A novel model-based evolutionary algorithm for multi-objective deformable image registration with content mismatch and large deformations: benchmarking efficiency and quality

NASA Astrophysics Data System (ADS)

Bouter, Anton; Alderliesten, Tanja; Bosman, Peter A. N.

2017-02-01

Taking a multi-objective optimization approach to deformable image registration has recently gained attention, because such an approach removes the requirement of manually tuning the weights of all the involved objectives. Especially for problems that require large complex deformations, this is a non-trivial task. From the resulting Pareto set of solutions one can then much more insightfully select a registration outcome that is most suitable for the problem at hand. To serve as an internal optimization engine, currently used multi-objective algorithms are competent, but rather inefficient. In this paper we largely improve upon this by introducing a multi-objective real-valued adaptation of the recently introduced Gene-pool Optimal Mixing Evolutionary Algorithm (GOMEA) for discrete optimization. In this work, GOMEA is tailored specifically to the problem of deformable image registration to obtain substantially improved efficiency. This improvement is achieved by exploiting a key strength of GOMEA: iteratively improving small parts of solutions, allowing to faster exploit the impact of such updates on the objectives at hand through partial evaluations. We performed experiments on three registration problems. In particular, an artificial problem containing a disappearing structure, a pair of pre- and post-operative breast CT scans, and a pair of breast MRI scans acquired in prone and supine position were considered. Results show that compared to the previously used evolutionary algorithm, GOMEA obtains a speed-up of up to a factor of 1600 on the tested registration problems while achieving registration outcomes of similar quality.

Outcome analysis, including patient and parental satisfaction, regarding nonvascularized free toe phalanx transfer in congenital hand deformities.

PubMed

Unglaub, F; Lanz, U; Hahn, P

2006-01-01

The therapy for congenital hand malformations, especially in symbrachydactyly and constriction ring syndromes, is challenging. Between 1975 and 1995, 20 children with congenital hand deformities underwent reconstruction by 56 nonvascularized free toe phalanx transfers. The average age at initial surgery was 4.8 (range, 0.5 to 22) years. Retrospectively, the children were examined after an average of 3.5 (range, 1.5 to 17.6) years for function of the hand, transplanted phalanx growth, assessment for the epiphyseal plate, and assessment for psychologic performance with their parents. Donor-site morbidity was determined according to measured growth deficit, observing the child's gait, and toe function. In the younger patients (up to 1.5 years), the grafts were well tolerated and showed good growth and only few resorptions. In the age group from 1.5 to 4 years, the grafts showed no growth. In the age group older than 4 years, the grafts were mostly resorbed. The clinical reexamination revealed in most cases only passive motion in the joints, but the function of the hand was improved, with only few problems of the donor site. Most patients and their parents reported a positive effect of the phalanx transfer.

[Hand management in recessive dystrophic bullous epydermolysis].

PubMed

Pajardi, G; Novelli, C; Parolo, C; Proserpio, G; Tegon, M; Vecchi, S

2011-01-01

Recessive distrofic epidermolysis bullosa creates severe hand deformities with disabling functional limitations. Hand surgeon should perform surgery when deformity inibits function, in order to restore the pinch. We present our experience on 44 patients and 58 operated hands, with the following schema: hand degloving, grafting of the first web and intraoperative dynamic splinting. In 30 patient with an 8 years follow up, 25 had had good or excellent results, and the 5 remaining shows early recurrence. Association of a correct surgical approach and adequate intra and post-operative rehabilitation improve hand function and a slow down inevitable recurrence.

Hand-Held Volatilome Analyzer Based on Elastically Deformable Nanofibers.

PubMed

Yucel, Muge; Akin, Osman; Cayoren, Mehmet; Akduman, Ibrahim; Palaniappan, Alagappan; Liedberg, Bo; Hizal, Gurkan; Inci, Fatih; Yildiz, Umit Hakan

2018-04-17

This study reports on a hand-held volatilome analyzer for selective determination of clinically relevant biomarkers in exhaled breath. The sensing platform is based on electrospun polymer nanofiber-multiwalled carbon nanotube (MWCNT) sensing microchannels. Polymer nanofibers of poly(vinylidene fluoride) (PVDF), polystyrene (PS), and poly(methyl methacrylate) (PMMA) incorporated with MWCNT exhibits a stable response to interferences of humidity and CO 2 and provides selective deformations upon exposure of exhaled breath target volatilomes acetone and toluene, exhibiting correlation to diabetes and lung cancer, respectively. The sensing microchannels "P1" (PVDF-MWCNT), "P2" (PS-MWCNT), and "P3" (PMMA-MWCNT) are integrated with a microfluidic cartridge (μ-card) that facilitates collection and concentration of exhaled breath. The volatilome analyzer consists of a conductivity monitoring unit, signal conditioning circuitries and a low energy display module. A combinatorial operation algorithm was developed for analyzing normalized resistivity changes of the sensing microchannels upon exposure to breath in the concentration ranges between 35 ppb and 3.0 ppm for acetone and 1 ppb and 10 ppm for toluene. Subsequently, responses of volatilomes from individuals in the different risk groups of diabetes were evaluated for validation of the proposed methodology. We foresee that proposed methodology provides an avenue for rapid detection of volatilomes thereby enabling point of care diagnosis in high-risk group individuals.

Evaluation of fingerprint deformation using optical coherence tomography

NASA Astrophysics Data System (ADS)

Gutierrez da Costa, Henrique S.; Maxey, Jessica R.; Silva, Luciano; Ellerbee, Audrey K.

2014-02-01

Biometric identification systems have important applications to privacy and security. The most widely used of these, print identification, is based on imaging patterns present in the fingers, hands and feet that are formed by the ridges, valleys and pores of the skin. Most modern print sensors acquire images of the finger when pressed against a sensor surface. Unfortunately, this pressure may result in deformations, characterized by changes in the sizes and relative distances of the print patterns, and such changes have been shown to negatively affect the performance of fingerprint identification algorithms. Optical coherence tomography (OCT) is a novel imaging technique that is capable of imaging the subsurface of biological tissue. Hence, OCT may be used to obtain images of subdermal skin structures from which one can extract an internal fingerprint. The internal fingerprint is very similar in structure to the commonly used external fingerprint and is of increasing interest in investigations of identify fraud. We proposed and tested metrics based on measurements calculated from external and internal fingerprints to evaluate the amount of deformation of the skin. Such metrics were used to test hypotheses about the differences of deformation between the internal and external images, variations with the type of finger and location inside the fingerprint.

Customized silicone implant for the correction of acquired and congenital chest wall deformities: A valuable option with pectus excavatum.

PubMed

Soccorso, Giampiero; Parikh, Dakshesh H; Worrollo, Steve

2015-07-01

Surgical remodeling and correction of congenital and acquired chest wall deformities (CWD) is undertaken many times for cosmesis. Although reportedly minimally invasive, commonly used Nuss procedure for correction of pectus excavatum (PE) is not without complications. Nuss procedure is also not suitable for complex deformities and Poland syndrome cases. Insertion of custom-made silicone implants for the reconstruction of defects has been adopted from adult plastic reconstructive surgery as primary repair of CWD or rescue procedure for recurrence of PE after recurrence or residual deformity. We present our experience with CWD reconstruction in children with customized silicone prosthesis made from a surgically implantable liquid silicone rubber (NuSil MED-4805, Ca). Since 2006 we treated 26 patients with CWD: six were children (age <17years, median 14.6) with PE. Implants were custom made for each patient's chest. The implants were inserted under general anesthesia. Postoperatively all patients were fully satisfied with the cosmetic result and subjective patient satisfaction remained excellent at follow-up in all the children. Only one child developed postoperative complications (seroma). Customized silicone implant for PE in the pediatric age is an alternative therapeutic method, as primary or rescue treatment, with equally good cosmetic outcome, fewer significant complications, less postoperative pain and a faster recovery. Copyright © 2015 Elsevier Inc. All rights reserved.

The Intersection between Ocular and Manual Motor Control: Eye–Hand Coordination in Acquired Brain Injury

PubMed Central

Rizzo, John-Ross; Hosseini, Maryam; Wong, Eric A.; Mackey, Wayne E.; Fung, James K.; Ahdoot, Edmond; Rucker, Janet C.; Raghavan, Preeti; Landy, Michael S.; Hudson, Todd E.

2017-01-01

Acute and chronic disease processes that lead to cerebral injury can often be clinically challenging diagnostically, prognostically, and therapeutically. Neurodegenerative processes are one such elusive diagnostic group, given their often diffuse and indolent nature, creating difficulties in pinpointing specific structural abnormalities that relate to functional limitations. A number of studies in recent years have focused on eye–hand coordination (EHC) in the setting of acquired brain injury (ABI), highlighting the important set of interconnected functions of the eye and hand and their relevance in neurological conditions. These experiments, which have concentrated on focal lesion-based models, have significantly improved our understanding of neurophysiology and underscored the sensitivity of biomarkers in acute and chronic neurological disease processes, especially when such biomarkers are combined synergistically. To better understand EHC and its connection with ABI, there is a need to clarify its definition and to delineate its neuroanatomical and computational underpinnings. Successful EHC relies on the complex feedback- and prediction-mediated relationship between the visual, ocular motor, and manual motor systems and takes advantage of finely orchestrated synergies between these systems in both the spatial and temporal domains. Interactions of this type are representative of functional sensorimotor control, and their disruption constitutes one of the most frequent deficits secondary to brain injury. The present review describes the visually mediated planning and control of eye movements, hand movements, and their coordination, with a particular focus on deficits that occur following neurovascular, neurotraumatic, and neurodegenerative conditions. Following this review, we also discuss potential future research directions, highlighting objective EHC as a sensitive biomarker complement within acute and chronic neurological disease processes. PMID:28620341

Choosing a Hand-Held Inventory Device

ERIC Educational Resources Information Center

Green, Lois; Hughes, Janet; Neff, Verne; Notartomas, Trish

2008-01-01

In spring of 2006, a task force was charged to look at the feasibility of acquiring hand-held inventory devices for the Pennsylvania State University Libraries (PSUL). The task force's charge was not to look at the whole concept of doing an inventory, but rather to focus on the feasibility of acquiring hand-held devices to use in an inventory.…

Outcomes of a Stepcut Lengthening Calcaneal Osteotomy for Adult-Acquired Flatfoot Deformity.

PubMed

Demetracopoulos, Constantine A; Nair, Pallavi; Malzberg, Andrew; Deland, Jonathan T

2015-07-01

Lateral column lengthening is used to correct abduction deformity at the midfoot and improve talar head coverage in patients with flatfoot deformity. It was our hypothesis that following a stepcut lengthening calcaneal osteotomy (SLCO), patients would have adequate correction of the deformity, a high union rate of the osteotomy, and improvement in clinical outcome scores. We retrospectively reviewed 37 consecutive patients who underwent SLCO for the treatment of stage IIB flatfoot deformity with a minimum 2-year follow-up. Deformity correction was assessed using preoperative and postoperative weight-bearing radiographs. Healing of the osteotomy was assessed by computed tomography. Clinical outcomes included the FAOS and SF-36 questionnaires. The Wilcoxon signed-rank test was used to compare clinical outcome scores. An alpha level of .05 was deemed statistically significant. Healing of the osteotomy occurred at a mean of 7.7 weeks postoperatively. The talonavicular (TN) coverage angle improved from 34.0 to 8.8 (P < .001), the percentage of TN uncoverage improved from 40.9% to 17.7% (P < .001), and the TN incongruency angle improved from 68.1 to 8.7 (P < .001). In addition, there was an improvement in FAOS pain (P < .001), daily activities (P < .001), sport activities (P = .006), and quality of life scores (P < .001). Overall SF-36 scores also showed improvement postoperatively (P < .001). There was no incidence of delayed union, nonunion, or graft collapse. Following SLCO, patients demonstrated excellent healing, good correction of the deformity, and improvement in clinical outcomes scores. The SLCO is an alternative to the Evans osteotomy for lateral column lengthening. Level IV, retrospective case review. © The Author(s) 2015.

Thumb in the plane of the hand: characterization and results of surgical treatment.

PubMed

Langer, Jakub S; Manske, Paul R; Steffen, Jennifer A; Hu, Calvin; Goldfarb, Charles

2009-12-01

The purpose of this retrospective investigation is to characterize a congenital deformity, the thumb in the plane of the hand (TPH), and to evaluate the results of abduction-rotation osteotomy of the thumb metacarpal with thumb web space deepening (WSD). We performed a comprehensive analysis of the medical records, hand therapy notes, and radiographs to evaluate clinical features of the TPH deformity. We evaluated clinical and radiographic outcomes and incidence of deformity recurrence after abduction-rotation osteotomy and thumb WSD. Thirteen patients (7 girls and 6 boys) with 14 affected hands treated with an abduction-rotation osteotomy of the thumb metacarpal and formation of a deepened thumb-index web space met inclusion criteria. All TPH deformities were associated with other congenital conditions, including symbrachydactyly, syndactyly, central deficiency, and ulnar deficiency. During the course of treatment, patients had a mean of 4 surgeries per hand; 3 hands required osteotomy revision with or without revision WSD, and 6 additional hands required revision of thumb WSD alone. None of the affected hands were capable of thumb opposition to any finger before surgery, whereas after surgery, all 14 hands could actively perform key pinch, and 9 of the 14 hands could actively oppose the thumb to at least 1 finger. The TPH deformity occurs in association with other congenital abnormalities of the hand. An abduction-rotation osteotomy of the thumb metacarpal with thumb WSD can restore thumb opposition and improve function; nonetheless, multiple surgical procedures are often required, and thumb function may remain limited. Therapeutic IV.

Hand biometric recognition based on fused hand geometry and vascular patterns.

PubMed

Park, GiTae; Kim, Soowon

2013-02-28

A hand biometric authentication method based on measurements of the user's hand geometry and vascular pattern is proposed. To acquire the hand geometry, the thickness of the side view of the hand, the K-curvature with a hand-shaped chain code, the lengths and angles of the finger valleys, and the lengths and profiles of the fingers were used, and for the vascular pattern, the direction-based vascular-pattern extraction method was used, and thus, a new multimodal biometric approach is proposed. The proposed multimodal biometric system uses only one image to extract the feature points. This system can be configured for low-cost devices. Our multimodal biometric-approach hand-geometry (the side view of the hand and the back of hand) and vascular-pattern recognition method performs at the score level. The results of our study showed that the equal error rate of the proposed system was 0.06%.

Amniotic Constriction Bands: Secondary Deformities and Their Treatments.

PubMed

Drury, Benjamin T; Rayan, Ghazi M

2018-01-01

The purpose of this study was to report the surgical treatment experience of patients with amniotic constriction bands (ACB) over a 35-year interval and detail consequential limb deformities with emphasis on hands and upper extremities, along with the nature and frequency of their surgical treatment methods. Fifty-one patients were identified; 26 were males and 25 females. The total number of deformities was listed. The total number of operations, individual procedures, and operations plus procedures that were done for each patient and their frequency were recorded. The total number of operations was 117, and total number of procedures was 341. More procedures were performed on the upper extremity (85%) than the lower extremity (15%). Including the primary deformity ACB, 16 different hand deformities secondary to ACB were encountered. Sixteen different surgical methods for the upper extremity were utilized; a primary procedure for ACB and secondary reconstructions for all secondary deformities. Average age at the time of the first procedure was 9.3 months. The most common procedures performed, in order of frequency, were excision of ACB plus Z-plasty, release of partial syndactyly, release of fenestrated syndactyly, full-thickness skin grafts, resection of digital bony overgrowth from amputation stumps, and deepening of first and other digital web spaces. Many hand and upper extremity deformities secondary to ACB are encountered. Children with ACB may require more than one operation including multiple procedures. Numerous surgical methods of reconstruction for these children's secondary deformities are necessary in addition to the customary primary procedure of excision of ACB and Z-plasty.

Unilateral Cleft Hand with Cleft Foot

PubMed Central

Baba, Asif Nazir; Bhat, Yasmeen J.; Ahmed, Sheikh Mushtaq; Nazir, Abid

2009-01-01

Congenital anomalies of the hand form an important class of congenital malformations. They have a huge functional importance because of the part played by the hand in the daily activities of a person. The deformities also have significant cosmetic significance and may also be associated with other anomalies. Amongst the congenital anomalies, central deficiency or cleft hand is relatively rare. The association of cleft foot with cleft hand is an even more rare occurance. We present a case report of a 6 year old child, born of a non-consanginous marriage, having congenital central deficiency of ipsilateral hand and foot. PMID:21475543

Hand Biometric Recognition Based on Fused Hand Geometry and Vascular Patterns

PubMed Central

Park, GiTae; Kim, Soowon

2013-01-01

A hand biometric authentication method based on measurements of the user's hand geometry and vascular pattern is proposed. To acquire the hand geometry, the thickness of the side view of the hand, the K-curvature with a hand-shaped chain code, the lengths and angles of the finger valleys, and the lengths and profiles of the fingers were used, and for the vascular pattern, the direction-based vascular-pattern extraction method was used, and thus, a new multimodal biometric approach is proposed. The proposed multimodal biometric system uses only one image to extract the feature points. This system can be configured for low-cost devices. Our multimodal biometric-approach hand-geometry (the side view of the hand and the back of hand) and vascular-pattern recognition method performs at the score level. The results of our study showed that the equal error rate of the proposed system was 0.06%. PMID:23449119

A helping hand for infection control.

PubMed

Allen, Mike

2004-09-01

Despite considerable awareness amongst the healthcare community about the importance of hand hygiene in controlling Healthcare Acquired Infections (HAIs), the problem persists. Mike Allen of Dart Valley Systems explores the issues surrounding good hand hygiene practice in UK hospitals.

Digital fringe projection for hand surface coordinate variation analysis caused by osteoarthritis

NASA Astrophysics Data System (ADS)

Nor Haimi, Wan Mokhdzani Wan; Hau Tan, Cheek; Retnasamy, Vithyacharan; Vairavan, Rajendaran; Sauli, Zaliman; Roshidah Yusof, Nor; Hambali, Nor Azura Malini Ahmad; Aziz, Muhammad Hafiz Ab; Bakhit, Ahmad Syahir Ahmad

2017-11-01

Hand osteoarthritis is one of the most common forms of arthritis which impact millions of people worldwide. The disabling problem occurs when the protective cartilage on the boundaries of bones wear off over time. Currently, in order to identify hand osteoarthritis, special instruments namely X-ray scanning and MRI are used for the detection but it also has its limitations such as radiation exposure and can be quite costly. In this work, an optical metrology system based on digital fringe projection which comprises of an LCD projector, CCD camera and a personal computer has been developed to anticipate abnormal growth or deformation on the joints of the hand which are common symptoms of osteoarthritis. The main concept of this optical metrology system is to apply structured light as imaging source for surface change detection. The imaging source utilizes fringe patterns generated by C++ programming and is shifted by 3 phase shifts based on the 3 steps 2 shifts method. Phase wrapping technique and analysis were applied in order to detect the deformation of live subjects. The result has demonstrated a successful method of hand deformation detection based on the pixel tracking differences of a normal and deformed state.

Formation of social and household skills in children with hand defects.

PubMed

Klimon, Nataly; Koryukov, Alexander; Loseva, Nina; Starobina, Elena

2015-08-01

The aim of this study was to consider the peculiarities of forming social and household skills, and the criteria for their evaluation, as well as an assessment of functional capacity, in children with hand defects both before and after surgical treatment and rehabilitation courses using a system of games. We elaborated and implemented a program of social rehabilitation of preschool children with congenital and acquired hand defects for the development of their functional capabilities and the formation of social and household skills after surgical treatment and prosthetics using play therapy methods. As part of this work, 140 preschool children aged 3-7 years underwent social rehabilitation. Most of the children had congenital hand defects-122 children (87 %): 96 children (79 %) with ectrodactylia, adactylia, hypoplasia, aplasia, hand splitting, club hand, or partial gigantism; 26 children (21 %) with congenital syndactylism and constricted bonds and 18 children (13 %) with acquired defects (burn deformity, amputation). 110 children (79 %) had reached the stage of surgical correction; 30 children (21 %) reached the stage of prosthetics. Most of the children participating in the experiment (78 children, 56 %) had defects of fingers on one hand. The program aimed at solving specific rehabilitation tasks: formation and improvement of all possible types of grip under the existing defect including those after surgery and prosthetics; development of tactile sensations in fingers; development of fine motor skills; increase in range of motion in all joints of the damaged hand; development of attention and concentration; formation of social and household skills appropriate to age; and development of the ability to achieve the set task. Analysis of the level of social and household skills of children with hand defects undergoing rehabilitation treatment at the hospital depending on the age prior to medical and social rehabilitation showed that preschool children with

Texture- and deformability-based surface recognition by tactile image analysis.

PubMed

Khasnobish, Anwesha; Pal, Monalisa; Tibarewala, D N; Konar, Amit; Pal, Kunal

2016-08-01

Deformability and texture are two unique object characteristics which are essential for appropriate surface recognition by tactile exploration. Tactile sensation is required to be incorporated in artificial arms for rehabilitative and other human-computer interface applications to achieve efficient and human-like manoeuvring. To accomplish the same, surface recognition by tactile data analysis is one of the prerequisites. The aim of this work is to develop effective technique for identification of various surfaces based on deformability and texture by analysing tactile images which are obtained during dynamic exploration of the item by artificial arms whose gripper is fitted with tactile sensors. Tactile data have been acquired, while human beings as well as a robot hand fitted with tactile sensors explored the objects. The tactile images are pre-processed, and relevant features are extracted from the tactile images. These features are provided as input to the variants of support vector machine (SVM), linear discriminant analysis and k-nearest neighbour (kNN) for classification. Based on deformability, six household surfaces are recognized from their corresponding tactile images. Moreover, based on texture five surfaces of daily use are classified. The method adopted in the former two cases has also been applied for deformability- and texture-based recognition of four biomembranes, i.e. membranes prepared from biomaterials which can be used for various applications such as drug delivery and implants. Linear SVM performed best for recognizing surface deformability with an accuracy of 83 % in 82.60 ms, whereas kNN classifier recognizes surfaces of daily use having different textures with an accuracy of 89 % in 54.25 ms and SVM with radial basis function kernel recognizes biomembranes with an accuracy of 78 % in 53.35 ms. The classifiers are observed to generalize well on the unseen test datasets with very high performance to achieve efficient material

Deformation Measurements of Smart Aerodynamic Surfaces

NASA Technical Reports Server (NTRS)

Fleming, Gary A.; Burner, Alpheus

2005-01-01

Video Model Deformation (VMD) and Projection Moire Interferometry (PMI) were used to acquire wind tunnel model deformation measurements of the Northrop Grumman-built Smart Wing tested in the NASA Langley Transonic Dynamics Tunnel. The F18-E/F planform Smart Wing was outfitted with embedded shape memory alloys to actuate a seamless trailing edge aileron and flap, and an embedded torque tube to generate wing twist. The VMD system was used to obtain highly accurate deformation measurements at three spanwise locations along the main body of the wing, and at spanwise locations on the flap and aileron. The PMI system was used to obtain full-field wing shape and deformation measurements over the entire wing lower surface. Although less accurate than the VMD system, the PMI system revealed deformations occurring between VMD target rows indistinguishable by VMD. This paper presents the VMD and PMI techniques and discusses their application in the Smart Wing test.

Study on Surgical Management of Post Burn Hand Deformities

PubMed Central

Ahmed, Firdos; Jash, Prabir Kumar; Gupta, Madhumita; Suba, Santanu

2015-01-01

Context Functionality of the hands is the major determinants of the quality of life in burns survivors. If contractures or scarring affect the dominant hand, as they do on most occasions, the vocation and there by the economic status of the patient suffer. Aim The aim of this study is to evaluate the different surgical procedures for resurfacing after release of post-burn hand contractures in terms of functional recovery and aesthetic outcome. Settings and Design It’s a prospective, non-randomised study of 50 patients admitted and undergoing surgical reconstructive procedures for post burn hand contractures in our plastic surgery department. Materials and Methods Resurfacing procedures were done according to type of contracture with individualisation for each case. All cases were followed up with physiotherapy and splinting advices. Functional and aesthetic outcome and recurrence of contracture for each procedure was noted at 6 months. Results Forty seven percent of the cases were reconstructed with skin grafting, 30% cases with Z plasties and 23% with flap coverage. Split thickness skin grafts (STSG) and full thickness graft (FTSG) reconstructed cases had good recovery of joint mobility in 43% and 75% of cases respectively. Reconstructive procedures were aesthetically acceptable to the patients in 63%, 75% and 94% of STSG, FTSG and Z plasty cases respectively. Recurrence was seen in 17% of STSG done cases. Conclusion Most of the cases can be resurfaced with skin grafting and few cases have clear indication for flap coverage which needs to be planned and executed cautiously. Z plasties with proper planning gives maximum length gain with no donor morbidity as other procedures. Postoperative physiotherapy and splinting is must for better outcome in all cases. PMID:26435994

Evolution of the human hand: approaches to acquiring, analysing and interpreting the anatomical evidence

PubMed Central

MARZKE, MARY W.; MARZKE, R. F.

2000-01-01

The discovery of fossil hand bones from an early human ancestor at Olduvai Gorge in 1960, at the same level as primitive stone tools, generated a debate about the role of tools in the evolution of the human hand that has raged to the present day. Could the Olduvai hand have made the tools? Did the human hand evolve as an adaptation to tool making and tool use? The debate has been fueled by anatomical studies comparing living and fossil human and nonhuman primate hands, and by experimental observations. These have assessed the relative abilities of apes and humans to manufacture the Oldowan tools, but consensus has been hampered by disagreements about how to translate experimental data from living species into quantitative models for predicting the performance of fossil hands. Such models are now beginning to take shape as new techniques are applied to the capture, management and analysis of data on kinetic and kinematic variables ranging from hand joint structure, muscle mechanics, and the distribution and density of bone to joint movements and muscle recruitment during manipulative behaviour. The systematic comparative studies are highlighting a functional complex of features in the human hand facilitating a distinctive repertoire of grips that are apparently more effective for stone tool making than grips characterising various nonhuman primate species. The new techniques are identifying skeletal variables whose form may provide clues to the potential of fossil hominid hands for one-handed firm precision grips and fine precision manoeuvering movements, both of which are essential for habitual and effective tool making and tool use. PMID:10999274

Comparative Outcomes Between Step-Cut Lengthening Calcaneal Osteotomy vs Traditional Evans Osteotomy for Stage IIB Adult-Acquired Flatfoot Deformity.

PubMed

Saunders, Stuart M; Ellis, Scott J; Demetracopoulos, Constantine A; Marinescu, Anca; Burkett, Jayme; Deland, Jonathan T

2018-01-01

The forefoot abduction component of the flexible adult-acquired flatfoot can be addressed with lengthening of the anterior process of the calcaneus. We hypothesized that the step-cut lengthening calcaneal osteotomy (SLCO) would decrease the incidence of nonunion, lead to improvement in clinical outcome scores, and have a faster time to healing compared with the traditional Evans osteotomy. We retrospectively reviewed 111 patients (143 total feet: 65 Evans, 78 SLCO) undergoing stage IIB reconstruction followed clinically for at least 2 years. Preoperative and postoperative radiographs were analyzed for the amount of deformity correction. Computed tomography (CT) was used to analyze osteotomy healing. The Foot and Ankle Outcome Scores (FAOS) and lateral pain surveys were used to assess clinical outcomes. Mann-Whitney U tests were used to assess nonnormally distributed data while χ 2 and Fisher exact tests were used to analyze categorical variables (α = 0.05 significant). The Evans group used a larger graft size ( P < .001) and returned more often for hardware removal ( P = .038) than the SLCO group. SLCO union occurred at a mean of 8.77 weeks ( P < .001), which was significantly lower compared with the Evans group ( P = .02). The SLCO group also had fewer nonunions ( P = .016). FAOS scores improved equivalently between the 2 groups. Lateral column pain, ability to exercise, and ambulation distance were similar between groups. Following SLCO, patients had faster healing times and fewer nonunions, similar outcomes scores, and equivalent correction of deformity. SLCO is a viable technique for lateral column lengthening. Level III, retrospective cohort study.

Iterative co-creation for improved hand hygiene and aseptic techniques in the operating room: experiences from the safe hands study.

PubMed

Erichsen Andersson, Annette; Frödin, Maria; Dellenborg, Lisen; Wallin, Lars; Hök, Jesper; Gillespie, Brigid M; Wikström, Ewa

2018-01-04

Hand hygiene and aseptic techniques are essential preventives in combating hospital-acquired infections. However, implementation of these strategies in the operating room remains suboptimal. There is a paucity of intervention studies providing detailed information on effective methods for change. This study aimed to evaluate the process of implementing a theory-driven knowledge translation program for improved use of hand hygiene and aseptic techniques in the operating room. The study was set in an operating department of a university hospital. The intervention was underpinned by theories on organizational learning, culture and person centeredness. Qualitative process data were collected via participant observations and analyzed using a thematic approach. Doubts that hand-hygiene practices are effective in preventing hospital acquired infections, strong boundaries and distrust between professional groups and a lack of psychological safety were identified as barriers towards change. Facilitated interprofessional dialogue and learning in "safe spaces" worked as mechanisms for motivation and engagement. Allowing for the free expression of different opinions, doubts and viewing resistance as a natural part of any change was effective in engaging all professional categories in co-creation of clinical relevant solutions to improve hand hygiene. Enabling nurses and physicians to think and talk differently about hospital acquired infections and hand hygiene requires a shift from the concept of one-way directed compliance towards change and learning as the result of a participatory and meaning-making process. The present study is a part of the Safe Hands project, and is registered with ClinicalTrials.gov (ID: NCT02983136 ). Date of registration 2016/11/28, retrospectively registered.

High-Efficiency Multiscale Modeling of Cell Deformations in Confined Microenvironments in Microcirculation and Microfluidic Devices

NASA Astrophysics Data System (ADS)

Lu, Huijie; Peng, Zhangli

2017-11-01

Our goal is to develop a high-efficiency multiscale modeling method to predict the stress and deformation of cells during the interactions with their microenvironments in microcirculation and microfluidic devices, including red blood cells (RBCs) and circulating tumor cells (CTCs). There are more than 1 billion people in the world suffering from RBC diseases, e.g. anemia, sickle cell diseases, and malaria. The mechanical properties of RBCs are changed in these diseases due to molecular structure alternations, which is not only important for understanding the disease pathology but also provides an opportunity for diagnostics. On the other hand, the mechanical properties of cancer cells are also altered compared to healthy cells. This can lead to acquired ability to cross the narrow capillary networks and endothelial gaps, which is crucial for metastasis, the leading cause of cancer mortality. Therefore, it is important to predict the deformation and stress of RBCs and CTCs in microcirculations. We are developing a high-efficiency multiscale model of cell-fluid interaction to study these two topics.

Prevalence of self-reported finger deformations and occupational risk factors among professional cooks: a cross-sectional study.

PubMed

Nagasu, Miwako; Sakai, Kazuhiro; Kogi, Kazutaka; Ito, Akiyoshi; Feskens, Edith J M; Tomita, Shigeru; Temmyo, Yoshiomi; Ueno, Mitsuo; Miyagi, Shigeji

2011-05-26

Previous studies have pointed out that the school lunch workers in Japan are suffering from work-related disorders including finger deformations. The purpose of this study was to investigate the prevalence of self-reported finger deformations and the association with job-related risk factors. A cross-sectional questionnaire study of 5,719 subjects (response rate: 81%, 982 men and 4,737 women) was undertaken during September 2003 to February 2004. Finger deformations were found among 11.7% of the men and 35.6% of the women studied, with significant differences among sex, age and sex-age groups. For both men and women the pattern of finger deformations across the hand was similar for the right and the left hand. For women, the deformations were found in about 10% of the distal interphalangeal joints of all fingers. Based on multiple logistic regression analyses, the factors female sex, age, the number of cooked lunches per cook and cooking activities were independently associated with the prevalence of finger deformations. High prevalence odds ratios were found for those frequently carrying or using tools by hands such as delivering containers, distributing meals, preparing dishes, washing equipment, cutting and stirring foods. Among the school lunch workers studied, women had a higher prevalence of finger deformations on all joints of both hands. Various cooking tasks were associated with the prevalence of finger deformations. The results suggest that improvements in working conditions are important for preventing work-related disorders such as finger deformations.

Deformed Palmprint Matching Based on Stable Regions.

PubMed

Wu, Xiangqian; Zhao, Qiushi

2015-12-01

Palmprint recognition (PR) is an effective technology for personal recognition. A main problem, which deteriorates the performance of PR, is the deformations of palmprint images. This problem becomes more severe on contactless occasions, in which images are acquired without any guiding mechanisms, and hence critically limits the applications of PR. To solve the deformation problems, in this paper, a model for non-linearly deformed palmprint matching is derived by approximating non-linear deformed palmprint images with piecewise-linear deformed stable regions. Based on this model, a novel approach for deformed palmprint matching, named key point-based block growing (KPBG), is proposed. In KPBG, an iterative M-estimator sample consensus algorithm based on scale invariant feature transform features is devised to compute piecewise-linear transformations to approximate the non-linear deformations of palmprints, and then, the stable regions complying with the linear transformations are decided using a block growing algorithm. Palmprint feature extraction and matching are performed over these stable regions to compute matching scores for decision. Experiments on several public palmprint databases show that the proposed models and the KPBG approach can effectively solve the deformation problem in palmprint verification and outperform the state-of-the-art methods.

Toe-to-hand transfer.

PubMed

Yoshimura, M

1980-07-01

Toe-to-hand transfer was performed in 28 patients, involving 33 fingers, using microvascular technique. Of this number, 26 patients (31 fingers) had experienced trauma, and the remaining 2 patients (2 fingers) had a congenital deformity. The toew used for grafting were the great toe (1), the second tow (30), and third toe (2). Success was achieved in all cases, sensory recovery was good, and remarkable improvement was attained in function and cosmetic appearance. Metacarpal hand, amputation of thumb, and amputation thumb and three fingers were good indications for this procedure, which gave satisfactory aesthetic results, even in patients with amputation of single digits.

ACQUIRED PES CAVUS IN CHARCOT-MARIE-TOOTH DISEASE.

PubMed

Maranho, Daniel Augusto; Volpon, José Batista

2009-01-01

Hereditary motor and sensory neuropathies, especially Charcot-Marie-Tooth disease, are frequently expressed with an acquired cavusvarus foot which is characterized by a fixed increase of the plantar arch and hindfoot inversion. Diagnosis of the underlying condition achieved through careful patient assessment and local evaluations is the keystone for decision-making about the adequate treatment. The cavus may present as an isolated deformity of the forefoot, hindfoot or it may be a combination of both locations. Related deformities, mainly the varus and toe clawing require appropriate evaluation; clinical characteristics such as severity of the deformity, impairment of the muscular power, flexibility and patient's age are important characteristics in the treatment decision. Conservative treatment of the cavusvarus foot with physiotherapy, insoles and shoe modifications are reserved to young patients and mild deformities. However, there is a tendency of the deformity to become more severe over time because of the progressive feature of the underlying neurological condition. So, the surgical treatment by using classical techniques is performed in early stages. Most importantly is the identification of the primary and main components of each deformity to properly correct them, if possible. Muscular transfers are used to treat the dynamic unbalance, retracted structures should be either divided or lengthened and localized osteotomies should be preferred over arthrodeses, which are reserved for stiff and severely deformed feet in adults.

SU-E-J-104: Evaluation of Accuracy for Various Deformable Image Registrations with Virtual Deformation QA Software

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, S; Kim, K; Kim, M

Purpose: The accuracy of deformable image registration (DIR) has a significant dosimetric impact in radiation treatment planning. We evaluated accuracy of various DIR algorithms using virtual deformation QA software (ImSimQA, Oncology System Limited, UK). Methods: The reference image (Iref) and volume (Vref) was first generated with IMSIMQA software. We deformed Iref with axial movement of deformation point and Vref depending on the type of deformation that are the deformation1 is to increase the Vref (relaxation) and the deformation 2 is to decrease the Vref (contraction) .The deformed image (Idef) and volume (Vdef) were inversely deformed to Iref and Vref usingmore » DIR algorithms. As a Result, we acquired deformed image (Iid) and volume (Vid). The DIR algorithms were optical flow (HS, IOF) and demons (MD, FD) of the DIRART. The image similarity evaluation between Iref and Iid was calculated by Normalized Mutual Information (NMI) and Normalized Cross Correlation (NCC). The value of Dice Similarity Coefficient (DSC) was used for evaluation of volume similarity. Results: When moving distance of deformation point was 4 mm, the value of NMI was above 1.81 and NCC was above 0.99 in all DIR algorithms. Since the degree of deformation was increased, the degree of image similarity was decreased. When the Vref increased or decreased about 12%, the difference between Vref and Vid was within ±5% regardless of the type of deformation. The value of DSC was above 0.95 in deformation1 except for the MD algorithm. In case of deformation 2, that of DSC was above 0.95 in all DIR algorithms. Conclusion: The Idef and Vdef have not been completely restored to Iref and Vref and the accuracy of DIR algorithms was different depending on the degree of deformation. Hence, the performance of DIR algorithms should be verified for the desired applications.« less

The swimming of a perfect deforming helix

NASA Astrophysics Data System (ADS)

Koens, Lyndon; Zhang, Hang; Mourran, Ahmed; Lauga, Eric

2017-11-01

Many bacteria rotate helical flagellar filaments in order to swim. When at rest or rotated counter-clockwise these flagella are left handed helices but they undergo polymorphic transformations to right-handed helices when the motor is reversed. These helical deformations themselves can generate motion, with for example Rhodobacter sphaeroides using the polymorphic transformation of the flagellum to generate rotation, or Spiroplasma propagating a change of helix handedness across its body's length to generate forward motion. Recent experiments reported on an artificial helical microswimmer generating motion without a propagating change in handedness. Made of a temperature sensitive gel, these swimmers moved by changing the dimensions of the helix in a non-reciprocal way. Inspired by these results and helix's ubiquitous presence in the bacterial world, we investigate how a deforming helix moves within a viscous fluid. Maintaining a single handedness along its entire length, we discuss how a perfect deforming helix can create a non-reciprocal swimming stroke, identify its principle directions of motion, and calculate the swimming kinematics asymptotically.

The Free-Hand Technique for S2-Alar-Iliac Screw Placement: A Safe and Effective Method for Sacropelvic Fixation in Adult Spinal Deformity.

PubMed

Shillingford, Jamal N; Laratta, Joseph L; Tan, Lee A; Sarpong, Nana O; Lin, James D; Fischer, Charla R; Lehman, Ronald A; Kim, Yongjung J; Lenke, Lawrence G

2018-02-21

Spinopelvic fixation is an integral part of achieving solid fusion across the lumbosacral junction, especially in deformity procedures requiring substantial correction or long-segment constructs. Traditional S2-alar-iliac (S2AI) screw-placement techniques utilize fluoroscopy, increasing operative time and radiation exposure to the patient and surgeon. We describe a novel free-hand technique for S2AI screw placement in patients with adult spinal deformity. We reviewed the records of 45 consecutive patients who underwent spinopelvic fixation performed with use of S2AI screws by the senior surgeon and various fellows or residents over a 12-month period (2015 to 2016). In each case, the S2AI screws were placed utilizing a free-hand technique without fluoroscopic or image guidance. Screw position and accuracy were assessed by intraoperative O-arm imaging and analyzed using 3-dimensional interactive manipulation of computed tomography images. A total of 100 screws were placed, 51 by the senior surgeon and 49 by trainees. The mean patient age was 57.4 ± 12.7 years at the time of surgery; 37 (82.2%) of the patients were female. Preoperative diagnoses included adult idiopathic scoliosis (n = 19), adult degenerative scoliosis (n = 15), flatback syndrome (n = 2), fixed sagittal imbalance (n = 6), and distal junctional kyphosis (n = 3). Five (5%) of the screws were placed with moderate to severe cortical breaches, all of which perforated the pelvis posteriorly, with no clinically notable neurovascular or visceral complications. The breach rate did not differ significantly between the senior surgeon and trainees. The free-hand technique for S2AI screw placement, when performed in a standardized manner, was demonstrated to be safe and reliable in constructs requiring spinopelvic fixation. The accuracy of screw placement relies on visible and palpable anatomic landmarks that obviate the need for intraoperative fluoroscopy or image guidance, potentially reducing operative time

Contactless and pose invariant biometric identification using hand surface.

PubMed

Kanhangad, Vivek; Kumar, Ajay; Zhang, David

2011-05-01

This paper presents a novel approach for hand matching that achieves significantly improved performance even in the presence of large hand pose variations. The proposed method utilizes a 3-D digitizer to simultaneously acquire intensity and range images of the user's hand presented to the system in an arbitrary pose. The approach involves determination of the orientation of the hand in 3-D space followed by pose normalization of the acquired 3-D and 2-D hand images. Multimodal (2-D as well as 3-D) palmprint and hand geometry features, which are simultaneously extracted from the user's pose normalized textured 3-D hand, are used for matching. Individual matching scores are then combined using a new dynamic fusion strategy. Our experimental results on the database of 114 subjects with significant pose variations yielded encouraging results. Consistent (across various hand features considered) performance improvement achieved with the pose correction demonstrates the usefulness of the proposed approach for hand based biometric systems with unconstrained and contact-free imaging. The experimental results also suggest that the dynamic fusion approach employed in this work helps to achieve performance improvement of 60% (in terms of EER) over the case when matching scores are combined using the weighted sum rule.

Advantages and pitfalls of using free-hand sections of frozen needles for three-dimensional analysis of mesophyll by stereology and confocal microscopy

PubMed Central

LHOTÁKOVÁ, Z; ALBRECHTOVÁ, J; JANÁČEK, J; KUBÍNOVÁ, L

2008-01-01

The anatomical structure of mesophyll tissue in the leaf is tightly connected with many physiological processes in plants. One of the most important mesophyll parameters related to photosynthesis is the internal leaf surface area, i.e. the surface area of mesophyll cell walls exposed to intercellular spaces. An efficient design-based stereological method can be applied for estimation of this parameter, using software-randomized virtual fakir test probes in stacks of optical sections acquired by a confocal microscope within thick physical free-hand sections (i.e. acquired using a hand microtome), as we have shown in the case of fresh Norway spruce needles recently. However, for wider practical use in plant ecophysiology, a suitable form of sample storage and other possible technical constraints of this methodology need to be checked. We tested the effect of freezing conifer needles on their anatomical structure as well as the effect of possible deformations due to the cutting of unembedded material by a hand microtome, which can result in distortions of cutting surfaces. In the present study we found a higher proportion of intercellular spaces in mesophyll in regions near to the surface of a physical section, which means that the measurements should be restricted only to the middle region of the optical section series. On the other hand, the proportion of intercellular spaces in mesophyll as well as the internal needle surface density in mesophyll did not show significant difference between fresh and frozen needles; therefore, we conclude that freezing represents a suitable form of storage of sampled material for proposed stereological evaluation. PMID:19017201

Advantages and pitfalls of using free-hand sections of frozen needles for three-dimensional analysis of mesophyll by stereology and confocal microscopy.

PubMed

Lhotáková, Z; Albrechtová, J; Janácek, J; Kubínová, L

2008-10-01

The anatomical structure of mesophyll tissue in the leaf is tightly connected with many physiological processes in plants. One of the most important mesophyll parameters related to photosynthesis is the internal leaf surface area, i.e. the surface area of mesophyll cell walls exposed to intercellular spaces. An efficient design-based stereological method can be applied for estimation of this parameter, using software-randomized virtual fakir test probes in stacks of optical sections acquired by a confocal microscope within thick physical free-hand sections (i.e. acquired using a hand microtome), as we have shown in the case of fresh Norway spruce needles recently. However, for wider practical use in plant ecophysiology, a suitable form of sample storage and other possible technical constraints of this methodology need to be checked. We tested the effect of freezing conifer needles on their anatomical structure as well as the effect of possible deformations due to the cutting of unembedded material by a hand microtome, which can result in distortions of cutting surfaces. In the present study we found a higher proportion of intercellular spaces in mesophyll in regions near to the surface of a physical section, which means that the measurements should be restricted only to the middle region of the optical section series. On the other hand, the proportion of intercellular spaces in mesophyll as well as the internal needle surface density in mesophyll did not show significant difference between fresh and frozen needles; therefore, we conclude that freezing represents a suitable form of storage of sampled material for proposed stereological evaluation.

Back to basics: hand hygiene and isolation

PubMed Central

Lin Huang, G. Khai; Stewardson, Andrew J.; Lindsay Grayson, M.

2014-01-01

Purpose of review Hand hygiene and isolation are basic, but very effective, means of preventing the spread of pathogens in healthcare. Although the principle may be straightforward, this review highlights some of the controversies regarding the implementation and efficacy of these interventions. Recent findings Hand hygiene compliance is an accepted measure of quality and safety in many countries. The evidence for the efficacy of hand hygiene in directly reducing rates of hospital-acquired infections has strengthened in recent years, particularly in terms of reduced rates of staphylococcal sepsis. Defining the key components of effective implementation strategies and the ideal method(s) of assessing hand hygiene compliance are dependent on a range of factors associated with the healthcare system. Although patient isolation continues to be an important strategy, particularly in outbreaks, it also has some limitations and can be associated with negative effects. Recent detailed molecular epidemiology studies of key healthcare-acquired pathogens have questioned the true efficacy of isolation, alone as an effective method for the routine prevention of disease transmission. Summary Hand hygiene and isolation are key components of basic infection control. Recent insights into the benefits, limitations and even adverse effects of these interventions are important for their optimal implementation. PMID:24945613

Lateral column length in adult flatfoot deformity.

PubMed

Kang, Steve; Charlton, Timothy P; Thordarson, David B

2013-03-01

In adult acquired flatfoot deformity, it is unclear whether the lateral column length shortens with progression of the deformity, whether it is short to begin with, or whether it is short at all. To our knowledge, no previous study has examined the lateral column length of patients with adult acquired flatfoot deformity compared to a control population. The purpose of our study was to compare the lateral column length in patients with and without adult acquired flatfoot deformity to see if there was a significant difference. The study was a retrospective radiographic review of 2 foot and ankle fellowship-trained orthopaedic surgeons' patients with adult flatfoot deformity. Our study population consisted of 75 patients, 85 feet (28 male, 57 female) with adult flatfoot deformity with a mean age of 64 (range, 23-93). Our control population consisted of 57 patients and 70 feet (23 male, 47 female) without flatfoot deformity with a mean age of 61 (range, 40-86 years). Weightbearing anteroposterior (AP) and lateral foot radiographs were analyzed for each patient, and the following measurements were made: medial and lateral column lengths, talonavicular uncoverage angle, talus-first metatarsal angle, calcaneal pitch angle, and medial and lateral column heights. An unpaired t test was used to analyze the measurements between the groups. Ten patients' radiographs were remeasured, and correlation coefficients were obtained to assess the reliability of the measuring techniques. For the flatfoot group, the mean medial and lateral column lengths on the AP radiograph were 108.6 mm and 95.8 mm, respectively; the mean talo-navicular uncoverage angle was 26.2 degrees; and the mean talus-first metatarsal angle was 20.0 degrees. In the control group, the mean medial and lateral column lengths on the AP radiograph were 108.8 mm and 96.5 mm, respectively; the mean talo-navicular uncoverage angle was 8.2 degrees; and the mean talus-first metatarsal angle was 7.7 degrees. On the lateral

Rice cooker steam hand burn in the pediatric patient.

PubMed

Roh, T S; Kim, Y S; Burm, J S; Chung, C H; Kim, J B; Oh, S J

2000-07-01

Burn injuries often lead to significant cosmetic and functional deformity. In the Orient, household electric rice cookers have caused a significant number of steam burns to infant hands. The clinical course and treatment outcome of these burns have been studied retrospectively in a review of the medical records of 79 pediatric patients treated for acute hand steam burns and of 38 other patients who underwent correction for postburn contracture. Electric rice cookers caused all of the acute pediatric steam burns treated at our institute. Of the 81 hands treated between 1995 and 1998, 38.3 percent healed with conservative treatment and 61.7 percent required skin grafting. The volar aspects of the index and middle fingers were those most frequently involved. Eighteen of 36 hands (50 percent) grafted with split-thickness skin developed late contractures requiring additional procedures. Among the 38 patients who underwent correction for postburn deformity, initial treatment was split-thickness grafting for 60.5 percent, full-thickness skin grafting for 7.9 percent, and spontaneous healing for 31.6 percent. Awareness among medical personnel and continued public education should be promoted to help prevent this unique type of pediatric steam burn from occurring.

Using postural synergies to animate a low-dimensional hand avatar in haptic simulation.

PubMed

Mulatto, Sara; Formaglio, Alessandro; Malvezzi, Monica; Prattichizzo, Domenico

2013-01-01

A technique to animate a realistic hand avatar with 20 DoFs based on the biomechanics of the human hand is presented. The animation does not use any sensor glove or advanced tracker with markers. The proposed approach is based on the knowledge of a set of kinematic constraints on the model of the hand, referred to as postural synergies, which allows to represent the hand posture using a number of variables lower than the number of joints of the hand model. This low-dimensional set of parameters is estimated from direct measurement of the motion of thumb and index finger tracked using two haptic devices. A kinematic inversion algorithm has been developed, which takes synergies into account and estimates the kinematic configuration of the whole hand, i.e., also of the fingers whose end tips are not directly tracked by the two haptic devices. The hand skin is deformable and its deformation is computed using a linear vertex blending technique. The proposed synergy-based animation of the hand avatar involves only algebraic computations and is suitable for real-time implementation as required in haptics.

Hand hygiene noncompliance and the cost of hospital-acquired methicillin-resistant Staphylococcus aureus infection.

PubMed

Cummings, Keith L; Anderson, Deverick J; Kaye, Keith S

2010-04-01

Hand hygiene noncompliance is a major cause of nosocomial infection. Nosocomial infection cost data exist, but the effect of hand hygiene noncompliance is unknown. To estimate methicillin-resistant Staphylococcus aureus (MRSA)-related cost of an incident of hand hygiene noncompliance by a healthcare worker during patient care. Two models were created to simulate sequential patient contacts by a hand hygiene-noncompliant healthcare worker. Model 1 involved encounters with patients of unknown MRSA status. Model 2 involved an encounter with an MRSA-colonized patient followed by an encounter with a patient of unknown MRSA status. The probability of new MRSA infection for the second patient was calculated using published data. A simulation of 1 million noncompliant events was performed. Total costs of resulting infections were aggregated and amortized over all events. Duke University Medical Center, a 750-bed tertiary medical center in Durham, North Carolina. Model 1 was associated with 42 MRSA infections (infection rate, 0.0042%). Mean infection cost was $47,092 (95% confidence interval [CI], $26,040-$68,146); mean cost per noncompliant event was $1.98 (95% CI, $0.91-$3.04). Model 2 was associated with 980 MRSA infections (0.098%). Mean infection cost was $53,598 (95% CI, $50,098-$57,097); mean cost per noncompliant event was $52.53 (95% CI, $47.73-$57.32). A 200-bed hospital incurs $1,779,283 in annual MRSA infection-related expenses attributable to hand hygiene noncompliance. A 1.0% increase in hand hygiene compliance resulted in annual savings of $39,650 to a 200-bed hospital. Hand hygiene noncompliance is associated with significant attributable hospital costs. Minimal improvements in compliance lead to substantial savings.

Improved accuracy of screw implantation could decrease the incidence of post-operative hydrothorax? O-arm navigation vs. free-hand in thoracic spinal deformity correction surgery.

PubMed

Zhao, Zhihui; Liu, Zhen; Hu, Zongshan; Tseng, Changchun; Li, Jie; Pan, Wei; Qiu, Yong; Zhu, Zezhang

2018-03-16

The purpose of this study was to analyze the occurrence of PE after intra-operative O-arm navigation-assisted surgery and determine whether the post-operative PE incidence could be decreased by using O-arm navigation as compared to conventional free-hand technique. A cohort of 27 patients with spinal deformity who were operated upon with an O-arm navigated system (group A) between 2013 and 2016 were enrolled in the study. A total of 27 curve-matched patients treated by conventional free-hand technique were included as the control group (group B). Whole spine posterior-anterior and lateral radiographs, and CT scans were taken pre and post-operation. Radiologic parameters and volume of PE were measured and compared between the two groups. There were no significant differences in age, Cobb angle, and sagittal contour between the two groups pre-operatively. The mean total volume of post-operative PE was significantly larger in the free-hand group (p < 0.001). In the O-arm group, 59 malpositioned screws were identified in 22 patients. In the free-hand group, 88 malpositioned screws were found among 26 patients. The screw perforation rate was higher in the free-hand group than in the O-arm group (p = 0.007). In the O-arm group, the mean volume of PE was significantly larger among patients with malpositioned screws than those without malpositioned screws (p < 0.001), as well as in the free-hand group. The volume of PE after correction surgery can be significantly decreased by application of O-arm navigation system as compared to conventional free-hand technique. We ascribed the improvement to the accuracy of screw implantation navigated by O-arm.

Variable Operative Experience in Hand Surgery for Plastic Surgery Residents.

PubMed

Silvestre, Jason; Lin, Ines C; Levin, Lawrence Scott; Chang, Benjamin

Efforts to standardize hand surgery training during plastic surgery residency remain challenging. We analyze the variability of operative hand experience at U.S. plastic surgery residency programs. Operative case logs of chief residents in accredited U.S. plastic surgery residency programs were analyzed (2011-2015). Trends in fold differences of hand surgery case volume between the 10th and 90th percentiles of residents were assessed graphically. Percentile data were used to calculate the number of residents achieving case minimums in hand surgery for 2015. Case logs from 818 plastic surgery residents were analyzed of which a minority were from integrated (35.7%) versus independent/combined (64.3%) residents. Trend analysis of fold differences in case volume demonstrated decreasing variability among procedure categories over time. By 2015, fold differences for hand reconstruction, tendon cases, nerve cases, arthroplasty/arthrodesis, amputation, arterial repair, Dupuytren release, and neoplasm cases were below 10-fold. Congenital deformity cases among independent/combined residents was the sole category that exceeded 10-fold by 2015. Percentile data suggested that approximately 10% of independent/combined residents did not meet case minimums for arterial repair and congenital deformity in 2015. Variable operative experience during plastic surgery residency may limit adequate exposure to hand surgery for certain residents. Future studies should establish empiric case minimums for plastic surgery residents to ensure hand surgery competency upon graduation. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Implementation and clinical application of a deformation method for fast simulation of biological tissue formed by fibers and fluid.

PubMed

Sardinha, Ana Gabriella de Oliveira; Oyama, Ceres Nunes de Resende; de Mendonça Maroja, Armando; Costa, Ivan F

2016-01-01

The aim of this paper is to provide a general discussion, algorithm, and actual working programs of the deformation method for fast simulation of biological tissue formed by fibers and fluid. In order to demonstrate the benefit of the clinical applications software, we successfully used our computational program to deform a 3D breast image acquired from patients, using a 3D scanner, in a real hospital environment. The method implements a quasi-static solution for elastic global deformations of objects. Each pair of vertices of the surface is connected and defines an elastic fiber. The set of all the elastic fibers defines a mesh of smaller size than the volumetric meshes, allowing for simulation of complex objects with less computational effort. The behavior similar to the stress tensor is obtained by the volume conservation equation that mixes the 3D coordinates. Step by step, we show the computational implementation of this approach. As an example, a 2D rectangle formed by only 4 vertices is solved and, for this simple geometry, all intermediate results are shown. On the other hand, actual implementations of these ideas in the form of working computer routines are provided for general 3D objects, including a clinical application.

Evaluation of various deformable image registrations for point and volume variations

NASA Astrophysics Data System (ADS)

Han, Su Chul; Lee, Soon Sung; Kim, Mi-Sook; Ji, Young Hoon; Kim, Kum Bae; Choi, Sang Hyun; Park, Seungwoo; Jung, Haijo; Yoo, Hyung Jun; Yi, Chul Young

2015-07-01

The accuracy of deformable image registration (DIR) has a significant dosimetric impact in radiationtreatment planning. Many groups have studied the accuracy of DIR. In this study, we evaluatedthe accuracy of various DIR algorithms by using variations of the deformation point and volume.The reference image (I ref ) and volume (V ref ) were first generated by using virtual deformation QAsoftware (ImSimQA, Oncology System Limited, UK). We deformed I ref with axial movement of thedeformation point and V ref , depending on the type of deformation (relaxation and contraction) inImSimQA software. The deformed image (I def ) and volume (V def ) acquired by using the ImSimQAsoftware were inversely deformed relative to I ref and V ref by using DIR algorithms. As a result,we acquired a deformed image (I id ) from I def and volume (V id ) from V ref . Four intensity-basedalgorithms were tested by following the horn-schunk optical flow (HS), iterative optical flow (IOF),modified demons (MD) and fast demons (FD) with the Deformable Image Registration and AdaptiveRadiotherapy Toolkit (DIRART) of MATLAB. The image similarity between I ref and I id wascalculated to evaluate the accuracy of DIR algorithms using by Normalized Mutual Information(NMI) and Normalized Cross Correlation (NCC) metrics, when the distance of point deformationwas moved 4 mm, the value of NMI was above 1.81 and that of NCC was above 0.99 in all DIRalgorithms. As the degree of deformation was increased, the degree of image similarity decreased.When the V ref was increased or decreased by about 12%, the difference between V ref and V id waswithin ±5% regardless of the type of deformation, the deformation was classified into two types:deformation 1 increased the V ref (relaxation) and deformation 2 decreased the V ref (contraction).The value of the Dice Similarity Coefficient (DSC) was above 0.95 in deformation 1 except for theMD algorithm. In the case of deformation 2, the value of the DSC was above 0.95 in

Teaching Effective Hand Raising to Children with Autism during Group Instruction

ERIC Educational Resources Information Center

Charania, Shaireen M.; LeBlanc, Linda A.; Sabanathan, Narmatha; Ktaech, Inas A.; Carr, James E.; Gunby, Kristin

2010-01-01

We taught 3 children with autism to raise a hand or keep both hands down depending on their status (e.g., having heard a target word, possessing a specific item) using modeling, prompting, and reinforcement. All 3 children acquired accurate hand-raising skills in response to progressively more difficult discrimination tasks during group…

Correction of severe postburn claw hand.

PubMed

Davami, Babak; Pourkhameneh, Golnar

2011-12-01

Burn scar contractures are perhaps the most frequent and most frustrating sequelae of thermal injuries to the hand. Unfortunately, stiffness occurs in the burned hand quickly. A week of neglect in the burned hand can lead to digital malpositioning and distortion that may be difficult to correct. The dorsal contracture is the most common of all the complications of the burned hand. It is the result of damage to the thin dorsal skin and scant subcutaneous tissue, which offers little protection to the deeper structures. Consequently, these injuries are deep resulting in a spectrum of deformities that has remained the bane of reconstructive surgery. Flap coverage will be required in the event of exposure of joints and tendons with absent paratenons. Multiple different flap types are available to treat complex severe postburn hand contractures. In our center, which is the largest regional burn center in northwest Iran, we have considerable experience in the treatment of thermal hand injuries. Between 2005 and 2010, we treated 53 consecutive patients with 65 severe postburn hand deformities. There were 35 men and 18 women with a mean age of 35±3 years. Flame injury was the inciting traumatic event in each patient. The severity of original injury and inadequate early treatment resulted in all of the fingers developing a severe extension contracture with scarred and adherent extensor tendons and subluxed metacarpophalangeal joints. In 36 cases, the injury was in the patients' dominant hand. We first incised the dorsal aspect of the contracted hands where there was maximum tension, then tenolysed the extensor tendons and released the volar capsules, collateral ligaments, and volar plate in all cases. In 30 cases, we also tenolysed the flexor tendons. We reduced the subluxed metacarpophalangeal joints and fixed them with Kirschner wires in 70 to 90 degrees flexion. Then, we planned and performed axial groin flaps to reconstruct the defects in all of them. In all of these

T\\overline{T} -deformations, AdS/CFT and correlation functions

NASA Astrophysics Data System (ADS)

Giribet, Gaston

2018-02-01

A solvable irrelevant deformation of AdS3/CFT2 correspondence leading to a theory with Hagedorn spectrum at high energy has been recently proposed. It consists of a single trace deformation of the boundary theory, which is inspired by the recent work on solvable T\\overline{T} deformations of two-dimensional CFTs. Thought of as a worldsheet σ-model, the interpretation of the deformed theory from the bulk viewpoint is that of string theory on a background that interpolates between AdS3 in the IR and a linear dilaton vacuum of little string theory in the UV. The insertion of the operator that realizes the deformation in the correlation functions produces a logarithmic divergence, leading to the renormalization of the primary operators, which thus acquire an anomalous dimension. We compute this anomalous dimension explicitly, and this provides us with a direct way of determining the spectrum of the theory. We discuss this and other features of the correlation functions in presence of the deformation.

Congenital hand anomalies in Upper Egypt

PubMed Central

Abulezz, Tarek; Talaat, Mohamed; Elsani, Asem; Allam, Karam

2016-01-01

Background: Congenital hand anomalies are numerous and markedly variant. Their significance is attributed to the frequent occurrence and their serious social, psychological and functional impacts on patient's life. Patients and Methods: This is a follow-up study of 64 patients with hand anomalies of variable severity. All patients were presented to Plastic Surgery Department of Sohag University Hospital in a period of 24 months. Results: This study revealed that failure of differentiation and duplication deformities were the most frequent, with polydactyly was the most common anomaly encountered. The mean age of presentation was 6 years and female to male ratio was 1.46:1. Hand anomalies were either isolated, associated with other anomalies or part of a syndrome. Conclusion: Incidence of congenital hand anomalies in Upper Egypt is difficult to be estimated due to social and cultural concepts, lack of education, poor registration and deficient medical survey. Management of hand anomalies should be individualised, carefully planned and started as early as possible to achieve the best outcome. PMID:27833283

[Which foot deformities should be radiologist be familiar with?

PubMed

von Stillfried, E

2018-05-01

Most deformities of the foot are visible at birth and can be diagnosed without imaging. They can be divided into congenital flexible, congenital structural and acquired foot deformities. The most common congenital flexible foot deformity in children is the metatarsus adductus, which usually requires no long-term therapy. Regarding congenital structural deformities, such as the clubfoot and talus verticalis, plaster therapy should be started during the first week of life, so that by the end of the first year of life and the beginning of the verticalization, a pain-free resilient foot with normal function is present. Imaging is usually only necessary if a relapse arises. Coalitio of the tarsal bones is often visible only in the course of growth through the development of a rigid flatfoot and always requires imaging to confirm the diagnosis. This article is intended to give the radiologist an overview of the most important deformities and to inform about their course and therapy.

High-Efficiency Multiscale Modeling of Cell Deformations in Confined Microenvironments in Microcirculation and Microfluidics

NASA Astrophysics Data System (ADS)

Lu, Huijie; Peng, Zhangli

2017-11-01

We developed a high-efficiency multiscale modeling method to predict the stress and deformation of cells during the interactions with their microenvironments in microcirculation and microfluidics, including red blood cells (RBCs) and circulating tumor cells (CTCs). There are more than 1 billion people in the world suffering from RBC diseases. The mechanical properties of RBCs are changed in these diseases due to molecular structure alternations, which is not only important for understanding the disease pathology but also provides an opportunity for diagnostics. On the other hand, the mechanical properties of cancer cells are also altered compared to healthy cells. This can lead to acquired ability to cross the narrow capillary networks and endothelial gaps, which is crucial for metastasis, the leading cause of cancer mortality. Therefore, it is important to predict the deformation and stress of RBCs and CTCs in microcirculations. We develop a high-efficiency multiscale model of cell-fluid interaction. We pass the information from our molecular scale models to the cell scale to study the effect of molecular mutations. Using our high-efficiency boundary element methods of fluids, we will be able to run 3D simulations using a single CPU within several hours, which will enable us to run extensive parametric studies and optimization.

[Acquired disorders of color vision].

PubMed

Lascu, Lidia; Balaş, Mihaela

2002-01-01

This article is a general view of acquired disorders of color vision. The revision of the best known methods and of the etiopathogenic classification is not very important in ophthalmology but on the other hand, the detection of the blue defect advertise and associated ocular pathology. There is a major interest in serious diseases as multiple sclerosis, AIDS, diabetes melitus, when the first ocular sign can be a defect in the color vision.

Personal authentication using hand vein triangulation and knuckle shape.

PubMed

Kumar, Ajay; Prathyusha, K Venkata

2009-09-01

This paper presents a new approach to authenticate individuals using triangulation of hand vein images and simultaneous extraction of knuckle shape information. The proposed method is fully automated and employs palm dorsal hand vein images acquired from the low-cost, near infrared, contactless imaging. The knuckle tips are used as key points for the image normalization and extraction of region of interest. The matching scores are generated in two parallel stages: (i) hierarchical matching score from the four topologies of triangulation in the binarized vein structures and (ii) from the geometrical features consisting of knuckle point perimeter distances in the acquired images. The weighted score level combination from these two matching scores are used to authenticate the individuals. The achieved experimental results from the proposed system using contactless palm dorsal-hand vein images are promising (equal error rate of 1.14%) and suggest more user friendly alternative for user identification.

