bundle with a few numbers of nanofiber is collected for 3 seconds; therefore it's also possible that the addressable single nanofiber could be collected to bridge two electrodes.
Reconnection of superfluid vortex bundles.
Alamri, Sultan Z; Youd, Anthony J; Barenghi, Carlo F
2008-11-21
Using the vortex filament model and the Gross-Pitaevskii nonlinear Schroedinger equation, we show that bundles of quantized vortex lines in He II are structurally robust and can reconnect with each other maintaining their identity. We discuss vortex stretching in superfluid turbulence and show that, during the bundle reconnection process, kelvin waves of large amplitude are generated, in agreement with the finding that helicity is produced by nearly singular vortex interactions in classical Euler flows.
Bundle Formation in Biomimetic Hydrogels.
Jaspers, Maarten; Pape, A C H; Voets, Ilja K; Rowan, Alan E; Portale, Giuseppe; Kouwer, Paul H J
2016-08-08
Bundling of single polymer chains is a crucial process in the formation of biopolymer network gels that make up the extracellular matrix and the cytoskeleton. This bundled architecture leads to gels with distinctive properties, including a large-pore-size gel formation at very low concentrations and mechanical responsiveness through nonlinear mechanics, properties that are rarely observed in synthetic hydrogels. Using small-angle X-ray scattering (SAXS), we study the bundle formation and hydrogelation process of polyisocyanide gels, a synthetic material that uniquely mimics the structure and mechanics of biogels. We show how the structure of the material changes at the (thermally induced) gelation point and how factors such as concentration and polymer length determine the architecture, and with that, the mechanical properties. The correlation of the gel mechanics and the structural parameters obtained from SAXS experiments is essential in the design of future (synthetic) mimics of biopolymer networks.
Principal bundles the classical case
Sontz, Stephen Bruce
2015-01-01
This introductory graduate level text provides a relatively quick path to a special topic in classical differential geometry: principal bundles. While the topic of principal bundles in differential geometry has become classic, even standard, material in the modern graduate mathematics curriculum, the unique approach taken in this text presents the material in a way that is intuitive for both students of mathematics and of physics. The goal of this book is to present important, modern geometric ideas in a form readily accessible to students and researchers in both the physics and mathematics communities, providing each with an understanding and appreciation of the language and ideas of the other.
Creep rupture of fiber bundles
DEFF Research Database (Denmark)
Linga, G.; Ballone, P.; Hansen, Alex
2015-01-01
The creep deformation and eventual breaking of polymeric samples under a constant tensile load F is investigated by molecular dynamics based on a particle representation of the fiber bundle model. The results of the virtual testing of fibrous samples consisting of 40000 particles arranged on Nc=4...
Line bundles and flat connections
Indian Academy of Sciences (India)
INDRANIL BISWAS; GEORG SCHUMACHER
2017-06-01
We prove that there are cocompact lattices $\\Gamma$ in $\\rm SL(2,\\mathbb C)$ with the property that there are holomorphic line bundles $L$ on $\\rm SL(2,\\mathbb C)/ \\Gamma$ with $c_{1}(L) = 0$ such that $L$ does not admit any unitary flat connection.
Vector Bundles over Elliptic Fibrations
Friedman, R; Witten, Edward; Friedman, Robert; Morgan, John W.; Witten, Edward
1997-01-01
This paper gives various methods for constructing vector bundles over elliptic curves and more generally over families of elliptic curves. We construct universal families over generalized elliptic curves via spectral cover methods and also by extensions, and then give a relative version of the construction in families. We give various examples and make Chern class computations.
Quantum principal bundles and corresponding gauge theories
Durdevic, M
1995-01-01
A generalization of classical gauge theory is presented, in the framework of a noncommutative-geometric formalism of quantum principal bundles over smooth manifolds. Quantum counterparts of classical gauge bundles, and classical gauge transformations, are introduced and investigated. A natural differential calculus on quantum gauge bundles is constructed and analyzed. Kinematical and dynamical properties of corresponding gauge theories are discussed.
Strategic and welfare implications of bundling
DEFF Research Database (Denmark)
Martin, Stephen
1999-01-01
A standard oligopoly model of bundling shows that bundling by a firm with a monopoly over one product has a strategic effect because it changes the substitution relationships between the goods among which consumers choose. Bundling in appropriate proportions is privately profitable, reduces rival......' profits and overall welfare, and may drive rivals from the market...
Dendritic bundles, minicolumns, columns, and cortical output units
Directory of Open Access Journals (Sweden)
Giorgio Innocenti
2010-03-01
Full Text Available The search for the fundamental building block of the cerebral cortex has highlighted three structures, perpendicular to the cortical surface: i columns of neurons with radially invariant response properties, e.g., receptive field position, sensory modality, stimulus orientation or direction, frequency tuning etc. ii minicolumns of radially aligned cell bodies and iii bundles, constituted by the apical dendrites of pyramidal neurons with cell bodies in different layers. The latter were described in detail, and sometimes quantitatively, in several species and areas. It was recently suggested that the dendritic bundles consist of apical dendrites belonging to neurons projecting their axons to specific targets. We review the concept above and suggest that another structural and computational unit of cerebral cortex is the cortical output unit (COU, i.e. an assembly of bundles of apical dendrites and their parent cell bodies including each of the outputs to distant cortical or subcortical structures, of a given cortical locus (area or part of an area. This somato-dendritic assembly receives inputs some of which are common to the whole assembly and determine its radially invariant response properties, others are specific to one or more dendritic bundles, and determine the specific response signature of neurons in the different cortical layers and projecting to different targets.
Higher order jet prolongations type gauge natural bundles over vector bundles
Directory of Open Access Journals (Sweden)
Jan Kurek
2004-05-01
Full Text Available Let $rgeq 3$ and $mgeq 2$ be natural numbers and $E$ be a vector bundle with $m$-dimensional basis. We find all gauge natural bundles ``similar" to the $r$-jet prolongation bundle $J^rE$ of $E$. We also find all gauge natural bundles ``similar" to the vector $r$-tangent bundle $(J^r_{fl}(E,R_0^*$ of $E$.
Multipath packet switch using packet bundling
DEFF Research Database (Denmark)
Berger, Michael Stubert
2002-01-01
The basic concept of packet bundling is to group smaller packets into larger packets based on, e.g., quality of service or destination within the packet switch. This paper presents novel applications of bundling in packet switching. The larger packets created by bundling are utilized to extend...... switching capacity by use of parallel switch planes. During the bundling operation, packets will experience a delay that depends on the actual implementation of the bundling and scheduling scheme. Analytical results for delay bounds and buffer size requirements are presented for a specific scheduling...
Dimensional Measurements of Fresh CANDU Fuel Bundle
Energy Technology Data Exchange (ETDEWEB)
Jun, Ji Su; Jo, Chang Keun; Jung, Jong Yeob; Koo, Dae Seo; Cho, Moon Sung [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)
2005-07-01
This paper intends to provide the dimensional measurements of fresh CANDU fuel (37-element) bundle for the estimation of deformation of post-irradiated (PI) bundle. It is expensive and difficult to measure the fretting wear of bearing pad, the element bowing and the waviness of endplate at the two-phase high flow condition (above 24 kg/s) of out-of-reactor test. So, it is recommended to compare the geometry of fresh bundle with that of PI bundle to estimate the integrity of fuel bundle in the CANDU-6 fuel channel with two-phase flow condition. The measurement system has been developed to provide the visual inspection and the dimensional measurements within the accuracy of 10 {mu}m. It is applicable in-air and underwater to the CANDU bundle as well as the CANFLEX bundle. The in-air measurements of the 36 fresh CANDU bundles (S/N: B400892 {approx} B400927) are done by this system from February 2004 to March 2004 in the PHWR fresh fuel storage building of KNFC. These bundles are produced by KNFC manufacturing procedure and are waiting for the delivery to the Wolsong-3 plant, and are planned to load into the proposed test channels. The detail measurements contain the outer rod profile (including the bearing pad), the diameter of bundle, the bowing of bundle, the rod length and the surface profile of end plate (waviness)
Mathematical modelling for nanotube bundle oscillators
Thamwattana, Ngamta; Cox, Barry J.; Hill, James M.
2009-07-01
This paper investigates the mechanics of a gigahertz oscillator comprising a nanotube oscillating within the centre of a uniform concentric ring or bundle of nanotubes. The study is also extended to the oscillation of a fullerene inside a nanotube bundle. In particular, certain fullerene-nanotube bundle oscillators are studied, namely C60-carbon nanotube bundle, C60-boron nitride nanotube bundle, B36N36-carbon nanotube bundle and B36N36-boron nitride nanotube bundle. Using the Lennard-Jones potential and the continuum approach, we obtain a relation between the bundle radius and the radii of the nanotubes forming the bundle, as well as the optimum bundle size which gives rise to the maximum oscillatory frequency for both the fullerene and the nanotube bundle oscillators. While previous studies in this area have been undertaken through molecular dynamics simulations, this paper emphasizes the use of applied mathematical modelling techniques which provides considerable insight into the underlying mechanisms. The paper presents a synopsis of the major results derived in detail by the present authors in [1, 2].
Photonic bandgap fiber bundle spectrometer
Hang, Qu; Syed, Imran; Guo, Ning; Skorobogatiy, Maksim
2010-01-01
We experimentally demonstrate an all-fiber spectrometer consisting of a photonic bandgap fiber bundle and a black and white CCD camera. Photonic crystal fibers used in this work are the large solid core all-plastic Bragg fibers designed for operation in the visible spectral range and featuring bandgaps of 60nm - 180nm-wide. 100 Bragg fibers were chosen to have complimentary and partially overlapping bandgaps covering a 400nm-840nm spectral range. The fiber bundle used in our work is equivalent in its function to a set of 100 optical filters densely packed in the area of ~1cm2. Black and white CCD camera is then used to capture spectrally "binned" image of the incoming light at the output facet of a fiber bundle. To reconstruct the test spectrum from a single CCD image we developed an algorithm based on pseudo-inversion of the spectrometer transmission matrix. We then study resolution limit of this spectroscopic system by testing its performance using spectrally narrow test peaks (FWHM 5nm-25nm) centered at va...
Polarized targeting of L1-CAM regulates axonal and dendritic bundling in vitro.
Barry, Joshua; Gu, Yuanzheng; Gu, Chen
2010-11-01
Proper axonal and dendritic bundling is essential for the establishment of neuronal connections and the synchronization of synaptic inputs, respectively. Cell adhesion molecules of the L1-CAM (L1-cell adhesion molecule) family regulate axon guidance and fasciculation, neuron migration, dendrite morphology, and synaptic plasticity. It remains unclear how these molecules play so many different roles. Here we show that polarized axon-dendrite targeting of an avian L1-CAM protein, NgCAM (neuron-glia cell adhesion molecule), can regulate the switch of bundling of the two major compartments of rat hippocampal neurons. Using a new in-vitro model for studying neurite-neurite interactions, we found that expressed axonal NgCAM induced robust axonal bundling via the trans-homophilic interaction of immunoglobulin domains. Interestingly, dendritic bundling was induced by the dendritic targeting of NgCAM, caused by either deleting its fibronectin repeats or blocking activities of protein kinases. Consistent with the NgCAM results, expression of mouse L1-CAM also induced axonal bundling and blocking kinase activities disrupted its axonal targeting. Furthermore, the trans-homophilic interaction stabilized the bundle formation, probably through recruiting NgCAM proteins to contact sites and promoting guided axon outgrowth. Taken together, our results suggest that precise localization of L1-CAM is important for establishing proper cell-cell contacts in neural circuits.
Conformal Nets II: Conformal Blocks
Bartels, Arthur; Douglas, Christopher L.; Henriques, André
2017-03-01
Conformal nets provide a mathematical formalism for conformal field theory. Associated to a conformal net with finite index, we give a construction of the `bundle of conformal blocks', a representation of the mapping class groupoid of closed topological surfaces into the category of finite-dimensional projective Hilbert spaces. We also construct infinite-dimensional spaces of conformal blocks for topological surfaces with smooth boundary. We prove that the conformal blocks satisfy a factorization formula for gluing surfaces along circles, and an analogous formula for gluing surfaces along intervals. We use this interval factorization property to give a new proof of the modularity of the category of representations of a conformal net.
Conformal Nets II: Conformal Blocks
Bartels, Arthur; Douglas, Christopher L.; Henriques, André
2017-08-01
Conformal nets provide a mathematical formalism for conformal field theory. Associated to a conformal net with finite index, we give a construction of the `bundle of conformal blocks', a representation of the mapping class groupoid of closed topological surfaces into the category of finite-dimensional projective Hilbert spaces. We also construct infinite-dimensional spaces of conformal blocks for topological surfaces with smooth boundary. We prove that the conformal blocks satisfy a factorization formula for gluing surfaces along circles, and an analogous formula for gluing surfaces along intervals. We use this interval factorization property to give a new proof of the modularity of the category of representations of a conformal net.
General frame structures on quantum principal bundles
Durdevic, M
1996-01-01
A noncommutative-geometric generalization of the classical formalism of frame bundles is developed, incorporating into the theory of quantum principal bundles the concept of the Levi-Civita connection. The construction of a natural differential calculus on quantum principal frame bundles is presented, including the construction of the associated differential calculus on the structure group. General torsion operators are defined and analyzed. Illustrative examples are presented.
ACM Bundles on Del Pezzo surfaces
Directory of Open Access Journals (Sweden)
Joan Pons-Llopis
2009-11-01
Full Text Available ACM rank 1 bundles on del Pezzo surfaces are classified in terms of the rational normal curves that they contain. A complete list of ACM line bundles is provided. Moreover, for any del Pezzo surface X of degree less or equal than six and for any n ≥ 2 we construct a family of dimension ≥ n − 1 of non-isomorphic simple ACM bundles of rank n on X.
Entropy for frame bundle systems and Grassmann bundle systems induced by a diffeomorphism
Institute of Scientific and Technical Information of China (English)
SUN; Weniang(孙文祥)
2002-01-01
ALiao hyperbolic diffeomorphism has equal measure entropy and topological entropy to that ofits induced systems on frame bundles and Grassmann bundles. This solves a problem Liao posed in 1996 forLiao hyperbolic diffeomorphisms.
Hydraulic characteristics of HANARO fuel bundles
Energy Technology Data Exchange (ETDEWEB)
Cho, S.; Chung, H. J.; Chun, S. Y.; Yang, S. K.; Chung, M. K. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)
1997-12-31
This paper presents the hydraulic characteristics measured by using LDV (Laser Doppler Velocimetry) in subchannels of HANARO, KAERI research reactor, fuel bundle. The fuel bundle consists of 18 axially finned rods with 3 spacer grids, which are arranged in cylindrical configuration. The effects of the spacer grids on the turbulent flow were investigated by the experimental results. Pressure drops for each component of the fuel bundle were measured, and the friction factors of fuel bundle and loss coefficients for the spacer grids were estimated from the measured pressure drops. Implications regarding the turbulent thermal mixing were discussed. Vibration test results measured by using laser vibrometer were presented. 9 refs., 12 figs. (Author)
Thermal Hydraulic Performance of Tight Lattice Bundle
Yamamoto, Yasushi; Akiba, Miyuki; Morooka, Shinichi; Shirakawa, Kenetsu; Abe, Nobuaki
Recently, the reduced moderation spectrum BWR has been studied. The fast neutron spectrum is obtained through triangular tight lattice fuel. However, there are few thermal hydraulic test data and thermal hydraulic correlation applicable to critical power prediction in such a tight lattice bundle. This study aims to enhance the database of the thermal hydraulic performance of the tight lattice bundle whose rod gap is about 1mm. Therefore, thermal hydraulic performance measurement tests of tight lattice bundles for the critical power, the pressure drop and the counter current flow limiting were performed. Moreover, the correlations to evaluate the thermal-hydraulic performance of the tight lattice bundle were developed.
Principal $G$-bundles over elliptic curves
Friedman, R; Witten, Edward; Friedman, Robert; Morgan, John W.; Witten, Edward
1997-01-01
Let $G$ be a simple and simply connected complex Lie group. We discuss the moduli space of holomorphic semistable principal $G$-bundles over an elliptic curve $E$. In particular, we give a new proof of a theorem of Looijenga and Bernshtein-Shvartsman, that the moduli space is a weighted projective space. The method of proof is to study the deformations of certain unstable bundles coming from special maximal parabolic subgroups of $G$. We also discuss the associated automorphism sheaves and universal bundles, as well as the relation between various universal bundles and spectral covers.
Statistical Constitutive Equation of Aramid Fiber Bundles
Institute of Scientific and Technical Information of China (English)
熊杰; 顾伯洪; 王善元
2003-01-01
Tensile impact tests of aramid (Twaron) fiber bundles were carried om under high strain rates with a wide range of 0. 01/s～1000/s by using MTS and bar-bar tensile impact apparatus. Based on the statistical constitutive model of fiber bundles, statistical constitutive equations of aramid fiber bundles are derived from statistical analysis of test data at different strain rates. Comparison between the theoretical predictions and experimental data indicates statistical constitutive equations fit well with the experimental data, and statistical constitutive equations of fiber bundles at different strain rates are valid.
Jacobi Structures on Affine Bundles
Institute of Scientific and Technical Information of China (English)
J. GRABOWSKI; D. IGLESIAS; J. C. MARRERO; E. PADR(O)N; P. URBA(N)SKI
2007-01-01
We study affine Jacobi structures (brackets) on an affine bundle π: A→M, i.e. Jacobi brackets that close on affine functions. We prove that if the rank of A is non-zero, there is a one-to- one correspondence between affine Jacobi structures on A and Lie algebroid structures on the vector bundle A+=∪p∈M Aff(Ap, R) of affine functionals. In the case rank A = 0, it is shown that there is a one-to-one correspondence between affins Jacobi structures on A and local Lie algebras on A+. Some examples and applications, also for the linear case, are discussed. For a special type of affine Jacobi structures which are canonically exhibited (strongly-affine or affine-homogeneous Jacobi structures) over a real vector space of finite dimension, we describe the leaves of its characteristic foliation as the orbits of an affine representation. These afline Jacobi structures can be viewed as an analog of the Kostant-Arnold-LiouviUe linear Poisson structure on the dual space of a real finite-dimensional Lie algebra.
Institute of Scientific and Technical Information of China (English)
邱春光; 王徐乐; 韩战营; 卢文杰; 陈晓杰
2012-01-01
目的:观察右心房、左心室起搏治疗慢性心力衰竭(心衰)伴左束支传导阻滞患者的短期疗效.方法:选择纽约心功能分级(NYHA)Ⅲ级～Ⅳ级、左心室射血分数≤0.35、体表心电图QRS时限≥120 ms、窦性心律的心衰患者26例,成功植入三腔起搏器后,以右心房、左心室起搏模式治疗7天,以起搏器植入术前及术后第7天的6分钟步行距离、明尼苏达生活质量评分、QRS波时限、左心室舒张末期内径、左心室射血分数、左心室室间隔部与侧壁基底段收缩期达峰时间差值、N末端脑钠肽为疗效评价指标,观察右心房、左心室起搏治疗慢性心衰的短期疗效.结果:右心房、左心室起搏治疗术后第7天较术前比较,6分钟步行距离由术前的( 279±46)m提高至(312±37)m；明尼苏达生活质量评分由术前的(28±7)下降至(22±5)；体表心电图QRS波时限由术前的(167±22)ms缩短至(132±8)ms;左心室射血分数由术前的(0.29±0.07)提高至(0.33±0.05)；左心室舒张末期内径由术前的(75±8)mm减小至(69±7)mm；左心室室间隔部与侧壁基底段收缩期达峰时间差值由术前的(105±29)ms下降至(62±8)ms；N末端脑钠肽由术前的(3 086±1 265)pg/ml下降至(1 976±760)pg/ml；患者的各疗效评价指标均得到明显改善,差异均有统计学意义(P＜0.05).结论:对窦性心律、完全性左束支传导阻滞的慢性心衰患者右心房、左心室起搏的短期疗效确切.%Objective:To observe the short-term effect of right atrial and left uni-ventricular pacing in patients of chronic heart failure with left bundle-branch block.Methods; A total of 26 heart failure patients who had NYHA class III to IV .with sinus rhythm,left ventricular ejection fraction (LVEF) ≤ 0. 35, QRS duration ≥s 0. 12 ms were studied after successful implantation of CRT/CRTD. All patients received right atrial and left uni-ventricular pacing for 7 days. The therapeutic effects
Principal Bundles on the Projective Line
Indian Academy of Sciences (India)
V B Mehta; S Subramanian
2002-08-01
We classify principal -bundles on the projective line over an arbitrary field of characteristic ≠ 2 or 3, where is a reductive group. If such a bundle is trivial at a -rational point, then the structure group can be reduced to a maximal torus.
Anatomic Double-bundle ACL Reconstruction
V.M. Schreiber; C.F. van Eck; F.H. Fu
2010-01-01
Rupture of the anterior cruciate ligament (ACL) is one of the most frequent forms of knee trauma. The traditional surgical treatment for ACL rupture is single-bundle reconstruction. However, during the past few years there has been a shift in interest toward double-bundle reconstruction to closely r
The Verlinde formula for Higgs bundles
Andersen, Jørgen Ellegaard; Pei, Du
2016-01-01
We propose and prove the Verlinde formula for the quantization of the Higgs bundle moduli spaces and stacks for any simple and simply-connected group. This generalizes the equivariant Verlinde formula for the case of $SU(n)$ proposed previously by the second and third author. We further establish a Verlinde formula for the quantization of parabolic Higgs bundle moduli spaces and stacks.
Volkov, Alexey N.; Salaway, Richard N.; Zhigilei, Leonid V.
2013-09-01
The propensity of carbon nanotubes (CNTs) to self-organize into continuous networks of bundles has direct implications for thermal transport properties of CNT network materials and defines the importance of clear understanding of the mechanisms and scaling laws governing the heat transfer within the primary building blocks of the network structures—close-packed bundles of CNTs. A comprehensive study of the thermal conductivity of CNT bundles is performed with a combination of non-equilibrium molecular dynamics (MD) simulations of heat transfer between adjacent CNTs and the intrinsic conductivity of CNTs in a bundle with a theoretical analysis that reveals the connections between the structure and thermal transport properties of CNT bundles. The results of MD simulations of heat transfer in CNT bundles consisting of up to 7 CNTs suggest that, contrary to the widespread notion of strongly reduced conductivity of CNTs in bundles, van der Waals interactions between defect-free well-aligned CNTs in a bundle have negligible effect on the intrinsic conductivity of the CNTs. The simulations of inter-tube heat conduction performed for partially overlapping parallel CNTs indicate that the conductance through the overlap region is proportional to the length of the overlap for CNTs and CNT-CNT overlaps longer than several tens of nm. Based on the predictions of the MD simulations, a mesoscopic-level model is developed and applied for theoretical analysis and numerical modeling of heat transfer in bundles consisting of CNTs with infinitely large and finite intrinsic thermal conductivities. The general scaling laws predicting the quadratic dependence of the bundle conductivity on the length of individual CNTs in the case when the thermal transport is controlled by the inter-tube conductance and the independence of the CNT length in another limiting case when the intrinsic conductivity of CNTs plays the dominant role are derived. An application of the scaling laws to bundles of
Line bundle embeddings for heterotic theories
Energy Technology Data Exchange (ETDEWEB)
Groot Nibbelink, Stefan [Muenchen Univ. (Germany). Arnold Sommerfeld Center for Theoretical Physics; Ruehle, Fabian [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2016-03-15
In heterotic string theories consistency requires the introduction of a non-trivial vector bundle. This bundle breaks the original ten-dimensional gauge groups E{sub 8} x E{sub 8} or SO(32) for the supersymmetric heterotic string theories and SO(16) x SO(16) for the non-supersymmetric tachyon-free theory to smaller subgroups. A vast number of MSSM-like models have been constructed up to now, most of which describe the vector bundle as a sum of line bundles. However, there are several different ways of describing these line bundles and their embedding in the ten-dimensional gauge group. We recall and extend these different descriptions and explain how they can be translated into each other.
Requirements for disordered actomyosin bundle contractility
Lenz, Martin
2011-01-01
Actomyosin contractility is essential for biological force generation, and is well understood in highly ordered structures such as striated muscle. In vitro experiments have shown that non-sarcomeric bundles comprised only of F-actin and myosin thick filaments can also display contractile behavior, which cannot be described by standard muscle models. Here we investigate the microscopic symmetries underlying this process in large non-sarcomeric bundles with long actin filaments. We prove that contractile behavior requires non-identical motors that generate large enough forces to probe the nonlinear elastic behavior of F-actin. A simple disordered bundle model demonstrates a contraction mechanism based on these assumptions and predicts realistic bundle deformations. Recent experimental observations of F-actin buckling in in vitro contractile bundles support our model.
Line bundle embeddings for heterotic theories
Nibbelink, Stefan Groot
2016-01-01
In heterotic theories consistency requires the introduction of a non-trivial vector bundle. This bundle breaks the original ten-dimensional gauge groups E_8 x E_8 or SO(32) for the supersymmetric heterotic theories and SO(16) x SO(16) for the non-supersymmetric tachyon-free theory to smaller subgroups. A vast number of MSSM-like models have been constructed up to now, most of which describe the vector bundle as a sum of line bundles. However, there are several different ways of describing these line bundles and their embedding in the ten-dimensional gauge group. We recall and extend these different descriptions and explain how they can be translated into each other.
Line bundle embeddings for heterotic theories
Nibbelin, Stefan Groot; Ruehle, Fabian
2016-04-01
In heterotic string theories consistency requires the introduction of a non-trivial vector bundle. This bundle breaks the original ten-dimensional gauge groups E8 × E8 or SO(32) for the supersymmetric heterotic string theories and SO(16) × SO(16) for the non-supersymmetric tachyon-free theory to smaller subgroups. A vast number of MSSM-like models have been constructed up to now, most of which describe the vector bundle as a sum of line bundles. However, there are several different ways of describing these line bundles and their embedding in the ten-dimensional gauge group. We recall and extend these different descriptions and explain how they can be translated into each other.
Composite spinor bundles in gravitation theory
Sardanashvily, G
1995-01-01
In gravitation theory, the realistic fermion matter is described by spinor bundles associated with the cotangent bundle of a world manifold X. In this case, the Dirac operator can be introduced. There is the 1:1 correspondence between these spinor bundles and the tetrad gravitational fields represented by sections of the quotient \\Si of the linear frame bundle over X by the Lorentz group. The key point lies in the fact that different tetrad fields imply nonequivalent representations of cotangent vectors to X by the Dirac's matrices. It follows that a fermion field must be regarded only in a pair with a certain tetrad field. These pairs can be represented by sections of the composite spinor bundle S\\to\\Si\\to X where values of tetrad fields play the role of parameter coordinates, besides the familiar world coordinates.
Double Fell bundles and Spectral triples
Martins, Rachel A D
2007-01-01
As a natural and canonical extension of Kumjian's Fell bundles over groupoids \\cite{fbg}, we give a definition for a double Fell bundle (a double category) over a double groupoid. We show that finite dimensional double category Fell line bundles tensored with their dual with $S^o$-reality satisfy the finite real spectral triples axioms but not necessarily orientability. This means that these product bundles with noncommutative algebras can be regarded as noncommutative compact manifolds more general than real spectral triples as they are not necessarily orientable. By construction, they unify the noncommutative geometry axioms and hence provide an algebraic enveloping structure for finite spectral triples to give the Dirac operator $D$ new algebraic and geometric structures that are otherwise missing in the transition from Fredholm operator to Dirac operator. The Dirac operator in physical applications as a result becomes less ad hoc. The new noncommutative space we present is a complex line bundle over a dou...
On Harder–Narasimhan Reductions for Higgs Principal Bundles
Indian Academy of Sciences (India)
Arijit Dey; R Parthasarathi
2005-05-01
The existence and uniqueness of – reduction for the Higgs principal bundles over nonsingular projective variety is shown. We also extend the notion of – reduction for (, )-bundles and ramified -bundles over a smooth curve.
Functional bundles of the medial patellofemoral ligament.
Kang, Hui Jun; Wang, Fei; Chen, Bai Cheng; Su, Yan Ling; Zhang, Zhan Chi; Yan, Chang Bao
2010-11-01
The purpose of this study was to explore the anatomy and evaluate the function of the medial patellofemoral ligament (MPFL). Anatomical dissection was performed on 12 fresh-frozen knee specimens. The MPFL is a condensation of capsular fibers, which originates at the medial femoral condyle. It runs transversely and inserts to the medial edge of the patella. With the landmark of the medial femur epicondyle (MFE), the femoral origination was located: just 8.90 ± 3.27 mm proximally and 13.47 ± 3.68 mm posteriorly to the MFE. The most interesting finding in present study was functional bundles of its patellar insertion. Approximately from the femoral origination point, fibers of the MPFL form two relatively concentrated fiber bundles: the inferior-straight bundle and the superior-oblique bundle. The whole length of each was 71.78 ± 5.51 and 73.67 ± 5.40 mm, respectively. The included angle between bundles was 15.1° ± 2.1°. Although the superior-oblique bundle and the inferior-straight bundle run on the patellar MPFL inferiorly and superiorly, respectively, as their name indicates, the two bundles are not entirely separated, which make MPFL one intact structure. The inferior-straight bundle is the main static soft tissue restraints where the superior-oblique bundle associated with vastus medialis obliquus (VMO) is to serve as the main dynamic soft tissue restraints. So this finding may provide the theoretical foundation for the anatomical reconstruction of the MPFL and shed lights on the future researchers.
Institute of Scientific and Technical Information of China (English)
戴伟川; 冉启川
2013-01-01
Objective To study the value of scoring method used in distinguishing the nature of complete right bundle branch block (CRBBB).Methods The CRBBB relevant parameters of 128 cases organic heart disease patients and those of 144 cases of healthy people were compared.Results The compositions of scoring method are:CRBBB with primary ST-T change、Cardiac electric axis left deviation＜-30°or right deviation＞+110°、J-Tc interval＞0.32s (five points for each),QRS wave time ≥0.16s (four points)、QRS wave time＞0.14s、V1 lead R peak time≥0.10s (three points),V5 lead S wave duration＞0.08s、age≥60 year (two points for each),total score ≥5 points,it will be judged as pathological CRBBB,if it is ＜5,it will be judged as functional CRBBB.Using the single index to distinguish CRBBB led to low sensitiveness(2.34％～83.59％) and specificity (22.22％～100.00％),while using the scoring method generated high sensitiveness (85.16％) and specificity(91.67％),as well as higher accuracy(88.60％).Conclusions The scoring method is a good way of distinguishing the nature of CRBBB in clinical application.%目的 探讨记分法判别完全性右束支传导阻滞(CRBBB)性质的价值.方法 比较128例器质性心脏病患者和144例健康人CRBBB相关参数,并按阳性预测值高低赋予不同分值,构成记分法标准.结果 记分法构成,CRBBB伴原发性ST-T改变、心电轴左偏＜-30°或右偏＞+110°、J-Tc间期＞0.32s各记5分,QRS波时限≥0.16s记4分,V1导联R峰时间≥0.10s记3分,QRS波时限＞0.14s、v5导联S波时限＞0.08s、年龄≥60岁各记2分,总积分≥5分者判为病理性CRBBB,＜5分者判为功能性CRBBB.单项指标判别CRBBB性质敏感度低(2.34％～83.59％)或特异度不高(22.22％～1 00.00％),记分法判别CRBBB性质则有较高敏感度(85.16％)、特异度(91.67％)和预测准确性(88.60％).结论 记分法对判别CRBBB性质有较好的临床应用价值.
Turner, W.
2007-01-01
Consider representation theory associated to symmetric groups, or to Hecke algebras in type A, or to q-Schur algebras, or to finite general linear groups in non-describing characteristic. Rock blocks are certain combinatorially defined blocks appearing in such a representation theory, first observed by R. Rouquier. Rock blocks are much more symmetric than general blocks, and every block is derived equivalent to a Rock block. Motivated by a theorem of J. Chuang and R. Kessar in the case of sym...
Higgs bundles and the real symplectic group
Gothen, Peter B
2011-01-01
We give an overview of the work of Corlette, Donaldson, Hitchin and Simpson leading to the non-abelian Hodge theory correspondence between representations of the fundamental group of a surface and the moduli space of Higgs bundles. We then explain how this can be generalized to a correspondence between character varieties for representations of surface groups in real Lie groups G and the moduli space of G-Higgs bundles. Finally we survey recent joint work with Bradlow, Garc\\'ia-Prada and Mundet i Riera on the moduli space of maximal Sp(2n,R)-Higgs bundles.
Mobility of Taxol in Microtubule Bundles
Ross, J.
2003-06-01
Mobility of taxol inside microtubules was investigated using fluorescence recovery after photobleaching (FRAP) on flow-aligned bundles. Bundles were made of microtubules with either GMPCPP or GTP at the exchangeable site on the tubulin dimer. Recovery times were sensitive to bundle thickness and packing, indicating that taxol molecules are able to move laterally through the bundle. The density of open binding sites along a microtubule was varied by controlling the concentration of taxol in solution for GMPCPP samples. With > 63% sites occupied, recovery times were independent of taxol concentration and, therefore, inversely proportional to the microscopic dissociation rate, k_{off}. It was found that 10*k_{off} (GMPCPP) ~ k_{off} (GTP), consistent with, but not fully accounting for, the difference in equilibrium constants for taxol on GMPCPP and GTP microtubules. With taxol along the microtubule interior is hindered by rebinding events when open sites are within ~7 nm of each other.
Noncommutative principal bundles through twist deformation
Aschieri, Paolo; Pagani, Chiara; Schenkel, Alexander
2016-01-01
We construct noncommutative principal bundles deforming principal bundles with a Drinfeld twist (2-cocycle). If the twist is associated with the structure group then we have a deformation of the fibers. If the twist is associated with the automorphism group of the principal bundle, then we obtain noncommutative deformations of the base space as well. Combining the two twist deformations we obtain noncommutative principal bundles with both noncommutative fibers and base space. More in general, the natural isomorphisms proving the equivalence of a closed monoidal category of modules and its twist related one are used to obtain new Hopf-Galois extensions as twists of Hopf-Galois extensions. A sheaf approach is also considered, and examples presented.
Design requirements of ACR-1000 fuel bundle
Energy Technology Data Exchange (ETDEWEB)
Gossain, D.; Reid, P. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada)
2008-07-01
The design process for ACR-1000 fuel bundle is being undertaken in accordance with the CSA standard N286.2. As an element of the process, the design requirements were established early in the design phase and compiled in the ACR-1000 Fuel Design Requirements (DR) document. The ACR-1000 fuel bundle design is being developed to meet these requirements. This paper discusses the sources for the requirements such as the ACR project requirements, the plant specifications and regulatory requirements. It also discusses considerations of reactor design decisions and operational decisions in establishing functional, performance, safety and other design requirements for the fuel bundle. The design requirements for the ACR-1000 fuel bundle are summarized and the relationship of the requirements to the plant states of Normal Operation, Anticipated Operational Occurrences (AOOs) and Design Basis Accidents (DBAs) are discussed. Structure of the document to capture all the requirements in addition to functional, performance and safety requirements is presented. (author)
Bundled Hybrid Offset Riser Global Strength Analysis
Institute of Scientific and Technical Information of China (English)
William C.Webster; Zhuang Kang; Wenzhou Liang; Youwei Kang; Liping Sun
2011-01-01
Bundled hybrid offset riser(BHOR)global strength analysis,which is more complex than single line offset riser global strength analysis,was carried out in this paper.At first,the equivalent theory is used to deal with BHOR,and then its global strength in manifold cases was analyzed,along with the use of a three-dimensional nonlinear time domain finite element program.So the max bending stress,max circumferential stress,and max axial stress in the BHOR bundle main section(BMS)were obtained,and the values of these three stresses in each riser were obtained through the "stress distribution method".Finally,the Max Von Mises stress in each riser was given and a check was made whether or not they met the demand.This paper provides a reference for strength analysis of the bundled hybrid offset riser and some other bundled pipelines.
Liquid Flow in Shaped Fiber Bundle
Institute of Scientific and Technical Information of China (English)
ZHANG Yan; WANG Hua-ping; CHEN Yue-hua
2006-01-01
By computation and comparison of the critical spreading coefficient parameter, it was found that shaped fiber bundle is better for wetting. Liquid-air interface tension of liquid arising the shaped fiber bundle body is considered as one critical factor besides liquid viscosity, inertia force and liquid-fiber interface tension. Experimental result simulation demonstrated that the liquid-air interface tension is correlated with the geometric size of the liquid arising in body, φ0 (x) and which is affected by the cross sectional shape of fiber and the radius of single fiber. The shaped fiber bundle model is introduced to investigate liquid flow in fiber assembly. The model is generated based on a random function for stochastic forming of fibers in bundle and it is necessary to combine this fundamental model with physical explanation for investigation of liquid flow in fiber assembly.
Dynamic bi-product bundle pricing problem
Directory of Open Access Journals (Sweden)
Rafiei Hamed
2014-01-01
Full Text Available This paper addresses bundle pricing problem of two products in a stochastic environment so as to maximize net profit of a retailer. In the considered problem, it is assumed that customers are received upon a Poisson distribution and their demands follow a bi-variant distribution function. Also, it is assumed that products are sold individually or in the form of a bundle, which are offered from an initial stock of the products. To tackle the problem, a stochastic dynamic program is developed in which optimum values of the initial stock and order quantities of every planning period are determined. Moreover, prices of the individual products and their bundle are optimized. Also, the proposed dynamic program tackles bundling/ unbundling decisions taken in every planning period. A numerical example of a two planning period horizon is considered to validate the proposed model.
Institute of Scientific and Technical Information of China (English)
YU Wei-dong; YAN Hao-jing; Ron Postle; Yang Shouren
2002-01-01
Due to the effects of samples and testing conditions on fibre-bundle tensile behaviour, it is necessary to investigate the relationships between experimental factors and tensile properties for the fibre-bumdle tensile tester (TENSOR). The effects of bundle sample preparation, fibre bundle mass and fibre alignment have been tested. The experimental results indicated that (1) the low damage in combing and no free-end fibres in the cut bundle are most important for the sample preparation; (2) the reasonable bundle mass is 400- 700tex, but the tensile properties measured should bemodified with the bundle mass because a small amount of bundle mass causes the scatter results, while the larger is the bundle mass, the more difficult to comb fibres parallel and to clamp fibre evenly; and (3) the fibre irregular arrangement forms a slack bundle resulting in interaction between fibres, which will affect the reproducibility and accuracy of the tensile testing.
A Geometric Approach to Noncommutative Principal Bundles
Wagner, Stefan
2011-01-01
From a geometrical point of view it is, so far, not sufficiently well understood what should be a "noncommutative principal bundle". Still, there is a well-developed abstract algebraic approach using the theory of Hopf algebras. An important handicap of this approach is the ignorance of topological and geometrical aspects. The aim of this thesis is to develop a geometrically oriented approach to the noncommutative geometry of principal bundles based on dynamical systems and the representation theory of the corresponding transformation group.
Supporting the Secure Deployment of OSGi Bundles
Parrend, Pierre; Frénot, Stéphane
2007-01-01
International audience; The OSGi platform is a lightweight management layer over a Java virtual machine that makes runtime extensi- bility and multi-application support possible in mobile and constraint environments. This powerfull capability opens a particular attack vector against mobile platforms: the in- stallation of malicious OSGi bundles. The first countermea- sure is the digital signature of the bundles. We developed a tool suite that supports the signature, the publication and the va...
Second-Degree Interatrial Block in Hemodialysis Patients
Directory of Open Access Journals (Sweden)
Andres Enriquez
2015-01-01
Full Text Available Interatrial conduction delays manifest as a prolonged P-wave duration on surface ECG and the term interatrial block (IAB has been coined. They are usually fixed, but cases of intermittent IAB have been described, suggesting functional conduction block at the Bachmann bundle region. We report 2 cases of patients on chronic hemodialysis therapy presenting with intermittent IAB.
Second-Degree Interatrial Block in Hemodialysis Patients
Enriquez, Andres; D'Amato, Anna; de Luna, Antoni Bayes; Baranchuk, Adrian
2015-01-01
Interatrial conduction delays manifest as a prolonged P-wave duration on surface ECG and the term interatrial block (IAB) has been coined. They are usually fixed, but cases of intermittent IAB have been described, suggesting functional conduction block at the Bachmann bundle region. We report 2 cases of patients on chronic hemodialysis therapy presenting with intermittent IAB. PMID:25755895
Twisted Bundle on Noncommutative Space and U(1) Instanton
Ho, P M
2000-01-01
We study the notion of twisted bundles on noncommutative space. Due to theexistence of projective operators in the algebra of functions on thenoncommutative space, there are twisted bundles with non-constant dimension.The U(1) instanton solution of Nekrasov and Schwarz is such an example. As amathematical motivation for not excluding such bundles, we find gaugetransformations by which a bundle with constant dimension can be equivalent toa bundle with non-constant dimension.
LWR nuclear fuel bundle data for use in fuel bundle handling
Energy Technology Data Exchange (ETDEWEB)
Weihermiller, W.B.; Allison, G.S.
