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Kinds of Contours Terms modified by Contours Selected AbstractsDETERMINATION OF FAULT SLIP COMPONENTS USING SUBSURFACE STRUCTURAL CONTOURS: METHODS AND EXAMPLESJOURNAL OF PETROLEUM GEOLOGY, Issue 3 2004S-S. Xu Problems with measuring fault slip in the subsurface can sometimes be overcome by using subsurface structural contour maps constructed from well logs and seismic information. These maps are useful for estimating fault slip since fault motion commonly causes the dislocation of structural contours. The dislocation of a contour is defined here as the distance in the direction of fault strike between two contours which have the same value on both sides of a fault. This dislocation can be estimated for tilted beds and folded beds as follows: (i),If a dip-slip fault offsets a tilted bed, the dislocation (Sc) of contours can be estimated from the vertical component (Sv) of the fault slip and the dip (,) of the bedding according to the following relationship: Sc= Sv/tan ,. Since Sc and , can be measured from a contour map, the vertical component of fault slip can be obtained from this equation. If a strike-slip fault offsets a tilted bed, the dislocation (Scs) of contours is equal to the strike-slip of the fault (Sc), that is, Scs= Ss. (ii),If a fault offsets a symmetric fold, the strike component (Scs) of fault slip and the dislocation of the contours (Sc) can be calculated, respectively, from the equations Scs= (Smax+ Smin) / 2 and Sc= (Smax - Smin) / 2. Smax is the greater total dislocation (Sc+ Scs) of a contour line between the two limbs of the fold and Smin is the smaller total dislocation (Sc - Scs) for the same contour line. In this case, Sv can be also calculated using the obtained value of Sc and the equation Sv= Sc tan ,. Similarly, for an asymmetric fold, the dislocation of contours due to the vertical slip component is Scb= (Smax - Smin)/(n + 1), and the strike-slip component is Ss= Scs= (nSmin+ Smax/(n + 1), where n is the ratio between the values of interlines of the two limbs, and Scb is the dislocation of contours due to the vertical slip component for either of the two limbs (here it is for limb b). In all cases, three conditions are required for the calculation of contour dislocation: (i),the contour lines must be approximately perpendicular to the fault strike; the intersection angle between the fault strike and the strike of bedding should be greater than 65°; (ii),the bed must not be dip more than 35°; and (iii),folding or flexure of the stratigraphic horizons must have occurred before faulting. These methods for determining fault slip from the dislocation of structural contours are discussed using case studies from the Cantarell oilfield complex, Campeche Sound (southern Gulf of Mexico), the Jordan-Penwell Ellenburger oilfield in Texas, and the Wilmington oilfield in California. [source] CONTOURS OF AN ANTHROPOLOGY OF THE CHINESE STATE: POLITICAL STRUCTURE, AGENCY AND ECONOMIC DEVELOPMENT IN RURAL CHINATHE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 3 2004Frank N. Pieke Anthropologists have long been inclined to view China from the perspective of a state-society dichotomy. In this model, the inevitable consequence of economic reform is that , especially at the local level , the state must yield more and more of its power to entrepreneurs, foreign investors, non-state organizations, and local communities. Not only does this approach distort the role of the state in society, but by placing the state above and outside society it also excludes it from the anthropological gaze. This article proposes an anthropology of the Chinese state which does not merely view the state in society, but also investigates the state itself as society. Drawing on fieldwork in northeastern Yunnan province, I illustrate this general point by investigating the changing role of the local state in economic development. This agenda for an anthropology of the Chinese state resonates both with the recent ,reinvention' of the subfield of political anthropology with its focus on governmentality, policy, and rights, and with recent calls by political scientists for the development of an interdisciplinary anthropology of the developmental state. [source] ERROR SPACE MOTION CONTROL METHODOLOGY FOR COMPLEX CONTOURSASIAN JOURNAL OF CONTROL, Issue 1 2005Robert G. Landers ABSTRACT Motion control is a critical component of many engineering systems (e.g., manufacturing, robotics). Most systems have standard interpolation and control schemes for linear and circular contours; therefore, complex contours are often decomposed into a series of line segments and circular arcs. However, there are discontinuities where the line segments and arcs are joined together, and time to complete the contour is substantially increased when acceleration/deceleration interpolation schemes are employed. A motion control scheme known as the error space motion control methodology is proposed in this paper to design servomechanism motion control systems that may be utilized for complex contours. The error space motion control methodology is applied to a two-axis motion control system and simulation studies are conducted for linear, circular, elliptical, and limacon contours. The results demonstrate the excellent tracking ability of the proposed error space motion control methodology and its utility for complex contours. [source] Electrophysiologic Effects of Placing Cochlear Implant Electrodes in a Perimodiolar Position in Young Children,THE LARYNGOSCOPE, Issue 1 2004Phillip A. Wackym MD Abstract Objective The purpose of this