Sports Injury-Related Fingers and Thumb Deformity Due to Tendon or Ligament Rupture.

PubMed

Bai, Rong-Jie; Zhang, Hui-Bo; Zhan, Hui-Li; Qian, Zhan-Hua; Wang, Nai-Li; Liu, Yue; Li, Wen-Ting; Yin, Yu-Ming

2018-05-05

Hand injuries are very common in sports, such as skiing and ball sports. One of the major reasons causing hand and finger deformity is due to ligament and tendon injury. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) can demonstrate the complex anatomy of the fingers and thumb, especially the tendons and ligaments, and provide the accurate diagnosis of clinically important fingers and thumbs deformity due to ligamentous and tendinous injuries during sport activities. Sixteen fresh un-embalmed cadaveric hands were harvested from eight cadavers. A total of 20 healthy volunteers' hands and 44 patients with fingers or thumb deformity due to sports-related injuries were included in this study. All subjects had MR examination with T1-weighted images and proton density-weighted imaging with fat suppression (PD FS) in axial, coronal, and sagittal plane, respectively. Subsequently, all 16 cadaveric hands were sliced into 2-mm thick slab with a band saw (six in coronal plane, six in sagittal plane, and four in axial plane). The correlation of anatomic sections and the MRI characteristics of tendons of fingers and the ulnar collateral ligament (UCL) at the metacarpal phalangeal joint (MCPJ) of thumb between 20 healthy volunteers and 44 patients (confirmed by surgery) were analyzed. The normal ligaments and tendons in 16 cadaveric hands and 20 volunteers' hands showed uniform low-signal intensity on all the sequences of the MRI. Among 44 patients with tendinous and ligamentous injuries in the fingers or thumb, 12 cases with UCL injury at MCPJ of the thumb (Stener lesion = 8 and non-Stener lesion = 4), 6 cases with the central slip injury, 12 cases with terminal tendon injury, and 14 cases with flexor digitorum profundus injury. The ligaments and tendons disruption manifested as increased signal intensity and poor definition, discontinuity, and heterogeneous signal intensity of the involved ligaments and tendons. Sports

Exposure of the surgeon's hands to radiation during hand surgery procedures.

PubMed

Żyluk, Andrzej; Puchalski, Piotr; Szlosser, Zbigniew; Dec, Paweł; Chrąchol, Joanna

2014-01-01

The objective of the study was to assess the time of exposure of the surgeon's hands to radiation and calculate of the equivalent dose absorbed during surgery of hand and wrist fractures with C-arm fluoroscope guidance. The necessary data specified by the objective of the study were acquired from operations of 287 patients with fractures of fingers, metacarpals, wrist bones and distal radius. 218 operations (78%) were percutaneous procedures and 60 (22%) were performed by open method. Data on the time of exposure and dose of radiation were acquired from the display of the fluoroscope, where they were automatically generated. These data were assigned to the individual patient, type of fracture, method of surgery and the operating surgeon. Fixations of distal radial fractures required longer times of radiation exposure (mean 61 sec.) than fractures of the wrist/metacarpals and fingers (38 and 32 sec., respectively), which was associated with absorption of significantly higher equivalent doses. Fixations of distal radial fractures by open method were associated with statistically significantly higher equivalent doses (0.41 mSv) than percutaneous procedures (0.3 mSv). Fixations of wrist and metacarpal bone fractures by open method were associated with lower equivalent doses (0.34 mSv) than percutaneous procedures (0.37 mSv),but the difference was not significant. Fixations of finger fractures by open method were associated with lower equivalent doses (0.13 mSv) than percutaneous procedures (0.24 mSv), the difference being statistically non-significant. Statistically significant differences in exposure time and equivalent doses were noted between 4 surgeons participating in the study, but no definitive relationship was found between these parameters and surgeons' employment time. 1. Hand surgery procedures under fluoroscopic guidance are associated with mild exposure of the surgeons' hands to radiation. 2. The equivalent dose was related to the type of fracture

SU-E-J-111: Finite Element-Based Deformable Image Registration of Pleural Cavity for Photodynamic Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Penjweini, R; Zhu, T

Purpose: The pleural volumes will deform during surgery portion of the pleural photodynamic therapy (PDT) of lung cancer when the pleural cavity is opened. This impact the delivered dose when using highly conformal treatment techniques. In this study, a finite element-based (FEM) deformable image registration is used to quantify the anatomical variation between the contours for the pleural cavities obtained in the operating room and those determined from pre-surgery computed tomography (CT) scans. Methods: An infrared camera-based navigation system (NDI) is used during PDT to track the anatomical changes and contour the lung and chest cavity. A series of CTsmore » of the lungs, in the same patient, are also acquired before the surgery. The structure contour of lung and the CTs are processed and contoured in Matlab and MeshLab. Then, the contours are imported into COMSOL Multiphysics 5.0, where the FEM-based deformable image registration is obtained using the deformed mesh - moving mesh (ALE) model. The NDI acquired lung contour is considered as the reference contour, and the CT contour is used as the target one, which will be deformed. Results: The reconstructed three-dimensional contours from both NDI and CT can be converted to COMSOL so that a three-dimensional ALE model can be developed. The contours can be registered using COMSOL ALE moving mesh model, which takes into account the deformation along x, y and z-axes. The deformed contour has good matches to the reference contour after the dynamic matching process. The resulting 3D deformation map can be used to obtain the locations of other critical anatomic structures, e.g., heart, during surgery. Conclusion: Deformable image registration can fuse images acquired by different modalities. It provides insights into the development of phenomenon and variation in normal anatomical structures over time. The initial assessments of three-dimensional registration show good agreement.« less

The effect of hand hygiene compliance on hospital-acquired infections in an ICU setting in a Kuwaiti teaching hospital.

PubMed

Salama, Mona F; Jamal, Wafaa Y; Mousa, Haifa Al; Al-Abdulghani, Khaled A; Rotimi, Vincent O

2013-02-01

Hand washing is widely accepted as the cornerstone of infection control in the intensive care unit (ICU). Nosocomial infections are frequently viewed as indicating poor compliance with hand washing guidelines. To determine the hand hygiene (HH) compliance rate among healthcare workers (HCWs) and its effect on the nosocomial infection rates in the ICU of our hospital, we conducted an interventional study. The study spanned a period of 7 months (February 2011-August 2011) and consisted of education about HH indications and techniques, workplace reminder posters, focused group sessions, and feedback on the HH compliance and infection rates. The WHO HH observation protocol was used both before and after a hospital-wide HH campaign directed at all staff members, particularly those in the ICU. Compliance was measured by direct observation of the HCWs, using observation record forms in a patient-directed manner, with no more than two patients observed simultaneously. The overall HH compliance rate was calculated by dividing the number of HH actions by the total number of HH opportunities. The nosocomial infection rates for the pre- and post-interventional periods were also compared to establish the effect of the intervention on rate of infections acquired within the unit. The overall rate of HH compliance by all the HCWs increased from 42.9% pre-intervention to 61.4% post-intervention, P<0.001. Individually, the compliance was highest among the nurses, 49.9 vs. 82.5%, respectively (P<0.001) and lowest among the doctors, 38.6 vs. 43.2%, respectively (P=0.24). The effect of the increase in the HH compliance rate on the nosocomial infection rate was remarkable. There were significant reductions in the following: the rate of overall health care-associated infections/1000 patient-days, which fell from 37.2 pre-intervention to 15.1 post-intervention (P<0.001); the rate of bloodstream infections, which fell from 18.6 to 3.4/1000 central-line-days (P<0.001); and the rate of lower

Cognitive Achievement and Motivation in Hands-on and Teacher-Centred Science Classes: Does an additional hands-on consolidation phase (concept mapping) optimise cognitive learning at work stations?

NASA Astrophysics Data System (ADS)

Gerstner, Sabine; Bogner, Franz X.

2010-05-01

Our study monitored the cognitive and motivational effects within different educational instruction schemes: On the one hand, teacher-centred versus hands-on instruction; on the other hand, hands-on instruction with and without a knowledge consolidation phase (concept mapping). All the instructions dealt with the same content. For all participants, the hands-on approach as well as the concept mapping adaptation were totally new. Our hands-on approach followed instruction based on "learning at work stations". A total of 397 high-achieving fifth graders participated in our study. We used a pre-test, post-test, retention test design both to detect students' short-term learning success and long-term learning success, and to document their decrease rates of newly acquired knowledge. Additionally, we monitored intrinsic motivation. Although the teacher-centred approach provided higher short-term learning success, hands-on instruction resulted in relatively lower decrease rates. However, after six weeks, all students reached similar levels of newly acquired knowledge. Nevertheless, concept mapping as a knowledge consolidation phase positively affected short-term increase in knowledge. Regularly placed in instruction, it might increase long-term retention rates. Scores of interest, perceived competence and perceived choice were very high in all the instructional schemes.

Stent Design Affects Femoropopliteal Artery Deformation.

PubMed

MacTaggart, Jason; Poulson, William; Seas, Andreas; Deegan, Paul; Lomneth, Carol; Desyatova, Anastasia; Maleckis, Kaspars; Kamenskiy, Alexey

2018-03-23

Poor durability of femoropopliteal artery (FPA) stenting is multifactorial, and severe FPA deformations occurring with limb flexion are likely involved. Different stent designs result in dissimilar stent-artery interactions, but the degree of these effects in the FPA is insufficiently understood. To determine how different stent designs affect limb flexion-induced FPA deformations. Retrievable markers were deployed into n = 28 FPAs of lightly embalmed human cadavers. Bodies were perfused and CT images were acquired with limbs in the standing, walking, sitting, and gardening postures. Image analysis allowed measurement of baseline FPA foreshortening, bending, and twisting associated with each posture. Markers were retrieved and 7 different stents were deployed across the adductor hiatus in the same limbs. Markers were then redeployed in the stented FPAs, and limbs were reimaged. Baseline and stented FPA deformations were compared to determine the influence of each stent design. Proximal to the stent, Innova, Supera, and SmartFlex exacerbated foreshortening, SmartFlex exacerbated twisting, and SmartControl restricted bending of the FPA. Within the stent, all devices except Viabahn restricted foreshortening; Supera, SmartControl, and AbsolutePro restricted twisting; SmartFlex and Innova exacerbated twisting; and Supera and Viabahn restricted bending. Distal to the stents, all devices except AbsolutePro and Innova exacerbated foreshortening, and Viabahn, Supera, Zilver, and SmartControl exacerbated twisting. All stents except Supera were pinched in flexed limb postures. Peripheral self-expanding stents significantly affect limb flexion-induced FPA deformations, but in different ways. Although certain designs seem to accommodate some deformation modes, no device was able to match all FPA deformations.

A quantitative comparison of the performance of three deformable registration algorithms in radiotherapy

PubMed Central

Fabri, Daniella; Zambrano, Valentina; Bhatia, Amon; Furtado, Hugo; Bergmann, Helmar; Stock, Markus; Bloch, Christoph; Lütgendorf-Caucig, Carola; Pawiro, Supriyanto; Georg, Dietmar; Birkfellner, Wolfgang; Figl, Michael

2013-01-01

We present an evaluation of various non-rigid registration algorithms for the purpose of compensating interfractional motion of the target volume and organs at risk areas when acquiring CBCT image data prior to irradiation. Three different deformable registration (DR) methods were used: the Demons algorithm implemented in the iPlan Software (BrainLAB AG, Feldkirchen, Germany) and two custom-developed piecewise methods using either a Normalized Correlation or a Mutual Information metric (featureletNC and featureletMI). These methods were tested on data acquired using a novel purpose-built phantom for deformable registration and clinical CT/CBCT data of prostate and lung cancer patients. The Dice similarity coefficient (DSC) between manually drawn contours and the contours generated by a derived deformation field of the structures in question was compared to the result obtained with rigid registration (RR). For the phantom, the piecewise methods were slightly superior, the featureletNC for the intramodality and the featureletMI for the intermodality registrations. For the prostate cases in less than 50% of the images studied the DSC was improved over RR. Deformable registration methods improved the outcome over a rigid registration for lung cases and in the phantom study, but not in a significant way for the prostate study. A significantly superior deformation method could not be identified. PMID:23969092

Complex surface deformation of Akutan volcano, Alaska revealed from InSAR time series

NASA Astrophysics Data System (ADS)

Wang, Teng; DeGrandpre, Kimberly; Lu, Zhong; Freymueller, Jeffrey T.

2018-02-01

Akutan volcano is one of the most active volcanoes in the Aleutian arc. An intense swarm of volcano-tectonic earthquakes occurred across the island in 1996. Surface deformation after the 1996 earthquake sequence has been studied using Interferometric Synthetic Aperture Radar (InSAR), yet it is hard to determine the detailed temporal behavior and spatial extent of the deformation due to decorrelation and the sparse temporal sampling of SAR data. Atmospheric delay anomalies over Akutan volcano are also strong, bringing additional technical challenges. Here we present a time series InSAR analysis from 2003 to 2016 to reveal the surface deformation in more detail. Four tracks of Envisat data acquired from 2003 to 2010 and one track of TerraSAR-X data acquired from 2010 to 2016 are processed to produce high-resolution surface deformation, with a focus on studying two transient episodes of inflation in 2008 and 2014. For the TerraSAR-X data, the atmospheric delay is estimated and removed using the common-master stacking method. These derived deformation maps show a consistently uplifting area on the northeastern flank of the volcano. From the TerraSAR-X data, we quantify the velocity of the subsidence inside the caldera to be as high as 10 mm/year, and identify another subsidence area near the ground cracks created during the 1996 swarm.

Illumination-invariant and deformation-tolerant inner knuckle print recognition using portable devices.

PubMed

Xu, Xuemiao; Jin, Qiang; Zhou, Le; Qin, Jing; Wong, Tien-Tsin; Han, Guoqiang

2015-02-12

We propose a novel biometric recognition method that identifies the inner knuckle print (IKP). It is robust enough to confront uncontrolled lighting conditions, pose variations and low imaging quality. Such robustness is crucial for its application on portable devices equipped with consumer-level cameras. We achieve this robustness by two means. First, we propose a novel feature extraction scheme that highlights the salient structure and suppresses incorrect and/or unwanted features. The extracted IKP features retain simple geometry and morphology and reduce the interference of illumination. Second, to counteract the deformation induced by different hand orientations, we propose a novel structure-context descriptor based on local statistics. To our best knowledge, we are the first to simultaneously consider the illumination invariance and deformation tolerance for appearance-based low-resolution hand biometrics. Settings in previous works are more restrictive. They made strong assumptions either about the illumination condition or the restrictive hand orientation. Extensive experiments demonstrate that our method outperforms the state-of-the-art methods in terms of recognition accuracy, especially under uncontrolled lighting conditions and the flexible hand orientation requirement.

Illumination-Invariant and Deformation-Tolerant Inner Knuckle Print Recognition Using Portable Devices

PubMed Central

Xu, Xuemiao; Jin, Qiang; Zhou, Le; Qin, Jing; Wong, Tien-Tsin; Han, Guoqiang

2015-01-01

We propose a novel biometric recognition method that identifies the inner knuckle print (IKP). It is robust enough to confront uncontrolled lighting conditions, pose variations and low imaging quality. Such robustness is crucial for its application on portable devices equipped with consumer-level cameras. We achieve this robustness by two means. First, we propose a novel feature extraction scheme that highlights the salient structure and suppresses incorrect and/or unwanted features. The extracted IKP features retain simple geometry and morphology and reduce the interference of illumination. Second, to counteract the deformation induced by different hand orientations, we propose a novel structure-context descriptor based on local statistics. To our best knowledge, we are the first to simultaneously consider the illumination invariance and deformation tolerance for appearance-based low-resolution hand biometrics. Settings in previous works are more restrictive. They made strong assumptions either about the illumination condition or the restrictive hand orientation. Extensive experiments demonstrate that our method outperforms the state-of-the-art methods in terms of recognition accuracy, especially under uncontrolled lighting conditions and the flexible hand orientation requirement. PMID:25686317

All Madelung deformities are not endocrine

PubMed Central

Kumar, Ajay; Rai, Gopal K.; Akhtar, Javed; Phillip, Rajeev; Gutch, Manish; Arya, T. V. S.

2013-01-01

Madelung deformity is a rare inherited disorder associated with endocrine disorders like Turner's syndrome, pseudohypoparathyroidism, but can be seen with short stature homeobox deficiency conditions such as Leri-Weill dyschondrosteosis (LWD) and Langers mesomelic dysplasia. It has also been reported following trauma to the distal radius epiphysis neoplasia mucopolysaccharidosis (MPS) and achondroplasia. Madelung deformity is an abnormality of distal radial epiphysis where in progressive ulnar and volar tilt of the articular surface occurring in association with distal subluxation of ulna. A 13-year-old girl was referred to us for evaluation of bilateral deformity of wrist and short stature. There was ulnar deviation and dorsal tilt of bilateral hands without history of pain to the joint trauma and family history of similar illness. On X-ray, wrist showed malformed distal radial epiphysis with dorsal and ulnar shift and with increased length of phalanges suggestive of Madelung deformity. X-ray spine was normal. Ultrasound abdomen showed normal uterus and ovary and her follicle stimulating hormone. Luteinizing hormone was normal and so was urine MPS screening. Based on the above points the diagnosis of LWD was made. PMID:24251169

All Madelung deformities are not endocrine.

PubMed

Kumar, Ajay; Rai, Gopal K; Akhtar, Javed; Phillip, Rajeev; Gutch, Manish; Arya, T V S

2013-10-01

Madelung deformity is a rare inherited disorder associated with endocrine disorders like Turner's syndrome, pseudohypoparathyroidism, but can be seen with short stature homeobox deficiency conditions such as Leri-Weill dyschondrosteosis (LWD) and Langers mesomelic dysplasia. It has also been reported following trauma to the distal radius epiphysis neoplasia mucopolysaccharidosis (MPS) and achondroplasia. Madelung deformity is an abnormality of distal radial epiphysis where in progressive ulnar and volar tilt of the articular surface occurring in association with distal subluxation of ulna. A 13-year-old girl was referred to us for evaluation of bilateral deformity of wrist and short stature. There was ulnar deviation and dorsal tilt of bilateral hands without history of pain to the joint trauma and family history of similar illness. On X-ray, wrist showed malformed distal radial epiphysis with dorsal and ulnar shift and with increased length of phalanges suggestive of Madelung deformity. X-ray spine was normal. Ultrasound abdomen showed normal uterus and ovary and her follicle stimulating hormone. Luteinizing hormone was normal and so was urine MPS screening. Based on the above points the diagnosis of LWD was made.

Hand held phase-shifting diffraction Moire interferometer

DOEpatents

Deason, V.A.; Ward, M.B.

1994-09-20

An interferometer is described in which a coherent beam of light is generated within a remote case and transmitted to a hand held unit tethered to said remote case, said hand held unit having optical elements for directing a pair of mutually coherent collimated laser beams at a diffraction grating. Data from the secondary or diffracted beams are then transmitted to a separate video and data acquisition system for recording and analysis for load induced deformation or for identification purposes. Means are also provided for shifting the phase of one incident beam relative to the other incident beam and being controlled from within said remote case. 4 figs.

Hand held phase-shifting diffraction moire interferometer

DOEpatents

Deason, Vance A.; Ward, Michael B.

1994-01-01

An interferometer in which a coherent beam of light is generated within a remote case and transmitted to a hand held unit tethered to said remote case, said hand held unit having optical elements for directing a pair of mutually coherent collimated laser beams at a diffraction grating. Data from the secondary or diffracted beams are then transmitted to a separate video and data acquisition system for recording and analysis for load induced deformation or for identification purposes. Means are also provided for shifting the phase of one incident beam relative to the other incident beam and being controlled from within said remote case.

Deformable medical image registration of pleural cavity for photodynamic therapy by using finite-element based method

NASA Astrophysics Data System (ADS)

Penjweini, Rozhin; Kim, Michele M.; Dimofte, Andrea; Finlay, Jarod C.; Zhu, Timothy C.

2016-03-01

When the pleural cavity is opened during the surgery portion of pleural photodynamic therapy (PDT) of malignant mesothelioma, the pleural volume will deform. This impacts the delivered dose when using highly conformal treatment techniques. To track the anatomical changes and contour the lung and chest cavity, an infrared camera-based navigation system (NDI) is used during PDT. In the same patient, a series of computed tomography (CT) scans of the lungs are also acquired before the surgery. The reconstructed three-dimensional contours from both NDI and CTs are imported into COMSOL Multiphysics software, where a finite element-based (FEM) deformable image registration is obtained. The CT contour is registered to the corresponding NDI contour by overlapping the center of masses and aligning their orientations. The NDI contour is considered as the reference contour, and the CT contour is used as the target one, which will be deformed. Deformed Geometry model is applied in COMSOL to obtain a deformed target contour. The distortion of the volume at X, Y and Z is mapped to illustrate the transformation of the target contour. The initial assessment shows that FEM-based image deformable registration can fuse images acquired by different modalities. It provides insights into the deformation of anatomical structures along X, Y and Z-axes. The deformed contour has good matches to the reference contour after the dynamic matching process. The resulting three-dimensional deformation map can be used to obtain the locations of other critical anatomic structures, e.g., heart, during surgery.

Acquired midfoot deformity and function in individuals with diabetes and peripheral neuropathy.

PubMed

Hastings, Mary K; Mueller, Michael J; Woodburn, James; Strube, Michael J; Commean, Paul; Johnson, Jeffrey E; Cheuy, Victor; Sinacore, David R

2016-02-01

Diabetes mellitus related medial column foot deformity is a major contributor to ulceration and amputation. However, little is known about the relationship between medial column alignment and function and the integrity of the soft tissues that support and move the medial column. The purposes of this study were to determine the predictors of medial column alignment and function in people with diabetes and peripheral neuropathy. 23 participants with diabetes and neuropathy had radiographs, heel rise kinematics, magnetic resonance imaging and isokinetic muscle testing to measure: 1) medial column alignment (Meary's angle--the angle between the 1st metatarsal longitudinal axis and the talar head and neck), 2) medial column function (forefoot relative to hindfoot plantarflexion during heel rise), 3) intrinsic foot muscle and fat volume, ratio of posterior tibialis to flexor digitorum tendon volume, 4) plantar fascia function (Meary's angle change from toes flat to extended) and 5) plantarflexor peak torque. Predictors of medial column alignment and function were determined using simultaneous entry multiple regression. Posterior tibialis to flexor digitorum tendon volume ratio and intrinsic foot muscle volume were significant predictors of medial column alignment (P<.05), accounting for 44% of the variance. Intrinsic foot fat volume and plantarflexor peak torque were significant predictors of medial column function (P<.05), accounting for 37% of the variance. Deterioration of medial column supporting structures predicted alignment and function. Prospective research is required to monitor alignment, structure, and function over time to inform early intervention strategies to prevent deformity, ulceration, and amputation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Extensor Tendon Injuries and Repairs in the Hand

PubMed Central

Kontor, J. A.

1982-01-01

Due to their superficial course, the extensor tendons are frequently lacerated over the dorsum of the hand and fingers. Excellent functional results are obtained in repairs of simple tendon lacerations. ‘Open’ mallet lacerations over the distal IP joint or involving the central extensor slip over the proximal IP joint require more precise suturing methods. More proximal extensor tendon divisions near the wrist involve dissection of the retracted finger extensors or long thumb extensor in the distal forearm and more formal tendon repairs, including a possible tendon transfer to the thumb. ‘Closed injuries’, with varying degrees of extensor tendon disruption, occur at three main sites. The mallet injury at the DIP joint and the boutonnière deformity over the PIP joint are sometimes recognized late, but respond to conservative splinting for a minimum of four weeks with guarded motion avoiding secondary stiffening of the remaining small joints of the hand. Surgery of closed injuries most frequently involves the intra-articular traction fracture type of mallet deformities in which the DIP joint has taken the brunt of the injury. PMID:21286174

Application of the IFSSH(3)-classification for congenital anomalies of the hand; results and problems.

PubMed

De Smet, L; Matton, G; Monstrey, S; Cambier, E; Fabry, G

1997-09-01

The extended classification proposed by the IFSSH was used to classify 1013 hand anomalies in 925 hands of 650 patients. We found associated anomalies in 26.7%. The classification was straightforward in 86%, difficult in 6.6% and not possible in 7.8%. In group I the radial and ulnar deficiencies, limited to the hand and without forearm deficiencies should be included. Group II was the most important group including 513 anomalies. We propose to include in this group the Madelung deformity, the Kirner deformity and congenital trigger fingers and trigger thumbs. Triphalangeal thumbs are a problem, we suggest to list this anomaly in group III and to consider it as a duplication in length. It is not always possible to evaluate the (transverse) absence of the fingers or hand. Longitudinal deficiencies (group IIB), symbrachydactyly group (V) and amniotic bands (group VI) occasionally develop a phenotype similar to the genuine transverse deficiency (group IA).

SU-E-J-218: Novel Validation Paradigm of MRI to CT Deformation of Prostate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Padgett, K; University of Miami School of Medicine - Radiology, Miami, FL; Pirozzi, S

2015-06-15

Purpose: Deformable registration algorithms are inherently difficult to characterize in the multi-modality setting due to a significant differences in the characteristics of the different modalities (CT and MRI) as well as tissue deformations. We present a unique paradigm where this is overcome by utilizing a planning-MRI acquired within an hour of the planning-CT serving as a surrogate for quantifying MRI to CT deformation by eliminating the issues of multi-modality comparisons. Methods: For nine subjects, T2 fast-spin-echo images were acquired at two different time points, the first several weeks prior to planning (diagnostic-MRI) and the second on the same day asmore » the planning-CT (planning-MRI). Significant effort in patient positioning and bowel/bladder preparation was undertaken to minimize distortion of the prostate in all datasets. The diagnostic-MRI was rigidly and deformably aligned to the planning-CT utilizing a commercially available deformable registration algorithm synthesized from local registrations. Additionally, the quality of rigid alignment was ranked by an imaging physicist. The distances between corresponding anatomical landmarks on rigid and deformed registrations (diagnostic-MR to planning-CT) were evaluated. Results: It was discovered that in cases where the rigid registration was of acceptable quality the deformable registration didn’t improve the alignment, this was true of all metrics employed. If the analysis is separated into cases where the rigid alignment was ranked as unacceptable the deformable registration significantly improved the alignment, 4.62mm residual error in landmarks as compared to 5.72mm residual error in rigid alignments with a p-value of 0.0008. Conclusion: This paradigm provides an ideal testing ground for MR to CT deformable registration algorithms by allowing for inter-modality comparisons of multi-modality registrations. Consistent positioning, bowel and bladder preparation may Result in higher quality

Accelerating dewetting on deformable substrates by adding a liquid underlayer.

PubMed

Xu, Lin; Reiter, Günter; Shi, Tongfei; An, Lijia

2010-05-18

We investigated the dependence of the dewetting velocity of a thin, low-viscosity polystyrene (PS) top film on a poly(methyl methacrylate) (PMMA) double layer consisting of a low-viscosity underlayer of thickness h(L) coated with a high-viscosity middle layer of thickness h(M). The addition of the liquid underlayer generated complex nonmonotonic behavior of the dewetting velocity as a function of increasing h(M). In particular, we observed an acceleration of dewetting for an intermediate range of h(M). This phenomenon has been interpreted by a combination deformation of the middle elastic layer and a concurrent change in the contact angle. On one hand, deformation led to the formation of a trench that dissipated energy during its movement through the liquid underlayer and thus caused a slowing down of dewetting. However, with an increase in the thickness of the elastic middle layer, the size of the trench decreased and its influence on the dewetting velocity also decreased. On the other hand, the deformation of the elastic layer also led to an increase in the contact angle. This increase in the driving capillary forces caused an increase in the dewetting velocity.

Deformation interplay at Hawaii Island

NASA Astrophysics Data System (ADS)

Shirzaei, M.; Walter, T. R.

2009-12-01

Volcanoes are known to be closely related to the tectonic environment, including vent locations and eruptions resulting from faults and earthquakes. Similarly, adjacent volcanoes interact with each other in time and space, as suggested for the Hawaiian volcanoes Kilauea and Mauna Loa. New satellite radar data imply even more complex deformation interplay in Hawaii than previously thought, involving magma chamber pressure changes, dike intrusions, slow earthquakes and ground subsidence. The affected regions are the Mauna Loa and Kilauea volcano summits, their active rift zones, the island’s unstable southeast flank and even the capital city of Hilo. Based on the data acquired by the European satellite ENVISAT, we present in this work a five-year spatio-temporal analysis of the deformation signals recorded between 2003 and 2008. The data suggests that most of the deformation sources are acting in chorus. The magma intrusion at the Mauna Loa chamber and the intrusion into the Kilauea rift dike are correlated in time while also interacting with gravity-driven flank movement events. Some of the events occur silently underneath the Kilauea south flank, such as slow earthquakes that may largely affect all of the active magmatic systems and reverse their sign of correlation. This study of the interplay between multiple deformations and inherently coupled systems provides a better understanding of Hawaiian volcano activity and may lead to new methods for assessing the hazards that arise during volcano-tectonic activities elsewhere.

Deformation of two-phase aggregates using standard numerical methods

NASA Astrophysics Data System (ADS)

Duretz, Thibault; Yamato, Philippe; Schmalholz, Stefan M.

2013-04-01

Geodynamic problems often involve the large deformation of material encompassing material boundaries. In geophysical fluids, such boundaries often coincide with a discontinuity in the viscosity (or effective viscosity) field and subsequently in the pressure field. Here, we employ popular implementations of the finite difference and finite element methods for solving viscous flow problems. On one hand, we implemented finite difference method coupled with a Lagrangian marker-in-cell technique to represent the deforming fluid. Thanks to it Eulerian nature, this method has a limited geometric flexibility but is characterized by a light and stable discretization. On the other hand, we employ the Lagrangian finite element method which offers full geometric flexibility at the cost of relatively heavier discretization. In order to test the accuracy of the finite difference scheme, we ran large strain simple shear deformation of aggregates containing either weak of strong circular inclusion (1e6 viscosity ratio). The results, obtained for different grid resolutions, are compared to Lagrangian finite element results which are considered as reference solution. The comparison is then used to establish up to which strain can finite difference simulations be run given the nature of the inclusions (dimensions, viscosity) and the resolution of the Eulerian mesh.

Kaiser Permanente National Hand Hygiene Program

PubMed Central

Barnes, Sue; Barron, Dana; Becker, Linda; Canola, Teresa; Salemi, Charles

2004-01-01

Objective: Hand hygiene has historically been identified as an important intervention for preventing infection acquired in health care settings. Recently, the advent of waterless, alcohol-based skin degermer and elimination of artificial nails have been recognized as other important interventions for preventing infection. Supplied with this information, the National Infection Control Peer Group convened a KP Hand Hygiene Work Group, which, in August 2001, launched a National Hand Hygiene Program initiative titled “Infection Control: It’s In Our Hands” to increase compliance with hand hygiene throughout the Kaiser Permanente (KP) organization. Design: The infection control initiative was designed to include employee and physician education as well as to implement standard hand hygiene products (eg, alcohol degermers), eliminate use of artificial nails, and monitor outcomes. Results: From 2001 through September 2003, the National KP Hand Hygiene Work Group coordinated implementation of the Hand Hygiene initiative throughout the KP organization. To date, outcome monitoring has shown a 26% increase in compliance with hand hygiene as well as a decrease in the number of bloodstream infections and methycillin-resistant Staphylococcus aureus (MRSA) infections. As of May 2003, use of artificial nails had been reduced by 97% nationwide. Conclusions: Endorsement of this Hand Hygiene Program initiative by KP leadership has led to implementation of the initiative at all medical centers throughout the KP organization. Outcome indicators to date suggest that the initiative has been successful; final outcome monitoring will be completed in December 2003. PMID:26704605

Toward the development of intrafraction tumor deformation tracking using a dynamic multi-leaf collimator

PubMed Central

Ge, Yuanyuan; O’Brien, Ricky T.; Shieh, Chun-Chien; Booth, Jeremy T.; Keall, Paul J.

2014-01-01

Purpose: Intrafraction deformation limits targeting accuracy in radiotherapy. Studies show tumor deformation of over 10 mm for both single tumor deformation and system deformation (due to differential motion between primary tumors and involved lymph nodes). Such deformation cannot be adapted to with current radiotherapy methods. The objective of this study was to develop and experimentally investigate the ability of a dynamic multi-leaf collimator (DMLC) tracking system to account for tumor deformation. Methods: To compensate for tumor deformation, the DMLC tracking strategy is to warp the planned beam aperture directly to conform to the new tumor shape based on real time tumor deformation input. Two deformable phantoms that correspond to a single tumor and a tumor system were developed. The planar deformations derived from the phantom images in beam's eye view were used to guide the aperture warping. An in-house deformable image registration software was developed to automatically trigger the registration once new target image was acquired and send the computed deformation to the DMLC tracking software. Because the registration speed is not fast enough to implement the experiment in real-time manner, the phantom deformation only proceeded to the next position until registration of the current deformation position was completed. The deformation tracking accuracy was evaluated by a geometric target coverage metric defined as the sum of the area incorrectly outside and inside the ideal aperture. The individual contributions from the deformable registration algorithm and the finite leaf width to the tracking uncertainty were analyzed. Clinical proof-of-principle experiment of deformation tracking using previously acquired MR images of a lung cancer patient was implemented to represent the MRI-Linac environment. Intensity-modulated radiation therapy (IMRT) treatment delivered with enabled deformation tracking was simulated and demonstrated. Results: The first

Numerical study of suspensions of deformable particles.

NASA Astrophysics Data System (ADS)

Brandt, Luca; Rosti, Marco Edoardo

2017-11-01

We consider a model non-Newtonian fluid consisting of a suspension of deformable particles in a Newtonian solvent. Einstein showed in his pioneering work that the relative increase in effective viscosity is a linear function of the particle volume fraction for dilute suspensions of rigid particles. Inertia has been shown to introduce deviations from the behaviour predicted by the different empirical fits, an effect that can be related to an increase of the effective volume fraction. We here focus on the effect of elasticity, i.e. visco-elastic deformable particles. To tackle the problem at hand, we perform three-dimensional Direct Numerical Simulation of a plane Couette flow with a suspension of neutrally buoyant deformable viscous hyper-elastic particles. We show that elasticity produces a shear-thinning effect in elastic suspensions (in comparison to rigid ones) and that it can be understood in terms of a reduction of the effective volume fraction of the suspension. The deformation modifies the particle motion reducing the level of mutual interaction. Normal stress differences will also be considered. European Research Council, Grant No. ERC-2013-CoG- 616186, TRITOS; SNIC (the Swedish National Infrastructure for Computing).

Personal recognition using hand shape and texture.

PubMed

Kumar, Ajay; Zhang, David

2006-08-01

This paper proposes a new bimodal biometric system using feature-level fusion of hand shape and palm texture. The proposed combination is of significance since both the palmprint and hand-shape images are proposed to be extracted from the single hand image acquired from a digital camera. Several new hand-shape features that can be used to represent the hand shape and improve the performance are investigated. The new approach for palmprint recognition using discrete cosine transform coefficients, which can be directly obtained from the camera hardware, is demonstrated. None of the prior work on hand-shape or palmprint recognition has given any attention on the critical issue of feature selection. Our experimental results demonstrate that while majority of palmprint or hand-shape features are useful in predicting the subjects identity, only a small subset of these features are necessary in practice for building an accurate model for identification. The comparison and combination of proposed features is evaluated on the diverse classification schemes; naive Bayes (normal, estimated, multinomial), decision trees (C4.5, LMT), k-NN, SVM, and FFN. Although more work remains to be done, our results to date indicate that the combination of selected hand-shape and palmprint features constitutes a promising addition to the biometrics-based personal recognition systems.

Mechanical Deformation Mechanisms and Properties of Prion Fibrils Probed by Atomistic Simulations

NASA Astrophysics Data System (ADS)

Choi, Bumjoon; Kim, Taehee; Ahn, Eue Soo; Lee, Sang Woo; Eom, Kilho

2017-03-01

Prion fibrils, which are a hallmark for neurodegenerative diseases, have recently been found to exhibit the structural diversity that governs disease pathology. Despite our recent finding concerning the role of the disease-specific structure of prion fibrils in determining their elastic properties, the mechanical deformation mechanisms and fracture properties of prion fibrils depending on their structures have not been fully characterized. In this work, we have studied the tensile deformation mechanisms of prion and non-prion amyloid fibrils by using steered molecular dynamics simulations. Our simulation results show that the elastic modulus of prion fibril, which is formed based on left-handed β-helical structure, is larger than that of non-prion fibril constructed based on right-handed β-helix. However, the mechanical toughness of prion fibril is found to be less than that of non-prion fibril, which indicates that infectious prion fibril is more fragile than non-infectious (non-prion) fibril. Our study sheds light on the role of the helical structure of amyloid fibrils, which is related to prion infectivity, in determining their mechanical deformation mechanisms and properties.

Deformations of super Riemann surfaces

NASA Astrophysics Data System (ADS)

Ninnemann, Holger

1992-11-01

Two different approaches to (Kostant-Leites-) super Riemann surfaces are investigated. In the local approach, i.e. glueing open superdomains by superconformal transition functions, deformations of the superconformal structure are discussed. On the other hand, the representation of compact super Riemann surfaces of genus greater than one as a fundamental domain in the Poincaré upper half-plane provides a simple description of super Laplace operators acting on automorphic p-forms. Considering purely odd deformations of super Riemann surfaces, the number of linear independent holomorphic sections of arbitrary holomorphic line bundles will be shown to be independent of the odd moduli, leading to a simple proof of the Riemann-Roch theorem for compact super Riemann surfaces. As a further consequence, the explicit connections between determinants of super Laplacians and Selberg's super zeta functions can be determined, allowing to calculate at least the 2-loop contribution to the fermionic string partition function.

A biometric authentication model using hand gesture images.

PubMed

Fong, Simon; Zhuang, Yan; Fister, Iztok; Fister, Iztok

2013-10-30

A novel hand biometric authentication method based on measurements of the user's stationary hand gesture of hand sign language is proposed. The measurement of hand gestures could be sequentially acquired by a low-cost video camera. There could possibly be another level of contextual information, associated with these hand signs to be used in biometric authentication. As an analogue, instead of typing a password 'iloveu' in text which is relatively vulnerable over a communication network, a signer can encode a biometric password using a sequence of hand signs, 'i' , 'l' , 'o' , 'v' , 'e' , and 'u'. Subsequently the features from the hand gesture images are extracted which are integrally fuzzy in nature, to be recognized by a classification model for telling if this signer is who he claimed himself to be, by examining over his hand shape and the postures in doing those signs. It is believed that everybody has certain slight but unique behavioral characteristics in sign language, so are the different hand shape compositions. Simple and efficient image processing algorithms are used in hand sign recognition, including intensity profiling, color histogram and dimensionality analysis, coupled with several popular machine learning algorithms. Computer simulation is conducted for investigating the efficacy of this novel biometric authentication model which shows up to 93.75% recognition accuracy.

Real-Time Classification of Hand Motions Using Ultrasound Imaging of Forearm Muscles.

PubMed

Akhlaghi, Nima; Baker, Clayton A; Lahlou, Mohamed; Zafar, Hozaifah; Murthy, Karthik G; Rangwala, Huzefa S; Kosecka, Jana; Joiner, Wilsaan M; Pancrazio, Joseph J; Sikdar, Siddhartha

2016-08-01

Surface electromyography (sEMG) has been the predominant method for sensing electrical activity for a number of applications involving muscle-computer interfaces, including myoelectric control of prostheses and rehabilitation robots. Ultrasound imaging for sensing mechanical deformation of functional muscle compartments can overcome several limitations of sEMG, including the inability to differentiate between deep contiguous muscle compartments, low signal-to-noise ratio, and lack of a robust graded signal. The objective of this study was to evaluate the feasibility of real-time graded control using a computationally efficient method to differentiate between complex hand motions based on ultrasound imaging of forearm muscles. Dynamic ultrasound images of the forearm muscles were obtained from six able-bodied volunteers and analyzed to map muscle activity based on the deformation of the contracting muscles during different hand motions. Each participant performed 15 different hand motions, including digit flexion, different grips (i.e., power grasp and pinch grip), and grips in combination with wrist pronation. During the training phase, we generated a database of activity patterns corresponding to different hand motions for each participant. During the testing phase, novel activity patterns were classified using a nearest neighbor classification algorithm based on that database. The average classification accuracy was 91%. Real-time image-based control of a virtual hand showed an average classification accuracy of 92%. Our results demonstrate the feasibility of using ultrasound imaging as a robust muscle-computer interface. Potential clinical applications include control of multiarticulated prosthetic hands, stroke rehabilitation, and fundamental investigations of motor control and biomechanics.

Toe-to-hand transfer: Evolving Indications and Relevant Outcomes

PubMed Central

Waljee, Jennifer F.; Chung, Kevin C.

2014-01-01

In the late 19th century, the first toe to hand transfer was performed in Vienna, Switzerland as a staged procedure by Nicolandi.(1) Since that time, the advent of microsurgery has revolutionized toe to hand transfers. In 1966, Buncke performed the first microvascular toe to thumb transfer in a rhesus monkey.(2) The first toe to thumb transfer using microsurgical techniques in humans was performed by Cobbett in 1969, followed shortly thereafter by the first transfer of a second toe to the thumb position.(3,4) Today, due to expanding microsurgical techniques and surgeon innovation, the indications and techniques for toe-to-hand transfer procedures continue to evolve and now encompass patients with a variety of acquired and congenital hand defects.(5) PMID:23790426

Reconstruction of bilateral tibial aplasia and split hand-foot syndrome in a father and daughter.

PubMed

Al Kaissi, Ali; Ganger, Rudolf; Klaushofer, Klaus; Grill, Franz

2014-01-01

Tibial aplasia is of heterogeneous aetiology, the majority of reports are sporadic. We describe the reconstruction procedures in two subjects - a daughter and father manifested autosomal dominant (AD) inheritance of the bilateral tibial aplasia and split hand-foot syndrome. Reconstruction of these patients required multiple surgical procedures and orthoprosthesis was mandatory. The main goal of treatment was to achieve walking. Stabilization of the ankle joint by fibular-talar-chondrodesis on both sides, followed by bilateral Brown-procedure at the knee joint level has been applied accordingly. The outcome was with improved function of the deformed limbs and walking was achieved with simultaneous designation of orthotic fitting. This is the first study encompassing the diagnosis and management of a father and daughter with bilateral tibial aplasia associated with variable split hand/foot deformity without foot ablation. Our patients showed the typical AD pattern of inheritance of split-hand/foot and tibial aplasia.

Deformable Medical Image Registration: A Survey

PubMed Central

Sotiras, Aristeidis; Davatzikos, Christos; Paragios, Nikos

2013-01-01

Deformable image registration is a fundamental task in medical image processing. Among its most important applications, one may cite: i) multi-modality fusion, where information acquired by different imaging devices or protocols is fused to facilitate diagnosis and treatment planning; ii) longitudinal studies, where temporal structural or anatomical changes are investigated; and iii) population modeling and statistical atlases used to study normal anatomical variability. In this paper, we attempt to give an overview of deformable registration methods, putting emphasis on the most recent advances in the domain. Additional emphasis has been given to techniques applied to medical images. In order to study image registration methods in depth, their main components are identified and studied independently. The most recent techniques are presented in a systematic fashion. The contribution of this paper is to provide an extensive account of registration techniques in a systematic manner. PMID:23739795

Multiscale deformation behavior for multilayered steel by in-situ FE-SEM

NASA Astrophysics Data System (ADS)

Tanaka, Y.; Kishimoto, S.; Yin, F.; Kobayashi, M.; Tomimatsu, T.; Kagawa, K.

2010-03-01

The multi-scale deformation behavior of multi-layered steel during tensile loading was investigated by in-situ FE-SEM observation coupled with multi-scale pattern. The material used was multi-layered steel sheet consisting of martensitic and austenitic stainless steel layers. Prior to in-situ tensile testing, the multi-scale pattern combined with a grid and random dots were fabricated by electron beam lithography on the polished surface in the area of 1 mm2 to facilitate direct observation of multi-scale deformation. Both of the grids with pitches of 10 μm and a random speckle pattern ranging from 200 nm to a few μm sizes were drawn onto the specimen surface at same location. The electron moiré method was applied to measure the strain distribution in the deformed specimens at a millimeter scale and digital images correlation method was applied to measure the in-plane deformation and strain distribution at a micron meter scale acquired before and after at various increments of straining. The results showed that the plastic deformation in the austenitic stainless steel layer was larger than the martensitic steel layer at millimeter scale. However, heterogeneous intrinsic grain-scale plastic deformation was clearly observed and it increased with increasing the plastic deformation.

Restoration of the central slip in congenital form of boutonniere deformity: case report.

PubMed

Kim, Jong-Pil; Go, Jai-Hyang; Hwang, Chang-Hwan; Shin, Won-Jeong

2014-10-01

We present a case of a congenital form of a boutonniere deformity involving both little fingers with a poorly differentiated extensor mechanism and the absence of the tendinous attachment on the dorsal aspect of the middle phalanx. This complex deformity was evaluated histologically followed by successful reconstruction of the central slip. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Interseismic Deformation along the Red River Fault from InSAR Measurements

NASA Astrophysics Data System (ADS)

Chen, J.; Li, Z.; Clarke, P. J.

2017-12-01

The Red River Fault (RRF) zone is a profound geological discontinuity separating South China from Indochina. Right lateral movements along this >900 km fault are considered to accommodate the extrusion of SE China. Crustal deformation monitoring at high resolution is the key to understand the present-day mode of deformation in this zone and its interaction with the adjacent regions. This is the first study to measure the interseismic deformation of the entire fault with ALOS-1/2 and Sentinel-1 observations. Nine ascending tracks of ALOS-1 data between 2007 and 2011 are collected from the Alaska Satellite Facility (ASF), four descending tracks of Sentinel-1 data are acquired every 24 days since October 2014, and ALOS-2 data are being systematically acquired since 2014. The long wavelength (L-band) of ALOS-1/2 and short temporal baseline of Sentinel-1 ensure good coherence to overcome the limitations of heavy vegetation and variable climate in the region. Stacks of interferograms are generated by our automatic processing chain based on the InSAR Scientific Computing Environment (ISCE) software, ionospheric errors are estimated and corrected using the split-spectrum method (Fattahi et al., IEEE Trans. Geosci. Remote Sens., 2017) and the tropospheric delays are calibrated using the Generic Atmospheric Correction Online Service for InSAR (GACOS: http://ceg-research.ncl.ac.uk/v2/gacos) with high-resolution ECMWF products (Yu et al., J. Geophys. Res., 2017). Time series analysis is performed to determine the interseismic deformation rate of the RRF using the in-house InSAR time series with atmospheric estimation model (InSAR TS + AEM) package based on the Small Baseline Subset (SBAS) algorithm. Our results reveal the decrease of slip rate from north to south. We map the interseismic strain rate field to characterize the deformation patterns and seismic hazard throughout the RRF zone.

On the feasibility of interoperable schemes in hand biometrics.

PubMed

Morales, Aythami; González, Ester; Ferrer, Miguel A

2012-01-01

Personal recognition through hand-based biometrics has attracted the interest of many researchers in the last twenty years. A significant number of proposals based on different procedures and acquisition devices have been published in the literature. However, comparisons between devices and their interoperability have not been thoroughly studied. This paper tries to fill this gap by proposing procedures to improve the interoperability among different hand biometric schemes. The experiments were conducted on a database made up of 8,320 hand images acquired from six different hand biometric schemes, including a flat scanner, webcams at different wavelengths, high quality cameras, and contactless devices. Acquisitions on both sides of the hand were included. Our experiment includes four feature extraction methods which determine the best performance among the different scenarios for two of the most popular hand biometrics: hand shape and palm print. We propose smoothing techniques at the image and feature levels to reduce interdevice variability. Results suggest that comparative hand shape offers better performance in terms of interoperability than palm prints, but palm prints can be more effective when using similar sensors.

On the Feasibility of Interoperable Schemes in Hand Biometrics

PubMed Central

Morales, Aythami; González, Ester; Ferrer, Miguel A.

2012-01-01

Personal recognition through hand-based biometrics has attracted the interest of many researchers in the last twenty years. A significant number of proposals based on different procedures and acquisition devices have been published in the literature. However, comparisons between devices and their interoperability have not been thoroughly studied. This paper tries to fill this gap by proposing procedures to improve the interoperability among different hand biometric schemes. The experiments were conducted on a database made up of 8,320 hand images acquired from six different hand biometric schemes, including a flat scanner, webcams at different wavelengths, high quality cameras, and contactless devices. Acquisitions on both sides of the hand were included. Our experiment includes four feature extraction methods which determine the best performance among the different scenarios for two of the most popular hand biometrics: hand shape and palm print. We propose smoothing techniques at the image and feature levels to reduce interdevice variability. Results suggest that comparative hand shape offers better performance in terms of interoperability than palm prints, but palm prints can be more effective when using similar sensors. PMID:22438714

An image-guided tool to prevent hospital acquired infections

NASA Astrophysics Data System (ADS)

Nagy, Melinda; Szilágyi, László; Lehotsky, Ákos; Haidegger, Tamás; Benyó, Balázs

2011-03-01

Hospital Acquired Infections (HAI) represent the fourth leading cause of death in the United States, and claims hundreds of thousands of lives annually in the rest of the world. This paper presents a novel low-cost mobile device|called Stery-Hand|that helps to avoid HAI by improving hand hygiene control through providing an objective evaluation of the quality of hand washing. The use of the system is intuitive: having performed hand washing with a soap mixed with UV re ective powder, the skin appears brighter in UV illumination on the disinfected surfaces. Washed hands are inserted into the Stery-Hand box, where a digital image is taken under UV lighting. Automated image processing algorithms are employed in three steps to evaluate the quality of hand washing. First, the contour of the hand is extracted in order to distinguish the hand from the background. Next, a semi-supervised clustering algorithm classies the pixels of the hand into three groups, corresponding to clean, partially clean and dirty areas. The clustering algorithm is derived from the histogram-based quick fuzzy c-means approach, using a priori information extracted from reference images, evaluated by experts. Finally, the identied areas are adjusted to suppress shading eects, and quantied in order to give a verdict on hand disinfection quality. The proposed methodology was validated through tests using hundreds of images recorded in our laboratory. The proposed system was found robust and accurate, producing correct estimation for over 98% of the test cases. Stery-Hand may be employed in general practice, and it may also serve educational purposes.

Toward the development of intrafraction tumor deformation tracking using a dynamic multi-leaf collimator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ge, Yuanyuan; O’Brien, Ricky T.; Shieh, Chun-Chien

Purpose: Intrafraction deformation limits targeting accuracy in radiotherapy. Studies show tumor deformation of over 10 mm for both single tumor deformation and system deformation (due to differential motion between primary tumors and involved lymph nodes). Such deformation cannot be adapted to with current radiotherapy methods. The objective of this study was to develop and experimentally investigate the ability of a dynamic multi-leaf collimator (DMLC) tracking system to account for tumor deformation. Methods: To compensate for tumor deformation, the DMLC tracking strategy is to warp the planned beam aperture directly to conform to the new tumor shape based on real timemore » tumor deformation input. Two deformable phantoms that correspond to a single tumor and a tumor system were developed. The planar deformations derived from the phantom images in beam's eye view were used to guide the aperture warping. An in-house deformable image registration software was developed to automatically trigger the registration once new target image was acquired and send the computed deformation to the DMLC tracking software. Because the registration speed is not fast enough to implement the experiment in real-time manner, the phantom deformation only proceeded to the next position until registration of the current deformation position was completed. The deformation tracking accuracy was evaluated by a geometric target coverage metric defined as the sum of the area incorrectly outside and inside the ideal aperture. The individual contributions from the deformable registration algorithm and the finite leaf width to the tracking uncertainty were analyzed. Clinical proof-of-principle experiment of deformation tracking using previously acquired MR images of a lung cancer patient was implemented to represent the MRI-Linac environment. Intensity-modulated radiation therapy (IMRT) treatment delivered with enabled deformation tracking was simulated and demonstrated. Results: The first

SU-F-I-50: Finite Element-Based Deformable Image Registration of Lung and Heart

DOE Office of Scientific and Technical Information (OSTI.GOV)

Penjweini, R; Kim, M; Zhu, T

Purpose: Photodynamic therapy (PDT) is used after surgical resection to treat the microscopic disease for malignant pleural mesothelioma and to increase survival rates. Although accurate light delivery is imperative to PDT efficacy, the deformation of the pleural volume during the surgery impacts the delivered light dose. To facilitate treatment planning, we use a finite-element-based (FEM) deformable image registration to quantify the anatomical variation of lung and heart volumes between CT pre-(or post-) surgery and surface contours obtained during PDT using an infrared camera-based navigation system (NDI). Methods: NDI is used during PDT to obtain the information of the cumulative lightmore » fluence on every cavity surface point that is being treated. A wand, comprised of a modified endotrachial tube filled with Intralipid and an optical fiber inside the tube, is used to deliver the light during PDT. The position of the treatment is tracked using an attachment with nine reflective passive markers that are seen by the NDI system. Then, the position points are plotted as three-dimensional volume of the pleural cavity using Matlab and Meshlab. A series of computed tomography (CT) scans of the lungs and heart, in the same patient, are also acquired before and after the surgery. The NDI and CT contours are imported into COMSOL Multiphysics, where the FEM-based deformable image registration is obtained. The NDI and CT contours acquired during and post-PDT are considered as the reference, and the Pre-PDT CT contours are used as the target, which will be deformed. Results: Anatomical variation of the lung and heart volumes, taken at different times from different imaging devices, was determined by using our model. The resulting three-dimensional deformation map along x, y and z-axes was obtained. Conclusion: Our model fuses images acquired by different modalities and provides insights into the variation in anatomical structures over time.« less

Right-Handed Neutrinos and the 2 TeV $W'$ Boson

DOE PAGES

Coloma, Pilar; Dobrescu, Bogdan A.; Lopez-Pavon, Jacobo

2015-12-30

The CMS e +e -jj events of invariant mass near 2 TeV are consistent with a W' boson decaying into an electron and a right-handed neutrino whose TeV-scale mass is of the Dirac type. We show that the Dirac partner of the right-handed electron-neutrino can be the right-handed tau-neutrino. Furthermore, a prediction of this model is that the sum of the τ +e +jj and τ -e -jj signal cross sections equals twice that for e +e -jj. The Standard Model neutrinos acquire Majorana masses and mixings compatible with neutrino oscillation data.

Quantitative assessment of soft tissue deformation using digital speckle pattern interferometry: studies on phantom breast models.

PubMed

Karuppanan, Udayakumar; Unni, Sujatha Narayanan; Angarai, Ganesan R

2017-01-01

Assessment of mechanical properties of soft matter is a challenging task in a purely noninvasive and noncontact environment. As tissue mechanical properties play a vital role in determining tissue health status, such noninvasive methods offer great potential in framing large-scale medical screening strategies. The digital speckle pattern interferometry (DSPI)-based image capture and analysis system described here is capable of extracting the deformation information from a single acquired fringe pattern. Such a method of analysis would be required in the case of the highly dynamic nature of speckle patterns derived from soft tissues while applying mechanical compression. Soft phantoms mimicking breast tissue optical and mechanical properties were fabricated and tested in the DSPI out of plane configuration set up. Hilbert transform (HT)-based image analysis algorithm was developed to extract the phase and corresponding deformation of the sample from a single acquired fringe pattern. The experimental fringe contours were found to correlate with numerically simulated deformation patterns of the sample using Abaqus finite element analysis software. The extracted deformation from the experimental fringe pattern using the HT-based algorithm is compared with the deformation value obtained using numerical simulation under similar conditions of loading and the results are found to correlate with an average %error of 10. The proposed method is applied on breast phantoms fabricated with included subsurface anomaly mimicking cancerous tissue and the results are analyzed.

A Microfluidic Technique to Probe Cell Deformability

PubMed Central

Hoelzle, David J.; Varghese, Bino A.; Chan, Clara K.; Rowat, Amy C.

2014-01-01

Here we detail the design, fabrication, and use of a microfluidic device to evaluate the deformability of a large number of individual cells in an efficient manner. Typically, data for ~102 cells can be acquired within a 1 hr experiment. An automated image analysis program enables efficient post-experiment analysis of image data, enabling processing to be complete within a few hours. Our device geometry is unique in that cells must deform through a series of micron-scale constrictions, thereby enabling the initial deformation and time-dependent relaxation of individual cells to be assayed. The applicability of this method to human promyelocytic leukemia (HL-60) cells is demonstrated. Driving cells to deform through micron-scale constrictions using pressure-driven flow, we observe that human promyelocytic (HL-60) cells momentarily occlude the first constriction for a median time of 9.3 msec before passaging more quickly through the subsequent constrictions with a median transit time of 4.0 msec per constriction. By contrast, all-trans retinoic acid-treated (neutrophil-type) HL-60 cells occlude the first constriction for only 4.3 msec before passaging through the subsequent constrictions with a median transit time of 3.3 msec. This method can provide insight into the viscoelastic nature of cells, and ultimately reveal the molecular origins of this behavior. PMID:25226269

Ultra fine grained Ti prepared by severe plastic deformation

NASA Astrophysics Data System (ADS)

Lukáč, F.; Čížek, J.; Knapp, J.; Procházka, I.; Zháňal, P.; Islamgaliev, R. K.

2016-01-01

The positron annihilation spectroscopy was employed for characterisation of defects in pure Ti with ultra fine grained (UFG) structure. UFG Ti samples were prepared by two techniques based on severe plastic deformation (SPD): (i) high pressure torsion (HPT) and (ii) equal channel angular pressing (ECAP). Although HPT is the most efficient technique for grain refinement, the size of HPT-deformed specimens is limited. On the other hand, ECAP is less efficient in grain refinement but enables to produce larger samples more suitable for industrial applications. Characterisation of defects by positron annihilation spectroscopy was accompanied by hardness testing in order to monitor the development of mechanical properties of UFG Ti.

Infant Hand Preference and the Development of Cognitive Abilities

PubMed Central

Michel, George F.; Campbell, Julie M.; Marcinowski, Emily C.; Nelson, Eliza L.; Babik, Iryna

2016-01-01

Hand preference develops in the first two postnatal years with nearly half of infants exhibiting a consistent early preference for acquiring objects. Others exhibit a more variable developmental trajectory but by the end of their second postnatal year, most exhibit a consistent hand preference for role-differentiated bimanual manipulation. According to some forms of embodiment theory, these differences in hand use patterns should influence the way children interact with their environments, which, in turn, should affect the structure and function of brain development. Such early differences in brain development should result in different trajectories of psychological development. We present evidence that children with consistent early hand preferences exhibit advanced patterns of cognitive development as compared to children who develop a hand preference later. Differences in the developmental trajectory of hand preference are predictive of developmental differences in language, object management skills, and tool-use skills. As predicted by Casasanto’s body-specificity hypothesis, infants with different hand preferences proceed along different developmental pathways of cognitive functioning. PMID:27047431

A biometric authentication model using hand gesture images

PubMed Central

2013-01-01

A novel hand biometric authentication method based on measurements of the user’s stationary hand gesture of hand sign language is proposed. The measurement of hand gestures could be sequentially acquired by a low-cost video camera. There could possibly be another level of contextual information, associated with these hand signs to be used in biometric authentication. As an analogue, instead of typing a password ‘iloveu’ in text which is relatively vulnerable over a communication network, a signer can encode a biometric password using a sequence of hand signs, ‘i’ , ‘l’ , ‘o’ , ‘v’ , ‘e’ , and ‘u’. Subsequently the features from the hand gesture images are extracted which are integrally fuzzy in nature, to be recognized by a classification model for telling if this signer is who he claimed himself to be, by examining over his hand shape and the postures in doing those signs. It is believed that everybody has certain slight but unique behavioral characteristics in sign language, so are the different hand shape compositions. Simple and efficient image processing algorithms are used in hand sign recognition, including intensity profiling, color histogram and dimensionality analysis, coupled with several popular machine learning algorithms. Computer simulation is conducted for investigating the efficacy of this novel biometric authentication model which shows up to 93.75% recognition accuracy. PMID:24172288

A new approach to hand-based authentication

NASA Astrophysics Data System (ADS)

Amayeh, G.; Bebis, G.; Erol, A.; Nicolescu, M.

2007-04-01

Hand-based authentication is a key biometric technology with a wide range of potential applications both in industry and government. Traditionally, hand-based authentication is performed by extracting information from the whole hand. To account for hand and finger motion, guidance pegs are employed to fix the position and orientation of the hand. In this paper, we consider a component-based approach to hand-based verification. Our objective is to investigate the discrimination power of different parts of the hand in order to develop a simpler, faster, and possibly more accurate and robust verification system. Specifically, we propose a new approach which decomposes the hand in different regions, corresponding to the fingers and the back of the palm, and performs verification using information from certain parts of the hand only. Our approach operates on 2D images acquired by placing the hand on a flat lighting table. Using a part-based representation of the hand allows the system to compensate for hand and finger motion without using any guidance pegs. To decompose the hand in different regions, we use a robust methodology based on morphological operators which does not require detecting any landmark points on the hand. To capture the geometry of the back of the palm and the fingers in suffcient detail, we employ high-order Zernike moments which are computed using an effcient methodology. The proposed approach has been evaluated on a database of 100 subjects with 10 images per subject, illustrating promising performance. Comparisons with related approaches using the whole hand for verification illustrate the superiority of the proposed approach. Moreover, qualitative comparisons with state-of-the-art approaches indicate that the proposed approach has comparable or better performance.

Cytomegalovirus Survival and Transferability and the Effectiveness of Common Hand-Washing Agents against Cytomegalovirus on Live Human Hands

PubMed Central

Stowell, Jennifer D.; Forlin-Passoni, Daniela; Radford, Kay; Bate, Sheri L.; Dollard, Sheila C.; Bialek, Stephanie R.; Cannon, Michael J.

2014-01-01

Congenital cytomegalovirus (CMV) transmission can occur when women acquire CMV while pregnant. Infection control guidelines may reduce risk for transmission. We studied the duration of CMV survival after application of bacteria to the hands and after transfer from the hands to surfaces and the effectiveness of cleansing with water, regular and antibacterial soaps, sanitizer, and diaper wipes. Experiments used CMV AD169 in saliva at initial titers of 1 × 105 infectious particles/ml. Samples from hands or surfaces (points between 0 and 15 min) were placed in culture and observed for at least 2 weeks. Samples were also tested using CMV real-time PCR. After application of bacteria to the hands, viable CMV was recovered from 17/20 swabs at 0 min, 18/20 swabs at 1 min, 5/20 swabs at 5 min, and 4/20 swabs at 15 min. After transfer, duration of survival was at least 15 min on plastic (1/2 swabs), 5 min on crackers and glass (3/4 swabs), and 1 min or less on metal and cloth (3/4 swabs); no viable virus was collected from wood, rubber, or hands. After cleansing, no viable virus was recovered using water (0/22), plain soap (0/20), antibacterial soap (0/20), or sanitizer (0/22). Viable CMV was recovered from 4/20 hands 10 min after diaper wipe cleansing. CMV remains viable on hands for sufficient times to allow transmission. CMV may be transferred to surfaces with reduced viability. Hand-cleansing methods were effective at eliminating viable CMV from hands. PMID:24185855

Cytomegalovirus survival and transferability and the effectiveness of common hand-washing agents against cytomegalovirus on live human hands.

PubMed

Stowell, Jennifer D; Forlin-Passoni, Daniela; Radford, Kay; Bate, Sheri L; Dollard, Sheila C; Bialek, Stephanie R; Cannon, Michael J; Schmid, D Scott

2014-01-01

Congenital cytomegalovirus (CMV) transmission can occur when women acquire CMV while pregnant. Infection control guidelines may reduce risk for transmission. We studied the duration of CMV survival after application of bacteria to the hands and after transfer from the hands to surfaces and the effectiveness of cleansing with water, regular and antibacterial soaps, sanitizer, and diaper wipes. Experiments used CMV AD169 in saliva at initial titers of 1 × 10(5) infectious particles/ml. Samples from hands or surfaces (points between 0 and 15 min) were placed in culture and observed for at least 2 weeks. Samples were also tested using CMV real-time PCR. After application of bacteria to the hands, viable CMV was recovered from 17/20 swabs at 0 min, 18/20 swabs at 1 min, 5/20 swabs at 5 min, and 4/20 swabs at 15 min. After transfer, duration of survival was at least 15 min on plastic (1/2 swabs), 5 min on crackers and glass (3/4 swabs), and 1 min or less on metal and cloth (3/4 swabs); no viable virus was collected from wood, rubber, or hands. After cleansing, no viable virus was recovered using water (0/22), plain soap (0/20), antibacterial soap (0/20), or sanitizer (0/22). Viable CMV was recovered from 4/20 hands 10 min after diaper wipe cleansing. CMV remains viable on hands for sufficient times to allow transmission. CMV may be transferred to surfaces with reduced viability. Hand-cleansing methods were effective at eliminating viable CMV from hands.