1979-09-01
Although increasing numbers of spent light water reactor (LWR) fuel bundles are moved into storage, no handling equipment is set up to manipulate all of the various types of fuel bundles. This report summarizes fuel bundle information of interest to the designer of such handling equipment. Dimensional descriptions are included with discussions of assembly procedure and manufacturer provisions for handling equipment. No attempt is made to make a complete compilation of dimensional information; the number of fuel bundle designs and design revisions makes it impractical. Because the fuel bundle designs are so varied, any equipment intended for handling all types of bundles will have to be designed with flexibility in mind. Besides the ability to manipulate fuel bundles in space, handling equipment may be required to locate an external surface or to position a cutting operation to avoid breaking a fuel rod pressure boundary. Even with the most sophisticated and flexible handling equipment, some situations will require use of the manufacturers' as-built descriptions of individual fuel bundles.
Smith, Martin H.
1992-01-01
Describes an educational game called "Population Blocks" that is designed to illustrate the concept of exponential growth of the human population and some potential effects of overpopulation. The game material consists of wooden blocks; 18 blocks are painted green (representing land), 7 are painted blue (representing water); and the remaining…
Smith, Martin H.
1992-01-01
Describes an educational game called "Population Blocks" that is designed to illustrate the concept of exponential growth of the human population and some potential effects of overpopulation. The game material consists of wooden blocks; 18 blocks are painted green (representing land), 7 are painted blue (representing water); and the remaining…
The histology of retinal nerve fiber layer bundles and bundle defects.
Radius, R L; Anderson, D R
1979-05-01
The fiber bundle striations recognized clinically in normal monkey eyes appear to be bundles of axons compartmentalized within glial tunnels formed by Müller's-cell processes, when viewed histologically. The dark boundaries that separate individual bundles are the broadened foot endings of these cells near the inner surface of the retina. Within one week after focal retinal photocoagulation, characteristic fundus changes could be seen in experimental eyes. In histologic sections of the involved retina, there was marked cystic degeneration of the retinal nerve fiber layer. Within one month, atrophy of distal axon segments was complete. With the drop-out of damaged axons and thinning of individual fiber bundles, retinal striations became less prominent. The resulting fundus picture in these experimental eyes is similar to fiber bundle defects that can be seen clinically in various neuro-ophthalmic disorders.
Tangent bundle formulation of a charged gas
Sarbach, Olivier
2013-01-01
We discuss the relativistic kinetic theory for a simple, collisionless, charged gas propagating on an arbitrary curved spacetime geometry. Our general relativistic treatment is formulated on the tangent bundle of the spacetime manifold and takes advantage of its rich geometric structure. In particular, we point out the existence of a natural metric on the tangent bundle and illustrate its role for the development of the relativistic kinetic theory. This metric, combined with the electromagnetic field of the spacetime, yields an appropriate symplectic form on the tangent bundle. The Liouville vector field arises as the Hamiltonian vector field of a natural Hamiltonian. The latter also defines natural energy surfaces, called mass shells, which turn out to be smooth Lorentzian submanifolds. A simple, collisionless, charged gas is described by a distribution function which is defined on the mass shell and satisfies the Liouville equation. Suitable fibre integrals of the distribution function define observable fie...
Classical Higgs fields on gauge gluon bundles
Directory of Open Access Journals (Sweden)
Palese Marcella
2016-01-01
Full Text Available Classical Higgs fields and related canonical conserved quantities are defined by invariant variational problems on suitably defined gauge gluon bundles. We consider Lagrangian field theories which are assumed to be invariant with respect to the action of a gauge-natural group. As an illustrative example we exploit the ‘gluon Lagrangian’, i.e. a Yang-Mills Lagrangian on the (1, 1-order gauge-natural bundle of SU(3-principal connections. The kernel of the gauge-natural Jacobi morphism for such a Lagrangian, by inducing a reductive split structure, canonically defines a ‘gluon classical Higgs field’.
Abelian conformal field theory and determinant bundles
DEFF Research Database (Denmark)
Andersen, Jørgen Ellegaard; Ueno, K.
2007-01-01
Following [10], we study a so-called bc-ghost system of zero conformal dimension from the viewpoint of [14, 16]. We show that the ghost vacua construction results in holomorphic line bundles with connections over holomorphic families of curves. We prove that the curvature of these connections...... are up to a scale the same as the curvature of the connections constructed in [14, 16]. We study the sewing construction for nodal curves and its explicit relation to the constructed connections. Finally we construct preferred holomorphic sections of these line bundles and analyze their behaviour near...
Directory of Open Access Journals (Sweden)
Yubao Ma
2014-01-01
Full Text Available Purpose. The present study sought to determine the influences of single-bundle (SB, single-bundle augmentation (SBA, and double-bundle (DB reconstructions on balance ability and proprioceptive function. Methods. 67 patients who underwent a single- or double-bundle ACL reconstruction or a SBA using multistranded autologous hamstring tendons were included in this study with a 1-year follow-up. Body sway and knee kinesthesia (using the threshold to detect passive motion test (TTDPM were measured to indicate balance ability and proprioceptive function, respectively. Additionally, within-subject differences in anterior-posterior stability of the tibia and lower extremity muscle strength were evaluated before and after surgery. Results. At 6 and 12 months after surgery, DB reconstruction resulted in better balance and proprioceptive function than SB reconstruction (P<0.05. Although no significant difference was observed in balance ability or proprioceptive function between the SBA and DB reconstructions, knee stability was significantly better with SBA and DB reconstructions than SB reconstruction (P<0.05. No significant differences were found in quadriceps and hamstrings strength among the three reconstruction techniques. Conclusions. Our findings consider that joint stability, proprioceptive function, and balance ability were superior with SBA and DB reconstructions compared to SB reconstruction at 6 and 12 months after surgery.
Institute of Scientific and Technical Information of China (English)
无
1996-01-01
@@ The Zitongdong Block (Eastern Zitong Block) is located in the northwest of the Sichuan Basin. Tectonically, it is situated in the east part of Zitong Depression, southeast of mid-Longmenshan folded and faulted belt( as shown on Fig. 8 ), covering an area of 1 730 km2. The traffic is very convenient, the No. 108 national highway passes through the north of the block. Topographically, the area belongs to low hilly land at the elevation of 500-700 m.
Computations in intersection rings of flag bundles
Grayson, Daniel R; Stillman, Michael E
2012-01-01
Intersection rings of flag varieties and of isotropic flag varieties are generated by Chern classes of the tautological bundles modulo the relations coming from multiplicativity of total Chern classes. In this paper we describe the Groebner bases of the ideals of relations and give applications to computation of intersections, as implemented in Macaulay2.
Capacity efficiency of recovery request bundling
DEFF Research Database (Denmark)
Ruepp, Sarah Renée; Dittmann, Lars; Berger, Michael Stübert
2010-01-01
This paper presents a comparison of recovery methods in terms of capacity efficiency. In particular, a method where recovery requests are bundled towards the destination (Shortcut Span Protection) is evaluated against traditional recovery methods. Our simulation results show that Shortcut Span...... Protection uses more capacity than the unbundled related methods, but this is compensated by easier control and management of the recovery actions....
η-Invariant and Flat Vector Bundles
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
We present an alternate definition of the mod Z component of the AtiyahPatodi-Singer η invariant associated to (not necessary unitary) fiat vector bundles, which identifies explicitly its real and imaginary parts. This is done by combining a deformation of flat connections introduced in a previous paper with the analytic continuation procedure appearing in the original article of Atiyah, Parodi and Singer.
Lazarsfeld-Mukai bundles and applications
Aprodu, Marian
2012-01-01
We survey the development of the notion of Lazarsfeld-Mukai bundles together with various applications, from the classification of Mukai manifolds to Brill-Noether theory and syzygies of $K3$ sections. To see these techniques at work, we present a short proof of a result of M. Reid on the existence of elliptic pencils.
Meromorphic Higgs bundles And Related Geometries
Dalakov, Peter
2016-01-01
The present note is mostly a survey on the generalised Hitchin integrable system and moduli spaces of meromorphic Higgs bundles. We also fill minor gaps in the existing literature, outline a calculation of the infinitesimal period map and review briefly some related geometries.
Meromorphic Higgs bundles and related geometries
Dalakov, Peter
2016-11-01
The present note is mostly a survey on the generalised Hitchin integrable system and moduli spaces of meromorphic G-Higgs bundles. We also fill minor gaps in the existing literature, outline a calculation of the infinitesimal period map and review some related geometries.
The Hodge bundle on Hurwitz spaces
van der Geer, G.; Kouvidakis, A.
2011-01-01
In 2009 Kokotov, Korotkin and Zograf gave in [7] a formula for the class of the Hodge bundle on the Hurwitz space of admissible covers of genus g and degree d of the projective line. They gave an analytic proof of it. In this note we give an algebraic proof and an extension of the result.
Capacity efficiency of recovery request bundling
DEFF Research Database (Denmark)
Ruepp, Sarah Renée; Dittmann, Lars; Berger, Michael Stübert
2010-01-01
This paper presents a comparison of recovery methods in terms of capacity efficiency. In particular, a method where recovery requests are bundled towards the destination (Shortcut Span Protection) is evaluated against traditional recovery methods. Our simulation results show that Shortcut Span...
Active Hair-Bundle Motility by the Vertebrate Hair Cell
Tinevez, J.-Y.; Martin, P.; Jülicher, F.
2009-02-01
The hair bundle is both a mechano-sensory antenna and a force generator that might help the vertebrate hair cell from the inner ear to amplify its responsiveness to small stimuli. To study active hair-bundle motility, we combined calcium iontophoresis with mechanical stimulation of single hair bundles from the bullfrog's sacculus. A hair bundle could oscillate spontaneously, or be quiescent but display non-monotonic movements in response to abrupt force steps. Extracellular calcium changes or static biases to the bundle's position at rest could affect the kinetics of bundle motion and evoke transitions between the different classes of motility. The calcium-dependent location of a bundle's operating point within its nonlinear force-displacement relation controlled the type of movements observed. A unified theoretical description, in which mechanical activity stems from myosin-based adaptation and electro-mechanical feedback by Ca2+, could account for the fast and slow manifestations of active hair-bundle motility.
Institute of Scientific and Technical Information of China (English)
LIULUOFEI
1996-01-01
The author proves several embedding theorems for finite covering maps,principal G-bundies into bundles.The main results are 1. Let π：E→X be a finite covering map, and X a connected locally path-connected paracompact space. If cat X≤k, then the finite covering space π:E→X can be embedded into the trivial real k-plane bundle. 2. Let π：E→X be a principal G-bundle over a paracompact space. If there exists a linera action of Gon F(F=R or C)and cat X≤k ,then π：E→X can be embedded into ξ1 … ξn for any F-vector bundles ξi,i=1,…k.
Interplanetary Overlay Network Bundle Protocol Implementation
Burleigh, Scott C.
2011-01-01
The Interplanetary Overlay Network (ION) system's BP package, an implementation of the Delay-Tolerant Networking (DTN) Bundle Protocol (BP) and supporting services, has been specifically designed to be suitable for use on deep-space robotic vehicles. Although the ION BP implementation is unique in its use of zero-copy objects for high performance, and in its use of resource-sensitive rate control, it is fully interoperable with other implementations of the BP specification (Internet RFC 5050). The ION BP implementation is built using the same software infrastructure that underlies the implementation of the CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol (CFDP) built into the flight software of Deep Impact. It is designed to minimize resource consumption, while maximizing operational robustness. For example, no dynamic allocation of system memory is required. Like all the other ION packages, ION's BP implementation is designed to port readily between Linux and Solaris (for easy development and for ground system operations) and VxWorks (for flight systems operations). The exact same source code is exercised in both environments. Initially included in the ION BP implementations are the following: libraries of functions used in constructing bundle forwarders and convergence-layer (CL) input and output adapters; a simple prototype bundle forwarder and associated CL adapters designed to run over an IPbased local area network; administrative tools for managing a simple DTN infrastructure built from these components; a background daemon process that silently destroys bundles whose time-to-live intervals have expired; a library of functions exposed to applications, enabling them to issue and receive data encapsulated in DTN bundles; and some simple applications that can be used for system checkout and benchmarking.
Bundling Revisited: Substitute Products and Inter-Firm Discounts
Armstrong, Mark
2011-01-01
This paper extends the standard model of bundling to allow products to be substitutes and for products to be supplied by separate sellers. Whether integrated or separate, firms have an incentive to introduce bundling discounts when demand for the bundle is elastic relative to demand for stand-alone products. When products are partial substitutes, this typically gives an integrated firm a greater incentive to offer a bundle discount (relative to the standard model with additive preferences), w...
Holomorphic Vector Bundle on Hopf Manifolds with Abelian Fundamental Groups
Institute of Scientific and Technical Information of China (English)
Xiang Yu ZHOU; Wei Ming LIU
2004-01-01
Let X be a Hopf manifolds with an Abelian fundamental group. E is a holomorphic vector bundle of rank r with trivial pull-back to W = Cn - {0}. We prove the existence of a non-vanishing section of L(×) E for some line bundle on X and study the vector bundles filtration structure of E. These generalize the results of D. Mall about structure theorem of such a vector bundle E.
Yoo, Yon-Sik; Song, Si Young; Yang, Cheol Jung; Ha, Jong Mun; Kim, Yoon Sang
2016-01-01
Purpose The purpose of this study was to compare the clinical outcomes of arthroscopic anatomical double bundle (DB) anterior cruciate ligament (ACL) reconstruction with either selective anteromedial (AM) or posterolateral (PL) bundle reconstruction while preserving a relatively healthy ACL bundle. Materials and Methods The authors evaluated 98 patients with a mean follow-up of 30.8±4.0 months who had undergone DB or selective bundle ACL reconstructions. Of these, 34 cases underwent DB ACL reconstruction (group A), 34 underwent selective AM bundle reconstruction (group B), and 30 underwent selective PL bundle reconstructions (group C). These groups were compared with respect to Lysholm and International Knee Documentation Committee (IKDC) score, side-to-side differences of anterior laxity measured by KT-2000 arthrometer at 30 lbs, and stress radiography and Lachman and pivot shift test results. Pre- and post-operative data were objectively evaluated using a statistical approach. Results The preoperative anterior instability measured by manual stress radiography at 90° of knee flexion in group A was significantly greater than that in groups B and C (all pACL tears offers comparable clinical results to DB reconstruction in complete ACL tears. PMID:27401652
VECTOR BUNDLE, KILLING VECTOR FIELD AND PONTRYAGIN NUMBERS
Institute of Scientific and Technical Information of China (English)
周建伟
1991-01-01
Let E be a vector bundle over a compact Riemannian manifold M. We construct a natural metric on the bundle space E and discuss the relationship between the killing vector fields of E and M. Then we give a proof of the Bott-Baum-Cheeger Theorem for vector bundle E.
Heat exchanger with helical bundles of finned tubes
Energy Technology Data Exchange (ETDEWEB)
Eyking, H.J.
1975-01-23
The invention applies to a heat exchanger with helical bundles of tubes consisting of finned tubes separated by spacers. The spacers are designed as closed holding cylinders with holding devices for the tube bundles, each ot which surrounds a bundle of tubes. This construction serves to simplify the production process and to enable the use of the heat exchanger at higher loads.
Gauge bundles and Born-Infeld on the noncommutative torus
Hofman, C.; Verlinde, E.
1998-01-01
In this paper, we describe non-abelian gauge bundles with magnetic and electric uxes on higher dimensional noncomm utative tori. We give an explicit construction of a large class of bundles with nonzero magnetic 't Hooft uxes. W e discuss Morita equiv alence between these bundles. The action of
QTLs analysis of rice peduncle vascular bundle and panicle traits
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
@@The vascular bundle in plants plays an important role in transportation of photosynthetic products, mineral nutrients, water, and so on. Significant positive correlations were found between grain yield, panicle traits and the No. Of peduncle vascular bundles. So, it is very important to study the inheritance of peduncle vascular bundle, which is a quantitative trait.
Stability of Picard Bundle Over Moduli Space of Stable Vector Bundles of Rank Two Over a Curve
Indian Academy of Sciences (India)
Indranil Biswas; Tomás L Gómez
2001-08-01
Answering a question of [BV] it is proved that the Picard bundle on the moduli space of stable vector bundles of rank two, on a Riemann surface of genus at least three, with fixed determinant of odd degree is stable.
Reflood experiments in rod bundles with flow blockages due to clad ballooning
Energy Technology Data Exchange (ETDEWEB)
Moon, S.K.; Kim, J.; Kim, K.; Kim, B.J.; Park, J.K.; Youn, Y.J.; Choi, H.S.; Song, C.H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2016-07-15
Clad ballooning and the resulting partial flow blockage are one of the major thermal-hydraulic concerns associated with the coolability of partially blocked cores during a loss-of-coolant accident (LOCA). Several in-pile tests have shown that fuel relocation causes a local power accumulation and a high thermal coupling between the clad and fuel debris in the ballooned regions. However, previous experiments in the 1980s did not take into account the fuel relocation phenomena and resulting local power increase in the ballooned regions. The present paper presents the results of systematic investigations on the coolability of rod bundles with flow blockages. The experiments were mainly performed in 5 x 5 rod bundles, 2 x 2 rod bundles and other test facilities. The experiments include a reflood heat transfer, single-phase convective heat transfer, flow redistributions phenomena, and droplet break-up behavior. The effects of the fuel relocation and resulting local power increase were investigated using a 5 x 5 rod bundle. The fuel relocation phenomena increase the peak cladding temperature.
Institute of Scientific and Technical Information of China (English)
无
1996-01-01
@@ Zitongxi Block (Western Zitong Block), is located in Zitong County, northwest of Sichuan Province (as shown on Fig. 8 ). Geologically. it is situated in the Zitong Depression, southwest of the middle Longmenshan faulted and folded belt, covering an area of 1 830 km2. Transportation is very convenient. A crisscross network of highways run through the block and the Baocheng railway is nearby. The climate is moderate. Most area belongs to hilly land with the elevation of 500-600 m.The Tongjiang River runs across the area.
Productivity and costs of slash bundling in Nordic conditions
Energy Technology Data Exchange (ETDEWEB)
Kaerhae, K.; Vartiamaeki, T. [Metsaeteho Oy, P.O. Box 101, FI-00171 Helsinki (Finland)
2006-12-15
The number of slash bundlers and the volume of slash bundling have been rapidly increasing during the last few years in Finland. However, no comprehensive time or follow-up studies have been carried out on slash bundling technology in Finland or in any other country. Metsateho Oy carried out studies on the productivity and costs of slash bundling in different Nordic recovering conditions. The study methods included both time and follow-up studies. Data were collected during the summer and winter period primarily in Norway spruce (Picea abies L. Karst.) dominated clear cutting sites. The bundling techniques performed by different types of bundler (Fiberpac 370, Timberjack 1490D, Pika RS 2000, Valmet WoodPac) were studied. The average productivity of slash bundling was 18.1 bundles per operating (E{sub 15}, including delays shorter than 15min) hour with the Timberjack 1490D and Fiberpac 370 bundlers in the follow-up study. The operator of the slash bundler had the greatest effect on the productivity of bundling. The prerequisite for increased bundling volumes is a reduction in the costs of the most expensive sub-stage of the bundling supply chain, i.e. bundling itself. This requires improved recovery conditions at bundling sites, increased bundling productivity, larger sized bundles, and the execution of bundling operations in two work shifts using an efficient bundler and effective operator working methods. Implementation of these development measures will bring the bundling supply chain up to a speed that makes it the most competitive supply chain for forest chips in terms of total supply costs for long-distance transportation distances of more than 60km. (author)
Energy Technology Data Exchange (ETDEWEB)
Kaipainen, H.; Seppaenen, V.; Rinne, S.
1996-12-31
The conditions on which the bundling of the harvesting residues from spruce regeneration fellings would become profitable were studied. The calculations showed that one of the most important features was sufficient compaction of the bundle, so that the portion of the wood in the unit volume of the bundle has to be more than 40 %. The tests showed that the timber grab loader of farm tractor was insufficient for production of dense bundles. The feeding and compression device of the prototype bundler was constructed in the research and with this device the required density was obtained.The rate of compaction of the dry spruce felling residues was about 40 % and that of the fresh residues was more than 50 %. The comparison between the bundles showed that the calorific value of the fresh bundle per unit volume was nearly 30 % higher than that of the dry bundle. This means that the treatment of the bundles should be done of fresh felling residues. Drying of the bundles succeeded well, and the crushing and chipping tests showed that the processing of the bundles at the plant is possible. The treatability of the bundles was also excellent. By using the prototype, developed in the research, it was possible to produce a bundle of the fresh spruce harvesting residues, the diameter of which was about 50 cm and the length about 3 m, and the rate of compaction over 50 %. By these values the reduction target of the costs is obtainable
Institute of Scientific and Technical Information of China (English)
无
1996-01-01
@@ Chengzikou Block is located in the north of Hekou district, Dongying City, Shandong Province, adjacent to Bohai Bay. It can be geographically divided into three units: onshore, transitional zone and offshore ultrashallow zone, totally covering an area of 470 km2. The southern onshore area is low and gentle in topography;the northern shallow sea is at water depths of 2-8 m below sea level, and the transitional zone occupies more than 60% of the whole block. The climate belongs to temperate zone with seasonal wind. Highways are welldeveloped here, and the traffic is very convenient. The Chengzikou Block is about 80 km away from Dongying City and 290 km from Jinan City in the south. The northern offshore area of the block is 160 km away from Longkou port in the east and only 38 km away in the west from Zhuangxi port.
Institute of Scientific and Technical Information of China (English)
无
1996-01-01
@@ Longmenshan Block is located in Jiange County of Jiangyou City in the northwest of Sichuan Basin. covering an area of 2 628 km2. Geologically, it is situated in the Mid-Longmenshan fault and fold belt, neighbouring Zitong Depression in its southeast. There are mountains surrounding its northwest , the rest area being hilly land,with the elevation of 500-700 m. The BaoCheng railway and the No. 108 highway run through the block, the traffic is very convenient.
Phase Slips in Oscillatory Hair Bundles
Roongthumskul, Yuttana; Shlomovitz, Roie; Bruinsma, Robijn; Bozovic, Dolores
2013-01-01
Hair cells of the inner ear contain an active amplifier that allows them to detect extremely weak signals. As one of the manifestations of an active process, spontaneous oscillations arise in fluid immersed hair bundles of in vitro preparations of selected auditory and vestibular organs. We measure the phase-locking dynamics of oscillatory bundles exposed to low-amplitude sinusoidal signals, a transition that can be described by a saddle-node bifurcation on an invariant circle. The transition is characterized by the occurrence of phase slips, at a rate that is dependent on the amplitude and detuning of the applied drive. The resultant staircase structure in the phase of the oscillation can be described by the stochastic Adler equation, which reproduces the statistics of phase slip production. PMID:25167040
Care bundles reduce readmissions for COPD.
Matthews, Healther; Tooley, Cathy; Nicholls, Carol; Lindsey-Halls, Anna
In 2011, the respiratory nursing team at the James Paget University Hospital Foundation Trust were considering introducing a discharge care bundle for patients admitted with an acute exacerbation of chronic obstructive pulmonary disease. At the same time, the trust was asking for applications for Commissioning for Quality and Innovation schemes (CQUINs). These are locally agreed packages of quality improvement goals and indicators, which, if achieved in total, enable the provider to earn its full CQUIN payment. A CQUIN scheme should address the three domains of quality, safety and effectiveness, patient experience and also show innovation. This article discusses how the care bundle was introduced and how, over a 12-month period, it showed tangible results in improving the care pathway for COPD patients as well as reducing readmissions and saving a significant amount of money.
Muñoz, C Sánchez; Del Valle, E; Tudela, A González; Müller, K; Lichtmannecker, S; Kaniber, M; Tejedor, C; Finley, J J; Laussy, F P
2014-07-01
Controlling the ouput of a light emitter is one of the basic tasks of photonics, with landmarks such as the laser and single-photon sources. The development of quantum applications makes it increasingly important to diversify the available quantum sources. Here, we propose a cavity QED scheme to realize emitters that release their energy in groups, or "bundles" of N photons, for integer N. Close to 100% of two-photon emission and 90% of three-photon emission is shown to be within reach of state of the art samples. The emission can be tuned with system parameters so that the device behaves as a laser or as a N-photon gun. The theoretical formalism to characterize such emitters is developed, with the bundle statistics arising as an extension of the fundamental correlation functions of quantum optics. These emitters will be useful for quantum information processing and for medical applications.
Client Provider Collaboration for Service Bundling
Directory of Open Access Journals (Sweden)
LETIA, I. A.
2008-04-01
Full Text Available The key requirement for a service industry organization to reach competitive advantages through product diversification is the existence of a well defined method for building service bundles. Based on the idea that the quality of a service or its value is given by the difference between expectations and perceptions, we draw the main components of a frame that aims to support the client and the provider agent in an active collaboration meant to co-create service bundles. Following e3-value model, we structure the supporting knowledge around the relation between needs and satisfying services. We deal with different perspectives about quality through an ontological extension of Value Based Argumentation. The dialog between the client and the provider takes the form of a persuasion whose dynamic object is the current best configuration. Our approach for building service packages is a demand driven approach, allowing progressive disclosure of private knowledge.
Non-abelian higher gauge theory and categorical bundle
Viennot, David
2016-12-01
A gauge theory is associated with a principal bundle endowed with a connection permitting to define horizontal lifts of paths. The horizontal lifts of surfaces cannot be defined into a principal bundle structure. An higher gauge theory is an attempt to generalize the bundle structure in order to describe horizontal lifts of surfaces. A such attempt is particularly difficult for the non-abelian case. Some structures have been proposed to realize this goal (twisted bundle, gerbes with connection, bundle gerbe, 2-bundle). Each of them uses a category in place of the total space manifold of the usual principal bundle structure. Some of them replace also the structure group by a category (more precisely a Lie crossed module viewed as a category). But the base space remains still a simple manifold (possibly viewed as a trivial category with only identity arrows). We propose a new principal categorical bundle structure, with a Lie crossed module as structure groupoid, but with a base space belonging to a bigger class of categories (which includes non-trivial categories), that we called affine 2-spaces. We study the geometric structure of the categorical bundles built on these categories (which are a more complicated structure than the 2-bundles) and the connective structures on these bundles. Finally we treat an example interesting for quantum dynamics which is associated with the Bloch wave operator theory.
Quantum principal bundles and their characteristic classes
Durdevic, M
1996-01-01
A brief exposition of the general theory of characteristic classes of quantum principal bundles is given. The theory of quantum characteristic classes incorporates ideas of classical Weil theory into the conceptual framework of non-commutative differential geometry. A purely cohomological interpretation of the Weil homomorphism is given, together with a standard geometrical interpretation via quantum invariant polynomials. A natural spectral sequence is described. Some quantum phenomena appearing in the formalism are discussed.
Uncovering ecosystem service bundles through social preferences.
Directory of Open Access Journals (Sweden)
Berta Martín-López
Full Text Available Ecosystem service assessments have increasingly been used to support environmental management policies, mainly based on biophysical and economic indicators. However, few studies have coped with the social-cultural dimension of ecosystem services, despite being considered a research priority. We examined how ecosystem service bundles and trade-offs emerge from diverging social preferences toward ecosystem services delivered by various types of ecosystems in Spain. We conducted 3,379 direct face-to-face questionnaires in eight different case study sites from 2007 to 2011. Overall, 90.5% of the sampled population recognized the ecosystem's capacity to deliver services. Formal studies, environmental behavior, and gender variables influenced the probability of people recognizing the ecosystem's capacity to provide services. The ecosystem services most frequently perceived by people were regulating services; of those, air purification held the greatest importance. However, statistical analysis showed that socio-cultural factors and the conservation management strategy of ecosystems (i.e., National Park, Natural Park, or a non-protected area have an effect on social preferences toward ecosystem services. Ecosystem service trade-offs and bundles were identified by analyzing social preferences through multivariate analysis (redundancy analysis and hierarchical cluster analysis. We found a clear trade-off among provisioning services (and recreational hunting versus regulating services and almost all cultural services. We identified three ecosystem service bundles associated with the conservation management strategy and the rural-urban gradient. We conclude that socio-cultural preferences toward ecosystem services can serve as a tool to identify relevant services for people, the factors underlying these social preferences, and emerging ecosystem service bundles and trade-offs.
Uncontrolled inexact information within bundle methods
Malick, Jérôme; Welington De Oliveira, ·; Zaourar-Michel, Sofia
2016-01-01
International audience; We consider convex nonsmooth optimization problems where additional information with uncontrolled accuracy is readily available. It is often the case when the objective function is itself the output of an optimization solver, as for large-scale energy optimization problems tackled by decomposition. In this paper, we study how to incorporate the uncontrolled linearizations into (proximal and level) bundle algorithms in view of generating better iterates and possibly acc...
On Complex Supermanifolds with Trivial Canonical Bundle
Groeger, Josua
2016-01-01
We give an algebraic characterisation for the triviality of the canonical bundle of a complex supermanifold in terms of a certain Batalin-Vilkovisky superalgebra structure. As an application, we study the Calabi-Yau case, in which an explicit formula in terms of the Levi-Civita connection is achieved. Our methods include the use of complex integral forms and the recently developed theory of superholonomy.
Uncovering Ecosystem Service Bundles through Social Preferences
Martín-López, Berta; Iniesta-Arandia, Irene; García-Llorente, Marina; Palomo, Ignacio; Casado-Arzuaga, Izaskun; Amo, David García Del; Gómez-Baggethun, Erik; Oteros-Rozas, Elisa; Palacios-Agundez, Igone; Willaarts, Bárbara; González, José A.; Santos-Martín, Fernando; Onaindia, Miren; López-Santiago, Cesar; Montes, Carlos
2012-01-01
Ecosystem service assessments have increasingly been used to support environmental management policies, mainly based on biophysical and economic indicators. However, few studies have coped with the social-cultural dimension of ecosystem services, despite being considered a research priority. We examined how ecosystem service bundles and trade-offs emerge from diverging social preferences toward ecosystem services delivered by various types of ecosystems in Spain. We conducted 3,379 direct face-to-face questionnaires in eight different case study sites from 2007 to 2011. Overall, 90.5% of the sampled population recognized the ecosystem’s capacity to deliver services. Formal studies, environmental behavior, and gender variables influenced the probability of people recognizing the ecosystem’s capacity to provide services. The ecosystem services most frequently perceived by people were regulating services; of those, air purification held the greatest importance. However, statistical analysis showed that socio-cultural factors and the conservation management strategy of ecosystems (i.e., National Park, Natural Park, or a non-protected area) have an effect on social preferences toward ecosystem services. Ecosystem service trade-offs and bundles were identified by analyzing social preferences through multivariate analysis (redundancy analysis and hierarchical cluster analysis). We found a clear trade-off among provisioning services (and recreational hunting) versus regulating services and almost all cultural services. We identified three ecosystem service bundles associated with the conservation management strategy and the rural-urban gradient. We conclude that socio-cultural preferences toward ecosystem services can serve as a tool to identify relevant services for people, the factors underlying these social preferences, and emerging ecosystem service bundles and trade-offs. PMID:22720006
Uncovering ecosystem service bundles through social preferences
Berta Martín-López; Irene Iniesta-Arandia; Marina García-Llorente; Ignacio Palomo; Izaskun Casado-Arzuaga; David García Del Amo; Erik Gómez-Baggethun; Elisa Oteros-Rozas; Igone Palacios-Agundez; Bárbara Willaarts; González, José A.; Fernando Santos-Martín; Miren Onaindia; Cesar López-Santiago; Carlos Montes
2012-01-01
11 p. Ecosystem service assessments have increasingly been used to support environmental management policies, mainly based on biophysical and economic indicators. However, few studies have coped with the social-cultural dimension of ecosystem services, despite being considered a research priority. We examined how ecosystem service bundles and trade-offs emerge from diverging social preferences toward ecosystem services delivered by various types of ecosystems in Spain. We conducted 3,379 d...
Deformations of Fell bundles and twisted graph algebras
Raeburn, Iain
2016-11-01
We consider Fell bundles over discrete groups, and the C*-algebra which is universal for representations of the bundle. We define deformations of Fell bundles, which are new Fell bundles with the same underlying Banach bundle but with the multiplication deformed by a two-cocycle on the group. Every graph algebra can be viewed as the C*-algebra of a Fell bundle, and there are are many cocycles of interest with which to deform them. We thus obtain many of the twisted graph algebras of Kumjian, Pask and Sims. We demonstate the utility of our approach to these twisted graph algebras by proving that the deformations associated to different cocycles can be assembled as the fibres of a C*-bundle.
Bundling harvester; Harvennuspuun automaattisen nippukorjausharvesterin kehittaeminen
Energy Technology Data Exchange (ETDEWEB)
Koponen, K. [Eko-Log Oy, Kuopio (Finland)
1997-12-01
The starting point of the project was to design and construct, by taking the silvicultural point of view into account, a harvesting and processing system especially for energy-wood, containing manually driven bundling harvester, automating of the harvester, and automated loading. The equipment forms an ideal method for entrepreneur`s-line harvesting. The target is to apply the system also for owner`s-line harvesting. The profitability of the system promotes the utilisation of the system in both cases. The objectives of the project were: to construct a test equipment and prototypes for all the project stages, to carry out terrain and strain tests in order to examine the usability and durability, as well as the capacity of the machine, to test the applicability of the Eko-Log system in simultaneous harvesting of energy and pulp woods, and to start the marketing and manufacturing of the products. The basic problems of the construction of the bundling harvester have been solved using terrain-tests. The prototype machine has been shown to be operable. Loading of the bundles to form sufficiently economically transportable loads has been studied, and simultaneously, the branch-biomass has been tried to be utilised without loosing the profitability of transportation. The results have been promising, and will promote the profitable utilisation of wood-energy. (orig.)
Development of Strengthened Bundle High Temperature Superconductors
Energy Technology Data Exchange (ETDEWEB)
Lue, J.W.; Lubell, M.S. [Oak Ridge National Lab., TN (United States); Demko, J.A. [Oak Ridge Inst. for Science and Education, TN (United States); Tomsic, M. [Plastronic, Inc., Troy, OH (United States); Sinha, U. [Southwire Company, Carollton, GA (United States)
1997-12-31
In the process of developing high temperature superconducting (HTS) transmission cables, it was found that mechanical strength of the superconducting tape is the most crucial property that needs to be improved. It is also desirable to increase the current carrying capacity of the conductor so that fewer layers are needed to make the kilo-amp class cables required for electric utility usage. A process has been developed by encapsulating a stack of Bi-2223/Ag tapes with a silver or non-silver sheath to form a strengthened bundle superconductor. This process was applied to HTS tapes made by the Continuous Tube Forming and Filling (CTFF) technique pursued by Plastronic Inc. and HTS tapes obtained from other manufacturers. Conductors with a bundle of 2 to 6 HTS tapes have been made. The bundled conductor is greatly strengthened by the non-silver sheath. No superconductor degradation as compared to the sum of the original critical currents of the individual tapes was seen on the finished conductors.
An analytical fiber bundle model for pullout mechanics of root bundles
Cohen, D.; Schwarz, M.; Or, D.
2011-09-01
Roots in soil contribute to the mechanical stability of slopes. Estimation of root reinforcement is challenging because roots form complex biological networks whose geometrical and mechanical characteristics are difficult to characterize. Here we describe an analytical model that builds on simple root descriptors to estimate root reinforcement. Root bundles are modeled as bundles of heterogeneous fibers pulled along their long axes neglecting root-soil friction. Analytical expressions for the pullout force as a function of displacement are derived. The maximum pullout force and corresponding critical displacement are either derived analytically or computed numerically. Key model inputs are a root diameter distribution (uniform, Weibull, or lognormal) and three empirical power law relations describing tensile strength, elastic modulus, and length of roots as functions of root diameter. When a root bundle with root tips anchored in the soil matrix is pulled by a rigid plate, a unique parameter, ?, that depends only on the exponents of the power law relations, dictates the order in which roots of different diameters break. If ? 1, large roots break first. When ? = 1, all fibers break simultaneously, and the maximum tensile force is simply the roots' mean force times the number of roots in the bundle. Based on measurements of root geometry and mechanical properties, the value of ? is less than 1, usually ranging between 0 and 0.7. Thus, small roots always fail first. The model shows how geometrical and mechanical characteristics of roots and root diameter distribution affect the pullout force, its maximum and corresponding displacement. Comparing bundles of roots that have similar mean diameters, a bundle with a narrow variance in root diameter will result in a larger maximum force and a smaller displacement at maximum force than a bundle with a wide diameter distribution. Increasing the mean root diameter of a bundle without changing the distribution's shape increases
Sankararamakrishnan, R; Sansom, M S
1995-11-01
The transbilayer pore of the nicotinic acetylcholine receptor (nAChR) is formed by a pentameric bundle of M2 helices. Models of pentameric bundles of M2 helices have been generated using simulated annealing via restrained molecular dynamics. The influence of: (a) the initial C alpha template; and (b) screening of sidechain electrostatic interactions on the geometry of the resultant M2 helix bundles is explored. Parallel M2 helices, in the absence of sidechain electrostatic interactions, pack in accordance with simple ridges-in-grooves considerations. This results in a helix crossing angle of ca. +12 degrees, corresponding to a left-handed coiled coil structure for the bundle as a whole. Tilting of M2 helices away from the central pore axis at their C-termini and/or inclusion of sidechain electrostatic interactions may perturb such ridges-in-grooves packing. In the most extreme cases right-handed coiled coils are formed. An interplay between inter-helix H-bonding and helix bundle geometry is revealed. The effects of changes in electrostatic screening on the dimensions of the pore mouth are described and the significance of these changes in the context of models for the nAChR pore domain is discussed.
Treatment of ras-induced cancers by the F-actin-bundling drug MKT-077.
Tikoo, A; Shakri, R; Connolly, L; Hirokawa, Y; Shishido, T; Bowers, B; Ye, L H; Kohama, K; Simpson, R J; Maruta, H
2000-01-01
A rhodacyanine dye called MKT-077 has shown a highly selective toxicity toward several distinct human malignant cell lines, including bladder carcinoma EJ, and has been subjected to clinical trials for cancer therapy. In the pancreatic carcinoma cell line CRL-1420, but not in normal African green monkey kidney cell line CV-1, it is selectively accumulated in mitochondria. However, both the specific oncogenes responsible for its selective toxicity toward cancer cells, and its target proteins in these cancer cells, still remain to be determined. This study was conducted using normal and ras-transformed NIH 3T3 fibroblasts to determine whether oncogenic ras mutants such as v-Ha-ras are responsible for the selective toxicity of MKT-077 and also to identify its targets, using its derivative called "compound 1" as a specific ligand. We have found that v-Ha-ras is responsible for the selective toxicity of MKT-077 in both in vitro and in vivo. Furthermore, we have identified and affinity purified at least two distinct proteins of 45 kD (p45) and 75 kD (p75), which bind MKT-077 in v-Ha-ras-transformed cells but not in parental normal cells. Microsequencing analysis has revealed that the p45 is a mixture of beta- and gamma-actin, whereas the p75 is HSC70, a constitutive member of the Hsp70 heat shock adenosine triphosphatase family, which inactivates the tumor suppressor p53. MKT-077 binds actin directly, bundles actin filaments by cross-linking, and blocks membrane ruffling. Like a few F-actin-bundling proteins such as HS1, alpha-actinin, and vinculin as well as F-actin cappers such as tensin and chaetoglobosin K (CK), the F-actin-bundling drug MKT-077 suppresses ras transformation by blocking membrane ruffling. These findings suggest that other selective F-actin-bundling/capping compounds are also potentially useful for the chemotherapy of ras-associated cancers.
Institute of Scientific and Technical Information of China (English)
无
1996-01-01
@@ The Chadong Block, located in the east of Qaidam Basin, Qinghai Province, covers an area of 12 452 km2. It is bounded by Kunlum Mountains in the south and the northwest is closely adjacent to Aimunike Mountain.Rivers are widely distributed, which always run in NWSE direction, including the Sulunguole, Qaidam and Haluwusu Rivers. The traffic condition is good, the Qinghai-Tibet highway stretching through the whole area and the Lan-Qing railway, 20-50 km away from the block, passing from north to west. A lot of Mongolia minority people have settled there, of which herdsmen always live nearby the Qaidam River drainage area.
An Alternative Bundle-to-Bundle Suturing Technique for Repairing Fresh Achilles Tendon Rupture.
Zhao, Jingjing; Yu, Bin; Xie, Ming; Huang, Ruokun; Xiao, Kai
2016-01-01
The main concern about conventional Achilles tendon repair surgical techniques is how to maintain the initial strength of the ruptured Achilles tendon through complicated suturing methods. The primary surgical problem lies in the properties of the soft tissue; the deterioration of the Achilles tendon, especially in its elasticity; and the surface lubricity of the local tissues. In the present study, we describe an innovative bundle-to-bundle suturing method that addresses these potential problems. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.
Phase 4 paroxysmal AV block in a patient with scleroderma.
Butschek, Ross; Powell, Brian D; Littmann, Laszlo
2013-01-01
A 72-year-old man with limited cutaneous systemic scleroderma was hospitalized for two episodes of witnessed syncope. The baseline 12-lead electrocardiogram was normal but on telemetry there were numerous episodes of paroxysmal AV block with asystolic periods of up to 7.5 s duration. Analysis of the rhythm strips revealed phase 4 intra-His bundle block characterized by critical P-P intervals that triggered the AV block, and a narrow range of junctional escape to subsequent P wave intervals that were required to release the AV block. A dual chamber pacemaker was implanted. Copyright © 2013 Elsevier Inc. All rights reserved.