study was to intraoperatively record the electrically evoked auditory brainstem response (EABR) before and after placement of the electrode positioning system (EPS) (CII Bionic Ear with HiFocus I cochlear implant electrode array) as well as before and after stylet removal (Nucleus Contour cochlear implant electrode array). It was hypothesized that physiologic changes would occur after perimodiolar positioning of the electrode array and these changes would be evident from the EABR recordings. Study Design Consecutive young (11,36 month old) pediatric cochlear implant recipients (n = 17) had intraoperative EABRs recorded from three intracochlear electrodes that represented apical, medial, and basal locations. Wave V amplitudes and thresholds were studied relative to electrode location and pre- versus postperimodiolar positioning. These evoked potential measures were analyzed for statistical significance. Setting Tertiary referral children's hospital/medical college. Results Wave V thresholds of the EABR were lower, and amplitudes were larger after perimodiolar positioning, although the changes were dependent on electrode location and implant design. Statistically significant decreases in EABR wave V threshold and increases in suprathreshold wave V amplitude were found for the basal electrode for the CII Bionic Ear HiFocus I and for the apical electrode for the Nucleus Contour. Conclusions Placement of either the CII Bionic Ear HiFocus I or Nucleus Contour cochlear implant electrode array in the perimodiolar position in young children resulted in less electrical current necessary to stimulate the auditory system. Changes in electrophysiologic thresholds and amplitudes, measured with EABR, indicate that the electrode array is placed closer to the modiolus with both electrode designs. [source] The retinal nerve fiber layer and the optic nerve head morphology after glaucoma surgeryACTA OPHTHALMOLOGICA, Issue 2009T GRACNER Purpose To detect and quantify changes in the retinal nerve fiber layer (RNFL) and the optic nerve head (ONH) morphology after glaucoma surgery. Methods 13 eyes of 13 patients with open-angle glaucoma in which goniotrephining with scleral flap without intraoperative antimetabolites for progressive glaucoma damage was done were included in this prospective study. Before and 6 months after the surgery: the intraocular pressure (IOP) was measured, the thicknes of the RNFL was measured with a scanning laser polarimeter (GDx VCC), the confocal scanning laser ophthalmoscopy measurements of ONH with Heidelberg retina tomograph (HRT 3) were performed and the visual field was tested with Humphrey Field Analyser. Results The mean IOP before surgery was 24.5 ? 2.3 mmHg decreasing 6 months after to a mean of 13.9 ? 3.0 mmHg (p<0.05). The RNFL measurements with GDx VCC revealed no differences between the mean TSNIT Avarage (p=0.383), mean Superior Avarage (p=0.756) and mean Inferior Avarage (p=0.269) before and after surgery. The ONH measurements with HRT 3 revealed postoperatively a significant increase in the mean Rim Area, Rim Volume and Cup Shape Measure, whereas Cup Area, Cup Volume and Linear Cup/Disc Ratio decreased (p<0.05). There were no differences between the mean Height Variation Contour (p=0.678) and Mean RNFL Thickness (p=0.064) before and after surgery. Preoperatively the mean value of the Mean Deviation on automated perimetry was ,18.82 ? 8.5 dB improving 6 months postoperatively to a mean of ,16.63 ? 7.9 dB (p<0.05). Conclusion Our study demonstrated the beneficial effect of IOP reduction obtained with glaucoma surgery on visual field indices and ONH parameters evaluated by HRT 3. [source] Introduction: Contours of a Research Project and Early FindingsIDS BULLETIN, Issue 6 2007Peter P. Houtzager First page of article [source] Contours of Christology in the New Testament , Edited by Richard N. LongeneckerRELIGIOUS STUDIES REVIEW, Issue 2 2006Casimir Bernas No abstract is available for this article. [source] Contours of the World Economy, 1,2030AD: Essays in Macro-Economic HistoryAUSTRALIAN ECONOMIC HISTORY REVIEW, Issue 2 2009Les Oxley No abstract is available for this article. [source] Single Implants and Buccal Bone Grafts in the Anterior Maxilla: Measurements of Buccal Crestal Contours in a 6-Year Prospective Clinical StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2005Odont Dr/PhD, Torsten Jemt DDS ABSTRACT Background: Patients provided with buccal bone grafts seem to lose a substantial part of the graft in the short term. Purpose: To measure long-term changes in buccal and proximal tissue volumes after local bone grafting and single implant treatment. Materials and Methods: Eight of 10 originally treated male patients were followed up for 6 years after treatment with buccal bone grafts in the central incisor region. After a healing time of 6 months, a two-stage implant surgery procedure was performed followed by single crown placement. Clinical photographs and impressions were taken prior to the surgical interventions and after crown placement and at first and fifth annual checkups. The photographs were analyzed with regard to papilla regeneration by means of a clinical papilla index. The models were used to measure the clinical length of teeth and tooth movements adjacent to the implants. Changes in buccal crest volume during the study period were measured by means of optical scanning of obtained study models. Results: Papillae volume increased significantly (p < .05) during the first year, thereafter showing a slow further increase during the 4 following years. Three of the patients (38%) presented small