Hand dermatitis/eczema: current management strategy.

PubMed

Sehgal, Virendra N; Srivastava, Govind; Aggarwal, Ashok K; Sharma, Alpna D

2010-07-01

Ever since its inception a couple of centuries ago, hand dermatitis/eczema has been in the reckoning. Idiosyncrasies continued to loom large thereafter, till it acquired its appropriate position. Dermatitis/eczema are synonymous, often used to indicate a polymorphic pattern of the inflammation of the skin, characterized by pruritus, erythema and vesiculation. A spectrum delineated into acute sub-acute and chronic dermatitis of the hands. Pompholyx, recurrent focal palmer peeling, ring, wear and tear and fingertip eczema, apron, discoid eczema, chronic acral dermatitis, gut and patchy papulosquamous eczema are its clinical variants. Occupational dermatitis/eczema may be contributory. Etiological definitions are clinched by detailed history of exogenous and endogenous factors. However, scientific confirmation of the entity is through patch testing by using available antigens.

Effect of deformations on the compactness of odd-Z superheavy nuclei formed in cold and hot fusion reactions

NASA Astrophysics Data System (ADS)

Kaur, Gurjit; Sandhu, Kirandeep; Sharma, Manoj K.

2018-03-01

Using the extended fragmentation theory, the compactness of hot and cold fusion reactions is analyzed for odd-Z nuclei ranging Z = 105- 117. The calculations for the present work are carried out at T = 0MeV and ℓ = 0 ħ, as the temperature and angular momentum effects remain silent while addressing the orientation degree of freedom (i.e. compact angle configuration). In the hot fusion, 48Ca (spherical) + actinide (prolate) reaction, the non-equatorial compact (nec) shape is obtained for Z = 113 nucleus. On the other hand, Z > 113 nuclei favor equatorial compact (ec) configuration. The distribution of barrier height (VB) illustrate that the ec-shape is obtained when the magnitude of quadrupole deformation of the nucleus is higher than the hexadecupole deformation. In other words, negligible or small -ve β4-deformations support ec configurations. On the other hand, large (+ve) magnitude of the β4-deformation suggests that the configuration appears for compact angle θc < 90 °, leading to nec structure. Similar deformation effects are observed for Bi-induced reactions, in which not belly-to-belly compact (nbbc) configurations are seen at θc = 42 °. In addition to the effect of β2 and β4-deformations, the exclusive role of octupole deformations (β3) is also analyzed. The β3-deformations do not follow the reflection symmetry as that of β2 and β4, leading to the possible occurrence of compact configuration within 0° to 180° angular range.

Strength and Deformability of Light-toned Layered Deposits Observed by MER Opportunity: Eagle to Erebus Craters

NASA Astrophysics Data System (ADS)

Okubo, C. H.; Schultz, R. A.; Nahm, A. L.

2007-07-01

The strength and deformability of light-toned layered deposits are estimated based on measurements of porosity from Microscopic Imager data acquired by MER Opportunity during its traverse from Eagle Crater to Erebus Crater.

Spatial carrier color digital speckle pattern interferometry for absolute three-dimensional deformation measurement

NASA Astrophysics Data System (ADS)

Gao, Xinya; Wang, Yonghong; Li, Junrui; Dan, Xizuo; Wu, Sijin; Yang, Lianxiang

2017-06-01

It is difficult to measure absolute three-dimensional deformation using traditional digital speckle pattern interferometry (DSPI) when the boundary condition of an object being tested is not exactly given. In practical applications, the boundary condition cannot always be specifically provided, limiting the use of DSPI in real-world applications. To tackle this problem, a DSPI system that is integrated by the spatial carrier method and a color camera has been established. Four phase maps are obtained simultaneously by spatial carrier color-digital speckle pattern interferometry using four speckle interferometers with different illumination directions. One out-of-plane and two in-plane absolute deformations can be acquired simultaneously without knowing the boundary conditions using the absolute deformation extraction algorithm based on four phase maps. Finally, the system is proved by experimental results through measurement of the deformation of a flat aluminum plate with a groove.

Quantitative assessment of soft tissue deformation using digital speckle pattern interferometry: studies on phantom breast models

PubMed Central

Karuppanan, Udayakumar; Unni, Sujatha Narayanan; Angarai, Ganesan R.

2017-01-01

Abstract. Assessment of mechanical properties of soft matter is a challenging task in a purely noninvasive and noncontact environment. As tissue mechanical properties play a vital role in determining tissue health status, such noninvasive methods offer great potential in framing large-scale medical screening strategies. The digital speckle pattern interferometry (DSPI)–based image capture and analysis system described here is capable of extracting the deformation information from a single acquired fringe pattern. Such a method of analysis would be required in the case of the highly dynamic nature of speckle patterns derived from soft tissues while applying mechanical compression. Soft phantoms mimicking breast tissue optical and mechanical properties were fabricated and tested in the DSPI out of plane configuration set up. Hilbert transform (HT)-based image analysis algorithm was developed to extract the phase and corresponding deformation of the sample from a single acquired fringe pattern. The experimental fringe contours were found to correlate with numerically simulated deformation patterns of the sample using Abaqus finite element analysis software. The extracted deformation from the experimental fringe pattern using the HT-based algorithm is compared with the deformation value obtained using numerical simulation under similar conditions of loading and the results are found to correlate with an average %error of 10. The proposed method is applied on breast phantoms fabricated with included subsurface anomaly mimicking cancerous tissue and the results are analyzed. PMID:28180134

Micromechanisms of deformation in shales

NASA Astrophysics Data System (ADS)

Bonnelye, A.; Gharbi, H.; Hallais, S.; Dimanov, A.; Bornert, M.; Picard, D.; Mezni, M.; Conil, N.

2017-12-01

One of the envisaged solutions for nuclear wastes disposal is underground repository in shales. For this purpose, the Callovo Oxfordian (Cox) argillaceous formation is extensively studied. The hydro-mechanical behavior of the argillaceous rock is complex, like the multiphase and multi-scale structured material itself. The argilaceous matrix is composed of interstratified illite-smectite particles, it contains detritic quartz and calcite, accessory pyrite, and the rock porosity ranges from micrometre to nanometre scales. Besides the bedding anisotropy, structural variabilities exist at all scales, from the decametric-metric scales of the geological formation to the respectively millimetric and micrometric scales of the aggregates of particles and clay particles Our study aims at understanding the complex mechanisms which are activated at the micro-scale and are involved in the macroscopic inelastic deformation of such a complex material. Two sets of experiments were performed, at two scales on three bedding orientations (90°, 45° and 0°). The first set was dedicated to uniaxial deformation followed with an optical set-up with a pixel resolution of 0.55µm. These experiments allowed us to see the fracture propagation with different patterns depending on the bedding orientation. For the second set of experiments, an experimental protocol was developed in order to perform uniaxial deformation experiment at controlled displacement rate, inside an environmental scanning electron microscope (ESEM), under controlled relative humidity, in order to preserve as much as possible the natural state of saturation of shales. We aimed at characterizing the mechanical anisotropy and the mechanisms involved in the deformation, with an image resolution below the micormeter. The observed sample surfaces were polished by broad ion beam in order to reveal the fine microstructures of the argillaceous matrix. In both cases, digital images were acquired at different loading stages during

Superposed ruptile deformational events revealed by field and VOM structural analysis

NASA Astrophysics Data System (ADS)

Kumaira, Sissa; Guadagnin, Felipe; Keller Lautert, Maiara

2017-04-01

Virtual outcrop models (VOM) is becoming an important application in the analysis of geological structures due to the possibility of obtaining the geometry and in some cases kinematic aspects of analyzed structures in a tridimensional photorealistic space. These data are used to gain quantitative information on the deformational features which coupled with numeric models can assist in understands deformational processes. Old basement units commonly register superposed deformational events either ductile or ruptile along its evolution. The Porongos Belt, located at southern Brazil, have a complex deformational history registering at least five ductile and ruptile deformational events. In this study, we presents a structural analysis of a quarry in the Porongos Belt, coupling field and VOM structural information to understand process involved in the last two deformational events. Field information was acquired using traditional structural methods for analysis of ruptile structures, such as the descriptions, drawings, acquisition of orientation vectors and kinematic analysis. VOM was created from the image-based modeling method through photogrammetric data acquisition and orthorectification. Photogrammetric data acquisition was acquired using Sony a3500 camera and a total of 128 photographs were taken from ca. 10-20 m from the outcrop in different orientations. Thirty two control point coordinates were acquired using a combination of RTK dGPS surveying and total station work, providing a precision of few millimeters for x, y and z. Photographs were imported into the Photo Scan software to create a 3D dense point cloud from structure from-motion algorithm, which were triangulated and textured to generate the VOM. VOM was georreferenced (oriented and scaled) using the ground control points, and later analyzed in OpenPlot software to extract structural information. Data was imported in Wintensor software to obtain tensor orientations, and Move software to process and

A skeleton family generator via physics-based deformable models.

PubMed

Krinidis, Stelios; Chatzis, Vassilios

2009-01-01

This paper presents a novel approach for object skeleton family extraction. The introduced technique utilizes a 2-D physics-based deformable model that parameterizes the objects shape. Deformation equations are solved exploiting modal analysis, and proportional to model physical characteristics, a different skeleton is produced every time, generating, in this way, a family of skeletons. The theoretical properties and the experiments presented demonstrate that obtained skeletons match to hand-labeled skeletons provided by human subjects, even in the presence of significant noise and shape variations, cuts and tears, and have the same topology as the original skeletons. In particular, the proposed approach produces no spurious branches without the need of any known skeleton pruning method.

Image updating for brain deformation compensation in tumor resection

NASA Astrophysics Data System (ADS)

Fan, Xiaoyao; Ji, Songbai; Olson, Jonathan D.; Roberts, David W.; Hartov, Alex; Paulsen, Keith D.

2016-03-01

Preoperative magnetic resonance images (pMR) are typically used for intraoperative guidance in image-guided neurosurgery, the accuracy of which can be significantly compromised by brain deformation. Biomechanical finite element models (FEM) have been developed to estimate whole-brain deformation and produce model-updated MR (uMR) that compensates for brain deformation at different surgical stages. Early stages of surgery, such as after craniotomy and after dural opening, have been well studied, whereas later stages after tumor resection begins remain challenging. In this paper, we present a method to simulate tumor resection by incorporating data from intraoperative stereovision (iSV). The amount of tissue resection was estimated from iSV using a "trial-and-error" approach, and the cortical shift was measured from iSV through a surface registration method using projected images and an optical flow (OF) motion tracking algorithm. The measured displacements were employed to drive the biomechanical brain deformation model, and the estimated whole-brain deformation was subsequently used to deform pMR and produce uMR. We illustrate the method using one patient example. The results show that the uMR aligned well with iSV and the overall misfit between model estimates and measured displacements was 1.46 mm. The overall computational time was ~5 min, including iSV image acquisition after resection, surface registration, modeling, and image warping, with minimal interruption to the surgical flow. Furthermore, we compare uMR against intraoperative MR (iMR) that was acquired following iSV acquisition.

Electromyography data for non-invasive naturally-controlled robotic hand prostheses

PubMed Central

Atzori, Manfredo; Gijsberts, Arjan; Castellini, Claudio; Caputo, Barbara; Hager, Anne-Gabrielle Mittaz; Elsig, Simone; Giatsidis, Giorgio; Bassetto, Franco; Müller, Henning

2014-01-01

Recent advances in rehabilitation robotics suggest that it may be possible for hand-amputated subjects to recover at least a significant part of the lost hand functionality. The control of robotic prosthetic hands using non-invasive techniques is still a challenge in real life: myoelectric prostheses give limited control capabilities, the control is often unnatural and must be learned through long training times. Meanwhile, scientific literature results are promising but they are still far from fulfilling real-life needs. This work aims to close this gap by allowing worldwide research groups to develop and test movement recognition and force control algorithms on a benchmark scientific database. The database is targeted at studying the relationship between surface electromyography, hand kinematics and hand forces, with the final goal of developing non-invasive, naturally controlled, robotic hand prostheses. The validation section verifies that the data are similar to data acquired in real-life conditions, and that recognition of different hand tasks by applying state-of-the-art signal features and machine-learning algorithms is possible. PMID:25977804

Spinal deformities rehabilitation - state of the art review.

PubMed

Weiss, Hans-Rudolf

2010-12-24

Medical rehabilitation aims at an improvement in function, capacity and participation. For the rehabilitation of spinal deformities, the goal is to maintain function and prevent secondary symptoms in the short- and long-term. In patients with scoliosis, predictable signs and symptoms include pain and reduced pulmonary function. A Pub Med review was completed in order to reveal substantial evidence for inpatient rehabilitation as performed in Germany. No evidence has been found in general to support claims for actual inpatient rehabilitation programmes as used today. Nevertheless, as there is some evidence that inpatient rehabilitation may be beneficial to patients with spinal deformities complicated by certain additional conditions, the body of evidence there is for conservative treatment of spinal deformities has been reviewed in order to allow suggestions for outpatient conservative treatment and inpatient rehabilitation. Today, for both children and adolescents, we are able to offer intensive rehabilitation programmes lasting three to five days, which enable the patients to acquire the skills necessary to prevent postures fostering scoliosis in everyday life without missing too much of school teaching subjects at home. The secondary functional impairments adult scoliosis patients might have, as in the opinion of the author, still today require the time of 3-4 weeks in the clinical in-patient setting. Time to address psychosocial as well as somatic limitations, namely chronic pains and cardiorespiratory malfunction is needed to preserve the patients working capability in the long-term. Outpatient treatment/rehabilitation is sufficient for adolescents with spinal deformities.Inpatient rehabilitation is recommended for patients with spinal deformities and pain or severe restrictive ventilation disorder.

Dynamic Deformation Measurements of an Aeroelastic Semispan Model. [conducted in the Transonic Dynamics Tunnel at the NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Graves, Sharon S.; Burner, Alpheus W.; Edwards, John W.; Schuster, David M.

2001-01-01

The techniques used to acquire, reduce, and analyze dynamic deformation measurements of an aeroelastic semispan wind tunnel model are presented. Single-camera, single-view video photogrammetry (also referred to as videogrammetric model deformation, or VMD) was used to determine dynamic aeroelastic deformation of the semispan 'Models for Aeroelastic Validation Research Involving Computation' (MAVRIC) model in the Transonic Dynamics Tunnel at the NASA Langley Research Center. Dynamic deformation was determined from optical retroreflective tape targets at five semispan locations located on the wing from the root to the tip. Digitized video images from a charge coupled device (CCD) camera were recorded and processed to automatically determine target image plane locations that were then corrected for sensor, lens, and frame grabber spatial errors. Videogrammetric dynamic data were acquired at a 60-Hz rate for time records of up to 6 seconds during portions of this flutter/Limit Cycle Oscillation (LCO) test at Mach numbers from 0.3 to 0.96. Spectral analysis of the deformation data is used to identify dominant frequencies in the wing motion. The dynamic data will be used to separate aerodynamic and structural effects and to provide time history deflection data for Computational Aeroelasticity code evaluation and validation.

Optical dynamic deformation measurements at translucent materials.

PubMed

Philipp, Katrin; Koukourakis, Nektarios; Kuschmierz, Robert; Leithold, Christoph; Fischer, Andreas; Czarske, Jürgen

2015-02-15

Due to their high stiffness-to-weight ratio, glass fiber-reinforced polymers are an attractive material for rotors, e.g., in the aerospace industry. A fundamental understanding of the material behavior requires non-contact, in-situ dynamic deformation measurements. The high surface speeds and particularly the translucence of the material limit the usability of conventional optical measurement techniques. We demonstrate that the laser Doppler distance sensor provides a powerful and reliable tool for monitoring radial expansion at fast rotating translucent materials. We find that backscattering in material volume does not lead to secondary signals as surface scattering results in degradation of the measurement volume inside the translucent medium. This ensures that the acquired signal contains information of the rotor surface only, as long as the sample surface is rough enough. Dynamic deformation measurements of fast-rotating fiber-reinforced polymer composite rotors with surface speeds of more than 300 m/s underline the potential of the laser Doppler sensor.

Three-Dimensional Dynamic Deformation Measurements Using Stereoscopic Imaging and Digital Speckle Photography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prentice, H. J.; Proud, W. G.

2006-07-28

A technique has been developed to determine experimentally the three-dimensional displacement field on the rear surface of a dynamically deforming plate. The technique combines speckle analysis with stereoscopy, using a modified angular-lens method: this incorporates split-frame photography and a simple method by which the effective lens separation can be adjusted and calibrated in situ. Whilst several analytical models exist to predict deformation in extended or semi-infinite targets, the non-trivial nature of the wave interactions complicates the generation and development of analytical models for targets of finite depth. By interrogating specimens experimentally to acquire three-dimensional strain data points, both analytical andmore » numerical model predictions can be verified more rigorously. The technique is applied to the quasi-static deformation of a rubber sheet and dynamically to Mild Steel sheets of various thicknesses.« less

Improvement in pinch function after surgical treatment for thumb in the plane of the hand.

PubMed

Iba, K; Wada, T; Aoki, M; Yamashita, T

2012-02-01

Thumb in the plane of the hand (TPH) is a congenital deformity in which the nail plane of the radial-most digit is parallel to that of other digits, but structurally the digit retains the characteristics of a thumb. Four hands from four patients were retrospectively diagnosed as having TPH, with the underlying congenital conditions being symbrachydactyly, cleft hand and constriction band syndrome. Thumb web-plasty was carried out in all hands; one required additional rotation osteotomy of the metacarpal. Postoperative hand function was markedly improved and pinch function was possible in all cases. In most cases of TPH, the thumb has the potential to act in opposition, indicating that a thumb web-plasty is worth considering as an initial procedure.

Tidal deformations of compact stars with crystalline quark matter

NASA Astrophysics Data System (ADS)

Lau, S. Y.; Leung, P. T.; Lin, L.-M.

2017-05-01

We study the tidal deformability of bare quark stars and hybrid compact stars composed of a quark-matter core in general relativity, assuming that the deconfined quark matter exists in a crystalline color superconducting phase. We find that taking the elastic property of crystalline quark matter into account in the calculation of the tidal deformability can break the universal I-Love relation discovered for fluid compact stars, which connects the moment of inertia and tidal deformability. Our result suggests that measurements of the moment of inertia and tidal deformability can in principle be used to test the existence of solid quark stars, despite our ignorance of the high-density equation of state. Assuming that the moment of inertia can be measured to 10% level, one can then distinguish a 1.4 (1 ) M⊙ solid quark star described by our quark-matter equation of state model with a gap parameter Δ =25 MeV from a fluid compact star if the tidal deformability can be measured to about 10% (45%) level. On the other hand, we find that the nuclear matter fluid envelope of a hybrid star can screen out the effect of the solid core significantly so that the resulting I-Love relation for hybrid stars still agrees with the universal relation for fluid stars to about 1% level.

Numerical investigations on aerodynamic forces of deformable foils in hovering motions

NASA Astrophysics Data System (ADS)

Su, Xiaohui; Yin, Zhen; Cao, Yuanwei; Zhao, Yong

2017-04-01

In this paper, the aerodynamic forces of deformable foils for hovering flight are numerically investigated by a two-dimensional finite-volume arbitrary Lagrangian Eulerian Navier-Stokes solver. The effects of deformation on the lift force generation mechanisms of deformable wings in hovering flight are studied by comparison and analysis of deformable and rigid wing results. The prescribed deformation of the wings changes their morphing during hovering motion in both camber and angle of incidence. The effects of deflection amplitude, deflection phase, and rotation location on the aerodynamic performances of the foils, as well as the associated flow structures, are investigated in details, respectively. Results obtained show that foil morphing changes both Leading Edge Vortex (LEV) and Trailing Edge Vortex (TEV) generation and development processes. Consequently, the lift force generation mechanisms of deformable wings differ from those of rigid foil models. For the full deformation foil model studied, the effect of foil deformation enhances its lift force during both wake capture and delayed stall. There is an optimized camber amplitude, which was found to be 0.1*chord among those cases simulated. Partial deformation in the foil does not enhance its lift force due to unfavorable foil camber. TEV is significantly changed by the local angle of attack due to the foil deformation. On the other hand, Trailing Edge Flap (TEF) deflection in the hinge connected two-rigid-plate model directly affects the strength of both the LEV and TEV, thus influencing the entire vortex shedding process. It was found that lift enhancement can reach up to 33.5% just by the TEF deflection alone.

Breath alcohol of anesthesiologists using alcohol hand gel and the "five moments for hand hygiene" in routine practice.

PubMed

Lindsay, Helen A; Hannam, Jacqueline A; Bradfield, Charles N; Mitchell, Simon J

2016-08-01

Appropriate hand hygiene reduces hospital-acquired infections. Anesthesiologists work in environments with numerous hand hygiene opportunities (HHOs). In a prospective observational study, we investigated the potential for an anesthesiologist to return a positive alcohol breath test during routine practice when using alcohol hand gel. We observed ten volunteer anesthesiologists over four hours while they implemented the World Health Organization (WHO) "five moments for hand hygiene" using our hospital's adopted standard 70% ethanol hand gel. We measured the expired alcohol concentration at shift start and every fifteen minutes thereafter with a fuel cell breathalyzer calibrated to measure the percentage of blood alcohol concentration (BAC). Blood alcohol specimens (analyzed with gas chromatography) were collected at shift start and, when possible, immediately after a participant's first positive breathalyzer test. Of the 130 breathalyzer tests obtained, there were eight (6.2%) positive breath alcohol results from six of the ten participants, all within two minutes of a HHO. The highest value breathalyzer BAC recorded was 0.064%, with an overall mean (SD) of 0.023 (0.017)%. Five (62.5%) of the positive breathalyzer tests returned to zero in less than seven minutes. All of three blood specimens obtained immediately after a positive breathalyzer reading tested negative for alcohol. Anesthesia practitioners using alcohol hand gel in a manner that conforms with recommended hand hygiene can test positive for alcohol on a breathalyzer assay. Positive tests probably arose from inhalation of alcohol vapour into the respiratory dead space following gel application. If workplace breath testing for alcohol is implemented, it should be completed more than 15 min after applying alcohol hand gel. Positive results should be verified with a BAC test.

Rheumatoid hand surgery: differing perceptions amongst surgeons, rheumatologists and therapists in the UK.

PubMed

Burke, F D; Miranda, S M; Owen, V M F; Bradley, M J; Sinha, S

2011-10-01

Rheumatoid arthritis is a systemic disease that requires coordinated management by rheumatologists, surgical specialists and therapists working in a multidisciplinary team. Differences of opinion within the team may adversely affect patient care. Our aim was to assess differences in perception about rheumatoid hand surgery between rheumatologists, hand surgeons and hand therapists in the UK. We used a postal questionnaire to assess commonly performed rheumatoid hand operations. For each procedure, respondents rated the most important indication for surgery and scored effectiveness at reducing pain, improving function and aesthetics, and preventing deformity. Statistically significant differences were found between all three groups with regards to expected outcome and main indications for surgery. We concluded that significant differences do exist in the perceptions of rheumatologists, surgeons and therapists. Rheumatoid hand operations require more detailed study, clarifying indications and outcome to allow consistent advice to patients from all members of the multidisciplinary team.

Dealing with systematic laser scanner errors due to misalignment at area-based deformation analyses

NASA Astrophysics Data System (ADS)

Holst, Christoph; Medić, Tomislav; Kuhlmann, Heiner

2018-04-01

The ability to acquire rapid, dense and high quality 3D data has made terrestrial laser scanners (TLS) a desirable instrument for tasks demanding a high geometrical accuracy, such as geodetic deformation analyses. However, TLS measurements are influenced by systematic errors due to internal misalignments of the instrument. The resulting errors in the point cloud might exceed the magnitude of random errors. Hence, it is important to assure that the deformation analysis is not biased by these influences. In this study, we propose and evaluate several strategies for reducing the effect of TLS misalignments on deformation analyses. The strategies are based on the bundled in-situ self-calibration and on the exploitation of two-face measurements. The strategies are verified analyzing the deformation of the Onsala Space Observatory's radio telescope's main reflector. It is demonstrated that either two-face measurements as well as the in-situ calibration of the laser scanner in a bundle adjustment improve the results of deformation analysis. The best solution is gained by a combination of both strategies.

Simulation of Texture Evolution during Uniaxial Deformation of Commercially Pure Titanium

NASA Astrophysics Data System (ADS)

Bishoyi, B.; Debta, M. K.; Yadav, S. K.; Sabat, R. K.; Sahoo, S. K.

2018-03-01

The evolution of texture in commercially pure (CP) titanium during uniaxial tension and compression through VPSC (Visco-plastic self-consistent) simulation is reported in the present study. CP-titanium was subjected to both uniaxial tension and compression upto 35% deformation. During uniaxial tension, tensile twin of \\{10\\bar{1}2\\}\\unicode{x003C;}\\bar{1}011\\unicode{x003E;} type and compressive twin of \\{11\\bar{2}2\\}\\unicode{x003C;}11\\bar{2}\\bar{3}\\unicode{x003E;} type were observed in the samples. However, only tensile twin of \\{10\\bar{1}2\\}\\unicode{x003C;}\\bar{1}011\\unicode{x003E;} type and compressive twin of type was observed in the samples during uniaxial compression. Volume fractions of the twins were increased linearly as a function of percentage deformation during uniaxial tension. Whereas, during uniaxial compression the twinning volume fraction was increased up to 20% deformation and then decreased rapidly on further increasing the percentage deformation. During uniaxial tension, the general t-type textures were observed in the samples irrespective of the percentage deformation. The initial non-basal texture was oriented to split basal texture during uniaxial compression of the sample. VPSC formulation was used for simulating the texture development in the material. Different hardening parameters were estimated through correlating the simulated stress-strain curve with the experimental stress-strain data. It was observed that, prismatic slip \\{10\\bar{1}0\\}\\unicode{x003C;}11\\bar{2}0\\unicode{x003E;} operated as the primary deformation mode during uniaxial tension whereas basal slip \\{0001\\}\\unicode{x003C;}11\\bar{2}0\\unicode{x003E;} acquired the leading role during deformation through uniaxial compression. It was also revealed that active deformation modes were fully depending on percentage deformation, loading direction, and orientation of grains.

Mars Hand Lens Imager Sends Ultra High-Res Photo from Mars

NASA Image and Video Library

2013-10-17

This image of a U.S. penny on a calibration target was taken by the Mars Hand Lens Imager MAHLI aboard NASA Curiosity rover in Gale Crater on Mars. At 14 micrometers per pixel, this is the highest-resolution image that MAHLI can acquire.

Combining variational and model-based techniques to register PET and MR images in hand osteoarthritis

NASA Astrophysics Data System (ADS)

Magee, Derek; Tanner, Steven F.; Waller, Michael; Tan, Ai Lyn; McGonagle, Dennis; Jeavons, Alan P.

2010-08-01

Co-registration of clinical images acquired using different imaging modalities and equipment is finding increasing use in patient studies. Here we present a method for registering high-resolution positron emission tomography (PET) data of the hand acquired using high-density avalanche chambers with magnetic resonance (MR) images of the finger obtained using a 'microscopy coil'. This allows the identification of the anatomical location of the PET radiotracer and thereby locates areas of active bone metabolism/'turnover'. Image fusion involving data acquired from the hand is demanding because rigid-body transformations cannot be employed to accurately register the images. The non-rigid registration technique that has been implemented in this study uses a variational approach to maximize the mutual information between images acquired using these different imaging modalities. A piecewise model of the fingers is employed to ensure that the methodology is robust and that it generates an accurate registration. Evaluation of the accuracy of the technique is tested using both synthetic data and PET and MR images acquired from patients with osteoarthritis. The method outperforms some established non-rigid registration techniques and results in a mean registration error that is less than approximately 1.5 mm in the vicinity of the finger joints.

Chondro-manubrial deformity and bifid rib, rare variations seen in pectus carinatum: a radiological finding.

PubMed

Allwyn Joshua, S; Shetty, Lathika; Pare, V S; Sebastian, Roopa

2013-07-01

Pectus carinatum or protrusion deformity of chest wall is less frequently occurring anterior chest wall deformity when compared to pectus excavatum. It may be classified as type 1 or chondro-gladiolar and type 2 or chondro-manubrial deformity. Other variations seen are symmetrical and asymmetrical pectus carinatum. Here we present two unique case reports, one with chondro-manubrial deformity (Currarino-Silverman syndrome) and other with asymmetrical pectus carinatum having bifid rib which are some of the rare variations seen in pectus carinatum found during Computerized tomographic examination. Currarino-Silverman syndrome is a type 2 pectus carinatum, a rare deformity with chondro-manubrial involvement and usually associated congenital heart diseases. Early fusion of sternal plates is one of the known theories in producing this deformity. On the other hand, asymmetrical pectus deformity are usually seen due to imbalance or abnormality in growth plates of costal cartilages leading to forked rib or bifid rib, which are accidently seen on radiological examination. To conclude, our reports would help in differential diagnosis from frequently occurring conditions affecting chest like chondro-gladiolar deformity, pectus excavatum, chest wall tumours, rib fractures and intra thoracic ribs.

Estimation of Surface Deformation due to Pasni Earthquake Using SAR Interferometry

NASA Astrophysics Data System (ADS)

Ali, M.; Shahzad, M. I.; Nazeer, M.; Kazmi, J. H.

2018-04-01

Earthquake cause ground deformation in sedimented surface areas like Pasni and that is a hazard. Such earthquake induced ground displacements can seriously damage building structures. On 7 February 2017, an earthquake with 6.3 magnitudes strike near to Pasni. We have successfully distinguished widely spread ground displacements for the Pasni earthquake by using InSAR-based analysis with Sentinel-1 satellite C-band data. The maps of surface displacement field resulting from the earthquake are generated. Sentinel-1 Wide Swath data acquired from 9 December 2016 to 28 February 2017 was used to generate displacement map. The interferogram revealed the area of deformation. The comparison map of interferometric vertical displacement in different time period was treated as an evidence of deformation caused by earthquake. Profile graphs of interferogram were created to estimate the vertical displacement range and trend. Pasni lies in strong earthquake magnitude effected area. The major surface deformation areas are divided into different zones based on significance of deformation. The average displacement in Pasni is estimated about 250 mm. Maximum pasni area is uplifted by earthquake and maximum uplifting occurs was about 1200 mm. Some of areas was subsidized like the areas near to shoreline and maximum subsidence was estimated about 1500 mm. Pasni is facing many problems due to increasing sea water intrusion under prevailing climatic change where land deformation due to a strong earthquake can augment its vulnerability.

Three different methods for treating multiple enchondromatosis in one hand.

PubMed

Lu, Hui; Chen, Qiang; Shen, Hui; Shen, Xiang-Qian; Wu, Shou-Cheng; Lin, Xiang-Jin

2015-01-01

Ollier's disease remains comparatively rare, and is a non-hereditary cartilage dysplasia of bone. It is usually associated with problems such as deformity and fracture. Three different methods were used in a one-hand of 15-year-old boy reporting his pain in the left hand and swellings. After the curettage of tumor, regarding as the differences of all parts of the bone structure reconstruction in the patient's hand, we chose three following methods for this boy, i.e. fixed by the locking plate with calcium phosphate cement, filled with allograft bone, curetted the tumor without any bone graft. After the surgery, the patient was able to perform full motion of the operated hand. No evidence of recurrence was noted four years after surgery. To choose the different ways with bone grafts or not that relies on the patients' conditions for bone structure reconstruction. However, patients with large osseous defects or pathological fracture, we demand full bone graft and reliable internal fixation. After surgery, early exercises can reach a desirable result and functional recovery.

Kirschner-wire fixation for postburn flexion contracture deformity and consequences on articular surface.

PubMed

Sungur, Nezih; Ulusoy, Mustafa Gürhan; Boyacgil, Süreyya; Ortaparmak, Hülya; Akyüz, Mihriban; Ortak, Turgut; Koçer, Uğur; Sensöz, Omer

2006-02-01

Kirschner-wire (K-wire) fixation for 3-6 weeks is an approved method for stabilization of the fingers after the release of flexion contracture deformity. On the other hand, articular surface damage in small joints due to pin fixation is still a topic of debate. Reports claiming permanent joint destruction due to this procedure exist in the literature. To clarify this doubt, a prospective study was carried out in 72 patients with flexion contracture of the hand fingers. After the surgical release of the deformity, immobilization of the interphalangeal (IP) and metacarpophalangeal (MCP) joints was carried out with K-wire fixation for 3 weeks. Clinical evaluation of the patients was accomplished with total active motion (TAM), grip, and pinch force measurements, whereas magnetic resonance (MR) and radionuclide imaging were used as radiodiagnostic tools. Mean follow-up period of the patients was 32 months. Satisfactory results were obtained in terms of functional and esthetic aspects. Evaluation of the data derived from the clinical and radiologic measurements revealed no permanent articular surface damage. K-wire fixation was documented to be an invaluable therapeutic approach not only to prevent recurrence of the contracture deformity but also to stabilize the skin graft effectively. This technique was concluded to provide effective immobilization without permanent articular damage.

The behaviour of resonances in Hecke triangular billiards under deformation

NASA Astrophysics Data System (ADS)

Howard, P. J.; O'Mahony, P. F.

2007-08-01

The right-hand boundary of Artin's billiard on the Poincaré half-plane is continuously deformed to generate a class of chaotic billiards which includes fundamental domains of the Hecke groups Γ(2, n) at certain values of the deformation parameter. The quantum scattering problem in these open chaotic billiards is described and the distributions of both real and imaginary parts of the resonant eigenvalues are investigated. The transitions to arithmetic chaos in the cases n ∈ {4, 6} are closely examined and the explicit analytic form for the scattering matrix is given together with the Fourier coefficients for the scattered wavefunction. The n = 4 and 6 cases have an additional set of regular equally spaced resonances compared to Artin's billiard (n = 3). For a general deformation, a numerical procedure is presented which generates the resonance eigenvalues and the evolution of the eigenvalues is followed as the boundary is varied continuously which leads to dramatic changes in their distribution. For deformations away from the non-generic arithmetic cases, including that of the tiling Hecke triangular billiard n = 5, the distributions of the positions and widths of the resonances are consistent with the predictions of a random matrix theory.

Three saints with deformed extremities in an Italian Renaissance altarpiece.

PubMed

Albury, W R; Weisz, G M

2017-03-01

A fifteenth-century Florentine altarpiece painted by the Pollaiuolo brothers, Antonio (1433-1498) and Piero (1443-1496), shows three saints with evident deformities of the hands and feet. The pathologies concerned are tentatively identified, and various rationales for their presence in the painting are discussed. Of particular importance is the location of the altarpiece in a chapel which houses the tomb of the Cardinal of Portugal, Prince James of Lusitania (1433-1459). It is argued that both the artistic style of the day and the religious symbolism of the Cardinal's funeral chapel contributed to the artists' decision to portray the saints with deformities. An unnatural curvature of the fifth finger was apparently considered elegant in fifteenth-century paintings, and the depiction of bare feet with hallux valgus gave them a shape which approximated and could have been caused by fashionable pointed shoes. But in addition, deformities in religious art could be symbolic of suffering and martyrdom, a theme which the Cardinal's chapel emphasised in a number of ways. It is suggested therefore that the Pollaiuolo altarpiece reconciles these two disparate factors, portraying genuine deformities in a way that was artistically stylish and symbolically meaningful.

Toward mapping surface deformation in three dimensions using InSAR

USGS Publications Warehouse

Wright, Tim J.; Parsons, Barry E.; Lu, Zhong

2004-01-01

One of the limitations of deformation measurements made with interferometric synthetic aperture radar (InSAR) is that an interferogram only measures one component of the surface deformation — in the satellite's line of sight. We investigate strategies for mapping surface deformation in three dimensions by using multiple interferograms, with different imaging geometries. Geometries for both current and future missions are evaluated, and their abilities to resolve the displacement vector are compared. The north component is always the most difficult to determine using data from near-polar orbiting satellites. However, a satellite with an inclination of about 60°/120° would enable all three components to be well resolved. We attempt to resolve the 3D displacements for the 23 October 2002 Nenana Mountain (Alaska) Earthquake. The north component's error is much larger than the signal, but proxies for eastward and vertical motion can be determined if the north component is assumed negligible. Inversions of hypothetical coseismic interferograms demonstrate that earthquake model parameters can be well recovered from two interferograms, acquired on ascending and descending tracks.

In-vivo spinal cord deformation in flexion

NASA Astrophysics Data System (ADS)

Yuan, Qing; Dougherty, Lawrence; Margulies, Susan S.

1997-05-01

Traumatic mechanical loading of the head-neck complex results cervical spinal cord injury when the distortion of the cord is sufficient to produce functional or structural failure of the cord's neural and/or vascular components. Characterizing cervical spinal cord deformation during physiological loading conditions is an important step to defining a comprehensive injury threshold associated with acute spinal cord injury. In this study, in vivo quasi- static deformation of the cervical spinal cord during flexion of the neck in human volunteers was measured using magnetic resonance (MR) imaging of motion with spatial modulation of magnetization (SPAMM). A custom-designed device was built to guide the motion of the neck and enhance more reproducibility. the SPAMM pulse sequence labeled the tissue with a series of parallel tagging lines. A single- shot gradient-recalled-echo sequence was used to acquire the mid-sagittal image of the cervical spine. A comparison of the tagged line pattern in each MR reference and deformed image pair revealed the distortion of the spinal cord. The results showed the cervical spinal cord elongates during head flexion. The elongation experienced by the spinal cord varies linearly with head flexion, with the posterior surface of the cord stretching more than the anterior surface. The maximal elongation of the cord is about 12 percent of its original length.

Interventions to improve patient hand hygiene: a systematic review.

PubMed

Srigley, J A; Furness, C D; Gardam, M

2016-09-01

Nosocomial pathogens may be acquired by patients via their own unclean hands, but there has been relatively little emphasis on patient hand hygiene as a tool for preventing healthcare-associated infections (HCAIs). The aim of this systematic review was to determine the efficacy of patient hand hygiene interventions in reducing HCAIs and improving patient hand hygiene rates compared to usual care. Electronic databases and grey literature were searched to August 2014. Experimental and quasi-experimental studies were included if they evaluated a patient hand hygiene intervention conducted in an acute or chronic healthcare facility and included HCAI incidence and/or patient hand hygiene rates as an outcome. All steps were performed independently by two investigators. Ten studies were included, most of which were uncontrolled before-after studies (N=8). The majority of interventions (N=7) were multi-modal, with components similar to healthcare worker hand hygiene programmes, including education, reminders, audit and feedback, and provision of hand hygiene products. Six studies reported HCAI outcomes and four studies assessed patient hand hygiene rates; all demonstrated improvements but were at moderate to high risk of bias. In conclusion, interventions to improve patient hand hygiene may reduce the incidence of HCAIs and improve hand hygiene rates, but the quality of evidence is low. Future studies should use stronger designs and be more selective in their choice of outcomes. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

An educational intervention to improve hand hygiene compliance in Vietnam.

PubMed

Phan, Hang Thi; Tran, Hang Thi Thuy; Tran, Hanh Thi My; Dinh, Anh Pham Phuong; Ngo, Ha Thanh; Theorell-Haglow, Jenny; Gordon, Christopher J

2018-03-07

Hand hygiene compliance is the basis of infection control programs. In developing countries models to improve hand hygiene compliance to reduce healthcare acquired infections are required. The aim of this study was to determine hand hygiene compliance following an educational program in an obstetric and gynecological hospital in Vietnam. Health care workers from neonatal intensive care, delivery suite and a surgical ward from Hung Vuong Hospital, Ho Chi Minh City, Vietnam undertook a 4-h educational program targeting hand hygiene. Compliance was monitored monthly for six months following the intervention. Hand hygiene knowledge was assessed at baseline and after six months of the study. There were 7124 opportunities over 370 hand hygiene recording sessions with 1531 opportunities at baseline and 1620 at 6 months following the intervention. Hand hygiene compliance increased significantly from baseline across all sites (43.6% [95% Confidence interval CI: 41.1-46.1] to 63% [95% CI: 60.6-65.3]; p < 0.0001). Health care worker hand hygiene compliance increased significantly after intervention (p < 0.0001). There were significant improvements in knowledge scores from baseline to 2 months post educational intervention with mean difference standard deviations (SD): 1.5 (2.5); p < 0.001). A simple educational model was implemented in a Vietnamese hospital that revealed good hand hygiene compliance for an extended period of time. Hand hygiene knowledge increased during the intervention. This hand hygiene model could be used in developing countries were resources are limited.

The evolution of human and ape hand proportions.

PubMed

Almécija, Sergio; Smaers, Jeroen B; Jungers, William L

2015-07-14

Human hands are distinguished from apes by possessing longer thumbs relative to fingers. However, this simple ape-human dichotomy fails to provide an adequate framework for testing competing hypotheses of human evolution and for reconstructing the morphology of the last common ancestor (LCA) of humans and chimpanzees. We inspect human and ape hand-length proportions using phylogenetically informed morphometric analyses and test alternative models of evolution along the anthropoid tree of life, including fossils like the plesiomorphic ape Proconsul heseloni and the hominins Ardipithecus ramidus and Australopithecus sediba. Our results reveal high levels of hand disparity among modern hominoids, which are explained by different evolutionary processes: autapomorphic evolution in hylobatids (extreme digital and thumb elongation), convergent adaptation between chimpanzees and orangutans (digital elongation) and comparatively little change in gorillas and hominins. The human (and australopith) high thumb-to-digits ratio required little change since the LCA, and was acquired convergently with other highly dexterous anthropoids.

The evolution of human and ape hand proportions

PubMed Central

Almécija, Sergio; Smaers, Jeroen B.; Jungers, William L.

2015-01-01

Human hands are distinguished from apes by possessing longer thumbs relative to fingers. However, this simple ape-human dichotomy fails to provide an adequate framework for testing competing hypotheses of human evolution and for reconstructing the morphology of the last common ancestor (LCA) of humans and chimpanzees. We inspect human and ape hand-length proportions using phylogenetically informed morphometric analyses and test alternative models of evolution along the anthropoid tree of life, including fossils like the plesiomorphic ape Proconsul heseloni and the hominins Ardipithecus ramidus and Australopithecus sediba. Our results reveal high levels of hand disparity among modern hominoids, which are explained by different evolutionary processes: autapomorphic evolution in hylobatids (extreme digital and thumb elongation), convergent adaptation between chimpanzees and orangutans (digital elongation) and comparatively little change in gorillas and hominins. The human (and australopith) high thumb-to-digits ratio required little change since the LCA, and was acquired convergently with other highly dexterous anthropoids. PMID:26171589

Treatment of plastic deformation of the forearm in young adults with double-level osteotomies: case reports.

PubMed

Moon, Edward S; Howlett, John; Wiater, Brett P; Trumble, Thomas E

2011-04-01

Plastic deformation of the forearm is a rare injury in young adults that occurs when a slow bending or rotational force is applied to the arm, most commonly in the setting of an industrial workplace accident. There are currently no guidelines for treatment of the residual forearm deformity that often results in limitations of forearm supination and pronation. We present 2 cases demonstrating that deformity correction with single cortex, double-level osteotomies combined with rigid plate fixation and early range of motion exercise that results in good functional outcomes. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Model deformation measurements at a cryogenic wind tunnel using photogrammetry

NASA Technical Reports Server (NTRS)

Burner, A. W.; Snow, W. L.; Goad, W. K.

1985-01-01

A photogrammetric closed circuit television system to measure model deformation at the National Transonic Facility (NTF) is described. The photogrammetric approach was chosen because of its inherent rapid data recording of the entire object field. Video cameras are used to acquire data instead of film cameras due to the inaccessibility of cameras which must be housed within the cryogenic, high pressure plenum of this facility. Data reduction procedures and the results of tunnel tests at the NTF are presented.

Model Deformation Measurements at a Cryogenic Wind Tunnel Using Photogrammetry

NASA Technical Reports Server (NTRS)

Burner, A. W.; Snow, W. L.; Goad, W. K.

1982-01-01

A photogrammetric closed circuit television system to measure model deformation at the National Transonic Facility (NTF) is described. The photogrammetric approach was chosen because of its inherent rapid data recording of the entire object field. Video cameras are used to acquire data instead of film cameras due to the inaccessibility of cameras which must be housed within the cryogenic, high pressure plenum of this facility. Data reduction procedures and the results of tunnel tests at the NTF are presented.

Rheology and Seismic Potential of Experimentally-Deformed Natural Serpentinites

NASA Astrophysics Data System (ADS)

Gasc, J.; Hilairet, N.; Wang, Y.; Yu, T.; Ferrand, T. P.; Schubnel, A.

2016-12-01

The origin of intermediate-depth earthquakes, which occur at depths of 60-300 km along subducting slabs, remains somehow enigmatic. In the pressure and temperature conditions involved, rocks should indeed deform in a ductile fashion. One, or more, mechanism is therefore responsible for mechanical instabilities. Dehydration embrittlement, due to serpentine breakdown, was long considered a good candidate. However, in recent years, experimental studies have challenged this theory, by showing that deformation and faulting of serpentinites, related to dehydration, occurs in a stable and aseismic way (Chernak and Hirth, 2011; Gasc et al., 2011). In order to assess the seismic potential of serpentinites, high pressure deformation experiments were carried out on natural samples, during which micro-seismicity was monitored by recording Acoustic Emissions (AE's). Deformation was performed at pressures of 3-5 GPa, using a Deformation-DIA device, and over a wide range of temperatures, both within and outside antigorite's stability field. The results show that, below 400 C, serpentinite deformation involves aseismic semi-brittle mechanisms, even in cases where strain localization is observed. At high temperature (i.e., above 600 C), despite conditions propitious to dehydration embrittlement (i.e., with fast strain rates and reaction kinetics), joint deformation and dehydration leads to ductile shear, without generation of AE's. On the other hand, a brittle temperature window, centered at ca. 500 C, is evidenced. In this latter case, AE's are consistently collected upon deformation and faulting with extremely sharp strain localization is observed. This brittle field may therefore be a source of seismicity in subducting slabs at mantle pressures. However, analysis of the acoustic signal shows that it is relatively orders of magnitude weaker than its real-earth counterparts, which suggests that other mechanisms are responsible for larger intermediate-depth earthquakes. In fact

Semmelweis revisited: hand hygiene and nosocomial disease transmission in the anesthesia workstation.

PubMed

Biddle, Chuck

2009-06-01

Hospital-acquired infections occur at an alarmingly high frequency, possibly affecting as many as 1 in 10 patients, resulting in a staggering morbidity and an annual mortality of many tens of thousands of patients. Appropriate hand hygiene is highly effective and represents the simplest approach that we have to preventing nosocomial infections. The Agency for Healthcare Research and Quality has targeted hand-washing compliance as a top research agenda item for patient safety. Recent research has identified inadequate hand washing and contaminated anesthesia workstation issues as likely contributors to nosocomial infections, finding aseptic practices highly variable among providers. It is vital that all healthcare providers, including anesthesia providers, appreciate the role of inadequate hand hygiene in nosocomial infection and meticulously follow the mandates of the American Association of Nurse Anesthetists and other professional healthcare organizations.

Image-Guided Intraoperative Cortical Deformation Recovery Using Game Theory: Application to Neocortical Epilepsy Surgery

PubMed Central

DeLorenzo, Christine; Papademetris, Xenophon; Staib, Lawrence H.; Vives, Kenneth P.; Spencer, Dennis D.; Duncan, James S.

2010-01-01

During neurosurgery, nonrigid brain deformation prevents preoperatively-acquired images from accurately depicting the intraoperative brain. Stereo vision systems can be used to track intraoperative cortical surface deformation and update preoperative brain images in conjunction with a biomechanical model. However, these stereo systems are often plagued with calibration error, which can corrupt the deformation estimation. In order to decouple the effects of camera calibration from the surface deformation estimation, a framework that can solve for disparate and often competing variables is needed. Game theory, which was developed to handle decision making in this type of competitive environment, has been applied to various fields from economics to biology. In this paper, game theory is applied to cortical surface tracking during neocortical epilepsy surgery and used to infer information about the physical processes of brain surface deformation and image acquisition. The method is successfully applied to eight in vivo cases, resulting in an 81% decrease in mean surface displacement error. This includes a case in which some of the initial camera calibration parameters had errors of 70%. Additionally, the advantages of using a game theoretic approach in neocortical epilepsy surgery are clearly demonstrated in its robustness to initial conditions. PMID:20129844

Deformation of island-arc lithosphere due to steady plate subduction

NASA Astrophysics Data System (ADS)

Fukahata, Yukitoshi; Matsu'ura, Mitsuhiro

2016-02-01

Steady plate subduction elastically brings about permanent lithospheric deformation in island arcs, though this effect has been neglected in most studies based on elastic dislocation theory. We investigate the characteristics of the permanent lithospheric deformation using a kinematic model, in which steady slip motion is given along a plate interface in the elastic lithosphere overlying the viscoelastic asthenosphere under gravity. As a rule of thumb, long-term lithospheric deformation can be understood as a bending of an elastic plate floating on non-viscous fluid, because the asthenosphere behaves like water on the long term. The steady slip below the lithosphere-asthenosphere boundary does not contribute to long-term lithospheric deformation. Hence, the key parameters that control the lithospheric deformation are only the thickness of the lithosphere and the geometry of the plate interface. Slip on a plate interface generally causes substantial vertical displacement, and gravity always tries to retrieve the original gravitational equilibrium. For a curved plate interface gravity causes convex upward bending of the island-arc lithosphere, while for a planar plate interface gravity causes convex downward bending. Larger curvature and thicker lithosphere generally results in larger deformation. When the curvature changes along the plate interface, internal deformation is also involved intrinsically, which modifies the deformation field due to gravity. Because the plate interface generally has some curvature, at least near the trench, convex upward bending of the island-arc lithosphere, which involves uplift of island-arc and subsidence around the trench, is always realized. On the other hand, the deformation field of the island-arc lithosphere sensitively depends on lithospheric thickness and plate interface geometry. These characteristics obtained by the numerical simulation are consistent with observed topography and free-air gravity anomalies in subduction

3-Dimensional Microstructure of Al-Al3Ti Alloy Severely Deformed by ECAP

NASA Astrophysics Data System (ADS)

Sato, Hisashi; Hishikawa, Takahisa; Makino, Yuuki; Kunimine, Takahiro; Watanabe, Yoshimi

Microstructure of Al-Al3Ti alloy deformed by Equal-Channel-Angular Pressing (ECAP) is 3-dimensionally investigated. Especially, distribution of Al3Ti particles is focused in this study. The Al-Al3Ti alloy has coarse Al3Ti platelet particles in α-Al matrix. When the Al-Al3Ti alloy is deformed by ECAP under route A, fine Al3Ti platelet particles are observed. These Al3Ti platelet particles are aligned along to deformation axis, and its plane normal is perpendicular to the deformation axis. On the other hand, Al-Al3Ti alloy ECAPed under route Bc forms several groups consisted of fine Al3Ti platelet particles. Moreover, longitudinal size of the Al3Ti particle groups is close to that of initial Al3Ti particles with 4-pass ECAP specimen. These distribution behaviors of the Al3Ti particle can be explained by plastic flow of α-Al matrix. Finally, it is concluded that distribution of Al3Ti particle in Al-Al3Ti alloy by ECAP is controlled by plastic deformation of α-Al matrix.

Custom-made silicone hand prosthesis: A case study.

PubMed

Nayak, S; Lenka, P K; Equebal, A; Biswas, A

2016-09-01

Up to now, a cosmetic glove was the most common method for managing transmetacarpal (TMC) and carpometacarpal (CMC) amputations, but it is devoid of markings and body color. At this amputation level, it is very difficult to fit a functional prosthesis because of the short available length, unsightly shape, grafted skin, contracture and lack of functional prosthetic options. A 30-year-old male came to our clinic with amputation at the 1st to 4th carpometacarpal level and a 5th metacarpal that was projected laterally and fused with the carpal bone. The stump had grafted skin, redness, and an unhealed suture line. He complained of pain projected over the metacarpal and suture area. The clinical team members decided to fabricate a custom-made silicone hand prosthesis to accommodate the stump, protect the grafted skin, improve the hand's appearance and provide some passive function. The custom silicone hand prosthesis was fabricated with modified flexible wires to provide passive interphalangeal movement. Basic training, care and maintenance instructions for the prosthesis were given to the patient. The silicone hand prosthesis was able to restore the appearance of the lost digits and provide some passive function. His pain (VAS score) was reduced. Improvement in activities of daily living was found in the DASH questionnaire and Jebsen-Taylor Hand Function test. A silicone glove is a good option for more distal amputations, as it can accommodate any deformity, protect the skin, enhance the appearance and provide functional assistance. This case study provides a simple method to get passively movable fingers after proximal hand amputation. Copyright © 2016. Published by Elsevier Masson SAS.

Primal-mixed formulations for reaction-diffusion systems on deforming domains

NASA Astrophysics Data System (ADS)

Ruiz-Baier, Ricardo

2015-10-01

We propose a finite element formulation for a coupled elasticity-reaction-diffusion system written in a fully Lagrangian form and governing the spatio-temporal interaction of species inside an elastic, or hyper-elastic body. A primal weak formulation is the baseline model for the reaction-diffusion system written in the deformed domain, and a finite element method with piecewise linear approximations is employed for its spatial discretization. On the other hand, the strain is introduced as mixed variable in the equations of elastodynamics, which in turn acts as coupling field needed to update the diffusion tensor of the modified reaction-diffusion system written in a deformed domain. The discrete mechanical problem yields a mixed finite element scheme based on row-wise Raviart-Thomas elements for stresses, Brezzi-Douglas-Marini elements for displacements, and piecewise constant pressure approximations. The application of the present framework in the study of several coupled biological systems on deforming geometries in two and three spatial dimensions is discussed, and some illustrative examples are provided and extensively analyzed.

A Novel Method for Quantifying Human In Situ Whole Brain Deformation under Rotational Loading Using Sonomicrometry.

PubMed

Alshareef, Ahmed; Giudice, J Sebastian; Forman, Jason; Salzar, Robert S; Panzer, Matthew B

2018-03-01

Traumatic brain injuries (TBI) are one of the least understood injuries to the body. Finite element (FE) models of the brain have been crucial for understanding concussion and for developing injury mitigation systems; however, the experimental brain deformation data currently used to validate these models are limited. The objective of this study was to develop a methodology for the investigation of in situ three-dimensional brain deformation during pure rotational loading of the head, using sonomicrometry. Sonomicrometry uses ultrasonic pulses to measure the dynamic distances between piezoelectric crystals implanted in any sound-transmitting media. A human cadaveric head-neck specimen was acquired 14 h postmortem and was instrumented with an array of 32 small sonomicrometry crystals embedded in the head: 24 crystals were implanted in the brain, and 8 were fixed to the inner skull. A dynamic rotation was then applied to the head using a closed-loop controlled test device. Four pulses with different severity levels were applied around three orthogonal anatomical axes of rotation. A repeated test of the highest severity rotation was conducted in each axis to assess repeatability. All tests were completed within 56 h postmortem. Overall, the combined experimental and sonomicrometry methods were demonstrated to reliably and repeatedly capture three-dimensional dynamic deformation of an intact human brain. These methods provide a framework for using sonomicrometry to acquire multidimensional experimental data required for FE model development and validation, and will lend insight into the deformations sustained by the brain during impact.

Comparison of molecular dynamics and superfamily spaces of protein domain deformation.

PubMed

Velázquez-Muriel, Javier A; Rueda, Manuel; Cuesta, Isabel; Pascual-Montano, Alberto; Orozco, Modesto; Carazo, José-María

2009-02-17

It is well known the strong relationship between protein structure and flexibility, on one hand, and biological protein function, on the other hand. Technically, protein flexibility exploration is an essential task in many applications, such as protein structure prediction and modeling. In this contribution we have compared two different approaches to explore the flexibility space of protein domains: i) molecular dynamics (MD-space), and ii) the study of the structural changes within superfamily (SF-space). Our analysis indicates that the MD-space and the SF-space display a significant overlap, but are still different enough to be considered as complementary. The SF-space space is wider but less complex than the MD-space, irrespective of the number of members in the superfamily. Also, the SF-space does not sample all possibilities offered by the MD-space, but often introduces very large changes along just a few deformation modes, whose number tend to a plateau as the number of related folds in the superfamily increases. Theoretically, we obtained two conclusions. First, that function restricts the access to some flexibility patterns to evolution, as we observe that when a superfamily member changes to become another, the path does not completely overlap with the physical deformability. Second, that conformational changes from variation in a superfamily are larger and much simpler than those allowed by physical deformability. Methodologically, the conclusion is that both spaces studied are complementary, and have different size and complexity. We expect this fact to have application in fields as 3D-EM/X-ray hybrid models or ab initio protein folding.

Monitoring of landslide deformation based on the coherent targets of high resolution InSAR data

NASA Astrophysics Data System (ADS)

Fan, Jinghui; Xia, Ye; Zhao, Hongli; Li, Man; Wang, Yi; Guo, Xiaofang; Tu, Pengfei; Liu, Guang; Lin, Hao

2014-05-01

Landslides are a kind of typical natural disaster in China, which pose serious threats to civil lives, property and living environment. Therefore, the identification, monitoring and prevention of landslides have been considered as a long-term geological work for the public welfare. In this article, 8 TerraSAR-X high resolution strip-map mode images, acquired in the period from January to March 2012 and covering Fanjinping landslide in Zigui county, Hubei province, were used to test the usability in monitoring the deformation of single landslide. The results of two-pass DInSAR sketched the region and the shape of the deformation field of Fanjiaping landslide. Corner reflectors' linear deformation rate using CRInSAR method could be approximately validated by the in-situ GPS measurements. From the coherent pixels' linear deformation rate map, it was inferred that the deformation could be more obvious in the tail of the Muyubao landslide while the lowest frontier of this landslide might prevent the slide. Due to its shorter revisiting period and high bandwidth,,the high resolution TerraSAR-X images can keep better coherence than previous satellite SAR data in the test area and provide basic guarantee to monitor the deformation of single landslides.

The contribution of medializing calcaneal osteotomy on hindfoot alignment in the reconstruction of the stage II adult acquired flatfoot deformity.

PubMed

Chan, Jeremy Y; Williams, Benjamin R; Nair, Pallavi; Young, Elizabeth; Sofka, Carolyn; Deland, Jonathan T; Ellis, Scott J

2013-02-01

Successful correction of hindfoot alignment in adult acquired flatfoot deformity (AAFD) is likely influenced by the degree of medializing calcaneal osteotomy (MCO) performed, but it is not known if other reconstruction procedures significantly contribute as well. The purpose of this study was to evaluate the correlation between common preoperative and postoperative variables and hindfoot alignment. Thirty patients with stage II AAFD undergoing flatfoot reconstruction were followed prospectively. Preoperative and postoperative radiographs were reviewed to assess for correction in hindfoot alignment as measured by the change in hindfoot moment arm. Nineteen variables were analyzed, including age, gender, height, weight, body mass index (BMI), medial cuneiform-fifth metatarsal height, anteroposterior (AP) talonavicular coverage, AP talus-first metatarsal, lateral talus-first metatarsal and calcaneal pitch angles as well as intraoperative use of the MCO, lateral column lengthening (LCL), Cotton osteotomy, first tarsometatarsal fusion, flexor digitorum longus transfer, spring ligament reconstruction, and gastrocnemius recession or Achilles lengthening. Mean age was 57.3 years (range, 22-77). Final radiographs were obtained at a mean of 47 weeks (range, 25-78) postoperatively. Seven variables were found to significantly affect hindfoot moment arm. These were gender (P < .05), the amount of MCO performed (P < .001), LCL (P < .01), first tarsometatarsal fusion (P < .01), spring ligament reconstruction (P < .01), medial cuneiform-fifth metatarsal height (P < .001), and calcaneal pitch angle (P < .05). Multivariate regression analysis revealed that MCO was the only significant predictor of hindfoot moment arm. The final regression model for MCO showed a good fit (R(2) = .93, P < .001). Correction of hindfoot valgus alignment obtained in flatfoot reconstruction is primarily determined by the MCO procedure and can be modeled linearly. We believe that the hindfoot alignment

Habit tic nail deformity - a rare presentation in an 8 year old boy.

PubMed

El-Heis, S; Abadie, Al

2016-11-15

Habit tic nail deformity is a nail dystrophy resulting from habitual, repetitive trauma to the nail. It is usually acquired in adulthood, however, we report a case of habit tic nail deformity in an 8 year old boy. The diagnosis was made clinically with further history revealing that the boy repeatedly rubbed his thumbnails and pushed the cuticles. Emollient cream (Balneum®) was recommended twice daily and both the patient and his mother were educated on the behavioral nature of this condition. There was marked improvement at 6 months of treatment and further improvement at 12 months.We note that habit tic nail deformity is not exclusive to adults. Diagnosis can be made clinically. History and physical examination provide valuable clues and psychosocial links must be explored and addressed. Management is challenging and compliance with treatment is variable. Patient education, barrier methods, and behavioral therapy can be helpful in preventing further trauma to the nails.

The art and science of photography in hand surgery.

PubMed

Wang, Keming; Kowalski, Evan J; Chung, Kevin C

2014-03-01

High-quality medical photography plays an important role in teaching and demonstrating the functional capacity of the hands as well as in medicolegal documentation. Obtaining standardized, high-quality photographs is now an essential component of many surgery practices. The importance of standardized photography in facial and cosmetic surgery has been well documented in previous studies, but no studies have thoroughly addressed the details of photography for hand surgery. In this paper, we provide a set of guidelines and basic camera concepts for different scenarios to help hand surgeons obtain appropriate and informative high-quality photographs. A camera used for medical photography should come equipped with a large sensor size and an optical zoom lens with a focal length ranging anywhere from 14 to 75 mm. In a clinic or office setting, we recommend 6 standardized views of the hand and 4 views for the wrist; additional views should be taken for tendon ruptures, nerve injuries, or other deformities of the hand. For intraoperative pictures, the camera operator should understand the procedure and pertinent anatomy in order to properly obtain high-quality photographs. When digital radiographs are not available and radiographic film must be photographed, it is recommended to reduce the exposure and change the color mode to black and white to obtain the best possible pictures. The goal of medical photography is to present the subject in an accurate and precise fashion. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Model Deformation Measurements at NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Burner, A. W.

1998-01-01

Only recently have large amounts of model deformation data been acquired in NASA wind tunnels. This acquisition of model deformation data was made possible by the development of an automated video photogrammetric system to measure the changes in wing twist and bending under aerodynamic load. The measurement technique is based upon a single view photogrammetric determination of two dimensional coordinates of wing targets with a fixed third dimensional coordinate, namely the spanwise location. A major consideration in the development of the measurement system was that use of the technique must not appreciably reduce wind tunnel productivity. The measurement technique has been used successfully for a number of tests at four large production wind tunnels at NASA and a dedicated system is nearing completion for a fifth facility. These facilities are the National Transonic Facility, the Transonic Dynamics Tunnel, and the Unitary Plan Wind Tunnel at NASA Langley, and the 12-FT Pressure Tunnel at NASA Ames. A dedicated system for the Langley 16-Foot Transonic Tunnel is scheduled to be used for the first time for a test in September. The advantages, limitations, and strategy of the technique as currently used in NASA wind tunnels are presented. Model deformation data are presented which illustrate the value of these measurements. Plans for further enhancements to the technique are presented.

An instrumented object for hand exercise and assessment using a pneumatic pressure sensor

NASA Astrophysics Data System (ADS)

Mohan, A.; Tharion, G.; Kumar, R. K.; Devasahayam, S. R.

2018-05-01

Measurement of grip force is important for both exercise training and assessment of the hand during physical rehabilitation. The standard method uses a grip dynamometer which measures the force between the fingers and opposing thumb. The primary limitation of the grip dynamometer is the restriction of measurement to cylindrical grasps. Any deformation of the hand due to muscular or skeletal disease makes the grip dynamometer difficult or impossible to use. An alternative to the grip dynamometer is a sealed pneumatic object that can be gripped by the hand. Measurement of the internal pressure in the object can be related to the grip force. In this paper, we analyze such a pneumatic pressure sensing object for hand grip assessment and also describe an easy fabrication of the grip sensor. The instrumented object presented in this paper is designed to assess both the maximal voluntary grip forces and continuous grip force to monitor control of hand function during exercise under instruction from a therapist. Potential uses of such a pneumatic pressure sensing object for hand grip are in physical rehabilitation of patients following paralysing illnesses like stroke and spinal cord injury.