Amplitude death of coupled hair bundles with stochastic channel noise
Kim, Kyung-Joong
2014-01-01
Hair cells conduct auditory transduction in vertebrates. In lower vertebrates such as frogs and turtles, due to the active mechanism in hair cells, hair bundles(stereocilia) can be spontaneously oscillating or quiescent. Recently, the amplitude death phenomenon has been proposed [K.-H. Ahn, J. R. Soc. Interface, {\\bf 10}, 20130525 (2013)] as a mechanism for auditory transduction in frog hair-cell bundles, where sudden cessation of the oscillations arises due to the coupling between non-identical hair bundles. The gating of the ion channel is intrinsically stochastic due to the stochastic nature of the configuration change of the channel. The strength of the noise due to the channel gating can be comparable to the thermal Brownian noise of hair bundles. Thus, we perform stochastic simulations of the elastically coupled hair bundles. In spite of stray noisy fluctuations due to its stochastic dynamics, our simulation shows the transition from collective oscillation to amplitude death as inter-bundle coupling str...
Monopoles and Modifications of Bundles over Elliptic Curves
Directory of Open Access Journals (Sweden)
Andrey M. Levin
2009-06-01
Full Text Available Modifications of bundles over complex curves is an operation that allows one to construct a new bundle from a given one. Modifications can change a topological type of bundle. We describe the topological type in terms of the characteristic classes of the bundle. Being applied to the Higgs bundles modifications establish an equivalence between different classical integrable systems. Following Kapustin and Witten we define the modifications in terms of monopole solutions of the Bogomolny equation. We find the Dirac monopole solution in the case R × (elliptic curve. This solution is a three-dimensional generalization of the Kronecker series. We give two representations for this solution and derive a functional equation for it generalizing the Kronecker results. We use it to define Abelian modifications for bundles of arbitrary rank. We also describe non-Abelian modifications in terms of theta-functions with characteristic.
A Tannakian approach to dimensional reduction of principal bundles
Álvarez-Cónsul, Luis; García-Prada, Oscar
2016-01-01
Let $P$ be a parabolic subgroup of a connected simply connected complex semisimple Lie group $G$. Given a compact K\\"ahler manifold $X$, the dimensional reduction of $G$-equivariant holomorphic vector bundles over $X\\times G/P$ was carried out by the first and third authors. This raises the question of dimensional reduction of holomorphic principal bundles over $X\\times G/P$. The method used for equivariant vector bundles does not generalize to principal bundles. In this paper, we adapt to equivariant principal bundles the Tannakian approach of Nori, to describe the dimensional reduction of $G$-equivariant principal bundles over $X\\times G/P$, and to establish a Hitchin--Kobayashi type correspondence. In order to be able to apply the Tannakian theory, we need to assume that $X$ is a complex projective manifold.
The avalanche process of the fiber bundle model with defect
Hao, Da-Peng; Tang, Gang; Xia, Hui; Xun, Zhi-Peng; Han, Kui
2017-04-01
In order to explore the impacts of defect on the tensile fracture process of materials, the fiber bundle model with defect is constructed based on the classical fiber bundle model. In the fiber bundle model with defect, the two key parameters are the mean size and the density of defects. In both uniform and Weibull threshold distributions, the mean size and density all bring impacts on the threshold distribution of fibers. By means of analytical approximation and numerical simulation, we show that the two key parameters of the model have substantial effects on the failure process of the bundle. From macroscopic view, the defect described by the altering of threshold distribution of fibers will has a significant impact on the mechanical properties of the bundle. While in microscopic scale, the statistical properties of the model are still harmonious with the classical fiber bundle model.
Cosmic multimuon bundles detected by DELPHI
Rídky, J
2004-01-01
The DELPHI detector located at LEP accelerator has been used also to measure multimuon bundles originated from cosmic ray interactions. Two subdetectors-hadron calorimeter and time projection chamber, are used for this purpose. The 1999 and 2000 data are analyzed over wide range of multiplicities. The multiplicity distribution is compared with prediction of Monte Carlo simulation based on CORSIKA/QGSJET. The Monte-Carlo does not describe the large multiplicity part of data. Even the extreme assumption on the cosmic ray composition (pure iron nuclei) hardly predicts comparable number of high-multiplicity events.
Differential geometry of complex vector bundles
Kobayashi, Shoshichi
2014-01-01
Holomorphic vector bundles have become objects of interest not only to algebraic and differential geometers and complex analysts but also to low dimensional topologists and mathematical physicists working on gauge theory. This book, which grew out of the author's lectures and seminars in Berkeley and Japan, is written for researchers and graduate students in these various fields of mathematics. Originally published in 1987. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeto
Higher order mechanics on graded bundles
Bruce, Andrew James; Grabowska, Katarzyna; Grabowski, Janusz
2015-05-01
In this paper we develop a geometric approach to higher order mechanics on graded bundles in both, the Lagrangian and Hamiltonian formalism, via the recently discovered weighted algebroids. We present the corresponding Tulczyjew triple for this higher order situation and derive in this framework the phase equations from an arbitrary (also singular) Lagrangian or Hamiltonian, as well as the Euler-Lagrange equations. As important examples, we geometrically derive the classical higher order Euler-Lagrange equations and analogous reduced equations for invariant higher order Lagrangians on Lie groupoids.
Bundling Products and Services Through Modularization Strategies
DEFF Research Database (Denmark)
Bask, Anu; Hsuan, Juliana; Rajahonka, Mervi;
2012-01-01
Modularity has been recognized as a powerful tool in improving the efficiency and management of product design and manufacturing. However, the integrated view on covering both, product and service modularity for product-service systems (PSS), is under researched. Therefore, in this paper our...... objective is to contribute to the PSS modularity. Thus, we describe configurations of PSSs and the bundling of products and services through modularization strategies. So far there have not been tools to analyze and determine the correct combinations of degrees of product and service modularities....
Compression of a bundle of light rays.
Marcuse, D
1971-03-01
The performance of ray compression devices is discussed on the basis of a phase space treatment using Liouville's theorem. It is concluded that the area in phase space of the input bundle of rays is determined solely by the required compression ratio and possible limitations on the maximum ray angle at the output of the device. The efficiency of tapers and lenses as ray compressors is approximately equal. For linear tapers and lenses the input angle of the useful rays must not exceed the compression ratio. The performance of linear tapers and lenses is compared to a particular ray compressor using a graded refractive index distribution.
Vector bundles on complex projective spaces
Okonek, Christian; Spindler, Heinz
1980-01-01
This expository treatment is based on a survey given by one of the authors at the Séminaire Bourbaki in November 1978 and on a subsequent course held at the University of Göttingen. It is intended to serve as an introduction to the topical question of classification of holomorphic vector bundles on complex projective spaces, and can easily be read by students with a basic knowledge of analytic or algebraic geometry. Short supplementary sections describe more advanced topics, further results, and unsolved problems.
Heat transfer in bundles of finned tubes in crossflow
Energy Technology Data Exchange (ETDEWEB)
Stasiulevicius, J.; Skrinska, A.; Zukauskas, A.; Hewitt, G.F.
1986-01-01
This book provides correlations of heat transfer and hydraulic data for bundles of finned tubes in crossflow at high Reynolds numbers. Results of studies of the effectiveness of the fin, local, and mean heat transfer coefficients are presented. The effect of geometric parameters of the fins and of the location of tubes in the bundle on heat transfer and hydraulic drag are described. The resistance of the finned tube bundles under study and other factors are examined.
Coolability of ballooned VVER bundles with pellet relocation
Energy Technology Data Exchange (ETDEWEB)
Hozer, Z.; Nagy, I.; Windberg, P.; Vimi, A. [AEKI, P.O.box 49, Budapest, H-1525 (Hungary)
2009-06-15
During a LOCA incident the high pressure in the fuel rods can lead to clad ballooning and the debris of fuel pellets can fill the enlarged volume. The evaluation of the role of these two effects on the coolability of VVER type fuel bundles was the main objective of the experimental series. The tests were carried out in the modified configuration of the CODEX facility. 19-rod electrically heated VVER type bundle was used. The test section was heated up to 600 deg. C in steam atmosphere and the bundle was quenched from the bottom by cold water. Three series of tests were performed: 1. Reference bundle with fuel rods without ballooning, with uniform power profile. 2. Bundle with 86% blockage rate and with uniform power profile. The blockage rate was reached by superimposing hollow sleeves on all 19 fuel rods. 3. Bundle with 86% blockage rate and with local power peak in the ballooned area. The local power peak was produced by the local reduction the cross section of the internal heater bar inside of the fuel rods. In all three bundle configurations three different cooling water flow-rates were applied. The experimental results confirmed that a VVER bundle with even 86% blockage rate remains coolable after a LOCA event. The ballooned section creates some obstacles for the cooling water during reflood of the bundle, but this effect causes only a short delay in the cooling down of the hot fuel rods. Earlier tests on the coolability of ballooned bundles were performed only with Western type bundles with square fuel lattice. The present test series was the first confirmation of the coolability of VVER type bundles with triangular lattice. The accumulation of fuel pellet debris in the ballooned volume results in a local power peak, which leads to further slowing down of quench front. The first tests indicated that the effect of local power peak was less significant on the delay of cooling down than the effect of ballooning. (authors)
Heat Transfer Analysis in Wire Bundles for Aerospace Vehicles
Rickman, S. L.; Iamello, C. J.
2016-01-01
Design of wiring for aerospace vehicles relies on an understanding of "ampacity" which refers to the current carrying capacity of wires, either, individually or in wire bundles. Designers rely on standards to derate allowable current flow to prevent exceedance of wire temperature limits due to resistive heat dissipation within the wires or wire bundles. These standards often add considerable margin and are based on empirical data. Commercial providers are taking an aggressive approach to wire sizing which challenges the conventional wisdom of the established standards. Thermal modelling of wire bundles may offer significant mass reduction in a system if the technique can be generalized to produce reliable temperature predictions for arbitrary bundle configurations. Thermal analysis has been applied to the problem of wire bundles wherein any or all of the wires within the bundle may carry current. Wire bundles present analytical challenges because the heat transfer path from conductors internal to the bundle is tortuous, relying on internal radiation and thermal interface conductance to move the heat from within the bundle to the external jacket where it can be carried away by convective and radiative heat transfer. The problem is further complicated by the dependence of wire electrical resistivity on temperature. Reduced heat transfer out of the bundle leads to higher conductor temperatures and, hence, increased resistive heat dissipation. Development of a generalized wire bundle thermal model is presented and compared with test data. The steady state heat balance for a single wire is derived and extended to the bundle configuration. The generalized model includes the effects of temperature varying resistance, internal radiation and thermal interface conductance, external radiation and temperature varying convective relief from the free surface. The sensitivity of the response to uncertainties in key model parameters is explored using Monte Carlo analysis.
DEFF Research Database (Denmark)
Leeters, Irene P M; Davis, Ashlee; Zusterzeel, Robbert
2016-01-01
and anterior LV walls, similar to abnormalities between septal and lateral walls in LBBB. METHODS AND RESULTS: Ten healthy volunteers with no-BBB, 28 LBBB and 28 RBBB+LAFB heart failure patients were included in this retrospective study. Two-dimensional regional-strains were obtained by speckle-tracking. Scar...
Isothermal microcalorimetry, a tool for probing SWNT bundles.
Marquis, Renaud; Greco, Carla; Schultz, Patrick; Meunier, Stéphane; Mioskowski, Charles
2009-11-01
The bundling state of several dry single-walled carbon nanotube (SWNT) samples is compared using isothermal microcalorimetry (IMC). So as to get different dry samples with various bundling states, the pristine SWNTs were pretreated with a solution of an aromatic amphiphile with or without sonication, washed and dried before being studied by IMC. The bundling state of the different SWNT samples, which was first analyzed by TEM, was then correlated to the obtained IMC data thanks to the interpretation of the observed energy transfer phenomena. From our results, IMC appears to be an interesting technique for the surface probing of dry SWNT samples, and herein for the evaluation of the bundling state.
Restriction Theorem for Principal bundles in Arbitrary Characteristic
DEFF Research Database (Denmark)
Gurjar, Sudarshan
2015-01-01
The aim of this paper is to prove two basic restriction theorem for principal bundles on smooth projective varieties in arbitrary characteristic generalizing the analogues theorems of Mehta-Ramanathan for vector bundles. More precisely, let G be a reductive algebraic group over an algebraically...... closed field k and let X be a smooth, projective variety over k together with a very ample line bundle O(1). The main result of the paper is that if E is a semistable (resp. stable) principal G-bundle on X w.r.t O(1), then the restriction of E to a general, high multi-degree, complete-intersection curve...
Enthalpy and void distributions in subchannels of PHWR fuel bundles
Energy Technology Data Exchange (ETDEWEB)
Park, J. W.; Choi, H.; Rhee, B. W. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)
1998-12-31
Two different types of the CANDU fuel bundles have been modeled for the ASSERT-IV code subchannel analysis. From calculated values of mixture enthalpy and void fraction distribution in the fuel bundles, it is found that net buoyancy effect is pronounced in the central region of the DUPIC fuel bundle when compared with the standard CANDU fuel bundle. It is also found that the central region of the DUPIC fuel bundle can be cooled more efficiently than that of the standard fuel bundle. From the calculated mixture enthalpy distribution at the exit of the fuel channel, it is found that the mixture enthalpy and void fraction can be highest in the peripheral region of the DUPIC fuel bundle. On the other hand, the enthalpy and the void fraction were found to be highest in the central region of the standard CANDU fuel bundle at the exit of the fuel channel. This study shows that the subchannel analysis is very useful in assessing thermal behavior of the fuel bundle that could be used in CANDU reactors. 10 refs., 4 figs., 2 tabs. (Author)
Bundled capillary electrophoresis using microstructured fibres.
Rogers, Benjamin; Gibson, Graham T T; Oleschuk, Richard D
2011-01-01
Joule heating, arising from the electric current passing through the capillary, causes many undesired effects in CE that ultimately result in band broadening. The use of narrow-bore capillaries helps to solve this problem as smaller cross-sectional area results in decreased Joule heating and the rate of heat dissipation is increased by the larger surface-to-volume ratio. Issues arising from such small capillaries, such as poor detection sensitivity, low loading capacity and high flow-induced backpressure (complicating capillary loading) can be avoided by using a bundle of small capillaries operating simultaneously that share buffer reservoirs. Microstructured fibres, originally designed as waveguides in the telecommunication industry, are essentially a bundle of parallel ∼5 μm id channels that extend the length of a fibre having otherwise similar dimensions to conventional CE capillaries. This work presents the use of microstructured fibres for CZE, taking advantage of their relatively high surface-to-volume ratio and the small individual size of each channel to effect highly efficient separations, particularly for dye-labelled peptides.
Development boiling to sprinkled tube bundle
Directory of Open Access Journals (Sweden)
Kracík Petr
2016-01-01
Full Text Available This paper presents results of a studied heat transfer coefficient at the surface of a sprinkled tube bundle where boiling occurs. Research in the area of sprinkled exchangers can be divided into two major parts. The first part is research on heat transfer and determination of the heat transfer coefficient at sprinkled tube bundles for various liquids, whether boiling or not. The second part is testing of sprinkle modes for various tube diameters, tube pitches and tube materials and determination of individual modes’ interface. All results published so far for water as the falling film liquid apply to one to three tubes for which the mentioned relations studied are determined in rigid laboratory conditions defined strictly in advance. The sprinkled tubes were not viewed from the operational perspective where there are more tubes and various modes may occur in different parts with various heat transfer values. The article focuses on these processes. The tube is located in a low-pressure chamber where vacuum is generated using an exhauster via ejector. The tube consists of smooth copper tubes of 12 mm diameter placed horizontally one above another.
Development boiling to sprinkled tube bundle
Kracík, Petr; Pospíšil, Jiří
2016-03-01
This paper presents results of a studied heat transfer coefficient at the surface of a sprinkled tube bundle where boiling occurs. Research in the area of sprinkled exchangers can be divided into two major parts. The first part is research on heat transfer and determination of the heat transfer coefficient at sprinkled tube bundles for various liquids, whether boiling or not. The second part is testing of sprinkle modes for various tube diameters, tube pitches and tube materials and determination of individual modes' interface. All results published so far for water as the falling film liquid apply to one to three tubes for which the mentioned relations studied are determined in rigid laboratory conditions defined strictly in advance. The sprinkled tubes were not viewed from the operational perspective where there are more tubes and various modes may occur in different parts with various heat transfer values. The article focuses on these processes. The tube is located in a low-pressure chamber where vacuum is generated using an exhauster via ejector. The tube consists of smooth copper tubes of 12 mm diameter placed horizontally one above another.
Energy Technology Data Exchange (ETDEWEB)
Nichita, E., E-mail: Eleodor.Nichita@uoit.ca; Haroon, J., E-mail: Jawad.Haroon@uoit.ca
2016-10-15
Highlights: • A 37-element fuel bundle modified for {sup 99}Mo production in CANDU reactors is presented. • The modified bundle is neutronically and thermal-hydraulically equivalent to the standard bundle. • The modified bundle satisfies all safety criteria satisfied by the standard bundle. - Abstract: {sup 99m}Tc, the most commonly used radioisotope in diagnostic nuclear medicine, results from the radioactive decay of {sup 99}Mo which is currently being produced at various research reactors around the globe. In this study, the potential use of CANDU power reactors for the production of {sup 99}Mo is investigated. A modified 37-element fuel bundle, suitable for the production of {sup 99}Mo in existing CANDU-type reactors is proposed. The new bundle is specifically designed to be neutronically and thermal-hydraulically equivalent to the standard 37-element CANDU fuel bundle in normal, steady-state operation and, at the same time, be able to produce significant quantities of {sup 99}Mo when irradiated in a CANDU reactor. The proposed bundle design uses fuel pins consisting of a depleted-uranium centre surrounded by a thin layer of low-enriched uranium. The new molybdenum-producing bundle is analyzed using the lattice transport code DRAGON and the diffusion code DONJON. The proposed design is shown to produce 4081 six-day Curies of {sup 99}Mo activity per bundle when irradiated in the peak-power channel of a CANDU core, while maintaining the necessary reactivity and power rating limits. The calculated {sup 99}Mo yield corresponds to approximately one third of the world weekly demand. A production rate of ∼3 bundles per week can meet the global demand of {sup 99}Mo.
Coupled mode analysis of a periodic one-dimensional multimodal fiber bundle
Shlivinski, Amir
2016-10-01
This contribution is a mathematical analysis of the coupled mode equations of a one dimensional infinite periodic lattice of multimodal adjacent fibers that are fused together (a "fiber bundle"). As such, it provides a systematic and detailed derivation of the coupled mode equations and their eigen (modal) solutions within a matrix-based framework and using Z -transform spectral-based formulation. The resulting solution is general in the sense that it is not restricted to a particular dielectric profile of the fibers. Moreover, under a weak coupling assumption, the modal solution clearly identifies the physical building blocks of the solution.
Directory of Open Access Journals (Sweden)
Masataka Deie
2015-01-01
Full Text Available Background. Posterior cruciate ligament (PCL injuries are not rare in acute knee injuries, and several recent anatomical studies of the PCL and reconstructive surgical techniques have generated improved patient results. Now, we have evaluated PCL reconstructions performed by either the single-bundle or double-bundle technique in a patient group followed up retrospectively for more than 10 years. Methods. PCL reconstructions were conducted using the single-bundle (27 cases or double-bundle (13 cases method from 1999 to 2002. The mean age at surgery was 34 years in the single-bundle group and 32 years in the double-bundle group. The mean follow-up period was 12.5 years. Patients were evaluated by Lysholm scoring, the gravity sag view, and knee arthrometry. Results. The Lysholm score after surgery was 89.1±5.6 points for the single-bundle group and 91.9±4.5 points for the double-bundle group. There was no significant difference between the methods in the side-to-side differences by gravity sag view or knee arthrometer evaluation, although several cases in both groups showed a side-to-side difference exceeding 5 mm by the latter evaluation method. Conclusions. We found no significant difference between single- and double-bundle PCL reconstructions during more than 10 years of follow-up.
Safety assessment for the CANFLEX-NU fuel bundles with respect to the 37-element fuel bundles
Energy Technology Data Exchange (ETDEWEB)
Suk, H. C.; Lim, H. S. [Korea Atomic Energy Research Institute, Taejon (Korea)
1999-11-01
The KAERI and AECL have jointly developed an advanced CANDU fuel, called CANFLEX-NU fuel bundle. CANFLEX 43-element bundle has some improved features of increased operating margin and enhanced safety compared to the existing 37-element bundle. Since CANFLEX fuel bundle is designed to be compatible with the CANDU-6 reactor design, the behaviour in the thermalhydraulic system will be nearly identical with 37-element bundle. But due to different element design and linear element power distribution between the two bundles, it is expected that CANFLEX fuel behaviour would be different from the behaviour of the 37-element fuel. Therefore, safety assessments on the design basis accidents which result if fuel failures are performed. For all accidents selected, it is observed that the loading of CANFLEX bundle in an existing CANDU-6 reactor would not worsen the reactor safety. It is also predicted that fission product release for CANFLEX fuel bundle generally is lower than that for 37-element bundle. 3 refs., 2 figs., 2 tabs. (Author)
Coherent hollow-core waveguide bundles for thermal imaging.
Gal, Udi; Harrington, James; Ben-David, Moshe; Bledt, Carlos; Syzonenko, Nicholas; Gannot, Israel
2010-09-01
There has been very little work done in the past to extend the wavelength range of fiber image bundles to the IR range. This is due, in part, to the lack of IR transmissive fibers with optical and mechanical properties analogous to the oxide glass fibers currently employed in the visible fiber bundles. Our research is aimed at developing high-resolution hollow-core coherent IR fiber bundles for transendoscopic infrared imaging. We employ the hollow glass waveguide (HGW) technology that was used successfully to make single-HGWs with Ag/AgI thin film coatings to form coherent bundles for IR imaging. We examine the possibility of developing endoscopic systems to capture thermal images using hollow waveguide fiber bundles adjusted to the 8-10?mum spectral range and investigate the applicability of such systems. We carried out a series of measurements in order to characterize the optical properties of the fiber bundles. These included the attenuation, resolution, and temperature response. We developed theoretical models and simulation tools that calculate the light propagation through HGW bundles, and which can be used to calculate the optical properties of the fiber bundles. Finally, the HGW fiber bundles were used to transmit thermal images of various heated objects; the results were compared with simulation results. The experimental results are encouraging, show an improvement in the resolution and thermal response of the HGW fiber bundles, and are consistent with the theoretical results. Nonetheless, additional improvements in the attenuation of the bundles are required in order to be able to use this technology for medical applications.
Non-abelian higher gauge theory and categorical bundle
Viennot, David
2012-01-01
A gauge theory is associated with a principal bundle endowed with a connection permitting to define horizontal lifts of paths. The horizontal lifts of surfaces cannot be defined into a principal bundle structure. An higher gauge theory is an attempt to generalize the bundle structure in order to describe horizontal lifts of surfaces. A such attempt is particularly difficult for the non-abelian case. Some structures have been proposed to realize this goal (twisted bundle, gerbes with connection, bundle gerbe, 2-bundle). Each of them uses a category in place of the total space manifold of the usual principal bundle structure. Some of them replace also the structure group by a category (more precisely a Lie crossed module viewed as a category). But the base space remains still a simple manifold (possibly viewed as a trivial category with only identity arrows). We propose a new principal categorical bundle structure, with a Lie crossed module as structure groupoid, but with a base space belonging to a bigger clas...
Smooth Bundling of Large Streaming and Sequence Graphs
Hurter, C.; Ersoy, O.; Telea, A.
2013-01-01
Dynamic graphs are increasingly pervasive in modern information systems. However, understanding how a graph changes in time is difficult. We present here two techniques for simplified visualization of dynamic graphs using edge bundles. The first technique uses a recent image-based graph bundling met
Helical twist controls the thickness of F-actin bundles
Claessens, M.M.A.E.; Semmrich, C.; Ramos, L.; Bausch, A.R.
2008-01-01
In the presence of condensing agents such as nonadsorbing polymer, multivalent counter ions, and specific bundling proteins, chiral biopolymers typically form bundles with a finite thickness, rather than phase-separating into a polymer-rich phase. Although short-range repulsive interactions or geome
Lexical Bundles in L1 and L2 Academic Writing
Chen, Yu-Hua; Baker, Paul
2010-01-01
This paper adopts an automated frequency-driven approach to identify frequently-used word combinations (i.e., "lexical bundles") in academic writing. Lexical bundles retrieved from one corpus of published academic texts and two corpora of student academic writing (one L1, the other L2), were investigated both quantitatively and qualitatively.…
Lexical Bundles: Facilitating University "Talk" in Group Discussions
Heng, Chan Swee; Kashiha, Hadi; Tan, Helen
2014-01-01
Group discussion forms an integral language experience for most language learners, providing them with an opportunity to express themselves in a naturalistic setting. Multi-word expressions are commonly used and one of them is lexical bundles. Lexical bundles are types of extended collocations that occur more commonly than we expect; they are…
Vector bundles of rank 2 computing Clifford indices
Lange, H
2010-01-01
Clifford indices of vector bundles on algebraic curves were introduced in a previous paper of the authors. In this paper we study bundles of rank 2 which compute these Clifford indices. This is of particular interest in the light of recently discovered counterexamples to a conjecture of Mercat.
On the general elephant conjecture for Mori conic bundles
Prokhorov, Yu G
1996-01-01
Let $f:X\\to S$ be an extremal contraction from a threefolds with terminal singularities onto a surface (so called Mori conic bundle). We study some particular cases of such contractions: quotients of usual conic bundles and index two contractions. Assuming Reid's general elephants conjecture we also obtain a rough classification. We present many examples.
Subanalytic Bundles and Tubular Neighbourhoods of Zero-Loci
Indian Academy of Sciences (India)
Vishwambhar Pati
2003-08-01
We introduce the natural and fairly general notion of a subanalytic bundle (with a finite dimensional vector space of sections) on a subanalytic subset of a real analytic manifold , and prove that when is compact, there is a Baire subset of sections in whose zero-loci in have tubular neighbourhoods, homeomorphic to the restriction of the given bundle to these zero-loci.
Computational imaging through a fiber-optic bundle
Lodhi, Muhammad A.; Dumas, John Paul; Pierce, Mark C.; Bajwa, Waheed U.
2017-05-01
Compressive sensing (CS) has proven to be a viable method for reconstructing high-resolution signals using low-resolution measurements. Integrating CS principles into an optical system allows for higher-resolution imaging using lower-resolution sensor arrays. In contrast to prior works on CS-based imaging, our focus in this paper is on imaging through fiber-optic bundles, in which manufacturing constraints limit individual fiber spacing to around 2 μm. This limitation essentially renders fiber-optic bundles as low-resolution sensors with relatively few resolvable points per unit area. These fiber bundles are often used in minimally invasive medical instruments for viewing tissue at macro and microscopic levels. While the compact nature and flexibility of fiber bundles allow for excellent tissue access in-vivo, imaging through fiber bundles does not provide the fine details of tissue features that is demanded in some medical situations. Our hypothesis is that adapting existing CS principles to fiber bundle-based optical systems will overcome the resolution limitation inherent in fiber-bundle imaging. In a previous paper we examined the practical challenges involved in implementing a highly parallel version of the single-pixel camera while focusing on synthetic objects. This paper extends the same architecture for fiber-bundle imaging under incoherent illumination and addresses some practical issues associated with imaging physical objects. Additionally, we model the optical non-idealities in the system to get lower modelling errors.
Parabolic stable Higgs bundles over complete noncompact Riemann surfaces
Institute of Scientific and Technical Information of China (English)
李嘉禹; 王友德
1999-01-01
Let M be an open Riemann surface with a finite set of punctures, a complete Poincar(?)-like metric is introduced near the punctures and the equivalence between the stability of an indecomposable parabolic Higgs bundle, and the existence of a Hermitian-Einstein metric on the bundle is established.
Lexical Bundles in L1 and L2 Academic Writing
Chen, Yu-Hua; Baker, Paul
2010-01-01
This paper adopts an automated frequency-driven approach to identify frequently-used word combinations (i.e., "lexical bundles") in academic writing. Lexical bundles retrieved from one corpus of published academic texts and two corpora of student academic writing (one L1, the other L2), were investigated both quantitatively and qualitatively.…
An integral Riemann-Roch theorem for surface bundles
DEFF Research Database (Denmark)
Madsen, Ib Henning
2010-01-01
This paper is a response to a conjecture by T. Akita about an integral Riemann–Roch theorem for surface bundles.......This paper is a response to a conjecture by T. Akita about an integral Riemann–Roch theorem for surface bundles....
On the Classification of Complex Vector Bundles of Stable Rank
Indian Academy of Sciences (India)
Constantin Bǎnicǎ; Mihai Putinar
2006-08-01
One describes, using a detailed analysis of Atiyah–Hirzebruch spectral sequence, the tuples of cohomology classes on a compact, complex manifold, corresponding to the Chern classes of a complex vector bundle of stable rank. This classification becomes more effective on generalized flag manifolds, where the Lie algebra formalism and concrete integrability conditions describe in constructive terms the Chern classes of a vector bundle.
Bundled automobile insurance coverage and accidents.
Li, Chu-Shiu; Liu, Chwen-Chi; Peng, Sheng-Chang
2013-01-01
This paper investigates the characteristics of automobile accidents by taking into account two types of automobile insurance coverage: comprehensive vehicle physical damage insurance and voluntary third-party liability insurance. By using a unique data set in the Taiwanese automobile insurance market, we explore the bundled automobile insurance coverage and the occurrence of claims. It is shown that vehicle physical damage insurance is the major automobile coverage and affects the decision to purchase voluntary liability insurance coverage as a complement. Moreover, policyholders with high vehicle physical damage insurance coverage have a significantly higher probability of filing vehicle damage claims, and if they additionally purchase low voluntary liability insurance coverage, their accident claims probability is higher than those who purchase high voluntary liability insurance coverage. Our empirical results reveal that additional automobile insurance coverage information can capture more driver characteristics and driving behaviors to provide useful information for insurers' underwriting policies and to help analyze the occurrence of automobile accidents.
Habibi, Somayeh
2011-01-01
Let $G$ be a reductive algebraic group over a perfect field $k$ and $\\mathcal{G}$ a $G$-bundle over a scheme $X/k$. The main aim of this article is to study the motive associated with $\\mathcal{G}$, inside the Veovodsky Motivic categories. We consider the case that $\\charakt k=0$ (resp. $\\charakt k\\geq 0$), the motive associated to $X$ is geometrically mixed Tate (resp. geometrically cellular) and $\\mathcal{G}$ is locally trivial for the Zariski (resp. \\'etale) topology on $X$ and show that the motive of $\\mathcal{G}$ is a geometrically mixed Tate motive. Moreover for a general $X$ we construct a filtration on the motive associated to $\\mathcal{G}$ in terms of weight polytopes. Along the way we give some applications and examples.
Fiber bundle model under fluid pressure
Amitrano, David; Girard, Lucas
2016-03-01
Internal fluid pressure often plays an important role in the rupture of brittle materials. This is a major concern for many engineering applications and for natural hazards. More specifically, the mechanisms through which fluid pressure, applied at a microscale, can enhance the failure at a macroscale and accelerate damage dynamics leading to failure remains unclear. Here we revisit the fiber bundle model by accounting for the effect of fluid under pressure that contributes to the global load supported by the fiber bundle. Fluid pressure is applied on the broken fibers, following Biot's theory. The statistical properties of damage avalanches and their evolution toward macrofailure are analyzed for a wide range of fluid pressures. The macroscopic strength of the new model appears to be strongly controlled by the action of the fluid, particularly when the fluid pressure becomes comparable with the fiber strength. The behavior remains consistent with continuous transition, i.e., second order, including for large pressure. The main change concerns the damage acceleration toward the failure that is well modeled by the concept of sweeping of an instability. When pressure is increased, the exponent β characterizing the power-law distribution avalanche sizes significantly decreases and the exponent γ characterizing the cutoff divergence when failure is approached significantly increases. This proves that fluid pressure plays a key role in failure process acting as destabilization factor. This indicates that macrofailure occurs more readily under fluid pressure, with a behavior that becomes progressively unstable as fluid pressure increases. This may have considerable consequences on our ability to forecast failure when fluid pressure is acting.
Artificial ciliary bundles with nano fiber tip links
Asadnia, Mohsen; Miao, Jianmin; Triantafyllou, Michael
2015-01-01
Mechanosensory ciliary bundles in fishes are the inspiration for carefully engineered artificial flow sensors. We report the development of a new class of ultrasensitive MEMS flow sensors that mimic the intricate morphology of the ciliary bundles, including the stereocilia, tip links, and the cupula, and thereby achieve threshold detection limits that match the biological example. An artificial ciliary bundle is achieved by fabricating closely-spaced arrays of polymer micro-pillars with gradiating heights. Tip links that form the fundamental sensing elements are realized through electrospinning aligned PVDF piezoelectric nano-fibers that link the distal tips of the polymer cilia. An optimized synthesis of hyaluronic acid-methacrylic anhydride hydrogel that results in properties close to the biological cupula, together with drop-casting method are used to form the artificial cupula that encapsulates the ciliary bundle. In testing, fluid drag force causes the ciliary bundle to slide, stretching the flexible nan...
HORIZONTAL LAPLACE OPERATOR IN REAL FINSLER VECTOR BUNDLES
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
A vector bundle F over the tangent bundle TM of a manifold M is said to be a Finsler vector bundle if it is isomorphic to the pull-back π*E of a vector bundle E over M([1]). In this article the authors study the h-Laplace operator in Finsler vector bundles.An h-Laplace operator is defined, first for functions and then for horizontal Finsler forms on E. Using the h-Laplace operator, the authors define the h-harmonic function and h-harmonic horizontal Finsler vector fields, and furthermore prove some integral formulas for the h-Laplace operator, horizontal Finsler vector fields, and scalar fields on E.
The 2-Hilbert Space of a Prequantum Bundle Gerbe
Bunk, Severin; Szabo, Richard J
2016-01-01
We construct a prequantum 2-Hilbert space for any line bundle gerbe whose Dixmier-Douady class is torsion. Analogously to usual prequantisation, this 2-Hilbert space has the category of sections of the line bundle gerbe as its underlying 2-vector space. These sections are obtained as certain morphism categories in Waldorf's version of the 2-category of line bundle gerbes. We show that these morphism categories carry a monoidal structure under which they are semisimple and abelian. We introduce a dual functor on the sections, which yields a closed structure on the morphisms between bundle gerbes and turns the category of sections into a 2-Hilbert space. We discuss how these 2-Hilbert spaces fit various expectations from higher prequantisation. We then extend the transgression functor to the full 2-category of bundle gerbes and demonstrate its compatibility with the additional structures introduced. We discuss various aspects of Kostant-Souriau prequantisation in this setting, including its dimensional reductio...
Bundles over Quantum RealWeighted Projective Spaces
Directory of Open Access Journals (Sweden)
Tomasz Brzeziński
2012-09-01
Full Text Available The algebraic approach to bundles in non-commutative geometry and the definition of quantum real weighted projective spaces are reviewed. Principal U(1-bundles over quantum real weighted projective spaces are constructed. As the spaces in question fall into two separate classes, the negative or odd class that generalises quantum real projective planes and the positive or even class that generalises the quantum disc, so do the constructed principal bundles. In the negative case the principal bundle is proven to be non-trivial and associated projective modules are described. In the positive case the principal bundles turn out to be trivial, and so all the associated modules are free. It is also shown that the circle (coactions on the quantum Seifert manifold that define quantum real weighted projective spaces are almost free.
A geometric approach to noncommutative principal torus bundles
DEFF Research Database (Denmark)
Wagner, Stefan
2013-01-01
for noncommutative algebras and say that a dynamical system (A, 핋n,α) is called a noncommutative principal 핋n-bundle, if localization leads to a trivial noncommutative principal 핋n-bundle. We prove that this approach extends the classical theory of principal torus bundles and present a bunch of (nontrivial......A (smooth) dynamical system with transformation group 핋n is a triple (A, 핋n,α), consisting of a unital locally convex algebra A, the n-torus 핋n and a group homomorphism α:핋n→Aut(A), which induces a (smooth) continuous action of 핋n on A. In this paper, we present a new, geometrically oriented...... approach to the noncommutative geometry of principal torus bundles based on such dynamical systems. Our approach is inspired by the classical setting: In fact, after recalling the definition of a trivial noncommutative principal torus bundle, we introduce a convenient (smooth) localization method...
Morse theory for the space of Higgs G-bundles
Biswas, Indranil
2010-01-01
Fix a $C^\\infty$ principal $G$--bundle $E^0_G$ on a compact connected Riemann surface $X$, where $G$ is a connected complex reductive linear algebraic group. We consider the gradient flow of the Yang--Mills--Higgs functional on the cotangent bundle of the space of all smooth connections on $E^0_G$. We prove that this flow preserves the subset of Higgs $G$--bundles, and, furthermore, the flow emanating from any point of this subset has a limit. Given a Higgs $G$--bundle, we identify the limit point of the integral curve passing through it. These generalize the results of the second named author on Higgs vector bundles.
Voltage- and calcium-dependent motility of saccular hair bundles
Quiñones, Patricia M.; Meenderink, Sebastiaan W. F.; Bozovic, Dolores
2015-12-01
Active bundle motility, which is hypothesized to supply feedback for mechanical amplification of signals, is thought to enhance sensitivity and sharpen tuning in vestibular and auditory organs. To study active hair bundle motility, we combined high-speed camera recordings of bullfrog sacculi, which were mounted in a two-compartment chamber, and voltage-clamp of the hair cell membrane potential. Using this paradigm, we measured three types of bundle motions: 1) spontaneous oscillations which can be analyzed to measure the physiological operating range of the transduction channel; 2) a sustained quasi-static movement of the bundle that depends on membrane potential; and 3) a fast, transient and asymmetric movement that resets the bundle position and depends on changes in the membrane potential. These data support a role for both calcium and voltage in the transduction-channel function.
Superconductivity in an Inhomogeneous Bundle of Metallic and Semiconducting Nanotubes
Directory of Open Access Journals (Sweden)
Ilya Grigorenko
2013-01-01
Full Text Available Using Bogoliubov-de Gennes formalism for inhomogeneous systems, we have studied superconducting properties of a bundle of packed carbon nanotubes, making a triangular lattice in the bundle's transverse cross-section. The bundle consists of a mixture of metallic and doped semiconducting nanotubes, which have different critical transition temperatures. We investigate how a spatially averaged superconducting order parameter and the critical transition temperature depend on the fraction of the doped semiconducting carbon nanotubes in the bundle. Our simulations suggest that the superconductivity in the bundle will be suppressed when the fraction of the doped semiconducting carbon nanotubes will be less than 0.5, which is the percolation threshold for a two-dimensional triangular lattice.
Energy Technology Data Exchange (ETDEWEB)
Bes, T. [Szczecin Univ. of Technology (Poland). Dept. of Heat Engineering
2006-07-01
The system consisting of a biomass-furnace and a Stirling engine as an electricity generator is analysed from thermal point of view. The analysis is focused on a selected element of such a system i.e. a block with a bundle of tubes located in the furnace in the way of combustion gases. The working fluid circulates between the cylinders of the Stirling engine and inside the tube bundle, in which the gas flow is arranged as a co-directed cross-flow. For any given number of tubes in the bundle other ways of switching between tubes are also analysed. The tube bundles have also been examined for various proportions of mass flows in the apparatus. Moreover a whole spectrum of NTU is taken into account. Due to low combustion heat of biomass the temperature of combustion gas is relatively low (below {proportional_to}800oC). This is not sufficient to achieve adequate thermal efficiency, which is significantly below the efficiency of a conventional power plant. Therefore by improving the conditions for heat transfer within the tube bundle it is possible to increase the gas temperature as much as possible and also efficiency of the system. Thus, proper operation of the bundle is the critical element for the examined device. (orig.)
CHF Enhancement of Advanced 37-Element Fuel Bundles
Directory of Open Access Journals (Sweden)
Joo Hwan Park
2015-01-01
Full Text Available A standard 37-element fuel bundle (37S fuel bundle has been used in commercial CANDU reactors for over 40 years as a reference fuel bundle. Most CHF of a 37S fuel bundle have occurred at the elements arranged in the inner pitch circle for high flows and at the elements arranged in the outer pitch circle for low flows. It should be noted that a 37S fuel bundle has a relatively small flow area and high flow resistance at the peripheral subchannels of its center element compared to the other subchannels. The configuration of a fuel bundle is one of the important factors affecting the local CHF occurrence. Considering the CHF characteristics of a 37S fuel bundle in terms of CHF enhancement, there can be two approaches to enlarge the flow areas of the peripheral subchannels of a center element in order to enhance CHF of a 37S fuel bundle. To increase the center subchannel areas, one approach is the reduction of the diameter of a center element, and the other is an increase of the inner pitch circle. The former can increase the total flow area of a fuel bundle and redistributes the power density of all fuel elements as well as the CHF. On the other hand, the latter can reduce the gap between the elements located in the middle and inner pitch circles owing to the increasing inner pitch circle. This can also affect the enthalpy redistribution of the fuel bundle and finally enhance CHF or dry-out power. In this study, the above two approaches, which are proposed to enlarge the flow areas of the center subchannels, were considered to investigate the impact of the flow area changes of the center subchannels on the CHF enhancement as well as the thermal characteristics by applying a subchannel analysis method.