movements of their adjacent central incisor in a vertical or palatal direction of less than 1 mm during the follow-up period. All patients showed resorption during the first year after grafting (p < .01), in which three patients (38%) had lost basically all of increased volume at second surgery. After abutment or crown placement, all patients showed an increased volume (p < .01), followed by an average reduction during the first year, reaching a significant level in the apical part of the crest (p < .05). Thereafter, a relatively stable average situation was observed during the following 4 years, with individual variations, however. Conclusion: Local bone grafting seems to create sufficient bone volume for implant placement after 6 months, but individual variations in resorption pattern make the grafting procedure unpredictable for long-term prognosis. Instead, the abutment and the crown seem to play a more important role for building up and maintaining the buccal contour in the coronal part of the crest long term. [source] Handwritten Thai Character Recognition Using Fourier Descriptors and Genetic Neural NetworksCOMPUTATIONAL INTELLIGENCE, Issue 3 2002Pisit Phokharatkul This article presents a method to solve the rotated and scaling character recognition problem using Fourier descriptors and genetic neural networks. The contours of character image are extracted and separated between the outer contour and inner or loop contours. The loop contours are a special characteristic of Thai characters, called the head of the character. The special features of Thai characters (loop contours) are used at the rough classification stage, and Fourier descriptors with genetic neural networks are used at the fine classification stage. The Fourier descriptors detect the outer contour of a character and it is fed to network. These features are recognized by a multilayer neural network. Genetic algorithms (GAs) are utilized to help compute the weights of the neural network optimally and reduce uncertain states in the neural networks output. Experimental results have shown that the combination of the Fourier descriptors with genetic neural networks, loop features, and local curvature charateristics of similar characters are powerful tools for successfully classifying Thai characters. The recognition rate by this method is 99.12% for 1200 examples of handwritten Thai words (a total of 13,500 characters) written by 60 persons. [source] Sub-Voxel Topology Control for Level-Set SurfacesCOMPUTER GRAPHICS FORUM, Issue 3 2003Stephan Bischoff Active contour models are an efficient, accurate, and robust tool for the segmentation of 2D and 3D image data. In particular, geometric deformable models (GDM) that represent an active contour as the level set of an implicitfunction have proven to be very effective. GDMs, however, do not provide any topology control, i.e. contours maymerge or split arbitrarily and hence change the genus of the reconstructed surface. This behavior is inadequate insettings like the segmentation of organic tissue or other objects whose genus is known beforehand. In this paperwe describe a novel method to overcome this limitation while still preserving the favorable properties of the GDMsetup. We achieve this by adding (sparse) topological information to the volume representation at locations whereit is necessary to locally resolve topological ambiguities. Since the sparse topology information is attached to theedges of the voxel grid, we can reconstruct the interfaces where the deformable surface touches itself at sub-voxelaccuracy. We also demonstrate the efficiency and robustness of our method. [source] Drawing for Illustration and Annotation in 3DCOMPUTER GRAPHICS FORUM, Issue 3 2001David Bourguignon We present a system for sketching in 3D, which strives to preserve the degree of expression, imagination, and simplicity of use achieved by 2D drawing. Our system directly uses user-drawn strokes to infer the sketches representing the same scene from different viewpoints, rather than attempting to reconstruct a 3D model. This is achieved by interpreting strokes as indications of a local surface silhouette or contour. Strokes thus deform and disappear progressively as we move away from the original viewpoint. They may be occluded by objects indicated by other strokes, or, in contrast, be drawn above such objects. The user draws on a plane which can be positioned explicitly or relative to other objects or strokes in the sketch. Our system is interactive, since we use fast algorithms and graphics hardware for rendering. We present applications to education, design, architecture and fashion, where 3D sketches can be used alone or as an annotation of an existing 3D model. [source] The Synthesis of Rock Textures in Chinese Landscape PaintingCOMPUTER GRAPHICS FORUM, Issue 3 2001Der-Lor Way In Chinese landscape painting, rock textures portray the orientation of mountains and contribute to the atmosphere. Many landscape-painting skills are required according to the type of rock. Landscape painting is the major theme of Chinese painting. Over the centuries, masters of Chinese landscape painting developed various texture strokes. Hemp-fiber and axe-cut are two major types of texture strokes. A slightly sinuous and seemingly broken line, the hemp-fiber stroke is used for describing the gentle slopes of rock formations whereas the axe-cut stroke best depicts hard, rocky surfaces. This paper presents a novel method of synthesizing rock textures in Chinese landscape painting, useful not only to artists who want to paint interactively, but also in automated rendering