SBAS-InSAR analysis of surface deformation at Mauna Loa and Kilauea volcanoes in Hawaii

USGS Publications Warehouse

Casu, F.; Lanari, Riccardo; Sansosti, E.; Solaro, G.; Tizzani, Pietro; Poland, M.; Miklius, Asta

2009-01-01

We investigate the deformation of Mauna Loa and K??lauea volcanoes, Hawai'i, by exploiting the advanced differential Synthetic Aperture Radar Interferometry (InSAR) technique referred to as the Small BAseline Subset (SBAS) algorithm. In particular, we present time series of line-of-sight (LOS) displacements derived from SAR data acquired by the ASAR instrument, on board the ENVISAT satellite, from the ascending (track 93) and descending (track 429) orbits between 2003 and 2008. For each coherent pixel of the radar images we compute time-dependent surface displacements as well as the average LOS deformation rate. Our results quantify, in space and time, the complex deformation of Mauna Loa and K??lauea volcanoes. The derived InSAR measurements are compared to continuous GPS data to asses the quality of the SBAS-InSAR products. ??2009 IEEE.

Improving hand hygiene in a paediatric hospital: a multimodal quality improvement approach.

PubMed

Jamal, Ahmed; O'Grady, G; Harnett, E; Dalton, D; Andresen, D

2012-02-01

Effective hand hygiene has long been recognised as an important way to reduce the transmission of bacterial and viral pathogens in healthcare settings. However, many studies have shown that adherence to hand hygiene remains low, and improvement efforts have often not delivered sustainable results. The Children's Hospital at Westmead is the largest tertiary paediatric hospital in Sydney, Australia. The hospital participated in a state-wide 'Clean hands save lives' campaign which was initiated in 2006. Strong leadership, good stakeholder engagement, readily accessible alcohol-based hand rub at the point of patient care, a multifaceted education programme, monitoring of staff, adherence to recommended hand hygiene practices and contemporaneous feedback of performance data have significantly improved and maintained compliance with hand hygiene. Hand hygiene compliance has increased from 23% in 2006 to 87% in 2011 (p<0.001). Sustained improvement in compliance with hand hygiene has been evident in the last 4 years. A decline in a set of hospital-acquired infections (including rotavirus, multiresistant organism transmission, and nosocomial bacteraemia) has also been noted as hand hygiene rates have improved. Monthly usage of alcohol-based hand rub has increased from 16 litres/1000 bed days to 51 litres/1000 bed days during this same period. This project has delivered sustained improvement in hand hygiene compliance by establishing a framework of multimodal evidence-based strategies.

Foot deformities in Renaissance paintings. A mystery of symbolism, artistic licence, illusion and true representation in five renowned Renaissance painters.

PubMed

Lazzeri, D; Castello, M F; Grassetti, L; Dashti, T; Zhang, Y X; Persichetti, P

2015-01-01

Although Renaissance artists were skilled in representing normal anatomy, a close look at some paintings reveals anatomical variations in the depiction of the feet of human figures. A systematic review has identified 25 paintings by five artists in which the presumptive medico-artistic diagnosis of congenital or acquired foot deformity seems to be varyingly present. The connection between these five painters and what factors have influenced artists' style in the depiction of such deformities is discussed. The possible iconography and medical-historical meaning of such variations, as well as the possibility of artistic licence and real representation that drove the painters to depict these deformities, is explored and debated.

Early diagnosis of diabetic vascular complications: impairment of red blood cell deformability

NASA Astrophysics Data System (ADS)

Shin, Sehyun; Ku, Yunhee; Park, Cheol-Woo; Suh, Jang-Soo

2006-02-01

Reduced deformability of red blood cells (RBCs) may play an important role on the pathogenesis of chronic vascular complications of diabetes mellitus. However, available techniques for measuring RBC deformability often require washing process after each measurement, which is not optimal for day-to-day clinical use at point of care. The objectives of the present study are to develop a device and to delineate the correlation of impaired RBC deformability with diabetic nephropathy. We developed a disposable ektacytometry to measure RBC deformability, which adopted a laser diffraction technique and slit rheometry. The essential features of this design are its simplicity (ease of operation and no moving parts) and a disposable element which is in contact with the blood sample. We studied adult diabetic patients divided into three groups according to diabetic complications. Group I comprised 57 diabetic patients with normal renal function. Group II comprised 26 diabetic patients with chronic renal failure (CRF). Group III consisted of 30 diabetic subjects with end-stage renal disease (ESRD) on hemodialysis. According to the renal function for the diabetic groups, matched non-diabetic groups were served as control. We found substantially impaired red blood cell deformability in those with normal renal function (group I) compared to non-diabetic control (P = 0.0005). As renal function decreases, an increased impairment in RBC deformability was found. Diabetic patients with chronic renal failure (group II) when compared to non-diabetic controls (CRF) had an apparently greater impairment in RBC deformability (P = 0.07). The non-diabetic cohort (CRF), on the other hand, manifested significant impairment in red blood cell deformability compared to healthy control (P = 0.0001). The newly developed slit ektacytometer can measure the RBC deformability with ease and accuracy. In addition, progressive impairment in cell deformability is associated with renal function loss in all

The Art and Science of Photography in Hand Surgery

PubMed Central

Wang, Keming; Kowalski, Evan J.; Chung, Kevin C.

2013-01-01

High-quality medical photography plays an important role in teaching and demonstrating the functional capacity of the hands, as well as in medicolegal documentation. Obtaining standardized, high-quality photographs is now an essential component of many surgery practices. The importance of standardized photography in facial and cosmetic surgery has been well documented in previous studies, but no studies have thoroughly addressed the details of photography for hand surgery. In this paper, we will provide a set of guidelines and basic camera concepts for different scenarios to help hand surgeons obtain appropriate and informative high quality photographs. A camera used for medical photography should come equipped with a large sensor size and an optical zoom lens with a focal length ranging anywhere from 14-75mm. In a clinic or office setting, we recommend six standardized views of the hand and four views for the wrist, and additional views should be taken for tendon ruptures, nerve injuries, or other deformities of the hand. For intra-operative pictures, the camera operator should understand the procedure and pertinent anatomy in order to properly obtain high-quality photographs. When digital radiographs are not available, and radiographic film must be photographed, it is recommended to reduce the exposure and change the color mode to black and white to obtain the best possible pictures. The goal of medical photography is to present the subject in an accurate and precise fashion. PMID:23755927

Automated registration of large deformations for adaptive radiation therapy of prostate cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Godley, Andrew; Ahunbay, Ergun; Peng Cheng

2009-04-15

Available deformable registration methods are often inaccurate over large organ variation encountered, for example, in the rectum and bladder. The authors developed a novel approach to accurately and effectively register large deformations in the prostate region for adaptive radiation therapy. A software tool combining a fast symmetric demons algorithm and the use of masks was developed in C++ based on ITK libraries to register CT images acquired at planning and before treatment fractions. The deformation field determined was subsequently used to deform the delivered dose to match the anatomy of the planning CT. The large deformations involved required that themore » bladder and rectum volume be masked with uniform intensities of -1000 and 1000 HU, respectively, in both the planning and treatment CTs. The tool was tested for five prostate IGRT patients. The average rectum planning to treatment contour overlap improved from 67% to 93%, the lowest initial overlap is 43%. The average bladder overlap improved from 83% to 98%, with a lowest initial overlap of 60%. Registration regions were set to include a volume receiving 4% of the maximum dose. The average region was 320x210x63, taking approximately 9 min to register on a dual 2.8 GHz Linux system. The prostate and seminal vesicles were correctly placed even though they are not masked. The accumulated doses for multiple fractions with large deformation were computed and verified. The tool developed can effectively supply the previously delivered dose for adaptive planning to correct for interfractional changes.« less

A mechatronics platform to study prosthetic hand control using EMG signals.

PubMed

Geethanjali, P

2016-09-01

In this paper, a low-cost mechatronics platform for the design and development of robotic hands as well as a surface electromyogram (EMG) pattern recognition system is proposed. This paper also explores various EMG classification techniques using a low-cost electronics system in prosthetic hand applications. The proposed platform involves the development of a four channel EMG signal acquisition system; pattern recognition of acquired EMG signals; and development of a digital controller for a robotic hand. Four-channel surface EMG signals, acquired from ten healthy subjects for six different movements of the hand, were used to analyse pattern recognition in prosthetic hand control. Various time domain features were extracted and grouped into five ensembles to compare the influence of features in feature-selective classifiers (SLR) with widely considered non-feature-selective classifiers, such as neural networks (NN), linear discriminant analysis (LDA) and support vector machines (SVM) applied with different kernels. The results divulged that the average classification accuracy of the SVM, with a linear kernel function, outperforms other classifiers with feature ensembles, Hudgin's feature set and auto regression (AR) coefficients. However, the slight improvement in classification accuracy of SVM incurs more processing time and memory space in the low-level controller. The Kruskal-Wallis (KW) test also shows that there is no significant difference in the classification performance of SLR with Hudgin's feature set to that of SVM with Hudgin's features along with AR coefficients. In addition, the KW test shows that SLR was found to be better in respect to computation time and memory space, which is vital in a low-level controller. Similar to SVM, with a linear kernel function, other non-feature selective LDA and NN classifiers also show a slight improvement in performance using twice the features but with the drawback of increased memory space requirement and time

MetaSensing's FastGBSAR: ground based radar for deformation monitoring

NASA Astrophysics Data System (ADS)

Rödelsperger, Sabine; Meta, Adriano

2014-10-01

The continuous monitoring of ground deformation and structural movement has become an important task in engineering. MetaSensing introduces a novel sensor system, the Fast Ground Based Synthetic Aperture Radar (FastGBSAR), based on innovative technologies that have already been successfully applied to airborne SAR applications. The FastGBSAR allows the remote sensing of deformations of a slope or infrastructure from up to a distance of 4 km. The FastGBSAR can be setup in two different configurations: in Real Aperture Radar (RAR) mode it is capable of accurately measuring displacements along a linear range profile, ideal for monitoring vibrations of structures like bridges and towers (displacement accuracy up to 0.01 mm). Modal parameters can be determined within half an hour. Alternatively, in Synthetic Aperture Radar (SAR) configuration it produces two-dimensional displacement images with an acquisition time of less than 5 seconds, ideal for monitoring areal structures like dams, landslides and open pit mines (displacement accuracy up to 0.1 mm). The MetaSensing FastGBSAR is the first ground based SAR instrument on the market able to produce two-dimensional deformation maps with this high acquisition rate. By that, deformation time series with a high temporal and spatial resolution can be generated, giving detailed information useful to determine the deformation mechanisms involved and eventually to predict an incoming failure. The system is fully portable and can be quickly installed on bedrock or a basement. The data acquisition and processing can be fully automated leading to a low effort in instrument operation and maintenance. Due to the short acquisition time of FastGBSAR, the coherence between two acquisitions is very high and the phase unwrapping is simplified enormously. This yields a high density of resolution cells with good quality and high reliability of the acquired deformations. The deformation maps can directly be used as input into an Early

Fault architecture and deformation processes within poorly lithified rift sediments, Central Greece

NASA Astrophysics Data System (ADS)

Loveless, Sian; Bense, Victor; Turner, Jenni

2011-11-01

Deformation mechanisms and resultant fault architecture are primary controls on the permeability of faults in poorly lithified sediments. We characterise fault architecture using outcrop studies, hand samples, thin sections and grain-size data from a minor (1-10 m displacement) normal-fault array exposed within Gulf of Corinth rift sediments, Central Greece. These faults are dominated by mixed zones with poorly developed fault cores and damage zones. In poorly lithified sediment deformation is distributed across the mixed zone as beds are entrained and smeared. We find particulate flow aided by limited distributed cataclasis to be the primary deformation mechanism. Deformation may be localised in more competent sediments. Stratigraphic variations in sediment competency, and the subsequent alternating distributed and localised strain causes complexities within the mixed zone such as undeformed blocks or lenses of cohesive sediment, or asperities at the mixed zone/protolith boundary. Fault tip bifurcation and asperity removal are important processes in the evolution of these fault zones. Our results indicate that fault zone architecture and thus permeability is controlled by a range of factors including lithology, stratigraphy, cementation history and fault evolution, and that minor faults in poorly lithified sediment may significantly impact subsurface fluid flow.

Collision detection and modeling of rigid and deformable objects in laparoscopic simulator

NASA Astrophysics Data System (ADS)

Dy, Mary-Clare; Tagawa, Kazuyoshi; Tanaka, Hiromi T.; Komori, Masaru

2015-03-01

Laparoscopic simulators are viable alternatives for surgical training and rehearsal. Haptic devices can also be incorporated with virtual reality simulators to provide additional cues to the users. However, to provide realistic feedback, the haptic device must be updated by 1kHz. On the other hand, realistic visual cues, that is, the collision detection and deformation between interacting objects must be rendered at least 30 fps. Our current laparoscopic simulator detects the collision between a point on the tool tip, and on the organ surfaces, in which haptic devices are attached on actual tool tips for realistic tool manipulation. The triangular-mesh organ model is rendered using a mass spring deformation model, or finite element method-based models. In this paper, we investigated multi-point-based collision detection on the rigid tool rods. Based on the preliminary results, we propose a method to improve the collision detection scheme, and speed up the organ deformation reaction. We discuss our proposal for an efficient method to compute simultaneous multiple collision between rigid (laparoscopic tools) and deformable (organs) objects, and perform the subsequent collision response, with haptic feedback, in real-time.

Vertebral column deformities in white-beaked dolphins from the eastern North Atlantic.

PubMed

Bertulli, Chiara G; Galatius, Anders; Kinze, Carl C; Rasmussen, Marianne H; Deaville, Rob; Jepson, Paul; Vedder, Elisabeth J; Sánchez Contreras, Guillermo J; Sabin, Richard C; Watson, Alastair

2015-09-17

Five white-beaked dolphins Lagenorhynchus albirostris with outwardly vertebral kyphosis, kyphoscoliosis or lordosis were identified during a photo-identification survey of over 400 individuals (2002-2013) in Faxaflói and Skjálfandi Bays, Iceland. In addition, 3 stranding reports from Denmark, The Netherlands and the UK were analysed, providing both external observation and post mortem details of axial deviations of the vertebral column in this species. Two of the free-ranging cases and 2 of the stranded specimens appeared to have an acquired disease, either as a direct result of trauma, or indirectly from trauma/wound and subsequent infection and bony proliferation, although we were unable to specifically identify the causes. Our data represent a starting point to understand vertebral column deformations and their implications in white-beaked dolphins from the eastern North Atlantic. We recommend for future necropsy cases to conduct macro- and microscopic evaluation of muscle from both sides of the deformed region, in order to assess chronic or acute conditions related to the vertebral deformations and cause of death.

Handedness and spinal deformity.

PubMed

Goldberg, C J; Moore, D P; Fogarty, E E; Dowling, F E

2006-01-01

Biological lateralisation is clearly manifest in scoliosis, yet its relevance is unclear. Goldberg et al. (Spine. 15(2):61-64. 1990) found an association between curve pattern and hand-preference in a screened population, but no increase in sinistrality. Milenkovic et al, (European Journal of Epidemiology, 19:969-972,2004) concluded left-handedness was a risk factor in a screened group. The database was reassessed to determine whether clinically significant scoliosis was associated with sinistrality or differed from the population norm of 10%. Patients attending the scoliosis clinic were asked their preferred writing hand. 1,636 patients were identified with complete data. Overall, left handedness occurred in 11.5%, greater than the general population (p=0.04) Left hand preference was found to be increased in boys with infantile idiopathic scoliosis and in girls with infantile, juvenile, congenital and syndromic scoliosis, but was reduced in girls with adolescent idiopathic scoliosis. Scoliosis lateralisation was random in infantile and congenital scoliosis, while left curve patterns were decreased in girls with juvenile idiopathic scoliosis and increased in boys with syndromic scoliosis. Curve pattern and handedness correlated in asymmetry in boys and girls and in girls with radiologically confirmed adolescent idiopathic scoliosis, but not in any other type. This study cannot confirm findings of left-handedness as a risk factor for spinal deformity. Its incidence is reduced in girls with adolescent idiopathic scoliosis, and the increased sinistrality in infantile scoliosis is not a new finding (Rauterberg & Tonnis Ger. Z.Orthop. 109(14):676-689. 1971). Lateralisation is undoubtedly a factor in scoliosis, but does not have a simple causal relationship, probably deriving from the underlying scoliotic process, rather than contributing to it.

Combined Spring and Deltoid Ligament Repair in Adult-Acquired Flatfoot.

PubMed

Nery, Caio; Lemos, André Vitor Kerber C; Raduan, Fernando; Mansur, Nacime Salomão B; Baumfeld, Daniel

2018-04-01

Adult-acquired flatfoot deformity (AAFD) is usually due to a combination of mechanical failure of the osteoligamentous complex that maintains the medial longitudinal arch of the foot and attenuation or complete tear of the posterior tibial tendon. Magnetic resonance imaging studies in patients with flatfoot deformities have reported the posterior tibial tendon to be pathologic in up to 100% of patients, the spring ligament in up to 87%, and the deltoid ligament in 33%. Many studies in the literature describe reconstruction of the spring ligament or the deltoid ligament associated with AAFD, but there is no study in which both (spring and deltoid) ligaments are reconstructed at the same time. We describe a novel technique to reconstruct the deltoid ligament and the spring ligament at the same time. We described the technique and evaluated 10 consecutive patients with AAFD and insufficient ankle and midfoot ligaments. We found no postoperative complications, stiffness, or loss of correction. We present a novel technique to reconstruct the failed deltoid and spring ligament during flatfoot correction. It is unique in that it uses internal brace augmentation with FiberTape ® to help and protect the soft tissue healing. Level IV, retrospective case series.

Application of Time Series Insar Technique for Deformation Monitoring of Large-Scale Landslides in Mountainous Areas of Western China

NASA Astrophysics Data System (ADS)

Qu, T.; Lu, P.; Liu, C.; Wan, H.

2016-06-01

Western China is very susceptible to landslide hazards. As a result, landslide detection and early warning are of great importance. This work employs the SBAS (Small Baseline Subset) InSAR Technique for detection and monitoring of large-scale landslides that occurred in Li County, Sichuan Province, Western China. The time series INSAR is performed using descending scenes acquired from TerraSAR-X StripMap mode since 2014 to get the spatial distribution of surface displacements of this giant landslide. The time series results identify the distinct deformation zone on the landslide body with a rate of up to 150mm/yr. The deformation acquired by SBAS technique is validated by inclinometers from diverse boreholes of in-situ monitoring. The integration of InSAR time series displacements and ground-based monitoring data helps to provide reliable data support for the forecasting and monitoring of largescale landslide.

Competing Grain Boundary and Interior Deformation Mechanisms with Varying Sizes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Wei; Gao, Yanfei; Nieh, T. G.

In typical coarse-grained alloys, the dominant plastic deformations are dislocation gliding or climbing, and material strengths can be tuned by dislocation interactions with grain boundaries, precipitates, solid solutions, and other defects. With the reduction of grain size, the increase of material strengths follows the classic Hall-Petch relationship up to nano-grained materials. Even at room temperatures, nano-grained materials exhibit strength softening, or called the inverse Hall-Petch effect, as grain boundary processes take over as the dominant deformation mechanisms. On the other hand, at elevated temperatures, grain boundary processes compete with grain interior deformation mechanisms over a wide range of the appliedmore » stress and grain sizes. This book chapter reviews and compares the rate equation model and the microstructure-based finite element simulations. The latter explicitly accounts for the grain boundary sliding, grain boundary diffusion and migration, as well as the grain interior dislocation creep. Therefore the explicit finite element method has clear advantages in problems where microstructural heterogeneities play a critical role, such as in the gradient microstructure in shot peening or weldment. Furthermore, combined with the Hall-Petch effect and its breakdown, the above competing processes help construct deformation mechanism maps by extending from the classic Frost-Ashby type to the ones with the dependence of grain size.« less

A cam deformity is gradually acquired during skeletal maturation in adolescent and young male soccer players: a prospective study with minimum 2-year follow-up.

PubMed

Agricola, Rintje; Heijboer, Marinus P; Ginai, Abida Z; Roels, Pauline; Zadpoor, Amir A; Verhaar, Jan A N; Weinans, Harrie; Waarsing, Jan H

2014-04-01

A cam deformity is a major risk factor for hip osteoarthritis, and its formation is thought to be influenced by high-impact sporting activities during growth. To (1) prospectively study whether a cam deformity can evolve over time in adolescents and whether its formation only occurs during skeletal maturation and (2) examine whether clinical or radiographic features can predict the formation of a cam deformity. Cohort study (prognosis); Level of evidence, 2. Preprofessional soccer players (N = 63; mean age, 14.43 years; range, 12-19 years) participated both at baseline and follow-up (mean follow-up, 2.4 ± 0.06 years). At both time points, standardized anteroposterior and frog-leg lateral radiographs were obtained. For each hip, the α angle was measured, and the anterosuperior head-neck junction was classified by a 3-point visual system as normal, flattened, or having a prominence. Differences between baseline and follow-up values for the α angle and the prevalence of each visual hip classification were calculated. Additionally, the amount of internal hip rotation, growth plate extension into the neck, and neck shaft angle were determined. Overall, there was a significant increase in the prevalence of a cam deformity during follow-up. In boys aged 12 and 13 years at baseline, the prevalence of a flattened head-neck junction increased significantly during follow-up (13.6% to 50.0%; P = .002). In all hips with an open growth plate at baseline, the prevalence of a prominence increased from 2.1% to 17.7% (P = .002). After closure of the proximal femoral growth plate, there was no significant increase in the prevalence or increase in severity of a cam deformity. The α angle increased significantly from 59.4° at baseline to 61.3° at follow-up (P = .018). The amount of growth plate extension was significantly associated with the α angle and hip classification (P = .001). A small neck shaft angle and limited internal rotation were associated with cam deformities and

Structural control of elastic moduli in ferrogels and the importance of non-affine deformations

NASA Astrophysics Data System (ADS)

Pessot, Giorgio; Cremer, Peet; Borin, Dmitry Y.; Odenbach, Stefan; Löwen, Hartmut; Menzel, Andreas M.

2014-09-01

One of the central appealing properties of magnetic gels and elastomers is that their elastic moduli can reversibly be adjusted from outside by applying magnetic fields. The impact of the internal magnetic particle distribution on this effect has been outlined and analyzed theoretically. In most cases, however, affine sample deformations are studied and often regular particle arrangements are considered. Here we challenge these two major simplifications by a systematic approach using a minimal dipole-spring model. Starting from different regular lattices, we take into account increasingly randomized structures, until we finally investigate an irregular texture taken from a real experimental sample. On the one hand, we find that the elastic tunability qualitatively depends on the structural properties, here in two spatial dimensions. On the other hand, we demonstrate that the assumption of affine deformations leads to increasingly erroneous results the more realistic the particle distribution becomes. Understanding the consequences of the assumptions made in the modeling process is important on our way to support an improved design of these fascinating materials.

Study of the deformation in Central Afar using InSAR NSBAS chain

NASA Astrophysics Data System (ADS)

Deprez, A.; Doubre, C.; Grandin, R.; Saad, I.; Masson, F.; Socquet, A.

2013-12-01

The Afar Depression (East Africa) connects all three continental plates of Arabia, Somalia and Nubia plates. For over 20 Ma, the divergent motion of these plates has led to the formation of large normal faults building tall scarps between the high plateaus and the depression, and the development of large basins and an incipient seafloor spreading along a series of active volcano-tectonic rift segments within the depression. The space-time evolution of the active surface deformation over the whole Afar region remains uncertain. Previous tectonic and geodetic studies confirm that a large part of the current deformation is concentrated along these segments. However, the amount of extension accommodated by other non-volcanic basins and normal faulting remains unclear, despite significant micro-seismic activity. Due to the active volcanism, large transient displacements related to dyking sequence, notably in the Manda Hararo rift (2005-2010), increase the difficulty to characterize the deformation field over simple time and space scales. In this study, we attempt to obtain a complete inventory of the deformation within the whole Afar Depression and to understand the associated phenomena, which occurred in this singular tectonic environment. We study in particular, the behavior of the structures activated during the post-dyking stage of the rift segments. For this purpose, we conduct a careful processing of a large set of SAR ENVISAT images over the 2004-2010 period, we also use previous InSAR results and GPS data from permanent stations and from campaigns conducted in 1999, 2003, 2010, 2012 within a GPS network particularly dense along the Asal-Ghoubbet segment. In one hand, in the western part of Afar, the far-field response of the 2005-2010 dyke sequence appears to be the dominant surface motion on the mean velocity field. In an other hand, more eastward across the Asal-Ghoubbet rift, strong gradients of deformation are observed. The time series analysis of both In

Comparison of molecular dynamics and superfamily spaces of protein domain deformation

PubMed Central

Velázquez-Muriel, Javier A; Rueda, Manuel; Cuesta, Isabel; Pascual-Montano, Alberto; Orozco, Modesto; Carazo, José-María

2009-01-01

Background It is well known the strong relationship between protein structure and flexibility, on one hand, and biological protein function, on the other hand. Technically, protein flexibility exploration is an essential task in many applications, such as protein structure prediction and modeling. In this contribution we have compared two different approaches to explore the flexibility space of protein domains: i) molecular dynamics (MD-space), and ii) the study of the structural changes within superfamily (SF-space). Results Our analysis indicates that the MD-space and the SF-space display a significant overlap, but are still different enough to be considered as complementary. The SF-space space is wider but less complex than the MD-space, irrespective of the number of members in the superfamily. Also, the SF-space does not sample all possibilities offered by the MD-space, but often introduces very large changes along just a few deformation modes, whose number tend to a plateau as the number of related folds in the superfamily increases. Conclusion Theoretically, we obtained two conclusions. First, that function restricts the access to some flexibility patterns to evolution, as we observe that when a superfamily member changes to become another, the path does not completely overlap with the physical deformability. Second, that conformational changes from variation in a superfamily are larger and much simpler than those allowed by physical deformability. Methodologically, the conclusion is that both spaces studied are complementary, and have different size and complexity. We expect this fact to have application in fields as 3D-EM/X-ray hybrid models or ab initio protein folding. PMID:19220918

Deformation Partitioning: The Missing Link Between Outcrop-Scale Observations And Orogen-Scale Processes

NASA Astrophysics Data System (ADS)

Attia, S.; Paterson, S. R.; Jiang, D.; Miller, R. B.

2017-12-01

Structural studies of orogenic deformation fields are mostly based on small-scale structures ubiquitous in field exposures, hand samples, and under microscopes. Relating deformation histories derived from such structures to changing lithospheric-scale deformation and boundary conditions is not trivial due to vast scale separation (10-6 107 m) between characteristic lengths of small-scale structures and lithospheric plates. Rheological heterogeneity over the range of orogenic scales will lead to deformation partitioning throughout intervening scales of structural development. Spectacular examples of structures documenting deformation partitioning are widespread within hot (i.e., magma-rich) orogens such as the well-studied central Sierra Nevada and Cascades core of western North America: (1) deformation partitioned into localized, narrow, triclinic shear zones separated by broad domains of distributed pure shear at micro- to 10 km scales; (2) deformation partitioned between plutons and surrounding metamorphic host rocks as shown by pluton-wide magmatic fabrics consistently oriented differently than coeval host rock fabrics; (3) partitioning recorded by different fabric intensities, styles, and orientations established from meter-scale grid mapping to 100 km scale domainal analyses; and (4) variations in the causes of strain and kinematics within fold-dominated domains. These complex, partitioned histories require synthesized mapping, geochronology, and structural data at all scales to evaluate partitioning and in the absence of correct scaling can lead to incorrect interpretations of histories. Forward modeling capable of addressing deformation partitioning in materials containing multiple scales of rheologically heterogeneous elements of varying characteristic lengths provides the ability to upscale the large synthesized datasets described above to plate-scale tectonic processes and boundary conditions. By comparing modeling predictions from the recently developed

AFM study of the plastic deformation behavior of poly-synthetically-twinned (PST) titanium aluminide crystals

NASA Astrophysics Data System (ADS)

Chen, Yali

The plastic deformation behavior of PST TiAl crystals was investigated using AFM techniques to reveal the effects of lamellar structure on the deform mechanisms of two-phase TiAl materials. PST crystals with a nominal composition of Ti52Al48 (atomic percent) were grown by the floating zone method and at various orientations deformed in compression at room temperature. Atomic Force Microscopy (AFM) was employed to investigate the deformation structure on the free surfaces. The deformation of the PST crystals is highly anisotropic and the deformation mechanism changes dramatically with sample orientation. When the angle between the loading axis and the lamellar interfaces is below 20°, the gamma lamellae deform by dislocation slip and twinning on planes oblique to the lamellar interfaces, but the Burgers vectors or the resultant shear vectors are parallel to the lamellar interfaces inside each lamella. When the angle is between 20° and 80° the gamma phase deforms by shear on planes parallel to the lamellar interfaces. Some domains deform by a combination of ordinary dislocation slip and twinning. In the domains where twinning cannot be activated, slip occurs by ordinary dislocations or superdislocations. When the loading axis is nearly perpendicular to the lamellar interfaces ordinary dislocation slip and twinning on slip planes inclined with the lamellar interfaces are dominant and the shear is trans-lamellar. The three deformation modes are termed as A, B and N type deformation modes respectively. In the A type mode the alpha2 lamellae concomitantly deform by prismatic slip. In the other two modes, the alpha2 phase does not deform and acts as strong obstacles to the transfer of deformation. Abundant misfit dislocations are emitted from the lamellar interfaces which is beneficial for the plastic deformation. On the other hand, the lamellar interfaces strongly impede trans-lamellar deformation and channel the deformation inside each lamella. The inhomogeneous

ASAR images a diverse set of deformation patterns at Kilauea volcano, Hawai'i

USGS Publications Warehouse

Poland, Michael P.

2007-01-01

Since 2003, 27 independent look angles have been acquired by ENVISAT’s Advanced Synthetic Aperture Radar (ASAR) instrument over the island of Hawai`i, allowing for the formation of thousands of interferograms showing deformation of the ground surface. On Kīlauea volcano, a transition from minor to broad-scale summit inflation was observed by interferograms that span 2003 to 2006. In addition, radar interferometry (InSAR) observations of Kīlauea led to the discovery of several previously unknown areas of localized subsidence in the caldera and along the volcano’s east rift zone. These features are probably caused by the cooling and contraction of accumulated lavas. After November 2005, a surface instability near the point that lava entered the ocean on the south flank of Kīlauea was observed in interferograms. The motion is most likely a result of unbuttressing of a portion of the coast following the collapse of a large lava delta in November 2005. InSAR data can also be used to map lava flow development over time, providing ~30 m spatial resolution maps at approximately monthly intervals. Future applications of InSAR to Kīlauea will probably result in more discoveries and insights, both as the style of volcano deformation changes and as data from new instruments are acquired.

Real-Time Control of an Exoskeleton Hand Robot with Myoelectric Pattern Recognition.

PubMed

Lu, Zhiyuan; Chen, Xiang; Zhang, Xu; Tong, Kay-Yu; Zhou, Ping

2017-08-01

Robot-assisted training provides an effective approach to neurological injury rehabilitation. To meet the challenge of hand rehabilitation after neurological injuries, this study presents an advanced myoelectric pattern recognition scheme for real-time intention-driven control of a hand exoskeleton. The developed scheme detects and recognizes user's intention of six different hand motions using four channels of surface electromyography (EMG) signals acquired from the forearm and hand muscles, and then drives the exoskeleton to assist the user accomplish the intended motion. The system was tested with eight neurologically intact subjects and two individuals with spinal cord injury (SCI). The overall control accuracy was [Formula: see text] for the neurologically intact subjects and [Formula: see text] for the SCI subjects. The total lag of the system was approximately 250[Formula: see text]ms including data acquisition, transmission and processing. One SCI subject also participated in training sessions in his second and third visits. Both the control accuracy and efficiency tended to improve. These results show great potential for applying the advanced myoelectric pattern recognition control of the wearable robotic hand system toward improving hand function after neurological injuries.

Structural deformation measurement via efficient tensor polynomial calibrated electro-active glass targets

NASA Astrophysics Data System (ADS)

Gugg, Christoph; Harker, Matthew; O'Leary, Paul

2013-03-01

This paper describes the physical setup and mathematical modelling of a device for the measurement of structural deformations over large scales, e.g., a mining shaft. Image processing techniques are used to determine the deformation by measuring the position of a target relative to a reference laser beam. A particular novelty is the incorporation of electro-active glass; the polymer dispersion liquid crystal shutters enable the simultaneous calibration of any number of consecutive measurement units without manual intervention, i.e., the process is fully automatic. It is necessary to compensate for optical distortion if high accuracy is to be achieved in a compact hardware design where lenses with short focal lengths are used. Wide-angle lenses exhibit significant distortion, which are typically characterized using Zernike polynomials. Radial distortion models assume that the lens is rotationally symmetric; such models are insufficient in the application at hand. This paper presents a new coordinate mapping procedure based on a tensor product of discrete orthogonal polynomials. Both lens distortion and the projection are compensated by a single linear transformation. Once calibrated, to acquire the measurement data, it is necessary to localize a single laser spot in the image. For this purpose, complete interpolation and rectification of the image is not required; hence, we have developed a new hierarchical approach based on a quad-tree subdivision. Cross-validation tests verify the validity, demonstrating that the proposed method accurately models both the optical distortion as well as the projection. The achievable accuracy is e <= +/-0.01 [mm] in a field of view of 150 [mm] x 150 [mm] at a distance of the laser source of 120 [m]. Finally, a Kolmogorov Smirnov test shows that the error distribution in localizing a laser spot is Gaussian. Consequently, due to the linearity of the proposed method, this also applies for the algorithm's output. Therefore, first

Tensile deformation and recovery kinetics of Alloy 690

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, C.F.; Mayo, W.E.; Weissmann, S.

1992-07-01

The effect of carbon content, grain size and thermal history on the deformation behavior of nickel-base Alloy 690 has been investigated. Carbon content effects the yield strength of Mill Annealed (MA) material, but has no effect in Thermally Treated (TT) material. Also, no effect of carbon content on the workhardening rate was seen in either material. There was an effect of grain size as expected. An interesting aspect of this work showed that TT material consistently has a slightly higher Young's modulus than the MA. As deformation moves into the plastic regime, the TT material displays a two stage hardeningmore » process. This consists of a low workhardening rate (n = 0.05), followed by a transition to the more normal workhardening rate (n=0.35). The MA material, on the other hand, does not exhibit the low n region. This unusual deformation behavior is attributable to the presence of planar slip which initiates at the grain boundary over the strain range of 0.2 to 0.7%. These observations are useful to explain the unexpectedly fast strain relaxation behavior seen in this alloy. The recovery kinetics of the alloy have also been studied. Rapid recovery with an activation energy of approximately 5.3 kj/mol occurs when the deformation level is low. This was attributed to a grain boundary self diffusion process. At higher strain levels, recovery is much slower with an activation energy of approximately 14 kJ/mol. This process was attributable to bulk diffusion. Based on TEM and X-ray rocking curve measurements, these results have been explained.« less

Global synthesis of volcano deformation: Results of the Volcano Deformation Task Force

NASA Astrophysics Data System (ADS)

Pritchard, M. E.; Jay, J.; Biggs, J.; Ebmeier, S. K.; Delgado, F.

2013-12-01

Ground deformation in volcanic regions is being observed more frequently -- the number of known deforming volcanoes has increased from 44 in 1997 to more than 210 in 2013 thanks in large part thanks to the availability of satellite InSAR observations. With the launch of new SAR satellites in the coming years devoted to global deformation monitoring, the number of well-studied episodes of volcano deformation will continue to increase. But evaluating the significance of the observed deformation is not always straightforward -- how often do deformation episodes lead to eruption? Are there certain characteristics of the deformation or the volcano that make the linkage between deformation and eruption more robust -- for example the duration or magnitude of the ground deformation and/or the composition and tectonic setting of the volcano? To answer these questions, a global database of volcano deformation events is needed. Recognizing the need for global information on volcano deformation and the opportunity to address it with InSAR and other techniques, we formed the Volcano Deformation Database Task force as part of Global Volcano Model. The three objectives of our organization are: 1) to compile deformation observations of all volcanoes globally into appropriate formats for WOVOdat and the Global Volcanism Program of the Smithsonian Institution. 2) document any relation between deformation events and eruptions for the Global assessment of volcanic hazard and risk report for 2015 (GAR15) for the UN. 3) to better link InSAR and other remote sensing observations to volcano observatories. We present the first results from our global study of the relation between deformation and eruptions, including case studies of particular eruptions. We compile a systematically-observed catalog of >500 volcanoes with observation windows up to 20 years. Of 90 volcanoes showing deformation, 40 erupted. The positive predictive value (PPV = 0.44) linking deformation and eruption on this

Co- and post-seismic deformation for the 2014 Napa Valley Earthquake from Sentinel-1A interferometry

NASA Astrophysics Data System (ADS)

Elliott, J. R.; Wright, T. J.; Elliott, A. J.; González, P. J.; Hooper, A. J.; Larsen, Y.; Marinkovic, P.; Plain, M.; Walters, R. J.

2014-12-01

Here we present analysis of co- and post-seismic deformation for the 24 August 2014 Napa Valley Earthquake derived from Sentinel-1A interferometry. We use these to derive the co-seismic slip distribution and map the evolution of post-seismic afterslip. The 24 August 2014 Napa Valley earthquake was the first earthquake for which surface deformation was measured by Sentinel-1A, a new radar satellite launched by the European Space Agency on 3 April 2014, and operated by the European Commission's Copernicus program. Sentinel-1A reached its final operational orbit on 7 August, and fortuitously acquired a pre-earthquake image of the San Francisco Bay area on that day in StripMap mode. By comparing it with an image acquired on 31 August, we formed a co-seismic interferogram, which reveals the surface deformation that occurred during the earthquake and the first 7 days of the post-seismic period. We use this to constrain a simple elastic model of the co-seismic slip distribution; preliminary inversion results show that the slip at depth reached a peak of >1.5 m at a depth of ~4 km. Following the earthquake, Sentinel-1A has acquired further acquisitions in both StripMap and Interferometric Wide Swath modes. The first 12-day post-seismic StripMap interferogram shows a sharp discontinuity along the entire fault rupture, consistent with field observations of rapid afterslip. We will use the full time series from August to December to measure the spatio-temporal behaviour of the afterslip, and discuss the implications for the frictional properties of the fault. The results from Napa point to an exciting and impactful future for the Sentinel-1 radar constellation. By mid-2014, Sentinel-1A will be acquiring data systematically over all the seismic belts, and the launch of Sentinel-1B in 2016 will increase the temporal frequency of acquisitions. The data will be available free of charge and will transform our ability to conduct tectonic geodesy, particularly in remote areas of the

Functionality predictors in acquired brain damage.

PubMed

Huertas Hoyas, E; Pedrero Pérez, E J; Águila Maturana, A M; García López-Alberca, S; González Alted, C

2015-01-01

Most individuals who have survived an acquired brain injury present consequences affecting the sensorimotor, cognitive, affective or behavioural components. These deficits affect the proper performance of daily living activities. The aim of this study is to identify functional differences between individuals with unilateral acquired brain injury using functional independence, capacity, and performance of daily activities. Descriptive cross-sectional design with a sample of 58 people, with right-sided injury (n=14 TBI; n=15 stroke) or left-sided injury (n = 14 TBI, n = 15 stroke), right handed, and with a mean age of 47 years and time since onset of 4 ± 3.65 years. The functional assessment/functional independence measure (FIM/FAM) and the International Classification of Functioning (ICF) were used for the study. The data showed significant differences (P<.000), and a large size effect (dr=0.78) in the cross-sectional estimates, and point to fewer restrictions for patients with a lesion on their right side. The major differences were in the variables 'speaking' and 'receiving spoken messages' (ICF variables), and 'Expression', 'Writing' and 'intelligible speech' (FIM/FAM variables). In the linear regression analysis, the results showed that only 4 FIM/FAM variables, taken together, predict 44% of the ICF variance, which measures the ability of the individual, and up to 52% of the ICF, which measures the individual's performance. Gait alone predicts a 28% of the variance. It seems that individuals with acquired brain injury in the left hemisphere display important differences regarding functional and communication variables. The motor aspects are an important prognostic factor in functional rehabilitation. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

WE-G-BRF-01: Adaptation to Intrafraction Tumor Deformation During Intensity-Modulated Radiotherapy: First Proof-Of-Principle Demonstration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ge, Y; OBrien, R; Shieh, C

2014-06-15

Purpose: Intrafraction tumor deformation limits targeting accuracy in radiotherapy and cannot be adapted to by current motion management techniques. This study simulated intrafractional treatment adaptation to tumor deformations using a dynamic Multi-Leaf Collimator (DMLC) tracking system during Intensity-modulated radiation therapy (IMRT) treatment for the first time. Methods: The DMLC tracking system was developed to adapt to the intrafraction tumor deformation by warping the planned beam aperture guided by the calculated deformation vector field (DVF) obtained from deformable image registration (DIR) at the time of treatment delivery. Seven single phantom deformation images up to 10.4 mm deformation and eight tumor systemmore » phantom deformation images up to 21.5 mm deformation were acquired and used in tracking simulation. The intrafraction adaptation was simulated at the DMLC tracking software platform, which was able to communicate with the image registration software, reshape the instantaneous IMRT field aperture and log the delivered MLC fields.The deformation adaptation accuracy was evaluated by a geometric target coverage metric defined as the sum of the area incorrectly outside and inside the reference aperture. The incremental deformations were arbitrarily determined to take place equally over the delivery interval. The geometric target coverage of delivery with deformation adaptation was compared against the delivery without adaptation. Results: Intrafraction deformation adaptation during dynamic IMRT plan delivery was simulated for single and system deformable phantoms. For the two particular delivery situations, over the treatment course, deformation adaptation improved the target coverage by 89% for single target deformation and 79% for tumor system deformation compared with no-tracking delivery. Conclusion: This work demonstrated the principle of real-time tumor deformation tracking using a DMLC. This is the first step towards the development

Assessment of 3D hydrologic deformation using GRACE and GPS

NASA Astrophysics Data System (ADS)

Watson, C. S.; Tregoning, P.; Fleming, K.; Burgette, R. J.; Featherstone, W. E.; Awange, J.; Kuhn, M.; Ramillien, G.

2009-12-01

Hydrological processes cause variations in gravitational potential and surface deformations, both of which are detectable with ever increasing precision using space geodetic techniques. By comparing the elastic deformation computed from continental water load estimates derived from the Gravity Recovery and Climate Experiment (GRACE), with three-dimensional surface deformation derived from GPS observations, there is clear potential to better understand global to regional hydrological processes, in addition to acquiring further insight into the systematic error contributions affecting each space geodetic technique. In this study, we compare elastic deformation derived from water load estimates taken from the CNES, CSR, GFZ and JPL time variable GRACE fields. We compare these surface displacements with those derived at a global network of GPS sites that have been homogeneously reprocessed in the GAMIT/GLOBK suite. We extend our comparison to include a series of different GPS solutions, with each solution only subtly different based on the methodology used to down weight the height component in realizing site coordinates on the terrestrial reference frame. Each of the GPS solutions incorporate modeling of atmospheric loading and utilization of the VMF1 and a priori zenith hydrostatic delays derived via ray tracing through ECMWF meteorological fields. The agreement between GRACE and GPS derived deformations is not limited to the vertical component, with excellent agreement in the horizontal component across areas where large hydrologic signals occur over broad spatial scales (with correlation in horizontal components as high as 0.9). Agreement is also observed at smaller scales, including across Europe. These comparisons assist in understanding the magnitude of current error contributions within both space geodetic techniques. With the emergence of homogeneously reprocessed GPS time series spanning the GRACE mission, this technique offers one possible means of

Using environmental engineering to increase hand hygiene compliance: a cross-over study protocol

PubMed Central

Schmidtke, Kelly Ann; Aujla, Navneet; Marshall, Tom; Hussain, Abid; Hodgkinson, Gerard P; Arheart, Kristopher; Marti, Joachim; Birnbach, David J; Vlaev, Ivo

2017-01-01

Introduction Compliance with hand hygiene recommendations in hospital is typically less than 50%. Such low compliance inevitably contributes to hospital-acquired infections that negatively affect patients’ well-being and hospitals’ finances. The design of the present study is predicated on the assumption that most people who fail to clean their hands are not doing so intentionally, they just forget. The present study will test whether psychological priming can be used to increase the number of people who clean their hands on entering a ward. Here, we present the protocol for this study. Methods and analysis The study will use a randomised cross-over design. During the study, each of four wards will be observed during four conditions: olfactory prime, visual prime, both primes and neither prime. Each condition will be experienced for 42 days followed by a 7-day washout period (total duration of trial=189 days). We will record the number of people who enter each ward and whether they clean their hands during observation sessions, the amount of cleaning material used from the dispensers each week and the number of hospital-acquired infections that occur in each period. The outcomes will be compared using a regression analysis. Following the initial trail, the most effective priming condition will be rolled out for 3 months in all the wards. Ethics and dissemination Research ethics approval was obtained from the South Central—Oxford C Research Ethics Committee (16/SC/0554), the Health Regulatory Authority and the sponsor. Trial registration number ISRCTN (15397624); Edge ID 86357. PMID:28893752

Mechanical Failure Mode of Metal Nanowires: Global Deformation versus Local Deformation

PubMed Central

Ho, Duc Tam; Im, Youngtae; Kwon, Soon-Yong; Earmme, Youn Young; Kim, Sung Youb

2015-01-01

It is believed that the failure mode of metal nanowires under tensile loading is the result of the nucleation and propagation of dislocations. Such failure modes can be slip, partial slip or twinning and therefore they are regarded as local deformation. Here we provide numerical and theoretical evidences to show that global deformation is another predominant failure mode of nanowires under tensile loading. At the global deformation mode, nanowires fail with a large contraction along a lateral direction and a large expansion along the other lateral direction. In addition, there is a competition between global and local deformations. Nanowires loaded at low temperature exhibit global failure mode first and then local deformation follows later. We show that the global deformation originates from the intrinsic instability of the nanowires and that temperature is a main parameter that decides the global or local deformation as the failure mode of nanowires. PMID:26087445

Predicting Welding Distortion in a Panel Structure with Longitudinal Stiffeners Using Inherent Deformations Obtained by Inverse Analysis Method

PubMed Central

Liang, Wei; Murakawa, Hidekazu

2014-01-01

Welding-induced deformation not only negatively affects dimension accuracy but also degrades the performance of product. If welding deformation can be accurately predicted beforehand, the predictions will be helpful for finding effective methods to improve manufacturing accuracy. Till now, there are two kinds of finite element method (FEM) which can be used to simulate welding deformation. One is the thermal elastic plastic FEM and the other is elastic FEM based on inherent strain theory. The former only can be used to calculate welding deformation for small or medium scale welded structures due to the limitation of computing speed. On the other hand, the latter is an effective method to estimate the total welding distortion for large and complex welded structures even though it neglects the detailed welding process. When the elastic FEM is used to calculate the welding-induced deformation for a large structure, the inherent deformations in each typical joint should be obtained beforehand. In this paper, a new method based on inverse analysis was proposed to obtain the inherent deformations for weld joints. Through introducing the inherent deformations obtained by the proposed method into the elastic FEM based on inherent strain theory, we predicted the welding deformation of a panel structure with two longitudinal stiffeners. In addition, experiments were carried out to verify the simulation results. PMID:25276856

Predicting welding distortion in a panel structure with longitudinal stiffeners using inherent deformations obtained by inverse analysis method.

PubMed

Liang, Wei; Murakawa, Hidekazu

2014-01-01

Welding-induced deformation not only negatively affects dimension accuracy but also degrades the performance of product. If welding deformation can be accurately predicted beforehand, the predictions will be helpful for finding effective methods to improve manufacturing accuracy. Till now, there are two kinds of finite element method (FEM) which can be used to simulate welding deformation. One is the thermal elastic plastic FEM and the other is elastic FEM based on inherent strain theory. The former only can be used to calculate welding deformation for small or medium scale welded structures due to the limitation of computing speed. On the other hand, the latter is an effective method to estimate the total welding distortion for large and complex welded structures even though it neglects the detailed welding process. When the elastic FEM is used to calculate the welding-induced deformation for a large structure, the inherent deformations in each typical joint should be obtained beforehand. In this paper, a new method based on inverse analysis was proposed to obtain the inherent deformations for weld joints. Through introducing the inherent deformations obtained by the proposed method into the elastic FEM based on inherent strain theory, we predicted the welding deformation of a panel structure with two longitudinal stiffeners. In addition, experiments were carried out to verify the simulation results.

Reconstruction of lower face defect or deformity with submental artery perforator flaps.

PubMed

Shi, Cheng-li; Wang, Xian-cheng

2012-07-01

Reconstruction of lower face defects or deformity often presents as a challenge for plastic surgeons. Many methods, including skin graft, tissue expander, or free flap are introduced. Submental artery perforator flaps have been used in the reconstruction of defects or deformities of the lower face. Between August 2006 and December 2008, 22 patients with lower face defects or deformity underwent reconstruction with pedicled submental artery perforator flaps. Their age ranged between 14 and 36 years. The perforator arteries were detected and labeled with a hand-held Doppler flowmeter. The size of flaps ranged from 4 × 6 to 6 × 7 cm, and the designed flaps included the perforator artery. All the flaps survived well, except 1 flap which resulted in partial necrosis in distal region and healed after conservative therapy. No other complication occurred with satisfactory aesthetic appearance of the donor site. The submental artery perforator flap is a thin and reliable flap with robust blood supply. This flap can reduce donor-site morbidity significantly and is a good choice for reconstructive surgery of lower face.

Analysis of deformation patterns through advanced DINSAR techniques in Istanbul megacity

NASA Astrophysics Data System (ADS)

Balik Sanli, F.; Calò, F.; Abdikan, S.; Pepe, A.; Gorum, T.

2014-09-01

As result of the Turkey's economic growth and heavy migration processes from rural areas, Istanbul has experienced a high urbanization rate, with severe impacts on the environment in terms of natural resources pressure, land-cover changes and uncontrolled sprawl. As a consequence, the city became extremely vulnerable to natural and man-made hazards, inducing ground deformation phenomena that threaten buildings and infrastructures and often cause significant socio-economic losses. Therefore, the detection and monitoring of such deformation patterns is of primary importance for hazard and risk assessment as well as for the design and implementation of effective mitigation strategies. Aim of this work is to analyze the spatial distribution and temporal evolution of deformations affecting the Istanbul metropolitan area, by exploiting advanced Differential SAR Interferometry (DInSAR) techniques. In particular, we apply the Small BAseline Subset (SBAS) approach to a dataset of 43 TerraSAR-X images acquired, between November 2010 and June 2012, along descending orbits with an 11-day revisit time and a 3 m × 3 m spatial resolution. The SBAS processing allowed us to remotely detect and monitor subsidence patterns over all the urban area as well as to provide detailed information at the scale of the single building. Such SBAS measurements, effectively integrated with ground-based monitoring data and thematic maps, allows to explore the relationship between the detected deformation phenomena and urbanization, contributing to improve the urban planning and management.

Crustal structure and tectonic deformation of the southern Ecuadorian margin

NASA Astrophysics Data System (ADS)

Calahorrano, Alcinoe; Collot, Jean-Yves; Sage, Françoise; Ranero, César R.

2010-05-01

Multichannel seismic lines acquired during the SISTEUR cruise (2000) provide new constraints on the structure and deformation of the subduction zone at the southern Ecuadorian margin, from the deformation front to the continental shelf of the Gulf of Guayaquil. The pre-stack depth migrated images allows to characterise the main structures of the downgoing and overriding plates and to map the margin stratigraphy in order to propose a chronology of the deformation, by means of integrating commercial well data and industry seismic lines located in the gulf area. The 100-km-long seismic lines show the oceanic Nazca plate underthrusting the South American plate, as well as the subduction channel and inter-plate contact from the deformation front to about 90 km landward and ~20 km depth. Based on seismic structure we identify four upper-plate units, consisting of basement and overlaying sedimentary sequences A, B and C. The sedimentary cover varies along the margin, being few hundreds of meters thick in the lower and middle slope, and ~2-3 km thick in the upper slope. Exceptionally, a ~10-km -thick basin, here named Banco Peru basin, is located on the upper slope at the southernmost part of the gulf. This basin seems to be the first evidence of the Gulf of Guayaquil opening resulting from the NE escaping of the North Andean Block. Below the continental shelf, thick sedimentary basins of ~6 to 8 km occupy most of the gulf area. Tectonic deformation across most of the upper-plate is dominated by extensional regime, locally disturbed by diapirism. Compression evidences are restricted to the deformation front and surrounding areas. Well data calibrating the seismic profiles indicate that an important portion of the total thickness of the sedimentary coverage of the overriding plate are Miocene or older. The data indicate the extensional deformation resulting from the NE motion of the North Andean Block and the opening of the Gulf of Guayaquil, evolves progressively in age

Acquired pendular nystagmus

PubMed Central

Kang, Sarah; Shaikh, Aasef G.

2017-01-01

Acquired pendular nystagmus is comprised of quasi-sinusoidal oscillations of the eyes significantly affecting gaze holding and clarity of vision. The most common causes of acquired pendular nystagmus include demyelinating disorders such as multiple sclerosis and the syndrome of ocular palatal tremor. However, several other deficits, such as pharmacological intoxication, metabolic and genetic disorders, and granulomatous disorders can lead to syndromes mimicking acquired pendular nystagmus. Study of the kinematic features of acquired pendular nystagmus has suggested a putative pathophysiology of an otherwise mysterious neurological disorder. Here we review clinical features of neurological deficits that co-occur with acquired pendular nystagmus. Subsequent discussion of the pathophysiology of individual forms of pendular nystagmus speculates on mechanisms of the underlying disease while providing insights into pharmacotherapy of nystagmus. PMID:28320194

Deformation measurement for a rotating deformable lap based on inverse fringe projection

NASA Astrophysics Data System (ADS)

Liao, Min; Zhang, Qican

2015-03-01

The active deformable lap (also namely stressed lap) is an efficient polishing tool in optical manufacturing. To measure the dynamic deformation caused by outside force on a deformable lap is important and helpful to the opticians to ensure the performance of a deformable lap as expected. In this paper, a manual deformable lap was designed to simulate the dynamic deformation of an active stressed lap, and a measurement system was developed based on inverse projected fringe technique to restore the 3D shape. A redesigned inverse fringe has been projected onto the surface of the measured lap, and the deformations of the tested lap become much obvious and can be easily and quickly evaluated by Fourier fringe analysis. Compared with the conventional projection, this technique is more obvious, and it should be a promising one in the deformation measurement of the active stressed lap in optical manufacturing.

SU-F-J-81: Evaluation of Automated Deformable Registration Between Planning Computed Tomography (CT) and Daily Cone Beam CT Images Over the Course of Prostate Cancer Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matney, J; Hammers, J; Kaidar-Person, O

2016-06-15

Purpose: To compute daily dose delivered during radiotherapy, deformable registration needs to be relatively fast, automated, and accurate. The aim of this study was to evaluate the performance of commercial deformable registration software for deforming between two modalities: planning computed tomography (pCT) images acquired for treatment planning and cone beam (CB) CT images acquired prior to each fraction of prostate cancer radiotherapy. Methods: A workflow was designed using MIM Software™ that aligned and deformed pCT into daily CBCT images in two steps: (1) rigid shifts applied after daily CBCT imaging to align patient anatomy to the pCT and (2) normalizedmore » intensity-based deformable registration to account for interfractional anatomical variations. The physician-approved CTV and organ and risk (OAR) contours were deformed from the pCT to daily CBCT over the course of treatment. The same structures were delineated on each daily CBCT by a radiation oncologist. Dice similarity coefficient (DSC) mean and standard deviations were calculated to quantify the deformable registration quality for prostate, bladder, rectum and femoral heads. Results: To date, contour comparisons have been analyzed for 31 daily fractions of 2 of 10 of the cohort. Interim analysis shows that right and left femoral head contours demonstrate the highest agreement (DSC: 0.96±0.02) with physician contours. Additionally, deformed bladder (DSC: 0.81±0.09) and prostate (DSC: 0.80±0.07) have good agreement with physician-defined daily contours. Rectum contours have the highest variations (DSC: 0.66±0.10) between the deformed and physician-defined contours on daily CBCT imaging. Conclusion: For structures with relatively high contrast boundaries on CBCT, the MIM automated deformable registration provided accurate representations of the daily contours during treatment delivery. These findings will permit subsequent investigations to automate daily dose computation from CBCT. However

Differences in microbiological profile between community-acquired, healthcare-associated and hospital-acquired infections.

PubMed

Cardoso, Teresa; Ribeiro, Orquídea; Aragão, Irene; Costa-Pereira, Altamiro; Sarmento, António

2013-01-01

Microbiological profiles were analysed and compared for intra-abdominal, urinary, respiratory and bloodstream infections according to place of acquisition: community-acquired, with a separate analysis of healthcare-associated, and hospital-acquired. Prospective cohort study performed at a university tertiary care hospital over 1 year. Inclusion criteria were meeting the Centers for Disease Control definition of intra-abdominal, urinary, respiratory and bloodstream infections. A total of 1035 patients were included in the study. More than 25% of intra-abdominal infections were polymicrobial; multi-drug resistant gram-negatives were 38% in community-acquired, 50% in healthcare-associated and 57% in hospital-acquired. E. coli was the most prevalent among urinary infections: 69% in community-acquired, 56% in healthcare-associated and 26% in hospital-acquired; ESBL producers' pathogens were 10% in healthcare-associated and 3% in community-acquired and hospital-acquired. In respiratory infections Streptococcus pneumoniae was the most prevalent in community-acquired (54%) and MRSA in healthcare-associated (24%) and hospital-acquired (24%). A significant association was found between MRSA respiratory infection and hospitalization in the previous year (adjusted OR = 6.3), previous instrumentation (adjusted OR = 4.3) and previous antibiotic therapy (adjusted OR = 5.7); no cases were documented among patients without risk factors. Hospital mortality rate was 10% in community-acquired, 14% in healthcare-associated and 19% in hospital-acquired infection. This study shows that healthcare-associated has a different microbiologic profile than those from community or hospital acquired for the four main focus of infection. Knowledge of this fact is important because the existing guidelines for community-acquired are not entirely applicable for this group of patients.

Change in Stiffness of Pavement Layers in the Linear Discontinuous Deformation Area

NASA Astrophysics Data System (ADS)

Grygierek, Marcin

2017-10-01

The underground mining exploitation causes deformations on the surface of the area which are classified as continuous or discontinuous. Mining deformations cause loosening or compression of the subsoil. Loosening has an impact on the reduction of the subsoil stiffness. As a result the reduction of subsoil stiffness causes loosening of construction layers built in that subsoil. Pavement is a specific case. If there happens to be loosening then the fatigue life of pavement is reduced and premature damages can be observed such as fatigue cracks or/and structural deformation. Discontinuous deformations are an especially interesting case. They not only cause the reduction of the stiffness of the subsoil and pavement layers but also cause rapid deterioration in roughness. Change of roughness is very dangerous especially on fast roads such as a highway. Lately there can be observed the so called linear discontinuous surface deformations in the lanes in the mining area. Unfortunately, the ‘in situ’ research, presenting experiments on the effect of linear discontinuous deformations on the pavement, is in short supply. It is especially crucial with regard to the design of pavement reinforcement and the specification of optimal length of the reinforced part of the road. The article presents the results of ‘in situ’ tests carried out on the chosen pavements where the so called linear discontinuous surface deformation has appeared. The genesis of the damage is connected with the underground mining exploitation. Falling Weight Deflectometer (FWD) has been used in researches. Measuring points were carried out with high frequency which helped to acquire a very interesting distribution of deflections. The distribution of deflections well shows the impact of linear discontinuous deformation on the changes in stiffness pavement layers. In the analysis of data from FWD there has been used back calculation which worked modulus of layers out. The results of researches and

Outcome and safety analysis of 3D printed patient specific pedicle screw jigs for complex spinal deformities: A comparative study.

PubMed

Garg, Bhavuk; Gupta, Manish; Singh, Menaka; Kalyanasundaram, Dinesh

2018-05-03

Spinal deformities are very challenging to treat and have a great risk of neurological complications due to hardware placement during corrective surgery. Various techniques have been introduced to ensure safe and accurate placement of pedicle screws. Patient-specific screw guides with pre-drawn and pre-validated trajectory seems to be an attractive option. We have focused on developing 3D printing technique for complex spinal deformities in India. This study also aimed to compare the placement of pedicle screw with 3D printing and free hand technique. This is a retrospective comparative clinical study at an academic institutional setting. A total of 20 patients were enrolled during the study, 10 were operated with the help of 3D printing (group 1) and 10 were operated with freehand technique (group 2). Group 1 included 6 congenital, 3 adolescent idiopathic scoliosis (AIS), one post tubercular kyphosis and Group 2 included 5 congenital, 4 AIS and one post tubercular kyphosis patient. Primary outcomes were measured in terms of screw violation and secondary outcome were measured in terms of Surgical time, Blood loss, Radiation exposure (no. of shoots required) and complications. MIMICS v18.0 Software was used for 3D reconstruction from CT scan images of all the patients. 3-Matic software was used to create drill guide. 3-D printer from Stratasys Mojo ABS P 430 model material cartilage (a thermoplastic material) was used for printing of vertebrae model and jigs. Two sample test of proportion was used to compare correctly and wrongly pedicle screw placement with 3D printing and freehand technique. T-test with equal variance was used for operating surgical time and blood loss. This work was carried out by collaboration of Orthopaedics Department, All India Institute of Medical Sciences (AIIMS), New Delhi and Biomedical Engineering Department, Indian Institute of Technology (IIT) Delhi. This project received the grant of USD 60000 from Department of Biotechnology (DBT

Spatial variation in incidence of mouthpart deformities in larval chironomids (Diptera) from western Lake Erie

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hudson, L.A.; Ciborowski, J.J.H.; Corkum, L.D.

1995-12-31

The major source of contaminants to the sediments of the western basin of Lake Erie is the Detroit River. In order to determine if contaminant levels are reflected in incidences of genotoxicity of benthic invertebrates, the authors examined larvae of chironomids for mouthpart (mentum) deformities. Sediment genotoxicity is indicated when incidence of deformities in susceptible genera exceeds 5%. Samples were collected from three locations along the contaminant gradient extending from the Detroit River along the main shipping channel of the western basin. A composite sample was taken from several central locations in the western basin. Chironomids were hand-picked from ponarmore » grab or box core samples. The heads were mounted, identified to genus and examined for mentum deformities (extra or missing teeth). Chironomus dominated all samples. The incidence of deformities ({+-}SE) in Chironomus was greatest in the Trenton Channel of the Detroit River (7.8 {+-} 2.2%, n = 153), declined to 5.2 {+-} 1.4% (n = 233) in the center of the basin and was the lowest off East Sister Island (1.9 {+-} 0.9%, n = 210). The incidence of deformities was 4.4 {+-} 0.8% (n = 610) at a reference site on the Canadian side of the Detroit River (Crystal Bay). The spatial pattern of chironomid mentum deformities suggests that sediment genotoxicity declines from west to east in western Lake Erie.« less

The ANACONDA algorithm for deformable image registration in radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weistrand, Ola; Svensson, Stina, E-mail: stina.svensson@raysearchlabs.com

2015-01-15

Purpose: The purpose of this work was to describe a versatile algorithm for deformable image registration with applications in radiotherapy and to validate it on thoracic 4DCT data as well as CT/cone beam CT (CBCT) data. Methods: ANAtomically CONstrained Deformation Algorithm (ANACONDA) combines image information (i.e., intensities) with anatomical information as provided by contoured image sets. The registration problem is formulated as a nonlinear optimization problem and solved with an in-house developed solver, tailored to this problem. The objective function, which is minimized during optimization, is a linear combination of four nonlinear terms: 1. image similarity term; 2. grid regularizationmore » term, which aims at keeping the deformed image grid smooth and invertible; 3. a shape based regularization term which works to keep the deformation anatomically reasonable when regions of interest are present in the reference image; and 4. a penalty term which is added to the optimization problem when controlling structures are used, aimed at deforming the selected structure in the reference image to the corresponding structure in the target image. Results: To validate ANACONDA, the authors have used 16 publically available thoracic 4DCT data sets for which target registration errors from several algorithms have been reported in the literature. On average for the 16 data sets, the target registration error is 1.17 ± 0.87 mm, Dice similarity coefficient is 0.98 for the two lungs, and image similarity, measured by the correlation coefficient, is 0.95. The authors have also validated ANACONDA using two pelvic cases and one head and neck case with planning CT and daily acquired CBCT. Each image has been contoured by a physician (radiation oncologist) or experienced radiation therapist. The results are an improvement with respect to rigid registration. However, for the head and neck case, the sample set is too small to show statistical significance. Conclusions

Stability of surface plastic flow in large strain deformation of metals

NASA Astrophysics Data System (ADS)

Viswanathan, Koushik; Udapa, Anirduh; Sagapuram, Dinakar; Mann, James; Chandrasekar, Srinivasan

We examine large-strain unconstrained simple shear deformation in metals using a model two-dimensional cutting system and high-speed in situ imaging. The nature of the deformation mode is shown to be a function of the initial microstructure state of the metal and the deformation geometry. For annealed metals, which exhibit large ductility and strain hardening capacity, the commonly assumed laminar flow mode is inherently unstable. Instead, the imposed shear is accommodated by a highly rotational flow-sinuous flow-with vortex-like components and large-amplitude folding on the mesoscale. Sinuous flow is triggered by a plastic instability on the material surface ahead of the primary region of shear. On the other hand, when the material is extensively strain-hardened prior to shear, laminar flow again becomes unstable giving way to shear banding. The existence of these flow modes is established by stability analysis of laminar flow. The role of the initial microstructure state in determining the change in stability from laminar to sinuous / shear-banded flows in metals is elucidated. The implications for cutting, forming and wear processes for metals, and to surface plasticity phenomena such as mechanochemical Rehbinder effects are discussed.