Schalk, S.
1999-01-01
In contrast to the neo-classical theory of Arrow and Debreu, a model of a private ownership economy is presented, in which production and consumption bundles are treated separately. Each of the two types of bundles is assumed to establish a con- vex cone. Production technologies can convert producti
Schalk, S.
1999-01-01
In contrast to the neo-classical theory of Arrow and Debreu, a model of a private ownership economy is presented, in which production and consumption bundles are treated separately. Each of the two types of bundles is assumed to establish a con- vex cone. Production technologies can convert
Differential geometry and mathematical physics part II fibre bundles, topology and gauge fields
Rudolph, Gerd
2017-01-01
The book is devoted to the study of the geometrical and topological structure of gauge theories. It consists of the following three building blocks:- Geometry and topology of fibre bundles,- Clifford algebras, spin structures and Dirac operators,- Gauge theory.Written in the style of a mathematical textbook, it combines a comprehensive presentation of the mathematical foundations with a discussion of a variety of advanced topics in gauge theory.The first building block includes a number of specific topics, like invariant connections, universal connections, H-structures and the Postnikov approximation of classifying spaces.Given the great importance of Dirac operators in gauge theory, a complete proof of the Atiyah-Singer Index Theorem is presented. The gauge theory part contains the study of Yang-Mills equations (including the theory of instantons and the classical stability analysis), the discussion of various models with matter fields (including magnetic monopoles, the Seiberg-Witten model and dimensional r...
Bundling Actin Filaments From Membranes: Some Novel Players
Directory of Open Access Journals (Sweden)
Clément eThomas
2012-08-01
Full Text Available Progress in live-cell imaging of the cytoskeleton has significantly extended our knowledge about the organization and dynamics of actin filaments near the plasma membrane of plant cells. Noticeably, two populations of filamentous structures can be distinguished. On the one hand, fine actin filaments which exhibit an extremely dynamic behavior basically characterized by fast polymerization and prolific severing events, a process referred to as actin stochastic dynamics. On the other hand, thick actin bundles which are composed of several filaments and which are comparatively more stable although they constantly remodel as well. There is evidence that the actin cytoskeleton plays critical roles in trafficking and signaling at both the cell cortex and organelle periphery but the exact contribution of actin bundles remains unclear. A common view is that actin bundles provide the long-distance tracks used by myosin motors to deliver their cargo to growing regions and accordingly play a particularly important role in cell polarization. However, several studies support that actin bundles are more than simple passive highways and display multiple and dynamic roles in the regulation of many processes, such as cell elongation, polar auxin transport, stomatal and chloroplast movement, and defense against pathogens. The list of identified plant actin-bundling proteins is ever expanding, supporting that plant cells shape structurally and functionally different actin bundles. Here I review the most recently characterized actin-bundling proteins, with a particular focus on those potentially relevant to membrane trafficking and/or signaling.
Bondage Numbers of C4 Bundles over a Cycle Cn
Directory of Open Access Journals (Sweden)
Moo Young Sohn
2013-01-01
Full Text Available Graph bundles generalize the notion of covering graphs and graph products. Graph bundles have been applied in computer architecture and communication networks. The bondage number is an important parameter for measuring the vulnerability and stability of the network domination under link failure. The bondage number b(G of a graph G is the minimum number of edges whose removal enlarges the domination number. In this paper, we show that the bondage number of every C4 bundles over a cycle Cn (n≥4 is equal to 4.
The Born rule as structure of spectral bundles (extended abstract
Directory of Open Access Journals (Sweden)
Bertfried Fauser
2012-10-01
Full Text Available Topos approaches to quantum foundations are described in a unified way by means of spectral bundles, where the base space is a space of contexts and each fibre is its spectrum. Differences in variance are due to the bundle being a fibration or opfibration. Relative to this structure, the probabilistic predictions of the Born rule in finite dimensional settings are then described as a section of a bundle of valuations. The construction uses in an essential way the geometric nature of the valuation locale monad.
—Impact of Customer Knowledge Heterogeneity on Bundling Strategy
Amiya Basu; Padmal Vitharana
2009-01-01
We consider a marketer of components who can select one of three alternative pricing strategies: (1) a pure component strategy (i.e., the customer can only buy the components individually), (2) a pure bundling strategy (i.e., the components must be purchased together), or (3) a mixed bundling strategy (i.e., the customer may buy a component individually, or buy the bundle). We consider a market where customer knowledge of components varies and propose that a high-knowledge customer can determ...
Systematic evaluation of bundled SPC water for biomolecular simulations.
Gopal, Srinivasa M; Kuhn, Alexander B; Schäfer, Lars V
2015-04-07
In bundled SPC water models, the relative motion of groups of four water molecules is restrained by distance-dependent potentials. Bundled SPC models have been used in hybrid all-atom/coarse-grained (AA/CG) multiscale simulations, since they enable to couple atomistic SPC water with supra-molecular CG water models that effectively represent more than a single water molecule. In the present work, we systematically validated and critically tested bundled SPC water models as solvent for biomolecular simulations. To that aim, we investigated both thermodynamic and structural properties of various biomolecular systems through molecular dynamics (MD) simulations. Potentials of mean force of dimerization of pairs of amino acid side chains as well as hydration free energies of single side chains obtained with bundled SPC and standard (unrestrained) SPC water agree closely with each other and with experimental data. Decomposition of the hydration free energies into enthalpic and entropic contributions reveals that in bundled SPC, this favorable agreement of the free energies is due to a larger degree of error compensation between hydration enthalpy and entropy. The Ramachandran maps of Ala3, Ala5, and Ala7 peptides are similar in bundled and unrestrained SPC, whereas for the (GS)2 peptide, bundled water leads to a slight overpopulation of extended conformations. Analysis of the end-to-end distance autocorrelation times of the Ala5 and (GS)2 peptides shows that sampling in more viscous bundled SPC water is about two times slower. Pronounced differences between the water models were found for the structure of a coiled-coil dimer, which is instable in bundled SPC but not in standard SPC. In addition, the hydration of the active site of the serine protease α-chymotrypsin depends on the water model. Bundled SPC leads to an increased hydration of the active site region, more hydrogen bonds between water and catalytic triad residues, and a significantly slower exchange of water
Shatz, L F
2000-03-01
The relationship between size and shape of the hair bundle of a hair cell in the inner ear and its sensitivity at asymptotically high and low frequencies was determined, thereby extending the results of an analysis of hair bundle hydrodynamics in two dimensions (Freeman and Weiss, 1990. Hydrodynamic analysis of a two-dimensional model for micromechanical resonance of free-standing hair bundles. Hear. Res. 48, 37-68) to three dimensions. A hemispheroid was used to represent the hair bundle. The hemispheroid had a number of advantages: it could represent shapes that range from thin, pencil-like shapes, to wide, flat, disk-like shapes. Also analytic methods could be used in the high frequency range to obtain an exact solution to the equations of motion. In the low frequency range, where an approximate solution was found using boundary element methods, the sensitivity of the responses of hair cells was mainly proportional to the cube of the heights of their hair bundles, and at high frequencies, the sensitivity of the hair cells was mainly proportional to the inverse of their heights. An excellent match was obtained between measurements of sensitivity curves in the basillar papilla of the alligator and bobtail lizards and the model's predictions. These results also suggest why hair bundles of hair cells in vestibular organs which are sensitive to low frequencies have ranges of heights that are an order of magnitude larger than the range of heights of hair bundles of hair cells found in auditory organs.
A study of bacterial flagellar bundling.
Flores, Heather; Lobaton, Edgar; Méndez-Diez, Stefan; Tlupova, Svetlana; Cortez, Ricardo
2005-01-01
Certain bacteria, such as Escherichia coli (E. coli) and Salmonella typhimurium (S. typhimurium), use multiple flagella often concentrated at one end of their bodies to induce locomotion. Each flagellum is formed in a left-handed helix and has a motor at the base that rotates the flagellum in a corkscrew motion. We present a computational model of the flagellar motion and their hydrodynamic interaction. The model is based on the equations of Stokes flow to describe the fluid motion. The elasticity of the flagella is modeled with a network of elastic springs while the motor is represented by a torque at the base of each flagellum. The fluid velocity due to the forces is described by regularized Stokeslets and the velocity due to the torques by the associated regularized rotlets. Their expressions are derived. The model is used to analyze the swimming motion of a single flagellum and of a group of three flagella in close proximity to one another. When all flagellar motors rotate counterclockwise, the hydrodynamic interaction can lead to bundling. We present an analysis of the flow surrounding the flagella. When at least one of the motors changes its direction of rotation, the same initial conditions lead to a tumbling behavior characterized by the separation of the flagella, changes in their orientation, and no net swimming motion. The analysis of the flow provides some intuition for these processes.
Nursing Care Management: Influence on Bundled Payments.
Lentz, Shaynie; Luther, Brenda
Fragmented and uncoordinated care is the third highest driver of U.S. healthcare costs. Although less than 10% of patients experience uncoordinated care, these patients represent 36% of total healthcare costs; care management interaction makes a significant impact on the utilization of healthcare dollars. A literature search was conducted to construct a model of care coordination for elective surgical procedures by collecting best practices for acute, transitions, and post-acute care periods. A case study was used to demonstrate the model developed. Care management defines care coordination as a model of care to address improving patient and caregiver engagement, communication across settings of care, and ultimately improved patient outcomes of care. Nurse-led care coordination in the presurgical, inpatient, and post-acute care settings requires systems change and administrative support to effectively meet the goals of the Affordable Care Act of reducing redundancy and costs while improving the patient experience. Nursing is the lynchpin of care management processes in all settings of care; thus, this model of care coordination for elective surgical admissions can provide nursing care management leaders a comprehensive view of coordinating care for these patient across settings of care during the predetermined time period of care. As bundled payment structures increasingly affect hospital systems, nursing leaders need to be ready to create or improve their care management processes; care coordination is one such process requiring immediate attention.
LVRF fuel bundle manufacture for Bruce
Energy Technology Data Exchange (ETDEWEB)
Pant, A. [Zircatec Precision Industries, Port Hope, Ontario (Canada)
2005-12-15
In response to the Power Uprate program at Bruce Power, Zircatec has committed to introduce, by Spring 2006 a new manufacturing line for the production of 43 element Bruce LVRF bundles containing Slightly Enriched Uranium (SEU) with a centre pin of blended dysprosia/urania (BDU). This is a new fuel design and is the first change in fuel design since the introduction of the current 37-element fuel over 20 years ago. Introduction of this new line has involved the introduction of significant changes to an environment that is not used to rapid changes with significant impact. At ZPI we have been able to build on our innovative capabilities in new fuel manufacturing, the strength and experience of our core team, and on our prevailing management philosophy of 'support the doer'. The presentation will discuss some of the novel aspects of this fuel introduction and the mix of innovative and classical project management methods that are being used to ensure that project deliveries are being met. Supporting presentations will highlight some of the issues in more detail. (author)
Zeta Functions for Elliptic Curves I. Counting Bundles
Weng, Lin
2012-01-01
To count bundles on curves, we study zetas of elliptic curves and their zeros. There are two types, i.e., the pure non-abelian zetas defined using moduli spaces of semi-stable bundles, and the group zetas defined for special linear groups. In lower ranks, we show that these two types of zetas coincide and satisfy the Riemann Hypothesis. For general cases, exposed is an intrinsic relation on automorphism groups of semi-stable bundles over elliptic curves, the so-called counting miracle. All this, together with Harder-Narasimhan, Desale-Ramanan and Zagier's result, gives an effective way to count semi-stable bundles on elliptic curves not only in terms of automorphism groups but more essentially in terms of their $h^0$'s. Distributions of zeros of high rank zetas are also discussed.
Bundles of Norms About Teen Sex and Pregnancy.
Mollborn, Stefanie; Sennott, Christie
2015-09-01
Teen pregnancy is a cultural battleground in struggles over morality, education, and family. At its heart are norms about teen sex, contraception, pregnancy, and abortion. Analyzing 57 interviews with college students, we found that "bundles" of related norms shaped the messages teens hear. Teens did not think their communities encouraged teen sex or pregnancy, but normative messages differed greatly, with either moral or practical rationalizations. Teens readily identified multiple norms intended to regulate teen sex, contraception, abortion, childbearing, and the sanctioning of teen parents. Beyond influencing teens' behavior, norms shaped teenagers' public portrayals and post hoc justifications of their behavior. Although norm bundles are complex to measure, participants could summarize them succinctly. These bundles and their conflicting behavioral prescriptions create space for human agency in negotiating normative pressures. The norm bundles concept has implications for teen pregnancy prevention policies and can help revitalize social norms for understanding health behaviors.
Design and synthesis of DNA four-helix bundles
Energy Technology Data Exchange (ETDEWEB)
Rangnekar, Abhijit; Gothelf, Kurt V [Department of Chemistry, Centre for DNA Nanotechnology (CDNA) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C (Denmark); LaBean, Thomas H, E-mail: kvg@chem.au.dk, E-mail: thl@cs.duke.edu [Department of Chemistry, Duke University, Durham, NC 27708 (United States)
2011-06-10
The field of DNA nanotechnology has evolved significantly in the past decade. Researchers have succeeded in synthesizing tile-based structures and using them to form periodic lattices in one, two and three dimensions. Origami-based structures have also been used to create nanoscale structures in two and three dimensions. Design and construction of DNA bundles with fixed circumference has added a new dimension to the field. Here we report the design and synthesis of a DNA four-helix bundle. It was found to be extremely rigid and stable. When several such bundles were assembled using appropriate sticky-ends, they formed micrometre-long filaments. However, when creation of two-dimensional sheet-like arrays of the four-helix bundles was attempted, nanoscale rings were observed instead. The exact reason behind the nanoring formation is yet to be ascertained, but it provides an exciting prospect for making programmable circular nanostructures using DNA.
CANFLEX fuel bundle cross-flow endurance test (test report)
Energy Technology Data Exchange (ETDEWEB)
Hong, Sung Deok; Chung, C. H.; Chang, S. K.; Kim, B. D.
1997-04-01
As part of the normal refuelling sequence of CANDU nuclear reactor, both new and irradiated bundles can be parked in the cross-flow region of the liner tubes. This situation occurs normally for a few minutes. The fuel bundle which is subjected to the cross-flow should be capable of withstanding the consequences of cross flow for normal periods, and maintain its mechanical integrity. The cross-flow endurance test was conducted for CANFLEX bundle, latest developed nuclear fuel, at CANDU-Hot Test Loop. The test was carried out during 4 hours at the inlet cross-flow region. After the test, the bundle successfully met all acceptance criteria after the 4 hours cross-flow test. (author). 2 refs., 3 tabs.
On exact triangles consisting of stable vector bundles on tori
Kobayashi, Kazushi
2016-01-01
In this paper, we consider the exact triangles consisting of stable holomorphic vector bundles on one-dimensional complex tori, and discuss their relations with the corresponding Fukaya category via the homological mirror symmetry.
Steric effects induce geometric remodeling of actin bundles in filopodia
Dobramysl, Ulrich; Erban, Radek
2016-01-01
Filopodia are ubiquitous fingerlike protrusions, spawned by many eukaryotic cells, to probe and interact with their environments. Polymerization dynamics of actin filaments, comprising the structural core of filopodia, largely determine their instantaneous lengths and overall lifetimes. The polymerization reactions at the filopodial tip require transport of G-actin, which enter the filopodial tube from the filopodial base and diffuse toward the filament barbed ends near the tip. Actin filaments are mechanically coupled into a tight bundle by cross-linker proteins. Interestingly, many of these proteins are relatively short, restricting the free diffusion of cytosolic G-actin throughout the bundle and, in particular, its penetration into the bundle core. To investigate the effect of steric restrictions on G-actin diffusion by the porous structure of filopodial actin filament bundle, we used a particle-based stochastic simulation approach. We discovered that excluded volume interactions result in partial and the...
Mechanical Models of Microtubule Bundle Collapse in Alzheimer's Disease
Sendek, Austin; Singh, Rajiv; Cox, Daniel
2013-03-01
Amyloid-beta aggregates initiate Alzheimer's disease, and downstream trigger degradation of tau proteins that act as microtubule bundle stabilizers and mechanical spacers. Currently it is unclear which of tau cutting by proteases, tau phosphorylation, or tau aggregation are responsible for cytoskeleton degradation., We construct a percolation simulation of the microtubule bundle using a molecular spring model for the taus and including depletion force attraction between microtubules and membrane/actin cytoskeletal surface tension. The simulation uses a fictive molecular dynamics to model the motion of the individual microtubules within the bundle as a result of random tau removal, and calculates the elastic modulus of the bundle as the tau concentration falls. We link the tau removal steps to kinetic tau steps in various models of tau degradation. Supported by US NSF Grant DMR 1207624
Introductory lectures on fibre bundles and topology for physicists
Energy Technology Data Exchange (ETDEWEB)
Thomas, G.H.
1978-05-01
These lectures may provide useful background material for understanding gauge theories, particularly the nonperturbative effects such as instantons and monopoles. The mathematical language of topology and fibre bundles is introduced.
Improved Conjugate Gradient Bundle Adjustment of Dunhuang Wall Painting Images
Hu, K.; Huang, X.; You, H.
2017-09-01
Bundle adjustment with additional parameters is identified as a critical step for precise orthoimage generation and 3D reconstruction of Dunhuang wall paintings. Due to the introduction of self-calibration parameters and quasi-planar constraints, the structure of coefficient matrix of the reduced normal equation is banded-bordered, making the solving process of bundle adjustment complex. In this paper, Conjugate Gradient Bundle Adjustment (CGBA) method is deduced by calculus of variations. A preconditioning method based on improved incomplete Cholesky factorization is adopt to reduce the condition number of coefficient matrix, as well as to accelerate the iteration rate of CGBA. Both theoretical analysis and experimental results comparison with conventional method indicate that, the proposed method can effectively conquer the ill-conditioned problem of normal equation and improve the calculation efficiency of bundle adjustment with additional parameters considerably, while maintaining the actual accuracy.
IMPROVED CONJUGATE GRADIENT BUNDLE ADJUSTMENT OF DUNHUANG WALL PAINTING IMAGES
Directory of Open Access Journals (Sweden)
K. Hu
2017-09-01
Full Text Available Bundle adjustment with additional parameters is identified as a critical step for precise orthoimage generation and 3D reconstruction of Dunhuang wall paintings. Due to the introduction of self-calibration parameters and quasi-planar constraints, the structure of coefficient matrix of the reduced normal equation is banded-bordered, making the solving process of bundle adjustment complex. In this paper, Conjugate Gradient Bundle Adjustment (CGBA method is deduced by calculus of variations. A preconditioning method based on improved incomplete Cholesky factorization is adopt to reduce the condition number of coefficient matrix, as well as to accelerate the iteration rate of CGBA. Both theoretical analysis and experimental results comparison with conventional method indicate that, the proposed method can effectively conquer the ill-conditioned problem of normal equation and improve the calculation efficiency of bundle adjustment with additional parameters considerably, while maintaining the actual accuracy.
Vertical, Bubbly, Cross-Flow Characteristics over Tube Bundles
Iwaki, C.; Cheong, K. H.; Monji, H.; Matsui, G.
2005-12-01
Two-phase flow over tube bundles is commonly observed in shell and tube-type heat exchangers. However, only limited amount of data concerning flow pattern and void fraction exists due to the flow complexity and the difficulties in measurement. The detailed flow structure in tube bundles needs to be understood for reliable and effective design. Therefore, the objective of this study was to clarify the two-phase structure of cross-flow in tube bundles by PIV. Experiments were conducted using two types of models, namely in-line and staggered arrays with a pitch-to-diameter ratio of 1.5. Each test section contains 20 rows of five 15 mm O.D. tubes in each row. The experiment’s data were obtained under very low void fraction (αtube bundles were described in terms of the velocity vector field, turbulence intensity and void fraction.
National Partnership for Maternal Safety: Consensus Bundle on Obstetric Hemorrhage.
Main, Elliott K; Goffman, Dena; Scavone, Barbara M; Low, Lisa Kane; Bingham, Debra; Fontaine, Patricia L; Gorlin, Jed B; Lagrew, David C; Levy, Barbara S
2015-07-01
Hemorrhage is the most frequent cause of severe maternal morbidity and preventable maternal mortality and therefore is an ideal topic for the initial national maternity patient safety bundle. These safety bundles outline critical clinical practices that should be implemented in every maternity unit. They are developed by multidisciplinary work groups of the National Partnership for Maternal Safety under the guidance of the Council on Patient Safety in Women's Health Care. The safety bundle is organized into four domains: Readiness, Recognition and Prevention, Response, and Reporting and System Learning. Although the bundle components may be adapted to meet the resources available in individual facilities, standardization within an institution is strongly encouraged. References contain sample resources and "Potential Best Practices" to assist with implementation.
National Partnership for Maternal Safety Consensus Bundle on Obstetric Hemorrhage.
Main, Elliott K; Goffman, Dena; Scavone, Barbara M; Low, Lisa Kane; Bingham, Debra; Fontaine, Patricia L; Gorlin, Jed B; Lagrew, David C; Levy, Barbara S
2015-01-01
Hemorrhage is the most frequent cause of severe maternal morbidity and preventable maternal mortality and therefore is an ideal topic for the initial national maternity patient safety bundle. These safety bundles outline critical clinical practices that should be implemented in every maternity unit. They are developed by multidisciplinary work groups of the National Partnership for Maternal Safety under the guidance of the Council on Patient Safety in Women's Health Care. The safety bundle is organized into 4 domains: Readiness, Recognition and Prevention, Response, and Reporting and Systems Learning. Although the bundle components may be adapted to meet the resources available in individual facilities, standardization within an institution is strongly encouraged. References contain sample resources and "Potential Best Practices" to assist with implementation.
Performance-based bundled payments: potential benefits and burdens.
Satin, David J; Miles, Justin
2009-10-01
Performance-based bundled payments have emerged as the most recent iteration of pay for performance. These are programs in which providers are paid a single fee for a set of evidenced-based services related to a diagnosis. The payments are typically linked to outcomes as well as other quality measures. This paper reviews two prominent bundled payment programs--PROMETHEUS and ProvenCare--and discusses the potential pitfalls of these approaches.
Identity-Based Cryptosystems for Enhanced Deployment of OSGi Bundles
Parrend, Pierre; Galice, Samuel; Frénot, Stéphane; Ubéda, Stéphane
2007-01-01
International audience; The OSGi platform is designed to make Java soft- ware extensible at runtime. This undeniably presents a great interest in several domains like embedded plat- forms or enterprise application servers. However, se- curing the deployment of the OSGi components, or bundles, proves to be a major challenge. The current approach consists in digitally signing the bundles and certifying the signature through a Public Key Infras- tructure. We propose to replace this technology wi...
Codimension-Three Bundle Singularities in F-Theory
Candelas, Philip; Florea, B; Morrison, Douglas Robert Ogston; Rajesh, G; Candelas, Philip; Diaconescu, Duiliu-Emanuel; Florea, Bogdan; Morrison, David R.; Rajesh, Govindan
2002-01-01
We study new nonperturbative phenomena in N=1 heterotic string vacua corresponding to pointlike bundle singularities in codimension three. These degenerations result in new four-dimensional infrared physics characterized by light solitonic states whose origin is explained in the dual F-theory model. We also show that such phenomena appear generically in $E_7 \\to E_6$ Higgsing and describe in detail the corresponding bundle transition.
Generalized holomorphic bundles and the B-field action
Hitchin, Nigel
2010-01-01
On a generalized complex manifold there is an associated definition of a generalized holomorphic bundle, introduced by Gualtieri. This notion in the case of an ordinary complex structure yields an object which we call a co-Higgs bundle and we consider the B-field action of a closed form of type (1,1), both local and global. The effect makes contact with both Nahm's equations and holomorphic gerbes.
Generalized holomorphic bundles and the B-field action
Hitchin, Nigel
2011-01-01
On a generalized complex manifold, there is an associated definition of a generalized holomorphic bundle, introduced by Gualtieri. In the case of an ordinary complex structure, this notion yields an object which we call a co-Higgs bundle, and we consider the B-field action of a closed form of type (1,1), both local and global. The effect makes contact with both Nahm's equations and holomorphic gerbes.
Simplified modeling of EM field coupling to complex cable bundles
Schetelig, B.; J. Keghie; Kanyou Nana, R.; Fichte, L.-O.; S. Potthast; Dickmann, S.
2010-01-01
In this contribution, the procedure "Equivalent Cable Bundle Method" is used for the simplification of large cable bundles, and it is extended to the application on differential signal lines. The main focus is on the reduction of twisted-pair cables. Furthermore, the process presented here allows to take into account cables with wires that are situated quite close to each other. The procedure is based on a new approach to calculate the geometry of the simplified cable and us...
Dunkl Operators as Covariant Derivatives in a Quantum Principal Bundle
Micho Đurđevich; Stephen Bruce Sontz
2011-01-01
A quantum principal bundle is constructed for every Coxeter group acting on a finite-dimensional Euclidean space $E$, and then a connection is also defined on this bundle. The covariant derivatives associated to this connection are the Dunkl operators, originally introduced as part of a program to generalize harmonic analysis in Euclidean spaces. This gives us a new, geometric way of viewing the Dunkl operators. In particular, we present a new proof of the commutativity of these operators amo...
Seiler, J. M.; Rameau, B.
Bundle sodium boiling in nominal geometry for different accident conditions is reviewed. Voiding of a subassembly is controlled by not only hydrodynamic effects but mainly by thermal effects. There is a strong influence of the thermal inertia of the bundle material compared to the sodium thermal inertia. Flow instability, during a slow transient, can be analyzed with numerical tools and estimated using simplified approximations. Stable boiling operational conditions under bundle mixed convection (natural convection in the reactor) can be predicted. Voiding during a fast transient can be approximated from single channel calculations. The phenomenology of boiling behavior for a subassembly with inlet completely blocked, submitted to decay heat and lateral cooling; two-phase sodium flow pressure drop in a tube of large hydraulic diameter under adiabatic conditions; critical flow phenomena and voiding rate under high power, slow transient conditions; and onset of dry out under local boiling remains problematical.
BiSet: Semantic Edge Bundling with Biclusters for Sensemaking.
Sun, Maoyuan; Mi, Peng; North, Chris; Ramakrishnan, Naren
2016-01-01
Identifying coordinated relationships is an important task in data analytics. For example, an intelligence analyst might want to discover three suspicious people who all visited the same four cities. Existing techniques that display individual relationships, such as between lists of entities, require repetitious manual selection and significant mental aggregation in cluttered visualizations to find coordinated relationships. In this paper, we present BiSet, a visual analytics technique to support interactive exploration of coordinated relationships. In BiSet, we model coordinated relationships as biclusters and algorithmically mine them from a dataset. Then, we visualize the biclusters in context as bundled edges between sets of related entities. Thus, bundles enable analysts to infer task-oriented semantic insights about potentially coordinated activities. We make bundles as first class objects and add a new layer, "in-between", to contain these bundle objects. Based on this, bundles serve to organize entities represented in lists and visually reveal their membership. Users can interact with edge bundles to organize related entities, and vice versa, for sensemaking purposes. With a usage scenario, we demonstrate how BiSet supports the exploration of coordinated relationships in text analytics.
Oscillation of carbon molecules inside carbon nanotube bundles
Thamwattana, Ngamta; Cox, Barry J.; Hill, James M.
2009-04-01
In this paper, we investigate the mechanics of a nanoscaled gigahertz oscillator comprising a carbon molecule oscillating within the centre of a uniform concentric ring or bundle of carbon nanotubes. Two kinds of oscillating molecules are considered, which are a carbon nanotube and a C60 fullerene. Using the Lennard-Jones potential and the continuum approach, we obtain a relation between the bundle radius and the radii of the nanotubes forming the bundle, as well as the optimum bundle size which gives rise to the maximum oscillatory frequency for both the nanotube-bundle and the C60-bundle oscillators. While previous studies in this area have been undertaken through molecular dynamics simulations, this paper emphasizes the use of applied mathematical modelling techniques, which provides considerable insight into the underlying mechanisms of the nanoscaled oscillators. The paper presents a synopsis of the major results derived in detail by the present authors (Cox et al 2007 Proc. R. Soc. A 464 691-710 and Cox et al 2007 J. Phys. A: Math. Theor. 40 13197-208).
New strict left bundle branch block criteria reflect left ventricular activation differences
DEFF Research Database (Denmark)
Emerek, Kasper Janus Grønn; Risum, Niels; Hjortshøj, Søren Pihlkjær;
2015-01-01
applying new strict ECG criteria subsequent rates of response in DCM were 18/19 (95%) and in IHD of 18/23 (78%) respectively, p... ventricular electrical delay (RV-LV-IED) was measured. Response to CRT was defined as ≥15% decrease in left ventricular end-systolic volume. RESULTS: Eighteen of 20 (90%) patients with non-ischemic dilated cardiomyopathy (DCM) and 18 of 29 (62%) with ischemic heart disease (IHD) responded to CRT, p.... CONCLUSION: Interventricular electrical delay predicts left ventricular remodeling after CRT and new, strict ECG criteria of LBBB are superior in predicting remodeling....
A Clinical and Follow-up Study of Right and Left Bundle Branch Block
1974-09-03
acute myocardial infarction and one with chronic !ung disease and cor pulmonale ). Of the nine BBBB subjects with an initial diagnosis of hyperten...complicated In cor pulmonale . and for one, the cause of death was not available. Of the nine LBBB patients who died, five died of conditions related...the RBBB group, i and 2’r had cor - onarx heart disease and hypertension, respectively; in LBBB subjects, 9 and ~’i had coronarv heart disease and h
OPTIMIZING THE DISTRIBUTION OF TIE POINTS FOR THE BUNDLE ADJUSTMENT OF HRSC IMAGE MOSAICS
Directory of Open Access Journals (Sweden)
J. Bostelmann
2017-07-01
Full Text Available For a systematic mapping of the Martian surface, the Mars Express orbiter is equipped with a multi-line scanner: Since the beginning of 2004 the High Resolution Stereo Camera (HRSC regularly acquires long image strips. By now more than 4,000 strips covering nearly the whole planet are available. Due to the nine channels, each with different viewing direction, and partly with different optical filters, each strip provides 3D and color information and allows the generation of digital terrain models (DTMs and orthophotos. To map larger regions, neighboring HRSC strips can be combined to build DTM and orthophoto mosaics. The global mapping scheme Mars Chart 30 is used to define the extent of these mosaics. In order to avoid unreasonably large data volumes, each MC-30 tile is divided into two parts, combining about 90 strips each. To ensure a seamless fit of these strips, several radiometric and geometric corrections are applied in the photogrammetric process. A simultaneous bundle adjustment of all strips as a block is carried out to estimate their precise exterior orientation. Because size, position, resolution and image quality of the strips in these blocks are heterogeneous, also the quality and distribution of the tie points vary. In absence of ground control points, heights of a global terrain model are used as reference information, and for this task a regular distribution of these tie points is preferable. Besides, their total number should be limited because of computational reasons. In this paper, we present an algorithm, which optimizes the distribution of tie points under these constraints. A large number of tie points used as input is reduced without affecting the geometric stability of the block by preserving connections between strips. This stability is achieved by using a regular grid in object space and discarding, for each grid cell, points which are redundant for the block adjustment. The set of tie points, filtered by the
Optimizing the Distribution of Tie Points for the Bundle Adjustment of HRSC Image Mosaics
Bostelmann, J.; Breitkopf, U.; Heipke, C.
2017-07-01
For a systematic mapping of the Martian surface, the Mars Express orbiter is equipped with a multi-line scanner: Since the beginning of 2004 the High Resolution Stereo Camera (HRSC) regularly acquires long image strips. By now more than 4,000 strips covering nearly the whole planet are available. Due to the nine channels, each with different viewing direction, and partly with different optical filters, each strip provides 3D and color information and allows the generation of digital terrain models (DTMs) and orthophotos. To map larger regions, neighboring HRSC strips can be combined to build DTM and orthophoto mosaics. The global mapping scheme Mars Chart 30 is used to define the extent of these mosaics. In order to avoid unreasonably large data volumes, each MC-30 tile is divided into two parts, combining about 90 strips each. To ensure a seamless fit of these strips, several radiometric and geometric corrections are applied in the photogrammetric process. A simultaneous bundle adjustment of all strips as a block is carried out to estimate their precise exterior orientation. Because size, position, resolution and image quality of the strips in these blocks are heterogeneous, also the quality and distribution of the tie points vary. In absence of ground control points, heights of a global terrain model are used as reference information, and for this task a regular distribution of these tie points is preferable. Besides, their total number should be limited because of computational reasons. In this paper, we present an algorithm, which optimizes the distribution of tie points under these constraints. A large number of tie points used as input is reduced without affecting the geometric stability of the block by preserving connections between strips. This stability is achieved by using a regular grid in object space and discarding, for each grid cell, points which are redundant for the block adjustment. The set of tie points, filtered by the algorithm, shows a more
Combustor having mixing tube bundle with baffle arrangement for directing fuel
Energy Technology Data Exchange (ETDEWEB)
Hughes, Michael John; McConnaughhay, Johnie Franklin
2016-08-23
A combustor includes a tube bundle that extends radially across at least a portion of the combustor. The tube bundle includes an upstream surface axially separated from a downstream surface, and a plurality of tubes extend from the upstream surface through the downstream surface to provide fluid communication through the tube bundle. A barrier extends radially inside the tube bundle between the upstream and downstream surfaces, and a baffle extends axially inside the tube bundle between the upstream surface and the barrier.
SiPM-PET with a short optical fiber bundle for simultaneous PET-MR imaging.
Hong, Seong Jong; Kang, Han Gyoo; Ko, Guen Bae; Song, In Chan; Rhee, June-Tak; Lee, Jae Sung
2012-06-21
For positron emission tomography (PET) inserts to magnetic resonance imaging (MRI) applications, optical fibers have been used for some time to transfer scintillation photons to photomultiplier tubes positioned outside the fringe magnetic field. We previously proposed a novel utilization of an optical fiber for good radio frequency (RF) transmission from body coils to an imaging object. Optical fiber bundles between silicon photomultipliers (SiPM) and scintillation crystals provide an increased spacing between RF-shielded electronics boxes, facilitating RF passage from the body RF coils to imaging objects. In this paper, we present test results of a SiPM-PET system with a short optical fiber bundle for simultaneous PET-MR imaging. We built the SiPM-PET system which consisted of 12 SiPM-PET modules; each module was assembled with a lutetium yttrium oxyorthosilicatecrystal block, a 31 mm optical fiber bundle, a Hamamatsu multi-pixel photon counter S11064-050P and a signal processing box shielded with copper. The SiPM-PET system, with a face-to-face distance of 71 mm, was placed inside a 3 T MRI. A small surface coil placed inside the SiPM-PET system was used to receive the signal from phantoms while the body RF coil transmitted the RF pulses. The SiPM-PET system showed little performance degradation during the simultaneous PET-MR imaging and it caused no significant degradation of MR images with turbo spin echo (TSE), gradient echo or 3D spoiled gradient recalled sequences. Echo planar imaging MR images with and without the SiPM-PET inside the MR scanner were significantly worse than the images obtained with the TSE sequence.
Histones bundle F-actin filaments and affect actin structure.
Blotnick, Edna; Sol, Asaf; Muhlrad, Andras
2017-01-01
Histones are small polycationic proteins complexed with DNA located in the cell nucleus. Upon apoptosis they are secreted from the cells and react with extracellular polyanionic compounds. Actin which is a polyanionic protein, is also secreted from necrotic cells and interacts with histones. We showed that both histone mixture (histone type III) and the recombinant H2A histone bundles F-actin, increases the viscosity of the F-actin containing solution and polymerizes G-actin. The histone-actin bundles are relatively insensitive to increase of ionic strength, unlike other polycation, histatin, lysozyme, spermine and LL-37 induced F-actin bundles. The histone-actin bundles dissociate completely only in the presence of 300-400 mM NaCl. DNA, which competes with F-actin for histones, disassembles histone induced actin bundles. DNase1, which depolymerizes F- to G-actin, actively unbundles the H2A histone induced but slightly affects the histone mixture induced actin bundles. Cofilin decreases the amount of F-actin sedimented by low speed centrifugation, increases light scattering and viscosity of F-actin-histone mixture containing solutions and forms star like superstructures by copolymerizing G-actin with H2A histone. The results indicate that histones are tightly attached to F-actin by strong electrostatic and hydrophobic forces. Since both histones and F-actin are present in the sputum of patients with cystic fibrosis, therefore, the formation of the stable histone-actin bundles can contribute to the pathology of this disease by increasing the viscosity of the sputum. The actin-histone interaction in the nucleus might affect gene expression.
Ultrasound guided supraclavicular block.
LENUS (Irish Health Repository)
Hanumanthaiah, Deepak
2013-09-01
Ultrasound guided regional anaesthesia is becoming increasingly popular. The supraclavicular block has been transformed by ultrasound guidance into a potentially safe superficial block. We reviewed the techniques of performing supraclavicular block with special focus on ultrasound guidance.
Börlin, Niclas; Grussenmeyer, Pierre
2016-06-01
The aim of this paper is to investigate whether the Matlab-based Damped Bundle Adjustment Toolbox (DBAT) can be used to provide independent verification of the BA computation of two popular software—PhotoModeler (PM) and PhotoScan (PS). For frame camera data sets with lens distortion, DBAT is able to reprocess and replicate subsets of PM results with high accuracy. For lens-distortion-free data sets, DBAT can furthermore provide comparative results between PM and PS. Data sets for the discussed projects are available from the authors. The use of an external verification tool such as DBAT will enable users to get an independent verification of the computations of their software. In addition, DBAT can provide computation of quality parameters such as estimated standard deviations, correlation between parameters, etc., something that should be part of best practice for any photogrammetric software. Finally, as the code is free and open-source, users can add computations of their own.
Directory of Open Access Journals (Sweden)
Sandra Umeda Sasaki
2008-01-01
Full Text Available INTRODUCTION: Anterior cruciate ligament ruptures are frequent, especially in sports. Surgical reconstruction with autologous grafts is widely employed in the international literature. Controversies remain with respect to technique variations as continuous research for improvement takes place. One of these variations is the anatomical double bundle technique, which is performed instead of the conventional single bundle technique. More recently, there has been a tendency towards positioning the two bundles through double bone tunnels in the femur and tibia (anatomical reconstruction. OBJECTIVES: To compare, through biomechanical tests, the practice of anatomical double bundle anterior cruciate ligament reconstruction with a patellar graft to conventional single bundle reconstruction with the same amount of patellar graft in a paired experimental cadaver study. METHODS: Nine pairs of male cadaver knees ranging in age from 44 to 63 years were randomized into two groups: group A (single bundle and group B (anatomical reconstruction. Each knee was biomechanically tested under three conditions: intact anterior cruciate ligament, reconstructed anterior cruciate ligament, and injured anterior cruciate ligament. Maximum anterior dislocation, rigidity, and passive internal tibia rotation were recorded with knees submitted to a 100 N horizontal anterior dislocation force applied to the tibia with the knees at 30, 60 and 90 degrees of flexion. RESULTS: There were no differences between the two techniques for any of the measurements by ANOVA tests. CONCLUSION: The technique of anatomical double bundle reconstruction of the anterior cruciate ligament with bone-patellar tendon-bone graft has a similar biomechanical behavior with regard to anterior tibial dislocation, rigidity, and passive internal tibial rotation.
Improvements to Wire Bundle Thermal Modeling for Ampacity Determination
Rickman, Steve L.; Iannello, Christopher J.; Shariff, Khadijah
2017-01-01
Determining current carrying capacity (ampacity) of wire bundles in aerospace vehicles is critical not only to safety but also to efficient design. Published standards provide guidance on determining wire bundle ampacity but offer little flexibility for configurations where wire bundles of mixed gauges and currents are employed with varying external insulation jacket surface properties. Thermal modeling has been employed in an attempt to develop techniques to assist in ampacity determination for these complex configurations. Previous developments allowed analysis of wire bundle configurations but was constrained to configurations comprised of less than 50 elements. Additionally, for vacuum analyses, configurations with very low emittance external jackets suffered from numerical instability in the solution. A new thermal modeler is presented allowing for larger configurations and is not constrained for low bundle infrared emissivity calculations. Formulation of key internal radiation and interface conductance parameters is discussed including the effects of temperature and air pressure on wire to wire thermal conductance. Test cases comparing model-predicted ampacity and that calculated from standards documents are presented.
Variable recruitment in bundles of miniature pneumatic artificial muscles.