of natural scenes. The method proposed underwrites the complete painting process after users have specified only the contour and parameters. [source] An Ultrasonic Profiling Method for the Inspection of Tubular StructuresCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2007Francisco Gomez These graphs not only show the inner contour of the pipe but also integrate the intensity of the echoes employed to create the profile. The enhanced profile is generated by superimposing the peak intensity from the returning echoes at the calculated x, y, and z coordinates where it reflected from the pipe wall. The proposed method is capable of showing anomalous conditions, inside pipes filled with liquid, with dimensions smaller than the theoretical lateral and axial resolution of the transducer, in contrast to traditional methods where these kinds of defects are not disclosed. The proposed inspection method and its capabilities were validated through the realization of simulations and experiments. The presented approach was particularly developed with the aim of scanning internal sections of pipes filled with liquid using rotary ultrasonic sonars, but it is expected that this research could be expanded to the inspection of other submerged structures, such as water tanks, or pressurized vessels. [source] An in vitro model system for cytoskeletal confinementCYTOSKELETON, Issue 10 2009Sarah Köster Abstract The motility, shape, and functionality of the cell depend sensitively on cytoskeletal mechanics which in turn is governed by the properties of filamentous proteins - mainly actin, microtubules, and intermediate filaments. These biopolymers are confined in the dense cytoplasm and therefore experience strong geometric constraints on their equilibrium thermal fluctuations. To obtain a better understanding of the influence of confinement on cytoskeletal filaments we study the thermal fluctuations of individual actin filaments in a microfluidic in vitro system by fluorescence microscopy and determine the persistence length of the filaments by analyzing the radial distribution function. A unique feature of this method is that we obtain the persistence length without detailed knowledge of the complete contour of the filament which makes the technique applicable to a broad range of biological polymers, including those with a persistence length smaller than the optical resolution. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source] Cryolipolysis for Noninvasive Fat Cell Destruction: Initial Results from a Pig ModelDERMATOLOGIC SURGERY, Issue 10 2009BRIAN ZELICKSON MD BACKGROUND Liposuction is one of the most frequently performed cosmetic procedures in the United States, but its cost and downtime has led to the development of noninvasive approaches for adipose tissue reduction. OBJECTIVE To determine whether noninvasive controlled and selective destruction of fat cells (Cryolipolysis) can selectively damage subcutaneous fat without causing damage to the overlying skin or rise in lipid levels. METHODS Three Yucatan pigs underwent Cryolipolysis at 22 sites: 20 at cooling intensity factor (CIF) index 24.5 (,43.8 mW/cm2), one at CIF 24.9 (,44.7 mW/cm2), and one at CIF 25.4 (,45.6 mW/cm2). Treated areas were evaluated using photography, ultrasound, and gross and microscopic pathology. Lipids were at various times points. One additional pig underwent Cryolipolysis at various days before euthanasia. RESULTS The treatments resulted in a significant reduction in the superficial fat layer without damage to the overlying skin. An inflammatory response triggered by cold-induced apoptosis of adipocytes preceded the reduction in the fat layer. Evaluation of lipids over a 3-month period following treatment demonstrated that cholesterol and triglyceride values remained normal. CONCLUSIONS Cryolipolysis is worthy of further study because it has been shown to significantly decrease subcutaneous fat and change body contour without causing damage to the overlying skin and surrounding structures or deleterious changes in blood lipids. [source] Full Scope of Effect of Facial Lipoatrophy: A Framework of Disease UnderstandingDERMATOLOGIC SURGERY, Issue 8 2006BENJAMIN ASCHER MD BACKGROUND Facial lipoatrophy has been observed to occur in a variety of patient populations, with inherited or acquired disease, or even in aging patients as a natural progression of tissue change over time. There is currently no framework from which physicians of all medical specialties can communally discuss the manifestations, diagnoses, and management of facial lipoatrophy. OBJECTIVE The aim of this assembly was to derive a definition of facial lipoatrophy capable of being applied to all patient populations and develop an accompanying grading system. RESULTS The final consensus of the Facial Lipoatrophy Panel encompasses both aging and disease states: "Loss of facial fat due to aging, trauma or disease, manifested by flattening or indentation of normally convex contours." The proposed grading scale includes five gradations (Grades 1,5; 5 being the most severe), and the face is assessed according to three criteria: contour, bony prominence, and visibility of musculature. CONCLUSION Categorizing the presentation of facial lipoatrophy is subjective and qualitative, and will need to be validated with objective measures. Furthermore, during the assembly, several topics were exposed that warrant further research, including the physiology of volume loss, age and lipoatrophy, and human immunodeficiency virus and lipoatrophy. [source] Minimal-Scar Segmental Extraction of Lipomas: Study of 122 Consecutive