Gaze-contingent soft tissue deformation tracking for minimally invasive robotic surgery.

PubMed

Mylonas, George P; Stoyanov, Danail; Deligianni, Fani; Darzi, Ara; Yang, Guang-Zhong

2005-01-01

The introduction of surgical robots in Minimally Invasive Surgery (MIS) has allowed enhanced manual dexterity through the use of microprocessor controlled mechanical wrists. Although fully autonomous robots are attractive, both ethical and legal barriers can prohibit their practical use in surgery. The purpose of this paper is to demonstrate that it is possible to use real-time binocular eye tracking for empowering robots with human vision by using knowledge acquired in situ. By utilizing the close relationship between the horizontal disparity and the depth perception varying with the viewing distance, it is possible to use ocular vergence for recovering 3D motion and deformation of the soft tissue during MIS procedures. Both phantom and in vivo experiments were carried out to assess the potential frequency limit of the system and its intrinsic depth recovery accuracy. The potential applications of the technique include motion stabilization and intra-operative planning in the presence of large tissue deformation.

Deformation and kinematics of the central Kirthar Fold Belt, Pakistan

NASA Astrophysics Data System (ADS)

Hinsch, Ralph; Hagedorn, Peter; Asmar, Chloé; Nasim, Muhammad; Aamir Rasheed, Muhammad; Kiely, James M.

2017-04-01

The Kirthar Fold Belt is part of the lateral mountain belts in Pakistan linking the Himalaya orogeny with the Makran accretionary wedge. This region is deforming very oblique/nearly parallel to the regional plate motion vector. The study area is situated between the prominent Chaman strike-slip fault in the West and the un-deformed foreland (Kirthar Foredeep/Middle Indus Basin) in the East. The Kirthar Fold Belt is subdivided into several crustal blocks/units based on structural orientation and deformation style (e.g. Kallat, Khuzdar, frontal Kirthar). This study uses newly acquired and depth-migrated 2D seismic lines, surface geology observations and Google Earth assessments to construct three balanced cross sections for the frontal part of the fold belt. Further work was done in order to insure the coherency of the built cross-sections by taking a closer look at the regional context inferred from published data, simple analogue modelling, and constructed regional sketch sections. The Khuzdar area and the frontal Kirthar Fold Belt are dominated by folding. Large thrusts with major stratigraphic repetitions are not observed. Furthermore, strike-slip faults in the Khuzdar area are scarce and not observed in the frontal Kirthar Fold Belt. The regional structural elevation rises from the foreland across the Kirthar Fold Belt towards the hinterland (Khuzdar area). These observations indicate that basement-involved deformation is present at depth. The domination of folding indicates a weak decollement below the folds (soft-linked deformation). The fold pattern in the Khuzdar area is complex, whereas the large folds of the central Kirthar Fold Belt trend SSW-NNE to N-S and are best described as large detachment folds that have been slightly uplifted by basement involved transpressive deformation underneath. Towards the foreland, the deformation is apparently more hard-linked and involves fault-propagation folding and a small triangle zone in Cretaceous sediments

Deformation twinning in a creep-deformed nanolaminate structure

NASA Astrophysics Data System (ADS)

Hsiung, Luke L.

2010-10-01

The underlying mechanism of deformation twinning occurring in a TiAl-(γ)/Ti3Al-(α2) nanolaminate creep deformed at elevated temperatures has been studied. Since the multiplication and propagation of lattice dislocations in both γ and α2 thin lamellae are very limited, the total flow of lattice dislocations becomes insufficient to accommodate the accumulated creep strains. Consequently, the movement of interfacial dislocations along the laminate interfaces, i.e., interface sliding, becomes an alternative deformation mode of the nanolaminate structure. Pile-ups of interfacial dislocations occur when interfacial ledges and impinged lattice dislocations act as obstacles to impede the movement of interfacial dislocations. Deformation twinning can accordingly take place to relieve a stress concentration resulting from the pile-up of interfacial dislocations. An interface-controlled twinning mechanism driven by the pile-up and dissociation of interfacial dislocations is accordingly proposed.

Acquired pendular nystagmus.

PubMed

Kang, Sarah; Shaikh, Aasef G

2017-04-15

Acquired pendular nystagmus is comprised of quasi-sinusoidal oscillations of the eyes significantly affecting gaze holding and clarity of vision. The most common causes of acquired pendular nystagmus include demyelinating disorders such as multiple sclerosis and the syndrome of ocular palatal tremor. However, several other deficits, such as pharmacological intoxication, metabolic and genetic disorders, and granulomatous disorders can lead to syndromes mimicking acquired pendular nystagmus. Study of the kinematic features of acquired pendular nystagmus has suggested a putative pathophysiology of an otherwise mysterious neurological disorder. Here we review clinical features of neurological deficits that co-occur with acquired pendular nystagmus. Subsequent discussion of the pathophysiology of individual forms of pendular nystagmus speculates on mechanisms of the underlying disease while providing insights into pharmacotherapy of nystagmus. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of automated monitoring and real-time prompting on nurses' hand hygiene performance.

PubMed

Levchenko, Alexander I; Boscart, Veronique M; Fernie, Geoff R

2013-10-01

Adequate hand hygiene compliance by healthcare staff is considered an effective method to reduce hospital-acquired infections. The electronic system developed at Toronto Rehabilitation Institute automatically detects hand hygiene opportunities and records hand hygiene actions. It includes an optional visual hand hygiene status indication, generates real-time hand hygiene prompting signals, and enables automated monitoring of individual and aggregated hand hygiene performance. The system was installed on a complex continuous care unit at the entrance to 17 patient rooms and a utility room. A total of 93 alcohol gel and soap dispensers were instrumented and 14 nurses were provided with the personal wearable electronic monitors. The study included three phases with the system operating in three different modes: (1) an inactive mode during the first phase when hand hygiene opportunities and hand hygiene actions were recorded but prompting and visual indication functions were disabled, (2) only hand hygiene status indicators were enabled during the second phase, and (3) both hand hygiene status and real-time hand hygiene prompting signals were enabled during the third phase. Data collection was performed automatically during all of the three phases. The system indicated significantly higher hand hygiene activity rates and compliance during the third phase, with both hand hygiene indication and real-time prompting functions enabled. To increase the efficacy of the technology, its use was supplemented with individual performance reviews of the automatically collected data.

Synthetic Aperture Radar Interferometry Analysis of Ground Deformation within the Coso Geothermal Site, California

NASA Astrophysics Data System (ADS)

Brawner, Erik

Earth's surface movement may cause as a potential hazard to infrastructure and people. Associated earthquake hazards pose a potential side effect of geothermal activity. Modern remote sensing techniques known as Interferometric Synthetic Aperture Radar (InSAR) can measure surface change with a high degree of precision to mm scale movements. Previous work has identified a deformation anomaly within the Coso Geothermal site in eastern California. Surface changes have not been analyzed since the 1990s, allowing a decade of geothermal production impact to occur since previously assessed. In this study, InSAR data was acquired and analyzed between the years 2005 and 2010. Acquired by the ENVISAT satellite from both ascending and descending modes. This provides an independent dataset from previous work. Incorporating data generated from a new sensor covering a more modern temporal study period. Analysis of this time period revealed a subsidence anomaly in correlation with the extents of the geothermal production area under current operation. Maximum subsidence rates in the region reached approximately 3.8 cm/yr. A similar rate assessed from previous work throughout the 1990s. The correlation of subsidence patterns suggests a linear source of deformation from measurements spanning multiple decades. Regions of subsidence branch out from the main anomaly to the North-Northeast and to the South where additional significant peaks of subsidence occurring. The extents of the deformation anomaly directly correlate with the dispersal of geothermal production well site locations. Depressurization within the geothermal system provides a leading cause to surface subsidence from excessive extraction of hydrothermal fluids. As a result of minimal reinjection of production fluids.

Heterotic flux tubes in N=2 supersymmetric QCD with N=1 preserving deformations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shifman, M.; Yung, A.; Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300

2008-06-15

We consider non-Abelian Bogomol'nyi-Prasad-Sommerfield-saturated flux tubes (strings) in N=2 supersymmetric QCD deformed by superpotential terms of a special type breaking N=2 supersymmetry down to N=1. Previously it was believed that world sheet supersymmetry is accidentally enhanced due to the facts that N=(1,1) supersymmetry is automatically elevated up to N=(2,2) on CP(N-1) and, at the same time, there are no N=(0,2) generalizations of the bosonic CP(N-1) model. Edalati and Tong noted that the target space is in fact CP(N-1)xC rather than CP(N-1). This allowed them to suggest a heterotic N=(0,2) sigma model, with the CP(N-1) target space for bosonic fields andmore » an extra right-handed fermion which couples to the fermion fields of the N=(2,2) CP(N-1) model. We derive the heterotic N=(0,2) world sheet model directly from the bulk theory. The relation between the bulk and world sheet deformation parameters we obtain does not coincide with that suggested by Edalati and Tong at large values of the deformation parameter. For polynomial deformation superpotentials in the bulk we find nonpolynomial response in the world sheet model. We find a geometric representation for the heterotic model. Supersymmetry is proven to be spontaneously broken for small deformations (at the quantum level). This confirms Tong's conjecture. A proof valid for large deformations will be presented in the subsequent publication.« less

The role of simultaneous gap arthroplasty and distraction osteogenesis in the management of temporo-mandibular joint ankylosis with mandibular deformity in children.

PubMed

Rao, Krishna; Kumar, Sudhir; Kumar, Vijay; Singh, Arun Kumar; Bhatnagar, Sudhir Kumar

2004-02-01

Temporo-mandibular joint ankylosis is a common cause of acquired deformity in children. Surgical correction of the ankylosis only leaves the patient with an uncorrected mandibular deformity. This study was to evaluate the use of distraction osteogenesis for simultaneous correction of the mandibular deformity. This study was done on six children with temporo-mandibular joint ankylosis and mandibular deformity. Uniaxial double pin distractors with Schanz pins were used in this study. The patients underwent simultaneous gap arthroplasty and mandibular osteotomy (retromolar) with distractor insertion. Distraction was started on the fifth post-operative day. The patients were put on dynamic temporo-mandibular joint exercises on the first post-operative day. All patients had a satisfactory mouth opening on follow-up. Satisfactory cosmetic correction of the mandibular deformity was also achieved in all these patients. Some degree of malocclusion resulted from treatment due to which the patients were placed on orthodontic treatment. Distraction osteogenesis can be used simultaneously with gap arthroplasty in patients with temporo-mandibular ankylosis, for the correction of the mandibular deformity.

InSAR Maps of Deformation Covering Raft River, Idaho from 2007 to 2010

DOE Data Explorer

Reinisch, Elena C. (ORCID:0000000252211921)

2007-03-11

This dataset contains maps of deformation covering Raft River, Idaho from 2007 to 2010 calculated from interferometric synthetic aperture radar data. This dataset is used in the study entitled "Inferring geothermal reservoir processes at the Raft River Geothermal Field, Idaho, USA through modeling InSAR-measured surface deformation" by F. Liu, et al. This dataset was derived from raw SAR data from the Envisat satellite missions operated by the European Space Agency (ESA) that are copyrighted by ESA and were provided through the WInSAR consortium at the UNAVCO facility. All pair directories use the image acquired on 3/11/2007 as a reference image. To view specific information for each grd file, please use the GMT command "grdinfo" - e.g., for grd file In20070311_20071111/drho_utm.grd, use terminal command: grdinfo In20070311_20071111/drho_utm.grd

Reconstruction of acquired sub-total ear defects with autologous costal cartilage.

PubMed

Harris, P A; Ladhani, K; Das-Gupta, R; Gault, D T

1999-06-01

Acquired sub-total ear defects are common and challenging to reconstruct. We report the use of an autologous costal cartilage framework to reconstruct sub-total defects involving all anatomical regions of the ear. Twenty-eight partially damaged ears in 27 patients were reconstructed with this technique. The defects resulted from bites (14), road traffic accidents (five), burns (four), iatrogenic causes (four) and chondritis following minor trauma (one). Computerised image analysis revealed a median of 31% (range 13-72%) ear loss. An autologous costal cartilage framework was fashioned in all cases. If adequate local skin was available, this was draped over the framework, but in nine cases preliminary tissue expansion was used and in a further three cases with significant scarring, the framework was covered with a temporoparietal fascial flap. Clinical assessment after ear reconstruction was undertaken, scoring for symmetry, the helical rim, the antihelical fold, the lobe position and a 'natural look' to produce a four-point scale; 11 were excellent, 12 were good, two were fair and three were poor. Our experience suggests that formal delayed reconstruction with autologous costal cartilage is to be recommended when managing acquired, sub-total ear deformity.

The properties of Q-deformed hyperbolic and trigonometric functions in quantum deformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deta, U. A., E-mail: utamaalan@yahoo.co.id, E-mail: utamadeta@unesa.ac.id; Suparmi

2015-09-30

Quantum deformation has been studied due to its relation with applications in nuclear physics, conformal field theory, and statistical-quantum theory. The q-deformation of hyperbolic function was introduced by Arai. The application of q-deformed functions has been widely used in quantum mechanics. The properties of this two kinds of system explained in this paper including their derivative. The graph of q-deformed functions presented using Matlab. The special case is given for modified Poschl-Teller plus q-deformed Scarf II trigonometry potentials.

Postseismic Deformation: Different mechanisms in different times and places.

NASA Astrophysics Data System (ADS)

Segall, P.

2004-12-01

Improved understanding of postseismic deformation may elucidate time dependent stress transfer and triggered seismicity following large earthquakes. Afterslip, distributed viscoelastic flow, and poroelastic relaxation alter crustal stress and pore pressure distributions and in many cases lead to distinctive surface deformation patterns. Delayed triggering, due to rate and state dependent friction, on the other hand need not lead to detectable surface deformation. Postseismic deformation recorded following the 1999 ChiChi, Taiwan, 2003 Tokachi-Oki, Japan, and 2000 south Iceland earthquakes can be used to test for the effects of these processes. Horizontal displacements of 10 cm accumulated in the first year following the Chi-Chi quake. These are best explained with continued slip on the Chelungpu fault (Hsu et al, G.R.L. 2002). Inversions indicate the afterslip was roughly localized in a ring around the locus of maximum coseismic slip. The observed displacement pattern is inconsistent with predictions from viscoelastic and poroelastic models. Viscoelastic relaxation of the lower crust produces shortening of the hanging wall instead of the observed extension. The fully drained poroelastic response predicts deformation concentrated near the fault ends, which was not observed. Fully time dependent calculations, however, are still required because poroelastic displacements need not be monotonic. Afterslip following the M 8 Tokachi Oki earthquake is also localized around the area of high mainshock slip (Miyazaki et al, GRL, 2004). Surprisingly, the slip is not located downdip of the mainshock, but along strike of the source region. This indicates that the transient deformation is not caused by deceleration of the earthquake instability, but rather by stress increases due to the mainshock. A major question is whether intermediate depth afterslip following the Tokachi Oki and ChiChi earthquakes occurs in stable (steady state velocity strengthening) areas which will never

Using environmental engineering to increase hand hygiene compliance: a cross-over study protocol.

PubMed

Schmidtke, Kelly Ann; Aujla, Navneet; Marshall, Tom; Hussain, Abid; Hodgkinson, Gerard P; Arheart, Kristopher; Marti, Joachim; Birnbach, David J; Vlaev, Ivo

2017-09-11

Compliance with hand hygiene recommendations in hospital is typically less than 50%. Such low compliance inevitably contributes to hospital-acquired infections that negatively affect patients' well-being and hospitals' finances. The design of the present study is predicated on the assumption that most people who fail to clean their hands are not doing so intentionally, they just forget. The present study will test whether psychological priming can be used to increase the number of people who clean their hands on entering a ward. Here, we present the protocol for this study. The study will use a randomised cross-over design. During the study, each of four wards will be observed during four conditions: olfactory prime, visual prime, both primes and neither prime. Each condition will be experienced for 42 days followed by a 7-day washout period (total duration of trial=189 days). We will record the number of people who enter each ward and whether they clean their hands during observation sessions, the amount of cleaning material used from the dispensers each week and the number of hospital-acquired infections that occur in each period. The outcomes will be compared using a regression analysis. Following the initial trail, the most effective priming condition will be rolled out for 3 months in all the wards. Research ethics approval was obtained from the South Central-Oxford C Research Ethics Committee (16/SC/0554), the Health Regulatory Authority and the sponsor. ISRCTN (15397624); Edge ID 86357. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Treatment of severe radial club hand by distraction using an articulated mini-rail fixator and transfixing pins.

PubMed

Romana, C; Ciais, G; Fitoussi, F

2015-06-01

Treatment of severe radial club hand is difficult. Several authors have emphasized the importance of preliminary soft-tissue distraction before centralization. Treatment of severe radial club hand by articulated mini-rail allowing prior soft-tissue distraction improves results. Thirteen patients were treated sequentially, with an initial step of distraction and a second step of centralization. The first step consisted in fitting 2 mini-fixators, one in the concavity and the other in the convexity of the deformity. Four transfixing wires through the ulna and metacarpal bone connected the 2 fixators. After this preliminary distraction, the fixator was removed and a centralization wire was introduced percutaneously, with ulnar osteotomy if necessary. Sagittal and coronal correction was measured on the angle between forearm and hand. Mean age at treatment was 37.5 months (range, 9-120 months). Mean distraction time was 53.2 days (26-90 days). Ulnar osteotomy was required in 8 cases (61%). There were no major complications requiring interruption of distraction. Sagittal and coronal correction after centralization reduced mean residual forearm/hand angulation to<12°. Soft-tissue distraction in the concavity ahead of centralization is essential to good correction, avoiding extensive soft-tissue release and hyperpressure on the distal ulnar growth plate. There have been several studies of distraction; the present technique, associating 2 mini-fixators connected by threaded K-wires, provided sufficient distraction in the concavity of the deformity to allow satisfactory correction in all cases. Subsequent complications (breakage or displacement of the centralization wires) testify to the complexity of long-term management. The present study confirms the interest of a preliminary soft-tissue distraction step in treating severe radial club hand. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Near-Surface Geophysical Imaging of Deformation Associated with the Daytona Beach Sand Blow Deposits, Lee County, Arkansas

NASA Astrophysics Data System (ADS)

Rohrer, M.; Harris, J. B.; Cearley, C.; Teague, M.

2017-12-01

Within the past decade or so, paleoseismologic and geophysical studies at the Daytona Beach (DB) site in east-central Arkansas have reported earthquake-induced liquefaction (sand blows) along a prominent NW-trending lineament dated to approximately 5.5 ka. A recent compressional-wave (P-wave) seismic reflection survey acquired by the U. S. Geological Survey (USGS) along Highway 243 in Lee County, Arkansas, across the DB sand blow cluster, identified a previously unknown fault zone that is likely associated with the liquefaction. However, the USGS data were not able to image the Quaternary section (<60 m deep) and show a direct connection between the deeper faulting and the sand blows. In order to investigate the near-surface structure of the fault zone, we acquired an integrated geophysical data set consisting of 430-m-long shear-wave (S-wave) seismic reflection and ground penetrating radar (GPR) profiles above the deformation imaged on the USGS profile. The S-wave reflection data were collected using a 24-channel, towable landstreamer and the seismic energy was generated by a sledgehammer/I-beam source. The GPR data were collected with a cart-mounted 250-MHz system, using a 0.5-m antenna spacing and a 0.10-m step size. The processed seismic profile exhibits coherent reflection energy throughout the Quaternary section. Changes in reflection amplitude and coherency, offset reflections, and abundant diffractions suggest the presence of a complex zone of high-angle faults in the shallow subsurface coincident with the mapped lineament. Folded shallow reflections show that the deformation extends upward to within 10 m of the surface. Furthermore, the GPR profile images a distinct zone of deformation in the very near surface (<1.5 m deep) that is coincident with the upward projection of the deformation imaged on the S-wave seismic reflection profile.

Surface Deformation and Coherence Measurements of Kilauea Volcano, Hawaii, from SIR-C Radar Interferometry

NASA Technical Reports Server (NTRS)

Rosen, P. A.; Hensley, S.; Zebker, H. A.; Webb, F. H.; Fielding, E. J.

1996-01-01

The shuttle imaging radar C/X synthetic aperture radar (SIR-C/X-SAR) radar on board the space shuttle Endeavor imaged Kilauea Volcano, Hawaii, in April and October 1994 for the purpose of measuring active surface deformation by the methods of repeat-pass differential radar interferometry. Observations at 24 cm (L band) and 5.6 cm (C band) wavelengths were reduced to interferograms showing apparent surface deformation over the 6-month interval and over a succession of 1-day intervals in October. A statistically significant local phase signature in the 6-month interferogram is coincident with the Pu'u O'o lava vent. Interpreted as deformation, the signal implies centimeter-scale deflation in an area several kilometers wide surrounding the vent. Peak deflation is roughly 14 cm if the deformation is purely vertical, centered southward of the Pu'u O'o caldera. Delays in the radar signal phase induced by atmospheric refractivity anomalies introduce spurious apparent deformation signatures, at the level of 12 cm peak-to-peak in the radar line-of-sight direction. Though the phase observations are suggestive of the wide-area deformation measured by Global Positioning System (GPS) methods, the atmospheric effects are large enough to limit the interpretation of the result. It is difficult to characterize centimeter-scale deformations spatially distributed over tens of kilometers using differential interferometry without supporting simultaneous, spatially distributed measurements of reactivity along the radar line of sight. Studies of the interferometric correlation of images acquired at different times show that L band is far superior to C band in the vegetated areas, even when the observations are separated by only 1 day. These results imply longer wavelength instruments are more appropriate for studying surfaces by repeat-pass observations.

Automatic segmentation of bones from digital hand radiographs

NASA Astrophysics Data System (ADS)

Liu, Brent J.; Taira, Ricky K.; Shim, Hyeonjoon; Keaton, Patricia

1995-05-01

The purpose of this paper is to develop a robust and accurate method that automatically segments phalangeal and epiphyseal bones from digital pediatric hand radiographs exhibiting various stages of growth. The algorithm uses an object-oriented approach comprising several stages beginning with the most general objects to be segmented, such as the outline of the hand from background, and proceeding in a succession of stages to the most specific object, such as a specific phalangeal bone from a digit of the hand. Each stage carries custom operators unique to the needs of that specific stage which will aid in more accurate results. The method is further aided by a knowledge base where all model contours and other information such as age, race, and sex, are stored. Shape models, 1-D wrist profiles, as well as an interpretation tree are used to map model and data contour segments. Shape analysis is performed using an arc-length orientation transform. The method is tested on close to 340 phalangeal and epiphyseal objects to be segmented from 17 cases of pediatric hand images obtained from our clinical PACS. Patient age ranges from 2 - 16 years. A pediatric radiologist preliminarily assessed the results of the object contours and were found to be accurate to within 95% for cases with non-fused bones and to within 85% for cases with fused bones. With accurate and robust results, the method can be applied toward areas such as the determination of bone age, the development of a normal hand atlas, and the characterization of many congenital and acquired growth diseases. Furthermore, this method's architecture can be applied to other image segmentation problems.

17 CFR 210.8-06 - Real estate operations acquired or to be acquired.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 17 Commodity and Securities Exchanges 2 2012-04-01 2012-04-01 false Real estate operations acquired or to be acquired. 210.8-06 Section 210.8-06 Commodity and Securities Exchanges SECURITIES AND...-06 Real estate operations acquired or to be acquired. If, during the period for which income...

17 CFR 210.8-06 - Real estate operations acquired or to be acquired.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 17 Commodity and Securities Exchanges 2 2013-04-01 2013-04-01 false Real estate operations acquired or to be acquired. 210.8-06 Section 210.8-06 Commodity and Securities Exchanges SECURITIES AND...-06 Real estate operations acquired or to be acquired. If, during the period for which income...

17 CFR 210.8-06 - Real estate operations acquired or to be acquired.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 17 Commodity and Securities Exchanges 3 2014-04-01 2014-04-01 false Real estate operations acquired or to be acquired. 210.8-06 Section 210.8-06 Commodity and Securities Exchanges SECURITIES AND...-06 Real estate operations acquired or to be acquired. If, during the period for which income...

Mentor's hand hygiene practices influence student's hand hygiene rates.

PubMed

Snow, Michelle; White, George L; Alder, Stephen C; Stanford, Joseph B

2006-02-01

There were 3 objectives for this prospective quasiexperimental study. The first was to determine the effect of mentor's hand hygiene practices on student's hand hygiene rates during clinical rotations. The second was to assess the difference in hand hygiene rates for students with and without prior medical experience. The third was to assess the student's opinion and beliefs regarding hand hygiene. Sixty students enrolled in a certified nursing program were selected to participate in the study. Each study group was observed twice during the 30-day span. The first observational period was conducted on day 1 of clinical rotation. The second observational period was conducted on day 30 of clinical rotation. Students were observed for hand hygiene. Also assessed were medical experience, sex, gloving, age, and mentor's hand hygiene practices. After observational period 2, a brief questionnaire was given to students to determine their opinion and beliefs regarding hand hygiene. The questionnaire was divided into 5 sections: student's commitment to hand hygiene, their perception of hand hygiene inconvenience, the necessity of hand hygiene, the student's ability to perform hand hygiene, and their opinion on the frequency of medical staff's hand hygiene. The mentor's practice of hand hygiene was the strongest predictor of the student's rate of hand hygiene for both observational periods (P < .01). Furthermore, students without prior medical experience had a significant increase in hand hygiene rates when comparing observational period 1 to observational period 2 (P < .01). Glove usage was associated with increased hand hygiene rates by 50% during observational period 1 (P = .01) and 44% during observational period 2 (P < .01). Male students during observational period 1 practiced hand hygiene 30% less often than female students (P < .01); however, during observational period 2, there was no significant difference between hand hygiene rates for males and females (P = .82

Effect of initial grain size on inhomogeneous plastic deformation and twinning behavior in high manganese austenitic steel with a polycrystalline microstructure

NASA Astrophysics Data System (ADS)

Ueji, R.; Tsuchida, N.; Harada, K.; Takaki, K.; Fujii, H.

2015-08-01

The grain size effect on the deformation twinning in a high manganese austenitic steel which is so-called TWIP (twining induced plastic deformation) steel was studied in order to understand how to control deformation twinning. The 31wt%Mn-3%Al-3% Si steel was cold rolled and annealed at various temperatures to obtain fully recrystallized structures with different mean grain sizes. These annealed sheets were examined by room temperature tensile tests at a strain rate of 10-4/s. The coarse grained sample (grain size: 49.6μm) showed many deformation twins and the deformation twinning was preferentially found in the grains in which the tensile axis is parallel near to [111]. On the other hand, the sample with finer grains (1.8 μm) had few grains with twinning even after the tensile deformation. The electron back scattering diffraction (EB SD) measurements clarified the relationship between the anisotropy of deformation twinning and that of inhomogeneous plastic deformation. Based on the EBSD analysis, the mechanism of the suppression of deformation twinning by grain refinement was discussed with the concept of the slip pattern competition between the slip system governed by a grain boundary and that activated by the macroscopic load.

Models of determining deformations

NASA Astrophysics Data System (ADS)

Gladilin, V. N.

2016-12-01

In recent years, a lot of functions designed to determine deformation values that occur mostly as a result of settlement of structures and industrial equipment. Some authors suggest such advanced mathematical functions approximating deformations as general methods for the determination of deformations. The article describes models of deformations as physical processes. When comparing static, cinematic and dynamic models, it was found that the dynamic model reflects the deformation of structures and industrial equipment most reliably.

Deformation of angle profiles in forward kinematics for nullifying end-point offset while preserving movement properties.

PubMed

Zhang, Xudong

2002-10-01

This work describes a new approach that allows an angle-domain human movement model to generate, via forward kinematics, Cartesian-space human movement representation with otherwise inevitable end-point offset nullified but much of the kinematic authenticity retained. The approach incorporates a rectification procedure that determines the minimum postural angle change at the final frame to correct the end-point offset, and a deformation procedure that deforms the angle profile accordingly to preserve maximum original kinematic authenticity. Two alternative deformation schemes, named amplitude-proportional (AP) and time-proportional (TP) schemes, are proposed and formulated. As an illustration and empirical evaluation, the proposed approach, along with two deformation schemes, was applied to a set of target-directed right-hand reaching movements that had been previously measured and modeled. The evaluation showed that both deformation schemes nullified the final frame end-point offset and significantly reduced time-averaged position errors for the end-point as well as the most distal intermediate joint while causing essentially no change in the remaining joints. A comparison between the two schemes based on time-averaged joint and end-point position errors indicated that overall the TP scheme outperformed the AP scheme. In addition, no statistically significant difference in time-averaged angle error was identified between the raw prediction and either of the deformation schemes, nor between the two schemes themselves, suggesting minimal angle-domain distortion incurred by the deformation.

Motion Control of Drives for Prosthetic Hand Using Continuous Myoelectric Signals

NASA Astrophysics Data System (ADS)

Purushothaman, Geethanjali; Ray, Kalyan Kumar

2016-03-01

In this paper the authors present motion control of a prosthetic hand, through continuous myoelectric signal acquisition, classification and actuation of the prosthetic drive. A four channel continuous electromyogram (EMG) signal also known as myoelectric signals (MES) are acquired from the abled-body to classify the six unique movements of hand and wrist, viz, hand open (HO), hand close (HC), wrist flexion (WF), wrist extension (WE), ulnar deviation (UD) and radial deviation (RD). The classification technique involves in extracting the features/pattern through statistical time domain (TD) parameter/autoregressive coefficients (AR), which are reduced using principal component analysis (PCA). The reduced statistical TD features and or AR coefficients are used to classify the signal patterns through k nearest neighbour (kNN) as well as neural network (NN) classifier and the performance of the classifiers are compared. Performance comparison of the above two classifiers clearly shows that kNN classifier in identifying the hidden intended motion in the myoelectric signals is better than that of NN classifier. Once the classifier identifies the intended motion, the signal is amplified to actuate the three low power DC motor to perform the above mentioned movements.

Hand hygiene technique quality evaluation in nursing and medicine students of two academic courses 1

PubMed Central

Škodová, Manuela; Gimeno-Benítez, Alfredo; Martínez-Redondo, Elena; Morán-Cortés, Juan Francisco; Jiménez-Romano, Ramona; Gimeno-Ortiz, Alfredo

2015-01-01

Abstract Objective: because they are health professionals, nursing and medical students' hands during internships can function as a transmission vehicle for hospital-acquired infections. Method: a descriptive study with nursing and medical degree students on the quality of the hand hygiene technique, which was assessed via a visual test using a hydroalcoholic solution marked with fluorescence and an ultraviolet lamp. Results: 546 students were assessed, 73.8% from medicine and 26.2% from nursing. The area of the hand with a proper antiseptic distribution was the palm (92.9%); areas not properly scrubbed were the thumbs (55.1%). 24.7% was very good in both hands, 29.8% was good, 25.1% was fair, and 20.3% was poor. The worst assessed were the male, nursing and first year students. There were no significant differences in the age groups. Conclusions: hand hygiene technique is not applied efficiently. Education plays a key role in setting a good practice base in hand hygiene, theoretical knowledge, and in skill development, as well as good practice reinforcement. PMID:26444174

17 CFR 210.8-06 - Real estate operations acquired or to be acquired.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 17 Commodity and Securities Exchanges 2 2011-04-01 2011-04-01 false Real estate operations acquired or to be acquired. 210.8-06 Section 210.8-06 Commodity and Securities Exchanges SECURITIES AND... Statements of Smaller Reporting Companies § 210.8-06 Real estate operations acquired or to be acquired. If...

Back to basics: hand hygiene and surgical hand antisepsis.

PubMed

Spruce, Lisa

2013-11-01

Health care-associated infections (HAIs) are a significant issue in the United States and throughout the world, but following proper hand hygiene practices is the most effective and least expensive way to prevent HAIs. Hand hygiene is inexpensive and protects patients and health care personnel alike. The four general types of hand hygiene that should be performed in the perioperative environment are washing hands that are visibly soiled, hand hygiene using alcohol-based products, surgical hand scrubs, and surgical hand scrubs using an alcohol-based surgical hand rub product. Barriers to proper hand hygiene may include not thinking about it, forgetting, skin irritation, a lack of role models, or a lack of a safety culture. One strategy for improving hand hygiene practices is monitoring hand hygiene as part of a quality improvement project, but the most important aspect for perioperative team members is to set an example for other team members by following proper hand hygiene practices and reminding each other to perform hand hygiene. Copyright © 2013 AORN, Inc. Published by Elsevier Inc. All rights reserved.

Microtia Combined With Split Sole of Feet, Deformed Middle Fingers and Café -au-lait Spots on the Trunk: A New Association.

PubMed

Yu, Yan; Hu, Jintian; Liu, Tun; Cao, Yilin; Zhang, Qingguo

2015-11-01

Microtia is a spectrum of congenital deformities. Approximately, half of the patients are associated with hemifacial microtia. The birth rate of microtia ranges from 2 per 10,000 to 17.4 per 10,000. Microtia and limb deformities sometimes occurred simultaneously as described in the literature. In this report, the patient was found to be with unilateral microtia combined with bilateral split sole of feet, deformed middle fingers on both hands, and café-au-lait spots on the trunk. Despite a thorough literature search, the authors could not achieve a satisfactory diagnosis for the current case with respect to the type of anomalies seen in the case.

Mechanism for Angular Deformation of L-shaped Specimens —Influence of Filling Material and Shrinkage Factor—

NASA Astrophysics Data System (ADS)

Furuhashi, Hiroshi; Aoki, Takerou; Okabe, Sayaka; Arai, Tsuyoshi; Seto, Masahiro; Yamabe, Masashi

L-shape is the important and fundamental shape for injection molded parts. Therefore to reveal the corner angular deformation mechanism of this shape is also valuable for understanding the warpage mechanism of injection molded parts. In this study, we investigated the influence of the filling materials (fiber, talc and not filled) and two kinds of anisotropic shrinkage factors, solidification shrinkage and shrinkage caused by thermal expansion coefficient during cooling, to the angular deformation of L-shaped specimens and the following conclusions were obtained 1) The anisotropic solidification shrinkage of MD/TD and the anisotropic thermal expansion coefficient of MD/TD are considered to cause the angular deformation of L-shaped specimens. But the contribution ratios of these two anisotropies depend on the filling material for plastics. 2) The angular deformation of PP and PBT filled with glass fiber is mainly caused by the anisotropic thermal expansion coefficient and on the other hand, that of PP and PBT without filling material is caused by anisotropic solidification shrinkage. However both anisotropies cause the angular deformation of PP filled with talc. 3) The plate thickness dependence of the angular deformation of PP filled with talc is the singular peculiar phenomenon. The plate thickness dependence of anisotropic solidification shrinkage of this material (it is also singular) is considered to have an important influence on this phenomenon.

Whole-field macro- and micro-deformation characteristic of unbound water-loss in dentin hard tissue.

PubMed

Chen, Zhenning; Nadeau, Bobby; Yu, Kevin; Shao, Xinxing; He, Xiaoyuan; Goh, M Cynthia; Kishen, Anil

2018-04-06

High-resolution deformation measurements in a functionally graded hard tissue such as human dentin are essential to understand the unbound water-loss mediated changes and their role in its mechanical integrity. Yet a whole-field, 3-dimensional (3D) measurement and characterization of fully hydrated dentin in both macro- and micro-scales remain to be a challenge. This study was conducted in 2 stages. In stage-1, a stereo-digital image correlation approach was utilized to determine the water-loss and load-induced 3D deformations of teeth in a sagittal section over consecutively acquired frames, from a fully hydrated state to nonhydrated conditions for a period up to 2 hours. The macroscale analysis revealed concentrated residual deformations at the dentin-enamel-junction and the apical regions of root in the direction perpendicular to the dentinal tubules. Significant difference in the localized deformation characteristics was observed between the inner and outer aspects of the root dentin. During quasi-static loadings, further increase in the residual deformation was observed in the dentin. In stage-2, dentin microstructural variations induced by dynamic water-loss were assessed with environmental scanning electron microscopy and atomic force microscopy (AFM), showing that the dynamic water-loss induced distention of dentinal tubules with concave tubular edges, and concurrent contraction of intertubular dentin with convex profile. The findings from the current macro- and micro-scale analysis provided insight on the free-water-loss induced regional deformations and ultrastructural changes in human dentin. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Medical and surgical treatments of congenital and acquired penile curvatures: a review].

PubMed

Guillot-Tantay, C; Phé, V; Chartier-Kastler, E; Mozer, P; Bitker, M-O; Rouprêt, M

2014-03-01

The aim of the current study was to provide an overview about the surgical and medical management of acquired and congenital penile's curvature. [corrected] A systematic review of the literature was done from the PubMed database by searching the following keywords alone or in combination: Congenital penile curvature; Congenital penile deviation; Acquired penile curvature; Acquired penile deviation; Peyronie's disease. The treatment of congenital curvature is only surgical. The most common technique is the Nesbit's technique which consists in making elliptical excisions of the tunica albuginea. There are also incison or plication procedures which are efficient as well. Acquired curvature is most of the time represented by the Peyronie's disease or is post-traumatic. Among oral treatments available, the Potaba is the only drug which has proved a significant reduction in penile plaque size. Injections of interferon and nicardipine have also shown their efficacy. Ionotophoresis and extracorporeal shock-wave therapy may be beneficial for penile pain. Other therapies (vacuum, traction devices, topical Verapamil) can be interesting but other studies are necessary to recommend them. Surgical treatment is recommended during the fibrotic phase. The most common technique is also the Nesbit's technique. In case of severe curvature (curve superior to 60°), small penis, major deformations, graft techniques can be used. Moreover, if there is a sexual dysfunction, penile prosthesis is recommended. Other studies are necessary to prove the efficacy of most of the drugs already available in the treatment of the penile curvature. It seems to be interesting to combine the different treatments to improve the results of those therapies. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

[Bertha Röntgen or the transparency of the hand].

PubMed

Picard, J D

1996-01-01

It is to Wilhelm Conrad Röntgen, the first elected "radiologist" of our Academy and the first Nobel Prize winner in physics, that we owe the transparency of the hand. We celebrate today the centenary of the great scientific discovery which was to revolutionize the diagnosis, and thereby the treatment, of a large number of illnesses the discovery of X-rays. It would be unjust not to link the name of this scientist with that of his wife, Bertha, who, ignorant of the dangers of all "novel medical inventions" volunteered her own hand for his research experiments: the hand which was to bring to the world tangible proof of this remarkable discovery. To a lesser degree, but nonetheless essential, we acknowledge, albeit not in exhaustive detail, all the progress made by the work of pioneers using this new investigative technique. So let us now return to the hand:--a body part which it was easy to immobilize, remembering that in those days a single radiographic exposure took up to an hour to obtain,--we will consider the immortalised hand of Bertha Röntgen,---to whom this address is dedicated,---and its radiographic exposures which allow us to appreciate the advances and to perceive the limitations of this technique. They also enable us better to envisage future investigative approaches whereby a deeper knowledge of the human body may be acquired. We note that compared with the histopathological sciences, imaging is not specific. Numerous microscopic structures, in particular neurological and vascular ones, are still insufficiently well visualised and the transmission pathways between the hand and the central nervous system deserve better characterisation. Current, research programmes are attempting to overcome these limitation of modern imaging. All the experience gained in studying the transparency of the hand, as we have discussed, is applicable to every part of the human anatomy. To credit: Röntgen's discovery with all its originality, we could say that the hand was

A New CT Reconstruction Technique Using Adaptive Deformation Recovery and Intensity Correction (ADRIC)

PubMed Central

Zhang, You; Ma, Jianhua; Iyengar, Puneeth; Zhong, Yuncheng; Wang, Jing

2017-01-01

Purpose Sequential same-patient CT images may involve deformation-induced and non-deformation-induced voxel intensity changes. An adaptive deformation recovery and intensity correction (ADRIC) technique was developed to improve the CT reconstruction accuracy, and to separate deformation from non-deformation-induced voxel intensity changes between sequential CT images. Materials and Methods ADRIC views the new CT volume as a deformation of a prior high-quality CT volume, but with additional non-deformation-induced voxel intensity changes. ADRIC first applies the 2D-3D deformation technique to recover the deformation field between the prior CT volume and the new, to-be-reconstructed CT volume. Using the deformation-recovered new CT volume, ADRIC further corrects the non-deformation-induced voxel intensity changes with an updated algebraic reconstruction technique (‘ART-dTV’). The resulting intensity-corrected new CT volume is subsequently fed back into the 2D-3D deformation process to further correct the residual deformation errors, which forms an iterative loop. By ADRIC, the deformation field and the non-deformation voxel intensity corrections are optimized separately and alternately to reconstruct the final CT. CT myocardial perfusion imaging scenarios were employed to evaluate the efficacy of ADRIC, using both simulated data of the extended-cardiac-torso (XCAT) digital phantom and experimentally acquired porcine data. The reconstruction accuracy of the ADRIC technique was compared to the technique using ART-dTV alone, and to the technique using 2D-3D deformation alone. The relative error metric and the universal quality index metric are calculated between the images for quantitative analysis. The relative error is defined as the square root of the sum of squared voxel intensity differences between the reconstructed volume and the ‘ground-truth’ volume, normalized by the square root of the sum of squared ‘ground-truth’ voxel intensities. In addition to

Bacteriological Aspects of Hand Washing: A Key for Health Promotion and Infections Control

PubMed Central

Ataee, Ramezan Ali; Ataee, Mohammad Hosein; Mehrabi Tavana, Ali; Salesi, Mahmud

2017-01-01

The aim of this review is to show the historical aspects of hands washing for healthy life and explains how can reduce the transmission of community-acquired infectious agents by healthcare workers and patients. This review article is prepared based on available database. The key words used were hands washing, risk assessment, hands hygiene, bacterial flora, contamination, infection, nosocomial, tap water, sanitizer, bacterial resistance, hands bacterial flora, washing methods, antiseptics, healthcare workers, healthcare personnel, from PubMed, ScienceDirect, Embase, Scopus, Web of Sciences, and Google Scholar. Data were descriptively analyzed. The insistence on hand washing has a history of 1400 years. The research results indicate that the bacteria released from the female washed hands in wet and dry condition was lower than from the male's hands with a significance level (3 CFU vs. 8 CFU; confidence interval 95%, P ≤ 0.001). The valuable results of the study indicated that released amount of bacterial flora from wet hands is more than 10 times in compared to dry hands. In addition, established monitoring systems for washing hands before and after patient's manipulation as well as after toilet were dominant indices to prevent the transfer of infectious agents to the patients. Increasing awareness and belief of the healthcare workers have shown an important role by about 30% reduction in the transfection. Hand washing could reduce the episodes of transmission of infectious agents in both community and healthcare settings. However, hand washing is an important key factor to prevent transmission of infectious agents to patients. There is no standard method for measuring compliance. Thus, permanent monitoring of hand washing to reduce the transmission of infections is crucial. Finally, the personnel must believe that hand washing is an inevitable approach to infection control. PMID:28382192

Deformation of the Augustine Volcano, Alaska, 1992-2005, measured by ERS and ENVISAT SAR interferometry

USGS Publications Warehouse

Lee, Chang-Wook; Lu, Zhong; Kwoun, Oh-Ig; Won, Joong-Sun

2008-01-01

The Augustine Volcano is a conical-shaped, active stratovolcano located on an island of the same name in Cook Inlet, about 290 km southwest of Anchorage, Alaska. Augustine has experienced seven significant explosive eruptions - in 1812, 1883, 1908, 1935, 1963, 1976, 1986, and in January 2006. To measure the ground surface deformation of the Augustine Volcano before the 2006 eruption, we applied satellite radar interferometry using Synthetic Aperture Radar (SAR) images from three descending and three ascending satellite tracks acquired by European Remote Sensing Satellite (ERS) 1 and 2 and the Environment Satellite (ENVISAT). Multiple interferograms were stacked to reduce artifacts caused by atmospheric conditions, and we used a singular value decomposition method to retrieve the temporal deformation history from several points on the island. Interferograms during 1992 and 2005 show a subsidence of about 1-3 cm/year, caused by the contraction of pyroclastic flow deposits from the 1986 eruption. Subsidence has decreased exponentially with time. Multiple interferograms between 1992 and 2005 show no significant inflation around the volcano before the 2006 eruption. The lack of a pre-eruption deformation signal suggests that the deformation signal from 1992 to August 2005 must have been very small and may have been obscured by atmospheric delay artifacts. 

A scale space based algorithm for automated segmentation of single shot tagged MRI of shearing deformation.

PubMed

Sprengers, Andre M J; Caan, Matthan W A; Moerman, Kevin M; Nederveen, Aart J; Lamerichs, Rolf M; Stoker, Jaap

2013-04-01

This study proposes a scale space based algorithm for automated segmentation of single-shot tagged images of modest SNR. Furthermore the algorithm was designed for analysis of discontinuous or shearing types of motion, i.e. segmentation of broken tag patterns. The proposed algorithm utilises non-linear scale space for automatic segmentation of single-shot tagged images. The algorithm's ability to automatically segment tagged shearing motion was evaluated in a numerical simulation and in vivo. A typical shearing deformation was simulated in a Shepp-Logan phantom allowing for quantitative evaluation of the algorithm's success rate as a function of both SNR and the amount of deformation. For a qualitative in vivo evaluation tagged images showing deformations in the calf muscles and eye movement in a healthy volunteer were acquired. Both the numerical simulation and the in vivo tagged data demonstrated the algorithm's ability for automated segmentation of single-shot tagged MR provided that SNR of the images is above 10 and the amount of deformation does not exceed the tag spacing. The latter constraint can be met by adjusting the tag delay or the tag spacing. The scale space based algorithm for automatic segmentation of single-shot tagged MR enables the application of tagged MR to complex (shearing) deformation and the processing of datasets with relatively low SNR.

Poor hospital infection control practice in hand hygiene, glove utilization, and usage of tourniquets.

PubMed

Sacar, Suzan; Turgut, Huseyin; Kaleli, Ilknur; Cevahir, Nural; Asan, Ali; Sacar, Mustafa; Tekin, Koray

2006-11-01

Hospital-acquired infection often occurs because of lapses in accepted standards of practice on the part of health care personnel. The aim of this study is to attract attention on poor hospital infection control practice in venepuncture and use of tourniquets and emphasize the importance of hand hygiene. Overall compliance with hygiene during usage of tourniquets and routine patient care before and after implementation of a hospital infection control measures was evaluated. According to the questionnaire, only 26.9% of respondents always washed their hands both before and after venepuncture. In the second step of the study, based on direct observation, hands were washed both before and after venepuncture on only 41 (45.1%) occasions. Failure to remove gloves after patient contact was observed on 23.1% occasions. Our survey reveals poor infection control practice in hand hygiene, glove utilization, and usage of tourniquets and the implementation of infection control measures produced a moderate improvement in compliance with them.

Correcting Gravitational Deformation at the Tianma Radio Telescope

NASA Astrophysics Data System (ADS)

Dong, Jian; Zhong, Weiye; Wang, Jinqing; Liu, Qinghui; Shen, Zhiqiang

2018-04-01

The primary reflector of the Tianma Radio Telescope (TMRT) distorts due to gravity, which dramatically reduces the aperture efficiency of high-frequency observations. A technique known as outof-focus holography (OOF) has been developed to measure gravitational deformation. However, the TMRT has a shaped dual-reflector optical system, so the OOF technique cannot be used directly. An extended OOF (e-OOF) technique that can be used for a shaped telescope is proposed. A new calculation method is developed to calculate the extra phase and illumination. A new measurement strategy is proposed that uses only one feed, reduces the length of the scan pattern, and allows the telescope to scan smoothly at low speed. At the TMRT, the time required for each measurement is under 20 min, the achieved accuracy is approximately 50 μm, and the repeatability is sufficient. We have acquired a model for the gravitational deformation of the TMRT. After applying the model, there is a 150%-400% improvement in the aperture efficiency at low and high elevations. The model flattens the gain curve between 15°-80° elevations with an aperture efficiency of approximately 52%. The final weighted root-mean-square error is approximately 270 μm. The e-OOF technique reduces the constraints on the telescopes.

Video model deformation system for the National Transonic Facility

NASA Technical Reports Server (NTRS)

Burner, A. W.; Snow, W. L.; Goad, W. K.

1983-01-01

A photogrammetric closed circuit television system to measure model deformation at the National Transonic Facility is described. The photogrammetric approach was chosen because of its inherent rapid data recording of the entire object field. Video cameras are used to acquire data instead of film cameras due to the inaccessibility of cameras which must be housed within the cryogenic, high pressure plenum of this facility. A rudimentary theory section is followed by a description of the video-based system and control measures required to protect cameras from the hostile environment. Preliminary results obtained with the same camera placement as planned for NTF are presented and plans for facility testing with a specially designed test wing are discussed.

Monitoring Ground Deformation at the Aquistore CO2 Storage Site in SE Saskatchewan, Canada

NASA Astrophysics Data System (ADS)

Samsonov, S. V.; White, D.; Craymer, M. R.; Murnaghan, K.; Chalaturnyk, R. J.

2012-12-01

The scientific objectives of the Aquistore CO2 storage project is to design, adapt, and test non-seismic monitoring methods that have not been systematically utilized to date for monitoring CO2 storage, and to integrate the data from these various monitoring tools to obtain quantitative estimates of the change in subsurface fluid distributions, pressure changes and associated surface deformation. For this an array of monitoring methodologies will be tested, including satellite-, surface- and wellbore-based monitoring systems. Interferometric Synthetic Aperture Radar (InSAR), GPS and tiltmeter monitoring will be used for measuring any ground deformation caused by CO2 injection and the associated subsurface pressure perturbation. In the spring-summer of 2012 we started collecting C-band SAR data from the Canadian Radarsat-2 satellite to provide baseline data over the study site. The Radarsat-2 data is acquired about every six days on average in five different geometries in order to achieve nearly uninterrupted coverage. We acquire ascending and descending spotlight data with sub-meter resolution (1.6x0.8 m), ascending and descending wide ultra fine data with moderate resolution (1.6x2.8 m) and descending fine quad-pol data with coarse resolution (5.2x7.6 m). Over the project life, this SAR coverage will be supplemented by X-band TerraSAR-X data, C-band Sentinel, and L-band ALOS-2 data. Availability of SAR data from all three wave-band sensors should allow us to measure ground deformation with a precision of a few mm/year. For mitigating temporal de-correlation and for improving precision during the winter when there will be snow cover, we will install 13 paired corner reflectors suitable for ascending and descending imaging. Multidimensional time series of ground deformation will be produced using MSBAS techniques (Samsonov and d'Oreye, 2012). PolInSAR methodology will be tested on fine quad-pol data. To obtain higher precision spatial and higher resolution temporal

Hand preference and skilled hand performance among individuals with successful rightward conversions of the writing hand.

PubMed

Porac, Clare

2009-03-01

Searleman and Porac (2001) studied lateral preference patterns among successfully switched left-hand writers, left-hand writers with no switch pressure history, and left-hand writers who did not switch when pressured. They concluded that left-handers who successfully shift to right-hand writing are following an inherent right-sided lateralisation pattern that they already possess. Searleman and Porac suggested that the neural mechanisms that control lateralisation in the successfully switched individuals are systematically different from those of other groups of left-handers. I examined patterns of skilled and less-skilled hand preference and skilled hand performance in a sample of 394 adults (ages 18-94 years). The sample contained successfully switched left-hand writers, left-handers pressured to shift who remained left-hand writers, left-handers who did not experience shift pressures, and right-handers. Both skilled hand preference and skilled hand performance were shifted towards the right side in successfully switched left-hand writers. This group also displayed mixed patterns of hand preference and skilled hand performance in that they were not as right-sided as "natural" right-handers nor were they as left-sided as the two left-hand writing groups, which did not differ from each other. The experience of being pressured to switch to right-hand writing was not sufficient to shift lateralisation patterns; the pressures must be experienced in the context of an underlying neural control mechanism that is amenable to change as a result of these external influences.

Influence of action-effect associations acquired by ideomotor learning on imitation.

PubMed

Bunlon, Frédérique; Marshall, Peter J; Quandt, Lorna C; Bouquet, Cedric A

2015-01-01

According to the ideomotor theory, actions are represented in terms of their perceptual effects, offering a solution for the correspondence problem of imitation (how to translate the observed action into a corresponding motor output). This effect-based coding of action is assumed to be acquired through action-effect learning. Accordingly, performing an action leads to the integration of the perceptual codes of the action effects with the motor commands that brought them about. While ideomotor theory is invoked to account for imitation, the influence of action-effect learning on imitative behavior remains unexplored. In two experiments, imitative performance was measured in a reaction time task following a phase of action-effect acquisition. During action-effect acquisition, participants freely executed a finger movement (index or little finger lifting), and then observed a similar (compatible learning) or a different (incompatible learning) movement. In Experiment 1, finger movements of left and right hands were presented as action-effects during acquisition. In Experiment 2, only right-hand finger movements were presented during action-effect acquisition and in the imitation task the observed hands were oriented orthogonally to participants' hands in order to avoid spatial congruency effects. Experiments 1 and 2 showed that imitative performance was improved after compatible learning, compared to incompatible learning. In Experiment 2, although action-effect learning involved perception of finger movements of right hand only, imitative capabilities of right- and left-hand finger movements were equally affected. These results indicate that an observed movement stimulus processed as the effect of an action can later prime execution of that action, confirming the ideomotor approach to imitation. We further discuss these findings in relation to previous studies of action-effect learning and in the framework of current ideomotor approaches to imitation.

Influence of Action-Effect Associations Acquired by Ideomotor Learning on Imitation

PubMed Central

Bunlon, Frédérique; Marshall, Peter J.; Quandt, Lorna C.; Bouquet, Cedric A.

2015-01-01

According to the ideomotor theory, actions are represented in terms of their perceptual effects, offering a solution for the correspondence problem of imitation (how to translate the observed action into a corresponding motor output). This effect-based coding of action is assumed to be acquired through action-effect learning. Accordingly, performing an action leads to the integration of the perceptual codes of the action effects with the motor commands that brought them about. While ideomotor theory is invoked to account for imitation, the influence of action-effect learning on imitative behavior remains unexplored. In two experiments, imitative performance was measured in a reaction time task following a phase of action-effect acquisition. During action-effect acquisition, participants freely executed a finger movement (index or little finger lifting), and then observed a similar (compatible learning) or a different (incompatible learning) movement. In Experiment 1, finger movements of left and right hands were presented as action-effects during acquisition. In Experiment 2, only right-hand finger movements were presented during action-effect acquisition and in the imitation task the observed hands were oriented orthogonally to participants’ hands in order to avoid spatial congruency effects. Experiments 1 and 2 showed that imitative performance was improved after compatible learning, compared to incompatible learning. In Experiment 2, although action-effect learning involved perception of finger movements of right hand only, imitative capabilities of right- and left-hand finger movements were equally affected. These results indicate that an observed movement stimulus processed as the effect of an action can later prime execution of that action, confirming the ideomotor approach to imitation. We further discuss these findings in relation to previous studies of action-effect learning and in the framework of current ideomotor approaches to imitation. PMID:25793755

Volume and tissue composition preserving deformation of breast CT images to simulate breast compression in mammographic imaging

NASA Astrophysics Data System (ADS)

Han, Tao; Chen, Lingyun; Lai, Chao-Jen; Liu, Xinming; Shen, Youtao; Zhong, Yuncheng; Ge, Shuaiping; Yi, Ying; Wang, Tianpeng; Shaw, Chris C.

2009-02-01

Images of mastectomy breast specimens have been acquired with a bench top experimental Cone beam CT (CBCT) system. The resulting images have been segmented to model an uncompressed breast for simulation of various CBCT techniques. To further simulate conventional or tomosynthesis mammographic imaging for comparison with the CBCT technique, a deformation technique was developed to convert the CT data for an uncompressed breast to a compressed breast without altering the breast volume or regional breast density. With this technique, 3D breast deformation is separated into two 2D deformations in coronal and axial views. To preserve the total breast volume and regional tissue composition, each 2D deformation step was achieved by altering the square pixels into rectangular ones with the pixel areas unchanged and resampling with the original square pixels using bilinear interpolation. The compression was modeled by first stretching the breast in the superior-inferior direction in the coronal view. The image data were first deformed by distorting the voxels with a uniform distortion ratio. These deformed data were then deformed again using distortion ratios varying with the breast thickness and re-sampled. The deformation procedures were applied in the axial view to stretch the breast in the chest wall to nipple direction while shrinking it in the mediolateral to lateral direction re-sampled and converted into data for uniform cubic voxels. Threshold segmentation was applied to the final deformed image data to obtain the 3D compressed breast model. Our results show that the original segmented CBCT image data were successfully converted into those for a compressed breast with the same volume and regional density preserved. Using this compressed breast model, conventional and tomosynthesis mammograms were simulated for comparison with CBCT.

The role of twinning deformation on the hardening response of polycrystalline magnesium from discrete dislocation dynamics simulations

DOE PAGES

Fan, Haidong; Aubry, Sylvie; Arsenlis, Athanasios; ...

2015-04-13

The mechanical response of micro-twinned polycrystalline magnesium was studied through three-dimensional discrete dislocation dynamics (DDD). A systematic interaction model between dislocations and (1012) tension twin boundaries (TBs) was proposed and introduced into the DDD framework. In addition, a nominal grain boundary (GB) model agreeing with experimental results was also introduced to mimic the GB’s barrier effect. The current simulation results show that TBs act as a strong obstacle to gliding dislocations, which contributes significantly to the hardening behavior of magnesium. On the other hand, the deformation accommodated by twinning plays a softening role. Therefore, the concave shape of the Mgmore » stress-strain curve results from the competition between dislocation-TB induced hardening and twinning deformation induced softening. At low strain levels, twinning deformation induced softening dominates and a decreasing hardening rate is observed in Stage-I. In Stage-II, both the hardening and softening effects decline, but twinning deformation induced softening declines faster, which leads to an increasing hardening rate.« less

Image-based Modeling of PSF Deformation with Application to Limited Angle PET Data

PubMed Central

Matej, Samuel; Li, Yusheng; Panetta, Joseph; Karp, Joel S.; Surti, Suleman

2016-01-01

The point-spread-functions (PSFs) of reconstructed images can be deformed due to detector effects such as resolution blurring and parallax error, data acquisition geometry such as insufficient sampling or limited angular coverage in dual-panel PET systems, or reconstruction imperfections/simplifications. PSF deformation decreases quantitative accuracy and its spatial variation lowers consistency of lesion uptake measurement across the imaging field-of-view (FOV). This can be a significant problem with dual panel PET systems even when using TOF data and image reconstruction models of the detector and data acquisition process. To correct for the spatially variant reconstructed PSF distortions we propose to use an image-based resolution model (IRM) that includes such image PSF deformation effects. Originally the IRM was mostly used for approximating data resolution effects of standard PET systems with full angular coverage in a computationally efficient way, but recently it was also used to mitigate effects of simplified geometric projectors. Our work goes beyond this by including into the IRM reconstruction imperfections caused by combination of the limited angle, parallax errors, and any other (residual) deformation effects and testing it for challenging dual panel data with strongly asymmetric and variable PSF deformations. We applied and tested these concepts using simulated data based on our design for a dedicated breast imaging geometry (B-PET) consisting of dual-panel, time-of-flight (TOF) detectors. We compared two image-based resolution models; i) a simple spatially invariant approximation to PSF deformation, which captures only the general PSF shape through an elongated 3D Gaussian function, and ii) a spatially variant model using a Gaussian mixture model (GMM) to more accurately capture the asymmetric PSF shape in images reconstructed from data acquired with the B-PET scanner geometry. Results demonstrate that while both IRMs decrease the overall uptake

[Does the hand solely belong in the hands of a qualified hand surgeon?

PubMed

Güven, Asim; Kols, Kerstin; Fischer, Klaus; Schönberger, Michael; Allert, Sixtus

2017-09-01

Background In Germany, Hand Surgery is an additional qualification that can only be obtained by a three-year training after a completed residency in General Surgery, Plastic Surgery or Trauma and Orthopaedic Surgery. Nevertheless, injuries and diseases of the hand are also treated by physicians without this particular qualification. It is questionable whether these treatments more often lead to medical malpractice. Material and Methods 376 charges of medical malpractice in surgical treatments of the hand and forearm that were closed in 2014 and 2015 were collected by the Arbitration Board for Medical Liability Issues of the Medical Association of North Germany.Cases with proven medical malpractice were classified by the qualification of the physician in charge and analysed. A statistical analysis was performed with the use of the program SPSS (IBM). Results Medical malpractice was proven in 42 of 113 cases with an attending physician who held the additional qualification for Hand Surgery (37.2 %). For physicians without this qualification, the figures were 79 out of 155 (51.0 %) in the group of trauma and orthopaedic surgeons and 54 out of 108 (50.0 %) in the group of general surgeons. The differences between the hand surgeons and the trauma and orthopaedic surgeons (p = 0.017) and between hand surgeons and general surgeons were significant (p = 0.037). Conclusions It was shown that physicians with an additional qualification in hand surgery had signifcantly fewer proven medical malpratice cases than physicians without this qualification. The following trends were observed in the cases of the physicians without the additional qualification in hand surgery: underestimation of the severity of trauma to soft tissues and infections of the hand, errors in the surgical examination of the hand, including functional tests of tendons and nerves, as well as in diagnostic findings after X-ray studies of the hand. Georg Thieme Verlag KG Stuttgart · New York.

Technique of Dynamic Flexor Digitorum Superficialis Transfer to Lateral Bands for Proximal Interphalangeal Joint Deformity Correction in Severe Dupuytren Disease.

PubMed

Schreck, Michael J; Holbrook, Hayden S; Koman, L Andrew

2018-02-01

Pseudo-boutonniere deformity is an uncommon complication from long-standing proximal interphalangeal (PIP) joint contracture in Dupuytren disease. Prolonged flexion contracture of the PIP joint can lead to central slip attenuation and resultant imbalances in the extensor mechanism. We present a technique of flexor digitorum superficialis (FDS) tendon transfer to the lateral bands to correct pseudo-boutonniere deformity at the time of palmar fasciectomy for the treatment of Dupuytren disease. The FDS tendon is transferred from volar to dorsal through the lumbrical canal and sutured into the dorsally mobilized lateral bands. This technique presents an approach to the repair of pseudo-boutonniere deformity in Dupuytren disease. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Hands-on-Universe, Europe Bringing frontline interactive astronomy to the classroom

NASA Astrophysics Data System (ADS)

Ferlet, R.

Hands-on-Universe, Europe (EU-HOU) aims at re-awakening the interest for science in the young generations through astronomy and new technologies. It relies on real observations acquired through a worldwide internet-based network of automatic telescopes or with didactical tools (webcam, radiotelescope). Pupils manipulate images in the classroom environment, using specific software within pedagogical resources constructed in close collaboration between researchers and teachers. EU-HOU is freely available on the web, and trains european teachers.

Non-invasive imaging of zebrafish with spinal deformities using optical coherence tomography: a preliminary study

NASA Astrophysics Data System (ADS)

Bernstein, Liane; Beaudette, Kathy; Patten, Kessen; Beaulieu-Ouellet, Émilie; Strupler, Mathias; Moldovan, Florina; Boudoux, Caroline

2013-03-01

A zebrafish model has recently been introduced to study various genetic mutations that could lead to spinal deformities such as scoliosis. However, current imaging techniques make it difficult to perform longitudinal studies of this condition in zebrafish, especially in the early stages of development. The goal of this project is to determine whether optical coherence tomography (OCT) is a viable non-invasive method to image zebrafish exhibiting spinal deformities. Images of both live and fixed malformed zebrafish (5 to 21 days postfertilization) as well as wild-type fish (5 to 29 days postfertilization) were acquired non-invasively using a commercial SD-OCT system, with a laser source centered at 930nm (λ=100nm), permitting axial and lateral resolutions of 7 and 8μm respectively. Using two-dimensional images and three-dimensional reconstructions, it was possible to identify the malformed notochord as well as deformities in other major organs at different stages of formation. Visualization of the notochord was facilitated with the development of a segmentation algorithm. OCT images were compared to HE histological sections and images obtained by calcein staining. Because of the possibility of performing longitudinal studies on a same fish and reducing image processing time as compared with staining techniques and histology, the use of OCT could facilitate phenotypic characterization in studying genetic factors leading to spinal deformities in zebrafish and could eventually contribute to the identification of the genetic causes of spinal deformities such as scoliosis.