DeLaHunt, Sylvie A; Pillsbury, Thomas E; Wereley, Norman M
2016-09-13
The natural compliance and force generation properties of pneumatic artificial muscles (PAMs) allow them to operate like human muscles in anthropomorphic robotic manipulators. Traditionally, manipulators use a single PAM or multiple PAMs actuated in unison in place of a human muscle. However, these standard manipulators can experience significant efficiency losses when operated outside their target performance ranges at low actuation pressures. This study considers the application of a variable recruitment control strategy to a parallel bundle of miniature PAMs as an attempt to mimic the selective recruitment of motor units in a human muscle. Bundles of miniature PAMs are experimentally characterized, their actuation behavior is modeled, and the efficiency gains and losses associated with the application of a variable recruitment control strategy are assessed. This bio-inspired control strategy allows muscle bundles to operate the fewest miniature PAMs necessary to achieve a desired performance objective, improving the muscle bundle's operating efficiency over larger ranges of force generation and displacement. The study also highlights the need for improved PAM fabrication techniques to facilitate the production of identical miniature PAMs for inclusion in muscle bundles.
Thermal hydraulics of rod bundles: The effect of eccentricity
Energy Technology Data Exchange (ETDEWEB)
Chauhan, Amit K., E-mail: amit_fmlab@yahoo.co.in [Fluid Mechanics Laboratory, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai 600036 (India); Prasad, B.V.S.S.S., E-mail: prasad@iitm.ac.in [Thermal Turbomachines Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Patnaik, B.S.V., E-mail: bsvp@iitm.ac.in [Fluid Mechanics Laboratory, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai 600036 (India)
2013-10-15
Highlights: • Present CFD investigation explores, whole bundle eccentricity for the first time. • Fluid flow and thermal characteristics in various subchannels are analyzed. • Mass flux distribution is particularly analyzed to study eccentricity effect. • Higher eccentricity resulted in a shoot up in rod surface temperature distribution. • Both tangential and radial flow in rod bundles has resulted due to eccentricity. -- Abstract: The effect of eccentricity on the fluid flow and heat transfer through a 19-rod bundle is numerically carried out. When the whole bundle shifts downwards with respect to the outer (pressure) tube, flow redistribution happens. This in turn is responsible for changes in mass flux, pressure and differential flow development in various subchannels. The heat flux imposed on the surface of the fuel rods and the mass flux through the subchannels determines the coolant outlet temperatures. The simulations are performed for a coolant flow Reynolds number of 4 × 10{sup 5}. For an eccentricity value of 0.7, the mass flux in the bottom most subchannel (l) was found to decrease by 10%, while the surface temperature of the fuel rod in the vicinity of this subchannel increased by 250% at the outlet section. Parameters of engineering interest including skin friction coefficient, Nusselt number, etc., have been systematically explored to study the effect of eccentricity on the rod bundle.
Dynamic response of fiber bundle under transverse impact.
Energy Technology Data Exchange (ETDEWEB)
Lu, Wei-Yang; Song, Bo
2010-03-01
There has been a very high demand in developing efficient soft body armors to protect the military and law enforcement personnel from ballistic or explosive attack. As a basic component in the soft body armor, fibers or fiber bundles play a key role in the performance against ballistic impact. In order to study the ballistic-resistant mechanism of the soft body armor, it is desirable to understand the dynamic response of the fiber bundle under transverse impact. Transverse wave speed is one important parameter because a faster transverse wave speed can make the impact energy dissipate more quickly. In this study, we employed split Hopkinson pressure bar (SHPB) to generate constant high-speed impact on a Kevlar fiber bundle in the transverse direction. The deformation of the fiber bundle was photographed with high-speed digital cameras. The transverse wave speeds were experimentally measured at various transverse impact velocities. The experimental results can also be used to quantitatively verify the current analytical models or to develop new models to describe the dynamic response of fiber bundle under transverse impact.
Pressure Loss across Tube Bundles in Two-phase Flow
Energy Technology Data Exchange (ETDEWEB)
Sim, Woo Gun; Banzragch, Dagdan [Hannam Univ., Daejon (Korea, Republic of)
2016-03-15
An analytical model was developed by Sim to estimate the two-phase damping ratio for upward two-phase flow perpendicular to horizontal tube bundles. The parameters of two-phase flow, such as void fraction and pressure loss evaluated in the model, were calculated based on existing experimental formulations. However, it is necessary to implement a few improvements in the formulations for the case of tube bundles. For the purpose of the improved formulation, we need more information about the two-phase parameters, which can be found through experimental test. An experiment is performed with a typical normal square array of cylinders subjected to the two-phase flow of air-water in the tube bundles, to calculate the two-phase Euler number and the two-phase friction multiplier. The pitch-to-diameter ratio is 1.35 and the diameter of cylinder is 18mm. Pressure loss along the flow direction in the tube bundles is measured with a pressure transducer and data acquisition system to calculate the two-phase Euler number and the two-phase friction multiplier. The void fraction model by Feenstra et al. is used to estimate the void fraction of the two-phase flow in tube bundles. The experimental results of the two phase friction multiplier and two-phase Euler number for homogeneous and non-homogeneous two-phase flows are compared and evaluated against the analytical results given by Sim's model.
Ecosystem service bundles for analyzing tradeoffs in diverse landscapes
Raudsepp-Hearne, C.; Peterson, G. D.; Bennett, E. M.
2010-01-01
A key challenge of ecosystem management is determining how to manage multiple ecosystem services across landscapes. Enhancing important provisioning ecosystem services, such as food and timber, often leads to tradeoffs between regulating and cultural ecosystem services, such as nutrient cycling, flood protection, and tourism. We developed a framework for analyzing the provision of multiple ecosystem services across landscapes and present an empirical demonstration of ecosystem service bundles, sets of services that appear together repeatedly. Ecosystem service bundles were identified by analyzing the spatial patterns of 12 ecosystem services in a mixed-use landscape consisting of 137 municipalities in Quebec, Canada. We identified six types of ecosystem service bundles and were able to link these bundles to areas on the landscape characterized by distinct social–ecological dynamics. Our results show landscape-scale tradeoffs between provisioning and almost all regulating and cultural ecosystem services, and they show that a greater diversity of ecosystem services is positively correlated with the provision of regulating ecosystem services. Ecosystem service-bundle analysis can identify areas on a landscape where ecosystem management has produced exceptionally desirable or undesirable sets of ecosystem services. PMID:20194739
Iriuchishima, Takanori; Ryu, Keinosuke; Okano, Tatsumasa; Suruga, Makoto; Aizawa, Shin; Fu, Freddie H
2017-05-01
The purpose of this study was to reveal the degree of muscle recovery and report the clinical results of anatomical single-bundle ACL reconstruction using a quadriceps autograft. Twenty subjects undergoing anatomical single-bundle ACL reconstruction using a quadriceps autograft were included in this study. A 5-mm-wide, 8-cm-long graft, involving the entire layer of the quadriceps tendon, was harvested without bone block. The average graft diameter was 8.1 ± 1.4 mm. An initial tension of 30 N was applied. The femoral tunnel was created from the far-medial portal. Each femoral and tibial tunnel was created close to the antero-medial bundle insertion site. For the evaluation of muscle recovery (quadriceps and hamstring), a handheld dynamometer was used. The evaluation of muscle recovery was performed pre-operatively, and at 3, 6, 9, and 12 months after surgery. Muscle recovery data were calculated as a percentage of leg strength in the non-operated leg. Anterior tibial translation (ATT), pivot shift test, and IKDC score were evaluated. The average quadriceps strength pre-operatively, and at 3, 6, 9, and 12 months after ACL reconstruction was 90.5 ± 19, 67.8 ± 21.4, 84 ± 17.5, and 85.1 ± 12.6 %, respectively. The average hamstring strength pre-operatively, and at 3, 6, 9, and 12 months after ACL reconstruction was 99.5 ± 13.7, 78.7 ± 11.4, 90.5 ± 19, and 96.7 ± 13.8 %, respectively. ATT pre-operatively and at 12 months after surgery was 5.4 ± 1.3 and 1.0 ± 0.8 mm, respectively. No subjects exhibited positive pivot shift after surgery. Within 6 months following surgery, quadriceps hypotrophy was observed in all subjects. However, the hypotrophy had recovered at 12 months following surgery. No subjects complained of donor site pain after surgery. Anatomical single-bundle ACL reconstruction using a quadriceps autograft resulted in equivalent level of muscle recovery and knee stability when compared with previously reported ACL
Failure of a MEA reclaimer tube bundle due to corrosion
Energy Technology Data Exchange (ETDEWEB)
Shaban, H.; Abdo, M.S.E.; Lal, D.P.
1988-08-01
The removal of sulphur compounds from natural gas used in ammonia production is carried out by scrubbing with monoethanol amine (MEA). To avoid build up of corrosion and degradation products, a portion of the circulating MEA solution is passed through a reclaimer. This is essentially a kettle-type reboiler with a tube bundle made of 316L stainless steel. Occasional failures of the tube bundle due to pitting corrosion have been reported. It is suggested that the excessive pitting corrosion observed on the upper rows of the tube bundle could be partly due to high steam temperature but mainly due to the liquid level falling below the tubes leaving an accumulation of corrosive degradation products on the exposed surfaces, normally these corrosive products remain diluted in the MEA solution and cause little corrosion of the covered tubes. Their concentration on the dry upper layers of the hot metal tubes, however, leads to excessive corrosion. (U.K.).
On the motives of moduli of chains and Higgs bundles
García-Prada, Oscar; Schmitt, Alexander
2011-01-01
We take another approach to Hitchin's strategy of computing the cohomology of moduli spaces of Higgs bundles by localization with respect to the circle-action. Our computation is done in the dimensional completion of the Grothendieck ring of varieties and starts by describing the classes of moduli stacks of chains rather than their coarse moduli spaces. As an application we show that the n-torsion of the Jacobian acts trivially on the middle dimensional cohomology of the moduli space of twisted SL_n-Higgs-bundles of degree coprime to n and we give an explicit formula for the motive of the moduli space of Higgs bundles of rank 4 and odd degree. This provides new evidence for a conjecture of Hausel and Rodr\\'iguez-Villegas. Along the way we find explicit recursion formulas for the motives of several types of moduli spaces of stable chains.
Rheology of semiflexible bundle networks with transient linkers.
Müller, Kei W; Bruinsma, Robijn F; Lieleg, Oliver; Bausch, Andreas R; Wall, Wolfgang A; Levine, Alex J
2014-06-13
We present a theoretical and computational analysis of the rheology of networks made up of bundles of semiflexible filaments bound by transient cross-linkers. Such systems are ubiquitous in the cytoskeleton and can be formed in vitro using filamentous actin and various cross-linkers. We find that their high-frequency rheology is characterized by a scaling behavior that is quite distinct from that of networks of the well-studied single semiflexible filaments. This regime can be understood theoretically in terms of a length-scale-dependent bending modulus for bundles. Next, we observe new dissipative dynamics associated with the shear-induced disruption of the network at intermediate frequencies. Finally, at low frequencies, we encounter a region of non-Newtonian rheology characterized by power-law scaling. This regime is dominated by bundle dissolution and large-scale rearrangements of the network driven by equilibrium thermal fluctuations.
DTI Image Registration under Probabilistic Fiber Bundles Tractography Learning
Lei, Tao; Fan, Yangyu; Zhang, Xiuwei
2016-01-01
Diffusion Tensor Imaging (DTI) image registration is an essential step for diffusion tensor image analysis. Most of the fiber bundle based registration algorithms use deterministic fiber tracking technique to get the white matter fiber bundles, which will be affected by the noise and volume. In order to overcome the above problem, we proposed a Diffusion Tensor Imaging image registration method under probabilistic fiber bundles tractography learning. Probabilistic tractography technique can more reasonably trace to the structure of the nerve fibers. The residual error estimation step in active sample selection learning is improved by modifying the residual error model using finite sample set. The calculated deformation field is then registered on the DTI images. The results of our proposed registration method are compared with 6 state-of-the-art DTI image registration methods under visualization and 3 quantitative evaluation standards. The experimental results show that our proposed method has a good comprehensive performance.
Narrow muon bundles from muon pair production in rock
Kudryavtsev, V A; Spooner, N J C
1999-01-01
We revise the process of muon pair production by high-energy muons in rock using the recently published cross-section. The three- dimensional Monte Carlo code MUSIC has been used to obtain the characteristics of the muon bundles initiated via this process. We have compared them with those of conventional muon bundles initiated in the atmosphere and shown that large underground detectors, capable of collecting hundreds of thousands of multiple muon events, can discriminate statistically muon induced bundles from conventional ones. However, we find that the enhancement of the measured muon decoherence function over that predicted at small distances, recently reported by the MACRO experiment, cannot be explained by the effect of muon pair production alone, unless its cross-section is underestimated by a factor of 3. (20 refs).
Narrow muon bundles from muon pair production in rock
Kudryavtsev, V A; Spooner, N J C; 10.1016/S0370-2693(99)01378-7
2009-01-01
We revise the process of muon pair production by high-energy muons in rock using the recently published cross-section. The three-dimensional Monte Carlo code MUSIC has been used to obtain the characteristics of the muon bundles initiated via this process. We have compared them with those of conventional muon bundles initiated in the atmosphere and shown that large underground detectors, capable of collecting hundreds of thousands of multiple muon events, can discriminate statistically muon induced bundles from conventional ones. However, we find that the enhancement of the measured muon decoherence function over that predicted at small distances, recently reported by the MACRO experiment, cannot be explained by the effect of muon pair production alone, unless its cross-section is underestimated by a factor of 3.
High-order synchronization of hair cell bundles
Levy, Michael; Molzon, Adrian; Lee, Jae-Hyun; Kim, Ji-Wook; Cheon, Jinwoo; Bozovic, Dolores
2016-12-01
Auditory and vestibular hair cell bundles exhibit active mechanical oscillations at natural frequencies that are typically lower than the detection range of the corresponding end organs. We explore how these noisy nonlinear oscillators mode-lock to frequencies higher than their internal clocks. A nanomagnetic technique is used to stimulate the bundles without an imposed mechanical load. The evoked response shows regimes of high-order mode-locking. Exploring a broad range of stimulus frequencies and intensities, we observe regions of high-order synchronization, analogous to Arnold Tongues in dynamical systems literature. Significant areas of overlap occur between synchronization regimes, with the bundle intermittently flickering between different winding numbers. We demonstrate how an ensemble of these noisy spontaneous oscillators could be entrained to efficiently detect signals significantly above the characteristic frequencies of the individual cells.
Symposium on Singularities, Representation of Algebras, and Vector Bundles
Trautmann, Günther
1987-01-01
It is well known that there are close relations between classes of singularities and representation theory via the McKay correspondence and between representation theory and vector bundles on projective spaces via the Bernstein-Gelfand-Gelfand construction. These relations however cannot be considered to be either completely understood or fully exploited. These proceedings document recent developments in the area. The questions and methods of representation theory have applications to singularities and to vector bundles. Representation theory itself, which had primarily developed its methods for Artinian algebras, starts to investigate algebras of higher dimension partly because of these applications. Future research in representation theory may be spurred by the classification of singularities and the highly developed theory of moduli for vector bundles. The volume contains 3 survey articles on the 3 main topics mentioned, stressing their interrelationships, as well as original research papers.
4d SCFTs from negative-degree line bundles
Nardoni, Emily
2016-01-01
We construct 4d $\\mathcal{N}=1$ quantum field theories by compactifying the (2,0) theories on a Riemann surface with genus $g$ and $n$ punctures, where the normal bundle decomposes into a sum of two line bundles with possibly negative degrees $p$ and $q$. Until recently, the only available field-theoretic constructions required the line bundle degrees to be nonnegative, although supergravity solutions were constructed in the literature for the zero-puncture case for all $p$ and $q$. Here, we provide field-theoretic constructions and computations of the central charges of 4d $\\mathcal{N}=1$ SCFTs that are the IR limit of M5-branes wrapping a surface with general $p$ or $q$ negative, for general genus $g$ and number of maximal punctures $n$.
Simulation of bundle test Quench-12 with integral code MELCOR
Energy Technology Data Exchange (ETDEWEB)
Duspiva, J. [Nuclear Research Inst., Rez plc (Czech Republic)
2011-07-01
The past NRI analyses cover the Quench-01, Quench-03 and Quench-06 with version MELCOR 1.8.5 (including reflood model), and Quench-01 and Quench-11 tests with the latest version MELCOR 1.8.6. The Quench-12 test is specific, because it has different bundle configuration related to the VVER bundle configuration with hexagonal grid of pins and also used E110 cladding material. Specificity of Quench-12 test is also in the used material of fuel rod cladding - E110. The test specificities are a reason for the highest concern, because the VVER reactors are operated in the Czech Republic. The new input model was developed with the taking into account all experience from previous simulations of the Quench bundle tests. The recent version MELCOR 1.8.6 YU{sub 2}911 was used for the simulation with slightly modified ELHEAT package. Sensitivity studies on input parameters and oxidation kinetics were performed. (author)
Multi-scale strain-stiffening of semiflexible bundle networks
Piechocka, I K; Broedersz, C P; Kurniawan, N A; MacKintosh, F C; Koenderink, G H
2015-01-01
Bundles of polymer filaments are responsible for the rich and unique mechanical behaviors of many biomaterials, including cells and extracellular matrices. In fibrin biopolymers, whose nonlinear elastic properties are crucial for normal blood clotting, protofibrils self-assemble and bundle to form networks of semiflexible fibers. Here we show that the extraordinary strain-stiffening response of fibrin networks is a direct reflection of the hierarchical architecture of the fibrin fibers. We measure the rheology of networks of unbundled protofibrils and find excellent agreement with an affine model of extensible wormlike polymers. By direct comparison with these data, we show that physiological fibrin networks composed of thick fibers can be modeled as networks of tight protofibril bundles. We demonstrate that the tightness of coupling between protofibrils in the fibers can be tuned by the degree of enzymatic intermolecular crosslinking by the coagulation Factor XIII. Furthermore, at high stress, the protofibri...
Real Parabolic Vector Bundles over a Real Curve
Indian Academy of Sciences (India)
Sanjay Amrutiya
2014-02-01
We define real parabolic structures on real vector bundles over a real curve. Let $(X, _X)$ be a real curve, and let $S\\subset X$ be a non-empty finite subset of such that $_X(S) = S$. Let ≥ 2 be an integer. We construct an -fold cyclic cover : $Y→ X$ in the category of real curves, ramified precisely over each point of , and with the property that for any element of the Galois group , and any $y\\in Y$, one has $_Y(gy) = g^{-1}_Y(y)$. We established an equivalence between the category of real parabolic vector bundles on $(X,_X)$ with real parabolic structure over , all of whose weights are integral multiples of 1/, and the category of real -equivariant vector bundles on $(Y, _Y)$.
The Family Problem: Hints from Heterotic Line Bundle Models
Constantin, Andrei; Mishra, Challenger
2015-01-01
Within the class of heterotic line bundle models, we argue that N=1 vacua which lead to a small number of low-energy chiral families are preferred. By imposing an upper limit on the volume of the internal manifold, as required in order to obtain finite values of the four-dimensional gauge couplings, and validity of the supergravity approximation we show that, for a given manifold, only a finite number of line bundle sums are consistent with supersymmetry. By explicitly scanning over this finite set of line bundle models on certain manifolds we show that, for a sufficiently small volume of the internal manifold, the family number distribution peaks at small values, consistent with three chiral families. The relation between the maximal number of families and the gauge coupling is discussed, which hints towards a possible explanation of the family problem.
Magnetic Propulsion of Microswimmers with DNA-Based Flagellar Bundles.
Maier, Alexander M; Weig, Cornelius; Oswald, Peter; Frey, Erwin; Fischer, Peer; Liedl, Tim
2016-02-10
We show that DNA-based self-assembly can serve as a general and flexible tool to construct artificial flagella of several micrometers in length and only tens of nanometers in diameter. By attaching the DNA flagella to biocompatible magnetic microparticles, we provide a proof of concept demonstration of hybrid structures that, when rotated in an external magnetic field, propel by means of a flagellar bundle, similar to self-propelling peritrichous bacteria. Our theoretical analysis predicts that flagellar bundles that possess a length-dependent bending stiffness should exhibit a superior swimming speed compared to swimmers with a single appendage. The DNA self-assembly method permits the realization of these improved flagellar bundles in good agreement with our quantitative model. DNA flagella with well-controlled shape could fundamentally increase the functionality of fully biocompatible nanorobots and extend the scope and complexity of active materials.
Gradient Bundle Analysis: A Full Topological Approach to Chemical Bonding
Morgenstern, Amanda
2016-01-01
The "chemical bond" is a central concept in molecular sciences, but there is no consensus as to what a bond actually is. Therefore, a variety of bonding models have been developed, each defining the structure of molecules in a different manner with the goal of explaining and predicting chemical properties. This thesis describes the initial development of gradient bundle analysis (GBA), a chemical bonding model that creates a high resolution picture of chemical interactions within the charge density framework. GBA is based on concepts from the quantum theory of atoms in molecules (QTAIM), but uses a more complete picture of the topology and geometry of the electron charge density to understand and predict bonding interactions. Gradient bundles are defined as volumes bounded by zero-flux surfaces (ZFSs) in the gradient of the charge density with well-defined energies. The structure of gradient bundles provides an avenue for detecting the locations of valence electrons, which correspond to reactive regions in a ...
The Analysis of SBWR Critical Power Bundle Using Cobrag Code
Directory of Open Access Journals (Sweden)
Yohannes Sardjono
2013-03-01
Full Text Available The coolant mechanism of SBWR is similar with the Dodewaard Nuclear Power Plant (NPP in the Netherlands that first went critical in 1968. The similarity of both NPP is cooled by natural convection system. These coolant concept is very related with same parameters on fuel bundle design especially fuel bundle length, core pressure drop and core flow rate as well as critical power bundle. The analysis was carried out by using COBRAG computer code. COBRAG computer code is GE Company proprietary. Basically COBRAG computer code is a tool to solve compressible three-dimensional, two fluid, three field equations for two phase flow. The three fields are the vapor field, the continuous liquid field, and the liquid drop field. This code has been applied to analyses model flow and heat transfer within the reactor core. This volume describes the finitevolume equations and the numerical solution methods used to solve these equations. This analysis of same parameters has been done i.e.; inlet sub cooling 20 BTU/lbm and 40 BTU/lbm, 1000 psi pressure and R-factor is 1.038, mass flux are 0.5 Mlb/hr.ft2, 0.75 Mlb/hr.ft2, 1.00 Mlb/hr.ft2 and 1.25 Mlb/hr.ft2. Those conditions based on history operation of some type of the cell fuel bundle line at GE Nuclear Energy. According to the results, it can be concluded that SBWR critical power bundle is 10.5 % less than current BWR critical power bundle with length reduction of 12 ft to 9 ft.
Energy Technology Data Exchange (ETDEWEB)
Raj, M.Naveen; Velusamy, K., E-mail: kvelu@igcar.gov.in; Maity, Ram Kumar
2016-07-15
Highlights: • We simulate flow and temperature fields in FBR fuel bundle with porous blockage. • We perform RANS-based CFD simulation for 217 pin bundle of 7 axial pitch lengths. • Flow reduction in fuel bundle due to porous internal blockage is estimated. • Monitoring bulk sodium outlet temperature does not guarantee blockage detection. • Admissible blockage length to avoid sodium boiling is determined. - Abstract: Thermal hydraulic characteristics of sodium flow in a prototype fuel subassembly with porous internal blockage have been investigated by computational fluid dynamics (CFD) simulations. CFD solutions for a subassembly having 217 pin bundle with seven helical pitch length were obtained by parallel processing. The CFD model has been validated against benchmark blockage experiment reported in literature. Wide parametric ranges for blockage radius, porosity, mean particle diameter and location of blockage have been considered. Critical length of blockage that would result in local sodium boiling as a function of aforementioned blockage parameters has been estimated and the parametric zone posing risk of sodium boiling has been identified. Attention has been paid to coolant mixing and flow and temperature fields downstream of the blockage zone. It is seen that for a prototype subassembly with various sections contributing to pressure loss, the total flow reduction is <2.5% for all blockages that can lead to local sodium boiling. This suggests, that global bulk sodium temperature monitoring at subassembly outlet is unlikely to detect slowly growing blockages. Comparing the sodium flow and temperature fields in unblocked and blocked bundles, it is found that the wake-induced temperature non-uniformity persist even upto 3 helical pitch length, highlighting that the sodium temperature non-uniformity at the bundle exit can serve as an efficient blockage indicator, provided that the cross-section temperature is mapped by a proper instrumentation. The peak
Chern-Simons functional under gauge transformations on flat bundles
Byun, Yanghyun; Kim, Joohee
2017-01-01
We describe the effect of a gauge transformation on the Chern-Simons functional in a thorough and unifying manner. We use the assumptions that the structure group is compact and connected and, in particular, that the principal bundle is flat. The Chern-Simons functional we consider is the one defined by choosing a flat reference connection. The most critical step in arriving at the main result is to show both the existence and the uniqueness of a cohomology class on the adjoint bundle such that it is the class of the so-called Maurer-Cartan 3-form when restricted to each fiber.
BUNDLE ADJUSTMENTS CCD CAMERA CALIBRATION BASED ON COLLINEARITY EQUATION
Institute of Scientific and Technical Information of China (English)
Liu Changying; Yu Zhijing; Che Rensheng; Ye Dong; Huang Qingcheng; Yang Dingning
2004-01-01
The solid template CCD camera calibration method of bundle adjustments based on collinearity equation is presented considering the characteristics of space large-dimension on-line measurement. In the method, a more comprehensive camera model is adopted which is based on the pinhole model extended with distortions corrections. In the process of calibration, calibration precision is improved by imaging at different locations in the whole measurement space, multi-imaging at the same location and bundle adjustments optimization. The calibration experiment proves that the calibration method is able to fulfill calibration requirement of CCD camera applied to vision measurement.
Cellulosic Fibers: Effect of Processing on Fiber Bundle Strength
DEFF Research Database (Denmark)
Thygesen, Anders; Madsen, Bo; Thomsen, Anne Belinda;
2011-01-01
A range of differently processed cellulosic fibers from flax and hemp plants were investigated to study the relation between processing of cellulosic fibers and fiber bundle strength. The studied processing methods are applied for yarn production and include retting, scutching, carding, and cotto......A range of differently processed cellulosic fibers from flax and hemp plants were investigated to study the relation between processing of cellulosic fibers and fiber bundle strength. The studied processing methods are applied for yarn production and include retting, scutching, carding...
Dialytic Separation of Bundled, Functionalized Carbon Nanotubes from Carbonaceous Impurities
Directory of Open Access Journals (Sweden)
J. Justin Mulvey
2014-11-01
Full Text Available Separating functionalized single-wall carbon nanotubes (SWCNTs from functionalized amorphous carbon is challenging, due to their polydispersity and similar physicochemical properties. We describe a single-step, dialytic separation method that takes advantage of the ability of heavily functionalized SWCNTs to bundle in a polar environment while maintaining their solubility. Experiments on functionalized SWCNTs were compared with functionalized, C60 fullerenes (buckyballs to probe the general applicability of the method and further characterize the bundling process. This approach may simultaneously be used to purify a functionalization reaction mixture of unreacted small molecules and of residual solvents, such as dimethylformamide.
Milnor-Wood type inequalities for Higgs bundles
Hartnick, Tobias
2011-01-01
We explain how the generalized Milnor-Wood inequality of Burger and Iozzi for reductive representations of a cocompact complex-hyperbolic lattice into a Hermitian Lie group translates under Simpson's non-abelian Hodge correspondence into an inequality for topological invariants of the corresponding Higgs bundles. In this way, we obtain an inequality that holds for all Hermitian Lie groups, generalizing the Milnor-Wood type inequalities for Higgs bundles that have been proved for the classical Hermitian Lie groups by Bradlow, Garcia-Prada, and Gothen and by Koziarz and Maubon.
Einstein Manifolds, Abelian Instantons, Bundle Reduction, and the Cosmological Constant
Soo, C P
2001-01-01
The anti-self-dual projection of the spin connections of certain four-dimensional Einstein manifolds can be Abelian in nature. These configurations signify bundle reductions. By a theorem of Kobayashi and Nomizu such a process is predicated on the existence of a covariantly constant field. It turns out that even without fundamental Higgs fields and other physical matter, gravitational self-interactions can generate this mechanism if the cosmological constant is non-vanishing. This article identifies the order parameter, and clarifies how these Abelian instanton solutions are associated with a Higgs triplet which causes the bundle reduction from SO(3) gauge group to U(1).
Arthroscopic double-bundle posterior cruciate ligament reconstruction surgical technique.
Fanelli, Gregory C; Beck, John D; Edson, Craig J
2010-06-01
The keys to successful posterior cruciate ligament (PCL) reconstruction are to identify and treat all pathology, use strong graft material, accurately place tunnels in anatomic insertion sites, minimize graft bending, use a mechanical graft tensioning device, use primary and back-up graft fixation, and use the appropriate postoperative rehabilitation program. Adherence to these technical principles results in successful single-bundle and double-bundle arthroscopic transtibial tunnel PCL reconstruction based on stress radiography, arthrometer, knee ligament rating scales, and patient satisfaction measurements.
Capillary Micro-Flow Through a Fiber Bundle(Ⅰ)
Institute of Scientific and Technical Information of China (English)
ZHU Ying-dan; WANG Ji-hui; TAN Hua; GAO Guo-qiang
2004-01-01
The present work considered the capillary micro-flow through a fiber bundle. The resin heights in the fiber bundle as a function of time were used to determine the experimental values of capillary pressure and the permeability by the nonlinear regression fitting method. The fitting curves showed a good agreement with experiments. However, these values of capillary pressure from short- time experiments were much lower than the theoretical results from the Yang-Laplace Equation. More accurate capillary pressure was predicted from the presented long-run experiment.
Dunkl Operators as Covariant Derivatives in a Quantum Principal Bundle
Durdevich, Micho; Sontz, Stephen Bruce
2013-05-01
A quantum principal bundle is constructed for every Coxeter group acting on a finite-dimensional Euclidean space E, and then a connection is also defined on this bundle. The covariant derivatives associated to this connection are the Dunkl operators, originally introduced as part of a program to generalize harmonic analysis in Euclidean spaces. This gives us a new, geometric way of viewing the Dunkl operators. In particular, we present a new proof of the commutativity of these operators among themselves as a consequence of a geometric property, namely, that the connection has curvature zero.
Dunkl Operators as Covariant Derivatives in a Quantum Principal Bundle
Directory of Open Access Journals (Sweden)
Micho Đurđevich
2013-05-01
Full Text Available A quantum principal bundle is constructed for every Coxeter group acting on a finite-dimensional Euclidean space E, and then a connection is also defined on this bundle. The covariant derivatives associated to this connection are the Dunkl operators, originally introduced as part of a program to generalize harmonic analysis in Euclidean spaces. This gives us a new, geometric way of viewing the Dunkl operators. In particular, we present a new proof of the commutativity of these operators among themselves as a consequence of a geometric property, namely, that the connection has curvature zero.
Dunkl Operators as Covariant Derivatives in a Quantum Principal Bundle
evich, Micho Đurđ
2011-01-01
A quantum principal bundle is constructed for every Coxeter group acting on a finite-dimensional Euclidean space E, and then a connection is also defined on this bundle. The covariant derivatives associated to this connection are the Dunkl operators, originally introduced as part of a program to generalize harmonic analysis in Euclidean spaces. This gives us a new, geometric way of viewing the Dunkl operators. In particular, we present a new proof of the commutivity of these operators among themselves as a consequence of a geometric property, namely, that the connection has curvature zero.
Quillen Bundle and Geometric Prequantization of Non-Abelian Vortices on a Riemann Surface
Indian Academy of Sciences (India)
Rukmini Dey; Samir K Paul
2011-02-01
In this paper we prequantize the moduli space of non-abelian vortices. We explicitly calculate the symplectic form arising from 2 metric and we construct a prequantum line bundle whose curvature is proportional to this symplectic form. The prequantum line bundle turns out to be Quillen’s determinant line bundle with a modified Quillen metric. Next, as in the case of abelian vortices, we construct line bundles over the moduli space whose curvatures form a family of symplectic forms which are parametrized by $\\Psi_0$, a section of a certain bundle. The equivalence of these prequantum bundles are discussed.
The Determinant Bundle on the Moduli Space of Stable Triples over a Curve
Indian Academy of Sciences (India)
Indranil Biswas; N Raghavendra
2002-08-01
We construct a holomorphic Hermitian line bundle over the moduli space of stable triples of the form (1, 2, ), where 1 and 2 are holomorphic vector bundles over a fixed compact Riemann surface , and : 2 → 1 is a holomorphic vector bundle homomorphism. The curvature of the Chern connection of this holomorphic Hermitian line bundle is computed. The curvature is shown to coincide with a constant scalar multiple of the natural Kähler form on the moduli space. The construction is based on a result of Quillen on the determinant line bundle over the space of Dolbeault operators on a fixed ∞ Hermitian vector bundle over a compact Riemann surface.
Logging residue bundling at the roadside in mountain operations
Energy Technology Data Exchange (ETDEWEB)
Spinelli, Raffaele; Magagnotti, Natascia (NR IVALSA, Sesto Fiorentino (Italy))
2009-04-15
The recovery of logging residue offers many benefits, and can be effectively performed with several techniques. This study presents the results of four distinct trials conducted on the Italian Alps with a truck-mounted bundler, and compares them with the figures obtained by the Austrian and German colleagues on the other side of the Alps. Average productivity varied between 14 and 22 bundles per productive machine hour (PMH), or between 10 and 15 bundles per scheduled machine hour (SMH). Mass production ranged from 3.1 to 4.3 oven-dry tonnes /SMH. If the machine is used for at least 800 SMH/year bundling costs will range between Euro 7 and 9/MWh, which is within the profitability limit indicated in Nordic studies. Although bundling may represent an additional cost in the slash-to-chip chain, it offers the important benefit of efficient outdoor winter storage, which is crucial in a region where the supply and demand of fuel biomass are often diachronic. The truck-mounted bundler used on the Alps adopts the same mechanism and achieves the same performance of the Nordic forwarder-mounted application. The main difference lies in its superior road mobility, which is crucial when covering scattered landings
Euler-Lagrange Forms and Cohomology Groups on Jet Bundles
Institute of Scientific and Technical Information of China (English)
CHEN Jing-Bo
2005-01-01
@@ Using the language of jet bundles, we generalize the definitions of Euler-Lagrange one-form and the associated cohomology which were introduced by Guo et al. [Commun. Theor. Phys. 37(2002)1]. Continuous and discreteLagrange mechanics and field theory are presented. Higher order Euler-Lagrange cohomology groups are also introduced.
Get ready: Bundled payments are in your future.
2015-09-01
The Centers for Medicare & Medicaid Services' (CMS') mandatory bundled payment pilot project makes clear that the agency intends to reform Medicare reimbursement. Hospitals in 75 geographic areas are required to participate in a five-year pilot project that puts them at risk for the cost of hip and knee replacements from the time of surgery until 90 days after discharge. Already, more than 6,500 providers are participating in the Bundled Payments for Care Improvement project, a voluntary program where participants can choose from 48 clinical episodes and four models. Even if they won't be part of a bundled payments arrangement, case managers need to shift their thinking to prepare for the future of reimbursement by developing close working relationships with post-acute providers, knowing the services and quality delivered by post-acute providers, and being aware of the costs for the entire episode of care. Case managers will not be able to handle all the responsibilities necessary in a bundled payment arrangement if they have large caseloads.
Hair Cells: Bundles, Tuning, Transduction—A Moderated Discussion
Karavitaki, K. Domenica; Ricci, Anthony J.
2011-11-01
A discussion moderated by the authors on the topic "Hair Cells: Bundles, Tuning, Transduction" was held on 17 July 2011 at the 11th International Mechanics of Hearing Workshop in Williamstown, Massachusetts. The paper provides an edited transcript of the session.
AdS 3-manifolds and Higgs bundles
DEFF Research Database (Denmark)
Alessandrini, Daniele; Li, Qiongling
2015-01-01
In this paper we investigate the relationships between closed AdS 3-manifolds and Higgs bundles. We have a new way to construct AdS structures that allows us to see many of their properties explicitly, for example we can recover the very recent formula by Tholozan for the volumes. We also find...
Geometric Description of Fibre Bundle Surface for Birkhoff System
Institute of Scientific and Technical Information of China (English)
CAO Li-Mei; SUN Hua-Fei; ZHANG Zhen-Ning
2009-01-01
A fibre bundle surface for the BirkhofT system is constructed.The metric and the Riemannian connection of the surface are defined and the representation of the Gaussian curvature of this surface is presented.Finally,three examples for the Birkhoff system are given to illustrate our results.
Self-adjointness of the Gaffney Laplacian on Vector Bundles
Energy Technology Data Exchange (ETDEWEB)
Bandara, Lashi, E-mail: lashi.bandara@chalmers.se [Chalmers University of Technology and University of Gothenburg, Mathematical Sciences (Sweden); Milatovic, Ognjen, E-mail: omilatov@unf.edu [University of North Florida, Department of Mathematics and Statistics (United States)
2015-12-15
We study the Gaffney Laplacian on a vector bundle equipped with a compatible metric and connection over a Riemannian manifold that is possibly geodesically incomplete. Under the hypothesis that the Cauchy boundary is polar, we demonstrate the self-adjointness of this Laplacian. Furthermore, we show that negligible boundary is a necessary and sufficient condition for the self-adjointness of this operator.
Moduli of Parabolic Higgs Bundles and Atiyah Algebroids
DEFF Research Database (Denmark)
Logares, Marina; Martens, Johan
2010-01-01
. By considering the case of full flags, we get a Grothendieck–Springer resolution for all other flag types, in particular for the moduli spaces of twisted Higgs bundles, as studied by Markman and Bottacin and used in the recent work of Laumon–Ngô. We discuss the Hitchin system, and demonstrate that all...
Heat transfer from a tube bundle in a bubble column
Energy Technology Data Exchange (ETDEWEB)
Saxena, S.C.; Vadivel, R.
1988-09-01
Heat transfer coefficient for an immersed five tube bundle in a two-phase (air-water) bubble column is measured as a function of air velocity and other relevant parameters. Average and local air holdup are also measured under identical conditions to characterize the system uniquely.
Chest drain care bundle: Improving documentation and safety.
Hutton, Joe; Graham, Selina
2015-01-01
Chest drain insertion is a common advanced procedure with a significant associated risk of pain, distress, and complications. Nationally, audit and recommendations from leading bodies have highlighted a number of safety concerns around chest drain insertion. Audit work has demonstrated poor levels of documentation; particularly around use of premedication, use of ultrasound guidance and consent. This has obvious potential consequences for patient safety and thus is an important target for improvement work. This project quantifies current standards of documentation and aims to improve this through a combination of accessible and easy to read guidelines, education, and the introduction of a chest drain insertion bundle. National best practice standards were identified through review of national guidance. Drain insertion was prospectively analysed over a three month period to establish baseline standards of documentation. This initial work was presented and a bundle and clinical guidelines produced. Chest drain insertion was then reaudited and assessed for improvement. Results demonstrated an improvement in many areas of documentation, pushing local results above the national average. However, only 40% of cases used the new bundle due to a mixture of staff rotation and an unexpectedly high proportion of drains inserted in non targeted areas including the emergency department, theatre, and intensive care. Despite this, the introduction of accessible guidance and bundle has significantly improved chest drain insertion documentation to the benefit of all.
Formation and Dissociation of Sperm Bundles in Monotremes.
Nixon, Brett; Ecroyd, Heath; Dacheux, Jean-Louis; Dacheux, Francoise; Labas, Valerie; Johnston, Steve D; Jones, Russell C
2016-10-01
Because monotremes are the earliest offshoot of the mammalian lineage, the platypus and short-beaked echidna were studied as model animals to assess the origin and biological significance of adaptations considered unique to therian mammals: epididymal sperm maturation and subsequent capacitation. We show that spermatozoa from both species assemble into bundles of approximately 100 cells during passage through the epididymis and that an epididymal protein-secreted protein, acidic, cysteine-rich (osteonectin; SPARC)-is involved in bundle formation. The bundles persisted during incubation in vitro for at least 1 h under conditions that capacitate therian spermatozoa, and then underwent a time-dependent dissociation to release spermatozoa capable of fertilization. Only after this dissociation could the spermatozoa bind to the perivitelline membrane of a hen's egg, display an altered form of motility reminiscent of hyperactivation, and be induced to undergo an acrosome reaction. It is concluded that the development of sperm bundles in the monotreme epididymis mandates that they require a time-dependent process to be capable of fertilizing an ovum. However, because this functional end point was achieved without overt changes in protein tyrosine phosphorylation (a hallmark of capacitation in therians), it is concluded that the process in monotremes is distinctly different from capacitation in therian mammals. © 2016 by the Society for the Study of Reproduction, Inc.
The Roach muscle bundle and umbilical cord coiling
de Laat, Monique W. M.; Nikkels, Peter G. J.; Franx, Arie; Visser, Gerard H. A.
2007-01-01
Objective: To determine if presence of the Roach muscle, a small muscle bundle tying just beside the umbilical artery, contributes to umbilical cord coiling. Methods: 251 umbilical cords were examined. The umbilical coiling index (UCI) was calculated as the number of coils divided by the cord length
Thermal conversion of bundled carbon nanotubes into graphitic ribbons.