ProceduresDERMATOLOGIC SURGERY, Issue 1 2005Rajiv Y. Chandawarkar MD Background Surgical extirpation of lipomas that occur in cosmetically conspicuous areas of the body leaves a visible scar that is usually disfiguring. Minimal-scar segmental extraction (MSE) employs a much smaller incision and extraction and is particularly useful in exposed parts of the body. It can be easily performed in an office setting. Objective The objective of this study was to evaluate the merits of MSE in clinical practice. Unlike other reports in the literature that describe, anecdotally, minimally invasive methods of lipoma removal, our study examined a new method by carefully measuring the results in a larger group of consecutive patients treated using this technique. Materials and Methods A retrospective study was performed using data from 91 consecutive patients with a total of 122 lipomas that were treated using MSE. MSE of lipomas consists of a small stab incision and blind dissection of the tumor followed by its extraction in a segmental fashion. This procedure involves small instrumentation, minimal dissection with preservation of contour, and complete removal of the lipoma, including substantial portions of the capsule. Clinical data, including complications, outcomes, and recurrence rates, were recorded. Results The procedure was well tolerated by patients, who were pleased with the results, particularly the small scar. The incidence of complications was 1.6% (n= 2) and consisted of hematoma (n= 1) and seroma (n= 1). The recurrence rate was 0.8% (n= 1). No long-term morbidity was noted. Conclusions The technical ease with which the MSE can be performed, coupled with a low recurrence rate, makes it a very cost-effective operation. The smaller postoperative scars, rapid healing, and low morbidity allow for better patient acceptance. We recognize the advantages and limitations of this procedure and encourage its use in selected patients. RAJIV Y. CHANDAWARKAR, MD, PEDRO RODRIGUEZ, MD, JOHN ROUSSALIS, MD, AND M. DEVIPRASAD TANTRI, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Areolar Cosmetic Tattoo Ink Darkening: A Complication of Q-Switched Alexandrite Laser TreatmentDERMATOLOGIC SURGERY, Issue 1 2002Sung-Eun Chang MD background and objective. Medical tattooing of the areola is widely performed in Korea. However, cosmetic tattoos containing flesh-tone, purple-red, and yellow dyes are sometimes resistant to Q-switched laser and may even become darker. method. Two Korean women in their 30s who had a mastectomy got light brown to red areolar medical tattoos but they were not satisfied with the shape and size of the tattoos. They underwent Q-switched alexandrite laser treatment with a 3 mm collimated beam at fluences of 7.5,8 J/cm2 in order to trim the irregular contour and reduce the diameter of the tattoos. results. Within 5 minutes a dark gray to black discoloration of the treated area was evident and remained dark for 6 weeks. Improvement was not noted after two further Q-switched Nd:YAG laser treatments. conclusion. Medical areolar tattoos should be approached with extra caution when attempting their removal with high-energy pulsed lasers such as Q-switched alexandrite laser and a small test site should be performed prior to treatment. [source] Steering the brand in the auto industryDESIGN MANAGEMENT REVIEW, Issue 1 2003Anne Asensio At General Motors, the goal is to give each automotive line a distinctive brand character. In this interview, Anne Asensio discusses how she and her design colleagues contribute to this effort. From contour to features, these elements are used to reinforce brand character and build an emotional bond with consumers. It is intense and exciting work in which quality,from conception to execution,is a key aspect of success. [source] Electrocardiogram Differentiation of Benign Early Repolarization Versus Acute Myocardial Infarction by Emergency Physicians and CardiologistsACADEMIC EMERGENCY MEDICINE, Issue 9 2006Samuel D. Turnipseed MD Abstract Objectives: ST-segment elevation (STE) related to benign early repolarization (BER), a common normal variant, can be difficult to distinguish from acute myocardial infarction (AMI). The authors compared the electrocardiogram (ECG) interpretations of these two entities by emergency physicians (EPs) and cardiologists. Methods: Twenty-five cases (13 BER, 12 AMI) of patients presenting to the emergency department with chest pain were identified. Criteria for BER required four of the following: 1) widespread STE (precordial greater than limb leads), 2) J-point elevation, 3) concavity of initial up-sloping portion of ST segment, 4) notching or irregular contour of J point, and 5) prominent, concordant T waves. Additional BER criteria were 1) stable ECG pattern, 2) negative cardiac injury markers, and 3) normal cardiac stress test or angiography. AMI criteria were 1) regional STE, 2) positive cardiac injury markers, and 3) identification of culprit coronary artery by angiography in less than eight hours of presentation. The 25 ECGs were distributed to 12 EPs and 12 cardiologists (four in academic medicine, four in community practice, and four in community academics [health maintenance organization] in each physician group). The physicians were informed of the patients' age, gender, and race, and they then interpreted the ECGs as BER or AMI. Undercalls (AMI misdiagnosed as BER) and overcalls (BER misdiagnosed as AMI) were calculated for each physician group. Results: Cardiologists correctly interpreted 90% of ECGs, and EPs correctly interpreted 81% of ECGs. The proportion of undercalls (missed