Computer aided segmentation of kidneys using locally shape constrained deformable models on CT images

NASA Astrophysics Data System (ADS)

Erdt, Marius; Sakas, Georgios

2010-03-01

This work presents a novel approach for model based segmentation of the kidney in images acquired by Computed Tomography (CT). The developed computer aided segmentation system is expected to support computer aided diagnosis and operation planning. We have developed a deformable model based approach based on local shape constraints that prevents the model from deforming into neighboring structures while allowing the global shape to adapt freely to the data. Those local constraints are derived from the anatomical structure of the kidney and the presence and appearance of neighboring organs. The adaptation process is guided by a rule-based deformation logic in order to improve the robustness of the segmentation in areas of diffuse organ boundaries. Our work flow consists of two steps: 1.) a user guided positioning and 2.) an automatic model adaptation using affine and free form deformation in order to robustly extract the kidney. In cases which show pronounced pathologies, the system also offers real time mesh editing tools for a quick refinement of the segmentation result. Evaluation results based on 30 clinical cases using CT data sets show an average dice correlation coefficient of 93% compared to the ground truth. The results are therefore in most cases comparable to manual delineation. Computation times of the automatic adaptation step are lower than 6 seconds which makes the proposed system suitable for an application in clinical practice.

Curiosity's Mars Hand Lens Imager (MAHLI): Inital Observations and Activities

NASA Technical Reports Server (NTRS)

Edgett, K. S.; Yingst, R. A.; Minitti, M. E.; Robinson, M. L.; Kennedy, M. R.; Lipkaman, L. J.; Jensen, E. H.; Anderson, R. C.; Bean, K. M.; Beegle, L. W.;

Analysis of Mining Terrain Deformation Characteristics with Deformation Information System

NASA Astrophysics Data System (ADS)

Blachowski, Jan; Milczarek, Wojciech; Grzempowski, Piotr

2014-05-01

Mapping and prediction of mining related deformations of the earth surface is an important measure for minimising threat to surface infrastructure, human population, the environment and safety of the mining operation itself arising from underground extraction of useful minerals. The number of methods and techniques used for monitoring and analysis of mining terrain deformations is wide and increasing with the development of geographical information technologies. These include for example: terrestrial geodetic measurements, global positioning systems, remote sensing, spatial interpolation, finite element method modelling, GIS based modelling, geological modelling, empirical modelling using the Knothe theory, artificial neural networks, fuzzy logic calculations and other. The aim of this paper is to introduce the concept of an integrated Deformation Information System (DIS) developed in geographic information systems environment for analysis and modelling of various spatial data related to mining activity and demonstrate its applications for mapping and visualising, as well as identifying possible mining terrain deformation areas with various spatial modelling methods. The DIS concept is based on connected modules that include: the spatial database - the core of the system, the spatial data collection module formed by: terrestrial, satellite and remote sensing measurements of the ground changes, the spatial data mining module for data discovery and extraction, the geological modelling module, the spatial data modeling module with data processing algorithms for spatio-temporal analysis and mapping of mining deformations and their characteristics (e.g. deformation parameters: tilt, curvature and horizontal strain), the multivariate spatial data classification module and the visualization module allowing two-dimensional interactive and static mapping and three-dimensional visualizations of mining ground characteristics. The Systems's functionality has been presented on

Contribution of Deformation to Sea Ice Mass Balance: A Case Study From an N-ICE2015 Storm

NASA Astrophysics Data System (ADS)

Itkin, Polona; Spreen, Gunnar; Hvidegaard, Sine Munk; Skourup, Henriette; Wilkinson, Jeremy; Gerland, Sebastian; Granskog, Mats A.

2018-01-01

The fastest and most efficient process of gaining sea ice volume is through the mechanical redistribution of mass as a consequence of deformation events. During the ice growth season divergent motion produces leads where new ice grows thermodynamically, while convergent motion fractures the ice and either piles the resultant ice blocks into ridges or rafts one floe under the other. Here we present an exceptionally detailed airborne data set from a 9 km2 area of first year and second year ice in the Transpolar Drift north of Svalbard that allowed us to estimate the redistribution of mass from an observed deformation event. To achieve this level of detail we analyzed changes in sea ice freeboard acquired from two airborne laser scanner surveys just before and right after a deformation event brought on by a passing low-pressure system. A linear regression model based on divergence during this storm can explain 64% of freeboard variability. Over the survey region we estimated that about 1.3% of level sea ice volume was pressed together into deformed ice and the new ice formed in leads in a week after the deformation event would increase the sea ice volume by 0.5%. As the region is impacted by about 15 storms each winter, a simple linear extrapolation would result in about 7% volume increase and 20% deformed ice fraction at the end of the season.

Systemic mistakes in hand hygiene practice in Ukraine: detection, consequences and ways of elimination

PubMed Central

Klymenko, Iryna; Kampf, Günter

2015-01-01

Aim: Every year, millions of people around the world suffer from different infectious diseases, considerable part of which are hospital-acquired infections. WHO considers hand hygiene as a priority measure aimed to reduce the level of infection. We evaluated various aspects related to the situational behavior and prioritization regarding hand hygiene measures among the healthcare workers of Ukraine. Method: Identification of system mistakes in hand hygiene was carried out first of all by direct and indirect observation of the activities of medical and pharmaceutical personnel in their everyday practice as well as during their participation in trainings on routine hand hygiene. Questionnaires also were used to estimate the level of hand hygiene compliance of participants of the study. During this period 112 training courses, 315 master-classes and presentations on proper hand hygiene were realized. The target audience included health care workers of medical centers, clinics, maternity hospitals, health care organizations and staff of pharmacies and pharmaceutical manufacturing enterprises in all regions of Ukraine. 638 respondents took part in anonymous survey on hand hygiene practice. Results: The most common mistakes were to regard hand washing and hand disinfection equally, to wash hands before doing a hand disinfection, to neglect the five moments for hand hygiene and to ignore hand hygiene before and after wearing protective gloves. Practitioners, medical attendants, pharmacy and pharmaceutical industry workers highlighted the need for practical and understandable instructions of various hand hygiene procedures, including the clarification of the possible technical mistakes. This became a ground for us to create individual master classes on hand hygiene for each cluster of healthcare workers. Conclusions: Changing hand hygiene behavior and attitude is possible by beginning to observe clinical practice and by involving healthcare workers in teaching and training

4D-CT motion estimation using deformable image registration and 5D respiratory motion modeling.

PubMed

Yang, Deshan; Lu, Wei; Low, Daniel A; Deasy, Joseph O; Hope, Andrew J; El Naqa, Issam

2008-10-01

Four-dimensional computed tomography (4D-CT) imaging technology has been developed for radiation therapy to provide tumor and organ images at the different breathing phases. In this work, a procedure is proposed for estimating and modeling the respiratory motion field from acquired 4D-CT imaging data and predicting tissue motion at the different breathing phases. The 4D-CT image data consist of series of multislice CT volume segments acquired in ciné mode. A modified optical flow deformable image registration algorithm is used to compute the image motion from the CT segments to a common full volume 3D-CT reference. This reference volume is reconstructed using the acquired 4D-CT data at the end-of-exhalation phase. The segments are optimally aligned to the reference volume according to a proposed a priori alignment procedure. The registration is applied using a multigrid approach and a feature-preserving image downsampling maxfilter to achieve better computational speed and higher registration accuracy. The registration accuracy is about 1.1 +/- 0.8 mm for the lung region according to our verification using manually selected landmarks and artificially deformed CT volumes. The estimated motion fields are fitted to two 5D (spatial 3D+tidal volume+airflow rate) motion models: forward model and inverse model. The forward model predicts tissue movements and the inverse model predicts CT density changes as a function of tidal volume and airflow rate. A leave-one-out procedure is used to validate these motion models. The estimated modeling prediction errors are about 0.3 mm for the forward model and 0.4 mm for the inverse model.

Ground deformation associated with the 2008 Sichuan Earthquake in China, estimated using a SAR offset-tracking method

NASA Astrophysics Data System (ADS)

Kobayashi, T.; Takada, Y.; Furuya, M.; Murakami, M.

2008-12-01

Introduction: A catastrophic earthquake struck China"fs Sichuan area on May 12, 2008, with the moment magnitude of 7.9 (USGS). The hypocenter and their aftershocks are distributed along the western edge of the Sichuan Basin, suggesting that this seismic event occurred at the Longmeng Shan fault zone which is constituted of major three active faults (Wenchuan-Maowen, Beichuan, and Pengguan faults). However, it is unclear whether these faults were directly involved in the mainshock rupture. An interferometry SAR (InSAR) analysis generally has a merit that we can detect ground deformation in a vast region with high precision, however, for the Sichuan event, the surface deformation near the fault zone has not been satisfactorily detected from the InSAR analyses due to a low coherency. An offset-tracking method is less precise but more robust for detecting large ground deformation than the interferometric approach. Our purpose is to detect the detail ground deformation immediately near the faults involved in the Sichuan event with applying the offset-tracking method. Analysis Method: We analyzed ALOS/PALSAR images, which have been taken from Path 471 to 476 of ascending track, acquired before and after the mainshock. We processed SAR data from the level-1.0 product, using a software package from Gamma Remote Sensing. For offset-tracking analysis we adopt intensity tracking method which is performed by cross-correlating samples of backscatter intensity of a master SAR image with samples from the corresponding search area of a slave image in order to estimate range and azimuth offset fields. We reduce stereoscopic effects that produce apparent offsets, using SRTM3 DEM data. Results: We have successfully obtained the surface deformation in range (radar look direction) component, while in azimuth (flight direction) no significant deformation can be detected in some orbits due to "gazimuth streaks"h that are errors caused by ionospheric effects. Some concluding remarks are

Cyclic Deformation of Ultra-Fine Grained Commercial Purity Aluminum Processed by Accumulative Roll-Bonding.

PubMed

Kwan, Charles C F; Wang, Zhirui

2013-08-13

Accumulative Roll-Bonding (ARB) is one of the more recently developed techniques capable of producing bulk ultra-fine grained (ufg) metals. There are still many aspects of the behavior of ufg metals that lacks an in-depth understanding, such as a generalized view of the factors that govern the cyclic deformation mechanism(s). This study aims to advance the understanding of the cyclic deformation behavior of ufg metals through the systematic investigation of ARB processed aluminum upon cyclic loading. It was found that the cyclic softening response often reported for ufg metals is largely influenced by the microstructure stability as the cyclic softening response is facilitated by grain coarsening which becomes inhibited with highly stable microstructure. On one hand, shear bands resembling braids of dislocations trespassing multiple grains have been observed to operate for the accommodation of the imposed cyclic strain in cases where grain coarsening is largely restricted. On the other hand, it was found that the microstructure stability can be overcome at higher applied cyclic plastic strain levels, leading to grain coarsening and thus a cyclic softening response. The findings in this study have further confirmed that the cyclic softening behavior found in many ufg metals, which may be detrimental in practical applications, can be inhibited by improvements in the microstructure stability.

Anti-bacterial efficacy of alcoholic hand rubs in the Kenyan market, 2015.

PubMed

Ochwoto, Missiani; Muita, Lucy; Talaam, Keith; Wanjala, Cecilia; Ogeto, Frank; Wachira, Faith; Osman, Saida; Kimotho, James; Ndegwa, Linus

2017-01-01

Hand hygiene is known to be effective in preventing hospital and community-acquired infections. The increasing number of hand sanitizer brands in Kenyan hospitals and consumer outlets is of concern. Thus the main aim of this study was to evaluate the anti-bacterial efficacy and organoleptic properties of these hand sanitizers in Kenya. This was an experimental, laboratory-based study of 14 different brands of hand sanitizers (coded HS1-14) available in various retail outlets and hospitals in Kenya. Efficacy was evaluated using standard non-pathogenic Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATCC 27853) as per the European Standard (EN). The logarithmic reduction factors (RF) were assessed at baseline and after treatment, and log reduction then calculated. Ten and 25 healthy volunteers participated in the efficacy and organoleptic studies respectively. Four (28.6%) hand sanitizers (HS12, HS9, HS13 and HS14) showed a 5.9 reduction factor on all the three bacteria strains. Seven (50%) hand sanitizers had efficacies of <3 against all the three bacteria strains used. Efficacy on E. Coli was higher compared to the other pathogens. Three hand sanitizers were efficacious on one of the pathogens and not the other. In terms of organoleptic properties, gel-based formulations were rated far higher than the liquid based formulations brands. Fifty percent (50%) of the selected hand sanitizers in the Kenyan market have efficacy that falls below the World Health Organization (WHO) and DIN EN 1500:2013. Of the 14 hand sanitizers found in the Kenyan market, only four showed efficacies that were comparable to the WHO-formulation. There is a need to evaluate how many of these products with <3 efficacy that have been incorporated into the health system for hand hygiene and the country's policy on regulations on their usage.

Classification for congenital anomalies of the hand: the IFSSH classification and the JSSH modification.

PubMed

De Smet, L

2002-01-01

The purpose of a classification for clinical problems which, except for a few specialized centers, occur only sporadically is to provide a system where these cases can be stored. This should allow all involved investigators to speak the same language; so-doing syndromes can be delinated, frequencies of occurence established and results of--different--treatments compared. A classification system should be simple to use, reliable and uniformly accepted. It should allow space for adaptations and/or extensions. The IFSSH proposed a 7 categories classification based on the proposed classification of Swanson et al. in 1976. This classification, was based on, which was thought in the seventies, etiopathogenic pathways. These 7 groups are: I. Failure of formation; transverse (A), or longitudinal (B) II. Failure of differentiation III. Polydactyly IV. Overgrowth V. Undergrowth VI. Amniotic band syndrome VII. Generalized skeletal syndromes. The extended classification proposed by IFSSH was used to classify 1013 hand differences in 925 hands of 650 patients. We found associated anomalies in 26.7%. The classification was straightforward in 86%, difficult in 6.6% and not possible in 7.8%. Group II was the most numerous group including 513 anomalies. We propose to include in this group the Madelung deformity, the Kirner deformity and congenital trigger fingers and trigger thumbs. In group I the radial and ulnar deficiencies, limited to the hand without forearm deficlencies should be Included. Triphalangeal thumbs are a problem, we suggest it to be listed in group III and consider it as a duplication in length. It is not always possible to evaluate the (transverse) absence of the fingers or hand. Longitudinal deficiencies (group IIB), symbrachydactyly (group V), and amniotic bands (group IV) occasionally develop a phenotype similar to the genuine transverse deficiency (group IA). Recently, the Japanese Society for Surgery of the Hand (JSSH) (16) proposed an extension

Deformation mechanisms in experimentally deformed Boom Clay

NASA Astrophysics Data System (ADS)

Desbois, Guillaume; Schuck, Bernhard; Urai, Janos

2016-04-01

Bulk mechanical and transport properties of reference claystones for deep disposal of radioactive waste have been investigated since many years but little is known about microscale deformation mechanisms because accessing the relevant microstructure in these soft, very fine-grained, low permeable and low porous materials remains difficult. Recent development of ion beam polishing methods to prepare high quality damage free surfaces for scanning electron microscope (SEM) is opening new fields of microstructural investigation in claystones towards a better understanding of the deformation behavior transitional between rocks and soils. We present results of Boom Clay deformed in a triaxial cell in a consolidated - undrained test at a confining pressure of 0.375 MPa (i.e. close to natural value), with σ1 perpendicular to the bedding. Experiments stopped at 20 % strain. As a first approximation, the plasticity of the sample can be described by a Mohr-Coulomb type failure envelope with a coefficient of cohesion C = 0.117 MPa and an internal friction angle ϕ = 18.7°. After deformation test, the bulk sample shows a shear zone at an angle of about 35° from the vertical with an offset of about 5 mm. We used the "Lamipeel" method that allows producing a permanent absolutely plane and large size etched micro relief-replica in order to localize and to document the shear zone at the scale of the deformed core. High-resolution imaging of microstructures was mostly done by using the BIB-SEM method on key-regions identified after the "Lamipeel" method. Detailed BIB-SEM investigations of shear zones show the following: the boundaries between the shear zone and the host rock are sharp, clay aggregates and clastic grains are strongly reoriented parallel to the shear direction, and the porosity is significantly reduced in the shear zone and the grain size is smaller in the shear zone than in the host rock but there is no evidence for broken grains. Comparison of microstructures

The Whole-Hand Point: The Structure and Function of Pointing From a Comparative Perspective

PubMed Central

Leavens, David A.; Hopkins, William D.

2007-01-01

Pointing by monkeys, apes, and human infants is reviewed and compared. Pointing with the index finger is a species-typical human gesture, although human infants exhibit more whole-hand pointing than is commonly appreciated. Captive monkeys and feral apes have been reported to only rarely “spontaneously” point, although apes in captivity frequently acquire pointing, both with the index finger and with the whole hand, without explicit training. Captive apes exhibit relatively more gaze alternation while pointing than do human infants about 1 year old. Human infants are relatively more vocal while pointing than are captive apes, consistent with paralinguistic use of pointing. PMID:10608565

Melorheostosis of the hand affecting the c6 sclerotome and presenting with carpal tunnel syndrome

PubMed Central

Abdullah, Shalimar; Nor, Noreen Fazlina Mat; Haflah, Nor Hazla Mohamed

2014-01-01

Melorheostosis is a rare, progressive bone disease accompanied by hyperostosis and soft tissue fibrosis. While affected adults present with contracture and pain, children present with limb length discrepancy and deformity. We report the case of a 20-year-old woman with melorheostosis since childhood who presented with right hand deformity and numbness. Radiographs showed not only a combination of dense sclerosis and opacities, but also the classic ‘flowing candle wax’ appearance. Radiography can be used to identify melorheostosis, thus preventing unnecessary bone biopsies. Carpal tunnel release revealed the presence of a thickened flexor retinaculum and a degenerated median nerve distal to the retinaculum, but did not show hyperostosis. This case highlights the role of nerve decompression in melorheostosis and the importance of early identification of the disease to prevent unnecessary bone biopsies. PMID:24763843

Melorheostosis of the hand affecting the c6 sclerotome and presenting with carpal tunnel syndrome.

PubMed

Abdullah, Shalimar; Mat Nor, Noreen Fazlina; Mohamed Haflah, Nor Hazla

2014-04-01

Melorheostosis is a rare, progressive bone disease accompanied by hyperostosis and soft tissue fibrosis. While affected adults present with contracture and pain, children present with limb length discrepancy and deformity. We report the case of a 20-year-old woman with melorheostosis since childhood who presented with right hand deformity and numbness. Radiographs showed not only a combination of dense sclerosis and opacities, but also the classic 'flowing candle wax' appearance. Radiography can be used to identify melorheostosis, thus preventing unnecessary bone biopsies. Carpal tunnel release revealed the presence of a thickened flexor retinaculum and a degenerated median nerve distal to the retinaculum, but did not show hyperostosis. This case highlights the role of nerve decompression in melorheostosis and the importance of early identification of the disease to prevent unnecessary bone biopsies.

From progressive to finite deformation, and back: the universal deformation matrix

NASA Astrophysics Data System (ADS)

Provost, A.; Buisson, C.; Merle, O.

2003-04-01

It is widely accepted that any finite strain recorded in the field may be interpreted in terms of the simultaneous combination of a pure shear component with one or several simple shear components. To predict strain in geological structures, approximate solutions may be obtained by multiplying successive small increments of each elementary strain component. A more rigorous method consists in achieving the simultaneous combination in the velocity gradient tensor but solutions already proposed in the literature are valid for special cases only and cannot be used, e.g., for the general combination of a pure shear component and six elementary simple shear components. In this paper, we show that the combination of any strain components is as simple as a mouse click, both analytically and numerically. The finite deformation matrix is given by L=exp(L.Δt) where L.Δt is the time-integrated velocity gradient tensor. This method makes it possible to predict finite strain for any combination of strain components. Reciprocally, L.Δt=ln(D) , which allows to unravel the simplest deformation history that might be liable for a given finite deformation. Given the strain ellipsoid only, it is still possible to constrain the range of compatible deformation matrices and thus the range of strain component combinations. Interestingly, certain deformation matrices, though geologically sensible, have no real logarithm so cannot be explained by a deformation history implying strain rate components with constant proportions, what implies significant changes of the stress field during the history of deformation. The study as a whole opens the possibility for further investigations on deformation analysis in general, the method could be used wathever the configuration is.

Monitoring Deformation in Graphene Through Hyperspectral Synchrotron Spectroscopy to Inform Fabrication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winter, Allen Douglas; Rojas, Wudmir Y.; Williams, Adrienne D.

The promise from graphene to produce devices with high mobilities and detectors with fast response times is truncated in practice by strain and deformation originating during growth and subsequent processing. This work describes effects from graphene growth, multiple layer transfer, and substrate termination on out of plane deformation, critical to device performance. Synchrotron spectroscopy data was acquired with a state-of-the-art hyperspectral large-area detector to describe growth and processing with molecular sensitivity at wafer length scales. A study of methodologies used in data analysis discouraged dichroic ratio approaches in favor of orbital vector approximations and data mining algorithms. Orbital vector methodsmore » provide a physical insight into mobility-detrimental rippling by identifying ripple frequency as main actor, rather than intensity; which was confirmed by data mining algorithms, and in good agreement with electron scattering theories of corrugation in graphene. This work paves the way to efficient information from mechanical properties in graphene in a high throughput mode throughout growth and processing in a materials by design approach.« less

Analysis on the misalignment errors between Hartmann-Shack sensor and 45-element deformable mirror

NASA Astrophysics Data System (ADS)

Liu, Lihui; Zhang, Yi; Tao, Jianjun; Cao, Fen; Long, Yin; Tian, Pingchuan; Chen, Shangwu

2017-02-01

Aiming at 45-element adaptive optics system, the model of 45-element deformable mirror is truly built by COMSOL Multiphysics, and every actuator's influence function is acquired by finite element method. The process of this system correcting optical aberration is simulated by making use of procedure, and aiming for Strehl ratio of corrected diffraction facula, in the condition of existing different translation and rotation error between Hartmann-Shack sensor and deformable mirror, the system's correction ability for 3-20 Zernike polynomial wave aberration is analyzed. The computed result shows: the system's correction ability for 3-9 Zernike polynomial wave aberration is higher than that of 10-20 Zernike polynomial wave aberration. The correction ability for 3-20 Zernike polynomial wave aberration does not change with misalignment error changing. With rotation error between Hartmann-Shack sensor and deformable mirror increasing, the correction ability for 3-20 Zernike polynomial wave aberration gradually goes down, and with translation error increasing, the correction ability for 3-9 Zernike polynomial wave aberration gradually goes down, but the correction ability for 10-20 Zernike polynomial wave aberration behave up-and-down depression.

TU-H-CAMPUS-JeP1-05: Dose Deformation Error Associated with Deformable Image Registration Pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Surucu, M; Woerner, A; Roeske, J

Purpose: To evaluate errors associated with using different deformable image registration (DIR) pathways to deform dose from planning CT (pCT) to cone-beam CT (CBCT). Methods: Deforming dose is controversial because of the lack of quality assurance tools. We previously proposed a novel metric to evaluate dose deformation error (DDE) by warping dose information using two methods, via dose and contour deformation. First, isodose lines of the pCT were converted into structures and then deformed to the CBCT using an image based deformation map (dose/structure/deform). Alternatively, the dose matrix from the pCT was deformed to CBCT using the same deformation map,more » and then the same isodose lines of the deformed dose were converted into structures (dose/deform/structure). The doses corresponding to each structure were queried from the deformed dose and full-width-half-maximums were used to evaluate the dose dispersion. The difference between the FWHM of each isodose level structure is defined as the DDE. Three head-and-neck cancer patients were identified. For each patient, two DIRs were performed between the pCT and CBCT, either deforming pCT-to-CBCT or CBCT-to-pCT. We evaluated the errors associated by using either of these pathways to deform dose. A commercially available, Demons based DIR was used for this study, and 10 isodose levels (20% to 105%) were used to evaluate the errors in various dose levels. Results: The prescription dose for all patients was 70 Gy. The mean DDE for CT-to-CBCT deformation was 1.0 Gy (range: 0.3–2.0 Gy) and this was increased to 4.3 Gy (range: 1.5–6.4 Gy) for CBCT-to-CT deformation. The mean increase in DDE between the two deformations was 3.3 Gy (range: 1.0–5.4 Gy). Conclusion: The proposed DDF was used to quantitatively estimate dose deformation errors caused by different pathways to perform DIR. Deforming dose using CBCT-to-CT deformation produced greater error than CT-to-CBCT deformation.« less

Tensile deformation and recovery kinetics of Alloy 690. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, C.F.; Mayo, W.E.; Weissmann, S.

1992-07-01

The effect of carbon content, grain size and thermal history on the deformation behavior of nickel-base Alloy 690 has been investigated. Carbon content effects the yield strength of Mill Annealed (MA) material, but has no effect in Thermally Treated (TT) material. Also, no effect of carbon content on the workhardening rate was seen in either material. There was an effect of grain size as expected. An interesting aspect of this work showed that TT material consistently has a slightly higher Young`s modulus than the MA. As deformation moves into the plastic regime, the TT material displays a two stage hardeningmore » process. This consists of a low workhardening rate (n = 0.05), followed by a transition to the more normal workhardening rate (n=0.35). The MA material, on the other hand, does not exhibit the low n region. This unusual deformation behavior is attributable to the presence of planar slip which initiates at the grain boundary over the strain range of 0.2 to 0.7%. These observations are useful to explain the unexpectedly fast strain relaxation behavior seen in this alloy. The recovery kinetics of the alloy have also been studied. Rapid recovery with an activation energy of approximately 5.3 kj/mol occurs when the deformation level is low. This was attributed to a grain boundary self diffusion process. At higher strain levels, recovery is much slower with an activation energy of approximately 14 kJ/mol. This process was attributable to bulk diffusion. Based on TEM and X-ray rocking curve measurements, these results have been explained.« less

Shear Deformation of Fe Polycrystals in the Rotational Diamond Anvil Cell

NASA Astrophysics Data System (ADS)

Merkel, S.; Lincot, A.; Nisr, C.; Hanfland, M.; Zerr, A.

2014-12-01

For many years, experiments are being developed for performing deformation experiments under lower mantle conditions. They include methods such as the Deformation-DIA (Wang et al, 2003) or radial x-ray diffraction in the diamond anvil cell (Merkel et al, 2002). However, the strain applied to the sample is typically limited to about 40%. This can be an issue for studying effects of large deformation or, for the case of diamond anvil cells, applying actual plastic strain at megabar pressures. The issue can be solved using apparatus such as the Rotational-Drickamer (RDA) (e.g. Yamazaki and Karato, 2001). However, the RDA offers limited diffraction access to the sample and operating pressures do not reach those of the lower mantle.In this abstract, we investigate the potential applications of the rotational diamond anvil cell (Rot-DAC) for such studies. 300 K experiments in the Rot-DAC have been performed up to pressures exceeding 50 GPa (e.g. Serebryanaya et al, 1995) with studies focusing on the effect of shear on solid-solid phase transformation pressures. The authors did not investigate the possibility of using the Rot-DAC for studying rheological properties.Here, a sample of polycrystalline Fe is submitted to shear deformation in the Rot-DAC at pressures up to 20 GPa. Synchrotron X-ray diffraction and Rietveld refinements are then used to study the texture and stress state at multiple locations in the sample. The study shows that the Rot-DAC is efficient at producing deformation textures in a polycrystalline aggregate but that care should be taken in ensuring that the sample is actually undergoing plastic deformation and not solid rotation. Stresses, on the other hand, are difficult to extract from the x-ray diffraction data because of lack of understanding of stress distributions in the deforming aggregate.S. Merkel, H. R. Wenk, J. Shu, G. Shen, P. Gillet, H. K. Mao and R. J. Hemley, J. Geophys. Res., 107, 2271 (2002)N. Serebryanaya, V. Blank and V. Ivdenko, Phys

Fast elastic registration of soft tissues under large deformations.

PubMed

Peterlík, Igor; Courtecuisse, Hadrien; Rohling, Robert; Abolmaesumi, Purang; Nguan, Christopher; Cotin, Stéphane; Salcudean, Septimiu

2018-04-01

A fast and accurate fusion of intra-operative images with a pre-operative data is a key component of computer-aided interventions which aim at improving the outcomes of the intervention while reducing the patient's discomfort. In this paper, we focus on the problematic of the intra-operative navigation during abdominal surgery, which requires an accurate registration of tissues undergoing large deformations. Such a scenario occurs in the case of partial hepatectomy: to facilitate the access to the pathology, e.g. a tumor located in the posterior part of the right lobe, the surgery is performed on a patient in lateral position. Due to the change in patient's position, the resection plan based on the pre-operative CT scan acquired in the supine position must be updated to account for the deformations. We suppose that an imaging modality, such as the cone-beam CT, provides the information about the intra-operative shape of an organ, however, due to the reduced radiation dose and contrast, the actual locations of the internal structures necessary to update the planning are not available. To this end, we propose a method allowing for fast registration of the pre-operative data represented by a detailed 3D model of the liver and its internal structure and the actual configuration given by the organ surface extracted from the intra-operative image. The algorithm behind the method combines the iterative closest point technique with a biomechanical model based on a co-rotational formulation of linear elasticity which accounts for large deformations of the tissue. The performance, robustness and accuracy of the method is quantitatively assessed on a control semi-synthetic dataset with known ground truth and a real dataset composed of nine pairs of abdominal CT scans acquired in supine and flank positions. It is shown that the proposed surface-matching method is capable of reducing the target registration error evaluated of the internal structures of the organ from more than

Fluid flow simulation and permeability computation in deformed porous carbonate grainstones

NASA Astrophysics Data System (ADS)

Zambrano, Miller; Tondi, Emanuele; Mancini, Lucia; Lanzafame, Gabriele; Trias, F. Xavier; Arzilli, Fabio; Materazzi, Marco; Torrieri, Stefano

2018-05-01

In deformed porous carbonates, the architecture of the pore network may be modified by deformation or diagenetic processes altering the permeability with respect to the pristine rock. The effects of the pore texture and morphology on permeability in porous rocks have been widely investigated due to the importance during the evaluation of geofluid reservoirs. In this study, these effects are assessed by combining synchrotron X-ray computed microtomography (SR micro-CT) and computational fluid dynamics. The studied samples pertain to deformed porous carbonate grainstones highly affected by deformation bands (DBs) exposed in Northwestern Sicily and Abruzzo regions, Italy. The high-resolution SR micro-CT images of the samples, acquired at the SYRMEP beamline of the Elettra - Sincrotrone Trieste laboratory (Italy), were used for simulating a pressure-driven flow by using the lattice-Boltzmann method (LBM). For the experiments, a multiple relaxation time (MRT) model with the D3Q19 scheme was used to avoid viscosity-dependent results of permeability. The permeability was calculated using Darcy's law once steady conditions were reached. After the simulations, the pore-network properties (effective porosity, specific surface area, and geometrical tortuosity) were calculated using 3D images of the velocity fields. These images were segmented considering a velocity threshold value higher than zero. The study showed that DBs may generate significant heterogeneity and anisotropy of the permeability of the evaluated rock samples. Cataclasis and cementation process taking place within the DBs reduce the effective porosity and therefore the permeability. Contrary to this, pressure dissolution and faulting may generate connected channels which contribute to the permeability only parallel to the DB.

Comparison of defects in ProTaper hand-operated and engine-driven instruments after clinical use.

PubMed

Cheung, G S P; Bian, Z; Shen, Y; Peng, B; Darvell, B W

2007-03-01

To compare the type of defects and mode of material failure of engine-driven and hand-operated ProTaper instruments after clinical use. A total of 401 hand-operated and 325 engine-driven ProTaper instruments were discarded from an endodontic clinic over 17 months. Those that had fractured were examined for plastic deformation in lateral view and remounted for fractographical examination in scanning electron microscope. The mode of fracture was classified as 'fatigue' or 'shear' failure. The lengths of fractured segments in both instruments were recorded. Any distortion in hand instrument was noted. Data were analysed using chi-square, Fisher's exact or Student's t-test, where appropriate. Approximately 14% of all discarded hand-operated instruments and 14% of engine-driven instruments were fractured. About 62% of hand instruments failed because of shear fracture, compared with approximately 66% of engine-driven instruments as a result of fatigue (P < 0.05). Approximately 16% of hand instruments were affected by shear, and either remained intact or was fractured, compared with 5% of engine-driven instruments (P < 0.05). The length of the broken fragment was significantly shorter in hand versus engine-driven group (P < 0.05). Approximately 7% of hand instruments were discarded intact but distorted (rarely for engine-driven instruments); all were in the form of unscrewing of the flutes. The location of defects in hand Finishing instruments was significantly closer to the tip than that for Shaping instruments (P < 0.05). Under the conditions of this study (possibly high usage), the failure mode of ProTaper engine-driven and hand-operated instruments appeared to be different, with shear failure being more prevalent in the latter.

Hand-eye calibration using a target registration error model.

PubMed

Chen, Elvis C S; Morgan, Isabella; Jayarathne, Uditha; Ma, Burton; Peters, Terry M

2017-10-01

Surgical cameras are prevalent in modern operating theatres and are often used as a surrogate for direct vision. Visualisation techniques (e.g. image fusion) made possible by tracking the camera require accurate hand-eye calibration between the camera and the tracking system. The authors introduce the concept of 'guided hand-eye calibration', where calibration measurements are facilitated by a target registration error (TRE) model. They formulate hand-eye calibration as a registration problem between homologous point-line pairs. For each measurement, the position of a monochromatic ball-tip stylus (a point) and its projection onto the image (a line) is recorded, and the TRE of the resulting calibration is predicted using a TRE model. The TRE model is then used to guide the placement of the calibration tool, so that the subsequent measurement minimises the predicted TRE. Assessing TRE after each measurement produces accurate calibration using a minimal number of measurements. As a proof of principle, they evaluated guided calibration using a webcam and an endoscopic camera. Their endoscopic camera results suggest that millimetre TRE is achievable when at least 15 measurements are acquired with the tracker sensor ∼80 cm away on the laparoscope handle for a target ∼20 cm away from the camera.

A Least Square Approach for Joining Persistent Scatterer InSAR Time Series Acquired by Different Satellites

NASA Astrophysics Data System (ADS)

Caro Cuenca, Miguel; Esfahany, Sami Samiei; Hanssen, Ramon F.

2010-12-01

Persistent scatterer Radar Interferometry (PSI) can provide with a wealth of information on surface motion. These methods overcome the major limitations of the antecessor technique, interferometric SAR (InSAR), such as atmospheric disturbances, by detecting the scatterers which are slightly affected by noise. The time span that surface deformation processes are observed is limited by the satellite lifetime, which is usually less than 10 years. However most of deformation phenomena last longer. In order to fully monitor and comprehend the observed signal, acquisitions from different sensors can be merged. This is a complex task for one main reason. PSI methods provide with estimations that are relative in time to one of the acquisitions which is referred to as master or reference image. Therefore, time series acquired by different sensors will have different reference images and cannot be directly compared or joint unless they are set to the same time reference system. In global terms, the operation of translating from one to another reference systems consist of calculating a vertical offset, which is the total deformation that occurs between the two master times. To estimate this offset, different strategies can be applied, for example, using additional data such as leveling or GPS measurements. In this contribution we propose to use a least squares to merge PSI time series without any ancillary information. This method treats the time series individually, i.e. per PS, and requires some knowledge of the deformation signal, for example, if a polynomial would fairly describe the expected behavior. To test the proposed approach, we applied it to the southern Netherlands, where the surface is affected by ground water processes in abandoned mines. The time series were obtained after processing images provided by ERS1/2 and Envisat. The results were validated using in-situ water measurements, which show very high correlation with deformation time series.

Integration of Space-borne SAR and Ground-Based Radar for 3D Deformation Mapping of the Central Calaveras Fault at Coyote Dam

NASA Astrophysics Data System (ADS)

Werner, C. L.; Baker, B.; Milillo, P.; Magnard, C.; Strozzi, T.; Wegmüller, U.

2017-12-01

The Central Calaveras Fault (CCF) passes directly through Coyote Dam located southeast of Morgan Hill, California. This earthen embankment dam owned and operated by the Santa Clara Valley Water District (District), has experienced over 80 cm of accumulated fault creep since its construction in 1936. The average slip rate is 10 to 15 mm/year as measured using surveying, GPS, and more recently, terrestrial radar interferometry (TRI). The CCF is a right-lateral strike-slip fault that has the potential for a M7.25 earthquake resulting in meter scale displacement. In 2015, the District initiated a geological analysis of the CCF integrating past surveying, GPS data, TRI deformation mapping, paleoseismic trenching, and boreholes. The initial TRI survey included dam measurements from two locations, imaging the upstream and downstream embankments over the period from February to July 2015. The TRI data from the downstream embankment data showed a complex deformation pattern not consistent with a strike-slip fault model. A second measurement campaign was initiated utilizing multiple radar viewpoints with the aim of resolving the 3D deformation field of the downstream embankment. The campaign occurred between May and November 2016 and showed an unexpected strong westward and downward movement exceeding 2 cm/year (see Figure). TRI data were acquired from 4 separate observation points every 2 to 4 weeks during this campaign. Point target analysis methods were used to avoid contamination of the deformation data by vegetation and radar shadow. Deformation uncertainty in the downstream fault zone was relatively high due to the nearly coplanar arrangement of the TRI observation points. To better constrain the vertical deformation, in this report we integrate spaceborne measurements from the Cosmo-SkyMed (CS) radar satellite in the 3D deformation solution. The LOS to the satellite has a large vertical component not present in the TRI measurement geometry that facilitates the

Monitoring Volcano Deformation in the Northernmost Andes with ALOS InSAR Time-Series

NASA Astrophysics Data System (ADS)

Morales Rivera, A. M.; Amelung, F.

2014-12-01

Satellite-based Interferometric Synthetic Aperture Radar (InSAR) is well known to be used as a volcano monitoring tool, providing the opportunity to conduct local and regional surveys to detect and measure volcanic deformation. The signals detected by InSAR on volcanoes can be related to various phenomena, such as volume changes in magmatic reservoirs, compaction of recent deposits, changes in hydrothermal activity, and flank instability. The InSAR time-series method has well documented examples of these phenomena, including precursory inflation of magma reservoirs months prior to volcanic eruptions, proving its potential for early warning systems. We use the ALOS-1 satellite from the Japanese Aerospace Exploration Agency (JAXA), which acquired a global L-band data set of nearly 20 acquisitions during 2007-2011, to make an InSAR time-series analysis using the Small Baseline method (SBAS). Our analysis covers all of the volcanoes in Colombia, Ecuador, and Peru that are cataloged by the Global Volcanism Program. We present results showing time-dependent ground deformation on an near the volcanoes, and present kinematic models to constrain the characteristics of the magmatic sources for the cases in which the deformation is likely related to changes in magma reservoir pressurization.

Linear friction weld process monitoring of fixture cassette deformations using empirical mode decomposition

NASA Astrophysics Data System (ADS)

Bakker, O. J.; Gibson, C.; Wilson, P.; Lohse, N.; Popov, A. A.

2015-10-01

Due to its inherent advantages, linear friction welding is a solid-state joining process of increasing importance to the aerospace, automotive, medical and power generation equipment industries. Tangential oscillations and forge stroke during the burn-off phase of the joining process introduce essential dynamic forces, which can also be detrimental to the welding process. Since burn-off is a critical phase in the manufacturing stage, process monitoring is fundamental for quality and stability control purposes. This study aims to improve workholding stability through the analysis of fixture cassette deformations. Methods and procedures for process monitoring are developed and implemented in a fail-or-pass assessment system for fixture cassette deformations during the burn-off phase. Additionally, the de-noised signals are compared to results from previous production runs. The observed deformations as a consequence of the forces acting on the fixture cassette are measured directly during the welding process. Data on the linear friction-welding machine are acquired and de-noised using empirical mode decomposition, before the burn-off phase is extracted. This approach enables a direct, objective comparison of the signal features with trends from previous successful welds. The capacity of the whole process monitoring system is validated and demonstrated through the analysis of a large number of signals obtained from welding experiments.

Venous pooling and drainage affects photoplethysmographic signals at different vertical hand positions

NASA Astrophysics Data System (ADS)

Hickey, Michelle; Phillips, Justin P.; Kyriacou, Panayiotis

2015-03-01

The aim of the current work is to investigate the possibility of augmenting pulse oximetry algorithms to enable the estimation of venous parameters in peripheral tissues. In order to further understand the contribution of venous blood to the photoplethysmographic (PPG) signal, recordings were made from six healthy volunteer subjects during an exercise in which the right hand was placed in various positions above and below heart level. The left hand was kept at heart level as a control while the right hand was moved. A custom-made two-channel dual wavelength PPG instrumentation system was used to obtain the red and infrared plethysmographic signals from both the right and left index fingers simultaneously using identical sensors. Laser Doppler flowmetry signals were also recorded from an adjacent fingertip on the right hand. Analysis of all acquired PPG signals indicated changes in both ac and dc amplitude of the right hand when the position was changed, while those obtained from the left (control) hand remained relatively constant. Most clearly, in the change from heart level to 50cm below heart level there is a substantial decrease in both dc and ac amplitudes. This decrease in dc amplitude most likely corresponds to increased venous pooling, and hence increased absorption of light. It is speculated that the decrease in ac PPG amplitude is due to reduced arterial emptying during diastole due to increased downstream resistance due to venous pooling.

12 CFR 583.1 - Acquire.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Acquire. 583.1 Section 583.1 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY DEFINITIONS FOR REGULATIONS AFFECTING SAVINGS AND LOAN HOLDING COMPANIES § 583.1 Acquire. The term acquire means to acquire, directly or indirectly...

Holocene Flexural Deformation over the Nile Delta: Evidence from Radar Interferometry

NASA Astrophysics Data System (ADS)

Gebremichael, E.; Sultan, M.; Becker, R.

2017-12-01

Isostatic adjustment and subsequent subsidence and uplift due to sediment and water loading and unloading mechanisms is one of the major factors that produce regional deformational patterns across river deltas. Using 84 Envisat ASAR scenes that were acquired (2004 - 2010) along three tracks and applying Persistent scatterer (PS) radar interferometric techniques, we documented flexural deformational patterns over the entire Nile Delta (length: 186 km; width: 240 km) of Egypt. The passive continental margin of Africa subsided from Jurassic time onwards due to isostatic loading creating an accommodation space and consequently, the deposition of relatively younger sediments on the oceanic crust. In river deltas, the flexural isostasy model dictates that a subsidence in the oceanic crust side should be balanced by a bulge (uplift) in the flanking regions. Using radar interferometry, we were able to identify the flexural deformation pattern and map its spatial extent over the northern and central Nile Delta region. Findings include: (1) the northern Nile Delta region (block) is separated from the southern delta region by an east-west trending, extensively faulted, hinge line that signifies the boundary between two deformational patterns (subsidence and uplift). It separates the highly subsiding (up to 9.8 mm/yr) northern delta block (up to 85 km long) from the nearly stable (0.4 mm/yr; averaged) southern delta block (up to 91 km long). The hinge line marks the end of the passive continental margin of Africa and the beginning of the oceanic crust of the Mediterranean. (2) We mapped the extent of a 20-40 km wide flexural uplift zone to the south of the hinge line. Within the flexural uplift zone (2.5 mm/yr; averaged), there is a gradual increase in uplift rate reaching peak value (up to 7 mm/yr) near the midpoint of the zone. (3) The uplift rate gradually decreases south of the flexure boundary reaching 0.3 mm/yr at the southern periphery of the delta. (4) The flexural

Jordanian deformation of SL(2) as a contraction of its Drinfeld-Jimbo deformation

NASA Astrophysics Data System (ADS)

Aghamohammadi, A.; Khorrami, M.; Shariati, A.

1995-04-01

We show that $h$-deformation can be obtained, by a singular limit of a similarity transformation, from $q$-deformation; to be specefic, we obtain $\\GL_h(2)$, its differential structure, its inhomogenous extension, and $\\Uh{\\sl(2)}$ from their $q$-deformed counterparts.

Mental Practice Combined with Physical Practice to Enhance Hand Recovery in Stroke Patients

PubMed Central

Liu, Hua; Song, Lu-ping

2014-01-01

Objectives. To evaluate whether combining mental practice with physical practice training enhances hand function in patients with stroke. Methods. 10 for treatment and 10 for control were recruited for this pre/posttraining matched case control study. In the treatment group, subjects underwent combining mental practice with physical practice for four weeks. In the control group, subjects only participated in physical practice. Change of hand function and the number of activated voxels of the contralateral somatosensory motor cortex (SMC) acquired by functional magnetic resonance imaging were measured. Results. After training, the Action Research Arm Test score increased by 12.65 for treatment and by 5.20 for control. There was a significant difference in the Action Research Arm Test score between the two groups (P = 0.04). The activated voxels number of the contralateral SMC increased in both groups, but the activated voxels number in the contralateral SMC and the improvement of hand function for treatment were greater than for control. In the treatment group, the number of activated voxels of the contralateral SMC was positively correlated with better hand function scores. Conclusions. Combining mental practice with physical practice may be a more effective treatment strategy than physical training alone for hand recovery in stroke patients. PMID:25435713

Deformations of superconformal theories

DOE PAGES

Córdova, Clay; Dumitrescu, Thomas T.; Intriligator, Kenneth

2016-11-22

Here, we classify possible supersymmetry-preserving relevant, marginal, and irrelevant deformations of unitary superconformal theories in d ≥ 3 dimensions. Our method only relies on symmetries and unitarity. Hence, the results are model independent and do not require a Lagrangian description. Two unifying themes emerge: first, many theories admit deformations that reside in multiplets together with conserved currents. Such deformations can lead to modifications of the supersymmetry algebra by central and noncentral charges. Second, many theories with a sufficient amount of supersymmetry do not admit relevant or marginal deformations, and some admit neither. The classification is complicated by the fact thatmore » short superconformal multiplets display a rich variety of sporadic phenomena, including supersymmetric deformations that reside in the middle of a multiplet. We illustrate our results with examples in diverse dimensions. In particular, we explain how the classification of irrelevant supersymmetric deformations can be used to derive known and new constraints on moduli-space effective actions.« less

Road Signs Detection and Recognition Utilizing Images and 3d Point Cloud Acquired by Mobile Mapping System

NASA Astrophysics Data System (ADS)

Li, Y. H.; Shinohara, T.; Satoh, T.; Tachibana, K.

2016-06-01

High-definition and highly accurate road maps are necessary for the realization of automated driving, and road signs are among the most important element in the road map. Therefore, a technique is necessary which can acquire information about all kinds of road signs automatically and efficiently. Due to the continuous technical advancement of Mobile Mapping System (MMS), it has become possible to acquire large number of images and 3d point cloud efficiently with highly precise position information. In this paper, we present an automatic road sign detection and recognition approach utilizing both images and 3D point cloud acquired by MMS. The proposed approach consists of three stages: 1) detection of road signs from images based on their color and shape features using object based image analysis method, 2) filtering out of over detected candidates utilizing size and position information estimated from 3D point cloud, region of candidates and camera information, and 3) road sign recognition using template matching method after shape normalization. The effectiveness of proposed approach was evaluated by testing dataset, acquired from more than 180 km of different types of roads in Japan. The results show a very high success in detection and recognition of road signs, even under the challenging conditions such as discoloration, deformation and in spite of partial occlusions.

Acquired neuropathies.

PubMed

Lozeron, Pierre; Trocello, Jean-Marc; Kubis, Nathalie

2013-09-01

Acquired neuropathies represent most of the neuropathies encountered in clinical practice. Hundreds of causes have been identified even though up to 41% of patients are still classified as idiopathic (Rajabally and Shah in J Neurol 258:1431-1436, 1). Routine evaluation relies on comprehensive medical history taking, clinical examination, nerve conduction studies and laboratory tests. Other investigations such as nerve biopsy or nerve or muscle imaging are performed in specific settings. This review focuses on recent advances in acquired neuropathies.

The utility of hand transplantation in hand amputee patients.

PubMed

Alolabi, Noor; Chuback, Jennifer; Grad, Sharon; Thoma, Achilles

2015-01-01

To measure the desirable health outcome, termed utility, and the expected quality-adjusted life years (QALYs) gained with hand composite tissue allotransplantation (CTA) using hand amputee patients and the general public. Using the standard gamble (SG) and time trade-off (TTO) techniques, utilities were obtained from 30 general public participants and 12 amputee patients. The health utility and net QALYs gained or lost with transplantation were computed. A sensitivity analysis was conducted to account for the effects of lifelong immunosuppression on the life expectancy of transplant recipients. Higher scores represent greater utility. Hand amputation mean health utility as measured by the SG and TTO methods, respectively, was 0.72 and 0.80 for the general public and 0.69 and 0.70 for hand amputees. In comparison, hand CTA mean health utility was 0.74 and 0.82 for the general public and 0.83 and 0.86 for amputees. Hand CTA imparted an expected gain of 0.9 QALYs (SG and TTO) in the general public and 7.0 (TTO) and 7.8 (SG) QALYs in hand amputees. A loss of at least 1.7 QALYs was demonstrated when decreasing the life expectancy in the sensitivity analysis in the hand amputee group. Hand amputee patients did not show a preference toward hand CTA with its inherent risks. With this procedure being increasingly adopted worldwide, the benefits must be carefully weighed against the risks of lifelong immunosuppressive therapy. This study does not show clear benefit to advocate hand CTA. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Ocean deformation processes at the Caribbean-North America-South America triple junction: Initial results of the 2007 ANTIPLAC marine survey

NASA Astrophysics Data System (ADS)

Benard, F.; Deville, E.; Le Drezen, E.; Loubrieu, B.; Maltese, L.; Patriat, M.; Roest, W.; Thereau, E.; Umber, M.; Vially, R.

2007-12-01

Marine geophysical data (multibeam and seismic lines) acquired in 2007 (ANTIPLAC survey) in the North-South Americas-Caribbean triple point (Central Atlantic, Barracuda and Tiburon ridges area), provide information about the structure, the tectonic processes and the timing of the deformation in this large diffuse zone of polyphase deformation. The deformation of the plate boundary between the north and south Americas is distributed on several structures located in the Atlantic plain, at the front of the Barbados accretionary prism. In this area of deformation of the Atlantic oceanic lithosphere, the main depressions and transform troughs are filled by Late Pliocene-Pleistocene turbidite sediments, especially in the Barracuda trough, north of Barracuda ridge. These sediments are not issued from the Lesser Antilles volcanic arc but they are sourced from the East, probably by the Orinoco turbidite distal system, through channels transiting in the Atlantic abyssal plain. These Late Pliocene- Quaternary sediments show locally spectacular evidences of syntectonic deformation. It can be shown notably that Barracuda ridge includes a pre-existing transform fault system which has been folded and uplifted very recently during Pleistocene times. This recent deformation has generate relieves up to 2 km high with associated erosion processes notably along the northern flank the Barracuda ridge. The subduction of these recently deformed ridges induces deformation of earlier structures within the Barbados accretionary prism. These asperities within the Atlantic oceanic lithosphere which is subducted in the Lesser Antilles active margin are correlated with the zone of intense seismic activity below the volcanic arc.

Earthquake mechanism and seafloor deformation for tsunami generation

USGS Publications Warehouse

Geist, Eric L.; Oglesby, David D.; Beer, Michael; Kougioumtzoglou, Ioannis A.; Patelli, Edoardo; Siu-Kui Au, Ivan

2014-01-01

Tsunamis are generated in the ocean by rapidly displacing the entire water column over a significant area. The potential energy resulting from this disturbance is balanced with the kinetic energy of the waves during propagation. Only a handful of submarine geologic phenomena can generate tsunamis: large-magnitude earthquakes, large landslides, and volcanic processes. Asteroid and subaerial landslide impacts can generate tsunami waves from above the water. Earthquakes are by far the most common generator of tsunamis. Generally, earthquakes greater than magnitude (M) 6.5–7 can generate tsunamis if they occur beneath an ocean and if they result in predominantly vertical displacement. One of the greatest uncertainties in both deterministic and probabilistic hazard assessments of tsunamis is computing seafloor deformation for earthquakes of a given magnitude.

Rheological properties of bridgmanite based on deformation experiments

NASA Astrophysics Data System (ADS)

Tsujino, N.; Yamazaki, D.; Yoshino, T.; Sakurai, M.; Higo, Y.; Tange, Y.

2017-12-01

The lower mantle occupies 65% of Earth's mantle. Therefore, rheology of the Earth's lower mantle is most important to understand dynamic processes in the Earth's mantle. In Tsujino et al. (2016), we developed deformation experimental technique using D-DIA apparatus as Kawai-type (6-8 type). Crystallographic-preferred-orientation (CPO) of bridgmanite at top of the Earth's lower mantle conditions was determined by shear deformation experiments under upper most lower mantle conditions (25 GPa and 1873 K). The observed seismic shear wave anisotropies near several subducted slabs (Tonga-Kermadec, Kurile, Peru and Java) can be explained in terms of the CPO of bridgmanite as induced by mantle flow parallel to the direction of subduction. On the other hands, one dimensional viscosity models of the Earth's mantle were proposed by geophysical observations while there are large inconsistencies of viscosity (2 3 order magnitude) in the lower mantle between suggested models. It is important to determine viscosity of lower mantle minerals by high pressure experiments in order to understand mantle dynamics. In this study, we conducted in-situ stress-strain measurements of MgSiO3-bridgmanite aggregate at 1473-1673 K and 24 GPa using D-DIA type apparatus as Kawai-type at Spring-8 BL04B1. Measured uniaxial stress, strain rate of bridgmanite during deformation experiments were 0.3-1.3 GPa and 4×10-6 - 3×10-5 /s with <6% strain. Creep strength of bridgmanite at 1×10-5 /s is largest in the mantle minerals and 0.5-1 order magnitude larger than those of transition minerals when only the results using D-DIA apparatus are compared.

Metamorphic reactions, grain size reduction and deformation of mafic lower crustal rocks

NASA Astrophysics Data System (ADS)

Degli Alessandrini, Giulia; Menegon, Luca; Beltrando, Marco; Dijkstra, Arjan; Anderson, Mark

2016-04-01

and their relative abundance in the layers are believed to influence the deformation of the layers themselves. In symplectite-rich layers (domains 1, 4) deformation is localised, grain-size is below 30μm and phases are well mixed. On the other hand, in pyroxene or plagioclase-rich layers, deformation is less localised, the phases are less mixed and the grain size is larger (domain 2, 3). These preliminary results suggest that syn-kinematic metamorphic reactions forming symplectites played an essential role in grain size reduction, phase mixing and strain localization. We speculate that the compositional domains with symplectites localized deformation more efficiently, by activation of grain size sensitive creep, most likely because those domains were originally more hydrated than the others. On the contrary, domains without symplectites accommodated deformation less efficiently, either through fracturing (clinopyroxene, garnet) or dislocation creep + recrystallization (orthopyroxene, plagioclase).

Investigation of Stability of Precise Geodetic Instruments Used in Deformation Monitoring

NASA Astrophysics Data System (ADS)

Woźniak, Marek; Odziemczyk, Waldemar

2017-12-01

Monitoring systems using automated electronic total stations are an important element of safety control of many engineering objects. In order to ensure the appropriate credibility of acquired data, it is necessary that instruments (total stations in most of the cases) used for measurements meet requirements of measurement accuracy, as well as the stability of instrument axis system geometry. With regards to the above, it is expedient to conduct quality control of data acquired using electronic total stations in the context of performed measurement procedures. This paper presents results of research conducted at the Faculty of Geodesy and Cartography at Warsaw University of Technology investigating the stability of "basic" error values (collimation, zero location for V circle, inclination), for two types of automatic total stations: TDA 5005 and TCRP 1201+. Research provided also information concerning the influence of temperature changes upon the stability of investigated instrument's optical parameters. Results are presented in graphical analytic technique. Final conclusions propose methods, which allow avoiding negative results of measuring tool-set geometry changes during conducting precise deformation monitoring measurements.

Analysis of radiographic bone parameters throughout the surgical lengthening and deformity correction of extremities.

PubMed

Atanasov, Nenad; Poposka, Anastasika; Samardziski, Milan; Kamnar, Viktor

2014-01-01

Radiographic examination of extremities in surgical lengthening and/or correction of deformities is of crucial importance for the assessment of new bone formation. The purpose of this study is to confirm the diagnostic value of radiography in precise detection of bone parameters in various lengthening or correction stages in patients treated by limb-lengthening and deformity correction. 50 patients were treated by the Ilizarov method of limb lengthening or deformity correction at the University Orthopaedic Surgery Clinic in Skopje, and analysed over the period from 2006 to 2012. The patients were divided into two groups. The first group consisted of 27 patients with limb-lengthening because of congenital shortening. The second group consisted of 23 patients treated for acquired limb deformities. The results in both groups were received in three stages of new bone formation and were based on the appearance of 3 radiographic parameters at the distraction/compression site. The differences between the presence of all radiographic bone parameters in different stages of new bone formation were statistically signficant in both groups, especially the presence of the cortical margin in the first group (Cochran Q=34.43, df=2, p=0.00000). The comparative analysis between the two groups showed a statistically significant difference in the presence of initial bone elements and cystic formations only in the first stage. Almost no statistical significance in the differences between both groups of patients with regard to 3 radiographic parameters in 3 stages of new bone formation, indicates a minor influence of the etiopathogenetic background on the new bone formation in patients treated by gradual lengthening or correction of limb deformities.

Advantages of formulating an evolution equation directly for elastic distortional deformation in finite deformation plasticity

NASA Astrophysics Data System (ADS)

Rubin, M. B.; Cardiff, P.

2017-11-01

Simo (Comput Methods Appl Mech Eng 66:199-219, 1988) proposed an evolution equation for elastic deformation together with a constitutive equation for inelastic deformation rate in plasticity. The numerical algorithm (Simo in Comput Methods Appl Mech Eng 68:1-31, 1988) for determining elastic distortional deformation was simple. However, the proposed inelastic deformation rate caused plastic compaction. The corrected formulation (Simo in Comput Methods Appl Mech Eng 99:61-112, 1992) preserves isochoric plasticity but the numerical integration algorithm is complicated and needs special methods for calculation of the exponential map of a tensor. Alternatively, an evolution equation for elastic distortional deformation can be proposed directly with a simplified constitutive equation for inelastic distortional deformation rate. This has the advantage that the physics of inelastic distortional deformation is separated from that of dilatation. The example of finite deformation J2 plasticity with linear isotropic hardening is used to demonstrate the simplicity of the numerical algorithm.

Hand Matters: Left-Hand Gestures Enhance Metaphor Explanation

ERIC Educational Resources Information Center

Argyriou, Paraskevi; Mohr, Christine; Kita, Sotaro

2017-01-01

Research suggests that speech-accompanying gestures influence cognitive processes, but it is not clear whether the gestural benefit is specific to the gesturing hand. Two experiments tested the "(right/left) hand-specificity" hypothesis for self-oriented functions of gestures: gestures with a particular hand enhance cognitive processes…

[Hand osteoarthritis].

PubMed

Šenolt, Ladislav

Hand osteoarthritis (OA) is a common chronic disorder causing pain and limitation of mobility of affected joints. The prevalence of hand OA increases with age and more often affects females. Clinical signs obviously do not correlate with radiographic findings - symptomatic hand OA affects approximately 26 % of adult subjects, but radiographic changes can be found in up to two thirds of females and half of males older than 55 years.Disease course differ among individual patients. Hand OA is a heterogeneous disease. Nodal hand OA is the most common subtype affecting interphalangeal joints, thumb base OA affects first carpometacarpal joint. Erosive OA represents a specific subtype of hand OA, which is associated with joint inflammation, more pain, functional limitation and erosive findings on radiographs.Treatment of OA is limited. Analgesics and nonsteroidal anti-inflammatory drugs are the only agents reducing symptoms. New insights into the pathogenesis of disease should contribute to the development of novel effective treatment of hand OA.

Deformations in VLBI antennas

NASA Technical Reports Server (NTRS)

Clark, T. A.; Thomsen, P.

1988-01-01

A study is presented of deformations in antennas with the emphasis on their influence on VLBI measurements. The GIFTS structural analysis program has been used to model the VLBI antenna in Fairbanks (Alaska). The report identifies key deformations and studies the effect of gravity, wind, and temperature. Estimates of expected deformations are given.

Experimental deformation of a mafic rock - interplay between fracturing, reaction and viscous deformation

NASA Astrophysics Data System (ADS)

Marti, Sina; Stünitz, Holger; Heilbronner, Renée; Plümper, Oliver; Drury, Martyn

2016-04-01

Deformation experiments were performed on natural Maryland Diabase (˜ 55% Plg, 42% Px, 3% accessories, 0.18 wt.-% H2O added) in a Griggs-type deformation apparatus in order to explore the brittle-viscous transition and the interplay between deformation and mineral reactions. Shear experiments at strain rates of ˜ 2e-5 /s are performed, at T=600, 700 and 800°C and confining pressures Pc=1.0 and 1.5 GPa. Deformation localizes in all experiments. Below 700°C, the microstructure is dominated by brittle deformation with a foliation formed by cataclastic flow and high strain accommodated along 3-5 major ultracataclasite shear bands. At 700°C, the bulk of the material still exhibits abundant microfractures, however, deformation localizes into an anastomosing network of shear bands (SB) formed from a fine-grained (<< 1 μm) mixture of newly formed Plg and Amph. These reaction products occur almost exclusively along syn-kinematic structures such as fractures and SB. Experiments at 800°C show extensive mineral reactions, with the main reaction products Amph+Plg (+Zo). Deformation is localized in broad C' and C SB formed by a fine-grained (0.1 - 0.8 μm) mixture of Plg+Amph (+Zo). The onset of mineral reactions in the 700°C experiments shows that reaction kinetics and diffusional mass transport are fast enough to keep up with the short experimental timescales. While in the 700°C experiments brittle processes kinematically contribute to deformation, fracturing is largely absent at 800°C. Diffusive mass transfer dominates. The very small grain size within SB favours a grain size sensitive deformation mechanism. Due to the presence of water (and relatively high supported stresses), dissolution-precipitation creep is interpreted to be the dominant strain accommodating mechanism. From the change of Amph coronas around Px clasts with strain, we can determine that Amph is re-dissolved at high stress sites while growing in low stress sites, showing the ability of Amph to

The Afar rift zone deformation dynamics retrieved through phase and amplitude SAR data

NASA Astrophysics Data System (ADS)

Casu, F.; Pagli, C.; Paglia, L.; Wang, H.; Wright, T. J.; Lanari, R.

2011-12-01

The Dabbahu rift segment of the Afar depression has been active since 2005 when a 2.5 km3 dyke intrusion and hundreds of earthquakes marked the onset a rifting episode which continues to date. Since 2003, the Afar depression has been repeatedly imaged by the ENVISAT satellite, generating a large SAR archive which allow us to study the ongoing deformation processes and the dynamics of magma movements. We combine sets of small baseline interferograms through the advanced DInSAR algorithm referred to as Small BAseline Subset (SBAS), and we generate both ground deformation maps and time series along the satellite Line-Of-Sight (LOS), with accuracies on the order of 5 mm. The main limitation of DInSAR applications is that large and rapid deformations, such as those caused by dyke intrusions and eruptions in Afar, cannot be fully measured. The phase information often degrades and some areas of the interferograms are affected by high fringe rates, leading to difficulties in the phase unwrapping, and/or to complete loss of coherence due to significant misregistration errors. This limitation can be overcome by exploiting the SAR image amplitude information instead of the phase, and by calculating the Pixel-Offset (PO) field of a given SAR image pair, for both range and azimuth directions. Moreover, after computing the POs for each image pair, it is possible to combine them, following the same rationale of the SBAS technique, to finally retrieve the offset-based deformation time series. Such technique, named PO-SBAS, permits to retrieve the deformation field in areas affected by very large displacements at an accuracy that, for ENVISAT data, correspond to 30cm and 15 cm for the range and azimuth, respectively. In this work, we study the Afar rift region deformations by using both the phase and amplitude information of several sets of SAR images acquired from ascending and descending ENVISAT tracks. In particular, we use the phase information to construct dense and accurate

Study of the active deformation of Mitidja (Tell Atlas, Algeria) by GPS

NASA Astrophysics Data System (ADS)

Bacha, Wahab; Masson, Frederic; Yelles-Chaouche, Abdelkrim; Lammali, Kamel; Bellik, Amar; Hamai, Lamine

2013-04-01

A network was created in the Mitidja region around the capital Algiers (Algeria). It has been established to study the deformation of the region and the slow operation of flaws in it. The network was installed by a distribution of GPS stations according to structural domains existing in the region. Twelve bases spread across the study area, have been installed. The measurements were acquired by performing four measurement campaigns in 2006, 2007, 2009 and 2010, with sessions over a month of action. This work allowed the installation of a geodetic network of regional monitoring by methodology GPS in the zone of Mitidja (Tellian Atlas, Algeria). Four observation campaigns were carried out on this area with session's superiors in one month of measurements. The treatment was carried out with software GAMIT-GLOBK, the network is attached to several world stations IGS treated between 2000-2010, indexed in a precise frame of reference ITRF05. The results presented in this memory show a deformation in shortening ≤ 0.5 mm/an in the plain of Mitidja and the surrounding Solid masses.