Gutiérrez, H R; Kim, U J; Kim, J P; Eklund, P C
2005-11-01
High temperature heat treatment (HTT) of bundled single-walled carbon nanotubes (SWNTs) in vacuum ( approximately 10(-5) Torr) has been found to lead to the formation of two types of graphitic nanoribbons (GNRs), as observed by high-resolution transmission electron microscopy. Purified SWNT bundles were first found to follow two evolutionary steps, as reported previously, that is, tube coalescence (HTT approximately 1400 degrees C) and then massive bond rearrangement (HTT approximately 1600 degrees C), leading to the formation of bundled multiwall nanotubes (MWNTs) with 3-12 shells. At HTT > 1800 degrees C, we find that these MWNTs collapse into multishell GNRs. The first type of GNR we observed is driven by the collapse of diameter-doubled single-wall nanotubes, and their production is terminated at HTT approximately 1600 degrees C when the MWNTs also start to form. We propose that the collapse is driven by van der Waals forces between adjacent tubes in the same bundle. For HTT > 2000 degrees C, the heat-treated material is found to be almost completely in the multishell GNR form.
On $(k,l)$-stable vector bundles over algebraic curves
Mata-Gutiérrez, Osbaldo
2012-01-01
In this paper, we study the $(k,l)$-stable vector bundles over non-singular projective curve $X$ of genus $g\\geq 2,$ its relation with stability and Segre invariants. For rank 2 and 3, we give an explicit description and relation of $(k,l)$-stability and Brill-Noether loci.
Almost Lie structures on an anchored Banach bundle
Cabau, Patrick
2011-01-01
Under appropriate assumptions, we generalize the concept of linear almost Poisson struc- tures, almost Lie algebroids, almost differentials in the framework of Banach anchored bundles and the relation between these objects. We then obtain an adapted formalism for mechanical systems which is illustrated by the evolutionary problem of the "Hilbert snake"
Frame-independent mechanics:geometry on affine bundles
Grabowska, K.; Grabowski, J.; Urbanski, P.
2005-01-01
Main ideas of the differential geometry on affine bundles are presented. Affine counterparts of Lie algebroid and Poisson structures are introduced and discussed. The developed concepts are applied in a frame-independent formulation of the time-dependent and the Newtonian mechanics.
Fission yeast Scp3 potentially maintains microtubule orientation through bundling.
Directory of Open Access Journals (Sweden)
Kanako Ozaki
Full Text Available Microtubules play important roles in organelle transport, the maintenance of cell polarity and chromosome segregation and generally form bundles during these processes. The fission yeast gene scp3+ was identified as a multicopy suppressor of the cps3-81 mutant, which is hypersensitive to isopropyl N-3-chlorophenylcarbamate (CIPC, a poison that induces abnormal multipolar spindle formation in higher eukaryotes. In this study, we investigated the function of Scp3 along with the effect of CIPC in the fission yeast Schizosaccharomyces pombe. Microscopic observation revealed that treatment with CIPC, cps3-81 mutation and scp3+ gene deletion disturbed the orientation of microtubules in interphase cells. Overexpression of scp3+ suppressed the abnormal orientation of microtubules by promoting bundling. Functional analysis suggested that Scp3 functions independently from Ase1, a protein largely required for the bundling of the mitotic spindle. A strain lacking the ase1+ gene was more sensitive to CIPC, with the drug affecting the integrity of the mitotic spindle, indicating that CIPC has a mitotic target that has a role redundant with Ase1. These results suggested that multiple systems are independently involved to ensure microtubule orientation by bundling in fission yeast.
Bohr--Sommerfeld Lagrangians of moduli spaces of Higgs bundles
DEFF Research Database (Denmark)
Biswas, Indranil; Gammelgaard, Niels Leth; Logares, Marina
Let $X$ be a compact connected Riemann surface of genus at least two. Let $M_H(r,d)$ denote the moduli space of semistable Higgs bundles on $X$ of rank $r$ and degree $d$. We prove that the compact complex Bohr-Sommerfeld Lagrangians of $M_H(r,d)$ are precisely the irreducible components of the n...
Multicell slug flow heat transfer analysis of finite LMFBR bundles
Energy Technology Data Exchange (ETDEWEB)
Yeung, M.K.; Wolf, L.
1978-12-01
An analytical two-dimensional, multi-region, multi-cell technique has been developed for the thermal analysis of LMFBR rod bundles. Local temperature fields of various unit cells were obtained for 7, 19, and 37-rod bundles of different geometries and power distributions. The validity of the technique has been verified by its excellent agreement with the THTB calculational result. By comparing the calculated fully-developed circumferential clad temperature distribution with those of the experimental measurements, an axial correction factor has been derived to account for the entrance effect for practical considerations. Moreover, the knowledge of the local temperature field of the rod bundle leads to the determination of the effective mixing lengths L/sub ij/ for adjacent subchannels of various geometries. It was shown that the implementation of the accurately determined L/sub ij/ into COBRA-IIIC calculations has fairly significant effects on intersubchannel mixing. In addition, a scheme has been proposed to couple the 2-D distributed and lumped parameter calculation by COBRA-IIIC such that the entrance effect can be implanted into the distributed parameter analysis. The technique has demonstrated its applicability for a 7-rod bundle and the results of calculation were compared to those of three-dimensional analyses and experimental measurements.
Temperature response of bundle-sheath conductance in maize leaves
Yin, Xinyou; Putten, Van Der Peter E.L.; Struik, Paul C.; Driever, Steven M.
2016-01-01
A small bundle-sheath conductance (g _{bs}) is essential for the C_{4} CO_{2}-concentrating mechanism to suppress photorespiration effectively. To predict the productivity of C_{4} crops accurately under global warming, it is necessary to examine whether and how g
Negotiating over bundles and prices using aggregate knowledge
Somefun, D.J.A.; Klos, T.B.; La Poutré, J.A.
2004-01-01
Combining two or more items and selling them as one good, a practice called bundling, can be a very effective strategy for reducing the costs of producing, marketing, and selling goods. In this paper, we consider a form of multi-issue negotiation where a shop negotiates both the contents and the pri
A note on stochastic calculus in vector bundles
Catuogno, Pedro J; Ruffino, Paulo R
2011-01-01
The aim of these notes is to relate covariant stochastic integration in a vector bundle $E$ (as in Norris \\cite{Norris}) with the usual Stratonovich calculus via the connector $\\K:TE \\rightarrow E$ (cf. e.g. Paterson \\cite{Paterson} or Poor \\cite{Poor}) which carries the connection dependence.
Exposure Control Using Adaptive Multi-Stage Item Bundles.
Luecht, Richard M.
This paper presents a multistage adaptive testing test development paradigm that promises to handle content balancing and other test development needs, psychometric reliability concerns, and item exposure. The bundled multistage adaptive testing (BMAT) framework is a modification of the computer-adaptive sequential testing framework introduced by…
Rigidity of Minimal Submanifolds with Flat Normal Bundle
Indian Academy of Sciences (India)
Hai-Ping Fu
2010-09-01
Let $M^n(n≥ 3)$ be an -dimensional complete immersed $\\frac{n-2}{n}$-superstable minimal submanifold in an $(n+p)$-dimensional Euclidean space $\\mathbb{R}^{n+p}$ with flat normal bundle. We prove that if the second fundamental form of satisfies some decay conditions, then is an affine plane or a catenoid in some Euclidean subspace.
Chordee repair utilizing a novel technique ensuring neurovascular bundle preservation.
Dean, G E; Burno, D K; Zaontz, M R
2000-03-01
Penile chordee, with and without hypospadias, is amenable to surgical correction. The Nesbit technique of dorsal plication of the ventral tunica albuginea is effective in correcting most cases of corporal disproportion. A hazard with this approach is the potential inclusion of the dorsal neurovascular bundle, with resultant erectile and sensory dysfunction. We developed a simple technique using the Freer elevator to isolate the neurovascular bundle prior to plication. This ensures that no injury occurs to the neurovascular bundle during plication. Since 1994, 37 boys with chordee have been repaired using this approach. Their ages at the time of operation ranged from 5 months to 28 years (mean 9 months). Following standard degloving of the penis, an incision through Buck's fascia is made lateral and parallel to the neurovascular bundle at the maximum level of the chordee. A similar incision is carried out on the contralateral side. A 4-mm-wide Freer elevator is positioned under Buck's fascia while hugging the tunica albuginea. The Freer elevator slides across the midline to the contralateral side, separating Buck's fascia and underlying layers from the tunica albuginea. Following isolation of the bundle, each corporal body is plicated by creating a longitudinal incision through the tunica albuginea, which then is closed transversely with a 5-0 polydioxanone suture. Buck's fascia subsequently is closed with an absorbable suture following confirmation of chordee correction. No complications have been encountered during a mean follow-up of 21 months (range 5-51 months). No patients have required reoperation for persistent chordee. We developed a technique that elevates the neurovascular bundle prior to plication, thereby ensuring no injury to this structure. We have successfully used this modified Nesbit technique since 1994 and have had no complications. Utilization of the Freer elevator adds an estimated 5 minutes to chordee correction compared to a standard
A comprehensive comparison on vibration and heat transfer of two elastic heat transfer tube bundles
Institute of Scientific and Technical Information of China (English)
闫柯; 葛培琪; 翟强
2015-01-01
Elastic heat transfer tube bundles are widely used in the field of flow-induced vibration heat transfer enhancement. Two types of mainly used tube bundles, the planar elastic tube bundle and the conical spiral tube bundle were comprehensively compared in the condition of the same shell side diameter. The natural mode characteristics, the effect of fluid−structure interaction, the stress distribution, the comprehensive heat transfer performance and the secondary fluid flow of the two elastic tube bundles were all concluded and compared. The results show that the natural frequency and the critical velocity of vibration buckling of the planar elastic tube bundle are larger than those of the conical spiral tube bundle, while the stress distribution and the comprehensive heat transfer performance of the conical spiral tube bundle are relatively better.
Early Results of Anatomic Double Bundle Anterior Cruciate Ligament Reconstruction
Directory of Open Access Journals (Sweden)
Demet Pepele
2014-03-01
Full Text Available Aim: The goal in anterior cruciate ligament reconstruction (ACLR is to restore the normal anatomic structure and function of the knee. In the significant proportion of patients after the traditional single-bundle ACLR, complaints of instability still continue. Anatomic double bundle ACLR may provide normal kinematics in knees, much closer to the natural anatomy. The aim of this study is to clinically assess the early outcomes of our anatomical double bundle ACLR. Material and Method: In our clinic between June 2009 and March 2010, performed the anatomic double bundle ACLR with autogenous hamstring grafts 20 patients were evaluated prospectively with Cincinnati, IKDC and Lysholm scores and in clinically for muscle strength and with Cybex II dynamometer. Results: The mean follow-up is 17.8 months (13-21 months. Patients%u2019 scores of Cincinnati, IKDC and Lysholm were respectively, preoperative 18.1, 39.3 and 39.8, while the post-op increased to 27.2, 76.3 and 86.3. In their last check, 17 percent of the patients according to IKDC scores (85% A (excellent and B (good group and 3 patients took place as C (adequate group. The power measurements of quadriceps and hamstring muscle groups of patients who underwent surgery showed no significant difference compared with the intact knees. Discussion: Double-bundle ACL reconstruction is a satisfactory method. There is a need comparative, long-term studies in large numbers in order to determine improving clinical outcome, preventing degeneration and restoring the knee biomechanics better.
Infinitesimal moduli of G2 holonomy manifolds with instanton bundles
de la Ossa, Xenia; Larfors, Magdalena; Svanes, Eirik E.
2016-11-01
We describe the infinitesimal moduli space of pairs ( Y, V) where Y is a manifold with G 2 holonomy, and V is a vector bundle on Y with an instanton connection. These structures arise in connection to the moduli space of heterotic string compactifications on compact and non-compact seven dimensional spaces, e.g. domain walls. Employing the canonical G 2 cohomology developed by Reyes-Carrión and Fernández and Ugarte, we show that the moduli space decomposes into the sum of the bundle moduli {H}_{{overset{ěe }{d}}_A}^1(Y,End(V)) plus the moduli of the G 2 structure preserving the instanton condition. The latter piece is contained in {H}_{overset{ěe }{d}θ}^1(Y,TY) , and is given by the kernel of a map overset{ěe }{F} which generalises the concept of the Atiyah map for holomorphic bundles on complex manifolds to the case at hand. In fact, the map overset{ěe }{F} is given in terms of the curvature of the bundle and maps {H}_{overset{ěe }{d}θ}^1(Y,TY) into {H}_{{overset{ěe }{d}}_A}^2(Y,End(V)) , and moreover can be used to define a cohomology on an extension bundle of TY by End( V). We comment further on the resemblance with the holomorphic Atiyah algebroid and connect the story to physics, in particular to heterotic compactifications on ( Y, V) when α' = 0.
78 FR 29139 - Medicare Program; Bundled Payments for Care Improvement Model 1 Open Period
2013-05-17
... participation in Model 1 of the Bundled Payments for Care Improvement initiative. DATES: Model 1 of the Bundled Payments for Care Improvement Deadline: Interested organizations must submit a Model 1 Open Period... regarding Model 1 of the Bundled Payments for Care Improvement initiative. For additional information...
Energy Technology Data Exchange (ETDEWEB)
Cohen, S.I.; Bharati, S.; Glass, J.; Lev, M.
1981-04-01
A 20-year-old man contracted Hodgkin's disease and was treated with mantle radiotherapy. Heart block developed 11 years later. Electrocardiograms revealed predominant atrioventricular (AV) block and occasional AV conduction. Intracardiac electrograms demonstrated that the site of AV block was above the level of the His bundle. A permanent transvenous pacemaker was implanted. Seven months later the patient died of complications from cryptococcal meningitis. Pathological study of the heart revealed marked arteriosclerosis with fibrosis of the epicardium, myocardium, and endocardium. Examination of the conduction system revealed extensive arteriolosclerosis of the sinoatrial node and its approaches. In addition, there was marked fibrosis of the approaches to the AV node, the AV bundle, and both bundle branches. There was no evidence of Hodgkin's disease. This case documents the rare occurrence of AV block due to tissue destruction by radiotherapy. There was a good correlation between block proximal to the His bundle recording site and fibrosis of the approaches to the AV node.
Energy Technology Data Exchange (ETDEWEB)
Cohen, S.I.; Bharati, S.; Glass, J.; Lev, M.
1981-04-01
A 20-year-old man contracted Hodgkin's disease and was treated with mantle radiotherapy. Heart block developed 11 years later. Electrocardiograms revealed predominant atrioventricular (AV) block and occasional AV conduction. Intracardiac electrograms demonstrated that the site of AV block was above the level of the His bundle. A permanent transvenous pacemaker was implanted. Seven months later the patient died of complications from cryptococcal meningitis. Pathological study of the heart revealed marked arteriosclerosis with fibrosis of the epicardium, myocardium, and endocardium. Examination of the conduction system revealed extensive arteriolosclerosis of the sinoatrial node and its approaches. In addition, there was marked fibrosis of the approaches to the AV node, the AV bundle, and both bundle branches. There was no evidence of Hodgkin's disease. This case documents the rare occurrence of AV block due to tissue destruction by radiotherapy. There was a good correlation between block proximal to the His bundle recording site and fibrosis of the approaches to the AV node.
Total Spinal Block after Thoracic Paravertebral Block.
Beyaz, Serbülent Gökhan; Özocak, Hande; Ergönenç, Tolga; Erdem, Ali Fuat; Palabıyık, Onur
2014-02-01
Thoracic paravertebral block (TPVB) can be performed with or without general anaesthesia for various surgical procedures. TPVB is a popular anaesthetic technique due to its low side effect profile and high analgesic potency. We used 20 mL of 0.5% levobupivacaine for a single injection of unilateral TPVB at the T7 level with neurostimulator in a 63 year old patient with co-morbid disease who underwent cholecystectomy. Following the application patient lost consciousness, and was intubated. Haemodynamic instability was normalised with rapid volume replacement and vasopressors. Anaesthetic drugs were stopped at the end of the surgery and muscle relaxant was antagonised. Return of mucle strenght was shown with neuromuscular block monitoring. Approximately three hours after TPVB, spontaneous breathing started and consciousness returned. A total spinal block is a rare and life-threatening complication. A total spinal block is a complication of spinal anaesthesia, and it can also occur after peripheral blocks. Clinical presentation is characterised by hypotension, bradicardia, apnea, and cardiac arrest. An early diagnosis and appropriate treatment is life saving. In this case report, we want to present total spinal block after TPVB.
Delayed hydride cracking properties of the endplate resistance welds of CANDU fuel bundles
Energy Technology Data Exchange (ETDEWEB)
Shek, G.K.; Wasiluk, B.S., E-mail: Gordon.Shek@kinectrics.com [Kinectrics Inc., Toronto, Ontario (Canada); Freire-Canosa, J. [Nuclear Waste Management Organization, Toronto, Ontario (Canada); Lampman, T. [AMEC NSS, Toronto, Ontario (Canada)
2010-07-01
In order to assess the susceptibility of CANDU fuel bundles endplate resistance welds to Delayed Hydride Cracking (DHC) during long term dry storage, the threshold stress intensity factor (KIH) and crack velocity of DHC in endplate welds of three unirradiated fuel bundles were determined. The three bundles tested covered the 28-element and 37-element designs and two Canadian manufacturers. The range of KIH values and DHC velocities obtained from the endplate welds of the three bundles are consistent with previous results obtained from a 37-element bundle produced by one of the manufacturers. (author)
DEFF Research Database (Denmark)
Jönsson, Jeppe
2015-01-01
Block tearing is considered in several codes as a pure block tension or a pure block shear failure mechanism. However in many situations the load acts eccentrically and involves the transfer of a substantial moment in combination with the shear force and perhaps a normal force. A literature study...... yield lines around the block leads to simple interaction formulas similar to other interaction formulas in the codes.......Block tearing is considered in several codes as a pure block tension or a pure block shear failure mechanism. However in many situations the load acts eccentrically and involves the transfer of a substantial moment in combination with the shear force and perhaps a normal force. A literature study...
Catastrophic Failure and Critical Scaling Laws of Fiber Bundle Material
Directory of Open Access Journals (Sweden)
Shengwang Hao
2017-05-01
Full Text Available This paper presents a spring-fiber bundle model used to describe the failure process induced by energy release in heterogeneous materials. The conditions that induce catastrophic failure are determined by geometric conditions and energy equilibrium. It is revealed that the relative rates of deformation of, and damage to the fiber bundle with respect to the boundary controlling displacement ε0 exhibit universal power law behavior near the catastrophic point, with a critical exponent of −1/2. The proportion of the rate of response with respect to acceleration exhibits a linear relationship with increasing displacement in the vicinity of the catastrophic point. This allows for the prediction of catastrophic failure immediately prior to failure by extrapolating the trajectory of this relationship as it asymptotes to zero. Monte Carlo simulations are completed and these two critical scaling laws are confirmed.
Infinitesimal moduli of G2 holonomy manifolds with instanton bundles
de la Ossa, Xenia; Svanes, Eirik Eik
2016-01-01
We describe the infinitesimal moduli space of pairs $(Y, V)$ where $Y$ is a manifold with $G_2$ holonomy, and $V$ is a vector bundle on $Y$ with an instanton connection. These structures arise in connection to the moduli space of heterotic string compactifications on compact and non-compact seven dimensional spaces, e.g. domain walls. Employing the canonical $G_2$ cohomology $H^*_{{\\check{\\rm d}}_E}(Y,E)$ developed by Reyes-Carri\\'on and Fern\\'andez and Ugarte, we show that the moduli space decomposes into the sum of the bundle moduli $H^1_{{\\check{\\rm d}}_A}(Y,{\\rm End}(V))$ plus the moduli of the $G_2$ structure preserving the instanton condition. The latter piece is contained in $H^1_{{\\check{\\rm d}}_\
The special linear version of the projective bundle theorem
Ananyevskiy, Alexey
2012-01-01
A special linear Grassmann variety SGr(k,n) is the complement to the zero section of the determinant of the tautological vector bundle over Gr(k,n). For a representable ring cohomology theory A(-) with a special linear orientation and invertible stable Hopf map \\eta, including Witt groups and MSL[\\eta^{-1}], we have A(SGr(2,2n+1))=A(pt)[e]/(e^{2n}), and A(SGr(2,2n)) is a truncated polynomial algebra in two variables over A(pt). A splitting principle for such theories is established. We use the computations for the special linear Grassmann varieties to calculate A(BSL_n) in terms of the homogeneous power series in certain characteristic classes of the tautological bundle.
Bohr--Sommerfeld Lagrangians of moduli spaces of Higgs bundles
DEFF Research Database (Denmark)
Biswas, Indranil; Gammelgaard, Niels Leth; Logares, Marina
Let $X$ be a compact connected Riemann surface of genus at least two. Let $M_H(r,d)$ denote the moduli space of semistable Higgs bundles on $X$ of rank $r$ and degree $d$. We prove that the compact complex Bohr-Sommerfeld Lagrangians of $M_H(r,d)$ are precisely the irreducible components of the n......Let $X$ be a compact connected Riemann surface of genus at least two. Let $M_H(r,d)$ denote the moduli space of semistable Higgs bundles on $X$ of rank $r$ and degree $d$. We prove that the compact complex Bohr-Sommerfeld Lagrangians of $M_H(r,d)$ are precisely the irreducible components...
Analyses of bundle experiment data using MATRA-h
Energy Technology Data Exchange (ETDEWEB)
Lim, In Cheol; Chea, Hee Taek [Korea Atomic Energy Research Institute, Taejon (Korea)
1998-06-01
When the construction and operation license for HANARO was renewed in 1995, 25% of CHF penalty was imposed. The reason for this was that the validation work related to the CHF design calculation was not enough for the assurance of CHF margin. As a part of the works to recover this CHF penalty, MATRA-h was developed by implementing the new correlations for the heat transfer, CHF prediction, subcooled void to the MATRA-a, which is the modified version of COBRA-IV-I done by KAERI. Using MATRA-h, the subchannel analyses for the bundle experiment data were performed. The comparison of the code predictions with the experimental results, it was found that the code would give the conservative predictions as far as the CHF in the bundle geometry is concerned. (author). 12 refs., 25 figs., 16 tabs.
Giambelli-type formula for subbundles of the tangent bundle
Kazarian, M E
1996-01-01
Let us consider a generic $n$-dimensional subbundle $\\CV$ of the tangent bundle $TM$ on some given manifold $M$. Given $\\CV$ one can define different degeneracy loci $\\Si_{\\bold r}(\\CV),\\;\\bold r=(r_1\\leq r_2\\leq r_3 dimension of the subspace $\\CV^j(x)\\subset TM(x)$ spanned by all length $\\leq j$ commutators of vector fields tangent to $\\CV$ at $x$ is less than or equal to $r_j$. We calculate 'explicitly' the cohomology classes dual to $\\Si_{\\bold r}(\\CV)$ using determinantal formulas due to W.~Fulton and the expression for the Chern classes of the associated bundle of free Lie algebras in terms of the Chern classes of $\\CV$.
Implementing strategic bundles for infection prevention and management.
Kaier, K; Wilson, C; Hulscher, M; Wollersheim, H; Huis, A; Borg, M; Scicluna, E; Lambert, M-L; Palomar, M; Tacconelli, E; De Angelis, G; Schumacher, M; Wolkewitz, M; Kleissle, E-M; Frank, U
2012-04-01
Healthcare-associated infections (HAI) are considered to be the most frequent adverse event in healthcare delivery. Active efforts to curb HAI have increased across Europe thanks to the growing emphasis on patient safety and quality of care. Recently, there has been dramatic success in improving the quality of patient care by focusing on the implementation of a group or "bundle" of evidenced-based preventive practices to achieve a better outcome than when implemented individually. The project entitled IMPLEMENT is designed to spread and test knowledge on how to implement strategic bundles for infection prevention and management in a diverse sample of European hospitals. The general goal of this project is to provide evidence on how to decrease the incidence of HAI and to improve antibiotic use under routine conditions.
Heat transfer in a bundle cooled with supercritical Freon-12
Energy Technology Data Exchange (ETDEWEB)
Peiman, W.; Milner, A.; Pascoe, C.; Patel, H.; Richards, G.; Pioro, I., E-mail: wargha.peiman@mycampus.uoit.ca, E-mail: igor.pioro@uoit.ca [Univ. of Ontario Inst. of Tech., Faculty of Energy Systems and Nuclear Science, Oshawa, Ontario (Canada)
2010-07-01
This paper focuses on analyzing experimental data on Freon-12 at a supercritical pressure of 4.65 MPa. Experiments were conducted at the Institute of Physics and Power Engineering in Russia. The test section consisted of a pressure tube, ceramic inserts, a hexagonal flow tube and a vertical 7-element bundle installed inside the flow tube. The seven elements of the bundle were made of stainless steel and had an outer diameter of 9.5 mm and a heated length of one meter. Bulk-fluid temperature of the coolant at the inlet and the outlet of the test section and the temperature profile of the central heated element were recorded using thermocouples. For comparison, bulk-fluid, and sheath temperature profiles were calculated using various correlations and results were compared with the experimental values. (author)
Through silicon vias filled with planarized carbon nanotube bundles.
Wang, Teng; Jeppson, Kjell; Olofsson, Niklas; Campbell, Eleanor E B; Liu, Johan
2009-12-02
The feasibility of using carbon nanotube (CNT) bundles as the fillers of through silicon vias (TSVs) has been demonstrated. CNT bundles are synthesized directly inside TSVs by thermal chemical vapor deposition (TCVD). The growth of CNTs in vias is found to be highly dependent on the geometric dimensions and arrangement patterns of the vias at atmospheric pressure. The CNT-Si structure is planarized by a combined lapping and polishing process to achieve both a high removal rate and a fine surface finish. Electrical tests of the CNT TSVs have been performed and their electrical resistance was found to be in the few hundred ohms range. The reasons for the high electrical resistance have been discussed and possible methods to decrease the electrical resistance have been proposed.
Pressure effects on single wall carbon nanotube bundles
Energy Technology Data Exchange (ETDEWEB)
Teredesai, P.V. [Indian Inst. of Science, Bangalore (India). Dept. of Physics; Sood, A.K. [Indian Inst. of Science, Bangalore (India). Dept. of Physics; Chemistry and Physics of Materials Unit, Jawaharlal Nehru Center for Advanced Scientific Research, Jakkur Campus, Jakkur (India); Sharma, S.M.; Karmakar, S.; Sikka, S.K. [High Pressure Physics Div., Bhabha Atomic Research Center, Mumbai (India); Govindaraj, A.; Rao, C.N.R. [Chemistry and Physics of Materials Unit, Jawaharlal Nehru Center for Advanced Scientific Research, Jakkur Campus, Jakkur (India)
2001-01-01
We report high pressure Raman studies on single wall carbon nanotube bundles under hydrostatic conditions using two different pressure transmitting media, alcohol mixture and pure water. The radial and tangential modes show a blue shift when SWNT bundle is immersed in the liquids at ambient pressures. The pressure dependence of the radial modes is the same in both liquids. However, the pressure derivatives d{omega}/dP of the tangential modes are slightly higher for the water medium. Raman results are compared with studies under non-hydrostatic conditions and with recent high-pressure X-ray studies. It is seen that the mode frequencies of the recovered sample after pressure cycling from 26 GPa are downshifted by {proportional_to}7-10 cm{sup -1} as compared to the starting sample. (orig.)
Bundle adjustment with raw inertial observations in UAV applications
Cucci, Davide Antonio; Rehak, Martin; Skaloud, Jan
2017-08-01
It is well known that accurate aerial position and attitude control is beneficial for image orientation in airborne photogrammetry. The aerial control is traditionally obtained by Kalman filtering/smoothing inertial and GNSS observations prior to the bundle-adjustment. However, in Micro Aerial Vehicles this process may result in poor attitude determination due to the limited quality of the inertial sensors, large alignment uncertainty and residual correlations between sensor biases and initial attitude. We propose to include the raw inertial observations directly into the bundle-adjustment instead of as position and attitude weighted observations from a separate inertial/GNSS fusion step. The necessary observation models are derived in detail within the context of the so called ;Dynamic Networks;. We examine different real world cases and we show that the proposed approach is superior to the established processing pipeline in challenging scenarios such as mapping in corridors and in areas where the reception of GNSS signals is denied.
An improved partial bundle method for linearly constrained minimax problems
Directory of Open Access Journals (Sweden)
Chunming Tang
2016-02-01
Full Text Available In this paper, we propose an improved partial bundle method for solving linearly constrained minimax problems. In order to reduce the number of component function evaluations, we utilize a partial cutting-planes model to substitute for the traditional one. At each iteration, only one quadratic programming subproblem needs to be solved to obtain a new trial point. An improved descent test criterion is introduced to simplify the algorithm. The method produces a sequence of feasible trial points, and ensures that the objective function is monotonically decreasing on the sequence of stability centers. Global convergence of the algorithm is established. Moreover, we utilize the subgradient aggregation strategy to control the size of the bundle and therefore overcome the difficulty of computation and storage. Finally, some preliminary numerical results show that the proposed method is effective.
Curved Space-Times by Crystallization of Liquid Fiber Bundles
Hélein, Frédéric; Vey, Dimitri
2017-01-01
Motivated by the search for a Hamiltonian formulation of Einstein equations of gravity which depends in a minimal way on choices of coordinates, nor on a choice of gauge, we develop a multisymplectic formulation on the total space of the principal bundle of orthonormal frames on the 4-dimensional space-time. This leads quite naturally to a new theory which takes place on 10-dimensional manifolds. The fields are pairs of ((α ,ω ),π), where (α ,ω ) is a 1-form with coefficients in the Lie algebra of the Poincaré group and π is an 8-form with coefficients in the dual of this Lie algebra. The dynamical equations derive from a simple variational principle and imply that the 10-dimensional manifold looks locally like the total space of a fiber bundle over a 4-dimensional base manifold. Moreover this base manifold inherits a metric and a connection which are solutions of a system of Einstein-Cartan equations.
Frobenius Pull Backs of Vector Bundles in Higher Dimensions
Indian Academy of Sciences (India)
V Trivedi
2012-11-01
We prove that for a smooth projective variety of arbitrary dimension and for a vector bundle over , the Harder–Narasimhan filtration of a Frobenius pull back of is a refinement of the Frobenius pull back of the Harder–Narasimhan filtration of , provided there is a lower bound on the characteristic (in terms of rank of and the slope of the destabilizing sheaf of the cotangent bundle of ). We also recall some examples, due to Raynaud and Monsky, to show that some lower bound on is necessary. We also give a bound on the instability degree of the Frobenius pull back of in terms of the instability degree of and well defined invariants of .
Wu, Jing; Wang, Heng; Guo, Xuan; Chen, Jiong
2016-08-15
The actin bundle is an array of linear actin filaments cross-linked by actin-bundling proteins, but its assembly and dynamics are not as well understood as those of the branched actin network. Here we used the Drosophila bristle as a model system to study actin bundle formation. We found that cofilin, a major actin disassembly factor of the branched actin network, promotes the formation and positioning of actin bundles in the developing bristles. Loss of function of cofilin or AIP1, a cofactor of cofilin, each resulted in increased F-actin levels and severe defects in actin bundle organization, with the defects from cofilin deficiency being more severe. Further analyses revealed that cofilin likely regulates actin bundle formation and positioning by the following means. First, cofilin promotes a large G-actin pool both locally and globally, likely ensuring rapid actin polymerization for bundle initiation and growth. Second, cofilin limits the size of a nonbundled actin-myosin network to regulate the positioning of actin bundles. Third, cofilin prevents incorrect assembly of branched and myosin-associated actin filament into bundles. Together these results demonstrate that the interaction between the dynamic dendritic actin network and the assembling actin bundles is critical for actin bundle formation and needs to be closely regulated.
HYDRODISSECTION FOR PRESERVATION OF NEUROVASCULAR BUNDLE DURING RADICAL PROSTATECTOMY
Directory of Open Access Journals (Sweden)
H. S. Gevorgyan
2016-01-01
Full Text Available Nerve-sparing radical prostatectomy is one of the high-tech operations in urology, and the challenge of the surgeon is not only to remove the prostate tumor, but also to provide a high quality of life. The fact that most questions devoted from patients in a conversation with the surgeon before the operation are devoted to this issue, shows the importance and relevance. At present, the diagnostic methods allow significantly more likely to detect early prostate cancer, making finding and treatment of these patients more affordable and allows to apply this operation.Lately, it seems urgent to explore the possibility of water jet dissection in the field of urology, in particular, for nerve-sparing prostatectomy. Preservation of erectile function depends largely on the quality of separating the neurovascular bundle. Standard use of electrocautery is associated with damage to the neurovascular bundle. When performing operations using water-jet mobilization of prostate the selective dissection of tissue is performed. This avoids injury of neurovascular bundle and further postoperative complications. The use of this technique may allow the surgeon to provide a more accurate mobilization prostate and selectively controlled intersection vessels heading to the prostate from the neurovascular bundle, reduce intraoperative blood loss, maintaining continence, erectile function.This literature review is considered by the experience of using nerve-sparing radical prostatectomy using a water-jet dissector, estimated intraoperative parameters using this method.However, we have the lack of extensive research capabilities of this technique when performing nerve-preserving radical prostatectomy, that does not allow to make a comprehensive presentation on the benefits of this technique and its effects on erectile function and quality of urination, further study of this issue in such a difficult category of patients.
A review on saturated boiling of liquids on tube bundles
Swain, Abhilas; Das, Mihir Kumar
2014-05-01
A review of recent investigation on boiling of saturated liquids over plain and enhanced tube bundles has been carried out taking the earlier review works as reference point. The experimental observations of various geometry and performance parameters studied by researchers are analyzed keeping current demand of industries in design and development of compact, efficient heat exchanging devices. The study shows that tube spacing plays an important role in determination of compactness of the heat exchanger.
Input modelling for subchannel analysis of CANFLEX fuel bundle
Energy Technology Data Exchange (ETDEWEB)
Park, Joo Hwan; Jun, Ji Su; Suk, Ho Chun [Korea Atomic Energy Research Institute, Taejon (Korea)
1998-06-01
This report describs the input modelling for subchannel analysis of CANFLEX fuel bundle using CASS(Candu thermalhydraulic Analysis by Subchannel approacheS) code which has been developed for subchannel analysis of CANDU fuel channel. CASS code can give the different calculation results according to users' input modelling. Hence, the objective of this report provide the background information of input modelling, the accuracy of input data and gives the confidence of calculation results. (author). 11 refs., 3 figs., 4 tabs.
Prostaglandins temporally regulate cytoplasmic actin bundle formation during Drosophila oogenesis
Spracklen, Andrew J.; Kelpsch, Daniel J.; Chen, Xiang; Spracklen, Cassandra N.; Tootle, Tina L.
2014-01-01
Prostaglandins (PGs)—lipid signals produced downstream of cyclooxygenase (COX) enzymes—regulate actin dynamics in cell culture and platelets, but their roles during development are largely unknown. Here we define a new role for Pxt, the Drosophila COX-like enzyme, in regulating the actin cytoskeleton—temporal restriction of actin remodeling during oogenesis. PGs are required for actin filament bundle formation during stage 10B (S10B). In addition, loss of Pxt results in extensive early actin ...
ETA INVARIANTS, DIFFERENTIAL CHARACTERS AND FLAT VECTOR BUNDLES
Institute of Scientific and Technical Information of China (English)
J.M.BISMUT
2005-01-01
The purpose of this paper is to give a refinement of the Atiyah-Singer families index theorem at the level of differential characters. Also a Riemann-Roch-Grothendieck theorem for the direct image of flat vector bundles by proper submersions is proved,with Chern classes with coefficients in C/Q. These results are much related to prior work of Gillet-Soule, Bismut-Lott and Lott.
Double bundle posterior cruciate ligament reconstruction: surgical technique and results.
Fanelli, Gregory C; Beck, John D; Edson, Craig J
2010-12-01
The keys to successful posterior cruciate ligament reconstruction are to identify and treat all pathology, use strong graft material, accurately place tunnels in anatomic insertion sites, minimize graft bending, use a mechanical graft tensioning device, use primary and back-up graft fixation, and use the appropriate postoperative rehabilitation program. Adherence to these technical principles results in successful single and double-bundle arthroscopic transtibial tunnel posterior cruciate ligament reconstruction based upon stress radiography, arthrometer, knee ligament rating scales, and patient satisfaction measurements.
Image processing for cameras with fiber bundle image relay.
Olivas, Stephen J; Arianpour, Ashkan; Stamenov, Igor; Morrison, Rick; Stack, Ron A; Johnson, Adam R; Agurok, Ilya P; Ford, Joseph E
2015-02-10
Some high-performance imaging systems generate a curved focal surface and so are incompatible with focal plane arrays fabricated by conventional silicon processing. One example is a monocentric lens, which forms a wide field-of-view high-resolution spherical image with a radius equal to the focal length. Optical fiber bundles have been used to couple between this focal surface and planar image sensors. However, such fiber-coupled imaging systems suffer from artifacts due to image sampling and incoherent light transfer by the fiber bundle as well as resampling by the focal plane, resulting in a fixed obscuration pattern. Here, we describe digital image processing techniques to improve image quality in a compact 126° field-of-view, 30 megapixel panoramic imager, where a 12 mm focal length F/1.35 lens made of concentric glass surfaces forms a spherical image surface, which is fiber-coupled to six discrete CMOS focal planes. We characterize the locally space-variant system impulse response at various stages: monocentric lens image formation onto the 2.5 μm pitch fiber bundle, image transfer by the fiber bundle, and sensing by a 1.75 μm pitch backside illuminated color focal plane. We demonstrate methods to mitigate moiré artifacts and local obscuration, correct for sphere to plane mapping distortion and vignetting, and stitch together the image data from discrete sensors into a single panorama. We compare processed images from the prototype to those taken with a 10× larger commercial camera with comparable field-of-view and light collection.
The Business of Bundling: Joining Forces on Joint Replacement.
Kaldy, Joanne
2016-03-01
A mandated bundled-payment program for joint replacement is in place in several regions across the country, and practitioners such as pharmacists are still sorting out their roles in this federal initiative. To get involved, pharmacists need to establish connections with area hospitals and physician groups to promote and document their ability to manage medications, reduce and eliminate medication-related problems and rehospitalizations, and work with patients to maximize adherence and improve communication for those undergoing hip and knee replacement.
"Bundle Data" Approach at GES DISC Targeting Natural Hazards
Shie, C. L.; Shen, S.; Kempler, S. J.
2015-12-01
Severe natural phenomena such as hurricane, volcano, blizzard, flood and drought have the potential to cause immeasurable property damages, great socioeconomic impact, and tragic loss of human life. From searching to assessing the "Big", i.e., massive and heterogeneous scientific data (particularly, satellite and model products) in order to investigate those natural hazards, it has, however, become a daunting task for Earth scientists and applications researchers, especially during recent decades. The NASA Goddard Earth Sciences Data and Information Service Center (GES DISC) has served "Big" Earth science data, and the pertinent valuable information and services to the aforementioned users of diverse communities for years. In order to help and guide our users to online readily (i.e., with a minimum effort) acquire their requested data from our enormous resource at GES DISC for studying their targeted hazard/event, we have thus initiated a "Bundle Data" approach in 2014, first targeting the hurricane event/topic. We have recently worked on new topics such as volcano and blizzard. The "bundle data" of a specific hazard/event is basically a sophisticated integrated data package consisting of a series of proper datasets containing a group of relevant ("knowledge-based") data variables readily accessible to users via a system-prearranged table linking those data variables to the proper datasets (URLs). This online approach has been developed by utilizing a few existing data services such as Mirador as search engine; Giovanni for visualization; and OPeNDAP for data access, etc. The online "Data Cookbook" site at GES DISC is the current host for the "bundle data". We are now also planning on developing an "Automated Virtual Collection Framework" that shall eventually accommodate the "bundle data", as well as further improve our management in "Big Data".
Cerebrocerebellar system and Arnold's bundle: A tractographic study: preliminary results
Directory of Open Access Journals (Sweden)
Eliasz Engelhardt
Full Text Available Abstract The cerebellum, traditionally considered a structure involved in balance and movement control, was more recently recognized as important in cognitive, emotional and behavioral functions. These functions appear to be related to the more recent parts of the cerebellum that belong to the cerebrocerebellar system. One of the key segments of this system is the (prefronto-[penduncule]-pontine projection that represents the Arnold's bundle. Diffusion tensor imaging and tractography (DTI-TR has permitted in vivo virtual dissection of white matter tracts, including those of the cerebellar. Objective: To study the fronto-[peduncule]-pontine projection (Arnold's bundle, with DTI-TR. Methods: Ten normal subjects were included (mean age 30 years. Standard acquisitions in three planes were obtained with a 1.5T GE Signa Horizon scanner, complemented with DTI acquisitions. Post-processing and analysis was performed using an ADW 4.3 workstation running Functool 4.5.3 (GE Medical Systems. A single ROI was placed on the medial third of the cerebral peduncle base, considered the site of convergence of the fibers of Arnold's bundle, bilaterally. Results: Twenty tractograms were obtained. All were constituted by a significant number of fibers in correspondence to the frontal lobe, and part of them anterior to the coronal plane at the anterior commissure, which characterizes them as associated to the prefrontal region. Conclusions: For the first time, frontal lobe related projections were systematically revealed with DTI-TR seeded from cerebral peduncle base ROIs. They showed anatomic coherence with Arnold's bundle, which includes the prefrontopontine segment of the cortico-ponto-cerebellar path, one of the components of the cerebrocerebellar system, acknowledged as fundamental for non-motor functions such as cognition, emotion and behavior.