AMI/total AMI) was 2.8% for cardiologists (95% confidence interval [CI] = 0.09% to 5.5%) compared with 9.7% for EPs (95% CI = 4.8% to 14.6%) (p = 0.02). The proportion of overcalls (missed BER/total BER) was 17.3% for cardiologists (95% CI = 11.4% to 23.3%) versus 27.6% for EPs (95% CI = 20.6% to 34.6%) (p = 0.03). The mean number of years in practice was 19.8 for cardiologists (95% CI = 19 to 20.5) and 11 years for EPs (95% CI = 10.5 to 12.0) (p < 0.001). Conclusions: Although correct interpretation was high in both groups, cardiologists, who had significantly more years of practice, had fewer misinterpretations than EPs in distinguishing BER from AMI electrocardiographically. [source] Non-linear behavior of mass concrete in three-dimensional problems using a smeared crack approachEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 3 2005H. Mirzabozorg Abstract A smeared crack approach has been proposed to model the static and dynamic behavior of mass concrete in three-dimensional space. The proposed model simulates the tensile fracture on the mass concrete and contains pre-softening behavior, softening initiation, fracture energy conservation and strain rate effects under dynamic loads. The validity of the proposed model has been checked using the available experimental results under static and dynamic loads. The direct and indirect displacement control algorithms have been employed under incremental increasing static loads. It was found that the proposed model gives excellent results and crack profiles when compared with the available data under static loads. The Koyna Dam in India has been used to verify the dynamic behavior of the proposed model. It was found that the resulting crack profiles were in good agreement with the available experimental results. Finally, the Morrow Point Dam was analyzed, including the dam,reservoir interaction effects, to consider its non-linear seismic behavior. It was found that the resulting crack profiles were in good agreement with the contour of maximum principal stresses and no numerical instability occurred during the analysis. Copyright © 2004 John Wiley & Sons, Ltd. [source] Use of chemometric methodology in optimizing conditions for competitive binding partial filling affinity capillary electrophoresisELECTROPHORESIS, Issue 16 2008Ruth E. Montes Abstract This work expands the knowledge of the use of chemometric response surface methodology (RSM) in optimizing conditions for competitive binding partial filling ACE (PFACE). Specifically, RSM in the form of a Box,Behnken design was implemented in flow-through PFACE (FTPFACE) to effectively predict the significance of injection time, voltage, and neutral ligand (neutral arylsulfonamide) concentration, [Lo], on protein,neutral ligand binding. Statistical analysis results were used to create a model for response surface prediction via contour and surface plots at a given maximum response (,RMTR) to reach a targeted Kb,=,2.50×106,M,1. The adequacy of the model was then validated by experimental runs at the optimal predicted solution (injection time,=,2.3,min, voltage,=,11.6,kV, [Lo],=,1.4,,M). The achieved results greatly extend the usefulness of chemometrics in ACE and provide a valuable statistical tool for the study of other receptor,ligand combinations. [source] Implementation of chemometric methodology in ACE: Predictive investigation of protein,ligand bindingELECTROPHORESIS, Issue 16 2007Grady Hanrahan Abstract An ACE predictive investigation of protein,ligand binding using a highly effective chemometric response surface design technique is presented. Here, Kd was estimated using one noninteracting standard which relates to changes in the electrophoretic mobility of carbonic anhydrase B (CAB, EC 4.2.1.1) on complexation with the ligand 4-carboxybenzenesulfonamide (CBSA) present in the electrophoresis buffer. Experimental factors including injection time, capillary length, and applied voltage were selected and tested at three levels in a Box,Behnken design. Statistical analysis results were used to create a mathematical model for response surface prediction via contour and surface plots at a given target response (Kd,=,1.19×10,6,M). As expected, there were a number of predicted solutions that reached our target response based on the significance of each factor at appropriate levels. The adequacy of the model was validated by experimental runs with the predicted model solution (capillary length,=,47,cm, voltage,=,11,kV, injection time,=,0.01,min) presented in detail as an example. [source] Arthroscopic reattachment of osteochondritis dissecans lesions using resorbable polydioxanone pinsEQUINE VETERINARY JOURNAL, Issue 5 2004A. J. NIXON Summary Reasons for performing study: Debridement of osteochondritis dissecans (OCD) cartilage lesions results in fibrocartilage and imperfect hyaline repair tissue, and forms a permanent irregularity to the subchondral bone plate. Objective: To evaluate the clinical, radiographic and outcome effects of OCD cartilage flap reattachment for select lesions as an alternative to OCD debridement. Hypothesis: Separated cartilage flaps resulting from OCD lesions may be re-incorporated into the hyaline cartilage surface by reattachment rather than debridement and removal. Methods: Resorbable polydioxanone pins were used to reattach OCD flap lesions in 16 joints of 12 horses. Criteria for attachment, rather than removal, included an unmineralised cartilage flap on preoperative radiographs and a relatively smooth surface with some residual perimeter attachment at surgery. Results: There were 12 subjects, 6 males and 6 females, 