Deformation of second and third quantization

NASA Astrophysics Data System (ADS)

Faizal, Mir

2015-03-01

In this paper, we will deform the second and third quantized theories by deforming the canonical commutation relations in such a way that they become consistent with the generalized uncertainty principle. Thus, we will first deform the second quantized commutator and obtain a deformed version of the Wheeler-DeWitt equation. Then we will further deform the third quantized theory by deforming the third quantized canonical commutation relation. This way we will obtain a deformed version of the third quantized theory for the multiverse.

a New Approach for Subway Tunnel Deformation Monitoring: High-Resolution Terrestrial Laser Scanning

NASA Astrophysics Data System (ADS)

Li, J.; Wan, Y.; Gao, X.

2012-07-01

With the improvement of the accuracy and efficiency of laser scanning technology, high-resolution terrestrial laser scanning (TLS) technology can obtain high precise points-cloud and density distribution and can be applied to high-precision deformation monitoring of subway tunnels and high-speed railway bridges and other fields. In this paper, a new approach using a points-cloud segmentation method based on vectors of neighbor points and surface fitting method based on moving least squares was proposed and applied to subway tunnel deformation monitoring in Tianjin combined with a new high-resolution terrestrial laser scanner (Riegl VZ-400). There were three main procedures. Firstly, a points-cloud consisted of several scanning was registered by linearized iterative least squares approach to improve the accuracy of registration, and several control points were acquired by total stations (TS) and then adjusted. Secondly, the registered points-cloud was resampled and segmented based on vectors of neighbor points to select suitable points. Thirdly, the selected points were used to fit the subway tunnel surface with moving least squares algorithm. Then a series of parallel sections obtained from temporal series of fitting tunnel surfaces were compared to analysis the deformation. Finally, the results of the approach in z direction were compared with the fiber optical displacement sensor approach and the results in x, y directions were compared with TS respectively, and comparison results showed the accuracy errors of x, y, z directions were respectively about 1.5 mm, 2 mm, 1 mm. Therefore the new approach using high-resolution TLS can meet the demand of subway tunnel deformation monitoring.

Towards a decision support system for hand dermatology.

PubMed

Mazzola, Luca; Cavazzina, Alice; Pinciroli, Francesco; Bonacina, Stefano; Pigatto, Paolo; Ayala, Fabio; De Pità, Ornella; Marceglia, Sara

2014-01-01

The complexity of the medical diagnosis is faced by practitioners relying mainly on their experiences. This can be acquired during daily practices and on-the-job training. Given the complexity and extensiveness of the subject, supporting tools that include knowledge extracted by highly specialized practitioners can be valuable. In the present work, a Decision Support System (DSS) for hand dermatology was developed based on data coming from a Visit Report Form (VRF). Using a Bayesian approach and factors significance difference over the population average for the case, we demonstrated the potentiality of creating an enhanced VRF that include a diagnoses distribution probability based on the DSS rules applied for the specific patient situation.

Stiff Hands

MedlinePlus

... Stiff Hands Find a hand surgeon near you. Videos Figures Figure 1: Hand splint to help straighten ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

Hand Fractures

MedlinePlus

... Hand Fractures Find a hand surgeon near you. Videos Hand Fractures Close Popup Figures Figure 1 - Examples ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

Computed tomography in children with community-acquired pneumonia.

PubMed

Andronikou, Savvas; Goussard, Pierre; Sorantin, Erich

2017-10-01

Diagnostic imaging plays a significant role in both the diagnosis and treatment of complications of pneumonia in children and chest radiography is the imaging modality of choice. Computed tomography (CT) on the other hand, is not currently a first-line imaging tool for children with suspected uncomplicated community-acquired pneumonia and is largely reserved for when complications of pneumonia are suspected or there is difficulty in differentiating pneumonia from other pathology. This review outlines the situations where CT needs to be considered in children with pneumonia, describes the imaging features of the parenchymal and pleural complications of pneumonia, discusses how CT may have a wider role in developing countries where human immunodeficiency virus (HIV) and tuberculosis are prevalent, makes note of the role of CT scanning for identifying missed foreign body aspiration and, lastly, addresses radiation concerns.

Deformations of the Almheiri-Polchinski model

NASA Astrophysics Data System (ADS)

Kyono, Hideki; Okumura, Suguru; Yoshida, Kentaroh

2017-03-01

We study deformations of the Almheiri-Polchinski (AP) model by employing the Yang-Baxter deformation technique. The general deformed AdS2 metric becomes a solution of a deformed AP model. In particular, the dilaton potential is deformed from a simple quadratic form to a hyperbolic function-type potential similarly to integrable deformations. A specific solution is a deformed black hole solution. Because the deformation makes the spacetime structure around the boundary change drastically and a new naked singularity appears, the holographic interpretation is far from trivial. The Hawking temperature is the same as the undeformed case but the Bekenstein-Hawking entropy is modified due to the deformation. This entropy can also be reproduced by evaluating the renormalized stress tensor with an appropriate counter-term on the regularized screen close to the singularity.

Crustal deformations in the Central Mediterranean derived from the WHAT A CAT GPS project.

NASA Astrophysics Data System (ADS)

Kaniuth, K.; Drewes, H.; Stuber, K.; Tremel, H.; Kahler, H.-G.; Peter, Y.; Zerbini, S.; Tonti, G.; Veis, G.; Fagard, H.

1999-03-01

The West Hellenic Arc Tectonics and Calabrian Arc Tectonics (WHAT A CAT) project aimes at monitoring crustal deformations in the Central Mediterranean by repeated GPS campaigns. The data set acquired so far is rather heterogeneous in terms of availability of GPS satellites, performance of the involved receiver systems and quality of the satellites' orbits. The paper presents the velocity estimates achieved using a modified version of the Bernese GPS software. Main characteristic of the solution strategy is the definition of station velocity parameters already on theobservation equation level.

Generalized Ehrenfest Relations, Deformation Quantization, and the Geometry of Inter-model Reduction

NASA Astrophysics Data System (ADS)

Rosaler, Joshua

2018-03-01

This study attempts to spell out more explicitly than has been done previously the connection between two types of formal correspondence that arise in the study of quantum-classical relations: one the one hand, deformation quantization and the associated continuity between quantum and classical algebras of observables in the limit \\hbar → 0, and, on the other, a certain generalization of Ehrenfest's Theorem and the result that expectation values of position and momentum evolve approximately classically for narrow wave packet states. While deformation quantization establishes a direct continuity between the abstract algebras of quantum and classical observables, the latter result makes in-eliminable reference to the quantum and classical state spaces on which these structures act—specifically, via restriction to narrow wave packet states. Here, we describe a certain geometrical re-formulation and extension of the result that expectation values evolve approximately classically for narrow wave packet states, which relies essentially on the postulates of deformation quantization, but describes a relationship between the actions of quantum and classical algebras and groups over their respective state spaces that is non-trivially distinct from deformation quantization. The goals of the discussion are partly pedagogical in that it aims to provide a clear, explicit synthesis of known results; however, the particular synthesis offered aspires to some novelty in its emphasis on a certain general type of mathematical and physical relationship between the state spaces of different models that represent the same physical system, and in the explicitness with which it details the above-mentioned connection between quantum and classical models.

Assessing physical function in adult acquired major upper-limb amputees by combining the Disabilities of the Arm, Shoulder and Hand (DASH) Outcome Questionnaire and clinical examination.

PubMed

Ostlie, Kristin; Franklin, Rosemary J; Skjeldal, Ola H; Skrondal, Anders; Magnus, Per

2011-10-01

To describe physical function in adult acquired major upper-limb amputees (ULAs) by combining self-assessed arm function and physical measures obtained by clinical examinations; to estimate associations between background factors and self-assessed arm function in ULAs; and to assess whether clinical examination findings may be used to detect reduced arm function in unilateral ULAs. postal questionnaires and clinical examinations. Norwegian ULA population. Clinical examinations performed at 3 clinics. Questionnaires: population-based sample (n=224; 57.4% response rate). Clinical examinations: combined referred sample and convenience sample of questionnaire responders (n=70; 83.3% of those invited). SURVEY inclusion criteria: adult acquired major upper-limb amputation, resident in Norway, mastering of spoken and written Norwegian. Not applicable. The Disabilities of the Arm, Shoulder and Hand (DASH) Outcome Questionnaire, and clinical examination of joint motion and muscle strength with and without prostheses. Mean DASH score was 22.7 (95% confidence interval [CI], 20.3-25.0); in bilateral amputees, 35.7 (95% CI, 23.0-48.4); and in unilateral amputees, 22.1 (95% CI, 19.8-24.5). A lower unilateral DASH score (better function) was associated with paid employment (vs not in paid employment: adjusted regression coefficient [aB]=-5.40, P=.033; vs students: aB=-13.88, P=.022), increasing postamputation time (aB=-.27, P=.001), and Norwegian ethnicity (aB=-14.45, P<.001). At clinical examination, we found a high frequency of impaired neck mobility and varying frequencies of impaired joint motion and strength at the shoulder, elbow, and forearm level. Prosthesis wear was associated with impaired joint motion in all upper-limb joints (P<.006) and with reduced shoulder abduction strength (P=.002). Impaired without-prosthesis joint motion in shoulder flexion (ipsilateral: aB=12.19, P=.001) and shoulder abduction (ipsilateral: aB=12.01, P=.005; contralateral: aB=28.82, P=.004

Cyclic Deformation of Ultra-Fine Grained Commercial Purity Aluminum Processed by Accumulative Roll-Bonding

PubMed Central

Kwan, Charles C.F.; Wang, Zhirui

2013-01-01

Accumulative Roll-Bonding (ARB) is one of the more recently developed techniques capable of producing bulk ultra-fine grained (ufg) metals. There are still many aspects of the behavior of ufg metals that lacks an in-depth understanding, such as a generalized view of the factors that govern the cyclic deformation mechanism(s). This study aims to advance the understanding of the cyclic deformation behavior of ufg metals through the systematic investigation of ARB processed aluminum upon cyclic loading. It was found that the cyclic softening response often reported for ufg metals is largely influenced by the microstructure stability as the cyclic softening response is facilitated by grain coarsening which becomes inhibited with highly stable microstructure. On one hand, shear bands resembling braids of dislocations trespassing multiple grains have been observed to operate for the accommodation of the imposed cyclic strain in cases where grain coarsening is largely restricted. On the other hand, it was found that the microstructure stability can be overcome at higher applied cyclic plastic strain levels, leading to grain coarsening and thus a cyclic softening response. The findings in this study have further confirmed that the cyclic softening behavior found in many ufg metals, which may be detrimental in practical applications, can be inhibited by improvements in the microstructure stability. PMID:28811446

Hand Washing

MedlinePlus

... study, only 58% of female and 48% of male middle- and high-school students washed their hands after using the bathroom. Yuck! How to Wash Your Hands Correctly There's a right way to wash your hands. Follow these simple ...

Surface Deformation in Quetta Valley, Balochistan, Pakistan

NASA Astrophysics Data System (ADS)

Huang, J.; Shuhab, K.; Wulamu, A.; Crupa, W.; Khan, A. S.; Kakar, D. M.; Kasi, A.

2015-12-01

In February 2011, several ground fissures up to ~1.8 km in length appeared in the Quetta Valley, Balochsitan, Pakistan. It is not clear what caused the sudden occurrence of these fissures. The region is tectonically active and bounded to the west by several regional strike-slip faults including the north-south striking left-lateral Chaman fault system that slips at ~10 mm per year. Several large earthquakes have occurred recently in this area, one fatal 6.4 magnitude (Mw) earthquake occurred on October 28th, 2008. Some parts of Quetta Valley are subsiding; GPS data from two stations in Quetta that span mid-2006 - 2009 recorded subsidence rates of ~10 cm per year. Although subsidence in urban areas is generally attributed to groundwater depletion, it is not clear whether ground fissures are caused by water withdrawal or related to tectonics of the region. This study is designed to quantify and assess the source of surface deformation in Quetta Valley using InSAR, GPS, seismic and earthquake centroid moment tensor data. To detect and map the spatial-temporal features of the processes that led to the surface deformation, we used two time series, i.e., 15 European Remote Sensing (ERS-1/2) satellite images from 1992 - 1999 and 27 ENVISAT images spanning 2003 - 2010. A Differential Interferometric Synthetic Aperture Radar (DInSAR) Small Baseline Subset (SBAS) technique was used to investigate surface deformation. Eleven continuous-GPS stations within the InSAR antenna footprint were compared with the InSAR time series for quality control. Preliminary InSAR results revealed that the areas in and around the fissures are subsiding at 5 cm per year. Five seismic lines totaling ~60 km, acquired in 2003, were used to interpret faults beneath Holocene alluvium in the Quetta Valley. One of the blind faults is a north-south striking thrust fault mapped north into the Takatu range. However, a focal mechanism for the 2008 earthquake in this region indicated northwest

Hand hygiene compliance by health care workers at a teaching hospital, Kingston, Jamaica.

PubMed

Nicholson, Alison M; Tennant, Ingrid A; Martin, Allie C; Ehikhametalor, Kelvin; Reynolds, Glendee; Thoms-Rodriguez, Camille-Ann; Nagassar, Rajeev; Hoilett, Tena-Kim; Allen, Roxanne; Redwood, Tahira; Crandon, Ivor

2016-10-31

Consistent practice of hand hygiene (HH) has been shown to reduce the incidence and spread of hospital acquired infections. The objectives of this study were to determine the level of compliance and possible factors affecting compliance with HH practices among HCWs at a teaching hospital in Kingston, Jamaica. A prospective observational study was undertaken at the University Hospital of the West Indies (UHWI) over a two weeks period. Trained, validated observers identified opportunities for hand hygiene as defined by the WHO "Five Hand Hygiene Moments" and recorded whether appropriate hand hygiene actions were taken or missed. Observations were covert to prevent the observer's presence influencing the behaviour of the healthcare workers (HCWs) and targeted areas included the intensive care units (ICUs), surgical wards and surgical outpatient departments. A ward infrastructure survey was also done. Data were entered and analysed using SPSS version 16 for Windows. Chi-square analysis using Pearson's formula was used to test associations between 'exposure' factors and the outcome 'compliance'. A total of 270 hand hygiene opportunities were observed and the overall compliance rate was 38.9%. No differences were observed between the various types of HCWs or seniority. HCWs were more likely to perform hand hygiene if the indication was 'after' rather than 'before' patient contact (p = 0.001). This study underscores the need for improvement in HH practices among HCWs in a teaching hospital. Health education with particular attention to the need for HH prior to physical contact with patients is indicated.

An evaluation of hospital hand hygiene practice and glove use in Hong Kong.

PubMed

Chau, Janita P-C; Thompson, David R; Twinn, Sheila; Lee, Diana T F; Pang, Sharon W M

2011-05-01

To identify omissions in hand hygiene practice and glove use among hospital workers in Hong Kong. Hospital-acquired infection is the commonest complication affecting hospitalised patients. Even though research evidence suggests that hand hygiene and proper glove use are the most important ways to prevent the spread of disease and infection, compliance with both are reported to be unacceptably low. An observational study of hospital workers in one acute and two convalescence and rehabilitation hospitals in Hong Kong was conducted. The participating clinical areas included the medical and surgical wards, accident and emergency department and intensive care unit. Hand hygiene practice and glove use amongst 206 hospital health and support workers, stratified according to years of working experience, were observed. The number of observed episodes for hand hygiene was 1037 and for glove use 304. Compliance with hand hygiene was 74.7% and with glove use 72.4%. In approximately two-third of episodes, participants washed their hands after each patient contact; though, 78.5% failed to rub their hands together vigorously for at least 15 seconds. The major break in compliance with glove use was failure to change gloves between procedures on the same patient. In 28.6% of observed glove use episodes, participants did not wear gloves during procedures that exposed them to blood, body fluids, excretion, non-intact skin or mucous membranes. Significant differences in performance scores on antiseptic hand rub were found between the two types of hospital and on glove use between the three groups of work experience: ≤ 5, 6-10, >10 years. Education and reinforcement of proper hand hygiene practice and glove use among hospital health and support workers is needed. © 2011 Blackwell Publishing Ltd.

a Research on Monitoring Surface Deformation and Relationships with Surface Parameters in Qinghai Tibetan Plateau Permafrost

NASA Astrophysics Data System (ADS)

Mi, S. J.; Li, Y. T.; Wang, F.; Li, L.; Ge, Y.; Luo, L.; Zhang, C. L.; Chen, J. B.

2017-09-01

The Qinghai Tibetan Plateau permafrost has been the largest permafrost region in middle-low latitude in the world for its high altitude. For the large area permafrost, especially surface deformation brought by it, have serious influence on the road engineering, road maintaining and regional economic development. Consequently, it is essential to monitor the surface deformation and study factors that influent it. We monitored an area named Wudaoliang from July 25, 2015 to June 1, 2016 and 15 Sentinel images were obtained during this time. The area we chose is about 35 kilometers long and 2 kilometers wide, and the national road 109 of China passes through the area. The traditional PS-INSAR (Persistent Scatterer Interferometric Synthetic Aperture Radar) method is not suitable because less historical images in the research area and leading to the number of PS (Persistent Scatterer) points is not enough to obtain accurate deformation results. Therefore, in this paper, we used another method which named QUASI-PSInSAR (QUASI Persistent Scatterer Interferometric Synthetic Aperture Radar) to acquire deformation for it has the advantage to weaken or eliminate the effects of spatial and temporal correlation, which has proved by other scholar. After processing 15 images in the SARproz software, we got the conclusions that, 1) the biggest deformation velocity in the whole area was about 127.9mm/year and about 109.3 mm/year in the road; 2) apparent deformation which have surface deformation more than 30mm/year was about 1.7Km in the road. Meanwhile, soil moisture(SM), Land surface temperature (LST) and surface water(SW), which are primary parameters of the land surface over the same time were reversed by using Sentinel data, Landsat data and ZY-3 data, respectively. After analyzing SM, LST , SW and deformation, we obtained that wet areas which had bigger SM, lower LST and more SW, had greater percentage of severe deformation than arid areas; besides, deformation pattern were

Deformation Invariant Attribute Vector for Deformable Registration of Longitudinal Brain MR Images

PubMed Central

Li, Gang; Guo, Lei; Liu, Tianming

2009-01-01

This paper presents a novel approach to define deformation invariant attribute vector (DIAV) for each voxel in 3D brain image for the purpose of anatomic correspondence detection. The DIAV method is validated by using synthesized deformation in 3D brain MRI images. Both theoretic analysis and experimental studies demonstrate that the proposed DIAV is invariant to general nonlinear deformation. Moreover, our experimental results show that the DIAV is able to capture rich anatomic information around the voxels and exhibit strong discriminative ability. The DIAV has been integrated into a deformable registration algorithm for longitudinal brain MR images, and the results on both simulated and real brain images are provided to demonstrate the good performance of the proposed registration algorithm based on matching of DIAVs. PMID:19369031

Nearly associative deformation quantization

NASA Astrophysics Data System (ADS)

Vassilevich, Dmitri; Oliveira, Fernando Martins Costa

2018-04-01

We study several classes of non-associative algebras as possible candidates for deformation quantization in the direction of a Poisson bracket that does not satisfy Jacobi identities. We show that in fact alternative deformation quantization algebras require the Jacobi identities on the Poisson bracket and, under very general assumptions, are associative. At the same time, flexible deformation quantization algebras exist for any Poisson bracket.

Strategy and your stronger hand.

PubMed

Moore, Geoffrey A

2005-12-01

There are two kinds of businesses in the world, says the author. Knowing what they are--and which one your company is--will guide you to the right strategic moves. One kind includes businesses that compete on a complex-systems model. These companies have large enterprises as their primary customers. They seek to grow a customer base in the thousands, with no more than a handful of transactions per customer per year (indeed, in some years there may be none), and the average price per transaction ranges from six to seven figures. In this model, 1,000 enterprises each paying dollar 1 million per year would generate dollar 1 billion in annual revenue. The other kind of business competes on a volume-operations model. Here, vendors seek to acquire millions of customers, with tens or even hundreds of transactions per customer per year, at an average price of relatively few dollars per transaction. Under this model, it would take 10 million customers each spending dollar 8 per month to generate nearly dollar 1 billion in revenue. An examination of both models shows that they could not be further apart in their approach to every step along the classic value chain. The problem, though, is that companies in one camp often attempt to create new value by venturing into the other. In doing so, they fail to realize how their managerial habits have been shaped by the model they've grown up with. By analogy, they have a "handedness"--the equivalent of a person's right- or left-hand dominance--that makes them as adroit in one mode as they are awkward in the other. Unless you are in an industry whose structure forces you to attempt ambidexterity (in which case, special efforts are required to manage the inevitable dropped balls), you'll be far more successful making moves that favor your stronger hand.

Projection Moire Interferometry for Rotorcraft Applications: Deformation Measurements of Active Twist Rotor Blades

NASA Technical Reports Server (NTRS)

Fleming, Gary A.; Soto, Hector L.; South, Bruce W.

2002-01-01

Projection Moire Interferometry (PMI) has been used during wind tunnel tests to obtain azimuthally dependent blade bending and twist measurements for a 4-bladed Active Twist Rotor (ATR) system in simulated forward flight. The ATR concept offers a means to reduce rotor vibratory loads and noise by using piezoelectric active fiber composite actuators embedded in the blade structure to twist each blade as they rotate throughout the rotor azimuth. The twist imparted on the blades for blade control causes significant changes in blade loading, resulting in complex blade deformation consisting of coupled bending and twist. Measurement of this blade deformation is critical in understanding the overall behavior of the ATR system and the physical mechanisms causing the reduction in rotor loads and noise. PMI is a non-contacting, video-based optical measurement technique capable of obtaining spatially continuous structural deformation measurements over the entire object surface within the PMI system field-of-view. When applied to rotorcraft testing, PMI can be used to measure the azimuth-dependent blade bending and twist along the full span of the rotor blade. This paper presents the PMI technique as applied to rotorcraft testing, and provides results obtained during the ATR tests demonstrating the PMI system performance. PMI measurements acquired at select blade actuation conditions generating minimum and maximum rotor loads are provided to explore the interrelationship between rotor loads, blade bending, and twist.

Inspections of hand washing supplies and hand sanitizer in public schools.

PubMed

Ramos, Mary M; Blea, Mary; Trujillo, Rebecca; Greenberg, Cynthia

2010-10-01

Hand washing and hand antisepsis are proven infection control measures in the school setting, yet barriers such as lack of soap, paper towels, and hand sanitizer can hinder compliance. This pilot study measured the prevalence of hand cleaning supplies in public schools. Ten school districts (93 schools) participated in school nurse inspections. In November 2008, 90 schools (97%) reported their inspection results. Among 697 total bathrooms, 88.8% had soap and 91.7% had paper towels or hand dryers. Hand sanitizer was reported in 1.2% of bathrooms and 15.2% of cafeterias. No difference was observed between boys' and girls' bathrooms, or primary and secondary schools, in the prevalence of soap or paper towels/hand dryers. Hand washing supplies were generally available in public school bathrooms. Alcohol-based hand sanitizer in school bathrooms was reported occasionally and should be discouraged. Hand sanitizer in a supervised setting, the school cafeteria, was not often reported and should be promoted.

Moisturizing alcohol hand gels for surgical hand preparation.

PubMed

Jones, R D; Jampani, H; Mulberry, G; Rizer, R L

2000-03-01

With the use of novel formulary technology, unique moisturizing hand gels have been developed that offer significant advantages in perioperative and other health care settings. These advantages include the time-saving capabilities of a waterless formulation, the persistence and effectiveness of a surgical scrub, and the moisturization and protective properties of a lotion. Extensive laboratory and clinical studies, involving in vivo antimicrobial activity against resident and transient flora, skin moisturization on normal and dry skin, and compatibility with latex gloves, have supported these advantages. Nondrying alcohol hand gels can be used for antiseptic hand washing, hand scrubs between procedures (i.e., reentry scrubs), brushless surgical scrubs, moisturizers, and glove-donning aids.

Acquired color vision deficiency.

PubMed

Simunovic, Matthew P

2016-01-01

Acquired color vision deficiency occurs as the result of ocular, neurologic, or systemic disease. A wide array of conditions may affect color vision, ranging from diseases of the ocular media through to pathology of the visual cortex. Traditionally, acquired color vision deficiency is considered a separate entity from congenital color vision deficiency, although emerging clinical and molecular genetic data would suggest a degree of overlap. We review the pathophysiology of acquired color vision deficiency, the data on its prevalence, theories for the preponderance of acquired S-mechanism (or tritan) deficiency, and discuss tests of color vision. We also briefly review the types of color vision deficiencies encountered in ocular disease, with an emphasis placed on larger or more detailed clinical investigations. Copyright © 2016 Elsevier Inc. All rights reserved.

Post Deformation at Room and Cryogenic Temperature Cooling Media on Severely Deformed 1050-Aluminum

NASA Astrophysics Data System (ADS)

Khorrami, M. Sarkari; Kazeminezhad, M.

2018-03-01

The annealed 1050-aluminum sheets were initially subjected to the severe plastic deformation through two passes of constrained groove pressing (CGP) process. The obtained specimens were post-deformed by friction stir processing at room and cryogenic temperature cooling media. The microstructure evolutions during mentioned processes in terms of grain structure, misorientation distribution, and grain orientation spread (GOS) were characterized using electron backscattered diffraction. The annealed sample contained a large number of "recrystallized" grains and relatively large fraction (78%) of high-angle grain boundaries (HAGBs). When CGP process was applied on the annealed specimen, the elongated grains with interior substructure were developed, which was responsible for the formation of 80% low-angle grain boundaries. The GOS map of the severely deformed specimen manifested the formation of 43% "distorted" and 51% "substructured" grains. The post deformation of severely deformed aluminum at room temperature led to the increase in the fraction of HAGBs from 20 to 60%. Also, it gave rise to the formation of "recrystallized" grains with the average size of 13 μm, which were coarser than the grains predicted by Zener-Hollomon parameter. This was attributed to the occurrence of appreciable grain growth during post deformation. In the case of post deformation at cryogenic temperature cooling medium, the grain size was decreased, which was in well agreement with the predicted grain size. The cumulative distribution of misorientation was the same for both processing routes. Mechanical properties characterizations in terms of nano-indentation and tensile tests revealed that the post deformation process led to the reduction in hardness, yield stress, and ultimate tensile strength of the severely deformed aluminum.

Nuclear Deformation at Finite Temperature

NASA Astrophysics Data System (ADS)

Alhassid, Y.; Gilbreth, C. N.; Bertsch, G. F.

2014-12-01

Deformation, a key concept in our understanding of heavy nuclei, is based on a mean-field description that breaks the rotational invariance of the nuclear many-body Hamiltonian. We present a method to analyze nuclear deformations at finite temperature in a framework that preserves rotational invariance. The auxiliary-field Monte Carlo method is used to generate a statistical ensemble and calculate the probability distribution associated with the quadrupole operator. Applying the technique to nuclei in the rare-earth region, we identify model-independent signatures of deformation and find that deformation effects persist to temperatures higher than the spherical-to-deformed shape phase-transition temperature of mean-field theory.

Acquired platelet function defect

MedlinePlus

... Some cases cannot be prevented. Alternative Names Acquired qualitative platelet disorders; Acquired disorders of platelet function Images ... Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare ...

Disseminated cryptococcosis and fluconazole resistant oral candidiasis in a patient with acquired immunodeficiency syndrome (AIDS).

PubMed

Kothavade, Rajendra J; Oberai, Chetan M; Valand, Arvind G; Panthaki, Mehroo H

2010-10-28

Disseminated cryptococcosis and recurrent oral candidiasis was presented in a-heterosexual AIDS patient. Candida tropicalis (C.tropicalis) was isolated from the oral pseudomembranous plaques and Cryptococcus neoformans (C. neoformans) was isolated from maculopapular lesions on body parts (face, hands and chest) and body fluids (urine, expectorated sputum, and cerebrospinal fluid). In vitro drug susceptibility testing on the yeast isolates demonstrated resistance to fluconazole acquired by C. tropicalis which was a suggestive possible root cause of recurrent oral candidiasis in this patient.

InSAR observation of seasonal ground surface deformation in permafrost area near Batagay, Siberia

NASA Astrophysics Data System (ADS)

Yanagiya, K.; Furuya, M.

2017-12-01

Thawing of permafrost can lead to ground deformation. Ground deformation has been studied as a serious problem in the Arctic Ocean coastal area such as Russia for a long time, because the deformation causes damage to architectures at these areas. However, there have been no quantitative observation data, and the spatial and temporal distributions have hardly been investigated. On the other hand, by the recently global warming influence, the importance of organic carbon stored in permafrost is pointed out. Although the release of methane gas is confirmed in some thermokarst lakes, it is very difficult to observe the permafrost in a wide area by field study. Instead, it is technically possible to monitor the subsidence and uplift of the ground over the permafrost area, which could potentially make a significant contribution to the monitoring thawing process of permafrost. In this study, we attempted to detect ground deformation signal in permafrost area by remote sensing using interferometric synthetic aperture radar (InSAR). Using the data of two SAR satellites ALOS and ALOS2 launched by JAXA, we observed recent ground deformation from 2007 to 2016. Particularly recent observations of ALOS2 from 2014 to 2016 discovered distant displacements towards the LOS direction in the northeast region from the town of Batagay,Siberia. The diameter of the displacements area covers about 7.7 km. In this study, we considered that this signal is likely to be due to permafrost thawing, we also investigated the seasonal characteristics and looked back ALOS data of this area. In addition, since the high latitude area, observation results include noise due to the ionosphere, so we tried to remove the noise.

Seeing mathematics: perceptual experience and brain activity in acquired synesthesia.

PubMed

Brogaard, Berit; Vanni, Simo; Silvanto, Juha

2013-01-01

We studied the patient JP who has exceptional abilities to draw complex geometrical images by hand and a form of acquired synesthesia for mathematical formulas and objects, which he perceives as geometrical figures. JP sees all smooth curvatures as discrete lines, similarly regardless of scale. We carried out two preliminary investigations to establish the perceptual nature of synesthetic experience and to investigate the neural basis of this phenomenon. In a functional magnetic resonance imaging (fMRI) study, image-inducing formulas produced larger fMRI responses than non-image inducing formulas in the left temporal, parietal and frontal lobes. Thus our main finding is that the activation associated with his experience of complex geometrical images emerging from mathematical formulas is restricted to the left hemisphere.

Cosmetic and Functional Nasal Deformities

MedlinePlus

... nasal complaints. Nasal deformity can be categorized as “cosmetic” or “functional.” Cosmetic deformity of the nose results in a less ... taste , nose bleeds and/or recurrent sinusitis . A cosmetic or functional nasal deformity may occur secondary to ...

Exploding Balloons, Deformed Balls, Strange Reflections and Breaking Rods: Slow Motion Analysis of Selected Hands-On Experiments

ERIC Educational Resources Information Center

Vollmer, Michael; Mollmann, Klaus-Peter

2011-01-01

A selection of hands-on experiments from different fields of physics, which happen too fast for the eye or video cameras to properly observe and analyse the phenomena, is presented. They are recorded and analysed using modern high speed cameras. Two types of cameras were used: the first were rather inexpensive consumer products such as Casio…

Time-series analysis of surface deformation at Brady Hot Springs geothermal field (Nevada) using interferometric synthetic aperture radar

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ali, S. T.; Akerley, J.; Baluyut, E. C.

We analyze interferometric synthetic aperture radar (InSAR) data acquired between 2004 and 2014, by the ERS-2, Envisat, ALOS and TerraSAR-X/TanDEM-X satellite missions to measure and characterize time-dependent deformation at the Brady Hot Springs geothermal field in western Nevada due to extraction of fluids. The long axis of the ~4 km by ~1.5 km elliptical subsiding area coincides with the strike of the dominant normal fault system at Brady. Within this bowl of subsidence, the interference pattern shows several smaller features with length scales of the order of ~1 km. This signature occurs consistently in all of the well-correlated interferometric pairsmore » spanning several months. Results from inverse modeling suggest that the deformation is a result of volumetric contraction in shallow units, no deeper than 600 m, likely associated with damaged regions where fault segments mechanically interact. Such damaged zones are expected to extend downward along steeply dipping fault planes, providing a high permeability conduit to the production wells. Using time series analysis, we test the hypothesis that geothermal production drives the observed deformation. We find a good correlation between the observed deformation rate and the rate of production in the shallow wells. We also explore mechanisms that could potentially cause the observed deformation, including thermal contraction of rock, decline in pore pressure and dissolution of minerals over time.« less

Normal values for myocardial deformation within the right heart measured by feature-tracking cardiovascular magnetic resonance imaging.

PubMed

Liu, Boyang; Dardeer, Ahmed M; Moody, William E; Edwards, Nicola C; Hudsmith, Lucy E; Steeds, Richard P

2018-02-01

Reproducible and repeatable assessment of right heart function is vital for monitoring congenital and acquired heart disease. There is increasing evidence for the additional value of myocardial deformation (strain and strain rate) in determining prognosis. This study aims to determine the reproducibility of deformation analyses in the right heart using cardiovascular magnetic resonance feature tracking (FT-CMR); and to establish normal ranges within an adult population. A cohort of 100 healthy subjects containing 10 males and 10 females from each decade of life between the ages of 20 and 70 without known congenital or acquired cardiovascular disease, hypertension, diabetes, dyslipidaemia or renal, hepatic, haematologic and systemic inflammatory disorders underwent FT-CMR assessment of right ventricular (RV) and right atrial (RA) myocardial strain and strain rate. RV longitudinal strain (Ell) was -21.9±3.24% (FW+S Ell) and -24.2±3.59% (FW-Ell). Peak systolic strain rate (S') was -1.45±0.39s -1 (FW+S) and -1.54±0.41s -1 (FW). Early diastolic strain rate (E') was 1.04±0.26s -1 (FW+S) and 1.04±0.33s -1 (FW). Late diastolic strain rate (A') was 0.94±0.33s -1 (FW+S) and 1.08±0.33s -1 (FW). RA peak strain was -21.1±3.76%. The intra- and inter-observer ICC for RV Ell (FW+S) was 0.92 and 0.80 respectively, while for RA peak strain was 0.92 and 0.89 respectively. Normal values of RV & RA deformation for healthy individuals using FT-CMR are provided with good RV Ell and RA peak strain reproducibility. Strain rate suffered from sub-optimal reproducibility and may not be satisfactory for clinical use. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Hand preference for sending mobile-phone text messages: associations with sex, writing hand, and throwing hand.

PubMed

Lambert, Anthony; Hallett, Charlene

2009-07-01

Hand preference for sending mobile-phone text messages ("texting") and its relationship with hand preference for other activities were investigated in a questionnaire study with 886 participants. Overall rates of both sinistrality and dextrality were reduced for texting, in comparison with other activities, due to the substantial number of individuals who use both hands simultaneously when performing this activity. Because they both involve verbal expression, it was hypothesised that the association between hand preferences for texting and writing might be stronger than the association between either of these tasks and more spatial activities, such as throwing. This prediction was not confirmed, either in the sample as a whole or in a sub-group of individuals who reported writing and throwing with opposite hands. Females were less likely than males to use their left hand when sending text messages. Implications of these findings are discussed, in relation to theoretical views of handedness and in relation to practical aspects of mobile-phone design.

Axial deformity correction in children via distraction osteogenesis.

PubMed

Antoci, Valentin; Ono, Craig M; Antoci, Valentin; Raney, Ellen M

2006-08-01

We performed a retrospective analysis of the results of 62 tibial and 54 femoral lengthenings in 88 consecutive patients. The patients mean age was 13.5 years and mean follow-up was four years. There was a significant difference between metaphyseal (27+/-1.2 days/cm) and diaphyseal (39.4+/-1.7 days/cm), tibial (34+/-1.7 days/cm) and femoral (31+/-1.4 days/cm) lengthening (P<0.05), but no significant difference among the lengthening indexes when treating one-, two-, or three-dimensional deformities, congenital (34+/-2.4 days/cm) and acquired (32+/-1.0 days/cm) limb length discrepancy (LLD) (P>0.05). The lengthening index was 33+/-1.1 days/cm, distraction regenerate length 6+/-0.4 cm, and lengthening percentage 21+/-2.1. The scatter plots of new regenerate length against time and the scatter plots of neurological complication, residual deformities, broken pins, joint contractures, and hypertension rate against lengthening percentage showed a positive linear relationship (r=0.8). We found the correlations between quantitative and qualitative parameters that should help to predict the treatment outcomes. Lengthening index depends on the amount of length gained. Higher length of new bone regenerate leads to a decrease in lengthening index. Expected gain in bone length can aid in estimating the duration of treatment. The lengthening percentage correlates very well with the complication rate and can be used to predict the complication rate.

Validation of model-based deformation correction in image-guided liver surgery via tracked intraoperative ultrasound: preliminary method and results

NASA Astrophysics Data System (ADS)

Clements, Logan W.; Collins, Jarrod A.; Wu, Yifei; Simpson, Amber L.; Jarnagin, William R.; Miga, Michael I.

2015-03-01

Soft tissue deformation represents a significant error source in current surgical navigation systems used for open hepatic procedures. While numerous algorithms have been proposed to rectify the tissue deformation that is encountered during open liver surgery, clinical validation of the proposed methods has been limited to surface based metrics and sub-surface validation has largely been performed via phantom experiments. Tracked intraoperative ultrasound (iUS) provides a means to digitize sub-surface anatomical landmarks during clinical procedures. The proposed method involves the validation of a deformation correction algorithm for open hepatic image-guided surgery systems via sub-surface targets digitized with tracked iUS. Intraoperative surface digitizations were acquired via a laser range scanner and an optically tracked stylus for the purposes of computing the physical-to-image space registration within the guidance system and for use in retrospective deformation correction. Upon completion of surface digitization, the organ was interrogated with a tracked iUS transducer where the iUS images and corresponding tracked locations were recorded. After the procedure, the clinician reviewed the iUS images to delineate contours of anatomical target features for use in the validation procedure. Mean closest point distances between the feature contours delineated in the iUS images and corresponding 3-D anatomical model generated from the preoperative tomograms were computed to quantify the extent to which the deformation correction algorithm improved registration accuracy. The preliminary results for two patients indicate that the deformation correction method resulted in a reduction in target error of approximately 50%.

Coseismic seafloor deformation in the trench region during the Mw8.8 Maule megathrust earthquake.

PubMed

Maksymowicz, A; Chadwell, C D; Ruiz, J; Tréhu, A M; Contreras-Reyes, E; Weinrebe, W; Díaz-Naveas, J; Gibson, J C; Lonsdale, P; Tryon, M D

2017-04-05

The M w 8.8 megathrust earthquake that occurred on 27 February 2010 offshore the Maule region of central Chile triggered a destructive tsunami. Whether the earthquake rupture extended to the shallow part of the plate boundary near the trench remains controversial. The up-dip limit of rupture during large subduction zone earthquakes has important implications for tsunami generation and for the rheological behavior of the sedimentary prism in accretionary margins. However, in general, the slip models derived from tsunami wave modeling and seismological data are poorly constrained by direct seafloor geodetic observations. We difference swath bathymetric data acquired across the trench in 2008, 2011 and 2012 and find ~3-5 m of uplift of the seafloor landward of the deformation front, at the eastern edge of the trench. Modeling suggests this is compatible with slip extending seaward, at least, to within ~6 km of the deformation front. After the M w 9.0 Tohoku-oki earthquake, this result for the Maule earthquake represents only the second time that repeated bathymetric data has been used to detect the deformation following megathrust earthquakes, providing methodological guidelines for this relatively inexpensive way of obtaining seafloor geodetic data across subduction zone.

Evaluation of high-resolution sea ice models on the basis of statistical and scaling properties of Arctic sea ice drift and deformation

NASA Astrophysics Data System (ADS)

Girard, L.; Weiss, J.; Molines, J. M.; Barnier, B.; Bouillon, S.

2009-08-01

Sea ice drift and deformation from models are evaluated on the basis of statistical and scaling properties. These properties are derived from two observation data sets: the RADARSAT Geophysical Processor System (RGPS) and buoy trajectories from the International Arctic Buoy Program (IABP). Two simulations obtained with the Louvain-la-Neuve Ice Model (LIM) coupled to a high-resolution ocean model and a simulation obtained with the Los Alamos Sea Ice Model (CICE) were analyzed. Model ice drift compares well with observations in terms of large-scale velocity field and distributions of velocity fluctuations although a significant bias on the mean ice speed is noted. On the other hand, the statistical properties of ice deformation are not well simulated by the models: (1) The distributions of strain rates are incorrect: RGPS distributions of strain rates are power law tailed, i.e., exhibit "wild randomness," whereas models distributions remain in the Gaussian attraction basin, i.e., exhibit "mild randomness." (2) The models are unable to reproduce the spatial and temporal correlations of the deformation fields: In the observations, ice deformation follows spatial and temporal scaling laws that express the heterogeneity and the intermittency of deformation. These relations do not appear in simulated ice deformation. Mean deformation in models is almost scale independent. The statistical properties of ice deformation are a signature of the ice mechanical behavior. The present work therefore suggests that the mechanical framework currently used by models is inappropriate. A different modeling framework based on elastic interactions could improve the representation of the statistical and scaling properties of ice deformation.

Non-vascularized free toe phalanx transfers in congenital hand deformities--the Great Ormond Street experience.

PubMed

Cavallo, A V; Smith, P J; Morley, S; Morsi, A W

2003-12-01

Many options of varying complexity are available for the management of congenital short digits resulting from aphalangia in symbrachydactyly and constriction ring syndrome. We have used non-vascularized free toe phalanx transfers for these children when a vascularized toe transfer has been contraindicated. We describe our technique and experience with 22 children who underwent a total of 64 transfers of the proximal (35) or middle (29) toe phalanges (average 3 per child). The mean age at initial surgery was 15 months, and the mean follow-up was 5 years. Duration of time until epiphyseal closure could not be determined accurately, but total digital elongation averaged 6mm. Complications of this technique include joint instability, premature epiphyseal closure and, in one patient, infection and graft loss. Donor site deformity was determined according to measured growth deficit and toe function. This technique is a simple option for digital elongation and, if performed in the appropriate age group in short fingered and monodactylous subtypes of symbrachydactyly, has the potential to allow growth and function with minimal donor site deficit.

Modular Hamiltonians for deformed half-spaces and the averaged null energy condition

NASA Astrophysics Data System (ADS)

Faulkner, Thomas; Leigh, Robert G.; Parrikar, Onkar; Wang, Huajia

2016-09-01

We study modular Hamiltonians corresponding to the vacuum state for deformed half-spaces in relativistic quantum field theories on {{R}}^{1,d-1} . We show that in addition to the usual boost generator, there is a contribution to the modular Hamiltonian at first order in the shape deformation, proportional to the integral of the null components of the stress tensor along the Rindler horizon. We use this fact along with monotonicity of relative entropy to prove the averaged null energy condition in Minkowski space-time. This subsequently gives a new proof of the Hofman-Maldacena bounds on the parameters appearing in CFT three-point functions. Our main technical advance involves adapting newly developed perturbative methods for calculating entanglement entropy to the problem at hand. These methods were recently used to prove certain results on the shape dependence of entanglement in CFTs and here we generalize these results to excited states and real time dynamics. We also discuss the AdS/CFT counterpart of this result, making connection with the recently proposed gravitational dual for modular Hamiltonians in holographic theories.

Deformable templates guided discriminative models for robust 3D brain MRI segmentation.

PubMed

Liu, Cheng-Yi; Iglesias, Juan Eugenio; Tu, Zhuowen

2013-10-01

Automatically segmenting anatomical structures from 3D brain MRI images is an important task in neuroimaging. One major challenge is to design and learn effective image models accounting for the large variability in anatomy and data acquisition protocols. A deformable template is a type of generative model that attempts to explicitly match an input image with a template (atlas), and thus, they are robust against global intensity changes. On the other hand, discriminative models combine local image features to capture complex image patterns. In this paper, we propose a robust brain image segmentation algorithm that fuses together deformable templates and informative features. It takes advantage of the adaptation capability of the generative model and the classification power of the discriminative models. The proposed algorithm achieves both robustness and efficiency, and can be used to segment brain MRI images with large anatomical variations. We perform an extensive experimental study on four datasets of T1-weighted brain MRI data from different sources (1,082 MRI scans in total) and observe consistent improvement over the state-of-the-art systems.

Deformation of crowns during cementation.

PubMed

Wilson, P R; Goodkind, R J; Delong, R; Sakaguchi, R

1990-11-01

Deformation of crowns during cementation was investigated by a simple loading system of defined crowns with silicone fluids as cements. Deformation of the crowns was measured by long stain gauges that encircled the cervical margins. Die spacing was simulated by etching the die. Venting was simulated by removing a small screw. Deformation of the crowns was decreased by decreasing the viscosity of fluid, increasing the thickness of the crowns, and venting. Etching the die decreased the seating times of the crowns, but did not alter the level of deformation. Terminal cementation with zinc phosphate cement confirmed the presence of crown deformation during cementation. The results have consequences for bonded and all-ceramic crowns, and explain several clinical phenomena. It is suggested that low viscosity cements, low seating forces, and die spacing be used to decrease the deformation of crowns during seating. The importance of passive fitting of the crown to the tooth is stressed.

Dealing with difficult deformations: construction of a knowledge-based deformation atlas

NASA Astrophysics Data System (ADS)

Thorup, S. S.; Darvann, T. A.; Hermann, N. V.; Larsen, P.; Ólafsdóttir, H.; Paulsen, R. R.; Kane, A. A.; Govier, D.; Lo, L.-J.; Kreiborg, S.; Larsen, R.

2010-03-01

Twenty-three Taiwanese infants with unilateral cleft lip and palate (UCLP) were CT-scanned before lip repair at the age of 3 months, and again after lip repair at the age of 12 months. In order to evaluate the surgical result, detailed point correspondence between pre- and post-surgical images was needed. We have previously demonstrated that non-rigid registration using B-splines is able to provide automated determination of point correspondences in populations of infants without cleft lip. However, this type of registration fails when applied to the task of determining the complex deformation from before to after lip closure in infants with UCLP. The purpose of the present work was to show that use of prior information about typical deformations due to lip closure, through the construction of a knowledge-based atlas of deformations, could overcome the problem. Initially, mean volumes (atlases) for the pre- and post-surgical populations, respectively, were automatically constructed by non-rigid registration. An expert placed corresponding landmarks in the cleft area in the two atlases; this provided prior information used to build a knowledge-based deformation atlas. We model the change from pre- to post-surgery using thin-plate spline warping. The registration results are convincing and represent a first move towards an automatic registration method for dealing with difficult deformations due to this type of surgery.

Foldover-free shape deformation for biomedicine.

PubMed

Yu, Hongchuan; Zhang, Jian J; Lee, Tong-Yee

2014-04-01

Shape deformation as a fundamental geometric operation underpins a wide range of applications, from geometric modelling, medical imaging to biomechanics. In medical imaging, for example, to quantify the difference between two corresponding images, 2D or 3D, one needs to find the deformation between both images. However, such deformations, particularly deforming complex volume datasets, are prone to the problem of foldover, i.e. during deformation, the required property of one-to-one mapping no longer holds for some points. Despite numerous research efforts, the construction of a mathematically robust foldover-free solution subject to positional constraints remains open. In this paper, we address this challenge by developing a radial basis function-based deformation method. In particular we formulate an effective iterative mechanism which ensures the foldover-free property is satisfied all the time. The experimental results suggest that the resulting deformations meet the internal positional constraints. In addition to radial basis functions, this iterative mechanism can also be incorporated into other deformation approaches, e.g. B-spline based FFDs, to develop different deformable approaches for various applications. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

Performance of 12 DIR algorithms in low-contrast regions for mass and density conserving deformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yeo, U. J.; Supple, J. R.; Franich, R. D.

2013-10-15

Purpose: Deformable image registration (DIR) has become a key tool for adaptive radiotherapy to account for inter- and intrafraction organ deformation. Of contemporary interest, the application to deformable dose accumulation requires accurate deformation even in low contrast regions where dose gradients may exist within near-uniform tissues. One expects high-contrast features to generally be deformed more accurately by DIR algorithms. The authors systematically assess the accuracy of 12 DIR algorithms and quantitatively examine, in particular, low-contrast regions, where accuracy has not previously been established.Methods: This work investigates DIR algorithms in three dimensions using deformable gel (DEFGEL) [U. J. Yeo, M. L.more » Taylor, L. Dunn, R. L. Smith, T. Kron, and R. D. Franich, “A novel methodology for 3D deformable dosimetry,” Med. Phys. 39, 2203–2213 (2012)], for application to mass- and density-conserving deformations. CT images of DEFGEL phantoms with 16 fiducial markers (FMs) implanted were acquired in deformed and undeformed states for three different representative deformation geometries. Nonrigid image registration was performed using 12 common algorithms in the public domain. The optimum parameter setup was identified for each algorithm and each was tested for deformation accuracy in three scenarios: (I) original images of the DEFGEL with 16 FMs; (II) images with eight of the FMs mathematically erased; and (III) images with all FMs mathematically erased. The deformation vector fields obtained for scenarios II and III were then applied to the original images containing all 16 FMs. The locations of the FMs estimated by the algorithms were compared to actual locations determined by CT imaging. The accuracy of the algorithms was assessed by evaluation of three-dimensional vectors between true marker locations and predicted marker locations.Results: The mean magnitude of 16 error vectors per sample ranged from 0.3 to 3.7, 1.0 to 6.3, and 1

Removal of daytime thermal deformations in the GBT active surface via out-of-focus holography

NASA Astrophysics Data System (ADS)

Hunter, T. R.; Mello, M.; Nikolic, B.; Mason, B.; Schwab, F.; Ghigo, F.; Dicker, S.

2009-01-01

The 100-m diameter Green Bank Telescope (GBT) was built with an active surface of 2209 actuators in order to achieve and maintain an accurate paraboloidal shape. While much of the large-scale gravitational deformation of the surface can be described by a finite element model, a significant uncompensated gravitational deformation exists. In recent years, the elevation-dependence of this residual deformation has been successfully measured during benign nighttime conditions using the out-of-focus (OOF) holography technique (Nikolic et al, 2007, A&A 465, 685). Parametrized by a set of Zernike polynomials, the OOF model correction was implemented into the active surface and has been applied during all high-frequency observations since Fall 2006, yielding a consistent gain curve that is flat with elevation. However, large-scale thermal deformation of the surface has remained a problem for daytime high-frequency observations. OOF holography maps taken throughout a clear winter day indicate that surface deformations become significant whenever the Sun is above 10 degrees elevation, but that they change slowly while tracking a single source. In this paper, we describe a further improvement to the GBT active surface that allows an observer to measure and compensate for the thermal surface deformation using the OOF technique. In order to support high-frequency observers, "AutoOOF" is a new GBT Astrid procedure that acquires a quick set of in-focus and out-of-focus on-the-fly continuum maps on a quasar using the currently active receiver. Upon completion of the maps, the data analysis software is launched automatically which produces and displays the surface map along with a set of Zernike coefficients. These coefficients are then sent to the active surface manager which combines them with the existing gravitational Zernike terms and FEM in order to compute the total active surface correction. The end-to-end functionality has been tested on the sky at Q-Band and Ka-band during

Removal of daytime thermal deformations in the GBT active surface via out-of-focus holography

NASA Astrophysics Data System (ADS)

Hunter, T. R.; Mello, M.; Nikolic, B.; Mason, B. S.; Schwab, F. R.; Ghigo, F. D.; Dicker, S. R.

2009-01-01

The 100-m diameter Green Bank Telescope (GBT) was built with an active surface of 2209 actuators in order to achieve and maintain an accurate paraboloidal shape. While much of the large-scale gravitational deformation of the surface can be described by a finite element model, a significant uncompensated gravitational deformation exists. In recent years, the elevation-dependence of this residual deformation has been successfully measured during benign nighttime conditions using the out-of-focus (OOF) holography technique (Nikolic et al, 2007, A&A 465, 685). Parametrized by a set of Zernike polynomials, the OOF model correction was implemented into the active surface and has been applied during all high frequency observations since Fall 2006, yielding a consistent gain curve that is constant with elevation. However, large-scale thermal deformation of the surface has remained a problem for daytime high-frequency observations. OOF holography maps taken throughout a clear winter day indicate that surface deformations become significant whenever the Sun is above 10 degrees elevation, but that they change slowly while tracking a single source. In this paper, we describe a further improvement to the GBT active surface that allows an observer to measure and compensate for the thermal surface deformation using the OOF technique. In order to support high-frequency observers, "AutoOOF" is a new GBT Astrid procedure that acquires a quick set of in-focus and out-of-focus on-the-fly continuum maps on a quasar using the currently active receiver. Upon completion of the maps, the data analysis software is launched automatically which produces and displays the surface map along with a set of Zernike coefficients. These coefficients are then sent to the active surface manager which combines them with the existing gravitational Zernike terms and FEM in order to compute the total active surface correction. The end-to-end functionality has been tested on the sky at Q-Band and Ka

Management of Congenital Chest Wall Deformities

PubMed Central

Blanco, Felix C.; Elliott, Steven T.; Sandler, Anthony D.

2011-01-01

Congenital chest wall deformities are considered to be anomalies in chest wall growth. These can be categorized as either rib cage overgrowth or deformities related to inadequate growth (aplasia or dysplasia). Rib cage overgrowth leads to depression of the sternum (pectus excavatum) or protuberance of the sternum (pectus carinatum) and accounts for greater than 90% of congenital chest wall deformities. The remaining deformities are a result of inadequate growth. Evolution in the management of congenital chest wall deformities has made significant progress over the past 25 years. This article will review chest wall deformities and the current management strategies of these interesting anomalies. PMID:22294949

Interfacial Bubble Deformations

NASA Astrophysics Data System (ADS)

Seymour, Brian; Shabane, Parvis; Cypull, Olivia; Cheng, Shengfeng; Feitosa, Klebert

Soap bubbles floating at an air-water experience deformations as a result of surface tension and hydrostatic forces. In this experiment, we investigate the nature of such deformations by taking cross-sectional images of bubbles of different volumes. The results show that as their volume increases, bubbles transition from spherical to hemispherical shape. The deformation of the interface also changes with bubble volume with the capillary rise converging to the capillary length as volume increases. The profile of the top and bottom of the bubble and the capillary rise are completely determined by the volume and pressure differences. James Madison University Department of Physics and Astronomy, 4VA Consortium, Research Corporation for Advancement of Science.

Deformation-induced crystallographic-preferred orientation of hcp-iron: An experimental study using a deformation-DIA apparatus

NASA Astrophysics Data System (ADS)

Nishihara, Yu; Ohuchi, Tomohiro; Kawazoe, Takaaki; Seto, Yusuke; Maruyama, Genta; Higo, Yuji; Funakoshi, Ken-ichi; Tange, Yoshinori; Irifune, Tetsuo

2018-05-01

Shear and uniaxial deformation experiments on hexagonal close-packed iron (hcp-Fe) was conducted using a deformation-DIA apparatus at a pressure of 13-17 GPa and a temperature of 723 K to determine its deformation-induced crystallographic-preferred orientation (CPO). Development of the CPO in the deforming sample is determined in-situ based on two-dimensional X-ray diffraction using monochromatic synchrotron X-rays. In the shear deformation geometry, the <0001> and < 11 2 bar 0 > axes gradually align to be sub-parallel to the shear plane normal and shear direction, respectively, from the initial random texture. In the uniaxial compression and tensile geometry, the <0001> and < 11 2 bar 0 > axes, respectively, gradually align along the direction of the uniaxial deformation axis. These results suggest that basal slip (0001) < 11 2 bar 0 > is the dominant slip system in hcp-Fe under the studied deformation conditions. The P-wave anisotropy for a shear deformed sample was calculated using elastic constants at the inner core condition by recent ab-initio calculations. Strength of the calculated anisotropy was comparable to or higher than axisymmetric anisotropy in Earth's inner core.

Late-Paleozoic-Mesozoic deformational and deformation related metamorphic structures of Kuznetsk-Altai region

NASA Astrophysics Data System (ADS)

Zinoviev, Sergei

2014-05-01

Kuznetsk-Altai region is a part of the Central Asian Orogenic Belt. The nature and formation mechanisms of the observed structure of Kuznetsk-Altai region are interpreted by the author as the consequence of convergence of Tuva-Mongolian and Junggar lithospheric block structures and energy of collision interaction between the blocks of crust in Late-Paleozoic-Mesozoic period. Tectonic zoning of Kuznetsk-Altai region is based on the principle of adequate description of geological medium (without methods of 'primary' state recovery). The initial indication of this convergence is the crust thickening in the zone of collision. On the surface the mechanisms of lateral compression form a regional elevation; with this elevation growth the 'mountain roots' start growing. With an approach of blocks an interblock elevation is divided into various fragments, and these fragments interact in the manner of collision. The physical expression of collision mechanisms are periodic pulses of seismic activity. The main tectonic consequence of the block convergence and collision of interblock units is formation of an ensemble of regional structures of the deformation type on the basis of previous 'pre-collision' geological substratum [Chikov et al., 2012]. This ensemble includes: 1) allochthonous and autochthonous blocks of weakly deformed substratum; 2) folded (folded-thrust) systems; 3) dynamic metamorphism zones of regional shears and main faults. Characteristic of the main structures includes: the position of sedimentary, magmatic and PT-metamorphic rocks, the degree of rock dynamometamorphism and variety rock body deformation, as well as the styles and concentrations of mechanic deformations. 1) block terranes have weakly elongated or isometric shape in plane, and they are the systems of block structures of pre-collision substratum separated by the younger zones of interblock deformations. They stand out among the main deformation systems, and the smallest are included into the

A GPU based high-resolution multilevel biomechanical head and neck model for validating deformable image registration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neylon, J., E-mail: jneylon@mednet.ucla.edu; Qi, X.; Sheng, K.

that may be caused by the biomechanical deformation process. Accuracy and stability of the model response were validated using ground-truth simulations representing soft tissue behavior under local and global deformations. Numerical accuracy of the HN deformations was analyzed by applying nonrigid skeletal transformations acquired from interfraction kVCT images to the model’s skeletal structures and comparing the subsequent soft tissue deformations of the model with the clinical anatomy. Results: The GPU based framework enabled the model deformation to be performed at 60 frames/s, facilitating simulations of posture changes and physiological regressions at interactive speeds. The soft tissue response was accurate with a R{sup 2} value of >0.98 when compared to ground-truth global and local force deformation analysis. The deformation of the HN anatomy by the model agreed with the clinically observed deformations with an average correlation coefficient of 0.956. For a clinically relevant range of posture and physiological changes, the model deformations stabilized with an uncertainty of less than 0.01 mm. Conclusions: Documenting dose delivery for HN radiotherapy is essential accounting for posture and physiological changes. The biomechanical model discussed in this paper was able to deform in real-time, allowing interactive simulations and visualization of such changes. The model would allow patient specific validations of the DIR method and has the potential to be a significant aid in adaptive radiotherapy techniques.« less

The Rubber Hand Illusion: Feeling of Ownership and Proprioceptive Drift Do Not Go Hand in Hand

PubMed Central

Rohde, Marieke; Di Luca, Massimiliano; Ernst, Marc O.

2011-01-01

In the Rubber Hand Illusion, the feeling of ownership of a rubber hand displaced from a participant's real occluded hand is evoked by synchronously stroking both hands with paintbrushes. A change of perceived finger location towards the rubber hand (proprioceptive drift) has been reported to correlate with this illusion. To measure the time course of proprioceptive drift during the Rubber Hand Illusion, we regularly interrupted stroking (performed by robot arms) to measure perceived finger location. Measurements were made by projecting a probe dot into the field of view (using a semi-transparent mirror) and asking participants if the dot is to the left or to the right of their invisible hand (Experiment 1) or to adjust the position of the dot to that of their invisible hand (Experiment 2). We varied both the measurement frequency (every 10 s, 40 s, 120 s) and the mode of stroking (synchronous, asynchronous, just vision). Surprisingly, with frequent measurements, proprioceptive drift occurs not only in the synchronous stroking condition but also in the two control conditions (asynchronous stroking, just vision). Proprioceptive drift in the synchronous stroking condition is never higher than in the just vision condition. Only continuous exposure to asynchronous stroking prevents proprioceptive drift and thus replicates the differences in drift reported in the literature. By contrast, complementary subjective ratings (questionnaire) show that the feeling of ownership requires synchronous stroking and is not present in the asynchronous stroking condition. Thus, subjective ratings and drift are dissociated. We conclude that different mechanisms of multisensory integration are responsible for proprioceptive drift and the feeling of ownership. Proprioceptive drift relies on visuoproprioceptive integration alone, a process that is inhibited by asynchronous stroking, the most common control condition in Rubber Hand Illusion experiments. This dissociation implies that

Hand washing promotion for preventing diarrhoea.

PubMed

Ejemot-Nwadiaro, Regina I; Ehiri, John E; Arikpo, Dachi; Meremikwu, Martin M; Critchley, Julia A

2015-09-03

Diarrhoea accounts for 1.8 million deaths in children in low- and middle-income countries (LMICs). One of the identified strategies to prevent diarrhoea is hand washing. To assess the effects of hand washing promotion interventions on diarrhoeal episodes in children and adults. We searched the Cochrane Infectious Diseases Group Specialized Register (27 May 2015); CENTRAL (published in the Cochrane Library 2015, Issue 5); MEDLINE (1966 to 27 May 2015); EMBASE (1974 to 27 May 2015); LILACS (1982 to 27 May 2015); PsycINFO (1967 to 27 May 2015); Science Citation Index and Social Science Citation Index (1981 to 27 May 2015); ERIC (1966 to 27 May 2015); SPECTR (2000 to 27 May 2015); Bibliomap (1990 to 27 May 2015); RoRe, The Grey Literature (2002 to 27 May 2015); World Health Organization (WHO) International Clinical Trial Registry Platform (ICTRP), metaRegister of Controlled Trials (mRCT), and reference lists of articles up to 27 May 2015. We also contacted researchers and organizations in the field. Individually randomized controlled trials (RCTs) and cluster-RCTs that compared the effects of hand washing interventions on diarrhoea episodes in children and adults with no intervention. Three review authors independently assessed trial eligibility, extracted data, and assessed risk of bias. We stratified the analyses for child day-care centres or schools, community, and hospital-based settings. Where appropriate, incidence rate ratios (IRR) were pooled using the generic inverse variance method and random-effects model with 95% confidence intervals (CIs). We used the GRADE approach to assess the quality of evidence. We included 22 RCTs: 12 trials from child day-care centres or schools in mainly high-income countries (54,006 participants), nine community-based trials in LMICs (15,303 participants), and one hospital-based trial among people with acquired immune deficiency syndrome (AIDS) (148 participants).Hand washing promotion (education activities, sometimes with

SU-F-BRF-10: Deformable MRI to CT Validation Employing Same Day Planning MRI for Surrogate Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Padgett, K; Stoyanova, R; Johnson, P

Purpose: To compare rigid and deformable registrations of the prostate in the multi-modality setting (diagnostic-MRI to planning-CT) by utilizing a planning-MRI as a surrogate. The surrogate allows for the direct quantitative analysis which can be difficult in the multi-modality domain where intensity mapping differs. Methods: For ten subjects, T2 fast-spin-echo images were acquired at two different time points, the first several weeks prior to planning (diagnostic-MRI) and the second on the same day in which the planning CT was collected (planning-MRI). Significant effort in patient positioning and bowel/bladder preparation was undertaken to minimize distortion of the prostate in all datasets.more » The diagnostic-MRI was deformed to the planning-CT utilizing a commercially available deformable registration algorithm synthesized from local registrations. The deformed MRI was then rigidly aligned to the planning MRI which was used as the surrogate for the planning-CT. Agreement between the two MRI datasets was scored using intensity based metrics including Pearson correlation and normalized mutual information, NMI. A local analysis was performed by looking only within the prostate, proximal seminal vesicles, penile bulb and combined areas. A similar method was used to assess a rigid registration between the diagnostic-MRI and planning-CT. Results: Utilizing the NMI, the deformable registrations were superior to the rigid registrations in 9 of 10 cases demonstrating a 15.94% improvement (p-value < 0.001) within the combined area. The Pearson correlation showed similar results with the deformable registration superior in the same number of cases and demonstrating a 6.97% improvement (p-value <0.011). Conclusion: Validating deformable multi-modality registrations using spatial intensity based metrics is difficult due to the inherent differences in intensity mapping. This population provides an ideal testing ground for MRI to CT deformable registrations by obviating

Fitting a hand-glove prosthesis to enhance the reconstructed mutilated hand.