Topological Aharonov-Bohm Effect and Pseudo-Particle Bundles
Payandeh, Farrin
2016-10-01
Exploiting a topological approach, we discuss the outstanding Aharonov-Bohm effect and try to explain it in the context of the principal P(M, U(1)) bundle. We show that this could be done by excluding a specific region from the main manifold which acts as the solenoid around which the effect is observed. Moreover, we discuss the impacts of pseudo-particles in this topological approach.
Bundle Data Approach at GES DISC Targeting Natural Hazards
Shie, Chung-Lin; Shen, Suhung; Kempler, Steven J.
2015-01-01
Severe natural phenomena such as hurricane, volcano, blizzard, flood and drought have the potential to cause immeasurable property damages, great socioeconomic impact, and tragic loss of human life. From searching to assessing the Big, i.e., massive and heterogeneous scientific data (particularly, satellite and model products) in order to investigate those natural hazards, it has, however, become a daunting task for Earth scientists and applications researchers, especially during recent decades. The NASA Goddard Earth Sciences Data and Information Service Center (GES DISC) has served Big Earth science data, and the pertinent valuable information and services to the aforementioned users of diverse communities for years. In order to help and guide our users to online readily (i.e., with a minimum effort) acquire their requested data from our enormous resource at GES DISC for studying their targeted hazard event, we have thus initiated a Bundle Data approach in 2014, first targeting the hurricane event topic. We have recently worked on new topics such as volcano and blizzard. The bundle data of a specific hazard event is basically a sophisticated integrated data package consisting of a series of proper datasets containing a group of relevant (knowledge--based) data variables readily accessible to users via a system-prearranged table linking those data variables to the proper datasets (URLs). This online approach has been developed by utilizing a few existing data services such as Mirador as search engine; Giovanni for visualization; and OPeNDAP for data access, etc. The online Data Cookbook site at GES DISC is the current host for the bundle data. We are now also planning on developing an Automated Virtual Collection Framework that shall eventually accommodate the bundle data, as well as further improve our management in Big Data.
Analysis of Subchannel and Rod Bundle PSBT Experiments with CATHARE 3
Directory of Open Access Journals (Sweden)
M. Valette
2012-01-01
Full Text Available This paper presents the assessment of CATHARE 3 against PWR subchannel and rod bundle tests of the PSBT benchmark. Noticeable measurements were the following: void fraction in single subchannel and rod bundle, multiple liquid temperatures at subchannel exit in rod bundle, and DNB power and location in rod bundle. All these results were obtained both in steady and transient conditions. Void fraction values are satisfactory predicted by CATHARE 3 in single subchannels with the pipe module. More dispersed predictions of void values are obtained in rod bundles with the CATHARE 3 3D module at subchannel scale. Single-phase liquid mixing tests and DNB tests in rod bundle are also analyzed. After calibrating the mixing in liquid single phase with specific tests, DNB tests using void mixing give mitigated results, perhaps linked to inappropriate use of CHF lookup tables in such rod bundles with many spacers.
Bagger-Witten line bundles on moduli spaces of elliptic curves
Gu, W
2016-01-01
In this paper we discuss Bagger-Witten line bundles over moduli spaces of SCFTs. We review how in general they are `fractional' line bundles, not honest line bundles, twisted on triple overlaps. We discuss the special case of moduli spaces of elliptic curves in detail. There, the Bagger-Witten line bundles does not exist as an ordinary line bundle, but rather is necessarily fractional. As a fractional line bundle, it is nontrivial (though torsion) over the uncompactified moduli stack, and its restriction to the interior, excising corners with enhanced stabilizers, is also fractional. We review and compare to results of recent work arguing that well-definedness of the worldsheet metric implies that the Bagger-Witten line bundle is torsion, and give general arguments on the existence of universal structures on moduli spaces of SCFTs, in which superconformal deformation parameters are promoted to nondynamical fields ranging over the SCFT moduli space.
Mass Transport Through Carbon Nanotube-Polystyrene Bundles
Lin, Rongzhou; Tran, Tuan
2016-05-01
Carbon nanotubes have been widely used as test channels to study nanofluidic transport, which has been found to have distinctive properties compared to transport of fluids in macroscopic channels. A long-standing challenge in the study of mass transport through carbon nanotubes (CNTs) is the determination of flow enhancement. Various experimental investigations have been conducted to measure the flow rate through CNTs, mainly based on either vertically aligned CNT membranes or individual CNTs. Here, we proposed an alternative approach that can be used to quantify the mass transport through CNTs. This is a simple method relying on the use of carbon nanotube-polystyrene bundles, which are made of CNTs pulled out from a vertically aligned CNT array and glued together by polystyrene. We experimentally showed by using fluorescent tagging that the composite bundles allowed measureable and selective mass transport through CNTs. This type of composite bundle may be useful in various CNT research areas as they are simple to fabricate, less likely to form macroscopic cracks, and offer a high density of CNT pores while maintaining the aligned morphology of CNTs.
Fabrication of CANFLEX bundle kit for irradiation test in NRU
Energy Technology Data Exchange (ETDEWEB)
Cho, Moon Sung; Kwon, Hyuk Il; Ji, Chul Goo; Chang, Ho Il; Sim, Ki Seob; Suk, Ho Chun
1997-10-01
CANFLEX bundle kit was prepared at KAERI for the fabrication of complete bundle at AECL. Completed bundle will be used for irradiation test in NRU. Provisions in the `Quality Assurance Manual for HWR Fuel Projects,` `Manufacturing Plan` and `Quality Verification, Inspection and Test Plan` were implemented as appropriately for the preparation of CANFLEX kit. A set of CANFLEX kit consist of 43 fuel sheath of two different sizes with spacers, bearing pads and buttons attached, 2 pieces of end plates and 86 pieces of end caps with two different sizes. All the documents utilized as references for the fabrication such as drawings, specifications, operating instructions, QC instructions and supplier`s certificates are specified in this report. Especially, suppliers` certificates and inspection reports for the purchased material as well as KAERI`s inspection report are integrated as attachments to this report. Attached to this report are supplier`s certificates and KAERI inspection reports for the procured materials and KAERI QC inspection reports for tubes, pads, spacers, buttons, end caps, end plates and fuel sheath. (author). 37 refs.
Conservation of helical bundle structure between the exocyst subunits.
Directory of Open Access Journals (Sweden)
Nicole J Croteau
Full Text Available BACKGROUND: The exocyst is a large hetero-octomeric protein complex required for regulating the targeting and fusion of secretory vesicles to the plasma membrane in eukaryotic cells. Although the sequence identity between the eight different exocyst subunits is less than 10%, structures of domains of four of the subunits revealed a similar helical bundle topology. Characterization of several of these subunits has been hindered by lack of soluble protein for biochemical and structural studies. METHODOLOGY/PRINCIPAL FINDINGS: Using advanced hidden Markov models combined with secondary structure predictions, we detect significant sequence similarity between each of the exocyst subunits, indicating that they all contain helical bundle structures. We corroborate these remote homology predictions by identifying and purifying a predicted domain of yeast Sec10p, a previously insoluble exocyst subunit. This domain is soluble and folded with approximately 60% alpha-helicity, in agreement with our predictions, and capable of interacting with several known Sec10p binding partners. CONCLUSIONS/SIGNIFICANCE: Although all eight of the exocyst subunits had been suggested to be composed of similar helical bundles, this has now been validated by our hidden Markov model structure predictions. In addition, these predictions identified protein domains within the exocyst subunits, resulting in creation and characterization of a soluble, folded domain of Sec10p.
Explicit presentations of nonspecial line bundles and secant spaces
Kim, Seonja
2012-01-01
A line bundle L on a smooth curve X is nonspecial if and only if L admits a presentation L=K_X -D +E for some effective divisors D and E>0 on X with gcd (D, E)=0 and h^0 (X, O_X (D))=1. In this work, we define a minimal presentation of L which is minimal with respect to the degree of E among the presentations. If L=K_X -D +E with degE>2 is a minimal, then L is very ample and any q-points of X with q
Real bundle gerbes, orientifolds and twisted KR-homology
Hekmati, Pedram; Szabo, Richard J; Vozzo, Raymond F
2016-01-01
We introduce a notion of Real bundle gerbes on manifolds equipped with an involution. We elucidate their relation to Jandl gerbes and prove that they are classified by their Real Dixmier-Douady class in Grothendieck's equivariant sheaf cohomology. We show that the Grothendieck group of Real bundle gerbe modules is isomorphic to twisted KR-theory for a torsion Real Dixmier-Douady class. Building on the Baum-Douglas model for K-homology and the orientifold construction in string theory, we introduce geometric cycles for twisted KR-homology groups using Real bundle gerbe modules. We prove that this defines a real-oriented generalised homology theory dual to twisted KR-theory for Real closed manifolds, and more generally for Real finite CW-complexes, for any Real Dixmier-Douady class. This is achieved by defining an explicit natural transformation to analytic twisted KR-homology and proving that it is an isomorphism. Our constructions give a new framework for the classification of orientifolds in string theory, p...
An elastic model for bioinspired design of carbon nanotube bundles
Sun, Xiaoyu; Zhang, Zuoqi; Xu, Yuanjie; Zhang, Yongwei
2015-04-01
Collagen fibers provide a good example of making strong micro- or mesoscale fibers from nanoscale tropocollagen molecules through a staggered and cross-linked organization in a bottom-up manner. Mimicking the architectural features of collagen fibers has been shown to be a promising approach to develop carbon nanotube (CNT) fibers of high performance. In the present work, an elastic model is developed to describe the load transfer and failure propagation within the bioinspired CNT bundles, and to establish the relations of the mechanical properties of the bundles with a number of geometrical and physical parameters such as the CNT aspect ratio and longitudinal gap, interface cross-link density, and the functionalization-induced degradation in CNTs, etc. With the model, the stress distributions along the CNT-CNT interface as well as in every individual CNT are well captured, and the failure propagation along the interface and its effects on the mechanical properties of the CNT bundles are predicted. The work may provide useful guidelines for the design of novel CNT fibers in practice.
Institute of Scientific and Technical Information of China (English)
LUO Hao; AO Ying-fang; ZHANG Wei-guang; LIU Sheng-yong; ZHANG Ji-ying; YU Jia-kuo
2012-01-01
Background Several techniques have been described for posterior cruciate ligament(PCL)reconstruction.However,double-bundle PCL reconstruction using the quadruple bone-tunnel technique has been seldom reported.The current study investigated this technique,focusing on the anatomy of the femoral and tibial insertions of the anterolateral(AL)and posteromedial(PM)bundles of the PCL.Methods Twenty-two fresh,healthy adult cadaveric knees were dissected and measured.The PCL was divided into the AL bundle and PM bundle at the insertion footprint.The insertion footprints of the AL and PM bundles,their location,size,and the clock positions were measured and described.Results On the femur,the clock position of the footprint of the AL bundle was 11:21±0:23(left)or 0:39±0:23(right),and the PM bundle was 9:50±0:18(left)or 2:10±0:18(right),with the knee flexed at 90 degrees.The distances from the center of the femoral insertions of the AL and PM bundles to the anterior cartilage margins of the medial femoral condyle were(7.79±1.22)mm and(8.36±1.63)mm,respectively.On the tibia,the vertical distances from the center of the tibial insertions of the AL and PM bundles to the tibial articular surface were(3.25±1.20)mm and(6.91±1.57)mm,respectively.Conclusions These results have led to a better definition of the anatomy of the AL and PM bundle footprint of the PCL.The technique of double-bundle PCL reconstruction using quadruple bone-tunnel is feasible.Application of these data during PCL reconstruction using the quadruple bone-tunnel technique may help optimize knee stability.
BLOCK H-MATRICES AND SPECTRUM OF BLOCK MATRICES
Institute of Scientific and Technical Information of China (English)
黄廷祝; 黎稳
2002-01-01
The block H-matrices are studied by the concept of G-functions, several concepts of block matrices are introduced. Equivalent characters of block H-matrices are obtained. Spectrum localizations claracterized by Gfunctions for block matrices are got.
Block TERM factorization of block matrices
Institute of Scientific and Technical Information of China (English)
SHE Yiyuan; HAO Pengwei
2004-01-01
Reversible integer mapping (or integer transform) is a useful way to realize Iossless coding, and this technique has been used for multi-component image compression in the new international image compression standard JPEG 2000. For any nonsingular linear transform of finite dimension, its integer transform can be implemented by factorizing the transform matrix into 3 triangular elementary reversible matrices (TERMs) or a series of single-row elementary reversible matrices (SERMs). To speed up and parallelize integer transforms, we study block TERM and SERM factorizations in this paper. First, to guarantee flexible scaling manners, the classical determinant (det) is generalized to a matrix function, DET, which is shown to have many important properties analogous to those of det. Then based on DET, a generic block TERM factorization,BLUS, is presented for any nonsingular block matrix. Our conclusions can cover the early optimal point factorizations and provide an efficient way to implement integer transforms for large matrices.
Compactifications of the Heterotic string with unitary bundles
Energy Technology Data Exchange (ETDEWEB)
Weigand, T.
2006-05-23
In this thesis we investigate a large new class of four-dimensional supersymmetric string vacua defined as compactifications of the E{sub 8} x E{sub 8} and the SO(32) heterotic string on smooth Calabi-Yau threefolds with unitary gauge bundles and heterotic five-branes. The first part of the thesis discusses the implementation of this idea into the E{sub 8} x E{sub 8} heterotic string. After specifying a large class of group theoretic embeddings featuring unitary bundles, we analyse the effective four-dimensional N=1 supergravity upon compactification. From the gauge invariant Kaehler potential for the moduli fields we derive a modification of the Fayet-Iliopoulos D-terms arising at one-loop in string perturbation theory. From this we conjecture a one-loop deformation of the Hermitian Yang-Mills equation and introduce the idea of {lambda}-stability as the perturbatively correct stability concept generalising the notion of Mumford stability valid at tree-level. We then proceed to a definition of SO(32) heterotic vacua with unitary gauge bundles in the presence of heterotic five-branes and find agreement of the resulting spectrum with the S-dual framework of Type I/Type IIB orientifolds. A similar analysis of the effective four-dimensional supergravity is performed. Further evidence for the proposed one-loop correction to the stability condition is found by identifying the heterotic corrections as the S-dual of the perturbative part of {pi}-stability as the correct stability concept in Type IIB theory. After reviewing the construction of holomorphic stable vector bundles on elliptically fibered Calabi-Yau manifolds via spectral covers, we provide semi-realistic examples for SO(32) heterotic vacua with Pati-Salam and MSSM-like gauge sectors. We finally discuss the construction of realistic vacua with flipped SU(5) GUT and MSSM gauge group within the E{sub 8} x E{sub 8} framework, based on the embedding of line bundles into both E{sub 8} factors. Some of the appealing
HLM fuel pin bundle experiments in the CIRCE pool facility
Energy Technology Data Exchange (ETDEWEB)
Martelli, Daniele, E-mail: daniele.martelli@ing.unipi.it [University of Pisa, Department of Civil and Industrial Engineering, Pisa (Italy); Forgione, Nicola [University of Pisa, Department of Civil and Industrial Engineering, Pisa (Italy); Di Piazza, Ivan; Tarantino, Mariano [Italian National Agency for New Technologies, Energy and Sustainable Economic Development, C.R. ENEA Brasimone (Italy)
2015-10-15
Highlights: • The experimental results represent the first set of values for LBE pool facility. • Heat transfer is investigated for a 37-pin electrical bundle cooled by LBE. • Experimental data are presented together with a detailed error analysis. • Nu is computed as a function of the Pe and compared with correlations. • Experimental Nu is about 25% lower than Nu derived from correlations. - Abstract: Since Lead-cooled Fast Reactors (LFR) have been conceptualized in the frame of GEN IV International Forum (GIF), great interest has focused on the development and testing of new technologies related to HLM nuclear reactors. In this frame the Integral Circulation Experiment (ICE) test section has been installed into the CIRCE pool facility and suitable experiments have been carried out aiming to fully investigate the heat transfer phenomena in grid spaced fuel pin bundles providing experimental data in support of European fast reactor development. In particular, the fuel pin bundle simulator (FPS) cooled by lead bismuth eutectic (LBE), has been conceived with a thermal power of about 1 MW and a uniform linear power up to 25 kW/m, relevant values for a LFR. It consists of 37 fuel pins (electrically simulated) placed on a hexagonal lattice with a pitch to diameter ratio of 1.8. The FPS was deeply instrumented by several thermocouples. In particular, two sections of the FPS were instrumented in order to evaluate the heat transfer coefficient along the bundle as well as the cladding temperature in different ranks of sub-channels. Nusselt number in the central sub-channel was therefore calculated as a function of the Peclet number and the obtained results were compared to Nusselt numbers obtained from convective heat transfer correlations available in literature on Heavy Liquid Metals (HLM). Results reported in the present work, represent the first set of experimental data concerning fuel pin bundle behaviour in a heavy liquid metal pool, both in forced and
Sadoghi, Patrick; Mueller, Peter E.; Jansson, Volkmar; van Griensven, Martin; Kroepfl, Albert; Fischmeister, Martin F.
2011-01-01
The study hypothesis was that the outcome of semitendinosus gracilis double bundle (STG-DB) anterior cruciate ligament (ACL) reconstruction is advantageous in terms of clinical results and restoration of anterior-posterior and rotational laxity in comparison to bone-patellar tendon-bone single-bundl
Double-bundle depiction of the anterior cruciate ligament at 3 Tesla
Energy Technology Data Exchange (ETDEWEB)
Adriaensen, M.E.A.P.M. [Atrium Medical Center Parkstad, Department of Radiology, Heerlen (Netherlands); Hogan, B. [Sports Surgery Clinic, Department of Radiology, Dublin (Ireland); Al-Bulushi, H.I.J. [Armed Forces Hospital, Department of Radiology, Muscat (Oman); Kavanagh, E.C. [Mater Misericordiae Hospital, Department of Radiology, Dublin (Ireland)
2012-07-15
Magnetic resonance imaging on 3 Tesla (3T MRI) with arthroscopic correlation has proven to adequately identify the anteromedial bundle (AMB) and posterolateral bundle (PLB) in cadaver knees. The purpose of this study was to describe the depiction of ACL bundle anatomy on 3T MRI in daily practice. In a retrospective cohort study, we included 50 consecutive patients who underwent standard 3T MRI of the knee and had an intact ACL. Two musculoskeletal radiologists independently reviewed all scans for depiction of ACL bundle anatomy using standardized forms. Descriptive statistics were used. Twenty-three right knees (46%) and 27 left knees (54%) were included in the study. Mean age of the patients was 35 years (range 12 to 68 years); 37 patients were male (74%). ACL bundle anatomy was best depicted in the axial plane in 44 knees (88%) and in the coronal plane in six knees (12%). Two bundles were seen in 47 knees (94%). The AMB was completely seen in 45 knees (90%). The PLB was completely seen in 40 knees (80%). Both bundles were completely seen in 37 knees (76%). The double-bundle anatomy of the ACL is visualized in 94% of patients on 3T MRI. Because of potentially associated clinical benefits, we advocate to report separately on the anteromedial bundle and posterolateral bundle in case of anterior cruciate ligament injury of the knee. (orig.)
... Blocked Urethral Valves Health Issues Listen Español Text Size Email Print Share Blocked Urethral Valves Page Content Article Body Urine leaves the bladder through a tube called the urethra, which in boys passes through the penis. Rarely, small membranes form across the urethra in ...
Van der Vegt, Wim
2010-01-01
Related Drupal Nodes Block This module exposes a block that uses Latent Semantic Analysis (Lsa) internally to suggest three nodes that are relevant to the node a user is viewing. This module performs three tasks. 1) It periodically indexes a Drupal site and generates a Lsa Term Document Matrix. Inde
... P wave as it normally would. If an electrical signal is blocked before it reaches the ventricles, they won't contract and pump blood to the lungs and the rest of the body. Second-degree heart block is divided into two ...
Van der Vegt, Wim
2010-01-01
Related Drupal Nodes Block This module exposes a block that uses Latent Semantic Analysis (Lsa) internally to suggest three nodes that are relevant to the node a user is viewing. This module performs three tasks. 1) It periodically indexes a Drupal site and generates a Lsa Term Document Matrix. Inde
Extensional bundle waveguide techniques for measuring flow of hot fluids.
Lynnworth, Lawrence C; Liu, Yi; Umina, John A
2005-04-01
A bundle of acoustically slender metal rods, each thin compared to wavelength, tightly packed within a sheath, and welded closed at each end, provides a dispersion-free waveguide assembly that acts as a thermal buffer between a transducer and the hot fluid medium the flow of which is to be measured. Gas and steam flow applications have ranged up to 600 degrees C. Liquid applications have ranged from cryogenic (-160 degrees C) to 500 degrees C and include intermittent two-phase flows. The individual rods comprising the bundle usually are approximately one millimeter in diameter. The sheath, made of a pipe or tube, typically has an outside diameter of 12.7 to about 33 mm and usually is about 300 mm long. Materials for the sheath and bundle are selected to satisfy requirements of compatibility with the fluid as well as for acoustic properties. Corrosion-resistant alloys such as 316SS and titanium are commonly used. The buffers are used with transducers that are metal-encapsulated and certified for use in hazardous areas. They operate at a frequency in the range of 0.1 to 1 MHz. The radiating end of the buffer is usually flat and perpendicular to the buffer's main axis. In some cases the end of the buffer is stepped or angled. Angling the radiating faces at approximately 2 degrees to overcome beam drift at Mach 0.1 recently contributed to solving a high-temperature high-velocity flow measurement problem. The temperature in this situation was 300 degrees C, and the gas molecular weight was about 95, with pressure 0.9 to 1.1 bar.
"Bundle" Practices and Ventilator-Associated Events: Not Enough.
O'Horo, John C; Lan, Haitao; Thongprayoon, Charat; Schenck, Louis; Ahmed, Adil; Dziadzko, Mikhail
2016-12-01
OBJECTIVE Ventilator-associated events (VAEs) are nosocomial events correlated with length of stay, costs, and mortality. Current ventilator bundle practices target the older definition of ventilator-associated pneumonia and have not been systematically evaluated for their impact on VAEs. DESIGN Retrospective cohort study. SETTING Tertiary medical center between January 2012 and August 2014. PARTICIPANTS All adult patients ventilated for at least 24 hours at our institution. INTERVENTIONS We conducted univariate analyses for compliance with each element; we focused on VAEs occurring within a 2-day window of failure to meet any ventilator bundle element. We used Cox proportional hazard models to assess the effect of stress ulcer prophylaxis, deep vein thrombosis (DVT) prophylaxis, oral care, and sedation breaks on VAEs. We adjusted models for gender, age, and Acute Physiology and Chronic Health Evaluation (APACHE) III scores. RESULTS Our cohort comprised 2,660 patients with 16,858 ventilator days and 77 VAEs. Adjusting for APACHE score and gender, only oral care was associated with a reduction in the risk of VAE (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.26-0.77). The DVT prophylaxis and sedation breaks did not show any significant impact on VAEs. Stress ulcer prophylaxis trended toward an increased risk of VAE (HR, 1.59; 95% CI, 1.00-2.56). CONCLUSION Although limited by a low baseline rate of VAEs, existing ventilator bundle practices do not appear to target VAEs well. Oral care is clearly important, but the impact of DVT prophylaxis, sedation breaks, and especially stress ulcer prophylaxis are questionable at best. Infect Control Hosp Epidemiol 2016;1453-1457.
Early Lessons on Bundled Payment at an Academic Medical Center.
Jubelt, Lindsay E; Goldfeld, Keith S; Blecker, Saul B; Chung, Wei-Yi; Bendo, John A; Bosco, Joseph A; Errico, Thomas J; Frempong-Boadu, Anthony K; Iorio, Richard; Slover, James D; Horwitz, Leora I
2017-09-01
Orthopaedic care is shifting to alternative payment models. We examined whether New York University Langone Medical Center achieved savings under the Centers for Medicare and Medicaid Services Bundled Payments for Care Improvement initiative. This study was a difference-in-differences study of Medicare fee-for-service patients hospitalized from April 2011 to June 2012 and October 2013 to December 2014 for lower extremity joint arthroplasty, cardiac valve procedures, or spine surgery (intervention groups), or for congestive heart failure, major bowel procedures, medical peripheral vascular disorders, medical noninfectious orthopaedic care, or stroke (control group). We examined total episode costs and costs by service category. We included 2,940 intervention episodes and 1,474 control episodes. Relative to the trend in the control group, lower extremity joint arthroplasty episodes achieved the greatest savings: adjusted average episode cost during the intervention period decreased by $3,017 (95% confidence interval [CI], -$6,066 to $31). For cardiac procedures, the adjusted average episode cost decreased by $2,999 (95% CI, -$8,103 to $2,105), and for spinal fusion, it increased by $8,291 (95% CI, $2,879 to $13,703). Savings were driven predominantly by shifting postdischarge care from inpatient rehabilitation facilities to home. Spinal fusion index admission costs increased because of changes in surgical technique. Under bundled payment, New York University Langone Medical Center decreased total episode costs in patients undergoing lower extremity joint arthroplasty. For patients undergoing cardiac valve procedures, evidence of savings was not as strong, and for patients undergoing spinal fusion, total episode costs increased. For all three conditions, the proportion of patients referred to inpatient rehabilitation facilities upon discharge decreased. These changes were not associated with an increase in index hospital length of stay or readmission rate
Hydrodynamic behavior of a bare rod bundle. [LMFBR
Energy Technology Data Exchange (ETDEWEB)
Bartzis, J.G.; Todreas, N.E.
1977-06-01
The temperature distribution within the rod bundle of a nuclear reactor is of major importance in nuclear reactor design. However temperature information presupposes knowledge of the hydrodynamic behavior of the coolant which is the most difficult part of the problem due to complexity of the turbulence phenomena. In the present work a 2-equation turbulence model--a strong candidate for analyzing actual three dimensional turbulent flows--has been used to predict fully developed flow of infinite bare rod bundle of various aspect ratios (P/D). The model has been modified to take into account anisotropic effects of eddy viscosity. Secondary flow calculations have been also performed although the model seems to be too rough to predict the secondary flow correctly. Heat transfer calculations have been performed to confirm the importance of anisotropic viscosity in temperature predictions. All numerical calculations for flow and heat have been performed by two computer codes based on the TEACH code. Experimental measurements of the distribution of axial velocity, turbulent axial velocity, turbulent kinetic energy and radial Reynolds stresses were performed in the developing and fully developed regions. A 2-channel Laser Doppler Anemometer working on the Reference mode with forward scattering was used to perform the measurements in a simulated interior subchannel of a triangular rod array with P/D = 1.124. Comparisons between the analytical results and the results of this experiment as well as other experimental data in rod bundle array available in literature are presented. The predictions are in good agreement with the results for the high Reynolds numbers.
Testing the BUNDLE Experiment for Microgravity Disturbance Characterization
Gattis, Christy; Engberg, Bob
2000-01-01
A primary objective of the International Space Station is to provide a premier facility for microgravity research. There are many disturbances on board the Station that can disturb the quality of the microgravity environment, including disturbances caused by both system and payload hardware. Disturbances within experiments themselves can also affect the quality of their own environment. The primary functions of the Bridgman Unidirectional Dendrites in Liquids Experiment (BUNDLE) are to melt, directionally solidify, and perform in-situ quench of metallic alloys, providing data to aid in understanding the effects of the microgravity environment on the characteristics of these processed metals. Quenching of the samples in the BUNDLE furnace is accomplished by rapidly introducing high pressure helium into the furnace chamber. This type of quench will induce sample vibrations which may be large enough to adversely affect sample quality. The primary objective of the test described in this presentation was to determine the acceleration imparted on the BUNDLE sample during helium quench. From this information, the science community can better assess whether this method of quench will allow them to obtain the data they need. Utilizing breadboard hardware, the sample quench sequence was conducted. Data was collected from accelerometers located on the breadboard hardware and inside the sample cartridge. The test data indicated that the maximum acceleration achieved by the sample was 0.325 g, which is much higher than the desired microgravity (10(exp -6) g) environment. However, this acceleration level occurred over a time period of less than 0.1 second. Because this time period is so short, there should be no detrimental effects to dendrite growth. This result was consistent with the observations of the experiment scientists, who are satisfied with the results of previous dendrite growth in this breadboard unit.
Arrighi, Pablo
2010-01-01
We define the block neighborhood of a reversible CA, which is related both to its decomposition into a product of block permutations and to quantum computing. We give a purely combinatorial characterization of the block neighborhood, which helps in two ways. First, it makes the computation of the block neighborhood of a given CA relatively easy. Second, it allows us to derive upper bounds on the block neighborhood: for a single CA as function of the classical and inverse neighborhoods, and for the composition of several CAs. One consequence of that is a characterization of a class of "elementary" CAs that cannot be written as the composition of two simpler parts whose neighborhoods and inverse neighborhoods would be reduced by one half.
Directory of Open Access Journals (Sweden)
JONG-YOUL PARK
2014-12-01
Full Text Available In terms of safety and the efficient management of spent fuel storage, detecting failed fuel is one of the most important tasks in a CANada Deuterium Uranium (CANDU reactor operation. It has been successfully demonstrated that in a CANDU reactor, on-power failed fuel detection and location systems, along with alarm area gamma monitors, can detect and locate defective and suspect fuel bundles before discharging them from the reactor to the spent fuel storage bay. In the reception bay, however, only visual inspection has been used to identify suspect bundles. Gaseous fission product and delayed neutron monitoring systems cannot precisely distinguish failed fuel elements from each fuel bundle. This study reports the use of a sipping system in a CANDU reactor for the integrity assessment of spent fuel bundles. The integrity assessment of spent fuel bundles using this sipping system has shown promise as a nondestructive test for detecting a defective fuel bundle in a CANDU reactor.
BEAM 1.7: development for modelling fuel element and bundle buckling strength
Energy Technology Data Exchange (ETDEWEB)
Cheng, G.; Xu, S.; Xu, Z.; Paul, U.K. [Atomic Energy of Canada, Mississauga, Ontario (Canada)
2010-07-01
This paper describes BEAM, an AECL developed computer program, used to assess mechanical integrity of CANDU fuel bundles. The BEAM code has been developed to satisfy the need for buckling strength analysis of fuel bundles. Buckling refers to the phenomenon where a compressive axial load is large enough that a small lateral load can cause large lateral deflections. The buckling strength refers to the critical compressive axial load at which lateral instability is reached. The buckling strength analysis has practical significance for the design of fuel bundles, where the buckling strength of a fuel element/bundle is assessed so that the conditions leading to bundle jamming in the pressure tube are excluded. This paper presents the development and qualification of the BEAM code, with emphasis on the theoretical background and code implementation of the newly developed fuel element/bundle buckling strength model. (author)
Semistable vector bundles and Tannaka duality from a computational point of view
Kaid, Almar
2011-01-01
We develop a semistability algorithm for vector bundles which are given as a kernel of a surjective morphism between splitting bundles on the projective space over an algebraically closed field K. This class of bundles is a generalization of syzygy bundles. We show how to implement this algorithm in a computer algebra system. Further we give applications, mainly concerning the computation of Tannaka dual groups of stable vector bundles of degree 0 on the projective space and on certain smooth complete intersection curves. We also use our algorithm to close a gap in a recent work of L. Costa, P. Macias Marques and R. M. Miro-Roig regarding the stability of the syzygy bundle of general forms. Finally, we apply our algorithm to provide a computational approach to tight closure. All algorithms are implemented in the computer algebra system CoCoA
Gauge Theories and Fiber Bundles: Definitions, Pictures, and Results
Marsh, Adam
2016-01-01
A pedagogical but concise overview of fiber bundles and their connections is provided, in the context of gauge theories in physics. The emphasis is on defining and visualizing concepts and relationships between them, as well as listing common confusions, alternative notations and jargon, and relevant facts and theorems. Special attention is given to detailed figures and geometric viewpoints, some of which would seem to be novel to the literature. Topics are avoided which are well covered in textbooks, such as historical motivations, proofs and derivations, and tools for practical calculations. The present paper is best read in conjunction with the similar paper on Riemannian geometry cited herein.
A Universal Family of Deformations for the Uniformising Higgs bundle
Dalakov, Peter
2011-01-01
Fix a simple complex Lie group G and a principal sl(2,C) subalgebra of Lie(G). Then the moduli space of semi-stable, topologically trivial G-Higgs bundles on a hyperbolic, spin Riemann surface acquires a marked point. This is the unique C*-fixed point on the Hitchin section. We describe a universal analytic family of deformations which provides holomorphic Darboux coordinates in a neighbourhood of the section. This is a special case of a more general deformation-theoretic construction in the spirit of Kuranishi theory. As a toy example of the latter we consider the tautological family of centralisers over the Kostant slice.
Vector-valued automorphic forms and vector bundles
Saber, Hicham
2013-01-01
For an arbitrary discrete group $\\Gamma$ and an $n$-dimensional complex representation $R$ of $\\Gamma$, we prove the existence of $n$ linearly independent vector-valued automorphic forms for $\\Gamma$ with multiplier $R$. To this end, we realize these automorphic forms as sections of a rank $n$ vector bundle attached to a 1-cocycle with coefficients in the sheaf $\\mbox{GL}(n,{\\mathcal O}_X)$, $X$ being the quotient of the Poincar\\'e half-plane by $\\Gamma$ completed with the cusps of $\\Gamma$.
Principal Bundles whose Restrictions to a Curve are Isomorphic
Indian Academy of Sciences (India)
Sudarshan Rajendra Gurjar
2011-05-01
Let be a normal projective variety defined over an algebraically closed field . Let $|O_X(1)|$ be a very ample invertible sheaf on . Let be an affine algebraic group defined over . Let $E_G$ and $F_G$ be two principal -bundles on . Then there exists an integer $n \\gg 0$ (depending on $E_G$ and $F_G$) such that if the restrictions of $E_G$ and $F_G$ to a curve $C\\in |O_X(n)|$ are isomorphic, then they are isomorphic on all of .
On bundles of rank 3 computing Clifford indices
Lange, H
2012-01-01
Let $C$ be a smooth irreducible projective algebraic curve defined over the complex numbers. The notion of the Clifford index of $C$ was extended a few years ago to semistable bundles of any rank. Recent work has been focussed mainly on the rank-2 Clifford index, although interesting results have also been obtained for the case of rank 3. In this paper we extend this work, obtaining improved lower bounds for the rank-3 Clifford index. This allows the first computations of the rank-3 index in non-trivial cases and examples for which the rank-3 index is greater than the rank-2 index.
Visualization of the medial forebrain bundle using diffusion tensor imaging
Directory of Open Access Journals (Sweden)
Ardian eHana
2015-10-01
Full Text Available Diffusion tensor imaging is a technique that enables physicians the portrayal of white matter tracts in vivo. We used this technique in order to depict the medial forebrain bundle in 15 consecutive patients between 2012 and 2015. Men and women of all ages were included. There were 6 women and 9 men. The mean age was 58,6 years (39-77. Nine patients were candidates for an eventual deep brain stimulation. Eight of them suffered from Parkinson`s disease and one had multiple sclerosis. The remaining 6 patients suffered from different lesions which were situated in the frontal lobe. These were 2 metastasis, 2 meningiomas, 1 cerebral bleeding and 1 glioblastoma. We used a 3DT1-sequence for the navigation. Furthermore T2- and DTI- sequences were performed. The FOV was 200 x 200 mm², slice thickness 2 mm, and an acquisition matrix of 96 x 96 yielding nearly isotropic voxels of 2 x 2 x 2 mm. 3-Tesla-MRI was carried out strictly axial using 32 gradient directions and one b0-image. We used Echo-Planar-Imaging (EPI and ASSET parallel imaging with an acceleration factor of 2. b-value was 800 s/mm². The maximal angle was 50°. Additional scanning time was less than 9 minutes. We were able to visualize the medial forebrain bundle in 12 of our patients bilaterally and in the remaining 3 patients we depicted the medial forebrain bundle on one side. It was the contralateral side of the lesion. These were 2 meningiomas and one metastasis. Portrayal of the medial forebrain bundle is possible for everyday routine for neurosurgical interventions. As part of the reward circuitry it might be of substantial importance for neurosurgeons during deep brain stimulation in patients with psychiatric disorders. Furthermore it might explain at a certain extent character changes in patients with lesions in the frontal lobe. Surgery in this part of the brain should always take the preservation of this white matter tract into account.
Bundle adjustment for data processing of theodolite industrial surveying system
Institute of Scientific and Technical Information of China (English)
邹峥嵘; 丁晓利; 曾卓乔; 何凭宗
2001-01-01
The photogrammetric bundle adjustment was used in data processing of electronic theodolite industrial surveying system by converting angular observations into virtual photo coordinates. The developed algorithm has ability of precision estimation and data-snooping, do not need initial values of exterior orientation elements and object point coordinates. The form of control condition for the system is quite flexible. Neither centering nor leveling is the theodolite needed and the lay-out of theodolite position is flexible when the system is used for precise survey. Experiments carried out in test field verify the validity of the data processing method.
Khurana, Ekta; Devane, Russell H; Dal Peraro, Matteo; Klein, Michael L
2011-02-01
The M2 protein of influenza A virus performs the crucial function of transporting protons to the interior of virions enclosed in the endosome. Adamantane drugs, amantadine (AMN) and rimantidine (RMN), block the proton conduction in some strains, and have been used for the treatment and prophylaxis of influenza A infections. The structures of the transmembrane (TM) region of M2 that have been solved in micelles using NMR (residues 23-60) (Schnell and Chou, 2008) and by X-ray crystallography (residues 22-46) (Stouffer et al., 2008) suggest different drug binding sites: external and internal for RMN and AMN, respectively. We have used molecular dynamics (MD) simulations to investigate the nature of the binding site and binding mode of adamantane drugs on the membrane-bound tetrameric M2-TM peptide bundles using as initial conformations the low-pH AMN-bound crystal structure, a high-pH model derived from the drug-free crystal structure, and the high-pH NMR structure. The MD simulations indicate that under both low- and high-pH conditions, AMN is stable inside the tetrameric bundle, spanning the region between residues Val27 to Gly34. At low pH the polar group of AMN is oriented toward the His37 gate, while under high-pH conditions its orientation exhibits large fluctuations. The present MD simulations also suggest that AMN and RMN molecules do not show strong affinity to the external binding sites.
Shu, Jessica Y.; Xu, Ting
2016-01-01
Coiled-coil peptide–polymer conjugates are an emerging class of biomaterials. Fundamental understanding of the coiled-coil oligomeric state and assembly process of these hybrid building blocks is necessary to exert control over their assembly into well-defined structures. Here, we studied the effect of peptide structure and PEGylation on the self-assembly process and oligomeric state of a Langmuir monolayer of amphiphilic coiled-coil peptide–polymer conjugates using X-ray reflectivity (XR) and grazing-incidence X-ray diffraction (GIXD). Our results show that the oligomeric state of PEGylated amphiphiles based on 3-helix bundle-forming peptide is surface pressure dependent, a mixture of dimers and trimers was formed at intermediate surface pressure but transitions into trimers completely upon increasing surface pressure. Moreover, the interhelical distance within the coiled-coil bundle of 3-helix peptide-PEG conjugate amphiphiles was not perturbed under high surface pressure. Present studies provide valuable insights into the self-assembly process of hybrid peptide–polymer conjugates and guidance to develop biomaterials with controlled multivalency of ligand presentation. PMID:27784156
Natural Diagonal Riemannian Almost Product and Para-Hermitian Cotangent Bundles
Druta-Romaniuc, Simona-Luiza
2011-01-01
We obtain the natural diagonal almost product and locally product structures on the total space of the cotangent bundle of a Riemannian manifold. We find the Riemannian almost product (locally product) and the (almost) para-Hermitian cotangent bundles of natural diagonal lift type. We prove the characterization theorem for the natural diagonal (almost) para-K\\"ahlerian structures on the total spaces of the cotangent bundle.
The spectral density function for the Laplacian on high tensor powers of a line bundle
2001-01-01
For a symplectic manifold with quantizing line bundle, a choice of almost complex structure determines a Laplacian acting on tensor powers of the bundle. For high tensor powers Guillemin-Uribe showed that there is a well-defined cluster of low-lying eigenvalues, whose distribution is described by a spectral density function. We give an explicit computation of the spectral density function, by constructing certain quasimodes on the associated principle bundle.