7 Thoroughbred or Standardbred weanlings, 3 Warmbloods, 1 Arabian and 1 Quarter Horse, mean age at surgery 6.8 months. All horses had effusion of the affected femoropatellar joint (n = 9), tarsocrural joint (n = 1) or fetlock (n = 2). Radiographic lesions varied in length between 1.8,6.3 cm; reattachment was used in 16 of 18 affected joints and the OCD cartilage was not satisfactory for salvage in 2 stifles. Number of pins required was 2,10. One horse was subjected to euthanasia due to a tendon laceration 8 weeks after surgery; of the remaining 11 horses, mean duration of follow-up was 3.9 years (range 4 months-8 years). Nine of these were sound and had entered work, while 2 were sound but remained unbroken 4 and 6 months post operatively, respectively. Radiographic resolution of the OCD lesion occurred in 14 of 16 pinned joints in the 9 horses with long-term follow-up. The 2 remaining joints had a 3 and a 5 mm mineralised flap in the original defect sites. Conclusions: This study indicated cartilage flap reattachment was an alternative to removal in selected OCD lesions. Potential relevance: Relatively smooth OCD cartilage flaps may be salvaged by reattachment and can result in normal radiographic subchondral contour and a high likelihood of athletic performance. Further case numbers are required to determine which lesions are too irregular or contain too much mineral for effective incorporation after reattachment. [source] Diversity of the Vocal Signals of Concave-Eared Torrent Frogs (Odorrana tormota): Evidence for Individual SignaturesETHOLOGY, Issue 11 2009Albert S. Feng Male concave-eared torrent frogs (Odorrana tormota) have an unusually large call repertoire and have been shown to communicate ultrasonically. We investigated the individual specificity of male advertisement calls in order to explore the acoustic bases of individual recognition, which was demonstrated in an accompanying study. Vocalizations of 15 marked males were recorded in the field. A quantitative analysis of the signals revealed eight basic call-types. Two of them (the single- and multi-note long-calls) were investigated in more detail. Long-calls were characterized by pronounced and varying frequency modulation patterns, and abundant occurrence of nonlinear phenomena (NLP), i.e., frequency jumps, subharmonics, biphonations and deterministic chaos. The occurrence of NLP was predictable from the contour of the fundamental frequency in the harmonic segment preceding the onset of the NLP, and this prediction showed individual-specific patterns. Fifteen acoustic variables of the long calls were measured, all of which were significantly different among individuals, except biphonic segment duration. Discriminant function analysis (DFA) showed that 54.6% of the calls could be correctly assigned to individual frogs. The correct classification was above chance level, suggesting that individual specificity of calls underlie the ability of males to behaviorally discriminate the vocal signals of their neighbors from those of strangers, a remarkable feat for a frog species with a diverse vocal repertoire. The DFA classification results were lower than those for other anurans, however. We hypothesize that there is a tradeoff between an increase in the fundamental frequency of vocalizations to avoid masking by low-frequency ambient background noise, and a decrease in individual-specific vocal tract information extractable from the signal. [source] Individual Acoustic Variation in Fallow Deer (Dama dama) Common and Harsh Groans: A Source-Filter Theory PerspectiveETHOLOGY, Issue 3 2007Elisabetta Vannoni Mammals are able to distinguish conspecifics based on vocal cues, and the acoustic structure of mammal vocalizations is directly affected by the anatomy and action of the vocal apparatus. However, most studies investigating individual patterns in acoustic signals do not consider a vocal production-based perspective. In this study, we used the source-filter model of vocal production as a basis for investigating the acoustic variability of fallow deer groans. Using this approach, we quantified the potential of each acoustic component to carry information about individual identity. We also investigated if cues to individual identity carry over among the two groan types we describe: common and harsh groans. Using discriminant function analysis, we found that variables related to the fundamental frequency contour and the minimum frequencies of the highest formants contributed most to the identification of a given common groan. Common groans were individually distinctive with 36.6% (53.6% with stepwise procedure) of groans assigned to the correct individual. This level of discrimination is approximately six times higher than that predicted by chance. In addition, univariate anovas showed significant inter-individual variation in the minimum formant frequencies when common and harsh groans were combined, suggesting that some information about individuality is shared between groan types. Our results suggest that the sound source and the vocal tract resonances act together to determine groan individuality and that enough variation exists to potentially allow individual recognition based on groans. [source] Early processing in the human lateral occipital complex is highly responsive to illusory contours but not to salient regionsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2009Marina Shpaner Abstract Human electrophysiological studies support a model whereby sensitivity to so-called illusory contour stimuli is first seen within the lateral occipital complex. A challenge to this model