PubMed

Leow, M E; Kour, A K; Pereira, B P; Pho, R W

1998-03-01

Microsurgical reconstruction of the severely mutilated hand aimed at improving prehensile functions often does not address the esthetic aspects of the hand. The poor appearance of the reconstructed hand affects its active display and use. A hand-glove prosthesis may be prescribed in this instance to enhance the overall form and function of the mutilated hand. We reviewed 16 cases of mutilating hand injuries in which surgical reconstructions were performed and the patients were subsequently fitted with a hand-glove prosthesis to augment the outcome. An improved appearance was achieved in all patients fitted with the prosthesis. The patients' sense of confidence was also enhanced, which in turn promoted the active and open use of the reconstructed hands. While prescribed primarily to improve the appearance of the reconstructed hands, these prostheses were documented to enhance the physical hand functions in 11 cases by increasing the span of the hand and providing an opposable post and a palmar base for holding and for anchorage. The prosthesis enhanced assistive functions of the reconstructed hands and freed the contralateral normal hand for use in bimanual activities, such as holding a wallet and taking out money, supporting a note pad for writing, and holding a plate at buffet receptions. At the 18-month follow-up visit, 13 (87%) of the patients continued to use their prosthesis. Wear and tear were problems associated with the frequent use of the prosthesis. The expected life span of the prosthesis with daily use ranged from 2 to 3 years. All the patients acknowledged that the prosthesis played a role in their rehabilitation and that it helped them to overcome the initial psychological trauma and to come to terms with their physical loss.

Possible Time Dependent Deformation over Socorro Magma Body from GPS and InSAR

NASA Astrophysics Data System (ADS)

Havazli, E.; Wdowinski, S.; Amelug, F.

2015-12-01

The Socorro Magma Body (SMB) is one of the largest, currently active magma intrusions in the Earth's continental crust. The area of Socorro is a segment of the Rio Grande Rift that display a broad seismic anomaly and ground deformation. The seismic reflector is imaged at 19 km depth coinciding with the occurrence of numerous small earthquake swarms. Broad crustal uplift was also observed above this reflector and led to the hypothesis of the presence of a large mid-crustal sill-like magma body. Previous geodetic studies over the area reveal ground deformation at the rate of 2-3 mm/yr from 1992 to 2006. The magma body was modeled as a penny-shaped crack of 21 km radius at 19 km depth based on InSAR results [Finnegan et. al., 2009]. In this study we expand the uplift measurement period over the SMB to two decades by using additional InSAR and GPS observations. We extended the InSAR observation record by analyzing 27 Envisat scenes acquired during the years 2006-2010. Continuous GPS observation acquired by the SC01 station since 2001 and three more recent Plate Boundary Observatory stations, which were installed between 2005 and 2011, provide high temporal record of uplift over the past decade and a half. We analyzed the InSAR data using ROI_PAC software package and calculated the temporal evolution of the vertical displacement using time series analysis. Preliminary results of 2006-2010 Envisat data show no significant deformation above the 1-2 mm noise level, which disagree with the previous ERS-1/2 results; 2-3 mm/yr during 1992-2006. This disagreement suggests a time dependent uplift of the SMB, which is also supported by GPS observations. The average uplift rate of the SC01 station is 0.9±0.02 mm/yr for 2001-2015 and 0.6±0.08 mm/yr for 2006-2010. Furthermore the SC01 time series exhibits episodic uplift events. The observed time dependent uplift suggests that magma supply in the middle crust may also occur episodically, as in shallow magmatic systems.

Homogeneous Yang-Baxter deformations as generalized diffeomorphisms

NASA Astrophysics Data System (ADS)

Sakamoto, Jun-ichi; Sakatani, Yuho; Yoshida, Kentaroh

2017-10-01

Yang-Baxter (YB) deformations of string sigma model provide deformed target spaces. We propose that homogeneous YB deformations always lead to a certain class of β-twisted backgrounds and represent the bosonic part of the supergravity fields in terms of the classical r-matrix associated with the YB deformation. We then show that various β-twisted backgrounds can be realized by considering generalized diffeomorphisms in the undeformed background. Our result extends the notable relation between the YB deformations and (non-commuting) TsT transformations. We also discuss more general deformations beyond the YB deformations.

Measurement of Seafloor Deformation in the Marine Sector of the Campi Flegrei Caldera (Italy)

NASA Astrophysics Data System (ADS)

Iannaccone, Giovanni; Guardato, Sergio; Donnarumma, Gian Paolo; De Martino, Prospero; Dolce, Mario; Macedonio, Giovanni; Chierici, Francesco; Beranzoli, Laura

2018-01-01

We present an assessment of vertical seafloor deformation in the shallow marine sector of the Campi Flegrei caldera (southern Italy) obtained from GPS and bottom pressure recorder (BPR) data, acquired over the period April 2016 to July 2017 in the Gulf of Pozzuoli by a new marine infrastructure, MEDUSA. This infrastructure consists of four fixed buoys with GPS receivers; each buoy is connected by cable to a seafloor multisensor module hosting a BPR. The measured maximum vertical uplift of the seafloor is about 4.2 ± 0.4 cm. The MEDUSA data were then compared to the expected vertical displacement in the marine sector according to a Mogi model point source computed using only GPS land measurements. The results show that a single point source model of deformation is able to explain both the GPS land and seafloor data. Moreover, we demonstrate that a network of permanent GPS buoys represents a powerful tool to measure the seafloor vertical deformation field in shallow water. The performance of this system is comparable to on-land high-precision GPS networks, marking a significant achievement and advance in seafloor geodesy and extending volcano monitoring capabilities to shallow offshore areas (up to 100 m depth). The GPS measurements of MEDUSA have also been used to confirm that the BPR data provide an independent measure of the seafloor vertical uplift in shallow water.

Linear and nonlinear subspace analysis of hand movements during grasping.

PubMed

Cui, Phil Hengjun; Visell, Yon

2014-01-01

This study investigated nonlinear patterns of coordination, or synergies, underlying whole-hand grasping kinematics. Prior research has shed considerable light on roles played by such coordinated degrees-of-freedom (DOF), illuminating how motor control is facilitated by structural and functional specializations in the brain, peripheral nervous system, and musculoskeletal system. However, existing analyses suppose that the patterns of coordination can be captured by means of linear analyses, as linear combinations of nominally independent DOF. In contrast, hand kinematics is itself highly nonlinear in nature. To address this discrepancy, we sought to to determine whether nonlinear synergies might serve to more accurately and efficiently explain human grasping kinematics than is possible with linear analyses. We analyzed motion capture data acquired from the hands of individuals as they grasped an array of common objects, using four of the most widely used linear and nonlinear dimensionality reduction algorithms. We compared the results using a recently developed algorithm-agnostic quality measure, which enabled us to assess the quality of the dimensional reductions that resulted by assessing the extent to which local neighborhood information in the data was preserved. Although qualitative inspection of this data suggested that nonlinear correlations between kinematic variables were present, we found that linear modeling, in the form of Principle Components Analysis, could perform better than any of the nonlinear techniques we applied.

A method to estimate the effect of deformable image registration uncertainties on daily dose mapping

PubMed Central

Murphy, Martin J.; Salguero, Francisco J.; Siebers, Jeffrey V.; Staub, David; Vaman, Constantin

2012-01-01

Purpose: To develop a statistical sampling procedure for spatially-correlated uncertainties in deformable image registration and then use it to demonstrate their effect on daily dose mapping. Methods: Sequential daily CT studies are acquired to map anatomical variations prior to fractionated external beam radiotherapy. The CTs are deformably registered to the planning CT to obtain displacement vector fields (DVFs). The DVFs are used to accumulate the dose delivered each day onto the planning CT. Each DVF has spatially-correlated uncertainties associated with it. Principal components analysis (PCA) is applied to measured DVF error maps to produce decorrelated principal component modes of the errors. The modes are sampled independently and reconstructed to produce synthetic registration error maps. The synthetic error maps are convolved with dose mapped via deformable registration to model the resulting uncertainty in the dose mapping. The results are compared to the dose mapping uncertainty that would result from uncorrelated DVF errors that vary randomly from voxel to voxel. Results: The error sampling method is shown to produce synthetic DVF error maps that are statistically indistinguishable from the observed error maps. Spatially-correlated DVF uncertainties modeled by our procedure produce patterns of dose mapping error that are different from that due to randomly distributed uncertainties. Conclusions: Deformable image registration uncertainties have complex spatial distributions. The authors have developed and tested a method to decorrelate the spatial uncertainties and make statistical samples of highly correlated error maps. The sample error maps can be used to investigate the effect of DVF uncertainties on daily dose mapping via deformable image registration. An initial demonstration of this methodology shows that dose mapping uncertainties can be sensitive to spatial patterns in the DVF uncertainties. PMID:22320766

Hand washing promotion for preventing diarrhoea

PubMed Central

Ejemot-Nwadiaro, Regina I; Ehiri, John E; Arikpo, Dachi; Meremikwu, Martin M; Critchley, Julia A

2015-01-01

Background Diarrhoea accounts for 1.8 million deaths in children in low- and middle-income countries (LMICs). One of the identified strategies to prevent diarrhoea is hand washing. Objectives To assess the effects of hand washing promotion interventions on diarrhoeal episodes in children and adults. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register (27 May 2015); CENTRAL (published in the Cochrane Library 2015, Issue 5); MEDLINE (1966 to 27 May 2015); EMBASE (1974 to 27 May 2015); LILACS (1982 to 27 May 2015); PsycINFO (1967 to 27 May 2015); Science Citation Index and Social Science Citation Index (1981 to 27 May 2015); ERIC (1966 to 27 May 2015); SPECTR (2000 to 27 May 2015); Bibliomap (1990 to 27 May 2015); RoRe, The Grey Literature (2002 to 27 May 2015); World Health Organization (WHO) International Clinical Trial Registry Platform (ICTRP), metaRegister of Controlled Trials (mRCT), and reference lists of articles up to 27 May 2015. We also contacted researchers and organizations in the field. Selection criteria Individually randomized controlled trials (RCTs) and cluster-RCTs that compared the effects of hand washing interventions on diarrhoea episodes in children and adults with no intervention. Data collection and analysis Three review authors independently assessed trial eligibility, extracted data, and assessed risk of bias. We stratified the analyses for child day-care centres or schools, community, and hospital-based settings. Where appropriate, incidence rate ratios (IRR) were pooled using the generic inverse variance method and random-effects model with 95% confidence intervals (CIs). We used the GRADE approach to assess the quality of evidence. Main results We included 22 RCTs: 12 trials from child day-care centres or schools in mainly high-income countries (54,006 participants), nine community-based trials in LMICs (15,303 participants), and one hospital-based trial among people with acquired immune deficiency

Deformation twinning: Influence of strain rate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gray, G.T. III

Twins in most crystal structures, including advanced materials such as intermetallics, form more readily as the temperature of deformation is decreased or the rate of deformation is increased. Both parameters lead to the suppression of thermally-activated dislocation processes which can result in stresses high enough to nucleate and grow deformation twins. Under high-strain rate or shock-loading/impact conditions deformation twinning is observed to be promoted even in high stacking fault energy FCC metals and alloys, composites, and ordered intermetallics which normally do not readily deform via twinning. Under such conditions and in particular under the extreme loading rates typical of shockmore » wave deformation the competition between slip and deformation twinning can be examined in detail. In this paper, examples of deformation twinning in the intermetallics TiAl, Ti-48Al-lV and Ni{sub 3}A as well in the cermet Al-B{sub 4}C as a function of strain rate will be presented. Discussion includes: (1) the microstructural and experimental variables influencing twin formation in these systems and twinning topics related to high-strain-rate loading, (2) the high velocity of twin formation, and (3) the influence of deformation twinning on the constitutive response of advanced materials.« less

SU-E-J-109: Accurate Contour Transfer Between Different Image Modalities Using a Hybrid Deformable Image Registration and Fuzzy Connected Image Segmentation Method.

PubMed

Yang, C; Paulson, E; Li, X

2012-06-01

To develop and evaluate a tool that can improve the accuracy of contour transfer between different image modalities under challenging conditions of low image contrast and large image deformation, comparing to a few commonly used methods, for radiation treatment planning. The software tool includes the following steps and functionalities: (1) accepting input of images of different modalities, (2) converting existing contours on reference images (e.g., MRI) into delineated volumes and adjusting the intensity within the volumes to match target images (e.g., CT) intensity distribution for enhanced similarity metric, (3) registering reference and target images using appropriate deformable registration algorithms (e.g., B-spline, demons) and generate deformed contours, (4) mapping the deformed volumes on target images, calculating mean, variance, and center of mass as the initialization parameters for consecutive fuzzy connectedness (FC) image segmentation on target images, (5) generate affinity map from FC segmentation, (6) achieving final contours by modifying the deformed contours using the affinity map with a gradient distance weighting algorithm. The tool was tested with the CT and MR images of four pancreatic cancer patients acquired at the same respiration phase to minimize motion distortion. Dice's Coefficient was calculated against direct delineation on target image. Contours generated by various methods, including rigid transfer, auto-segmentation, deformable only transfer and proposed method, were compared. Fuzzy connected image segmentation needs careful parameter initialization and user involvement. Automatic contour transfer by multi-modality deformable registration leads up to 10% of accuracy improvement over the rigid transfer. Two extra proposed steps of adjusting intensity distribution and modifying the deformed contour with affinity map improve the transfer accuracy further to 14% averagely. Deformable image registration aided by contrast adjustment

Guideline Implementation: Hand Hygiene.

PubMed

Goldberg, Judith L

2017-02-01

Performing proper hand hygiene and surgical hand antisepsis is essential to reducing the rates of health care-associated infections, including surgical site infections. The updated AORN "Guideline for hand hygiene" provides guidance on hand hygiene and surgical hand antisepsis, the wearing of fingernail polish and artificial nails, proper skin care to prevent dermatitis, the wearing of jewelry, hand hygiene product selection, and quality assurance and performance improvement considerations. This article focuses on key points of the guideline to help perioperative personnel make informed decisions about hand hygiene and surgical hand antisepsis. The key points address the necessity of keeping fingernails and skin healthy, not wearing jewelry on the hands or wrists in the perioperative area, properly performing hand hygiene and surgical hand antisepsis, and involving patients and visitors in hand hygiene initiatives. Perioperative RNs should review the complete guideline for additional information and for guidance when writing and updating policies and procedures. Copyright © 2017 AORN, Inc. Published by Elsevier Inc. All rights reserved.

Polygonal deformation bands in sandstone

NASA Astrophysics Data System (ADS)

Antonellini, Marco; Nella Mollema, Pauline

2017-04-01

We report for the first time the occurrence of polygonal faults in sandstone, which is compelling given that layer-bound polygonal fault systems have been observed so far only in fine-grained sediments such as clay and chalk. The polygonal faults are dm-wide zones of shear deformation bands that developed under shallow burial conditions in the lower portion of the Jurassic Entrada Fm (Utah, USA). The edges of the polygons are 1 to 5 meters long. The shear deformation bands are organized as conjugate faults along each edge of the polygon and form characteristic horst-like structures. The individual deformation bands have slip magnitudes ranging from a few mm to 1.5 cm; the cumulative average slip magnitude in a zone is up to 10 cm. The deformation bands heaves, in aggregate form, accommodate a small isotropic horizontal extension (strain < 0.005). The individual shear deformation bands show abutting T-junctions, veering, curving, and merging where they mechanically interact. Crosscutting relationships are rare. The interactions of the deformation bands are similar to those of mode I opening fractures. Density inversion, that takes place where under-compacted and over-pressurized layers (Carmel Fm) lay below normally compacted sediments (Entrada Sandstone), may be an important process for polygonal deformation bands formation. The gravitational sliding and soft sediment structures typically observed within the Carmel Fm support this hypothesis. Soft sediment deformation may induce polygonal faulting in the section of the Entrada Sandstone just above the Carmel Fm. The permeability of the polygonal deformation bands is approximately 10-14 to 10-13 m2, which is less than the permeability of the host, Entrada Sandstone (range 10-12 to 10-11 m2). The documented fault networks have important implications for evaluating the geometry of km-scale polygonal fault systems in the subsurface, top seal integrity, as well as constraining paleo-tectonic stress regimes.

Occurrence of oral deformities in larval anurans

USGS Publications Warehouse

Drake, D.L.; Altig, R.; Grace, J.B.; Walls, S.C.

2007-01-01

We quantified deformities in the marginal papillae, tooth rows, and jaw sheaths of tadpoles from 13 population samples representing three families and 11 sites in the southeastern United States. Oral deformities were observed in all samples and in 13.5-98% of the specimens per sample. Batrachochytrium dendrobatidis (chytrid) infections were detected in three samples. There was high variability among samples in the pattern and number of discovered deformities. Pairwise associations between oral structures containing deformities were nonrandom for several populations, especially those with B. dendrobatidis infections or high total numbers of deformities. Comparisons of deformities among samples using multivariate analyses revealed that tadpole samples grouped together by family. Analyses of ordination indicated that three variables, the number of deformities, the number of significant associations among deformity types within populations, and whether populations were infected with B. dendrobatidis, were significantly correlated with the pattern of deformities. Our data indicate that the incidence of oral deformities can be high in natural populations and that phylogeny and B. dendrobatidis infection exert a strong influence on the occurrence and type of oral deformities in tadpoles. ?? by the American Society of Ichthyologists and Herperologists.

Deformable 3D-2D registration for guiding K-wire placement in pelvic trauma surgery

NASA Astrophysics Data System (ADS)

Goerres, J.; Jacobson, M.; Uneri, A.; de Silva, T.; Ketcha, M.; Reaungamornrat, S.; Vogt, S.; Kleinszig, G.; Wolinsky, J.-P.; Osgood, G.; Siewerdsen, J. H.

2017-03-01

Pelvic Kirschner wire (K-wire) insertion is a challenging surgical task requiring interpretation of complex 3D anatomical shape from 2D projections (fluoroscopy) and delivery of device trajectories within fairly narrow bone corridors in proximity to adjacent nerves and vessels. Over long trajectories ( 10-25 cm), K-wires tend to curve (deform), making conventional rigid navigation inaccurate at the tip location. A system is presented that provides accurate 3D localization and guidance of rigid or deformable surgical devices ("components" - e.g., K-wires) based on 3D-2D registration. The patient is registered to a preoperative CT image by virtually projecting digitally reconstructed radiographs (DRRs) and matching to two or more intraoperative x-ray projections. The K-wire is localized using an analogous procedure matching DRRs of a deformably parametrized model for the device component (deformable known-component registration, or dKC-Reg). A cadaver study was performed in which a K-wire trajectory was delivered in the pelvis. The system demonstrated target registration error (TRE) of 2.1 ± 0.3 mm in location of the K-wire tip (median ± interquartile range, IQR) and 0.8 ± 1.4º in orientation at the tip (median ± IQR), providing functionality analogous to surgical tracking / navigation using imaging systems already in the surgical arsenal without reliance on a surgical tracker. The method offers quantitative 3D guidance using images (e.g., inlet / outlet views) already acquired in the standard of care, potentially extending the advantages of navigation to broader utilization in trauma surgery to improve surgical precision and safety.

Inspections of Hand Washing Supplies and Hand Sanitizer in Public Schools

ERIC Educational Resources Information Center

Ramos, Mary M.; Blea, Mary; Trujillo, Rebecca; Greenberg, Cynthia

2010-01-01

Hand washing and hand antisepsis are proven infection control measures in the school setting, yet barriers such as lack of soap, paper towels, and hand sanitizer can hinder compliance. This pilot study measured the prevalence of hand cleaning supplies in public schools. Ten school districts (93 schools) participated in school nurse inspections. In…

A virtual phantom library for the quantification of deformable image registration uncertainties in patients with cancers of the head and neck.

PubMed

Pukala, Jason; Meeks, Sanford L; Staton, Robert J; Bova, Frank J; Mañon, Rafael R; Langen, Katja M

2013-11-01

Deformable image registration (DIR) is being used increasingly in various clinical applications. However, the underlying uncertainties of DIR are not well-understood and a comprehensive methodology has not been developed for assessing a range of interfraction anatomic changes during head and neck cancer radiotherapy. This study describes the development of a library of clinically relevant virtual phantoms for the purpose of aiding clinicians in the QA of DIR software. These phantoms will also be available to the community for the independent study and comparison of other DIR algorithms and processes. Each phantom was derived from a pair of kVCT volumetric image sets. The first images were acquired of head and neck cancer patients prior to the start-of-treatment and the second were acquired near the end-of-treatment. A research algorithm was used to autosegment and deform the start-of-treatment (SOT) images according to a biomechanical model. This algorithm allowed the user to adjust the head position, mandible position, and weight loss in the neck region of the SOT images to resemble the end-of-treatment (EOT) images. A human-guided thin-plate splines algorithm was then used to iteratively apply further deformations to the images with the objective of matching the EOT anatomy as closely as possible. The deformations from each algorithm were combined into a single deformation vector field (DVF) and a simulated end-of-treatment (SEOT) image dataset was generated from that DVF. Artificial noise was added to the SEOT images and these images, along with the original SOT images, created a virtual phantom where the underlying "ground-truth" DVF is known. Images from ten patients were deformed in this fashion to create ten clinically relevant virtual phantoms. The virtual phantoms were evaluated to identify unrealistic DVFs using the normalized cross correlation (NCC) and the determinant of the Jacobian matrix. A commercial deformation algorithm was applied to the virtual

A novel design of membrane mirror with small deformation and imaging performance analysis in infrared system

NASA Astrophysics Data System (ADS)

Zhang, Shuqing; Wang, Yongquan; Zhi, Xiyang

2017-05-01

A method of diminishing the shape error of membrane mirror is proposed in this paper. The inner inflating pressure is considerably decreased by adopting the pre-shaped membrane. Small deformation of the membrane mirror with greatly reduced shape error is sequentially achieved. Primarily a finite element model of the above pre-shaped membrane is built on the basis of its mechanical properties. Then accurate shape data under different pressures can be acquired by iteratively calculating the node displacements of the model. Shape data are applicable to build up deformed reflecting surfaces for the simulative analysis in ZEMAX. Finally, ground-based imaging experiments of 4-bar targets and nature scene are conducted. Experiment results indicate that the MTF of the infrared system can reach to 0.3 at a high spatial resolution of 10l p/mm, and texture details of the nature scene are well-presented. The method can provide theoretical basis and technical support for the applications in lightweight optical components with ultra-large apertures.

Effect of hand sanitizer location on hand hygiene compliance.

PubMed

Cure, Laila; Van Enk, Richard

2015-09-01

Hand hygiene is the most important intervention to prevent infection in hospitals. Health care workers should clean their hands at least before and after contact with patients. Hand sanitizer dispensers are important to support hand hygiene because they can be made available throughout hospital units. The aim of this study was to determine whether the usability of sanitizer dispensers correlates with compliance of staff in using the sanitizer in a hospital. This study took place in a Midwest, 404-bed, private, nonprofit community hospital with 15 inpatient care units in addition to several ambulatory units. The usability and standardization of sanitizers in 12 participating inpatient units were evaluated. The hospital measured compliance of staff with hand hygiene as part of their quality improvement program. Data from 2010-2012 were analyzed to measure the relationship between compliance and usability using mixed-effects logistic regression models. The total usability score (P = .0046), visibility (P = .003), and accessibility of the sanitizer on entrance to the patient room (P = .00055) were statistically associated with higher observed compliance rates. Standardization alone showed no significant impact on observed compliance (P = .37). Hand hygiene compliance can be influenced by visibility and accessibility of dispensers. The sanitizer location should be part of multifaceted interventions to improve hand hygiene. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Acquired hyperpigmentations*

PubMed Central

Cestari, Tania Ferreira; Dantas, Lia Pinheiro; Boza, Juliana Catucci

2014-01-01

Cutaneous hyperpigmentations are frequent complaints, motivating around 8.5% of all dermatological consultations in our country. They can be congenital, with different patterns of inheritance, or acquired in consequence of skin problems, systemic diseases or secondary to environmental factors. The vast majority of them are linked to alterations on the pigment melanin, induced by different mechanisms. This review will focus on the major acquired hyperpigmentations associated with increased melanin, reviewing their mechanisms of action and possible preventive measures. Particularly prominent aspects of diagnosis and therapy will be emphasized, with focus on melasma, post-inflammatory hyperpigmentation, periorbital pigmentation, dermatosis papulosa nigra, phytophotodermatoses, flagellate dermatosis, erythema dyschromicum perstans, cervical poikiloderma (Poikiloderma of Civatte), acanthosis nigricans, cutaneous amyloidosis and reticulated confluent dermatitis PMID:24626644

InSAR Deformation Time Series Processed On-Demand in the Cloud

NASA Astrophysics Data System (ADS)

Horn, W. B.; Weeden, R.; Dimarchi, H.; Arko, S. A.; Hogenson, K.

2017-12-01

During this past year, ASF has developed a cloud-based on-demand processing system known as HyP3 (http://hyp3.asf.alaska.edu/), the Hybrid Pluggable Processing Pipeline, for Synthetic Aperture Radar (SAR) data. The system makes it easy for a user who doesn't have the time or inclination to install and use complex SAR processing software to leverage SAR data in their research or operations. One such processing algorithm is generation of a deformation time series product, which is a series of images representing ground displacements over time, which can be computed using a time series of interferometric SAR (InSAR) products. The set of software tools necessary to generate this useful product are difficult to install, configure, and use. Moreover, for a long time series with many images, the processing of just the interferograms can take days. Principally built by three undergraduate students at the ASF DAAC, the deformation time series processing relies the new Amazon Batch service, which enables processing of jobs with complex interconnected dependencies in a straightforward and efficient manner. In the case of generating a deformation time series product from a stack of single-look complex SAR images, the system uses Batch to serialize the up-front processing, interferogram generation, optional tropospheric correction, and deformation time series generation. The most time consuming portion is the interferogram generation, because even for a fairly small stack of images many interferograms need to be processed. By using AWS Batch, the interferograms are all generated in parallel; the entire process completes in hours rather than days. Additionally, the individual interferograms are saved in Amazon's cloud storage, so that when new data is acquired in the stack, an updated time series product can be generated with minimal addiitonal processing. This presentation will focus on the development techniques and enabling technologies that were used in developing the time

Long-term deformation in the Mississippi Embayment (Central USA) imaged by high-resolution seismic reflection data

NASA Astrophysics Data System (ADS)

Hao, Yanjun

Large magnitude intraplate earthquakes are a puzzling exception to plate tectonic theory. Unlike earthquakes occurring along plate boundaries, large continental intraplate earthquakes are a rare occurrence and are often distributed over broad regions. Albeit rare, their occurrence can cause widespread damage because of the low attenuation of seismic energy typical of plate interiors [Hanks and Johnston, 1992]. In the Central USA, most of the recent tectonic intraplate seismicity concentrates along the New Madrid seismic zone (NMSZ), where three large (M>7) earthquakes occurred between 1811--1812 [Johnston and Schweig, 1996]. Here the low surface deformation rates [Calais and Stein, 2009] conflict with the elevated instrument-recorded seismicity and the occurrence of historical and prehistorical large magnitude events [Tuttle et al., 2002]. One of the promising hypotheses proposed to reconcile this apparent contradiction is that intraplate earthquakes may be temporally clustered, episodic or cyclic, and may migrate spatially at the regional or continental scale across multiple faults or fault systems. In order to test this hypothesis and to understand how and where the long-term deformation is accommodated in the Mississippi Embayment, Central USA, I utilize high-resolution seismic reflection data acquired by the Mississippi River Project [Magnani and McIntosh, 2009] and by a 2010 survey across the Meeman-Shelby fault [Magnani, 2011; Hao et al., 2013]. To identify the location of Quaternary deformation and characterize deformation history, I acquired, processed, and interpreted the seismic reflection data and integrated them with other available geophysical (e.g. seismicity, crustal and lithospheric models) and geological (e.g. magmatism and borehole) data. For my research, I focus on three regions in the Mississippi Embayment: 1) the Meeman-Shelby fault west of Memphis, Tennessee, 2) the eastern Reelfoot rift margin north of Memphis, Tennessee, and 3) the area in

Multi-stage 3D-2D registration for correction of anatomical deformation in image-guided spine surgery

NASA Astrophysics Data System (ADS)

Ketcha, M. D.; De Silva, T.; Uneri, A.; Jacobson, M. W.; Goerres, J.; Kleinszig, G.; Vogt, S.; Wolinsky, J.-P.; Siewerdsen, J. H.

2017-06-01

A multi-stage image-based 3D-2D registration method is presented that maps annotations in a 3D image (e.g. point labels annotating individual vertebrae in preoperative CT) to an intraoperative radiograph in which the patient has undergone non-rigid anatomical deformation due to changes in patient positioning or due to the intervention itself. The proposed method (termed msLevelCheck) extends a previous rigid registration solution (LevelCheck) to provide an accurate mapping of vertebral labels in the presence of spinal deformation. The method employs a multi-stage series of rigid 3D-2D registrations performed on sets of automatically determined and increasingly localized sub-images, with the final stage achieving a rigid mapping for each label to yield a locally rigid yet globally deformable solution. The method was evaluated first in a phantom study in which a CT image of the spine was acquired followed by a series of 7 mobile radiographs with increasing degree of deformation applied. Second, the method was validated using a clinical data set of patients exhibiting strong spinal deformation during thoracolumbar spine surgery. Registration accuracy was assessed using projection distance error (PDE) and failure rate (PDE  >  20 mm—i.e. label registered outside vertebra). The msLevelCheck method was able to register all vertebrae accurately for all cases of deformation in the phantom study, improving the maximum PDE of the rigid method from 22.4 mm to 3.9 mm. The clinical study demonstrated the feasibility of the approach in real patient data by accurately registering all vertebral labels in each case, eliminating all instances of failure encountered in the conventional rigid method. The multi-stage approach demonstrated accurate mapping of vertebral labels in the presence of strong spinal deformation. The msLevelCheck method maintains other advantageous aspects of the original LevelCheck method (e.g. compatibility with standard clinical workflow, large

The use of the analytic hierarchy process to aid decision making in acquired equinovarus deformity.

PubMed

van Til, Janine A; Renzenbrink, Gerbert J; Dolan, James G; Ijzerman, Maarten J

2008-03-01

To increase the transparency of decision making about treatment in patients with equinovarus deformity poststroke. The analytic hierarchy process (AHP) was used as a structured methodology to study the subjective rationale behind choice of treatment. An 8-hour meeting at a centrally located rehabilitation center in The Netherlands, during which a patient video was shown to all participants (using a personal computer and a large screen) and the patient details were provided on paper. A panel of 10 health professionals from different backgrounds. Not applicable. The performance of the applicable treatments on outcome, impact, comfort, cosmetics, daily effort, and risks and side effects of treatment, as well as the relative importance of criteria in the choice of treatment. According to the model, soft-tissue surgery (.413) ranked first as the preferred treatment, followed by orthopedic footwear (.181), ankle-foot orthosis (.147), surface electrostimulation (.137), and finally implanted electrostimulation (.123). Outcome was the most influential consideration affecting treatment choice (.509), followed by risk and side effects (.194), comfort (.104), daily effort (.098), cosmetics (.065), and impact of treatment (.030). Soft-tissue surgery was judged best on outcome, daily effort, comfortable shoe wear, and cosmetically acceptable result and was thereby preferred as a treatment alternative by the panel in this study. In contrast, orthosis and orthopedic footwear are usually preferred in daily practice. The AHP method was found to be suitable methodology for eliciting subjective opinions and quantitatively comparing treatments in the absence of scientific evidence.

17 CFR 210.8-06 - Real estate operations acquired or to be acquired.

Code of Federal Regulations, 2010 CFR

2010-04-01

... EXCHANGE COMMISSION FORM AND CONTENT OF AND REQUIREMENTS FOR FINANCIAL STATEMENTS, SECURITIES ACT OF 1933..., INVESTMENT ADVISERS ACT OF 1940, AND ENERGY POLICY AND CONSERVATION ACT OF 1975 Article 8 Financial Statements of Smaller Reporting Companies § 210.8-06 Real estate operations acquired or to be acquired. If...

Inventory of anthropogenic surface deformation measured by InSAR in the western U.S./Mexico and possible impacts on GPS measurements

NASA Astrophysics Data System (ADS)

Semple, A.; Pritchard, M. E.; Taylor, H.

2014-12-01

The western US and Mexico are deforming at several spatial scales that can be measured by ground and satellite observations like GPS and Interferometric Synthetic Aperture Radar (InSAR). Many GPS stations have been installed throughout this area to monitor ground deformation caused by large scale tectonic processes; however, several studies have noted that the data recorded at a GPS station can be contaminated by local, non-tectonic ground deformation. In this study, we use InSAR to examine deformation from various sources in the western US and Mexico. We chose this method due to the spatially large study area and the availability and temporal coverage of SAR imagery. We use SAR images acquired by the satellites Envisat, ERS-1 and ERS-2 over a time period from 1992-2010 to create several time series. Data from the ALOS satellite between 2006-2011 are also used in some areas. We use these time series analysis along with previously published results to observe and catalogue various sources of surface deformation in the western US and Mexico - from groundwater pumping, geothermal activity, mining, hydrocarbon production, and other sources. We then use these results to identify GPS stations that have potentially been contaminated by non-tectonic deformation signals. We document more than 150 distinct regions of non-tectonic and likely anthropogenic deformation. We have located 82 GPS stations within 20km of the center of at least one of the non-tectonic deformation signals we have identified. It is likely that the data from these 82 GPS stations have been contaminated by local anthropogenic deformation. Some examples of previously unpublished non-tectonic deformation we have seen in this study include but are not limited to, subsidence due to groundwater extraction in Jesus Garcia, Mexico, both uplift and subsidence due to natural gas extraction at Jonah Field in Sublette County, WY, and uplift due to a water recharge project in Tonopah, AZ.

Monitoring deformation at the Geysers Geothermal Field, California using C-band and X-band interferometric synthetic aperture radar

DOE PAGES

Vasco, D. W.; Rutqvist, Jonny; Ferretti, Alessandro; ...

2013-06-07

In this study, we resolve deformation at The Geysers Geothermal Field using two distinct sets of interferometric synthetic aperture radar (InSAR) data. The first set of observations utilize archived European Space Agency C-band synthetic aperture radar data from 1992 through 1999 to image the long-term and large-scale subsidence at The Geysers. The peak range velocity of approximately 50 mm/year agrees with previous estimates from leveling and global positioning system observations. Data from a second set of measurements, acquired by TerraSAR-X satellites, extend from May 2011 until April 2012 and overlap the C-band data spatially but not temporally. These X-band data,more » analyzed using a combined permanent and distributed scatterer algorithm, provide a higher density of scatterers (1122 per square kilometer) than do the C-band data (12 per square kilometer). The TerraSAR-X observations resolve 1 to 2 cm of deformation due to water injection into a Northwest Geysers enhanced geothermal system well, initiated on October 2011. Lastly, the temporal variation of the deformation is compatible with estimates from coupled numerical modeling.« less

Lateral column lengthening for acquired adult flatfoot deformity caused by posterior tibial tendon dysfunction stage II: a retrospective comparison of calcaneus osteotomy with calcaneocuboid distraction arthrodesis.

PubMed

Haeseker, Guus A; Mureau, Marc A; Faber, Frank W M

2010-01-01

In this study, clinical and radiological results after lateral column lengthening by calcaneocuboid distraction arthrodesis and calcaneus osteotomy were compared. Thirty-three patients (35 feet) treated with lateral column lengthening by distraction arthrodesis (14 patients, 16 feet; group I) or by calcaneus osteotomy (19 patients, 19 feet; group II) for adult-acquired flatfoot deformity caused by stage II posterior tibial tendon dysfunction were compared retrospectively. Mean follow-up was 42.4 months (range, 6-78 months) for group I and 15.8 months (range, 6-32 months) for group II (P < .001). The American Orthopaedic Foot & Ankle Society ankle-hindfoot score was determined, 4 variables were measured on preoperative and postoperative weight-bearing radiographs, and a number of independent and outcome variables, including patient satisfaction, were recorded. Group 2 had a significantly higher American Orthopaedic Foot & Ankle Society score compared with group I (mean, 85 vs. 72, respectively; P < .02) at time of last follow-up, and there were no dissatisfied patients in group I, whereas 2 patients in group II were dissatisfied with the result of the operation. All radiological results were significantly better at time of follow-up in both groups (except for talocalcaneal angle in group I), although no significant differences were noted in the amount of change in radiographic measurements between the groups. No significant correlation was found between follow-up time and radiographic improvement, indicating stable radiographic measurements over time. In group II, 13 mild calcaneocuboid subluxations were observed. In both groups, 1 nonunion and 1 wound complication occurred. Based on our experience with the patients described in this report, we recommend lateral column lengthening by means of calcaneus osteotomy rather than distraction arthrodesis of the calcaneocuboid joint, for correction of stage II posterior tibial tendon dysfunction. Copyright 2010 American

HandTutor™ enhanced hand rehabilitation after stroke--a pilot study.

PubMed

Carmeli, Eli; Peleg, Sara; Bartur, Gadi; Elbo, Enbal; Vatine, Jean-Jacques

2011-12-01

This study assessed the potential therapeutic benefi t of using HandTutor™ in combination with traditional rehabilitation in a post-stroke sub-acute population. The study compares an experimental group receiving traditional therapy combined with HandTutorTM treatment, against a control group receiving only traditional therapy. An assessor-blinded, randomized controlled pilot trial, was conducted in the Reuth rehabilitation unit in Israel. Thirty-one stroke patients in the sub-acute phase, were randomly assigned to one of the two groups (experimental or control) in sets of three. The experimental group (n = 16) underwent a hand rehabilitation programme using the HandTutorTM combined with traditional therapy. The control group (n = 15) received only traditional therapy. The treatment schedules for both groups were of similar duration and frequency. Improvements were evaluated using three indicators: 1) The Brunnström-Fugl-Meyer (FM) test, 2) the Box and Blocks (B&B) test and 3) improvement parameters as determined by the HandTutorTM software. Following 15 consecutive treatment sessions, a signifi cant improvement was observed within the experimental group (95% confi dence intervals) compared with the control group: B&B p = 0.015; FM p = 0.041, HandTutor™ performance accuracy on x axis and performance accuracy on y axis p < 0.0003. The results from this pilot study support further investigation of the use of the HandTutorTM in combination with traditional occupational therapy and physiotherapy during post stroke hand function rehabilitation.

Behavior of lateral-deformation coefficients during elastoplastic deformation of metals

NASA Astrophysics Data System (ADS)

Zimin, B. A.; Smirnov, I. V.; Sudenkov, Yu. V.

2017-06-01

The results of investigations into variation of the coefficients of lateral deformation (the Poisson ratio) during single-axis tension of samples of steel 12Kh18N10T and St3, titanium VT1, the aluminum alloy D16AM, copper M1, and a magnesium alloy are considered. The technique developed on the basis of the optoacoustic effect and simultaneous measurements of the longitudinal and surface speeds of sound in metallic samples during the tension makes it possible to measure the rates at various stages of the deformation process. The data obtained make it possible to construct the dependences of variation of the lateral-deformation coefficients at all stages of the plastic flow. The correlation of these variations both with known processes of structural reconstructions at various stages of plastic flow and with the process of localization of plastic-shear bands in the aluminum alloy is noted.

Hand Washing Induces a Clean Slate Effect in Moral Judgments: A Pupillometry and Eye-Tracking Study

PubMed Central

Kaspar, Kai; Krapp, Vanessa; König, Peter

2015-01-01

Physical cleansing is commonly understood to protect us against physical contamination. However, recent studies showed additional effects on moral judgments. Under the heading of the “Macbeth effect” direct links between bodily cleansing and one’s own moral purity have been demonstrated. Here we investigate (1) how moral judgments develop over time and how they are altered by hand washing, (2) whether changes in moral judgments can be explained by altered information sampling from the environment, and (3) whether hand washing affects emotional arousal. Using a pre-post control group design, we found that morality ratings of morally good and bad scenes acquired more extreme values in the control group over time, an effect that was fully counteracted by intermediate hand washing. This result supports the notion of a clean slate effect by hand washing. Thereby, eye-tracking data did not uncover differences in eye movement behavior that may explain differences in moral judgments. Thus, the clean slate effect is not due to altered information sampling from the environment. Finally, compared to the control group, pupil diameter decreased after hand washing, thus demonstrating a direct physiological effect. The results shed light on the physiological mechanisms behind this type of embodiment phenomenon. PMID:25994083

Deformation-Aware Log-Linear Models

NASA Astrophysics Data System (ADS)

Gass, Tobias; Deselaers, Thomas; Ney, Hermann

In this paper, we present a novel deformation-aware discriminative model for handwritten digit recognition. Unlike previous approaches our model directly considers image deformations and allows discriminative training of all parameters, including those accounting for non-linear transformations of the image. This is achieved by extending a log-linear framework to incorporate a latent deformation variable. The resulting model has an order of magnitude less parameters than competing approaches to handling image deformations. We tune and evaluate our approach on the USPS task and show its generalization capabilities by applying the tuned model to the MNIST task. We gain interesting insights and achieve highly competitive results on both tasks.

Quantification of functional hand grip using electromyography and inertial sensor-derived accelerations: clinical implications.

PubMed

Martin-Martin, Jaime; Cuesta-Vargas, Antonio I

2014-12-11

Assessing hand injury is of great interest given the level of involvement of the hand with the environment. Knowing different assessment systems and their limitations generates new perspectives. The integration of digital systems (accelerometry and electromyography) as a tool to supplement functional assessment allows the clinician to know more about the motor component and its relation to movement. Therefore, the purpose of this study was the kinematic and electromyography analysis during functional hand movements. Ten subjects carried out six functional movements (terminal pinch, termino-lateral pinch, tripod pinch, power grip, extension grip and ball grip). Muscle activity (hand and forearm) was measured in real time using electromyograms, acquired with the Mega ME 6000, whilst acceleration was measured using the AcceleGlove. Electrical activity and acceleration variables were recorded simultaneously during the carrying out of the functional movements. The acceleration outcome variables were the modular vectors of each finger of the hand and the palm. In the electromyography, the main variables were normalized by the mean and by the maximum muscle activity of the thenar region, hypothenar, first interosseous dorsal, wrist flexors, carpal flexors and wrist extensors. Knowing muscle behavior allows the clinician to take a more direct approach in the treatment. Based on the results, the tripod grip shows greater kinetic activity and the middle finger is the most relevant in this regard. Ball grip involves most muscle activity, with the thenar region playing a fundamental role in hand activity. Relating muscle activation, movements, individual load and displacement offers the possibility to proceed with rehabilitation by individual component.

Neural representation of hand kinematics during prehension in posterior parietal cortex of the macaque monkey.

PubMed

Chen, Jessie; Reitzen, Shari D; Kohlenstein, Jane B; Gardner, Esther P

2009-12-01

Studies of hand manipulation neurons in posterior parietal cortex of monkeys suggest that their spike trains represent objects by the hand postures needed for grasping or by the underlying patterns of muscle activation. To analyze the role of hand kinematics and object properties in a trained prehension task, we correlated the firing rates of neurons in anterior area 5 with hand behaviors as monkeys grasped and lifted knobs of different shapes and locations in the workspace. Trials were divided into four classes depending on the approach trajectory: forward, lateral, and local approaches, and regrasps. The task factors controlled by the animal-how and when he used the hand-appeared to play the principal roles in modulating firing rates of area 5 neurons. In all, 77% of neurons studied (58/75) showed significant effects of approach style on firing rates; 80% of the population responded at higher rates and for longer durations on forward or lateral approaches that included reaching, wrist rotation, and hand preshaping prior to contact, but only 13% distinguished the direction of reach. The higher firing rates in reach trials reflected not only the arm movements needed to direct the hand to the target before contact, but persisted through the contact, grasp, and lift stages. Moreover, the approach style exerted a stronger effect on firing rates than object features, such as shape and location, which were distinguished by half of the population. Forty-three percent of the neurons signaled both the object properties and the hand actions used to acquire them. However, the spread in firing rates evoked by each knob on reach and no-reach trials was greater than distinctions between different objects grasped with the same approach style. Our data provide clear evidence for synergies between reaching and grasping that may facilitate smooth, coordinated actions of the arm and hand.

Acquired perforating dermatosis in a patient with Poland syndrome.

PubMed

Fistarol, Susanna K; Itin, Peter H

2003-01-01

Acquired perforating dermatosis (APD) is characterized by umbilicated 1- to 10-mm-measuring papulonodules with a central adherent oystershell-like keratotic plug, typically on the dorsa of the hands, forearms and over the knees. APD is associated with systemic diseases, especially diabetes mellitus and/or renal failure. Histologically the lesions show transepidermal elimination of altered dermal components into a cup-shaped epidermal depression. We present a 69-year-old man with coexisting APD and Poland syndrome (PS), an association not yet described. PS (OMIM 173800) is a rare congenital anomaly consisting of unilateral partial or total absence of the greater pectoralis muscle and ipsilateral symbrachydactyly. Most cases of PS are sporadic as it was in our case. Our patient had, in addition, an untreated diabetic condition, hyperuricaemia, dilated cardiomyopathy and a very recent pulmonary embolism. He responded to therapy with allopurinol. Copyright 2003 S. Karger AG, Basel

Non-affine deformations in polymer hydrogels

PubMed Central

Wen, Qi; Basu, Anindita; Janmey, Paul A.; Yodh, A. G.

2012-01-01

Most theories of soft matter elasticity assume that the local strain in a sample after deformation is identical everywhere and equal to the macroscopic strain, or equivalently that the deformation is affine. We discuss the elasticity of hydrogels of crosslinked polymers with special attention to affine and non-affine theories of elasticity. Experimental procedures to measure non-affine deformations are also described. Entropic theories, which account for gel elasticity based on stretching out individual polymer chains, predict affine deformations. In contrast, simulations of network deformation that result in bending of the stiff constituent filaments generally predict non-affine behavior. Results from experiments show significant non-affine deformation in hydrogels even when they are formed by flexible polymers for which bending would appear to be negligible compared to stretching. However, this finding is not necessarily an experimental proof of the non-affine model for elasticity. We emphasize the insights gained from experiments using confocal rheoscope and show that, in addition to filament bending, sample micro-inhomogeneity can be a significant alternative source of non-affine deformation. PMID:23002395

Hand Therapy

MedlinePlus

... a scar Find a hand surgeon near you. Videos Figures Figure 1: Examples of hand splints PDF ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

Characteristics of hand involvement in a comparative study of two early RA cohorts from the UK and China.

PubMed

Su, Bowen; Ma, Qing; Edwards, Christopher J; Williams, Mark; Adams, Jo

2017-10-01

To compare the characteristics of early hand involvement in rheumatoid arthritis (RA) using two matched populations, from the UK and China. A cohort comparison study was conducted. Sixty Chinese patients recruited from Shanghai, China were matched on gender and age with 60 patients from a prospective early RA cohort from the UK (SARAH trial). The procedures of data collection in China followed the standard operating procedures employed in the SARAH trial. Outcome measures including Michigan Hand Outcomes Questionnaire (MHQ), medication history and physical assessments were used to assess functional ability and hand impairment. UK patients reported significantly more hand pain (P = 0.015), less satisfaction with dominant hand performance (P  = 0.040), more swollen and tender joints (P = 0.016 and P = 0.001) and greater dexterity of both dominant and non-dominant hands (P < 0.001 and P < 0.001), while Chinese patients had higher disease activity indicated by erythrocyte sedimentation rate and C-reactive protein, more rheumatoid factor, less satisfaction in both dominant and non-dominant hand appearances (P < 0.001 and P < 0.001, respectively) and greater dominant hand deformity (P  = 0.003). No statistically significant differences were seen in range of movement and overall hand function as reported by the MHQ. The severity of RA is not milder in China than in the UK and the characteristics of hand involvement tend to be different. Clinicians should consider country-specific differences in managing pain and delivering treatment. It would be helpful for a future study to investigate the RA impact characteristics on a wider range of patients both from within China and from other populations. © 2015 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

7 CFR 926.10 - Acquire.

Code of Federal Regulations, 2011 CFR

2011-01-01

... REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER § 926.10 Acquire. Acquire means to obtain cranberries by any means whatsoever for the purpose of handling cranberries. Effective...

7 CFR 926.10 - Acquire.

Code of Federal Regulations, 2014 CFR

2014-01-01

... REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER § 926.10 Acquire. Acquire means to obtain cranberries by any means whatsoever for the purpose of handling cranberries. Effective...

7 CFR 926.10 - Acquire.

Code of Federal Regulations, 2012 CFR

2012-01-01

... REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER § 926.10 Acquire. Acquire means to obtain cranberries by any means whatsoever for the purpose of handling cranberries. Effective...

7 CFR 926.10 - Acquire.

Code of Federal Regulations, 2013 CFR

2013-01-01

... REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER § 926.10 Acquire. Acquire means to obtain cranberries by any means whatsoever for the purpose of handling cranberries. Effective...

On the absence of InSAR-detected volcano deformation spanning the 1995-1996 and 1999 eruptions of Shishaldin Volcano, Alaska

USGS Publications Warehouse

Moran, S.C.; Kwoun, O.; Masterlark, Timothy; Lu, Z.

2006-01-01

Shishaldin Volcano, a large, frequently active basaltic-andesite volcano located on Unimak Island in the Aleutian Arc of Alaska, had a minor eruption in 1995–1996 and a VEI 3 sub-Plinian basaltic eruption in 1999. We used 21 synthetic aperture radar images acquired by ERS-1, ERS-2, JERS-1, and RADARSAT-1 satellites to construct 12 coherent interferograms that span most of the 1993–2003 time interval. All interferograms lack coherence within ∼5 km of the summit, primarily due to persistent snow and ice cover on the edifice. Remarkably, in the 5–15 km distance range where interferograms are coherent, the InSAR images show no intrusion- or withdrawal-related deformation at Shishaldin during this entire time period. However, several InSAR images do show deformation associated with a shallow ML 5.2 earthquake located ∼14 km west of Shishaldin that occurred 6 weeks before the 1999 eruption. We use a theoretical model to predict deformation magnitudes due to a volumetric expansion source having a volume equivalent to the 1999 erupted volume, and find that deformation magnitudes for sources shallower than 10 km are within the expected detection capabilities for interferograms generated from C-band ERS 1/2 and RADARSAT-1 synthetic aperture radar images. We also find that InSAR images cannot resolve relatively shallow deformation sources (1–2 km below sea level) due to spatial gaps in the InSAR images caused by lost coherence. The lack of any deformation, particularly for the 1999 eruption, leads us to speculate that magma feeding eruptions at the summit moves rapidly (at least 80m/day) from > 10 km depth, and that the intrusion–eruption cycle at Shishaldin does not produce significant permanent deformation at the surface.

Quantifying the Erlenmeyer flask deformity

PubMed Central

Carter, A; Rajan, P S; Deegan, P; Cox, T M; Bearcroft, P

2012-01-01

Objective Erlenmeyer flask deformity is a common radiological finding in patients with Gaucher′s disease; however, no definition of this deformity exists and the reported prevalence of the deformity varies widely. To devise an easily applied definition of this deformity, we investigated a cohort of knee radiographs in which there was consensus between three experienced radiologists as to the presence or absence of Erlenmeyer flask morphology. Methods Using the presence or absence of Erlenmeyer flask morphology as a benchmark, we measured the diameter of the femur at the level of the physeal scar and serially at defined intervals along the metadiaphysis. Results A measured ratio in excess of 0.57 between the diameter of the femoral shaft 4 cm from the physis to the diameter of the physeal baseline itself on a frontal radiograph of the knee predicted the Erlenmeyer flask deformity with 95.6% sensitivity and 100% specificity in our series of 43 independently diagnosed adults with Gaucher′s disease. Application of this method to the distal femur detected the Erlenmeyer flask deformity reproducibly and was simple to carry out. Conclusion Unlike diagnostic assignments based on subjective review, our simple procedure for identifying the modelling deformity is based on robust quantitative measurement: it should facilitate comparative studies between different groups of patients, and may allow more rigorous exploration of the pathogenesis of the complex osseous manifestations of Gaucher′s disease to be undertaken. PMID:22010032

Brain lateralisation and motor learning: selective effects of dominant and non-dominant hand practice on the early acquisition of throwing skills.

PubMed

Stöckel, Tino; Weigelt, Matthias

2012-01-01

Findings from neurosciences indicate that the two brain hemispheres are specialised for the processing of distinct movement features. How this knowledge can be useful in motor learning remains unclear. Two experiments were conducted to investigate the influence of initial practice with the dominant vs non-dominant hand on the acquisition of novel throwing skills. Within a transfer design two groups practised a novel motor task with the same amount of practice on each hand, but in opposite hand-order. In Experiment 1, participants acquired the position throw in basketball, which places high demands on throwing accuracy. Participants practising this task with their non-dominant hand first, before changing to the dominant hand, showed better skill acquisition than participants practising in opposite order. In Experiment 2 participants learned the overarm throw in team handball, which requires great throwing strength. Participants initially practising with their dominant hand benefited more from practice than participants beginning with their non-dominant hand. These results indicate that spatial accuracy tasks are learned better after initial practice with the non-dominant hand, whereas initial practice with the dominant hand is more efficient for maximum force production tasks. The effects are discussed in terms of brain lateralisation and bilateral practice schedules.

Quantitative stress measurement of elastic deformation using mechanoluminescent sensor: An intensity ratio model

NASA Astrophysics Data System (ADS)

Cai, Tao; Guo, Songtao; Li, Yongzeng; Peng, Di; Zhao, Xiaofeng; Liu, Yingzheng

2018-04-01

The mechanoluminescent (ML) sensor is a newly developed non-invasive technique for stress/strain measurement. However, its application has been mostly restricted to qualitative measurement due to the lack of a well-defined relationship between ML intensity and stress. To achieve accurate stress measurement, an intensity ratio model was proposed in this study to establish a quantitative relationship between the stress condition and its ML intensity in elastic deformation. To verify the proposed model, experiments were carried out on a ML measurement system using resin samples mixed with the sensor material SrAl2O4:Eu2+, Dy3+. The ML intensity ratio was found to be dependent on the applied stress and strain rate, and the relationship acquired from the experimental results agreed well with the proposed model. The current study provided a physical explanation for the relationship between ML intensity and its stress condition. The proposed model was applicable in various SrAl2O4:Eu2+, Dy3+-based ML measurement in elastic deformation, and could provide a useful reference for quantitative stress measurement using the ML sensor in general.

Representation and Management of the Knowledge of Brittle Deformation in Shear Zones Using Microstructural Data From the SAFOD Core Samples

NASA Astrophysics Data System (ADS)

Babaie, H. A.; Broda, C. M.; Kumar, A.; Hadizadeh, J.

2010-12-01

Web access to data that represent knowledge acquired by investigators studying the microstructures in the core samples of the SAFOD (San Andreas Observatory at Depth) project can help scientists efficiently integrate and share knowledge, query the data, and update the knowledge base on the Web. To achieve this, we have used OWL (Web Ontology Language) to build the brittle deformation ontology for the microstructures observed in the SAFOD core samples, by explicitly formalizing the knowledge about deformational processes, geological objects undergoing deformation, and the underlying mechanical and environmental conditions in brittle shear zones. The developed Web-based ‘SAFOD Brittle Microstructure and Mechanics Knowledge base’ (SAFOD BM2KB), which instantiates this ontology and is available at http://codd.cs.gsu.edu:9999/safod/index.jsp, will host and serve data that pertains to spatial objects, such as microstructure, gouge, fault, and SEM image, acquired by the SAFOD investigators through the studies of the SAFOD core samples. Deformation in shear zones involves complex brittle and ductile processes that alter, create, and/or destroy a wide variety of one- to three-dimensional, multi-scale spatial entities such as rocks and their constituent minerals and structure. These processes occur through a series of sub-processes that happen in different time intervals, and affect the spatial objects at granular to regional scales within shear zones. The processes bring about qualitative change to the spatial entities over time intervals that start and end with events. Processes, such as mylonitization and cataclastic flow, change the spatial location, distribution, dimension, size, shape, and orientation of some objects through translation, rotation and strain. These processes may also result in newly formed entities, such as a new mineral, gouge, vein, or fault, during one or more phases of deformation. Deformation processes may also destroy entities, such as a

Slow deformation of intervertebral discs.

PubMed

Broberg, K B

1993-01-01

Intervertebral discs exhibit pronounced time-dependent deformations when subjected to load variations. These deformations are caused by fluid flow to and from the disc and by viscoelastic deformation of annulus fibres. The fluid flow is caused by differences between mechanical and osmotic pressure. A mechanical model of lumbar disc functions allows one to calculate both the extent of fluid flow and its implications for disc height as well as the role played by viscoelastic deformation of annulus fibres. From such calculations changes in body height are estimated. Experimental results already documented in the literature offer bases for the determination of the parameters involved. Body height variations are studied, both those related to normal diurnal rhythmicity and those related to somewhat exceptional circumstances. The normal diurnal fluid flow is found to be about +/- 40% of the disc fluid content late in the evening. Viscoelastic deformation of annulus fibres contributes approximately one quarter of the height change obtained after several hours normal activity, but dominates during the first hour.

Patterns of Alloy Deformation by Pulsed Pressure

NASA Astrophysics Data System (ADS)

Chebotnyagin, L. M.; Potapov, V. V.; Lopatin, V. V.

2015-06-01

Patterns of alloy deformation for optimization of a welding regime are studied by the method of modeling and deformation profiles providing high deformation quality are determined. A model of stepwise kinetics of the alloy deformation by pulsed pressure from the expanding plasma channel inside of a deformable cylinder is suggested. The model is based on the analogy between the acoustic and electromagnetic wave processes in long lines. The shock wave pattern of alloy deformation in the presence of multiple reflections of pulsed pressure waves in the gap plasma channel - cylinder wall and the influence of unloading waves from free surfaces are confirmed.

The evolution of functional hand replacement: From iron prostheses to hand transplantation

PubMed Central

Zuo, Kevin J; Olson, Jaret L

2014-01-01

The hand is an integral component of the human body, with an incredible spectrum of functionality. In addition to possessing gross and fine motor capabilities essential for physical survival, the hand is fundamental to social conventions, enabling greeting, grooming, artistic expression and syntactical communication. The loss of one or both hands is, thus, a devastating experience, requiring significant psychological support and physical rehabilitation. The majority of hand amputations occur in working-age males, most commonly as a result of work-related trauma or as casualties sustained during combat. For millennia, humans have used state-of-the-art technology to design clever devices to facilitate the reintegration of hand amputees into society. The present article provides a historical overview of the progress in replacing a missing hand, from early iron hands intended primarily for use in battle, to today’s standard body-powered and myoelectric prostheses, to revolutionary advancements in the restoration of sensorimotor control with targeted reinnervation and hand transplantation. PMID:25152647

Deformation of a crystalline olivine aggregate containing two immiscible liquids: Implications for early core-mantle differentiation

NASA Astrophysics Data System (ADS)

Cerantola, V.; Walte, N. P.; Rubie, D. C.

2015-05-01

Deformation-assisted segregation of metallic and sulphidic liquid from a solid peridotitic matrix is a process that may contribute to the early differentiation of small planetesimals into a metallic core and a silicate mantle. Here we present results of an experimental study using a simplified system consisting of a polycrystalline Fo90-olivine matrix containing a small percentage of iron sulphide and a synthetic primitive MORB melt, in order to investigate whether the silicate melt enhances the interconnection and segregation of FeS liquid under deformation conditions at varying strain rates. The experiments have been performed at 2 GPa, 1450 °C and strain rates between 1 ×10-3s-1 to 1 ×10-5s-1. Our results show that the presence of silicate melt actually hinders the migration and segregation of sulphide liquid by reducing its interconnectivity. At low to moderate strain rates the sulphide liquid pockets preserved a roundish shape, showing the liquid behavior is governed mainly by surface tension rather than by differential stress. Even at the highest strain rates, insignificant FeS segregation and interconnection were observed. On the other hand the basaltic melt was very mobile during deformation, accommodating part of the strain, which led to its segregation from the matrix at high bulk strains leaving the sulphide liquid stranded in the olivine matrix. Hence, we conclude that deformation-induced percolation of sulphide liquid does not contribute to the formation of planetary cores after the silicate solidus is overstepped. A possible early deformation enhanced core-mantle differentiation after overstepping the Fe-S solidus is not possible between the initial formation of silicate melt and the formation of a widespread magma ocean.

Using patient-specific phantoms to evaluate deformable image registration algorithms for adaptive radiation therapy

PubMed Central

Stanley, Nick; Glide-Hurst, Carri; Kim, Jinkoo; Adams, Jeffrey; Li, Shunshan; Wen, Ning; Chetty, Indrin J.; Zhong, Hualiang

2014-01-01

The quality of adaptive treatment planning depends on the accuracy of its underlying deformable image registration (DIR). The purpose of this study is to evaluate the performance of two DIR algorithms, B-spline–based deformable multipass (DMP) and deformable demons (Demons), implemented in a commercial software package. Evaluations were conducted using both computational and physical deformable phantoms. Based on a finite element method (FEM), a total of 11 computational models were developed from a set of CT images acquired from four lung and one prostate cancer patients. FEM generated displacement vector fields (DVF) were used to construct the lung and prostate image phantoms. Based on a fast-Fourier transform technique, image noise power spectrum was incorporated into the prostate image phantoms to create simulated CBCT images. The FEM-DVF served as a gold standard for verification of the two registration algorithms performed on these phantoms. The registration algorithms were also evaluated at the homologous points quantified in the CT images of a physical lung phantom. The results indicated that the mean errors of the DMP algorithm were in the range of 1.0 ~ 3.1 mm for the computational phantoms and 1.9 mm for the physical lung phantom. For the computational prostate phantoms, the corresponding mean error was 1.0–1.9 mm in the prostate, 1.9–2.4 mm in the rectum, and 1.8–2.1 mm over the entire patient body. Sinusoidal errors induced by B-spline interpolations were observed in all the displacement profiles of the DMP registrations. Regions of large displacements were observed to have more registration errors. Patient-specific FEM models have been developed to evaluate the DIR algorithms implemented in the commercial software package. It has been found that the accuracy of these algorithms is patient-dependent and related to various factors including tissue deformation magnitudes and image intensity gradients across the regions of interest. This may

Developing a Virtual Rock Deformation Laboratory

NASA Astrophysics Data System (ADS)

Zhu, W.; Ougier-simonin, A.; Lisabeth, H. P.; Banker, J. S.

2012-12-01

Experimental rock physics plays an important role in advancing earthquake research. Despite its importance in geophysics, reservoir engineering, waste deposits and energy resources, most geology departments in U.S. universities don't have rock deformation facilities. A virtual deformation laboratory can serve as an efficient tool to help geology students naturally and internationally learn about rock deformation. Working with computer science engineers, we built a virtual deformation laboratory that aims at fostering user interaction to facilitate classroom and outreach teaching and learning. The virtual lab is built to center around a triaxial deformation apparatus in which laboratory measurements of mechanical and transport properties such as stress, axial and radial strains, acoustic emission activities, wave velocities, and permeability are demonstrated. A student user can create her avatar to enter the virtual lab. In the virtual lab, the avatar can browse and choose among various rock samples, determine the testing conditions (pressure, temperature, strain rate, loading paths), then operate the virtual deformation machine to observe how deformation changes physical properties of rocks. Actual experimental results on the mechanical, frictional, sonic, acoustic and transport properties of different rocks at different conditions are compiled. The data acquisition system in the virtual lab is linked to the complied experimental data. Structural and microstructural images of deformed rocks are up-loaded and linked to different deformation tests. The integration of the microstructural image and the deformation data allows the student to visualize how forces reshape the structure of the rock and change the physical properties. The virtual lab is built using the Game Engine. The geological background, outstanding questions related to the geological environment, and physical and mechanical concepts associated with the problem will be illustrated on the web portal. In

Mapping three-dimensional surface deformation by combining multiple-aperture interferometry and conventional interferometry: Application to the June 2007 eruption of Kilauea Volcano, Hawaii

USGS Publications Warehouse

Jung, H.-S.; Lu, Z.; Won, J.-S.; Poland, Michael P.; Miklius, Asta

2011-01-01

Surface deformation caused by an intrusion and small eruption during June 17-19, 2007, along the East Rift Zone of Kilauea Volcano, Hawaii, was three-dimensionally reconstructed from radar interferograms acquired by the Advanced Land Observing Satellite (ALOS) phased-array type L-band synthetic aperture radar (SAR) (PALSAR) instrument. To retrieve the 3-D surface deformation, a method that combines multiple-aperture interferometry (MAI) and conventional interferometric SAR (InSAR) techniques was applied to one ascending and one descending ALOS PALSAR interferometric pair. The maximum displacements as a result of the intrusion and eruption are about 0.8, 2, and 0.7 m in the east, north, and up components, respectively. The radar-measured 3-D surface deformation agrees with GPS data from 24 sites on the volcano, and the root-mean-square errors in the east, north, and up components of the displacement are 1.6, 3.6, and 2.1 cm, respectively. Since a horizontal deformation of more than 1 m was dominantly in the north-northwest-south-southeast direction, a significant improvement of the north-south component measurement was achieved by the inclusion of MAI measurements that can reach a standard deviation of 3.6 cm. A 3-D deformation reconstruction through the combination of conventional InSAR and MAI will allow for better modeling, and hence, a more comprehensive understanding, of the source geometry associated with volcanic, seismic, and other processes that are manifested by surface deformation.