Hussein, Mohsen; van Eck, Carola F; Cretnik, Andrej; Dinevski, Dejan; Fu, Freddie H
2012-03-01
Three different techniques of anterior cruciate ligament (ACL) reconstruction--conventional (transtibial) single bundle (CSB), anatomic single bundle (ASB), and anatomic double bundle (ADB)--have been described. To determine if double-bundle reconstruction is needed to restore rotational stability or if anatomic placement of a single bundle can yield similar results. Randomized controlled trial; Level of evidence, 1. From December 2005 to December 2007, 320 patients were prospectively randomized into 3 groups: ADB, ASB, and CSB reconstruction. The average follow-up was 51.15 months (range, 39-63 months). At the final follow-up, 281 patients were available. In all groups, hamstring tendons were used with suspensory fixation on the femoral side and bioabsorbable interference screw fixation on the tibial side. The outcomes were evaluated by an independent blinded observer using the Lysholm score and subjective International Knee Documentation Committee (IKDC) form. The KT-1000 arthrometer was used to evaluate anteroposterior stability, and the pivot-shift test was used to determine rotational stability. Anatomic single-bundle reconstruction resulted in better anteroposterior and rotational stability than CSB reconstruction (average side-to-side difference for anterior tibial translation was 1.6 mm in the ASB group vs 2.0 mm in the CSB group; P = .002). Negative pivot shift was 66.7% vs 41.7% (P = .003). In other parameters, the differences between groups were not statistically significant. The results of the ADB group were also superior to the ASB group for anteroposterior and rotational stability (average side-to-side difference for anterior tibial translation was 1.2 mm in the ADB group vs 1.6 mm in the ASB group; P = .002). Negative pivot shift was 93.1% vs 66.7%, respectively (P ADB groups, respectively. The difference was significant only when we compared ADB and CSB (P = .025). Subjective IKDC scores were 90.2, 90.6, and 92.1 in the CSB, ASB, and ADB groups
Overview of methods to increase dryout power in CANDU fuel bundles
Energy Technology Data Exchange (ETDEWEB)
Groeneveld, D.C., E-mail: degroeneveld@gmail.com [Chalk River Laboratories, AECL, Chalk River (Canada); University of Ottawa, Department of Mechanical Engineering, Ottawa (Canada); Leung, L.K.H. [Chalk River Laboratories, AECL, Chalk River (Canada); Park, J.H. [Korean Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2015-06-15
Highlights: • Small changes in bundle geometry can have noticeable effects on the bundle CHF. • Rod spacing devices can results in increases of over 200% in CHF. • CHF enhancement decays exponentially downstream from spacers. • CHF-enhancing bundle appendages also increase the post-CHF heat transfer. - Abstract: In CANDU reactors some degradation in the CCP (critical channel power, or power corresponding to the first occurrence of CHF in any fuel channel) will occur with time because of ageing effects such as pressure-tube diametral creep, increase in reactor inlet-header temperature, increased hydraulic resistance of feeders. To compensate for the ageing effects, various options for recovering the loss in CCP are described in this paper. They include: (i) increasing the bundle heated perimeter, (ii) optimizing the bundle configuration, (iii) optimizing core flow and flux distribution, (iv) reducing the bundle hydraulic resistance, (v) use of CHF-enhancing bundle appendages, (vi) more precise experimentation, and (vii) redefining CHF. The increase in CHF power has been quantified based on experiments on full-scale bundles and subchannel code predictions. The application of several of these CHF enhancement principles has been used in the development of the 43-rod CANFLEX bundle.
Film condensation of R-113 on staggered bundles of horizontal finned tubes
Energy Technology Data Exchange (ETDEWEB)
Honda, H. (Kyushu Univ., Fukuoka (Japan)); Uchima, B. (Kagawa Technical Coll., Marugame (Japan)); Nozu, S.; Torigoe, E.; Imai, S. (Okayama Univ., Tsushima (Japan))
1992-05-01
Film condensation of R-113 on staggered bundles of horizontal finned tubes with vertical vapor downflow was experimentally investigated. Two tubes with flat-sided annular fins and four tubes with three-dimensional fins were tested. The condensate flow and heat transfer characteristics were compared with the previous results for in-line bundles of the same test tubes and a staggered bundle of smooth tubes. The decrease in heat transfer characteristics were compared with the previous results for in-line bundles of the same test tubes and a staggered bundle of smooth tubes. The decrease in heat transfer due to condensate inundation was most significant for the in-line bundles of the three-dimensional fin tubes, whereas the decrease was very slow for both the staggered and in-line bundles of the flat-sided fin tubes. The predictions of the previous theoretical model for a bundle of flat-sided fin tubes agreed fairly well with the measured data at a low vapor velocity. The highest heat transfer performance was provided by the staggered bundle of flat-sided fin tubes with fin dimensions close to the theoretically determined optimum values.
Padilla-Gamiño, J. L.; Weatherby, T. M.; Waller, R. G.; Gates, R. D.
2011-06-01
The majority of scleractinian corals are hermaphrodites that broadcast spawn their gametes separately or packaged as egg-sperm bundles during spawning events that are timed to the lunar cycle. The egg-sperm bundle is an efficient way of transporting gametes to the ocean surface where fertilization takes place, while minimizing sperm dilution and maximizing the opportunity for gamete encounters during a spawning event. To date, there are few studies that focus on the formation and structure of egg-sperm bundle. This study explores formation, ultrastructure, and longevity of the egg-sperm bundle in Montipora capitata, a major reef building coral in Hawai`i. Our results show that the egg-sperm bundle is formed by a mucus layer secreted by the oocytes. The sperm package is located at the center of each bundle, possibly reflecting the development of male and female gametes in different mesenteries. Once the egg-sperm bundle has reached the ocean surface, it breaks open within 10-35 min, depending on the environmental conditions (i.e., wind, water turbulence). Although the bundle has an ephemeral life span, the formation of an egg-sperm bundle is a fundamental part of the reproductive process that could be strongly influenced by climate change and deterioration of water quality (due to anthropogenic effects) and thus requires further investigation.
Designing variable height carbon nanotube bundle for enhanced electron field emission
Khaneja, Mamta; Ghosh, Santanu; Chaudhury, P. K.; Vankar, V. D.; Kumar, Vikram
2015-05-01
A variable height model has been implemented in order to improve the emission performance from a nanotube bundle. A Gaussian distribution of nanotube heights has been considered. This resulted in a nearly uniform electric field distribution across all the nanotubes and consequently an enhanced emission current in comparison to a nanotube bundle with all the nanotubes having the same height. Simulation results from linear as well as area nanotube bundles are reported. The analysis helped in providing a better understanding of the previously reported experimental results on enhanced field emission from plasma treated nanotube bundles having CNTs of variable heights.
Geometry of moduli stacks of (k , l) -stable vector bundles over algebraic curves
Mata-Gutiérrez, O.; Neumann, Frank
2017-01-01
We study the geometry of the moduli stack of vector bundles of fixed rank and degree over an algebraic curve by introducing a filtration made of open substacks build from (k , l) -stable vector bundles. The concept of (k , l) -stability was introduced by Narasimhan and Ramanan to study the geometry of the coarse moduli space of stable bundles. We will exhibit the stacky picture and analyse the geometric and cohomological properties of the moduli stacks of (k , l) -stable vector bundles. For particular pairs (k , l) of integers we also show that these moduli stacks admit coarse moduli spaces and we discuss their interplay.
Heat Transfer Modeling of Staggered Bundle with Round Tubes Screened by Mesh
Directory of Open Access Journals (Sweden)
Dymo B.V.
2016-04-01
Full Text Available The article presents the results of CFD modeling of heat transfer and aerodynamic drag for the first three rows of cross-flowed staggered bundle consisting of round tubes screened by wire mesh. Geometric model of this bundle was developed. Selection of optimal parameters of the bundle finite element model realizes on the base of transition shear stress transport model. Two separate geometric models for even and odd rows of bundle have been elaborated for the scope of computational resources optimization. The results of numerical modeling of heat transfer for the first three rows of the bundle were approximated with the criteria dependences. It has been established that heat transfer stabilization occurs from the second row of the bundle. Stabilized heat transfer is 15 % higher than that for the first row of the bundle and 1.2 … 1.7 times as large in comparison with equivalent bare-tube bundle in a range of Reynolds number from 5000 to 35000. Aerodynamic drag data for the first three rows of the bundle have been obtained.
Sperm competition promotes diversity of sperm bundles in Ohomopterus ground beetles
Takami, Yasuoki; Sota, Teiji
2007-07-01
Diversification of sperm morphology has been investigated in the context of sperm competition, but the adaptive significance of sperm bundles is still unclear. In analyzing 10 taxa of the genus Carabus subgenus Ohomopterus and one related Carabus ground beetles, we found that dimorphic sperm bundles occurred in most species with varied degrees of bimodality, whereas sperm were generally monomorphic. Comparative analyses with phylogenetically independent contrasts revealed that the sizes of large and small sperm bundles evolved more rapidly than, and were not correlated with, the length of sperm, suggesting more intense selection on sperm bundle sizes and their independent responses to different evolutionary forces. The size of large sperm bundles was positively correlated with male genital morphology (pertinent to displacement of rival spermatophores) and postcopulatory guarding duration as well as male body length, suggesting that larger sperm bundles have been favored when the risk of spermatophore displacement is high. Larger sperm bundles may be advantageous because of their ability to migrate more rapidly into the spermatheca. In contrast, no clear association was detected between the small sperm bundle size and mating traits despite its rapid diversification. The present study provides the first record of heteromorphic sperm bundles, the diversity of which may be promoted by sperm competition.
Numerical model for thermal and mechanical behaviour of a CANDU 37-element bundle
Energy Technology Data Exchange (ETDEWEB)
Jiang, L.; MacKay, K. [Martec Limited, Halifax, Nova Scotia (Canada); Gibb, R. [Canadian Nuclear Safety Commission (CNSC), Ottawa, Ontario (Canada)
2010-07-01
Prediction of transient fuel bundle deformations is important for assessing the integrity of fuel and the surrounding structural components under different operating conditions including accidents. For numerical simulation of the interactions between fuel bundle and pressure tube, a reliable numerical bundle model is required to predict thermal and mechanical behaviour of the fuel bundle assembly under different thermal loading conditions. To ensure realistic representations of the bundle behaviour, this model must include all of the important thermal and mechanical features of the fuel bundle, such as temperature-dependent material properties, thermal viscoplastic deformation in sheath, fuel-to-sheath interactions, endplate constraints and contacts between fuel elements. In this paper, we present a finite element based numerical model for predicting macroscopic transient thermal-mechanical behaviour of a complete 37-element CANDU nuclear fuel bundle under accident conditions and demonstrate its potential for being used to investigate fuel bundle to pressure tube interaction in future nuclear safety analyses. This bundle model has been validated against available experimental and numerical solutions and applied to various simulations involving steady-state and transient loading conditions. (author)
Kerr, I. D.; Sankararamakrishnan, R; Smart, O.S.; Sansom, M S
1994-01-01
A parallel bundle of transmembrane (TM) alpha-helices surrounding a central pore is present in several classes of ion channel, including the nicotinic acetylcholine receptor (nAChR). We have modeled bundles of hydrophobic and of amphipathic helices using simulated annealing via restrained molecular dynamics. Bundles of Ala20 helices, with N = 4, 5, or 6 helices/bundle were generated. For all three N values the helices formed left-handed coiled coils, with pitches ranging from 160 A (N = 4) to...
Significance of the resting angles of hair-cell bundles for Hopf bifurcation criticality
Kim, Kyung-Joong; Ahn, Kang-Hun
2016-08-01
We investigate the significance of the inclined angle of a hair bundle at equilibrium. We find that, while the angle gives a geometrical conversion factor between the bundle deflection and the ion channel displacement, it also controls the dynamics of the bundle. We show that a Hopf bifurcation, which enhances sensitivity, can be driven by the geometrical factor. However, existing experimental data indicate that mammalian auditory hair-cell bundles are located far away from the Hopf bifurcation point, suggesting that the high sensitivity of mammalian hearing might come from other mechanisms.
Institute of Scientific and Technical Information of China (English)
Kang, Liping; Jiang, Yishu; Tang, Xiuhua; Yang, Mingyang; Liu, Zonghuai
2012-01-01
One-dimensional manganese oxide nanobelt bundles with birnessite-type structure have been synthesized by a hydrothermal process in a NaOH solution employing K-type layered manganese oxide as a precursor. The obtained manganese oxide nanobelt bundles exhibit excellent discharge properties and cycle stability. The initial capacity is 376 mAh-g-1 and the reversible capacity of 243 mAhog-1 is maintained after the 50th cycle at a current density of 20 mA·g-t. Meanwhile, the manganese oxide nanobelt bundles show an excellent cycle performance even if at relative high current density.
Motor-free actin bundle contractility driven by molecular crowding
Schnauß, Jörg; Schuldt, Carsten; Schmidt, B U Sebastian; Glaser, Martin; Strehle, Dan; Heussinger, Claus; Käs, Josef A
2015-01-01
Modeling approaches of suspended, rod-like particles and recent experimental data have shown that depletion forces display different signatures depending on the orientation of these particles. It has been shown that axial attraction of two rods yields contractile forces of 0.1pN that are independent of the relative axial shift of the two rods. Here, we measured depletion-caused interactions of actin bundles extending the phase space of single pairs of rods to a multi-particle system. In contrast to a filament pair, we found forces up to 3pN . Upon bundle relaxation forces decayed exponentially with a mean decay time of 3.4s . These different dynamics are explained within the frame of a mathematical model by taking pairwise interactions to a multi-filament scale. The macromolecular content employed for our experiments is well below the crowding of cells. Thus, we propose that arising forces can contribute to biological force generation without the need to convert chemical energy into mechanical work.
Hair cell bundles: flexoelectric motors of the inner ear.
Directory of Open Access Journals (Sweden)
Kathryn D Breneman
Full Text Available Microvilli (stereocilia projecting from the apex of hair cells in the inner ear are actively motile structures that feed energy into the vibration of the inner ear and enhance sensitivity to sound. The biophysical mechanism underlying the hair bundle motor is unknown. In this study, we examined a membrane flexoelectric origin for active movements in stereocilia and conclude that it is likely to be an important contributor to mechanical power output by hair bundles. We formulated a realistic biophysical model of stereocilia incorporating stereocilia dimensions, the known flexoelectric coefficient of lipid membranes, mechanical compliance, and fluid drag. Electrical power enters the stereocilia through displacement sensitive ion channels and, due to the small diameter of stereocilia, is converted to useful mechanical power output by flexoelectricity. This motor augments molecular motors associated with the mechanosensitive apparatus itself that have been described previously. The model reveals stereocilia to be highly efficient and fast flexoelectric motors that capture the energy in the extracellular electro-chemical potential of the inner ear to generate mechanical power output. The power analysis provides an explanation for the correlation between stereocilia height and the tonotopic organization of hearing organs. Further, results suggest that flexoelectricity may be essential to the exquisite sensitivity and frequency selectivity of non-mammalian hearing organs at high auditory frequencies, and may contribute to the "cochlear amplifier" in mammals.
Resolving bundled microtubules using anti-tubulin nanobodies.
Mikhaylova, Marina; Cloin, Bas M C; Finan, Kieran; van den Berg, Robert; Teeuw, Jalmar; Kijanka, Marta M; Sokolowski, Mikolaj; Katrukha, Eugene A; Maidorn, Manuel; Opazo, Felipe; Moutel, Sandrine; Vantard, Marylin; Perez, Frank; van Bergen en Henegouwen, Paul M P; Hoogenraad, Casper C; Ewers, Helge; Kapitein, Lukas C
2015-08-11
Microtubules are hollow biopolymers of 25-nm diameter and are key constituents of the cytoskeleton. In neurons, microtubules are organized differently between axons and dendrites, but their precise organization in different compartments is not completely understood. Super-resolution microscopy techniques can detect specific structures at an increased resolution, but the narrow spacing between neuronal microtubules poses challenges because most existing labelling strategies increase the effective microtubule diameter by 20-40 nm and will thereby blend neighbouring microtubules into one structure. Here we develop single-chain antibody fragments (nanobodies) against tubulin to achieve super-resolution imaging of microtubules with a decreased apparent diameter. To test the resolving power of these novel probes, we generate microtubule bundles with a known spacing of 50-70 nm and successfully resolve individual microtubules. Individual bundled microtubules can also be resolved in different mammalian cells, including hippocampal neurons, allowing novel insights into fundamental mechanisms of microtubule organization in cell- and neurobiology.
Prostaglandins temporally regulate cytoplasmic actin bundle formation during Drosophila oogenesis.
Spracklen, Andrew J; Kelpsch, Daniel J; Chen, Xiang; Spracklen, Cassandra N; Tootle, Tina L
2014-02-01
Prostaglandins (PGs)--lipid signals produced downstream of cyclooxygenase (COX) enzymes--regulate actin dynamics in cell culture and platelets, but their roles during development are largely unknown. Here we define a new role for Pxt, the Drosophila COX-like enzyme, in regulating the actin cytoskeleton--temporal restriction of actin remodeling during oogenesis. PGs are required for actin filament bundle formation during stage 10B (S10B). In addition, loss of Pxt results in extensive early actin remodeling, including actin filaments and aggregates, within the posterior nurse cells of S9 follicles; wild-type follicles exhibit similar structures at a low frequency. Hu li tai shao (Hts-RC) and Villin (Quail), an actin bundler, localize to all early actin structures, whereas Enabled (Ena), an actin elongation factor, preferentially localizes to those in pxt mutants. Reduced Ena levels strongly suppress early actin remodeling in pxt mutants. Furthermore, loss of Pxt results in reduced Ena localization to the sites of bundle formation during S10B. Together these data lead to a model in which PGs temporally regulate actin remodeling during Drosophila oogenesis by controlling Ena localization/activity, such that in S9, PG signaling inhibits, whereas at S10B, it promotes Ena-dependent actin remodeling.
Synergetic driving concepts for bundled miniature ultrasonic linear motors.
Mracek, Maik; Hemsel, Tobias
2006-12-22
Rotary ultrasonic motors have found broad industrial application in camera lens drives and other systems. Linear ultrasonic motors in contrast have only found limited applications. The main reason for the limited range of application of these very attractive devices seems to be their small force and power range. Attempts to build linear ultrasonic motors for high forces and high power applications have not been truly successful yet. To achieve larger force and higher power, multiple miniaturized motors can be combined. This approach, however, is not as simple as it appears at first glance. The electromechanical behaviour of the individual motors differs slightly due to manufacturing and assembly tolerances. The individual motor characteristics are strongly dependent on the driving parameters (frequency, voltage, temperature, pre-stress, etc.) and the driven load and the collective behaviour of the swarm of motors is not just the linear superposition of the individual drive's forces. Thus, the bundle of motors has to be synchronized and controlled appropriately in order to obtain an optimized drive that is not oversized and costly. We have investigated driving and control strategies of a set of linear ultrasonic motors. Our contribution will be divided into three main parts. In part I ultrasonic linear motors will be introduced. In part II driving strategies for a single motor as well as for a bundle of motors will be presented. These concepts will be verified by simulation results and experimental data. In part III a simplified model for the motor's electromechanical behaviour will be given.
Anatomic double-bundle anterior cruciate ligament reconstruction
Institute of Scientific and Technical Information of China (English)
DAI Xue-song
2012-01-01
Objective: To retrospectively evaluate the early results of anatomic double-bundle anterior cruciate ligament (ACL) reconstruction and compare with the results of native ACL of the contralateral knee.Methods: The results of a consecutive series of 118 patients receiving arthroscopic ACL reconstruction were evaluated.Eight patients were lost to the latest follow-up,leaving a total of 110 patients available for study within at least 3 years' clinical follow-up.Among them,63 patients underwent postoperative MRI and CT scan,as well as clinical evaluation.Results: After reconstruction,the knees were stable and pain-free.Mean postoperative Lysholm score was 95.54 in 110 patients after 3 years.CT and MRI assessment showed that the reconstruction centered in the femoral footprint of ACL (n=63).The sagittal ACL angle in the reconstructed ACL (52.16°±2.45°) was much close to that in the contralateral intact ACL (51.31 °±2.18°,P＞0.05).By ACL-Blumensaat line angle analysis,there was no difference between doublebundle reconstructed knees and their contralateral normal knees (4.67°±0.43° vs.4.62°±0.60°,P＞0.05).Conclusion:Anatomic double-bundle ACL reconstruction can place grafts more precisely in the anatomic footprint of the ACL and better restore knee kinematics.
Cortactin Adopts a Globular Conformation and Bundles Actin into Sheets
Energy Technology Data Exchange (ETDEWEB)
Cowieson, Nathan P.; King, Gordon; Cookson, David; Ross, Ian; Huber, Thomas; Hume, David A.; Kobe, Bostjan; Martin, Jennifer L. (Queensland); (Aust. Synch.)
2008-08-21
Cortactin is a filamentous actin-binding protein that plays a pivotal role in translating environmental signals into coordinated rearrangement of the cytoskeleton. The dynamic reorganization of actin in the cytoskeleton drives processes including changes in cell morphology, cell migration, and phagocytosis. In general, structural proteins of the cytoskeleton bind in the N-terminal region of cortactin and regulatory proteins in the C-terminal region. Previous structural studies have reported an extended conformation for cortactin. It is therefore unclear how cortactin facilitates cross-talk between structural proteins and their regulators. In the study presented here, circular dichroism, chemical cross-linking, and small angle x-ray scattering are used to demonstrate that cortactin adopts a globular conformation, thereby bringing distant parts of the molecule into close proximity. In addition, the actin bundling activity of cortactin is characterized, showing that fully polymerized actin filaments are bundled into sheet-like structures. We present a low resolution structure that suggests how the various domains of cortactin interact to coordinate its array of binding partners at sites of actin branching.
Modern Methods of Bundle Adjustment on the Gpu
Hänsch, R.; Drude, I.; Hellwich, O.
2016-06-01
The task to compute 3D reconstructions from large amounts of data has become an active field of research within the last years. Based on an initial estimate provided by structure from motion, bundle adjustment seeks to find a solution that is optimal for all cameras and 3D points. The corresponding nonlinear optimization problem is usually solved by the Levenberg-Marquardt algorithm combined with conjugate gradient descent. While many adaptations and extensions to the classical bundle adjustment approach have been proposed, only few works consider the acceleration potentials of GPU systems. This paper elaborates the possibilities of time and space savings when fitting the implementation strategy to the terms and requirements of realizing a bundler on heterogeneous CPUGPU systems. Instead of focusing on the standard approach of Levenberg-Marquardt optimization alone, nonlinear conjugate gradient descent and alternating resection-intersection are studied as two alternatives. The experiments show that in particular alternating resection-intersection reaches low error rates very fast, but converges to larger error rates than Levenberg-Marquardt. PBA, as one of the current state-of-the-art bundlers, converges slower in 50 % of the test cases and needs 1.5-2 times more memory than the Levenberg- Marquardt implementation.
Block copolymer battery separator
Energy Technology Data Exchange (ETDEWEB)
Wong, David; Balsara, Nitash Pervez
2016-04-26
The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.
U.S. Environmental Protection Agency — This data layer represents Census 2000 demographic data derived from the PL94-171 redistricting files and SF3. Census geographic entities include blocks, blockgroups...
Stern, Margaret
1987-01-01
Extracts from "Experimenting with Numbers" by Margaret Stern demonstrate the use of Stern Blocks to develop the conceptual base on which learning disabled students can build further mathematical skills. (DB)
Steroidal neuromuscular blocking agents
Wierda, JMKH; Mori, K; Ohmura, A; Toyooka, H; Hatano, Y; Shingu, K; Fukuda, K
1998-01-01
Since 1964 approximately 20 steroidal neuromuscular blocking agents have been evaluated clinically. Pancuronium, a bisquaternary compound designed on the drawingboard, was the first steroidal relaxant introduced into clinical practice worldwide in the 1970's. Although a major improvement, pancuroniu
Block copolymer battery separator
Wong, David; Balsara, Nitash Pervez
2016-04-26
The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.
Recipient block TMA technique.
Mirlacher, Martina; Simon, Ronald
2010-01-01
New high-throughput screening technologies have led to the identification of hundreds of genes with a potential role in cancer or other diseases. One way to prioritize the leads obtained in such studies is to analyze a large number of tissues for candidate gene expression. The TMA methodology is now an established and frequently used tool for high-throughput tissue analysis. The recipient block technology is the "classical" method of TMA making. In this method, minute cylindrical tissue punches typically measuring 0.6 mm in diameter are removed from donor tissue blocks and are transferred into empty "recipient" paraffin blocks. Up to 1,000 different tissues can be analyzed in one TMA block. The equipment is affordable and easy to use in places where basic skills in histology are available.
Superalloy Lattice Block Structures
Nathal, M. V.; Whittenberger, J. D.; Hebsur, M. G.; Kantzos, P. T.; Krause, D. L.
2004-01-01
Initial investigations of investment cast superalloy lattice block suggest that this technology will yield a low cost approach to utilize the high temperature strength and environmental resistance of superalloys in lightweight, damage tolerant structural configurations. Work to date has demonstrated that relatively large superalloy lattice block panels can be successfully investment cast from both IN-718 and Mar-M247. These castings exhibited mechanical properties consistent with the strength of the same superalloys measured from more conventional castings. The lattice block structure also accommodates significant deformation without failure, and is defect tolerant in fatigue. The potential of lattice block structures opens new opportunities for the use of superalloys in future generations of aircraft applications that demand strength and environmental resistance at elevated temperatures along with low weight.
DEFF Research Database (Denmark)
Miolane, Charlotte Vikkelsø
ensurethat no attack violatesthe securitybounds specifiedbygeneric attack namely exhaustivekey search and table lookup attacks. This thesis contains a general introduction to cryptography with focus on block ciphers and important block cipher designs, in particular the Advanced Encryption Standard...... by an analytic and systematic approach that allows insight to the techniques. Moreover a new procedure of generating and applying probabilistic equations in algebraic attacks on block cipher is proposed and examined. Also, we present practical results, which to our knowledge are the best algebraic results...... on small scale variants of AES. In the final part of the thesis we present a new block cipher proposal Present and examine its security against algebraic and differential cryptanalysis in particular....
Research on the Pricing of Bundling Information Commodity%信息产品的捆绑定价问题研究
Institute of Scientific and Technical Information of China (English)
毛彦妮; 王刊良; 王龙伟
2003-01-01
This article studies the characteristics of low marginal cost of information commodity and points out that bundling information commodity is surprisingly profitable. After an analysis of the three factors affecting the sales income of bundling information commodity, that is, marginal cost, distribution of consumer' s valuation of bundling commodity and bundling size, a marketing strategy for bundling information commodity is proposed.
Energy Technology Data Exchange (ETDEWEB)
Zinnbauer, M. [Ludwig-Maximilians-Universitaet Muenchen (Germany)
2001-07-01
As most of the electric utilities in Germany have decided by now to adopt the multi-utility strategy for sales promotion in the open electricity market, a questionnaire has been distributed to 1 000 households in order to find out whether product bundling or cross selling in combination with the low-interest product 'electricity' is a good strategy to enlarge the customer basis. EFOplan (Munic University) and the consulting firm Accenture have been in charge of the survey. The results show the current status of insight of household customers and their motives to change supplier, as well as the pattern of demand for product bundling. (orig./CB) [German] Da mittlerweile die meisten EVUs eine Multi-Utility-Strategie anstreben, wurde mittels einer schriftlichen Befragung von 1 000 deutschen Haushalten untersucht, ob die Vermarktung von Zusatz- bzw. Buendelprodukten in Kombination mit dem Low-Interest-Produkt Strom erfolgsversprechend ist. Die Befragung, die von EFOplan (Universitaet Muenchen) in Kooperation mit der Unternehmensberatung Accenture durchgefuehrt wurde, zeigt einerseits den aktuellen Status von Informationsstand und Wechselmotiven beim Stromkauf und andererseits die Bedarfsstruktur im Hinblick auf moegliche Buendelprodukte. (orig.)
Cagimni, Pınar; Govsa, Figen; Ozer, Mehmet Asim; Kazak, Zuhal
2017-02-01
Investigation of the computerized dimensional anatomic location of the greater palatine foramen (GPF) and lesser palatine foramens (LPF) is important indicating site to collect palatal donor tissue, reconstructioning the orofacial area of the oncology patient and applying the greater palatine nerve block anesthesia. The aim of this study is to determine a patient-friendly landmark and to specify the precise location of the GPF in order to standardise certain anatomical marks of safe neurovascular bundle. 120 bony palates were examined to detect the position of the GPF and the LPF related to adjacent anatomical landmarks using a computer software program. The GPF was assessed regarding the position, the diameter and the distances between each foramen and the midline maxillary suture (MMS), the inner border of alveolar ridge (AR), posterior palatal border (PBB), and incisive foramen (IF). The GPF was identified as single in 81 %, double in 16 %, triple in 2 % and absent in 2 % of the specimens. The mean distances between the GPF and the MSS, the GPF and the AR, the GPF and the PPB, the GPF and the IF were 16, 4, 4, and 40 mm, respectively. In majority of the cases, the GPF was seen between the distal surfaces of the third maxillary molar (78 %). Single LPF was observed in 53.45 % of the skulls, two LPF were observed in 31 % of the skulls bilaterally and five LPF were rare in 2.1 % of the specimens. The LPF was most commonly at the junction of the palatine bone and the inner lamella of the pterygoid plate (71.9 %). This study made possible to investigate the variability of the GPF and the feasibility of the greater palatine neurovascular bundle, and to calculate the lengths of some parameters with the help of certain software. To collect the donor tissue of the neurovascular greater palatine network, each distance among the AR-GPF-PPB were equal to 4 mm. To estimate the possible length of the graft, the incision was made along the third and the second molar
Incorporating Endmember Variability into Spectral Mixture Analysis Through Endmember Bundles
Bateson, C. Ann; Asner, Gregory P.; Wessman, Carol A.
1998-01-01
Variation in canopy structure and biochemistry induces a concomitant variation in the top-of-canopy spectral reflectance of a vegetation type. Hence, the use of a single endmember spectrum to track the fractional abundance of a given vegetation cover in a hyperspectral image may result in fractions with considerable error. One solution to the problem of endmember variability is to increase the number of endmembers used in a spectral mixture analysis of the image. For example, there could be several tree endmembers in the analysis because of differences in leaf area index (LAI) and multiple scatterings between leaves and stems. However, it is often difficult in terms of computer or human interaction time to select more than six or seven endmembers and any non-removable noise, as well as the number of uncorrelated bands in the image, limits the number of endmembers that can be discriminated. Moreover, as endmembers proliferate, their interpretation becomes increasingly difficult and often applications simply need the aerial fractions of a few land cover components which comprise most of the scene. In order to incorporate endmember variability into spectral mixture analysis, we propose representing a landscape component type not with one endmember spectrum but with a set or bundle of spectra, each of which is feasible as the spectrum of an instance of the component (e.g., in the case of a tree component, each spectrum could reasonably be the spectral reflectance of a tree canopy). These endmember bundles can be used with nonlinear optimization algorithms to find upper and lower bounds on endmember fractions. This approach to endmember variability naturally evolved from previous work in deriving endmembers from the data itself by fitting a triangle, tetrahedron or, more generally, a simplex to the data cloud reduced in dimension by a principal component analysis. Conceptually, endmember variability could make it difficult to find a simplex that both surrounds the data
Comparison of the Efficacy and Duration of Three Different Methods of Digital Block
Directory of Open Access Journals (Sweden)
M Dehghani
2007-07-01
Full Text Available Introduction & Objective: Finger injuries are very common and majority of them can be treated under digital block anesthesia. Traditional digital block is one of the most commonly performed blocks performed by care providers in several medical fields. There are two other less known methods, transthecal (pulley block, in which local anesthesia is injected into the flexor tendon sheat that needs less volume of anesthesia and hasnot neurovascular complications and subcutaneous block in which local anesthesia is injected subcutaneously at the level of A1 pulley. This study aimed to compare the results of the three methods of digital block. Materials & Methods: A prospective randomized clinical trial was performed at Kashani hospital to compare the less known transthecal (pulley and subcutaneous methods with traditional digital block with regard to the length of anesthesia and need to another anesthetic method (due to insufficient anesthesia as a supplement. We divided 150 patients that were admitted to kashani hospital operating room due to finger injury, randomly, into three groups. In each group the patients were anesthetized by one of the three different methods. All blocks were performed by the same investigator. Data were analyzed by SPSS software using T test. Results: Mean length of anesthesia was 34.2 min’s in the transthecal digital block method and 34 min’s in the subcutaneous method and 33.8 min’s in the traditional digital block method. A repeat injection or local infiltration as a supplement was necessary in 5 instances (7 blocks in the traditional digital block method and 9 instances (11blocks in the subcutaneous method (p<0.05. Conclusion: Regarding fewer injections and less amount of lidocaine and no risk of damaging the neurovascular bundles and comparable length of anesthesia and no need to supplemental anesthesia, transthecal digital block is an appropriate alternative to traditional digital block and subcutaneous injection.
Characterization of midrib vascular bundles of selected medicinal species in Rubiaceae
Nurul-Syahirah, M.; Noraini, T.; Latiff, A.
2016-11-01
An anatomical study was carried out on mature leaves of five selected medicinal species of Rubiaceae from Peninsular Malaysia. The chosen medicinal species were Aidia densiflora, Aidia racemosa, Chasallia chartacea, Hedyotis auricularia and Ixora grandifolia. The objective of this study is to determine the taxonomic value of midrib anatomical characteristics. Leaves samples were collected from Taman Paku Pakis, Universiti Kebangsaan Malaysia, Bangi, Selangor and Kledang Saiong Forest Reserve, Perak, Malaysia. Leaves samples then were fixed in spirit and acetic acid (3:1), the midrib parts then were sectioned using sliding microtome, cleared using Clorox, stained in Safranin and Alcian blue, mounted in Euparal and were observed under light microscope. Findings in this study have shown all species have collateral bundles. The midrib vascular bundles characteristics that can be used as tool to differentiate between species or genus are vascular bundles system (opened or closed), shape and arrangement of main vascular bundles, presence of both additional and medullary vascular bundles, position of additional vascular bundles, shape of medullary vascular bundles, presence of sclerenchyma cells ensheathed the vascular bundles. As a conclusion, midrib anatomical characteristics can be used to identify and discriminate medicinal plants species studied in the Rubiaceae.
A Synthesis of the Peer-Reviewed Differential Bundle Functioning Research
Banks, Kathleen
2013-01-01
The purpose of this article was to present a synthesis of the peer-reviewed differential bundle functioning (DBF) research that has been conducted to date. A total of 16 studies were synthesized according to the following characteristics: tests used and learner groups, organizing principles used for developing bundles, DBF detection methods used,…
Relationships between the Tensile Properties and Tenacity extension Behaviour of Fibre-bundles
Institute of Scientific and Technical Information of China (English)
YU Wei-dong
2002-01-01
Fibre bundle testing is different from single-fibre measurement, not only in testing methods and instruments, but in the results obtained. For wool fibres, Sirolan-TENSOR can supply fibre-bundle tenacity (BS) and bundle extension (BE), but has some limitations on the analysis of the measured tensile curves of fibre bundles. It has not only raised new parameters,such as initial modulus (BM) and specific work of rupture (BW), as well as the specific work before or after the peak-point(WBP or WAP) and the ratios of WAP/WBP and WAP/BW, but also compared the tensile behaviour of different fibre-bundles, e.g. wool,polyester and viscose rayon fibre- bundles. The experimental results from 32 lots of wool tops show that there are correlations between bundle tensile properties,such as BS-BE, BS-BM, BS-BW, BE-BW and BM-BW.However, the variables of coefficients of variance (CV)are almost independent of each other and have no correlation with the average values of fibre bundle tensile parameters, except for BS-CVBM and CVBM-BW.
To Be or Not To Be: The Existential Issue for National Governance Bundles
Millar, C.C.J.M.
2014-01-01
Research Question/Issue The article addresses the issue of whether governance bundles which include both formal and informal governance mechanisms should be classified and compared on the basis of national identity. Research Findings/Insights The governance bundle affecting each firm has formal co
Textbook-Bundled Metacognitive Tools: A Study of LearnSmart's Efficacy in General Chemistry
Thadani, Vandana; Bouvier-Brown, Nicole C.
2016-01-01
College textbook publishers increasingly bundle sophisticated technology-based study tools with their texts. These tools appear promising, but empirical work on their efficacy is needed. We examined whether LearnSmart, a study tool bundled with McGraw-Hill's textbook "Chemistry" (Chang & Goldsby, 2013), improved learning in an…
Lexical Bundles in Discourse Structure: A Corpus-Based Study of Classroom Discourse
Csomay, Eniko
2013-01-01
The present study applies corpus-based methods to document the distributional patterns of previously reported lexical bundle functions as they relate to discourse structure. Specifically, 84 lexical bundles and their discourse functions (Biber "et al." 2004a) were tracked in 1,176 discourse units extracted from the initial phases of 196 university…
Parabolic Bundles on Algebraic Surfaces I -- The Donaldson-Uhlenbeck Compactification
Indian Academy of Sciences (India)
V Balaji; A Dey; R Parthasarathi
2008-02-01
The aim of this paper is to construct the parabolic version of the Donaldson-Uhlenbeck compactification for the moduli space of parabolic stable bundles on an algebraic surface with parabolic structures along a divisor with normal crossing singularities. We prove the non-emptiness of the moduli space of parabolic stable bundles of rank 2.
GPU acceleration of the stochastic grid bundling method for early-exercise options
A. Leitao Rodriguez (Álvaro); C.W. Oosterlee (Cornelis)
2015-01-01
htmlabstractIn this work, a parallel graphics processing units (GPU) version of the Monte Carlo stochastic grid bundling method (SGBM) for pricing multi-dimensional early-exercise options is presented. To extend the method’s applicability, the problem dimensions and the number of bundles will be inc
An Empirical Study on Content Bundling in BitTorrent Swarming System
Han, Jinyoung; Kim, Seungbae; Kim, Hyun-chul; Kwon, Ted "Taekyoung"; Choi, Yanghee
2010-01-01
Despite the tremendous success of BitTorrent, its swarming system suffers from a fundamental limitation: lower or no availability of unpopular contents. Recently, Menasche et al. has shown that bundling is a promising solution to mitigate this availability problem; it improves the availability and reduces download times for unpopular contents by combining multiple files into a single swarm. There also have been studies on bundling strategies and performance issues in bundled swarms. In spite of the recent surge of interest in the benefits of and strategies for bundling, there are still little empirical grounding for understanding, describing, and modeling it. This is the first empirical study that measures and analyzes how prevalent contents bundling is in BitTorrent and how peers access the bundled contents, in comparison to the other non-bundled (i.e., single-filed) ones. To our surprise, we found that around 70% of BitTorrent swarms contain multiple files, which indicate that bundling has become widespread...
On the non-existence of orthogonal instanton bundles on P^{2n+1}
Directory of Open Access Journals (Sweden)
Łucja Farnik
2009-11-01
Full Text Available In this paper we prove that there do not exist orthogonal instanton bundles on P^{2n+1} . In order to demonstrate this fact, we propose a new way of representing the invariant, introduced by L. Costa and G. Ottaviani, related to a rank 2n instanton bundle on P^{2n+1}.
On the noncommutative geometry of the endomorphism algebra of a vector bundle
Masson, Thierry
1999-09-01
In this paper we investigate some aspects of the noncummutative differential geometry based on derivations of the algebra of endomorphism of an oriented complex formation vector bundle. We relate it, in a natural way, to the geometry of the underlying principal bundle, we introduce on it a notion of metric and we study the cohomology of its complex of noncummutative differential forms.
Lexical bundles in an advanced INTOCSU writing class and engineering texts: A functional analysis
Alquraishi, Mohammed Abdulrahman
The purpose of this study is to investigate the functions of lexical bundles in two corpora: a corpus of engineering academic texts and a corpus of IEP advanced writing class texts. This study is concerned with the nature of formulaic language in Pathway IEPs and engineering texts, and whether those types of texts show similar or distinctive formulaic functions. Moreover, the study looked into lexical bundles found in an engineering 1.26 million-word corpus and an ESL 65000-word corpus using a concordancing program. The study then analyzed the functions of those lexical bundles and compared them statistically using chi-square tests. Additionally, the results of this investigation showed 236 unique frequent lexical bundles in the engineering corpus and 37 bundles in the pathway corpus. Also, the study identified several differences between the density and functions of lexical bundles in the two corpora. These differences were evident in the distribution of functions of lexical bundles and the minimal overlap of lexical bundles found in the two corpora. The results of this study call for more attention to formulaic language at ESP and EAP programs.
Overview of flowline bundle technology from concept selection to offshore installation
Institute of Scientific and Technical Information of China (English)
Song Ruxin; Xia Qiuling
2013-01-01
Flowline bundle system consisting of carrier pipe,sleeve pipe and internal flowlines offers innovative solution for the infield transportation of oil and gas.Due to its features,flowline bundle offers a couple of advantages over conventional flowline in particular for cases where multi-flowlines and high thermal performance is of great interest.The main benefits and advantages of such system include excellent thermal performance to prevent wax formation and hydrates,multiple bundled flowlines,mechanical and corrosion protection,potential reuse,etc.With the developments of offshore oil and gas industries,more and more hydrocarbon resources are being explored and discovered from shallow to deep water.Pipeline bundle system can be a smart solution for certain applications,which can be safe and cost effective solution.The objective of this paper is to overview pipeline bundle technology,outline detailed engineering design issue and procedure.Focus is given to its potential application in offshore for infield transportation.Engineering design principles and procedures for pipeline bundle system are highlighted.Construction methods of flowline bundle onshore are reviewed.Offshore towing and installation of pipeline bundle procedure is outlined.
GPU acceleration of the stochastic grid bundling method for early-exercise options
Leitao Rodriguez, A.; Oosterlee, C.W.
2015-01-01
In this work, a parallel graphics processing units (GPU) version of the Monte Carlo stochastic grid bundling method (SGBM) for pricing multi-dimensional early-exercise options is presented. To extend the method’s applicability, the problem dimensions and the number of bundles will be increased drast