posits that the lateral occipital complex is a general site for crude region-based segmentation, based on findings of equivalent hemodynamic activations in the lateral occipital complex to illusory contour and so-called salient region stimuli, a stimulus class that lacks the classic bounding contours of illusory contours. Using high-density electrical mapping of visual evoked potentials, we show that early lateral occipital cortex activity is substantially stronger to illusory contour than to salient region stimuli, whereas later lateral occipital complex activity is stronger to salient region than to illusory contour stimuli. Our results suggest that equivalent hemodynamic activity to illusory contour and salient region stimuli probably reflects temporally integrated responses, a result of the poor temporal resolution of hemodynamic imaging. The temporal precision of visual evoked potentials is critical for establishing viable models of completion processes and visual scene analysis. We propose that crude spatial segmentation analyses, which are insensitive to illusory contours, occur first within dorsal visual regions, not the lateral occipital complex, and that initial illusory contour sensitivity is a function of the lateral occipital complex. [source] The representation of Kanizsa illusory contours in the monkey inferior temporal cortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2008Gy. Sáry Abstract Stimulus reduction is an effective way to study visual performance. Cues such as surface characteristics, colour and inner lines can be removed from stimuli, revealing how the change affects recognition and neural processing. An extreme reduction is the removal of the very stimulus, defining it with illusory lines. Perceived boundaries without physical differences between shape and background are called illusory (or subjective) contours. Illusory and real contours activate early stages of the macaque visual pathway in similar ways. However, data relating to the processing of illusory contours in higher visual areas are scarce. We recently reported how illusory contours based on abutting-line gratings affect neurones in the monkey inferotemporal cortex, an area essential for object and shape vision. We now present data on how inferotemporal cortical neurones of monkeys react to another type of shapes, the Kanizsa figures. A set of line drawings, silhouettes, their illusory contour-based counterparts, and control shapes have been presented to awake, fixating rhesus monkeys while single-cell activity was recorded in the anterior part of the inferotemporal cortex. Most of the recorded neurones were responsive and selective to shapes presented as illusory contours. Shape selectivity was proved to be different for line drawings and illusory contours, and also for silhouettes and illusory contours. Neuronal response latencies for Kanizsa figures were significantly longer than those for line drawings and silhouettes. These results reveal differences in processing for Kanizsa figures and shapes having real contours in the monkey inferotemporal cortex. [source] Coherent state path integral and super-symmetry for condensates composed of bosonic and fermionic atomsFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 9-10 2007B. Mieck Abstract A super-symmetric coherent state path integral on the Keldysh time contour is considered for bosonic and fermionic atoms which interact among each other with a common short-ranged two-body potential. We investigate the symmetries of Bose-Einstein condensation for the equivalent bosonic and fermionic constituents with the same interaction potential so that a super-symmetry results between the bosonic and fermionic components of super-fields. Apart from the super-unitary invariance U(L | S) of the density terms, we specialize on the examination of super-symmetries for pair condensate terms. Effective equations are derived for anomalous terms which are related to the molecular- and BCS- condensate pairs. A Hubbard-Stratonovich transformation from ,Nambu'-doubled super-fields leads to a generating function with super-matrices for the self-energy whose manifold is given by the orthosympletic super-group Osp(S,S | 2L). A nonlinear sigma model follows from the spontaneous breaking of the ortho-symplectic super-group Osp(S,S | 2L) to the coset decomposition Osp(S,S | 2L) \ U(L | S), U(L | S). The invariant subgroup U(L | S) for the vacuum or background fields is represented by the density terms in the self-energy whereas the super-matrices on the coset space Osp(S,S | 2L) \ U(L | S) describe the anomalous molecular and BCS- pair condensate terms. A change of integration measure is performed for the coset decomposition Osp(S,S | 2L) \ U(L | S) , U(L | S), including a separation of density and anomalous parts of the self-energy with a gradient expansion for the Goldstone modes. The independent anomalous fields in the actions can be transformed by the inverse square root of the metric tensor of Osp(S,S | 2L) \ U(L | S) so that the non-Euclidean integration measure with super-Jacobi-determinant can be removed from the coherent state path integral and Gaussian-like integrations remain. The variations of the independent coset fields in the effective actions result in classical field equations for a nonlinear sigma model with the anomalous terms. The dynamics of the eigenvalues of the coset matrices is determined by Sine-Gordon equations which have a similar meaning for the dynamics of the molecular- and BCS-pair condensates as the Gross-Pitaevskii equation for the coherent wave function in BEC phenomena. [source] |